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Monday, September 23
 

7:30am HST

TOUR 1 - Window on the Tropical Specialty Crop Industry in Hawaii
Monday September 23, 2024 7:30am - 4:30pm HST
TBA
This tour will showcase large scale commercial and small farm family production, packing or value-added processing of tropical specialty crops including vanilla, coffee, pineapple, cacao, papaya, banana, and passionfruit and Acai in and around the North Shore of Oahu.

This tour is sold out.
Details:
Depart Hilton Hawaiian 7:30 am
Stop #1: Laie Vanilla Company
Stop #2: Kahuku Farms

Lunch at Kahuku Farms

Stop #3 Dole (Cacao Farm)

Stop#4 Dole (Pineapple Packing Plant and Tour Store)

ASHS Professional Interest Group/Committee Sponsor*
Tropical Horticulture
Monday September 23, 2024 7:30am - 4:30pm HST
TBA

8:00am HST

ASHS Leadership Class 3 Meeting
Monday September 23, 2024 8:00am - 12:00pm HST
Monday September 23, 2024 8:00am - 12:00pm HST
Kahili 1

9:00am HST

TOUR 2 - Undergraduate and Graduate Lyons Arboretum Tour/Hike
Monday September 23, 2024 9:00am - 1:00pm HST
TBA
This tour is sold out.

Monday, September 23, 2024: 9:00 AM - 1:00 PM
Welcome to the Lyon Arboretum Student Tour! Immerse yourself in a guided exploration of our cutting-edge facilities, showcasing diverse plant life from Hawaii and beyond. Join us on a captivating hike to a stunning waterfall, where nature and education converge for an unforgettable experience. Gain exclusive insights into the behind-the-scenes world of Lyon Arboretum - a backstage pass to the secrets of our ecological wonders. Discover the beauty and biodiversity of Lyon Arboretum - an adventure awaits!

Details:
Depart Hotel: 8:45 am
Stop #1: Lyon Arboretum
Arrive back at Hotel: 1:00 pm
ASHS Professional Interest Group/Committee Sponsor*
Graduate Student Interest Group

Monday September 23, 2024 9:00am - 1:00pm HST
TBA

9:00am HST

9:00am HST

SCRI DB Project Annual Meeting
Monday September 23, 2024 9:00am - 4:00pm HST
Speakers
avatar for Dorrie Main

Dorrie Main

Professor, Washington State University
I am a member of the Pullman Charter School Initiative team and am particularly interested in how to set up and maintain a thriving Washington State Charter School to serve the needs of Eastern Washington students.
Monday September 23, 2024 9:00am - 4:00pm HST
Nautilus 1

12:00pm HST

ASHS Leadership Joint Class Lunch
Monday September 23, 2024 12:00pm - 1:00pm HST
Monday September 23, 2024 12:00pm - 1:00pm HST
Kahili 2

12:00pm HST

Registration Open - Monday
Monday September 23, 2024 12:00pm - 6:00pm HST
Monday September 23, 2024 12:00pm - 6:00pm HST
Coral Lounge

12:00pm HST

Speaker Ready Room - Monday
Monday September 23, 2024 12:00pm - 6:00pm HST
Monday September 23, 2024 12:00pm - 6:00pm HST
Sea Pearl 1-2

1:00pm HST

ASHS Leadership Class 4 Meeting
Monday September 23, 2024 1:00pm - 5:00pm HST
Monday September 23, 2024 1:00pm - 5:00pm HST
Kahili 1

2:00pm HST

Find Out How to Maximize Your Conference Ride - Student/First Time Attendee Welcome
Monday September 23, 2024 2:00pm - 2:45pm HST
Student/First Time Attendee Welcome: Conference Overview Session
This session will provide the essential information for how to get the most out of your attendance at the ASHS Annual Conference. Specific events, sessions, and competitions will be explained. ASHS staff and volunteers will be on hand to make sure that you are aware of all that ASHS and specifically the ASHS Conference has to offer.
Speakers
Monday September 23, 2024 2:00pm - 2:45pm HST
Coral 2

2:45pm HST

Surfing Your Way to Interview Success: Workshop 1
Monday September 23, 2024 2:45pm - 3:30pm HST
In this segment on interview techniques, we'll equip students and early career professionals with the knowledge and skills to excel in diverse interview formats reflective of the evolving landscape of employment practices. From traditional in-person interviews to virtual and competency-based assessments, we'll explore the nuances of each format and provide strategies for success. As employers adapt their interviewing methods to accommodate remote work and technological advancements, candidates must stay informed and adaptable. We'll delve into the intricacies of virtual interviews, offering guidance on presenting oneself effectively through digital platforms and navigating potential technical challenges. Additionally, we'll address the growing prevalence of competency-based interviews, where candidates are evaluated based on specific skills and experiences. By mastering these various interview formats, students will be well-prepared to showcase their qualifications and secure opportunities in today's dynamic job market.
Moderator
Monday September 23, 2024 2:45pm - 3:30pm HST
Coral 2

3:30pm HST

Riding with the Big Kahunas: A Panel Discussion: Workshop 2
Monday September 23, 2024 3:30pm - 4:00pm HST
In our panel discussion, we're bringing together professionals from diverse sectors—academia, government, and industry—to offer invaluable insights and guidance to students and early career professionals navigating their career paths. With representatives from each sector, attendees will have the opportunity to gain a comprehensive understanding of the different career trajectories available to them and the unique challenges and opportunities associated with each. Our panelists will not only address common questions about job applications, interviews, and career advancement but also offer firsthand perspectives on industry trends, academic research opportunities, and government initiatives. Whether you're considering a career in academia, government, or industry—or exploring the intersections between these sectors—our panelists will provide valuable advice to help you make informed decisions and chart a successful career path. Bring your questions, whether they're about job applications, industry trends, or strategies for career growth, and gain valuable insights from our diverse panel of experts.
Moderator Speakers
FK

Fernanda Krupek

Ohio State University
LT

Lisa Tang

USDA-ARS Appalachian Fruit Research Station

Monday September 23, 2024 3:30pm - 4:00pm HST
Coral 2

4:00pm HST

Surfing the Professional Pipeline at the Career and Graduate School Fair
Monday September 23, 2024 4:00pm - 5:30pm HST
Companies, organizations, universities, and government offices are invited to reserve a free exhibitor table.

Click here to reserve a table.

Students and professional attendees are invited to meet with representatives of hiring companies and organizations, and to learn more about potential jobs and graduate school programs.

Monday September 23, 2024 4:00pm - 5:30pm HST
Coral 1

4:30pm HST

Moderator Training Session (Session will be repeated again on Tuesday morning)
Monday September 23, 2024 4:30pm - 5:00pm HST
Monday September 23, 2024 4:30pm - 5:00pm HST
Coral 2

6:00pm HST

Student and Early Career Attendee Reception
Monday September 23, 2024 6:00pm - 7:00pm HST
All students and early career professionals are invited to a reception/mixer. This is a chance to meet and learn from each other. The GRAD group has organized a fun ice breaker activity, Human Bingo!
Monday September 23, 2024 6:00pm - 7:00pm HST
Nautilus 1
 
Tuesday, September 24
 

7:00am HST

Awardee Breakfast
Tuesday September 24, 2024 7:00am - 7:45am HST
This event is by invitation only for the ASHS award winners.
Tuesday September 24, 2024 7:00am - 7:45am HST
Hibiscus 1

7:00am HST

Moderator Training Session (Repeat of Monday's session)
Tuesday September 24, 2024 7:00am - 8:00am HST
Tuesday September 24, 2024 7:00am - 8:00am HST
Coral 2

7:00am HST

Registration Open - Tuesday
Tuesday September 24, 2024 7:00am - 6:00pm HST
Tuesday September 24, 2024 7:00am - 6:00pm HST
Coral Lounge

7:00am HST

Speaker Ready Room - Tuesday
Tuesday September 24, 2024 7:00am - 6:00pm HST
Tuesday September 24, 2024 7:00am - 6:00pm HST
Sea Pearl 1-2

8:00am HST

Plenary Welcome and ASHS Awards Ceremony
Tuesday September 24, 2024 8:00am - 9:00am HST
Tuesday September 24, 2024 8:00am - 9:00am HST
Coral 3

8:00am HST

AHIS Lightning Competition
Tuesday September 24, 2024 8:00am - 10:00am HST
Moderator
TV

Tripti Vashisth

University of Florida
Tuesday September 24, 2024 8:00am - 10:00am HST
South Pacific 4

9:00am HST

Keynote Speaker: Heidi Leianuenue Bornhorst
Tuesday September 24, 2024 9:00am - 10:00am HST
"Native Hawaiian Plants for Landscaping, Xeriscaping and Conservation"
Presented by Horticulturist and Arborist, Heidi Leianuenue Bornhorst

Heidi Leianuenue Bornhorst is a Horticulturist and Certified Arborist specializing in native Hawaiian plants, Horticulture, Xeriscaping and Restoration of native habitats.
Heidi has an M.S. in Horticulture and a Certificate in Public Administration. She is a speaker and garden writer.
She has worked in Leadership positions in public gardens, including the Hale Koa Hotel, Honolulu Botanical Gardens, (Foster, Wahiawa, Liliuokalani, Koko Crater, and Ho`omaluhia), and as Horticulturist at the Honolulu Zoo. She has also worked at the National Tropical Botanical Garden on Kaua`i, Lyon Arboretum, U.H. Manoa and Kupuna for Hawaiian Studies, DOE.
She is a landscape design and maintenance Consultant, with her company Pruning for Productivity, helping people grow their Dream Gardens (and be practical and scientific too), and as an Arborist, providing right sizing and professional pruning of valuable fruit trees.
She is the O`ahu Coordinator for the Breadfruit Institute helping with `Ulu tree distribution, Horticulture, proper tree trimming, and long-term care and maintenance.
Heidi was a founding partner of the Mangoes at the Moana Hotel annual festival, where she spoke about caring for and proper pruning and planting of mango trees, a judge in the Best Mango tasting contest and Mango recipe contest. Our goal: A Fruit tree in every Hawaii Garden!
She got her start as a Volunteer at Foster Garden, and as an Apprentice Gardener at the National Tropical Botanical Garden. She holds a B.S. and M.S. from U.H. Manoa. She was an apprentice gardener at Longwood Gardens in Pennsylvania, and at the RHS Wisley Botanic Garden in England.
She authored the book:  Growing Native Hawaiian Plants and wrote the Hawai`i Gardens column for the Honolulu Star Advertise for 30 years.
She was the Garden expert on ‘the Morning Garden’ early morning KITV.
She is a noted public speaker, expert tour guide, and Hike leader.

Speakers

Tuesday September 24, 2024 9:00am - 10:00am HST
Coral 3

9:59am HST

Commercial Horticulture 1 (CHEX 1)
Tuesday September 24, 2024 9:59am - 11:30am HST
A comprehensive analysis of Vidalia Onions transplanting and its impacts - Regimar do Santos
Is Winter Squash a Potential Alternative Cucurbit Vegetable Crop to Combat Whitefly and Whitefly-Transmitted Viruses for Fall Production in Southern Georgia? - Nirmala Acharya
Evaluating Onsite Nitrate and Potassium Sensors - Destany Westlake
Filling the Gaps for Informed Adoption of Carolina Strong Back Grafted Nursery: Transplanting Time and Spacing Optimization - Sukhman Kaur
Substrate Hydro-Physical Properties in Soilless Agriculture: Investigating the Role of Container Geometry on Substrate Air and Water Profiles - Brandan Shur
Kenaf (Hibiscus cannabinus) Compost As An Alternative To Peat - Shawn Steed
Moderator
NA

Nirmala Acharya

University of Georgia
Tuesday September 24, 2024 9:59am - 11:30am HST
South Pacific 2

9:59am HST

Nursery Crops 1 (NUR 1)
Tuesday September 24, 2024 9:59am - 11:30am HST
Seventy Years of Evaluations and Selections of Ornamentals by the NDSU Woody Plant Improvement Program. - Todd West
Micropropagation and production of Amur and Norway maple triploids - Ryan Contreras
Tea Plant Propagation for Nursery Production - Carol Miles
Establishment of Fraser Fir Christmas Tree Plantations in Response to Mulch and Root Dips - Bert Cregg
Cultivating Control: Effective Suppression Methods for Jumping Worms in Container Nursery Production - Jenna Simon
Effects of Water Quality and Fertilization Practices on Container Tree Growth in Nurseries - Zachary Davis
Moderator
BC

Bert Cregg

Michigan State University
Dr. Bert Cregg is a professor of Horticulture and Forestry at Michigan State University. He conducts research and extension programming on the physiology and management of trees in landscapes and nursery and Christmas tree production.
Tuesday September 24, 2024 9:59am - 11:30am HST
South Pacific 3

9:59am HST

Plant Nutrient Management 1 (PNM 1)
Tuesday September 24, 2024 9:59am - 11:30am HST
Evaluating Nitrogen Application Rates on Open-field Fresh-market Tomato Production in North Mississippi: Preliminary Results - Ibukun Ayankojo
Effect of Bacterial Biostimulant Applied at Different N Rates in Potatoes - Lakesh Sharma
Evidence of Downregulation in Atmospheric Nitrogen-Fixation Associated with Native Hawaiian Sugarcane - Noa Lincoln
Nitrate Leaching Potential of UAN and Organic Soybean Extract Fertilizers Applied to Lettuce - Dave Goorahoo
Evaluating the N Status of Tomato Supplied with Soluble and Controlled-release Urea Formulations - Laura Jalpa
Understanding Nitrogen Uptake Potential of Two Wetland Plants Under Varied Water Temperatures and Nitrogen Concentrations - Saroj Burlakoti
Understanding the Boron-Yield Relationship in Pistachio Orchards - Mukesh Mehata
Moderator
LJ

Laura Jalpa

University of Florida
Tuesday September 24, 2024 9:59am - 11:30am HST
Kahili

9:59am HST

Growth Chambers and Controlled Environments 1 (CE 1)
Tuesday September 24, 2024 9:59am - 12:00pm HST
Transcriptomic Analysis of Kale (Brassica oleracea) Grown Under Different Light Emitting Diode Wavelengths Revealed Potential Genes Responsible for Phenotypic Changes - Tristan Sanders
Blue Light Mediates Far-Red Light Effects on Increasing Leaf Area and Shoot Mass of Kale and Lettuce - Jiyong Shin
Interactions Between Blue Light and Far-Red Light on Growth of Culinary Herbs - Bridget Knight
Blue and Green Light and Temperature Interactively Regulate Growth, Morphology, Physiology, and Phytochemicals of Lettuce - Sangjun Jeong
Switching From Low to High Blue Light Before Harvest Increases Nutritional Quality While Maintaining High Biomass in Red-leaf Lettuce Under Elevated CO2 - Shem Msabila
Supplemental Blue and UV-B Light Enhances Amino Acid-Derived Flavor Compounds in Greenhouse-Grown Tomatoes - Samikshya Bhattarai
Characterizing the effect of blue light on water relations of unrooted cuttings during indoor acclimation - Ana Sofia Gomez
Shedding Light on Nutrition: The Influence of Supplemental Lighting on Glucosinolate Concentrations in Brassica Plants and Their Potential Anticarcinogenic Effects in Human Diets - Skyler Brazel
Moderator
SB

Skyler Brazel

University of Tennessee - Knoxville
Tuesday September 24, 2024 9:59am - 12:00pm HST
Coral 1

9:59am HST

Marketing and Economics (MKEC)
Tuesday September 24, 2024 9:59am - 12:00pm HST
Consumer Shopping Destination Preferences For Outdoor Garden Plants In The United States - Vivek Bist
Producer Awareness and Treatment of Ambrosia Beetle: Evidence from a Producer Survey - Ben Campbell
Consumer Awareness, Treatment Perception, and Purchasing Response to Flathead Borer - Ben Campbell
Market Research to Reinvigorate the Processed Vegetable Industry using Consumer Sensory Evaluations - Ann Colonna
Perceptions and Climate Change Adaptation Behavior Among New Mexico's Specialty Crops Growers - Sawssan Boufous
Consumer Preferences for Commercially Available Poinsettia Cultivars in South Mississippi - Patricia Knight
Understanding the Characteristics of Ethnic Markets and Help Small Growers to Find Niche - ChyiLyi Liang
Consumers' WTP on Sustainability Turfgrass Attributes with Consideration of Aesthetic Attributes and Water Conservation Policies - Chanjin Chung
Moderator
CC

Chanjin Chung

Oklahoma State University
Tuesday September 24, 2024 9:59am - 12:00pm HST
South Pacific 1

9:59am HST

Pomology 1 (POM 1)
Tuesday September 24, 2024 9:59am - 12:00pm HST
Prohexadione Calcium Does Not Affect Thinning Efficacy of 1-aminocyclopropane-1-carboxylic Acid in ‘Golden Delicious’ - Annie Vogel
Carbohydrate Status of Apple Fruitlets following Chemical Thinner Application Informs Sink Strength and Fruit Set - Laura Hillmann
Performance of a reflectance spectroscopy model to predict apple fruitlet thinning efficacy - James Larson
Overexpression of the Coding Sequence of Ma1 Decreases Fruit Acidity in ‘Royal Gala’ Apple - Lailiang Cheng
Striking the Right Balance: Innovative PGR Strategies for Fruit Drop Mitigation and Color Enhancement in Apples - Sherif Sherif
Rapid Fruit Growth Rates of Honeycrisp Apples Cause Premature Dysfunction of Xylem, Reduced Peel Calcium, and Increased Susceptibility to Bitter Pit - Chayce Griffith
Carbohydrate And Nitrogen Storage Are Inversely Affected By Crop Load For 'Honeycrisp' And 'Gala' Apples - Thiago Campbell
Impacts of Rootstock and Crop Load Adjustment on Fruit Quality and Mineral Nutrients in ‘Honeycrisp’ Apple - Esmaeil Fallahi
Moderator
LC

Lailiang Cheng

Cornell University
Tuesday September 24, 2024 9:59am - 12:00pm HST
Nautilus 1

10:00am HST

CE 1 - Transcriptomic Analysis of Kale (Brassica oleracea) Grown Under Different Light Emitting Diode Wavelengths Revealed Potential Genes Responsible for Phenotypic Changes
Tuesday September 24, 2024 10:00am - 10:15am HST
Light emitting diodes (LEDs) of different wavelengths significantly influenced kale growth, morphology, and nutrient content. The importance of indoor agriculture is being recognized, but few studies have investigated the influence of LEDs, particularly green wavelengths, on crops at the transcriptome level. The objective of this study was to use RNA sequencing technology to elucidate the genetic response of kale to blue (BV), green (G), and red (RF) LEDs compared to the combination of all the LEDs (RFBVG), control. Results revealed total amount of differentially expressed genes (DEGs) was 1373 for kale grown under BV LEDs, 924 under G LED, and 133 under the RF LED treatments. DEGs enriched in kale grown under RF LEDs played roles in regulating hormone metabolic processes and oxidoreductase activity. In the BV treatment, several enzymes in the phenolic biosynthetic pathway were upregulated compared to the control which may explain previous results reporting higher levels of phenolic content in kale grown under BV LEDs. In the G LED treatment, the expression of genes related to photosynthesis, heme binding, and oxidoreductase activity were upregulated compared to those in the control group. These results may support previous findings of higher iron content in kale grown under G LEDs. Further, the G LED treatment upregulated the expression of cytochrome P450 enzymes, which play key roles in plant growth and stress responses. Understanding the molecular mechanisms underlying the effects of different LED wavelengths by RNAseq provides information to improve indoor cultivation practices that optimize crop growth and nutrient value.
Speakers
TS

Tristan Sanders

West Virginia University
NA
Co-authors
JT

Janet Tou

West Virginia University
NA
NW

Nicole Waterland

West Virginia University
NA
YM

Youyoun Moon

West Virginia University
NA
Tuesday September 24, 2024 10:00am - 10:15am HST
Coral 1

10:00am HST

CHEX 1 - A comprehensive analysis of Vidalia Onions transplanting and its impacts
Tuesday September 24, 2024 10:00am - 10:15am HST
Onions are a key crop in the United States. In 2023, 138,000 acres were cultivated in the country with onions. Georgia harvested 11,700 acres in 2023, reaching an average production of 129,000 tons. The onion transplanting process is crucial to the crop cycle and is directly linked to the production potential and quality of the bulbs. Every year, thousands of workers are employed to transplant onion seedlings, which results in a wide variation in operational performance and quality of execution between them. These factors are influenced by the experience and conditions in which the workers operate, which can lead to failures in the process, such as double plants, partially transplanted and plants that have fallen to the ground. Furthermore, manual work is slow and requires many workers, increasing the cost of the operation. Therefore, we aimed with this study to assess the time required to manually transplant onions, the quality of manual transplanting, and the impact of inadequate transplanting on crop development. To assess how much time it takes to transplant an acre of onions, and the quality of transplanting, twenty-five people were observed during their work at a commercial field in Glennville-GA. To assess the impact of poor-quality transplanting, an experiment was carried out in four 10ft replications (10x4ft beds) in Reidsville-GA, simulating four situations observed in the commercial field. Treatments were: T1: 25% of the plants in the plot laying on the ground, T2: 25% partially transplanted, T3: 100% properly transplanted, T4: 25% multiple transplanted, T5: 100% laying on the ground. The difference in operational efficiency between workers exceeded ~20 hours per acre. Results indicated that, in average, one person transplanted 1 acre in approximately 30 hours. The fastest person in the crew transplanted in 22 hours, while the slowest took around 40 hours to transplant 1 acre. Poor-quality transplanting of seedlings exceeded up to 11%. The average number of multiple seedlings was 1%, partially transplanted seedlings was 6%, and laying on the ground was 5.5%. Plant development was assessed based on the number of leaves. Properly transplanted seedlings generated a greater number of leaves compared to the other treatments. Higher leaf number was observed in treatment 3 with an average of 7.33 leaves per plant. All the treatments differed from treatment 5, which had an average of 4.6 leaves per plant. Results indicate that good practices on transplanting can increase onion yield.
Speakers
RD

Regimar dos Santos

University of Georgia
Bachelor's degree in agronomic engineering from the Federal University of Mato Grosso do Sul, Brazil at 2021. Master's degree in plant production with an emphasis on computational intelligence in genetic improvement at 2022, with a doctorate in progress at the state university of... Read More →
Co-authors
LO

Luan OIiveira

University of Georgia
NA
LS

Lucas Sales

University of Georgia
Agronomy Engineer graduated from the Federal University of Paraíba. With experience in the management and cultivation of Ornamental Plants, through a year of experience working in Greenhouses in the state of New Hampshire, USA. Experienced in the management and cultivation of vegetables... Read More →
MB

Marcelo Barbosa

University of Georgia
Tuesday September 24, 2024 10:00am - 10:15am HST
South Pacific 2

10:00am HST

MKEC - Consumer Shopping Destination Preferences For Outdoor Garden Plants In The United States
Tuesday September 24, 2024 10:00am - 10:15am HST
Outdoor garden plants are integral products in the nursery and garden stores industry in the United States. Industry reports indicate that home improvement centers and big-box stores pose a significant threat to small garden centers, nursery stores, and ornamental farmers through price competition while small local ornamental businesses tend to focus on personalized products and services to compete with chain retail stores. Identifying the key characteristics of consumer clusters that influence consumer shopping destination preferences can be useful for industry players to devise efficient marketing plans for their niche markets. This study employs cluster analysis techniques and multinomial logistic regression on the cross-sectional data collected from an online survey of 609 consumers to estimate the influence of consumer economic and socio-demographic characteristics on their shopping destination choices. The results from this study indicate that retail consumers of outdoor garden plants can be categorized broadly into four clusters: home improvement center shoppers (47.4%), big-box center shoppers (13.5%), local garden center shoppers (21.2%), and farmers’ market shoppers (17.9%). This study also finds that age, ethnicity, education, household income, number of children in the household, urbanicity, housing arrangements, and political inclination are useful predictors of shopping destination preferences for outdoor garden plants. This study adds valuable information to the market research literature for the retail ornamental horticulture industry.
Speakers
VB

Vivek Bist

Agricultural & Natural Resources Agent, University of Georgia
Co-authors
BC

Benjamin Campbell

University of Georgia
JM

Jeffrey Mullen

University of Georgia
NA
Tuesday September 24, 2024 10:00am - 10:15am HST
South Pacific 1

10:00am HST

NUR 1 - Seventy Years of Evaluations and Selections of Ornamentals by the NDSU Woody Plant Improvement Program.
Tuesday September 24, 2024 10:00am - 10:15am HST
The North Dakota State University (NDSU) Woody Plant Improvement Program has been servicing the Northern Great Plains for 70 years, beginning germplasm trial evaluations in 1954. NDSU purchased an 80-acre (~32 hectares) farm in the early 1970s to be established as the NDSU Horticulture Research Farm near Absaraka, ND and began trial plantings in fall of 1974. This research farm provides ideal horticultural soil for evaluation and breeding projects for ND. Approximately 45 acres (~18 hectares) of this farm is used for evaluation, selection and breeding of woody ornamental plants including a 35-acre (~14 hectares) research arboretum. This research arboretum is the most extensive collection of woody ornamental plants in North Dakota and in the Northern Great Plains. There have been over 15,000 accessions obtained, evaluated, and developed since planting began in 1974. Accessions have been collected from local, regional, national, and international sources. After 50 years, this program has introduced 62 superior ornamental woody plants for production and sale with 44 active registered trademarks with the U.S. Patent and Trademark Office. NDSU woody plant introductions have a nursery wholesale sale value of over $2.0 million and a $6.0 million value in retail sales for 2022 alone. Introductions are currently being propagated for sale by commercial wholesale firms in four countries: Australia, Canada, England, and the United States (22 states, including 35 nurseries). The primary focus of this program is with increasing the diversity and availability of woody plants with increased disease/insect resistance and winter hardiness for landscapes throughout North Dakota, region, and nation. One issue that this program is addressing is that native woody (trees and shrubs) plant species diversity is extremely low in the central United States, especially in North Dakota. Most of the available trees and shrubs in the specialty crop nursery trade in North Dakota are non-native introductions. Many non-native plants have been shown to be invasive to native environments. Woody plant research has reacted to this issue utilizing sterility breeding. This results in new cultivars that are not considered invasive and are allowed to be utilized by the commercial nursery and landscape industry, even in states where they are banned. Sterility breeding through polyploid induction has become a focus of the NDSU Woody Plant Improvement Program. The research focus of this project is to induce, or develop, polyploids produce sterile cultivars to be used in the nursery and landscape trade.
Speakers
TW

Todd West

North Dakota State University
Dr. Todd P. West is currently a Professor at North Dakota State University and director of the NDSU Woody Plant Improvement Program. He earned his Ph.D. from Southern Illinois University at Carbondale. The NDSU Woody Plant Improvement Program focuses on the development of new woody... Read More →
Tuesday September 24, 2024 10:00am - 10:15am HST
South Pacific 3

10:00am HST

PNM 1 - Evaluating Nitrogen Application Rates on Open-field Fresh-market Tomato Production in North Mississippi: Preliminary Results
Tuesday September 24, 2024 10:00am - 10:15am HST
Nitrogen (N) is an essential crop nutrient and is a major production requirement for vegetable crops, critical for optimum yield and fruit quality. An adequate supply of N improves plant growth and health, reduces plant susceptibility to diseases, and minimizes the risk of groundwater and surface water pollution. There is limited information on the N requirements for commercial vegetable production systems in Mississippi (MS). This project aims to establish the critical N application rate for open-field fresh-market tomato production in northeast Mississippi. The study was conducted at North Mississippi Research and Extension Center, Verona MS. The evaluated treatments (0, 73, 109, 145, 218, and 290 kg/ha-N) were arranged in a randomized complete block design with three replicates per treatment. For each treatment, the total required amount of nitrogen application was applied at a split rate of 50% preplant (ammonium nitrate, 33-0-0 and fertigation (Calcium nitrate, 15.5-0-0). Fertigation was applied weekly starting at 6 weeks after transplanting. Both potassium and phosphorus were the same for all treatments and applied at 100% pre-plant using 0-46-0 and 0-0-60 formulations respectively. Yield data were collected at fruit maturity and analyzed for statistical differences among treatments. Preliminary results suggest significant differences (p < 0.05) among treatments for leaf tissue N concentration. The total marketable yield and extra-large fruit categories were highest (p < 0.05) at 290 kg/ha-N compared to other treatments. The results also clearly demonstrated that the observed yield increase at a higher N rate (290 kg/ha-N) was attributed to increase in total fruit number at maturity and bigger fruit size. The observed yield for the unmarketable fruit category was highest at N application rate of ≤ 73 kg/ha. Based on the preliminary results obtained, the optimum N application rate for open-field fresh-market tomato production in northeast MS could be up to 290 kg/ha. However, more studies are currently being conducted to validate these preliminary results.
Speakers
avatar for Timothy Ayankojo

Timothy Ayankojo

Assistant Professor, Mississippi State University
Co-authors
JW

Jeff Wilson

Mississippi State University Extension
TH

Thomas Horgan

Mississippi State University
NA
Tuesday September 24, 2024 10:00am - 10:15am HST
Kahili

10:00am HST

POM 1 - Prohexadione Calcium Does Not Affect Thinning Efficacy of 1-aminocyclopropane-1-carboxylic Acid in ‘Golden Delicious’
Tuesday September 24, 2024 10:00am - 10:15am HST
Apple’s (Malus × domestica Borkh.) tendency towards biennial bearing necessitates management strategies such as fruit thinning and vigor control. Applications of plant growth regulators to manage crop load and vigor overlap in the spring. A precursor to ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC; Accede®) was recently registered as a chemical fruit thinner in the USA. Prohexadione-calcium (P-Ca) is a gibberellin biosynthesis inhibitor widely used to manage vigor. It is suspected that P-Ca may interfere with ACC precursors, decreasing thinning efficacy of ACC. We evaluated the effects and interactions of ACC and P-Ca on shoot growth, ethylene evolution, leaf area, and yield responses of mature ‘Golden Delicious’. The experiment was conducted in 2023, in Mills River, NC, USA. Treatments included ACC (400 mg∙L-1), P-Ca (250 mg∙L-1), ACC P-Ca, and an untreated control. Application of P-Ca occurred on three dates. ACC was applied when average fruit diameter was ~20 mm. Across all measured responses, there were no interactions between ACC and P-Ca. P-Ca had a negative main effect on shoot growth rate (48.7–75.4% reduction). ACC reduced leaf number of spurs 4 and 9 days after treatment (DAT). Ethylene evolution in fruit and spurs was increased by ACC 1, 4, and 9 DAT (spur: 1.1e4%, 5300%, and 515%, respectively; fruit: 9200%, 725%, and 222%, respectively). ACC had a negative effect on fruit number, yield, and crop density (60.1%, 56.5%, and 60.3% reduction, respectively). These results indicate that ACC and P-Ca can be used simultaneously to manage crop load and vigor, respectively
Speakers
AV

Annie Vogel

North Carolina State University
Co-authors
CC

Christopher Clavet

North Carolina State University
NA
JL

James Larson

Utah State University
TK

Thomas Kon

North Carolina State University
NA
Tuesday September 24, 2024 10:00am - 10:15am HST
Nautilus 1

10:00am HST

Meet the 2024 Award Recipients
Tuesday September 24, 2024 10:00am - 11:00am HST
Tuesday September 24, 2024 10:00am - 11:00am HST
Coral 5

10:00am HST

Workshop: Specialty Crop Community Databases and Breeding Data Management Tools
Tuesday September 24, 2024 10:00am - 12:00pm HST
In this interactive workshop, participants will be provided training on how to use Rosaceae (GDR, www.rosaceae.org), Vaccinium (GDV, www.vaccinoum.org) and Citrus (www.citrusgenomedb.org) specialty crop databases resources, as well as the Breeding Data Management tools, BIMS (www.breedwithbims.org), and the Field Book App for phenotype data collection. Using a case-study approach we will focus on how to use these integrated resources most efficiently for research and crop improvement efforts, how to apply FAIR data principles to sharing and submitting research data to these databases at the time of publication and facilitate a robust dialogue between researcher, breeders and the development team on needed improvements and long-term sustainability options for these resources.

This interactive workshop will bring together researchers and breeders to accelerate research and crop improvement in specialty crops. It will provide training and feedback on how to most effectively use the NIFA SCRI and National Research Support project 10 (NRSP10) funded Rosaceae, Citrus, and Vaccinium specialty crop databases and breeding data management resources (BIMS and Field Book), learn how to follow FAIR data principles, foster better two-way communication for increased feedback from researchers on further development of these resources, and continue to build a robust community around these research and crop improvement tools. The trainers include users and developers of these resources, ranging from early career to well-known and respected research enabling resource generators.

The Genome Database for Rosaceae (GDR), Genome Database for Vaccinium, and Citrus Genome Database (CGD) offer critical resources and tools to enable genomic, genetic, and breeding research for fruit, nut, and ornamental crops of great economic importance to the U.S. In addition, BIMS (BreedwithBIMS.org) and the Field Book APP provide widely used tools for managing plant breeding program data. While these resources are heavily used worldwide, many researchers are unaware of the full potential of using them and how they can contribute their own data for wider recognition and reuse. This interactive workshop aims to bridge this knowledge gap by providing hands-on training for specialty crop researchers on how to best use these resources and contribute their data. The workshop will also solicit ideas from participants on how to improve these databases and discuss the various options to make them sustainable in the long term. The workshop will bolster the utilization of integrated big data, promote future data sharing, and ensure that data is FAIR (Findable, Accessible, Interoperable, and Reusable).

The workshop aims to bring together researchers to accelerate research by more effective use of specialty crop databases and breeding data management resources, encouraging data submission at the time of publication, and gaining feedback from researchers. Through hands-on training, participants will become more familiar with the database resources and breeding data management tools, learn how to submit their data, and provide essential input for improving these databases and their long-term sustainability.

Coordinator(s)
  • Dorrie Main, Washington State University, Pullman, WA, United States
Moderator(s)
  • Cameron Peace, Washington State University, Horticulture, Pullman, WA, United States

Speaker/Participant(s)
  • Dorrie Main, Washington State University, Pullman, WA, United States
Introduction to the Workshop and Specialty Crop Research Databases (15 mins)

  • Jodi Humann, Washington State University, Horticulture, Pullman, WA, United States
How to efficiently use integrated genomics data and tools for research (20 mins)

  • Sook Jung, Washington State University, Horticulture, Pullman, WA, United States
    How to efficiently use integrated genetics data and tools for research (20 mins)

  • Nahla Bassil, USDA ARS, National Clonal Germplasm Repository, Corvallis, OR, United States
    How to efficiently use integrated germplasm and genotype data for research (15 mins)
    Summary:

  • Trevor Rife, Clemson University, Plant and Environmental Sciences Department, Florence, SC, United States
    How to use the Field Book App for phenotypic data collection (15 mins)
  • Sushan Ru, Auburn University, Auburn, United States
    How to use the Breeding Information Management System, BIMS, for Crop Improvement (20 mins)
  • Cameron Peace, Washington State University, Horticulture, Pullman, WA, United States


Moderator
CP

Cameron Peace

Washington State University
Speakers
avatar for Dorrie Main

Dorrie Main

Professor, Washington State University
I am a member of the Pullman Charter School Initiative team and am particularly interested in how to set up and maintain a thriving Washington State Charter School to serve the needs of Eastern Washington students.
SR

Sushan Ru

Auburn University
JH

Jodi Humann

Washington State University
Tuesday September 24, 2024 10:00am - 12:00pm HST
Coral 2

10:00am HST

National Issues Committee
Tuesday September 24, 2024 10:00am - 12:00pm HST
Tuesday September 24, 2024 10:00am - 12:00pm HST
Sea Pearl 3

10:00am HST

ASHS Conference Central - Tuesday Hours
Tuesday September 24, 2024 10:00am - 5:00pm HST
Tuesday September 24, 2024 10:00am - 5:00pm HST
Coral 4/5

10:00am HST

Exhibit Hall Hours - Tuesday
Tuesday September 24, 2024 10:00am - 5:00pm HST
Tuesday September 24, 2024 10:00am - 5:00pm HST
Coral 4/5

10:14am HST

Weed Control and Pest Management 1 (WCPM 1)
Tuesday September 24, 2024 10:14am - 11:45am HST
Optimizing Tomato Tolerance to Herbicides: Harnessing Biochar Herbicide Protection Pods for Enhanced Weed Control - Te Ming Tseng
Evaluation of Plant Hormones and Other Seed Treatments to Reduce Injury Caused by Preemergent Herbicides on Direct-seeded Turnips and Collard Greens - Matthew Cutulle
Flaming, Cultivation, and Handweeding Weed Control in Organic Carrot Production Systems with Different Fertilizer Types - Peter Dittmar
Tolerance of Peppermint to Herbicides Applied Post-Harvest - Stephen Meyers
Developing a Biobased, Compostable Mulch that Crops Grow Through - Samuel Wortman
Evaluating Application Approaches for Enhancing the Weed Suppression Effectiveness and Crop-Safety of Preemergence Herbicides in Vegetable Plasticulture Production - Ramdas Kanissery
Moderator
SM

Stephen Meyers

Purdue University
Tuesday September 24, 2024 10:14am - 11:45am HST
Lehua Suite

10:14am HST

Teaching Methods 1/ Administrators (TCHG 1/ADMIN)
Tuesday September 24, 2024 10:14am - 12:15pm HST
FFAR Fellows:  Opportunities for Horticulture PhD Students - John Dole
Nurturing Knowledge: The Impact of Assuming Professional Role in Achieving Learning Objectives in Upper-Level Horticulture Courses - Shivani Kathi
Mid-semester Teaching Evaluations to Enhance Course Communication - Rebekah Maynard
Evaluation of Packback - an AI-Assisted Writing Program for Student Assignments in Horticulture Courses - Navreet K Mahal
Evolution Of An Undergraduate Tropical Crop Production Systems Course - Kent Kobayashi
Service-learning Horticulture Students Growing Food for Themselves and Others - Carl Motsenbocker
Hands-on Horticulture Activities for Undergraduate Introduction to Horticulture Courses - Claire Luby

Moderator
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
Tuesday September 24, 2024 10:14am - 12:15pm HST
South Pacific 4

10:15am HST

CE 1 - Blue Light Mediates Far-Red Light Effects on Increasing Leaf Area and Shoot Mass of Kale and Lettuce
Tuesday September 24, 2024 10:15am - 10:30am HST
There are contrasting effects of far-red (FR; 700–750 nm) light on leaf area and biomass in plants. These differences have been attributed to photon flux density (PFD) and species/cultivar differences. In a previous experiment, total PFD (TPFD) did not mediate the influence of FR light on leaf area and shoot mass when the TPFD alterations were only of red (R; 600–699 nm) and FR light. Therefore, we hypothesized that blue (B; 400–499 nm) light controls the influence of TPFD in regulating the effects of FR light on leaf area and shoot mass. We cultivated kale (Brassica oleracea var. sabellica) ‘White Russian’ and lettuce (Lactuca sativa) ‘Rex’ and ‘Rouxai’ under 12 lighting treatments with a 24 h∙d−1 photoperiod and TPFDs of 85, 170, 255, or 340 µmol∙m−2∙s−1 and FR fractions [FR-PFD divided by the sum of R and FR PFD] of 0.00, 0.17, or 0.33. The alterations in the TPFDs were solely due to B-PFD; the sum of R and FR PFD was constant in all treatments. Preliminary results indicate that elevated FR fraction did not increase leaf area and shoot mass of all three crops in the absence of B light, when the TPFD was 85 µmol∙m−2∙s−1. However, a high B-PFD and thus TPFD amplified the effects of a high FR fraction at increasing leaf area and shoot mass of all three cultivars. These high FR-fraction effects were correlated with increased biomass partitioning to leaves at a high B-PFD and thus TPFD. These results imply that the contrasting effects of FR light on leaf area and biomass in previous studies could be attributed to the B-PFD. In addition, the influence of TPFD on FR-fraction effects is primarily influenced by the B-PFD.
Speakers
JS

Jiyong Shin

Michigan State University
Co-authors
ER

Erik Runkle

Michigan State University
NA
Tuesday September 24, 2024 10:15am - 10:30am HST
Coral 1

10:15am HST

CHEX 1 - Is Winter Squash a Potential Alternative Cucurbit Vegetable Crop to Combat Whitefly and Whitefly-Transmitted Viruses for Fall Production in Southern Georgia?
Tuesday September 24, 2024 10:15am - 10:30am HST
The predominant cucurbit vegetable crop during fall in Georgia is summer squash with production value of around $94.08 million on 7,757 acres in 2022 while winter squash acreage was insignificant. Whitefly and whitefly-transmitted viruses (WTV) account for 30-50% summer squash yield losses on average and threaten squash production during fall in the region. Cucurbit leaf crumple virus (CuLCrV), Cucurbit yellow stunting disorder virus (CYSDV) and Cucurbit chlorotic yellows virus (CCYV) are the prominent WTV in southern Georgia. We carried out an experiment during fall 2023 in Tifton, Georgia to evaluate tolerance of winter squash varieties for whitefly and WTV and to study their potentiality for fall production in the region. We compared ten commercial hybrid varieties of which two were acorn types (‘Tay Belle’ and ‘Table Ace’), five were butternut types (‘Waltham’, ‘Ceres’, ‘Atlas’, ‘Ultra HP’ and ‘Genesis’), and one each of a hubbard type (‘Golden Hubbard’), a kabocha type (‘Sweet Mama’) and a calabaza type (‘La Estrella’). We collected data on whitefly number, silver leaf disorder, virus incidence and severity, and fruit yield. In addition, we ran quantitative polymerase chain reaction (qPCR) and quantitative reverse transcription polymerase chain reaction (RT-qPCR) on leaf samples to detect and quantify viruses. There were significant differences between winter squash varieties for whitefly feeding preference, silver leaf disorder, virus severity, virus loads and marketable yield. ‘La Estrella’ had the lowest number of whitefly adults per cm2 leaf area followed by all other butternut types (Genesis, Ultra HP, Waltham, Ceres, Atlas), and highest in ‘Tay Belle’, followed by ‘Table Ace’ and ‘Golden Hubbard’. We found significantly severe leaf silvering in ‘Golden Hubbard’ and ‘Sweet Mama’ followed by acorn types. We observed 100% virus incidence in all the varieties, however severity was lowest for ‘Ceres’, ‘Genesis’, ‘La Estrella’, ‘Sweet Mama’, ‘Ultra HP’ and ‘Waltham’. CCYV loads was found highest in ‘Sweet Mama’ and lowest in ‘Genesis’, ‘La Estrella, ‘Ceres’ and ‘Ultra HP’. CYSDV and CuLCrV loads were highest in ‘Table Ace’ and ‘Tay Belle’ and negligible in other varieties. We observed the highest marketable fruit yield in ‘Ceres’ (7,139 count/acre) and ‘Genesis’ (7,109 count/acre). Although ‘La Estrella’ was less infested with whitefly and WTV, it had poor fruit yields. Overall, we found butternut types mainly ‘Ceres’ and ‘Genesis’ as potential alternative cucurbit vegetable crops for fall production in southern Georgia with lower whitefly and WTV infestation resulting in the highest marketable fruit yields.
Speakers
NA

Nirmala Acharya

University of Georgia
Co-authors
DG

David G Riley

University of Georgia
NA
JC

Juan Carlos Diaz Perez

University of Georgia
MK

Manish Kumar

University of Georgia
NA
SB

Sudeep Bag

University of Georgia
NA
TM

Ted McAvoy

University of Georgia
NA
TC

Timothy Coolong

University of Georgia
Tuesday September 24, 2024 10:15am - 10:30am HST
South Pacific 2

10:15am HST

MKEC - Producer Awareness and Treatment of Ambrosia Beetle: Evidence from a Producer Survey
Tuesday September 24, 2024 10:15am - 10:30am HST
Ambrosia beetles are creating a larger negative impact on tree crops throughout the U.S. As such, research is on-going to better understand ambrosia beetles and the impact of varying treatment methods. However, little is known about awareness and the treatments currently being utilized by producers throughout the U.S. This research takes an in-depth look at producer awareness, treatments utilized pre- and post-ambrosia beetle infestation, and expenditures associated with treating ambrosia beetles. Utilizing a survey of producers throughout the U.S., most producers were aware of ambrosia beetles; however, treatments to control ambrosia beetles varied considerably. Interestingly, many producers chose not to treat, which implies many producers currently do not see a positive benefit/cost to treat. A reason for lack of treatment could be the lack of consistency of ambrosia beetle infestations as many producers indicated ambrosia beetles were not a problem each year. Further, this research does provide stakeholders with information on what treatment methods are preferred and means to increase information dissemination about new ambrosia beetle treatments.
Speakers
BC

Ben Campbell

University of Georgia
Co-authors
AR

Adam Rabinowitz

Auburn University
NA
AL

Alicia L Rihn

University of Tennessee
JC

Julie Campbell

University of Georgia
Tuesday September 24, 2024 10:15am - 10:30am HST
South Pacific 1

10:15am HST

NUR 1 - Micropropagation and production of Amur and Norway maple triploids
Tuesday September 24, 2024 10:15am - 10:30am HST
Acer ginnala (Amur maple) and A. platanoides (Norway) are trees that perform well under challenging urban and suburban conditions. Unfortunately, both are highly fecund and have escaped cultivation in several regions of the United States including becoming invasive. To address this, we have developed seedless triploids. To safely deploy seedless cultivars that present little or no ecological risk, they need to be on their own roots, as opposed to being budded onto seedling rootstocks, as was customary for Norway maple. Growing own-rooted plants prevents possible outgrowth of seedling rootstock. Amur maple roots well from stem cuttings but this is not feasible for Norway maple. Micropropagation presents a path forward both to increase propagules rapidly for initial introduction as well as a viable propagation method for the more recalcitrant Norway maple. Both species were successfully micropropagated and stage III plants were delivered in early April 2023. Plants were acclimatized and grown during the 2023 growing season to produce finished trade gallon whips. Material was variable in size because we effectively grew on everything without culling for inferior material. Both species were demonstrated to be amenable to micropropagation and their growth after acclimatization was better than expected. Micropagation will be further optimized, and as available material increases, size and production will be further standardized. This method will facilitate rapid introduction of seedless triploids and allow growers to be successful and profitable in production.
Speakers
RC

Ryan Contreras

Oregon State University
Tuesday September 24, 2024 10:15am - 10:30am HST
South Pacific 3

10:15am HST

PNM 1 - Effect of Bacterial Biostimulant Applied at Different N Rates in Potatoes
Tuesday September 24, 2024 10:15am - 10:30am HST
Nitrogen is a crucial macronutrient for potato production, as it plays a vital role in promoting photosynthesis, chlorophyll synthesis, and overall plant growth, ultimately contributing to higher crop yield. However, the shallow root system of potato plants and the sandy soil conditions in this region make applied nitrogen unavailable to the crop, resulting in reduced nitrogen use efficiency (NUE). An alternative and eco-friendly solution is to integrate microbial consortium inoculation in nutrient management plans. This approach entails the introduction of a mixture of beneficial microorganisms known as plant growth promoting rhizobacteria (PGPR), into the soil to promote plant growth. These N2-fixing microbes can increase soil N availability which could meet N demand of potato crop, hence can help in reducing N fertilizer input rate. Therefore, a commercial microbial biostimulant was applied with five different N rates 0, 78, 157, 235, and 314 kg ha-1. We found that microbial biostimulant did not increase tuber yield but improved NUE. Increasing N rate increased tuber yield, biomass and NUE significantly.
Speakers
LS

Lakesh Sharma

University of Florida
Dr. Lakesh Sharma is an assistant professor of soil fertility and sustainable agriculture at the University of Florida in Gainesville, FL. Lakesh has been farming since he was a child on his own farm. His academic school journey started in 2000. He is currently working on nutrient... Read More →
Co-authors
SS

Simranpreet Sidhu

University of Florida
NA
WD

Winniefred D Sharma

University of Florida
NA
Tuesday September 24, 2024 10:15am - 10:30am HST
Kahili

10:15am HST

POM 1 - Carbohydrate Status of Apple Fruitlets following Chemical Thinner Application Informs Sink Strength and Fruit Set
Tuesday September 24, 2024 10:15am - 10:30am HST
Crop load management of apple (Malus x domestica Borkh.) is one of the most important orchard management practices to ensure adequate fruit size and quality. Fruitlets are most sensitive to thinner applications early in the season, between 6mm and 20mm fruitlet diameter. During this time, abscission is associated with environmental and biological factors that influence fruitlet development, growth and sink strength. The carbohydrate economy of the fruitlet and its position within the cluster (king flower vs. lateral flowers) are primary factors contributing to the sink strength of individual fruitlets. We evaluated the relationship between the non-structural carbohydrate status of apple fruitlets in three different size classes (i.e., 90th, 50th, and 10th percentile of the population) and their respective likelihood to persist throughout the season. Persistence probabilities of these size classes were generated by an empirical fruit set prediction model based on the distribution of fruitlet mass and confirmed by actual measures of fruit set. Soluble carbohydrates and starch were quantified with an enzymatic assay procedure. Following chemical thinner application, the concentration of soluble sugars (glucose, fructose, sucrose, and sorbitol) was significantly reduced on a gram / gram fresh weight basis. Fruitlets in the 10th percentile generally had the lowest concentration of soluble sugars and starch and the slowest recovery rate following chemical thinner application. Fruitlets in the 90th percentile generally had the highest concentrations of soluble sugars and starch. Our data support that differences in the carbohydrate concentration of fruitlets contribute to their sink strength and abscission fate as predicted by a fruit set prediction model.
Speakers
LH

Laura Hillmann

Michigan State University
Co-authors
TS

Thomas Sharkey

Michigan State University
NA
TE

Todd Einhorn

Michigan State University
NA
Tuesday September 24, 2024 10:15am - 10:30am HST
Nautilus 1

10:15am HST

TCHG 1/ADMIN - FFAR Fellows: Opportunities for Horticulture PhD Students
Tuesday September 24, 2024 10:15am - 10:30am HST
The Foundation for Food and Agriculture (FFAR) Fellows Program was launched in 2018 and has become the premier professional development program for food and agriculture doctoral students. The FFAR Fellows offers leadership and professional development training for PhD students studying food and agriculture-related sciences in the U.S. and Canada. North Carolina State University leads the initiative, which provides Fellows with training, networking opportunities, and peer support. The objectives of the program are to 1) develop leadership competencies that enhance current and future individual productivity and well-being, and enhance Fellows capacity to contribute to the public good, 2) connect young scientists across research domains and geographic areas to promote multi-disciplinary understanding and problem-solving, and 3) broaden students understanding of their career options and create links to sectors beyond academia (industry, government, NGO). Over a 3-year period members of each cohort (25-30 Fellows) attend four in-person meetings plus monthly virtual sessions, create and execute annual professional development plans, and network and establish mentor-mentee relationships with industry scientists and others outside of academia. Eligible students are those who have completed their MS degrees before the program starts or current PhD students with at least three years remaining in the program. FFAR provides 50% of the funds with the rest matched from industry, NGOs, commodity organizations, or other sources of non-federal funds. Deadlines are generally late February for the Stipend Professional Development Category (providing professional development $50,000/year in support) and mid April for the Professional Development Category (providing professional development). Application requirements will be discussed in the presentation. The research program of each Fellow must address one or more of the six FFAR challenge areas, five of which relate to horticulture: Soil Health, Sustainable Water Management, Next Generation Crops, Urban Food Systems, and Health-Agriculture Nexus. Approximately 7% of the 139 Fellows are from horticulture programs. There are opportunities for more horticulture PhD students to take advantage of this program.
Speakers
JD

John Dole

North Carolina State University
Co-authors
RD

Rebecca Dunning

North Carolina State University
NA
Tuesday September 24, 2024 10:15am - 10:30am HST
South Pacific 4

10:15am HST

WCPM 1 - Optimizing Tomato Tolerance to Herbicides: Harnessing Biochar Herbicide Protection Pods for Enhanced Weed Control
Tuesday September 24, 2024 10:15am - 10:30am HST
Weed control is a significant challenge in tomato production, often resulting in considerable yield losses and compromised fruit quality. Common weeds in tomato cultivation, such as nutsedges, annual grasses, and Palmer amaranth, exacerbate this issue. With limited effective weed control options available, there's a critical need for an integrated approach that can alleviate weed pressure while safeguarding crop yield and quality. One promising solution is the utilization of biochar herbicide protection pods (HPPs). In our greenhouse trial, we evaluated the efficacy of HPPs in enhancing tomato tolerance to S-metolachlor and metribuzin herbicides. By incorporating activated carbon within the HPPs to shield crop plants from soil-active herbicides, which they marginally tolerate, we aimed to improve weed management effectiveness. Tomato seeds were encapsulated within four distinct HPPs: DFBC Cornstarch, DFBC Selvol, RHBC Cornstarch, and RHBC Selvol. Control tomato seeds without biochar were also included. Treatments were applied to tomato seedlings at the 2-3 leaf stage with S-metolachlor (1681.28 g/ha) or metribuzin (1120.85 g/ha), with visual injury evaluations conducted at 7, 14, and 21 days after application (DAA). Dry mass measurements were taken at 21 DAA, with an untreated control included for comparison. In the presence of metribuzin, three biochar treatments exhibited injury levels of around 70%, compared to a higher injury rate of 79% in the treatment without biochar. However, there was no significant difference in dry mass. Conversely, no discernible injury differences were noted among treatments with S-metolachlor, yet three biochar treatments demonstrated substantial enhancements in dry biomass. Specifically, treatments with biochar recorded notable increases in dry mass compared to those without biochar, indicating a 28 to 35% boost in biomass. These preliminary findings highlight the potential of biochar HPPs in enhancing crop health, yield, and weed management efficacy in tomato farming.
Speakers
TM

Te Ming Tseng

Mississippi State University
Co-authors
AC

Aricia Correa Ritter

Mississippi State University
NA
BB

Bailey Bullard

Mississippi State University
NA
DE

Dante Ellias

Mississippi State University
NA
Tuesday September 24, 2024 10:15am - 10:30am HST
Lehua Suite

10:30am HST

CE 1 - Interactions Between Blue Light and Far-Red Light on Growth of Culinary Herbs
Tuesday September 24, 2024 10:30am - 10:45am HST
Light quality can regulate growth and quality characteristics of young plants, but responses of culinary herb transplants are not well understood. Blue light generally inhibits extension growth while far-red light promotes stem elongation and leaf expansion. The objective of this study was to investigate the interaction between blue (400-499 nm) and far-red (700-750 nm) light on six culinary herb species, basil ‘Nufar’, cilantro ‘Santo’, parsley ‘Giant of Italy’, sage ‘Extraka’, mint ‘Spearmint’, and oregano ‘Greek’, with the goal of producing high-quality transplants with compact growth. Six indoor lighting treatments were tested with blue light photon flux densities (PFDs) of 20, 60, or 100 µmol∙m−2∙s−1 and far-red light of 0 or 60 µmol∙m−2∙s−1, with red light (600-699 nm) added so that the total PFD was 210 µmol∙m−2∙s−1 in all treatments. Seeds were sown in 72-cell trays at a constant 23 °C under a 16-h photoperiod and grown for 28-44 days until harvest. As expected, treatments with the highest far-red and lowest blue light PFDs had the greatest extension growth and those with no far-red and high blue light were the most compact. Preliminary results indicate basil, cilantro, and mint exhibited the greatest leaf area under high blue and far-red light. Generally, all species had the highest shoot fresh mass when grown with far-red light. We conclude that blue light and far-red light interact to regulate plant height and leaf area, especially in basil and sage. Therefore, including blue and far-red in the light spectrum should be considered to manage the morphology of young culinary herb plants.
Speakers
BK

Bridget Knight

Michigan State University
Co-authors
ER

Erik Runkle

Michigan State University
NA
Tuesday September 24, 2024 10:30am - 10:45am HST
Coral 1

10:30am HST

CHEX 1 - Evaluating Onsite Nitrate and Potassium Sensors
Tuesday September 24, 2024 10:30am - 10:45am HST
Destany Westlake, Paul Fisher, Josh Tebow, and Ryan Dickson Maintaining nutrient balance in hydroponic systems reduces the need to dump nutrient solution, thereby reducing water and fertilizer cost, and the resulting environmental impact. Laboratory testing to monitor nutrient concentrations is reliable, however it typically requires shipment and days to weeks of processing. The objective was to test the accuracy of handheld and inline ion-selective nitrate and potassium sensors compared with laboratory analysis of these nutrients. The methodology consisted of a factorial design with four reservoirs containing two water qualities and two fertilizer recipes with one nutrient film technique (NFT) system per reservoir. Nitrate and potassium concentration was measured twice per week during a 6-week hydroponic trial with basil, using handheld sensors, inline sensors, and Lachat QuickChem 8500 Series 2 analysis by a commercial horticulture laboratory. Based on the laboratory testing, NO3-N ranged from 142 to 272 mg.L-1 and K ranged from 111 to 271 mg.L-1 during the trial. The average error ± one standard deviation for the handheld sensor minus the laboratory concentration was -26.5 ± 18.8 mg.L-1 and -9.4 ± 13.1 mg.L-1 for N and K, and for the inline sensors was 3.5 ± 27.5 mg.L-1 and -15.2 ± 32.1 mg.L-1 for N and K, respectively. Therefore, we conclude that the handheld and inline sensors provided a useful and rapid estimation of N and K levels, but replicated samples should be taken and these levels should be verified by periodic laboratory analysis. Onsite testing could be an important tool for effective nutrient management to reduce nutrient loss and waste.
Speakers
DW

Destany Westlake

University of Florida
First- year Graduate Environmental Horticulture student.
Co-authors
JT

Josh Tebow

University of Arkansas
NA
PF

Paul Fisher

Floriculture Specialist at the University of FL
NA
RD

Ryan Dickson

University of Arkansas
NA
Tuesday September 24, 2024 10:30am - 10:45am HST
South Pacific 2

10:30am HST

MKEC - Consumer Awareness, Treatment Perception, and Purchasing Response to Flathead Borer
Tuesday September 24, 2024 10:30am - 10:45am HST
Flathead borers cause extensive damage for specialty crop producers throughout the U.S. As specialty crop producers attempt to mitigate damage, various treatments are being utilized. Furthermore, flathead borers cause damage in landscapes. To this end, this research examines the impact of consumer awareness and perception of flathead borer, consumer views on potential treatments in their landscape and in specialty crop production systems, and how the purchasing decision for a tree, bush, etc. might change given different probabilities of the tree, bush, etc. being impacted by flathead borer. An online survey on a representative sample of U.S. consumers conducted in 2024 found that there is little consumer awareness of flathead borer, but consumer’s recognized damage when shown pictures of what damage looked like. However, consumers had definitive opinions about flathead borer treatments, notably negative opinions about chemical treatments, though this view was heterogenous in nature. Finally, purchase decisions were impacted by the probability of a tree, bush, etc. being impacted, such that consumers were more accepting of a higher probability for minor damage, but a low probability of major damage would decrease the probability of purchase. From this research, stakeholders and researchers get a better understanding of which treatments may have a negative purchasing impact.
Speakers
BC

Ben Campbell

University of Georgia
Co-authors
AL

Alicia L Rihn

University of Tennessee
MD

Mounata Dahal

The University of Georgia
NA
Tuesday September 24, 2024 10:30am - 10:45am HST
South Pacific 1

10:30am HST

NUR 1 - Tea Plant Propagation for Nursery Production
Tuesday September 24, 2024 10:30am - 10:45am HST
Tea (Camellia sinensis) is the second most popular beverage worldwide and the U.S. annually imports 240 million pounds of tea. The limited availability of tea cultivars and limited knowledge for tea plant propagation are primary barriers for tea production in Washington and the U.S. overall. Time of year and section of shoot for propagation cuttings were tested in northwest Washington for tea cultivar Minto Pacific. Shoots were collected on 8 and 21 Sep, 6 and 24 Oct, 3 and 21 Nov, and 8 Dec 2022, and 18 Jan and 8 Feb 2023, then processed into top, mid, and bottom section cuttings. The bottom end of each cutting was scored (1-2 inches depth) using a knife, dipped into rooting hormone for 5-10 seconds, and placed into a treepot filled with propagation media (5:3:2 ratio peatmoss, vermiculite and perlite, pH 4.5) with the bottom node leaves resting on the mix line. Treepots were placed in a mist chamber with 50% shade and 70-80% relative humidity for 4 months. Survival rate was greatest for shoots collected from 21 Sep through 8 Dec 2022: 99.5% on average 4 months after collection. Cuttings from 8 Sep 2022 had the lowest survival rate overall: 77% at 4 months after collection. Top, mid and bottom section cuttings had an average survival of 96.7%, 95.8% and 94.7% at 4 months after collection. Plant height at 4 months after collection was greatest for cuttings collected on 8 Feb (6.6 cm) and lowest for all other dates (4.5 cm on average). Overall, cuttings from the mid and bottom sections had the greatest plant height at all times: average 5.0 cm at 1 month, average 5.1 cm at 2 months, average 5.2 cm at 3 months, and average 5.6 cm at 4 months. The number of new leaves measured in June 2023 was greatest for top and mid sections of the shoot (3.8 leaves on average) while the bottom section had the lowest number of new leaves (2.8 leaves on average). The overall health rating up to 4 months after collection was highest for cuttings collected on 6 and 24 Oct, and 8 Dec (more than 4.5 on average for all months). The top section of the shoot had the highest rating for overall health in all months (≥ 4.5). Keywords: Camellia sinensis, Cuttings, Northwest Washington, Vegetative
Speakers
CM

Carol Miles

Washington State University
Co-authors
SS

Srijana Shrestha

Washington State University
NA
Tuesday September 24, 2024 10:30am - 10:45am HST
South Pacific 3

10:30am HST

PNM 1 - Evidence of Downregulation in Atmospheric Nitrogen-Fixation Associated with Native Hawaiian Sugarcane
Tuesday September 24, 2024 10:30am - 10:45am HST
The study of nitrogen fixation in sugarcane has a long history that has demonstrated high potential but with substantial variation in results. This 32-month study sought to assess the response of nitrogen fixation associated with sugarcane (Saccharum officinarum L. cvs. ‘Akoki, Honua’ula, and ‘Ula) to available soil nitrogen. Plants were grown in large pots of perlite along with a fixing and a non-fixing plant control and administered liquid fertigation with varying amounts of isotopically enriched nitrogen. Assessment of nitrogen fixation utilized nitrogen isotope tracing and acetylene reduction assay in the target and control plants. Isotope enrichment and acetylene reduction assay both indicated that nitrogen fixation peaked under low nitrogen application, and declined with higher application rates, with agreement between the two methods. These results suggest that sugarcane engages in a downregulation of nitrogen fixation under high nitrogen availability, potentially explaining the high variation in published experimental results. This suggests that nitrogen management and fertilization strategy can impact the atmospheric inputs of nitrogen in sugarcane cultivation, and the potential to improve nitrogen application efficiency in cropping systems utilizing sugarcane.
Speakers
NL

Noa Lincoln

Associate Professor - Indigenous Crops, University of Hawaii at Manoa
Noa Kekuewa Lincoln is an Associate Professor with a focus on Indigenous Crops and Cropping Systems, in the College of Tropical Agriculture and Human Resources at the University of Hawai'i at Mānoa, and the PI of the Indigenous Cropping Systems Laboratory.  He is the President and... Read More →
Tuesday September 24, 2024 10:30am - 10:45am HST
Kahili

10:30am HST

POM 1 - Performance of a reflectance spectroscopy model to predict apple fruitlet thinning efficacy
Tuesday September 24, 2024 10:30am - 10:45am HST
Post-bloom apple chemical thinning relies on the application of plant bioregulators to induce fruitlet abscission, reducing crop load to improve fruit quality and promote return bloom. Abscission rates following chemical thinner application are influenced by carbohydrate status of the tree and thus widely variable. Multiple applications are often needed for growers to reach a desired crop load. However, trees are only perceptive to chemical thinners for a 3 to 4 week period shortly after bloom. Rapid prediction of chemical thinner efficacy is critical to allow growers to make necessary applications in this narrow period of time without the risk of over-thinning. In 2021 and 2022 a predictive model using reflectance spectroscopy measured with a handheld spectrometer (Felix F-750; Felix Instruments; Camas, WA, USA) was developed to predict chemical thinner efficacy for ‘Honeycrisp’ in North Carolina, USA. This model was found to predict chemical thinner efficacy with greater than 85% accuracy as early 3 days following a chemical thinner application. In 2023 and 2024 validation of this model occurred on multiple cultivars: ‘Red Delicious’, ‘Granny Smith’, ‘Gala’, and ‘Fuji’; and in multiple growing regions: Michigan, New York, and North Carolina, USA. Performance of the developed model to predict chemical thinning efficacy in this wide range of situations will be discussed to determine commercial applicability of the model.
Speakers
JL

James Larson

Utah State University
Co-authors
LH

Laura Hillmann

Michigan State University
LG

Luis Gonzalez Nieto

Cornell University
NA
TR

Terence Robinson

Cornell University
NA
TK

Thomas Kon

North Carolina State University
NA
TE

Todd Einhorn

Michigan State University
NA
Tuesday September 24, 2024 10:30am - 10:45am HST
Nautilus 1

10:30am HST

TCHG 1/ADMIN - Nurturing Knowledge: The Impact of Assuming Professional Role in Achieving Learning Objectives in Upper-Level Horticulture Courses
Tuesday September 24, 2024 10:30am - 10:45am HST
Practical experience is invaluable to students majoring in plant-related fields including horticulture. Most times students with no prior practical experience acquire the required knowledge and skills to succeed in horticulture field through college education. However, there is limited literature on the impact of courses implementing experiential learning through students assuming horticulture-related professional roles on achieving learning objectives. Hence, the current study investigated the pedagogical approach of practical learning by incorporating students undertaking management role in achieving learning objectives of upper-level horticulture courses within a classroom setting. The methodology involves implementing this student-centered activity of assuming professional role as greenhouse manager and hydroponics operation manager in two different 3000-level courses (urban horticulture and hydroponics and soilless crop production, respectively) and assessing their impact on learning outcomes. Each student assumed the role of manager for a week and experienced real-world problem solving in greenhouse and hydroponics operation management settings. Quantitative and qualitative data collection methods, including surveys, and observational analysis, are utilized to evaluate the effectiveness of the approach in enhancing students' understanding and attainment of course objectives. Preliminary findings indicate that incorporating assumption of horticulture professional role activities fosters deeper engagement, critical thinking, and practical application of theoretical concepts. Students reported increased confidence in their abilities to apply learned principles in real-world scenarios, as well as a greater appreciation for the complexities of urban horticulture and hydroponics crop production. Overall, this research highlights the potential of experiential learning strategies, such as horticulture professional role simulations, to effectively support the achievement of learning objectives while providing students with valuable insights into professional practice. Finally, the findings contribute to the ongoing discourse on innovative pedagogical approaches and their impact on student learning outcomes in higher education settings.
Speakers
SK

Shivani Kathi

Assistant Professor, Oklahoma State University
Tuesday September 24, 2024 10:30am - 10:45am HST
South Pacific 4

10:30am HST

WCPM 1 - Evaluation of Plant Hormones and Other Seed Treatments to Reduce Injury Caused by Preemergent Herbicides on Direct-seed
Tuesday September 24, 2024 10:30am - 10:45am HST
Poor competitive ability and limited herbicide options make weed management of Brassica crops difficult. Growers often adopt the use of transplants, which is less efficient in terms of time, material, and labor when compared with direct seeding, resulting in higher prices per unit. Seed treatment with protective compounds could decrease crop injury from preemergent (PRE) herbicides making it profitable to direct-seed Brassica plants for production. Research was conducted to evaluate the ability of three candidate safeners [24-epibrassinolide, melatonin, and ascorbic acid (AsA)] to reduce injury caused by four herbicides (S-metolachlor, pyroxasulfone, halosulfuron, and mesotrione) applied PRE on the collard green cultivar Top Bunch and turnip cultivar Purple Top White Globe. Two independent greenhouse trials were conducted at the Clemson University Coastal Research and Education Center in Charleston, SC. Visual injury of the treated plants was evaluated weekly and dry mass was collected 21 days after treatment. Seed treatment did not reduce injury efficiently caused by pyroxasulfone, halosulfuron, and mesotrione; all doses were lethal for both crops. However, collard seeds treated using melatonin and AsA had 66% and 54% less injury caused by S-metolachlor at 514 g⋅ha–1 a.i., respectively. On turnips, melatonin was the only treatment that reduced the S-metolachlor damage on seedlings, with 43% less injury than untreated seedlings. Plant injury and plant weight correlated significantly for both Brassica crops. The reduction in injury caused by S-metolachlor when seeds were treated with melatonin and AsA validated those compounds’ protective ability. Seed treatment with melatonin could be combined with PRE applications of S-metolachlor to overcome the low weed competitive ability of these species early in the season.
Speakers Co-authors
SB

Sandra Branham

Clemson University
NA
Tuesday September 24, 2024 10:30am - 10:45am HST
Lehua Suite

10:30am HST

Building Your Personal Brand with Surfing Style: Workshop 3
Tuesday September 24, 2024 10:30am - 11:30am HST
In this workshop section, we'll delve into the essential strategies for students and early career professionals looking to establish their professional brand. Crafting a distinct identity is crucial in today's competitive job market, and we'll explore techniques tailored to graduate students' unique experiences and aspirations. From honing your elevator pitch to leveraging your academic accomplishments, we'll cover the fundamental elements of personal branding. Additionally, we'll delve into the increasingly vital role of social media platforms in shaping professional reputations, offering insights on how to navigate and optimize these channels effectively. Whether you're aiming for a career in academia or industry, this workshop will equip you with practical tools to kickstart your journey toward building a compelling professional presence.
Speakers

Tuesday September 24, 2024 10:30am - 11:30am HST
Coral 3

10:30am HST

Viticulture and Small Fruit Interest Group Meeting
Tuesday September 24, 2024 10:30am - 11:30am HST
Moderator
AA

Amaya Atucha

University of Wisconsin Madison
Tuesday September 24, 2024 10:30am - 11:30am HST
Sea Pearl 4

10:45am HST

CE 1 - Blue and Green Light and Temperature Interactively Regulate Growth, Morphology, Physiology, and Phytochemicals of Lettuce
Tuesday September 24, 2024 10:45am - 11:00am HST
Substituting green (G; 500-600 nm) for blue (B; 400-500 nm) light can enhance crop yield through increasing leaf expansion and photon capture in indoor farming. In addition to yield, the concentration of phytochemicals may also be influenced by varying B to G light ratios. Those responses to B and G light are primarily mediated by cryptochrome photoreceptors. However, cryptochrome activity is further dependent on temperature. We hypothesized that B and G light and temperature could interactively regulate plant morphology, physiology, and secondary metabolites, consequently impacting crop yield and nutritional quality. Two cultivars of lettuce (Lactuca sativa L.), ‘Rouxai’ and ‘Rex’, were grown under three temperatures (20, 24, and 28 ℃) and five spectral treatments composed of B, G, and red (R; 600-700 nm) light (B40G0R60, B30G10R60, B20G20R60, B10G30R60, and B0G40R60). The subscript number following each light type represents its percentage in total photon flux density (TPFD; 400-800 nm). TPFD was maintained at a constant level of 200 μmol·m-2·s-1, with R photon flux of 120 μmol·m-2·s-1 (60% of TPFD) in all treatments. Results revealed that light spectra and temperature interactively influenced plant morphology. Specifically, in Rouxai, increasing G light from 0% to 40%, coupled with decreasing B from 40% to 0%, linearly increased total leaf area at all three temperatures. Notably, the substitution of G for B light caused the greatest leaf expansion at 24 ℃ (a 64% increase at 20 ℃, a 90% increase at 24 ℃, and a 32% increase at 28 ℃). In Rex, substituting G light for B light up to 30% increased total leaf area at 20 and 24 ℃, but not at 28 ℃. Similar to Rouxai, the spectral effect on the leaf expansion of Rex was greater at 24 ℃, compared to 20 ℃. Shoot dry weight responded to spectral and temperature treatments similarly as total leaf area. Secondary metabolites (e.g., phenolics and flavonoids) and antioxidant capacity consistently decreased with increasing G light (or decreasing B from 40% to 0%), but the decline was more pronounced at warmer temperatures. Without significant interaction between light spectrum and temperature, chlorophyll and carotenoid contents decreased with increasing G light. Thus, we concluded that the proportion of B and G light and temperature interactively regulated plant morphology and secondary metabolites, ultimately affecting crop yield and nutritional quality. Our study emphasizes the importance of considering the interaction between light spectrum and temperature in optimizing production systems.
Speakers Co-authors
Tuesday September 24, 2024 10:45am - 11:00am HST
Coral 1

10:45am HST

CHEX 1 - Filling the Gaps for Informed Adoption of Carolina Strong Back Grafted Nursery: Transplanting Time and Spacing Optimization
Tuesday September 24, 2024 10:45am - 11:00am HST
Grafting is an effective management strategy in watermelon crop against soil borne pathogens. Carolina strongback (SB) rootstock used for grafting, is resistant to both fusarium wilt and root knot nematodes which are devastating soil borne pest of watermelon. In addition, recent studies have shown higher vigour of SB grafted plants than regular nursery plants. However, grafted watermelon nursery is 4-5 times more expensive than regular nursery which leads to reluctance among farmers for adoption of this effective management strategy. Further, recent trials showed that grafted plant bear fruits 7-10 days later than regulate plants leading to farmers losing early profitable watermelon market. To fill these gaps for informed adoption of SB grafted nursery, a field experiment was conducted at Blackville SC with the objective to evaluate the optimum transplanting time and density of SB grafted watermelons nursery to have equivalent fruit yield and harvesting window to that of regular nursery. The experiment comprised of three transplanting times and four transplant densities in a split plot design. We will evaluate the impact of transplanting time and transplanting density on watermelon fruit yield, fruit quality, number of fruits per plant, periodic fruit harvesting yield and plant vigour.
Speakers
SK

Sukhman Kaur

Clemson University
Co-authors
BJ

Bhupinder Jatana

Clemson University
TS

Tom Sanders III

Clemson University
NA
Tuesday September 24, 2024 10:45am - 11:00am HST
South Pacific 2

10:45am HST

MKEC - Market Research to Reinvigorate the Processed Vegetable Industry using Consumer Sensory Evaluations
Tuesday September 24, 2024 10:45am - 11:00am HST
In an effort to understand perceived quality and purchase interest in processed frozen vegetables vs. their fresh counterparts, consumer sensory evaluations were conducted with Oregon consumers (n=108, 68% female, aged 18 and over). Consumers were served blind coded samples to investigate consumer preference for fresh vs. frozen select processed vegetables in appearance, aroma, color, overall liking, flavor, and texture. Utilizing hedonic scales and just-about-right methodology, consumers both rated their liking for each and assessed the ideal sweetness, texture, and moisture content. Additionally, the survey was used to probe the best strategies for increasing consumer awareness and marketability of processed vegetables and to understand consumer purchasing behavior and motivation when it relates to buying processed vegetables. Consumers also responded to questions about quality, purchase intent and ideal packaging size for processed vegetables. Consumer perception of frozen processed broccoli, while not as high as fresh, was positive. When asked about the characteristics of produce that most influence their purchasing decisions, quality and freshness were the two most important considerations to these consumers. Seventy-five percent responded either yes or depends on the price when probed about their interest in a frozen vegetable and fruit consumer supported agriculture (CSA) model. Consumers were also asked which reasons would most convince them to join a frozen vegetable and fruit CSA. The most frequently chosen options were 1) to support the livelihoods of growers and their communities, 2) frozen produce reduces waste and 3) frozen produce tastes fresher than off season produce. These ideas could be leveraged to encourage consumers to support the purchase of processed frozen vegetables as well as support a subscription service to high quality frozen produce.
Speakers
AC

Ann Colonna

Oregon State University Food Innovation Center
Co-authors
EP

Edward Peachey

Oregon State University
NA
JM

James Myers

Oregon State University
Tuesday September 24, 2024 10:45am - 11:00am HST
South Pacific 1

10:45am HST

NUR 1 - Establishment of Fraser Fir Christmas Tree Plantations in Response to Mulch and Root Dips
Tuesday September 24, 2024 10:45am - 11:00am HST
In the Great Lakes region of the United States Christmas tree plantations are established by planting seedlings or transplants. Reducing plant moisture stress after planting is crucial to successful establishment of these small conifers. A myriad of products have been marketed to Christmas tree producers with claims to improve transplant success by limiting transplant shock. Since 2021, we have conducted a series of field trials in collaboration with Michigan Christmas tree growers to evaluate the effect of root dips, mulching and other cultural practices on transplant survival and growth. Root dip products applied immediately prior to planting included: DieHard™ Root Dip (endo/ecto mycorrhizae polymer), MycoApply® Injector Ecto (ectomycorrhizae), SoilMoist™ Fines, and Roots® Terra-Sorb® Fine Planting Gel (polymer). Cultural treatments that were applied following planting included: foliar antitranspirant spray (Wilt-Pruf® [25% di-1-p-menthane]), wood chip mulch, shade blocks (20.3 cm x 30.5 cm mesh screen), controlled release fertilizer, and biochar. Root dips did not affect tree survival or growth in any of the trials. Mulch and shade blocks increased shoot growth at several farms. Improved survival of trees under mulch was associated with improved soil moisture. Mulch did not affect foliar nitrogen (N) concentration, indicating that mulch did not ‘tie-up’ N. The application of Wilt-Pruf reduced transpiration but also reduced photosynthetic rate, resulting in a net decrease in shoot growth. Fertilization at planting significantly reduced survival on two of four sites. Overall, the results suggest that cultural treatments, especially mulch, are more likely to improve plantation establishment than root dips.
Speakers
BC

Bert Cregg

Michigan State University
Dr. Bert Cregg is a professor of Horticulture and Forestry at Michigan State University. He conducts research and extension programming on the physiology and management of trees in landscapes and nursery and Christmas tree production.
Co-authors
RJ

Riley Johnson

Michigan State University
NA
Tuesday September 24, 2024 10:45am - 11:00am HST
South Pacific 3

10:45am HST

PNM 1 - Nitrate Leaching Potential of UAN and Organic Soybean Extract Fertilizers Applied to Lettuce
Tuesday September 24, 2024 10:45am - 11:00am HST
In California, lettuce (Lactuca sativa) production generates over $1.8 billion in revenue. As a leafy green vegetable, Nitrogen (N) fertilizer applications can reach as much as 280 kg N/ha. The relative shallow root systems and frequent irrigation can enhance Nitrate (NO3) Leaching Potential (NLP) when the crop is grown on Sandy Loam soil. Because of economic, health, and environmental concerns, growers are exploring the option of using organically approved fertilizers such as water-soluble N derived from soy protein hydrolysate (GS) as an alternative to Urea Ammonium Nitrate (UAN). The objective of this study was to compare the NLP of equivalent rates of UAN and GS applied to a (1) soil-column study (Phase 1) and (2) greenhouse lettuce crop with 3 Irrigation regimes x 2 Fertilizers x 4 Rates as a factorial experiment replicated four times (Phase 2). In the Phase 1 study, approximately 2,150 ml of water containing a chloride (Cl) tracer and fertilizers at rates of 0, 56, 112, and 168 kg N/ ha were applied to a fixed volume of soil at a bulk density of 1.35 g/cm3. The chloride concentrations in the leachate from both fertilizer treatments were similar, and the water balance accounted for 95% of the solution applied. The concentration and amount of NO3 in the leachate collected from soil treated with GS were lower or at least equal to that obtained from the soils treated with UAN. In contrast, the amount of residual soil NO3 was significantly higher in the soil receiving the UAN, ranging from 2 to 4 times as the application rates increased from 56 to 168 kg N/ha, respectively, implying a relatively higher NLP for the UAN. In the case of the lettuce experiment (Phase 2), there were no significant differences in the chlorophyll content based on the choice of fertilizer or application rates. Lettuce yields, expressed on a dry matter basis, were not significantly (p=0.11) different for fertilizer type, with similar fertilizer rate response curves being obtained for both UAN and GS. Finally, the mean %N and %C in the lettuce leaves were 3.22% and 40%, respectively, regardless of whether the lettuce was grown with synthetic UAN or organically derived soybean hydrolysate (GS). These preliminary findings justify the need to investigate further the impact of higher irrigation rates and even saturated conditions on the NLP of vegetables subjected to the two fertilizers used in the current study.
Speakers
avatar for Dave Goorahoo

Dave Goorahoo

Professor, California State University, Fresno
Co-authors
FC

Florence Cassel S

California State University, Fresno
GS

Govind Seepersad

The University of the West Indies- Trinidad
NA
KG

Konner Gilman

California State University, Fresno
NA
WC

Wesley Chun

Grower's Secret Inc.
NA
Tuesday September 24, 2024 10:45am - 11:00am HST
Kahili

10:45am HST

POM 1 - Overexpression of the Coding Sequence of Ma1 Decreases Fruit Acidity in ‘Royal Gala’ Apple
Tuesday September 24, 2024 10:45am - 11:00am HST
Vacuolar accumulation of malic acid, the predominant organic acid in apple (Malus domestica) and many other fleshy fruits, largely determines fruit acidity, a key trait for fruit taste and flavor. ALUMINUM-ACTIVATED MALATE TRANSPORTER 9 (ALMT9/Ma1) underlies a major genetic locus, Ma, for fruit acidity in apple. A natural mutation at base 1455 leads to a pre-mature stop codon that truncates the Ma1 protein by 84 amino acids to ma1, and this truncation significantly reduces Ma1’s malate transport activity by disrupting a conserved C-terminal domain, leading to low fruit acidity in recessive homozygous ma1ma1 genotypes. However, it remains unclear how Ma1 functions to transport malate across the tonoplast membrane. When the coding sequence of Ma1 was overexpressed in ‘Royal Gala’ apple (Ma1ma1) to determine its in planta function, to our surprise, the transgenic fruit had drastically reduced fruit acidity compared with the wild-type (WT). This led us to uncover that Ma1 undergoes alternative splicing. Two isoform proteins are generated by alternative splicing: Ma1beta being 68 amino acids shorter with much lower expression than the full-length protein Ma1alpha. Ma1beta does not transport malate itself, but interacts with the functional Ma1alpha, creating synergy with Ma1alpha for malate transport in a threshold manner when Ma1beta is equal to or exceeds 1/8 of Ma1alpha. In WT ‘Royal Gala’, Ma1 operates at this threshold. Overexpression of Ma1alpha triggers feedback inhibition on the native Ma1 expression via transcription factor MYB73, decreasing the Ma1beta level well below the threshold that leads to significant reductions in Ma1 function and malic acid accumulation in fruit. Overexpression of Ma1alpha and Ma1beta or genomic Ma1 increases both isoforms proportionally and enhances fruit malic acid accumulation. These findings reveal an essential role of alternative splicing in Ma1-mediated malate transport underpinning apple fruit acidity.
Speakers
LC

Lailiang Cheng

Cornell University
Co-authors
CL

Chunlong Li

Cornell University
NA
KX

Kenong Xu

Cornell University
NA
MZ

Mengxia Zhang

Cornell University
MP

Miguel Pineros

Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University
NA
SK

Srinivasan Krishnan

Cornell University
NA
Tuesday September 24, 2024 10:45am - 11:00am HST
Nautilus 1

10:45am HST

TCHG 1/ADMIN - Mid-semester Teaching Evaluations to Enhance Course Communication
Tuesday September 24, 2024 10:45am - 11:00am HST
Effective course communication is critical to foster a positive learning environment. One way communication can be improved is by scheduling a mid-semester teaching evaluation to capture student perspectives on what aspects of the course are going well and what could be improved. By providing students with a platform to express their opinions mid-semester, instructors have access to timely feedback to improve their teaching methods while the course is still ongoing. In this study, a mid-semester evaluation was conducted in an asynchronous, online Fruit Production course with 27 undergraduate students and one graduate student. The students were given a link to an online survey to respond to specific questions about the course structure and an open-ended question for actionable feedback. The evaluations were voluntary, anonymous, and confidential to solicit honest student responses. By having students respond individually, it was possible to capture unique student viewpoints and consensus statements among the class with a 96% response rate. Students responded positively to some aspects of the course such as the use of hands-on assignments; however, course modifications were made only in response to critiques. The most notable feedback was 14.8% of the students responding that the course material did not feel manageable with 44.4% of the class spending more than the expected time on lecture assignments. Additionally, students requested more clarity on the assigned projects. The survey responses were summarized for the students along with specific ways the course would be adjusted to better meet the student's needs and enhance their learning experience. To address the students’ concerns, the course workload was reduced, and students were provided with a clear explanation of their expected level of engagement. Recorded instructions along with detailed written descriptions and templates of the projects were also provided to aid in transparency about course assignments. Overall, students were well receptive of the mid-semester evaluation and reported it improved their satisfaction with the course. Because students found the mid-semester evaluation valuable to their learning, the course modifications will be maintained for future semesters.
Speakers
RM

Rebekah Maynard

University of Georgia
Tuesday September 24, 2024 10:45am - 11:00am HST
South Pacific 4

10:45am HST

WCPM 1 - Flaming, Cultivation, and Handweeding Weed Control in Organic Carrot Production Systems with Different Fertilizer Types
Tuesday September 24, 2024 10:45am - 11:00am HST
Weed management is a common weed management practice in organic weed control, however, this practice is expensive. Other integrated weed management practice could include flaming and cultivation. The study objective is to investigate flaming, cultivation, and hand weeding to develop an integrated weed control program in organic carrot. The study was conducted in an organic certified field at the North Florida Research and Education Center Suwanee County, Live Oak, FL. Treatments were a factorial design with 5 weed management programs and 2 fertilizer types. Weed management treatments were (1) flaming preseeding weekly cultivation, (2) flaming preseeding weekly cultivation 1 handweeding event, (3) flaming preseeding flaming preemergence weekly cultivation (4) flaming preseeding flaming preemergence weekly cultivation 1 handweeding event, (5) flaming preseeding flaming preemergence weekly cultivation 2 handweeding events. Fertilizer treatments were pelleted poultry litter and 50% feather meal 50% poultry litter. Carrot ‘Uppercut’ were seeded on December 3, 2020 and were harvested on May 3, 2021. Eight rows of carrot were planted on a 0.9 m bed top. Fertilizer was applied immediately after seeding. Weeds were counted by species in two 0.5 m2 quadrats prior to each basket weeder cultivation between the rows. Carrots were cultivated 6 times before the carrot were too large and would be injured. Fertilizer type were not different for weed counts at all dates. Cutleaf evening primrose (Oenothera laciniata) was the only weed species in the plots from the beginning of the trial through harvest. The inclusion of flaming preplant and preemergence delayed the emergence of cutleaf evening primrose, however at 6 weeks after planting all the treatments were similar. Mid-season weed species included henbit (Lamium amplexicaule) and common chickweed (Stellaria media), however, these weed species were not present late-season. Purple toadflax (Linaria purpurea) and old world diamond flower (Oldenlandia corymbosa) were the most common weed species late-season. Single handweeding had excellent control early-season, but two handweeding events controlled both the cool and warm season weeds. Early season weed control should include flaming. Between row weed management was best with cultivation. Handweeding is necessary for late season weed control when flaming and cultivation are not available.
Speakers
PD

Peter Dittmar

University of Florida
Co-authors
DT

Danielle Treadwell

University of Florida
NA
GM

Gabriel Maltais-Landry

University of Florida
NA
Tuesday September 24, 2024 10:45am - 11:00am HST
Lehua Suite

11:00am HST

Exhibitor Talk: Bridging Metabolomics and Proteomics for Plant Research
Tuesday September 24, 2024 11:00am - 11:15am HST
Metware Biotechnology Inc.
Speakers
SJ

Sneha Jeevan

Metware Biotechnology Inc.
Tuesday September 24, 2024 11:00am - 11:15am HST
Coral 5

11:00am HST

CE 1 - Switching From Low to High Blue Light Before Harvest Increases Nutritional Quality While Maintaining High Biomass in Red-leaf Lettuce Under Elevated CO2
Tuesday September 24, 2024 11:00am - 11:15am HST
Growing food crops in space supports astronauts’ dietary needs in long-duration space missions and necessitates efficient use of light. In red-leaf lettuce (Lactuca sativa), sufficient red (R) and far-red (FR) light promote extension growth, whereas sufficient blue (B) light restricts extension growth but enhances secondary metabolite accumulation. Green (G) light also contributes to photosynthesis and improves visual quality. Compared to fixed light spectra, we evaluated dynamic light spectra to balance harvestable biomass and nutritional quality of red-leaf lettuce ‘Outredgeous’ under elevated CO2 concentration (≈2794 μmol⋅mol–1) and intermediate relative humidity (≈48%), typical on the International Space Station. This ground-based growth chamber experiment was performed twice following a randomized complete block design. We grew plants hydroponically at ≈22 °C under light-emitting diodes (LEDs) with four fixed light spectra and four dynamic light-spectrum alternations. The four fixed light spectra from seed to harvest were B60R140, B10R190, B10G50R140, and B10R140FR50 (the subscript following each waveband denotes its photon flux density in μmol·m−2·s−1). The four dynamic light-spectrum alternations switched among B10R190, B10G50R140, and B10R140FR50 in the lag (day 0–11) and exponential growth (day 11–25) phases, followed by B60R140 in the finish phase (day 25–28). Plant data were collected 11 and 28 days after sowing for seedlings and mature plants, respectively. Among the fixed light spectra, increasing the B photon flux density decreased shoot mass by 28% to 39% but increased total phenolic concentration by 27% to 45% in mature plants. Partial substitution of R light with G light decreased shoot mass by 31% to 42% in seedlings, but not mature plants. Partial substitution of R light with FR light did not influence shoot mass of seedlings or mature plants. Compared with fixed low B light treatments, dynamic light-spectrum alternations with high B light in the finish phase did not affect shoot mass, root mass, or leaf number while increasing total phenolic concentration by 8% to 25%. In addition, partial substitution of R light with G or FR light during the lag or exponential growth phase did not influence shoot or root mass. We conclude that low B light in the lag and exponential growth phases followed by short-term high B light in the finish phase improves lettuce nutritional quality without decreasing biomass as seen under long-term high B light. Spectrum selection in the earlier phases should prioritize the photosynthetic photon efficacy of LEDs to maximize light use efficiency.
Speakers
SM

Shem Msabila

University of Delaware
Co-authors
QM

Qingwu Meng

University of Delaware
Tuesday September 24, 2024 11:00am - 11:15am HST
Coral 1

11:00am HST

CHEX 1 - Substrate Hydro-Physical Properties in Soilless Agriculture: Investigating the Role of Container Geometry on Substrate Air and Water Profiles
Tuesday September 24, 2024 11:00am - 11:15am HST
The cultivation of specialty crops in soilless growing systems has emerged as a pivotal practice in modern agriculture. The adoption of container-based production, particularly through soilless culture systems, is witnessing a significant uptrend among specialty crop producers. The challenges associated with cultivating plants in containers are extensively documented, particularly in navigating the delicate balance between insufficient and excess water. Shallow containers often result in excessive water, limiting air availability, while the confined volume of containers imposes restrictions on the water supply for optimal plant growth. Air and water capacity (AWC) model was utilized to determine basic physical properties, such as total porosity (TP), air space (AS), and container capacity (CC), for a substrate in specific-sized and shaped containers. AWC models offer a comprehensive tool for estimating hydrophysical properties across multiple substrate/container combinations simultaneously. The existing literature lacks direct reporting on these specific container types, primarily focusing on modeling the air and water profiles of traditional containers that the floriculture industry utilized, leading to a notable gap in data concerning the dynamic interplay between air and water profiles within these containers and their impact on the rooting environment. 19 substrates and 30 commercially used container selections were modeled to understand their air-water profiles. The results underscore the effect of container geometry on substrate air-water profiles, necessitating different management approaches for the same substrate in different containers. Container height stands out as a critical factor, exerting a substantial influence on substrate characteristics and subsequently affecting air and water values.
Speakers
BS

Brandan Shur

North Carolina State University
Co-authors
BJ

Brian Jackson

North Carolina State University
NA
WF

William Fonteno

North Carolina State University
NA
Tuesday September 24, 2024 11:00am - 11:15am HST
South Pacific 2

11:00am HST

MKEC - Perceptions and Climate Change Adaptation Behavior Among New Mexico's Specialty Crops Growers
Tuesday September 24, 2024 11:00am - 11:15am HST
Every year, climate change causes $73 million in loss to New Mexico’s agriculture (Niemi, 2009), and despite the numerous incentivizing conservation programs, the state remains one with the lowest adoption rates in the nation (Wade et al., 2015). Thus, understanding specialty crop growers’ perceptions of climate change is a crucial element to develop mitigation strategies that will ensure resiliency of the state’s agriculture. Thus, in this study, we use survey data of 300 farmers from New Mexico to: (a) determine how they perceive climate change; (b) assess their awareness of incentivizing conservation programs; and (c) elicit their willingness and how they would adapt their daily behavior (e.g. recycling, waste management), and agricultural practices (e.g. reduced tillage, cover crops, nitrogen management) to climate change. Three main hypotheses are tested in this study: (H1): Climate change perceptions are equally influenced by demographic characteristics and peer-counseling; (H2): Farmers lack literacy regarding climate change incentivizing programs. And, (H3): Farmers who perceive climate change are more likely to adapt. Descriptive statistics are used to test (H1), while for H2 and H3, a sample selection model is needed to study adaptation willingness among climate change believers. The study uses Heckprobit models to address sample selection bias that may occur if the “don’t believe” respondents were excluded from the estimation. We estimate two models, one for the daily behavior adaptation, and one for agricultural activity adaptation. Two equations per model are then, estimated where both dependent variables are dichotomous: (y_1i), the selection equation that evaluates the probability that grower i believes in climate change, taking the value of one when it’s the case, and takes the value of zero if otherwise. (y_2i), the probit equation that elicits grower i’s willingness to adapt, equals one when the grower is willing to adapt, and zero otherwise. We consider attitudes toward sustainability, land attachment, familiarity with conservation programs, information means (how the grower informs himself on conservation practices), and demographics, as factors for the equations. All estimations will be carried out by the likelihood method using STATA. We expect that growers who perceive climate change will be more likely to change their behavior as well as adopting conservation practices to accommodate climate change. Understanding conservation practices adoption preferences in the state, will help improving the design of adaptation policies to better fit climatic conditions and growers’ needs.
Speakers
SB

Sawssan Boufous

New Mexico State University
Co-authors
BH

Brian Hurd

New Mexico State University
NA
Tuesday September 24, 2024 11:00am - 11:15am HST
South Pacific 1

11:00am HST

NUR 1 - Cultivating Control: Effective Suppression Methods for Jumping Worms in Container Nursery Production
Tuesday September 24, 2024 11:00am - 11:15am HST
Keywords: Amynthas spp., Biological Controls, Invasive Species, Soil Health, Temperate Ecosystems Jumping worms (Amynthas spp.) present a significant threat to biodiversity and overall soil health across temperate ecosystems. In forest systems, jumping worms alter ecological dynamics by impacting the organic litter layer, soil structure and chemistry, food web functionality, and nutrient cycling processes. These annual, hermaphroditic worms reproduce through parthenogenesis and inhabit the top few inches of moist soils. They survive extreme temperatures in their cocoon stage with the possibility of remaining dormant for several growing seasons. One inadvertent method of jumping worm spread is through container-grown nursery stock and horticultural substrates. In nursery production, jumping worms modify plant quality by consuming organic matter such as roots, altering substrate structure and chemistry in the container, and contributing to excessive nutrient leaching. The rapid movement of these worms may also impact consumer buying potential and preference. There are currently no products listed for controlling jumping worms in the United States, leading to challenges with the management of their spread. We hypothesize that control methods not yet listed for jumping worms in the United States have the potential to effectively suppress jumping worm populations in container-grown crops. Our objective was to further evaluate chemical and biological approaches for managing jumping worms in container nursery production systems. Treatments included a non-treated control, BotaniGardⓇ (2 Tbsp/gal), Thiophanate-methyl fungicide (0.625 mL/400mL), Sodium lauryl sulfate (2 mL/L ), Cedarwood oil (1.5625 mL/L), ConserveⓇ (0.317 mL/400mL), Castaway 3-0-1 Tea Seed Meal Fertilizer (2.7 g/pot), Slug MagicTM (0.5 oz/pot), and SevinⓇ (8.75 mL/400mL). The results of this work suggest differential efficacy between treatments and highlight options with potential for application in horticultural production. Identifying effective control methods benefits the scientific community and the horticultural industry by providing a foundation for future research activities centered on jumping worm management as well as limiting their spread through horticultural products. These findings support growers by outlining potential management practices that demonstrate efficacy for controlling jumping worms in the Amynthas genus.
Speakers
avatar for Jenna Simon

Jenna Simon

Research Assistant, University of Minnesota - Twin Cities
Jenna Simon studies invasive jumping worms (Amynthas spp.) with a focus on containerized production. She has a strong passion for the nursery profession and strives to bridge the gap between horticulture and ecology. She believes that ecology should be viewed from many different lenses... Read More →
Co-authors
BM

Brandon Miller

University of Minnesota - Twin Cities
EB

Erin Buchholz

University of Minnesota
NA
JG

Josef Gorres

University of Vermont
NA
MN

Maryam Nouri Aiin

University of Vermont
NA
Tuesday September 24, 2024 11:00am - 11:15am HST
South Pacific 3

11:00am HST

PNM 1 - Evaluating the N Status of Tomato Supplied with Soluble and Controlled-release Urea Formulations
Tuesday September 24, 2024 11:00am - 11:15am HST
Matching crop nitrogen (N) demand and supply is necessary to increase crop N use efficiency (NUE) and reduce environmental impact. Proximal optical sensors such as the Soil Plant Analysis Development (SPAD) meter have been found to be useful in monitoring the crop N status, providing insight into the effects of N fertilization practices in cropping systems. High N rate applications are common in conventional tomato production, where loss of N, more specifically NO 3 - , from the rootzone can decrease water quality. Thus, optimal N management of fertigated vegetable crops requires frequent and rapid assessment of the crop N status to quickly adjust application of N when required. A two-year field study was conducted in north Florida to evaluate the crop N status based on N fertilization practices associated with soluble urea and polymer coated controlled-release urea (CRU) for fall and spring tomato (‘HM 1823’) grown in sandy soils under a plastic-mulched bed system. In addition to a no N fertilizer treatment, three urea N sources [one soluble source and two polymer-coated CRU sources with different N release durations of 60 (CRU-60) and 75 (CRU-75) days] were applied at three N rates (140, 168, and 224 kg ha -1 ), where 224 kg ha -1 is the recommended N rate for tomato production in Florida. Soluble urea was split applied weekly over the 13-week growing season, whereas CRUs were applied at the full rate once at preplant. For all seasons, biweekly SPAD meter readings were taken and sampling periods coincided with the vegetative, flowering, fruit set, fruit growth, and harvest growth stages. Overall, minimal differences in tomato N status were observed among the tested N rates and N sources, indicating that all N fertilizer practices tested maintained similar N use. Thus, irrespective of the N source, this study found that tomato N demands could be met at a 38% reduction of the recommended N rate, potentially enhancing NUE in tomato production systems cultivated on sandy soils in north Florida.
Speakers
LJ

Laura Jalpa

University of Florida
Co-authors
RM

Rao Mylavarapu

University of Florida
NA
Tuesday September 24, 2024 11:00am - 11:15am HST
Kahili

11:00am HST

POM 1 - Carbohydrate And Nitrogen Storage Are Inversely Affected By Crop Load For 'Honeycrisp' And 'Gala' Apples
Tuesday September 24, 2024 11:00am - 11:15am HST
Biennial or alternate bearing is characterized by an abundance of blooming and fruiting in “on” years and a lack of blooming and fruiting in “off” years. Biennial bearing in fruit tree production has been extensively studied. However, it continues to be problematic in certain crops and cultivars. Fundamental physiological mechanisms controlling this behavior are still poorly understood. Along with carbohydrates in plant tissues, reserve nitrogen influences early-season growth in apples, with the percent contribution of reserve nitrogen being dependent on the current nitrogen supply. Because flowering and fruit set occur in spring alongside bud break, reserve nitrogen can significantly affect these processes too. We sought to understand the role carbohydrate and nitrogen storage in various plant tissues has on biennial bearing for ‘Honeycrisp’ apple. Apical buds, terminal shoots, and one-year-old spurs were collected in 2022
Speakers
TC

Thiago Campbell

Washington State University
Co-authors
LK

Lee Kalcsits

Washington State University
NA
Tuesday September 24, 2024 11:00am - 11:15am HST
Nautilus 1

11:00am HST

TCHG 1/ADMIN - Evaluation of Packback - an AI-Assisted Writing Program for Student Assignments in Horticulture Courses
Tuesday September 24, 2024 11:00am - 11:15am HST
The use of Artificial Intelligence (AI)-supported writing tools in higher education has been a hot topic since OpenAI introduced ChatGPT in 2022. These AI-supported writing tools are intended to analyze written materials and provide feedback on the writing , including grammar, vocabulary, content, and structure. Packback (https://www.packback.co/) is one of the AI-supported online platforms that intends to improve student curiosity, communication skills, and critical thinking, and provides ease of assessment for instructors. Two instructors in the Department of Horticultural Sciences at Texas A
Speakers Co-authors
Tuesday September 24, 2024 11:00am - 11:15am HST
South Pacific 4

11:00am HST

WCPM 1 - Tolerance of Peppermint to Herbicides Applied Post-Harvest
Tuesday September 24, 2024 11:00am - 11:15am HST
After harvest, peppermint is vulnerable to weed interference due to the loss of crop canopy. However, few herbicides are registered for use during this critical time in the production cycle. In response to this, we conducted research trials in 2023 at two commercial peppermint production fields in Indiana (North Judson and Fair Oaks) to determine peppermint response to preemergence and postemergence herbicides. Preemergence herbicide treatments included Zidua (1.84 fl oz/a), Optogen (3 fl oz/a), Spartan (4 fl oz/a), Chateau EZ (4 fl oz/a), Dual Magnum (1 pt/a), Fierce EZ (10 fl oz/a), and Tenacity (3 fl oz/a). Postemergence herbicide treatments included Basagran (2 pt/a), Reviton (2 fl oz/a), Tough (24 fl oz/a), Sharpen (2 fl oz/a), Anthem Flex (4.5 fl oz/a), Aim (1 fl oz/a), and Tough (24 fl oz/a) plus either Optogen (1.5 fl oz/a), Tenacity (1.5 fl oz/a), or Basagran (2 pt/a). Visible crop injury on a scale of 0 (no injury) to 100% (crop death), as well as crop height, was recorded every other week after treatment. Eight weeks after treatment, the greatest injury was observed was from the Group 14 herbicides: Reviton (81-84%), Sharpen (81-88%), and Aim (33-54%). Injury from Group 27 herbicides, Optogen and Tenacity, was more severe at Fair Oaks (63% and 64%, respectively) than at North Judson (28% and 12%, respectively). However, combining a half rate of these herbicides with Tough greatly increased crop injury at both locations (>73%). Injury from Chateau EZ and Fierce EZ differed by location; injury was lower at North Judson (13% and 7%, respectively) than at Fair Oaks (42% and 55%, respectively). Crop injury from Zidua, Dual Magnum, Spartan, Basagran, and Tough plus Basagran were similar to, or less than, Tough applied alone (the registered grower standard). Peppermint height and end-of-season aboveground biomass followed similar trends.
Speakers
SM

Stephen Meyers

Purdue University
Co-authors
CL

Carlos Lopez Manzano

Purdue University
NA
CC

Celia Corado Mendoza

Purdue University
NA
EC

Emmanuel Cooper

Purdue University
NA
JA

Jeanine Arana

Purdue University
JC

Josue Cerritos

Purdue University
NA
Tuesday September 24, 2024 11:00am - 11:15am HST
Lehua Suite

11:00am HST

Division VP and Interest Group Officer Meeting
Tuesday September 24, 2024 11:00am - 12:00pm HST
Division VP and Interest Group Officers Meeting to discuss updates on division ASHS business.
Speakers
LL

Leonardo Lombardini

ASHS International Division VP
JC

Javier Castillon

ASHS Industry Division VP
BS

Becky Sideman

Member-At-Large
avatar for Sarah White

Sarah White

Research Division VP
Sarah's research involves using plants to clean water. She is passionate about mentoring young faculty and graduate students to help them succeed in the future.
CR

Carolyn Robinson

Education Division VP
Tuesday September 24, 2024 11:00am - 12:00pm HST
Coral 4

11:15am HST

CE 1 - Supplemental Blue and UV-B Light Enhances Amino Acid-Derived Flavor Compounds in Greenhouse-Grown Tomatoes
Tuesday September 24, 2024 11:15am - 11:30am HST
Tomato production under controlled environmental conditions presents challenges due to the selective permeation of solar radiation within enclosed structures or the limited wavelengths produced by artificial light sources. Despite these challenges, growers increasingly opt for such production systems due to the enhanced uniformity and yield of fruit compared to open-field cultivation. However, controlled environment conditions, particularly greenhouses, often limit specific wavelengths of light, including blue and UV-B radiation. This limitation has the potential to alter flavor and overall fruit quality. Therefore, the present investigation examined how supplemental blue and UV-B light, independently and in combination, influence the levels of amino acid–derived flavor compounds, particularly those derived from branched-chain and aromatic amino acids, in two tomato varieties, Plum Regal (PR, commercial) and TAM HOT-Ty (THT, Texas A
Speakers
SB

Samikshya Bhattarai

Graduate Research Assistant, Texas A&M University
Co-authors
Tuesday September 24, 2024 11:15am - 11:30am HST
Coral 1

11:15am HST

CHEX 1 - Kenaf (Hibiscus cannabinus) Compost As An Alternative To Peat
Tuesday September 24, 2024 11:15am - 11:30am HST
Global growing media demand is projected to increase 400% by 2050. Growers are interested in alternative substrates due to the restrictions placed on peat harvesting, as well as transportation and supply chain issues associated with peat. Kenaf (Hibiscus cannabinus), a tropical fibrous plant that was grown and composted in Florida, was evaluated to determine its potential as a horticultural substrate. Research trials were conducted in South Florida to determine effectiveness of kenaf as an alternative substrate for seed germination and plant establishment when compared to a commercially available compost and commonly used growing media. Seed germination trials consisted of planting arugula (Erica sativa) in seed trays filled with either (1) kenaf compost [KC], (2) commercially available compost [CC], or (3) ProMix HP [PM]. Germination was monitored daily, and mean emergence was determined. To evaluate plant establishment, a container trial was conducted using Lantana (Lantana camara) plants that were originally planted in Metro-Mix and transplanted from 1-gallon to 3-gallon plastic containers filled with either KC, CC or PM. Plant visual quality, percent wilt and volumetric water content(VWC) were evaluated weekly and root biomass was determined when plants were deconstructed at the end of the three-month trial. Results show that there were no treatment differences for percent seed emergence of arugula, with all emergence reaching over 80%. Plant establishment in the first field trial found KC and CC treatments increased VWC when compared to PM. Higher visual quality ratings of plants in KC and CC substrates may be explained by the increase in VWC. Lantana plants transplanted and grown in KC were uniform and grew equally as well as CC and better than PM on 13 of 14 rating dates. These data show there is no difference in arugula seed emergence when planted in CC, PM or KC. Lantana establishment in KC was comparable in CC and better than in PM growing media.
Speakers
SS

Shawn Steed

University of Florida
Co-authors
AW

AC Wilkie

University of Florida
NA
CA

Conner Austin

University of Florida
DC

DG Clarik

University of Florida
NA
EB

E Babaeian

University of Florida
NA
GL

G Landry- Maltais

University of Florida
NA
LF

Liz Felter

University of Florida
NA
MM

mica mcmillan

University of Florida
NF

N Franklin

University of Florida
NA
Tuesday September 24, 2024 11:15am - 11:30am HST
South Pacific 2

11:15am HST

MKEC - Consumer Preferences for Commercially Available Poinsettia Cultivars in South Mississippi
Tuesday September 24, 2024 11:15am - 11:30am HST
Mississippi State University’s South Mississippi Branch Experiment Station began hosting a Poinsettia Open House in 2021. The goal of this event was to provide retail consumers and commercial producers with up-to-date information about poinsettias currently available for production. The first two events were single day events in early December (December 2, 2021 and December 1, 2022). Due to the success of the first two events, a decision was made to expand the event to two days in 2023 (December 1-2, 2023) and include educational presentations. Photography backdrops with poinsettia enhancements have been provided each year for anyone wishing to use them for Christmas card photos or to simply commemorate their visit. Attendees were given the opportunity to participate in several surveys at each open house. Participants completing a survey were allowed to choose and take home a poinsettia. Attendees were allowed to walk through the production greenhouse, view the poinsettia cultivars, and record their personal favorites. Participants viewed 35, 52, and 40 poinsettia cultivars in 2021, 2022, and 2023, respectively. In 2021, attendees identified Ice Punch, Orange Glow, Premium Ice Crystal, Superba New Glitter, and Autumn Leaves as their top five favorites. In 2022, attendees identified Superba New Glitter, Ice Punch, Norwin Orange, Prestige Maroon, and Grande Italia as their top five. In 2023, attendees identified J’Adore Soft Pink, Premium Picasso, Christmas Feelings Merlot, Christmas Spirit, and Tapestry as their top five.
Speakers
PK

Patricia Knight

Mississippi State University
Co-authors
AB

Anthony Bowden

University of Arkansas
BP

Ben Posadas

Mississippi State University
NA
CC

Christine Coker

Mississippi State University
NA
HW

Haley Williams

Mississippi State University
JD

James DelPrince

Mississippi State University
NA
JR

Jenny Ryals

Mississippi State University
SL

Scott Langlois

Mississippi State University
Tuesday September 24, 2024 11:15am - 11:30am HST
South Pacific 1

11:15am HST

NUR 1 - Effects of Water Quality and Fertilization Practices on Container Tree Growth in Nurseries
Tuesday September 24, 2024 11:15am - 11:30am HST
The Covid-19 pandemic and ensuing lockdowns led to an increase in revenue and production for green industry products in early 2020. In Study 1. an evaluation of fertigation (liquid feed, quick release) and controlled release fertilizers (CRFs, slow release) were applied to container-grown (7 gallon) live oak (Quercus virginiana) and Nutall oak (Quercus nuttallii) trees (100% Liquid feed, 0% CRF, 67% Liquid feed, 33% CRF, 33% Liquid feed, 67% CRF, 100% Liquid feed, 0% CRF). Live oak trees fertilized with CRFs had increased stem calipers (>30%). Nuttall stem caliper and height were significantly increased by 62% and 58%, respectively, with substrate incorporation of CRFs. Live oak tree height was increased by 35% and stem caliper when CRFs were incorporated. In study 2, the effect of alkaline water quality on live oak tree production was initiated at a nursery in Point Coupee Parish. Ca and Mg sources were used to study the impact of water quality on live oak tree container-growth and study the benefits of using different rates of lime and gypsum [0% dolomitic lime (Ca, Mg), 100% gypsum (Ca) Epsom salt (Mg), 25% dolomitic lime (Ca, Mg), 75% gypsum (Ca) Epsom salt (Mg), 50% dolomitic lime (Ca, Mg), 50% gypsum (Ca) Epsom salt (Mg), 75% dolomitic lime (Ca, Mg), 25% gypsum (Ca) Epsom salt (Mg), 100% dolomitic lime (Ca, Mg) 0% dolomitic lime]. Live oak tree growth measurements increased with the reduction of dolomitic lime and increase of Epsom salt and gypsum applications. Leaf Na content was significantly reduced using higher proportions of gypsum and Epsom salt. Soil pH was also reduced by more than 1 pH unit after a growing season. Soil pH did increase when irrigated with highly alkaline water. Growers using alkaline water need to manage irrigation water and soil pH and consider using gypsum and Epsom salt reducing dolomitic lime rates as a source of Ca and Mg. All Ca and Mg sources provided greater than the threshold levels of leaf Ca and Mg content.
Speakers
ZD

Zachary Davis

LSU AgCenter
Co-authors
EB

Edward Bush

LSU AgCenter
Tuesday September 24, 2024 11:15am - 11:30am HST
South Pacific 3

11:15am HST

PNM 1 - Understanding Nitrogen Uptake Potential of Two Wetland Plants Under Varied Water Temperatures and Nitrogen Concentrations
Tuesday September 24, 2024 11:15am - 11:30am HST
Excessive use of commercial fertilizers in nursery production results in substantial fertilizer runoff, leading to surface and groundwater contamination. Therefore, to prevent contamination and comply with regulations, irrigation return flow (runoff water) is generally collected in a retention pond before it can be safely discarded or released. Nitrogen, applied as nitrate compounds is among the highest used fertilizer and is prone to leaching and runoff. Employing a phytoremediation strategy to remediate irrigation return flow (runoff water) has the potential to lower nitrate concentrations in water before release. In this study, we assessed the suitability of growing Helianthus maximiliani (maximilian sunflower) and Asclepias speciosa (showy milkweed) in a floating treatment wetland system (FTW) and evaluated the nitrate uptake capacity of these plants grown in three different nitrogen concentrations i.e., 10, 20, and 30 mg/L and two water temperatures of 75°F and 85°F. Increasing water temperature increased growth index for both species and increased dry weight for Asclepias speciosa. However, for Helianthus maximiliani, increasing temperature had a lesser effect on total dry weight. The accumulation of nitrate nitrogen in plant tissue was higher in Helianthus maximiliani at the nitrate nitrogen concentration of 20 mg/L under both temperature treatments. However, in Asclepias speciosa, the accumulation of nitrate nitrogen in plant tissue was higher at the high temperature treatment of 85⁰F and 20 mg/L nitrate nitrogen concentration. The nitrate nitrogen uptake from both plants in this study indicated suggests that Helianthus maximiliani ‘maximilian sunflower’ and Asclepias speciosa ‘showy milkweed’ can be grown as FTW and be used to remove nitrogen from a nursery retention pond.
Speakers
SB

Saroj Burlakoti

Utah State University
Co-authors
SP

Shital Poudyal

Utah State University
NA
Tuesday September 24, 2024 11:15am - 11:30am HST
Kahili

11:15am HST

POM 1 - Striking the Right Balance: Innovative PGR Strategies for Fruit Drop Mitigation and Color Enhancement in Apples
Tuesday September 24, 2024 11:15am - 11:30am HST
In apple orchards, addressing pre-harvest fruit drop in early-maturing, commercially valuable cultivars like ‘Honeycrisp’ and ‘Gala’ is crucial. This issue is largely linked to ethylene, a ripening hormone that, despite its role in enhancing fruit qualities, triggers premature fruit drop. From 2018 to 2021, extensive field trials were conducted across commercial and experimental orchards to refine the application of two ethylene-inhibiting products, ReTain (AVG-15%) and Harvista (1-MCP-1.3%), in mitigating this challenge in ‘Gala’ apples. Our findings confirmed AVG’s effectiveness in reducing fruit drop and stem-end splitting; however, AVG application consistently resulted in diminished fruit coloration. In the subsequent seasons of 2023 and 2024, our research pivoted towards identifying plant growth regulator (PGR) formulations that could balance the dual objectives of minimizing fruit drop and preserving color development in ‘Honeycrisp’ and ‘Gala’ apples. Key findings include: a) the multiple applications of Accede (ACC-10%) and Motivate (Ethephon-21.7%) starting from three weeks before harvest significantly enhanced red color formation in ‘Honeycrisp’ and ‘Gala’ apples, surpassing control and ReTain treatments, though Motivate increased the rate of fruit drop; b) ReTain, both alone and in combination with Accede, notably reduced fruit drop, with the ReTain-Accede mix also enhancing fruit coloration; c) combining ReTain and Motivate neither decreased fruit drop nor enhanced color; d) the positive impact of the ReTain-Accede mix on color was biochemically and molecularly validated; e) Accede's color-enhancing effect appears to be ethylene-independent. This research underscores the potential of specific PGR mixes in achieving a harmonious balance between reducing fruit drop and enhancing fruit coloration.
Speakers
avatar for Sherif M. Sherif

Sherif M. Sherif

Associate Professor, Virginia Tech
Dr. Sherif M. Sherif is an Associate Professor at Virginia Tech, where he channels his fervent zeal for life sciences and educational outreach into his specialization in tree fruit physiology and molecular biology. His career is defined by a dedication to overcoming the biological... Read More →
Co-authors
KJ

Khalil Jahed

Virginia Tech
NA
MT

Mohammad Tipu

Virginia Tech
NA
Tuesday September 24, 2024 11:15am - 11:30am HST
Nautilus 1

11:15am HST

TCHG 1/ADMIN - Evolution Of An Undergraduate Tropical Crop Production Systems Course
Tuesday September 24, 2024 11:15am - 11:30am HST
TPSS 300 Tropical Production Systems is a four-credit undergraduate crop production course. It has two lectures and one lab period a week. In Spring 2023, there were 16 undergraduate students registered for this every Spring offered course—12 TAE students, one NREM student, one Interdisciplinary Studies student, one Botany student, and one Hawaiian student. In Spring 2024, there were nine undergraduate students—six TAE students, one Botany student, one Journalism student, and one Elementary Education & Special Education student. The objective is to describe the improvements made to TPSS 300 based on student interests and emerging new technologies and disciplines in horticulture. Various teaching techniques were used including flipped classroom, small group discussions, class discussions, in-class activities, lectures, guest speakers, field trips, YouTube videos, and laboratories. With a BYOD format, students could review assigned materials and look up information on the Internet to aid group discussions. New topics were added such as agricultural drone technology and crop sensors and equipment for monitoring plant status. Besides inviting our department graduate students as guest speakers, department extension agents and faculty and faculty and graduate students from other departments were invited. A TPSS faculty with another department’s faculty discussed the regulations for drone use and gave a demonstration of flying drones. The TPSS graduate students spoke on breadfruit tissue culture and industrial production in Hawaii; innovative agroforestry in ancient ways; and taro in aquaponics. Extension agents spoke about food safety. A PEPS graduate student spoke on invasive pests impacts on palm species with a focus on the Pacific and Israel. Two GEO students demonstrated their experimental growth chambers and artificial lighting set up. The manager of our college’s greenhouse facilities provided a tour of the facilities, explaining maintenance and irrigation. The rigor of this course was increased through incorporating more mathematics and quantitative reasoning, growth analysis, yield analysis, crop modeling and simulation, computer applications in horticulture, and high technology in horticulture. Students commented that TPSS 300 was a valuable learning experience. The course provided diverse learning experiences and hands-on activities. The integration of graduate students, extension agents, and the greenhouse manager as guest lecturers into the course worked well, providing benefits to both the speakers and the students.
Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
Tuesday September 24, 2024 11:15am - 11:30am HST
South Pacific 4

11:15am HST

WCPM 1 - Developing a Biobased, Compostable Mulch that Crops Grow Through
Tuesday September 24, 2024 11:15am - 11:30am HST
Plastic mulch films and geotextile landscape fabrics are not compatible with specialty crops grown at high densities with narrow in-row spacing. As a result, many growers resort to hand weeding these specialty crops, including leafy greens, carrots, and matted-row strawberries. Our objective was to develop and test value-added weed barrier mulches designed specifically for these crops to grow on and root through. We have conducted 13 trials across 3 crops (lettuce, carrot, and strawberry) and 3 years to evaluate 9 different biobased, compostable weed barrier mulches (BCMs) that include polylactic acid (PLA) resin. The BCMs tested varied in weight basis and material composition including: 1) PLA-only (80, 120, and 180 g/m2), 2) PLA embedded organic fertilizers (soybean meal and composted turkey litter; 150 and 210 g/m2), and 3) PLA paper (105 and 210 g/m2). The BCMs are installed in the field like a typical mulch film roll but are then covered with a 1 to 2.5 cm layer of compost (or other weed-free media) and crop seeds. Data was collected to evaluate effects of BCMs on weed density, soil nitrogen availability, moisture, and temperature, microbial abundance, and crop establishment, yield, and quality. Across all crops and site-years, BCMs reduced weed emergence by 80% to 97% compared to bare soil, and weed suppression was best in PLA paper. The BCMs immobilized some available soil nitrogen and embedded fertilizers in the BCM did not affect this outcome. In carrot, BCMs increased mycorrhizal fungi abundance by up to 59% compared to bare soil. In strawberry, BCMs increased crop canopy area by up to 51%. Yields were usually not different between BCMs and bare soil because weeds were removed weekly after counting. However, poor seedling establishment on BCMs due to heavy rainfall after planting in 2022 reduced carrot yield by 13% and lettuce yield by 20%. To address this issue, lettuce in 2023 was planted in two shallow seed furrows filled with compost on the BCM (instead of broadcast planting across the entire BCM bed top as in previous years). Lettuce establishment in the furrows was two times greater than in bare soil due to improved tilth and reduced erosion, and yield was not different from bare soil. Volumetric soil moisture in BCM compost seed furrows was 27.1% compared to 35.7% in bare soil, highlighting differences in texture and the importance of irrigation in the BCM system during establishment.
Speakers
SW

Samuel Wortman

University of Nebraska - Lincoln
Co-authors
CW

Caleb Wehrbein

University of Nebraska - Lincoln
CP

Chris Proctor

University of Nebraska - Lincoln
NA
CR

Claudio Rojas

University of Costa Rica
NA
EJ

Elizabeth Jeske

University of Nebraska - Lincoln
NA
IK

Ignatius Kadoma

3M Company
NA
LD

Lisa Durso

USDA ARS
NA
MU

Manuel Umana

University of Costa Rica
NA
ML

Mia Luong

University of Nebraska-Lincoln
NA
RD

Rhae Drijber

University of Nebraska - Lincoln
NA
Tuesday September 24, 2024 11:15am - 11:30am HST
Lehua Suite

11:20am HST

Exhibitor Talk: PP Systems
Tuesday September 24, 2024 11:20am - 11:35am HST
Tuesday September 24, 2024 11:20am - 11:35am HST
Coral 5

11:30am HST

CE 1 - Characterizing the effect of blue light on water relations of unrooted cuttings during indoor acclimation
Tuesday September 24, 2024 11:30am - 11:45am HST
Managing water loss of unrooted cuttings (URC) during acclimation is critical to decrease crop losses and shorten rooting time. Vertical indoor propagation (VIP) systems that use indoor-farming technologies enable the opportunity to optimize the environment for URC acclimation. However, recommend environmental setpoints for VIP systems are unknown. Light quality affects various morphological and physiological processes in plants, and blue light in particular, has an effect on stomatal opening and plant size, both of which regulate water relations of plants. Therefore, the objective of this study was to characterize short-term effects of increasing percentages of blue light on water relations of Chrysanthemum ‘Crystal Bright’ and Begonia ‘Dark Britt’ URC. Four light-quality treatments were evaluated: 15%, 30%, 45%, or 60% blue light. All treatments provided a photosynthetic photon flux density of 70 µmol·m–2·s–1 delivered by broadband and monochromatic-blue light-emitting diode fixtures. Ambient temperature, relative humidity, and carbon dioxide concentration were set at 22 °C, 70%, and 420 μmol·mol–1. Water uptake and water loss were evaluated by placing individual URC in vials with and without water, and exposing them to each treatment for 24 or 48 h, respectively. Changes in water loss were also recorded at various intervals for 24 h. Water uptake of Chrysanthemum linearly increased as blue-light percentages increased. In contrast, water uptake followed a quadratic response for Begonia, which peaked at 45% blue light. Water loss also followed a quadratic response for begonia, with increasing values up to 30% blue light. Water loss of Chrysanthemum followed linear response to increasing blue light. After 24 h, water loss of Chrysanthemum linearly increased with increasing blue light, from 0.65 to 0.76 g under 15% and 60% blue light, respectivey. There were no treatment differences for stomatal conductance, but leaf vapor pressure deficit linearly increased with increasing blue light, regardless of species. These findings show that blue light affects water relations of URC, which should be considered when making lighting recommendations for VIP systems.
Speakers
AS

Ana Sofia Gomez

Purdue University
Co-authors
CG

Celina Gomez

Purdue University
Tuesday September 24, 2024 11:30am - 11:45am HST
Coral 1

11:30am HST

MKEC - Understanding the Characteristics of Ethnic Markets and Help Small Growers to Find Niche
Tuesday September 24, 2024 11:30am - 11:45am HST
Many small and socially disadvantaged producers grow fruit and vegetables. These farmers start small to satisfy family needs and support a preferred lifestyle. However, many small and socially disadvantaged farmers aim to be economically sustainable and want to create a feasible operation rooted in their communities. Since 2016, we have gathered information from over 3,000 small and socially disadvantaged farmers in the Southeastern region of the US who seek opportunities to improve wealth and health for individuals and communities. Information includes types of operations, family compositions, and needs of training and assistance. In particular, many of these farmers went through a series of experiential training programs to grow medicinal crops originated in Asia. These specialty fruit and vegetables are not familiar to most of the local farmers, and these specialty fruit and vegetables have high potential to serve as medicinal crops based on scientific studies. This presentation will introduce the components in this series of training linking production to market, financial assessment, risk evaluation, and niche opportunities to improve long-term health outcomes. The presentation will focus on connections and characteristics of ethnic markets, where most of these specialty fruit and vegetables are sold to diverse populations, from cultural and health perspectives. Market prices, consumer behaviors, and communication strategies will also be shared as examples to support small and socially disadvantaged farmers in breaking the barriers to access the ethnic market. Since 2016, this training program has assisted more than 1,000 producers to grow Asian medicinal crops, and successfully engaged in market activities serving diverse customers across the US.
Speakers
Tuesday September 24, 2024 11:30am - 11:45am HST
South Pacific 1

11:30am HST

PNM 1 - Combined Agronomic Biofortification of Iron and Zinc in Radish and Sunflower Microgreens
Tuesday September 24, 2024 11:30am - 11:45am HST
Iron (Fe) and Zinc (Zn) are two micronutrients which are crucial for human health and proper functioning of the circulatory, endocrine, immune, nervous, and reproductive systems. Deficiencies in dietary Fe and Zn can result in numerous illnesses and disorders and are among the most prevalent micronutrient deficiencies worldwide. There is an urgent need for improving the dietary intake of these micronutrients and a promising, quick, and effective improvement strategy is agronomic biofortification. Microgreens are an ideal and versatile choice for meeting nutritional needs. They are nutrient-dense, have low phytic acid content, can be produced for a range of species, and have a relatively short growth cycle – making them a convenient biofortification target crop. Previous studies’ attempts towards the simultaneous biofortification of Fe and Zn have indicated their antagonistic interactions during uptake, where the increase of one mineral led to a decreased uptake of the other. However, limited information is available about the opportunity of enriching microgreens with both nutrients using fertigation. Therefore, in this study we aimed to assess the optimal combination of Fe and Zn fertilizer concentrations, provided via fertigation, to maximize their simultaneous accumulation in radish and sunflower microgreens without impairing yield and quality. Using a completely randomized block design setup, a factorial combination of FeSO4 (0, 20, and 40 mg/L of Fe) and ZnSO4 (0, 10, and 20 mg/L of Zn) was tested. Across both species, it was observed that fertigation using the treatment combination of 40 mg/L FeSO4 and 20 mg/L ZnSO4, (Fe40-Zn20), resulted in a substantial increase of both micronutrient levels. Compared to the untreated control, the Fe40-Zn20 treatment increased Fe and Zn accumulation by about 200% and 900%, respectively, in radish microgreens, and about 180% and 600% in sunflower microgreens. Additionally, this treatment resulted in minimal yield reduction. Fresh and dry biomass decreased by approximately 23% and 9%, respectively, in radish microgreens, and 38% and less than 1% in sunflower microgreens. Although increasing both Fe and Zn content proves to be a challenging endeavor, this study revealed evidence of an optimal combination of selected Fe and Zn sources and application rates that, via fertigation, was effective in their simultaneous enrichment in two microgreen species.
Speakers
RR

Rishi Ravichandran

Student, Pennsylvania State University
Co-authors
EC

Erin Connolly

Pennsylvania State University
NA
FD

Francesco Di Gioia

Pennsylvania State University
PP

Pradip Poudel

The Penn State University
Tuesday September 24, 2024 11:30am - 11:45am HST
Kahili

11:30am HST

POM 1 - Impacts of Rootstock and Crop Load Adjustment on Fruit Quality and Mineral Nutrients in ‘Honeycrisp’ Apple
Tuesday September 24, 2024 11:30am - 11:45am HST
The influence of rootstock and time of crop load adjustment on ‘Honeycrisp’ apple fruit quality at harvest and after storage was studied over four seasons. Yield per trees varied from year to year because of biennial bearing. Trees on V.1 and G.30 were higher while those on G.969 often had lower yield per tree. Fruit from trees on M.26EMLA and G.30 were larger, while those on G.202 and G.969 were smaller than those on other rootstocks in two of three years. Fruit firmness at harvest and after storge was often inversely proportional to their size, so that fruits from trees on G. 202 often had higher but those on G.30 often had lower firmness at harvest and after storage. Percentages of fruit bitter pit among rootstocks at harvest was different than those after storage. However, fruit from trees on M.26EMLA, V.1, and G.30 generally had higher bitter pit than those on G.969 and G.202 rootstocks. Fruit fresh weight continually grew during growing season. However, the increase in percentage fruit dry weight reached a plateau on August 9, after which it leveled off. Trees receiving an “Early Heavy Thinning” and “Thinned Early to 1 Fruit/bunch” had lower yield but larger fruit with more bitter pit than Un-thinned-Control trees. Trees receiving a thinning on June 11 and June 25 had similar fruit size in the same season. However, bitter pit was increased, while fruit size decreased, as the hand thinning was delayed until July 8. Late hand thinning resulted in smaller fruit size with less bitter pit. Fruit potassium/ calcium (K/Ca) ratio did not change significantly between June 20 and August 8 within the same year. This research unveils importance of rootstock, time, and level of and thinning in the fruit quality of ‘Honeycrisp’ apple.
Speakers
EF

Esmaeil Fallahi

University of Idaho
Professor
Co-authors
BF

Bahar Fallahi

University of Idaho
NA
MK

Michael Kiester

University of Idaho
NA
Tuesday September 24, 2024 11:30am - 11:45am HST
Nautilus 1

11:30am HST

TCHG 1/ADMIN - Service-learning Horticulture Students Growing Food for Themselves and Others
Tuesday September 24, 2024 11:30am - 11:45am HST
Organic gardening (Horticulture 2525) is a mandatory class for students in the LSU medicinal plants and sustainable crop production concentrations, where the focus of the lab is for students to intensively grow their own garden plot of vegetables and herbs in the fall semester. Students are mandated to grow at least 10 different crops and to use both direct seeding and using their own transplants to establish, maintain throughout the semester, and then harvest their plot. The course is a service-learning course and over the years the class have worked in establishing and maintaining community and school gardens, harvesting/gleaning vegetables from garden plots, and assisting with a local farmers market. The most recent classes focused on growing food in community plots for the LSU Food Pantry, a local food bank that is used by many students. Each week students are required to work in the community rows from the beginning of working and shaping the beds, applying and incorporating fertilizer, planting seeds directly into the beds, transplanting crops, and setting up trickle and overhead irrigation systems. Students maintain their own plots as well as the community rows by fertilizing, and applying organic pest management measures as needed. The harvest from the individual plots and the produce is left up to the students and all the students harvest, wash, pack and prepare the product from the community rows for donation each week to the campus food pantry. Students are encouraged to participate my transporting the produce at least once, from the field or the cooler at the teaching facility to the food pantry. Many of the students have indicated that the class is the first time they had grown any plants in a garden and they used the garden harvest in their own kitchens. Students also indicated that they learned about the needs of the community and students and several also became aware of the food pantry and its services. In the fall of 2023 over 1,800 pounds of fresh vegetables were donated to the campus food pantry. Data from the students’ perceptions and comments from the semester will be presented.
Speakers
CM

Carl Motsenbocker

Professor, Executive Director Louisiana Farm to School Program, Louisiana State University
Dr. Carl Motsenbocker is a professor of horticulture and sustainable agriculture at Louisiana State University. Motsenbocker is Executive Director of the Louisiana Farm to School Program and teaches Organic Gardening, Sustainable Agriculture and Vegetable Crops at LSU. Motsenbocker... Read More →
Co-authors
IF

Isabella Frank

Louisiana State University
NA
JT

Jacob Tullos

Louisiana State University
NA
Tuesday September 24, 2024 11:30am - 11:45am HST
South Pacific 4

11:30am HST

WCPM 1 - Evaluating Application Approaches for Enhancing the Weed Suppression Effectiveness and Crop-Safety of Preemergence Herbi
Tuesday September 24, 2024 11:30am - 11:45am HST
Preemergence herbicide application under plastic mulch is an effective strategy for managing weeds in vegetable plasticulture production. However, applying herbicides under plastic mulch in raised beds carries the inherent risk of crop phytotoxicity. This underscores the importance of exploring crop-safe methods for herbicide application in beds covered with plastic mulch. The study aimed to evaluate the efficacy of preemergence herbicide S-metolachlor alone or in combination with super absorbent polymer, soil binding agent, or compost in effectively controlling weeds in plastic mulched tomato beds without impacting the crops. During trials, I and II, preemergence S-metolachlor was applied either as blanket sprays or in combination with super absorbent polymer, soil binding agent, and compost on raised beds before installing plastic mulch. Results from trial II showed that S-metolachlor soil binding agent and S-metolachlor compost mix suppressed weed density by over 85% and 68%, respectively. Similarly, treatments including S-metolachlor alone, S-metolachlor super absorbent polymer, S-metolachlor soil binding agent, and S-metolachlor compost led to a reduction in weed biomass by over 50% compared to the non-treated control. Importantly, these treatments did not significantly impact tomato crop vigor and chlorophyll content during trials I and II, nor did they affect tomato crop biomass and yield. In conclusion, utilizing preemergence S-metolachlor along with different application approaches tested shows promise for controlling tough weeds such as nutsedge in tomato plasticulture beds.
Speakers
RK

Ramdas Kanissery

University of Florida
Co-authors
RT

Ruby Tiwari

University of Florida
NA
Tuesday September 24, 2024 11:30am - 11:45am HST
Lehua Suite

11:30am HST

Navigating Waves of Professional Behaviors: Workshop 4
Tuesday September 24, 2024 11:30am - 12:30pm HST
In the section focused on professional behaviors, we'll delve into the often-overlooked yet critical nuances that can make or break a student or early career professional's transition into the professional realm. From mastering email etiquette to navigating the intricacies of multigenerational workplaces, we'll provide invaluable insights to help you navigate diverse professional settings with confidence. Understanding the expectations surrounding communication, both written and verbal, is essential, and we'll offer practical tips on crafting professional emails that leave a positive impression. Moreover, we'll explore the dynamics of multigenerational workplaces, where varying communication styles, work habits, and values converge. By fostering an understanding of these differences and learning effective strategies for collaboration and communication across generations, you will be better prepared to thrive in today's diverse and dynamic job market.
Speakers

Tuesday September 24, 2024 11:30am - 12:30pm HST
Coral 3

11:40am HST

Exhibitor Talk: LI-COR Biosciences
Tuesday September 24, 2024 11:40am - 11:55am HST
Tuesday September 24, 2024 11:40am - 11:55am HST
Coral 5

11:45am HST

CE 1 - Shedding Light on Nutrition: The Influence of Supplemental Lighting on Glucosinolate Concentrations in Brassica Plants and Their Potential Anticarcinogenic Effects in Human Diets
Tuesday September 24, 2024 11:45am - 12:00pm HST
Brassica plants contain important secondary metabolites, such as glucosinolates, and provide a nutritious addition to the human diet. Glucosinolates, when hydrolyzed, yield isothiocyanates which can affect the carcinogenesis process, and further research into increasing glucosinolate concentrations in plants is important for determining anticarcinogenic properties of brassicas in human diets. Kale (Brassica oleracea var. acephala cv. ‘Toscano’ ) and Arabidopsis (Arabidopsis thaliana, Col-0) were grown in the greenhouse under natural light (control) and subjected to three additional supplemental light treatments to determine the impact of supplemental LED lighting on glucosinolate concentrations. Treatments included no supplemental light (control), 75:25 Red:Blue LED, 50:50 Red:Blue LED, and Warm White LED light at 100 μmol.m-2.s-1 each. Plants were harvested when the first kale treatment group reached a leaf number of 7, and when half of all Arabidopsis flowers began opening. Harvested plants were analyzed for glucosinolate and mineral nutrient concentration. Statistical analysis on Arabidopsis data revealed significant differences among light treatments in glucosinolate concentrations, particularly glucoraphanin and gluconasturtiin. Additionally, significant differences were found in leaf and petiole mass and leaf number of both kale and Arabidopsis at harvest. The no supplemental light control produced the lowest harvest mass compared to plants receiving supplemental light. Preliminary qPCR analysis of Arabidopsis displays variations in the relative expression of genes CYP79B2 and CYP83A1, varying across treatment when compared to the control. Glucosinolate analysis of kale resulted in no statistically significant differences among all four light treatments. However, glucosinolates, including gluconapin, glucoraphanin, gluconasturtiin, and several unknowns, were found to be present across all four treatments. As glucosinolates are stress-response compounds, their lack of variation in kale and significant variation in Arabidopsis under different light environments indicate that other environmental factors also play a crucial role in their production. Further research is necessary to identify abiotic and biotic factors influencing their concentration in the greenhouse environment for both species.
Speakers
SB

Skyler Brazel

University of Tennessee - Knoxville
Co-authors
CZ

Caleb Zepeda

University of Tennessee - Knoxville
NA
CS

Carl Sams

University of Tennessee
SN

Samantha Nuzzi

Donald Danforth Plant Science Center
NA
TB

Tessa Burch-Smith

Donald Danforth Plant Science Center
NA
Tuesday September 24, 2024 11:45am - 12:00pm HST
Coral 1

11:45am HST

MKEC - Consumers' WTP on Sustainability Turfgrass Attributes with Consideration of Aesthetic Attributes and Water Conservation Policies
Tuesday September 24, 2024 11:45am - 12:00pm HST
This study estimates consumers’ willingness to pay (WTP) for sustainability turfgrass attributes such as low-input and stress-tolerance attributes, while considering potential trade-off relationships between aesthetic attributes and sustainability attributes. To address our objectives, our study conducts a choice experiment and estimates two mixed logit models. The first model includes low-input, winter kill, and shade-tolerance attributes as predictor variables, and the second model extends the first model by adding interaction terms between aesthetic and sustainability attributes. Another choice experiment is conducted under water policies with various water rate increase and watering restriction scenarios. Results from the mixed logit models show that overall, higher low-input cost reduction, less winter-damaged, and more shade-tolerance grasses are preferred, the direct effect of aesthetic attributes on consumers’ preference is strong, but the indirect effect represented by the interaction terms are generally statistically insignificant. Our results indicate that consumers like to have a pretty lawn, but no strong consideration is given to the aesthetics of their lawn when selecting low-input and stress-tolerance turfgrasses. Our choice experiment under water policy scenarios suggests that water pricing is more effective than watering restriction in increasing consumer demand for water-conserving turfgrasses. Our findings provide useful implications for future research in turfgrass breeding and evaluation of consumer preference for turfgrass. Many researchers have discussed potential degradation of aesthetic characteristics when developing input-saving turfgrass varieties. However, to the best of our knowledge, no earlier studies have investigated the effect of aesthetic deterioration caused by enhanced low-input and stress-tolerance attributed on consumers’ valuation of turfgrasses. Our findings suggest that aesthetic attributes need to be considered when conducting choice experiments for the valuation of the enhanced grasses, but limiting trade-offs may not be as important as enhancing low-input/stress-tolerance attributes when developing future turfgrasses. Another contribution might be the water policy outcomes from our choice experiment. Our experiment finds that the water pricing is more effective than the watering restriction in increasing consumer demand for water-conserving grasses, which could help develop better water policies in the future.
Speakers
CC

Chanjin Chung

Oklahoma State University
Co-authors
HJ

Hyojae Jung

Oklahoma State University
NA
Tuesday September 24, 2024 11:45am - 12:00pm HST
South Pacific 1

11:45am HST

POM 1 - Rapid Fruit Growth Rates of Honeycrisp Apples Cause Premature Dysfunction of Xylem, Reduced Peel Calcium, and Increased Susceptibility to Bitter Pit
Tuesday September 24, 2024 11:45am - 12:00pm HST
Insufficient transport of calcium to and throughout the cortex of apple is a primary factor contributing to bitter pit, a disorder characterized by dark lesions on the fruit surface. Calcium transport, in-planta, occurs solely in the xylem. Progressive transport dysfunction of xylem limits calcium concentration in the peel and subtending tissue. Rapid fruit growth may accelerate xylem dysfunction due to the stretching, shearing, or compressing of xylem elements. The relative time course of these events and subsequent effect on calcium concentration of peel tissues is not well understood. Growth rate of fruit was manipulated by manually adjusting the crop load of 6th leaf ‘Honeycrisp' trees to either 4 (low), 8 (moderate), or 16 (high) fruit per cm2 of trunk cross-sectional area via bud extinction. Fruit mass, xylem functionality, and peel calcium content were assessed weekly throughout the season. Fruit tissues were frozen weekly to evaluate the expression of genes related to xylogenesis and calcium transport and for quantification of hormones. At maturity, 25 trees were harvested from each crop load treatment. Fruit were assessed for bitter pit, stored for three months in regular air (3⁰C), then reassessed. Crop load influenced both xylem functionality and bitter pit incidence of fruit. Low crop load fruit lost 80% of xylem functionality by 8 weeks after bloom, which was two weeks earlier than moderate crop. By seven and five weeks before harvest, total xylem dysfunction was observed in fruit of low and moderate crop load, respectively; xylem in high crop load fruit never became fully dysfunctional. Final fruit mass from low crop load trees was only 20 grams larger than fruit from moderate crop load trees, yet, these fruit had a roughly 100% increase in bitter pit incidence at harvest (27.3% vs. 12.6%). Only 4.1% of high crop load fruit were affected by bitter pit. Many previous studies have ascribed the positive relationship between fruit mass and bitter pit incidence to calcium dilution. Our data suggest, however, that the issue is one of transport limits that appear to begin very early in fruit development, exacerbated by the growth rate of fruit, resulting in less peel calcium and higher bitter pit incidence at harvest than fruit of relatively lower growth rates. Future analysis of endogenous hormone concentrations and expression of genes relating to xylogenesis and calcium allocation will facilitate a better understanding of the processes governing xylem dysfunction and its association to bitter pit disorder.
Speakers
CG

Chayce Griffith

Michigan State University
Co-authors
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
TE

Todd Einhorn

Michigan State University
NA
Tuesday September 24, 2024 11:45am - 12:00pm HST
Nautilus 1

11:45am HST

TCHG 1/ADMIN - Hands-on Horticulture Activities for Undergraduate Introduction to Horticulture Courses
Tuesday September 24, 2024 11:45am - 12:00pm HST
Two intended learning outcomes of our undergraduate introduction to horticulture courses are for students to be more aware of the horticultural plants and practices that they encounter in their daily lives and to enthusiastically engage in growing and caring for plants. While lectures provide students with a framework on which to hang their expanding knowledge of plant science and horticultural concepts, we have found that including hands-on activities that allow students to reconstruct their own knowledge framework and connect the concepts to their daily lives has successfully engaged students and improved achievement of learning outcomes. In this presentation, we will describe how we have integrated a new introductory horticulture textbook, lectures, and hands-on ‘Seeing Horticulture’ activities, and examine student learning outcomes, in courses at Montana State University, the University of Minnesota, and the University of Wisconsin-Madison.
Speakers
CL

Claire Luby

Montana State University
Co-authors
TM

Tom Michaels

University of Minnesota
NA
Tuesday September 24, 2024 11:45am - 12:00pm HST
South Pacific 4

11:59am HST

Genetics and Germplasm 1 (GG 1)
Tuesday September 24, 2024 11:59am - 1:10pm HST
Chromosome Level Assemblies of Phoenix dactylifera L. 'Medjool' and 'Deglet Noor' - Yoko Hiraoka
Development of Haplotype-Phased, Chromosome-scale Genomes for Pomegranate - Alexander Schaller
In Planta Transformation Efficiency Assessment of Different Agrobacterium Strains and Explant Types in Catharanthus rose - Ting Hsuan Huang
Native Southern Red Aroniaberry (Aronia arbutifolia) Response to Chill Hours in Georgia - Leynar Leyton
Enhancing Ornamental Traits through Induced Polyploidy in Hibiscus hamabo: A Cytomolecular Analysis - Hamidou Sakhanokho
Insights into the Genetic Diversity and Population Structure of Wild and Cultivated Spinach - Gehendra Bhattarai
Population Analysis of Wild-type Venezuelan Sabadilla - Luke Czerwinski

Moderator
Tuesday September 24, 2024 11:59am - 1:10pm HST
South Pacific 2

11:59am HST

Ornamentals/Landscape and Turf 1 (O/LT 1)
Tuesday September 24, 2024 11:59am - 1:20pm HST
Evaluation of Native Azaleas for Container Production in the Mid-Atlantic - William Errickson
Facilitating Pollinator Conservation in Agriculture: Understanding Grower Needs in Obtaining IPM Certification - Madison Love
Relationship between Soil Water Content, Quantum Efficiency, Stomatal Conductance and Stem Water Potential in Salvia guaranitica ‘Black and Blue’ - Lindsey Trinkle
Effect of Coconut Coir and Biochar Media on Ornamental Plant Growth and Nutrient Leaching - Saroj Burlakoti
Physiological and Morphological Characteristics of Marigold Exposed to Different Ratios of Blue Light and Red Light - Anju Chaudhary
Responses of Three Ornamental Species to Saline Water Irrigation - Zirui Wang
Field Performance of Penstemon Species under Deficit Irrigation - Zirui Wang
Responses of Calamagrostis ×acutiflora under Deficit Irrigation - Zirui Wang
Moderator
avatar for Madison Love

Madison Love

North Carolina State University
My research is uniquely focused on conserving natural resources and fostering environmental stewardship. This is achieved through actively engaging communities in pollinator conservation efforts, supporting growers in adopting integrated pest management (IPM) along with creating pollinator... Read More →
Tuesday September 24, 2024 11:59am - 1:20pm HST
Kahili

11:59am HST

Weed Control and Pest Management 1/Hemp Research and Extension (WCPM 1/HEMP)
Tuesday September 24, 2024 11:59am - 1:50pm HST
Evaluating Efficacy of Organic Herbicides on Common Weed Species - Carly Strauser
Evaluating Fall Cover Crops for Enhanced Soil Properties and No-Till Weed Suppression in Chickpea Production in Virginia - Zelalem Mersha
Impact of Cover Crops and Herbicides on Early Season Weed Control and Sweetpotato Storage Root Yield. - Richard Noel Torres
Effects of Row-middle Cover Crops on Strawberry Plasticulture Production - Jeanine Arana
Palmer Amaranth and Waterhemp in the Pacific Northwest: Glyphosate Resistance Confirmation and Implications for Crop Production - Albert Adjesiwor
Mesotrione and Simazine-Based Tank-Mixes for Late-Season Control of Doveweed in Bermudagrass Turf - Pawel Petelewicz
Simulation-Based Nozzle Density Optimization for Maximized Efficacy of a Machine-Vision Weed Control System for Applications in Turfgrass Settings - Pawel Petelewicz
Implementing Digital Multispectral 3D Scanning Technology for Rapid Assessment of Hemp (Cannabis sativa L.) Weed Competitive Traits - Tyler Campbell
Farmer Experiences with Soil Tarping Across South Dakota - Hannah Voye
Moderator
ZM

Zelalem Mersha

Virginia State University
Tuesday September 24, 2024 11:59am - 1:50pm HST
Lehua Suite

12:00pm HST

GG 1 - Chromosome Level Assemblies of Phoenix dactylifera L. 'Medjool' and 'Deglet Noor'
Tuesday September 24, 2024 12:00pm - 12:10pm HST
Date palm (Phoenix dactylifera L.) is one of the oldest cultivated perennial woody plant species with significant agricultural and economic importance. Date has its center of origin in the Middle East, spreading in ancient times to North Africa and South Asia and later to other hot, arid areas. Dates are a strict dioecious evergreen, obligate outcrossing, and highly heterozygous monocot species that are typically vegetatively propagated. ‘Medjool’ and ‘Deglet Noor’ are the most widely grown date cultivars in the United States and are also important at the global level. Despite their economic values, genomic studies have been hampered due to lack of available assembled genomes. To facilitate future genomic studies, genomes for ‘Medjool’ and ‘Deglet Noor’ were assembled using Dovetail® HiFi and Omni-C® technologies. ‘Medjool’ had a total length of 757 Mb comprising 899 scaffolds (L50 : 7, N50 : 37 Mb) with a BUSCO completeness score of 97.65 %, and ‘Deglet Noor’ had a total length of 772 Mb comprising 1287 scaffolds (L50 : 9, N50 : 33 Mb) with a BUSCO completeness score of 97.65 %.
Speakers
YH

Yoko Hiraoka

University of California Riverside/USDA-ARS
Co-authors
RK

Robert Krueger

United States Department of Agriculture
NA
Tuesday September 24, 2024 12:00pm - 12:10pm HST
South Pacific 2

12:00pm HST

O/LT 1 - Evaluation of Native Azaleas for Container Production in the Mid-Atlantic
Tuesday September 24, 2024 12:00pm - 12:10pm HST
Deciduous azaleas (Rhododendron spp.) are native to the Eastern United States and have potential for increased adoption in the ornamental nursery and landscape market. However, plant availability is currently limited and trials on the growth and performance of each species are lacking. Furthermore, seed propagation is the common production method for native azaleas, which can result in phenotypic variation and a longer period of time to produce a saleable product, relative to vegetative propagation. Under optimum growing conditions, native azaleas can be low-input plants with minimal insect and disease issues. However, they can also be susceptible to summer heat stress and require well-drained soils and partial-shade similar to their indigenous growing environments in order to thrive. To determine which species may be most well-adapted to typical container nursery production practices, container trials were established to evaluate nine different species of native azaleas, including R. arborescens, R. atlanticum, R. austrinum, R. canescens, R. cumberlandense, R. flammeum, R. periclymenoides, R. prunifolium, and R. vaseyi, grown in both full sun and 50% shade conditions. Seed-grown one-year old liners of each of the nine different species were established in one-gallon containers and evaluated for growth rate and physiological characteristics, such as leaf chlorophyll content and normalized difference vegetation index (NDVI), comparing plants grown in full sun vs. 50% shade. In year two, bloom dates and number of blooms per plant in full sun vs. 50% shade were compared. R. atlanticum demonstrated the greatest potential for commercial production, especially when grown under 50% shade conditions, based on growth rate and average number of blooms per plant. These results suggest that R. atlanticum may be a reliable species of native azalea for growers to commercially produce for this growing market segment, while other species may still have potential, albeit with additional attention to their specific production requirements.
Speakers
WE

William Errickson

Rutgers University
Co-authors
TW

Timothy Waller

Rutgers University
Timothy J Waller, Ph.D. is serving in his fourth year as the Commercial Nursery Agent of Rutgers Cooperative Extension in southern NJ, based out of Cumberland County. Tim has a Ph.D. in Plant Biology with a focus on fungal plant pathology and has been a licensed pesticide applicator... Read More →
Tuesday September 24, 2024 12:00pm - 12:10pm HST
Kahili

12:00pm HST

WCPM 1/HEMP - Farmer Experiences with Soil Tarping Across South Dakota
Tuesday September 24, 2024 12:00pm - 12:10pm HST
Soil tarping is a weed control method used by innovative farmers across the globe. Strategies used by farmers vary in terms of tarping material, time of application, length of time soil is covered, and the production goal. Solarization is a tarping technique that uses clear greenhouse plastic to harness light and energy from the sun to germinate weed seeds in the soil and exhaust the weed seed bank prior to a growing season. Occultation is another tarping technique that uses opaque tarps to warm the soil and stop light from germinating weed seeds or encouraging plant growth beneath the tarp. Researchers have taken an interest in exploring solarization and occultation impacts on weed suppression and soil health. During the 2023 and 2024 growing season, South Dakota State University soil tarping researchers collaborated with farmers across South Dakota to gain insight in farmer application of tarps. Farmer collaborators in South Dakota were each supplied with three tarp materials: black silage tarp, white silage tarp, and clear greenhouse plastic. Each farmer was told to use the tarp how they saw best fit for their operation. Farmers were given the opportunity to engage in field days and presentations to learn more about soil tarping. Each growing season, farmers worked with a team of researchers to collect data on soil temperature, moisture, and nitrogen. This data was collected through soil samples and HOBO moisture and temperature sensors that logged values hourly. Farmers also provided observations, photos, and dates for tarp removal and application along with comments on how well tarping fit into their system. While research studies can provide important details of tarping impacts on weed suppression and soil health, it is important to showcase the reality of how applicable this technique is for farmers in the real world.
Speakers
HV

Hannah Voye

South Dakota State University
Co-authors
KL

Kristine Lang

South Dakota State University
RB

Rhoda Burrows

South Dakota State University
NA
Tuesday September 24, 2024 12:00pm - 12:10pm HST
Lehua Suite

12:00pm HST

Exhibitor Talk: CID Bio-Science Inc
Tuesday September 24, 2024 12:00pm - 12:15pm HST
Tuesday September 24, 2024 12:00pm - 12:15pm HST
Coral 5

12:00pm HST

TCHG 1/ADMIN - Assessing “Teaching Effort” to Ensure Fairness and Equity Across Diverse Course Types
Tuesday September 24, 2024 12:00pm - 12:15pm HST
An ongoing and challenging issue for all administrators who have to assign teaching responsibilities is assessing “effort” associated with different types of courses. While it is abundantly clear that different amounts of effort go into lecture classes versus lab classes, we still frequently talk about teaching responsibilities as the “number of classes taught per semester.” In the department of Horticulture and Landscape Architecture at Purdue University, we faced this challenge across lecture courses, lab courses and Landscape Architecture studio classes. We undertook a year-long effort to assign “effort” values to each of our classes. In this presentation we will discuss our philosophy and approach to this undertaking, including how we engaged the entire department in the process. We ultimately developed a complex spreadsheet (currently being converted to an interactive database) that assigns points to classes based on number of contact hours, preparation work, service learning or experiential experience, grading/management workload, and class size. We then used this information to determine where additional support, in the form of graduate or undergraduate student TAs or staff, was most needed to create equity across teaching loads. This work is ongoing and needs to be updated annually based on changes in course structures and sizes and teaching assignments. In this presentation, we will share the database we created to make annual updates easy and transparent to everyone in the department.
Speakers
LP

Linda Prokopy

Purdue University
Co-authors
KO

Kathryn Orvis

Purdue Univ
SR

Sean Rotar

Purdue University
NA
Tuesday September 24, 2024 12:00pm - 12:15pm HST
South Pacific 4

12:00pm HST

Plant Growth and Culture Collaboration Session
Tuesday September 24, 2024 12:00pm - 1:00pm HST
A forum for discussion of potential collaborations with regards to plant growth and culture – i.e. propagation, root growth, water management, weed control, PGRs, plant nutrition, etc.
Tuesday September 24, 2024 12:00pm - 1:00pm HST
Coral 4

12:00pm HST

Administrators Luncheon
Tuesday September 24, 2024 12:00pm - 2:00pm HST
Advance ticket purchase is required.
ASHS Administrators Luncheon Agenda
  • Institution representative introductions
  • Faculty retirement and hires
  • Current or upcoming faculty/administration searches
  • Undergraduate and graduate enrollment trends
  • New/special efforts or programs at your institution
  • Election of New Officer - Secretary

Tuesday September 24, 2024 12:00pm - 2:00pm HST
Hibiscus 1

12:10pm HST

GG 1 - Development of Haplotype-Phased, Chromosome-scale Genomes for Pomegranate
Tuesday September 24, 2024 12:10pm - 12:20pm HST
Pomegranates (Punica granatum L.) are a significant fruit crop globally, gaining traction due to their high nutritional value and many uses outside of consumption. Despite increasing interest, genetic resources for pomegranates lag behind other crops. Developing these resources can enhance breeding efficiency and deepen genomic understanding. To address this, we sequenced the genomes of two cultivars: 'Azadi', known for its robust fruit rot resistance, and 'Peppy Le Pom', a dwarf variety with short juvenility. Using the PacBio Revio Platform, we generated HiFi reads with 30x coverage and employed Hi-C for sequencing. Leveraging hifiasm's Hi-C integrated assembly method, we assembled two haplotypes for the genome of each cultivar. For 'Peppy Le Pom', we utilized 10.03 Gb of PacBio HiFi reads and 30 Gb of Hi-C data and constructed two haplotypes with eight chromosome-length scaffolds each, totaling 304.9 Mb and 318.7 Mb, with a BUSCO score of 90.3% and 92.3%, respectively. For 'Azadi', we utilized 10.08 Gb of Pacbio HiFi reads and 30 Gb of Hi-C data and assembled two haplotypes with eight chromosome-length scaffolds, measuring 305.5 Mb and 318.1 Mb, with a BUSCO score of 91.0% and 92.6%, respectively. Chromosome sizes of these pomegranate cultivars range from 27.1 Mb to 62.4 Mb. Notably, these results closely align with the previously published draft genome of the 'Tunisia' cultivar. These phased, chromosome-scale genomes will facilitate further exploration of traits of interest for pomegranate breeding, such as disease resistance, dwarfing, and short juvenility. The genomic resources established here pave the way for accelerated advancements in pomegranate research and breeding.
Speakers
AS

Alexander Schaller

University of Florida
Co-authors
JC

John Chater

University of Florida
ZD

Zhanao Deng

University of Florida
Tuesday September 24, 2024 12:10pm - 12:20pm HST
South Pacific 2

12:10pm HST

O/LT 1 - Facilitating Pollinator Conservation in Agriculture: Understanding Grower Needs in Obtaining IPM Certification
Tuesday September 24, 2024 12:10pm - 12:20pm HST
Due to global concerns over the decline in pollinator populations, Walmart U.S. has initiated a policy requiring all produce and floral products sold in stores to be sourced from vendors who have obtained an Integrated Pest Management (IPM) certification from an approved third-party organization by 2025. The certification process for growers entails comprehensive documentation of operational practices, pesticide use and mitigation, and evaluation of on-farm pollinator habitat. However, this process is cumbersome for growers to conduct alone, necessitating assistance from a third-party such as Extension agents and staff. Furthermore, identifying and expanding existing pollinator habitat is often unfamiliar to growers, presenting a significant barrier in the application process and hindering the expansion of pollinator habitat. This project seeks to assess the needs of growers in navigating the IPM certification process and understanding the barriers they face. Future work will include the development of accessible consulting services that supports North Carolina growers throughout the certification process while also equipping them with necessary skills and knowledge to enhance and expand pollinator habitat.
Speakers
avatar for Madison Love

Madison Love

North Carolina State University
My research is uniquely focused on conserving natural resources and fostering environmental stewardship. This is achieved through actively engaging communities in pollinator conservation efforts, supporting growers in adopting integrated pest management (IPM) along with creating pollinator... Read More →
Tuesday September 24, 2024 12:10pm - 12:20pm HST
Kahili

12:10pm HST

WCPM 1/HEMP - Evaluating Fall Cover Crops for Enhanced Soil Properties and No-Till Weed Suppression in Chickpea Production in Virginia
Tuesday September 24, 2024 12:10pm - 12:20pm HST
Cover crops offer multifaceted benefits including soil health improvement, nutrient management, erosion control, and suppression of pests, diseases and weeds. This study examined the impact of fall cover crop (FCC) for enhanced soil properties and suppression of weeds and diseases, top priorities for chickpea growers. FCC was comprised of winter rye alone (in 2021) or in combination with hairy-vetch (in 2022-2023). To assess soil property changes, 5 quadrants (50 cm x 50 cm) representing each dense (≥ 96%), poor (10-35%) and no-growth (0%) FCC areas were sampled annually in April. Soil nutrients and biomass accumulation was measured and compared. For weed suppression, five treatments were compared: till- green manure (GM), GM plus pre-emergence herbicide (GMH), and no-till after termination via crimp-mulch (CM), kill-mulch (KM) or mow-mulch (MM). In 2023, significantly higher fresh (514 t/ha) and dry (140 t/ha) biomass was added to the soil from densely and sparsely FCC areas, respectively. Weed suppression was better on GMH than GM for the first 6-8 weeks but reached an average of ≥ 67.5% when monitored 92 days after chickpea planting. Similarly, no-till planted chickpeas after CC terminations in 2021 suppressed weeds during early stages but not in 2022. In both years, it was not possible to harvest chickpeas after no-till due to overwhelming weed infestation. Although added organic matter was evident across all years, FCC alone did not significantly suppress weeds in 2022 and 2023. Slightly different results are anticipated with adjustments in termination timing and conditions favoring mulch establishment in 2024 growing season.
Speakers
ZM

Zelalem Mersha

Virginia State University
Tuesday September 24, 2024 12:10pm - 12:20pm HST
Lehua Suite

12:14pm HST

Postharvest 1/Produce, Quality, Safety and Health Properties (PH 1/QUAL)
Tuesday September 24, 2024 12:14pm - 1:45pm HST
Identification of Genes Associated with the Chilling Prerequisites for Ripening in European Pear - Adwaita Parida
Effects of Cooling Delay and Harvest Maturity on ‘Gem’ Pear Internal Breakdown Development - Janet Turner
Efficacy of Ultraviolet Radiation for Control of the Mucor Rot Pathogen in Post-harvest Anjou and Bartlett Pears - Shawn McMurtrey
Preliminary Insights Into the Effects of Various Technologies of 1-methylcyclopropene (1-MCP) “AnsiP®” on Apple Fruit Quality During Shelf Life - Yosef Al Shoffe
Pre-Storage Ambient Temperature Delay Reduces Lenticel Blotch by Mediating Metabolic Alteration in Cold-Stored ‘Summer Prince’ Apples - Hyowon Park
1-Methylcyclopropene from HarvestHold Fresh® impact on ‘Red Delicious’ apple during cold storage - Ozge Horzum
Speakers
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Tuesday September 24, 2024 12:14pm - 1:45pm HST
South Pacific 1

12:14pm HST

Vegetable Crops Management 1 (VCM 1)
Tuesday September 24, 2024 12:14pm - 1:50pm HST
Effect of Biostimulants on Emergence and Growth of Watermelon (Citrullus lanatus) Transplants. - Evan Christensen
Evaluation of Specialty Cucumber Cultivars in a High Tunnel Production System - Jacob Arthur
Are Locally Sourced Biochar and Poultry Litter the Solution to Improving Soil Health and Sustainably Producing Tomatoes? - Emilio Suarez Romero
Is Trellising Beneficial to High Tunnel Melon Yield? - Lewis Jett
Interseeded Clover Does Not Impact Pumpkin Yield - Charlie Rohwer
Protecting New Mexico’s Chile Crops from Curly Top Virus through Agrivoltaics - Mariela Estrada
Integrating High-resolution Satellite Imagery to Monitor Crop Growth and Yield: A Case Study of Japanese Squash and Onion in Hollister, California - Elia Scudiero
A New Tool to Manage Water and Nutrients in High Tunnel Tomato Production - Rebecca Brown
Soil Moisture Sensors Allow for Resilient Tomato Production in Organic Systems - Andre Luiz Biscaia Ribeiro da Silva
Physiology of Heat Tolerant Tomatoes: Transplanting Through Harvest - Courtney DeKalb-Myers

Moderator
avatar for Charlie Rohwer

Charlie Rohwer

Scientist, University of Minnesota
Tuesday September 24, 2024 12:14pm - 1:50pm HST
Nautilus 1

12:15pm HST

PH 1/QUAL - Identification of Genes Associated with the Chilling Prerequisites for Ripening in European Pear
Tuesday September 24, 2024 12:15pm - 12:25pm HST
The pear (Pyrus communis L.) has been classified as a climacteric fruit, undergoing a ripening process characterized by a transition from system-I to system-II ethylene production. This transition denotes a change in the regulation of ethylene biosynthesis from being auto-inhibitory to auto-stimulatory process. Increased ethylene production during climacteric ripening is accompanied by a corresponding rise in respiration. Pears require chilling for ripening, and the duration of chilling necessary for ripening varies among cultivars. ‘Bartlett
Speakers Co-authors
Tuesday September 24, 2024 12:15pm - 12:25pm HST
South Pacific 1

12:15pm HST

VCM 1 - Effect of Biostimulants on Emergence and Growth of Watermelon (Citrullus lanatus) Transplants.
Tuesday September 24, 2024 12:15pm - 12:25pm HST
The impacts of climate change and drought threatens water supplies that are necessary for watermelon production. Most production in the U.S. is seedless watermelon, typically grown in greenhouses and transplanted due to poor seed establishment in the field. Given the significance of high-quality transplants for the industry, we conducted a study to evaluate whether biostimulant products would improve transplant quality. In this study seven biostimulant products were tested on greenhouse-grown watermelon seedlings to measure seedling emergence and growth. Three bacterial (Continuum, Spectrum Ds, and Tribus Original), two mycorrhizal (MycoApply Endo, and Mighty Mycorrhizae), one humic (Huma Pro 16), and one seaweed extract product (Kelpak) were used. All products, except Kelpak, were incorporated into the growing media before sowing. Kelpak was applied at the first true leaf stage as a soil drench. Leaf area and root/shoot fresh and dry weight were measured over a 30-day period after stand establishment and data underwent analysis of variance (ANOVA) using SAS statistical software. Though some biostimulant products tended to have higher shoot and root weight they were not always significantly different, and the results were variable from trial to trial and analysis is ongoing.
Speakers
EC

Evan Christensen

Utah State University
Tuesday September 24, 2024 12:15pm - 12:25pm HST
Nautilus 1

12:15pm HST

Interest Group Session: Growing Together: Enhancing Accessibility, Engagement and Inclusion in the Horticulture Society
Tuesday September 24, 2024 12:15pm - 1:45pm HST
Growing Together: Enhancing Accessibility, Engagement, and Inclusion in the Horticulture Society

Accessibility, inclusion, and engagement are foundational to any society, including our own American Society for Horticultural Sciences, ensuring that every community member can contribute to and benefit from the diverse array of knowledge, perspectives, and experiences within the fields of horticulture and plant sciences. This special interest group session is dedicated to fostering these principles within the broader horticultural society, the green industry, and the gardening community. The meeting aims to unite ASHS members who share a passion for the art, science, and business of plants, gardens, landscapes, and gardening, making these accessible to everyone, irrespective of their abilities or backgrounds.

Committee members Heather Kirk-Ballard, Assistant Professor of Consumer Horticulture at Louisiana State University and Sam Humphrey, Graduate Research Association at North Carolina State will lead a discussion to address key topics such as strategies for creating more inclusive systems. We will discuss practical ways to interact, cultivate, and enhance diversity within our workforce and society, aiming to break down barriers that can perpetuate disparities.

In this session, we will discuss the findings from the recent ASHS DEIJA committee climate survey that examined the feedback from members regarding the impact of diversity, equity, inclusion, and justice within the American Society for Horticultural Sciences. We acknowledge the resistance some may have towards the formation of a diversity and inclusion committee. As many organizations face similar backlash against DEI initiatives, often due to misunderstandings or perceived threats to the status quo, it is essential to engage in transparent and constructive dialogue. Our aim is to clarify the objectives and benefits of DEI, underscoring its role in promoting fairness, opportunity, and representation for all members of the organization.

The session will include discussions about accessible practices, presentations and workshops that can be designed for individuals with physical disabilities or mobility issues. Strategies to increase participation from diverse community members. This could involve outreach programs for schools, collaboration with a greater community, and events that cater to a wide demographic. Developing programs that cater to people of all ages, abilities, and ethnic backgrounds. This may include bilingual garden tours, programs for the visually impaired, and workshops tailored for elderly gardeners. The meeting also provides a platform for members to share their experiences and best practices in creating inclusive environments. There will be networking opportunities to foster collaborations and partnerships among participants, aiming to build a supportive community that values diversity and inclusion in horticulture. The objective of this meeting is to establish clear, actionable steps that the society can implement to enhance accessibility and engagement. This will ensure that all members of the broader community can fully benefit from the opportunities offered by horticulture.

Coordinator(s)
  • Heather Kirk Ballard, SPESS, School of Plant, Environmental and Soil Sciences, Baton Rouge, EBR, United States
  • Samson Humphrey, NCSU, Raleigh, North Carolina, United States

Moderator
Tuesday September 24, 2024 12:15pm - 1:45pm HST
Coral 1

12:20pm HST

GG 1 - In Planta Transformation Efficiency Assessment of Different Agrobacterium Strains and Explant Types in Catharanthus rose
Tuesday September 24, 2024 12:20pm - 12:30pm HST
Catharanthus roseus (L.) G. Don is a common ornamental crop worldwide due to its high tolerance to drought and heat. The researches on Agrobacterium-mediated transformation of C. roseus are few, and mostly focus on the production of secondary metabolites in roots. Furthermore, the organogenesis from callus to plantlet is frequently unstable which limits the study on entire plant, especially on flowering. The objective of this study is to evaluate the in planta transformation survival rate in different explants and Agrobacterium strains. C. roseus ‘Cora XDR White’ seeds were cultivated in vitro till the cotyledon expanded. Plantlets and cotyledonary nodes were respectively inoculated with two Agrobacterium strains, GV3101 or LBA4404 harboring the binary vector pHEE401E. Explants were co-cultivated in 1/2 MS medium for three days. After washing with sterile water and cefotaxime, the explants were first placed in a medium containing cefotaxime, then were transferred to a same medium that was further added hygromycin. During the elimination and selection, each cotyledonary node turned brown. In the process of subculture, necrotic parts were removed. Result showed that the survival rate of plantlets was 5% in GV3101 treatment. However, LBA4404 ones eventually got brown.
Speakers
TH

Ting Hsuan Huang

Department of Horticultural Science, National Chiayi University
Co-authors
RS

Rong Show Shen

National Chiayi University
NA
YH

Yang Hsin Hsu

National Chiayi University
NA
YC

Yi Chien Lu

National Chiayi University
Tuesday September 24, 2024 12:20pm - 12:30pm HST
South Pacific 2

12:20pm HST

O/LT 1 - Relationship between Soil Water Content, Quantum Efficiency, Stomatal Conductance and Stem Water Potential in Salvia guaranitica ‘Black and Blue’
Tuesday September 24, 2024 12:20pm - 12:30pm HST
Perennials are an important component in north-central Texas landscapes, providing color and foraging for local pollinators. However, severe summer drought and a rapidly growing urban environment forces limitations on water availability for landscape irrigation. Therefore, we need to evaluate the impact of deficit irrigation on landscape plant performance. Salvia guaranitica ‘Black and Blue’ is a perennial known to perform well in north-central Texas summers, and it attracts numerous pollinators, including bumblebees, butterflies, and hummingbirds. Twelve beds were created in four blocks, with three beds per block and one plant planted per bed. Within each block, irrigation was applied at one of three levels, 60% of evapotranspiration (ET), 30% of ET and no irrigation. Soil moisture monitors [time domain reflectometry (TDR), 10HS, Onset Computer Corp., Bourne, MA] and a handheld moisture meter (TDR, Fieldscout 350, Spectrum Technologies, Aurora, IL) were used to measure water content by volume (Θv). Quantum efficiency (ΦPSII) and stomatal conductance (gs) were measured using a fluorometer/porometer (LI-600, LiCor Corp., Lincoln, NE), and stem water potential of each plant was measured using a pressure chamber (Model 615, PMS Instrument Company, Albany, OR) on a weekly basis. Surprisingly, soil moisture levels in the 30% treatment (0.10 m-3·m-3) were the lowest, with 60% at 0.25 m-3·m-3) and no irrigation at 0.14 m-3·m-3. Quantum efficiency was similarly lower in 30% (0.60), compared to 0.72 and 0.69 for the 60% and unirrigated plots, respectively. Stomatal conductance was similar across all treatments. Stem water potentials were highest in plants receiving 30% (800 kPa), compared to 380 kPa in 60% and 360 kPa with no irrigation. Across all treatments, plant performance was correlated to soil water content, (ΦPSII P=0.03, r=0.24; gs P=0.05, r=0.22; kPa P=0.003, r=-0.33). Based on this study, Salvia guaranitica ‘Black and Blue’ should be irrigated at 60% of ET for best plant performance during summer heat and drought.
Speakers
avatar for Lindsey Trinkle
Co-authors
Tuesday September 24, 2024 12:20pm - 12:30pm HST
Kahili

12:20pm HST

WCPM 1/HEMP - Impact of Cover Crops and Herbicides on Early Season Weed Control and Sweetpotato Storage Root Yield.
Tuesday September 24, 2024 12:20pm - 12:30pm HST
Sweetpotatoes (Ipomoea batatas L.) are among the most important food crops worldwide, but production in Missouri is limited. Weed competition, especially early in the growing season, is a major factor impacting sweetpotato yields. The objective of this study was to optimize early season weed control in sweetpotatoes using fall seeded cover crops and spring applied herbicides. Cover crops, cereal rye (Secale cereale L.) or winter wheat (Triticum aestivum L.), were seeded in the fall. Before sweetpotato transplanting the following spring, glyphosate was applied to terminate cover crop growth along with flumioxazin as a residual herbicide. In designated treatments, S-metolachlor was applied 3 weeks later to extend residual activity. A total of eight treatments, including an untreated control, and a second control consisting of herbicides followed by tillage and hand-weeding as Missouri standard practice, were arranged in a randomized complete block design with four replications. Sweetpotato ‘Beauregard’ slips were transplanted in early June 2023. By 4 weeks after transplanting (WATr), weed biomass in cover crop plus herbicide plots was reduced by 99.3% and 86.3% for broadleaf and grass weeds, respectively, compared to the untreated control. An orthogonal test found that sweetpotato production in plots that received winter wheat as cover crop resulted in a significantly higher yield compared to plots that received cereal rye as a cover crop. Winter wheat combined with flumioxazin applied PRE and S-metolachlor applied as an overlapping residual herbicide demonstrated the greatest yield among all treatments, resulting in over 200-fold greater yield compared to the untreated control. The Missouri standard practice, represented as the weed-free control, produced statistically the same yield as the best treatment. However, this was the most time-consuming and labor-intensive practice and would be challenging for commercial production. Collectively, our results suggest that sweetpotato production in Missouri should consider integration of cover crops and herbicides to allow strong establishment of sweetpotato vines early in the early growing season, and hence ensure higher profitability without intensive labor inputs.
Speakers
RN

Richard Noel Torres

University of Missouri - Columbia
Co-authors
RS

Reid Smeda

University of Missouri - Columbia
NA
XX

Xi Xiong

University of Missouri - Columbia
NA
Tuesday September 24, 2024 12:20pm - 12:30pm HST
Lehua Suite

12:20pm HST

Exhibitor Talk: BioChambers Inc
Tuesday September 24, 2024 12:20pm - 12:35pm HST
Tuesday September 24, 2024 12:20pm - 12:35pm HST
Coral 5

12:25pm HST

PH 1/QUAL - Effects of Cooling Delay and Harvest Maturity on ‘Gem’ Pear Internal Breakdown Development
Tuesday September 24, 2024 12:25pm - 12:35pm HST
‘Gem’ pear is a relatively new European pear cultivar with good fire blight resistance. Fruit can be eaten without ripening, either at harvest or upon removing from cold storage, when still crisp and juicy, or can be expected to ripen to a buttery melting texture after 30-60 days of regular-air (RA) storage (~30 °F). Although research initially indicated ‘Gem’ could be stored in RA conditions for 5 months with good quality retention, in practice ‘Gem’ storage has proved more challenging, primarily due to internal breakdown which can appear as early as 2 months after storage, either in RA or controlled atmosphere (CA) conditions. Additionally, with increasing commercial production of ‘Gem’, there is industry interest in extending storage beyond 5 months. This on-going study evaluates factors potentially influencing internal breakdown development, such as cooling delay (representing a delay of room temperature establishment at storage facility) and fruit maturity in year 1 and cooling delay and rate of controlled atmosphere (CA) establishment in year 2. In year 1, internal breakdown incidence was essentially absent for fruit harvested at 56 N flesh firmness but higher for fruit harvested at 44 N, especially where cooling was delayed. Fruit harvested at 56 N did not soften to below 18 N at 60 d storage, indicating a longer period of postharvest chilling is required for less mature fruit.
Speakers
JT

Janet Turner

Bio-Science Research Technician, USDA-ARS Hood River Worksite
Co-authors
KD

Kristal Dowell

USDA-ARS Hood River Worksite
NA
RL

Rachel Leisso

USDA-ARS Hood River Worksite
YD

Yu Dong

State Key Laboratory of Plateau Ecology and Agriculture
NA
Tuesday September 24, 2024 12:25pm - 12:35pm HST
South Pacific 1

12:25pm HST

VCM 1 - Evaluation of Specialty Cucumber Cultivars in a High Tunnel Production System
Tuesday September 24, 2024 12:25pm - 12:35pm HST
Cucumbers are popular and high-value vegetable crops mainly marketed through local food markets for fresh consumption. Vegetable growers in Mississippi mainly operate on small to medium size farms. High value crops including tomatoes, peppers and cucumbers could be grown to increase competitiveness. Specialty cucumber cultivars including the parthenocarpic and mini types are in high demand due to their superior eating quality, these are often produced in protected environments like high tunnels or greenhouses. The objective of this study is to evaluate specialty cucumber cultivars and identify cultivars for superior yield and quality in the local climate under protected culture. This study was conducted in a high tunnel production system located at Mississippi State University through two growing seasons in 2022 and 2023. Twenty cucumber cultivars were evaluated including ten long Dutch/English slicer types: ‘Asteroid Long’, ‘Bologna Long’, ‘Boncanale Long’, ‘Davida Long’, ‘Durance Long’, ‘Georgia’, ‘Kasja Long’, ‘Tyria Long’, ‘Verdon Bio Long’, ‘Verdon Long’; five mini types: ‘Jawell Mini’, ‘Katrina’, ‘Manar Mini’, ‘Picolino’, ‘Socrates’; and four Asian types: ‘Itachi’, ‘Nokya’, ‘Unagi’, ‘Wokue’. The last cultivar ‘Striped Armenian’ is not a true cucumber and is actually part of the melon family. Plants were grown in 6-gallon containers using a modified drop line trellis system. Plant vegetative growth that was measured included plant height, stem diameter as well as soil plant analysis of development (SPAD). Cucumber fruits were harvested twice weekly, weighed for individual fruit weight, counted, and separated into marketable yield and unmarketable yield. Various fruit quality characteristics including: fruit diameter, fruit length, skin color, soluble solids content and fruit firmness were collected twice in each growing season. Cultivars varied in marketable and unmarketable yields in both growing seasons. In 2022, the cultivar ‘Picolino’ produced the highest marketable yield of 4.79 kg per plant with a majority of the other cultivars having statistically similar marketable fruit yields ranging from 2.87 kg in ‘Unagi’ to 4.75 kg in ‘Katrina’. The lowest marketable yield was produced by ‘Striped Armenian’ with 2.05 kg of marketable fruit for the entire growing season. Fruit quality parameters including soluble solids content, firmness, and fruit length had significant differences between cultivars. The cultivar ‘Kasja Long’ produced fruits with the highest soluble solids content of 4.18 °Brix, the other cultivars in this study had values ranging from 2.47 °Brix to 4.12 °Brix. The cultivars ‘Itachi’ and ‘Socrate’ produced the firmest fruit with values of 6.75 N and 6.70 N, respectively.
Speakers
JA

Jacob Arthur

Mississippi State University
Co-authors
GB

Guihong Bi

Mississippi State University
TL

Tongyin Li

Mississippi State University
NA
Tuesday September 24, 2024 12:25pm - 12:35pm HST
Nautilus 1

12:29pm HST

Pomology 1 (POM 1)
Tuesday September 24, 2024 12:29pm - 1:20pm HST
Consumer Preference and Willingness-to-Pay for Pawpaw Value-Added Products - Sheri Crabtree
Promising Advanced Selections from Kentucky State University’s Pawpaw (Asimina triloba) Breeding Program. - Jeremy Lowe
Assessment of Fruit Quality and Value-added Potential of 16 Pawpaw Cultivars and Advanced Selections - Kirk Pomper
Effects of Temperature and Light on Sunburn, and Preventing the Sunburn Damage by Chemical Suppressants in ‘Fuyu’ Sweet Persimmons - Yunji Shin
Crown Gall Associated with Higher Risk of New Butt Rot Pathogen in California Almond Orchards - Raymond Mireles

Moderator
KP

Kirk Pomper

Dean College of Agriculture, Kentucky State University
Tuesday September 24, 2024 12:29pm - 1:20pm HST
Coral 2

12:29pm HST

Viticulture and Small Fruits 1 (VSF 1)
Tuesday September 24, 2024 12:29pm - 1:30pm HST
Identification and Prevalence of Grapevine Virus Diseases (GVD) in North Carolina - Kimberly Heagy
Learning Sustainable Edible Gardening through Hands-on Approach with Muscadine Grapes - Claude Judy Jean
Creating a Practical Approach for Wine Grape Grower to Predict Grapevine Water Status by Precision Viticulture Technologies - Runze Yu
Effect of Planting Distance on PD Resistant Predominantly Vitis Vinifera Grape ‘502-20’ During the Years of Establishment - Elina Coneva
Genetics of Adventitious Root Formation in Dormant Bud Cuttings of Grapevines - Sadikshya Sharma
Evaluation of Cordon Training System in Blackberry Production - Jayesh Samtani

Moderator
CJ

Claude Judith Jean

University of Florida
Tuesday September 24, 2024 12:29pm - 1:30pm HST
South Pacific 4

12:29pm HST

Undergraduate Student Poster 1 (UG 1)
Tuesday September 24, 2024 12:29pm - 2:10pm HST
A Mentor-Mentee Undergraduate Scientific Communications Course - Danielle Jaden Yamagata Santos
Growth and Volatile Compounds on Thai Herbs at Different Cultivation Systems in Vertical Farming - Akira Kakai
Growth, Anthocyanin Content and Its Gene Expression in Purple Color Paprika Fruit Applying Blue Light at Night - Ryuhei Mitsuzuka
The Effect of Mixing Artificial Seawater into Hydroponic Solution to Tomato Fruit Growth and Ion Contents - Miyuki Baba
Detection of Postharvest Quality of Cut Roses using Vis/NIR Spectroscopy - Ji Yeong Ham
Developing Utah’s Own Sap Drinks - Catherine Sun
Effect Of Temperature Alterations On Phytochemicals Accumulation Among Two Variety Of Feverfew Cultivars - Jalynn Greer
Increased Airflow Improves Yields of High Density Indoor Micro Dwarf Tomato - Matthew Arrington
Assessing the Impact of Urban Environments on the Biomolecular Composition of 'Mosco' Chili Peppers - Kathryn Braun
Growth and Physiology of Three Buckwheat Cultivars under Reduced Substrate Water Contents - Sawyer Zook

Tuesday September 24, 2024 12:29pm - 2:10pm HST
South Pacific 3

12:30pm HST

GG 1 - Native Southern Red Aroniaberry (Aronia arbutifolia) Response to Chill Hours in Georgia
Tuesday September 24, 2024 12:30pm - 12:40pm HST
Aroniaberry or chokeberry (Aronia sp., Rosaceae) is an attractive deciduous tree-like shrub. Native to eastern and central United States, red aroniaberry (A. arbutifolia) is more predominant in the southern part of the distribution. Bright red fruits, proliferous white flowers in spring, and attractive fall color, make A. arbutifolia a native shrub with ornamental potential. Most of the aroniaberry ornamental varieties available in the market are selections or hybrids of black aroniaberry (A. melanocarpa), they produce black fruit, and do not perform well in sub-tropical climates. We collected triploid and tetraploid A. arbutifolia from five different locations in South Georgia and evaluated their flowering period, fruit production, and response to chill hours in Griffin, GA (Zone 8a, Piedmont region). Plants were exposed to 1000, 800, 600, 400, or 0 chill hours and planted in the field in April of 2023. Flowering timing had a strong correlation with chill hours; plants with chill hours below 600 hrs. presented less flowers and flowering was not uniform.
Speakers
LL

Leynar Leyton

University of Florida
Co-authors
BP

Bodie Pennisi

University of Georgia
NA
CR

Carol Robacker

University of Georgia
NA
Tuesday September 24, 2024 12:30pm - 12:40pm HST
South Pacific 2

12:30pm HST

O/LT 1 - Effect of Coconut Coir and Biochar Media on Ornamental Plant Growth and Nutrient Leaching
Tuesday September 24, 2024 12:30pm - 12:40pm HST
The growing demand for container ornamental plants opens new opportunities for nurseries to expand their business. However, expecting to improve plant quality, growers often overapply fertilizer and water. Excessive fertilizer application and overwatering can result in nutrient leaching and runoff. In addition, growers heavily rely on unsustainable sphagnum moss as a medium for growing their plants. Replacing sphagnum moss with coconut coir may increase production sustainability, and incorporating biochar may have potential to adsorb excess nutrients, thus lowering fertilizer concentration in leachate. In this study, we explored the suitability of using various mixtures of coconut coir and biochar for growing goldenrod, lavender, and chrysanthemum plants for two growing seasons. Results indicated that utilizing pine bark and coconut coir did not hinder plant growth and development compared to a traditional mixture of pine bark and sphagnum moss for any of the plants studied. Also, inclusion of 10% biochar did not enhance growth, nor did it reduce nitrate nitrogen and phosphorus concentration in container leachate. Biochar did not reduce nutrient leaching in this study. However, coconut coir was found to be a suitable substitute for sphagnum moss in container nursery production.
Speakers
SB

Saroj Burlakoti

Utah State University
Co-authors
KK

Kelly Kopp

Utah State University
NA
LS

Lance Stott

Utah State University
NA
SP

Shital Poudyal

Utah State University
NA
Tuesday September 24, 2024 12:30pm - 12:40pm HST
Kahili

12:30pm HST

POM 1 - Consumer Preference and Willingness-to-Pay for Pawpaw Value-Added Products
Tuesday September 24, 2024 12:30pm - 12:40pm HST
The North American pawpaw (Asimina triloba) is the largest edible tree fruit native to North America, with a flavor resembling a unique tropical-like blend of mango and banana. Commercial production and consumer interest in pawpaw is on the rise in the US and worldwide. Fresh pawpaw fruit has a short shelf life and does not store or ship well. Value-added products represent a great potential market to both diversify offerings of products containing pawpaw, and provide shelf-stable products that could be available year-round and circumvent the storage and shipping challenges of fresh fruit. Pawpaws can be utilized in many value-added products, including ice cream, yogurt, jam, custard, baked goods, hot sauces, wine, beer, and brandy. A pawpaw value-added product tasting was conducted in September 2023 at the Kentucky State University Research and Demonstration Farm as part of the annual Pawpaw Third Thursday Thing workshop. Participants tasted samples of slices of fresh pawpaw fruit of six varieties, pawpaw jam on crackers, and pawpaw ice cream. A survey was conducted evaluating preference and interest in purchasing pawpaw fruit, jam, and ice cream, and willingness to pay. The survey found that 93% of participants would be interested in purchasing pawpaw fruit at a farmers market, compared to 80% at a grocery store and 88% at an on-farm market or roadside stand. Ninety-five percent (95%) of participants would be interested in purchasing pawpaw jam if available in stores, and 95% of participants would also be interested in purchasing pawpaw ice cream if available in stores. Respondents would be willing to pay $2.20 per fruit, or $4.97 per pound for fresh pawpaw fruit. Respondents reported they would pay $7.22 for an 8 ounce jar of pawpaw jam, and $8.51 for a quart of pawpaw ice cream. Currently, pawpaw ice cream and jam are sold by very few retailers in specialty markets, so there is great opportunity for pawpaw producers to introduce high-value pawpaw products that are desired by consumers to their retail markets.
Speakers
SC

Sheri Crabtree

Horticulture Research and Extension Associate, Kentucky State University
Co-authors
JL

Jeremy Lowe

Kentucky State University
JN

Joni Nelson

Kentucky STate University
KP

Kirk Pomper

Kentucky State University
Dr. Kirk W. Pomper is the Professor of Horticulture in the College of Agriculture, Community, and the Sciences at Kentucky State University in Frankfort, Kentucky. As Horticulture Research Leader, his program is focused on research and Extension efforts toward developing pawpaw as... Read More →
MB

Matthew Behrends

Kentucky State University
Tuesday September 24, 2024 12:30pm - 12:40pm HST
Coral 2

12:30pm HST

UG 1 - A Mentor-Mentee Undergraduate Scientific Communications Course
Tuesday September 24, 2024 12:30pm - 12:40pm HST
TPSS 491 Scientific Communications is a new one-credit undergraduate course in the TPSS Department. It was offered for the first time in Fall 2023 with six undergraduate students. The objective was to enable personalized instruction and mentoring of students on their projects. Consulting with the instructor, each student decided on two projects to work on. Students indicated what specific feedback they were looking for, and the instructor provided individualized assistance. One-to-one meetings enabled more detailed personal instruction. Students were more motivated when working on their own projects. This course’s flexible meeting dates and times allowed tailoring it to each student’s schedule. TPSS 491 helped me to develop and complete personal projects that are crucial in professional development. The flexibility of the course allowed me to partake in one-on-one meetings that worked with my schedule as a full-time student which was one factor why I decided to take this course. Being able to receive personalized feedback on my projects allowed me to make constant improvements that made me feel confident in my work, especially as I plan to use these as tools to enter the professional setting after graduation. The course’s flexible scheduling and wide choice of projects were very appealing to me. As an upper-class student, I had multiple ongoing research projects, more classes than usual, and a research-based part-time position. Each commitment involved weekly meetings, assignments, and demanded a significant portion of my time and attention. However, the flexibility of the “To Be Determined” scheduling of the course created more freedom within my schedule, providing me with the necessary time to complete my other projects and courses. Having the choice to decide which projects to work on enabled me to receive valuable feedback on an important graduate school funding application and a research project. Without this flexibility, I might not have received as much feedback on these important parts of my academic journey. In conclusion, TPSS 491 is an important course for undergraduate students to receive valuable feedback from the instructor regarding scientific communication. TPSS 491 proved to be an invaluable course for me. The constructive feedback I received on my projects was instrumental in my personal and academic growth. This course allowed me to focus on projects that held significance for my academic and professional development and provided the flexibility needed to balance various commitments required to advance my experience as an early-career researcher.
Speakers
DJ

Danielle Jaden Yamagata Santos

Univ. of Hawaii at Manoa
NA
Co-authors
KK

Kent Kobayashi

Univ. of Hawaii at Manoa
KG

Koa Grabar

Univ. of Hawaii at Manoa
NA
Tuesday September 24, 2024 12:30pm - 12:40pm HST
South Pacific 3

12:30pm HST

VSF 1 - Identification and Prevalence of Grapevine Virus Diseases (GVD) in North Carolina
Tuesday September 24, 2024 12:30pm - 12:40pm HST
Grapevine virus diseases (GVD) are a leading cause of economic concern in the US grape and wine industry, including in North Carolina (NC). Visual vineyard observations in summer and fall of 2017 revealed GVD-like symptoms across European-style winegrowing regions in NC. These observations prompted a state-wide vineyard survey with two aims, (1) identify and assess the prevalence of common grapevine viruses in NC and (2) develop a GVD testing service for growers in NC. A vineyard survey was conducted after harvest (October
Speakers
KH

Kimberly Heagy

North Carolina State University
Co-authors
CA

Christie Almeyda

North Carolina State University
EV

Emma Volk

University of California
MA

Maher Al Rhawini

University of California Davis
NA
MH

Mark Hoffmann

North Carolina State University
NA
Tuesday September 24, 2024 12:30pm - 12:40pm HST
South Pacific 4

12:30pm HST

WCPM 1/HEMP - Effects of Row-middle Cover Crops on Strawberry Plasticulture Production
Tuesday September 24, 2024 12:30pm - 12:40pm HST
The United States ranks second in strawberry production worldwide. Much of this production has been transitioned from perennial matted row to annual plasticulture production. However, in states like Indiana, growers are exploring a hybrid system: multi-year plasticulture production. In response, we explored cover crops for row-middle weed management in plasticulture strawberry production. In September 2022, we planted ‘Chandler’ strawberry plugs into white polyethylene-mulched rows at Lafayette and Vincennes, IN. We established five row-middle treatments: nontreated and wheat straw mulch controls and three cover crops (oats, cereal rye, and white clover). The oats were winter-killed, and the cereal rye was roller-crimped in mid-May of 2023. Data collected included percent cover crop and weed canopy (per 0.09 m2); frost-killed flowers, live flowers, and developed fruits per plant within 2 weeks after the last spring frost; and total fruit number and yield per plant. At 7 weeks after transplanting (WAP), the oats canopy (82%) was greater than that of cereal rye (61%) and white clover (22%) but less than straw mulch (96%). Weed canopy in the straw mulch and oats was 6%, less than the nontreated control (38%). At 27 and 35 WAP, the cereal rye canopy was 96% and 100%, respectively; while the other treatments had less than 85% and 74% coverage, respectively. At 27 WAP, cereal rye and oats at both sites and straw mulch at Vincennes had less weed canopy (< 7%) than the nontreated control (>63%). At 35 WAP, only cereal rye had no weed canopy. At Lafayette, all treatments had 15 frost-killed flowers per plant. At Vincennes, all treatments had 8 frost-killed flowers per plant, except cereal rye (2 frost-killed flowers per plant). There were no differences among treatments in the live flower count. The number of developed fruits at both sites was significantly greater with cereal rye (8 fruits per plant) compared to all the other treatments (≤ 5 fruit per plant). Total harvested fruit number and yield at Lafayette was 17 fruits per plant and 135 g per plant for all treatments. At Vincennes, cereal rye resulted in significantly greater fruit number (10 fruits per plant) and yield (99 g per plant) compared to all other treatments (≤ 5 fruit and ≤ 49 g per plant). This study demonstrated that cereal rye was the most effective choice for suppressing weeds while maintaining or increasing strawberry yield in the first year of a multi-year plasticulture production system.
Speakers
avatar for Jeanine Arana

Jeanine Arana

Purdue University
Co-authors
SM

Stephen Meyers

Purdue University
WG

Wenjing Guan

Purdue University
Tuesday September 24, 2024 12:30pm - 12:40pm HST
Lehua Suite

12:35pm HST

PH 1/QUAL - Efficacy of Ultraviolet Radiation for Control of the Mucor Rot Pathogen in Post-harvest Anjou and Bartlett Pears
Tuesday September 24, 2024 12:35pm - 12:45pm HST
Mucor rot is caused by the pathogen Mucor piriformis, which can be responsible for severe post-harvest decay in a wide variety of commercially important fruit. There are a minimal number of fungicides that have been shown to be effective against Mucor rot. As a result, alternative methods for control of Mucor rot are currently being investigated. Ultraviolet light in the C spectrum (UV-C) is a germicidal form of radiation that has been demonstrated to kill common post-harvest pathogens. Little information is available for the effectiveness of UV-C light against M. piriformis. For this study, a Far-UV light (222-nm) and a UV-C light (265-nm) were tested for their ability to inactivate M. piriformis. The effects of three UV-C light treatments (0kJ, 10kJ, and 20kJ) were tested on Anjou and Bartlett pears that had been wound inoculated with M. piriformis. Lesion sizes were measured after five weeks in cold storage. The optimal dose required to inactivate M. piriformis in vitro in polystyrene wells with the Far-UV light was found to be 9 kJ, which, with available bulbs set at 8 cm distance, required 17 minutes of treatment. Results showed no significant effect of treatment on final lesion size for both the Far-UV light and the UV-C light. For both lights, final mean lesion sizes were larger for fruit that had been treated with the 20kJ and 10 kJ treatments when compared to the control fruit that received no UV-C treatment. Results from this study suggest that UV-C radiation in the 222-nm and 265-nm light spectrum have minimal impacts on reducing rot caused by M. piriformis in Anjou and Bartlett pears, and, given the duration of treatment required for spore deactivation, this technology may prove impractical for managing M. piriformis on other components of pear packing systems.
Speakers Co-authors
KW

Kevin Wang

USDA-ARS
NA
RL

Rachel Leisso

USDA-ARS Hood River Worksite
Tuesday September 24, 2024 12:35pm - 12:45pm HST
South Pacific 1

12:35pm HST

VCM 1 - Are Locally Sourced Biochar and Poultry Litter the Solution to Improving Soil Health and Sustainably Producing Tomatoes?
Tuesday September 24, 2024 12:35pm - 12:45pm HST
Agriculture is challenged by nutrient runoff, declining soil health, and high costs of inorganic fertilizers. This study investigates the potential of locally sourced biochar and poultry litter to address these issues by enhancing soil health and tomato production. Conducted in Spring 2023, the field trial assessed biochar application rates of 0, 10, 15, and 20 (tons/acre), combined with either organic (poultry litter) or inorganic fertilizer providing (225 N lbs/acre) for the growing period of the tomatoes. Utilizing a randomized complete block design, the experiment had four replications across ten treatments. The findings from this study revealed no significant differences in tomato yield between plants fertilized organically or inorganically across the various biochar application rates. Notably, the use of poultry litter as an organic fertilizer showcased promising results, particularly evident in the increased production of extra-large tomatoes. However, it also led to a higher count of culls. Biochar application significantly enhanced several key soil chemical properties, including pH levels, cation exchange capacity (CEC), and nutrient retention, especially at higher application rates. The incorporation of biochar was observed to substantially elevate soil pH by the season's end, attributed mainly to its considerable calcium content. A biochar application rate of (20 tons/acre) notably increased the pH to 6.8 in the inorganic treatment and even higher to 7.2 in the organic treatment when combined with calcium-rich poultry litter. In scenarios without biochar, the sandy loam soils exhibited a decrease in pH levels by the end of the season, indicating biochar's crucial role in counteracting soil acidification. The study also highlighted that a high biochar application rate significantly improved CEC in both inorganic and organic production systems by the season's end, facilitating better nutrient retention in sandy loam soils. Furthermore, higher biochar applications were associated with lower nitrate concentrations, while the absence of biochar in both treatments led to increased nitrate levels. This pattern was similarly observed with ammonium levels, where higher biochar applications resulted in reduced concentrations, suggesting that biochar effectively prevents the volatilization of ammonia. The research supports the hypothesis that biochar functions like a sponge, retaining essential nutrients within the soil matrix. This study provides evidence that biochar presents a viable strategy for organic and inorganic farmers to enhance soil chemical properties over the long term, offering a sustainable solution to improve agricultural practices and tomato production.
Speakers
ES

Emilio Suarez Romero

University of Georgia
Co-authors
HY

Henry Y Sintim

University of Georgia
NA
JC

Juan Carlos Diaz Perez

University of Georgia
KC

Kate Cassity Duffey

University of Georgia
NA
TM

Ted McAvoy

University of Georgia
NA
Tuesday September 24, 2024 12:35pm - 12:45pm HST
Nautilus 1

12:40pm HST

GG 1 - Enhancing Ornamental Traits through Induced Polyploidy in Hibiscus hamabo: A Cytomolecular Analysis
Tuesday September 24, 2024 12:40pm - 12:50pm HST
The Hibiscus genus, encompassing roughly 300 species across 10 sections, presents a diverse and economically significant range of industrial, ornamental, and medicinal properties. Polyploidy, whether occurring spontaneously or induced through external agents, such as chemicals like colchicine and oryzalin, plays a crucial role in plant breeding. It enhances various attributes including flower size, resilience, and metabolite production. Among the species in this genus, Hibiscus hamabo is noted for its salt tolerance and its attractive yellow flowers in summer and golden-yellow or burnt orange leaves in fall. However, H. hamabo typically has small and sparse flowers, which led to our efforts to enhance its ornamental value through induced polyploidy. In our study, we treated germinating seeds of H. hamabo with three concentrations of colchicine (0, 0.125, and 0.25% v/v) for varying durations (6, 12, or 24 hours). The most effective conversion was achieved with seeds treated with 0.25% v/v colchicine for 24 hours. This treatment produced solid polyploids (4n = 184) and mixed-polyploids (2n 4n). The 4n plants exhibited a 2C-DNA content of 8.50 pg, compared to 4.23 pg in the untreated (2n = 92) plants. We evaluated the impact of induced polyploidy on several morphological traits including leaf color, shape, size, trichome density, and plant height. Significant differences were observed between the polyploid plants and the control plants. Additionally, we explored the cytomolecular analysis of induced polyploidy, particularly focusing on the distribution and organization of rDNA. In 2n plants, one locus of 5S and four loci of 35S rDNA (two major and two minor) were identified. The 5S site is pericentromeric, while one of the major 35S sites is sub-terminal, and the others are at terminal locations. In 4n plants, the number of 5S and 35S sites was exactly duplicated, confirming the polyploidization at the genetic level. Our results proved that colchicine can be used to induce polyploidy in germinating H. hamabo seeds, paving the way for the improvement of this species through this method.
Speakers Co-authors
Tuesday September 24, 2024 12:40pm - 12:50pm HST
South Pacific 2

12:40pm HST

O/LT 1 - Physiological and Morphological Characteristics of Marigold Exposed to Different Ratios of Blue Light and Red Light
Tuesday September 24, 2024 12:40pm - 12:50pm HST
Light plays a crucial role in regulating various aspects of plant growth, development, and metabolism. The absorption spectra of photosynthetic pigments are primarily concentrated in the blue (400-500nm) and red (600-750nm) regions of light, making these wavelengths particularly influential in plant morphogenesis and photosynthesis. Varying the ratios of blue to red light can produce distinct morphological and physiological outcomes in plants. Blue light enhances photosynthetic activity and promotes more compact and robust growth, while red light encourages rapid growth and flowering. These specific combinations can be optimized for desirable traits in ornamental plants. This research aims to evaluate the effects of different combinations of blue and red light on the physiological and morphological characteristics of marigold (Tagetes erecta) ‘Crackerjack’. Seeds were sowed in Metromix 820 potting mix and placed on a misting bench for germination. After germination, seedlings were subjected to three different light spectra: 10% blue and 90% red LEDs (10¬B90R), 25%blue and 75% red LEDs (25B75R), and 50% blue and 50% red LEDs (50B50R) maintained using a spectrometer (StellarNet Inc.). A 90% shade cloth was used in each treatment to prevent the effect of outside light. The photosynthetic photon flux density (PPFD) was maintained at 150 µmol.m-2.s-1 and the photoperiod was maintained at 12 h light and 12 h dark. After four weeks, various physiological and morphological parameters were assessed in five destructively harvested seedlings per treatment. We found that seedlings grown under the 25B75R treatment exhibited greater height in comparison to those under the 50B50R spectrum but similar to seedlings under 10¬B90R. Stomatal conductance (gs) and photochemical efficiency (Fv/Fm) were higher under 50B50R than in 25B75R but comparable to those in 10¬B90R. Additionally, the SPAD and NDVI values, which indicate chlorophyll content and overall plant health, were highest under the 50B50R treatment. However, leaf area, total fresh weight, and total dry weight showed no significant differences among the treatments.
Speakers
AC

Anju Chaudhary

Utah State University
Co-authors
SP

Shital Poudyal

Utah State University
NA
Tuesday September 24, 2024 12:40pm - 12:50pm HST
Kahili

12:40pm HST

POM 1 - Promising Advanced Selections from Kentucky State University’s Pawpaw (Asimina triloba) Breeding Program.
Tuesday September 24, 2024 12:40pm - 12:50pm HST
The North American Pawpaw (Asimina triloba) is a tree fruit native to the Eastern U.S. which is being produced in commercial orchards across the U.S. and internationally, with an increasing market and interest. There are approximately 50 pawpaw cultivars available, but many of these varieties have low yields with fruit sizes below the threshold of 120 grams needed for commercial sale and processing. New high yielding cultivars with excellent fruit quality would further assist in the development of the pawpaw industry. Kentucky State University serves as the National Clonal Germplasm Repository for Pawpaw. Two goals of the Repository research efforts are germplasm acquisition and evaluation. The repository contains over 2000 accessions from 16 different states; additionally, both open pollinated seedlings from superior genotypes and crosses of superior selections have been incorporated into the repository collection. Fruit weights from three of KSU’s advanced selections (Hi 1-4, Hi 7-1, and G6-120) were compared to the cultivars ‘KSU-Atwood’, ‘KSU-Benson’, ‘KSU-Chappell’, ‘Ralph’s Whopper’, and ‘Sunflower’. Fruit weights for Hi 1-4 (241.5 g) and Hi 7-1 (233.5 g) were significantly larger than ‘Sunflower’ (145.3 g). Hi 1-4 and Hi 7-1 show potential to be promising new releases and have been budded onto seedling rootstock for further evaluation.
Speakers
JL

Jeremy Lowe

Kentucky State University
Co-authors
KB

Kirie Broberg

Kentucky State University
NA
KP

Kirk Pomper

Kentucky State University
Dr. Kirk W. Pomper is the Professor of Horticulture in the College of Agriculture, Community, and the Sciences at Kentucky State University in Frankfort, Kentucky. As Horticulture Research Leader, his program is focused on research and Extension efforts toward developing pawpaw as... Read More →
SC

Sheri Crabtree

Kentucky State University
Tuesday September 24, 2024 12:40pm - 12:50pm HST
Coral 2

12:40pm HST

UG 1 - Growth and Volatile Compounds on Thai Herbs at Different Cultivation Systems in Vertical Farming
Tuesday September 24, 2024 12:40pm - 12:50pm HST
Thai culinary herbs such as coriander and sweet basil become popular. For production of them in vertical farming, we need to investigate the suitable growing conditions, especially the relationship between nutrition condition in the root zone and vegetation growth. Moreover, we investigated the aroma quality under these conditions. Here, we report the comparing of nutrient conditions at both of perlite and hydroponic cultivation. Thai coriander (Coriandrum sativum ‘Saisamorn’) and Thai sweet basil seeds (Ocimum basilicum ‘Micro’) were sown under white LEDs for 24 hr. After 14 days, seedlings were transplanted into deep flow hydroponic culture in environment-controlled growth chamber at air temperature of 25℃, 60% relative humidity, and luminance at PPFD 450 µmol/m/s. The photoperiod was set for 16 hr. light and 8 hr. dark. Different concentrations ranged from EC 1.6, 2.0, and 3.5 at pH 5-6 of nutrient solution were supplied to hydroponic system and perlite system. The perlite system was used by mixing vermiculite with perlite at ratio of 1:2. The mixture of vermiculite and perlite was poured into planter for herb cultivation. Dripping tubes were provide for irrigation. After 40-50 days of transplant, vegetative growth; fresh weight, shoot growth, root length, and stem growth were measured. The major aromatic compounds for coriander such as Decanal, Dodecanal, (Z)-3-hexenol, (Z)-3-hexenyl acetate, and trans-2-dodecenal, and major aromatic compounds for sweet basil such as linalool, eugenol, methyl eugenol, estragole, eucalyptol were evaluated by using GC-MS. The growth and volatile compounds of coriander and sweet basil are varied toward nutrient solution condition and cultivation systems. As the result of this study, it can be assumed that we have found one of the optimum conditions to cultivate Thai herbs in a controlled environment.
Speakers
AS

Akira Sakai

Meiji University
Co-authors
JS

Junjira Satitmunnaithum

Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University , Japan
TI

Takashi Ikeda

School of Agriculture, Meiji university
NA
Tuesday September 24, 2024 12:40pm - 12:50pm HST
South Pacific 3

12:40pm HST

VSF 1 - Learning Sustainable Edible Gardening through Hands-on Approach with Muscadine Grapes
Tuesday September 24, 2024 12:40pm - 12:50pm HST
As the growing number of individuals moving to Florida has increased to over 1000 residents on average per day. Also, with the current focus on Florida’s water conservation
Speakers
CJ

Claude Judith Jean

University of Florida
Co-authors
BC

Brittany Council-Morton

University of Florida
JP

Julio Perez

University of Florida
NA
TF

Terra Freeman

UF/IFAS Extension St. Johns County
Tuesday September 24, 2024 12:40pm - 12:50pm HST
South Pacific 4
  Poster presentation (individual talk), Viticulture and Small Fruits 1
  • SUBJECT Viticulture
  • quality, alternative crops are a 15) and the second in March 2024 (n=19). Within both two-hour workshops, participants were able to go home with a muscadine grape cultivar of their choosing. The first workshop covered pest management, cultivar selection, and culture. Participants harvested and sampled fruit from different cultivars and then made cuttings of different varieties to propagate their own. The second workshop focused on the maintenance of grape vines. From the first workshop’s exit survey, participants reported intending on make changes to their landscape practices, including Right Plant Right Place (87%), Fertilize Appropriately (93%), Water Efficiently (67%), and Mulching (73%). 100% of participants also reported willingness to attempt to grow muscadines in the home landscape. From the second workshop, Right Plant Right Place (61%), Fertilize Appropriately (67%), Water Efficiently (44%), and Mulching (55%). 94% of participants self-reported that they felt better in managing muscadine vines, including installation

12:40pm HST

WCPM 1/HEMP - Palmer Amaranth and Waterhemp in the Pacific Northwest: Glyphosate Resistance Confirmation and Implications for Crop Production
Tuesday September 24, 2024 12:40pm - 12:50pm HST
Palmer amaranth (Amaranthus palmeri) and waterhemp (Amaranthus tuberculatus) are the two most troublesome pigweeds in crop production systems in the United States. These pigweeds just started to appear in the Pacific Northwest (PNW). A coordinated extension and outreach effort among land-grant universities (University of Idaho and Oregon State University), Amalgamated Sugar, other commodity commissions, and industry was launched to track Palmer amaranth and waterhemp in the PNW. In 2023, tissue samples were collected from pigweeds suspected to be Palmer amaranth and waterhemp and sent to Colorado State University for KASP genotyping test to confirm if the species were Palmer amaranth and waterhemp. The KASP test confirmed that the suspected pigweeds were Palmer amaranth and waterhemp. Since the majority of these pigweeds survived multiple applications of glyphosate, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene duplication analysis was conducted to confirm possible glyphosate resistance in the Palmer amaranth and waterhemp populations. About 70% (17 out of 23) of the Palmer amaranth tissue samples showed gene duplication of up to 184 EPSPS gene copies, indicative of glyphosate resistance. All three populations of waterhemp showed gene duplication of 5.7 to 9.2 EPSPS gene copies indicative of glyphosate resistance. The widespread glyphosate resistance in the samples collected suggests that Palmer amaranth and waterhemp being introduced into the PNW are coming from States where these weeds have developed resistance to multiple herbicide groups. This would have huge implications for weed control in vegetables and other crops in the PNW.
Speakers
AA

Albert Adjesiwor

University of Idaho
Co-authors
AS

Andre Simoes Araujo

Colorado State University
NA
CA

Clarke Alder

Amalgamated Sugar
NA
JF

Joel Felix

Oregon State University
NA
TG

Todd Gaines

Colorado State University
NA
Tuesday September 24, 2024 12:40pm - 12:50pm HST
Lehua Suite

12:40pm HST

Exhibitor Talk: Apogee Instruments
Tuesday September 24, 2024 12:40pm - 12:55pm HST
Tuesday September 24, 2024 12:40pm - 12:55pm HST
Coral 5

12:45pm HST

PH 1/QUAL - Preliminary Insights Into the Effects of Various Technologies of 1-methylcyclopropene (1-MCP) “AnsiP®” on Apple Fruit Quality During Shelf Life
Tuesday September 24, 2024 12:45pm - 12:55pm HST
Various postharvest formulations of 1-MCP have been innovated to optimize its efficacy for repeated use across storage, transportation, and retail stages. For small farms or fruits destined for farmers' markets, utilizing postharvest technologies with minimal 1-MCP concentrations is pivotal. In this trial, fruit from ‘Empire’, ‘Red Delicious’, and ‘RubyFrost’ apples was obtained from Cornell orchards in Lansing NY and Cornell AgriTech orchards in Geneva NY, on October 1, 4, and 13, respectively. Fruit were transported to the postharvest laboratory at Cornell University in Ithaca NY and fruit maturity indices were assessed. After cooling the fruit overnight, three different formulations of 1-MCP (tablet - AnsiP®-G, sticker - AnsiP®-Sticker, and sheet - AnsiP®-S, LYTONE Enterprise, Inc., Taiwan) were tested. The treatments were applied to fruit packed in cardboard boxes (30×30×48 cm), each containing 4 trays, at 3 °C for 24 hours. Fruit were then transferred to 20 ⁰C for 4 weeks, and fruit quality including internal ethylene concentration (IEC), flesh firmness, soluble solid content, titratable acidity, fruit color, IAD value index for peel chlorophyll content, and fruit weight were assessed weekly. Additionally, the release dynamics of 1-MCP from tablets, stickers, and sheets were evaluated in different trial. The 1-MCP tablets outperformed other treatments in reducing IEC and maintaining fruit firmness. The effects of different 1-MCP technologies on apple fruit quality and longevity during shelf life will be discussed.
Speakers
YA

Yosef Al Shoffe

Cornell Univeristy
Tuesday September 24, 2024 12:45pm - 12:55pm HST
South Pacific 1

12:45pm HST

VCM 1 - Is Trellising Beneficial to High Tunnel Melon Yield?
Tuesday September 24, 2024 12:45pm - 12:55pm HST
Cantaloupes (Cucumis melo var. reticulatis) are a fruiting vegetable which grow best in warm environments. Cantaloupes also are infected by many foliar diseases which are triggered or exacerbated by rainfall and high relative humidity which is common during the growing season in Central Appalachia. One potential option for growing cantaloupes in West Virginia is high tunnel production. High tunnels significantly increase the air and soil temperature. In addition, the crop can be drip irrigated so there is no wet foliage for disease infection. Trellising may be necessary to facilitate harvest. Vertical trellising with pruning may be necessary for high tunnel production. Trellising can potentially increase marketable yield. However, trellis and pruning labor can be as high as $150/1000 ft2. Cantaloupes (cv. ‘Sugar Cube’) were transplanted within a high tunnel in 2023 and 2024. Vertical trellising and pruning were compared with non-trellised and non-pruned plants. Inputs such as labor and trellising supplies were recorded. In 2023, trellising did not significantly increase marketable yield of cantaloupes, but did significantly improve harvest efficiency.
Speakers
Tuesday September 24, 2024 12:45pm - 12:55pm HST
Nautilus 1

12:50pm HST

GG 1 - Insights into the Genetic Diversity and Population Structure of Wild and Cultivated Spinach
Tuesday September 24, 2024 12:50pm - 1:00pm HST
The wealth of genetic and phenotypic diversity in plant species serves as the primary source of novel traits in plant breeding and crop improvement efforts. Spinach (Spinacia oleracea) has a long cultivation history across diverse environments and geographic regions, which has resulted in adaptation to diverse conditions. This adaptation has been influenced further by human preferences for distinct leaf shapes, tastes, flavors, and nutrition, constituting a rich reserve of genetic and phenotypic diversity within Spinacia germplasm. Moreover, wild species (S. tetrandra and S. turkestanica) offer valuable resources, particularly for traits of commercial significance, such as resistance to prevalent pathogens and pests. Therefore, understanding the genetic variations that underlie phenotypic traits is crucial to enable effective gene introgression and the development of novel spinach varieties. We recently investigated the genetic diversity and population structure of a panel of over 500 cultivated and wild germplasm obtained from the Centre for Genetic Resources, the Netherlands (CGN) at Wageningen University and Research (WUR). This panel, complemented with material from other sources, comprised 49 S. tetrandra and 86 S. turkestanica accessions. Our findings revealed the presence of significant genetic diversity within these panels of accessions, which were categorized into multiple distinct population groups. We evaluate this Spinacia panel for several horticulturally important traits to identify SNP markers and candidate gene regions associated with commercially important traits. Our objectives are to share novel insights into the genetic diversity of spinach and provide valuable molecular markers for improving cultivated spinach production.
Speakers
GB

Gehendra Bhattarai

University of Arkansas
Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
CK

Chris Kik

Centre for Genetic Resources, the Netherlands (CGN), Wageningen University and Research
NA
LD

Lindsey du Toit

Mount Vernon Northwestern Washington Research and Extension Center, Washington State University
NA
RV

Rob van Treuren

Centre for Genetic Resources, the Netherlands (CGN), Wageningen University and Research
NA
SG

Sanjaya Gyawali

Sakata Seed America Inc.
NA
Tuesday September 24, 2024 12:50pm - 1:00pm HST
South Pacific 2

12:50pm HST

O/LT 1 - Responses of Calamagrostis ×acutiflora under Deficit Irrigation
Tuesday September 24, 2024 12:50pm - 1:00pm HST
Deficit irrigation plays a crucial role in water conservation in urban landscapes. Calamagrostis ×acutiflora (feather reed grass) is an ornamental grass known for its neat clumps, golden plumes, and fast growth. It is gaining popularity in urban landscapes across arid and semi-arid regions in the United States. However, little is known about its responses to deficit irrigation. A field study was conducted in 2022 and 2023 at the Utah Agricultural Experiment Station’s Greenville Research Farm in North Logan, UT, to assess the effect of irrigation frequencies on the growth of feather reed grass. Reference evapotranspiration (ETo) data from a weather station in the Utah AgWeather System, Utah Climate Center, Logan, UT, was used to determine the irrigation frequency for each treatment. Four hundred plants were transplanted into the field plot, with twenty plants in each of the twenty 2 by 2-meter plots. Eighty plants within four plots were randomly assigned to one of five irrigation treatments, controlled based on 80%, 60%, 40%, 20%, and 0% ETo. Two harvests were conducted on 30 Sep 2022 and 3 Nov 2023, during which plant height, number of tillers, and biomass were recorded. Plants height, number of tillers, and biomass for both years exhibited a linear and quadratic increase as the irrigation frequencies increased from 0% to 80% ETo. In addition, the linear relationship between irrigation treatments and grass height became less distinct in 2023, although grasses irrigated at 80% ETo were taller compared with those at lower irrigation levels. Based on the results, an irrigation frequency of 40% to 60% ETo is recommended for feather reed grass to maintain optimal growth.
Speakers
ZW

Zirui Wang

Utah State University
Co-authors
JJ

Ji Jhong Chen

Utah State University
NA
YS

Youping Sun

Utah State University
Tuesday September 24, 2024 12:50pm - 1:00pm HST
Kahili

12:50pm HST

POM 1 - Assessment of Fruit Quality and Value-added Potential of 16 Pawpaw Cultivars and Advanced Selections
Tuesday September 24, 2024 12:50pm - 1:00pm HST
The North American pawpaw [Asimina triloba (L.) Dunal] is a native tree-fruit that is in the early stages of commercial production in the United States. Pawpaw fruit have fresh market appeal for farmers markets, community supported agriculture, and organic markets, as well as processing potential for frozen pulp production. For the processing market, fruit with a large size of over 120 grams and less than 6 percent seed by weight, are desirable for processing for pulp recovery for value-added products such as hot sauce. Kentucky State University has already released three pawpaw cultivars, KSU-AtwoodTM in 2009, KSU-BensonTM in 2016, and KSU-ChappellTM in 2018. However, new high yielding cultivars with excellent fruit quality would further assist in the development of the pawpaw industry. The objective of this study was to determine the fruit quality of 16 pawpaw cultivars and advanced selections. Fruit weight, percent seed, and brix were determined for the cultivars and advanced selections grown at the Kentucky State University Research and Demonstration Farm in Frankfort, Kentucky. The cultivars and advanced selections evaluated were A3-1, A6-1, KSU-AtwoodTM, KSU-BensonTM, KSU-ChappellTM, G4-25, G6-120, G9-109, Hi 1-4, Hi 7-1, Hy3-120, NRVT 3-10, NRVT 3-4, Sunflower, Susquehanna, and Tallahatchie. Average fruit weight ranged from Tallahatchie at 138g to A-6-1 at 277g per fruit. A number of advanced selections had large fruit size and these included A6-1 (277g), Hy3-120 (258g), A3-1 (216g), Hi1-4 (214g), NRVT3-4 (208g), Hi7-1 (202g) and G9-109 (201g). Average percent seed for fruit ranged from G6-120 at 8.2 percent seed to the cultivar KSU-ChappellTM at 4.5 percent seed. A number of advanced selections had low percent seed and these included A6-1 (4.7%) and G4-25 (5.8%). Average percent Brix for fruit ranged from NRVT 3-10 at 19.8 Brix to the cultivar KSU-ChappellTM at 28.2 Brix. Many of these advanced selections show promise as potential new cultivars. Examples of hot sauce made from pawpaw pulp extracted from cultivars will be discussed.
Speakers
KP

Kirk Pomper

Dean College of Agriculture, Kentucky State University
Co-authors
JL

Jeremy Lowe

Kentucky State University
KB

Kirie Broberg

Kentucky State University
NA
MB

Matthew Behrends

Kentucky State University
SC

Sheri Crabtree

Kentucky State University
Tuesday September 24, 2024 12:50pm - 1:00pm HST
Coral 2

12:50pm HST

UG 1 - Growth, Anthocyanin Content and Its Gene Expression in Purple Color Paprika Fruit Applying Blue Light at Night
Tuesday September 24, 2024 12:50pm - 1:00pm HST
In this study, we investigated the effect of night blue lighting on anthocyanin content and expression of its transcription factors and structural genes in purple paprika fruits. Purple paprika fruits (Capsicum annuum L. ‘Tequila’) were used for this experiment. Before light treatment, we used fifty plants grown under hydroponic conditions (EC 2.5, pH 6.0) in a greenhouse. At 10 days after pollination, we started irradiating the fruits at night with blue LEDs light at wavelength 460 nm and radiation intensity at 500 W-m-2. Control is non-irradiated treatment. Fruits were harvested at 15, 20, and 40 days after pollination, for fresh weight evaluation, then following analysis was performed. In the pigment analysis, anthocyanin content was determined based on cyanidin-3-glucoside. By adding 10% acetic acid to frozen ground fruit sample overnight at 4C, the absorbance was measured at 530 nm. In the gene analysis, RNA was extracted from fruit and cDNA was transcripted using kit with gDNA eraser. Then, cDNA template was mixed with PCR Master Mix for quantitative RT PCR analysis. The result was calculated as relative expression to UBI. As the results, fresh weight was not affected by light. Anthocyanin content of treated fruit increased approximately twice as much as that of control fruits at 15, 20, and 40 days after pollination. Furthermore, the expression levels of transcription factors; HY5, MYB, bHLH, and WDR, and structural genes; PAL, CHS, F3H, ANS, DFR, and UFGT increased in treated fruits. These results indicate that blue light irradiation enhanced anthocyanin synthesis in purple paprika fruits, by increasing the expression of its transcription factors and structural genes.
Speakers
RM

Ryuhei Mitsuzuka

Meiji University
Co-authors
IA

Itsuki Abe

School of Agriculture, Meiji University,
NA
JS

Junjira Satitmunnaithum

Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University , Japan
TI

Takashi Ikeda

School of Agriculture, Meiji University
NA
Tuesday September 24, 2024 12:50pm - 1:00pm HST
South Pacific 3

12:50pm HST

VSF 1 - Creating a Practical Approach for Wine Grape Grower to Predict Grapevine Water Status by Precision Viticulture Technologies
Tuesday September 24, 2024 12:50pm - 1:00pm HST
With the water regulations getting stricter in California and the climatic conditions getting warmer and drier during grape growing seasons, grape growers are forced to improve irrigation efficiency and eventually conserve water usage. This study was designed to incorporate soil moisture sensors and local above-ground weather stations to estimate grapevine water status with the goal to potentially replace pressure chamber measurement, which is the most popular plant-based method of measuring grapevine water status but labor-intensive and time-consuming. The study was conducted in a Barbera vineyard in Fresno, CA and there were four different regimes used in this study, including 50%, 75%, 100% crop evapotranspiration (ETc) replacement, and an over-irrigated condition (>150% ETc). Three Sony’s soil moisture sensors were installed at 20cm, 37.5 cm, and 75 cm in the soil paired with four time-domain reflectometry (TDR) sensors at 20cm, 37.5cm, 75cm, and 150cm in the soil to continuously monitor additional soil conditions besides soil moisture content. The above-ground weather conditions were collected from a nearby California Irrigation Management Information System (CIMIS) station (
Speakers
RY

Runze Yu

Assistant Professor, California State University, Fresno
Co-authors
GS

Gen Sakoda

Sony Semiconductor Solutions Corporation
NA
SN

Seiya Nishimura

Sony Semiconductor Solutions Corporation
NA
SM

Sho Murakoshi

Sony Semiconductor Solutions Corporation
NA
TT

Takashi Takinami

Sony Semiconductor Solutions Corporation
NA
Tuesday September 24, 2024 12:50pm - 1:00pm HST
South Pacific 4

12:50pm HST

WCPM 1/HEMP - Mesotrione and Simazine-Based Tank-Mixes for Late-Season Control of Doveweed in Bermudagrass Turf
Tuesday September 24, 2024 12:50pm - 1:00pm HST
In recent years, doveweed [Murdannia nudiflora (L.) Brenan] has become a pressing concern in Florida and nearby regions due to its rapid expansion and challenging eradication. Despite being considered a warm-season annual broadleaf, its grass-like foliage often enables it going unnoticed within the canopy, especially at early growth stages. Such camouflage allows for quick proliferation and rapid invasion leading to dense mats outcompeting desired turfgrass sward. Limited reliable herbicides exist, and their efficacy declines once the plants get established. Hence, there is a demand for options capable of controlling mature populations. This study assessed the efficacy of mesotrione at 0.37 L ha-1 or 0.58 L ha-1, simazine at 1.10 L ha-1 or 1.83 L ha-1, and their combinations for the late-season control of established doveweed in bermudagrass ‘CR-01’ maintained as a golf course fairway or athletic field at West Florida Research and Education Center in Jay, FL. When used independently, mesotrione alone provided inconsistent control, never surpassing 50%, whereas simazine alone yielded a maximum control of 80%) was achieved within 2 to 6 weeks after the initial treatment, contingent upon the rate, with higher rates yielding a more rapid response. Moreover, the control remained persistent until the conclusion of the study. Severe phytotoxicity was evident in all mesotrione-containing treatments, yet the turf recovered to acceptable levels within 4 weeks following each application.
Speakers
PP

Pawel Petelewicz

University of Florida
Co-authors
AB

Agustin Boeri

Texas A
NA
BU

Bryan Unruh

University of Florida
NA
CM

Chase McKeithen

University of Florida
NA
JG

Jayson Ging

University of Florida
NA
KG

Katarzyna Gawron

University of Florida
NA
Tuesday September 24, 2024 12:50pm - 1:00pm HST
Lehua Suite

12:55pm HST

PH 1/QUAL - Pre-Storage Ambient Temperature Delay Reduces Lenticel Blotch by Mediating Metabolic Alteration in Cold-Stored ‘Summer Prince’ Apples
Tuesday September 24, 2024 12:55pm - 1:05pm HST
Lenticel blotch as peel physiological disorder occurs in cold-stored apple fruit, characterized by irregular shape breakdown tissue without extending to the flesh. This study aimed to evaluate the postharvest treatment effects on fruit quality attributes, mineral nutrients, targeted metabolites, and incidence of lenticel blotch, and their relationship in cold stored ‘Summer Prince’ apple fruit. Fruits were harvested from 2 orchards, treated with postharvest 1-MCP, pre-storage ambient temperature delay for 7 days (ATC), and 1-MCP ATC at harvest and then stored at 0.5 °C for 5 months. There were significant differences in the organic matter content, nitrate nitrogen (NO3-N), and phosphoric acid contents in the soil. Calcium, manganese, copper, and zinc in leaf tissues were significantly different between 2 orchards. Lenticel blotch was effectively controlled by ATC treatment, while exacerbated by 1-MCP. Based on the results of VIP scores, histidine, valine, sucrose, K/Ca ratio, (K Mg P)/Ca ratio, total phenolic compounds, total flavonoids, ABTS, and DPPH were influenced by the postharvest treatments. In the results of volcano plot analysis, ATC treatment effectively controlled the symptoms and up-regulated in amino acids, such as valine, histidine, proline, and isoleucine. However, 1-MCP treatment caused to induce lenticel blotch by upregulating aspartic acid and glutamic acid. Therefore, the results indicated that pre-storage ambient temperature delay should control the lenticel blotch by mediating targeted metabolic alteration during cold storage.
Speakers
HP

Hyowon Park

Chung-Ang University
Co-authors
HP

Hnin Phyu Lwin

Washington State University
JK

Jeonghee Kim

National Institute of Horticultural and Herbal Science
NA
JL

Jinhee Lee

Chung-Ang University
NA
JL

Jinwook Lee

Chung-Ang University
NA
JP

Jongtaek Park

National Institute of Horticultural and Herbal Science
NA
SY

Seung Yeon Han

Chung-Ang University
NA
SK

Soon-il Kwon

National Institute of Horticultural and Herbal Science
NA
Tuesday September 24, 2024 12:55pm - 1:05pm HST
South Pacific 1

12:55pm HST

VCM 1 - Interseeded Clover Does Not Impact Pumpkin Yield
Tuesday September 24, 2024 12:55pm - 1:05pm HST
Pumpkins are usually grown using wide row spacing, and in Minnesota, the canopy does not close until mid-summer and the canopy senesces in early- to mid-autumn. This provides opportunity for establishing frost-tolerant or winter-hardy cover crops between rows before the canopy closes, which will continue to grow after pumpkin foliage is gone. To understand more about competition between interseeded cover crops and pumpkins, four species of clover (berseem, crimson, Persian, and red) were sown between pumpkin rows (10-ft spacing) in late June, and pumpkin yield and clover growth and N content were measured in the fall. Both ‘Cotton Candy’ and ‘Kratos’ pumpkins were studied. ‘Kratos’ yield (68.4 Mg / ha; 1185 fruit / ha), fruit size (9.7 kg), and fruit size variability (28%) were 1.8 times, 0.55 times, 3.2 times, and 1.1 times as much as ‘Cotton Candy’, but none of these responses were impacted by clover. Above-ground biomass of berseem, Persian, and red clovers averaged 0.41 Mg / ha in late fall (16 kg N / ha), but crimson clover yielded 1.2 Mg / ha (33.3 kg N / ha). Clover grown with ‘Kratos’ yielded 69% of the dry matter and 73% of the aboveground nitrogen (per ha) compared to clover grown with ‘Cotton Candy’. The average C:N ratio of all treatments was 18.3. These results show that clover interseeded into pumpkins, especially crimson clover, can grow successfully without impact on pumpkins. High-vigor pumpkins can reduce clover yield, however.
Speakers
avatar for Charlie Rohwer

Charlie Rohwer

Scientist, University of Minnesota
Tuesday September 24, 2024 12:55pm - 1:05pm HST
Nautilus 1

1:00pm HST

GG 1 - Population Analysis of Wild-type Venezuelan Sabadilla
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Schoenocaulon officinale, also known by the common name of sabadilla, is a species of plant belonging to the family Liliaceae. It is thought to be endemic to Mexico; at some point in history, it was spread throughout other parts of South America. Sabadilla is a geophytic perennial bulb plant that is not frost tolerant. Due to the environmental factors where sabadilla grows, it is also hypothesized to be a heliophyte. It is estimated to live, while continuously flowering, for up to 8 years. Sabadilla will normally reach its mature stage at around year 2-3. The seeds of sabadilla contain two insecticidally active chemical compounds known as veratridine and cevadine. The normal compositional range that these compounds make up in the seeds is anywhere from 0.5-5%. The mode of action is similar to that of pyrethrins; these compounds will attach to sodium channels on the insects and cause continuous overactivation until the insect is knocked. It is not yet known which specific sodium channel these compounds act on. Sabadilla has been used by people for thousands of years for its insecticidal properties and alleged homeopathic benefits. However, sabadilla is a relatively untouched and unstudied plant. Due to this, almost no biological, physiological, or genetic work has been done on the plant. The purpose of this research was to delve deeper into population differences of plants that were collected from different environments in Venezuela. In 2019, seeds were collected from 7 distinct geographic locations in Venezuela. They were collected from two different sites (The Ávila National Park
Speakers
Tuesday September 24, 2024 1:00pm - 1:10pm HST
South Pacific 2

1:00pm HST

O/LT 1 - Field Performance of Penstemon Species under Deficit Irrigation
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Water-efficient landscaping can reduce water consumption without compromising the aesthetical appearance of urban landscapes. Penstemon, with more than 250 species available in a spectrum of colors, is a popular choice in xeriscape designs and water-wise gardening due to its ability to thrive in dry conditions while providing attractive visual appeal. However, limited field trials have explored the responses of penstemon under deficit irrigation. This study, conducted at the Utah Agricultural Experiment Station’s Greenville Research Farm, North Logan, UT, USA, from 30 Jun to 31 Oct 2023, was to investigate the overall appearance and canopy temperature responses of three penstemon species: Penstemon barbatus (Cav.) Roth ‘Novapenblu’ (Rock CandyTM blue penstemon), Penstemon pinifolius (pineleaf beardtongue), and Penstemon strictus (rocky mountain beardtongue), under three irrigation frequencies. Reference evapotranspiration (ETo) was utilized to control irrigation frequencies. Eight plants of each penstemon species were randomly assigned to one of three deficit irrigation treatments, calculated based on 80% ETo (high), 50% ETo (moderate), and 20% ETo (low). A monthly evaluation of overall appearance was conducted. Top-view infrared images of plant canopies, from which canopy temperature can be calculated, were captured using a thermal camera. Results revealed that higher irrigation frequency led to better overall appearance, with some variability observed among species and months. Moreover, increased irrigation frequency correlated with lower canopy temperatures, displaying species-specific responses. Further observation is needed to compare the responses of P. strictus, P. pinifolius, and P. barbatus under field conditions.
Speakers
ZW

Zirui Wang

Utah State University
Co-authors
YS

Youping Sun

Utah State University
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Kahili

1:00pm HST

POM 1 - Effects of Temperature and Light on Sunburn, and Preventing the Sunburn Damage by Chemical Suppressants in ‘Fuyu’ Sweet Persimmons
Tuesday September 24, 2024 1:00pm - 1:10pm HST
As global warming progresses, sunburn damage in fruit production is becoming increasingly prevalent. However, there has not been much research on the patterns of sunburn occurrence and effective prevention measures for ‘Fuyu’ sweet persimmons. This pilot study explored the impact of strong light and high temperatures on sunburn occurrence in ‘Fuyu’ sweet persimmons, characterized the temporal pattern of sunburn development, and evaluated the efficacy of chemical suppressants in reducing damage. ‘Fuyu’ persimmons were harvested from an orchard in Jinju-si, Gyeongsangnam-do, South Korea, at 60 days (weak light intensity (WLI) conditions), 72 days (strong light intensity I (SLI-I) conditions), and 79 days (strong light intensity II (SLI-II) conditions) after full bloom. The harvested fruits were divided into five treatment groups: control (Distilled water), 2% Cellulose Nano Crystals (CNCs), 2% Sodium Alginate 300mM CaCl2 (AG), 6% Kaolin 0.1% Tween20 (K), and 2% Vapor Gard® (VG, transpiration inhibitor). Thermocouples were attached to each fruit to measure fruit surface temperature (FST) under the following conditions: WLI (using a chamber set to 200 µmol/m²/s light intensity) and SLI-I, -II (direct sunlight and temperature) conditions. When exposed to WLI conditions, the increase in fruit surface temperatures (FST) compared to air temperatures (AT) was minimal, and no sunburn was observed. Conversely, non-acclimated fruits exposed to SLI-I displayed extensive sunburn damage within a day. However, acclimated fruits under SLI-II revealed differences in sunburn. The kaolin treatment, which exhibited the lowest browning, also showed a significant reduction in FST. However, the carotenoid content was lower in the kaolin treatment compared to the control. To confirm the findings from controlled experiments, field trials were conducted for two years to evaluate the effectiveness of sunburn suppressants. In the first year, kaolin treatment reduced the severity of sunburn by half compared to other chemical suppressants. In the second year, 6% kaolin and a mixture of kaolin and carnauba wax were applied. Both kaolin and a kaolin-carnauba wax mixture effectively reduced sunburn to 30% of the control. These effective treatments decreased FST by up to 3.5℃, maintained high chlorophyll content, and augmented antioxidant enzyme activities. In conclusion, the kaolin treatment combined with carnauba wax was identified as the most promising material for preventing sunburn damage in ‘Fuyu’ persimmons under these environmental circumstances.
Speakers
YS

YUNJI SHIN

Gyeongsang National University
NA
Co-authors
HS

HYUNSUK SHIN

Gyeongsang National University
PM

PANDIYAN MUTHURAMALINGAM

Gyeongsang National University
NA
YP

YEONJU PARK

Gyeongsang National University
NA
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Coral 2

1:00pm HST

UG 1 - The Effect of Mixing Artificial Seawater into Hydroponic Solution to Tomato Fruit Growth and Ion Contents
Tuesday September 24, 2024 1:00pm - 1:10pm HST
NaCl has been frequently used for applying salt stress to plants. However, in this study, we tested to use sea salt instead of NaCl for applying salt stress to tomato plants. Plants were grown under hydroponic conditions, mixing artificial seawater to nutrient solution (liquid fertilizer). To estimate strength of the stress treatment, we used EC (Electrical Conductivity) value to control it. Fifty-six seedings of two tomato varieties ('Momotaro York' and 'Saturn') were grown at deep flow technique in a greenhouse, and the stress treatments were applied 10 days after the first truss bloomed. In experiment 1, we designed 3 treatments (EC was set for 5.0, but the ratio of Liquid Fertilizer : Artificial Seawater were 5.0 : 0, 1.5 : 3.5 and 2.5 : 2.5, respectively). In experiment 2, we designed 3 treatments (EC for liquid fertilizer was set at 1.5, but the concentration of artificial seawater was different as Liquid Fertilizer : Artificial Seawater were 1.5 : 0, 1.5 : 3.0 and 1.5 : 6.0, respectively). Fruits were harvested at almost 90 days after blooming and fruit weights were measured. The contents of 5 cations and 3 anions in fruit were analyzed by high-performance liquid chromatography (HPLC), then we added all of the ions contents as total ion contents. As a result, fruit weight was not different significantly at experiment 1, but decreased when EC value was increased at experiment 2. In experiment 1, when the ratio for liquid fertilizer was increased, the total ion contents were increased, especially Na in treatment at (1.5 : 3.5) and Ca2 in treatment at (5.0 : 0) were increased. At experiment 2, total ion contents increased when the ratio of sea salt was increased. In conclusion, we estimated various strength of stress by EC value in this study. Then the different ratio of liquid fertilizer and artificial seawater caused different ion contents in tomato fruits. This result was similar for the two varieties.
Speakers
MB

Miyuki Baba

Meiji University
Co-authors
RE

Riko Endo

School of Agriculture, Meiji University
NA
TI

Takashi Ikeda

School of Agriculture, Meiji University
NA
Tuesday September 24, 2024 1:00pm - 1:10pm HST
South Pacific 3

1:00pm HST

VSF 1 - Effect of Planting Distance on PD Resistant Predominantly Vitis Vinifera Grape ‘502-20’ During the Years of Establishment
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Presently, Vitis vinifera grape production in Alabama and the southeastern U.S. is extremely limited due to Pierce’s disease (PD), caused by the bacterium Xylella fastidiosa (Xf) and vectored by insects from the family Cicadellidae. In 2019, UC Davis grape breeding program has released five PD resistant predominantly V. vinifera cultivars which can help sustain the vinifera grape cultivation in the region. Although these new cultivars are currently available, no V. vinifera grape production and management recommendations exist for Alabama conditions. An experimental vineyard was planted at the Chilton Research Extension Center, AL in 2017 to determine the effect of planting distance on vegetative growth and productivity of PD resistant, predominantly V. vinifera advanced selection ‘502-20’. The experiment utilizes a randomized complete block design consisting of three blocks with three vines per block. Vines were planted at an in-row distances of 1.8m, 2.1m and 2.4m and a between row distance of 3.7m and trained to a Watson system. Vine phenology, vegetative growth, yield, and fruit quality characteristics data were recorded during the period of vine establishment (2019-2023). Our results suggest there was a significant treatment by year interaction effect on pruning weight with the lowest pruning weight of 0.8 kg/vine found for vines at an in-row spacing of 2.1m during 2021. Treatment by year interaction also resulted in the highest yield per vine (28.0 kg/vine) measured for vines planted at 2.4m in 2021. Planting distance of 2.4m resulted in a significant increase of the number of clusters per vine during 2021 and 2022 seasons, while no vine spacing effect was found to account for differences in cluster weight, berry mass, or total soluble solids (TSS). Current results indicate planting distance of 2.4m x 3.7m can increase the yield of ‘502-20’ during the years of vine establishment and contribute to sustainable production of PD resistant predominantly V. vinifera grapes in Alabama conditions. Further research will be conducted to expand current knowledge and assist in the development of management recommendations for the successful production of V. vinifera grapes in the region.
Speakers
EC

Elina Coneva

Auburn University
Co-authors
BC

Bernardo Chaves-Cordoba

Auburn University
NA
EV

Edgar Vinson

Auburn University
NA
MR

Melba Ruth Salazar Gutierrez

Auburn University
NA
SR

Sushan Ru

Auburn University
Tuesday September 24, 2024 1:00pm - 1:10pm HST
South Pacific 4

1:00pm HST

WCPM 1/HEMP- Simulation-Based Nozzle Density Optimization for Maximized Efficacy of a Machine-Vision Weed Control System for Applications in Turfgrass Settings
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Targeted spray application technologies have the capacity to drastically reduce herbicide inputs but to be successful, performance of both machine vision (MV) based weed detection and actuator efficiency need to be optimized. This study assessed 1) the performance of spotted spurge recognition in ‘Latitude 36’ bermudagrass turf canopy using the You Only Look Once (YOLOv3) real-time multi-object detection algorithm, and 2) the impact of various nozzle densities on model efficiency and projected herbicide reduction under simulated conditions. The YOLOv3 model was trained and validated with a dataset of 1,191 images. The simulation design consisted of 4 grid matrix regimes (3 × 3, 6 × 6, 12 × 12, and 24 × 24) which would then correspond to 3, 6, 12, and 24 non-overlapping nozzles, respectively; covering a 50-cm wide band. Simulated efficiency testing was conducted using 50 images containing predictions (labels) generated with the trained YOLO model and, by applying each of the grid matrixes to individual images. The model resulted in prediction accuracy of a F1 Score of 0.62 precision of 0.65 and recall value of 0.60. Increased nozzle density (from 3 to 12) improved actuator precision and predicted herbicide-use efficiency with a reduction in false hits ratio from ~30% to 5%. The area required to ensure herbicide deposition to all spotted spurge detected within images was reduced to 18% resulting in ~80% herbicide savings compared to broadcast application. Slightly greater precision was predicted with 24 nozzles, but not statistically different from the 12-nozzle scenario. Using this turf/weed model as a basis, optimal actuator efficacy and herbicide savings would occur by increasing nozzle density from one to 12 nozzles with the context of a single band.
Speakers
PP

Pawel Petelewicz

University of Florida
Co-authors
AS

Arnold Scumann

University of Florida
NA
GM

Gregory MacDonald

University of Florida
NA
MS

Marco Schiavon

University of Florida
NB

Nathan Boyd

University of Florida
NA
QZ

Qiyu Zhou

North Carolina State university
NA
Tuesday September 24, 2024 1:00pm - 1:10pm HST
Lehua Suite

1:00pm HST

International Horticulture Collaboration Session
Tuesday September 24, 2024 1:00pm - 2:00pm HST
A forum for discussion of potential collaborations with regards to international horticulture – i.e. International issues and networking, international consultants, international horticulture groups, etc.
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Coral 4

1:00pm HST

Leadership Class III
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Coral 5

1:00pm HST

Plant Nutrient Management Interest Group Meeting
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Plant Nutrient Management Interest Group
The purpose of this meeting is to align the ASHS mission to develop nutrient management strategies for horticultural field and controlled environment-grown plants, (1) to maximize plant productivity, and (2) to reduce environmental footprints by restricting nutrient loss where it can impact greenhouse gas emissions and water quality.
Moderator
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Sea Pearl 4

1:00pm HST

Public Horticulture Interest Group Meeting
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Tuesday September 24, 2024 1:00pm - 2:00pm HST
Sea Pearl 3

1:05pm HST

PH 1/QUAL - 1-Methylcyclopropene from differing sources: Impact on ‘Red Delicious’ apple during cold storage
Tuesday September 24, 2024 1:05pm - 1:15pm HST
Ethylene affects the postharvest quality and storage life by affecting the physiological changes related to ripening in apple fruits. 1-Methylcyclopropene (1-MCP), a cyclopropane-derived compound, is an effective ethylene inhibitor that blocks ethylene receptors at the cellular level, preventing ethylene effects and delaying its production. Several commercial products are available that provide controlled release of 1-MCP. In this study, a new 1-MCP technology was used, which uses a polymer sheeting material coated with cyclodextrin-encapsulated 1-MCP that is released when exposed to high humidity. Red Delicious apples were commercially harvested in Elbridge, Michigan, and 1-MCP sheets were applied targeting different 1-MCP concentrations (50, 100, 1000, 4000 ppb) and were placed on top of the fruit held in vented cardboard apple boxes in an open room. Another commercial 1-MCP product, Easyfresh®, powder (EF), (Fine Americas, Walnut Creek, CA) was applied at multiple dosages (0, 5, 50, 100, 1000 ppb) to fruit in cardboard apple boxes within sealed chambers as controls. Treated and untreated apples were stored in a cold room at 0 °C temperature and >90% relative humidity. We examined changes in ethylene production, respiration rate, firmness, soluble solids, titratable acidity, weight loss, and superficial scald during 7 months cold storage. The EF treatment was more effective than the 1-MCP sheet treatment for a given target concentration. The effect of 4000 ppb 1-MCP sheet was similar to the 50 ppb EF for the first 3 months of cold storage. The lack of effectiveness of the 1-MCP from sheet was likely due to escape of the 1-MCP from the apple box and off-target sorption by the cardboard.  EF 100 and 1000 ppb concentrations resulted in the lowest ethylene production, respiration rate, weight loss, and superficial scald values in the overall study for 6 months. These concentrations were also influential in preserving firmness, brix, and titratable acidity values. 1-MCP sheet efficacy could be improved by raising the dosage target or changing the architecture and the materials of the boxes in which treatment occurred.
Speakers
OH

Ozge Horzum

Ankara University
NA
Co-authors
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Tuesday September 24, 2024 1:05pm - 1:15pm HST
South Pacific 1

1:05pm HST

VCM 1 - Protecting New Mexico’s Chile Crops from Curly Top Virus through Agrivoltaics
Tuesday September 24, 2024 1:05pm - 1:15pm HST
Chile (Capsicum annuum) consumption and production have been integral to New Mexican culture for over four centuries, and the state is the leading producer of chile (non-bell peppers) in the United States. Chile farmers face adverse conditions due to climate change, water scarcity and disease control. One of the most prevalent chile diseases in NM is Beet Curly Top Virus (BCTV; Curtovirus). BCTV causes chlorotic curled leaves, stunted growth, abnormal or minimal fruit production, and a potentially substantial yield reduction. BCTV is transmitted by beet leafhoppers (Circulifer tenellus), insects that prefer feeding in areas exposed to full sun. Agrivoltaic systems (AVS), the co-location of solar panels in agricultural fields, increases field shade. Advantages of AVS have been examined, but its potential role as a deterrent for pests remains unknown. The aim of this study was to determine the impact of AVS shade on chile yields, beat leafhopper abundance, and BCTV incidence. On 16 May 2023 ‘NuMex Odyssey’, a New Mexico pod-type green chile was transplanted into four solar panel plots and a full sun control at the New Mexico State University Leyendecker Plant Science Research Center, Las Cruces, NM. Plots shaded by solar panels had an average of 15% less light radiation compared to the full sun control. Fruit was harvested on 21 Aug 2023 and sorted into marketable green, blossom end-rot affected, and curly top affected fruit. Preliminary results show that marketable green and blossom end-rot affected fruit yields did not differ between solar panel shaded and the full sun control plots. BCTV affected fruit yield was significantly greater in the full sun control, which also had 55% more trapped beet leafhoppers than the solar panel plots. Initial results show potential for AVS as a method to mitigate the adverse effects on chile yield caused by BCTV. In addition to alleviating crop stress, AVS has the potential to deter beet leaf hoppers while generating electricity, a potential extra revenue for the farmer.
Speakers
ME

Mariela Estrada

New Mexico State University
Tuesday September 24, 2024 1:05pm - 1:15pm HST
Nautilus 1

1:10pm HST

O/LT 1 - Responses of Three Ornamental Species to Saline Water Irrigation
Tuesday September 24, 2024 1:10pm - 1:20pm HST
Water scarcity is a pressing issue in Utah and the Intermountain West, leading to a growing interest in exploring alternative water sources for landscape irrigation. However, alternative water often contains elevated levels of salts, such as sodium chloride (NaCl), which can negatively impact plant growth and appearance. This study investigated the effect of saline solutions on the aesthetic value, growth, and stomatal conductance of three ornamental species: Hibiscus syriacus ‘JWNWOOD4’ (Pink Chiffon® rose of sharon), Viburnum carlesii ‘Spiro’ (koreanspice viburnum), and Vitex agnus-castus ‘SWVACSD’ (lilac chastetree). Plants were irrigated weekly with a nutrient solution at an electrical conductivity (EC) of 0.9 dS·m-1 and saline solutions at 5.0 or 10.0 dS·m-1 for eight weeks. Visual quality was rated weekly using a reference scale ranging from 0 to 5 (0 = dead, 5 = excellent without foliar salt damage). Half of the plants per treatment per species were destructively harvested on 16 Aug (first harvest), and the remaining plants on 4 Sep (second harvest). Plant growth parameters and stomatal conductance were recorded at harvests. Foliar salt damage, such as leaf discoloration and necrosis, was prominently observed in plants, particularly in Viburnum carlesii subjected to elevated EC irrigation. Higher stomatal conductance was consistently observed in all plants irrigated with nutrient solution compared to those under saline irrigation. Interestingly, the salinity treatment did not significantly affect the growth of Vitex agnus-castus, indicating its high salt-tolerance. Notably, Viburnum carlesii displayed higher sensitivity to salinity stress compared to the other two ornamental species. These findings highlight significant variations in responses among the ornamental plant species under saline irrigation at varying EC levels, emphasizing the necessity of employing appropriate alternative water usage strategies.
Speakers
ZW

Zirui Wang

Utah State University
Co-authors
YS

Youping Sun

Utah State University
Tuesday September 24, 2024 1:10pm - 1:20pm HST
Kahili

1:10pm HST

POM 1 - Crown Gall Associated with Higher Risk of New Butt Rot Pathogen in California Almond Orchards
Tuesday September 24, 2024 1:10pm - 1:20pm HST
The wood decay fungus, Ganoderma adspersum, with no prior record in North America has emerged as a pathogen of almond in the San Joaquin Valley within the past decade. Incidence of the disease appears highest in orchards on ‘Nemaguard’ rootstock with high levels of crown gall, a bacterial disease caused by Agrobacterium tumefaciens. The putative association of G. adspersum with crown gall has been hypothesized, but not formally evaluated in the field. In February 2024, over 6,000 trees were surveyed across two orchards and rated for incidence of each disease. Both orchards were on ‘Nemaguard’ rootstock and included ‘Nonpareil,’ ‘Monterey,’ and ‘Fritz’ varieties. Results of Chi-square test for binomial ratings of two categorical variables indicate a significant association between G. adspersum and crown gall infection on all varieties in both orchards. Furthermore, when the variables were fitted using the generalized linear mixed model, infection with G. adspersum (independent variable) was found to have a significant effect on the association (response variable) for ‘Nonpareil’ variety at one site. For each unit increase in the incidence of crown gall, the probability of infection with G. adspersum increased by more than 1×109 fold on ‘Fritz’ and ‘Monterey’ at both sites, and ‘Nonpareil’ at one site, and by more than 87-fold on ‘Nonpareil’ at the second site. The results support the hypothesis that crown gall predisposes almonds to infection by G. adspersum. Further studies are needed to address the mechanism by which crown gall infection predisposes almond to G. adspersum with the long-term goal of improving the economic lifespan of California almond orchards.
Speakers
avatar for Raymond Mireles

Raymond Mireles

University of California Cooperative Extension
Co-authors
Tuesday September 24, 2024 1:10pm - 1:20pm HST
Coral 2

1:10pm HST

UG 1 - Detection of Postharvest Quality of Cut Roses using Vis/NIR Spectroscopy
Tuesday September 24, 2024 1:10pm - 1:20pm HST
Visible and Near-infrared (Vis/NIR) spectroscopy is widely used to analyze plant physiological state and chemical properties non-destructively and rapidly. Recently, Vis/NIR spectroscopy has been used to analyze and estimate the photosynthesis capacity, water content, and soluble solids content (SSC) in various horticultural crops such as fruits and vegetables. Cut roses are often sensitive to water stress under unfavorable conditions during storage and transportation. Water stress of cut flowers generally leads to premature wilting of leaves and petals, thus decreasing the vase life of cut flowers. In this study, we measured the water content and SSC and evaluated the postharvest quality of cut roses using Vis/NIR spectroscopy to screen the quality of cut rose flowers for promoting exportation. Cut roses underwent either wet transport (WT), dry transport (DT), or dry and sucrose treatment, to identify the characteristics of reflectance wavelengths (RW) closely correlated with water content of cut flowers based on Vis/NIR data. Our results showed that dry treatment reduced the vase life and maintenance of positive water balance (PWB) and initial fresh weight of cut roses. Sucrose treatment exhibited a longer duration of retaining PWB and increased SSC in the petals and leaves of cut rose flowers. WT resulted in cut roses with a longer vase life of 1.4 d, compared to DT. DT treatment also decreased the capacity of the cut flowers to maintain PWB by 0.7 d compared to WT. Our results also showed that the Vis/NIR reflectance of the rose petals in the wavelength range 620-720 nm differed among treatments. In particular, the water balance of cut roses showed a positive correlation with RW735 nm and a negative correlation with RW680/RW(620 720) nm, while the SSC of cut roses was positively correlated with RW680/RW(620 720) nm. These results imply that it is possible to evaluate and screen the postharvest quality of rose flowers based on the water relation of cut flowers using Vis/NIR spectroscopy data.
Speakers
ZL

지영 함

안동 국립 대학교
Co-authors
BI

ByungChun In

Andong National University
NA
ST

Suong Tuyet Thi Ha

Andong National University
NA
YK

yongtae kim

Andong National University
Tuesday September 24, 2024 1:10pm - 1:20pm HST
South Pacific 3

1:10pm HST

VSF 1 - Genetics of Adventitious Root Formation in Dormant Bud Cuttings of Grapevines
Tuesday September 24, 2024 1:10pm - 1:20pm HST
Grapevine propagation depends on the formation of adventitious root formation. Vitis riparia and V. rupestris, two native species of North America, serve as the progenitors for the majority of commercially available rootstocks, especially due to their resistance to Phylloxera and ease of propagation. Despite the presence of at least 20 other native Vitis species in North America, many possessing strong resistances to biotic and abiotic stresses, their utilization has been limited by either poor rooting capabilities or insufficient understanding of their rooting potential. This study aims to achieve two main objectives. Firstly, to assess the rooting capabilities of 208 accessions across 20 different species through a dual approach combining traditional evaluation methods with AI-enhanced image analysis. Secondly, to pinpoint the genomic regions linked to rooting ability via a genome-wide association study, which will aid breeding efforts through marker-assisted selection. Preliminary analyses indicate that rooting capability is not solely species-dependent, as there is considerable variation in performance among accessions within the same species. Ultimately, this research will facilitate the development of new, better-adapted rootstocks, which will be crucial in the face of climate change and the increasing prevalence of biotic stresses.
Speakers
SS

Sadikshya Sharma

University of California Davis
I am a PhD candidate working on grape breeding and genomics at the University of California Davis. I am working on developing high-throughput phenotypic and genomic tools for salt and drought tolerance in grapes.
Tuesday September 24, 2024 1:10pm - 1:20pm HST
South Pacific 4

1:10pm HST

WCPM 1/HEMP - Implementing Digital Multispectral 3D Scanning Technology for Rapid Assessment of Hemp (Cannabis sativa L.) Weed Competitive Traits
Tuesday September 24, 2024 1:10pm - 1:20pm HST
The economic significance of hemp (Cannabis sativa L.) as a source of grain, fiber, and flower is rising steadily. However, due to the lack of registered herbicides, hemp growers have limited weed management options. Slow-growing hemp varieties can be outcompeted by weeds for sunlight, water, and nutrients. Hence, easily adoptable integrated weed management (IWM) strategies are essential. Addressing these challenges necessitates novel approaches to identify quantitative phenotypes and explain the genetic basis of key weed-competitive traits. Plant height and canopy architecture may affect crop-weed competition. However, manually measuring these parameters is a time-consuming process. The PlantEye (PE) multispectral 3D scanner was selected as the high-throughput digital phenotyping technology for the evaluation of plant architecture. In this study, the suitability of digital phenotyping was evaluated at the Clemson University Coastal Research and Education Center to screen diverse hemp varieties with different plant habits. Digital plant biomass, plant height, and plant 3D-leaf area (including leaf area index, leaf angle, and light penetration) were periodically monitored. We performed a range of validation tests for morphological features (digital biomass and plant height). A significant correlation (P < 0.001) was observed between digital biomass and manually measured biomass (R = 0.89), as well as between digital height and manually measured height (R = 0.94), indicating the high precision and usefulness of 3D multispectral scanning in measuring morphological traits. Multispectral analyses used in this study are non-destructive, rapid techniques with minimal error and human interference, which have great potential for use in planning weed management.
Speakers
TC

Tyler Campbell

Clemson University
Co-authors
GS

Gursewak Singh

Clemson University
KG

Karla Gage

Southern Illinois University
NA
LS

Lynn Sosnoskie

Cornell University
NA
MF

Michael Flessner

Virginia Tech Univ
NA
PW

Philip Wadl

USDA-ARS
Tuesday September 24, 2024 1:10pm - 1:20pm HST
Lehua Suite

1:15pm HST

PH 1/QUAL - Effects of Seed Sanitizing Treatments on Germination, Shoot Growth and Mineral Nutrient Composition of Four Microgreen Species
Tuesday September 24, 2024 1:15pm - 1:25pm HST
Microgreens are an emerging functional food that is sought after due to dense nutrient compositions as well as vibrant colors and textures. Seed contamination is one of the major food safety concerns as microgreens are consumed raw. Plant pathogenic diseases are also a concern as these can cause a reduction in the growth and quality of the crop. Seed sanitation methods should effectively reduce microbial load with minimal adverse effects on seed germination. The objective of this study was to investigate the effect of four seed sanitizing treatments on germination, shoot production and mineral nutrient concentrations of four microgreen species including chive (Allium schoenoprasum), shiso (Perilla frutescens var. crispa), scallion (Allium fistulosum) and dill (Anethum graveolens). Microgreen seeds were subject to four sanitizing treatments including: Tsunami 100 (400 ppm, 5 min), hydrogen peroxide (3%, 5 min), vinegar (1%, 15 min), and hot water (85°C, 10 sec). Seeds which were treated with deionized water for 10 min were considered to be the control. The microgreens were grown in a greenhouse and were planted into a peat-based substrate and a jute fiber mat in January 2024. Prior to greenhouse production, a germination test was conducted to investigate germination percentage of seeds for each species in response to the four sanitizing treatments or control. Microgreens were assessed for germination, shoot coverage, shoot height, fresh and dry shoot weight, and mineral nutrient concentrations. There was a significant interaction between microgreen species and the sanitizing treatment on fresh and dry shoot weight. The lowest fresh shoot weight for the three species chive, scallion and shiso was 938.2 g·m-2, 976 g·m-2, 907.8 g·m-2, respectively when treated with hot water, with the other three sanitizing treatments and control resulting in statistically similar fresh shoot weights. Dill microgreens showed little difference in fresh shoot weight among the five sanitizing treatments with values ranging from 506.4 g·m-2 in hot water to 868.2 g·m-2 in control. Sanitizing treatment and substrate type both had a significant effect on the shoot height of tested microgreens. Hot water treated microgreens produced the shortest shoots with a mean shoot height of 7.7 cm regardless of species or substrate type. The other four sanitizing treatments produced statistically similar shoot heights ranging from 8.01 cm with vinegar to 8.1 cm with Tsunami 100. The peat substrate increased overall shoot length in tested microgreens compared with jute fiber mats regardless of sanitizing treatment or species.
Speakers
JA

Jacob Arthur

Mississippi State University
Co-authors
GB

Guihong Bi

Mississippi State University
SW

Shecoya White

Mississippi State University
NA
TL

Tongyin Li

Mississippi State University
NA
ZC

Zonia Carvajal

Mississippi State University
NA
Tuesday September 24, 2024 1:15pm - 1:25pm HST
South Pacific 1

1:15pm HST

VCM 1 - Integrating High-resolution Satellite Imagery to Monitor Crop Growth and Yield: A Case Study of Japanese Squash and Onio
Tuesday September 24, 2024 1:15pm - 1:25pm HST
Accurate monitoring of crop growth and estimations of yield are essential for optimizing agricultural practices and ensuring food security. Traditional approaches to monitor crop and map yield in vegetable crops often rely on ground-based observations, which can be time-consuming and labor-intensive. Remote sensing techniques offer a promising alternative by providing frequent and spatially extensive information on crop health and vigor. In this study, we aimed to assess the feasibility of using high-resolution satellite imagery to monitor crop growth and predict yield in Japanese squash (Cucurbita maxima) and onion varieties (Allium cepa) in Hollister, California, over the growing seasons of 2022 and 2023. Daily imagery from PlanetScope with a resolution of 3 m and on-demand 0.5 m imagery from Planet SkySat were utilized. Vegetation indices including the Normalized Difference Vegetation Index (NDVI) and the Soil Adjusted Vegetation Index (SAVI) were calculated at various times during the growing season. Statistical analyses were performed to explore the correlations between these indices and crop yield. The results indicate significant correlations between vegetation indices such as NDVI and SAVI and crop yield in Japanese squash and onion varieties. Higher vegetation index values were associated with increased crop yield, suggesting that these indices can serve as reliable indicators of crop health and vigor. The use of high-resolution satellite imagery allowed for timely and accurate monitoring of crop growth dynamics, facilitating informed decision-making for growers. This study describes the potential of high-resolution satellite imagery and vegetation indices for monitoring crop growth and predicting yield in Japanese squash and onion varieties. The importance of integrating remote sensing techniques into agricultural practices to improve crop management strategies and enhance productivity will be discussed in the presentation.
Speakers
ES

Elia Scudiero

University of California, Riverside
Co-authors
NL

Nan Li

Univeristy of California, Riverside
NA
TS

Todd Skaggs

USDA-ARS
NA
Tuesday September 24, 2024 1:15pm - 1:25pm HST
Nautilus 1

1:20pm HST

UG 1 - Developing Utah’s Own Sap Drinks
Tuesday September 24, 2024 1:20pm - 1:30pm HST
Maple products, such as syrup, sap-based beverages, soft drinks, candies, and butters, are significant agricultural commodities in Canada and the northeastern United States. In recent years, syrup derived from various maple sources, including bigtooth maple (Acer grandidentatum), boxelder maple (Acer negundo), Norway maple (Acer platanoides), silver maple (Acer saccharinum), and sugar maple (Acer saccharum), has been commercialized in the Intermountain West. However, producing one gallon of maple syrup requires approximately 40 gallons of sap and consumes substantial amounts of energy and time due to the need for extensive heating and evaporation. Utilizing sap as a drink can help conserve energy, expand the sap product market, and retain essential minerals with potential health benefits. The purpose of this study was to develop and evaluate beverages made from sap obtained from bigtooth maple, boxelder maple, and Norway maple. Sap samples were gathered from maple trees in Cache County, Utah, filtered through a food-grade filter, bottled in 12 oz glass containers, sealed, and then autoclaved at 121°C. Sugar concentration in both raw and autoclaved sap samples was determined utilizing a refractometer, while comprehensive mineral analyses were conducted by submitting samples to the Utah State University Analytical Laboratories. These drinks contain rich mineral nutrients, varying with plant species. A Utah’s Own designation will be applied to these drinks.
Speakers
CS

Catherine Sun

Sky View High School
Tuesday September 24, 2024 1:20pm - 1:30pm HST
South Pacific 3

1:20pm HST

VSF 1 - Evaluation of Cordon Training System in Blackberry Production
Tuesday September 24, 2024 1:20pm - 1:30pm HST
Commercial blackberry producers use various types of trellising systems to support the canes and prevent damage from wind and added fruit weight. The objective of this study was to determine the fruit yield and quality with a new training and pruning strategy (cordon system) in a T-trellis system. The 2022-23 growing season was the first year of a two-year study to evaluate the conventional winter pruning and training strategy against a modified “cordon” training system, with the Prime-Ark® Traveler cultivar, at the Hampton Roads AREC in Virginia Beach, VA. The study was set up as a completely randomized design with two treatments and six replicates. Each replicate had 3 plants. The conventional pruning and training strategy involved leaving 4 to 6 main canes along with their laterals per plant. The cordon system had 2 to 4 canes pruned to the height of each trellis wire allowing two laterals per cane to extend horizontally along the wire in both directions. The intent was to distribute the fruit weight along the wires, making harvest easier. New primocanes were trained to the wires in the same manner after spent floricanes are removed. All winter pruning was done between 10 and 20 March, 2023. Fertigation was done as per standard extension recommendations. Harvesting was done two to three times per week beginning 30 May and ending 28 August 2023. Fruit yield was collected by replicate and fruits were categorized as marketable Grade 1, Grade 2 or nonmarketable. The nonmarketable fruits were recorded as having white drupelet disorder, diseases, and insect or “other” damage. Fruit size, firmness, total soluble solids (TSS) and pH data were collected on ten Grade 1 berries per harvest week and data were averaged for the season. Statistical analysis was done with two-sample t-test at alpha =0.05. The conventional training and pruning strategy had an overall higher total, marketable and nonmarketable yield. Fruit size was slightly smaller in the cordon system and no differences in firmness, TSS or pH were observed.
Speakers
JS

Jayesh Samtani

Associate Professor, Virginia Tech
Co-authors
EH

Enrique Hernandez

Virginia Cooperative Extension
NA
PR

Patricia Richardson

Virginia Tech, Hampton Roads AREC
NA
Tuesday September 24, 2024 1:20pm - 1:30pm HST
South Pacific 4

1:20pm HST

WCPM 1/HEMP - Evaluating Efficacy of Organic Herbicides on Common Weed Species
Tuesday September 24, 2024 1:20pm - 1:30pm HST
Managing weeds is one of the most significant challenges, especially in organic vegetable production systems. Farmers control weeds in various ways, many of which can have negative environmental impacts. Cultivation is a common way many organic vegetable growers will manage weeds; however, it leads to decreased soil health properties. Hand weeding is extremely time-consuming and labor-intensive. Conventional herbicides have raised public concern for their impact on human health and the environment. Organic herbicide products are used as a burndown, post-emergence product but can be cost-prohibitive. In addition, there is a lack of current research comparing organic herbicide effectiveness on a range of common weed species. This study aimed to explore the efficacy of five Organic Materials Review Institute-approved organic herbicides. These products included citrus oil (Avenger®), ammonium nonanoate (AXXE®), acetic acid (Green Gobbler®), caprylic acid capric acid (HomePlate®), and clove oil cinnamon oil (Weed Zap®). Water was used as a control, and glyphosate (Ranger Pro®) was used as a positive control. Each herbicide was tested on six common weed species: Chenopodium album (common lambsquarters), Portulaca oleracea (common purslane), Setaria viridis (L.) Beauv. (green foxtail), Digitaria sanguinalis (L.) Scop. (large crabgrass), Amaranthus retroflexus (redroot pigweed), and Abutilon theophrasti (velvetleaf). Products were sprayed according to label recommendations using a calibrated spray chamber at the Iowa State University greenhouses. Each weed species, 10 plants per replication, was sprayed after reaching an average height of seven centimeters. Percent weed cover using digital image analysis software (Turf Analyzer) and percent visual injury was recorded. These data parameters were collected 24 hours, 3 days, 10 days, 17 days, and 21 days following herbicide application. Weed biomass was collected and dried 21 days after herbicide application for all species. AXXE® was a fast-acting herbicide on common lambsquarters, common purslane, redroot pigweed, and velvetleaf. These species showed over 85% injury three days after AXXE® application. Weed Zap® stunted the majority of examined weed species soon after application, but the injury effects were less significant 21 days after application. Visual injury assessments showed Avenger®, Green Gobbler®, HomePlate®, and Weed Zap® had no significant injury on green foxtail and large crabgrass 21 days after herbicide application. Results from this study provide growers with practical and applied data to make informed decisions regarding the use of organic herbicides.
Speakers
avatar for Carly Strauser

Carly Strauser

Iowa State University
Graduate Research Assistant, Department of Horticulture at Iowa State University
Co-authors
AN

Ajay Nair

Iowa State University
NA
Tuesday September 24, 2024 1:20pm - 1:30pm HST
Lehua Suite

1:25pm HST

PH 1/QUAL - Towards Development of a Consumer-Preference Driven Digital Guide to Apple Fruit Cultivar Selection
Tuesday September 24, 2024 1:25pm - 1:35pm HST
There are over 7,500 apple varieties grown worldwide, each with its own set of organoleptic characteristics such as flavor, texture, and appearance. However, no more than 150 varieties have been introduced broadly in the global market. Consumer preference for apples is influenced by a complex interplay of factors beyond taste. The sheer variety of apples available in the market creates a valuable opportunity for a digital app that can help consumers navigate and select the best options based on their quality trait preferences. This project, in cooperation with U.S. Apple Association, aims to ultimately develop a digital app that will recommend apple varieties based on consumer’s preferences regarding sweetness, sourness, juiciness, crispiness, flavor, color, texture, and nutrition content. Thus, we examined the relationship between various sensory and physico-chemical data to understand their significance in apple selection. Five cultivars of apples grown organically (‘Ambrosia’, ‘Cosmic Crisp’, ‘Gala’, “Sugar Bee®’, and ‘Sweet Tango’) were purchased from a retail store in Mid Atlantic area during the winter season. Thirty apples of each cultivar (n=30) were measured for volume, weight, height, width, specific density, surface area, circumference, fizziness and for skin color (L*, a*, b*, hue angle, chroma). Firmness parameters and acoustic texture parameters were also measured. Additionally, total juice content, soluble solid content (SSC), titratable acidity and pH were assessed. Consumer panels (n=45: female=22, male=23) were conducted to evaluate traits including sweetness, sourness, flavor, texture/mouth feel, and overall eating quality (OEQ) using a five-point scale. Consumers displayed a stronger preference for ‘Cosmic Crisp’ and ‘Sugar Bee®’ varieties compared to ‘Gala’ and ‘Ambrosia’. This preference is driven by significantly higher consumer ratings for firmness, sweetness, and sourness of ‘Cosmic Crisp’ and ‘Sugar Bee®’. As highlighted in previous studies, correlations between consumer-rated sensory scores and their corresponding instrumental measurements were low. Furthermore, OEQ showed a stronger correlation with sensory ratings (r=0.54-0.84 ) than instrumental measurements (r=0.02 to 0.49). This suggests that consumer evaluation is critical, and may be a more reliable indicator, for the development of a digital app, compared to instrumental measurements. An accompanying consumer survey (n=30) indicated that crispness is a key factor considered by consumers when choosing apples. This project provided valuable insights and potential issues when developing a user-friendly app for consumers. It identified the dominant factors influencing apple selection and showed methods to cross-validate sensory ratings with corresponding instrumental measurements.
Speakers
EP

Eunhee Park

USDA-ARS
NA
Co-authors
BZ

Bin Zhou

USDA-ARS
NA
CG

Christopher Gerlach

US Apple Association
NA
JF

Jorge Fonseca

USDA-ARS
NA
RO

Regina O'Brien

United States Department of Agriculture
NA
VG

Verneta Gaskins

USDA-ARS, Beltsville Agricultural Research Center
WJ

Wayne Jurick

USDA-ARS
NA
Tuesday September 24, 2024 1:25pm - 1:35pm HST
South Pacific 1

1:25pm HST

VCM 1 - A New Tool to Manage Water and Nutrients in High Tunnel Tomato Production
Tuesday September 24, 2024 1:25pm - 1:35pm HST
Much of the tomato production on market farms in the northeastern United States utilizes high tunnels. Tunnels protect soils from rainfall, reducing leaching of nutrients. However, if nutrients are accumulating below the root zone in tunnel soils lateral flow could be moving the nutrients beyond the covered area, resulting in leaching. From July 2020 to October 2022 we monitored soil moisture, soil temperature, and mineralization and movement of nitrate and phosphate in high tunnel tomato production on five commercial market farms (2 in Connecticut and 3 in Rhode Island). We also tracked irrigation water and fertilizer applications. Activated mixed-bed resin capsules were buried at 30 cm depth in transects running across the width of each high tunnel and extending 1 m past the tunnel perimeter on each side. Resin capsules were exchanged in March, July and October of each year and analyzed for captured nitrate, ammonium and phosphate. Soil P in the tunnels ranged from 16 to 363 kg/ha and soil K from 207 to
Speakers Co-authors
JG

Josef Gorres

University of Vermont
NA
SG

Shuresh Ghimire

University of Connecticut
NA
Tuesday September 24, 2024 1:25pm - 1:35pm HST
Nautilus 1

1:29pm HST

Ornamental Plant Breeding (OPB)
Tuesday September 24, 2024 1:29pm - 2:00pm HST
Create Novel Interspecific Hybrids between Tuberous Begonia and B. semperflorens by Using Embryo Rescue Technique - Yen Ming Chen
Breeding the Unbreedable: Innovating the Generation of Sterile Triploid Lantana through Open-Pollinated Interploidy Crosses - Brooks Parrish
Tetraploid plants of Samanea (Albizia) saman on diploid roots grew similarly to mixoploid and diploid plants on diploid roots while tetraploid plants on tetraploid roots were inferior to triploid plants on triploid roots - Alberto Ricordi

Moderator
BP

Brooks Parrish

University of Florida
Tuesday September 24, 2024 1:29pm - 2:00pm HST
South Pacific 2

1:30pm HST

OPB - Create Novel Interspecific Hybrids between Tuberous Begonia and B. semperflorens by Using Embryo Rescue Technique
Tuesday September 24, 2024 1:30pm - 1:40pm HST
Genus Begonia is prominent ornamental bedding and potted flower crop, encompassing types such as Rieger Begonia (Begonia × hiemalis), Tuberous Begonia (Begonia tuberhybrida), and B. semperflorens, which are extensively cultivated. Building upon the breeding methodology of Rieger Begonia, this study endeavors to utilize Tuberous Begonia as the maternal parent and integrate the attributes of B. semperflorens to develop innovative interspecific hybrid varieties. Interspecific hybridization was accomplished by using Tuberous Begonia 'Fortunate' as the female parent and B. semperflorens as pollen donor through embryo rescue techniques, resulting in successful interspecific offsprings. Flow cytometry analysis revealed the expected DNA content combination in the hybrids. Furthermore, Random Amplified Polymorphic DNA (RAPD) analysis confirmed the authenticity of the interspecific hybrids by exhibiting specific bands of both parents. The plant type, basal branching habit, and leaf shape of the hybrids resembled those of the male parent, B. semperflorens, while the double flower characteristic inherited from the female parent. Additionally, the hybrids exhibited year-round flowering without requiring photoperiod treatment and showed no apparent dormancy, rendering them suitable for continuous production. These hybrids are also exhibiting robust branching habits and possess distinctive plant traits compared to commercially available Rieger Begonias. They are particularly suited for cultivation in hot and humid regions. Evaluation of production and growth advantages indicated their capability for year-round supply and commercial production. Applications for Plant Variety Rights have been submitted for these hybrids in Taiwan.
Speakers
YM

YEN MING CHEN

National Chung Hsing University
Tuesday September 24, 2024 1:30pm - 1:40pm HST
South Pacific 2

1:30pm HST

UG 1 - Effect Of Temperature Alterations On Phytochemicals Accumulation Among Two Variety Of Feverfew Cultivars
Tuesday September 24, 2024 1:30pm - 1:40pm HST
Feverfew, a member of the Asteraceae family, has a long history of traditional use for various health purposes, including anxiety and depression management, and alleviating arthritis and inflammation. Feverfew consists of a specific chemical compound named parathenolide which is a phytochemical naturally found in Tanacetum parthenium, which plays a significant role in being responsible for feverfew’s anti-inflammatory effects. This study aims to investigate the effect of the temperature changes in parathenolide accumulation among two varieties Matricaria Tetra White and Matricaria Tetra Virgo Feverfews based on their genetic differences. Feverfew cultivars will be grown in a container containing potting mix which has enough nutrients for plant growth and development. The two varieties will be randomized with each variety receiving varying temperature differences (low, medium, and high). The accumulation for parathenolide will be analyzed using HPLC analysis to evaluate the accumulation of the phytochemical in each variety in response of the differences in temperatures. Among the phytochemicals of interested in this study include an understanding the effect of temperature on the accumulation and synthesis of the phytonutrients can highly assist scientists and health care professionals to increase and promote medicinal plants. Feverfew can benefit low-income communities like urban areas where majority of the community members are incapable to afford medication that can treat sickness such as anxiety and depression.
Speakers
JG

Jalynn Greer

Kentucky State University
I am interested in botany specializing in herbalism. My hobby is crocheting.
Co-authors
TN

THEONESTE NZARAMYIMANA

Kentucky State University
Tuesday September 24, 2024 1:30pm - 1:40pm HST
South Pacific 3

1:30pm HST

WCPM 1/HEMP - Effect of Early and Late-post Emergence Herbicides on Weed Suppression, Crop Injury, and Biomass Yield of Industrial Hemp
Tuesday September 24, 2024 1:30pm - 1:40pm HST
Industrial hemp is receiving attention for its numerous benefits, particularly in the fiber industry. Weed competition is a primary concern for hemp cultivation causing reduced yields and inferior-quality fiber. However, little is known about herbicide application in hemp since a limited range of herbicides are available for hemp production. Therefore, a field study was conducted in 2023 to investigate the effect of different herbicides and application timings on weed suppression, crop injury, growth, and biomass yield of hemp. A randomized complete block design was conducted with six herbicide treatments including, early POST [2 weeks after planting (WAP)] and late POST (5 WAP) emergence applications of S-metolachlor, clopyralid, and ethalfluralin, with an untreated control to make comparisons. Plant stand showed no significant difference among treatments. Early POST herbicides application significantly reduced the weed biomass compared to untreated control at 7 WAP. By 10 WAP, weed biomass became comparable across treatments. At harvest, untreated control recorded comparatively higher weed biomass than early POST treatments and late POST ethalfluralin. Plant height remained non-significant among treatments until 10 WAP. At harvest, control showed no variation with late POST treatments but recorded an average 63% lower plant height than early POST applications. Treatments showed no significance for hemp biomass at 10 WAP. However, early POST S-metolachlor and ethalfluralin herbicides exhibited lower weed biomass and greater plant height, resulting in greater hemp biomass accumulation compared to untreated control at harvest. In conclusion, early POST S-metolachlor and ethalfluralin could be used as POSTemergence herbicides for hemp cultivation.
Speakers
RS

Rupinder Saini

Texas Tech University
Co-authors
CT

Calvin Trostle

Texas And M Agrilife
NA
JM

Jasleen Makkar

Texas Tech University
NA
PB

Preetaman Bajwa

Texas Tech University
NA
SS

Sukhbir Singh

Texas Tech University
NA
Tuesday September 24, 2024 1:30pm - 1:40pm HST
Lehua Suite

1:35pm HST

PH 1/QUAL - Evaluating Fresh-cut Lettuce Quality via Image Analysis
Tuesday September 24, 2024 1:35pm - 1:45pm HST
Visual quality is an important factor for consumer purchasing decisions of fresh-cut lettuce. Consumer behavior towards produce quality has been studied via traditional human evaluations. For sensory studies, quality evaluations are commonly done by trained human panels and consumer panels. This study was to investigate the possibility of replacing human evaluation with a machine based approach, using image capturing and analysis, and determine whether efficiency of produce quality analysis can be enhanced. Three types of data were collected: (a) consumers’(n=200) evaluation of lettuce on the picture, (b) instrumental analysis of samples (package head-space gas composition (O2, CO2) and electrolyte leakage), (c) image analysis of lettuce on the pictures. For image analysis, ImagePro’s smart segment tool was used to classify the lettuce samples into five regions: adult leaf, baby leaf, rib, rib degradation, and leaf degradation. This was used to find and calculate L*a*b, hue angle, chroma values, area, and relative area of these regions. Lettuce samples consisted of four cultivars (Green Forest, King Henry, Parris Island Cos, PI 491224). Samples were measured on day 7, 10, and 13 of storage. To predict browning score, data sets (b) and (c) were fed into a regression algorithm. The scores assigned by trained panels served as the target variables. The results showed a strong correlation between consumer’s browning score on the pictures and predicted scores generated by the regression model (r=0.74). Interestingly, removing the instrumental data set (b) did not worsen the model’s performance. The model achieved an R2 of 0.92 and RASE of 8.90 when using trained data sets (a) and (c), and an R2 of 0.91 and RASE of 8.53 when using trained data set (c) only. While a correlation coefficient of 0.74 indicates a promising relationship between image analysis and human evaluation of browning score, it’s not sufficient to definitively replace human evaluation. Further studies with larger datasets and exploration of more advanced machine learning models could lead to a more robust statistical model.
Speakers
EP

Eunhee Park

USDA-ARS
NA
Co-authors
EE

Ella Evensen

USDA-ARS
NA
IS

Ivan Simko

USDA-ARS
NA
JF

Jorge Fonseca

USDA-ARS
NA
YL

Yaguang Luo

USDA/ARS
NA
Tuesday September 24, 2024 1:35pm - 1:45pm HST
South Pacific 1

1:35pm HST

VCM 1 - Soil Moisture Sensors Allow for Resilient Tomato Production in Organic Systems
Tuesday September 24, 2024 1:35pm - 1:45pm HST
Soil moisture sensors have enabled continuous soil water status monitoring and became widely available to commercial growers. The use of soil moisture sensors that measure volumetric soil water content can be a useful tool to diminish or avoid over-irrigation addressing specific water requirements according to soil characteristics. However, the frequency of irrigation events, or a proper irrigation scheduling, using soil moisture sensor varies according to soil type, and the performance of soil moisture sensors as a tool to determine irrigation events on sandy soils used for organic vegetable production, particularly tomato, have not been evaluated up to date. Thus, the study objective was to evaluate the use of three irrigation scheduling strategies to enhance irrigation management in organic tomato production in the southeastern U.S. Field experiments were conducted on the organic unit at E.V. Smith Research and Extension Center from Auburn University, located in Shorter, AL in 2022 and 2023. Three irrigation scheduling treatments were tested: systematic irrigation (SYS), crop water demand (CWD), and soil water status method (SWS). In both years, results indicated that SWS had a higher biomass accumulation than CWD and SYS; consequently, tomato yield increased in the SWS compared to the two other treatments. Yield increments were 14% between SWS and CWD, and 25% between SWS and SYS. Irrigation water savings were also the highest for the SWS treatment, resulting in 72% water savings compared to SYS and 54% to CWD in 2022; while the SWS used 65% less water than SYS and 55% less than CWD in 2023. In general, rainfall events had an impact on strategies used to determine irrigation events. Among the studied irrigation scheduling methods, the SWS had a better performance in terms of fruit growth, biomass accumulation, and overall yield compared to CWD and SYS. Considering the global need for sustainable practices, the SWS treatment shows up as one of the best alternatives to the current grower standard practice, which consist in the SYS.
Speakers Co-authors
CR

Camila Rodrigues

Auburn University
GB

Guilherme Bueno

Auburn University
NA
TC

Timothy Coolong

University of Georgia
WF

Wheeler Foshee

Auburn University
NA
Tuesday September 24, 2024 1:35pm - 1:45pm HST
Nautilus 1

1:40pm HST

OPB - Breeding the Unbreedable: Innovating the Generation of Sterile Triploid Lantana through Open-Pollinated Interploidy Cros
Tuesday September 24, 2024 1:40pm - 1:50pm HST
This study presents a groundbreaking field breeding strategy for Lantana camara, a plant celebrated for its ornamental value yet criticized for its invasive tendencies. Traditional hand pollination techniques for lantana are labor-intensive, as each flower produces only one seed, making the generation of significant populations time-consuming. Although open pollination represents an alternative for seed production, the reliability of generating sterile triploids through interploidy crosses has been questionable. Addressing these challenges, this research innovatively employs open-pollinated breeding between diploid and tetraploid populations to efficiently produce sterile triploid cultivars. The method leverages male-sterile tetraploids for open pollination with female-sterile, male-fertile diploids, yielding 544 triploid seeds within five weeks and proving the effectiveness of interploidy hybridization. Moreover, diploid populations in an all-by-all cross setup produced over 2,000 seeds in the same period, eliminating the need for hand pollinations. Nonetheless, the development of tetraploid breeding lines encountered obstacles due to insufficient pollen transfer, likely resulting from low pollen production, although selfing within hybrid lines remained feasible in an open-pollinated field setting. These findings significantly advance the fields of ornamental breeding and invasive species management, providing fresh perspectives on the cultivation and control of Lantana camara. Demonstrating the capability to rapidly produce large volumes of sterile triploid lines with minimal labor, this study lays the groundwork for the broader availability of non-invasive Lantana camara alternatives in the future.
Speakers
BP

Brooks Parrish

University of Florida
Co-authors
ZD

Zhanao Deng

University of Florida
Tuesday September 24, 2024 1:40pm - 1:50pm HST
South Pacific 2

1:40pm HST

UG 1 - Increased Airflow Improves Yields of High Density Indoor Micro Dwarf Tomato
Tuesday September 24, 2024 1:40pm - 1:50pm HST
Indoor agriculture production allows producers to control all of the environmental parameters given a system with enough sophistication. However, the expense of comprehensive systems is prohibitive from an economic standpoint, in most cases. Identifying the most important parts of the plant environmental experience to control is a critical part of building efficient and economical indoor farms. In this study with temperature, nutrition, lighting and other aspects of the farm being controlled, airflow was manipulated. Micro dwarf cherry tomato varieties (Solanum lycopersicum ‘Tiny Tim’ and ‘Pinocchio Orange’) were grown in an NFT style hydroponic systems for 90 days. All plants were grown in a greenhouse with natural and supplemental lighting. Control plants received airflow native to the greenhouse environment, mixing fans, ridge line vents and pad fan based HVAC control. The treated plants experienced a “high air flow” condition. The results indicate a clear improvement in the fruit weight, number of fruit per plant, and fruit diameter for plants which experienced increased airflow. These results, while preliminary, demonstrate the clear advantage of additional airflow targets for indoor plant production and provide the basis for an important indoor production lever to improve yields in micro dwarf cherry tomatoes.
Speakers
MA

Matthew Arrington

Brigham Young University
Dr. Matt Arrington is an assistant professor of applied plant science at Brigham Young University. Matt graduated with his PhD in horticulture from Washington State University and Masters degree from Oregon State University. His areas of research focus include crop efficiency in controlled... Read More →
Co-authors
NG

Nathan Grooms

Brigham Young University
NA
Tuesday September 24, 2024 1:40pm - 1:50pm HST
South Pacific 3

1:40pm HST

WCPM 1/HEMP - Growing Field Hemp in Louisiana, a second attempt.
Tuesday September 24, 2024 1:40pm - 1:50pm HST
Field production hemp trials were conducted in 2020 and 2021 in Baton Rouge, Louisiana without success. In both seasons, the hemp was planted in spring and harvested in early summer. Over 50% of the plants dies from disease and or initial root rot because of excessive rain and wet soils. Faculty at the LSU AgCenter were successful in growing hemp in 2021 in greenhouse settings but realize not all growers can afford such structures. Therefore, field trails were established in the fall 2023 (October) and early spring (January and February 2024) planting dates. Day length neutral hemp was planted. The off-season trials were planted in attempt to field produce hemp during cooler and drier weather to prevent plant loss from disease. Unfortunately, the field plantings in October 2023, January and February 2024 yielded small plants with little harvestable flowers. At this time, we do not recommend field planting hemp in south Louisiana.
Speakers
KF

Kathryn Fontenot

LSU AgCenter
Co-authors
AH

Alessandro Holzapfel

Louisiana State University Agricultural Center
GL

Gabriel LoCoco

LSU AgCenter
NA
HK

Heather Kirk Ballard

SPESS
Heather Kirk-Ballard is an Assistant Professor and state extension specialist of Consumer Horticulture for the LSU AgCenter. She is the host of the Get It Growing ™ extension program focusing on home gardening that is disseminated weekly through video to news stations and in print... Read More →
RL

Reeve Legendre

LSU AgCenter
NA
Tuesday September 24, 2024 1:40pm - 1:50pm HST
Lehua Suite

1:44pm HST

Vegetable Crops Management 1 (VCM 1)
Tuesday September 24, 2024 1:44pm - 3:45pm HST
Nutsedge Management Through Soil Steaming - Shaun Broderick 
Early Season Soil Tarping Impacts on Weed Pressure and Onion Production in Eastern South Dakota - Hannah Voye 
Associations Among Crop/Weed Management Practices and Environmental Factors Highlight Challenges Facing U.S. Snap Bean Production  - Martin Williams 
Impact of Early Season Tarping on Soil Conditions and Weed Populations in North Central United States Vegetable Production Systems - Carly Strauser
Applying Advanced Lighting Practices for Vegetable Propagation - Rose Seguin
Evaluating the Effect of Three Algae Extracts Application on Three Crops Growth and Yield in Hawaii - Amjad Ahmad
Using the Feekes Growth Stage Scale to Predict the Carbon to Nitrogen Ratio of Cereal Cover Crops - Eric Brennan
Evaluating the effect of fertilization and controlled-water deficit on growth and yield of compact vegetable plants - Michael Fidler
Moderator
SB

Shaun Broderick

Mississippi State University
Tuesday September 24, 2024 1:44pm - 3:45pm HST
Kahili

1:45pm HST

VCM 1 - Physiology of Heat Tolerant Tomatoes: Transplanting Through Harvest
Tuesday September 24, 2024 1:45pm - 1:55pm HST
Consumers are motivated to purchase locally grown tomatoes for a maximum flavor experience. With this demand, tomatoes are highly valuable in the local food system and one of the most profitable crops for small, diversified farms. Tomato production in Oklahoma, and other warm climates, can be difficult with the fruit’s temperature requirements for fruit set. Optimum conditions are available for a short period in Oklahoma. The additional threat of climate change could present even more challenging growing conditions in the future. There are heat tolerant tomatoes available, but these cultivars still have an upper limit for stress exposure. Previous research shows that there are distinct physiological differences between heat tolerant and heat sensitive cultivars, but these evaluations focus primarily on the early stages of the plant’s development. We aim to investigate the differences in cultivars throughout the entire plant life cycle. A field experiment will include six cultivars at different planting dates, showing a range of responses. The three planting dates will impose different temperature regimes throughout plant development. Physiological measurements will be recorded at regular intervals from transplanting through harvest. These parameters will include chlorophyll fluorescence, stomatal conductance, and electrolyte leakage. The results will assist with development of a model that enhances Oklahoma tomato production capacity through optimizing cultivar selection.
Speakers Co-authors
JM

Justin Moss

Oklahoma State University
NA
Tuesday September 24, 2024 1:45pm - 1:55pm HST
Nautilus 1

1:45pm HST

VCM 1 - Nutsedge Management Through Soil Steaming
Tuesday September 24, 2024 1:45pm - 2:00pm HST
Soils host weeds, pathogens, and insects that can cause crop damage and reduce yield. Many methods have been developed to reduce these pressures within the soil, including soil solarization, chemigation, anaerobic soil disinfestation, and soil steaming. We have utilized soil steaming to reduce weed seeds and soil infestation in high tunnel and field tomato (Solanum lycopersicum) production. While it successfully reduces most weed species and southern blight (caused by Athelia rolfsii) in tomatoes, the emergence of nutsedge (Cyperus spp.) in soils with established populations can increase after steaming. Our research goal was to evaluate the efficacy of various soil preparation methods prior to steaming to allow the steam to penetrate the soil and target nutsedge directly. Except where noted, the field was first chisel plowed, disced, and then shaped into 2-foot-wide by 6-inch-tall beds. We compared 8 preparation methods for controlling nutsedge: a no-till control, herbicide control using S-metolachlor and halosulfuron-methyl, 6-inch-tall bed size, 12-inch-tall bed size, chisel plowed row, black plastic mulch, 4-inch-deep trenches on no-till, and 6-inch-deep trenches on no-till. Four trenches were cut into the soil with a soil trencher for each plot. Four replicates were included in a completely randomized design. Half of each bed was steamed until temperatures reached 160 °F, 4 inches deep, except for the herbicide beds and mulched beds, which were left unsteamed. Four sets of temperature probes were placed 12, 8, 6, and 4 inches deep in the soil and temperatures and used to monitor temperature changes in steam soils over time. Nutsedge coverage was visually estimated by placing a 1 by 6-foot rectangular PVC frame in each row over a representative section. 12-inch-tall beds had nearly 100% nutsedge coverage, while 6-inch-tall beds had nearly 50%. Herbicides reduced nutsedge coverage to 29%, and the plastic mulch reduced coverage to 8%. The steamed no-till, 4-inch trench, 6-inch trench, and chisel-plowed beds had no nutsedge emergence through the trial. The 6-inch-tall beds had lower temperatures at 6 and 8 inches deep than the other methods, which could account for the observed increases in nutsedge emergence post steaming. The time-consuming nature of soil trenching would make it impractical for most horticultural production settings; however, the chisel plow and no-till could be readily adopted. Determining effective methods to prepare the fields for soil steaming to reduce or eliminate nutsedge will make soil steaming a more viable method for organic farmers facing nutsedge pressures.
Speakers
SB

Shaun Broderick

Mississippi State University
Co-authors
CC

Christine Coker

Mississippi State University
TM

Te Ming Tseng

Mississippi State University
Tuesday September 24, 2024 1:45pm - 2:00pm HST
Kahili

1:45pm HST

Workshop: Mediating Tropical Plant Pathology Challenges Across a Range of Crops and Diseases in Hawaii
Tuesday September 24, 2024 1:45pm - 3:45pm HST
Tropical crops have a tremendous impact on global food systems and are well represented in Hawaii. There are many different diseases (bacterial/viral/fungal) that can impact yields. In this session, we invite an audience from a broad pool of research interests and backgrounds to attend and learn about a range of food and forestry crops that are important in Hawaii, including papaya, sweetpotato, the native koa tree and banana and the production systems unique to these crops. The wide range of crops from tuber, to fruit, to forestry has led to a variety of challenges that have attracted less attention compared to pathology problems associated with temperate crops. Topic presentations in these areas will be presented by and from the perspective of university, non-profit, and USDA ARS researchers and a local commercial grower and will be followed by a panel discussion aimed at highlighting the many different techniques that have been used to overcome these challenges and how they are relevant to the broader agricultural research and commercial production sectors. Through these facilitated topic discussions, we hope to convey the scope of tropical diseases that occur as well as how to overcome them given different crop-specific constraints and their relevance to climate change.

The goal of the workshop is attract and engage a wide audience both outside as well as those working in tropical horticulture and to educate and bring together different perspectives of university and federal scientists, extension educators, graduate students, post-docs and industry on the current status of pathology problems that occur in various tropical crops in Hawaii. The workshop will discuss the approach and options used in different specialty crops to address the multitude of pathogens that threaten tropical crop production, the importance of germplasm collections, and successful strategies for the future in the face of global climate change. Information and exchange through panel discussion from presenters supporting agriculture and the public representing different entities including various research organizations and a producer, will highlight contributions from the different sectors and their unique and common perspectives and cross synergies. Through these talks and discussions, we hope to convey the scope of tropical diseases that occur as well as how to overcome them given different crop-specific constraints. We aim to highlight these successful strategies and their relevance to a broader sector of agriculture and to future research on emerging problems impacting temperate and other regions due to climate change.

Coordinator(s)

Jon Suzuki, USDA ARS DKI U.S. PBARC, Hilo, HI, United States

​​​​Participants:

Dr. Nathan Fumia (HARC - Hawaii Agricultural Research Center) – Understanding the role of selection on fungal disease tolerance in Acacia koa, an endemic Hawaiian hardwood (8 minutes). 
A common occurrence during neo-domestication is the interplay of traits such as seedling vigor and disease resistance. The focus of this study is the effect of crossing on a wild species being selected for a domesticated form, including decisions such as number of parents, number of crosses, and number of progeny.  Our aim is to begin breeding scheme development for wild species (neo-domestication) using Acacia koa as a novel study system. Breeding population size was changed in the koa orchard through thinning of individuals, a form of pollen control in the population, with the major criterion being a low durability of resistance where trees succumb to disease over time, caused by Fusarium oxysporum. This is an opportunity for insight during the development of expectations in population improvement through augmented crossing parameters, informing situational changes through breeding cycles in neo-domestication programs.
Dr. Anna McCormick (University of Hawaii at Manoa) – Examining viral presence in collections of Hawaiian heirloom sweetpotato varieties (8 minutes). 
Sweetpotato has been a staple crop in the Hawaiian Islands since Polynesians settled the islands ~1,200 years ago. Previous work has established that Hawaiian Heirloom sweet potato varieties represent unique germplasm that are more closely related to each other than varieties from other parts of the world. While much work has been done characterizing Hawaiian heirloom plant genetics, much less work has been done characterizing viral genetic presence and diversity. In this study we explored viral presence across an extant collection of 70 Hawaiian heirloom varieties sourced from five different botanical collections over three Islands (O’ahu, Maui and Big Island Hawai’i). Samples were examined for the presence of four viruses from the family Potyviridae namely; Sweet potato virus G (SPVG), Sweet potato virus C (SPVC), Sweet potato virus 2 (SPV2), Sweet potato feathery mottle virus (SPFMV), and one from the family Geminiviridae; Sweet potato leaf curl virus (SPLCV). We found high levels of virus across all collections, including many instances of double and triple infections. These findings have large implications for conservation and local fresh markets.
Dr. Mark Shankle (Mississippi State University) – Research and discovery of best practices for U.S. sweetpotato clean foundation seed (CFS) programs. (8 minutes)
Sweetpotato is an important crop for the U.S. and worldwide.  Infection by viruses which accumulate over time in this and numerous other major perennial crops cause major yield losses annually.  The problems in sweet potato are being addressed through Sweetpotato CleanSEED, a multi-state, transdisciplinary funded research project funded by a USDA-NIFA-SCRI grant to develop strategies that improve sweetpotato crop health and yield through developing quality control standards for producing clean foundation seed, improved detection methods, identification of undiscovered viral diseases, and development of cultural practices for efficient clean foundation seed production in both the laboratory and greenhouse to reduce disease transmission in this clonally propagated crop.
Ryan Domingo (USDA ARS U.S Pacific Basin Agricultural Research Center) - Identifying Carica papaya cultivars demonstrating increased partial resistance towards Phytophthora palmivora utilizing a novel rapid phenotyping assay. (8 minutes)
Extensive production loss and mortality of Carica papaya is associated with Phytophthora palmivora in Hawaii and other papaya growing regions of the world. Currently there is no commercial papaya cultivar fully resistant against P. palmivora, however it is important to identify those that contain partial resistance reducing pathogen proliferation. This talk will explore a novel rapid phenotyping assay quantifying P. palmivora growth along papaya seedling stems comparing several genotypes within the USDA germplasm collection. Implications resulting from this study provides farmers, breeders and other stakeholders insight towards cultivars displaying increased partial tolerance towards P. palmivora.
Gabriel Sachter-Smith  (Hawaii Banana Source) - Maintaining commercial vitality of the banana industry through germplasm resources and strategies to mitigate disease (8 minutes).  
Bananas have been grown in Hawaii since the first waves of Pacific Islander migrations starting over 1000 years ago. Today, bananas represent one of the most widely consumed fresh produce items in Hawaii, despite a steady downward trend in local production since the introduction of Banana bunchy top virus (BBTV) in 1989. To date, no commercially viable cultivar with strong resistance to BBTV has been identified or created, and various ways to combat the virus used in other parts of the world have proved challenging to apply in Hawaii. However, the pressure of the virus and overall impact on a farm can be mitigated using a combination of cultur
Tuesday September 24, 2024 1:45pm - 3:45pm HST
Coral 2

1:50pm HST

OPB - Tetraploid plants of Samanea (Albizia) saman on diploid roots grew similarly to mixoploid and diploid plants on diploid
Tuesday September 24, 2024 1:50pm - 2:00pm HST
Many legume trees are notorious for their prolific production of seedpods, which are usually large and in many cases stink when cracked open. Such pods affect both the beauty and sensory perception of the tree, and may be slippery and hazardous on walking surfaces. For example, Samanea (Albizia) saman, which has naturalized in many tropical and subtropical places and is commonly known in Hawaii as monkey pod tree, is a favorite landscape tree in Hawaii for its large canopy, especially in parking lots and parks. Unfortunately, this species produces a large amount of sticky pods that stick to shoes and tires, and can create an objectionable mess, a high volume of green waste and high maintenance of parking lots. The seedpods are heavy to rake and can cause damage to lawn mower blades. Seedless cultivars would have no potential to become invasive and their maintenance cost would be much lower. Seed-bearing ornamental plants can be converted to triploid, non-seed-bearing forms, and thereby eliminate their invasiveness and reduce their maintenance. Triploid plants rarely produce functional gametes, because they do not undergo normal meiosis, and the resulting sterility accounts for the economically valuable seedlessness of triploid bananas, limes, and seedless watermelons. Sterile nursery plants can be used for landscaping virtually without any possibility to become invasive. In a field trial at the University of Hawaii Waimanalo Research Station, it was observed that tetraploid plants of Samanea (Albizia) saman on diploid roots grew similarly to mixoploid and diploid plants on diploid roots. These tetraploid plants were developed by treating the apical meristem of diploid seedlings with 0.1% colchicine for 48h. Therefore, the root system remained diploid, while the above ground portion of the plants were tetraploid. However, tetraploid plants on tetraploid roots, grown from seeds harvested from tetraploid induced plants, were inferior to triploid plants on triploid roots. Triploid plants were almost double in size (67% taller, had 109% wider canopy, and 90% larger DAB, n=8). This is the first time that this phenomenon has been documented in Samanea spp.
Speakers
AR

Alberto Ricordi

University of Hawaii at Manoa
Co-authors
KL

Kenneth Leonhardt

University of Hawaii at Manoa
NA
Tuesday September 24, 2024 1:50pm - 2:00pm HST
South Pacific 2

1:50pm HST

UG 1 - Assessing the Impact of Urban Environments on the Biomolecular Composition of 'Mosco' Chili Peppers
Tuesday September 24, 2024 1:50pm - 2:00pm HST
The rapid increase in urban populations and urbanization, coupled with the increasing demand for natural resources, has underscored the critical significance of global sustainability. Urban farming has been recognized as a promising solution to address these challenges. Despite the growing popularity of urban agriculture, there is a lack of research on how the built environment and urban micro-climates impact plant growth and food crops cultivated in cities. Our study aims to address this gap in knowledge by investigating how urban climates impact the growth and quality of 'Mosco' chili peppers, a significant crop in the Southwest United States. Peppers were cultivated in four different locations at the CSU Spur research facility in Denver, Colorado, including a ground-level plot, two rooftop areas with varying sunlight exposure, and a rooftop site under a solar panel array. Throughout the growing season, climate data and plant growth metrics were consistently monitored. Post-harvest, we characterized the biomolecular composition of the peppers using standardized methods from the Periodic Table of Food Initiative (PTFI). Collectively, the results of this study offer valuable insights into the impact of urban environments to the production and quality of peppers, informing sustainable urban farming practices and enhancing our understanding of plant adaptability in city settings.
Speakers
KB

Kathryn Braun

Colorado State University
Co-authors
EG

Eliza Gross

Colorado State University
NA
JB

Jennifer Bousselot PhD

Colorado State University
NA
JP

Jessica Prenni PhD

Colorado State University
NA
Tuesday September 24, 2024 1:50pm - 2:00pm HST
South Pacific 3

1:59pm HST

Citrus Crops 1 (CITR 1)
Tuesday September 24, 2024 1:59pm - 4:00pm HST
Comparing Scion and Rootstock Trunk Injection of Oxytetracycline for HLB Management Across Diverse Rootstocks in Florida - Larissa Nunes da Silva
Evaluation of Different Oxytetracycline Rates Delivery by Trunk Injections on Mature Valencia Sweet Orange Trees - Gabriel de Castro Marconi Pugina
Field Performance of Novel Citrus Rootstocks Grafted with Valencia and Their Response to Systemic Delivery of Oxytetracycline - Caroline de Favari Tardivo
Florida-grown 'Hamlin' Sweet Orange Failed to Produce Adequate Pounds-solids Despite Budline, Environment, and Antibiotic Treatment - John Chater
Hedging, Thinning, Controlled Release Fertilizer, and Oxytetracycline Trunk Injections to Mitigate Fruit Disorder Incidence in HLB-Affected 'Sugar Belle' Mandarin - Joe Volpe
Grove First: A Framework to Find Citrus Greening Treatments that are Safe, Affordable, and Available.- Guilherme Locatelli
Can We Improve Growth and Production in HLB- Affected Citrus Trees Using Plant Growth Regulators? - Prudhvi Vulchi
Methyl Salicylate and Gibberellic Acid For The Rehabilitation Of HLB- Affected Sweet Oranges. - Gurleen Kaur
Moderator
avatar for Caroline de Favari Tardivo

Caroline de Favari Tardivo

PhD Candidate, University of Florida
Tuesday September 24, 2024 1:59pm - 4:00pm HST
South Pacific 4

2:00pm HST

UG 1 - Growth and Physiology of Three Buckwheat Cultivars under Reduced Substrate Water Contents
Tuesday September 24, 2024 2:00pm - 2:10pm HST
Instances of water scarcity attributed to insufficient precipitation have amplified across the western United States (U.S.), leading to restrictions on ornamental plant irrigation. Fagopyrum esculentum (buckwheat) is widely used in pollinator-friendly U.S gardens due to its ornamental value and significance to pollinators. However, buckwheat's drought tolerance has not been widely investigated. The objectives of this research are to determine the effects of substrate volumetric water content on the visual quality, growth, and physiology of F. esculentum (common buckwheat), F. esculentum ‘Rose Red Soba’ and F. esculentum ‘Takane Ruby’. Cultivars were grown in an electromagnetic sensor-based automated irrigation system at substrate volumetric water content of 0.10 m3·m-3 (drought) and 0.40 m3·m-3 (control) for 35 days in a greenhouse. Plant growth index [(height (width 1 width 2)/2)/2], proportion of visibly wilted leaves, and the number of flowers were recorded weekly throughout the experiment. Gas exchange parameters were recorded at the termination of the experiment. Decreased substrate volumetric water content increased the number of visibly wilted leaves on three buckwheat cultivars. The plant growth index and number of flowers also declined as substrate volumetric water contents decreased from 0.40 to 0.10 m3·m-3. Alternatively, 'Rose Red Soba' and common Buckwheat exhibited a lower net photosynthesis rate in decreased substrate volumetric water content. Drought treatment also led to decreased stomatal conductance among all three buckwheat cultivars. Our results indicate that drought could impair buckwheat's ornamental value and growth due to the increased accumulation of visibly wilted leaves and decreases in plant growth index. Additionally, buckwheat's ability to attract pollinators could decline under drought conditions due to the loss of flower abundance. Nevertheless, 'Takane Ruby' buckwheat could maintain a higher capability of drought tolerance compared with 'Rose Red Soba' and common Buckwheat due to its capacity to maintain photosynthesis rate when substrate volumetric water content decreases.
Speakers
avatar for Sawyer Zook

Sawyer Zook

Undergraduate Researcher, University of Wyoming
I am currently an Assistant Researcher and A EPSCoR NASA fellow at the University of Wyoming. I bring a diverse range of experience from various roles related to Agriculture Research, Oil seed proccesing, Water/Wastewater Treatment, Plumbing, Welding. As well as an Organization Leadership/Horticulture... Read More →
Co-authors
DA

David Alan Claypool

University of Wyoming
NA
JC

Ji-Jhong Chen

University of Wyoming
NA
RJ

Randa Jabbour

University of Wyoming
NA
Tuesday September 24, 2024 2:00pm - 2:10pm HST
South Pacific 3

2:00pm HST

CITR 1 - Comparing Scion and Rootstock Trunk Injection of Oxytetracycline for HLB Management Across Diverse Rootstocks in Florida
Tuesday September 24, 2024 2:00pm - 2:15pm HST
The huanglongbing (HLB) associated pathogen Candidatus Liberibacter asiaticus (CLas) inhabits the phloem of infected citrus trees, which impedes the efficacy of foliar-applied chemicals for management of the disease. Trunk injection is an alternate method that allows the targeted delivery of agrochemicals into the vasculature, resulting in their systematic distribution throughout the tree. This study aims to determine the large-scale efficacy of trunk injection of oxytetracycline (OTC) on citrus tree health, fruit quality, and yield in existing rootstock trials in a commercial production site in Florida. The study compares 9-year-old Valencia sweet orange (Citrus sinensis) trees grafted on six different rootstocks in a large field trial in Polk County, Florida. The experimental design is a complete randomized block design, with three injection treatments: 1) no injection (control), 2) injection into the scion trunk, and 3) injection into the rootstock trunk. The injections were performed in May 2023, and injected trees received a commercial formulation of OTC at a rate of 1.1 g per tree using FlexInject injectors. Data collection included HLB status, tree size, yield, fruit/juice quality, fibrous root density, and leaf macro- and micronutrient content once a year, wound phenotype every six months, and bacterial titers before injection and 3 days, 1 week, and 1 month after injection. OTC injections into the scion or the rootstock trunk improved tree health, yield, fruit/juice quality, and the leaf Ca content. Overall, injections increased fruit yield by 24% and juice brix by 9%, increasing the revenue by 36% on a per acre basis. Injection into the scion trunk was slightly superior in terms of tree growth and fibrous root density, while injection into the rootstock trunk reduced the wound size, bark cracking, and HLB symptoms. CLas titers were reduced regardless of the injection site one month after injections. In conclusion, our results suggest that OTC injections have the potential for short-term management of HLB to help with the recovery of the Florida citrus industry in the face of endemic disease conditions. The trial will continue to assess longer-term effects.
Speakers
LN

Larissa Nunes da Silva

UF/IFAS - Southwest Florida Research
Co-authors
BP

Brandon Page

Citrus Research and Development Foundation
NA
UA

Ute Albrecth

UF/IFAS - Southwest Florida Research
NA
Tuesday September 24, 2024 2:00pm - 2:15pm HST
South Pacific 4

2:00pm HST

VCM 1 - Using the Feekes Growth Stage Scale to Predict the Carbon to Nitrogen Ratio of Cereal Cover Crops
Tuesday September 24, 2024 2:00pm - 2:15pm HST
Cereals and other non-legume cover crops can help vegetable farms to reduce nitrogen leaching to ground water during rainy winter periods. A cover crop’s carbon to nitrogen ratio is an important metric that can help farmers better understand the nitrogen release dynamics from soil-incorporated cover crops. Cover crops with a lower C:N ratio (15:1) typically mineralize nitrogen when they are incorporated into the soil, whereas those with a higher C:N (25:1) usually immobilize nitrogen. But farmers need simple, reliable, field-based methods to predict a cover crop’s C:N ratio. Therefore, we evaluated the relationship between the Feekes growth stage scale and the C:N ratio of rye (Secale cereale L., ‘cv. Merced’) and triticale (X Triticosecale Wittmack, cv. ‘Pacheco’) cover crops in the Central Coast region of California. Over a hundred field samples of rye and triticale shoots were collected at various developmental growth stages from organic and conventional vegetable farms and planting date trials, across multiple soil types, planting times, row spacings, and plant densities. The Feekes scale was correlated with the C:N ratio of cover crop shoots of rye (r2=0.63) and triticale (r2=0.76). The transition from Feekes 9 (when the ligule of the flag leaf is visible) to Feekes 10 (‘boot’ stage) is roughly when the C:N ratio went from below to above 20:1. Regression plots were developed that illustrate the relationship between the Feekes scale and the C:N ratio. These results have practical implications for a new ground water protection regulation (Ag. Order 4.0) in California’s central coast region that incentivizes winter cover crops that are grown until the C:N ratio is 20:1 or more.
Speakers Co-authors
RS

Richard Smith

University of California Cooperative Extension
NA
Tuesday September 24, 2024 2:00pm - 2:15pm HST
Kahili

2:00pm HST

Why not us? Why you should attend the Department of Horticultural Science at NCSU for graduate studies
Tuesday September 24, 2024 2:00pm - 2:30pm HST
The Department of Horticultural Science at North Carolina State University is located in Raleigh, NC. The program has 3 graduate degrees, MHS (non thesis and optional DE), MS (thesis) and PhD (dissertation). Studies range from landscape design, production, sustainable agriculture, herbicide and weed science, plant physiology, breeding, molecular biology and biotechnology, and genomics. Research is conducted in modern labs, excellent controlled environment and greenhouse facilities, and 18 field research stations across the state. Thirty-one graduate faculty are located on campus and at off campus research sites. We currently have 60 graduate students in the 3 programs. The department has a number of graduate assistants available each year that provide the student with a stipend and pay for the tuition. Raleigh is located in the center of the state with easy access to highways, an international airport, many parks and greenways, and is just a short drive to the mountains and the beach. Raleigh is a cosmopolitan city and is one corner of the Research Triangle Park, a community of numerous universities, colleges, and biotech research companies.
Speakers
avatar for Gina Fernandez

Gina Fernandez

North Carolina State University
NA
Tuesday September 24, 2024 2:00pm - 2:30pm HST
Coral 5

2:00pm HST

Consumer Horticulture Master Gardener Public Interest Group Meeting
Tuesday September 24, 2024 2:00pm - 3:30pm HST
Moderator
KL

Kristine Lang

South Dakota State University
Tuesday September 24, 2024 2:00pm - 3:30pm HST
Sea Pearl 3

2:00pm HST

Interest Group Session: Speed Networking: Making Collaboration Easy
Tuesday September 24, 2024 2:00pm - 4:00pm HST
Meeting new people is one of the best ways to start collaborating. It can be difficult to meet new people even at the annual conference with so many disciplines represented. This  session /event will provide the following impacts:
  • Enhance and develop connections of ASHS members with each other.
  • Create a structured time and space for low-pressure conversations and introductions.
  • Practice elevator speeches and first impressions for aspiring and experienced professionals.
  • Increase potential collaborations across disciplines and ASHS members.
The goal of this session is for participants to meet 10 to 15 people at the conference in a fast but low-pressure time.
 
The Partnership Development Committee (PDC) will create a signup sheet for the event to gauge the number of participants so that the room can best be set along with the time each pair has to converse. All members are welcome, even those who did not sign up prior to the conference. 
We will promote this event via social media, the ASHS newsletter, and by members of the PDC personally reaching out to other ASHS Professional Interest Groups. Participants will be encouraged to bring business cards, resumes, CVs, and job opportunities to this event.
  1. Introduction (10-15 minutes)
    1. Establish groundwork for the networking event.
    2. Provide tips and potential questions for participants to ask.
  2. Networking session 1 (30 to 35 minutes)
    1. Split into two groups.
    2. Pairs have 6-7 minutes (will determine based on # of participants).
    3. 1 person from each pair will stand up and move to the next chair at the end of the designated time.
  3. Break (10-15 minutes)
    1. Opportunity for participants to talk more with someone they connected with.
  4. Networking session 2 (30 to 35 minutes)
    1. Moving sets from Groups 1 and 2 swap.
    2. Pairs have 6-7 minutes (will determine based on # of participants).
    3. 1 person from each pair will stand up and move to the next chair at the end of the designated time.
  5. Recap and discussion (15-30 minutes)
    1. Sharing opportunity for participants.
    2. Promotion of the collaboration center and other collaborative events.
    3. Opportunity for participants to talk more with someone they connected with.
The amount of time each pair has to discuss will depend on the number of participants and will be determined shortly before the session.


Moderator
Tuesday September 24, 2024 2:00pm - 4:00pm HST
Coral 1

2:14pm HST

Viticulture and Small Fruits 1 (VSF 1)
Tuesday September 24, 2024 2:14pm - 3:30pm HST
Prospects for Grapes in High Tunnels - Paul Read
Growing Grapes on the Texas High Plains: A Review of Grower Concerns and Recent Research - Thayne Montague
Improving the Climate Resilience of Wine Grape Vineyards via Trellis Selection and Applied Water Amounts in Warm/Hot Viticultural Regions - Runze Yu
Heat Stress Effects on South Mississippi Grown Bunch Grapes - Haley Williams
Rethinking Chill Models: The Role of Cold Hardiness, Freezing Temperatures and Daily Fluctuation on Promoting Dormancy Progression and Release - Amaya Atucha

Moderator
HW

Haley Williams

Mississippi State University
Tuesday September 24, 2024 2:14pm - 3:30pm HST
Nautilus 1

2:14pm HST

Hemp Research and Extension 1 (HEMP 1)
Tuesday September 24, 2024 2:14pm - 3:45pm HST
Quantitative and Qualitative Characteristics of High Quality Cannabis Sativa - Matthew Taylor
A Three-state Summary on the Critical Weed Free Period for Transplanted Floral Hemp. - Harlene HattermanValenti
Impact of Cover Crops on Weed Pressure and Soil Health in No-till Fiber Hemp Production - Ashlee George
Photoperiod Sensitive CBD Hemp Response to Fertigation Nitrogen Inputs in a Raised-bed Plasticulture Growing System - Francesco Di Gioia
Heavy Metal Application Timing Impacts Plant Growth in Cannabis sativa - Harrison Meekins
Field Evaluation of Controlled Release Fertilizer in Support of Best Management Practices for Industrial Hemp in Florida - Shea Keene
Moderator
MT

Matthew Taylor

Curio Wellness
Tuesday September 24, 2024 2:14pm - 3:45pm HST
South Pacific 1

2:14pm HST

Postharvest 1 (PH 1)
Tuesday September 24, 2024 2:14pm - 4:00pm HST
Ethylene Degreening: A Technique to Enhance Peel Color of Georgia-Grown Satsuma (Citrus reticulata) Citrus Fruit - Taiwo Owolanke
Postharvest Storage Temperatures to Promote Anthocyanin Accumulation and Antioxidant Activity in Blood Orange cv. Moro - Fariborz Habibi
Preserving Flavor in Grapefruit Juice: Continuous Flow High-Pressure Homogenization Versus Conventional Treatment - Jayashan Adhikari
Effects of Alternative Atmosphere Storage on the Postharvest Quality of Georgia-grown Blackberries - Ramsey Corn
Examining the Effect of Storage Temperatures on Chilling Injury Incidence of Georgia-Grown Peaches - Orestis Giannopoulos
Postharvest melatonin application maintains quality of jackfruit bulbs by alleviating enzymatic browning and oxidative stress under low temperature storage - Jashanpreet Kaur
Catalysis of 1-Methylcyclopropene Degradation By Non-Target Materials: Metals and Metal Salts - Ozge Horzum


Moderator
TO

Taiwo Owolanke

Graduate Research Assistant, University of Georgia
Tuesday September 24, 2024 2:14pm - 4:00pm HST
South Pacific 2

2:15pm HST

CITR 1 - Evaluation of Different Oxytetracycline Rates Delivery by Trunk Injections on Mature Valencia Sweet Orange Trees
Tuesday September 24, 2024 2:15pm - 2:30pm HST
In Florida, Huanglongbing (HLB), also known as citrus greening, has severely impacted citrus production, prompting research into alternative treatment methods such as trunk injection of oxytetracycline (OTC) to manage Candidatus Liberibacter asiaticus (CLas) colonization. This study aims to 1) determine the optimal OTC rate administered by injection to improve the health and productivity of HLB-affected mature sweet orange trees and 2) determine the impact of spring versus late summer injections to maximize benefits and the potential for extending the harvest window. The study was initiated in 2023 in a commercial citrus production setting in Polk County, Florida. The trees were 18 years old and composed of ‘Valencia’ (Citrus sinensis) scion on Swingle (C. paradisi × Poncirus trifoliata) rootstock. Four different OTC rates (0.55 g, 0.852 g, 1.1 g, and 1.65 g active ingredient per tree) and two injection times (June and September) were compared against a control receiving no injections. The experimental design was a randomized block design with eight replications, and each replication consisted of four linear trees. A commercial formulation of OTC registered in Florida was used and administered through FlexInject injectors. A volume of 100 ml per tree was used for the 0.55-1.1 g rates and administered with one injector. The highest rate (1.65) was administered using two injectors on opposite sides of the tree in a volume of 75 ml per injector. Tree health was assessed by visual ratings of foliar HLB symptoms and canopy densities, while CLas titers were quantified using real-time PCR. Fruit quality and yield measurements included total soluble solids, titratable acidity, fruit weight, and juice characteristics. Trees were harvested, and fruit/juice quality was determined in March 2024. Overall, injected trees produced significantly more and larger fruit with better juice color, a higher percentage of juice, and more total soluble solids than control trees. The highest rate of OTC produced the highest yield and highest-quality fruits compared to the other rates. We did not observe any difference between spring (June) and summer (September) injections on any measured variables. Bacterial titers were reduced in the injected trees compared to the non-injected trees, and injected trees had fewer HLB symptoms and denser canopies than control trees. This research provides important insights into the best practices for managing HLB using trunk injection of OTC.
Speakers Co-authors
CT

Caroline Tardivo

University of Florida
UA

Ute Albrecht

University of Florida
NA
Tuesday September 24, 2024 2:15pm - 2:30pm HST
South Pacific 4

2:15pm HST

HEMP 1 - Quantitative and Qualitative Characteristics of High Quality Cannabis Sativa
Tuesday September 24, 2024 2:15pm - 2:30pm HST
Scientific research activities focused on production of high-quality Cannabis sativa continue to grow in both the industry and academic sectors. At the university level in the United States, the majority of the research uses hemp-type or low tetrahydrocannabinolic acid (THCa) cannabis cultivars due to federal restrictions. Only at the industry level and in states with some level of medical or recreational legalization can production research be carried out on high THCa or drug-type Cannabis. Dried female flower inflorescences are the harvested and saleable portion of the Cannabis plant. The quantitative traits of flowers are relatively clear and easily enumerated. To be considered superior quality, THCa concentration should be 25% or greater and the total terpene concentration should be 2% or greater on a dry weight basis (moisture content of 10-12%). While the average cannabis consumer values these characteristics, they also greatly appreciate many of the qualitative characteristics of cannabis flower, which include visual appearance or sometimes referred to as bag appeal, olfactory characteristics when opening the container of cannabis and while breaking apart the flowers, texture, and taste when smoking. These characteristics are more difficult to define and quantify. When conducting research, both quantitative and qualitative characteristics need to be of great consideration when the goal is to produce high quality Cannabis flower.
Speakers
MT

Matthew Taylor

Curio Wellness
Tuesday September 24, 2024 2:15pm - 2:30pm HST
South Pacific 1

2:15pm HST

PH 1 - Ethylene Degreening: A Technique to Enhance Peel Color of Georgia-Grown Satsuma (Citrus reticulata) Citrus Fruit
Tuesday September 24, 2024 2:15pm - 2:30pm HST
In recent years, the production of Satsuma oranges (Citrus reticulata) has significantly increased in the state of Georgia. Satsumas are known to develop a deep orange peel color naturally when the temperature drops below 12°C at night. However, due to the subtropical climate of South Georgia, the fruit often fails to turn orange naturally even after attaining physiological maturity standards. Consumers tend to choose fruits based on appearance, with brightly colored oranges being more likely to attract buyers. Degreening is a postharvest technique that utilizes gaseous ethylene (C2H4) to accelerate and promote the development of orange/yellow color pigments in fresh-market citrus fruit. The study was conducted using four Satsuma cultivars ('Brown Select', 'Owari', 'Miho', and 'Xie Shan') harvested at physiological maturity yet with green peel coloration. The fruit samples were subjected to a degreening treatment which involved exposure to a continuous flow of
Speakers
TO

Taiwo Owolanke

Graduate Research Assistant, University of Georgia
Co-authors
AD

Angelos Deltsidis

University of Georgia
AB

Anthony Bateman

University of Georgia
NA
JP

Jake Price

University of Georgia, Extension
NA
OG

Orestis Giannopoulos

University of Georgia
RC

Ramsey Corn

University of Georgia
Tuesday September 24, 2024 2:15pm - 2:30pm HST
South Pacific 2

2:15pm HST

VCM 1 - Associations Among Crop/Weed Management Practices and Environmental Factors Highlight Challenges Facing U.S. Snap Bean Production
Tuesday September 24, 2024 2:15pm - 2:30pm HST
Snap bean production has decreased by ~30% recently due to an increase in imports and changing consumer preferences towards more fresh and frozen products. A major production concern is weed species that escape control, since they cause yield losses and can contaminate harvest loads. Coupled with changing weather patterns, snap bean processors and growers will have to adjust to these and future challenges. Field surveys were conducted to identify associations among crop/weed management practices and environmental factors on snap bean yield and weed density. From 2019-2023, snap bean fields throughout the major U.S. production regions were surveyed for weeds at harvest. Management records for each field were obtained from growers. Information on soil and weather conditions of each surveyed field also was obtained. In total 358 production fields were surveyed in the Midwest (Illinois, Iowa, Minnesota, Wisconsin), Northeast (Delaware, Maryland, New York. Pennsylvania), and Northwest (Oregon, Washington) regions. To determine associations among management and environmental variables on crop yield and weed density, the machine learning algorithm random forest was utilized. The models had 24 and 22 predictor variables for crop yield and weed density, respectively, and both were trained on 80% of the data with the remainder used as a test set to determine model accuracy. Partial dependence plots were used to visualize the change in response variables based on the most important predictors. The crop yield model had pseudo-R2 values of 0.56 and an accuracy of 74%. Higher average temperatures during early season growth, higher soil organic matter content, and planting midseason (June-July) predicted an increase in average crop yield. Meanwhile, excessive precipitation early in the season, high sand content of the soil, high temperatures at crop flowering and row cultivation predicted a decrease in crop yield. The weed density model had pseudo-R2 values of 0.55 and an accuracy of 81%. While row cultivation was associated with lower snap bean yield, it corresponded to a decrease in weed density, suggesting row cultivation had less-than-ideal selectivity between the crop and weed. Moreover, multiple spring tillage operations prior to planting predicted an increase in average weed density, implying that excessive tillage may favor emergence of weeds in snap bean. Over the coming decades, climate change-driven weather variability is likely to influence snap bean production, both directly through crop growth and indirectly through weeds that escape control practices that also are influenced by the weather.
Speakers Co-authors
BS

Barbara Scott

University of Delaware
NA
CL

Carolyn Lowry

Penn State University
NA
EP

Edward Peachey

Oregon State University
NA
JC

Jed Colquhoun

University of Wisconsin
LS

Lynn Sosnoskie

Cornell University
NA
MV

Mark VanGessel

University of Delaware
NA
NK

Nicholas Korres

University of Ioannina
NA
PP

Pavle Pavlovic

University of Illinois Urbana-Champaign
NA
RL

Rui Liu

Washington State University
Tuesday September 24, 2024 2:15pm - 2:30pm HST
Kahili

2:15pm HST

VSF 1 - Prospects for Grapes in High Tunnels
Tuesday September 24, 2024 2:15pm - 2:30pm HST
High tunnels have proven to be a suitable alternative for a number of small fruits and vegetables, but potential applications for grapes need to be further explored. We have conducted seven years of research with table grapes in high tunnels and demonstrated that profitable production can be achieved with the concomitant reduction of environmental challenges, including vertebrate pests, hail and extremes of weather. This approach has also resulted in less pesticides required to maintain a quality robust canopy. Furthermore, our research has shown that cold storage retains marketable quality, thus enabling extending the marketing season for the cultivars tested (Thomcord, Everest, Marquis, Mars, Canadice and Somerset). In addition, we have explored the potential of growing Vitis vinifera grapes in a high tunnel in the Midwest with the goals of enabling our commercial wineries to have a local source of grapes that are not adapted to field production in Nebraska but are desired by consumers. Vinifera grapes can thus be produced as a local wine varietal or can be employed to enrich wines made from locally adapted cultivars. Data on survival and productivity of specific cultivars such as Cabernet Sauvignon, Tannat, Petit Verdot, Riesling and other vinifera cultivars will be presented while discussing the productivity of closely related new cultivars.
Speakers
PR

Paul Read

University of Nebraska
Tuesday September 24, 2024 2:15pm - 2:30pm HST
Nautilus 1

2:15pm HST

Interest Group Session: Understanding Labor Constraints and Opportunities, and Behavioral, Economic, Engineering, and Production Influences on Automation Adoption in the Green Industry
Tuesday September 24, 2024 2:15pm - 4:15pm HST
In the this session, the Nursery LEAP (Labor, Engineering, Automation, and Production) Team will present results culminating from a USDA SCRI planning grant survey and related topics. The team will describe current labor challenges, limitations of the current workforce, and opportunities through multiple visa programs. Team members will also present the correlation between perceived barriers to adoption, nursery business characteristics, and the likelihood of adopting automated technologies; nursery producers’ perceptions and intent to use automated nursery technologies; and an overview of current mechanization and automation levels in nurseries. Founders of Moss Robotics, Inc. will share their approach to developing and commercializing AI, computer vision, and machine-learning-based technology for the nursery industry. The session will conclude with a facilitated panel discussion featuring all speakers.
Coordinator(s)
  • Jacob Shreckhise, USDA-ARS, U.S. National Arboretum, McMinnville, Tennessee, United States
  • Amy Fulcher, University of Tennessee, Plant Sciences, United States
  • Anthony LeBude, NC State University, United States
  • James Altland, USDA-ARS, Wooster, OH, United States
Moderator(s)
  • Natalie Bumgarner, University of Tennessee, United States
Speaker/Participant(s)
  • Anthony LeBude, NC State, United States
    The Nursery Industry’s Labor Dilemma (10 mins)
    Summary: Dr. Anthony LeBude, NC State University, will provide an overview of the US nursery industry’s labor challenges and the threat that these challenges pose to the sustainability of this labor-reliant industry.
  • Margarita Velandia, University of Tennessee, Knoxville, Knoxville, Tennessee, United States
    The Role of U.S. Temporary Foreign Worker Visa Program in Addressing the Green Industry Labor Needs: Challenges and Opportunities (20 mins)
    Summary: In this presentation, Dr. Margarita Velandia, University of Tennessee, will give a general overview of the H-2A, H-2B, and the TN NAFTA or TN USMCA visa programs and discuss challenges and opportunities associated with each program in addressing the green industry labor needs.
  • Alicia L Rihn, University of Tennessee, Knoxville, United States
    Factors Correlated with the Propensity to Use Automation and Mechanization (20 mins)
    Summary: Several of the U.S. nursery industry’s characteristics and actions to address labor issues are correlated with the use of automated technologies. Dr. Alicia Rihn, University of Tennessee, will explore the correlation between perceived barriers of adoption, nursery business characteristics, and the likelihood of adopting automated technologies.
  • Amy Fulcher, University of Tennessee, Plant Sciences, United States
    Nursery Mechanization and Automation Adoption Levels (20 mins)
    Summary: Nursery Mechanization and Automation Adoption Levels – Dr. Amy Fulcher, University of Tennessee, will present current nursery mechanization and automation adoption levels and compare the current percentage of individual tasks that are automated with 2006 levels.
  • James Altland, USDA-ARS, Wooster, OH, United States
    Panel Discussion (10 mins)
    Summary: Dr. James Altland, USDA-ARS, will facilitate the panel session through thoughtful prompts and questions from the audience to foster enriching discussion.
  • Anthony LeBude, NC State University, will describe collaborative work led by Dr. Laura Warner, University of Florida, on using Diffusion of Innovations theory to understand growers’ perceptions of nursery technology and how these perceptions shape growers’ adoption of automation, as well as results from a Theory of Planned Behavior evaluation of nursery growers’ intent to use automation from 4 technology clusters. 
  • Di Hu and Shrijit Singh, founders of Moss Robotics, Inc., will discuss how advancements in autonomous driving and AI have unlocked new possibilities for the green industry. Moss leverages robotics, computer vision, and machine learning to revolutionize field scouting, providing nursery producers with cost-effective solutions for efficient crop management and monitoring. In this presentation Ms. Hu and Mr. Singh will explore Moss’ innovative approach, including a case study demonstrating the transformative impact of their robotic field scouting solution. 

Moderator
NB

Natalie Bumgarner

Assistant Professor, University of Tennessee Knoxville
Speakers
AF

Amy Fulcher

University of Tennessee
MV

Margarita Velandia

The University of Tennessee
NA
JS

Jacob Shreckhise

USDA-ARS, U.S. National Arboretum
DH

Di Hu

CEO, moss robotics inc.
SS

Shrijit Singh

CTO, moss
Tuesday September 24, 2024 2:15pm - 4:15pm HST
Lehua Suite

2:29pm HST

Plant Biotechnology 1 (PB 1)
Tuesday September 24, 2024 2:29pm - 4:00pm HST
Revolutionizing Grapevine Breeding: Overcoming Perennial Challenges with Genome Editing - Bridget Bolt
CRISPR/Cas9-Mediated Development of Low Mowing Frequency Perennial Ryegrass and Tall Fescue Varieties - Roshani Budhathoki
Precision Breeding Using CRISPR to Improve Production Traits in Blackberry - Pradeep Marri
Double CRISPR Knockout of Pectin Degrading Enzymes Improves Tomato Shelf-life While Ensuring Fruit Quality - Isabel Ortega Salazar
Functional Characterization of a Candidate Bacterial Wilt Resistance Gene in Tomato - James Duduit
Novel Short Synthetic Promoters for Constitutive Expression in Dicot Species - debao huang

Moderator
avatar for Isabel Ortega Salazar

Isabel Ortega Salazar

University of California, Davis
Tuesday September 24, 2024 2:29pm - 4:00pm HST
South Pacific 3

2:30pm HST

CITR 1 - Field Performance of Novel Citrus Rootstocks Grafted with Valencia and Their Response to Systemic Delivery of Oxytetracycline
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Worldwide citrus production faces significant challenges from the devastating disease Huanglongbing (HLB), necessitating innovative management strategies. This study aimed to assess the performance of novel rootstocks under natural HLB-endemic conditions using regular management practices and the recently registered practice of delivering oxytetracycline (OTC) through trunk injection to reduce pathogen load. Nine novel rootstocks, US-1673, US-1676, US-1680, US-1672, US-1687, US-1688, US-2111, US-2132, and US-2137 with different genetic backgrounds, including Citrus maxima, C. tachibana, C. reticulata, and Poncirus trifoliata were included in the study. Also included were two commercial rootstock standards, sour orange (C. aurantium) and Swingle (C. paradisi × P. trifoliata). The rootstocks were grafted with ‘Valencia’ sweet orange (C. sinensis) scion and planted in 2014 in a randomized complete block design and 12 single-tree replications in an open field in St. Lucie County, Florida. In July 2023, half of the trees were injected with ReMedium TI® (95.0% oxytetracycline hydrochloride) dissolved in reverse osmosis water acidified with muriatic acid to a pH of 2.0. Each tree received 0.75 g OTC dissolved in a volume of 75 ml (10,000 ppm) administered using FlexInject injectors. Injections were performed in the scion, approximately 5 cm above the graft union. Tree measurements included tree size, canopy health, pathogen titers, fruit yield, and juice quality. Significant differences among rootstocks were observed in the years before injection. In the 2022-2023 production season, US-1688 induced the highest yield, and US-2132 induced the best juice quality. Preliminary results indicate an overall positive response to the OTC treatment across all rootstocks. Injected trees had a 36% increase in yield, an 11% increase in juice brix, and a significant reduction in leaf and root pathogen titers. As in the previous years, growth and productivity varied significantly among the rootstock cultivars. US-1688, a new release by USDA under the name SuperSour 4, continued to be among the largest, healthiest, and most productive trees. The results from this research demonstrate the importance of rootstock selection for sustainable citrus cultivation. It also highlights the benefits of integrating the systemic delivery of antibacterial therapies to maximize the resilience of citrus trees to HLB.
Speakers
avatar for Caroline de Favari Tardivo

Caroline de Favari Tardivo

PhD Candidate, University of Florida
Co-authors
KD

Kim D Bowman

USDA ARS
NA
UA

Ute Albrecht

University of Florida
NA
Tuesday September 24, 2024 2:30pm - 2:45pm HST
South Pacific 4

2:30pm HST

HEMP 1 - A Three-state Summary on the Critical Weed Free Period for Transplanted Floral Hemp.
Tuesday September 24, 2024 2:30pm - 2:45pm HST
There is a growing demand for hemp-derived products but because of the crop's criminalization history, there is limited University-produced information describing best production practices. The research objective was to define the critical weed-free period (CWFP) for transplanted floral hemp. Field trials were conducted in 2022 and 2023 at an outlying NDSU Agriculture Experiment Station near Prosper, ND (46.57° N, 97.01° W), the Cornell AgriTech campus in Geneva (42.88°N, 77.01°W), and the Clemson University Coastal Research and Education Center (33.46°N, 79.55°W). Four cultivars were transplanted at NY with three cultivars (Bubbatonic, Sour Space Candy, and Quick Spectrum) in common with ND. Three cultivars were transplanted in SC with two cultivars (Cherry Wine and Bubbatonic) in common with NY. The CWFP treatments were weeded for 0, 1, 2, 4 and 6 weeks, and weed-free. Weeding was accomplished by manually hoeing and hand-weeding. Weed species varied at each location but were mainly annual weed species (both broadleaf and grasses). Plants were harvested after at least a 16-week period in the field and air-dried before removing leaf and floral biomass from stems. At SC, when averaged across cultivars and trial years, a significant increase in mean floral yield with 2, 4, 6, and season long weed-free intervals when compared to 0 weeks weed-free. In addition, a significant decrease in dry weed biomass existed when comparing the same weed-free intervals to the 0 weeks weed-free treatment. At NY, hemp biomass averaged across all cultivars was significantly affected by the duration of weed competition. Per plant yields were reduced >80% when weeds were allowed to compete almost season-long. Biomass production was maximized when weeds were suppressed for at least 6 weeks after transplanting. At ND, results were quite different due to timely rainfall and lack of rain. Under adequate to excellent moisture conditions, the stem diameter, stem number, plant weight:height ratio, and dry biomass yield responses were significantly different only when weed control was provided for one week. However, under extreme season long drought conditions, stem diameter increased 53%, weight:stem ratio increased 172% and dry biomass increased 201% when weeds were controlled the entire season. Results indicate that transplanted hemp is sensitive to competition and preventing weed establishment for several weeks was necessary to reduce competitive interactions. Results also suggested that the need for a weed-free period was exacerbated and most important when rainfall during the growing season was limited.
Speakers Co-authors
LS

Lynn Sosnoskie

Cornell University
NA
MC

Matthew Cutulle

Clemson University
Tuesday September 24, 2024 2:30pm - 2:45pm HST
South Pacific 1

2:30pm HST

PB 1 - Revolutionizing Grapevine Breeding: Overcoming Perennial Challenges with Genome Editing
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Climate change poses a significant threat to perennial crops like grapevine in the USA, with projections indicating that 50-81% of acreage may become unproductive by 2040. To address this, breeding resilient varieties is imperative. However, traditional breeding for perennials is time-consuming (25-30 years) due to extended evaluation periods. Genome Editing, specifically CRISPR/Cas9, offers targeted modification potential but faces hurdles in perennial crops such as grapevine. These include somaclonal variation, inefficient transformation, transgene removal needs, and industry hesitance. We propose an efficient Genome Editing method for grapevine leveraging the systemic mobility of methylated dicistronic mRNA:tRNA molecules. This approach aims to: 1. Enable genome editing without transgene integration, negating the need for backcrossing and preventing unintended genetic changes. 2. Circumvent in-vitro culture, reducing somaclonal variation risk and preserving existing chimerism. Our method addresses key challenges in Genome Editing adoption for grapevine and could accelerate the development of climate-resilient varieties, crucial for sustainable agriculture in a changing climate.
Speakers
avatar for Bridget Bolt

Bridget Bolt

Graduate Research Assistant, University of Kentucky
NA
Tuesday September 24, 2024 2:30pm - 2:45pm HST
South Pacific 3

2:30pm HST

PH 1 - Postharvest Storage Temperatures to Promote Anthocyanin Accumulation and Antioxidant Activity in Blood Orange cv. Moro
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Blood oranges (Citrus sinensis L. Osbeck) fruit contain valuable compounds for human health, including anthocyanins, flavonoids, polyphenols, hydroxycinnamic acids, and ascorbic acid. Anthocyanin is considered an important internal quality index of blood oranges due to its red color and antioxidant activity. Blood orange pigmentation under similar growing conditions depends on some factors including cultivar, cultural practices, soil characteristics, climate conditions, maturity, and harvest maturity. Blood orange fruit require cold temperatures between 8 °C to 15 °C during the last ripening stages to develop high levels of anthocyanin in their flesh. However, commercial production of blood oranges in subtropical or tropical regions is limited due to very low or lack of cold temperatures to enhance anthocyanin concentration in fruit. We evaluated the effect of different storage temperatures (10, 15, and 20 °C) on anthocyanin enhancement and the antioxidant activity of ‘Moro’ blood orange for 42 days. Fruit were harvested from a commercial citrus orchard in south Georgia and transported to the postharvest lab in Gainesville, Florida. Fruit were checked for absence of defects andr rind injuries, sanitized with 100 ppm sodium hypochlorite solution, and superficial water removed from the fruit surface. The fruit were then divided into sets of four replicates of 10 fruit per treatment and placed in mesh bags for storage at 10, 15, or 20 °C with 90 % relative humidity. Anthocyanin accumulation and antioxidant activity in the flesh were evaluated every 14 days for 42 days. There were significant differences among the applied storage temperatures for anthocyanin content and antioxidant activity. The highest anthocyanin concentration and antioxidant activity were observed at 10 °C, while the lowest anthocyanin level was at 20 °C for all sampling times. The efficiency of these temperatures in enhancing flesh anthocyanin and antioxidant activity was in the following order: 10 °C > 15 °C > 20 °C at all sampling times. Overall, it can be concluded that cold storage can be used as a simple technology for enhancing bioactive compounds and antioxidant activity in blood oranges that are poorly pigmented at harvest in subtropical or tropical climates like Florida.
Speakers
FH

Fariborz Habibi

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
JB

Jeffrey Brecht

University of Florida
NA
Tuesday September 24, 2024 2:30pm - 2:45pm HST
South Pacific 2

2:30pm HST

VCM 1 - Impact of Early Season Tarping on Soil Conditions and Weed Populations in North Central United States Vegetable Production Systems
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Weed management is one of the biggest challenges vegetable growers face. Plastic mulch, herbicides, tillage, and hand-weeding are common ways vegetable growers manage weeds. These methods can be labor intensive, require specialized equipment, and cause environmental harm. Tarping is an alternative weed management method. Silage tarps or high-tunnel plastics are commonly used tarping materials; these are multi-functional tools that can be used for several years. Tarping facilitates stale seedbed weed management techniques by modifying the soil microclimate and promoting weed germination. After weed germination, opaque tarps can terminate weeds via occultation (lack of sunlight), whereas clear tarps terminate weeds by creating extreme temperatures. More information is needed for the type and timing of early-season tarp application for optimal weed control. The research was conducted at the Iowa State University Horticulture Research Stations in Ames, IA. This study examined three types of tarps: black, white, and clear, at three different durations: two, four, and six weeks prior to planting compared to a non-tarped control. Clear tarp and control treatments were cultivated at the time of tarp removal prior to planting. Soil temperature was recorded at 5 centimeters depth for 6-week tarp treatments. Early-season clear tarping did not elevate temperatures enough to terminate the majority of weeds. However, black and white tarps created a weed-free planting bed. Average soil temperatures underneath the clear tarp were the warmest (21.8ºC), followed by black tarp (15.1ºC). White tarp treatments (11.7ºC) had a lower average soil temperature than treatments with no tarp (14.8ºC). Two weeks following tarp removal, six-week clear tarp treatments had a higher percent weed cover than black and white tarp treatments measured using Turf Analyzer, a digital photo analysis software. Differing soil temperatures did not significantly impact soil microbial biomass carbon. The two-week white tarp had significantly higher soil microbial biomass nitrogen than all other treatments except four-week clear tarp. There was no effect of tarp type or duration on onion crop yield. These results indicate that the use of white and black tarps can be a feasible alternative weed management method in North Central vegetable production systems.
Speakers
avatar for Carly Strauser

Carly Strauser

Iowa State University
Graduate Research Assistant, Department of Horticulture at Iowa State University
Co-authors
AN

Ajay Nair

Iowa State University
NA
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Kahili

2:30pm HST

VSF 1 - Growing Grapes on the Texas High Plains: A Review of Grower Concerns and Recent Research
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Within the State of Texas the grape (Vitis vinifera) and wine industry has an economic impact of over $20 billion. Currently there are more than 3,700 ha of vineyards within the state, and greater than 80% of Texas vineyards are within the Texas High Plains American Viticultural Area (AVA). High Plains AVA grape growers are blessed with beneficial soil conditions, low biotic stress factors, and a generally favorable climate. However, geophysical challenges within the AVA include dangerous winter temperature extremes, late spring frosts, high wind speed events, thunderstorms, damaging hail, drought, and herbicide volatility and drift concerns. Despite these challenges, the Texas High Plains AVA has gained a reputation for producing high yields and fruit with exceptional quality. This presentation will focus on recent (past three years) research efforts performed by Texas A&M AgriLife Research and Extension and Texas Tech University personnel: investigating grape grower concerns associated with vine water requirements, avoiding grapevine hail damage, estimating vine cultivar bud dormancy traits, and quantifying herbicide drift and volatilization into vineyards. Presented research results benefit Texas High Plains grape growers and give growers additional insight into production practices and management methods suited for grape production within the unique Texas High Plains AVA environment.
Speakers
avatar for Thayne Montague

Thayne Montague

Professor, Texas Tech University / Texas A&M AgriLife Research
Dr. Thayne Montague received his Ph.D. in Horticulture Plant Physiology from Utah State University, and is employed by Texas Tech University Department of Plant and Soil Science and Texas A&M AgriLife Research. Dr. Montague's teaching responsibilities include Plant Propagation, Woody... Read More →
Co-authors
Tuesday September 24, 2024 2:30pm - 2:45pm HST
Nautilus 1

2:45pm HST

CITR 1 - Florida-grown 'Hamlin' Sweet Orange Failed to Produce Adequate Pounds-solids Despite Budline, Environment, and Antibiotic Treatment
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Huanglongbing (HLB) is a devastating bacterial disease in Florida and has been spreading in citrus-growing regions in Texas, Georgia, and California. HLB threatens the entire US fresh and processed citrus industries. To date, all commercial sweet orange (Citrus sinensis L. Osbeck) cultivars are susceptible, though some are more tolerant than others. The citrus industry has an estimated economic impact nationwide of over $13 billion. The currently applied strategies for mitigating this disease are costly and unsustainable. The development and commercialization of HLB tolerant sweet orange scions is needed for sustainable and profitable citriculture in the US. Citrus Under Protected Screen (CUPS) is a method used in Florida to exclude the Asian Citrus Psyllid (Diaphorina citri Kuwayama, or ACP), which is a phloem-feeding hemipteran insect that is the vector for Candidatus Liberibacter asiaticus CLas the causal agent believed to be responsible for HLB disease in citrus. ‘Hamlin’ sweet orange is the most important early sweet orange for processing in modern history. ‘Hamlin’ has a budline called ‘Hamlin 1-4-1’, which is the predominant budline in the State of Florida. ‘Hamlin 1-4-1’ has high susceptibility to HLB, which causes symptoms such as blotchy mottle, small fruit size, high titratable acidity (TA), low total soluble solids (TSS), and severe fruit drop. ‘Hamlin N13-32’ is a new budline of ‘Hamlin’ sweet orange that appears to have enhanced tolerance to HLB in terms of tree health. ‘Hamlin 1-4-1’ and ‘Hamlin N13-32’ trees were followed for two years in multiple environments with and without treatments of oxytetracycline. Tree size, rootstock, fruit number, fruit size, TSS, TA, TSS:TA ratio, and pounds-solids data were collected to determine the effects of environment (CUPS versus outside grove), antibiotic treatment effects, and budline effects on production. There were some significant differences among groups for fruit quality, but more research is needed to determine effects of oxytetracycline, budline, rootstock and environment on ‘Hamlin’ sweet orange production.
Speakers
JC

John Chater

University of Florida
Tuesday September 24, 2024 2:45pm - 3:00pm HST
South Pacific 4

2:45pm HST

HEMP 1 - Impact of Cover Crops on Weed Pressure and Soil Health in No-till Fiber Hemp Production
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Current fiber hemp (Cannabis sativa <0.30% total THC) production systems rely on pre-emergent herbicides to manage weeds prior to canopy closure. Due to the rapid growth of fiber hemp, paired with the plastic nature of the crop, the need for weed suppression is most critical in the first month after planting. No-till systems with a rolled cover crop residue may be able to provide weed suppression without the use of herbicides, which can lower the cost of inputs, reduce the risk of negative environmental impacts associated with herbicide use, and improve soil health. Four cover crops - crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa), cereal rye (Secale cereale), and triticale (xTriticale)- were roller-crimped into a mulch, and fiber hemp was no-till drilled into the residue. Each cover crop plot was paired with two bare ground plots, one of which was weeded weekly, while the other remained weedy. This design was repeated in three locations in the coastal-plain region of North Carolina (Kinston, Clinton, and Goldsboro). Crop emergence, weed counts and biomass, and fiber hemp biomass and yield were measured in each plot. Cover crop biomass was measured before planting and after retting to determine whether this residue may be a potential contaminant during baling. Soil health parameters were compared among cover and bare plots. Hairy vetch resulted in greater hemp emergence in Kinston, but emergence was not affected by the mulches otherwise. Hairy vetch plots had less weeds than others in Clinton and Goldsboro. Soil respiration and potentially oxidizable carbon did not differ by treatment, with the exception of higher soil respiration in grass covers in Goldsboro. Cover crop biomass remaining after retting was higher in grass plots than legume plots, indicating a potential for bail contamination. These preliminary results indicate that fiber hemp can be grown in a no-till system.
Speakers
AG

Ashlee George

Graduate Student, North Carolina State University
Co-authors
AW

Alex Woodley

North Carolina State University
NA
DS

David Suchoff

North Carolina State University
NA
SH

Shannon Henriquez Inoa

North Carolina State University
NA
Tuesday September 24, 2024 2:45pm - 3:00pm HST
South Pacific 1

2:45pm HST

PB 1 - CRISPR/Cas9-Mediated Development of Low Mowing Frequency Perennial Ryegrass and Tall Fescue Varieties
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Tall fescue (Lolium arundinacea Schreb.) and perennial ryegrass (Lolium perenne) are common cool-season turfgrass species. They are widely utilized in home lawns, athletic fields, golf courses, and roadsides. However, these grasses require frequent mowing to maintain lawn quality. Developing low-mowing frequency varieties is highly desirable because it can significantly reduce maintenance costs and fuel consumption. Gibberellin 20-oxidases (GA20ox) are key genes in the gibberellic acid (GA) biosynthesis pathway, mutations in which can induce a dwarf phenotype in plants and, therefore, reduce mowing frequency, as demonstrated by our dwarf turf varieties developed using conventional mutagenesis techniques. We have recently employed CRISPR/Cas9 technology to create knockout or knockdown mutations in the GA20oxidase1 gene to develop dwarf tall fescue and perennial ryegrass lines. The CRISPR/Cas9 construct used for editing LaGA20ox1 and LpGA20ox1 has ZmUbi and OsU6a promoters controlling the expression of Cas9 and sgRNA, respectively. We have delivered the CRISPR/Cas9 construct into tall fescue and perennial ryegrass via Agrobacterium-mediated transformation. We have observed a 35-50% reduction in plant height compared to the parental wild-type plants. Furthermore, the leaf widths in these mutants are reduced by 30-60%. Some mutants display a smoother leaf texture compared to the wild type. The T2 homozygous mutant progenies will undergo field evaluation for mowing frequency and fertilizer requirements. We anticipate that some of these gene-edited lines should exhibit a significant reduction in mowing frequency and fertilizer input.
Speakers
RB

Roshani Budhathoki

University of Connecticut
Tuesday September 24, 2024 2:45pm - 3:00pm HST
South Pacific 3

2:45pm HST

PH 1 - Preserving Flavor in Grapefruit Juice: Continuous Flow High-Pressure Homogenization Versus Conventional Treatment
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Grapefruit is known for its citrus aroma and tangy flavor. Processors use post-harvest preservation methods for juice production to maintain quality during storage for market distribution. These processes aim to preserve quality and safety while reducing unwanted compounds such as furanocoumarins. However, traditional methods like thermal pasteurization alter sensory quality and nutrient contents. With consumers demanding fresh-like taste without safety issues, researchers have aimed to develop new processing technologies. Here, we tested continuous flow high-pressure homogenization (CFHPH) for grapefruit juice processing. This method may extend shelf-life while maintaining fresh-like flavor. In this study, CFHPH was applied at various pressure levels (200, 250, 300 MPa), inlet temperatures (4 or 22 °C), and a flow rate of 1.125 L/min, and compared with conventional high-temperature short time (HTST) processing for preserving flavor compounds in Ruby Red grapefruit juice during storage at 4 °C for 45 days. Gas chromatography–mass spectrometry analysis identified key volatile compounds such as limonene, myrcene, α-pinene, β-pinene, and linalool. CFHPH preserved flavor compounds better than HTST, while HTST treatments led to flavor loss and off-notes. CFHPH maintained major volatiles like limonene, suggesting its potential as a consumer-preferred preservation method. This research underscores the significance of innovative techniques for maintaining grapefruit juice sensory quality, which is essential for customer satisfaction and market success.
Speakers Co-authors
KA

Koushik Adhikari

University of Georgia
NA
RS

Rakesh Singh

University of Georgia
NA
Tuesday September 24, 2024 2:45pm - 3:00pm HST
South Pacific 2

2:45pm HST

VCM 1 - Applying Advanced Lighting Practices for Vegetable Propagation
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Propagation greenhouses produce a wide range of crops, each presenting unique responses to light quality and quantity. With dynamic LED lighting solutions now available and proven to be viable over large acreages, propagators can tailor their lighting protocols to each crop with regards to zone management, photoperiod, spectrum and intensity. The effects of light quality and quantity on plant morphology and growth are well documented and while the exact impact is not generalizable across all crops and varieties, certain themes hold true. For example, high levels of blue light are generally associated with compact plants and thick, waxy leaves. In contrast, high levels of far-red light can cause etiolation in multiple species through the shade avoidance response but enhances photosynthesis and growth when combined with red light. Given the high importance of crop morphology in propagation, dynamic Dynamic LED lighting has been used to develop advanced lighting protocols in the propagation of fruit, vegetable and ornamental crops. In the production of cucumber transplants, applying high levels of blue light and a long photoperiod effectively slows the growth of cucumber transplants at the end of the propagation cycle, a strategy which proved useful to a propagator looking to delay transplant delivery per the client’s request. Concretely, the combination of high blue levels and a long photoperiod slowed crop growth, prevented tendril development and restricted plant stretching. Further, the use of high-blue treatments over young leafy greens effectively reduced plant height by 2-3 cm and produced stronger plants. Another trial focused on the production of strawberry tray plants found that a balanced light spectrum produced more stolons (i.e., daughter plants) while a blue-enriched spectrum produced significantly more leaves. In the production of ornamentals, dynamic lighting can be used to reduce the greenhouse’s reliance on plant growth regulators (PGRs), enhance leaf or petal coloration and trigger bud formation. In red-leafed varieties, controlled light-induced plant stress through spectral and/intensity adjustments have proven effective at stimulating the production of red pigments and enriching the leaves’ hue. Results from various commercial and research trials demonstrate benefits of dynamic LED lighting in the propagation of horticultural and ornamental crops alike. This presentation presents data from the aforementioned case studies among others.
Speakers
RS

Rose Seguin

Agronomist, Sollum Technologies
Rose Séguin is an agronomist specializing in controlled environment agriculture, with previous experience in indoor agriculture, agricultural innovation systems, and agricultural development in remote areas of Canada. She holds a bachelor's degree in agro-environmental sciences and... Read More →
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Kahili

2:45pm HST

VSF 1 - Improving the Climate Resilience of Wine Grape Vineyards via Trellis Selection and Applied Water Amounts in Warm/Hot Viticultural Regions
Tuesday September 24, 2024 2:45pm - 3:00pm HST
In grape vineyards, trellis systems are used to provide specific canopy microclimate to optimize grapevine production, physiological performance, and berry composition. However, many major wine producing regions are being challenged by the constantly increasing air temperature and decreasing available water allocated for agricultural use. The objective of this study was to understand the impact of trellis system and applied water amount on grapevine productivity and grape quality. This study was conducted to evaluate six trellis systems, including a vertical shoot positioned (VSP), two modified VSP systems (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a cane-pruned VSP-Guyot (GY) and three applied water amounts based on various crop evapotranspiration (ETc), including 25%, 50%, and 100%, in 2020 and 2021. The results showed that SH and HQ systems, once fully established, could have higher efficiency in accumulating total soluble solids (TSS) and total yield. Also, these two systems showed greater flavonol and anthocyanin accumulation in grape berry skins compared to the VSPs, possibly resulted from reduced chemical degradation from the hotter environment Being strongly correlated with canopy architecture, the flavonols and molar percentage of quercetin in berry skins, indicated that the VSP systems were more likely to be prone to overexposure and potential photooxidative stress. The three applied water amounts showed that with less water, grapevines would have lowered yield but increased berry flavonoid accumulation. Overall, this experiment provides information about selecting trellis systems and applied water amounts to optimize vineyard productivity and berry quality in warm/hot viticultural regions.
Speakers
RY

Runze Yu

Assistant Professor, California State University, Fresno
Co-authors
NT

Nazareth Torres

Universidad Pública de Navarra
NA
SK

Sahap Kaan Kurtural

Kurtural Vineyard Consulting
NA
Tuesday September 24, 2024 2:45pm - 3:00pm HST
Nautilus 1

3:00pm HST

CITR 1 - Hedging, Thinning, Controlled Release Fertilizer, and Oxytetracycline Trunk Injections to Mitigate Fruit Disorder Incidence in HLB-Affected 'Sugar Belle' Mandarin
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Global citrus production has been severely impacted by huanglongbing (HLB), a disease presumably caused by the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas). While there are not any commercial citrus cultivars currently available that have total resistance to this pathogen, several varieties show some degree of tolerance, including the LB8-9 ‘Sugar Belle’ mandarin. This cultivar was released by the UF/IFAS CREC Plant Improvement Team in 2009 and is known to be one of the most HLB tolerant varieties in HLB-endemic conditions when considering tree health. Fruit from this cultivar can be used for juicing or in the fresh market and with proper cultural care the trees consistently produce relatively high yields with typically an acceptable ratio of total soluble solids (TSS) to titratable acidity and value in pounds-solids per acre. Despite the improved tolerance to HLB in ‘Sugar Belle,’ many growers in Central and South Florida have had increased incidences of fruit disorders with this variety in the past several seasons. Fruit that are misshapen, have a poor peel color, or go soft on the tree are more common making this cultivar often undesirable for packing houses. The objective of this study is to determine if hedging the trees at different times (early summer, middle summer, or late summer), manually removing ~50% of the developing fruit in July (thinning), controlled release fertilizer applications, or oxytetracycline trunk injections will help mitigate some of the incidences of fruit disorders and increase overall fruit and juice quality at harvest. There were two sites used for this experiment (The Citrus Research and Education Center in Lake Alfred, FL, and Tamiami Citrus “Bee Branch Grove” in Avon Park, FL) and it was conducted over two seasons 2022-2024. Significant differences (p-value < 0.05) were discovered among the treatment groups in terms of TSS, titratable acidity, sugar:-acid ratio, pounds-solids per box, fruit size, yield, percent asymptomatic fruit, and peel rupture force. Despite evidence that some treatments may provide benefits to the grower, more research is needed to mitigate the soft fruit problem in ‘Sugar Belle’ mandarin.
Speakers
JV

Joe Volpe

University of Florida
Tuesday September 24, 2024 3:00pm - 3:15pm HST
South Pacific 4

3:00pm HST

HEMP 1 - Heavy Metal Application Timing Impacts Plant Growth in Cannabis sativa
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Cannabis sativa is a known hyperaccumulator of heavy metals (HM), and testing of hemp medicinal products is required for HM contaminants including arsenic (As), cadmium (Cd), and lead (Pb). The objective was to evaluate how the timing of HM applications impacts hemp growth. A plant experiment was conducted where 40 Cannabis sativa ‘Wife’ hemp plants were grown in deep water culture systems in a growth chamber. Aqueous nutrient solutions including combined As, Cd, and Pb were applied directly into the hydroponic solution on a weekly basis, with HM concentrations of 0.0, 0.5, and 1.0 mg HM/L. During the first six weeks, plants were grown under long days to promote vegetative growth, and 15 plants were harvested at the end of this vegetative growth phase. The remaining 25 plants were grown under short days to initiate flowering, with harvest 6 weeks later. Total dry mass (P < 0.05), shoot dry mass (P < 0.05), and root dry mass (P < 0.01) were significantly affected by HM application timing. The total and shoot dry mass was the highest for the control group, followed by the plants that received HM at 0.5 or 1.0 mg/L during the reproductive phase, and the least growth occurred in plants that received HM at 0.5 or 1.0 mg/L during the vegetative phase. Root dry mass decreased as HM concentration increased (P < 0.05). Flower dry mass was not significantly affected by HM application timing or concentration. Results highlight how exposure to HM at 0.5 to 1.0 mg/L markedly reduce biomass accumulation, especially when exposure occurs early in the production cycle.
Speakers
HM

Harrison Meekins

University of Florida
Co-authors
PF

Paul Fisher

University of Florida
NA
Tuesday September 24, 2024 3:00pm - 3:15pm HST
South Pacific 1

3:00pm HST

PB 1 - Precision Breeding Using CRISPR to Improve Production Traits in Blackberry
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Pairwise is a technology-focused food and agriculture company that makes tiny alterations to plant genetics to solve big problems. Powered by our best-in-class technology, Pairwise is harnessing new genomics technologies to create innovative new products. With our FulcrumTM platform, we accelerate innovation in plants and plant-based production systems, delivering value to people and our planet. Partnering with Plant Sciences, Inc. to access their elite germplasm, we created a platform to transform and edit tetraploid blackberry (Rubus sub. Rubus). We used the power of genetics and genomic tools to identify the candidate gene for thornless in blackberries and used CRISPR based gene editing to validate the trait. The identification of this gene will enable faster deployment of a thornless trait, an essential production trait, into blackberries. The gene may be broadly applicable to other Rubus species and horticultural crops such as roses.
Speakers
PM

Pradeep Marri

Pairwise Plants
Co-authors
Tuesday September 24, 2024 3:00pm - 3:15pm HST
South Pacific 3

3:00pm HST

PH 1 - Effects of Alternative Atmosphere Storage on the Postharvest Quality of Georgia-grown Blackberries
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Blackberries have several susceptibilities that contribute to the fruit’s high perishability resulting in a short shelf-life. The industry-standard technique for maintaining the postharvest quality is to store berries in a room with low temperature and high relative humidity to slow senescence. Despite the use of cold storage, the shelf-life of fresh-market blackberries can be short, limiting their marketing potential. The application of innovative technologies such as controlled atmospheres (CA), or the addition of gaseous ozone (O3) to the cold storage rooms could aid in maintaining the postharvest quality. During the 2023 blackberry season, three harvests were conducted paired with a sensory survey one day after. Four blackberry cultivars (Caddo, Ouachita, Ponca, Osage) were hand-picked, field-packed, and hand-sorted before being placed into cold storage. The storage conditions included a control of cold storage (1 °C, 95% RH), cold storage with additional controlled atmosphere (10% CO2 10% O2), and cold storage with gaseous ozone (0.5 ppm). The blackberries were kept under the above storage conditions for up to 21 days, with quality assessments occurring every seventh day. Quality assessments included sensory attributes of visual quality, weight loss, color, firmness, respiration rates, red drupelet reversion (RDR) presence, anthocyanin content, titratable acidity, and total soluble solids. Significant differences between treatments were recorded in fruit firmness of Caddo and Ouachita berries after seven days of storage. The CA and ozone treatments resulted in higher firmness of Caddo berries compared to the control. The CA and ozone treatments resulting in lower firmness of Ouachita berries compared to the control. RDR was separated by presence of RDR with the parameters none, low, and high. In each harvest, Ouachita had the highest presence of RDR after harvest compared to the other cultivars. Caddo exhibited low to no RDR in each harvest initially and after storage. Caddo was favored by panelists in the sensory survey related to the overall flavor and overall appearance. The experiment will be repeated during the 2024 blackberry season to evaluate the above cultivars’ aroma volatile compound levels using a GC/MS system.
Speakers
RC

Ramsey Corn

University of Georgia
Co-authors
AD

Angelos Deltsidis

University of Georgia
OG

Orestis Giannopoulos

University of Georgia
ZR

Zilfina Rubio

University of Georgia
Tuesday September 24, 2024 3:00pm - 3:15pm HST
South Pacific 2

3:00pm HST

VCM 1 - Evaluating the Effect of Three Algae Extracts Application on Three Crops Growth and Yield in Hawaii
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Food- and nutritional-security are among the highest concerns for Hawaii residents. The state imports about 85% of the consumed food and there’s roughly two-week worth of food locally at any given time. Local food production is costly due to high inputs cost. Algae extracts are known to supports plants' flowering and fruiting, increasing plant nutrient uptake, enhancing resistance and recovery from plant stress events, and increasing nutrient use efficiency and fertilizer assimilation. Three different algae extracts (Afrikelp, Acadian, and Kelpak) were evaluated for their effect on growth and yield of bush bean, bell pepper, and tomato in a randomized complete block design (RCBD) with 5 blocks. The algae extracts were applied 5 times during each growing season. The algae extracts were applied at dilution rate of 1:100 with a week between applications for the bush bean crop and two-week intervals for bell pepper and tomato crops. The results showed a highly significant (p < 0.01) increase in the three crops yield under all algae extracts compared to control (water only) treatment. The results also showed there was a significant (p < 0.05) difference between the algae extracts with highest yield recorded under Afrikelp extract compared to Acadian and Kelpak. The yield increase reached between 150-300% compared to control treatment.
Speakers Co-authors
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Kahili

3:00pm HST

VSF 1 - Heat Stress Effects on South Mississippi Grown Bunch Grapes
Tuesday September 24, 2024 3:00pm - 3:15pm HST
In the challenging climate of Mississippi, where high heat, rainfall, and humidity pose significant challenges to bunch grape (Vitis spp.) production, identifying resilient cultivars is essential for determining stress adaptation and sustainable agricultural practices. This study assessed the heat tolerance of nine interspecific hybrid bunch grape cultivars/selections (‘Ambulo Blanc’, ‘Black Spanish’, ‘Blanc du Bois’, ‘Lomanto’, ‘MidSouth’, ‘Miss Blanc’, ‘Muench’, OK392, ‘Victoria Red’) grown at the Mississippi Agricultural and Forestry Experiment Station South Mississippi Branch in Poplarville, Mississippi, in 2023. Stomatal density, stomatal conductance, transpiration, vapor pressure deficit, and chlorophyll fluorescence were evaluated both in the field and through leaf disks subjected to a 4-hour heat simulation. ‘Miss Blanc’ and OK392 exhibited the highest stomatal density, while ‘Black Spanish’ had the lowest. Monthly in-field measurements showed no significant differences in physiological measurements. Regarding specific cultivars undergoing the heat simulation, ‘Lomanto’ displayed elevated stomatal conductance and transpiration, contrasting with OK392 with lower values. ‘MidSouth’ showcased high chlorophyll fluorescence, whereas ‘Ambulo Blanc’ consistently displayed lower levels. ‘Miss Blanc’ and OK392 exhibited high vapor pressure deficit, while ‘MidSouth’ showed low values. Further analysis unveiled several correlations: a strong positive correlation between stomatal conductance and transpiration (r=0.9, P
Speakers
HW

Haley Williams

Mississippi State University
Co-authors
ES

Eric Stafne

Mississippi State University
NA
JR

Jenny Ryals

Mississippi State University
Tuesday September 24, 2024 3:00pm - 3:15pm HST
Nautilus 1

3:15pm HST

CITR 1 - Grove First: A Framework to Find Citrus Greening Treatments that are Safe, Affordable, and Available.
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Citrus greening (Huanglongbing, HLB) is considered one of the most devastating diseases affecting the global citrus industry. There is an urgent need to provide relief from HLB and restore profitable citrus production. Since 2005, over a billion dollars has been spent on research to find a solution to HLB. Trunk injection with the antibiotic oxytetracycline is the current treatment that Florida growers are using to manage the disease. To broaden the number of molecules available to growers to treat HLB a framework was developed to efficiently screen molecules in citrus groves, selecting those that enhance tree health over a season. The framework is based on the principles of the design-of-experiments (DOE). Utilizing the injection system developed by TJ Biotech (LLC), 88 molecules were injected into 8-year-old ‘Valencia’ sweet orange (Citrus × sinensis) trees grafted on ‘US-812’ (Citrus reticulata × Poncirus trifoliata) rootstock over a six-week period. The injections were divided into nine sets, with varying numbers of molecules injected in each set (12, 10, or 6). The injections were administered into the scion, approximately 5 cm above the graft union. Visual assessments of tree health index and canopy density were collected to evaluate changes in restoring tree horticultural traits. Ratings were recorded before injections and at 90 and180 days post-injections. In addition to health index and canopy density, a series of seven pictures were taken per tree on the injection day and subsequently at 30, 60, 90, and 180 days after injections. Pre-harvest fruit drops were measured by counting and removing any fruits on the ground beneath each tree. The total number of fruits on each tree was tallied at harvest to calculate the percentage of fruit drops for each tree. Yield, fruit, and juice quality were assessed at harvest. In this screening trial, trees injected with oxytetracycline have been used as a positive control to indicate enhancement in tree health. Results from the tree health index obtained at 90 and 180 days after injection showed that 17 molecules performed similarly or better than the oxytetracycline-treated positive control. We are partnering with regulatory consultants to identify those that are safe and affordable. New molecules for injection will require regulatory labeling.
Speakers
GL

Guilherme Locatelli

University of Florida
Co-authors
EC

Ellen Cochrane

University of Florida/USDA
NA
LR

Lorenzo Rossi

University of Florida
ML

Michelle L Heck

Emerging Pests and Pathogens Research Unit, USDA Agricultural Research Service/ Plant Pathology and Plant Microbe Interactions Section, School of Integrative Plant Science, Cornell University
NA
RN

Randall Niedz

U.S. Horticultural Research Laboratory, U.S. Department of Agriculture, Agricultural Research Service
NA
Tuesday September 24, 2024 3:15pm - 3:30pm HST
South Pacific 4

3:15pm HST

HEMP 1 - Photoperiod Sensitive CBD Hemp Response to Fertigation Nitrogen Inputs in a Raised-bed Plasticulture Growing System
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Nitrogen (N) fertilization plays a key role in determining the productivity and quality of horticultural crops and limited information is available on the N requirements of photoperiod-sensitive CBD hemp (Cannabis sativa L.). With the objective of providing recommendations on N fertilization to CBD hemp growers a field study was conducted in Pennsylvania to evaluate the response to N inputs of two photoperiod sensitive CBD hemp genetic resources: a clone named ‘FunDip’ (The Hemp Mine) propagated using rooted cuttings and ‘Sour Kush’ (Kayagene) propagated using feminized seeds. Both selections were planted mid-June on raised beds mulched with black polyethylene film and served by drip irrigation. Plants were established at 1.5-m in-row and 2.4-m between rows. After planting both CBD hemp selections were fertigated weekly with urea (46-0-0) using seasonal application rates equivalent of 84, 168, 252, and 336 kg/ha of N. An unfertilized control was used to account for the N available through the soil and to estimate the crop N use efficiency. Treatments were arranged according to a split plot experimental design with four replications. Nitrogen treatments were randomized within the main plots while hemp selections were randomized within subplots. Each experimental unit had a minimum of 12 plants, unfertilized border rows and in-row areas were used as buffer zones to avoid fertilizer cross-contamination between different N applications rates. Plant response to N inputs was evaluated conducting biometric assessments during the growing season and at final harvest. Representative plants were sampled to measure leaf and inflorescence, stem, and total plant fresh and dry biomass. Oven-dried plant tissue samples were analyzed for their total N content to estimate the plant N accumulation during the growing season. At every biometric assessment, soil samples were collected and analyzed for pH, EC, and nitrate (NO3-) content. A quadratic response to N inputs was observed in both selections. At final harvest, the total fresh plant biomass of both genotypes was maximized with the application of 252 kg/ha of N and declined at higher N rate. However, no increase in plant dry biomass were observed in plants fertigated with over 168 kg/ha of N in both genotypes. An accumulation of NO3-N and associated increase in EC was observed with the progression of the growing seasons especially in plots fertigated with over 84-168 kg/ha of N, in Sour Kush and FunDip, respectively, which suggest an excess of N was applied with N rates exceeding 84-168 kg/ha.
Speakers
FD

Francesco Di Gioia

Pennsylvania State University
Co-authors
AC

Alyssa Collins

Pennsylvania State University
NA
BM

Ben Morrison

Pennsylvania State University
NA
MK

Misha Kwasniewski

Pennsylvania State University
NA
TJ

Trevor Johnson

Pennsylvania State University
NA
Tuesday September 24, 2024 3:15pm - 3:30pm HST
South Pacific 1

3:15pm HST

PB 1 - Double CRISPR Knockout of Pectin Degrading Enzymes Improves Tomato Shelf-life While Ensuring Fruit Quality
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Tomato fruit is an important and popular commodity worldwide. One of the main challenges for the fresh market tomato industry is postharvest deterioration, which is mainly determined by the rate of softening. This rate can affect tomato shelf-life, pathogen susceptibility, and fruit waste. The softening rate is regulated by multiple factors, but mainly by the pectin composition of the cell wall, which is remodeled, disassembled, and solubilized by enzymes during fruit ripening; a process that induces and determines the fruit softening in fleshy fruits. The main pectin-degrading enzymes that act on the pectin backbone are Polygalacturonases (PG) and pectate lyases (PL). In this study, we generated a double CRISPR knockout PGPL. We investigated the combined functions of SlPG2a and SlPL on fruit quality traits in postharvest, including shelf-life attributes like firmness and water loss, fruit marketability, and disease incidence. We also assessed additional attributes impacting consumer acceptance, such as taste and aroma. Our findings revealed that the tomato ripening enzymes SlPG2a and SlPL act additively, significantly affecting fruit firmness and shelf-life. Additionally, aspects of fruit quality, such as external color, sugar: acid ratio, and aroma volatiles, were improved or not affected in the double CRISPR knockout PGPL when compared to control. The discoveries of this research provide new insights into the influence of pectin backbone degradation on fruit physiology and postharvest quality, which can be used in crop improvement programs to make fruit more resilient in the supply chain without compromising consumer-based quality traits.
Speakers
avatar for Isabel Ortega Salazar

Isabel Ortega Salazar

University of California, Davis
Tuesday September 24, 2024 3:15pm - 3:30pm HST
South Pacific 3

3:15pm HST

PH 1 - Examining the Effect of Storage Temperatures on Chilling Injury Incidence of Georgia-Grown Peaches
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Peaches are climacteric fruit that can continue ripening after harvest. When stored at elevated temperatures, peaches exhibit higher respiration rates and increased ethylene production, which makes low-temperature storage key for quality preservation. Cold storage slows down metabolic activities responsible for senescence. However, temperatures between 36 and 46°F (2.2-7.7°C) might induce a disorder commonly known as chilling injury, hence, this range has been named by many scientists as the “killing zone”. The disorder is detrimental to peach quality as it affects the flesh texture, appearance, and fruit juiciness overall. Depending on the severity, peaches might not show external symptoms of the disorder which usually appears after transfer to ambient conditions. Factors such as varietal differences, storage durations, and growing conditions may influence the severity of chilling injury symptoms. Very little research has been done in the Southeast regarding chilling injury incidence, while many of the newer cultivars have never been investigated. This project aimed to investigate the appearance of chilling injury symptoms in important peach cultivars grown in the Southeastern United States. Peaches were stored at five different temperatures of 33, 36, 41, 46, and 50°F (0.5, 2.2, 5, 7.7, and 10°C) and 95% relative humidity for up to four weeks. Quality evaluations occurred on days 0, 7, 14, 21, and 28 after harvest, which were followed by three days of ambient storage to allow for the development of chilling injury. Quality measurements included weight loss, decay incidence, total soluble solids, titratable acidity, firmness, as well as visual appearance. Results show that 33°F storage temperatures had lower respiration. Higher storage temperatures of 41, 46, and 50°F resulted in increased weight loss and lower firmness readings. Peaches stored at 33 and 36°F were juicier until the 21st day of storage. All tested temperatures were tolerated for a storage period of 7 days, with no visible symptoms. On the other hand, storage durations longer than 14 days at temperatures of 36, 41, and 46°F showed the highest chilling injury incidence. More research is currently underway in order to create a map of chilling injury tolerance across different cultivars that are important for the Southeastern region.
Speakers
avatar for Orestis Giannopoulos

Orestis Giannopoulos

University of Georgia
Co-authors
AD

Angelos Deltsidis

University of Georgia
DC

Dario Chavez

University of Georgia
NA
RC

Ramsey Corn

University of Georgia
Tuesday September 24, 2024 3:15pm - 3:30pm HST
South Pacific 2

3:15pm HST

VCM 1 - Early Season Soil Tarping Impacts on Weed Pressure and Onion Production in Eastern South Dakota
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Onions are a globally popular kitchen staple, not only for their flavor, but also their nutritional value. According to the Agricultural Marketing Research Center, onions are the fourth most consumed fresh vegetable in the United States. To bring this valued crop to our kitchen tables, quality onions must be produced in high quantities to meet consumer demands. Since they are especially susceptible to weed competition due to their minimal canopy cover, weed management is an important consideration for onion production. One weed management tool is soil tarping. This study evaluated the impact of two types of tarping (solarization and occultation) and duration of tarping (6-, 4- and 2-weeks) on weed control in Patterson and Candy onion production. Field experiments were conducted during the 2023 growing season in Brookings, South Dakota. Solarization was conducted using clear tarps secured with sandbags and buried edges. Tarps were placed in April and May at respective weeks before removal on May 30. Immediately following tarp removal, each plot was tilled, and rows of onion transplants were planted. Occultation was evaluated using white side up and black side up silage tarps, both applied at respective weeks before removal and onion planting. Each treatment plot filled a twenty-four by ten-foot area. A randomized complete block design with four blocks and ten treatment plots per block including a control with no tarp was established. Response variables for data collection included weed type, height, and biomass as well as onion yield. All tarping treatment plots resulted in less weed pressure than the control at tarp removal. Broadleaf weed count collected during the growing season was different among tarp treatments (p=0.03). Data collected June 12 showed 6-week clear tarp to have 67% less broadleaf weed count per acre than the control, and 74% less than the 4-week black tarp. There was no difference in onion yield due to tarping treatment. This may have been due to biweekly weeding events that evened out treatment effect on weeds over the growing season. There was, however, a difference in yield between Candy and Patterson onion cultivars (p=0.02). Candy averaged a marketable count of 19 of 48 planted onions while Patterson averaged a marketable count of 36 of 48 onions planted. Soil tarping may be an effective option for farmers to reduce early season weeds in onion production, however, it should be used alongside other management strategies to obtain a viable yield.
Speakers
HV

Hannah Voye

South Dakota State University
Co-authors
KL

Kristine Lang

South Dakota State University
RB

Rhoda Burrows

South Dakota State University
NA
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Kahili

3:15pm HST

VSF 1 - Rethinking Chill Models: The Role of Cold Hardiness, Freezing Temperatures and Daily Fluctuation on Promoting Dormancy Progression and Release
Tuesday September 24, 2024 3:15pm - 3:30pm HST
This study addresses fundamental questions in bud dormancy, specifically the impact of temperature on chill accumulation and cold hardiness on dormancy release. We evaluated bud cold hardiness (CH) and time to budbreak responses of grapevines throughout chill accumulation under three treatments: constant (5°C), fluctuating (-3.5 to 6.5 °C daily), and field conditions (Madison, WI, USA), during three dormant seasons. Findings reveal that lower temperatures in chill treatments result in greater cold hardiness gains (CHfield>CHfluctuating>CHconstant). All treatments reduce time to budbreak with increased chill accumulation. However, when time to budbreak was adjusted to remove cold acclimation effects, treatment effectiveness changed. Notably, existing chill models (North Carolina, Utah, and Dynamic) fail to accurately describe adjusted budbreak responses. Our results demonstrate how chill treatment effectiveness changes when adjustments for uneven acclimation are considered. We propose a new model that includes freezing temperatures and enhances chill accumulation under fluctuating conditions.
Speakers
AA

Amaya Atucha

University of Wisconsin Madison
Co-authors
AK

Al Kovaleski

University of Wisconsin-Madison
NA
BA

Beth Ann Workmaster

University of Wisconsin Madison
NA
MG

Michael G North

University of Wisconsin Madison
NA
Tuesday September 24, 2024 3:15pm - 3:30pm HST
Nautilus 1

3:30pm HST

CITR 1 - Can We Improve Growth and Production in HLB- Affected Citrus Trees Using Plant Growth Regulators?
Tuesday September 24, 2024 3:30pm - 3:45pm HST
Huanglongbing (HLB) disease is arguably the biggest concern for citrus growers in Florida causing a drastic more than 75% decline in citrus-bearing acreage since 2005. HLB symptoms include sparse canopy, poor leaf growth and development, ultimately resulting in yield losses. Standalone applications of plant growth regulators (PGRs) and certain antibiotics have been reported to reduce the impact of HLB on tree growth and promote new flush growth. However, very little research has been done on synergistic effect of PGRs and antibiotics on tree growth and yield. The goal of HLB mitigation strategies is to promote a denser canopy, enhancing source to sink ratio as trees with dense canopies are known to produce high fruit yield. Thus, we initiated a field study to evaluate foliar applications of PGRs (auxins, cytokinins, and gibberellins) and trunk injections of Oxytetracycline (OTC) in 9-year-old orchards of Valencia on ‘Swingle’ rootstock in central Florida. This is the first research in citrus where PGRs are being applied according to tree phenology. The experimental design is a split-plot with a completely randomized block design with 8 replications. The antibiotic programs (with and without OTC injections) are assigned to the main plots, while the PGR treatments assigned to the subplots consist of an no PGR control, PGR applications with varying concentrations, and PGR applications with constant concentrations throughout the year. Parameters such as leaf area, fresh weight, dry weight, water content, chlorophyll content, starch content and carbohydrate content from leaf samples are recorded every three months starting from July 2023. Over 9 months no consistent pattern of PGR or OTC treatment was observed for vegetative traits. Nonetheless, Non-OTC trees showed higher leaf water content compared to OTC during the dry season months of October and January. Regarding yield, the study suggests that both PGR treatments, when applied with or without OTC lead to significant improvement in yield. PGR variable treatment showed 30% improvement in yield efficiency compared to both the control and PGR Constant treatments. No difference is observed between OTC and Non-OTC programs in terms of yield efficiency. These findings suggest that use of PGR treatments regardless of use of antibiotics can be beneficial for growers.
Speakers
PV

Prudhvi Vulchi

University of Florida, CREC
Co-authors
AL

Amit Levy

University of Florida
NA
TV

Tripti Vashisth

University of Florida
Tuesday September 24, 2024 3:30pm - 3:45pm HST
South Pacific 4

3:30pm HST

HEMP 1 - Field Evaluation of Controlled Release Fertilizer in Support of Best Management Practices for Industrial Hemp in Florida
Tuesday September 24, 2024 3:30pm - 3:45pm HST
Successful field cultivation of hemp (Cannabis sativa L.) in Florida is restricted to summer months when rainfall is highest, as hemp is exceptionally sensitive to daylength. Given the prevalence of soils in Florida with poor nutrient and water holding capacities, controlled release fertilizer (CRF) could be ideally suited for outdoor cultivation due to its slow-release profile. To assess the effectiveness of CRF to support plant growth while minimizing water quality risks, the plant growth and biomass production of four hemp cultivars (‘Wife’, ‘Sunset Improved’, ‘FunDip’, and ‘Belle’) were evaluated in response to nitrogen and phosphorous availability from ten CRF formulations in Apopka, Florida during the summer of 2023. Plant growth was assessed post-transplant and monthly thereafter until harvest by measuring the height, widest width, and width perpendicular to the widest width of each hemp plant. At harvest, plants were severed at the soil surface and dried at 70 degrees Celsius for three days. For each plant, the total plant biomass and total flower biomass was measured. Significant differences in plant growth and biomass production were found among varieties; however, minimal differences were found in plant growth and biomass production within variety in response to varying CRF formulations. These results suggest that CRF can provide adequate levels of fertility for the growth and development of hemp cultivated outdoors in Florida, and that selection of hemp cultivar affects plant growth and yield.
Speakers
avatar for Shea Keene

Shea Keene

University of Florida
Co-authors
AW

Ajit Williams

University of Florida
NA
BP

Brian Pearson

Oregon State University
NA
HS

Hardeep Singh

University of Florida
NA
JB

Jehangir Bhadha

University of Florida
NA
LS

Lakesh Sharma

University of Florida
Dr. Lakesh Sharma is an assistant professor of soil fertility and sustainable agriculture at the University of Florida in Gainesville, FL. Lakesh has been farming since he was a child on his own farm. His academic school journey started in 2000. He is currently working on nutrient... Read More →
TS

Tamara Serrano

University of Florida IFAS-TREC
NA
WD

Winniefred D Sharma

University of Florida
NA
ZB

Zachary Brym

University of Florida
NA
Tuesday September 24, 2024 3:30pm - 3:45pm HST
South Pacific 1

3:30pm HST

PB 1 - Functional Characterization of a Candidate Bacterial Wilt Resistance Gene in Tomato
Tuesday September 24, 2024 3:30pm - 3:45pm HST
Bacterial wilt, caused by Ralstonia solanacearum (Rs), is an economically devastating plant pathogen that causes rapid death and has been widely distributed worldwide. Rs is a soil-borne bacterium that plugs plant xylem vessels, causing wilt and ultimately death in tomatoes (Solanum lycopersicum L.) and many other economically important crops. The most cost-effective and efficient means of managing Rs is planting resistant cultivars. However, acceptable Rs resistance in these genotypes is tightly linked to small fruit size, preventing development of BW-resistant large fruited tomato cultivars. Previous research has shown that a highly resistant cultivar's candidate resistance gene (Sl-BWR) is linked to qualitative resistance of Rs. Our preliminary data indicates that overexpression of the resistant allele in a susceptible cultivar background confers resistance comparable to the wild-type resistant allele. There is ongoing work to generate susceptible allele overexpression lines and knockout lines from the susceptible and resistant cultivars. We hypothesize the resistant allele knockouts will be susceptible to Rs, indicating that the candidate gene is the primary resistance factor. The gene could be functionally characterized to elucidate the Rs resistance mechanism in tomatoes to be deployed in a breeding program to develop resistant cultivars against bacterial wilt.
Speakers
JD

James Duduit

North Carolina State University
Co-authors
TA

Tika Adhikari

North Carolina State University
NA
WL

Wusheng Liu

North Carolina State University
Tuesday September 24, 2024 3:30pm - 3:45pm HST
South Pacific 3

3:30pm HST

PH 1 - Postharvest melatonin application maintains quality of jackfruit bulbs by alleviating enzymatic browning and oxidative stress under low temperature storage
Tuesday September 24, 2024 3:30pm - 3:45pm HST
Jackfruit bulbs are susceptible to postharvest browning which is a major factor limiting shelf life and marketability. In this investigation, the impact of postharvest melatonin (MLT) application on enzymatic browning and antioxidant metabolism in jackfruit bulbs was evaluated. Jackfruit bulbs were dipped in different concentrations of MLT (0, 0.05, 0.1 and 0.2 mmol L-1) prior to cold storage at 4 ± 1 °C temperature and 85-90% relative humidity over the duration of 20d. MLT application considerably delayed the process of senescence as demonstrated by a reduction in browning index and softening of bulbs with 0.1 and 0.2 mmol L-1 MLT application, respectively. At the end of the storage period, 0.2 mmol L-1 MLT treatment significantly maintained higher ascorbic acid (46.9 %), total phenolics (22.3%) and total carotenoids (26.3%) compared to control. Whilst 0.1 mmol L-1 MLT application curtailed fruit weight loss (46.0%) and improved total flavonoid content (16.7 %) and DPPH radical scavenging activity (12.5%) as compared to the control. The levels of polyphenol oxidase and guaiacol peroxidase were significantly lower in 0.1 mmol L-1 and 0.2 mmol L-1 MLT treated bulbs, respectively. The activity of antioxidant enzymes including catalase, superoxide dismutase, and ascorbate peroxidase was improved with the application of 0.2 mmol L-1 MLT. In addition, all MLT treatments effectively reduced malondialdehyde, lipoxygenase and hydrogen peroxide radicals. These findings suggest that dip treatment of MLT (0.1 and 0.2 mmol L-1) effectively lessen flesh browning along with maintenance of antioxidant potential and postharvest quality of jackfruit bulbs.
Speakers
JK

Jashanpreet Kaur

PhD Scholar, Edith Cowan University
Co-authors
AW

Andrew Woodward

Edith Cowan University, Joondalup, Western Australia, Australia
NA
EA

Eben Afrifa-Yamoah

Edith Cowan University, Joondalup, Western Australia, Australia
NA
HM

Hafiz Muhammad Shoaib Shah

Edith Cowan University, Joondalup, Western Australia, Australia
NA
MS

Muhammad Sohail Mazhar

Department of Industry, Tourism and Trade Northern Territory
NA
ZS

Zora Singh

Edith Cowan University
Tuesday September 24, 2024 3:30pm - 3:45pm HST
South Pacific 2

3:30pm HST

VCM 1 - Evaluating the effect of fertilization and controlled-water deficit on growth and yield of compact vegetable plants
Tuesday September 24, 2024 3:30pm - 3:45pm HST
Sales of compact vegetable bedding plants for the home-gardening market segment are increasing. However, production guidelines for these new crops are limited. Our objective was to assess the effect of fertilizer use and controlled-water deficit (CWD) on plant growth during production, and after-production effects on fruit yield. ‘Siam’ tomato and ‘Basket of Fire’ pepper plants were grown in a greenhouse for 4 and 6 weeks, respectively, using 10-cm containers. Half of the plants received a water-soluble fertilizer once a week, and the other half were irrigated with tap water only, relying on the starter fertilizer charge in the substrate (EC = 0.9 mS·cm−1). Plants were irrigated when the substrate volumetric water content (VWC) reached 0.15, 0.30, 0.45, or 0.60 m3·m–3. After the experiment, plants were transplanted into 20-cm containers, top-dressed with controlled-release fertilizer (CRF), and grown for another 10 weeks to evaluate carryover treatment effects. Plants that did not receive fertilizer were shorter and had a lower shoot dry mass (SDM) than those that were fertilized, regardless of species. Shoot height of tomato followed a quadratic trend in response to CWD, which peaked at 0.45 m3·m–3, whereas SDM linearly increased with increasing VWC. No growth responses to CWD were measured for pepper. However, plants of both species that did not receive fertilizer looked chlorotic and had a lower chlorophyll concentration than those that were fertilized (15 and 32 µmol·m–2 for tomato and 15 and 27 µmol·m–2 for pepper, respectively). Plant greenness increased after applying CRF, suggesting that applying fertilizer right before shipping could increase quality of these plants when grown with limited or no fertilizer to control growth. After the carryover phase, differences in plant growth were maintained, and differences in yield was measured between fertilized and non-fertilized plants (56 and 48 fruits for tomato and 153 and 112 fruits for pepper, respectively). Our results show that growth and yield of compact tomato and pepper plants are affected to a larger extent by fertilizer use than by substrate VWC.
Speakers
MF

Michael Fidler

Purdue University
Co-authors
CG

Celina Gomez

Purdue University
Tuesday September 24, 2024 3:30pm - 3:45pm HST
Kahili

3:45pm HST

CITR 1 - Methyl Salicylate and Gibberellic Acid For The Rehabilitation Of HLB- Affected Sweet Oranges.
Tuesday September 24, 2024 3:45pm - 4:00pm HST
Huanglongbing (HLB), is a serious bacterial disease affecting citrus trees. HLB, poses a significant threat to Florida
Speakers
GK

Gurleen Kaur

CREC, University of Florida
Co-authors
SP

Shalini Pareek

University of Florida-Citrus Research and Education Center
NA
TL

Taylor Livingston

University of Florida- Citrus Research and Education Center
NA
TV

Tripti Vashisth

University of Florida
Tuesday September 24, 2024 3:45pm - 4:00pm HST
South Pacific 4

3:45pm HST

PB 1 - Novel Short Synthetic Promoters for Constitutive Expression in Dicot Species
Tuesday September 24, 2024 3:45pm - 4:00pm HST
Determining the promoter motifs involved in regulating transcription, the first process of gene expression, is critical for synthetic promoter engineering. A gene’s promoter contains cis-regulatory elements, or motifs, which are binding sites for transcription factors (TFs) to initiate and drive transcription. Many bioinformatic tools have been developed for determining statistically overrepresented regions, representing sites of potential cis-regulatory elements, that are shared across groups of promoters. Combining the results produced by multiple bioinformatic tools can lead to improved detection accuracy of motifs conferring biological activity. In the present study, we compiled a set of 11 known soybean constitutive gene promoters under the assumption that some of the promoters are regulated by the same transcription factor(s). Seven bioinformatic tools capable of de novo motif discovery were used to determine potentially shared motifs within the promoters, which were then mapped back to the original promoter sequences. A total of 64 overlapping motif regions (OMRs) were commonly detected amongst the 11 constitutive promoters, and each OMR was cloned individually in front of the minimal CaMV 35S promoter driving GUSPlus reporter gene expression. Transient tobacco leaf agroinfiltration and subsequent quantitative GUS activity assays were used to determine each OMR’s ability to drive reporter gene expression. We found that 20 of the 64 bioinformatically-determined OMRs drove functional gene expression significantly higher than the basal levels conferred by the minimal 35S promoter. Of the 20 functional OMRs, 11 drove GUSPlus expression at levels from just twice that of the minimal 35S promoter up to nearly half of the full-length 35S promoter. We also transformed these 20 functional OMRs individually into Arabidopsis. While GUS staining is still ongoing, we identified a few OMRs which showed strong promoter strength in single-copied homozygous Arabidopsis seedlings. These functional OMRs are strong candidates for further characterization and can be used for crop improvement.
Speakers Co-authors
EB

Emily Brooks

North Carolina State University
NA
NM

Nathan Maren

North Carolina State University
NA
WL

Wusheng Liu

North Carolina State University
Tuesday September 24, 2024 3:45pm - 4:00pm HST
South Pacific 3

3:45pm HST

PH 1 - Catalysis of 1-Methylcyclopropene Degradation By Non-Target Materials: Metals and Metal Salts
Tuesday September 24, 2024 3:45pm - 4:00pm HST
1-Methylcyclopropene is a cyclic olefin that inhibits ethylene action and is released as a gas from a formulated cyclodextrin. Different concentrations of 1-MCP are used globally in the fruit industry to enhance the preservation of quality attributes. The concentrations applied cannot be considered stable due to losses to target and non-target sites within the storage or treatment room environment. Copper is used in cooling systems because it transfers heat more efficiently than many other materials, but it is also used as a catalyst for chemical modification. So, we investigated the absorption or degradation of 1-MCP by various metals, including copper. These forms included metal bars (hot and cold-rolled steel, aluminum, galvanized metal, silver, gold, stainless steel, and brass), copper pipes (polished, oxidized, and with patina) and copper salts [covellite (CuS, copper II sulfide); eriochalcite (CuCl22H2O, copper II chloride); chalcopyrite (CuFeS2, copper iron sulfide); cupric carbonate (CuCO3, copper II carbonate); chalcocite (Cu2S, copper I sulfide), cuprite (Cu2O, copper I oxide); chalcanthite (CuSO45H2O, copper sulfate); tenorite (CuO, copper II oxide), and cupric acetate (Cu(CH3CO2)2, copper II acetate)], which possessed copper atoms at different levels of oxidation. The metal pieces had a surface area of 435 cm2, and the powders weighed 1 g. We put the materials in 480-mL glass jars and added 50 μL L−1 of 1-MCP gas to the headspace. Gas concentrations were measured at 0, 2, 4, 6, and 24 h in both humid and dry conditions at room temperature. The loss of 1-MCP was more pronounced in humid condition than in dry condition except when exposed to cupric carbonate. While covellite, eriochalcite, and chalcopyrite caused a 1-MCP loss of over 90% within 24 h in both conditions, stainless steel, aluminum, galvanized iron mesh, silver and galvanized iron yielded a 1-MCP loss below 10%. On the other hand, the impact of copper pipes on reducing 1-MCP is evident, and the reduction of 1-MCP also increases as the oxidation level of the copper increases. Based on mass spectral analysis of the headspace in the treatment chambers, the decrease of 1-MCP appears to occur by adsorption by the materials, polymerization, and disintegration into break-down products. The implications for 1-MCP reductions in commercial treatment rooms will be discussed.
Speakers
OH

Ozge Horzum

Ankara University
NA
Co-authors
NS

Nobuko Sugimoto

Michigan State University
NA
PE

Philip Engelgau

Michigan State University
NA
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Tuesday September 24, 2024 3:45pm - 4:00pm HST
South Pacific 2

3:59pm HST

Water Utilization and Management 2 (WUM 2)
Tuesday September 24, 2024 3:59pm - 6:00pm HST
Irrigation Management With Spreadsheets in Small Farms - Gustavo Haddad Souza Vieira
Assessing Micro-Irrigation Clogging Risk Through Water Quality Classification Systems - Juan Cabrera Garcia
Development of an Open-source, Autonomous Irrigation Controller for Horticultural Applications - Andrew Bierer
Microbial Community Composition and Accumulation Of Biofilms In Irrigation Pipes Using Nutrient Solutions with Different Organic Loads - Juan Cabrera Garcia
ATP vs Petrifilm: Techniques to Quantify Microbial Communities for Water Quality Analysis - Dharti Thakulla
Water use and crop coefficients for outdoor nursery ornamentals in 15-gal containers - Gerry Spinelli
Quantification of irrigation and stormwater runoff volume, sediment load, and nutrient load when producing nursery crops - James Owen
Water Supply Resilience Through Florida-Friendly Landscaping - Michael Dukes

Moderator
avatar for Gerry Spinelli

Gerry Spinelli

University of California Cooperative Extension
Irrigation management in nurseries and greenhouses
Tuesday September 24, 2024 3:59pm - 6:00pm HST
Nautilus 1

4:00pm HST

WUM 2 - Irrigation Management With Spreadsheets in Small Farms
Tuesday September 24, 2024 4:00pm - 4:15pm HST
In the Central Serrana region, Espírito Santo state, Brazil, there is a predominance of small farms and the technological level used is still low, especially in terms of water use. Irrigation management can provide greater water use efficiency and promote optimization of crop productivity and conservation of water resources. Thus, this study aimed to implement an irrigation management program, using simplified electronic spreadsheets, for drip irrigation, based on the climatological water balance, for family-based farmers. We selected four spots located in the towns of Barra de Bom Destino; Barra de Jatibocas; Baixo Sossego and headquarters of the Itarana County, state of Espírito Santo, Brazil, with drip irrigation systems, irrigating banana, arabica coffee, guava and conilon coffee crops. Irrigation management was carried out for seven months, using daily temperature and precipitation data, obtained from maximum and minimum thermometers and rain gauges, respectively. The values were collected by farmers, noted in tables and registered in electronic spreadsheets, which provided recommendations for irrigation times. In adjacent areas, irrigation was carried out according to its local traditional rule, in the way that farmers did before the implementation of management, with the purpose of comparing the volume of water used in the two forms of irrigation. The banana irrigator followed the irrigation management guidelines using the spreadsheet and, comparing the two areas, achieved a 7.5% increase in productivity and a 9.34% increase in water use efficiency. Farmers in areas with arabica coffee and guava managed irrigation, but were not organized to collect crop productivity data. For guava cultivation, an increase in fruit load was visible in the area with irrigation management. The Conilon coffee farmer did not follow the irrigation management recommendations, considering the task laborious and complicated. Irrigation management continues to be carried out on farms with banana, guava and arabica coffee. New neighboring producers expressed interest in using electronic spreadsheets. Work has been done on the development of new tools for irrigation management, using smartphones, to facilitate the task of calculating irrigation management. Therefore, it is expected that with the continuity of the work, the practice of irrigation management will be more widespread among farmers and they will decide to use it.
Speakers
avatar for Gustavo Haddad Souza Vieira

Gustavo Haddad Souza Vieira

Full Professor, IFES campus Santa Teresa
Agronomist,Ph. D. in Agricultural Engineering. Full Professor. Irrigation, Agrometeorology, Horticulture, Coffee Crop.
Co-authors
Tuesday September 24, 2024 4:00pm - 4:15pm HST
Nautilus 1

4:00pm HST

AI Innovation for Horticulture - Part 1
Tuesday September 24, 2024 4:00pm - 6:00pm HST
Sponsoring Professional Interest Groups
Technology: Coordinator Milt McGiffen - milt.mcgiffen@ucr.edu
Teaching Methods: Coordinator, Kathryn Orvis – orvis@purdue.edu
Controlled Environment: Coordinator, Kent Kobayashi - kentko@hawaii.edu

Supporting Professional Interest Groups
Federal Partners: Matthew Mattia - Matthew.Mattia@usda.gov
Plant Biotech: Kedong Da - kda@ncsu.edu
Ornamentals/Landscape and Turf; Youping Sun - youping.sun@usu.edu
Local Food Systems: Charles H. Parrish II - chip.parrish@pm.me

Artificial intelligence and related topics, e.g., robotics, have been a long time coming in
agriculture. For decades there have been predictions of intelligent robots replacing
humans, and large farms run by a few humans with many autonomous tractors and
other devices. But with the now widespread use of artificial intelligence in everyday life,
the moment has arrived. We developed this colloquium by casting a wide net out to all
the Professional Interest Group Chairs, and have assembled talks and demonstrations
from general topics to specific applications.

Two online meetings were held, where Professional Interest Groups officers and those interested suggested
speakers and discussed topics. Further discussions over email helped fill in the details
to create this colloquium.

We will have a block of speakers for the diverse topics we present below, as well
as panel discussions on how AI is and can be incorporated into various aspects of
Horticulture, so that there is ample time for questions and discussion.

Title: Overview of the Colloquium

Speaker: Milt McGiffen, Cooperative Extension Specialist, Department of Botany and Plant Sciences,
University of California, Riverside, CA.

AI in Ornamentals

Title: FloraScore: An App for Rapid Assessment of Pollinator Attractiveness to Annuals
and Perennial Plants.


Description: Customers are interested in buying annuals and perennials that support
pollinators. Protocols for rapid assessment in flower trail evaluations are not
available. We have developed a mobile app that can be used to analyze in real time the
users’ observational data and quantitatively rank the relative utility of observed cultivars
to pollinator communities. This app takes into account pollinator groups, relevant floral
characteristics and landscape.

Presenter: Harland Patch
Assistant Research Professor
Department of Entomology
Penn State University
549 Ag Sciences & Industries Building
University Park, PA 16802

Title: Approach to Biodiversity Protection: Employing AI and IoT Systems for the
Containment of Box Tree Moth Proliferation.


Description: The box tree moth (BTM, Cydalima perspectalis) is an invasive pest first
confirmed in Niagara County, New York in 2021. This invasive pest can significantly
damage and potentially kill boxwood (Buxus species) plants if left unchecked. This
presentation describes our advances in combining deep learning algorithms for
enhanced computer vision with IoT-enabled smart traps, to facilitate the early detection
and continuous monitoring of BTM populations and to protect the prevalent ornamental
boxwood in U.S. landscapes.

Presenter: Yanqiu Yang (she/her)
Ph.D. Graduate Research Assistant
Department of Agricultural and Biological Engineering
Pennsylvania State University
3 Agricultural Engineering Building
University Park, PA 16802

Title: Landscapes from Words: The Future of Landscape Design with AI.

Description: The ongoing text-to-graphic artificial intelligence (AI) revolution has the
potential to change the field of Landscape Architecture dramatically. The ability to
produce original high-quality graphics, manipulate the viewer's perspective of images,
and amend the rendering style through text inputs are significant advancements that will
inform new design process models. These changes can lead to expanded design
exploration, improved accessibility for non-designers to contribute to creating visual
concepts, enhanced ability to integrate data analysis and visualizations, and
streamlined collaboration between clients and project stakeholders using a shared
visual language. This talk focuses on two dimensions of change that may result from the
rapid evolution of text-to-graphic AI, including (1) faster iterations and exploration of
design options and (2) the advancement of methods that result in more inclusive and
responsive design. In the classroom, students are just beginning to acknowledge the
existence of text-to-graphic AI, which allows them to experiment with text-based design
options that allow them to quickly visualize and explore a wide range of site program
alternatives. Nevertheless, how do we manage the ethical and creative boundaries
within an academic setting? In a research context, methods supporting rapid
manipulation of both generated images and existing landscape photography represent
advances that allow for greater collaboration surrounding landscape design decisions
(Incorporating resilience strategies, protecting vernacular landscape elements that
support a sense of place, or representing new design proposals that modify the
landscape). These approaches allow stakeholders to gain remarkable advances in

influencing the design process through shared visualization development. However, as
with any emerging technology, practitioners, educators, and researchers need to
respond to the challenges presented by text-to-graphic AI by developing and testing
new design process models and public engagement techniques that can improve
landscape decision-making and streamline collaboration.

Presenter: Aaron Thompson
Assistant Professor
Department of Horticulture and Landscape Architecture
Purdue University
625 Ag Mall Drive
West Lafayette, IN 47906

Title: Developing Guidelines for Extension’s Use of ChatGPT and Other Generative AI
Tools.


AI in Extension
Dr. Masiuk is a member of ASHS and has agreed to speak.
Description: A new technological era marked by the advent of Artificial Intelligence
(AI), particularly generative AI and Large Language Models (LLMs) like ChatGPT has
necessitated the need to navigate this domain with a compass of ethicality, safety, and
effectiveness. Penn State’s experience developing guidelines for Extension’s use of
generative AI tools which will be shared and discussed.

Presenter: Michael Masiuk
Assistant Director – Horticulture Programs
Penn State Extension
342 Agricultural Administration Building
University Park, PA 16802

Panel: 30 minute panel with the above speakers, to allow time for Q&A and discussion.


Moderator Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
avatar for Harland Patch

Harland Patch

Penn State University
Dr. Harland Patch focuses his current research on understanding the behavioral and molecular mechanisms associated with pollinator host plant choice, and the structure of plant-pollinator communities. Dr. Patch is also involved in ongoing projects to determine the interacting causes... Read More →
KO

Kathryn Orvis

Professor, Purdue Univ
avatar for Yanqiu Yang

Yanqiu Yang

PhD candidate, The Pennsylvania State University
Yanqiu YangFounder & AI Lead Engineer at bioWatch | PhD Candidate at PSU | President-Elect of the Ag & Bio Engineering Graduate Student Council (GSC)Hi there! I’m Yanqiu, and I’m on a mission to bring cutting-edge technology to the fields and orchards. As the Founder & AI Lead... Read More →
Tuesday September 24, 2024 4:00pm - 6:00pm HST
Coral 3

4:00pm HST

Scholars Ignite
Tuesday September 24, 2024 4:00pm - 6:00pm HST
Competition Entry https://ashs.org/page/SIEntry

The Graduate Student Activities Committee hosts this competition to allow graduate students members (both MS and PhD) a fun and exciting way to communicate the impact of their research projects and scholarly activities.
Graduate students make compelling presentations in three minutes using no more than one single PowerPoint slide or visual aid. The purpose of the presentation is to generate awareness, stimulate thought, and inspire attendees to appreciate the breadth and depth of horticultural research and scholarly activities. Graduate students will meet other students and scientists, learn about an array of research topics and other creative and scholarly activities across ASHS, and most importantly have fun!

The competition is designed similar to other popular three to five minute thesis and research presentation events (e.g. Three minute thesis, ‘Ignite’ or Scholars’ Studio) occurring around the globe, and done especially well in Australia, British Columbia, and the University of Washington.

Winners will receive a cash award of $500, $250, and $100 for the top three places, respectively.
The winners are announced at the Student Awards Night.
Students must enter by the deadline of Sept 1st. 
Applicants may use only one Introductory Slide (using the ASHS provided template) and one Presentation Slide for a total of 2 slides. The Introductory Slide must follow the format of the template and include Title of Presentation (Calibri 44 bold), Student’s Name (Calibri 32 bold), Advisor(s) Name (Calibri 28) and Institution’s Name (Calibri 28). The Presentation Slide must be one single page without any animation. Students may use any color, background or font for their Presentation Slide but not for the Introductory Slide. Slides need to be in the 16:9 format. Both slides must be presented in 3 minutes. Once the student reaches the podium the timer will start and after 3 minutes we will move to the next student.
Download the 2024 Scholars Ignite PowerPoint Template here.
Submit PowerPoint and Transition Slide to: https://ashs.org/page/SIEntry

Tuesday September 24, 2024 4:00pm - 6:00pm HST
Coral 2

4:00pm HST

Interest Group Session: Plant Intellectual Property
Tuesday September 24, 2024 4:00pm - 6:00pm HST
ASHS Intellectual Property Interest Group Session
Proposal Proposed by: Fruit Breeding Interest Group and Intellectual Property Interest Group

Plant intellectual property is an important topic for plant breeders, universities and private companies who handle the release and exchange of plant materials. On the one hand, properly protecting new cultivars is critical to protect the genetic integrity of the genotype and credit the developer. On the other hand, understanding the types of intellectual property laws relevant to plants is important for breeders/researchers to exchange materials for collaborative evaluation and development. Therefore, this interest group session will focus on plant intellectual protection and material transfer. We will invite speakers from public and private plant breeding programs as well as experts on intellectual property laws to share their knowledge and advice on following areas: Domestic plant protection, International plant protection, Domestic plant material transfer, and International plant material transfer. The topic of intellectual property was voted by members of both interest groups (Fruit Breeding Interest Group and Intellectual Property Interest Group) as a high priority area. This session will greatly benefit plant breeders, researchers, and intellectual property officers.

Coordinator(s)
  • Sushan Ru, Auburn University, Auburn, United States
Moderator(s)
  • Julia Harshman, Duda Farm Fresh Foods, United States
Speaker/Participant(s)
  • Matthew Clark, University of Minnesota, Department of Horticulture, United States
    Plant Protection and Material Transfer in the University of Minnesota Grape and Apple Breeding Program

Moderator Speakers
SR

Sushan Ru

Auburn University
Tuesday September 24, 2024 4:00pm - 6:00pm HST
South Pacific 1

4:00pm HST

Interest Group Session: Restoration and Utilization Efforts of Germplasms and Wild Crop Relatives at the USDA
Tuesday September 24, 2024 4:00pm - 6:00pm HST
Leveraging the inherent genetic diversity conserved in plant resource collections is key to new crops, new cultivars, and adapted germplasm with improved traits that provide food security for a growing population, remain productive amidst rapid climate change, meet shifting consumer demands, and enhance sustainability and efficiency. The USDA National Plant Germplasm System manages large and genetically diverse plant collections representing crop plant species and many of crop wild relatives (CWR) that have significant impacts on crop production. In this Special Topic Session hosted by the Federal Partners Interest Group, scientists of the Agricultural Research Service (ARS) will discuss the current efforts and future perspectives on the restoration and utilization of germplasms and CWR at the USDA with a special focus on fruit, nut, and beverage crops.

Coordinator(s)
  • Lisa Tang, USDA-ARS Appalachian Fruit Research Station, Kearneysville, WV, United States
Moderator(s)
  • Lisa Tang, USDA-ARS Appalachian Fruit Research Station, Kearneysville, WV, United States
  • Matthew Mattia, USDA-ARS U. S. Horticultural Research Laboratory, Fort Pierce, FL, United States
Speaker/Participant(s)
  • Lisa Tang, USDA-ARS Appalachian Fruit Research Station, Kearneysville, WV, United States
    Introduction of the Federal Partners special session (5 mins)
  • Gayle Volk, USDA, Fort Collins, Colorado, United States
    The USDA-ARS National Plant Germplasm System Strategic Plan: A roadmap to conserve and utilize U. S. plant genetic resources (15 mins)
    Summary: The USDA-ARS National Plant Germplasm System (NPGS) conserves more than 620, 000 accessions of plant genetic resources of crops and crop wild relatives which annually distribute 200, 000+ samples globally. As directed by the 2018 Farm Bill, an NPGS Strategic Plan was developed to address the backlogs in maintenance, characterization, and to enhance utilization. This presentation will provide information about the impacts of the NPGS and details about the NPGS Strategic Plan, which, when funded, will result in: 1) More plant germplasm maintained disease-free, securely backed up, and readily available; 2) Expanded knowledge of the intrinsic genetic variation and high-value traits in NPGS collections; and 3) New plant germplasm with valuable traits acquired, safeguarded and developed. This presentation is authored by Gayle M. Volk (USDA), Marilyn L. Warburton (USDA), Moira Sheehan (Cornell University), Christina Walters (USDA), Stacey Estrada (USDA), Glenn Hanes (USDA), Jim McFerson (USDA), and Peter K. Bretting (USDA-retired).
  • Chris Gottschalk, USDA-ARS Appalachian Fruit Research Station, Kearneysville, WV, United States
    Into the wild: utilization of wild crop relatives the USDA ARS apple pre-breeding program (15 mins)
    Summary:
  • Nahla Bassil, USDA-ARS National Clonal Germplasm Repository, Corvallis, OR, United States
    Crop wild relatives of temperate fruits at the Corvallis Genebank: Uses and prospects (10 mins)
    Summary:
  • Michael Hardigan, USDA-ARS, Corvallis, OR, United States
    Crop wild relatives of temperate fruits at the Corvallis Genebank: Uses and prospects (10 mins)
    Summary:
  • Tracie Matsumoto, USDA-ARS Daniel K. Inouye Pacific Basin Agricultural Research Center, Tropical Plant Genetic Resources and Disease Research Unit, Hilo, HI, United States
    Sub-Tropical/tropical Fruit, Nut, and Beverage Clonal Repository in Hilo, Hawaii (15 mins)
    Summary: The National Clonal Germplasm Repository for Tropical Fruit, Nut and Beverage Crops is located in Hilo, Hawaii and is a part of the National Germplasm Repository System and USDA ARS DKI PBARC Tropical Plant and Genetic Resources Unit. The repository is responsible for collecting, maintaining, evaluating, and distributing germplasm of tropical/subtropical fruit and nut crops. Crops include Pineapple (Ananas), Breadfruit (Artocarpus), Starfruit (Averrhoa), Peach palm (Bactris), Pili nut (Canarium), Papaya (Carica and Vasconcellea), Coffee (Coffea) Longan (Dimocarpus), Litchi (Litchi), Macadamia (Macadamia), Acerola (Malpighia), Rambutan and Pulasan (Nephelium), and Guava (Psidium). In addition to the field and greenhouse collections, we are actively investigating new methods to propagate and effectively manage the collections. We work to characterize the collection for resistance to pest and diseases and genetically characterize the germplasm to determine potential gaps for future collections.
  • Qingyi Yu, USDA-ARS Daniel K. Inouye Pacific Basin Agricultural Research Center, Tropical Plant Genetic Resources and Disease Research Unit, Hilo, HI, United States
    Exploring germplasm diversity to understand the domestication process of papaya (15 mins)
    Summary: Papaya (Carica papaya L.), originating and domesticated in southern Mexico and Central America, is widely cultivated in tropical and subtropical regions due to its nutritional benefits and the commercially significant proteolytic enzyme, papain. While wild papaya yields small, seedy fruits with minimal edible flesh, domesticated papaya varieties can weigh over five pounds. Wild papaya populations are exclusively dioecious, whereas cultivated papaya is predominantly gynodioecious, although certain dioecious cultivars exist. In this study, we conducted whole-genome resequencing of 86 diverse papaya accessions, comprising 63 cultivars and 23 wild accessions. To identify regions undergoing selection during domestication and improvement, we scanned for areas exhibiting a drastic reduction in nucleotide diversity in cultivars compared to wild accessions. Our results suggest that papaya domestication involved selecting fruit quality traits such as taste and flesh color. Moreover, we re-sequenced the male-specific region of the Y (MSY) in 24 wild males and the hermaphrodite-specific region of the Yh chromosome (HSY) in 12 cultivated hermaphrodites. The Yh sequence is highly similar to one Y haplotype (MSY3), exclusive to wild dioecious populations in the north Pacific region of Costa Rica. The low MSY3-Yh divergence suggests that hermaphrodite papaya resulted from human domestication.

Moderator
LT

Lisa Tang

USDA-ARS Appalachian Fruit Research Station
Speakers
CG

Christopher Gottschalk

USDA ARS
During his Ph.D. studies, Dr. Gottschalk studied the molecular mechanisms that control flowering in apple as they relate to seasonal bloom times and biennial/alternate bearing in diverse apple germplasm, from wild species to cultivated varieties. Moreover, he investigated plant growth... Read More →
Tuesday September 24, 2024 4:00pm - 6:00pm HST
Kahili

4:14pm HST

Root Growth and Rhizosphere Dynamics (RHIZ)
Tuesday September 24, 2024 4:14pm - 5:30pm HST
Investigating the Effect of Pecan Rootstock on Rhizosphere Soil and Root Microbial Communities - Xinwang Wang
Enhancing Urban Food Production: A Multi-Omics Investigation of Microbe-Mediated Soil Improvement and Plant Nutrition in New York City Farms - Yejin Son
The Effect of Reclaimed Water on Young Blueberry Seedling Root Architecture Using Rhizotron Technique - Yasmeen Saleem
Root Characterization Analysis of Navajo Peach Seedlings - Reagan Wytsalucy
Characterizing Root Dynamics and Phenology of Hops in a Subtropical Climate Using an In-situ Root Imaging System - Alvaro J. Bautista
Effects of Reclaimed Water on Blueberry Seedling Growth and Root Morphology - Yasmeen Saleem
Moderator
YS

Yejin Son

Cornell University
Tuesday September 24, 2024 4:14pm - 5:30pm HST
South Pacific 4

4:14pm HST

Ecological Physiology 1 (EcoPhys 1)
Tuesday September 24, 2024 4:14pm - 6:00pm HST
Evaluating Plasticity and Acclimation of Linked Hydraulic Traits of Different Taxa Across a Climatic Gradient in the Western U.S. - Amelia Keyser Gibson
Climate Ready Stomata: Stomata Morphology and Physiology Varies Across Western US Sites and Irrigation Deficit Treatments in Rosa and Hibiscus syriacus Cultivars - Miro Stuke
Ice Formation and Progression in Rhododendron, and a Mechanistic Hypothesis for Winter Thermonasty of Leaves - Rajeev Arora
Trade-Offs in Reproductive Traits and Buds' Freezing Survival Strategies Among Prunus Species - Camilo Villouta
Potential Genes Involved in the Adaptation of Potato to Long Term Heat Stress - Jiwan Palta
Species-specific Differences in Leaf Photosynthetic Rate when Substituting Far-red Light for PAR Photons - John Ertle
Investigating Dormancy and Germination Characteristics to Promote Restoration Success in the Northern Great Plains - Bret Lang
Moderator
JE

John Ertle

PP Systems
NA
Tuesday September 24, 2024 4:14pm - 6:00pm HST
Coral 1

4:14pm HST

Vegetable Breeding 1 (VGBR 1)
Tuesday September 24, 2024 4:14pm - 6:00pm HST
Genome-wide Association Study and Genome Prediction of Verticillium Wilt Resistance in Spinach - Kenani Chiwina
Spinach Seed for Grain Consumption: Feasibility and Potential for Genetic Improvement - Carlos Avila
Progress and Insights Into Downy Mildew Resistance Mapping Efforts in Spinach - Gehendra Bhattarai
Screening Baby Leaf Salad Greens for Downy Mildew Resistance - Shunping Ding
Detection of Novel Lettuce Fusarium Wilt Pathogenic Variants in California - Santosh Nayak
Unraveling Gene Regulation on the Interaction of Lettuce (Lactuca sativa L.) and Xanthomonas hortorum pv. vitians Causal Agent of Bacterial Leaf Spot. - Byron Manzanero
Exploring Physiological Traits as Predictors of Heat Content in Chile Peppers (Capsicum annuum L.) - Muhammad Ibrar Khan

Moderator
Tuesday September 24, 2024 4:14pm - 6:00pm HST
South Pacific 3

4:15pm HST

EcoPhys 1 - Evaluating Plasticity and Acclimation of Linked Hydraulic Traits of Different Taxa Across a Climatic Gradient in the Western U.S.
Tuesday September 24, 2024 4:15pm - 4:30pm HST
Increasing drought conditions and variable water availability under climate change impact plant productivity, ecosystem function and the global carbon cycle, with many species-level responses remaining unknown. Variation in response and ability to acclimate to decreased water availability differs among plant species and across biomes. This project utilized a preexisting water deficit trial of horticultural taxa across sites in the Western U.S. to assess the interactions between acclimation to climate and water availability across a growing season. Four focal taxa, Physocarpus ‘Diabolo’, P. ‘Little Devil’, Cercis canadensis and C. occidentalis shared across three locations in Washington, Oregon and Utah were measured for physiological and hydraulic traits on the leaf and stem scale in response to irrigation treatment. The cultivars of Physocarpus are popular landscape shrubs known for their distinctive purple foliage yet understudied physiologically. C. occidentalis and C. canadensis have distinct native ranges, with the former originating west of the Rocky Mountains while the latter is east coast in origin, thus their performance was compared across these western U.S. sites. Full gas exchange, specific leaf area, 13C isotope discrimination, hydraulic conductivity, stomatal conductance, ΦPSII, were analyzed and water use efficiency was calculated each taxon at each location. Impacts of site, treatment, taxa and change across the growing season were analyzed on this suite of traits. Results show distinctions in water use strategy by climatic location (p: 1e-05) and between closely related species and cultivars. Additionally, physiological measurements indicate measurable physiological plasticity across the growing season. These findings indicate the importance of setting on the ability of different plant cultivars to acclimate to water stress, taxa-level differences among horticulturally important species, and overall knowledge of plant drought response, knowledge gaps that are crucial to address in the face of anthropogenic climate change.
Speakers
AK

Amelia Keyser Gibson

University of Washington
Co-authors
DH

Darren Haver

South Coast Research and Extension Center
NA
JS

Jared Sisneroz

University of California, Davis
LN

Lloyd Nackley

Oregon State University
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
LO

Loren Oki

University of California, Davis
MS

Miro Stuke

University of Washington
SH

Soo Hyung Kim

University of Washington
US

Ursula Schuch

University of Arizona
YS

Youping Sun

Utah State University
Tuesday September 24, 2024 4:15pm - 4:30pm HST
Coral 1

4:15pm HST

RHIZ - Investigating the Effect of Pecan Rootstock on Rhizosphere Soil and Root Microbial Communities
Tuesday September 24, 2024 4:15pm - 4:30pm HST
Pecans (Carya illinoinensis), the most valuable native North American nut crop, are commonly propagated through grafting to maintain desired traits from parent trees. Successful pecan cultivation relies on scion varieties, rootstocks, and soil conditions. This study investigated the microbial abundance and diversity in soils and roots of a southern rootstock (87MX5-1.7) and a northern provenance ('Peruque') in a rootstock test orchard, both grafted with a 'Pawnee' scion cultivar in the USDA ARS Pecan Breeding program. The 16S ribosomal RNA of bacteria and ITS of fungi were sequenced and annotated into trophic and nutrient-related groups to characterize the rhizosphere microbiota. The results showed fungal dominance over bacteria, with Peruque roots having a higher relative abundance of saprotroph fungi compared to 87MX5-1.7, while 87MX5-1.7 exhibited higher levels of nitrogen fixation-related bacteria. Despite no significant difference in diversity index, the presence of symbiotrophs, especially the ectomycorrhizal fungi, exhibited distinct ectomycorrhizal fungi, which may lead to a divergent pathway of nutrient translocation between these two rootstocks. The study suggests rootstocks from different origins shape rhizosphere microbiota differently, affecting nutrient uptake and potentially nut yield. Exploring rootstock-fungi combinations could enhance grafting success and ultimately increase nut yield.
Speakers
avatar for Xinwang Wang

Xinwang Wang

Plant Geneticist, USDA ARS
Co-authors
BT

Braden Tondre

USDA ARS Southern Plains Agricultural Research Center
NA
LZ

Lu Zhang

Oklahoma State University
TX

Tingying Xu

Oklahoma State University
NA
WR

Wei Ren

Oklahoma State University
NA
Tuesday September 24, 2024 4:15pm - 4:30pm HST
South Pacific 4

4:15pm HST

VGBR 1 - Genome-wide Association Study and Genome Prediction of Verticillium Wilt Resistance in Spinach
Tuesday September 24, 2024 4:15pm - 4:30pm HST
Verticillium wilt, caused by Verticillium dahliae Kleb., poses a significant threat to spinach (Spinacia oleracea L.) production, necessitating genetic resistance as the primary defense against this disease. This study conducted a comprehensive genome-wide association study (GWAS) to identify single nucleotide polymorphism (SNP) markers linked to Verticillium wilt resistance in spinach and to evaluate genomic prediction for disease resistance. GWAS utilized a panel of 98 spinach germplasm accessions and 20,742 SNPs obtained from whole-genome resequencing. Various statistical models, including GLM, MLM, FarmCPU, and BLINK, were employed using the GAPIT 3 tool for analysis. Two quantitative trait loci (QTL) regions on chromosome 6 were found to be significantly associated with Verticillium wilt resistance. Specifically, SNP SOVchr6_29382746 at 29,382,746 bp and three SNPs (SOVchr6_86904401, SOVchr6_86906249, and SOVchr6_86906255) at 86,904,401 bp and 86,906,249 bp, respectively, demonstrated notable associations with disease resistance. Genomic prediction exhibited high accuracy, with a prediction ability (GA) represented by an r value of 0.95 for the panel. The identified SNP markers, along with the high prediction ability, offer valuable tools for breeders to select Verticillium wilt-resistant spinach plants and lines through molecular breeding, incorporating marker-assisted selection (MAS) and genomic selection (GS) strategies.
Speakers
KC

Kenani Chiwina

University of Arkansas
NA
Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
BM

Beiquan Mou

USDA-ARS
NA
HX

Haizheng Xiong

University of Arkansas
Tuesday September 24, 2024 4:15pm - 4:30pm HST
South Pacific 3

4:15pm HST

WUM 2 - Assessing Micro-Irrigation Clogging Risk Through Water Quality Classification Systems
Tuesday September 24, 2024 4:15pm - 4:30pm HST
Clogging poses significant economic risks in greenhouse micro-irrigation systems. While water quality classification systems aim to assess the overall risk of clogging in micro-irrigation systems, they haven’t been evaluated for their ability to predict potential clogging based on water quality characteristics, particularly in controlled environment agriculture. Understanding these causes can inform robust thresholds and effective water management strategies to mitigate economic risks associated with clogging. This project aimed to evaluate if the existing classification systems could be used to identify the cause of clogging in micro-irrigation systems in greenhouses. Water from eight commercial greenhouses with reported clogging was analyzed for physical, chemical, and biological properties to rate the risk of clogging according to the classification systems. In general, iron and manganese from the fertilizers and high microbial load resulted in high ratings. However, the ratings lacked insight into the specific causes of clogging, disregarding interactions among chemical and microbial factors and qualitative characteristics of specific microbial phenotypes (e.g., production of polysaccharides or iron oxidation) that lead to clogging. Furthermore, the systems overemphasize nutrient levels typically used in greenhouse fertigation as the cause of clogging—which is not commonly observed in practice. Enhancing these systems requires parameters that reflect interactions among water quality parameters and the influence of microbial traits on clogging. Further research needs to develop these parameters in new systems with robust and precise thresholds in which emitter performance, profitability, and sustainability are affected.
Speakers
JC

Juan Cabrera Garcia

University of Missouri
Co-authors
MT

Mayra Toro Herrera

University of Connecticut
RR

Rosa Raudales

University of Connecticut
Tuesday September 24, 2024 4:15pm - 4:30pm HST
Nautilus 1

4:15pm HST

Marketing and Economics Group Meeting
Tuesday September 24, 2024 4:15pm - 5:00pm HST
Moderator
Tuesday September 24, 2024 4:15pm - 5:00pm HST
Sea Pearl 3

4:29pm HST

Organic Horticulture 1 (ORGH 1)
Tuesday September 24, 2024 4:29pm - 5:45pm HST
Assessing Producers’ Interest and Barriers in the Transition to Organic Principles - Brenton Breland
Merging Traditional Ecological Knowledge with Modern Organic Practices: A Case Study in Participatory Research - Erin Silva
Growing Urban Organic Farms in Iowa: New Initiatives and Support - Kathleen Delate
Bridging the Gap: Culinary Breeding Network Facilitates Collaboration in Variety Development - Lane Selman
Metabolomic Analysis Provides Novel Insight Into the Evaluation of Organic Tomato Fruits - Jashanpreet Kaur
Moderator
ES

Erin Silva

UW-Madison
Tuesday September 24, 2024 4:29pm - 5:45pm HST
Lehua Suite

4:30pm HST

EcoPhys 1 - Climate Ready Stomata: Stomata Morphology and Physiology Varies Across Western US Sites and Irrigation Deficit Treatment
Tuesday September 24, 2024 4:30pm - 4:45pm HST
Stomatal morphology dictates the maximum stomatal conductance and relates to plant water use efficiency and carbon assimilation rate. Aspects of stomatal morphology, including size characteristics and density, are plastic in some taxa, can respond to environmental stressors, and are thought to be relevant in drought acclimation within an individual. The Climate Ready Landscape Plants (CRLP) trial consists of 6 sites across the Western U.S. that have installed common garden drought experiments that utilized daily ETo to implement three water deficit treatments. Stomatal conductance and stomatal images were collected from 3 cultivars of Hibiscus syriacus and 3 cultivars of Rosa spp. from 4 of these sites: Seattle, WA; Aurora, OR; Davis, CA; and Irvine, CA. Stomatal images were measured to determine stomatal density and size, which was used to calculate gsmax. Differences between stomatal traits were tested between sites and water deficit treatments using ANOVA. Correlation between gsw and gsmax were determined with regression analysis. PCA was used to determine which site characteristics and treatments primarily explain observed differences. Here we aim to test 1) Are stomatal morphological traits plastic across water deficit treatments and sites in multiple Rosa and Hibiscus syriacus varieties? 2) Does measured stomatal conductance (gsw) correlate with morphologically derived anatomical maximums (gsmax)? 3) Do site characteristics across the maritime Western US predict physiological and morphological stomatal traits? Findings reveal important ecological and horticultural considerations in plant stress response to drought and acclimation potential across an environmental and latitudinal gradient. The results can help in plant selection and categorization of species vulnerability, based on ability to manipulate stomatal characteristics in response to water deficit.
Speakers
MS

Miro Stuke

University of Washington
Co-authors
JS

Jared Sisneroz

University of California Davis
LN

Lloyd Nackley

Oregon State University
NA
LO

Lorence Oki

University of California Davis
NL

Natalie Levy

University of California South Coast Research and Extension Center
NA
RC

Ryan Contreras

Oregon State University
SH

Soo Hyung Kim

University of Washington
YS

Youping Sun

Utah State University
Tuesday September 24, 2024 4:30pm - 4:45pm HST
Coral 1

4:30pm HST

ORGH 1 - Assessing Producers’ Interest and Barriers in the Transition to Organic Principles
Tuesday September 24, 2024 4:30pm - 4:45pm HST
In the changing landscape of horticulture, sustainability and organic practices have taken center stage. As of the 2021 USDA Organic Certified Survey, 17,445 certified organic farms representing 4,895,279 acres operated in the United States. Our research aims to understand the motivations and barriers that producers encounter when transitioning from conventional to organic production. Mississippi State University partnered with the University of Nebraska – Lincoln as part of the USDA AMS Transition to Organic Partnership Program (TOPP) whose focus is on supporting mentorships, helping overcome barriers, and educating producers. Following a TOPP-sponsored workshop in November 2023, it was noted that both beginning and experienced farmers were very interested in the process of transitioning to organic production. Participants noted their decision to transition was “very much influenced” by economics, market demand, environmental concern, health, and ethics. A review of literature revealed that, while there is a significant body of research on sustainable practices, there remains a gap in understanding the challenges that producers face. To bridge this gap and address the key findings from our workshop, a 43-question national survey was developed. It addressed motivations and barriers while also gathering demographic data to contextualize responses. Producers were questioned about cover crops, crop rotation, no-till farming, and composting among other practices. Social, environmental, and technical concerns were also addressed. Responses included motivations driven by environmental consciousness as it relates to soil health, reduced synthetic chemical inputs, and the goal of improving and maintaining biodiversity on their farms reiterating our previous findings. Producers indicated that they are encouraged by the amount of information available concerning organic production practices; however, they noted a knowledge-implementation gap. Financial constraints and space limitations were also concerns. The survey functions as the inception point for a case study following a beginning farmer in Calhoun City, Mississippi as they adopt organic principles in a region where the use of these growing practices is less than common. The insights gathered from the workshop, national survey, and case study will guide the understanding of producers’ motivations and will serve to inform policymakers, extension services, and the horticulture community at large. This ongoing project and its explorations are not only timely but also critical in shaping a future where horticulture aligns with the ethos of conservation and social equity.
Speakers
BB

Brenton Breland

Mississippi State University
Co-authors
CC

Christine Coker

Mississippi State University
RS

Ronald Stephenson

University of Nebraska-Lincoln
NA
Tuesday September 24, 2024 4:30pm - 4:45pm HST
Lehua Suite

4:30pm HST

RHIZ - Enhancing Urban Food Production: A Multi-Omics Investigation of Microbe-Mediated Soil Improvement and Plant Nutrition in
Tuesday September 24, 2024 4:30pm - 4:45pm HST
Urban agriculture (UA) is an emerging food production system in which farmers grow crops within cities. However, many urban farmers face challenges with their compost soils, including poor soil structure and low nutrient availability. This study aimed to utilize beneficial microbes, such as arbuscular mycorrhizal fungi (AMF) and phosphorus solubilizing bacteria (PSB), to address soil aggregation and biological phosphorus (P) cycling in UA soils while also assisting urban farmers in generating higher economic returns. We cultivated Bush Champion II Hybrid Tomatoes (an indeterminate tomato cultivar) in three organic urban farms in New York City in 2022 under four different treatments: 1) Control tomatoes, which were not treated with PSB or AMF; 2) Tomatoes treated with PSB; 3) Tomatoes treated with AMF; and 4) tomatoes treated with PSB and AMF. Our hypothesis posited that the positive interactions of PSB and AMF would synergistically enhance soil phosphorus cycling and carbon accumulation and, thereby, promote plant growth and nutrition. Our findings indicate that the combined application of AMF and PSB increased the overall abundance of soil microbiomes, as measured by flow cytometry. There was also an increase in the production of soil-aggregating proteins and soil acid phosphatase activity. Additionally, the nutrient uptake by tomatoes, including calcium (Ca), potassium (K), and phosphorus (P), was enhanced. We also employed omics approaches using deep sequencing metagenomics and metaproteomics to generate meaningful insights into how AMF and PSB interacted with soil native microbial populations and defined soil microbiome functions. Our findings offer novel insights into the characteristics and functions of soil microbiomes in UA soils. This knowledge will contribute to advancing the potential of beneficial microbes in enhancing food production within urban agriculture systems.
Speakers
YS

Yejin Son

Cornell University
Tuesday September 24, 2024 4:30pm - 4:45pm HST
South Pacific 4

4:30pm HST

VGBR 1 - Spinach Seed for Grain Consumption: Feasibility and Potential for Genetic Improvement
Tuesday September 24, 2024 4:30pm - 4:45pm HST
Spinach production is constantly challenged by endemic diseases that significantly reduce producers’ income. Even when resistant cultivars and cultural practices are used, mild disease damage can happen, negatively affecting quality and therefore reducing its commercial value. In contrast, under those conditions, spinach could still produce seed for grain with valuable nutritional content that can fetch premium prices for the gluten-free niche markets. This project evaluated grain production as an additional source of income by assessing yield potential, nutritional quality, and economic feasibility and potential for improvement. A total of ~200 USDA-NPGS accessions were evaluated for GWAS. For all nineteen amino acids evaluated, a wide range in content was observed. E.g. aspartic acid population mean was 106.5 nmol/g with a minimum of 36.2 nmol/g and a maximum of 353.9 nmol/g. Similar results were observed for all eight minerals evaluated. E.g. K population mean was 9,998.1 mg/kg with a minimum of 3,227 mg/kg and a maximum of 24,770 mg/Kg. High diversity can be used to improve nutritional content in spinach seed. Several SNP markers associated with amino acid and mineral content were identified in more than one nutrient, indicating pleiotropic genetic control. Furthermore, protein digestibility tests indicate that spinach provides ~50% of all amino acids required in the diet as compared with Amaranth and Quinoa protein in grain that provided ~20% of all amino acid required. Therefore, indicating spinach grain has a higher nutritional content as compared with highly demanded Amaranth and Quinoa grains. Finally, a partial budgeting approach was used to assess the economic feasibility of producing spinach seeds for grain. The added costs totaled US$ 218.71/ac, including custom harvesting (US$ 24/ac), an additional application of fertilizers (US$ 17.36/ac) and fungicide (US$ 62.54/ac), extra irrigation costs (US$ 60.63), and US$ 54.18/ac in associated interest on production expenses. The break-even price of seeds was estimated to be equal to US$ 0.20/lb when the average experimental yield was considered (i.e., 1,089lbs/ac). Producing seed for grain could expand the farmer portfolio, increase farmed acreage, and fringe products.
Speakers Co-authors
Tuesday September 24, 2024 4:30pm - 4:45pm HST
South Pacific 3

4:30pm HST

WUM 2 - Development of an Open-source, Autonomous Irrigation Controller for Horticultural Applications
Tuesday September 24, 2024 4:30pm - 4:45pm HST
An open-source data-driven irrigation controller, "Open_Irr", was developed by USDA-ARS as a low-cost (≤ $250 USD) entry point to autonomous irrigation installations in horticultural production and research applications. The device is reliant on granular-matrix type Watermark soil tension sensors (n≤16) from which it acts as a datalogger; sensors can be partitioned into 4 groups for water management in which readings can be used to output a logic-level signal for opening valving to initiate irrigation events. Here, we demonstrate the use of the device in research applications for imposing drought stress in containerized plantings of apple (Malus domestica). Our primary objectives were to (i) determine the utility of using granular matrix type soil tension sensors for predicting plant physiologic responses, measured by growth habit, infrared gas exchange, and chlorophyll fluorescence, for improvement of decision support systems; and (ii) determine potential differences in cultivar performance under water deficit conditions. A trial examined performance of ‘B.9’ rootstock grafted to ‘Autumn Gala’, ‘CrimsonCrisp’, and ‘Golden Delicious’ scions at set soil matric potential thresholds for irrigation events (-25, -40, -60, and -80 kPa). A second trial examined five rootstock cultivars (‘B.10’, ‘B.9’, ‘G.11’, ‘G.935’, and ‘G.969’) grafted to a common ‘Honeycrisp’ scion as plant available water contents of the soil were theoretically progressively decreased by 5% each week. Correlation matrices between aspects of physiology and soil matric potential revealed Pearson’s r ≤ |0.43| yet further regression analysis offered potentially useful data shapes warranting further exploration. A piecewise regression suggested soil matric potential could predict, to an extent (r2 = 0.29), the rate of change in leaf water potential upon exposure to water deficit. The break-point of the piecewise regression in leaf and edaphic potentials was respectively -30.6 kPa and -0.73MPa, which may prove useful for incorporation in developing irrigation decision support systems. The pattern of stomatal response to deficit suggested enhanced stomatal regulation capacity of ‘Gala’ relative to other scions in which nonstomatal factors likely contributed to short term maintenance of photosynthetic C assimilation rates. Similarly, the ‘G.935’ rootstock demonstrated superior sensitivity to water deficit through rapid stomatal closure relative to other cultivars. Refinement of the relationships between arduous measures of physiologic function with correlated easy-to-automate proxy measures is advised for potential advancement of irrigation decision support systems.
Speakers
AB

Andrew Bierer

USDA-ARS, AFRS
Co-authors
LT

Lisa Tang

USDA-ARS Appalachian Fruit Research Station
Tuesday September 24, 2024 4:30pm - 4:45pm HST
Nautilus 1

4:45pm HST

EcoPhys 1 - Ice Formation and Progression in Rhododendron, and a Mechanistic Hypothesis for Winter Thermonasty of Leaves
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Evergreen leaves of Rhododendron species inhabiting temperate/montane climates are typically exposed to both high radiation and freezing temperatures during winter when photosynthetic biochemistry is severely inhibited. This could lead to accumulation of excess energy (radiation) in photosynthetic reaction centers causing photoinhibition or photooxidative damage. Cold-induced ‘thermonasty’, i. e. lamina rolling and petiole curling/drooping, can reduce the amount of leaf area exposed to solar radiation and has been associated with photoprotection in overwintering rhododendrons. The present study was conducted on natural, mature plantings of a cold-hardy and large-leaved thermonastic North American species (R. maximum) during winter freezes. Infrared thermography was used to determine initial sites of ice formation, patterns of ice propagation, and dynamics of the freezing process in leaves to understand the temporal and mechanistic relationship between freezing and thermonasty. Results indicated extracellular freezing in leaves always preceded the initiation or intensification of thermonasty. Ice initially formed in the vascular tissue of the midrib and then propagated into other portions of the vascular system/venation. Ice was never observed to initiate or propagate into palisade, spongy mesophyll, or epidermal tissues. These observations, together with the leaf- and petiole-histology, and a simulation of the rolling effect of dehydrated leaves using a cellulose-based, paper-bilayer system, suggest that thermonasty occurs due to anisotropic contraction of cell wall cellulose fibers of adaxial versus abaxial surface as the cells lose water to ice present in vascular tissues.
Speakers
RA

Rajeev Arora

Iowa State University
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Coral 1

4:45pm HST

ORGH 1 - Merging Traditional Ecological Knowledge with Modern Organic Practices: A Case Study in Participatory Research
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Research in plant ecology and sustainable farming advocate for increasing crop diversity on farms over monocultures. Crop diversity provides many ecosystem services, but mainstream farming relies heavily on mechanical and chemical solutions known to degrade land quality to ensure optimal yields. For centuries, Indigenous peoples in North America maintained sustainable cropping systems characterized by crop diversity and minimal inputs, such as the Three Sisters system. To integrate this knowledge into current research, we collaborated with Indigenous corn growers in Wisconsin interested in growing their traditional corn varieties with cover crops seeded between the rows. Growers are interested in knowing which cover crop mixtures synergize well with their corns while suppressing aggressive weeds. Single and mixed plantings of winter wheat, clover, and chicory/plantain were sown after corn planting while establishing a hand-weeded and weedy control. From 2021 to 2023, we found the triple mixture to lower weed biomass at the end of the season while also having the highest total relative yield, indicating cover crops in this mixture accumulated more biomass than their single plantings. No corn yield was collected in 2022, but low nutrients impacted corn yield in 2021, which was lower overall compared to the 2023 corn yield. Within 2021, weed pressure played a significant role in reducing corn yield, but the single planting of clover and winter wheat had higher yields than the control left weedy and comparable to the control with no cover crops or weeds. In 2023 all cover crop treatments and controls did not differ significantly indicating these corn varieties have a potential higher tolerance from weed or cover crop competition. Indigenous growers now have data relevant to their corn varieties and their goals to preserve their traditional food systems. The trial and error from these experiments was integral to the relationship building between UW-Madison and our Indigenous partners, creating a shared learning environment to better understand sustainable farming practices. From this project, we have developed a framework to guide agricultural research with Indigenous communities centered on the principles of traditional Indigenous farming.
Speakers
ES

Erin Silva

UW-Madison
Co-authors
DH

Daniel Hayden

UW-Madison
NA
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Lehua Suite

4:45pm HST

RHIZ - Root Characterization Analysis of Navajo Peach Seedlings
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Southwest Native American Tribes, such as the Navajo, Hopi, and Pueblo, have grown peaches at least since the early 1600’s, making them a nutritionally and culturally important food source. Historic management practices consisted of reduced irregular irrigation of sandy to sandy loam soils with no fertilizer additions, no pruning, and no fruit thinning. Recent research indicates germinated peach seedlings from seed sourced from a Navajo orchard in Utah are more drought resistant when compared to direct seeded ‘Lovell’ seedlings, and container transplanted ‘Lovell’ seedlings. The purpose of this study was to characterize the Navajo seedlings’ root distribution after direct seeding to better understand their rooting dynamics with regular irrigation and no pruning. All trees were direct seeded in May 2018 and destructively sampled in May 2022. Three trees from each Navajo and ‘Lovell’ treatment were destructively harvested to determine above ground biomass. Root distribution (location relative to the trunk and depth in the soil profile) was determined using a soil core sampling technique. Soil cores were taken in a radial array around the tree, and tree roots (small, medium, large) were separated from the soil cores in the field, before drying and weighing. After the cores were extracted, the remaining root system was excavated, air dried for 10 days, then weighed and photographed. The main effect and interactions of tree type, sampling location, and depth were tested by analysis of variance. The Navajo seedlings had a more extensive root system, including more roots in the grass alleyways, than Lovell seedlings indicating a more competitive root system. There were also qualitative differences in root types between Navajo and ‘Lovell’ in the occurrence of lateral primary roots, sinker roots or fibrous roots. The results of this research will be utilized to determine the Navajo seedlings’ potential for becoming a viable rootstock for the fruit industry.
Speakers
RW

Reagan Wytsalucy

Utah State University
Native American food crops of the Southwest.
Co-authors
BB

Brent Black

Utah State University
NA
DD

Daniel Drost

Retired
NA
GC

Grant Cardon

Utah State University
NA
Tuesday September 24, 2024 4:45pm - 5:00pm HST
South Pacific 4

4:45pm HST

VGBR 1 - Progress and Insights Into Downy Mildew Resistance Mapping Efforts in Spinach
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Spinach (Spinacia oleracea) is a popular leafy vegetable crop in the US, particularly for the fresh market baby leaf spinach. However, downy mildew (DM), caused by the obligate oomycete Peronospora effusa, poses a significant challenge to spinach cultivation in California and Arizona as it reduces the quality and yield of spinach. This is particularly concerning given that the two production areas contribute over 85% of the total fresh market spinach in the US. The emergence of new races of P. effusa, with nineteen races reported and fourteen identified in the last two decades, presents a persistent threat as new races and variant isolates can overcome the existing resistance in commercially deployed cultivars. Furthermore, over 50% of the spinach market is organic production, so utilizing host genetic resistance is a crucial disease management strategy. To combat this challenge, we conducted screenings of germplasm, cultivars, and multi-parent progeny populations in greenhouse conditions to identify resistant sources and genomic regions associated with resistance to multiple races of P. effusa (specifically race 5, 13, and 16). The spinach population panel was sequenced utilizing genotyping by sequencing (GBS), low coverage resequencing, and 10x coverage whole genome resequencing (WGR) to generate single nucleotide polymorphisms (SNP) markers. Subsequently, genetic analysis was performed using disease phenotype response data obtained and SNP markers for the identification of resistance-associated SNP markers and candidate resistance genes. The molecular analysis and mapping efforts have yielded valuable insights into the basis of downy mildew resistance in spinach, providing essential molecular tools to facilitate breeding for disease resistance. This work will summarize the updated findings from these efforts. This work will enhance our understanding of resistance mechanisms, which will contribute to developing more effective breeding strategies, increasing selection gains and breeding efficiency in spinach.
Speakers
GB

Gehendra Bhattarai

University of Arkansas
Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
BM

Beiquan Mou

USDA-ARS, Crop Improvement and Protection Research Unit, Salinas, CA, 93905, USA
NA
JC

James C Correll

University of Arkansas
NA
Tuesday September 24, 2024 4:45pm - 5:00pm HST
South Pacific 3

4:45pm HST

WUM 2 - Microbial Community Composition and Accumulation Of Biofilms In Irrigation Pipes Using Nutrient Solutions with Different
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Biofilms clog irrigation systems, thus affecting water use efficiency, crop yields, and production costs. Microbial attachment and subsequent biofilm accumulation is influenced by the irrigation water quality and materials used in the design of water distribution systems. Therefore, the goal of this research was to evaluate if the pipe material and the load of organic matter in nutrient solutions affected biofilm accumulation, microbial community composition, and emitter performance. Nutrient solutions had 0, 30, 60, and 120 mg·L-1 peat particles under 150 µm in diameter and flowed through pipe loops made of polyvinyl chloride (PVC) and polyethylene (PE). The emitters were pressure compensated drippers with anti-drain mechanism and a nominal discharge of 2 L·h-1. Heterotrophic plate counts and biofilm dry mass were used as indicators of biofilm accumulation. DNA was extracted from the biofilm then sequenced for bacterial community composition analysis. The surface of new and post-biofilm pipes was characterized by measuring hydrophobicity and roughness to evaluate the effects of biofilm on the pipe’s surface. None of the emitters clogged, but there was an increase in discharge with 60 and 120 mg·L-1 peat. This observation suggests that the particles and biofilm accumulation affected the operation of the emitters’ anti-drain mechanism. The pipe material had more influence on the accumulation and bacterial community composition of biofilms than the organic load of the nutrient solution. Overall, biofilm accumulated more on PVC pipes than on PE pipes. The hydrophobicity of PVC pipes decreased, and roughness of PVC and PE pipes increased after biofilm colonization. These results suggest that the characteristics of the pipes can influence and be influenced by biofilms and therefore affect the risk of clogging. Our results also suggest that biofilms establish better on materials that biodegrade easy and that biofilm changes the roughness of PVC pipes which may further affect pipe longevity.
Speakers
JC

Juan Cabrera Garcia

University of Missouri
Co-authors
RR

Rosa Raudales

University of Connecticut
Tuesday September 24, 2024 4:45pm - 5:00pm HST
Nautilus 1

4:59pm HST

Technology (TECH) - Poster
Tuesday September 24, 2024 4:59pm - 6:00pm HST
Growth-promoting Bacteria in Improving the Biophysical Parameters of Cherry Tomatoes (Solanum lycopersicum L.)  - Henrique Oliveira
Promoting Controlled Environment Agriculture Activities At Campus-Wide Events - Kent Kobayashi
Rapid Detection of Herbicide-Resistant Weeds Utilizing Novel Full-Spectrum Imaging and a Hyperparameter-Tuned Convolutional Neural Network (CNN) - Pauline Victoria Estrada
Puʻuhonua Kauluwehi: Maui Wildfire Rapid Response Strategies for Agroecosystem Resilience and Community Well-Being - Nicolette van der Lee
Enhancing Hot Pepper Quality and Yield through Smart Irrigation Strategies - Harmandeep Sharma
Spraying Drone Efficiency: A Comparative Study of Application Rate and Surfactant Addition - Lucas Sales
Moderator
NV

Nicolette van der Lee

Program Manager, University of Hawaii Maui College
Tuesday September 24, 2024 4:59pm - 6:00pm HST
South Pacific 2

5:00pm HST

TECH - Growth-promoting Bacteria in Improving the Biophysical Parameters of Cherry Tomatoes (Solanum lycopersicum L.)
Tuesday September 24, 2024 5:00pm - 5:10pm HST
As a strategy, the use of plant growth-promoting bacteria (PGPB) in agriculture has stood out because they interact symbiotically with plants, promoting their growth directly or indirectly. The objective of this study was to evaluate the effects of the effects of inoculation with Bacillus subtilis ATCC 23858 and Burkholderia seminalis TC3.4.2R3 on the biopshycal characteristics of the plants, technological attributes of the fruits, and productivity of common cherry tomatoes . The experiment was arranged in a randomized block design with three treatments: i) inoculation with Bacillus subtilis ATCC 23858; ii) inoculation with Burkholderia seminalis TC3.4.2R3; and iii) non-inoculation, with eight replications. The data were subjected to analysis of variance (ANOVA) using the F-test followed by the Tukey test (P
Speakers
HO

Henrique Oliveira

Goiano Federal Institute
Co-authors
JL

Jhon Lennon Bezerra da Silva

Goiano Federal Institute
NA
MM

Marcio Mesquita

Federal University of Goiás
MV

Marcos Vinicius da Silva

Federal Rural University of Pernambuco
NA
PJ

Priscila Jane Romano G Selari

Goiano Federal Institute
NA
TD

Thiago Dias Silva

Goiano Federal Institute
NA
WD

Wesley de Melo Rangel

Goiano Federal Institute
NA
Tuesday September 24, 2024 5:00pm - 5:10pm HST
South Pacific 2

5:00pm HST

EcoPhys 1 - Trade-Offs in Reproductive Traits and Buds' Freezing Survival Strategies Among Prunus Species
Tuesday September 24, 2024 5:00pm - 5:15pm HST
The adaptation of perennial species to winter freezing temperatures is crucial for their reproductive success and has led to the evolution of diverse survival strategies to mitigate freezing damage. Bud survival is essential for species reproduction and fruit production, as buds carry the dormant flower primordia that will bloom in the next growing season. We studied two freezing survival mechanisms: deep supercooling (DS) and extraorgan freezing (EOF). Deep supercooling involves physical or structural changes that prevent ice nucleation in florets and meristems by sequestering small amounts of water. When the critical nucleating temperature for this sequestered water is reached, ice propagation is rapid, and cellular damage is lethal. Extraorgan freezing causes a gradual dehydration of inner bud tissues, driven by the vapor pressure deficit from extracellular ice formed in bud scales. Despite existing knowledge, the survival benefits of species undergoing deep supercooling, considered a limited strategy compared to extraorgan or extracellular freezing, remain unclear. Similarly, how adaptation to freezing impacts reproductive traits in woody species is not well understood. We focused on the Prunus genus for its dual survival strategies and productive and ornamental value. This study, conducted on six Prunus species at the Arnold Arboretum in Boston, MA, spanned three developmental stages: leaf drop in fall, dormancy in winter, and pre-bud swell in spring. Data encompassed phenology, vascular tissue development, flower primordia size, differential thermal analysis, controlled freezing tests, and characteristics of flowers, fruits, and seeds. Results indicated that DS Prunus species delay vascular tissue development and grow larger flower primordia from fall compared to EOF species. Conversely, EOF species bloom later, producing more and smaller flowers and fruits in a shorter time than DS species. In summary, in the Prunus genus, DS species appear to trade a lower temperature threshold for pre-forming fewer, larger flower primordia per bud, enabling earlier blooming and more efficient use of the growing season to develop larger fruits in contrast to EOF species.
Speakers
avatar for Camilo Villouta

Camilo Villouta

Assistant Professor, University of Rhode Island
Tuesday September 24, 2024 5:00pm - 5:15pm HST
Coral 1

5:00pm HST

ORGH 1 - Bridging the Gap: Culinary Breeding Network Facilitates Collaboration in Variety Development
Tuesday September 24, 2024 5:00pm - 5:15pm HST
In the past decade, there has been a significant rise in initiatives by public sector programs, independent seed companies, and farmer-breeders aimed at developing organic varieties in the United States, particularly targeting farmers engaged in direct-to-consumer sales. Flavor has emerged as a paramount trait for these farmers, driving collaborative breeding efforts involving a diverse array of stakeholders, including farmers selling to restaurants, farmers markets, and CSAs, as well as chefs at farm-to-table establishments, and plant breeders focusing on organic systems. Since seed regulations in the US allow seed to be sold without a registration process, varieties identified as well-suited and high-quality by collaborating farmers and chefs can quickly become available commercially. While diversified organic vegetable farmers often prefer not to produce their own seed, they wish to be actively engaged in the selection processes and support plant breeders focusing on organic systems (Hubbard and Zystro, 2016). The Culinary Breeding Network (CBN) strives to bridge the gap between plant breeders and consumers by facilitating unique opportunities for stakeholders to assess in-development vegetable and grain cultivars, share insights, and actively contribute to variety development. CBN's outreach events span across various regions, including Oregon, Washington, Hawaii, Wisconsin, New York, and Italy, focusing on identifying desirable traits, discerning consumer preferences, tailoring varieties to organic farms and palates, and celebrating local foods. These participatory public gatherings provide breeders with invaluable input rarely accessible otherwise. By integrating culinary professionals, farmers, and consumers into the breeding process, breeders gain deeper insights into preferred traits while also fostering broader awareness and understanding of organic plant breeding. CBN impact is evaluated through post-event surveys completed by attending farmers, chefs, distributors, retailers, and consumers. In 2020, 144 Variety Showcase surveys were collected, with 96% expressing intentions to disseminate gained knowledge, reaching an estimated >2,075 individuals in person and >258,000 through social media. Furthermore, 81% indicated that newfound knowledge would influence their work through expanded networks (34%), revised buying practices (25%), and informed decision-making (41%), among other outcomes such as forging new collaborations and partnerships. Participating breeders, seed companies, and farmers report moderate to significant positive effects to CBN, with 75% reporting impact on their business operations. Notably, CBN's most valued impact lies in "creating buzz in the community around specific vegetables and varieties" (48%) and "facilitating collaboration among breeders, growers, chefs, and consumers" (35%). Remarkably, 80% of respondents stated they had commenced growing a variety following a CBN event.
Speakers
LS

Lane Selman

Oregon State University
Tuesday September 24, 2024 5:00pm - 5:15pm HST
Lehua Suite

5:00pm HST

RHIZ - Characterizing Root Dynamics and Phenology of Hops in a Subtropical Climate Using an In-situ Root Imaging System
Tuesday September 24, 2024 5:00pm - 5:15pm HST
In Florida's subtropical climate, photoperiod manipulation facilitates a unique production system for hops (Humulus lupulus L.), an important crop for the brewing industry, with two growth cycles per year. The spring season spans from mid-February to early June, immediately followed by the fall season, which concludes in late November. With contrasting climatic conditions, plant phenology, yield, and cone quality differ dramatically between the two growing seasons. To gain insights into the roles of roots in the seasonal differences in plant phenology and performance, we characterized root dynamics and phenology of 'Cascade' hops grown in West Central Florida using an in-situ root imaging system. The soil at the study site was Myakka fine sand with 97% sand. Plants were grown on a 4.5 m V-trellis system, and data were collected over 2 years upon transplanting. Minirhizotron tubes were installed at varying distances (0, 30, and 60 cm) from the planting hill perpendicularly to the row to capture biweekly root images up to a depth of 84 cm. These images were processed using WinRhizo Tron software to measure various root morphological parameters, including total root length, projected area, surface area, volume, and the longest root. Notably, hop roots showed rapid elongation, reaching a depth of 84 cm, and expanding up to 60 cm from the hill center within one month after establishment under subtropical conditions. However, the primary, larger in diameter tap roots exhibited signs of decay after 5 months, culminating in complete mortality within 15 months following their establishment. Interestingly, the phenological stage of cone development induces a proliferation of new root growth, although temporary, with these ephemeral roots having a lifespan limited to approximately 3 months. These results can provide insights into the shoot-root interactions and help improve fertilizer, water, and ground cover recommendations, ultimately optimizing hop production in Florida's unique subtropical system.
Speakers
AJ

Alvaro J. Bautista

University of Florida
Co-authors
SA

Shinsuke Agehara

University of Florida
Tuesday September 24, 2024 5:00pm - 5:15pm HST
South Pacific 4

5:00pm HST

VGBR 1 - Screening Baby Leaf Salad Greens for Downy Mildew Resistance
Tuesday September 24, 2024 5:00pm - 5:15pm HST
Downy mildew presents major challenges to baby leaf salad greens production in California. Baby kale (Brassica oleracea) particularly holds substantial economic value in the region with a crop value of over $12 million in 2022. Downy mildew, caused by the oomycete pathogen Hyaloperonospora brassicae, infects baby kale resulting in leaf chlorosis, necrosis, and sporulation, rendering affected leaves unmarketable. Resistant varieties offer an effective solution, reducing the need for pesticides and promoting sustainable disease management in baby kale production. This research aims to screen baby kale plant materials (accessions) for resistance to downy mildew isolates from across California. Initially, 212 baby kale accessions were evaluated for resistance using a downy mildew isolate from Gilroy, CA. Plants were inoculated with downy mildew spores and incubated in high-humidity conditions before being evaluated for disease symptoms. The initial screening indicated an average disease severity of 31%. From this screening, 50 accessions showing the lowest disease severity were further screened against seven additional downy mildew isolates. Among the subset of 50 accessions, disease severities ranged from 0.1% to 7.6%. Notably, nine accessions consistently exhibited a disease severity of 0%, and 17 accessions maintained disease severities of 0.1% or 0.2% across all seven isolates, making an elite secondary subset of accessions. Ongoing research includes replication trials with a secondary subset of accessions and the two most virulent and weak downy mildew isolates. This research will identify resistant baby kale varieties, providing valuable insights for breeders and improving downy mildew management practices in kale production systems.
Speakers
SD

Shunping Ding

Associate Professor, California Polytechnic State University
Co-authors
EL

Emily Locke-Paddon

California Polytechnic State University
NA
LT

Lauren Taylor

California Polytechnic State University
NA
MF

Marco Fernandez

California Polytechnic State University
NA
Tuesday September 24, 2024 5:00pm - 5:15pm HST
South Pacific 3

5:00pm HST

WUM 2 - ATP vs Petrifilm: Techniques to Quantify Microbial Communities for Water Quality Analysis
Tuesday September 24, 2024 5:00pm - 5:15pm HST
Traditional methods of microbial quantification for irrigation water using colony counts from agar culture require dedicated laboratory space and trained personnel, making them less suitable for on-site application by horticulture growers. Dehydrated Petrifilm™ culture plates are a simpler method than agar, but are still time-consuming and require 2-3 days to culture. Adenosine Triphosphate (ATP) tests may provide an easy and reliable method for quantifying microbes in water that is more rapid than culturing microbes. The objective was to compare ATP measurements against colony counts cultured using Petrifilm™ for assessing microbial water quality. Lake water was recirculated through an ozone system until a target oxidation reduction potential (ORP) of 700 mV was reached. Samples were collected at the following ORP intervals: control, 300 mV, 400 mV, 500 mV, 600 mV, and 700 mV. Samples were plated for aerobic bacterial counts and yeast and mold counts using Petrifilm™ culture plates. Samples were also analyzed for free and total ATP concentration using the Hygiena EnSURE luminometer and its accompanying free and total ATP swabs. Microbial ATP was calculated by subtracting free ATP from total ATP. Results showed a consistent decrease in bacterial and fungal counts with increasing ORP using Petrifilm™ culture plates. At 700 mV ORP, there was 99.5% reduction of bacterial colony counts and 92.8% reduction of fungal colony counts from the initial. Similarly, a decreasing trend was observed for free, total, and microbial ATP concentration with increased ORP levels. There was a 97.5 % reduction of microbial ATP from the initial concentration at 700 mV ORP. A positive correlation was observed between microbial ATP measured with the luminometer and bacterial counts obtained from Petrifilm™. Integrating ATP quantification into routine monitoring practices could provide easy and rapid results and enhance the efficacy of microbial assessments in irrigation water.
Speakers
DT

Dharti Thakulla

University of Florida
Tuesday September 24, 2024 5:00pm - 5:15pm HST
Nautilus 1

5:10pm HST

TECH - Promoting Controlled Environment Agriculture Activities At Campus-Wide Events
Tuesday September 24, 2024 5:10pm - 5:20pm HST
How can we help students, the public, and stakeholders become familiar and engaged with controlled environment agriculture (CEA) and its benefits? Besides offering undergraduate courses such as TPSS 300 Tropical Production Systems and TPSS 491 Experimental Topics "Controlled Environment Agriculture" we sought other ways to accomplish this. The objective is to describe how we use displays about our CEA lab at campus-wide events to help inform audiences about CEA and its technology. Various events at the University of Hawaii at Manoa (UHM) enable colleges, departments, units, and individual laboratories the opportunity to showcase their programs, curricula, and research. At these campus-wide events, we set up table displays that explain CEA and highlight our CEA research. Our displays exhibit various aspects of the technology used in CEA such as LED (light-emitting diodes) lights, hydroponics, and greenhouse materials. We display high tech acrylic greenhouse coverings and walls, smart glass, photoselective shadecloths, and light spectrum control plastic films to show recent developments in greenhouse coverings. Hydroponic principles are explained through the use of micro-hydroponics, dwarf vegetables grown under LED lights, and hydroponic kits. A display using simulated Martian soils and LEGO® figures shows a Martian landscape with a plastic dome greenhouse with plastic vegetables growing inside. The audience gets to experience a hands-on working miniature grow tent, a replica of actual grow tents, to demonstrate how CEA experiments are conducted using grow tents with manually controlled red, blue, and white LED lights and fans. We have a shadecloth covered PVC pipe box with red and blue photoselective shadecloths and LED light placements on top, sides, and intracanopy to explain light spectrum and light placement. The Lunar/Martian greenhouse model displays an example of how plants could be grown on extraterrestrial bodies such as the moon and Mars. The display shows a cutaway view of a greenhouse installed below the soil surface for protection from radiation. Natural light is supplied with light pipes and artificial light is supplied with LEDs. Our lab’s table displays have been well received by people stopping by our tables. The campus events provide the opportunity for students to assist in staffing the tables and talking about CEA and their research. We also discuss CEA research opportunities provided by the UHM Undergraduate Research Opportunities Program (UROP) and the UHM Hawaii Space Grant Consortium Program.
Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
Co-authors
BN

Brylin Nelson

Univ of Hawaii at Manoa
NA
JK

Jonathan Kobayashi

University of Hawaii at Manoa
NA
Tuesday September 24, 2024 5:10pm - 5:20pm HST
South Pacific 2

5:15pm HST

EcoPhys 1 - Potential Genes Involved in the Adaptation of Potato to Long Term Heat Stress
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Heat stress is one of the most significant uncontrollable abiotic factors that affect potato plant growth, development, and tuber yield. While short-term acute heat stress experiments have produced considerable insights into the effects of heat stress on potato, there is a lack of information on the mechanisms involved in heat stress adaptation. Our recent studies demonstrate that under prolonged heat stress (35/25°C, day/night, for 3 weeks), newly developed leaves can maintain health and adapt to heat stress by modifying anatomy and physiology. Whereas, the leaves developed prior to heat stress (20/15 °C, day/night) on the same plant suffer (chloroses, senescence) from heat stress. We compared the gene expression in the youngest, fully expanded terminal leaflets developed under control and heat stress in two genotypes, Solanum tuberosum L. ‘Atlantic’ (ATL) and Solanum microdontum Bitter (MCD). As expected, several heat shock proteins (HSP) genes were upregulated in both genotypes. In addition, several desaturase genes were downregulated suggesting an increase in the saturation of membrane lipids may provide membrane integrity under heat stress. Our parallel physiological and anatomical studies have shown that adaptation to heat stress involves increase in stomatal density, lowering of leaf temperature via increased transpiration and maintenance of photosynthesis. Consistent with these results we found significantly regulated genes involved in ABA biosynthesis, photosynthesis, cell growth, expansion and patterning. These data offer insight into potential genes involved in heat tolerance in potato that may be useful in breeding for heat-tolerant potato varieties.
Speakers
JP

Jiwan Palta

UW Madison
Co-authors
AD

Alfonso DelRio

University of Wisconsin Madison
NA
JB

John Bamberg

University of Wisconsin Madison
NA
JS

Justin Schabow

University of Florida
NA
JM

Jyostna Mura

University of Wisconsin
NA
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Coral 1

5:15pm HST

ORGH 1 - Growing Urban Organic Farms in Iowa: New Initiatives and Support
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Urban agriculture, which encompasses both home use and commercial sales, has shown positive impacts on enhancing sustainable agriculture and food security, especially for disadvantaged and underrepresented citizens. The benefits of community gardens/farms have been found to be extensive, including improved quality of life and nutrition, enhanced economic security and environmental sustainability, entrepreneurship and employment, and community commitment. In a new Iowa State University (ISU) Extension and Outreach project, the ISU Organic Ag program (OAP) will be working with urban farms in Iowa to create a Community of Practice network that will promulgate best management practices and sharing of results among farmers and agency staff supporting this clientele group. Because the majority of urban farms use organic practices, these farms will be surveyed for critical pest issues; suitability of organic treatments for specific pests; and economic viability of these strategies. In addition, farmers will be queried on the potential for organic certification, including group certification. A statewide Urban Ag group, created in 2023, identified the following needs, based on urban farmers’ interests: Land access and utilization; Education and program access; Production needs, including managing soil health and irrigation; Food safety and food insecurity; and Business development. A Directory of Expertise in Urban Ag was developed to highlight six specialists focused on urban ag in Iowa at Iowa State University; four at federal agencies (NRCS, RMA, FSA), three in state and municipal government (IDALS, City of Des Moines); two at government-associated programs (SWCD), and eight at non-profit, non-governmental institutions (NGOs). Working with county Extension staff, Master Gardeners, 4-H, NRCS, SWCD, and urban ag NGOs and farmers, this project seeks to advance Urban Ag through: 1) Demonstration sites showcasing innovative nutrient and pest management techniques, bee keeping, food safety practices, and marketing; 2) Field Days held at key urban farm partners with adjoining Farmers’ Market tours; and 3) A series of webinars, videos and pamphlets covering these topics, and translated for Spanish, Burmese and Congolese audiences–the most prominent groups of immigrant urban farmers in Iowa. Evaluation will assess knowledge and behavioral change related to addressing key food security concerns in urban spaces, community well-being, and sustainability indicators, including soil and water quality.
Speakers
KD

Kathleen Delate

Iowa State University
Co-authors
JP

Josiah Pollock

Iowa State University
NA
KP

Karenna Petersen

Iowa State University
NA
RT

Robert Turnbull

Iowa State University
NA
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Lehua Suite

5:15pm HST

RHIZ - Effects of Reclaimed Water on Blueberry Seedling Growth and Root Morphology
Tuesday September 24, 2024 5:15pm - 5:30pm HST
A high percentage of agricultural production depends highly on groundwater irrigation. Groundwater depletion has been putting significant pressure on global water resources and food production. Using reclaimed water (RW) as an alternative source of irrigation water for crop production can mitigate the huge demand on groundwater resources. Blueberry plants are characterized by their preference for acidic soil conditions with a shallow, salt-sensitive root system. The alkaline and saline nature of RW necessitates an understanding of its suitability as irrigation water for blueberry production. We conducted a greenhouse rhizotron experiment to characterize root morphological responses of ‘Arcadia’ blueberry seedlings to RW. Four irrigation water treatments were implemented: 100% well water (WW), 100% deionized water (DW), a blend of 50% DW/50% RW, and 100% RW. These treatments were applied to rhizotron boxes filled with 50% sand and 50% pine bark mixed uniformly by volume. Root morphological variables, stem diameter, plant height, canopy projected area, and plant physiological variables were examined biweekly. Soil and plant tissue nutrient contents and plant biomass were examined at the end of the experiment. Water quality was slightly alkaline with pH values of 7.8 for 100% WW and 100% DW, and 7.7 for 100% RW. Electrical Conductivity (EC) values varied among the treatments, with 0.428 dS/m for 100% WW, 0.338 dS/m for 100% DW, and 0.769 dS/m for 100% RW. Initial soil mix pH at the beginning of the experiment was 6.8. Our preliminary findings indicate no significant difference in root elongation, plant above-ground biomass and leaf chlorophyll index among the four irrigation treatments (p > 0.05). A significant difference was observed between DW and WW for plant stem diameter and height (p > 0.05), possibly attributed to blueberry plants’ sensitivity to salt. The soil mix pH had risen to 7.8 for all the treatments at the end of the experiment. Our preliminary interpretation suggests that 100% RW does not adversely affect young blueberry plants growth parameter over the short-time period of the experiment. That indicates that RW can be a promising alternative of irrigation. Existing literature indicates that blueberry plants have the ability to adopt to irrigation water EC level of up to 2 dS/m, while the measured EC of 100% RW was 0.77 dS/m, it appears that the blueberry plants didn’t reach to the stress level that could significantly affect their growth parameters. We believe the experiment duration was insufficient to observe the high pH symptoms.
Speakers
YS

Yasmeen Saleem

University of Florida
PhD student
Co-authors
DK

Davie Kadyampakeni

University of Florida
NA
Tuesday September 24, 2024 5:15pm - 5:30pm HST
South Pacific 4

5:15pm HST

VGBR 1 - Detection of Novel Lettuce Fusarium Wilt Pathogenic Variants in California
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Fusarium wilt (FW), caused by the soilborne fungus Fusarium oxysporum f.sp. lactucae (FOL), is an economically important disease of lettuce (Lactuca sativa L.). Four pathogenic races of FOL have been reported, though only race 1 is known to exist in the United States. Recently, California coastal lettuce growers have experienced changes in the severity and incidence of FW. Some race 1-resistant cultivars have exhibited susceptibility, whereas some susceptible cultivars have displayed a reduction in disease severity. In order to determine whether such changes in disease patterns are responses to potentially novel variants, we collected FW symptomatic plant samples from commercial fields in Salinas Valley and Santa Maria, recovered the fungus, and conducted a series of pathogenicity tests in controlled conditions over two years (2022 and 2023) using a standard set of FOL race differentials. Pathogenicity tests revealed two new FOL variants, Fol621s and 916, that elicited novel disease reaction patterns on the standard differentials which have never been reported in the United States or other parts of the world. Isolate 916 incited severe FW on race 1-resistant ‘Costa Rica No. 4’, whereas Fol621s was less virulent on race 1-suceptible ‘Banchu Red Fire’. This study provides valuable information critical for the development of FW management strategies, including broad-spectrum resistance breeding efforts against multiple FOL races and novel variants.
Speakers Co-authors
AP

Alexander Putman

U.C. Riverside
NA
FM

Frank Martin

USDA-ARS
NA
NL

Ningxiao Li

USDA-ARS
NA
Tuesday September 24, 2024 5:15pm - 5:30pm HST
South Pacific 3

5:15pm HST

WUM 2 - Water use and crop coefficients for outdoor nursery ornamentals in 15-gal containers
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Nurseries and greenhouses in California face challenges of limited water supply and increased scrutiny from water quality regulators. Improving irrigation efficiency thus minimizing irrigation runoff are the main strategies to save water and comply with regulations. Evapotranspiration-based (ET) methods that make use of weather station data has the potential to substantially improve efficiency. In California, a statewide network maintained by DWR CIMIS project is widely used. However, crop-specific coefficients to calculate irrigation needs from weather data are not widely available in the nursery industry, particularly for large (15-gal and up) containers. In this project we measured water use and developed crop coefficient for 15-gal trees, one low water user (Olive, Olea europaea) and two high water users (Sycamore, Platanus acerifolia and Ficus microcarpa) with different canopy architectures. Container weight was measured with load cells (Omega LC103B, a weighing device similar to a scale), with values logged every minute by a Campbell Scientific data logger (CR1000X). Daily water use was calculated as the difference in weight from after each irrigation to before the following one. Local CIMIS reference ET was used to calculate crop coefficients. Tree water use yielded crop coefficients averaged 1.19 for Ficus; 0.57 for Olive and 1.21 in Sycamore during fall 2023 before defoliation started to occur for Sycamore in mid-October. Olive and Ficus defoliated through winter reaching the lowest crop coefficient in March 2024 when the coefficient was 0.42 for Ficus; 0.22 in Olive and 0.12 in Sycamore. Crop coefficients were substantially lower than those presented by Burger et al., 1987. for similar woody ornamentals grown in 1-gal containers. The difference is that Burger’s crop coefficients were calculated using the container surface area, while we used the (larger) block area divided by the number of containers. While less meaningful from a plant physiology point of view, a block-based crop coefficient is more useful for irrigation management and more similar to the crop coefficient calculation in field crops, grape vines and fruit trees. Results from our method can be converted to Burger et al. method by dividing by interception efficiency (i.e. cumulative container surface area divided by irrigation block area).
Speakers
avatar for Gerry Spinelli

Gerry Spinelli

University of California Cooperative Extension
Irrigation management in nurseries and greenhouses
Co-authors
CS

Chris Shogren

University of California Cooperative Extension Los Angeles
Tuesday September 24, 2024 5:15pm - 5:30pm HST
Nautilus 1

5:20pm HST

TECH - Rapid Detection of Herbicide-Resistant Weeds Utilizing Novel Full-Spectrum Imaging and a Hyperparameter-Tuned Convolutional Neural Network (CNN)
Tuesday September 24, 2024 5:20pm - 5:30pm HST
Every year, farmers around the world lose more than $95 billion from uncontrolled weed infestation. Herbicide-resistant weeds, also known as “superweeds”, are fast becoming a significant part of this weed problem and are a significant threat to crop production and food security. Late detection of resistant weeds leads to increasing economic losses and severe environmental damage. Traditionally, genetic sequencing and herbicide dose-response studies are used to detect herbicide-resistant weeds, but these are expensive and slow processes. To address this problem, an AI-based superweed identifier program (SIP) was developed to quickly and accurately distinguish herbicide-resistant from susceptible chickweed (Stellaria media). A regular camera was converted to capture light wavelengths from 300 to 1,100 nm. These full spectrum images were used to develop a hyperparameter-tuned convolutional neural network (CNN) model utilizing a “train from scratch” approach. This novel approach exploits the subtle differences in the spectral signature of resistant and susceptible chickweed plants as they react differently to herbicide treatments. The SIP was able to identify resistant chickweed to acetolactate synthetase (ALS) inhibitor herbicides as early as 72 hours post treatment at an impressive accuracy of 85%. It has broad applicability due to its ability to distinguish resistant from susceptible chickweed plants regardless of the type of ALS herbicide or dosage rate used. Utilizing the superweed identifier program will allow farmers to make timely interventions and develop more effective and safer weed management practices. This can optimize yield, reduce herbicide use, minimize environmental harm, prevent herbicide-resistant weed proliferation, and improve overall public health.
Speakers
PV

Pauline Victoria Estrada

Student, Clovis North High School/Fresno State University
Co-authors
AS

Anil Shrestha

Fresno State University
NA
Tuesday September 24, 2024 5:20pm - 5:30pm HST
South Pacific 2

5:30pm HST

TECH - Puʻuhonua Kauluwehi: Maui Wildfire Rapid Response Strategies for Agroecosystem Resilience and Community Well-Being
Tuesday September 24, 2024 5:30pm - 5:40pm HST
The Puʻuhonua Kauluwehi project aims to develop a rapid response to the recent Maui wildfires by collaboratively establishing a network of biocultural refuges supporting the cultivation of native plants to accelerate landscape-scale agroecological resilience, food security and community well-being strategies. Puʻuhonua Kauluwehi is a Hawaiian phrase describing regenerative agroecosystem areas that provide shelter for native vegetation, attract native birds and insects, and serve as a source of thriving launching points to revegetate the landscape through community engagement. In Hawaiʻi, establishing biocultural refuges is even more critical as the unique ecosystems of the islands continue to come under threat from invasive species, drought, commercial development, lack of ecosystem management and are more at risk due to the dependence on imported response and aid resources from the mainland as demonstrated by the devastating impact of the Maui wildfires in August 2023. The project’s specific objectives are to: (1) Provide applied research and GIS mapping services that integrate water quality testing, soil testing and native plant and tree cataloging in one accessible database for the growing coalition of local agricultural and conservation organizations responding to the wildfires; (2) Develop strategies to ensure all children, youth, and adults have access to abundant local food during and after wildfire disasters through a network of seed orchard, seed bank, nursery and food hub partners; and (3) Design extension and non-formal community education initiatives to address the health and well-being of children, youth, and adults affected by wildfire disasters through work-based agroecosystem and stewardship training in the Kauluwehi Biocultural Garden for 300 participants. The Puʻuhonua Kauluwehi restoration project, led by University of Hawaii Maui College, will share initial outcomes of launching a technology platform to connect critical nodes of the Maui wildfire response into a thriving network that will serve as a social-ecological incubator for the positive impact of vibrant and culturally authentic landscapes and redefine the value of agroecosystems in Maui’s unique context for disaster recovery.
Speakers
NV

Nicolette van der Lee

Program Manager, University of Hawaii Maui College
Tuesday September 24, 2024 5:30pm - 5:40pm HST
South Pacific 2

5:30pm HST

EcoPhys 1 - Species-specific Differences in Leaf Photosynthetic Rate when Substituting Far-red Light for PAR Photons
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Phosynthetically active radiation (PAR; 400 – 700 nm) is widely acknowledged as essential for photosynthesis in plants. However, recent research has revealed the significant contribution of far-red photons (FR; 700 – 750 nm) to photosynthetic processes, particularly when present alongside PAR. While previous studies have primarily focused on whole-plant gas exchange, limited research exists on leaf-level replication of these findings. In this preliminary study, we investigated leaf gas exchange in five field-grown crop species using A/Ci curves. We exposed the leaves to equal proportions of blue, green, and red light at a photon flux density of 1000 µmol·m-2·s-1 and replaced varying percentages (0%, 15%, or 30%) of these photons with FR. Our hypothesis, based on previous whole-plant studies, was that all species would exhibit similar photosynthetic rates (Pn) across different FR treatments. Contrary to our hypothesis, we observed species- and cultivar-specific variations in leaf-level Pn with FR treatments. For instance, strawberry and green leaf lettuce exhibited decreased Pn with increasing FR, while apple and Swiss chard showed increased Pn. Red leaf lettuce maintained consistent Pn levels. Despite these differences, the overall trends across CO2 concentrations remained consistent regardless of FR levels. Considering that direct sunlight naturally contains FR equivalent to approximately 18% of PAR, and our crops were grown in open-field conditions, our findings suggest a species-specific capacity to utilize FR in photosynthesis. These findings are preliminary, but data is being collected to examine species responses throughout a full growing season.
Speakers
JE

John Ertle

PP Systems
NA
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Coral 1

5:30pm HST

ORGH 1 - Metabolomic Analysis Provides Novel Insight Into the Evaluation of Organic Tomato Fruits
Tuesday September 24, 2024 5:30pm - 5:45pm HST
A gradual shift in the evaluation of crop quality has taken place, led by analytical scientists with the advancement of instrumentation and system-based technology (system biology). Metabolomics, one of the emerging omics techniques, provides a complete and unbiased chemical analysis within an organism. Information obtained through metabolomic analysis may range from identifying beneficial compounds for human health to toxicants, can help solve challenges faced by the agricultural industry. Current phytochemical studies focusing on organically-grown crops have typically focused on individual compounds or classes of compounds that may be affected by production practices. This study compared metabolomic profiles between organic and conventionally-grown tomato (Solanum lycopersicon) fruit to systemically access the quality and nutritional value of tomatoes under different growing conditions. Two tomato cultivars (‘Estiva’ and ‘Tomimaru Muchoo’) were grown with three different treatments (organic field, organic high-tunnel, and conventional field) and were assessed for metabolomic analysis using gas chromatography‒mass spectrometry (GC‒MS) and liquid chromatography‒mass spectrometry (LC‒MS). Target metabolites included various primary and secondary metabolites covering a wide range of metabolic pathways, involving citrate cycle, pyruvate metabolism, amino acid biosynthesis, alkaloids biosynthesis, shikimate pathway, salicylic acid pathway, plant hormone biosynthesis, phenylpropanoid biosynthesis, flavone, flavonol, and flavonoid biosynthesis, anthocyanin biosynthesis, and so on. Differentially expressed metabolites (potential biomarkers) between organic and conventional tomatoes were selected, and a core metabolic network was identified by pathway enrichment analysis. Major variations between groups were observed in the network related to plant secondary metabolisms (e.g., plant defense signaling). This is likely due to varying amounts of external stresses between organic and conventional tomatoes by the difference in pesticide input. The organic high-tunnel group also showed some distinct metabolic responses within the secondary metabolisms, probably because of its unique growing conditions. The selected biomarkers and identified metabolic network provided insights into biochemical processes influenced by different cultivation methods. This work will contribute to the evaluation of organic farming practices in the US.
Speakers
JK

Jashanpreet Kaur

The University of Georgia
Co-authors
JH

Joon Hyuk Suh

The University of Georgia
NA
KC

Kate Cassity Duffey

The University of Georgia
NA
TC

Timothy Coolong

The University of Georgia
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Lehua Suite

5:30pm HST

VGBR 1 - Unraveling Gene Regulation on the Interaction of Lettuce (Lactuca sativa L.) and Xanthomonas hortorum pv. vitians Causal Agent of Bacterial Leaf Spot.
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Bacterial leaf spot (BLS) of lettuce is a sporadic and destructive foliar disease that poses an economic threat to farmers, particularly those within Florida due to the subtropical environmental conditions. The disease is caused by the bacteria Xanthomonas hortorum pv. vitians (Xhv), which has three races. There are no chemical interventions that can effectively control this pathogen, creating a significant challenge for farmers to manage BLS. Additionally, most commercial lettuce cultivars are susceptible to BLS, emphasizing the need to improve host resistance. Resistance to Xhv race-1 has been identified in heirloom lettuce PI 358001-1 and ‘La Brillante’, and PI 667690. To facilitate and accelerate modern plant breeding techniques and the introgression of resistance into new cultivars, the identification of resistance genes is crucial. However, a detailed description on how these genes is regulated in the lettuce genome remains unknown. To aid in the understanding of the interaction between lettuce and Xhv, a gene expression study was conducted. A total of 180 plants each of La Brillante (R), PI 358001-1 (R), PI 667690 (R), and Okeechobee (S) were grown in laboratory conditions for 21 days. Half of the plants were mock inoculated with buffer, and the remaining plants were inoculated with Xhv race-1 isolate L7. Leaf samples were collected at 24-, 72-, and 144-hours post-inoculation, and RNA was extracted for sequencing using the Illumina NovaSeq 6000 platform. The analysis of differentially expressed genes and their associated pathways revealed distinct reactions upon interaction with Xhv. Additionally, similar reactions were observed in other crops and their respective Xanthomonas pathovars, such as the upregulation of peroxidases, chitinases, and proteases, were observed between inoculated and mock-inoculated plants, such response was time point dependent. Primers will be designed and validated for these candidate genes using qPCR with additional time points to confirm their expression across key plant development stages. These findings provide valuable insights into the molecular resistance of lettuce to BLS, unlocking new opportunities for molecular breeding techniques, identification of chemical compounds within the plant that control BLS, and the development of new resistant cultivars. This knowledge will benefit not only the UF/IFAS lettuce breeding program, but also be disseminated to other research groups working to breed BLS-resistant lettuce cultivars.
Speakers
BM

Byron Manzanero

Horticultural Sciences Department, University of Florida
My name is Byron Manzanero a Ph.D. Candidate in plant breeding.
Co-authors
GS

German Sandoya

University of Florida
JM

Jesse Murray

University of Florida
NA
Tuesday September 24, 2024 5:30pm - 5:45pm HST
South Pacific 3

5:30pm HST

WUM 2 - Quantification of irrigation and stormwater runoff volume, sediment load, and nutrient load when producing nursery crops
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Container nurseries produce a high volume of operational water (OW) during irrigation and storm events. OW is irrigation return flow (IRF) and storm runoff that has traveled through crop production areas and could carry sediment and agrichemicals, making nurseries a potential contributor to nonpoint source pollution. OW is collected in retention reservoirs for treatment and reuse or allowed to leave the site. A monitoring program was conducted on five production areas (study catchments) with two different irrigation systems (i.e., overhead and spray stake) in two container nurseries located in the Midwestern USA (Central Lowland physiographic region). Total suspended solid (TSS), dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) in OW during storm and irrigation events. We found median event mean concentrations (EMCs) during irrigation events for TSS, DIN, and PO4-P were 131 mg∙L-1, 2.9 mg∙ L-1, and 1.2 mg∙ L-1, respectively. During storm events, DIN and PO4-P EMCs were similar to irrigation events; however, TSS EMCs were almost 8 times greater than those of irrigation events. The median daily TSS, DIN and PO4-P load per ha during storm events were 13.3 kg·ha−1·day−1, 82.3 g·ha−1·day−1 and 43.5 g·ha−1·day−1, respectively, which were 20, 3, and 4 times greater than those of irrigation events. The results indicated that the portion contribution of storm and irrigation for producing TSS was 86% and 14%, respectively. The results of this study can facilitate improved irrigation scheduling and help assess potential treatment options.
Speakers
JO

James Owen

USDA ARS
Jim Owens is a USDA-ARS Research Horticulturist located at the Application Technology Research Unit in Wooster, OH. Jim received his B.Sc. in Plant and Soil Science at the University of Kentucky, his M.Sc. in Environmental Science at the University of Rhode Island, and Ph.D. at North... Read More →
Co-authors
MN

Mohammad Nayeb Yazdi

Arlington County Virginia
NA
SL

Steve Lyon

The Ohio State University
NA
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Nautilus 1

5:40pm HST

TECH - Enhancing Hot Pepper Quality and Yield through Smart Irrigation Strategies
Tuesday September 24, 2024 5:40pm - 5:50pm HST
Hot peppers (Capsicum chinense) are attracting increasing attention due to their rich reservoirs of secondary metabolites, notably capsaicinoids, which are in high demand across various industries such as culinary, cosmetic, and pharmaceutical. Consequently, there has been a surge in the number of new pepper growers emerging throughout the United States. Despite ranking fifth in pepper production, North Carolina’s pepper cultivation remains smaller compared to other states known for hot pepper production. Additionally, the southern U.S. anticipates an increase in extreme weather events such as droughts and floods. Thus, there is a pressing need to identify the most suitable pepper cultivars and implement efficient production management practices tailored to local climatic conditions to maximize both crop production and quality. To address this need, the current study was conducted at Reid Greenhouse, North Carolina Agricultural
Speakers Co-authors
EK

Edmond Kwekutsu

North Carolina Agricultural and Technical State University
NA
GG

Gregory Goins

North Carolina Agricultural and Technical State University
NA
HS

Harjot Singh

North Carolina Agricultural and Technical State University
NA
WR

William Randle

North Carolina Agricultural and Technical State University
NA
Tuesday September 24, 2024 5:40pm - 5:50pm HST
South Pacific 2

5:45pm HST

EcoPhys 1 - Investigating Dormancy ​ and Germination Characteristics​ to Promote Restoration Success​ in the Northern Great Plains​
Tuesday September 24, 2024 5:45pm - 6:00pm HST
In wildlands, such as the prairies of the Northern Great Plains, environmental degradation has created the need for ecological restoration of native plants on the landscape. These ecological restorations require native seed. However, many seed-based restoration efforts fail in that they do not produce the desired vegetation. Lack of species-specific information on germination characteristics and dormancy of native seed could be contributing to these failures. Therefore, restoration practitioners and other users of native seed need germination and dormancy information for native species to improve outcomes. Our objectives in this study were to examine germination characteristics and seed treatments that best promote germination in plant species native to the Northern Great Plains and define dormancy classes for each of our study species. To meet these objectives and promote success in seed-based restoration, we conducted a germination experiment for 15 high-priority native forbs. Seeds were treated with four pretreatments (scarification, smoke, fertilizer, and a control), three stratification lengths (2, 4, and 8 weeks), and different temperature regimes. We examined the influence of each factor to determine the means of breaking dormancy and best planting practices. Our data indicated that a scarification treatment before planting Gaillardia aristata increased germination by over 19%. This data suggests that while the majority of our G. aristata seeds are non-dormant, a percentage are physiologically dormant. Our data also shows that Penstemon albidus is strongly influenced by temperature conditions, and the species requires a period of cold stratification to increase overall germination. This information will be used to develop best planting practices for government agencies and aid seed producers and distributors by offering seed storage and planting instructions matching the phenology of native plant species. This rigorous germination experiment can also be used as a model for other priority species and can be adapted to different ecoregions.
Speakers
BL

Bret Lang

Student, South Dakota State University
Co-authors
GC

Gregory Cooper

South Dakota State University
NA
LP

Lora Perkins

South Dakota State University
NA
Tuesday September 24, 2024 5:45pm - 6:00pm HST
Coral 1

5:45pm HST

VGBR 1 - Exploring Physiological Traits as Predictors of Heat Content in Chile Peppers (Capsicum annuum L.)
Tuesday September 24, 2024 5:45pm - 6:00pm HST
Chile peppers (C. annuum L.) are valued for their capsaicinoid content, which contributes to their pungency (heat) and has various health benefits, including anti-inflammatory and anti-cancer properties. Assessing photosynthetic efficiency through the LICOR-600 porometer/fluorometer (https://www.licor.com/env/products/LI-600/) provides insights into the physiological vigor of the plants. This study employs a comprehensive suite of machine learning models to investigate the correlation between photosynthetic efficiency (stomatal conductance and chlorophyll a fluorescence) and Scoville Heat Units (SHU) to predict the capsaicinoid content within 20 chile pepper varieties. Photosynthetic data were collected at two sites, Fabian Garcia Science Center and Leyendecker Plant Science Research Center, Las Cruces, NM, with readings taken from three different leaves of each of five plants per genotype. Capsaicinoid levels were quantified using High-Performance Liquid Chromatography (HPLC) for each variety. Correlation and principal component analyses (PCA) were implemented to discern the primary influencers on capsaicinoid production. Five predictive models were explored: Decision trees, Random forests, Ridge regression, LASSO Regression, and Support Vector Regression. Each model was applied to predict both total SHU values and categorical SHU labels (mild, hot, very hot). Among these, the decision tree model was the most superior, achieving an R² of 0.77. Initial findings indicate notable variability in photosynthetic activity and capsaicinoid concentrations across the varieties, suggesting a significant but complex relationship that may guide future genetic improvements. The challenges in modeling can be attributed to data collection constraints. Additionally, uniform growing conditions across all test plants might have limited the variability necessary for more definitive model differentiation. This analysis not only advances our understanding of the physiological and genetic factors affecting capsaicinoid content but also underscores the complexities of modeling agricultural traits under consistent environmental conditions. Future research should consider more frequent data collection and the introduction of environmental stressors to better capture the dynamics influencing capsaicinoid production in chile peppers. Key word: High-Performance Liquid Chromatography, Scoville heat unit, photosynthetic efficiency
Speakers
MI

Muhammad Ibrar Khan

New Mexico State University
Co-authors
DN

Dennis Nicuh Lozada

New Mexico State University
EK

Ehtisham Khokhar

New Mexico State University (NMSU)
Tuesday September 24, 2024 5:45pm - 6:00pm HST
South Pacific 3

5:45pm HST

WUM 2 - Water Supply Resilience Through Florida-Friendly Landscaping
Tuesday September 24, 2024 5:45pm - 6:00pm HST
Traditional irrigated landscapes and in particular turfgrass dominated landscapes are being challenged across the U.S. due in part to the demand on potable water supplies. So called “ornamental” turfgrass will be outlawed in Nevada by 2027 and efforts are underway in other areas of the desert southwestern states to do the same. Meanwhile, in these areas, aggressive turfgrass removal programs utilizing financial incentives are occurring. This dramatic change is due to water supply associated with the Colorado River and western water supply in general. In the eastern U.S. changes are occurring in new development in North Carolina warm season grasses are displacing cool season grasses in new landscapes. Accordingly the new trend is to install bermudagrass without irrigation. In Florida, numerous municipalities have or are adopting codes mandating a maximum of the landscaped area as 60% sprinkler irrigation, which means turfgrass, and in some municipalities as low as 20% of the landscaped area. The remainder of the landscaped area is filled with a mixture of microirrigated ornamentals, mulched area, or unirrigated turfgrass. Some newer developments are eliminating irrigated turfgrass altogether. The Florida-Friendly Landscaping (FFL) program is uniquely positioned to deliver education relevant to the radical change that is occurring in designed and built landscapes. Many local governments are adopting landscape codes that include or mandate FFL principles. This talk will discuss these trends along with the factors driving this cultural change of landscapes and in particular the use of turfgrass in landscapes. Additionally, the talk will focus on the challenges ahead for landscapes under water supply constraints and how they may impact nonpoint source pollution from urban areas.
Speakers
MD

Michael Dukes

Professor & Director, University of Florida
Tuesday September 24, 2024 5:45pm - 6:00pm HST
Nautilus 1

5:50pm HST

TECH - Spraying Drone Efficiency: A Comparative Study of Application Rate and Surfactant Addition
Tuesday September 24, 2024 5:50pm - 6:00pm HST
Current agricultural practices are facing several challenges because of the use of large and heavy machinery used in the fields. The benefits of covering large areas to meet the time of spraying crops is becoming questionable because the heavy machinery (large self-propelled boom sprayers) also can cause soil compaction and require large amounts of fuel and technical labor to be operated. Moreover, spraying drones are emerging as a pivotal technology in modern agriculture. They serve multiple purposes, from measuring and understanding fields using sensor and camera-captured images to acting as spray applicators for a wide range of products e.g.,including herbicides, pesticides, fungicides, and fertilizers. As a novel technology, spraying drones overcome some of the challenges faced by traditional methods. For instance, they can initiate applications in specific areas that require treatment, thereby avoiding issues like soil compression and unnecessary use of cultivated areas. This enhances precision while reduces losses in the field. However, defining application rate and the impact of adjuvant products is still scarce in previous studies. Therefore, in this study, we analyzed whether the coverage area is influenced by application rates and surfactant addition. The study was conducted in a carrot crop field. Water-sensitive papers were placed on the top leaf and at the bottom of the plants to quantify the coverage area. The measured area comprised a swath of 40 feet and a drone route of 100 feet. Measurements were performed in 9 crop-rows, each row with three hydrosensitive papers spaced in 33 feet apart. A multirotor spraying drone XAG P100Pro with Atomized Nozzles was used to apply spraying rates of 5 and 10 gallons per acre, both with and without surfactant addition. Results showed more coverage area on the top leaf than at the bottom of the plants. Similarly, when 10 gallons per acre were applied, it produced a higher covered area. However, there was a difference when applied 10 gallons with and without adjuvant. By applying adjuvant, the trial proved more efficient in reaching the plants. Conversely, when 5 gallons were applied, the surfactant did not contribute to either the top leaves or bottom part. Therefore, our results are promising and contribute to the enhancement of technology in agricultural production. The insights allow from farms to research centers to improve the spraying drone application, guaranteeing a more sustainable environment.
Speakers
LS

Lucas Sales

Research Assistant, University of Georgia
Agronomy Engineer graduated from the Federal University of Paraíba. With experience in the management and cultivation of Ornamental Plants, through a year of experience working in Greenhouses in the state of New Hampshire, USA. Experienced in the management and cultivation of vegetables... Read More →
Co-authors
LO

Luan Oliveira

University of Georgia
NA
MB

Marcelo Barbosa

University of Georgia
RD

Regimar dos Santos

University of Georgia
Bachelor's degree in agronomic engineering from the Federal University of Mato Grosso do Sul, Brazil at 2021. Master's degree in plant production with an emphasis on computational intelligence in genetic improvement at 2022, with a doctorate in progress at the state university of... Read More →
Tuesday September 24, 2024 5:50pm - 6:00pm HST
South Pacific 2

6:00pm HST

Welcome Reception
Tuesday September 24, 2024 6:00pm - 8:00pm HST
Welcome to Honolulu!

Admission to the conference Welcome Reception is included in the conference registration fee for the registrant only.  If you are interested in bringing a guest (even a child) to this reception, you will need to purchase an appropriate Welcome Reception Guest Ticket (Adult or Child) in order for that individual to be allowed access to the reception.
Tuesday September 24, 2024 6:00pm - 8:00pm HST
 
Wednesday, September 25
 

7:00am HST

Speaker Ready Room - Wednesday
Wednesday September 25, 2024 7:00am - 6:00pm HST
Wednesday September 25, 2024 7:00am - 6:00pm HST
Sea Pearl 1-2

7:30am HST

Extension Division Breakfast and Education Materials Awards Celebration
Wednesday September 25, 2024 7:30am - 9:30am HST
Speaker: Dr. Carol Miles, Washington State University
 
Extension Outreach in a Digital World
 
Presentation description: As Extension specialists we carry out applied research and develop new research-based information and deliver it to our clientele in easy-to-understand publications. Today we must deliver our information on-line and though social media, and we track numbers of hits and downloads. How have Extension publication trends changed over the past 20-30 years, including print/online, sales/revenue, promotion/advertising, and what do we see as the future for extension publications. Forming partnerships with extension communication specialists can enable us to focus on information development, where most extension specialists do best, while achieving impacts through information access, which is how we are evaluated.
Moderator Speakers
CM

Carol Miles

Washington State University
Wednesday September 25, 2024 7:30am - 9:30am HST
Hibiscus 1

7:30am HST

Registration Open - Wednesday
Wednesday September 25, 2024 7:30am - 6:00pm HST
Wednesday September 25, 2024 7:30am - 6:00pm HST
Coral Lounge

7:59am HST

Floriculture 1 (FLOR 1)
Wednesday September 25, 2024 7:59am - 8:14am HST
Phosphate Solubilizing Bacteria: Leveraging The Soilless Substrate For Improved Phosphorus Nutrition In Controlled Environment Agriculture. - Michelle Jones
Phosphate Solubilizing Bacteria Isolated From Greenhouse Ornamentals Solubilize Phosphate In Vitro And Ameliorate P Deficiency Symptoms In Marigold ‘Durango Yellow’ Fertilized With Calcium Phosphate. - Juan Quijia Pillajo
Activated Aluminum Amended Substrates Reduce Phosphorus Leaching in Floriculture Production - Damon Abdi
Iron-coated Sand as a Sustainable Substrate Amendment for Nutrient Management of Containerized Floriculture Crops - Savannah Mead
Phosphorous Restriction Suppresses Growth of Containerized Coneflower - Garrett Owen
Investigating Synergistic Effects of Biostimulants and Biochar on Water Use Efficiency for Containerized Celosia (Argentea cristata) and Gomphrena (Gomphrena globose) Production - Lilin Chen
Effects of Reduced Water Usage During Production on Economic Value, Growth, And Quality of Flowering Indoor Plants - Kaitlin Hopkins
Moderator
DA

Damon Abdi

Louisiana State University Agricultural Center
Wednesday September 25, 2024 7:59am - 8:14am HST
Nautilus 1

7:59am HST

Plasticulture (PLAST)
Wednesday September 25, 2024 7:59am - 9:15am HST
Cover Crop Windbreaks for Slowing Biodegradable Mulch Deterioration and Improving Bell Pepper Productivity. - Caleb Wehrbein
Influence of Plastic Mulch Color on Yield and Quality of Day-neutral Strawberries - Tricia Jenkins
Exploring sustainable mulch solutions: a comparative study in strawberry production systems in northwestern Washington - Nayab Gull
Shade level effects on fruit yield of habanero chili (Capsicum chinense Jacq.) - Juan Carlos Diaz Perez
Quantum Dot Concentration in Photoconversion Covers Affects Growth Rates of Four Microgreens Species - Jeffrey Bates

Moderator
JC

Juan Carlos Diaz Perez

University of Georgia
Wednesday September 25, 2024 7:59am - 9:15am HST
Lehua Suite

7:59am HST

Produce Quality, Safety, and Health Properties (QUAL)
Wednesday September 25, 2024 7:59am - 9:30am HST
The Effect of Fruit Tree Virus and Viroid Infections on Tree Growth and Fruit Quality - Sang Yun Cho
Bacteriophage as an Alternative Method to Control Salmonella enterica in Water-Recirculated Systems for Lettuce Production - Camila Rodrigues
Transfer of Escherichia coli from Plastic Mulch to Tomato and Pepper Fruit by Ground Contact in a Field Environment - Autumn Burnett
Assessing the Impact of Biological Soil Amendments of Animal Origin on Bell Pepper Microbial Safety, Soil Properties, and Quality - Daniel Leiva
Inhibiting Foodborne Pathogens and Biofilms on Fresh Produce by Nano-emulsions Developed from Lactobacillus-Derived Exopolysaccharide and Eugenol - Sangeeta Balyan
Evaluating Nutritional Quality and Consumer Acceptability of Lettuce (Lactuca sativa L.) Grown with a Movable High Tunnel - Cary Rivard
Moderator
SY

Sang Yun Cho

agricultural researcher, National Institute of Horticultural and Herbal Science
Wednesday September 25, 2024 7:59am - 9:30am HST
Kahili

7:59am HST

Citrus Crops 2/History of Horticultural Science (CITR 2/HIST)
Wednesday September 25, 2024 7:59am - 9:45am HST
Precision Nutrition Management: Finding Optimal Methods for Leaf Nutrient Analysis in HLB-affected Citrus Trees - Meryam Manzoor
Cover Crop Effects on HLB-affected Citrus Tree Growth and Soil Characteristics: Results From a 3-year Field Trial - Lorenzo Rossi
More Frequent Irrigation Increases Yield in HLB-Affected Sweet Orange - Tripti Vashisth
Impact of Different Organic Matter Contents on ‘US-942’ Citrus Rootstock Physiology, Nutrient Uptake, and Root Morphology - Lukas Hallman
Soil Amendment Strategies to Rehabilitate Freeze Damaged Citrus Trees for Sustainable Crop Management - Shad Nelson
Physiological and Metabolomic Changes in Young Citrus Trees Under Elevated CO₂ and High Temperatures: A longitudinal study in Mandarins (C. reticulata.) - Taylor Hornburg
Reports and research on incorporating cover crops in Florida citriculture, 1896 – 2024 - Lorenzo Rossi
Moderator
avatar for Lorenzo Rossi

Lorenzo Rossi

Assistant Professor, University of Florida
Dr. Rossi’s research program focuses on improving root health and growth on cultivated crops, leading to the development of environmentally sound and effective management methods. He is a horticulturist with specific expertise related to plant stress physiology, root dynamics and... Read More →
Wednesday September 25, 2024 7:59am - 9:45am HST
South Pacific 1

7:59am HST

Genetics and Germplasm 1 (GG 1)
Wednesday September 25, 2024 7:59am - 9:45am HST
Assembling a Reference Panel of DNA Profiles for U.S. Heirloom Apple Cultivars - Cameron Peace
Rediscovering Lost Heirloom Apple Cultivars with DNA Fingerprinting - Dongyun Lee
Air or Soil Temperature: Understanding the Cues for Dormancy Transition in Peach - Ksenija Gasic
Selection and Evaluation of Citrus Resistobiome for HLB Resistance/Tolerance - Yongping Duan
Population Genetics and Genome-wide Association Studies Provide Insights into the Genetic Basis of Persea Fruit Quality Traits - Gul Ali
Genome Assembly of Persia Americana cv. Simmonds Provides Insights on Genetic Relationships Among Avocado Hybrids Exhibiting Tolerance To Laurel Wilt - Vincent Njung'e Michael
Utilizing Haploid Pollen Grains and Diploid Leaf Tissue Genomic Sequence Data to Phase the ‘Wonderful’ Pomegranate Genome - Giuseppe Lana

Moderator
CP

Cameron Peace

Washington State University
Wednesday September 25, 2024 7:59am - 9:45am HST
Coral 1

7:59am HST

Plant Growth Regulation 1 (PGR 1)
Wednesday September 25, 2024 7:59am - 9:45am HST
The Assessment of Plant Growth Regulators on Sweetpotato Slip Propagation - Kerington Bass
Effects of a Cytokinin-Containing Biostimulant Applied at Different Phenological Timings on Almond (Prunus dulcis) Yield - Orlando Tapia
Preharvest Abscisic Acid (S-ABA) Spray Application Promotes Fruit Ripening, Color Development and Regulates Quality in Early Maturing ‘Yoho’ Persimmon - Mahmood Ul Hasan
The Application of a Cytokinin B-Mo-based Product Influences the Source-to-Sink Dynamics and Non-Structural Carbohydrate - Mayra Toro Herrera
PGR applications to reduce HLB-associated preharvest fruit drop in Sweet Orange - Tripti Vashisth
Ethephon Effect on Blooming of Three Southern Highbush Cultivars - Lilian Carcamo
Development of a Tissue Culture Approach for Doubling the Ploidy Level of Southern Highbush Blueberry Varieties - Emily Walter
Moderator
avatar for Kerington Bass

Kerington Bass

Graduate Student, Mississippi State University
Originally from Louisiana Nontraditional ag background Interested in horticulture of specialty crops or ornamentals Highly interested in Controlled Environment Agriculture Looking for job opportunities Looking for opportunities to learn a second language 
Wednesday September 25, 2024 7:59am - 9:45am HST
South Pacific 3

7:59am HST

Technology Applications in Horticulture 1 (TECH 1)
Wednesday September 25, 2024 7:59am - 9:45am HST
Advanced 3D Imaging for High Throughput Phenotyping of Horticultural Crops - Yu Jiang
Integrating UAV Imagery and AI to Forecast Vidalia Onion Yield and Quality - Marcelo Barbosa
Deep Learning Application for Field Phenotyping of Shoot Structure in Grapevine - Soichiro Nishiyama
Investigation of Using Hyperspectral Vegetation Indices to Assess Brassica Downy Mildew - Bo Liu
Effect of Innovative Laser Labeling Technology on Fresh Produce Quality and Safety - Manreet Bhullar
Cover Crop Decision Support Tools: Exploring the new suite of online cover crop tools - Esleyther Henriquez Inoa
CFD-based aerodynamic analysis under high wind velocity environment for multiple greenhouses - Anthony Kintu
Moderator
SD

Shunping Ding

Associate Professor, California Polytechnic State University
Wednesday September 25, 2024 7:59am - 9:45am HST
South Pacific 2

7:59am HST

Growth Chambers and Controlled Environments 2 (CE 2)
Wednesday September 25, 2024 7:59am - 10:00am HST
Will Increasing the Potassium to Nitrogen Ratio Benefit Hydroponic Strawberry Production? - Jonathan Ries
Impact of Diurnal Chilling on Vegetative and Floral Development of Strawberry (Fragaria x annanassa) cvs. ‘Albion’, ‘Chandler’, ‘Monterey’, ‘Sensation’ Tray Plants in a Controlled Environment - Michael Palmer
Utilizing Controlled Environment Agriculture to Enhance the Yield and Flavor of Strawberries - Nicholas Cooley
Impact Of Elevated CO2 And Two Daily Light Integrals on the Production Efficiency of Strawberry (Fragaria × ananassa ‘Monterey’) Daughter Plants - Samson Humphrey
Unraveling Strawberry Stock Plant Architecture, Morphology, and Tips’ Spatial Distribution under Three Photoperiods to Facilitate Future Propagation System Design: A Comparative Study on Monterey as a Long-day Cultivar - Moein Moosavi
Stratified Wood Substrates for Optimizing Growth of Greenhouse-Grown Strawberries and Blueberries - Brandan Shur
Effect of Light Intensity on Strawberry Runner Tips Propagated Indoors - Lian Duron
Characterizing the Growth, Morphology, Productivity, and Fruit Quality of Twenty-five Strawberry Cultivars in Vertical Farm Environment - Yiyun Lin
Moderator
YL

Yiyun Lin

The Ohio State University
Wednesday September 25, 2024 7:59am - 10:00am HST
Coral 2

7:59am HST

Vegetable Crops Management 2 (VCM 2)
Wednesday September 25, 2024 7:59am - 10:00am HST
Optimizing Tomato Crop Production: Fertility Management in Soilless Media - Bryce Waugh
Improving the Growth and Yield of Tomato through new Integrated Pest Management Strategies - Rosemary Gutierrez Coarite
Assessment of Novel, Interspecific Hybrid Tomato Rootstocks for Production under Environmental Stress - Joshua Harvey
Evaluation of Biostimulant on Nutrient Use Efficiency in Tomato - Weining Wang
Alternative Carbon Sources Effects on the Soil-plant Nutrient Dynamics During and Post ASD in a High Tunnel Tomato Crop System - Francesco Di Gioia
Advancing Pepper Production Beyond Seasonal Limits: Findings from a High Tunnel System Integrated with Biostimulant Applications - Asmita Nagila
Optimizing Nitrogen Fertilizer Rate and Planting Density of Vidalia Onion Yield and Bulb Size Distributions - Elvis Pulici
Assessing the Efficacy of Plant Biostimulants on Onion Growth and Production in Greenhouse Trials and Field Conditions - Prakriti Nepal
Moderator
FD

Francesco Di Gioia

Pennsylvania State University
Wednesday September 25, 2024 7:59am - 10:00am HST
South Pacific 4

8:00am HST

CE 2 - Will Increasing the Potassium to Nitrogen Ratio Benefit Hydroponic Strawberry Production?
Wednesday September 25, 2024 8:00am - 8:15am HST
Strawberries (Fragaria × ananassa) are increasingly being grown in hydroponic systems, where effective nutrient management is critical for optimizing crop production and yield. Among essential mineral nutrients, potassium is a key nutrient that affect fruit quality in many fruiting crops. This study investigated how potassium to nitrogen (K:N) ratios regulate strawberry growth and development in a deep-water culture hydroponic system. We hypothesized that increasing the K:N ratios would enhance vegetative growth, fruit yield, and fruit quality. Bare-root plants of strawberry ‘Monterey’ and ‘San Andreas’ were grown indoor under a 23 °C air temperature and an 18-h photoperiod with an extended photosynthetic photon flux density of 350 µmol∙m–2∙s–1. The N level was kept constant at 77 ppm, while the study tested K:N ratios ranging from 1.5:1 to 4:5:1. Three weeks after nutrient treatments, strawberry plants showed similar crown number, crown diameter, leaf number, leaf area, and shoot dry mass regardless of K:N ratios in both cultivars. Increasing K:N from 1.5:1 to 4.5:1 linearly increased the root dry mass of Monterey’ but not in ‘San Andreas’. During the fruit production, K:N ratios did not affect the total number of fruits or total fresh mass of fruits. However, there was a linear decrease in the diameter, length, and fresh mass of individual fruits with increasing K:N ratio from 1.5:1 to 4.5:1 in both 'Monterey' and 'San Andreas'. Additionally, increasing K:N ratio from 1.5:1 to 4.5:1 slightly increased total soluble solids in ‘San Andreas’, but led to a greater increase in titratable acidity compared to the increase in total soluble solids in both ‘Monterey’ and ‘San Andreas’. These results suggest that increasing K:N ratios from 1.5:1 to 4.5:1 has little beneficial effect on overall plant growth, fruit yield and fruit quality for hydroponic strawberry production in deep-water culture systems.
Speakers
JR

Jonathan Ries

Arizona State University
Co-authors
YP

Yujin Park

Arizona State University
Wednesday September 25, 2024 8:00am - 8:15am HST
Coral 2

8:00am HST

CITR 2/HIST - Precision Nutrition Management: Finding Optimal Methods for Leaf Nutrient Analysis in HLB-affected Citrus Trees
Wednesday September 25, 2024 8:00am - 8:15am HST
Effective fertilizer management and accurate nutritional analysis are critical for healthy tree growth and maximum yield. Citrus trees perform best in the optimum range of each nutrient, and a deficiency or excess can result in poor tree growth and yield. Accurate fertilizer management decisions for citrus trees begin with proper leaf sampling. To accurately assess tree nutrition status, the appropriate time and procedure for collecting leaves for nutrient analysis must be followed. Historically, nutrient management for healthy citrus trees involved annual leaf sampling from July to August, with subsequent year fertilization plans based on single nutrient analysis. Currently, nearly all commercial Florida citrus orchards are affected by Huanglongbing (HLB), a systemic bacterial disease that affects all citrus varieties and rootstocks, causing extensive tree health decline. Studies suggest that a good nutrition program can improve the tree health and production of HLB-affected trees. However, the key is to supply the nutrients that are deficient or low. This widespread prevalence of HLB needs new approaches for managing fertilizer programs by regular leaf sampling to identify tree nutrient status and requirements. Thus, this study focuses to improve and revise the leaf nutrient sampling guideline for HLB-affected trees by determining the optimal time for leaf sampling and adjusting fertilization for increased production and tree health. Key objectives include assessing the frequency of leaf sampling required per year to capture the tree's nutritional status effectively and adjust fertilizer accordingly to establish the correlation of leaf nutrient concentration with the yield, fruit drop, and canopy density. For this study, spring and summer emerging flushes were tagged on HLB-affected ‘Hamlin’ and ‘Valencia’ mild and severe sweet orange trees in a central Florida orchard over two years. The leaves from tagged branches were collected every 3 months for leaf nutrient analysis and the results of both spring and summer leaves were used to adjust the fertilization plan accordingly. It was found that the spring emerging flush was optimal in adjusting the fertilizer for the highest yield compared to the summer emerging flush. With the use of precision fertilization, the improvement in tree canopy density and fruit yield was more obvious in mildly HLB-symptomatic trees compared to severely symptomatic trees. Our results demonstrate the growers should be performing nutrient sampling quarterly and use this information to precisely manage fertilization and improve tree productivity.
Speakers
MM

Meryam Manzoor

University of Florida
Co-authors
JB

Jamie Burrow

University of Florida
NA
TL

Taylor Livingston

University of Florida
NA
TV

Tripti Vashisth

University of Florida
Wednesday September 25, 2024 8:00am - 8:15am HST
South Pacific 1

8:00am HST

FLOR 1 - Phosphate Solubilizing Bacteria: Leveraging The Soilless Substrate For Improved Phosphorus Nutrition In Controlled Environment Agriculture.
Wednesday September 25, 2024 8:00am - 8:15am HST
Phosphorus (P) is an essential macronutrient with low availability for plant uptake. The availability of P is reduced by the formation of insoluble complexes with calcium (Ca) and iron (Fe). Phosphorus solubilizing bacteria (PSB) can enhance P uptake by producing organic acids that acidify the rhizosphere and breakdown the insoluble P compounds. The goal of this research is to identify PSB that can increase P uptake efficiency in soilless production systems. A collection of bacteria isolated from the rhizosphere of greenhouse grown ornamentals was used to identify PSB using both in vitro and in planta evaluations. A malachite green assay optimized for 96-well plates was used to screen 1,056 bacterial isolates for the ability to solubilize phosphorus from both calcium phosphate and iron phosphate. This in vitro assay identified 14 and 24 PSB that solubilized 25% or more of the P from Ca2(PO4)3 and FePO4·2H20, respectively. There was no overlap between the PSB that solubilized Ca2(PO4)3 and those that solubilized FePO4. In planta evaluations were conducted in Marigold ‘Durango Yellow’ (Tagetes patula) and Tomato ‘Bush Beefsteak’ (Solanum lycopersicum) grown in a peat-based substrate (pH=7) and inoculated with individual PSB as a media drench (20 mL; OD595=0.1). Digital phenotyping with the TraitFinder (Phenospex) was used to quantify growth promotion (digital biomass and bloom area), and the severity of P deficiency symptoms [Green Leaf Index (GLI), normalized difference vegetation index (NDVI), Normalized Pigment Chlorophyll Ratio Index (NPCI), and Plant Senescence Reflectance Index (PSRI)]. Only seven FePO4·2H20 solubilizers (Fe-PSB) and six Ca2(PO4)3 solubilizers (Ca-PSB) performed better than the control in at least one of the evaluated parameters. A validation experiment was conducted to confirm the beneficial activity of the seven Fe-PSB (C2F9, C3A8, C11G1, C8D10, C6E7, C3G9, and C3F10) and the six Ca-PSB (C4A1, C2G6, B3A7, C11A5, C4B6, C12F4, and C6H6). The validation experiments were conducted with Marigold ‘Durango Yellow’ and Tomato ‘Early girl’ grown in a peat-based substrate (pH=7) and inoculated with individual PSB as a media drench (20 mL; OD595=0.1). Bacillus megaterium (C3F10), Pseudomonas sp. (C6E7), and two strains of Pantoea rwandensis (C3A8 and C8D10) showed a beneficial response when applied to plants fertilized with FePO4·2H20. Only, Enterobacter soli C4A1 showed a beneficial response when applied to plants fertilized with Ca2(PO4)3. The malachite-green assay and digital phenotyping are suitable tools for high-throughput identification of PSB that can be used to improve phosphorus nutrition in soilless culture systems.
Speakers
MJ

Michelle Jones

The Ohio State University
Co-authors
JQ

Juan Quijia Pillajo

The Ohio State University
LC

Laura Chapin

The Ohio State University
NA
SN

Sachin Naik

The Ohio State University
NA
Wednesday September 25, 2024 8:00am - 8:15am HST
Nautilus 1

8:00am HST

GG 1 - Assembling a Reference Panel of DNA Profiles for U.S. Heirloom Apple Cultivars
Wednesday September 25, 2024 8:00am - 8:15am HST
Heirloom apple cultivars represent an important specialty crop for producers and a genetic resource for the dessert apple industry. These cultivars are plagued with misidentifications, which hinders utilization and long-term preservation. Phenotypic identification, used for centuries, is unable to distinguish among the thousands of existing U.S. heirlooms. DNA profiling provides an objective basis for cultivar identification. Washington State University’s “MyFruitTree” (myfruittree.org), built upon the RosBREED project and with international collaborations, has accumulated a DNA profile dataset of thousands of apple individuals focused on the U.S. genepool. Users submit leaf samples for trees of interest, and MyFruitTree’s cost-recovery research opportunity determines the cultivar identity (or reveals their uniqueness and pedigree position). However, a common and valid question is, “How do you know that is the correct identity?” The core panel of robustly identified cultivars was based on public breeding germplasm, modern cultivars, and their ancestors, which were DNA profiled in the RosBREED project last decade. Since then, examined trees from collections in the U.S. and abroad have greatly expanded the number of DNA profiles with cultivar labels. But those labels are not always correct, especially when a tree is derived from only a single source. Therefore, a system was derived for assigning confidence to the cultivar labels associated with DNA profiles. Cultivar name evidence is assembled in the categories of provenance, phenotype, and genotype for both the DNA-profiled tree and the historically named cultivar, and congruence is examined. This system is applied at two levels: streamlined and comprehensive. The streamlined approach for the current DNA profile dataset efficiently determined whether each individual belongs confidently in the “Reference Panel” or is relegated to “Accessory Profiles” pending further evidence. A Reference Panel was assembled of hundreds of U.S. heirlooms (and more than a thousand close relatives from other regions). The comprehensive approach involves attention from a transdisciplinary tribunal of experts who carefully weigh evidence that an apple individual – often a proposed new discovery of an otherwise lost heirloom – is indeed a historically named cultivar. As MyFruitTree accumulates more DNA profiles submitted by cultivar collection managers and apple enthusiasts nationwide, the cultivar name assignment system is being applied to unidentified trees with strong provenance evidence of cultivar status. Establishing accurate cultivar identities of valued trees via DNA profiling is providing the critical foundation for a coordinated national effort to sustain preservation and utilization of apple crop diversity.
Speakers
CP

Cameron Peace

Washington State University
Co-authors
DL

Dongyun Lee

Washington State University
Wednesday September 25, 2024 8:00am - 8:15am HST
Coral 1

8:00am HST

PGR 1 - The Assessment of Plant Growth Regulators on Sweetpotato Slip Propagation
Wednesday September 25, 2024 8:00am - 8:15am HST
Producing sweetpotatoes involve several phases presenting unique challenges, most notably during transplanting. Sweetpotato slips, used for asexual reproduction, have non-uniform characteristics, making transplanting difficult. Additionally, the transition from a greenhouse to a field condition poses environmental risks and challenges, resulting in low transplant survival rates. A high slip mortality rate creates economic and logistical problems for producers. Plant growth regulators (PGRs) have been found to induce lignification or thickening of cell walls, which can alleviate environmental stresses in other crops; however, their impact remains unexplored in sweetpotato slips. Therefore, a study at Mississippi State University was conducted with the primary goal to enhance sweetpotato slip quality and improve transplant establishment rates. The study involves two greenhouse trials to identify the most effective PGR types and concentrations, and two histology trials to illustrate the effects of PGRs on sweetpotato slip lignin and cell wall. The greenhouse trials utilize a randomized complete block design to assess four different PGR types and thirteen concentrations on three replications of sweetpotato slips with 38 subsamples per treatment per replication. Data on plant height, stem diameter, number of nodes, SPAD, leaf area, and dry weight and fresh weight of the slips and roots were collected to determine the effects of PGRs on the plants. The histology trials included the same PGR treatments and concentrations to the slips. The slips were then collected, cross-sectioned, stained, and evaluated and measured under a microscope. The study proved that PGRs do have an effect on sweetpotato slips, by altering plant height, dry weight, and fresh weight, while not impacting the number of nodes. Thickening of the cell wall was also observed in slips treated with certain PGRs and it is hypothesized that this thickening of cell walls can contribute to reduced slip mortality when transplanting greenhouse produced slips to the field.
Speakers
avatar for Kerington Bass

Kerington Bass

Graduate Student, Mississippi State University
Originally from Louisiana Nontraditional ag background Interested in horticulture of specialty crops or ornamentals Highly interested in Controlled Environment Agriculture Looking for job opportunities Looking for opportunities to learn a second language 
Co-authors
BG

Bi Guihong

Mississippi State University
LH

Lorin Harvey

Mississippi State University
NA
RH

Richard Harkess

Mississippi State University
NA
TB

Taylor Blaise

Mississippi State University
NA
Wednesday September 25, 2024 8:00am - 8:15am HST
South Pacific 3

8:00am HST

PLAST - Cover Crop Windbreaks for Slowing Biodegradable Mulch Deterioration and Improving Bell Pepper Productivity.
Wednesday September 25, 2024 8:00am - 8:15am HST
Polyethylene mulch films have become a dominant production practice to increase the yield potential of high value crops, but they are a significant source of environmental contamination. Alternatively, biodegradable mulches are a potentially sustainable alternative , but are less popular among growers as they vary in durability and performance in the field environment. Cover crops when sufficiently tall may be able to improve biodegradable mulch durability by reducing wind intensity within a mulched bed. To quantify the utility of a cover crop windbreak, we tested the effect of a fall-planted, 6ft wide strip of cereal rye planted parallel to the southern side of mulched bell pepper beds. Whole plot treatments included presence or absence of rye and split plot treatments included a comparison of polyethylene mulch, biodegradable mulch, and a bare ground control. Day windspeeds were reduced in peppers protected by a south-facing cereal rye strip by 60% relative to unprotected peppers. Large hole occurrences in biodegradable mulch were reduced by 50% and small holes by 15% in peppers protected by a cereal rye strip relative to unprotected peppers. Peppers grown behind the cover of cereal rye had a 42% reduction in leaning plants compared to peppers without cereal rye. Stomatal conductance was increased by 27% in peppers protected by cereal rye relative to unprotected peppers as a result of reduced windspeeds, though there were no differences in fruit yields. Results suggest cover crops can extend the useful life of biodegradable mulch films, which may help address a common barrier to adoption. Ongoing research aims to better understand the effects of the cover crop on crop health, yield, and quality.
Speakers
CW

Caleb Wehrbein

University of Nebraska - Lincoln
Co-authors
SW

Samuel Wortman

University of Nebraska - Lincoln
Wednesday September 25, 2024 8:00am - 8:15am HST
Lehua Suite

8:00am HST

QUAL - The Effect of Fruit Tree Virus and Viroid Infections on Tree Growth and Fruit Quality
Wednesday September 25, 2024 8:00am - 8:15am HST
This study aimed to investigate the impact of virus and viroid infections on tree growth and fruit quality attributes in apple, pear, peach, and grape. Trials were conducted in 2019 at the National Institute of Horticultural and Herbal Science in Korea, utilizing virus-infected, viroid-infected, combined virus/viroid-infected, and uninfected trees in an experimental fruit-tree orchard. Additionally, the experimental orchard served as an exhibition package for farmers and agricultural workers. Annual measurements of tree growth were compared between virus-free and virus/viroid-infected trees. Fruit quality attributes, including yield, weight, firmness, titratable acidity, and anthocyanin content, were assessed during 2021-2023. The results revealed significant differences between virus-free trees and those infected with virus, viroid, or both. Viral and viroid infections led to reduced tree height, trunk area, fruit yield, fruit weight, and anthocyanin content, while increasing fruit firmness and titratable acidity, respectively. These findings are expected to contribute to fruit tree virus and viroid disease control and fruit cultivation management. Furthermore, we anticipate that this research will enhance the understanding of agricultural stakeholders through scientific and comprehensive evidence on the damages caused by fruit tree viruses and viroid infections, thereby stimulating the adoption of virus-free stocks and promoting their widespread distribution.
Speakers
SY

Sang Yun Cho

agricultural researcher, National Institute of Horticultural and Herbal Science
Co-authors
BY

Byeonghyeon Yun

National Institute of Horticultural and Herbal Science
NA
HR

Hyun Ran Kim

National Institute of Horticultural and Herbal Science
NA
KH

Kang Hee Cho

Rural Development Administration
NA
SH

Se Hee Kim

National Institute of Horticultural and Herbal Science
NA
SO

Sewon Oh

National Institute of Horticultural and Herbal Science
NA
Wednesday September 25, 2024 8:00am - 8:15am HST
Kahili

8:00am HST

TECH 1 - Advanced 3D Imaging for High Throughput Phenotyping of Horticultural Crops
Wednesday September 25, 2024 8:00am - 8:15am HST
Understanding plant growth and development is crucial for insights into plant structure and function, and recent advancements in AI-driven 3D imaging technologies have revolutionized the acquisition and analysis of high-fidelity plant models. These technologies enable accurate and rapid measurement of phenotypic traits, aiding breeders in developing new varieties and helping horticulturists optimize production management. The overarching goal of this study was to establish an AI-based 3D imaging and analysis pipeline specifically designed for detailed examination of horticultural crops at the organ level within controlled environments. We developed a robotic platform equipped with a rotating base and a high-resolution camera mounted on a robotic arm, allowing comprehensive imaging from any angle around the plant. Utilizing this robot, we generated 3D models of 30 hemp plants from two growth-rate categories in controlled environments, on a weekly basis. An AI model was developed to segment these 3D models into stems, branches, and leaves. Morphological traits were extracted from each category of the segmented organs, including stem length (i.e., plant height), stem diameter, branch length, branch diameter, leaf number, leaf area, and leaf aspect ratio. These measurements contributed to a classification model capable of distinguishing between fast and regular growth rates. Experimental results showed that the 3D imaging-derived measurements were highly correlated with human-derived measurements. In addition, the extracted traits were used as quantitative descriptors to classify hemp cultivars with different growth rates in CEA. Therefore, the developed pipeline can be used as an effective and efficient tool for breeding programs and CEA production management in the future.
Speakers
YJ

Yu Jiang

Cornell University
Co-authors
JM

Jonathan Moon

Cornell University
NA
LS

Larry Smart

Cornell University
NA
NM

Neil Mattson

Cornell University
RD

Ruiming Du

Cornell University
NA
Wednesday September 25, 2024 8:00am - 8:15am HST
South Pacific 2

8:00am HST

VCM 2 - Optimizing Tomato Crop Production: Fertility Management in Soilless Media
Wednesday September 25, 2024 8:00am - 8:15am HST
Tomatoes are one of the most important greenhouse produced crops and the number of producers using greenhouse to grow them has risen in recent years. Sustainable development and effective resource management are becoming more and more important to the agricultural industries as well. Applying fertilizer precisely is becoming more and more important in different agricultural systems. Different physical and chemical characteristics of soilless growing substrate result in varying capacities for retaining nutrients. As a result, precise fertilizer rates are essential. This study investigated 14 fertilizer blends with varying proportions of nitrogen (0-400ppm), phosphorus (0-100ppm), and potassium (0-425). Six-cell seedling starter trays were filled with Berger BM6, and 'Big Beef' tomato seeds were planted. After four weeks, the seedlings were transplanted into five-gallon aeration fabric grow bags. Plants were hand-watered once a week with each treatment fertilizer rate to maintain a 10% leaching fraction. End measurements included the number of leaves, dry shoot weight, fresh root weight, dried root weight, and SPAD readings. The study revealed that a higher rate of nitrogen increased fresh shoot weight and lower rates of phosphorous increased number of non-harvestable fruits, increasing the need for further investigation to determine optimal fertilizer rates for various specialty crops grown in soilless greenhouse environments. Such endeavors are crucial for maximizing agricultural productivity while minimizing resource wastage and environmental impact.
Speakers
BW

Bryce Waugh

Grad Student, Oklahoma State University
Co-authors
BD

Bruce Dunn

Oklahoma State University
Wednesday September 25, 2024 8:00am - 8:15am HST
South Pacific 4

8:00am HST

ASHS Conference Central - Wednesday Hours
Wednesday September 25, 2024 8:00am - 5:00pm HST
Wednesday September 25, 2024 8:00am - 5:00pm HST
Coral 4/5

8:00am HST

Exhibit Hall Hours - Wednesday
Wednesday September 25, 2024 8:00am - 5:00pm HST
Wednesday September 25, 2024 8:00am - 5:00pm HST
Coral 4/5

8:15am HST

CE 2- Impact of Diurnal Chilling on Vegetative and Floral Development of Strawberry (Fragaria x annanassa) cvs. ‘Albion’, ‘Chandler’, ‘Monterey’, ‘Sensation’ Tray Plants in a Controlled Environment
Wednesday September 25, 2024 8:15am - 8:30am HST
In US open field nurseries, strawberry transplants for fruit production accumulate diurnal chilling hours (hours between -2 and 7°C) in the field prior to harvest and receive supplemental chilling as bare root plants in a cooler before being transplanted into a fruit production system. In nurseries in Northwestern Europe, tray plants are placed outside after rooting to accumulate diurnal chill hours and are moved into the cooler with leaves and substrate for supplemental chilling before being transplanted. The optimal amount of chilling varies among cultivars but is thought to contribute to a proper balance of vegetative vigor and floral development leading to best fruiting after transplanting into the production system. Climate change, labor cost and related issues cause problems in both nurseries and production. Therefore more and more growers and start-up companies venture into controlled environment production systems. Due to high cost, these systems require transplants that are optimally conditioned for early flowering. We evaluated the impact of diurnal chilling on vegetative and floral development of 250 cc strawberry tray plants in a controlled environment. 28 day old ‘Albion’, ‘Chandler’, ‘Monterey’, and ‘Sensation’ rooted daughter plants were moved into growth chambers where they received 0 (15°C 24 hours), 100 (4°C, 16°C), 250 (4°C, 19°C), or 450 (4°C, 24°C) chill hours over a six week period. Within each treatment, the same amount of chill hours were applied each day for the six week period. Among treatments, the non-chill temperature increased as the number of chill hours increased to ensure the same daily average temperature of 15°C. Chambers were fixed at 50% RH, 450 ppm CO2, 130-40 µmol m-2 s-1 for all treatments and a 12 hour photoperiod for ‘Chandler’ and ‘Sensation’ and a 16 hour photoperiod for ‘Albion’ and ‘Monterey’. After the treatment, all plants were dissected under the microscope to determine the number and development of floral meristems (flower mapping). Our results show that the plants in the 100 and 250 hour treatments produced more floral meristems and branch crowns than the 0 and 450 hour treatments across all cultivars. Additionally, in ‘Albion’ and ‘Monterey’, the plants of the 100 and 250 hour treatments had greater fresh mass and higher crown diameter than the plants in the 0 and 450 hour treatments. Finally, all cultivars except ‘Sensation’ had more flowers on plants in the 100 and 250 hour treatments than those of the 0 and 450 hour treatments.
Speakers
MP

Michael Palmer

North Carolina State University
Co-authors
MH

Mark Hoffmann

North Carolina State University
NA
Wednesday September 25, 2024 8:15am - 8:30am HST
Coral 2

8:15am HST

CITR 2/HIST - Cover Crop Effects on HLB-affected Citrus Tree Growth and Soil Characteristics: Results From a 3-year Field Trial
Wednesday September 25, 2024 8:15am - 8:30am HST
Citrus greening, or Huanglongbing (HLB), poses a severe threat to Florida’s citrus industry, impacting tree health and yield. Due to the lack of a known cure, growers employ various strategies to manage its effects, including increased nutrient application. However, in regions like the Indian River District (IRD), characterized by poor soil fertility and organic matter content, nutrient retention is challenging. Consequently, there is growing interest in using cover crops to enhance soil fertility. Despite this, there is limited published data on their effectiveness in the IRD. To address this gap, a collaborative study was initiated in Ft. Pierce, Florida, involving a commercial grower and the University of Florida. A three-year field trial, employing a randomized complete block design with four blocks, included ‘Star Ruby’ grapefruit trees grafted on ‘US-942’ rootstock, ‘Bearss’ lemon trees on ‘Sour Orange’ rootstock, and ‘OLL’ sweet orange trees on 'US-942' rootstock. Two treatments were applied: conventional (without cover crops) and experimental (with cover crops). Cover crops were planted bi-annually (winter and summer), grown, and terminated at each season’s end. Soil nutrient content, organic matter, microbiome diversity, moisture, and temperature, as well tree and root growth parameters were measured seasonally. After three years of cover cropping, significant differences in soil nutrient content, organic matter, and microbiome diversity were observed between the conventional and experimental treatments, suggesting potential impacts of cover crops on soil characteristics. However, there were no noticeable effects on tree growth or physiology. This study is ongoing and aims to provide a comprehensive understanding of the long-term effects of cover cropping on soil parameters in HLB-affected citrus groves, informing sustainable management practices in citrus cultivation.
Speakers
avatar for Lorenzo Rossi

Lorenzo Rossi

Assistant Professor, University of Florida
Dr. Rossi’s research program focuses on improving root health and growth on cultivated crops, leading to the development of environmentally sound and effective management methods. He is a horticulturist with specific expertise related to plant stress physiology, root dynamics and... Read More →
Co-authors
AW

Alan Wright

University of Florida
NA
JF

John-Paul Fox

University of Florida
LH

Lukas Hallman

University of Florida
Wednesday September 25, 2024 8:15am - 8:30am HST
South Pacific 1

8:15am HST

FLOR 1 - Phosphate Solubilizing Bacteria Isolated From Greenhouse Ornamentals Solubilize Phosphate In Vitro And Ameliorate P Deficiency Symptoms In Marigold ‘Durango Yellow’ Fertilized With Calcium Phosphate.
Wednesday September 25, 2024 8:15am - 8:30am HST
Phosphorus (P) is an essential macronutrient absorbed by plants as orthophosphate (PO4). P availability depends on the pH of the substrate. At high pH, P forms insoluble compounds like Ca3(PO4)2 which is unavailable for plant uptake. Phosphate solubilizing bacteria (PSB) are plant-associated microorganisms that can break down Ca3(PO4)2 by secreting organic acids. PSB have been primarily evaluated as inoculum for crops grown in soil to improve P availability. However, less is known about the application of PSB in ornamentals grown in soilless substrates. Our goal was to identify PSB from a collection of bacteria isolated from the rhizosphere of greenhouse ornamentals. First, the collection was screened in vitro for the bacterial capacity to reduce pH of the media using the bromophenol-blue color assay. Thirty-five isolates were identified to reduce media pH, and their P solubilization capacity was quantified using ion chromatography. Fourteen isolates with the highest P solubilization were selected for whole-genome sequencing, but only two bacterial isolates (C2B11 and C8D10) were advanced to the in-planta evaluation using Marigold (Tagetes patula) 'Durango Yellow' grown in a peat-based substrate (pH = 7). Plants were irrigated with 100 mg·L-1 N from a 15N-0P-15K fertilizer, and P was supplemented weekly as Ca3(PO4)2 via substrate drench applications. Lalrise Vita (Lallemand Plant Care) and Bacillus velezensis (the active ingredient in Lalrise Vita) were included as positive controls. Plant phenotyping was conducted using the TraitFinder automatic system (Phenospex). TraitFinder assessment parameters included digital biomass, bloom area, Green Leaf Index (GLI), Normalized Pigment Chlorophyll Ratio Index (NPCI), and Plant Senescence Reflectance Index (PSRI). Lalrise Vita performed better than the control in all the parameters evaluated. B. velezensis increased bloom area and showed higher GLI and lower NPCI than the control. Pantoea sp. C2B11 significantly increased digital biomass, bloom area, and GLI. Pantoea sp. C8D10 only showed an increase in GLI values. Both C2B11 and C8D10 possess various genes involved in gluconic acid production. We identified two PSB that solubilize P in vitro, promote growth and bloom area, and improve canopy health (high GLI or low NPCI) in marigold plants fertilized with Ca3(PO4)2. Our next step is to validate the growth-promoting capacity of the identified PSB in other ornamentals. PSB can contribute to improving phosphorus nutrition and fertilizer use efficiency in greenhouse ornamental production.
Speakers
JQ

Juan Quijia Pillajo

The Ohio State University
Co-authors
MJ

Michelle Jones

The Ohio State University
NN

Nathan Nordstedt

FMC Corporation
NA
Wednesday September 25, 2024 8:15am - 8:30am HST
Nautilus 1

8:15am HST

GG 1 - Rediscovering Lost Heirloom Apple Cultivars with DNA Fingerprinting
Wednesday September 25, 2024 8:15am - 8:30am HST
U.S. heirloom apple cultivars are an underutilized and threatened resource, that DNA fingerprinting can help save and remobilize. These heirlooms are old cultivars that were named, clonally propagated, and distributed more than a century ago. Many heirloom cultivars have great historical value, some are still grown commercially, and others could be reintroduced to enhance rural prosperity and diversify options for consumers. While some heirloom cultivars are ancestors of modern cultivars, many others could be valuable for future breeding. However, most heirlooms have been long neglected, and thousands once documented are already extinct. Before more heirlooms disappear forever, mystery trees need to be distinguished from known cultivars, identified, and adequately preserved. Leaf samples for more than 2000 apple trees in collections, national heritage sites, old orchards, and backyards across the U.S. were crowdsourced from about 150 “MyFruitTree” submitters and DNA fingerprinted using KASP genotyping with 48 SNPs. The cultivar identity or uniqueness of each tree was determined by comparing obtained DNA profiles to a previously developed dataset of several thousand apple cultivars and individuals. Trees with replicates were prioritized into five categories according to several criteria for likelihood of representing heirloom cultivars. After removing duplicate samples, poor genotypic data, and non-apple samples, about 60% (1202) of samples were identified as cultivars and most were heirlooms. Of the unidentified samples, 85% (665) were unique, and 15% (118) of the samples represented replicated trees. We found five “Priority 1” trees (filled cultivar pedigree gaps or from three U.S. regions) and four “Priority 2” trees (detected in two regions). Hundreds more trees likely representing unknown heirlooms were also identified in single regions. Collaborators across the country, including historians and citizen scientists, can now closely examine the highest priority trees to uncover their historic cultivar names, while ensuring they are propagated so that they are preserved and valued once again. As more old apple trees are DNA fingerprinted, it is expected that current “unique” DNA profiles will be replicated in the same or other regions. Replicated trees must represent propagated, valued, and likely named cultivars, increasing the opportunities to rediscover lost heirlooms.
Speakers
DL

Dongyun Lee

Washington State University
Co-authors
AD

Amy Dunbar-Wallis

University of Colorado
NA
CP

Cameron Peace

Washington State University
JB

John Bunker

Maine Heritage Orchard
NA
RM

Rebecca McGee

USDA-ARS Pullman
NA
TL

Todd Little-Siebold

College of the Atlantic
NA
Wednesday September 25, 2024 8:15am - 8:30am HST
Coral 1

8:15am HST

PGR 1 - Effects of a Cytokinin-Containing Biostimulant Applied at Different Phenological Timings on Almond (Prunus dulcis) Yield
Wednesday September 25, 2024 8:15am - 8:30am HST
Almond (Prunus dulcis) is one of the most important crops in California. This commodity represented an economic impact of over 3.5 billion dollars for the state in 2022. During that year, 1,630,000 million planted acres were reported. In 2023, this number dropped by 74,000 acres, continuing the trend of decline due to numerous challenges that the industry has been facing. These include volatile prices, high input costs, reduced water allocations, climate unpredictability, and high temperatures during key phenological timings. The almond crop is highly sensitive to environmental factors, and photosynthetic rates can significantly decrease when temperatures reach 94F, heat levels are easily reached during the hot summer months in California’s production areas. To this matter, significant contributions are needed to support the industry. There are over 700 peer-reviewed scientific publications that evidence the benefits of using biologicals, which include plant biostimulants (PBS), in agriculture. It has been shown that season-long exogenous applications of cytokinin-containing PBS can support higher marketable yields. It is important to understand the physiological timings in which these applications have the most impact, in terms of maximizing the yield and quality potential. In 2023, a randomized complete-block design (RCBD) study was conducted on 5th leaf Var. Nonpareil in California’s Central Valley. The objective was to evaluate the yield and quality effects of an application of X-CyteTM, a 0.04% cytokinin-containing biostimulant registered for use on almonds in California, at different standalone phenological timings. These included early bloom, full bloom, petal fall, may spray, and hull-split. The trial consisted of six four-tree replications per treatment. Yield and quality data were subjected to a one-way ANOVA using IBM® SPSS® Statistics, and means were separated using Tukey’s HSD. The standard grower practice (SGP) produced 1801.5 marketable pounds of kernel meat per acre. X-Cyte™ treatment yields of 1845.16, 2140.16, 2215.66, 2137.67, and 2318.33, were observed for early bloom, full bloom, petal fall, may spray, and hull-split timings, respectively. Statistically significant differences were observed (p-value: 0.003). The hull-split and petal fall timing applications represented the higher yield increases (516.8 and 414.2 lbs/A, respectively) overall, compared to the SGP. It has been documented that taking place at these timings are key phenological stages deemed as major contributors to the components of yield: fruit set and nut fill. Significant differences in kernel size were not observed (p-value: 0.549). These findings further support and help fine-tune the use of biologicals and PBS in agricultural production systems.
Speakers
OT

Orlando Tapia

California State University Fresno / Corteva Agriscience
Co-authors
DG

Dave Goorahoo

California State University, Fresno
RM

Ryan Miller

Corteva Agriscience
NA
Wednesday September 25, 2024 8:15am - 8:30am HST
South Pacific 3

8:15am HST

PLAST - Influence of Plastic Mulch Color on Yield and Quality of Day-neutral Strawberries
Wednesday September 25, 2024 8:15am - 8:30am HST
High tunnel production of day-neutral strawberries is a promising production system in the central U.S. The use of different colored plastic mulches in a high tunnel production system can vary the microclimate around plants and alter yield and fruit quality. This study was conducted to identify the most appropriate color plastic mulch in a high tunnel production system as it relates to yield and fruit quality. The experiment was conducted at the Kansas State University, Olathe Horticulture Research and Extension Center in 2020 and 2021 using a split-plot, randomized complete block design. We evaluated six plastic mulches (black, white, striped silver, silver, red, and green) and two day-neutral cultivars, ‘Albion’ and ‘Portola’. Soil temperature and UV light reflected from the mulch were measured to monitor microclimate modifications. Fruit quality was assessed by overall visual quality, color, soluble solids content, titratable acidity, sugar/acid ratio, total phenolics, and anthocyanin content of strawberries. 'Portola’ produced greater yields than ‘Albion’, but ‘Albion’ had better fruit quality. The plastic mulches altered the reflected UV light and soil temperatures. During the mid and late season, the silver mulch had higher fruit yields than the red and green mulches, likely due to its ability to limit solar warming during warm production months. The mulches had inconsistent impacts on fruit quality. Overall, the silver mulch maintained the best microclimate for day-neutral strawberry production in high tunnels.
Speakers
TJ

Tricia Jenkins

Kansas State University
Co-authors
AM

Amrita Mukherjee

University of California, Davis
Amrita Mukherjee, Urban Agriculture/Small Farm Advisor at the University of California Agriculture and Natural Resources in Southern California, focuses on research and education in organic farming, urban agriculture, and sustainable practices for small-scale growers in both field... Read More →
CR

Cary Rivard

Kansas State University
EP

Eleni Pliakoni

Kansas State University
Wednesday September 25, 2024 8:15am - 8:30am HST
Lehua Suite

8:15am HST

QUAL - Bacteriophage as an Alternative Method to Control Salmonella enterica in Water-Recirculated Systems for Lettuce Production
Wednesday September 25, 2024 8:15am - 8:30am HST
In recent years, controlled environment agriculture (CEA) has gained popularity as a sustainable and efficient method of cultivation, offering solutions to challenges posed by traditional farming practices and meeting the growing demand for high-quality produce. However, advancements in CEA have raised concerns about food safety, requiring new approaches to minimize the risk of produce contamination. This research explores the effectiveness of a bacteriophage cocktail as a biocontrol agent against Salmonella contamination in lettuce grown in water-recirculating systems. Salmonella Newport and Salmonella Typhimurium (103 CFU/mL) were inoculated into aquaponic and hydroponic nutrient solutions into a water-recirculating system to mimic sporadic contamination, followed by treatment with a bacteriophage cocktail (S7, S10, and S13) at different multiplicities of infection (MOI 0.01 and MOI 1). The results demonstrated a significant reduction in Salmonella Newport and Salmonella Typhimurium populations at both MOI 0.01 and MOI 1 in aquaponic and hydroponic nutrient solutions, with levels reaching below the limit of detection (LOD) after 3 to 4 days of bacteriophage cocktail inoculation. From the plant parts, there was a significant reduction in the microbial population of Salmonella serovars in media plugs and roots from the hydroponic nutrient solution, reaching levels below the LOD in both phage cocktail treatments after a 2-day inoculation period. Contrarily, significant reductions were not observed in Salmonella serovar levels in plant roots and media plugs from the aquaponic nutrient solution treatment. These findings highlight the potential of utilizing bacteriophages to improve food safety in indoor-grown lettuce by controlling Salmonella populations while also indicating the necessity for further research to understand the microbial dynamics within each type of system.
Speakers
CR

Camila Rodrigues

Auburn University
Co-authors
CB

Caroline Blanchard

Auburn University
DW

Daniel Wells

Auburn University
NA
VM

Vania Mickos

Auburn University
NA
Wednesday September 25, 2024 8:15am - 8:30am HST
Kahili

8:15am HST

TECH 1 - Integrating UAV Imagery and AI to Forecast Vidalia Onion Yield and Quality
Wednesday September 25, 2024 8:15am - 8:30am HST
Forecasting yield and quality of Vidalia onions allows the stakeholders to make decisions on the best time and place to harvest. While yield defines an important quantitative parameter, conversely, sweetness emerges as timely factor of quality. Traditionally, measuring these parameters requires a field team and routine laboratory for the assessments, making it a subjective, time-consuming, labor-intensive, costly, and not-scalable approach. However, image technology and artificial intelligence (AI)-based methods could improve decision-making strategies. In this study, we collected unmanned aerial vehicle (UAV) multispectral images of two Vidalia onions fields from crop establishment until the harvest date, totaling six sets of images for each field. Each flight was performed with approximately 15 days apart. At the harvest date, 50 samples were collected in each field to determine yield, while 10 samples were used for sweetness. To ensure the robustness of the dataset, both fields were combined into a single dataset. Consequently, we used machine learning (ML) algorithms to perform predictive models, namely multiple linear regression (MLR), random forest (RF), and support vector machine (SVM). The dataset was split into 70% and 30% for training and testing, respectively, and the predictions were performed using the test dataset. Regarding the assessment of the models, we used the metrics namely coefficient of determination (R2), mean absolute error (MAE), and root mean squared error (RMSE). The models with higher R2 and lower MAE and RMSE were the bests. Notably, the considerable correlation between yield and spectral data made the MLR model perform well as more complex models such as RF. Conversely, when there was a weak correlation between the sweetness and spectral data, RF model could perform much better. In short, both models (MLR, RF, and SVM) could perform well into a predictive model, which highlights the strength of spectral data for representing Vidalia onions either quantitative or qualitative parameters. Therefore, our study not only represents an innovation in the field of specialty crop production, but also brings ready-to-use solutions to improve the production process and introduce Vidalia onions into the concept of field technology.
Speakers
MB

Marcelo Barbosa

University of Georgia
Co-authors
LO

Luan Oliveira

University of Georgia
NA
LS

Lucas Sales

University of Georgia
Agronomy Engineer graduated from the Federal University of Paraíba. With experience in the management and cultivation of Ornamental Plants, through a year of experience working in Greenhouses in the state of New Hampshire, USA. Experienced in the management and cultivation of vegetables... Read More →
RD

Regimar dos Santos

University of Georgia
Bachelor's degree in agronomic engineering from the Federal University of Mato Grosso do Sul, Brazil at 2021. Master's degree in plant production with an emphasis on computational intelligence in genetic improvement at 2022, with a doctorate in progress at the state university of... Read More →
Wednesday September 25, 2024 8:15am - 8:30am HST
South Pacific 2

8:15am HST

VCM 2 - Improving the Growth and Yield of Tomato through new Integrated Pest Management Strategies
Wednesday September 25, 2024 8:15am - 8:30am HST
Tomato (Solanum lycopersicum L.) is the number one vegetable crop in Hawaii in terms of popularity and market value. Of the total tomatoes consumed in Hawaii only 23% is produced locally. Local production has decreased substantially over the past few years due to crop losses caused primarily by the Tomato Yellow Leaf Curl Virus (TYLCV), which is vectored by whiteflies Bemisia tabaci and Bemisia argentifolii. Crop losses by TYLCV in tomato crops on Maui range between 60 to 100%. Efforts to keep plants from becoming infected, manage the rate of infection, timing, or severity of the infection are needed to protect crop health. Therefore, a new integrated pest management approach was conducted integrating the use of reflective ground cover, companion plants, insecticides, and tomato varieties resistant to TYLCV. The highest total weight (4.4 lb/pl per harvest time) was observed in the variety PS01522935 in the treatment combining reflective ground cover and companion plants and the highest marketable weight was observed in the same treatment in the varieties PS01522935 and Mesquite (3.5 lb/pl per harvest time), and the highest TYLCV infection was observed in the conventional treatment in the varieties Paisano followed by Healani, Celebrity Plus and Kewalo, and the varieties with no TYLCV infection were PS01522935, SVTD8601 and Mesquite. The use of reflective ground cover and companion plants may reduce TYLCV infections in tomato crops by reducing whitefly populations.
Speakers
RG

Rosemary Gutierrez Coarite

University of Hawaii at Manoa
Wednesday September 25, 2024 8:15am - 8:30am HST
South Pacific 4

8:30am HST

CE 2 - Utilizing Controlled Environment Agriculture to Enhance the Yield and Flavor of Strawberries
Wednesday September 25, 2024 8:30am - 8:45am HST
Presentation: Oral ASHS 2024 Keywords: CEA, greenhouse, Fragaria ×ananassa, temperature Utilizing Controlled Environment Agriculture to Enhance the Yield and Flavor of Strawberries Nicholas Cooley, Joshua Vanderweide, and Roberto Lopez In the U.S., strawberries (Fragaria ×ananassa) are the most popular berry fruit with a value of $2.8B. In 2022, strawberries experienced 12% growth in annual sales, with the majority of field production occurring in California and Florida. To meet consumer demand for flavorful, fresh, local, and year-round fresh strawberries, the industry is expanding controlled environment (CE) production of day-neutral (everbearing) cultivars in greenhouses and indoor farms. Within CEs, growers can potentially meet these demands through the manipulation of environmental parameters such as temperature, light, vapor pressure deficit, and carbon dioxide concentration. Despite the recent growth, CE growers are reporting low profitability. This imbalance of production and profitability stems from high energy costs, supra-optimal greenhouse temperatures during parts of the year, and low yield from the industry standard cultivar ‘Albion’. For producers to be considered profitable, they must reach an approximate annual yield of 15 kg∙m–2, which equates to a weekly yield of around 0.3 kg∙m–2. The objectives of our research are to 1) quantify the yield of other day-neutral cultivars in greenhouses; 2) determine how day and night temperature influence yield and fruit quality parameters; and 3) develop a model to predict the cardinal temperatures of each cultivar. Three cultivars, ‘Albion’, ‘Cabrillo’, and ‘Monterey’ were grown at day/ night temperatures (12 h/ 12 h) of 15/7, 18/10, 21/13, 24/16 or 27/19 °C, under a 16-h photoperiod, and a target DLI of 15 mol·m–2·d–1. Fruits were harvested three times weekly and at harvest, berry weight, diameter, color, shape, distortion, brix content, and flavor-related volatile organic concentrations were recorded. After 12 weeks of harvest, the highest average weekly yield was 0.17, 0.19, and 0.24 kg∙m–2 for ‘Albion’, ‘Cabrillo’ ‘Monterey’ at 18/10, 24/16, and 24/16 C, respectively. While the highest combined overall yield for all three cultivars was at 24/16 °C, the highest average berry weight differed. At day and night temperatures of 18/10, 18/10, and 15/7 °C, ‘Albion’, ‘Cabrillo’, and ‘Monterey had the highest average berry weights, respectively. Our results collectively indicate there are higher yielding day-neutral cultivars than the industry standard ‘Albion’.
Speakers
NC

Nicholas Cooley

Michigan State University
Wednesday September 25, 2024 8:30am - 8:45am HST
Coral 2

8:30am HST

CITR 2/HIST - More Frequent Irrigation Increases Yield in HLB-Affected Sweet Orange
Wednesday September 25, 2024 8:30am - 8:45am HST
Huanglongbing (HLB) causes a steady decline in tree health. Part of this decline includes root dieback which limits their capacity to take up water. For this reason, affected trees tend to be more susceptible to drought stress. This raises a significant concern during the dry season (Oct-May) when trees are largely dependent on supplemental irrigation for water. Unfortunately, most growers continue using irrigation schedules that were optimized for healthy trees. We hypothesized that irrigating more frequently, but in smaller doses would provide more opportunities for uptake and improve water relations in HLB-affected trees. The control treatment received the standard practice of irrigating every other day for 2 hours (12 gal/hr). The experimental treatment received water every day, 3 times a day, for 20 minutes (12 gal/hr). The two treatments received the same amount of water over the course of a week, but the experimental treatment received water more often. Treatments were initiated prior to flowering in January 2022 and were continued for two years. Tree water status improved in the experimental trees as reflected in higher mid-day leaf water potentials than in the control. This suggests the experimental regime was better able to maintain tree water status than the conventional method. In the second year, flowering was more synchronized in the experimental treatment. The control treatment saw two peaks in bud production with the latter one being consistent with a drought stress-induced flowering event. The experimental trees also saw an increase in fruit set in both years. Trees receiving the experimental and control treatments dropped a similar proportion of their crop load during June Drop and preharvest fruit drop in year 1 and 2. Finally, the experimental treatment resulted in significantly higher yields on average than the control in both year 1 and year 2 (72% and 200%, respectively). Altogether, more frequent irrigation improved tree productivity.
Speakers
TV

Tripti Vashisth

University of Florida
Co-authors
MS

Mary Sutton

University of Florida
NA
Wednesday September 25, 2024 8:30am - 8:45am HST
South Pacific 1

8:30am HST

FLOR 1 - Activated Aluminum Amended Substrates Reduce Phosphorus Leaching in Floriculture Production
Wednesday September 25, 2024 8:30am - 8:45am HST
The use of water-soluble fertilizers in floricultural production provides readily available nutrients to sustain short-term crop production; however, nutrients such as phosphorus are poorly retained in typical peat substrates. Activated aluminum is an amendment that has demonstrated success in binding phosphorus within substrates, reducing the amount of phosphorus that is leached from the container. This research investigated the production of Tagetes in peat-based substrates amended with or without activated aluminum and provided four different phosphorus fertilizer regimens. The fertilizer regimens encompassed a nitrogen, phosphorus, and potassium liquid blend applied weekly; however, phosphorus was only included for 0, 2, 4, or 6 weeks in total over the duration of the study. Growth of Tagetes was effectively similar, and leachate analysis provided insights that can be applied towards more efficient production methods. In this research, utilizing activated aluminum resulted in less phosphorus loss in container leachate than unamended substrates. The potential to decrease applied phosphorus during floricultural production can similarly be achieved when using substrates amended with activated aluminum. This presentation will decipher the dynamics of the movement of phosphorus and other anions of interest that may be relevant to sustainable floriculture production.
Speakers
DA

Damon Abdi

Louisiana State University Agricultural Center
Co-authors
JF

Jeb Fields

LSU AgCenter Hammond Research Station
JB

Jeffrey Beasley

University of North Carolina - Pembroke
NA
Wednesday September 25, 2024 8:30am - 8:45am HST
Nautilus 1

8:30am HST

GG 1 - Air or Soil Temperature: Understanding the Cues for Dormancy Transition in Peach
Wednesday September 25, 2024 8:30am - 8:45am HST
Peach trees require quantitative exposure to winter chilling (chilling requirement, CR) for spring bloom. The chill accumulation time points are determined using weather data of air temperatures between 32 and 45 ºF, using various calculation methods such as the simple chill hour (CH) method or more sophisticated methods like Utah and Chill portions (CP) that account for negations of chilling due to warm weather during the dormancy. All these methods rely on air temperature and do not consider the soil temperature during the dormancy and its effect on the tree’s perception and account for chill accumulation. Peach flowers and developing fruit are highly sensitive to freezing temperatures and are killed following even a limited exposure. In the past decade, mild winters and early spring frosts have significantly reduced or eliminated the annual peach production in the southeast U.S. Low-chill winters have become increasingly common in the southeastern peach-producing regions, and when followed by warm springs, result in early bud break and early flowering, increasing the risk of crop loss to frost. Due to a replant issue caused by Armillaria root rot, almost all acreage under the new peach orchards in the southeast, including South Carolina, are planted on berms adopting root collar excavation as a method to extend the life of orchards on infested soil. We observed significant differences between the air temperature and temperature of undisrupted soil and soil within berms at various depths (3, 6, 12 and 18 in) during dormancy. The effect of observed temperature differences on ‘Cresthaven’ tree chill accumulation calculation and transition between endo- and eco-dormancy stages was investigated by collecting vegetative bud and root tissue from all four depths at six chill hour time points (400, 500, 600, 700, 800 and 900). Preliminary data show significant gene expression differences between bud and root tissue and different gene expression profiles related to the chill accumulation in each tissue. Detailed analyses of the gene expression profiles between the tissues at the different chill accumulation stages and their effect on chilling and heat accumulation, bloom time, and the transition between the dormancy stages in peaches will be discussed.
Speakers
avatar for Ksenija Gasic

Ksenija Gasic

Clemson University
Co-authors
CS

Christopher Saski

Clemson University
NA
JL

John Lawton

Clemson University
NA
SP

Stephen Parris

Clemson University
ZL

Zhigang Li

Clemson University
NA
Wednesday September 25, 2024 8:30am - 8:45am HST
Coral 1

8:30am HST

PGR 1 - Preharvest Abscisic Acid (S-ABA) Spray Application Promotes Fruit Ripening, Color Development and Regulates Quality in E
Wednesday September 25, 2024 8:30am - 8:45am HST
Persimmon is an important fruit crop gown all over the world due to its unique fruit taste and nutritional quality. The skin color is one of the key attributes in persimmon fruit to determine the harvest maturity. Poor color development in early maturing cultivars causes losses to the growers. The present study was aimed at evaluating the effects of preharvest S-ABA spray application on advancing color development and improving fruit quality at harvest. ‘Yoho’ persimmon trees grown in Western Australia were sprayed with S-ABA (0, 25, 50, 75 mg L-1) two weeks before anticipated harvest. The preharvest spray application of S-ABA showed significant increase in color indicators such as color index, a*, b*, and chroma of persimmon fruit harvested after one and two weeks of spray application. S-ABA (25 and 50 mg L-1) spray application showed significantly higher soluble solids content (SSC), and slightly reduced firmness in harvested fruit. Additionally, the 50 mg L-1 S-ABA spray application markedly increased carotenoids content in fruit harvested after one week, while fruit harvested after two weeks exhibited higher carotenoids in 25 mg L-1 and 50 mg L-1 S-ABA treatments. Moreover, the total phenolics, flavonoids and antioxidants were enhanced by S-ABA treatments as compared to control. In conclusion, the preharvest spray application of S-ABA (50 mgL-1) triggers fruit ripening sharply even after one week, while 25 mg L-1 S-ABA treatment showed significant improvement in color after two weeks of application. A single spray application of S-ABA could be employed for advancing harvest maturity, color development, and promoting overall persimmon fruit ripening quality.
Speakers
MU

Mahmood Ul Hasan

Edith Cowan University
I am a PhD student in Horticulture at Edith Cowan University, Australia. My areas of interest include assessment of preharvest factors affecting quality, understanding physiological and biochemical processes and factors affecting shelf life and quality (consumer and nutritive aspects... Read More →
Co-authors
AW

Andrew Woodward

Edith Cowan University
NA
AW

Andrew Woodward

Edith Cowan University
NA
EA

Eben Afrifa- Yamoah

Edith Cowan University
NA
EA

Eben Afrifa- Yamoah

Edith Cowan University
NA
HM

Hafiz Muhammad Shoaib Shah

Edith Cowan University
NA
ZS

Zora Singh

Edith Cowan University
Wednesday September 25, 2024 8:30am - 8:45am HST
South Pacific 3

8:30am HST

PLAST - Exploring sustainable mulch solutions: a comparative study in strawberry production systems in northwestern Washington
Wednesday September 25, 2024 8:30am - 8:45am HST
Agricultural plastic mulch made from non-biodegradable polyethylene (i.e., “PE mulch”) provides many horticultural benefits. However, PE mulch requires annual removal and disposal, which generates large volumes of plastic waste that is rarely recycled and can become a pollutant. Incomplete removal of PE mulch also can leave behind plastic fragments that threaten soil and ecosystem health. To address these challenges, soil-biodegradable mulches (BDMs) have emerged as a potentially more eco-friendly alternative. BDMs are designed to provide the same advantages for specialty crop production as PE mulch and naturally biodegrade when incorporated into the soil. In addition, non-biodegradable reflective mulch has emerged as a promising mulch technology that may reduce key insect pests. The objective of this research was to evaluate the impacts of different mulch technologies, including soil-biodegradable and reflective mulches, on horticultural and pest dynamics in day-neutral strawberry (Fragaria×ananassa cv. Albion) in northwest Washington. Seven mulch treatments were established in a randomized complete block design with four replications in 2023. Treatments included green and black BDM made with ecovio and Mater-Bi feedstocks, non-biodegradable metalized mulch, and controls of black PE mulch and unmulched plots. Yield from all mulch treatments did not differ significantly from black PE control except for the green BDM made with ecovio feedstock. The green BDM made with ecovio resulted in significantly lower (32%) yield, similar to unmulched control. Lower yield may be attributed to the rapid deterioration of the green BDM treatments, which lacks carbon black and deteriorated more rapidly compared to other mulch treatments. However, black BDM made from MaterBi feedstock and metalized mulch were 37% and 11% less deteriorated than PE control respectively. Additionally, all mulch treatments suppressed weeds better than the unmulched control and were not different from black PE mulch. Aphid and thrips populations were highest in unmulched plots, whereas metalized mulch had fewer thrips (on sticky cards) and fewer aphids (on leaves) than all other treatments. Overall, the study highlighted that black BDM performs similarly to PE mulch with regards to potential weed suppression and maintenance of yield, whereas the rapid deterioration of green BDM could effect the soil microclimate and subsequent plant growth. Despite rapid mulch deterioration, the study did not observe compromised weed management. Metalized mulch may contribute to reducing pest populations but impacts on pollination and biological control remains unknown. Additional research on soil health effects is required given the fate of BDMs is in-soil incorporation.
Speakers
NG

Nayab Gull

Washington State University
Wednesday September 25, 2024 8:30am - 8:45am HST
Lehua Suite

8:30am HST

QUAL - Transfer of Escherichia coli from Plastic Mulch to Tomato and Pepper Fruit by Ground Contact in a Field Environment
Wednesday September 25, 2024 8:30am - 8:45am HST
In the southeast US, tomatoes (Solanum lycopersicum) and bell pepper (Capsicum annuum) are typically staked and trellised and grown using plastic mulch for weed control. The Produce Safety Rule that is part of the Food Safety Modernization Act requires that fruit from tomato and pepper be declared non-harvestable if they fall to the ground or contact the ground through drooping while attached to the plant before harvest. The objective of this study was to quantify percent transfer from plastic mulch inoculated with Escherichia coli with green fluorescent protein (GFP) to pepper and tomato fruit making ground contact in spring and fall growing seasons. E. coli GFP was spot inoculated on plastic mulch in the field using ten - 10 µL drops (100 uL total) at approximately 7 log CFU/mL and allowed to dry for at least 1 h before fruit contact. In the spring season, white and black colored plastic mulch were compared and in the fall season, reused (second crop) plastic mulch and new white plastic mulch were compared. Fruit contacted the ground by drooping (remained attached to the plant) with a contact time of 1 h or 24 h as well as contact through dropping fruit at heights of 30 cm, 60 cm, and 120 cm (n=9 per treatment). After inoculum was allowed to dry on the plastic mulch, the E. coli population was reduced an average of 2.8 and 4.8 log CFU/mL, in the spring and fall seasons, respectively. In both seasons all dropped peppers had significantly different percent transfer than dropped tomatoes, while drooping fruit were not significantly different between the two commodities. In the fall, dropped fruit on new plastic had significantly greater bacterial transfer than fruit which was dropped on reused plastic for both tomato and pepper. No significant differences were obtained between drooping duration treatments or between the different height of dropping in either season. There was relatively low transfer overall from both drooping and dropping of fruit on inoculated plastic mulch, regardless of crop or season. Further, in this inoculated study, results suggest that there was a significant reduction in E. coli populations in a field setting after a short period of exposure to the natural environment.
Speakers
AB

Autumn Burnett

University of Georgia
Co-authors
BR

Blanca Ruiz Llacsuanga

University of Georgia
NA
FC

Faith Critzer

University of Georgia
NA
HG

Halle Greenbaum

University of Georgia
NA
RR

Rawane Raad

University of Georgia
NA
TC

Timothy Coolong

University of Georgia
Wednesday September 25, 2024 8:30am - 8:45am HST
Kahili

8:30am HST

TECH 1 - Deep Learning Application for Field Phenotyping of Shoot Structure in Grapevine
Wednesday September 25, 2024 8:30am - 8:45am HST
In the cultivation of fruit trees and vines, plant architecture is a critical determinant of productivity. While there are considerable diversities in plant architecture, which can be modified through pruning in fruit production, a method for high-throughput measurement and recording of architecture has not yet been established, posing a limitation to research and development in this area. Here we evaluated Transformer-based architecture for detecting above-ground shoot network of grapevine in an outdoor vineyard condition. The problem here was defined as the detection of nodes (buds or branching points) and their physical relationships (internodes or edges) within plant images. We also developed an evaluation metric inspired by the inherent structure of plant shoots to efficiently smooth detected structures to more closely resemble realistic systems in plants. The proposed framework has been successfully applied to the detection task in outdoor condition with complex background. Through the application of this method, we have demonstrated that our proposed framework is capable of extracting topological parameters of dormant shoot architecture of grapevine that effectively models the shoot biomass in a large-scale vineyard.
Speakers
SN

Soichiro Nishiyama

Kyoto University
Co-authors
DG

Dario Guevara

Department of Viticulture
NA
GG

Guillermo Garcia Zamora

Department of Viticulture
NA
ME

Mason Earles

Department of Viticulture
NA
Wednesday September 25, 2024 8:30am - 8:45am HST
South Pacific 2

8:30am HST

VCM 2 - Assessment of Novel, Interspecific Hybrid Tomato Rootstocks for Production under Environmental Stress
Wednesday September 25, 2024 8:30am - 8:45am HST
A growing global population and worsening global environmental change necessitate the development of improved crop varieties and cultivation techniques. In tomatoes, the world’s most popular vegetable crop, grafting has emerged as a cultivation technique for addressing these challenges through improving tomato crop vigor and stress resistance, especially to abiotic stresses that are becoming more widespread including heat, salinity, and drought stress. In order to expand the offerings of tomato rootstocks, we have conducted multiple trials to assess the beneficial impact of 10 novel tomato rootstocks on ‘Celebrity’ scion vigor and stress resistance. The rootstocks, developed by colleagues at the King Abdullah University of Science and Technology (KAUST) consist of interspecific Solanum spp. hybrids including two tetraploid hybrids. We conducted three trials to assess the impact of grafting with the novel rootstocks, including a greenhouse pot trial to quantify growth and vigor and two controlled environment trials to assess stress resistance. In each trial, ‘Celebrity ’ scions were grafted with either the novel rootstocks, ‘Maxifort’, ‘Multifort’, or left ungrafted. In the greenhouse trial, measurements of stem diameter, shoot height, shoot canopy projection area, and fresh and dry weights at harvest were used to determine overall vigor. We identified five and eight of the novel rootstock grafting combinations that outperformed the ungrafted and ‘Maxifort’-grafted plants, respectively. Additionally, measurements of SPAD and observations of foliage coloration provided initial evidence of differential nutritive requirements between the novel rootstocks. In our controlled environment trials, chlorophyll fluorescence, SPAD, and porometer data demonstrated differential susceptibility to salinity, heat, and drought stress between the rootstocks. This presentation will highlight key differences in morphological and physiological traits that assisted us in selecting a narrow set of rootstocks for a forthcoming evaluation in a passive high tunnel to demonstrate the utility of these new rootstocks.
Speakers Co-authors
NR

Nathaly Rodriguez Ortiz

King Abdullah University of Science and Technology
NA
Wednesday September 25, 2024 8:30am - 8:45am HST
South Pacific 4

8:45am HST

CE 2 - Impact Of Elevated CO2 And Two Daily Light Integrals on the Production Efficiency of Strawberry (Fragaria × ananassa ‘Monterey’) Daughter Plants
Wednesday September 25, 2024 8:45am - 9:00am HST
Abstract: Strawberry nurseries face many challenges, and are considering controlled environment propagation as an alternative to conventional open-field propagation. Limiting factors to economic feasibility include stock plant yield (number of daughters produced per stock plant). From published research we know that increasing CO2 concentration and light intensity increases strawberry photosynthetic rate, however there has been no research on the effects of these treatments on the total stock plant yield of daughters. Our hypothesis is that higher light intensity and CO2 concentrations will improve plant growth and lead to greater total daughter plant production. The objective of this experiment is to increase stock plant yield by increasing CO2 concentration (500, 850, and 1200 μmol mol-1) and light intensity (DLI 14.4 and 28.8 mol m-2 d-1). Strawberry (Fragaria × ananassa Duch., ‘Monterey’) stock plants were transplanted into three controlled environment growth chambers, under combinations of CO2 and DLI treatments in a split plot design under 26°C, 65% relative humidity, and a 16-hour photoperiod. The stock plants were grown under treatment conditions for 70 days, and newly-formed daughters were logged every day. At the end of the experiment the stock plants and their daughter plants were harvested, and each daughter plant was evaluated based on its size (number of leaves, leaf area, and fresh/dry mass). Increasing CO2 concentration linearly increased stock plant yield, leading to 23.96% more daughter plants per mother plant from the 500 to the 1200 μmol mol-1 treatment. Plants under higher light intensity (500 μmol m-2 s-1) had 38% higher stock plant yield than those under 250 μmol m-2 s-1. These data support our hypothesis that increasing CO2 concentration and light intensity increase the total yield of daughter plants produced per stock plant. By optimizing CO2 concentration and light intensity, strawberry nurseries may be able to grow more daughter plants more efficiently in controlled environment nurseries than in the conventional open-field system.
Speakers Co-authors
RH

Ricardo Hernandez

North Carolina State University
NA
Wednesday September 25, 2024 8:45am - 9:00am HST
Coral 2

8:45am HST

CITR 2/HIST - Impact of Different Organic Matter Contents on ‘US-942’ Citrus Rootstock Physiology, Nutrient Uptake, and Root Morpholog
Wednesday September 25, 2024 8:45am - 9:00am HST
The disease citrus greening (HLB, Huanglongbing) continues to decimate Florida’s citrus industry, resulting in the lowest yields since the 1940s. With no cure or tolerant rootstock/scion combinations available, growers must manage the disease. Although increased fertilizer applications have been shown to improve tree health, the additional inputs are expensive and decrease operational profitability. As a result, interest has grown in improving soil fertility parameters such as organic matter, with the goal of reducing inputs and increasing horticultural sustainability. Despite the recognized potential of organic matter, little research has been undertaken to establish the optimal contents required to improve citrus root characteristics. The objective of this study was to answer two specific questions: what are the amounts of organic matter needed to significantly affect citrus root growth and physiology? And how does the incorporation of organic matter influence nutrient availability? To answer these questions, a six-month completely randomized greenhouse experiment was conducted to measure the impact of different soil organic matter contents on potted citrus trees. Six different treatments consisting of different organic matter contents (0% - control, 1%, 2%, 3%, 5%, and >10%) were created by mixing different amounts of locally sourced compost with sand. One-year-old ‘US-942’ (Citrus reticulata x Poncirus trifoliata) rootstock plants (n = 6 per treatment) were grown in the different mixtures for six months under controlled greenhouse conditions. During the study, soil moisture, plant height, and stem diameters were assessed every other month. At the conclusion of the study, total plant and root biomass, root nutrients, average root length, and average root diameter were measured. Results from the study indicated that higher organic matter contents (>2%) led to significantly increased plant biomass and stem diameter, and increased root growth. Significant results were also found at the soil level, where increased organic matter contents led to increased nutrient retention and increased root uptake of nutrients. Additional investigation is needed to better understand the advantages of increasing organic matter content, even by marginal percentages, utilizing grafted citrus trees of various cultivars in field trials. Such trials would provide insights into the practical implications of these findings within the industry.
Speakers
LH

Lukas Hallman

University of Florida
Co-authors
AW

Alan Wright

University of Florida
NA
JF

John-Paul Fox

University of Florida
LR

Lorenzo Rossi

University of Florida
Wednesday September 25, 2024 8:45am - 9:00am HST
South Pacific 1

8:45am HST

FLOR 1 - Iron-coated Sand as a Sustainable Substrate Amendment for Nutrient Management of Containerized Floriculture Crops
Wednesday September 25, 2024 8:45am - 9:00am HST
As natural resources dwindle, sustainable alternatives to current fertilization methods are essential for environmental and economic progress. Acid mine drainage (AMD) and phosphorus from fertilizer runoff are significant sources of water pollution in the Appalachian region of the United States. Horticultural producers are faced with rising prices of phosphate fertilizers, putting the industry in a tenuous position: reducing these costly inputs to minimize water pollution but, in turn, diminishing product quality. AMD-based iron-coated sand is a novel phosphate sorbent that can potentially ameliorate AMD and prevent further phosphate pollution. This technology can cut growers’ input costs and slow the consumption of finite phosphate resources. This study aimed to determine the viability of iron-coated sand as a substrate amendment for reducing phosphate leaching and enhancing growth, flowering, and phosphorus uptake of floriculture crops during and after production. The ideal sand-to-potting mix ratio was determined based on pansies, petunias, and chrysanthemums' growth, flowering, and leachate content. The rate of applied phosphate and P-saturation of sand were determined from growth, flowering, and leachate data of chrysanthemum during production. Finally, the effects of the coated sand were examined on petunia and chrysanthemum growth, flowering, mineral content, and leachate composition over time in production and post-production environments. Twenty percent P-saturated iron-coated sand with low to moderate rates of applied phosphorus reduces leached phosphate with no deleterious, and usually positive, effects on the performance of floriculture crops during and after production. Iron-coated sand as a substrate amendment in container production of ornamentals has tremendous potential for advancing environmental and economic sustainability in the horticultural industry.
Speakers
SM

Savannah Mead

West Virginia University
Co-authors
EP

Eugenia Pena Yewtukhiw

West Virginia University
NA
KB

Karen Buzby

West Virginia University
NA
LL

Lance Lin

West Virginia University
NA
NW

Nicole Waterland

West Virginia University
NA
Wednesday September 25, 2024 8:45am - 9:00am HST
Nautilus 1

8:45am HST

GG 1 - Selection and Evaluation of Citrus Resistobiome for HLB Resistance/Tolerance
Wednesday September 25, 2024 8:45am - 9:00am HST
Since no Huanglongbing (HLB)-resistant citrus cultivar is available in the world, selection of elite natural mutants of commercial citrus for HLB-resistance/tolerance becomes a much more appealing breeding approach, especially in HLB-epidemic regions. In this study, we have selected and evaluated more than 30 citrus mutants from commercial citrus varieties in the past eight years in Florida. After greenhouse and field trials with high HLB disease pressure, we have identified several citrus lines with improved HLB-resistance/tolerance, which can be released or used for large scale of field trials. Our analyses of these lines have revealed that citrus resistobiome plays a role in the HLB resistance/tolerance, which involves a plant virus that can enhance plant resistance and illustrated the pursuit of breeding for biocontrol and a healthy microbiome. Meanwhile, we revealed that transposons have driven the selection and diversification of sweet orange (SWO). We identified six transposon families with up to 8900-fold activity increases in modern sweet orange cultivars tracing back to a common ancestor ~500 years ago. Notably, these six families of transposons contribute significantly to the formation of major cultivar groups, with frequent independent activations or accelerations observed in the breeding history of SWO. We will discuss the molecular mechanisms underlying the improved HLB-resistance, especially how the resistobiome plays a role in the improved HLB resistance/tolerance, and how to implement this new approach by utilizing and expanding the breeding of citrus resistobiome for the control of citrus HLB.
Speakers
YD

Yongping Duan

USDA ARS
NA
Co-authors
BW

Bo Wu

Clemson University
NA
DZ

Desen Zheng

USDA ARS
NA
FL

Feng Luo

Clemson University
NA
ZD

Zhanao Deng

University of Florida
Wednesday September 25, 2024 8:45am - 9:00am HST
Coral 1

8:45am HST

PGR 1 - The Application of a Cytokinin B-Mo-based Product Influences the Source-to-Sink Dynamics and Non-Structural Carbohydrate
Wednesday September 25, 2024 8:45am - 9:00am HST
Understanding the sink-to-source relationship on leafy crops offers valuable insights into optimizing resource allocation for enhanced plant growth and quality. Variations in growth rates and carbon pools across individual leaves or groups of leaves at similar developmental stages allow us to understand the plant strategies of carbon allocation and partitioning. We hypothesized that products that enhance the carbon source-to-sink relationship during leaf development can lead to increased growth and dry matter accumulation. This project aimed to determine if the exogenous application of a cytokinin and B-Mo-based product during leaf development would impact carbon source-to-sink relationship and, hence, influence plant growth and quality. The experiment was a complete randomized design with two treatments consisting of a negative control and the application of the product twice during the growing cycle. The experimental unit consisted of a deep-water culture reservoir with three lettuce plants. Destructive sampling was conducted at five sampling points. At each sampling point (n=4 per experimental run), the phenological stage was determined, and root and shoot length and dry matter, leaf length, width, area, and non-structural carbon and chlorophyll contents were measured. This data was used to estimate growth rates. Results indicate that the cytokinin and B-Mo-based product increased the number of true unfolded leaves by 1 ± 0.4 and the overall size of the lettuce head by 9%. The treated lettuce reached a marketable size four days earlier than the control treatment. Statistically significant differences were observed in the shoot and root dry matter accumulation and foliar length and width at some sampling points. Some of the growth indices indicate an increase in leaf surface area investment and enhanced conversion efficiency of assimilates into biomass in plants treated with the product. Plants exhibiting these alterations had higher sucrose and total soluble sugar content. There was a noticeable pattern of higher concentrations of non-structural carbohydrates, proteins, and amino acids in the leaves compared with the roots across all plants and treatments. Overall, our study on using a cytokinin and B-Mo-based product to strengthen the source-to-sink relationship during the development of a leafy crop provides new insights into non-structural carbohydrate metabolism and the role of CKs, B, and Mo in generating a high-quality plant in a shorter timeframe.
Speakers
avatar for Mayra Toro Herrera

Mayra Toro Herrera

Postdoctoral Research Associate, University of Connecticut
Co-authors
RR

Rosa Raudales

University of Connecticut
Wednesday September 25, 2024 8:45am - 9:00am HST
South Pacific 3

8:45am HST

PLAST - Shade level effects on fruit yield of habanero chili (Capsicum chinense Jacq.)
Wednesday September 25, 2024 8:45am - 9:00am HST
Habanero chili fruit is shiny, orange, or red, about 5 cm long, and very pungent (200,000 to 300,000 Scoville heat units). It is popular in Mexico, Central America, and the Caribbean, although it is increasing in demand in the U.S. There is reduced information on chili production under shade nets. The objective was to determine the effects of shade level and cultivar on the fruit yield of habanero chili. The study was conducted in Tifton, Georgia, under field conditions in two seasons. Habanero plants were grown using raised beds, black plastic film mulch, and drip irrigation, following the University of Georgia extension recommendations for bell peppers. The experimental design was a randomized complete block with four replications and 10 treatments (5 shade levels x 2 cultivar combinations). Habanero chili ‘Kabal’ and ‘Kukulkan’ were grown at 0% (unshaded), 30%, 47%, 62%, and 80% shade levels. Marketable fruit number and yield decreased quadratically with shade level, although there were no statistical differences in marketable yield for plants in unshaded conditions and 30% and 47% shade levels. Mean marketable yields were 33.6 t/ha (unshaded) and 5.7 t/ha (80% shade level). Less than 2.5% of total fruit were affected by sunscald and blossom-end rot. Total and marketable fruit numbers and yields and individual fruit size were higher in ‘Kukulkan’ than in ‘Kabal.’ In conclusion, although shading increased fruit size, it did not improve marketable yield compared to unshaded conditions.
Speakers
JC

Juan Carlos Diaz Perez

University of Georgia
Co-authors
MB

Mamata Bashyal

University of Massachussets
YK

Yamin Kabir

Khulna University
NA
Wednesday September 25, 2024 8:45am - 9:00am HST
Lehua Suite

8:45am HST

QUAL - Assessing the Impact of Biological Soil Amendments of Animal Origin on Bell Pepper Microbial Safety, Soil Properties, and Quality
Wednesday September 25, 2024 8:45am - 9:00am HST
The shift towards sustainable food production has forced farmers to explore alternative practices, such as the use of Biological Soil Amendments of Animal Origin (BSAAOs). However, concerns due to food safety regulations restrict the use of BSAAOs on crops consumed raw. This study assessed the microbial safety of bell peppers, the impact of BSAAOs on soil properties, and on quality. The field experiment was established with 36 plots (88 ft2) planted with bell pepper seedlings on 12-inch centers for a total of 20 plants/plot. BSAAO treatments consisted of either raw CM, PL, or non-BSAAO (NB) application, with each treatment being either tilled or top dressed. E. coli/Total Coliforms were determined from soil samples collected during weeks 1, 3, 6, and 12 and from harvested bell peppers during weeks 13 and 14. Nalidixic acid resistant E. coli was inoculated on bell peppers for a 5-day die-off determination (40 inoculated on the upper portion and 40 on the side). Ammonium and nitrate content in soil was determined before and after the establishment of the experiment, while SOM content was determined from soil samples collected after the experiment. Higher levels of E. coli (1.1–2.6 log CFU/g) and total coliforms (4.1–4.7 log CFU/g) were reported in plots with BSAAO application as compared to NB plots (1.00–1.17 log CFU/g; 3.89–4.14 respectively), although levels decreased significantly after one week. E. coli levels on bell peppers previously inoculated declined by over 2 logs within four days, with a die-off rate of 0.57 and 0.51 log CFU/cm2/day for bell peppers inoculated on top and on the side, respectively. CM tilled plots had slightly higher E. coli levels (0.02 log CFU/ cm2). The quality of bell peppers was unaffected by BSAAOs. NB top dressed and CM tilled plots had higher soil organic matter (SOM) content (2.18 and 2.08%, respectively) while both CM and PL increased soil nitrate and ammonium content significantly by the end of the experiment. CM and PL can enrich soil with inorganic nitrogen without compromising produce quality. However, the use of untreated BSAAOs poses a risk of cross-contamination, which highlights the importance of minimizing potential contamination events. Overall, this study highlighted the potential of CM and PL as BSAAOs to enhance soil fertility while maintaining food safety. It emphasized the need for appropriate management practices to mitigate risks associated with microbial contamination, ensuring the safety and sustainability of food production systems.
Speakers
DL

Daniel Leiva

Louisiana State University
Co-authors
AA

Achyut Adhikari

Louisiana State University AgCenter
NA
JM

Juan Moreira

University of Arkansas
NA
KF

Kathryn Fontenot

LSU AgCenter
Wednesday September 25, 2024 8:45am - 9:00am HST
Kahili

8:45am HST

TECH 1 - Investigation of Using Hyperspectral Vegetation Indices to Assess Brassica Downy Mildew
Wednesday September 25, 2024 8:45am - 9:00am HST
Downy mildew, caused by Hyaloperonospora parasitica, poses a significant threat to Brassica oleracea crops, leading to substantial reductions in yield and marketability. This study seeks to assess various vegetation indices for detecting different levels of downy mildew infection in a Brassica variety, Mildis, using hyperspectral data. Through artificial inoculation with H. parasitica sporangia suspension, distinct levels of downy mildew disease were induced. Spectral measurements, ranging from 350 nm to 1050 nm, were performed on the leaves under controlled environmental conditions, and reflectance data were collected and processed. The Successive Projections Algorithm (SPA) and signal sensitivity calculations were employed to identify the most informative wavelengths, which were then used to develop Downy Mildew Indices (DMI). A total of 37 existing vegetation indices and three proposed DMIs were evaluated to assess downy mildew infection levels. The results revealed that a support vector machine achieved accuracies of 71.3%, 80.7%, and 85.3% in distinguishing healthy leaves from those with early (DM1), progressed (DM2), and severe (DM3) infections, respectively, using the proposed downy mildew index. The development of this novel downy mildew index has the potential to facilitate the creation of an automated monitoring system for downy mildew and aid in resistance profiling in Brassica breeding lines.
Speakers
BL

Bo Liu

California Polytechnic State University
NA
Co-authors
MF

Marco Fernandez

California Polytechnic State University
NA
SD

Shunping Ding

California Polytechnic State University
TL

Taryn Liu

California Polytechnic State University
NA
Wednesday September 25, 2024 8:45am - 9:00am HST
South Pacific 2

8:45am HST

VCM 2 - Evaluation of Biostimulant on Nutrient Use Efficiency in Tomato
Wednesday September 25, 2024 8:45am - 9:00am HST
To evaluate the efficacy of a commercial available biostimulant (a product containing friendly microorganisms like N2 fixing bacteria) on the improvement of nitrogen (N) and phosphorus (P) use efficiency in tomato, two independent field experiments were conducted in West Central Florida in the fall production season of year 2023. For both experiments, treatments included a factorial combination of two biostimulant rates (0 or 0.247 kg/ha) and four fertilizer rates (N or P2O5) (0, 67, 135, 202 or 269 kg/ha) that were arranged in a split-plot design. Biostimulant was applied as a solution drenched in soil following transplanting, and fertilizer treatments were applied as pre-plant application in soil and/or through drip injection during the season. Commercial tomato cultivar ‘HM1823’ was chosen as plant material. Analysis of variance (ANOVA) revealed that biostimulant did not have statistically significant influence on fruit marketable yield, fruit quality (Brix) and plant biomass, regardless of application rates of P2O5. By contrast, however, application of N had statistically (P
Speakers
WW

Weining Wang

University of Florida
Co-authors
LS

Lakesh Sharma

University of Florida
Dr. Lakesh Sharma is an assistant professor of soil fertility and sustainable agriculture at the University of Florida in Gainesville, FL. Lakesh has been farming since he was a child on his own farm. His academic school journey started in 2000. He is currently working on nutrient... Read More →
SA

Shinsuke Agehara

University of Florida
Wednesday September 25, 2024 8:45am - 9:00am HST
South Pacific 4

9:00am HST

CE 2 - Unraveling Strawberry Stock Plant Architecture, Morphology, and Tips’ Spatial Distribution under Three Photoperiods to Facilitate Future Propagation System Design: A Comparative Study on Monterey as a Long-day Cultivar
Wednesday September 25, 2024 9:00am - 9:15am HST
The US strawberry industry needs healthy, high-quality transplants every year for fruit production. Following the challenges in open-field nurseries, research is focused on controlled-environment agriculture as a potential alternative to not only increase strawberry tip yield but also to produce healthier, virus-free transplants (rooted tips). Growing stock plants indoors where the runners grow vertically downward increases the yield and quality of tips, however, there is a lack of information on the general architecture of plants especially the spatial distribution of daughter plants and also the leaf area index (LAI) distribution of the daughter plants’ canopy in the growing space. This information is vital for future system design as it determines the distance between the shelves and the potential need for intracanopy lighting. Furthermore, besides temperature, photoperiod strongly affects the trade-off between runner Vs. flower production. Yet, there is also a lack of information on how photoperiod will change the yield, quality, and architecture of stock plants in CEA, specifically on long-day cultivars. Here, we examined 12, 16, and 20 h photoperiods with the same DLI of 26 mol m-2 d-1 on ‘Monterey’ as a long-day cultivar with two replications in time. The chamber environment was maintained at a high temperature of 26 °C, ambient CO2, and 65% relative humidity. The plant density was 9 plant m-2. Following 64 days of growth, parameters related to yield, architecture, and quality were recorded. Results showed that even under relatively high temperatures, with shortening the photoperiod, a linear increase in the number of tips was observed, increasing from ~36.3 to ~44.3 (18%) with the same DLI. Regardless of the photoperiod, the highest proportion of tips (30.8%) were harvested on the runners from 40 – 80 cm distance from the mother plant, though the highest LAI (53.2%) was recorded on the tips from 0 – 40 cm, causing a sudden drop (92.8%) in the light intensity after 40 cm where most of the tips are growing. This information shows the need for intracanopy lighting under 40 cm depth from the mother plants. Around 98% of the tips were harvested from 0 – 160 cm, showing the needed space for the growth of runners (i.e., the distance between the shelves). Several morphology and photosynthetic parameters were also recorded. The information from this study will be used as a base for a follow-up experiment comparing top versus intracanopy lighting.
Speakers
MM

Moein Moosavi

NC State University
https://www.linkedin.com/in/moein-moosavi-nezhad/
Co-authors
RH

Ricardo Hernandez

NC State University
NA
Wednesday September 25, 2024 9:00am - 9:15am HST
Coral 2

9:00am HST

CITR 2/HIST - Soil Amendment Strategies to Rehabilitate Freeze Damaged Citrus Trees for Sustainable Crop Management
Wednesday September 25, 2024 9:00am - 9:15am HST
Citrus in key citrus production states in the U.S. have been heavy hit from insect borne and disease pressures. The bacterial disease Huanglongbing (HLB) has had devastating impacts on the citrus industry in Florida. Despite having this threat to the Texas industry as well, the most recent negative impact to decrease citrus acreage has been due to harsh climatic events. In February 2021, citrus groves in south Texas were hit with icy weather that exposed orchards to prolonged freezing temperatures for several hours. The impacts of this one event reduced citrus orchards in south Texas by approximately 25% (over 2,800 ha or 7,000 acres). Climate variability has increased grower awareness to the potential for more frequent extensive drought and freezing winter periods. To better evaluate how to rehabilitate freeze damaged citrus trees, a two-year field study was created aimed at improving tree root health and soil conditions. Compost amendment (CA) was broadcast applied as well as application underneath the tree canopy of grapefruit trees in combination with varying nitrogen fertilizer rate application. Three fertilizer treatments: T1 (base rate = 112 kg N ha-1), T2=1.5x and T3=2x the T1 base rate were evaluated in a randomized complete block design with (11.2 Mg CA ha-1) and without CA in Rio Red grapefruits. Results indicated that root abundance significantly increased under composted trees compared to non-composted trees. Composted trees led to higher yields within 18 months following the freeze event compared to non-composted trees. The impacts of this research may aid Texas citrus growers and other producers looking to improve in-field management strategies that may assist in preparation for post-freeze weather events and extended seasons of water scarcity.
Speakers
SN

Shad Nelson

Dean and Professor, Texas A&M University Kingsville
Dr. Shad Nelson has serves as the Dean of the Dick & Mary Lewis Kleberg College of Agriculture & Natural Resource since 2016.  Prior to this he served as a Professor teaching Horticulture Science courses and research in alternative irrigation strategies for South Texas Citrus industry... Read More →
Co-authors
Wednesday September 25, 2024 9:00am - 9:15am HST
South Pacific 1

9:00am HST

FLOR 1 - Phosphorous Restriction Suppresses Growth of Containerized Coneflower
Wednesday September 25, 2024 9:00am - 9:15am HST
Containerized coneflower (Echinacea sp.) production in greenhouses and nurseries often relies on commercial fertilizers, such as 20 nitrogen (N)–4.4 phosphorous (P)–16.6 potassium (K), applied at 100 to 200 mg·L−1 N; however, increasing N concentrations proportionately increase phosphorous pentoxide (P2O5) and thus, elemental P concentrations. As such, the recommended N fertilization supplies P concentrations of 21.8 to 43.6 mg·L−1 P, exceeding plant requirements and potentially leading to excessive stem elongation and P runoff, posing ecological risks. Therefore, the objective of this study was to evaluate the effects of P concentrations on the growth, ornamental value, and tissue mineral nutrient concentrations of coneflower (E. × hybrida Sombrero® Granada Gold ‘Balsomold’). A custom soilless substrate was formulated with (by vol.) 55% aged pine bark, 35% sphagnum peatmoss, and 10% perlite, and amended with 0.6 kg·m−3 wetting agent and 3.9 kg·m−3 dolomitic limestone to achieve a final pH of ≈5.6 to 5.8. Young plants of coneflower were individually transplanted into 16.5-cm-diameter (1.7 L) containers filled with the custom soilless substrate. Upon transplanting and throughout the experiment, plants were irrigated with nutrition solutions formulated from technical grade salts providing 0, 2.5, 5, 7.5, 10, 15, 20, or 30 mg·L–1 P. Plants were grown in a glass-glazed greenhouse at 20 °C under ambient daylight supplemented with a photosynthetic photo flux density of ≈120 µmol·m–2·s–1 delivered from light-emitting diode lamps from 0600 to 2200 hr (16-h photoperiod) to achieve a daily light integral of 14 mol·m–2·d–1. At anthesis (≈69 d after transplant), data were collected. In general, plant height, plant diameter, and shoot and root dry weights were significantly influenced by P concentrations, although to different magnitudes. Quadratic plateau models demonstrated plant height, plant diameter, and shoot dry weight were maximized at 52.7 cm, 36.5 cm, and 27.2 g, respectively, with P concentrations of 18.3, 15.9, and 23.4 mg·L−1 P, respectively. Root dry weight demonstrated a positive linear correlation with increasing P concentration where roots were 74% (3.3 g) larger at a P concentration of 30 than 0 mg·L−1 P. Concentrations of ≤ 7.5 mg·L−1 P resulted low (≤ 0.2% P) leaf tissue P concentrations and ≤ 2.5 mg·L−1 P resulted in low-quality plants with incipient symptoms of P deficiency. Collectively, these results indicate that a narrow range of P concentrations may be used to control coneflower growth and mitigate P pollution.
Speakers
avatar for Garrett Owen

Garrett Owen

Extension Specialist and Assistant Professor of Sustainable Greenhouse & Nursery Systems, The Ohio State University
Dr. W. Garrett Owen is Assistant Professor and Extension Specialist of Sustainable Greenhouse and Nursery Production Systems with primary responsibilities in teaching (20%), research (30%), and Extension (50%) in the Department of Horticulture and Crop Science at The Ohio State University... Read More →
Wednesday September 25, 2024 9:00am - 9:15am HST
Nautilus 1

9:00am HST

GG 1 - Population Genetics and Genome-wide Association Studies Provide Insights into the Genetic Basis of Persea Fruit Quality Traits
Wednesday September 25, 2024 9:00am - 9:15am HST
Avocado (Persea americana) is renowned for its high nutritional value and its global consumption is steadily increasing. Currently, only a few cultivars with limited genetic variability are cultivated, and there is a need for developing new avocado cultivars with enhanced horticultural, fruit quality and nutritional traits as well as resistance to diseases and pests. Application of marker assisted selection can significantly accelerate breeding new avocado varieties, which can take 15 - 20 years using traditional breeding methods. Towards the application of molecular markers in avocado breeding, in this report, genome-wide association studies (GWAS) of nine fruit quality traits of a diversity panel of 110 avocado accessions were explored using 4,706 high-quality single nucleotide polymorphisms (SNPs) using multiple models. In addition, genetic diversity and population structure were also investigated, which unveiled three main populations corresponding to the three major avocado botanical races representing Mexican, West Indian, and Guatemalan ecotypes. Phylogenetic study and quantitative genetic analyses suggested a closer relationship between the Guatemalan and West Indian races compared to the Mexican race. Genome-wide association study revealed twelve markers distributed over eleven genomic regions strongly associated with fruit quality traits including fruit color, shape, taste, and skin texture. Annotation analyses of these genomic regions revealed candidate genes affecting these traits. These findings contribute to a comprehensive understanding of the genetic composition of avocado germplasm, which will be useful for identifying genes governing fruit quality traits as well as for accelerating breeding and parent selection efforts in the avocado breeding pipeline.
Speakers
GA

Gul Ali

Geneticist/Lead Scientist, USDA ARS Subtropical Horticulture Research Station
Co-authors
BF

Barbie Freeman

USDA ARS Subtropical Horticulture Research Station
NA
JL

Jin Li

USDA ARS Subtropical Horticulture Research Station
NA
SE

Shamseldeen Eltaher

USDA ARS Subtropical Horticulture Research Station
NA
Wednesday September 25, 2024 9:00am - 9:15am HST
Coral 1

9:00am HST

PGR 1 - PGR applications to reduce HLB-associated preharvest fruit drop in Sweet Orange
Wednesday September 25, 2024 9:00am - 9:15am HST
The Florida citrus industry has seen a steady decline in production since the arrival of Huanglongbing (HLB), or citrus greening disease, in Southern Florida in 2005. Following infection, trees experience a steady decline in health and productivity. HLB has since spread throughout all of Florida’s citrus producing regions resulting in nearly 100% infection rates in traditional field settings. Lamentably, no cure has been found for HLB, so research efforts have focused on mitigating the symptoms associated with this disease. Among the myriad of symptoms associated with HLB, the increased rates of mature fruit (preharvest fruit drop) is a major concern for growers. Not only do more fruit drop in HLB-affected trees, but fruit also begin dropping earlier in affected trees as well. This loss of mature, and potentially marketable, fruit in the months leading up to harvest represents a visual loss of revenue for the growers. The authors have previously reported that the likelihood of a fruit to drop during preharvest fruit drop is related to the size of that fruit; the relatively smaller fruit on the tree are more likely to drop during the preharvest fruit drop window. As plant growth regulators (PGRs) have had promising results in preventing fruit drop in many crop species, the efficacy of PGR applications in reducing preharvest fruit drop was evaluated. Thirty small and thirty large fruit were tagged on four 12-year-old ‘Valencia’ on ‘Swingle’ rootstock trees. Small fruit were those that were a ½ standard deviation below the average fruit size for that tree whereas large fruit were those that were a ½ standard deviation above the average. Ten of the small tagged fruit and ten of the large tagged fruit were then dipped into ProGibb® (33 ppm Gibberellic Acid [GA]), Citrus Fix® (106 ppm 2,4-Dichlorophenoxyacetic Acid [2,4-D]), or left untreated (control). Citrus Fix® improved retention in both small and large fruit whereas ProGibb® only improved retention in the large fruit. As GA prevents drop by delaying the senescence process, the lack of effect in the small fruit may suggest that they have already entered the senescence process. To further explore why the small and large fruit differ in their likelihood to drop and why they respond differently to PGR applications, additional biochemical and molecular analyses are underway.
Speakers
TV

Tripti Vashisth

University of Florida
Co-authors
MP

Maricielo Postillos Flores

University of Florida
NA
MS

Mary Sutton

University of Florida
NA
Wednesday September 25, 2024 9:00am - 9:15am HST
South Pacific 3

9:00am HST

PLAST - Quantum Dot Concentration in Photoconversion Covers Affects Growth Rates of Four Microgreens Species
Wednesday September 25, 2024 9:00am - 9:15am HST
Compared to standard polyethylene agricultural covers, plants grown under quantum dot-infused covers (QD, QDCs) that redshift the light spectrum have exhibited greater yields. While whole-plant and -canopy morphological changes under photoconversion products have been documented, impacts on seedling growth rate (<3 weeks post-germination) are not known. In the current study, four microgreens (alfalfa [Medicago sativa], amaranth [Amaranthus tricolor], kohlrabi [Brassica oleracea var. gongylodes], and pea [Pisum sativum]) were grown in an ebb and flow hydroponic growth chamber under metal halide lamps coupled with QDCs (UV/blue to red/far-red) containing different QD concentrations. Growth measurements derived from image-based phenotyping and traditional, destructive methods were analyzed on a species-specific level. Plants exhibited increased leaf area, biomass accumulation, and growth rate on a species-specific basis. Commercially relevant, it was estimated that some species could be ready for sale days earlier than their control counterparts. Germination rate was not affected significantly.
Speakers
JB

Jeffrey Bates

UbiQD, Inc.
Wednesday September 25, 2024 9:00am - 9:15am HST
Lehua Suite

9:00am HST

QUAL - Inhibiting Foodborne Pathogens and Biofilms on Fresh Produce by Nano-emulsions Developed from Lactobacillus-Derived Exopolysaccharide and Eugenol
Wednesday September 25, 2024 9:00am - 9:15am HST
The proliferation of foodborne pathogens and the formation of biofilms poses a major threat to the food industry, particularly in fresh produce. Raw and minimally processed fruits and vegetables are often sold to consumers in ready-to-use or ready-to-eat forms and are at the forefront of this risk. These products lack preservatives and rarely undergo any heat processing prior to consumption, making them more susceptible to contamination. To address this, we synthesized an oil/water emulsion encapsulating eugenol, using exopolysaccharide extracted from Lactobacillus as a natural emulsifier, and investigated its effectiveness against pathogenic cell populations within biofilm matrices. Different strains of Listeria monocytogenes, Salmonella, and E. coli were studied; results reveal substantial variations in biofilm-forming abilities among different E. coli, Salmonella, and L. monocytogenes strains. Specifically, L. monocytogenes V7 and Scott A strains displayed resistance to the emulsion, resulting in a minimal reduction of 2.8 log CFU/cm2 on the stainless-steel surface within the biofilm. Conversely, other strains exhibited reductions ranging from 3 to 4.5 log CFU/cm2. Most strains’ biofilm inhibition was 85% on plastic surfaces, whereas L. monocytogenes V7, Scott A, and Salmonella enterica ATCC 35664 showed less inhibition. The emulsion was applied to fresh produce (tomatoes, blueberries, and lettuce), where the reduction in E. coli and Salmonella biofilms, along with planktonic cells, varied from 0.53 to 5.1 log CFU/cm2, indicating that the emulsion significantly inhibited the growth of the tested pathogens. In conclusion, the results indicate that biofilm inhibition depends on the microbial species due to the observed individual variation in strains. However, combining eugenol and exopolysaccharide as emulsions is a promising natural alternative and sustainable technology for removing pathogenic biofilms. This research has the potential to advance food safety and hygiene standards, with practical applications in preserving fresh produce and disinfecting surfaces. This work was supported by USDA-NIFA- SCRI- 2017-51181-26834 through the National Center of Excellence for Melon at the Vegetable and Fruit Improvement Center of Texas A
Speakers
SB

SANGEETA BALYAN

Graduate Student, Texas A & M
Co-authors
Wednesday September 25, 2024 9:00am - 9:15am HST
Kahili

9:00am HST

TECH 1 - Effect of Innovative Laser Labeling Technology on Fresh Produce Quality and Safety
Wednesday September 25, 2024 9:00am - 9:15am HST
Introduction: Fresh produce is commonly associated with foodborne disease outbreaks and food recalls. To prevent the lethal impact of outbreaks, effective traceability is crucial. Produce items are traditionally labeled with price lookup (PLU) stickers. However, those stickers are environmental hazards, and frequent detachment of PLU stickers losses the information for traceability. Purpose: To investigate the effect of postharvest quality and microbial safety of laser labeling on fresh produce. Methods: Three horticultural crops, apple ‘Red Delicious ‘apple, cucumber, and green bell pepper, were procured from a local grocery store. Each produce was printed with a Quick Response (QR) code or text code using the laser engraver machine, followed by the application of edible wax. All produce was stored at 4° C temperature and 90% relative humidity during the study period. The postharvest quality was measured through fresh weight loss, QR code readability, and visual quality for 16 days. In another study, the laser-labeled produce was assessed for microbial contamination by quantifying artificially inoculated rifampicin-resistant E.coli (ATCC 25922) at an initial concentration of 106 CFU/mL. The experiment had five treatments: QR-coded labels followed by waxing or no wax, text-coded labels followed by waxing or no wax, and nontreated control. Results: Fresh weight loss for laser-printed produce was slightly higher than the nontreated control, but no difference in visual quality ratings was observed compared to the control. The population of rifampicin-resistant E.coli was statistically higher in all three produce labeled with text code compared to the nontreated control. However, QR-coded treatments were similar in the control. The application of wax did not facilitate microbial attachment. Significance: Laser labeling technology did not deteriorate the postharvest quality and susceptibility to microbial contamination. Hence this technology has the potential in commercial application as a better alternative to the PLU sticker to improve traceability.
Speakers
avatar for Manreet Bhullar

Manreet Bhullar

Kansas State University
Co-authors
DK

Durga Khadka

Kansas State University
NA
EP

Eleni Pliakoni

Kansas State University
MJ

Majid Jaberi Douraki

Kansas State University
NA
PA

Patrick Abeli

Kansas State University
NA
XX

Xuan Xu

Kansas State University
NA
Wednesday September 25, 2024 9:00am - 9:15am HST
South Pacific 2

9:00am HST

VCM 2 - Alternative Carbon Sources Effects on the Soil-plant Nutrient Dynamics During and Post ASD in a High Tunnel Tomato Crop System
Wednesday September 25, 2024 9:00am - 9:15am HST
Anaerobic soil disinfestation (ASD) is a microbial-driven soil disinfestation approach for the management of soilborne pests and pathogens of horticultural crops including protected vegetable production systems increasingly affected by emerging soilborne issues. ASD is implemented by incorporating in the soil an easily labile carbon (C) source, mulching the soil with an impermeable film, and irrigating the soil to field capacity. Organic amendments used as C source also provide N and other nutrients, and research is needed to assess if and how crop fertilization should be adjusted accounting for such nutrients. A study was conducted to evaluate the effect of alternative C sources on soil nutrient availability during and post-ASD in a high tunnel tomato production system. Carbon sources tested included sugarcane molasses, wheat middlings, and soybean meal mixed with wheat middlings. Each C source was applied at the standard rate of 6 Mg/ha of total C. The same C sources were also applied at half rate (3 Mg/ha of total C) balancing the total nitrogen (N) applied to 350 kg/ha of N using composted chicken manure as a source of N. The selected C source treatments were compared with untreated soil amended only with composted chicken manure and an untreated control to estimate the amount of nutrients provided by the untreated soil or by the composted chicken manure. Post ASD, fresh-market tomato cv Red Deuce was planted and used as a test crop evaluating plant growth, nutrient uptake, and yield and quality performance in response to soil treatments. Post-ASD, soil redox potential (Eh) was monitored revealing that all C sources tested determined a significant decrease of soil Eh, suggesting a good efficacy of the ASD treatment. During and post-ASD soil pH, EC, nitrate-N and ammonium-N levels were monitored using soil-water extracts (obtained with the 1:2 v:v method). Significant variation of soil pH, EC and mineral-N content were observed during and post-ASD, which influenced tomato marketable yield. Among the treatment tested WM applied at half rate and balanced for the N which had an intermediate C:N ratio (11.65) provided the highest seasonal marketable yield (10.4 kg/plant), while the untreated control amended with chicken manure provided the lowest yield. Overall, this study suggests that C application rate and the C:N ratio of the organic amendments used to apply ASD have significant effects on the efficacy of the ASD treatment as well as on the availability of nutrients and the crop performance post-ASD.
Speakers
FD

Francesco Di Gioia

Pennsylvania State University
Co-authors
FP

Fritzner Pierre

Pennsylvania State University
NA
Wednesday September 25, 2024 9:00am - 9:15am HST
South Pacific 4

9:15am HST

CE 2 - Stratified Wood Substrates for Optimizing Growth of Greenhouse-Grown Strawberries and Blueberries
Wednesday September 25, 2024 9:15am - 9:30am HST
As the demand for locally grown produce, particularly fresh fruits like blueberries and strawberries, continues to surge, the imperative for year-round production becomes increasingly evident. While these fruits are globally recognized for their extended-season production potential in controlled environments, the intricate environmental factors crucial for improved production and profitability remain partially understood, including the impact of soilless substrates. Amid growing concerns about the availability of internationally sourced substrates, such as coconut coir, this study explores an alternative approach to reduce reliance on such components, particularly in the cultivation of two small fruits rapidly integrated into controlled environments. Substrate stratification, involving the vertical layering of substrates within a single container, has shown promise in nursery and greenhouse settings, enhancing resource efficiency in terms of water and fertilizer inputs. However, no research has assessed the application of stratified substrates for fruit crops with the specific aim of reducing coir inputs in greenhouse production. Thus, the objective of this study was to investigate whether stratifying coir over low-cost, hammer-milled processed tree fiber could effectively decrease coir usage, dependency, and associated costs within the controlled environment fruit production industry. 'Albion' strawberries and 'Star' blueberries were cultivated in five substrate treatments, ranging from 100% coir to various stratified layers beneath coir, including 25%, 50%, and 75% coir compositions, as well as a 100% processed tree fiber treatment. Results suggest that employing substrate stratification enhanced plant growth for both fruit crops, indicating its potential utility in optimizing controlled environment fruit production while reducing reliance on costly substrate materials like coir. Further analysis will elucidate the full implications of this innovative approach on production efficiency and profitability.
Speakers
BS

Brandan Shur

North Carolina State University
Co-authors
BJ

Brian Jackson

NC State
NA
Wednesday September 25, 2024 9:15am - 9:30am HST
Coral 2

9:15am HST

CITR 2/HIST - Physiological and Metabolomic Changes in Young Citrus Trees Under Elevated CO₂ and High Temperatures: A longitudinal st
Wednesday September 25, 2024 9:15am - 9:30am HST
As the atmospheric levels of CO₂ continue to rise, the concentration of carbon sources available for the plants also increases photosynthesis. The rise in atmospheric CO₂ is associated with global temperatures, resulting in an array of plant responses. Studies evaluating plant response to CO₂ treatments of 350 plant species show that plant responses are highly variable and species dependent, with the majority of studies being conducted on vegetable and grain crops, leaving a gap in understanding how tree crops respond. Mandarin (C. reticulata) trees are an economically important crop produced in California subject to climate change. This study used nursery trees of cv. Tango budded on C35 rootstock to determine the effect of elevated CO₂ exposure (400 ppm ambient vs. 800 ppm elevated) at elevated temperature (28°C ambient vs. 45°C elevated) to identify the physiological and metabolomic plant responses associated with each treatment. A longitudinal investigation was conducted over eight weeks in growth chambers (Conviron A1000, Winnipeg, CA) utilizing four treatment groups: ambCO2/Tamb (Control: CO2 400 ppm/Temperature 28°C); eCO2/Tamb (elevated CO2 at 800 ppm/Temperature 28°C); ambCO2/eTemp (CO2 at 400 ppm/Temperature 45°C); and eCO2/eTemp (CO2 at 800 ppm/ Temperature 45°C). Every two weeks, four replicates were collected from each treatment group. physiological measurements, photosynthesis response surveys, and metabolomic analysis were performed. Phenotypic measurements such as plant height, branches, leaf area, and leaf count showed that plant growth was impacted by treatment. Plant height, dry weight, and leaf count were significantly lower in the ambCO2/eTemp treatment as compared to the control (ambCO2/Tamb) as well as the other two treatments, indicating heat stress. Under elevated CO2 levels, trees were able to exhibit similar growth behaviors as the control treatment even under heat stress, signaling that the trees under eCO2 could compensate for a higher burden on carbon balance under heat stress. eCO2/Tamb trees accumulated significantly higher starch than all other treatments, whereas trees under both eTemp treatments showed significantly higher soluble sugars while significantly lower starch levels. This indicates that the trees under supplemental CO2 accumulate higher photoassimilates when they are free from heat stress, and the trees under heat stress exhibit starch conversion to soluble sugars as a stress response. Metabolomics analysis using Nuclear Magnetic Resonance (NMR) will provide valuable insight into the impact of treatment groups of eCO₂ and eTemp impact on Mandarin trees.
Speakers
avatar for Taylor Hornburg

Taylor Hornburg

Graduate Student, california state university
Co-authors
DG

Dave Goorahoo

California State University, Fresno
GB

GURREET BRAR

california state university
VK

Vishvanathan Krishnan

California State University
NA
Wednesday September 25, 2024 9:15am - 9:30am HST
South Pacific 1

9:15am HST

FLOR 1 - Investigating Synergistic Effects of Biostimulants and Biochar on Water Use Efficiency for Containerized Celosia (Argentea cristata) and Gomphrena (Gomphrena globose) Production
Wednesday September 25, 2024 9:15am - 9:30am HST
Given the escalating demands for water and the accompanying scarcity, enhancing water use efficiency (WUE) in horticultural practices has become imperative. Research has revealed that both biochar (BC) and seaweed extract biostimulants (BS) significantly enhanced WUE in plant growth, presenting promising avenues for sustainable agricultural advancement. This study aimed to investigate the synergistic effect of BC and BS on WUE for celosia (Argentea cristata) and gomphrena (Gomphrena globose) production. Three factors were included in this experiment including 1) mixed hardwood biochar blended with commerical substrate mixes (CS) at 0%, 10%, 15%, and 25% 2) 60% or 80% irrigation and 3) 0 or 5 mL BS(seaweed extract). The physical properties of substrate, including container capacity (CC), total porosity (TP), air space (AS), bulk density (BD), and water holding capacity (WHC), and chemical properties including leachate pH and electrical conductivity (EC) were measured. Plant growth parameters including growth index (GI) and leave greenness (indicated with SPAD value), biomass, and numbers of flowers were measured biweekly. Photosynthesis rate, transpiration rate, and stomatal conductance rate were measured at 6, 7, 8 WAT. The results showed that BC rates had significant effects on CC, and BD, but no effects on either TP, AS or WHC. Celosia plants grown in the 25% BC mix treated with 5mL BS at 80% irrigation had significantly higher biomass and WUE, and both plants in the same mix (25
Speakers
avatar for Lilin Chen

Lilin Chen

Graduate Research Assistant, University of Georgia
I'm interested in biochar effect on containerized plants, especially the effect under abiotic stresses such as drought and salinity.
Co-authors
PY

Ping Yu

University of Georgia
YC

Yulong Chen

The University of Georgia
Wednesday September 25, 2024 9:15am - 9:30am HST
Nautilus 1

9:15am HST

GG 1 - Genome Assembly of Persia Americana cv. Simmonds Provides Insights on Genetic Relationships Among Avocado Hybrids Exhibiting Tolerance To Laurel Wilt
Wednesday September 25, 2024 9:15am - 9:30am HST
Avocado (Persea americana) is the major fruit cultivated in southern Florida counties with a value exceeding 20 million dollars annually. While production in other regions is dominated by the Hass cultivar, south Florida is unique in production of the increasingly popular, green-skinned varieties. Recently, the avocado industry in South Florida has been devastated by laurel wilt (LW), an insect-disease complex spread by Raffaelea lauricola (Rf), a fungal symbiont of redbay ambrosia beetle (Xyleborus glabratus Eichhoff). Current management practices including prophylactic fungicide injections, tree rejuvenation and ambrosia beetle population reduction are costly and onerous . Unfortunately, no mature avocado trees tolerant to LW are available to growers and genetic mechanism of LW tolerance observed in some avocado seedlings is unknown. In this study, a chromosomal genome of avocado cv. ‘Simmonds’, a ‘West Indian’ (Lowland) ecotype was assembled from Pacific Biosciences HiFi reads. The genome assembly contained 451 scaffolds spanning 98.89% of the avocado genome, a N50 of 82.34MB and a BUSCO score of 95%. This assembly served as a reference genome to generate 9198 genome wide single nucleotide polymorphisms (SNPs) using genotyping by sequencing (GBS) reads of a germplasm collection comprising 80 accessions of three avocado ecotypes (Mexican, Guatemalan and West Indian) and 18 novel hybrids exhibiting seedling tolerance to LW. Phylogentic analyses revealed three major clusters with majority of LW tolerant seedlings clustering amongst Hass derived hybrids as well as cultivars belonging to Mexican and Guatemalan ecotypes such as 'Winter Mexican', and 'Ettinger'. This work provides genomic resources for characterization of genetic tolerance of LW in avocado germplasm collections and is a significant step in developing LW tolerant hybrids to support local avocado industry.
Speakers
VN

Vincent Njung'e Michael

University of Florida
Co-authors
JH

Jonathan H Crane

University of Florida, TREC
RG

Romina Gazis

University of Florida
NA
XW

Xingbo Wu

University of Florida
NA
Wednesday September 25, 2024 9:15am - 9:30am HST
Coral 1

9:15am HST

PGR 1 - Ethephon Effect on Blooming of Three Southern Highbush Cultivars
Wednesday September 25, 2024 9:15am - 9:30am HST
Spring frost is the primary cause of yield reduction in southern highbush, representing a significant challenge to blueberry production in the southeastern United States. Plant growth regulators are used as aids in different agricultural industries to either advance or delay growth and development process. Ethephon influences fruit set, size, and yield and has also been used as a tool to delay bloom in order to avoid freeze damage. This study examined the efficacy of ethephon to delay flower bud growth stages in three Southern Highbush Blueberry cultivars (‘Farthing’, ‘Georgia Dawn’, and ‘Kee Crisp’). Ethephon was applied at different concentrations of 200, 400, and 800 ppm, and a control treatment water/surfactant was also included. Flower buds were visually assessed from January until March. No relevant results were found for ‘Farthing’; however, for ‘Georgia Dawn’ and ‘Kee Crisp', ethephon at 800 ppm had the highest effect on delaying blooming development compared to the control. These results suggest that ethephon might delay flower bud growth stages in Georgia Dawn and Kee Crisp, offering potential advantages in reducing susceptibility to spring chill injury.
Speakers
LC

Lilian Carcamo

University of Georgia
Co-authors
MC

Mark Czarnota

University of Georgia
NA
MB

Melissa Brannon

University of Georgia
NA
ZR

Zilfina Rubio Ames

University of Georgia
Wednesday September 25, 2024 9:15am - 9:30am HST
South Pacific 3

9:15am HST

QUAL - Evaluating Nutritional Quality and Consumer Acceptability of Lettuce (Lactuca sativa L.) Grown with a Movable High Tunnel
Wednesday September 25, 2024 9:15am - 9:30am HST
Light quality is known to affect the growth and phytochemical content of numerous crops, including lettuce (Lactuca sativa L.). High tunnel production of lettuce provides many benefits to growers including increased yield due to higher soil temperatures and protection from abiotic stressors, such as strong wind and heavy rains. However, the use of UV-blocking polyethylene films can also result in lower antioxidant capacity and phenolic content, leading to a decrease in nutritional quality compared to lettuce grown in the open-field. Movable tunnels provide the ability to expose the crop to full-spectrum light once the crop has grown to full size. Our objective was to identify management strategies to optimize yield, phytochemical production, color, safety, and consumer acceptability of red-leaf cultivar (‘New Red Fire’). Lettuce was planted in a movable high tunnel April 2022 and exposed to 0, 2, 7, or 14 days of full sun prior to harvest. Total marketable yield, leaf color (L*a*b* color space), total phenolic content (TPC) and anthocyanin content were measured at harvest. Lettuce consumers (N=100) were asked to rate overall liking and various sensory attributes using continuous intensity scales, CATA, and open-ended comments. Total marketable yield and TPC were not affected. Leaf redness (a*) and anthocyanin content were significantly higher after 14, 7, and 2 days of full-sun exposure compared to 0 days. Significant differences were found in consumer liking for overall liking, color intensity, and ruffleness. The crop that was exposed to 14 days of full-spectrum light had a higher liking and more red color intensity. Using a movable tunnel system provides lettuce growers the ability to affect the color, phytochemical content, and consumer liking of their crop to varying degrees. This level of flexibility provides local, small-scale growers a crucial advantage in marketing their produce.
Speakers
CR

Cary Rivard

Kansas State University
Co-authors
EP

Eleni Pliakoni

Kansas State University
MB

Manreet Bhullar

Kansas State University
MT

Martin Talavera

Kansas State University
NA
OH

Olivia Haley

Kansas State University
NA
PA

Patrick Abeli

Kansas State University
NA
TJ

Tricia Jenkins

Kansas State University
Wednesday September 25, 2024 9:15am - 9:30am HST
Kahili

9:15am HST

TECH 1 - Cover Crop Decision Support Tools: Exploring the new suite of online cover crop tools
Wednesday September 25, 2024 9:15am - 9:30am HST
Cover crop recommendations can be complex based on regional factors and different growing conditions. In order to combat these challenges, the Precision Sustainable Agriculture team (PSA) developed online tools that are readily available for producers to help them optimize cover crops on their operation. Tools include a species and variety selector tool, seeding rate calculator, nitrogen calculator, and economic decisions tool. These platforms look to help producers find success with cover crops that fit their operation’s needs.
Speakers
EH

Esleyther Henriquez Inoa

Research Assist., North Carolina State University
Technologies in agriculture and Cover Crop breeding. 
Co-authors
SM

Steven Mirsky

USDA ARS BARC
NA
Wednesday September 25, 2024 9:15am - 9:30am HST
South Pacific 2

9:15am HST

VCM 2 - Advancing Pepper Production Beyond Seasonal Limits: Findings from a High Tunnel System Integrated with Biostimulant Applications
Wednesday September 25, 2024 9:15am - 9:30am HST
Pepper is an important specialty crop in the Southwest U.S., cherished for its economic importance, cultural history, and high nutritional values. Despite being a leading pepper producer in the U.S., challenges such as high temperatures, erratic weather patterns, and imports from Mexico have hindered both production and profitability of growers in this region. In response, alternative systems like high tunnels have emerged as viable solutions. The mild winter climate in Southwest Texas offers an ideal setting for winter pepper cultivation in high tunnels, potentially boosting growers' profitability with off-season market opportunities. Application of biostimulants, such as seaweed extracts, holds promise in enhancing cold tolerance and transplant success within high tunnel systems. This study investigates the feasibility of winter pepper production in high tunnels established in the Wintergarden region, assessing various cultivars based on yield and quality. The high tunnel maintained a range of 8-10°C higher temperatures than the open-field on chilly days without additional heating. Seven pepper cultivars were evaluated, with and without seaweed extracts. Seaweed-treated plants exhibited an overall higher stomatal conductance and leaf transpiration rates along with reduced leaf electrolyte leakage. Rio de Oro; a Santa Fe type pepper had the highest PSII efficiency and total fruit yield. Seaweed application also increased total yield and individual fruit weight in cultivar-specific manner. The total phenolic content of fruits was increased by seaweed application at the early maturity stage whereas total flavonoid content varied by cultivar and maturity stage. Despite facing freeze challenges at the early transplant stage, this first-year experiment demonstrated promising potential for off-season pepper production in high tunnels in our region.
Speakers
AN

ASMITA NAGILA

Graduate Research Assistant, Texas A&M university
Co-authors
Wednesday September 25, 2024 9:15am - 9:30am HST
South Pacific 4

9:29am HST

Temperate Tree Nut Crops 1 (NUTS 1)
Wednesday September 25, 2024 9:29am - 11:00am HST
Can Hedge-Pruning Reduce Water Needs In Southeastern United States Pecan Orchards? - Bailey Rayfield
Leaf Anatomical Traits and Water Use Efficiency in Four Pecan Cultivars - Sarahi Bracamontes
Performance of Five Early-harvest Pecan Cultivars in South Georgia - Patrick Conner
Enhancing Pecan Tree Resilience Against Spring Freeze Events: Insights from Secondary Bud Dynamics and Carbohydrate Analysis - Lu Zhang
Biochar in Pecan Orchards: Unraveling Water Stress Dynamics for Sustainable Irrigation Management - Jamin Miller
Evaluating Soil Management Impacts on the Pecan Orchard Mycobiome in the Semi-Arid Southwestern United States - McKenzie Stock
Moderator
PC

Patrick Conner

University of Georgia
Wednesday September 25, 2024 9:29am - 11:00am HST
Lehua Suite

9:30am HST

CE 2 - Effect of Light Intensity on Strawberry Runner Tips Propagated Indoors
Wednesday September 25, 2024 9:30am - 9:45am HST
Indoor propagation systems that use sole-source lighting in controlled environments can facilitate year-round production of disease-free, uniform strawberry liners. However, optimal conditions to propagate strawberry runner tips indoors are unknown. Runner tips of ‘Albion’ and ‘Fronteras’ strawberries were propagated indoors for 28 d under four photosynthetic photon flux density (PPFD) treatments: 75, 150, 225, or 300 ± 5 μmol·m–2·s–1 provided for 24 h·d–1 by white light-emitting diode fixtures. Runner tips were also propagated in a shaded greenhouse under mist. After propagation, plants were moved to a common greenhouse compartment and grown for 7 weeks to evaluate carryover effects on fruit yield (‘Albion’) or daughter-plant production (‘Fronteras’). Treatment responses were similar for both cultivars, except that shoot dry mass (DM) of ‘Fronteras’ followed a quadratic response with increasing PPFD, which peaked at 225 μmol·m–2·s–1. In contrast, shoot DM of ‘Albion’ linearly increased with increasing PPFD. Root DM of both cultivars also followed an increasing response with PPFD. However, there were no treatment differences in the number of shoots produced per plant or the length of the longest root. Interestingly, plants propagated under ≥150 μmol·m–2·s–1 had several dead shoots (up to 20%), likely attributed to plant stress. After the carryover phase, ‘Albion’ propagated under 225 or 300 μmol·m–2·s–1 were statistically different and produced the lowest fruit fresh mass compared to those grown in the greenhouse, whereas values were similar among plants propagated in the greenhouse or indoors under 75 or 150 μmol·m–2·s–1. No treatment differences were measured in the number of daughter plants produced by ‘Fronteras’. These findings suggest that although higher PPFD indoors promoted rooting and growth, plants propagated in the greenhouse were likely better adjusted to the dynamic greenhouse environment, which enabled them to reach the same growth and development of indoor-propagated plants at the end of the carryover phase.
Speakers
LD

Lian Duron

Purdue University
Wednesday September 25, 2024 9:30am - 9:45am HST
Coral 2

9:30am HST

CITR 2/HIST - Reports and research on incorporating cover crops in Florida citriculture, 1896 – 2024
Wednesday September 25, 2024 9:30am - 9:45am HST
Florida is perhaps the state in the U.S. most identified with citrus cultivation. The warm winters, abundant sunshine and significant rainfall are qualities which promote this industry, although other factors make producing these fruits on larger groves more arduous. These include limited nutrient concentrations, problematic drainage dynamics, and low organic matter and cation exchange capacity. Such issues combine to make citrus production in Florida highly dependent on external inputs of labor and material, both of which can be financially burdensome and demonstrate high volatility in price or availability from year to year. Cover crops have the potential to cost-effectively amend many soil issues in Florida citrus groves if they are established and maintained according to certain management practices. This principle was first presented at the Florida State Horticultural Society meeting in the late 1890s, and then clarified by Harold Hume in Citrus Fruits and their Culture in 1904. Later, the non-native legumes Crotolaria pallida and Crotolaria juncea were identified in multiple publications as soil-building cover crops which could be implemented into Floridian citrus production. Florida’s citrus production in the wake of World War II saw a decline in its incorporation of legume cover crops in favor of synthetic fertilizers. More modern research initiatives in Florida focused primarily on the mitigation of transmissible disease like Phytophthora root rot and citrus canker, a trend which has become more apparent following the discovery of citrus greening in 2005 and the stark decreases in yields this bacterial illness has been the primary cause of. In response, a number of Florida citrus growers have adopted cover crop mixes featuring legumes to supply disease-afflicted citrus roots with a sustainable and regular source of nitrogen. This presentation will review past literature and will also discuss current research on legume cover crops that have the potential to bolster citrus operations which is being conducted by individuals in the state of Florida.
Speakers
avatar for Lorenzo Rossi

Lorenzo Rossi

Assistant Professor, University of Florida
Dr. Rossi’s research program focuses on improving root health and growth on cultivated crops, leading to the development of environmentally sound and effective management methods. He is a horticulturist with specific expertise related to plant stress physiology, root dynamics and... Read More →
Co-authors
JP

Joseph Paoli

University of Florida
I am a Master's student at the University of Florida based at the Indian River Research and Education Center (IRREC). I am a long-time Florida resident, having gone to Middle and High School in Central Florida before enrolling at the University of Florida. During my four years of... Read More →
LH

Lukas Hallman

University of Florida
Wednesday September 25, 2024 9:30am - 9:45am HST
South Pacific 1

9:30am HST

FLOR 1 - Effects of Reduced Water Usage During Production on Economic Value, Growth, And Quality of Flowering Indoor Plants
Wednesday September 25, 2024 9:30am - 9:45am HST
The objective of this study was to investigate the effects of soil moisture content during greenhouse production of selected floriculture crops. Over the course of several seasons, multiple flowering species were investigated, including Euphorbia milii, Cyclamen persicum, and Begonia x tuberhybrida. Plant quality characteristics were evaluated both during the production timeframe, and after a simulated shipping and retail setting. Treatments included two soil moisture content levels (20% and 40%), which was monitored by soil moisture probes. Production timelines varied, due to the differences in species. Once the predetermined production weeks were concluded the plant went into simulated shipping and retail environment. Qualities such as growth index (GI), leaf greenness (SPAD), Leaf thickness, petiole thickness, irrigation events, and irrigation amount were measured weekly. Flower number and foliage fresh /dry weights were gathered after the two week simulated retail period. Results varied depending on the species. In all species the 20% group had less watering events, which equates to producer savings in fertigation inputs as well as labor. All species had reduced canopy size in the 20% treatment, which could equate to bench space conservation. Some of the plant quality characteristics depending on the species had similar results after simulated retail. This equates to the idea that producers could reduce water application events and volumes and generate an equal quality plant compared to the traditional watering methods, while also saving on input and labor costs.
Speakers
KH

Kaitlin Hopkins

Sam Houston State University
Wednesday September 25, 2024 9:30am - 9:45am HST
Nautilus 1

9:30am HST

GG 1 - Utilizing Haploid Pollen Grains and Diploid Leaf Tissue Genomic Sequence Data to Phase the ‘Wonderful’ Pomegranate Genome
Wednesday September 25, 2024 9:30am - 9:45am HST
The scientific and commercial interest in pomegranate (Punica granatum L.) cultivation has increased noticeably during the last two decades. Because of the high concentration of bioactive compounds and its nutraceutical properties, pomegranate has been defined as a super food. The consumption of pomegranate juice or arils has been related to several possible benefits on human health. Recent studies have highlighted an antioxidant and anti-inflammatory activity of this fruit which seem to prevent cardiovascular, neoplastic, neurological, metabolic, and intestinal disease. The areas of cultivation of this crop are exposed to current and future challenges like long term-drought conditions and invasive pests and diseases. Increasing the biodiversity of pomegranate has been proposed has the main strategy to reduce the risk of food system vulnerability related to monoculture and the valorization of marginal land. In order to develop advanced genetic tools to improve pomegranate breeding program efficiency we present the de novo sequencing of the ‘Wonderful’ pomegranate genome. DNA isolated from diploid leaf tissues was sequenced using long read sequencing technology (PacBio), while DNA extracted from haploid pollen grains was sequenced using short reads (Illumina). Genomic data from single haploid gamete cells were analyzed using the R package called ‘Hapi’. This allowed to infer chromosomal haplotypes obtaining a higher resolution for DNA variants detection and investigating recombination events in single gametes. Although ‘Wonderful’ represents the industry standard in the United States, several cultivars with desirable traits, such as low acidity and soft seednesses, have been identified in the national germplasm. The results of this study will provide the genomic data required to investigate differences among cultivars and create trait-gene associations. This will allow breeders to facilitate the integration of desired quality traits into new germplasm resources.
Speakers
GL

Giuseppe Lana

University of Florida
Co-authors
DS

Danelle Seymour

UC-Riverside
NA
DM

Donald Merhaut

UC-Riverside
NA
HQ

Han Qu

UC-Riverside
NA
JC

John Chater

University of Florida
MR

Mikeal Roose

UC-Riverside
NA
RT

Ryan Traband

UC- Riverside
NA
TB

Taylor Beaullieau

UC-Riverside
NA
ZJ

Zhenyu Jia

UC-Riverside
NA
Wednesday September 25, 2024 9:30am - 9:45am HST
Coral 1

9:30am HST

NUTS 1 - Can Hedge-Pruning Reduce Water Needs In Southeastern United States Pecan Orchards?
Wednesday September 25, 2024 9:30am - 9:45am HST
Pecan (Carya illinoinensis) trees have experienced higher density plantings which enhances the need for better water use efficiency to increase the sustainability of the orchard. The implementation of hedge-pruning allows for better light penetration as well as more efficient water use in the humid climate of the southeastern United States. The objectives of this study were to determine if irrigation rates can be reduced on hedge-pruned pecan trees with no loss in pecan yield or nut quality. The study is a split-plot design with pruning serving as the main plot effect and irrigation serving as the split plot effect. On hedge-pruned trees, all growth beyond 8’ from the trunk on the East side of the tree was pruned in year 1 and on the West side of the tree in year 2. Trees were topped on each side in their respective years at an angle with a peak at 40’. No pruning will be done in year 3. Hedging treatments are arranged in three tree blocks with each irrigation treatment occurring once per block as follows: 1) 100% irrigation; 2) 50 % irrigation; 3) non-irrigated control. Hedged blocks were replicated four times, and the non-hedged blocks were replicated three times. Among the irrigation regimes, there was no statistical difference between treatments indicating that, under the environmental conditions observed, less water is sufficient for pecan production, regardless of pruning treatment. Although, there has been no improvement in yield from the hedge-pruned trees, percent kernel has increased in the hedged trees compared to the non-hedged trees, suggesting an enhancement of pecan nut quality with hedge pruning.
Speakers
BR

Bailey Rayfield

University of Georgia
Co-authors
LW

Lenny Wells

University of Georgia
NA
Wednesday September 25, 2024 9:30am - 9:45am HST
Lehua Suite

9:30am HST

PGR 1 - Development of a Tissue Culture Approach for Doubling the Ploidy Level of Southern Highbush Blueberry Varieties
Wednesday September 25, 2024 9:30am - 9:45am HST
Increased consumption of blueberries has led to a prominent rise in demand. However, Georgia blueberry production is limited by challenges including short orchard life of southern highbush (SHB; tetraploid) and fruit quality issues associated with rabbiteye (RE; hexaploid) varieties. Interspecific hybridization can bring in beneficial alleles to improve the local adaptability and fruit quality of commercial varieties. Many of the wild blueberry germplasm with valuable soil adaptability and fruit quality traits such as V. fuscatum are diploids. Heteroploid crossings between SHB and diploid wild blueberry were shown to have a very low level of success. Ploidy induction through tissue culture is promising to circumvent the ploidy barrier and improve the efficiency of wide-hybridization. The objective of this research focuses on developing a ploidy induction protocol using two SHB varieties ‘Emerald’ and ‘Rebel’. SHBs previously initiated in tissue culture, were treated with 0%, 0.02% and 0.2% colchicine. SHBs were segmented into single and double node segments and put into woody plant medium (WPM) culture media containing either 6-(γ,γ-Dimethylallylamino)Purine (2iP) or trans-Zeatin. The treatments, along with non-treated control, were grown in a growth chamber of 26°C with 16/8 day and night cycles. The number and length of new shoots were recorded 35 and 50 days after treatment (DAT). Significant longer axillary stem growth was observed in the non-treated control compared to that of colchicine-treated segments for both SHBs indicating the suppressive effect of stem growth from colchicine treatments. Several Octo- and mix ploidy-shoots of ‘Emerald’ and ‘Rebel’ were identified among colchicine-treated SHB explants after ~ 21 weeks using a flow cytometer. Both levels of colchicine treatments generated octoploids. These new synthetic octoploid blueberries will be useful to cross with SHB and RE blueberries. The established ploidy induction protocol will be utilized to double the chromosomal levels of diploid V. fuscatum species and make them cross-compatible with SHB varieties.
Speakers
EW

Emily Walter

University of Georgia
Co-authors
YC

Ye Chu

University of Georgia
NA
Wednesday September 25, 2024 9:30am - 9:45am HST
South Pacific 3

9:30am HST

TECH 1 - CFD-based aerodynamic analysis under high wind velocity environment for multiple greenhouses
Wednesday September 25, 2024 9:30am - 9:45am HST
In South Korea, approximately 65% of the land is mountainous or forested, which limits large-scale farming. Over 53,000 ha of land has been reclaimed from the sea and dedicated to the development of large-scale indoor agricultural complexes. Given the coastal climatic conditions and flat nature, these areas present unique challenges including stronger winds and colder temperatures compared to the inland, leading to high air velocities and operation costs in naturally ventilated greenhouses. Aerodynamic analysis is necessary to estimate crop risk factors and identify potential aerodynamic problems before the construction of these structures. Traditional studies have focused on using natural ventilation rates to estimate greenhouse suitability for plant growth. However, under scenarios of high wind velocity, this approach has critical limitations in accounting for crop damage resulting from high air velocity induced inside naturally ventilated facilities. This is tailored to the fact that ventilation efficiency in naturally ventilated structures increases with an increase in air velocity. High wind velocity induced inside greenhouses is associated with rapid CO2 depletion, stomatal dysfunction, leaf abrasion, mechanical stress etc., which critically affect crop yield and biomass development. Under high wind environment, crop damage resulting from high internal air velocities is an important factor that needs to be accounted for during design of indoor agricultural facilities. This study introduces a CFD model for designing greenhouse complex including multiple greenhouses and model analysis approach. We developed the Aerodynamic Crop Damage Index (ACDI), used it to analyze the model, and compared it to the convectional ventilation efficiency approach. The ACDI revealed a 2.2-fold variation in damage potential based on the greenhouse's location within the complex and a 15-fold variation attributable to wind direction, pinpointing significant damage risks in zones with the highest and lowest air velocities. In contrast, the convectional ventilation efficiency method only identified damage risks in low-velocity areas. ACDI has not only the potential to account for high air velocity effects in naturally ventilated greenhouses but also presents an opportunity for specialized greenhouse complex control and management according to greenhouse position and incoming wind direction. Future research should aim at refining the ACDI for better aerodynamic analysis in greenhouse complexes planning and its integration into greenhouse ventilation control systems.

Acknowledgments: This work was supported by “Regional Innovations Strategy (RIS)” through the National Research Foundation of Korea (NRF) funded by Ministry of Education (MOE) (2024RIS-008)
Speakers
AK

Anthony Kibwika

Jeonbuk National University, Korea
Co-authors
Wednesday September 25, 2024 9:30am - 9:45am HST
South Pacific 2

9:30am HST

VCM 2 - Optimizing Nitrogen Fertilizer Rate and Planting Density of Vidalia Onion Yield and Bulb Size Distributions
Wednesday September 25, 2024 9:30am - 9:45am HST
This study was carried out at the University of Georgia (UGA) Vidalia Research Center during the 2022/2023 winter season and is being repeated in 2023/2024. The objectives of this experiment were to identify the relationship between planting density, nitrogen fertilizer rates, and the effects on yields and bulb size distribution. The variety “Sweet Magnolia” was tested at three planting densities (116,000; 87,000; and 58,000 plants per acre) and three nitrogen rates (120, 100, and 80 lbs. per acre). Results indicated there is no interaction between planting density and nitrogen rates on onion bulb size distribution or total production. However, the effect of planting density was significant. Higher densities (116,000 plants/acre) yielded a total weight of 1788 40 lbs. bags/acre with a significant proportion of jumbo-sized bulbs 62%, while lower densities (58,000 plants/acre) resulted in larger colossal bulbs 290 40 lbs. bags/acre with a reduced total yield 1370 40 lbs. bags/acre. Nitrogen application also had a significant impact on both yield and size of the bulb. The highest nitrogen rate (120 lbs./acre) produced a higher total yield (1670 40 lbs. bag/acre), with a significant portion of jumbo at 50% and colossal bulbs at 15%. There was no significant difference between the nitrogen rates of 100 and 120 lbs./acre, but the lowest nitrogen rate (80 lbs./acre) had the worst yield with 1434 40 lbs. bags/acre resulting in a 15% decreased yield compared with the higher rate. These results suggest that optimal planting density and nitrogen application are decisive for reaching the desired bulb size distribution and maximizing yield.
Speakers
EP

Elvis Pulici

University of Georgia
Co-authors
HY

Henry Y Sintim

University of Georgia
NA
JC

Juan Carlos Diaz Perez

University of Georgia
TM

Ted McAvoy

University of Georgia
NA
Wednesday September 25, 2024 9:30am - 9:45am HST
South Pacific 4

9:44am HST

Viticulture and Small Fruits 2 (VSF 2)
Wednesday September 25, 2024 9:44am - 11:30am HST
Evaluation of Pierce's Disease-resistant Grapevine Cultivars in South Carolina - Annie Bruno
Diversity and Abundance of Bees Visiting Grape Flowers in Wisconsin Vineyards - Christelle Guedot
The Grape Health Index: Validation of a New Methodology for Quantifying Wine Grape Spoilage by Means of FT-MIR Spectroscopy - Sonet Van Zyl
Transcriptome Analysis of Muscadine Pedicels Reveals Candidate Genes Modulating the Fruit Abscission Process - Alana Brinley
World Grape Rootstocks Pedigree Review - Alireza Rahemi
Genome Database for Vaccinium: Genomics Data and Tools to Facilitate Research - Jodi Humann
Use of Glycine Betaine and Kelp Extract Mitigates Heat Stress in Red Raspberry (Rubus idaeus) - Givemore Munashe Makonya

Moderator
SV

Sonet Van Zyl

Fresno State
Wednesday September 25, 2024 9:44am - 11:30am HST
Kahili

9:45am HST

CE 2 - Characterizing the Growth, Morphology, Productivity, and Fruit Quality of Twenty-five Strawberry Cultivars in Vertical Farm Environment
Wednesday September 25, 2024 9:45am - 10:00am HST
As the interest in strawberry production in controlled environment agriculture is ascending, the demand for cultivars that yield premium-quality fruit is rising. To identify strawberry suitable for vertical farm production, 25 strawberry (Fragaria × ananassa) cultivars were selected for premium flavor from USDA National Clonal Germplasm Repository. Fruit productivity and quality traits, plant vegetative phenotypes, and photosynthetic rates were evaluated using strawberries grown in a walk-in growth chamber where photoperiod altered between short day and long day to promote flowering and fruit production. Our results show that strawberry ‘Mara des Bois’ produced the earliest harvest, and ‘Hood’ had the highest maximum productivity coefficient. The largest fruit was produced by ‘Chandler’, and the reddest fruit was produced by ‘Marshall’. Among the 25 cultivars, 11 exhibited fruit Brix levels above 0.9, and 3 had a fruit Brix:TA ratio of 1.0. Ongoing fruit flavor analysis aims to identify unique flavor compounds within these strawberries. Correlations linked time to first harvest and maximum productivity coefficient with canopy area, shoot height, and photosynthetic rate per plant, revealing the intricate sink-source dynamics in strawberry plants. Interestingly, no correlation was found between maximum productivity coefficient and any fruit quality trait, challenging the commonly held belief in the constant competition between crop productivity and quality. The information of strawberry growth and production in vertical farm environment provided in this study can assist indoor growers in cultivar selection and potentially contribute to future strawberry breeding programs.
Speakers
YL

Yiyun Lin

The Ohio State University
Co-authors
CK

Changhyeon Kim

The Ohio State University
NA
CK

Chieri Kubota

The Ohio State University
NA
JO

Jim Oliphant

US Department of Agriculture
NA
MH

Michael Hardigan

US Department of Agriculture
NA
NB

Nahla Bassil

US Department of Agriculture
NA
Wednesday September 25, 2024 9:45am - 10:00am HST
Coral 2

9:45am HST

NUTS 1 - Leaf Anatomical Traits and Water Use Efficiency in Four Pecan Cultivars
Wednesday September 25, 2024 9:45am - 10:00am HST
The leaf surface and interior structure can affect photosynthesis and transpiration rates associated with water use efficiency. Several studies have assessed pecan (𝘊𝘢𝘳𝘺𝘢 𝘪𝘭𝘭𝘪𝘯𝘰𝘪𝘯𝘦𝘯𝘴𝘪𝘴) leaf anatomical traits and established differences between cultivars; however, the effect of these traits on water use efficiency across cultivars has not been established. Understanding the relationship between leaf anatomical structures and water use efficiency across pecan cultivars allows for the identification of those that are well suited for water limited environments. In this study, we examined the leaf mesophyll layer thickness (µm), trichome density (trichome mm⁻²), stomatal density (stomata mm⁻²), and stomatal pore area (µm²) of four pecan cultivars (‘Wichita’, ‘Western’, ‘Pawnee’, and ‘Lakota’; all grafted to clonally propagated rootstocks). Leaves were collected at the NMSU Leyendecker Plant Science Research Center, and their cross-section and abaxial surface were imaged using light and scanning electron microscopy, respectively. ‘Lakota’ leaves had the thinnest palisade mesophyll layer and thickest spongy mesophyll layer relative to total leaf thickness. The stomatal density of ‘Pawnee’ was significantly less than the other cultivars, but no significant differences in stomatal pore area were observed. Intrinsic water use efficiency, calculated as ratio of the carbon assimilation rate to stomatal conductance to water vapor, was obtained using a leaf gas exchange meter on three separate days. A stable carbon isotope composition analysis was also conducted to provide insight into the leaf’s longer-term water use efficiency. The results showed that the intrinsic water use efficiency of ‘Lakota’ was different from ‘Western’ on one of the days; however, differences between cultivars were not significant when averaged across the measurement dates. Furthermore, the relative ¹³C abundance and ¹³C discrimination did not have significant differences across the four pecan cultivars evaluated, suggesting that differences in leaf anatomical traits did not influence the water use efficiency of these samples.
Speakers
SB

Sarahi Bracamontes

New Mexico State University
Co-authors
CV

Ciro Velasco-Cruz

New Mexico State University
NA
JR

Jennifer Randall

New Mexico State University
NA
KG

Kanchan Grover

New Mexico State University
NA
RH

Richard Heerema

New Mexico State University
NA
SB

Samy Belteton

New Mexico State University
NA
Wednesday September 25, 2024 9:45am - 10:00am HST
Lehua Suite

9:45am HST

VCM 2 - Assessing the Efficacy of Plant Biostimulants on Onion Growth and Production in Greenhouse Trials and Field Conditions
Wednesday September 25, 2024 9:45am - 10:00am HST
The escalating impacts of climate change on agriculture necessitate the exploration of sustainable crop enhancement methods. This research integrates greenhouse screening and field application to evaluate the efficacy of biostimulants in promoting the growth of onion (Allium cepa L.) under variable environmental conditions. In the initial greenhouse experiment, seven biostimulants were tested, including three bacterial products (Continuum, Spectrum DS, and Tribus Original), two mycorrhizal products (Mighty Mycorrhizae and Myco Apply), one seaweed extract product (Seaweed), and one product containing humic acid (Huma Pro 16). These were applied to assess their impact on seedling emergence and growth in a peat-based soilless substrate. Huma Pro 16 and Spectrum DS were identified as the most effective in increasing seedling emergence, leaf area, and biomass. Based on these findings, field trials were conducted with four onion cultivars (red, sweet, white, and yellow), subjected to conditions simulating drought and normal watering (75 % and 100 % evapotranspiration) or with nitrogen levels adjusted to low and high (75 % and 100 % of optimal 168 kilograms per hectare). The field trials assessed bulb diameter, weight, and leaf metrics. Results indicated that cultivars responded differently to varying conditions, with red and white onions showing consistent growth patterns, while sweet onions displayed more variability. Yellow onions benefited from the biostimulants, exhibiting improved growth under both drought and low nitrogen conditions. This study demonstrates that the application of certain biostimulants can significantly enhance crop growth and resilience. Huma Pro 16 and Spectrum DS show promise for improving onion yield in the face of climatic challenges. Keywords: biostimulants, drought stress, nitrogen availability, onion, and sustainable agriculture.
Speakers
PN

PRAKRITI NEPAL

Utah State Univeristy
Co-authors
DT

Daniel T Drost

Utah State University
NA
YS

Youping Sun

Utah State University
Wednesday September 25, 2024 9:45am - 10:00am HST
South Pacific 4

9:45am HST

VSF 2 - Evaluation of Pierce's Disease-resistant Grapevine Cultivars in South Carolina
Wednesday September 25, 2024 9:45am - 10:00am HST
Recently, there has been an increased interest in wine grape (Vitis vinifera) production in South Carolina (SC). The warm and humid climate in SC creates a conducive environment for a high risk of disease incidence. Despite the typical climate, SC has droughts periodically. Pierce’s Disease (PD), caused by the xylem-limited bacterium Xylella fastidiosa (Xf), is a major limiting factor to grapevine cultivation throughout the United States and, specifically, in the southeastern U.S. However, PD-resistant grapevine cultivars have been released by UC Davis. Xf-infected grapes can be heavily influenced by water deficit. Preliminary data from a drought-stress experiment in the Summer of 2023 indicated two PD-resistant cultivars perform well under a water deficit. The objective of this study was to evaluate the water dynamics and gas exchange of PD-resistant cultivars during periods of drought. In March 2023, five PD- resistant cultivars and one French-American hybrid were planted in a variety trial at Musser Fruit Research Center in Seneca, SC. The drought-stressed PD-resistant ‘Paseante Noir’ and ‘Errante Noir’ had similar carbon dioxide assimilation to well-watered PD-resistant cultivars. PD-resistant cultivar ‘Ambulo Blanc’ showed the worst leaf water status and lowest carbon dioxide assimilation when stressed. In 2024, physiological measurements, such as sap flow, trunk diameter, gas exchange, and water potential, were taken throughout the growing season. Our results supported previous research that some PD- resistant grapevine cultivars perform well in the field under drought conditions.
Speakers
avatar for Annie Bruno

Annie Bruno

Grad Student, Clemson University
Wednesday September 25, 2024 9:45am - 10:00am HST
Kahili

9:59am HST

Consumer Horticulture and Master Gardeners 1 (CHMG 1)
Wednesday September 25, 2024 9:59am - 11:45am HST
Fruit Classes Teach Invasive Species Management and IPM Practices to Homeowners, Master Gardener Volunteers, and Pesticide Applicators - Kaydie McCormick
Invasive Potential of Ornamental Landscape Plants in Southern Arizona - Michael Chamberland
Education on Water Saving Landscaping Practices Results in Measurable Water Conservation - Tiare Silvasy
Cultivating Connections: Empowering Professionals through NC Farm to School Training Initiative - Liz Driscoll
The gARTening Program: Fostering Community Engagement through Innovative Education - Clarissa Chairez
Welcome Home to Gardening in Tennessee: Reaching New Audiences with New Collaborative Outreach Models - Natalie Bumgarner
Enhancing Backyard Fruiting Cultivation Efficacy Through Florida-Friendly Landscaping™ Techniques for Homeowners - Brittany Council-Morton

Moderator
KM

Kaydie McCormick

University of Florida Institute of Food and Agricultural Sciences
Wednesday September 25, 2024 9:59am - 11:45am HST
South Pacific 2

9:59am HST

Ornamentals/Landscape and Turf 1 (O/LT 1)
Wednesday September 25, 2024 9:59am - 12:00pm HST
BeeGardens Mobile Application Improves Pollinator Plant Knowledge Gain in Landscaping and Gardening Courses - Sandra Wilson
Pesticide Management Decisions Affect Contamination of Nectar in Containerized Ornamental Plant Production - Patrick Wilson
Comparing Pollinator Species Richness and Abundance Between Pycnanthemum Species and Accessions - Kaitlin Swiantek
The Art and Technique of Producing Unique Lagerstroemia Plants - Donglin Zhang
Effects of Different Pruning Regimes on Growth Reallocation and Carbon Storage in Buxus microphylla var. japonica ‘Winter Gem’ - Andrew Loyd
Establishment, Growth, and Physiology of Container-Grown Trees Following Root Remediation at Planting - Bert Cregg
The Effects of Mulch Color and Depth on Soil Temperature and Light Transmission - Damon Abdi
Subterranean Termite Landscape Mulch Consumption Challenge - Edward Bush

Moderator
DZ

Donglin Zhang

University of Georgia
Wednesday September 25, 2024 9:59am - 12:00pm HST
Coral 1

9:59am HST

Postharvest 2 (PH 2)
Wednesday September 25, 2024 9:59am - 12:30pm HST
Postharvest Performance of Tomato Fruit at Shelf-life Conditions in Relation to Fertilization Rate During Plant Production and Fruit Ripening Stage at Harvest - Sotirios Tasioulas
Identification of NAC Transcription Factors Involved in the Ripening and Senescence of Pepper (Capsicum annuum L.) Fruit - Kyeonglim Min
Comparative Analysis of Volatile Organic Compounds of Eight Microgreens in the Brassicaceae Family - Jinhe Bai
Nutritional Quality and Shelf-Life of “Living Lettuce” Through 28 Days of Cold Storage - Marlee Trandel Hayse
Comparing the Postharvest Phytonutrient Content of Red and Green Butterhead Lettuce Cultivars - Marlee Trandel Hayse
Production System Alters Phytonutrient Content of ‘Skyphos’ Butterhead Lettuce - Marlee Trandel Hayse
Improving Postharvest Storage and Late-Season Production of Caladium Tubers in Florida Through Chemical Treatments - Gasselle Cordova
Impact of Storage Environment on Dormancy Progression and Microbiome of Potato Tubers - Munevver Dogramaci
Strawberry Anthocyanins, Extraction, Assessments and Storage - Toktam Taghavi
Isolation of Pathogenic Strain of Trichoderma atroviride from Symptomless, Disease-Free Sweetpotato (Ipomoea batatas L.) Storage Roots - Richard Noel Torres

Moderator
MD

Munevver Dogramaci

United States Department of Agriculture
Wednesday September 25, 2024 9:59am - 12:30pm HST
Nautilus 1

10:00am HST

CHMG 1 - Fruit Classes Teach Invasive Species Management and IPM Practices to Homeowners, Master Gardener Volunteers, and Pesticide Applicators
Wednesday September 25, 2024 10:00am - 10:15am HST
Florida's diverse climate offers ample opportunities for cultivating various fruit crops, especially as traditional citrus faces disease challenges. However, accessible information on alternative fruit crops is limited. In response, a series of online classes was initiated in 2020 to address this gap, coinciding with the need for Continued Education Units (CEUs) for pesticide license holders during COVID-19 lockdowns. The objectives of the class series were threefold: to enhance knowledge of fruit crop cultivation in Central Florida, promote the adoption of Best Management Practices (BMPs) in crop selection and care, and provide CEUs for pesticide license holders in Florida. In its pilot year, three Extension Agents developed a five-week class, expanding to a six-week series in 2021 involving five Agents across three counties. Each session focused on BMPs for landscapes and the cultivation of at least three different fruit crops, including discussions on potential invasive pests as well as alternatives to invasive fruit trees that shouldn’t be planted. The classes were conducted via Zoom and archived on YouTube for wider accessibility. Evaluation of the program included a post-class survey to assess knowledge gain and a three-month follow-up to measure the adoption of practices. Over the course of 2020-2023, the series covered care techniques for 29 different fruit crops. The impact of the classes has been significant. Since 2020, 23 episodes have been produced, attracting a total of 2,015 live viewers. Participants earned a total of 361 CEUs. Survey results indicated a substantial knowledge gain, with 96% (1,480/1,540) of respondents reporting increased understanding of the material. Moreover, 79% (195/248) of respondents adopted at least one new Integrated Pest Management (IPM) strategy after taking the class. According to that same survey 48% (98/202) have altered turf to fruit trees, planting a total of 37,477 square feet with edible plants. In summary, the online class series successfully addressed the demand for information on alternative fruit crops in Florida while providing valuable CEUs for pesticide license holders. Its impact is evidenced by increased knowledge among participants and tangible changes in cultivation practices towards more sustainable and diverse fruit production.
Speakers
KM

Kaydie McCormick

University of Florida Institute of Food and Agricultural Sciences
Co-authors
MP

Morgan Pinkerton

UF/IFAS Extension Seminole County
TS

Tiare Silvasy

UF/IFAS Extension Hillsborough County
NA
TM

Tina McIntyre

UF/IFAS Extension Seminole County
NA
WL

William Lester

UF/IFAS Extension Hernando County
Wednesday September 25, 2024 10:00am - 10:15am HST
South Pacific 2

10:00am HST

NUTS 1 - Performance of Five Early-harvest Pecan Cultivars in South Georgia
Wednesday September 25, 2024 10:00am - 10:15am HST
Five pecan (Carya illinoinensis) cultivars were evaluated over 15 years in a trial at Tifton, GA, USA. Trialed cultivars included the standard early cultivar Pawnee, and the more recent releases Byrd, Morrill, Lakota, and Treadwell. Actual yield were measured for each tree each year and a 50-nut sample was taken to determine nut quality. Trees were evaluated for leaf and nut scab infection (Venturia effusa) and black aphid (Melanocallis caryaefoliae) damage. ‘Pawnee’ yielded significantly less than all the newer cultivars which had similar cumulative yields. However, ‘Byrd’, ‘Lakota’, and ‘Treadwell’ had significantly more yield alternation than ‘Pawnee’ and ‘Morrill’, with reduction of nut quality in the “ON” years. ‘Pawnee’ was the earliest cultivar and produced excellent quality nuts, but yields were mediocre. ‘Lakota’ had excellent scab resistance, but overcropped resulting in inferior quality, and should only be grown in orchards were crop loads are controlled by hedging or tree shaking. ‘Byrd’ and ‘Treadwell’ are very scab susceptible and also need crop load control, making them poorly suited for south Georgia. ‘Morrill’ had consistent cropping and excellent nut quality but is also very scab susceptible and should only be grown with excellent disease management practices.
Speakers
PC

Patrick Conner

University of Georgia
Wednesday September 25, 2024 10:00am - 10:15am HST
Lehua Suite

10:00am HST

O/LT 1 - BeeGardens Mobile Application Improves Pollinator Plant Knowledge Gain in Landscaping and Gardening Courses
Wednesday September 25, 2024 10:00am - 10:15am HST
Florida is home to over 300 species of native wild bees, some in critical decline. To encourage gardeners to plant bee friendly species that support bee pollinators year-round, an online application called BeeGardens was built using a shared library of code and a relational database management system. The application, accessible by a mobile device or computer, enables users to quickly access over 85 bee-friendly plants that attract 12 primary bee groups; and provides tips for incorporating these into different landscape designs (https://ffl.ifas.ufl.edu/bees). The functionality and usefulness of the app was evaluated by students enrolled in two courses at the University of Florida: Florida Native Landscaping and Annual and Perennial Gardening, taught in different semesters. Before and after the semester, students were asked to report their abilities to 1) identify bee-friendly plants, 2) identify bee pollinators, and 3) design a bee-friendly garden, using a Likert scale with responses ranging from 1 (strongly disagree) to 5 (strongly agree). Means of pre- and post-test responses showed a significant perceived knowledge gain upon using the BeeGardens online application in both courses. This data was consistent with pre- and post-tested means where students were asked to identify three major pollinator plants and three major pollinators using multiple choice response options. Test scores increased by 26.3% and 37.9% in Annual and Perennial Gardening and Florida Native Landscaping, respectively. The majority of students (95.0%) agreed or strongly agreed this learning tool was organized, easy to navigate, and would use it in the future. Since its inception in March 2021, this web application has been accessed by over 26,554 new users from across Florida and beyond.
Speakers
avatar for Sandra Wilson

Sandra Wilson

Professor, University of Florida
Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral... Read More →
Co-authors
HK

Heather Kalaman

UF IFAS Extension Orange County
RM

Rachel Mallinger

University of Florida
NA
Wednesday September 25, 2024 10:00am - 10:15am HST
Coral 1

10:00am HST

PH 2 - Postharvest Performance of Tomato Fruit at Shelf-life Conditions in Relation to Fertilization Rate During Plant Producti
Wednesday September 25, 2024 10:00am - 10:15am HST
This study investigates how the ripening stage at harvest and fertilization rate impact tomato fruit quality. Tomato plants (cv. HM1823) were grown during the Fall 2023 season under four levels of fertilization (75%, 100%, 125%, and 150% of the recommended UF/IFAS rate, which is 200 lb/A nitrogen and potassium). Fruit were harvested at four distinct ripening stages: mature green (MG), turning (T), pink (P), and red (R), as assessed visually and stored at 25°C. Color, firmness, soluble solids content (SSC), pH, and titratable acidity (TA) were measured every 4 days until 12 or 16 days (for MG fruit). According to the analysis of variance, all factors (fertilization rate-FR, ripening stage at harvest- RS and shelf life period- SL), as well as the interaction RSSL significantly (P
Speakers
ST

Sotirios Tasioulas

SWFREC - University of Florida/IFAS
Co-authors
JW

Jessie Watson

SWFREC - University of Florida/IFAS
NA
PT

Pavlos Tsouvaltzis

Southwest Florida Research and Education Center, University of Florida
NA
Wednesday September 25, 2024 10:00am - 10:15am HST
Nautilus 1

10:00am HST

VSF 2 - Diversity and Abundance of Bees Visiting Grape Flowers in Wisconsin Vineyards
Wednesday September 25, 2024 10:00am - 10:15am HST
Bees play an essential role in plant pollination and the ecosystem services they provide to increase the quantity and quality of many agricultural crops. Many food crops are either dependent on, or benefit from, bee pollination, yet bees have experienced population declines due to a combination of factors including pesticide exposure, susceptibility to pathogens and parasites, habitat loss through land use intensification, and lack of suitable resources. Most studies on pollinator conservation and pollination services focus on pollinator-dependent crops and fail to address the role self- and wind-pollinated plants, such as grapes, play in maintaining or threatening pollinators. In vineyards, bees are often overlooked, as they are not required for the pollination of grape. This study aimed to survey the bees visiting grape flowers of cold climate grapes by recording the abundance and diversity of bees. Observations were conducted at six commercial vineyards in South Central Wisconsin during grape bloom, late May to mid-June in 2022. At each vineyard, vines of mixed cold-climate grape varieties were observed between 10:00 and 17:00 hrs on six separate days. Timed observations (5 min per vine) of bees visiting grape inflorescences were conducted at ten randomly selected grape plants per plot per day. In addition, each day, one 10 min wandering transect was walked along two adjacent rows of grape vines and all bees observed visiting grape inflorescences were recorded. To prevent destructive sampling, bees were identified in the field to species when known or assigned to one of 14 pre-determined morphospecies representing 24 likely genera. Timed plant observations showed a total of 1,059 floral visitations, with an average of 0.31 /- 0.16 bees per minute of sampling. During the wandering transects, a total of 417 floral visitations were observed, with 1.44 /- 0.43 bee visits per minute of sampling. This research underscores the need for reduced pesticide inputs, particularly around bloom time, to protect the diversity and abundance of bees visiting grape inflorescences.
Speakers
CG

Christelle Guedot

University of Wisconsin - Madison
Co-authors
ML

Mitchell Lannan

University of Wisconsin - Madison
NA
Wednesday September 25, 2024 10:00am - 10:15am HST
Kahili

10:00am HST

Ornamentals Collaboration Session
Wednesday September 25, 2024 10:00am - 11:00am HST
A forum for discussion of potential collaborations with regards to ornamentals – i.e. floriculture, nursery crops, breeding, turf, ornamentals industry, botanic gardens, landscape industry, orchids, etc.
Wednesday September 25, 2024 10:00am - 11:00am HST
Coral 4

10:00am HST

Organic Horticulture Interest Group - Discussion on the regional activities of USDA-AMS Transition to Organic Partnership Program (TOPP)
Wednesday September 25, 2024 10:00am - 11:00am HST
Discussion on the regional activities of USDA-AMS Transition to Organic Partnership Program (TOPP)
Speakers
avatar for Christine Coker

Christine Coker

Professor or Urban Horticulture, Mississippi State University
Wednesday September 25, 2024 10:00am - 11:00am HST
Sea Pearl 4

10:14am HST

Herbs, Spices, and Medicinal Plants 1 (HSMP 1)
Wednesday September 25, 2024 10:14am - 11:45am HST
Saffron (Crocus sativus) Production in North Central New Mexico - Saeid Zehtab Salmasi
Experiences Cropping Wasabi in Inland Oregon - Clint Taylor
Double-season production of hops (Humulus lupulus L.) with photoperiod manipulation in a subtropical climate - Shinsuke Agehara
Brewing Conditions and UV treatment affect Shelf Life of Cold-brew US-grown Tea - Yan Chen
Withering Duration and Drying Temperature Significantly Affect Postharvest Quality of Kratom (Mitragyna speciosa) - Mengzi Zhang
Consumer preference of saffron uses in baked goods and dishes - Hideka Kobayashi
Moderator
SZ

Saeid Zehtab Salmasi

Associate Professor and Research Director, New Mexico State University
Research Director of the Sustainable Agriculture Science Center of New Mexico State University in Alcalde
Wednesday September 25, 2024 10:14am - 11:45am HST
South Pacific 1

10:14am HST

Water Utilization and Management 1 (WUM 1)
Wednesday September 25, 2024 10:14am - 11:45am HST
Developing Irrigation Tools and Information for Effective Irrigation Management of California’s Avocado Orchards - Ali Montazar
Comparative Assessment of Satellite-Derived Crop Evapotranspiration and Estimated Evapotranspiration in Almond and Walnut Orchards for Precision Irrigation Management - Abdelmoneim Mohamed
Physiological Thresholds Provide Targets for Climate-Resilient Irrigation Management in Hazelnut - Steven Bristow
Determination of Crop Coefficient and its Inter-annual Variability in Pecan Orchard in Georgia - Kriti Poudel
Assessing Water Status in Citrus Plants Using Thermal Imaging in Greenhouses - Gustavo Haddad Souza Vieira
The Impact of Irrigation Rates Based on Crop Water Requirement on Tree Growth and Water Relations in Commercial Citrus Groves - Alisheikh Atta
Moderator
AM

Ali Montazar

University Of California Cooperative Extension
Wednesday September 25, 2024 10:14am - 11:45am HST
South Pacific 4

10:15am HST

CHMG 1 - Invasive Potential of Ornamental Landscape Plants in Southern Arizona
Wednesday September 25, 2024 10:15am - 10:30am HST
Plants introduced through ornamental horticulture have contributed to exotic species invasions around the world. Fifteen landscape plants commonly used in horticulture in southern Arizona have been evaluated using the Plant Risk Evaluator (PRE) tool developed by PlantRight and Cal-IPC. The evaluations have recognized eight of these species as presenting high potential risk of escaping cultivation and becoming invasive in Arizona. The process of evaluating ornamentals has fostered communication and collaboration between invasive species managers and Extension horticulture agents, who previously had little interaction. The findings have been communicated through several articles on invasive species in the trade magazine, Southwest Horticulture. This information has contributed to two cultivated species (Searsia lancea and Ulmus pumila) and the entire genus Tamarix being newly added to the Arizona State Noxious Weed List. Arizona Master Gardeners have been educated on invasive plant issues to foster outreach to the public and to aid their planting choices.
Speakers
MC

Michael Chamberland

University of Arizona
Wednesday September 25, 2024 10:15am - 10:30am HST
South Pacific 2

10:15am HST

HSMP 1 - Saffron (Crocus sativus) Production in North Central New Mexico
Wednesday September 25, 2024 10:15am - 10:30am HST
Saffron (Crocus sativus L.) holds a high economic value as the world's most expensive spice. It plays a crucial role in many small farm economies in countries such as Iran, India, Afghanistan, Greece, Morocco, Spain, and Italy. In this project the effects of three different corm size (10 ,9 , and 8 ) on saffron stigma’s yield were studied in hoop house and open field production systems in a randomized complete block design with three replications at Certified Organic Farm of the Sustainable Agriculture Science Center of New Mexico State University in Alcalde located in north central New Mexico. Saffron corms were planted 6 to 8 inches in depth and 6 inches apart on September 19, 2023. The saffron flowers were harvested from October 18th until November 6th, 2023, in different treatments. Flowering started earlier and the flowering period was longer in plots planted with bigger corms. Saffron flowers picked up in the morning and then the stigmas were separated and dehydrated at 100 °C for ten minutes. The first-year results showed that the highest number of flowers were obtained from 10 corm size plots. The highest yield of dehydrated stigmas was also harvested from 10 corm size in high tunnel production system with 3.43 Kg/ha (3.06 lbs./acre). The bigger corms of saffron produced significantly higher stigma yield than smaller ones; 2.84 kg/ha (2.53 lbs./acre) for 10 corms vs 0.89 kg/ha (0.79 lbs./acre) for 8 corms, however, the difference between saffron yield in high tunnel and open field production systems was not significant. In summary the outcome of this research shows that saffron can be produced successfully even in open field production system in northern New Mexico and using bigger corms for planting may produce higher saffron in the first year, although the evaluation of winter hardiness and the following years performance will be necessary.
Speakers
SZ

Saeid Zehtab Salmasi

Associate Professor and Research Director, New Mexico State University
Research Director of the Sustainable Agriculture Science Center of New Mexico State University in Alcalde
Co-authors
RH

Robert Heyduck

New Mexico State University
NA
Wednesday September 25, 2024 10:15am - 10:30am HST
South Pacific 1

10:15am HST

NUTS 1 - Enhancing Pecan Tree Resilience Against Spring Freeze Events: Insights from Secondary Bud Dynamics and Carbohydrate Analysis
Wednesday September 25, 2024 10:15am - 10:30am HST
Pecan growers face significant challenges in protecting their crops from the spring freezes that devastate yields. Conventional freeze protection methods are impractical for the large, tall trees. This study investigated the dynamics of the secondary bud break in pecan trees, a mechanism that ensures yield when primary buds are damaged. In three pecan cultivars ('Pawnee,' 'Kanza,' and 'Maramec') we characterized the sprouting potential of secondary buds after the primary buds were cold damaged. Primary bud shoots were collected at three different bud growth stages: outer bud scale shed stage, inner bud scale shed stage, and early bloom stage. The shoot samples held at 6°C to terminate primary buds’ growth. The cold treated shoots were then held in growth chambers set to mimic spring humidity, temperature, and light conditions. The percentage of branches with secondary bud break was recorded. The carbohydrate levels (sugar and starch) were measured in the apical shoots treated at the outer bud scale shed stage. The results showed variation among cultivars in the number of shoots with secondary buds and the stage at which primary buds were terminated. The ‘Kanza’ and ‘Pawnee’ cultivars produced more secondary buds when the primary buds were cold damaged in the outer bud scale shed stage. The ‘Maramec’ cultivar produced more secondary buds when the primary buds were cold damaged in the inner bud scale shed stage. The A carbohydrate analysis of the three cultivars demonstrated a correlation between successful secondary bud break and elevated carbohydrate levels in the one-year-old shoots. Cultivars with higher secondary bud break rates, 'Kanza' and 'Pawnee', had higher carbohydrate levels than 'Maramec.' These findings suggest that higher carbohydrate levels in one-year-old shoots facilitate successful secondary bud break following spring freeze damage to primary buds. This research suggests developing production practices to improve tree carbohydrate levels in the late summer and fall could potentially protect pecan production from spring freeze damage.
Speakers
LZ

Lu Zhang

Oklahoma State University
Co-authors
AK

Amandeep Kaur

Oklahoma State University
NA
JM

Justin Moss

Oklahoma State University
NA
LF

Louise Ferguson

University of California, Davis
NA
NM

Niels Maness

Oklahoma State University
NA
YS

Yanwei Sun

Oklahoma State University
NA
Wednesday September 25, 2024 10:15am - 10:30am HST
Lehua Suite

10:15am HST

O/LT 1 - Pesticide Management Decisions Affect Contamination of Nectar in Containerized Ornamental Plant Production
Wednesday September 25, 2024 10:15am - 10:30am HST
Declines in pollinator populations have gained much attention over the last decade. Exposures to pesticides are one potential contributor to these declines. Given that the ornamental plant production industry produces crops that are attractive to pollinators and that pesticide use is often integral to ensuring plants are pest-free, attention is needed to assess and possibly reduce contamination of flower nectar and pollen before plants go to market. Three major factors associated with pesticide management practices that may influence contamination of floral resources are: application method, application rate, and application timing relative to flowering. Using the systemic insecticide thiamethoxam as a model pesticide and Salvia x ‘Indigo Spires’ (Salvia longispicata x S. farinacea) as a model species, this study investigated the influence of each of these factors on contamination of nectar. Plants were treated by spray and drench methods, at low and high rates according to the pesticide label, and before flower buds formed or close to the time of floret opening. Nectar samples were collected using microcapillary tubes when all plants were uniformly flowering and thiamethoxam concentrations were analyzed by LC-MS/MS. Concentrations of thiamethoxam in nectar were highest in drench applications, regardless of application timing and rate, and exceeded published LC50s for native bees and/or honeybees. Thiamethoxam concentrations were much lower in the spray-applied treatments, but they still exceeded published LC50s for native bees and/or honeybees except for the spray treatment applied before blooming at the low rate. These results provide insight into how some pesticide management practices influence contamination of floral resources and indicate a need for developing best management practices focused on limiting thiamethoxam exposures once plants go to market. Additional studies are underway to evaluate other plant species and systemic insecticides to address gaps in knowledge.
Speakers
PW

Patrick Wilson

University of Florida
NA
Co-authors
MC

Mia Cabrera

university of florida
NA
SW

sandra wilson

University of Florida
Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral... Read More →
VR

Vanesa Rostan

university of florida
NA
Wednesday September 25, 2024 10:15am - 10:30am HST
Coral 1

10:15am HST

PH 2 - Identification of NAC Transcription Factors Involved in the Ripening and Senescence of Pepper (Capsicum annuum L.) Fruit
Wednesday September 25, 2024 10:15am - 10:30am HST
Pepper (Capsicum annuum L.) as a non-climacteric fruit is usually harvested at either mature green or ripe stage, and fruit quality including texture, color, and nutritive values is different according to the fruit developmental stages. Understanding molecular mechanisms of fruit ripening and senescence processes is crucial to control the fruit quality and reduce the postharvest loss. This study was aimed to identify NAC transcription factors (TFs) involved in the ripening and senescence of pepper fruit by analyzing gene expressions and protein-protein interactions. To identify NAC genes related to the ripening, transcript levels of total 104 NAC TFs were investigated using publicly available transcriptome data. Among them, transcript levels of 8 genes significantly increased during the ripening and senescence. Their phylogenetic analysis also showed that they are closely associated with NAC TFs which play a role in ripening or senescence in other crop species. Among them, 4 genes showing abundant transcript levels at the ripening stage were selected, including CaNAC14, 45, 84, and 92, to further investigate their roles. In pepper (C. annuum var. ‘Gyeonggiyangpyeiong’) fruit, their expressions clearly increased during the ripening or induced by exogenous ABA, the major phytohormone regulating non-climacteric fruit ripening. To reveal a relationship between the CaNACs and ABA signaling, protein-protein interactions between the CaNACs and ABA receptors were analyzed through yeast- two-hybrid and bimolecular-fluorescence complementation assays. Among them, CaNAC92 and CaPYL12, the ABA receptor, interacted each other in a nucleus with an ABA-dependent manner. This result indicated that their interaction may affect the ABA signaling or the transcriptional regulation during the ripening. We identified CaNAC TFs involved in the pepper fruit ripening and suggested CaNAC92 as a putative molecule functioning in the ripening. These findings will provide genetic information to control the ripening and to improve pepper fruit quality.
Speakers
KM

Kyeonglim Min

Student, Seoul National University
Co-authors
EJ

Eun Jin Lee

Seoul National University
Wednesday September 25, 2024 10:15am - 10:30am HST
Nautilus 1

10:15am HST

VSF 2 - The Grape Health Index: Validation of a New Methodology for Quantifying Wine Grape Spoilage by Means of FT-MIR Spectrosc
Wednesday September 25, 2024 10:15am - 10:30am HST
For wineries processing hand harvested grapes, a visual inspection of microbial spoilage is expedient and cost effective. However, due to the increasing adoption of machine harvesters, which frequently rupture berry skins making visual inspection less precise, and the high degree of error of visual inspections between individuals, a quantitative approach to assess spoilage is needed. Fourier Transform Mid-Infrared Spectroscopy (FT-MIR), combined with multivariate analysis, is being investigated as an approach to predict grape health as a sample that can be analyzed in less than one minute. Calibration data was obtained from grape samples of Chardonnay, Riesling, Petite Sirah, and Zinfandel, which were sorted into fractions of 0, 5, 10, 15, and 20% microbially impacted clusters in healthy grape material, and analyzed using the spectrophotometer. The spectral data was analyzed using the Partial Least Squares (PLS) regression. Predicting factors included volatile acidity (VA), gluconic acid, ethanol, lactic acid, glucose-fructose content, Brix, titratable acidity, tartaric acid, malic acid, pH, alpha amino nitrogen, ammonia, and yeast assimilable nitrogen (YAN). A model was selected which optimized for a high coefficient of determination (R2) and a low root mean squared error (RMSE). Additional selection criteria included the extent to which predicting factors have been observed to correlate with microbial spoilage in other studies. The model selected had a R2 of 0.620 and a RMSE of 4.596, making it suitable for identifying grapes marked by spoilage. The output of the model was converted to Grape Health Index (GHI) Scores for better usability by operators at the test stand. The GHI was implemented at the test stands of two large-scale wineries during the 2022 and 2023 seasons. Additional wineries will be added in 2024. The testing of the impact of microbial spoilage on wine aging is currently underway. Wines made in 2018, 2019 and 2020 are evaluated for color degradation and browning, anthocyanins, tannins, pigments, and acetaldehyde. The results will be compared with the original harvest results for comparative analysis concluding the project.
Speakers
SV

Sonet Van Zyl

Fresno State
Co-authors
SS

Stephan Sommer

University of Missouri
NA
SC

Steven Craig Ebersole

Foley Family Wines
NA
Wednesday September 25, 2024 10:15am - 10:30am HST
Kahili

10:15am HST

WUM 1 - Developing Irrigation Tools and Information for Effective Irrigation Management of California’s Avocado Orchards
Wednesday September 25, 2024 10:15am - 10:30am HST
In California, avocado is primarily grown in Southern and Central parts of the state, typically in regions tempered by coastal climates and fine or course sandy loam soils. These regions face uncertain water supplies, mandatory reductions of water use, and the rising cost of water, while efficient use of irrigation water is one of the highest conservation priorities. Moreover, due to increasing salinity in water sources, effective irrigation is more critical to ensure optimal yield and high-quality avocado fruits. A two-year study was conducted in 12 mature avocado sites in California. Extensive field measurements and surveys were conducted to better understand the current water management practices, to acquire and develop relevant information on crop water use (ET) and crop coefficients, and to assess the performance of satellite-based OpenET tool for irrigation management in avocados. Surface renewal and eddy covariance equipment was used to measure actual evapotranspiration (ETa) in each site. The results illustrated considerable variability in avocado crop water consumption both spatially and temporally. The crop coefficients curves were developed for each site. Across the avocado research sites, the average seasonal crop coefficient values varied from 0.6 to 0.76. The findings demonstrated that canopy features, soil types and conditions, pruning practices, soil surface cover, and row orientations need to be considered to perform effective water management in avocado orchards. Ground shading percentage and row orientations provide a good estimation of canopy size/volume and the amount of light that it can intercept are likely the most important drivers influence crop water needs. The RMSE of the measured ETa from eddy covariance equipment and estimated ETa from Ensemble OpenET varied from 0.53 to 1.37 mm d-1. The preliminarily findings indicated that the Ensemble OpenET estimates ETa relatively well in some sites and could be an effective irrigation management tool in the future for avocado orchards, however more evaluations are required.
Speakers
AM

Ali Montazar

University Of California Cooperative Extension
Wednesday September 25, 2024 10:15am - 10:30am HST
South Pacific 4

10:15am HST

Workshop: Breeding for Post-harvest Shelf Life in Vegetable Crops
Wednesday September 25, 2024 10:15am - 12:15pm HST
Improved postharvest storage is a major target for vegetable-crop production. Nutritional contents and flavor are traits highly affected from harvesting to final consumption. Several reports have demonstrated that these traits are strong driving factors impacting consumers’ decisions and preferences when purchasing food. Therefore, these are economically important traits related to strong commercialization potential and improved market value. Assessing the potential variation in post-harvest shelf life among vegetable crops will be critical to identify parental lines that can be used in breeding programs to improve these traits and their effect on the quality of produce. Additionally, investigating the genetic mechanisms underlying post-harvest shelf life in horticultural crops is critical. This will result in the development of molecular breeding tools associated with improving shelf life, which will accelerate breeding. This interest group seeks to provide case studies from experts worldwide who have worked on breeding for nutritional contents, flavor, and post-harvest shelf life in vegetables.

Coordinator(s)
  • Carlos Avila, Texas A&M AgriLife Research, Weslaco, TX, United States
Moderator(s)
  • Dennis Nicuh Lozada, New Mexico State University, Plant and Environmental Sciences, Las Cruces, NM, United States
  • Devi Kandel, Langston University, United States
Speaker/Participant(s)
  • Carmit Ziv, Institute of Postharvest and Food Science, ARO, Volcani Institute, Israel
    Breeding for improved postharvest quality of peppers during cold storage (15 mins)
    Summary: Dr. Ziv's research program studies postharvest disease control of fruity vegetables by developing environment-friendly treatments to control postharvest fungal rot, understanding resistance mechanisms of phytopathogenic fungi to cold storage, uncovering the role of lipids in determining the interactions between fruits and pathogenic fungi during storage.
  • Carlos Avila, Texas A&M AgriLife Research, Weslaco, TX, United States
    Lack of locule gel increases post-harvest shelf-life and quality in tomato (15 mins)
    Summary: Dr. Avila's research program is focused on the development of tomato and spinach cultivars adapted to Texas conditions. Research work includes the characterization of plant a/biotic stress and vegetable quality trait regulation using molecular, physiological, and biochemical approaches to develop applied strategies to improve breeding efficiency and ultimately crop resistance and quality. Current efforts include the development of firm long shelf-life tomato cultivars with improved flavor and nutritional content.
  • Bhimu Patil, Texas A&M University, Vegetable and Fruit Improvement Center, College Station, Texas, United States
    Post-harvest shelf life and nutritional quality in horticultural crops (15 mins)
    Summary: Dr. Patil has been actively involved in both research and educational activities related to global level ‘Foods for Health’. His research, in collaboration with trans-disciplinary scientists, related to bioactive-derived assays led to isolation and characterization of certain bioactive compounds in citrus and turmeric and other vegetables. His research is also focused on pre and postharvest effects on bioactive compounds in citrus, onion and recently his work is focused on other vegetables and fruits.
  • Alexander Goldshmidt, Institute of Plant Sciences, ARO, Volcani Institute, Israel
    Exploring the Role of CLASS-II KNOX mediated Ripening Pathways for the Discovery of Novel Genetic Approaches to Extend Fruit Shelf Life (15 mins)
    Summary: Dr. Goldshmidt research is focused on investigation of the genetic factors and networks controlling development of the pericarp tissues in fruits of Solanaceae crops tomato and pepper. His lab seek to use their research to develop novel genetic solutions and tools to extend fruit's shelf life and improve its consumer attractiveness and nutritional values.
  • Barbara Blanco Ulate, UC Davis, United States
    Control of fruit ripening, improvement of fruit quality, and fruit-pathogen interactions. (15 mins)
    Summary: Dr. Blanco-Ulate's research program integrate systems biology approaches with biochemical and physiological analyses to study fruit development and quality traits, and to establish a novel framework for the early detection and efficient management of fruit diseases.





Wednesday September 25, 2024 10:15am - 12:15pm HST
Coral 2

10:29am HST

Nursery Crops/Root Growth and Rhizosphere Dynamics (NUR/RHIZ)
Wednesday September 25, 2024 10:29am - 11:10am HST
A Snapshot of Nursery Container Substrate Prices in Tennessee - Amy Fulcher
Suppression of Stem Elongation of UV-B Treatment Timing and Intensity on Tomato Scion and Rootstock in Plant Factory with Artificial Lighting - Dongcheol Jjang
Effects of Nitrogen on the Nodulation of Ceanothus velutinus - PRAKRITI NEPAL
Evaluating the Effects of Varying Container Height and Volumes on Southern Highbush Blueberry Production - Brandan Shur
Moderator
PN

PRAKRITI NEPAL

Utah State Univeristy
Wednesday September 25, 2024 10:29am - 11:10am HST
South Pacific 3

10:30am HST

NUR/RHIZ - A Snapshot of Nursery Container Substrate Prices in Tennessee
Wednesday September 25, 2024 10:30am - 10:40am HST
In container nursery production, the potting substrate serves as the foundation of the crop, providing essential nutrients, aeration, and moisture retention. A well-chosen substrate is crucial for optimizing plant health and growth, and ultimately influences a nursery’s economic viability since substrate is estimated to be 13% of the total variable costs of 3-gallon production. Our objective is to determine the cost of common potting substrate components. The study goal is to identify opportunities for nursery producers to reduce costs and increase profits by optimizing their substrate components. Email surveys supplemented by interviews were used to collect data from six Tennessee container nursery producers. All growers were within a 117-mile radius of McMinnville, Tennessee, and provided the prices they paid in the last 12 months for the primary components of their potting substrate. Delivery fees and fuel surcharges were not considered in the cost when these expenses were itemized. However, one producer’s prices included delivery expenses. Participating nursery producers self-identified as having 100 (66.7%) acres in container production. Growers in this case study paid an average of $19.07 (SD=$5.53) per yard3 for pine bark; however, the prices ranged from $14.53 to $29.00 per yard3. In general, smaller producers paid more for pine bark. Sand ranged from $40.50 to $49.95 per yd3. Nursery producers paid $1.12 to 1.32 per pound for controlled release fertilizer (CRF), an input estimated at 5% of total variable costs. Therefore, some growers paid 18% more for CRF than others. Growers paid from $0.01 to $0.11 per pound for lime. Tennessee nursery producers were paying on average $66.79 per cubic yard for wood fiber-based substrate and vermicompost, 250% more than the average cost of pine bark but just 46% of the market price for peat. These preliminary data show 1) individual nurseries pay a range of prices for the same potting substrate components, and 2) the relatively high cost of peat replacements, i.e., wood fiber and vermicompost. The data highlight the range of prices being paid for CRF and its relative expense, underscoring the opportunity for growers to reduce costs by optimizing their use and placement of CRF. Additional research is needed to more broadly sample nurseries for these data and determine the influence of nursery size on substrate component costs. cparwutcakwt8uvpamtb
Speakers
AF

Amy Fulcher

University of Tennessee
Co-authors
AR

Alicia Rihn

University of Tennessee
JO

James Owen

USDA-ARS
Jim Owens is a USDA-ARS Research Horticulturist located at the Application Technology Research Unit in Wooster, OH. Jim received his B.Sc. in Plant and Soil Science at the University of Kentucky, his M.Sc. in Environmental Science at the University of Rhode Island, and Ph.D. at North... Read More →
WH

Walker Harrell

University of Tennessee
NA
Wednesday September 25, 2024 10:30am - 10:40am HST
South Pacific 3

10:30am HST

CHMG 1 - Education on Water Saving Landscaping Practices Results in Measurable Water Conservation
Wednesday September 25, 2024 10:30am - 10:45am HST
Florida is facing critical water scarcity due to population growth. The home landscape is an opportune setting to make changes in practices to conserve water. Extension programs on water conservation in the landscape can provide residents with the information they need to adopt new practices to conserve water. In 2021-2023, UF/IFAS Extension residential horticulture programs in Central Florida, educated 6,474 residents about sustainable landscape practices. Based on client self-reported follow-up surveys (n=342), the annual water savings due to adoption of best landscaping practices was approximately 11.6 million gallons. It saved homeowners $49,977 in utility bills (based on regional value of $4.30 per 1,000 gallons). The most adopted practices included calibrating sprinkler systems to deliver ½ inch to ¾ inch of water instead of 1 inch, reducing irrigation frequency during summer, and reducing irrigation frequency during winter. Adoption is lower for water conservation practices that require installing soil moisture sensors and converting or installing irrigation spray heads. Participants reported (n=342): 35% eliminated irrigation or converted to low volume irrigation, 46% reduced irrigation from 3 to 2 days per week, 45% reduced irrigation frequency in winter, 46% reduced irrigation frequency in summer, 25% using a working rain shutoff device, 37% calibrated irrigation to ½” or ¾” rather than 1” or more. Impacts of changes in household water use multiply when life cycle assessment of a water supply system is considered. The reduction of 11.6 million gallons of residential water use resulted in saving 40,022 kWh of energy and $30,162 in treating and delivering water to the end users, reducing 28 metric tons of carbon dioxide equivalent of greenhouse gas emissions, deferring the need for $98,734 investment in alternative water supply infrastructure, and potentially reducing stormwater runoff and avoiding water quality deterioration. The impacts of these water conservation efforts are even greater than the values represented here based on total program attendance. This shows the efforts of extension agents educational programs resulted in measurable water savings to help Florida households conserve water.
Speakers
TS

Tiare Silvasy

University of Florida
Wednesday September 25, 2024 10:30am - 10:45am HST
South Pacific 2

10:30am HST

HSMP 1 - Experiences Cropping Wasabi in Inland Oregon
Wednesday September 25, 2024 10:30am - 10:45am HST
Wasabi (Eutrema japonicum) is a high-value and notoriously difficult crop traditionally cultivated in East Asia. There has been some limited commercial cultivation of the crop in the Pacific Northwest, including in the coastal mountains of Oregon. This presentation shares insights into the challenges and approaches to inland wasabi farming, focusing on environmental conditions, potential growing systems, and media types. Key points include: 1. Environmental Conditions: Wasabi has a narrow range of light, temperature, and water requirements and is prone to a myriad of fungal and bacterial diseases. Knowing this narrow range is essential to the practicality of commercial wasabi production. Balancing the ideal environmental factors for wasabi without creating disease outbreaks is a primary challenge in wasabi production. 2. Growing System
Speakers
avatar for Clint Taylor

Clint Taylor

Oregon State University - NWREC
Co-authors
CB

Chip Bubl

Oregon State University
NA
CO

Cynthia Ocamb

Oregon State University
NA
DM

Dalyn McCauley

Oregon State University
LN

Lloyd Nackley

Oregon State University
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
Wednesday September 25, 2024 10:30am - 10:45am HST
South Pacific 1

10:30am HST

NUTS 1 - Biochar in Pecan Orchards: Unraveling Water Stress Dynamics for Sustainable Irrigation Management
Wednesday September 25, 2024 10:30am - 10:45am HST
Pecan orchards in the southwestern United States face significant challenges due to persistent drought conditions that adversely affect yield and nut quality. Pecans are recognized as the most water-intensive crop in the region, and therefore require innovative strategies to optimize the available irrigation water. This study explores the use of pecan wood-derived biochar as a soil amendment to enhance the soil water-holding capacity and alleviate water stress in pecan orchards. We conducted field experiments during the summer of 2023 in a flood-irrigated pecan orchard located in the Mesilla Valley, New Mexico, USA. We accounted for the irrigation gradient in a flood-irrigated orchard by using a randomized complete block design with four blocks, each containing three equidistant trees from the irrigation valves. The trees within each block were randomly assigned to one of three biochar application rates: 0 kg/ha (treated area), 6300 kg/ha, and 12600 kg/ha. The treated area was situated within the herbicide strip, spanning 9.14 m in length – centered on the tree – with 1.22 m on either side of the tree. To assess tree water status, two leaf samples from the lower shaded canopy were covered in aluminum foil bags for a minimum of 15 minutes before mid-day stem water potential was measured. Mid-day stem water potential was measured throughout the growing season near the end of each irrigation dry-down cycle. For each tree, we calculated the average mid-day stem water potential and then performed an ANOVA to compare the averages across the treatment groups. In the five months after biochar application, there were no significant differences in tree water status across the treatment groups. This highlights the need for more research to study the interactions among soil moisture content, biochar amendment applications, and pecan tree mid-day stem water potential. This study contributes to the ongoing discourse that calls for enhancing crop water use efficiency in arid regions by providing a foundation for future studies that seek to use biochar as a sustainable agricultural practice in pecan orchards.
Speakers
JM

Jamin Miller

New Mexico State University
Co-authors
AF

Alexander Fernald

New Mexico State University
NA
CV

Ciro Velasco-Cruz

New Mexico State University
NA
DD

David Dubois

New Mexico State University
NA
JI

John Idowu

New Mexico State University
NA
RH

Richard Heerema

New Mexico State University
NA
Wednesday September 25, 2024 10:30am - 10:45am HST
Lehua Suite

10:30am HST

O/LT 1 - Comparing Pollinator Species Richness and Abundance Between Pycnanthemum Species and Accessions
Wednesday September 25, 2024 10:30am - 10:45am HST
Pollinators play a crucial role in the ecosystem, human health, and the economy. However, despite the significance of pollinators, their populations are declining globally. Pycnanthemum is a marketable pollinator-attractive plant that could supplement pollinator resources in the landscape. Breeders would benefit from a comparison of the pollinator attractiveness between Pycnanthemum species and accessions. Cultivating Pycnanthemum should focus on aesthetic traits and maximizing pollinator abundance and species richness. Pollinator visitation was compared among three species and five accessions of Pycnanthemum (P. flexuosum (F), P. virginianum (V), and three accessions of P. tenuifolium (T1-T3)) using observations and capture. Lepidoptera, honey bees (Apis mellifera), Diptera, carpenter bees (Xylocopa spp.), small bees, and bumble bees (Bombus spp.) were observed most abundantly on Plant F. Plant V attracted the highest number of pollinators overall, with Apis mellifera (honey bees) accounting for more than half of the pollinator visitation. Xylocopa spp. (carpenter bees) and honey bees did not have a significant preference between the species. Plants F, T2, T3, and V attracted the greatest abundance of Diptera (flies). Wasps were most attracted to Plants T3 and V, while Bombus spp. (bumble bees) was observed most often on Plants F and V. Plant F attracted the highest number of Lepidoptera (butterflies and moths) and small bees. The species richness of pollinators did not significantly differ across Pycnanthemum species, with at least 24 to 29 different pollinator species visiting each plant. A range of factors, including olfactory cues, the morphology of plants, and accessibility of resources, may have affected pollinator preferences. Determining which Pycnanthemum species attracted an abundance and diversity of pollinators provides breeders a foundation for cultivation and conservation expectations.
Speakers
KS

Kaitlin Swiantek

Ball FloraPlant
Co-authors
JR

John Ruter

University of Georgia
Allan Armitage Endowed Professor of Horticulture and Director, Trial Gardens at UGA
Wednesday September 25, 2024 10:30am - 10:45am HST
Coral 1

10:30am HST

PH 2 - Comparative Analysis of Volatile Organic Compounds of Eight Microgreens in the Brassicaceae Family
Wednesday September 25, 2024 10:30am - 10:45am HST
This study investigates the volatile organic compounds (VOCs) of eight microgreens in the Brassicaceae family, known for their robust flavors and potential health benefits, including detoxification properties and anti-cancer effects. The microgreens analyzed included five Brassica species—B. juncea (mustard), B. napus (kale), B. rapa (mizuna), B. oleracea L. var. capitata (red cabbage), and B. oleracea L. var. italica (broccoli)—as well as Eruca sativa (arugula), Lepidium sativum (cress), and Raphanus sativus (radish). The above-ground plant tissues were homogenized in saturated salt water and the VOCs were examined using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GCMS). A total of 117 VOCs were identified across all tested species, with individual species VOC counts ranging from 42 to 67. Radish showed the highest total ion current at 676 million (mTIC), with other species varying down to 190 mTIC in arugula. Notably, sulfur and/or nitrogen-containing compounds (SCCs and/or NCCs) constituted over 90% of the total VOCs collected from all species, with Brassica species containing more than 96% SCCs and 93% NCCs. Conversely, radish and arugula had less than 88% NCCs, and cress contained only 66% SCCs. Dominant compounds were primarily isothiocyanates, with significant variability in major VOCs across different species. For instance, allyl isothiocyanate was prevalent in mustard, mizuna, and red cabbage; 4-isothiocyanato-1-butene in kale and mizuna; isothiocyanatomethyl-benzene in cress; 1-isothiocyanato-4-(methylthio)-butane in arugula and broccoli; and (E)-4-isothiocyanato-1-(methylthio)-1-butene in radish. The reduced SCCs in cress were attributed to the higher presence of benzyl nitrile and benzyl isocyanate, while the lower NCCs in radish were linked to increased levels of dimethyl disulfide and dimethyl trisulfide. This diversity in SCCs and NCCs contributes to the varied volatile flavors and potential health benefits of these microgreens.
Speakers
JB

Jinhe Bai

USDA-ARS
Co-authors
AP

Anne Plotto

USDA-ARS
NA
ER

Erin Rosskopf

USDA-ARS
NA
FD

Francesco Di Gioia

Pennsylvania State University
JH

Jason Hong

USDA Agricultural Research Service
NA
LW

Libin Wang

Nanjing Agricultural University,
NA
WZ

Wei Zhao

USDA-ARS
NA
Wednesday September 25, 2024 10:30am - 10:45am HST
Nautilus 1

10:30am HST

VSF 2 - Transcriptome Analysis of Muscadine Pedicels Reveals Candidate Genes Modulating the Fruit Abscission Process
Wednesday September 25, 2024 10:30am - 10:45am HST
Muscadines (Muscadinia rotundifolia Michx) are native to the southeastern United States and have been cultivated for fresh consumption, juice, wine, and other processed products for over 100 years. Manual harvesting is one of the main challenges for fresh market production due to high labor costs. This study aimed to determine muscadine fruit and pedicel characteristics influencing fruit detachment force and to unravel the genes, hormones, and regulatory networks governing muscadine abscission. We characterized the fruit detachment force of muscadine berries across eighteen genotypes and at four developmental stages. Following this, we performed a transcriptome analysis using the mature pedicel tissue of two genotypes, a genotype with high fruit detachment force at maturity and a genotype with low fruit detachment force at maturity, to identify differentially expressed and uniquely expressed genes contributing to fruit detachment. Our results suggest that the abscission process and abscission zone development likely occur at different rates in a genotype and developmental stage dependent manner. Our findings provide valuable knowledge on the progression of fruit abscission and insights for controlling fruit detachment force. This will aid in the development of machine-harvestable cultivars which will increase the sustainability and efficiency of muscadine production.
Speakers
AB

Alana Brinley

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
PC

Patrick Conner

University of Georgia
TL

Tie Liu

University of Florida
NA
Wednesday September 25, 2024 10:30am - 10:45am HST
Kahili

10:30am HST

WUM 1 - Comparative Assessment of Satellite-Derived Crop Evapotranspiration and Estimated Evapotranspiration in Almond and Walnu
Wednesday September 25, 2024 10:30am - 10:45am HST
Almond and Walnut are the major irrigated crops in the Northern San Joaquin Valley (NSJV) of California. The recurring droughts and climate change in California will likely increase the uncertainty in water supply to almond, walnut, and other specialty crops. Site-specific irrigation is critical to cope with these challenges. Knowing the water consumption of these water use intensive crops is imperative for optimizing irrigation management since it affects nut quality, productivity, and composition. This requires accurate estimates of crop water use (Evapotranspiration, ET). Traditional methods for estimating crop water use are spatially limited, whereas satellite remote sensing of ET offers the advantage of large-scale coverage and is increasingly adopted in irrigated agriculture. This study compares OpenET models, an open-source database providing ET estimates, against calculated ET from weather stations that are commonly used by growers in their irrigation management. Evaluation of OpenET against estimated ET might provide a good opportunity for growers to improve water use efficiency. Such improvements could lead to the adoption of publicly available irrigation management tools and ensure healthier tree development, better resource utilization, and more resilient orchards in the face of climate change. This presentation delves into the preliminary findings of the OpenET evaluation against calculated ET from weather stations in estimating water use for almonds and walnuts, while also examining the potential and challenges associated with each approach for implementation in growers' fields.
Speakers
AM

Abdelmoneim Mohamed

Irrigation and Soils Advisor, University of California ANR
Wednesday September 25, 2024 10:30am - 10:45am HST
South Pacific 4

10:40am HST

NUR/RHIZ - Suppression of Stem Elongation of UV-B Treatment Timing and Intensity on Tomato Scion and Rootstock in Plant Factory with Artificial Lighting
Wednesday September 25, 2024 10:40am - 10:50am HST
This study aimed to determine the optimal conditions of UV-B exposure for regulating the growth of tomato grafted seedling in Plant Factory with Artificial Lighting by investigating growth characteristics, rhizosphere development, and chlorophyll fluorescence of seedlings. Tomato scion and rootstock were used in the experiment. UV-B treatment timing was divided into three stages from sowing to grafting. UV-B intensities were set at 1.44, 2.88, and 5.76 kJ·m−2·d−1. Results showed that morphology of plants did not exhibit significant differences up to 2.88 kJ·m−2·d−1 for tomato scion and rootstock. However, side effects such as leaf wilting were observed at 5.76 kJ·m−2·d−1. The length of hypocotyl, which is closely related to scion and rootstock suppression of stem elongation, was shortest when treated with 5.76 kJ·m−2·d−1 during the mid-growth stage across all treatment. Interestingly, rhizosphere characteristics such as root volume, surface area, and average root diameter showed improvement trends regardless of treatment timing when exposed to UV-B at 1.44-2.88 kJ·m−2·d−1. Quality indicators of seedlings showed best when 2.88 kJ·m−2·d−1 during the late-growth stage. Comparisons of chlorophyll fluorescence parameters revealed no significant effects of UV-B treatment on cucumber seedlings and grafting except for PIABS. However, tomato seedlings and grafting exhibited significantly reduced FV/FM and DIO/RC at late-growth stage when exposed to 5.76 kJ·m−2·d−1. Therefore, it is concluded that utilizing UV-B in the range of 1.44-2.88 kJ·m−2·d−1 during cucumber and tomato scion and rootstock production in Plant Factory with Artificial Lighting could minimize plant damage while expecting to suppress grafting effects.
Speakers
DJ

dongcheol jang

kangwon national university
Co-authors
HY

hwichan yang

kangwon national university
NA
SJ

soon jae hyeon

kangwon national university
NA
YK

youngho kim

kangwon national university
NA
YB

YunHyeong bae

kangwon national university
NA
Wednesday September 25, 2024 10:40am - 10:50am HST
South Pacific 3

10:45am HST

CHMG 1 - Cultivating Connections: Empowering Professionals through NC Farm to School Training Initiative
Wednesday September 25, 2024 10:45am - 11:00am HST
As the Farm to School movement continues to gain momentum, professionals in education, agriculture, and public health are seeking innovative ways to integrate this holistic approach into their practices. In North Carolina, our local, regional, and statewide food system has strengths across various sectors. Local agencies and community organizations now have decades of experience partnering together to maximize opportunities for local farmers and local food businesses. Partnering together, these food system practitioners have clearly begun to see that a systems approach is vital to supporting all sectors and stakeholders, vital to addressing the deep roots of inequity that negatively impacts our communities of color and particularly our children. The central need is in how to facilitate integrated efforts–both across farm to school components and also with multi-sector stakeholders–given that research shows that integration of farm to school programming brings the longest and most significant health and learning impacts on children. Our approach has been to develop the North Carolina Farm to School Training Initiative, a rich space of collaboratively created online content that informs and educates across the farm to school program areas. Through a combination of interactive modules, case studies, and expert-led discussions, our first course, School Gardening, provided participants with the knowledge and skills needed to navigate the complexities of Farm to School programming. The results from surveying pilot participants suggest numerous impacts, both on an individual and community level. Preliminary results found participants increased their knowledge and gained a deeper understanding of farm-to-school initiatives, including building community engagement through school garden teams, integrating gardening into curriculum, and the horticulture knowledge to successfully grow a garden. Participants improved their practical skills such as gardening techniques and the application of educational programming in the garden. Part of the course included interactive discussion boards and a qualitative review showed a number of themes emerged including that the course participants strongly benefitted by connecting with a group of like-minded educators and community organizers by fostering collaboration and support for farm-to-school efforts. Community engagement was another emergent theme with participants and they named that they would like to become more involved in their local food systems, finding connections with community partners like growers and Extension for access to resources and materials. These results suggest that fostering a community of practice that transcends geographic boundaries and provides localized and engaging content has significant potential to support great professional engagement in farm to school.
Speakers
LD

Liz Driscoll

Extension Associate, NC State University/ NC Cooperative Extension
Co-authors
KB

Kirsten Blackburn

NC State University
NA
RH

Remi Ham

NC State University
Wednesday September 25, 2024 10:45am - 11:00am HST
South Pacific 2

10:45am HST

HSMP 1 - Double-season production of hops (Humulus lupulus L.) with photoperiod manipulation in a subtropical climate
Wednesday September 25, 2024 10:45am - 11:00am HST
Hops (Humulus lupulus L.) have an ancient history of cultivation in temperate climates primarily as an ingredient of beer. However, growing hops in subtropical or tropical climates has been challenging because of non-optimal day length conditions. We examined the potential of subtropical hop production with photoperiod manipulation. ‘Cascade’ hops were grown in Florida, United States with extended day length (>16.5 hours) using light-emitting diode (LED) bulbs to inhibit flowering until sufficient vegetative growth was achieved. Phenology, plant growth, yield, and cone quality data were collected during the first two years after planting. With as little as 0.47 μmol/m2/s, photoperiod extension was effective in inhibiting flowering, while promoting vegetative growth. Uniform flowering was induced upon the discontinuation of photoperiod extension. As a result, plants achieved two growing cycles per year, with the spring and fall growing seasons running from February to July and July to December, respectively. Yield increased by 92% from Year 1 to Year 2 but decreased by 37% from the spring to fall growing season. The maximum yield was 465 kg/ha in Year 2 Spring. Cone quality was greatly affected by both year and season, with α acid, β acid, and total oil concentrations ranging from 2.7% to 6.2%, 1.9% to 3.2% and 0.14 to 0.53 mL/100 g, respectively. These results demonstrate that, with an aid of photoperiod manipulation for flowering control, ‘Cascade’ hops exhibit high phenological plasticity and acclimation capacity to subtropical climatic conditions. This study provides a foundation for developing the double-season hop production system in a subtropical climate.
Speakers
SA

Shinsuke Agehara

University of Florida
Co-authors
AA

Aleyda Acosta-Rangel

University of Florida
NA
JR

Jack Rechcigl

University of Florida
NA
Wednesday September 25, 2024 10:45am - 11:00am HST
South Pacific 1

10:45am HST

NUTS 1 - Evaluating Soil Management Impacts on the Pecan Orchard Mycobiome in the Semi-Arid Southwestern United States
Wednesday September 25, 2024 10:45am - 11:00am HST
Pecans hold significant agricultural importance in the water-limited Southwestern United States, underscoring the need for sustainable soil management practices in pecan cultivation. Recognizing the intricate relationship between soil treatments and the soil microbiome is essential to develop effective orchard soil management strategies. Soil fungi, particularly root-associated mycorrhizal fungi, are vital in facilitating water and nutrient uptake, protecting against pathogens, and enhancing overall orchard health and productivity. Soil management may impact the fungal community composition of Southwestern pecan orchard soils. Various soil management strategies are implemented in pecan orchards, including varying soil cover or applying mycorrhizal and bacterial inoculants. These techniques alter the soil environment, which may change the soil fungal biodiversity. This study investigates the impact of diverse soil management techniques on the soil mycobiome within a twelve-year-old ‘Pawnee’ pecan orchard in New Mexico. In a randomized complete block design, eight treatments of various soil cover – bare soil, cover crops, compost, or a combination of cover crops and compost – each either with or without mycorrhizal and bacterial inoculants, were applied to evaluate their effects on soil fungal diversity. Laboratory analyses, including DNA extraction, PCR amplification, and Illumina sequencing, were performed, alongside physiochemical testing for soil pH, electrical conductivity, and mineral nutrient content. The resulting sequence data were analyzed to provide insights into the complex interactions between soil management practices and microbial communities. Sampling conducted during the 2022 Spring and harvest seasons revealed significant differences in alpha and beta diversity between roots and bulk/rhizosphere soil (P < 0.10). Significant differences in alpha and beta diversity of fungi based on treatment were also observed, highlighting the potential influence of soil management practices, including soil cover and inoculant use, on fungal community composition. Our study offers valuable insights into the temporal changes in the community structure of pecan orchard fungi when treated with different soil amendments. Understanding how soil management practices influence the soil mycobiome can inform more sustainable pecan cultivation practices. By optimizing soil management strategies to support beneficial fungal communities, growers may enhance soil health, water and nutrient availability, and plant resilience to environmental stress.
Speakers
avatar for McKenzie Stock

McKenzie Stock

New Mexico State University
Co-authors
CV

Ciro Velasco-Cruz

New Mexico State University
NA
JR

Jennifer Randall

New Mexico State University
NA
NP

Nicole Pietrasiak

University of Nevada Las Vegas
NA
PG

Paul Gabriel

New Mexico State University
NA
RH

Richard Heeremaa

New Mexico State University
NA
Wednesday September 25, 2024 10:45am - 11:00am HST
Lehua Suite

10:45am HST

O/LT 1 - The Art and Technique of Producing Unique Lagerstroemia Plants
Wednesday September 25, 2024 10:45am - 11:00am HST
Crape myrtle (Lagerstroemia L.) stands as a ubiquitous presence in landscapes worldwide. Beyond its captivating smooth and exfoliating bark, a spectrum of flower colors, and impressive variable mature heights, the artistic modeling potential of crape myrtle has found favor in the high-end landscape market. Crafting a crape myrtle tree becomes a gratifying and imaginative endeavor. The preeminent modeled shapes include vases, screenings, letters, columnar forms, dragon-inspired (animalistic), symbolic representations, pavilions, tunnels, tree bonsai, ornamental root architecture, and even cartoon characters. Constructing a foundational armature from steel demands your artistic prowess and creativity, serving as the structural basis for the tree. Opting for fast-growing crape myrtle cultivars with pliable branches becomes imperative for success. Consistent pruning becomes a requisite to mold the growth pattern according to our artistic aspirations. Utilizing modeling wire facilitates the creation of the trunk and branch framework, with strategically tied crossed knots enhancing natural grafting unions. Developing distinctive Lagerstroemia plants requires a more extended timeframe and demands advanced modeling and pruning techniques compared to conventional growth processes. This production journey provides ample creative freedom and the ultimate performance should align with our artistic vision and the preferences of our clientele. Future studies should delve into plant growth dynamics and the development of trunk/branch anatomical structures to further enhance our understanding of this artistic horticultural practice.
Speakers
DZ

Donglin Zhang

University of Georgia
Co-authors
XL

Xi Li

Sichuan Agricultural University
NA
XH

Xiaoling Hou

Chongqing Yuexin Valley Ecological Agriculture Co. Ltd
NA
Wednesday September 25, 2024 10:45am - 11:00am HST
Coral 1

10:45am HST

PH 2 - Nutritional Quality and Shelf-Life of “Living Lettuce” Through 28 Days of Cold Storage
Wednesday September 25, 2024 10:45am - 11:00am HST
Lettuce (Lactuca sativa) is cultivated in controlled environment agriculture via vertical production or hydroponic well systems. To extend shelf-life, growers harvest “living lettuce” by keeping roots intact, but there is limited data supporting this harvesting technique. The objective of this study was to assess the use of clamshell and root treatments on the shelf-life and nutritional quality of lettuce. Treatments included storage either inside or outside of plastic clamshells and with roots removed or intact. Lettuce was stored for 28 days at 4 oC, 85% relative humidity. Percent weight loss (%weight loss), visual ratings (1 to 5 scale, 1 = poor and 5 = excellent), and colorimeter analysis (L*, a*, b*, c*, hue angle) were measured every 3 days. Total assays of chlorophyll, carotenoids, anthocyanins, flavonoids and phenolic activity were analyzed via UV VIS spectrophotometry every 7 days throughout storage. Few differences were seen in root treatment. As days in storage progressed, %weight loss progressed to 16.9%. Closed clamshells decreased %weight loss (5.5%) compared to open (18.1%). Visual ratings of yellowing/nutrient deficiency, relative greenness, wilt/head looseness, and salability decreased through storage. Lettuce stored in closed clamshells decreased %weight loss by 12% and delayed wilt/head looseness by 11 days. Similarly, lettuce stored in closed clamshells with roots were salable until 18 days in storage, while open clamshells were no longer salable after 7 days. Short root length (~4 cm) may be the dominant factor for the lack of significance as previous research suggested harvesting “living lettuce” with 9 cm roots increased storage and quality. Color data differed, and lettuce stored in closed clamshells with roots had more intense red color a* (-3.7 vs. -2.7), blue color b* (12.6 vs 10.1), and were purer in color c* (13.3 vs. 10.5) compared to open clamshells with roots. No differences were seen in total anthocyanin (mg/L), total chlorophyll (g/g) or total carotenoid (g/g) content in clamshell or root treatment (p > 0.05). Through 14 days of storage, total anthocyanins degraded by 7.55 mg/L (Day 0 = 10.78 vs. Day 14 = 3.22), while no loss of total chlorophyll (9204.84 g/g) or total carotenoids (1947.25 g/g) were seen. Anthocyanins are water soluble pigments and with increased weight/water loss, anthocyanins solubilize leading to degradation. Chlorophylls and carotenoids were not lost, potentially due to low enzyme activity of chlorophyllase. This experiment indicates consumers should eat lettuce within 7-10 days of harvest for highest nutritional and postharvest quality.
Speakers
MT

Marlee Trandel Hayse

Auburn University
Co-authors
CR

Camila Rodrigues

Auburn Univeristy
NA
CB

Caroline Blanchard

Auburn University
DW

Daniel Wells

Auburn University
NA
MH

MD Hasibur Rahman

Auburn University
NA
TR

Tanzeel Rehman

Auburn University
NA
Wednesday September 25, 2024 10:45am - 11:00am HST
Nautilus 1

10:45am HST

VSF 2 - World Grape Rootstocks Pedigree Review
Wednesday September 25, 2024 10:45am - 11:00am HST
Grapes belong to the Vitis genus, which includes about 80 species and is considered as two sub-genera, including Euvitis and Muscadinia. Muscadine grapes are sometimes considered as a separate genus in different classification systems and include three species: Muscadinia rotundifolia, Muscadinia munsoniana, and Muscadinia popenoei. The Euvitis sub-genus includes the most commercially important grape varieties. Euvitis is divided into three groups. 1) The American group consists of about 30 species that are important for rootstock breeding; 2) The Asian group consists of about 50 species, which, up to this point, have been underutilized for grape cultivation; and 3) The Eurasian group consists of a single species, Vitis vinifera L., which includes two sub-species of V. vinifera: V. vinifera subsp. sylvestris, considered to be the wild form of grape; and V. vinifera subsp. vinifera, refers to cultivated forms. Of all species in the genus Vitis, the V. vinifera, is undoubtedly the most important worldwide for commercializing grapes and represents the most cultivated varieties worldwide. Other grape species contributed to breeding programs beyond the traditional efforts of rootstock hybridization from wild species. An aphid-like pest, phylloxera (Daktulosphaira vitifoliae), causes damage by feeding on the structural roots of V. vinifera, eventually leading to vine death. In an effort, American Vitis species that coevolved with phylloxera were eventually used as rootstocks for the widely planted V. vinifera scion cultivars. Later, crosses between these wild species became common, and historical breeding efforts led to the modern grape rootstock breeding programs currently active worldwide. Two-thirds of American species have already been used for rootstock breeding. However, it has been reported that the most commonly available rootstocks are derived from just three American species (Vitis berlandieri, Vitis rupestris, and Vitis riparia). Therefore, the most common grape rootstocks have a narrow genetic base, and efforts to extend the gene pools for breeding programs by using other species are of ongoing importance to the industry and scientific community. There are around 1500 grape rootstocks developed in the world, of which around 50 are commonly used as commercial rootstock and play a fundamental role in resistance to biotic and abiotic stresses and adaptation of grapevine to different environmental conditions, a factor that has opened commercial grape growing to regions that might otherwise be overlooked.
Speakers
AR

Alireza Rahemi

Morehead State University
Co-authors
Wednesday September 25, 2024 10:45am - 11:00am HST
Kahili

10:45am HST

WUM 1 - Physiological Thresholds Provide Targets for Climate-Resilient Irrigation Management in Hazelnut
Wednesday September 25, 2024 10:45am - 11:00am HST
The rapidly changing climate is creating challenges for the selection and management of woody perennial crops. For North American (NA) cultivars of hazelnut (Corylus avellana), there is insufficient information on water stress management to maintain physiological performance and optimize productivity under limited soil water availability. Current plantings of NA hazelnuts are predominantly comprised of cultivars resistant to biotic stress (e.g., Eastern Filbert Blight) such as ‘Jefferson’ and ‘Yamhill’ cultivars, but their responses to abiotic stressors exacerbated by climate change is unknown. Our research objectives were to: 1. identify cultivar-specific physiological thresholds in response to water stress such as negligible leaf gas exchange (i.e., stomatal closure) and onset of leaf wilting (i.e., cell turgor loss) for phenotyping in greenhouse conditions; and 2. relate vapor pressure deficit to plant water status in order to generate a water-potential baseline capable of differentiating between atmospheric and soil moisture impacts on water stress in field conditions. Using the water potential (Ψ) curve (WPC) method, stomatal closure was initiated at less negative Ψ in ‘Jefferson’ (-0.85 MPa) compared to ‘Yamhill’ (-1.1 MPa). Similarly, turgor loss was found to occur at less negative Ψ in ‘Jefferson’ (-1.26 MPa) compared to ‘Yamhill’ (-1.48 MPa). These cultivar-specific differences were confirmed with direct measurements of stomatal conductance using a porometer and an evaluation of turgor loss point using the pressure-volume curve method. In the field, we established a water potential baseline to distinguish between the effects of soil moisture and vapor pressure deficit on Ψ. Our field results found a deviation from baseline of -1.0 MPa resulted in stomatal closure in Yamhill, which was consistent with our prediction from the WPC. ‘Yamhill’ trees that had Ψ on average -0.68 MPa below baseline over the growing season were also observed to have 34% smaller nuts, 46% higher shell-to-kernel ratio, and an estimated 50% of total in-shell yield. Upcoming research will seek to replicate results experimentally with both cultivars. In summary, our results indicate that the WPC is a valid tool for physiological phenotyping and preliminary results suggest that thresholds from the WPC provide viable cultivar-specific targets for improving irrigation management in hazelnuts. These results highlight methods to help determine sustainable irrigation management targets that can help conserve water resources strained by climate change while also maintaining plant productivity.
Speakers
SB

Steven Bristow (He/Him)

University of British Columbia
NA
Co-authors
TK

Thorsten Knipfer

University of British Columbia
NA
Wednesday September 25, 2024 10:45am - 11:00am HST
South Pacific 4

10:50am HST

NUR/RHIZ - Effects of Nitrogen on the Nodulation of Ceanothus velutinus
Wednesday September 25, 2024 10:50am - 11:00am HST
Ceanothus velutinus, commonly known as snowbrush ceanothus, is a nitrogen-fixing species native to North America. It plays a vital role in ecosystem by improving soil fertility through nodulation, a symbiotic process with bacteria that fixes atmospheric nitrogen. The purpose of this study was to identify the effects of various nitrogen concentrations on the nodulation and plant morphological and physiological responses. Ceanothus velutinus seedlings were transplanted in calcined clay and inoculated with 30 mL of soil containing Frankia. Seedlings were treated with 0.0 to 8.4 g·L-1 of controlled released fertilizer (CRF, 15N-3.9P-10K) or a nitrogen-free nutrient solution supplemented with or without 2mM ammonium nitrate (NH4NO3). Plant growth and photosynthesis increased linearly or quadratically along with the increasing CRF application rates with a notable increase observed at 4.2 g of CRF. Nodules were observed only in plants receiving 0.0, 0.3, 0.5, 1.1, or 2.1 g of CRF. However, the number of nodules formed in the treatments was too small to analyze statistically. The study indicates that while CRF significantly boosts C. velutinus growth, nodulation and nitrogen fixing capacity of the plant remains unknown. Further investigation is needed to determine the effect of nitrogen on the nodulation of C. velutinus using peat-based soilless substrate.
Speakers
PN

PRAKRITI NEPAL

Utah State Univeristy
Co-authors
YS

Youping Sun

Utah State Univeristy
Wednesday September 25, 2024 10:50am - 11:00am HST
South Pacific 3

11:00am HST

NUR/RHIZ - Evaluating the Effects of Varying Container Height and Volumes on Southern Highbush Blueberry Production
Wednesday September 25, 2024 11:00am - 11:10am HST
In recent years, soilless cultivation methods have emerged as a promising approach for blueberry production, offering opportunities to optimize resource use, enhance yields, and utilize land with poor soil quality. Despite extensive research on soilless substrate production for blueberries, there remains a knowledge gap regarding the specific influence of container geometry. This study aimed to investigate the effects of container capacity (CC) and air space (AS) within the substrate, which vary based on container height and volume. Simultaneously, two studies were conducted: one focusing on container height and the other on container volume. For the container height study, three containers were fabricated to have the same volume but varying heights. In the container volume study, three containers were created using different diameters of Schedule 40 PVC pipe, resulting in three distinct volumes while maintaining the same height. Both studies utilized two substrates, aged pine bark, and coconut coir, in separate trials. The findings highlight a nuanced relationship between container geometry and substrate composition, underscoring the importance of considering these factors in blueberry cultivation practices. This research contributes to refining cultivation techniques, ultimately enhancing the efficiency and productivity of soilless blueberry production systems.
Speakers
BS

Brandan Shur

North Carolina State University
Co-authors
BJ

Brian Jackson

NC State
NA
Wednesday September 25, 2024 11:00am - 11:10am HST
South Pacific 3

11:00am HST

CHMG 1 - The gARTening Program: Fostering Community Engagement through Innovative Education
Wednesday September 25, 2024 11:00am - 11:15am HST
Orange County, Florida, an urban county with a boasting a population of 1.4 million residents, faces a distinctive demographic trend with a homeowner rate of 56%, notably below the national average of 64%. This indicates a higher proportion of renters and apartment dwellers within our community. In order to expand the reach of our horticultural efforts beyond the limitations of traditional homeownership and include all residents, our Master Gardener Volunteer Program developed the Garden Art (gARTening) program, aimed to appeal to a wider audience. Beyond mere attraction of new attendees, our focus was to increase: office foot traffic, awareness of UF/IFAS Extension Services, and create a unique hands-on program that maintained affordability while generating revenue. We developed "The gARTening Program," featuring unique garden-related art projects, to achieve our objectives. Classes ranged from 1-2 hours and $5-35, with topics such as terrariums, kokedamas, pressed flower art, and more. Collaborating with Master Gardener Volunteers (MGVs), we created educational materials such as PowerPoints, handouts, and economical shopping lists. Our diverse approach attracted a broad audience, including young families, mother-daughter pairs, couples, and individuals, fostering inclusivity and engagement. The outcomes of the gARTening Program exceeded expectations: • Revenue generated in one year: $3200 • 47% of participants were new to UF/IFAS Extension and had never utilized our services before. • 70% joined due to the unique hands-on experience. • 95% indicated they gained knowledge of UF/IFAS Extension services as a result of attending the workshop. • Additionally, participants showed continued engagement, with many signing up for additional classes, volunteering with 4-H or becoming an MGV, and promoting our services to others. The gARTening Program not only met, but surpassed its objectives, illustrating its efficacy in community engagement and revenue generation. By offering unique experiences, we heightened awareness of UF/IFAS Extension Services, attracting new participants and fostering long-term engagement. The program's success underscores the potential for innovative education methods to address funding challenges while advancing community outreach and awareness. This model holds broader implications for enhancing community well-being and supporting sustainable organizational growth.
Speakers
avatar for Clarissa Chairez

Clarissa Chairez

Extension Faculty, UF/IFAS Extension Orange County
Wednesday September 25, 2024 11:00am - 11:15am HST
South Pacific 2

11:00am HST

HSMP 1 - Brewing Conditions and UV treatment affect Shelf Life of Cold-brew US-grown Tea
Wednesday September 25, 2024 11:00am - 11:15am HST
Tea, Camellia sinensis, is grown around the world under diverse geographic and climatic conditions and can be cultivated as a specialty crop in the U.S. U.S. specialty tea growers cater to the high-quality specialty tea niche market, and innovations in mechanization and novel products increase profitability. The objective of this study was to develop a cold brew methodology that would maximize the flavor characteristics and shelf life of cold brew black teas to facilitate the development of new products. 'Black Magnolia' from the Great Mississippi Tea Co. (Brookhaven, MS) was used to determine combinations of cold brew conditions affecting taste and health-promoting compositions (polyphenol and caffeine), including selected combinations of tea-to-water ratio (1, 2, and 3g of tea per cup of water), temperature (40, 45, 50, 55, and 60°F), brewing time (6, 8, 10, 12, and 14 hours), and particle size (whole-leaf, coarse, and fine). Selected conditions were then used in a UV light experiment to compare shelf life (microbial growth at 2, 4, and 6 days after brewing) using hot water-brewed tea as a control. Results indicate that, for this specific black tea, 2g per cup at higher temperatures of 55 to 60°F resulted in comparable polyphenol contents to hot water brew, but lower caffeine concentrations. However, compared to lower temperatures, teas made at this range of temperatures resulted in a higher number of yeast and mold by day 4. Brewing at 45°F for 14 hours resulted in comparable polyphenol contents as hot water brew and was described with more positive words compared to a shorter brewing time during sensory surveys conducted on campus with over 100 students. Initial testing of UV light treatments for 0, 0.5, 1.0, and 2.0 hours of duration before cold brew indicated that UV light is insignificant in reducing microbial growth. Further research is needed to improve the UV treatment or use other methods to extend the shelf life of cold brew tea. The best brewing conditions obtained from this study could be of guidance for future large-scale consumer sensory evaluations that will compare the flavor of four U.S.-grown black teas to imported specialty teas and their health-benefiting compounds. This next study will provide essential and important information for U.S. tea growers and consumers on how U.S.-grown tea performs in comparison with internationally known black teas and potential enhancements to maximize the health benefits and popularity of U.S.-grown specialty tea.
Speakers
YC

Yan Chen

LSU AgCenter
Co-authors
ZX

Zhimin Xu

Louisiana State University School of Nutrition and Food Sciences
NA
Wednesday September 25, 2024 11:00am - 11:15am HST
South Pacific 1

11:00am HST

O/LT 1 - Effects of Different Pruning Regimes on Growth Reallocation and Carbon Storage in Buxus microphylla var. japonica ‘Winter Gem’
Wednesday September 25, 2024 11:00am - 11:15am HST
Hedge shaping and size maintenance is often accomplished with electric or gas-powered shears due to a lower cost compared to hand pruning. Shearing plants arbitrarily removes the apical growing points from external portions of the shrub to achieve a desired shape and size of the plant and often results in poor quality cuts, leaving ragged ends of woody tissues or leaves. Contrarily, hand pruning makes strategic, ‘clean’ cuts often back to lateral branches to achieve these goals. Use of plant growth regulators like paclobutrazol (PBZ) can reduce the frequency of pruning and could be a useful component of a hedge management program. The purpose of this study was to investigate the effects of shearing, hand pruning, and/or PBZ application on regrowth of foliage and non-structural carbohydrates (NSCs) of ‘Winter Gem’ boxwood over time. Fifteen shrubs each per pruning type x frequency combination were pruned with bypass hand pruners (hand pruned) or gas-powered shears (sheared) in 2021, 2022, and 2023 once or twice per growing season. In addition, another 15 shrubs each were sheared once followed by an immediate application of a foliar PBZ (i.e. Trimtect®) in accordance with the label using an electric backpack or left as non-pruned controls. In 2021 and 2022, shrubs were pruned by removing 15 percent of the overall height and 20% of the overall widths in two perpendicular directions of each shrub. In 2023, pruned shrubs were cut back to the previous season’s overall height and width. Regrowth was measured by weighing the fresh biomass removed at each pruning and NSCs were measured from ten woody twigs from the exterior of each shrub using the phenol-sulfuric acid quantification method. Two and three years after pruning, shearing shrubs twice had significantly more biomass produced year over year compared to hand pruning, while PBZ treated shrubs had the least amount of regrowth. NSCs trended to be highest in shrubs that were hand pruned once or in PBZ treated shrubs, while the least in shrubs that were sheared twice. PBZ-treated shrubs had tighter clusters of internodes resulting in approximately 30% reduction in stem elongation compared to controls. The differences in growth dynamics and carbon storage across these different pruning strategies can have different long- and short-term implications in managing boxwood hedges, which will be presented here.
Speakers
AL

Andrew Loyd

Plant Pathologist, Bartlett Tree Research Laboratories
Co-authors
CL

Caitlin Littlejohn

Bartlett Tree Research Laboratories
NA
CR

Chad Rigsby

Bartlett Tree Research Laboratories/Morton Arboretum
NA
Wednesday September 25, 2024 11:00am - 11:15am HST
Coral 1

11:00am HST

PH 2 - Comparing the Postharvest Phytonutrient Content of Red and Green Butterhead Lettuce Cultivars
Wednesday September 25, 2024 11:00am - 11:15am HST
Lettuce is a popular leafy vegetable that can play an important role in human nutrition and diets with regular consumption. Lettuce cultivars can vary considerably in their postharvest nutritional composition. It is critically important to determine which lettuce cultivars have the highest nutritional quality to allow growers to select those that are best for their market. The objectives of this experiment were twofold, to determine differences in the phytonutrient content of two butterhead lettuce cultivars, ‘Nancy’ (green butterhead) and ‘Skyphos’ (red butterhead), and if leaf location within the head (lower or mid leaves) differs in nutritional composition. The experiment was conducted in the spring of 2023 in a high tunnel, and setup as a completely randomized design with 4 replications. At horticultural maturity (40 days after germination), the lower and mid leaves were harvested. Lettuce samples were frozen and shipped to Auburn University where samples were assayed for total chlorophyll, carotenoids, anthocyanins, flavonoids, phenolics and antioxidant activity via UV VIS spectrophotometry. Carotenoids of violaxanthin, neoxanthin, lutein and -carotene were quantitated by UPLC/MS. The interaction of leaf location*cultivar (P < 0.05) indicated that the lower leaves of ‘Skyphos’ lettuce had the highest total anthocyanin content at 2.94 mg/L compared to ‘Nancy’ at 0.05 mg/L, respectively. No other differences (P > 0.05) were detected between the cultivars. Sample location differed in total carotenoids (mg/g) and total chlorophyll (mg/g) with the lower leaves having the highest nutritional composition at 1380.18 and 5973.58 mg/g, respectively compared to the mid leaves (509.02 and 1684.42 mg/g, respectively). Chlorophyll a (4399.67 mg/g) and b (1573.90 mg/g) was also highest in the lower leaves of both cultivars compared to the mid leaves. Our results indicate that both butterhead lettuce cultivar and leaf location strongly impacts human health. ‘Skyphos’, a red butterhead lettuce, had the high highest total anthocyanin content in the lower leaves. Anthocyanins are critical phytochemicals known for many health promoting properties such as free radical scavenging, and anti-cancer and anti-diabetic properties. This experiment also indicated the lower leaves of both cultivars had the highest amount of total chlorophyll and carotenoids. The lower leaves of red butterhead lettuces, such as ‘Skyphos’, should be eaten to obtain the highest nutrition for their diet.
Speakers
MT

Marlee Trandel Hayse

Auburn University
Co-authors
AW

Alan Walters

Southern Illinois University
Wednesday September 25, 2024 11:00am - 11:15am HST
Nautilus 1

11:00am HST

VSF 2 - Genome Database for Vaccinium: Genomics Data and Tools to Facilitate Research
Wednesday September 25, 2024 11:00am - 11:15am HST
The Genome Database for Vaccinium (GDV, www.vaccinium.org) is a community database resource for Vaccinium researchers and breeders. The database contains genomics data for blueberry, cranberry, bilberry, and lingonberry that are integrated with other types of data such as genetic maps, markers, and QTL/GWAS. The genomics data is accessible via a plethora of search interfaces and tools. GDV has over 40 genomes and allows users to view the genomes in JBrowse, query sequences against the genomes in BLAST and view genome synteny via the Synteny Viewer tool. Highly utilized genomes in JBrowse contain tracks of aligned markers, GWAS, and QTL. Standard GDV analyses on the genomes include synteny analysis and functional annotation of predicted genes with InterPro protein domains and GO terms as well as homology to known proteins. The genes and mRNAs of each genome, along with the functional annotations and orthologs/paralogs, are searchable on GDV. Representative genomes are available in the PathwayCyc tool which displays metabolic pathways and allows for transcriptomics or metabolomics data overlays. GDV also has the genomes and structural pangenomes from the Vaccinium Pangenome Project, a product of VacCAP. Expression datasets that are mapped to genomes are also available to explore using the Expression Heatmap tool. Also available in GDV is the Breeding Information Management System (BIMS) that allows breeders to manage and analyze the phenotypic and genotypic data and provides public access to GRIN phenotype data. This presentation will showcase how to access these genomics data through various tools.
Speakers
JH

Jodi Humann

Washington State University
Co-authors
CH

Chun Huai Cheng

Washington State University
NA
DM

Dorrie Main

Washington State University
KB

Katheryn Buble

Washington State University
NA
MI

Massimo Iorizzo

North Carolina State University
NA
PZ

Ping Zheng

Washington State University
NA
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
Wednesday September 25, 2024 11:00am - 11:15am HST
Kahili

11:00am HST

WUM 1 - Determination of Crop Coefficient and its Inter-annual Variability in Pecan Orchard in Georgia
Wednesday September 25, 2024 11:00am - 11:15am HST
Pecans have high economic importance in the US. Nonetheless, as one of the top pecan producers, there is little research on water use of pecan trees in the Southeast of the US. The water status of the tree impacts the yield, mostly during the kernel filling period (August and September). The knowledge gap of pecan water requirements stems largely from the Southwest. There, pecan tree needs in the hot and arid climate of the Southwest contrast sharply with those of the long, hot and humid Southeastern climate. Furthermore, the Southwest management practices use flood irrigation in contrast with most Georgia orchards which use micro-irrigation. This paper reports on the development of a crop coefficient specifically addressing the pecan tree needs in the Southeastern US. This study uses an eddy-covariance system and micro-lysimeter to determine the actual evapotranspiration of pecans. The potential evapotranspiration is determined using nearest local weather station data. This paper discusses the behavior of the crop coefficient throughout the different physiological stages of the tree from budbreak to harvest. Results of the crop coefficient obtained throughout the season differs from the Southwest, where the actual evapotranspiration during the growing season is significantly higher than the one observed in the Southeast. The daily and monthly crop coefficient throughout the growing period from 2019 through 2023 respectively are discussed. The year-to-year variability is also discussed. These results should support pecan growers and researchers alike to more tailored irrigation schedule in Southeast pecan orchards.
Speakers
ML

Monique Leclerc

Regents Professor, The University of Georgia
Co-authors
GZ

Gengsheng Zhang

The University of Georgia
NA
KP

Kriti Poudel

University of Georgia
LW

Lenny Wells

University of Georgia
NA
Wednesday September 25, 2024 11:00am - 11:15am HST
South Pacific 4

11:00am HST

Advice to Students
Wednesday September 25, 2024 11:00am - 11:30am HST
Wednesday September 25, 2024 11:00am - 11:30am HST
Coral 5

11:14am HST

Undergraduate Student (UG)
Wednesday September 25, 2024 11:14am - 12:45pm HST
A Comparative Study Analyzing Light Lengths for the Growth of Rex Butterhead Lettuce Utilizing GREENBOX Technology - Mya Griffith
Evaluating the Feasibility of Lettuce Crop Cultivation with Reclaimed Water Utilizing GREENBOX Technology - Mya Griffith
The Assessment of Different Growth Mediums for Plug Cultivation in a Controlled Environment - George Buss
Comparative Analysis of Lettuce Growth Using Compost Versus Conventional Soil - Sofia Huber
Feasibility of Plug Production Utilizing Digestate From Home Water-Energy-Food Systems (H-WEF) - Rory Dunn
From Flower to Fruit: Growing Degree Days and Peach Ripening - Matthew Almy
Enhancing rose propagation using moisture sensor-controlled irrigation and LED supplemental lighting in greenhouses - Braylen Thomson
Wednesday September 25, 2024 11:14am - 12:45pm HST
Lehua Suite

11:15am HST

CHMG 1 - Welcome Home to Gardening in Tennessee: Reaching New Audiences with New Collaborative Outreach Models
Wednesday September 25, 2024 11:15am - 11:30am HST
New residents in the state along with new gardeners are an increasingly large Extension audience. As our Extension horticulture team discussed the challenges in individually addressing these questions and meeting the needs of these new stakeholders, we realized new models and resources were needed. While Extension has a great array of publications and resources on lawns, landscapes and gardens, there wasn’t a publication that provided a good entry point for those new to the region or gardening. So, we set out to develop a ‘gateway publication’ to provide a general overview and connect folks to further resources without being overwhelming. A magazine format with easy to digest 2-page spreads on the most common areas of gardening was developed titled “Welcome Home: Gardening in Tennessee.” To extend the reach and impact of this new resource and engage Extension agents and stakeholders across the state, our horticulture team developed a new outreach program that paired live, distance teaching with local hands-on labs and activities. In October of 2023, we had a 5-session workshop series where new residents could come to their local office for an hour of teaching from our best horticulture content folks and then take part in a hands-on teaching demonstration with their local agriculture Extension agent. Nearly 300 participants in 32 counties took part in the series. Evaluation data revealed that over 70% of attendees had attended no or very few prior Extension programs. With a fee of only $30-50 locally, attendees reported a value of over $950 received from information delivered in the class. This presentation will focus on the novel delivery model and evaluation data along with perspectives on opportunities and challenges in reaching these new Extension audiences.
Speakers
NB

Natalie Bumgarner

Assistant Professor, University of Tennessee Knoxville
Co-authors
AL

Andrea Ludwig

University of Tennessee
NA
AD

Anna Duncan

University of Tennessee
NA
CS

Celeste Scott

University of Tennessee
NA
GU

Gregg Upchurch

University of Tennessee
NA
HT

Haley Treadway

University of Tennessee
NA
JS

Justin Stefanski

University of Tennessee
NA
LR

Lee Rumble

University of Tennessee
NA
MR

Melody Rose

University of Tennessee
NA
MM

Mitchell Mote

University of Tennessee
NA
SW

Seth Whitehouse

University of Tennessee
NA
TR

Taylor Reeder

University of Tennessee
NA
VS

Virginia Sykes

University of Tennessee
Wednesday September 25, 2024 11:15am - 11:30am HST
South Pacific 2

11:15am HST

HSMP 1 - Withering Duration and Drying Temperature Significantly Affect Postharvest Quality of Kratom (Mitragyna speciosa)
Wednesday September 25, 2024 11:15am - 11:30am HST
Kratom (Mitragyna speciosa) is an ethnobotanical plant with high medicinal value that has been historically utilized in Southeast Asia as a traditional remedy for fatigue mitigation and productivity enhancement. Recently, it has attracted widespread attention, particularly in North America and Europe, for its potential for pain management and alleviating opioid withdrawal symptoms and has become an important source for future drug development. Postharvest processing represents a key step in the kratom farm-to-pharm chain where products undergo chemical modifications before reaching consumers. In this study, we investigated how different withering durations, drying temperatures, and lighting conditions could affect kratom postharvest product qualities. Leaves were harvested from cultivar H and mixed well before randomly assigned to one of four withering durations (0, 12, 24, and 72 h) at 25 ℃ in the dark and subsequently one of five drying temperatures (-40, 25, 40, 60, and 80 ℃). Additionally, leaves were dried at 25 ℃ under either light or dark. Overall, withering at 25 ℃ significantly increased mitragynine concentration. Compared to 0 h withering, a 12 h withering followed by drying at -40, 25, 40, or 60 ℃ increased mitragynine concentrations by 117%, 17-123%, 16-61%, and 43-103%, respectively. The 12 h withering increased the concentration of speciogynine and paynantheine by 27-28% and 35-67%, respectively, when leaves were dried below 40 ℃. In contrast, speciociliatine levels initially decreased during 12 or 24 h withering but subsequently elevated after the withering duration increased to 72 h. Drying temperatures and light exposure generally had little effect on the biosynthesis of most of the alkaloids. However, an alternation in kratom powder color was noticed for those with a short withering duration and subsequently a high drying temperature. Other minor alkaloids including corynoxine A, corynoxine B, speciofoline, isospeciofoline, mitraphylline, and ajmalicine were below the lower limit of quantifications. Taken together, our study shows that withering and subsequent drying temperatures have significant effects on the color and content of bioactive compounds of kratom, and further research on optimizing kratom postharvest processing is needed.
Speakers
MZ

Mengzi Zhang

Biological Scientist, University of Florida
Co-authors
BP

Brian Pearson

Oregon State University
NA
JC

Jianjun Chen

University of Florida
NA
Wednesday September 25, 2024 11:15am - 11:30am HST
South Pacific 1

11:15am HST

O/LT 1 - Establishment, Growth, and Physiology of Container-Grown Trees Following Root Remediation at Planting
Wednesday September 25, 2024 11:15am - 11:30am HST
Root defects, especially circling roots, are a major concern when planting container-grown trees. In this study, we compared survival, crown dieback, and plant water potential of four common landscape tree species (Carpinus caroliniana, Liriodendron tulipifera, Ostrya virginiana, and Platanus × acerifolia) in response to root modifications (control, bare-root washing, shaving, and vertical slicing) prior to planting. P. × acerifolia trees were robust with respect to root correction treatments and had 100% survival except for some mortality following vertical root-ball slicing. In contrast, C. caroliniana, L. tulipifera, and O. virginiana trees had significant mortality and crown dieback in response to bare-root washing. The responses of these species to bare-root washing reflected extreme plant moisture stress immediately after planting. These three species are also considered ‘difficult to transplant’ as bare-root nursery stock. Our results suggest that trees that are generally known to be difficult to transplant as bare-root stock are poor candidates for extreme root disturbance such as bare-rooting when grown as container trees. In contrast, shaving and vertical slicing had little or no adverse effects on tree survival, crown dieback, or plant water potential.
Speakers
BC

Bert Cregg

Michigan State University
Dr. Bert Cregg is a professor of Horticulture and Forestry at Michigan State University. He conducts research and extension programming on the physiology and management of trees in landscapes and nursery and Christmas tree production.
Co-authors
RJ

Riley Johnson

Michigan State University
NA
Wednesday September 25, 2024 11:15am - 11:30am HST
Coral 1

11:15am HST

PH 2 - Production System Alters Phytonutrient Content of ‘Skyphos’ Butterhead Lettuce
Wednesday September 25, 2024 11:15am - 11:30am HST
Lettuce is one of the most widely consumed vegetables in the world and can provide various health benefits to consumers. The type of production system, such as high tunnel, green roof or open field environments, can influence the nutritional composition of lettuce. To determine the extent of phytonutrient content change, ‘Skyphos’ lettuce was grown in these various production environments to compare phytonutrient content at harvest. The production experiment was conducted at Southern Illinois University-Carbondale and set up with three treatment locations and four replications. Two production systems used organic fertility practices (high tunnel and green roof), while the field production system used conventional fertilizers. At horticultural maturity (40 days after germination), the lower and mid leaves were harvested to determine phytonutrient content. Lettuce samples were frozen and shipped to Auburn University where samples were assayed for total chlorophyll, carotenoids, anthocyanins, flavonoids, phenolics and antioxidant activity via UV VIS spectrophotometry. Carotenoids of violaxanthin, neoxanthin, lutein and b-carotene were quantitated by UPLC/MS. The interaction of production system*leaf sampling location differed (P < 0.05) in total anthocyanins, total carotenoids and total chlorophyll. Total anthocyanins were highest in the lower leaves of ‘Skyphos’ lettuce cultivated on the green roof at 3.57 mg/L. In comparison, total carotenoids, total chlorophyll and chlorophyll a were highest in the lower leaves of lettuce cultivated in the high tunnel at 1316.48, 6093.45 and 4401. 97 mg/g, respectively. Cultivating lettuce in the high tunnel provided the highest Chlorophyll b content (1638.37 mg/g) compared to the field (888.80 mg/g) or green roof (893.43 mg/g). The phytonutrient content of lettuce can be influenced by location, temperature, soil type, humidity and UV radiation. The green roof increased total anthocyanin content which may be due to the higher temperatures and irradiation levels on compared to the field or high tunnel. Total Chlorophyll and carotenoid content was increased in the high tunnel likely due to increases of UV-A and UV-B exposure from the poly film leading to an increase in photosystem response. This experiment suggests the specific phytonutrient content (e.g., anthocyanin or carotenoids) in a red lettuce like ‘Skyphos’ differs based on production system and can be used in market development to increase consumer consumption by highlighting the specific phytonutrients highest in each production system.
Speakers
MT

Marlee Trandel Hayse

Auburn University
Co-authors
AW

Alan Walters

Southern Illinois University
Wednesday September 25, 2024 11:15am - 11:30am HST
Nautilus 1

11:15am HST

UG - Evaluating the Feasibility of Lettuce Crop Cultivation with Reclaimed Water Utilizing GREENBOX Technology
Wednesday September 25, 2024 11:15am - 11:30am HST
The development of GREENBOX technology addresses the challenges posed by rapid population growth, which intensifies the demand for agricultural resources essential for cultivating and distributing fresh produce, including arable land, water, and nutrients, to both rural and urban areas. Utilizing principles of Controlled Environment Agriculture (CEA), GREENBOX technology optimizes growth conditions for leafy green crops by leveraging existing urban infrastructure and readily available commercial equipment. GREENBOX technology allows for precise control over environmental variables such as temperature, humidity, light intensity/spectrum, and nutrient delivery, thereby enhancing the growth performance of leafy greens. We were interested in assessing the feasibility of utilizing reclaimed water for crop production as preliminary experiments employing GREENBOX technology that employed a standard nutrient solution comprising a blend of 5-12-26 and 15-0-0 Calcium Nitrate for crop production. This study's primary objective was to conduct a comparative analysis of Lactuca sativa Rex Butterhead Lettuce production using the standard nutrient solution as the control (Treatment 1), and Reclaimed water or treated wastewater supplemented with additional nutrients (Treatment 2). The assessment focused on measuring crop biomass and productivity and environmental conditions associated with each nutrient solution to identify any significant differences. Biomass parameters, including wet weight, dry weight, leaf area, leaf count, and chlorophyll concentration, were measured alongside derived data such as Leaf Area Index (LAI), Specific Leaf Area (SLA), and biomass productivity. Statistical analysis of the biomass data was conducted to discern differences in biomass parameters between crop growth using both hydroponic solutions. Both treatments yielded Rex Butterhead lettuce well above the anticipated harvest weight of 180g, indicating their suitability for crop production in urban warehouse settings. The findings of this experiment contribute valuable insights into the feasibility of utilizing various types of wastewater for hydroponic crop growth. Future experiments employing GREENBOX technology may utilize these findings to enhance the efficiency, productivity, and sustainability of GREENBOX units. This study has impactful implications for sustainability, as it offers a potential solution to mitigate water scarcity and promote efficient resource utilization in agricultural practices. Keywords: CEA, Hydroponics, lettuce, Reclaimed Wastewater, urban agriculture
Speakers
MG

Mya Griffith

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
BR

Barry Rosen

Florida Gulf Coast University
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
GB

George Buss

Florida Gulf Coast University
JG

John Griffis

Florida Gulf Coast University
NA
KJ

Kathryn Jackson

Independent Researcher
NA
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 11:15am - 11:30am HST
Lehua Suite

11:15am HST

VSF 2 - Use of glycine betaine and kelp extract mitigates heat stress in red raspberry (Rubus idaeus)
Wednesday September 25, 2024 11:15am - 11:30am HST
Heat stress poses a significant threat to global food production and security by disrupting plant physiological and biochemical processes. Global simulation models predict a 4 to 5°C increase in atmospheric temperatures by the year 2100, as well as increases in the frequency of extreme heat events. This has necessitated preemptive measures to enhance the resiliency of horticultural crop production. Biostimulants, a class of agricultural products, show great promise in mitigating heat stress effects by enhancing physiological and biochemical stress tolerance. However, limited research exists on the efficacy of commercial biostimulant products in improving heat stress tolerance in horticultural crops. This study evaluated the impacts of three exogenously applied commercial biostimulants representing a range of active ingredients and included FRUIT ARMORTM, Optysil®, and KelpXpressTM [active ingredients glycine betaine, silicone, and kelp (Ascophyllum nodosum) extract, respectively], plus a water control, on physiological, biochemical, and growth parameters in different raspberry genotypes exposed to continuous heat stress (Tmax ≥ 35°C/day) in a glasshouse. Over a 28-day period, the biostimulants and the water control were applied weekly to three raspberry genotypes (‘Meeker’, WSU 2188, and ORUS 4715-2). The results indicated that ‘Meeker’ consistently maintained high chlorophyll fluorescence (Fv/Fm) and photosynthesis under control and biostimulant treatments. In contrast, WSU 2188 and ORUS 4715-2 exhibited increased Fv/Fm and photosynthesis when treated with FRUIT ARMORTM. Additionally, KelpXpressTM application improved Fv/Fm in WSU 2188. ‘Meeker’ and WSU 2188 treated with FRUIT ARMORTM and KelpXpressTM accumulated more anthocyanins and had greater shoot and total biomass compared to ORUS 4715-2. These findings underscore genotype-specific and biostimulant-dependent responses to heat stress mitigation. The superior physiological performance by ‘Meeker’ under both control conditions and biostimulant treatments indicates heat tolerance in the genotype. Furthermore, higher anthocyanins accumulation, improved Fv/Fm, enhanced gas exchange, and greater total biomass of WSU 2188, as well as improved Fv/Fm of ORUS 4715-2, suggests that application of the biostimulants contributed to enhanced repair and maintenance of photosystem II (PSII) structural integrity, improved photosynthetic performance, and increased antioxidative capabilities, which may have contributed to higher total biomass of raspberry treated with FRUIT ARMORTM relative to the untreated control. In summary, the positive impacts on physiological, biochemical, and growth parameters support the potential role of biostimulants in enhancing thermotolerance in raspberries and other horticultural crops exposed to heat stress.
Speakers
MG

Makonya Givemore Munashe

Washington State University
Co-authors
Wednesday September 25, 2024 11:15am - 11:30am HST
Kahili

11:15am HST

WUM 1 - Assessing Water Status in Citrus Plants Using Thermal Imaging in Greenhouses
Wednesday September 25, 2024 11:15am - 11:30am HST
Thermal cameras can easily determine plant canopy temperature, and the resulting data can be used for irrigation scheduling in addition to other water management tools. This study aimed to develop a method to use thermal imaging for canopy temperature measurements in one-year-old citrus plants to assess citrus water status. We evaluated the influence of five water levels (25%, 50%, 75%, 100%, and 125%) based on the crop evapotranspiration replacement of two citrus species [‘Red Ruby’ grapefruit (Citrus paradisi) and ‘Valencia’ sweet orange (Citrus sinensis)] for 48 days in a greenhouse. To determine the irrigation requirements for the treatment 100%, we estimated the water loss from pots by calculating the difference in soil moisture between the day before and the day of the measurement. We irrigated the pots when the soil moisture was close to the maximum allowable water depletion, keeping the soil moisture between the field capacity and the maximum allowable depletion. A portable thermal camera was used to take images that were later analyzed using open-source software. We determined the canopy temperature, leaf photosynthesis and transpiration, and plant biomass. A positive relationship between the amount of water applied and the temperature response of plants exposed to different water levels was observed. Grapefruit and sweet orange plants that received less water presented water restrictions and reached 6 °C higher canopy temperatures than the air. The thermal images easily identified water-stressed plants. This study allowed quick measuring of the canopy temperature using readily available equipment and can be used as a tool to assess water status in citrus plants in greenhouses. An automated routine to process the thermal images in real-time and remove the background weeds to determine the canopy temperature can potentially allow using it for irrigation management.
Speakers
avatar for Gustavo Haddad Souza Vieira

Gustavo Haddad Souza Vieira

Full Professor, IFES campus Santa Teresa
Agronomist,Ph. D. in Agricultural Engineering. Full Professor. Irrigation, Agrometeorology, Horticulture, Coffee Crop.
Co-authors
RS

Rhuanito Soranz Ferrarezi

University of Georgia
NA
Wednesday September 25, 2024 11:15am - 11:30am HST
South Pacific 4

11:15am HST

ASHS Plants, People, Science Podcast Live Episode
Wednesday September 25, 2024 11:15am - 12:15pm HST
Speakers
Wednesday September 25, 2024 11:15am - 12:15pm HST
Sea Pearl 4

11:29am HST

Vegetable Crops Management 2 (VCM 2)
Wednesday September 25, 2024 11:29am - 1:20pm HST
Effect of Plastic Mulch, Living Mulches and Cover Crops on Soil Characteristics, Weed Pressure and Yield in Organic Globe Artichokes Production - Arianna Bozzolo
Effects of Off-Season Winter Cover Crops and In-Season Nematicide Application on Plant-Parasitic Nematodes - Abolfazl Hajihassani
Lessons Learned from Living Mulch Trials on Midwest Vegetable Farms - Connor Ruen
Evaluating Cover Crop Biomass and Roller Crimper Technology for Effective Weed Control in Vegetable Systems - Arianna Bozzolo
Fall Cover Crops to Follow Carrot Harvest on High Organic Matter Soils - Mary Ruth McDonald
Cover Crops For Vegetable Research Farms Need Nitrogen - Thomas Bjorkman
Insurance Industry Standards Over-estimate Yield Loss Due to Stand Reduction in Processing Sweet Corn - Charlie Rohwer
Combining Lasers and Distress Calls to Control Birds in Sweet Corn - Rebecca Brown
Pea-oat Green Manure and Reduced Nitrogen Rate Delay Maturity of Broccoli But Do Not Reduce Yield - Charlie Rohwer
Field Screening of Cabbage (Brassica oleracea var. capitata) Cultivars for Resistance to Black Rot - Manisha Kumari
Evaluation of Brassica Oleracea Genotypes in Terms of Agronomic Performance - Sotirios Tasioulas
Moderator
MK

Manisha Kumari

Post-Doctoral Research Associate AD, The University of Georgia
Manisha Kumari is a post-doctoral research associate AD at Horticulture department, University of Georgia, Tifton campus, Tifton 31793, GA, USA.
Wednesday September 25, 2024 11:29am - 1:20pm HST
South Pacific 3

11:30am HST

VCM 2 - Effect of Plastic Mulch, Living Mulches and Cover Crops on Soil Characteristics, Weed Pressure and Yield in Organic Glob
Wednesday September 25, 2024 11:30am - 11:40am HST
Standard organic farming production practices for specialty crops frequently involve the use of polyethylene plastic mulch or mechanical soil disturbance to reduce weed competition and enhance crop yields. Although successful, these practices come with environmental consequences, including soil pollution and loss of soil organic matter. As such, alternative methods that prioritize the long-term health of the soil and minimize environmental impact are needed. We performed a field experiment to assess and compare the influence of five soil management systems on soil characteristics, weed pressure and yield in globe artichokes production. Artichoke (Cynara scolymus L.) seedling cvs. Tavor were established on raised beds as: A) intercropped with white clover (Trifolium repens L.) as living mulch, or B) intercropped with crimson clover (Trifolium incarnatum L.) as living mulch, or C) transplanted into mixture of buckwheat (Fagopyrum esculentum M.) and pea (Pisum sativum L.) cover crop residue or D) intercropped with Kurapia (Lippia Nodifera L.) as living mulch, or E) transplanted in PE plastic mulch. Results show that white clover increased soil organic matter (SOM), soil potassium and manganese content, water extractable carbon, soil respiration (CO2), soil nitrate, ammonium and total soil nitrogen compared to plastic mulch at 360 DAS (Days After Seeding). White clover weed suppression ability did not differ from crimson clover and buckwheat/pea mixture. Crimson clover increased SOM at preharvest sampling. Both clovers decreased artichokes yield per plant when compared to plastic mulch. Kurapia increased soil sodium content compared to plastic. Cover crop/reduce tillage system increased SOM at 120 DAS compared to plastic. Due to biomass decomposition, the suppression ability of this mixture decreased over time. Plastic mulch increased copper and iron soil concentration. Artichoke yield from plants grown on plastic mulch had comparable bud weight and yield to buckwheat/pea mixture and Kurapia. The potential to enhance soil nitrogen and carbon levels over a longer period of white clover makes it a valuable choice in systems aiming to improve soil fertility. Crimson clover emerges as the most promising among the clovers, exhibiting less competition compared to white clover, effective weed control, and, although the yield is lower than that achieved with plastic mulch, it maintains a well-balanced crop load. The reduced tillage system has shown promising results, successfully managing weeds adequately and allowing for a satisfactory level of production. No detrimental impact on yield were found intercropping artichokes with Kurapia and, but its effect on soil health was limited.
Speakers
AB

Arianna Bozzolo

Rodale Institute
Co-authors
AS

Andrew Smith

Rodale Institute
NA
JP

Jacob Pecenka

Rodale Institute
NA
Wednesday September 25, 2024 11:30am - 11:40am HST
South Pacific 3

11:30am HST

CHMG 1 - Enhancing Backyard Fruiting Cultivation Efficacy Through Florida-Friendly Landscaping™ Techniques for Homeowners
Wednesday September 25, 2024 11:30am - 11:45am HST
Florida's distinctive subtropical climate renders it a haven for the average backyard gardener. Yet, numerous homeowners grapple with challenges in cultivating dooryard fruits, often due to incorrect planting times or a dearth of expertise. Recognizing this, the University of Florida/Institute of Food & Agricultural Sciences (UF/IFAS) has introduced the Florida-Friendly Landscaping TM program, illuminating nine core principles. These guidelines equip homeowners with the necessary methods and techniques to optimize plant growth and development. As we continue to increase resident population daily from various parts of the world, educating homeowners on these principles, can significantly elevate their chances of realizing their cultivation aspirations.
To meet the persistent demand for edible landscapes, a series of enlightening workshops unfolded across Flagler, Putnam, and Volusia counties. These sessions honed in on sustainable management strategies tailored for cultivating delectable fruits like blackberries, mulberries, goji berries, and citrus varieties. Spanning two to three hours, participants delved into a comprehensive curriculum covering optimal planting and harvest timings, varietal nuances, cultivation methodologies, fertilizer selection, integrated pest management protocols, and the significance of hardiness zones. These workshops roamed through the tri-county region, shining a spotlight on local agricultural enterprises engaged in the production or promotion of sought-after backyard fruits.

This collaborative initiative not only bolstered our overarching educational goals but also catalyzed a surge in agrotourism intrigue. As each program reached its conclusion, attendees departed armed with two plants of their preference and a wealth of resources, poised to lay down the groundwork for thriving cultivation endeavors.
22 Program participants indicated the following as measured via post evaluation survey:
Participants indicated a 73% (n=16) implementation plan for Florida-Friendly Landscaping TM (FFL) principle of "Right Plant Right Place” as they continue in their gardening endeavors.
Participants indicated an 82% (n=18) knowledge gain on cultivar selection, soil testing, and importance of fertilization.
64% (n=14) of program participants shared a plan to continue backyard fruit production using the information disseminated during this program.
Speakers
BC

Brittany Council-Morton

UF/IFAS Volusia County Extension
Co-authors
CJ

Claude Judy Jean

University of Florida
Wednesday September 25, 2024 11:30am - 11:45am HST
South Pacific 2
  Oral presentation (Individual talk), Consumer Horticulture and Master Gardeners
  • SUBJECT Consumer Hort and Master Gardeners
  • Agricultural Sciences (UF/IFAS) 16) implementation plan for Florida-Friendly Landscaping TM (FFL) principle of "Right Plant Right Place” as they continue in their gardening endeavors. Participants indicated an 82% (n=18) knowledge gain on cultivar selection, soil testing, and importance of fertilization. 64% (n=14) of program participants shared a plan to continue backyard fruit production using the information disseminated during this program.

11:30am HST

HSMP 1 - Consumer preference of saffron uses in baked goods and dishes
Wednesday September 25, 2024 11:30am - 11:45am HST
Saffron (Crocus sativus L.) is a perennial cormous crop, possibly originated in Iran, cultivated in the Mediterranean climate region, including Iran, Afghanistan, Spain, Greece, and Kashmir. Due to the labor-intensive harvesting and processing involved, saffron is known as the most expensive spice. Its production has seen a revival in certain regions of the U.S., and Kentucky State University has been evaluating its potential as a niche crop for small and limited-resource farmers in Kentucky since 2019. One objective of this portion of the study was to evaluate consumer preferences for saffron used in various recipes. Two sets of sensory evaluation were conducted with saffron containing cheesecakes and baked goods (i.e., pound cake and short bread). There were three types of cheesecakes (vanilla, lemon, and persimmon) with and without saffron flakes. Overall, test subjects preferred cheesecakes without saffron, with the lemon cheesecake without saffron being the most popular combination. In contrast, participants showed preference for saffron containing recipes over the ones without saffron for the sensory evaluation of both baked goods, especially shortbread. A preliminary test for taste testing was conducted with pound cake to determine the optimal content of saffron. There were three levels of saffron, which was first dissolved in water, and then added to mixture, for both pound cake and shortbread (0, 0.5 and 1.0 tbsp/recipe). The current findings suggest that consumers are favorable of baked goods when saffron is compatible and used in the correct amount and possibly in the correct form.
Speakers
HK

Hideka Kobayashi

Kentucky State University
Co-authors
SC

Sheri Crabtree

Kentucky State University
Wednesday September 25, 2024 11:30am - 11:45am HST
South Pacific 1

11:30am HST

O/LT 1 - The Effects of Mulch Color and Depth on Soil Temperature and Light Transmission
Wednesday September 25, 2024 11:30am - 11:45am HST
Mulching is a common task in the landscape industry, with materials selected to provide environmental benefits (i.e. moderating soil conditions, limiting weed growth) and aesthetic value, with colored mulches often employed to add an artistic element to landscapes. Questions arise over possible effects that mulch color may have on soil temperatures, especially when using darker materials. This research investigated the effects of a commercially available shredded mulch (dyed black, brown, or red) on soil temperature and light transmission in model research plots. A plot at the Hammond Research Station was cleared, graded, and prepared with a typical bed mix comprised of pine bark and sand. A total of 21 sub-plots were prepared, where each sub-plot had a remote temperature sensor buried at the base of the bed mix (8 cm below surface), and a temperature and light sensor placed over top of the bed mix. Mulch was applied to depths of 5 cm or 10 cm directly over the top of the temperature and light sensors, with n=3 for our control (no mulch over the bed mix), red mulch (n=3 for depth of 5 cm and n=3 for depth of 10 cm), brown mulch (n=3 for depth of 5 cm and n=3 for depth of 10 cm), and black mulch (n=3 for depth of 5 cm and n=3 for depth of 10 cm). Soil temperature conditions (both within the mulch itself, and at the base of the bed mix) as well as light transmission through the mulch layer was recorded every 30 minutes throughout a spring and summer season at the Hammond Research Station. Blank (unmulched) plots naturally experienced the most light transmission and temperature extremes. Regardless of mulch color or depth, light transmission was substantially reduced (and often eliminated) equivalently between mulch treatments. Temperature was measured both within the surface mulch layer, and 8 cm below into the subsurface bedding mix. While subsurface temperatures were effectively equivalent between all mulched plots, surface temperatures exhibited substantial differences between mulch colors and depths. Thinner mulch layers experienced more extreme surface temperature fluctuations, with mulch color influencing peak temperatures. The results of this work suggest that different mulch colors and depths have a greater influence on temperature at the immediate surface, but far more muted differences in subsurface temperatures.
Speakers
DA

Damon Abdi

Louisiana State University Agricultural Center
Co-authors
AH

Ashley Hickman

Louisiana State University Agricultural Center Hammond Research Station
NA
JF

Jeb Fields

LSU AgCenter Hammond Research Station
Wednesday September 25, 2024 11:30am - 11:45am HST
Coral 1

11:30am HST

PH 2 - Improving Postharvest Storage and Late-Season Production of Caladium Tubers in Florida Through Chemical Treatments
Wednesday September 25, 2024 11:30am - 11:45am HST
Florida is home to the largest caladium production in the world, supplying essentially all the global caladium tuber demand. These plants are famous for their vibrant leaf colors and patterns and are asexually propagated through tubers. Following plant development, tubers are harvested and stored for a few months before being forced from March to September for potted plant production and direct landscape planting. During extended postharvest storage, caladium tubers risk severe weight loss, tissue decay, and Fusarium tuber rot. The current storage practices under ambient conditions with high temperatures and high relative humidity exacerbate weight loss and tuber rot. The challenges of long-term tuber storage make it difficult to produce pot caladium plants for winter holidays, including Thanksgiving, Christmas, and New Year. These challenges also affect the commercialization of tubers in the Southern Hemisphere during the summer. Opening these marketing opportunities can allow growers to extend and increase their production. Additionally, identifying caladium tubers suitable for late-season production will give Florida growers a competitive advantage. To identify caladium varieties with long-term tuber storage potential and late-season production, 12 varieties were evaluated to target Thanksgiving and Valentine’s Day. No.1-sized tubers were potted in 5-inch containers and grown in a greenhouse. For each variety, 10 tubers were monitored for sprouting and leaf expansion and later evaluated for plant quality using a rating scale from 1 to 5. Potted tubers from all cultivars achieved suitable market quality standards when targeting Thanksgiving, with the higher ratings obtained by cultivars ‘Splash of Wine’, ‘Classic Pink’, and ‘Lemon Blush’. The higher number of leaves and height were obtained by cultivars ‘Classic Pink’, ‘Desert Sunset’, and ‘White Wonder’, and ‘Party Punch’, ‘Ballet Slipper’, and ‘Classic Pink’, respectively. For Valentine’s Day, despite sprouting decreasing, cultivars ‘Splash of Wine’, ‘Hot 2 Trot’, ‘Desert Sunset’, ‘Party Punch’, ‘Classic Pink’, ‘White Wonder’, and ‘Lemon Blush’ reached suitable market quality standards. Overall, the number of leaves and height decreased compared to plants targeting Thanksgiving, however, cultivars with a more desirable number of leaves were ‘Classic Pink’ and ‘Lemon Blush’ whereas cultivars with higher height were ‘Party Punch’ and ‘Ballet Slipper’. Identifying cultivars suitable for late-season production will allow growers to expand their commercialization window for major holidays and to supply tuber demand to the Southern Hemisphere.
Speakers
GC

Gasselle Cordova

University of Florida
Co-authors
ZD

Zhanao Deng

University of Florida
Wednesday September 25, 2024 11:30am - 11:45am HST
Nautilus 1

11:30am HST

UG - The Assessment of Different Growth Mediums for Plug Cultivation in a Controlled Environment
Wednesday September 25, 2024 11:30am - 11:45am HST
Plugs are crucial for starting crop production in greenhouses, soil, and controlled environment agriculture (CEA). Horticultural, vegetable, fruiting, and ornamental crops that utilize plugs for production have demonstrated better plant health, transplant establishment rate, and total yield. Many substances are capable of supporting plug growth, so the APS Laboratory for Sustainable Food at Florida Gulf Coast University investigated the quality of plugs prepared based on different commonly used growth mediums for plug production. We carried out the growth of Rex Butterhead Lettuce Latuca Sativa plugs with six different treatments: 1) Rockwool, 2) Oasis® Horticube, 3) Perlite 4) Coco Coir, 5) Phenolic Foam, and 6) Peat Pellets. The seeds were sowed in their respective growth medium and watered every day. The plugs were then cultivated for 15 days in a controlled environment until two leaves apart from the cotyledon had developed. After 15 days, we collected data which included wet weight (g), dry weight (g), leaf area (cm2), nitrogen content (mg/g), and chlorophyll concentration (mg/cm2). In addition, we derived data including the Leaf Area Index (LAI) and Specific Leaf Area (SLA, cm2/g). Descriptive statistics were used to describe the biomass data. Pairwise permanovas were conducted, followed by pairwise Wilcoxon tests to determine which treatments result in significant differences for each response variable. A permutation MANOVA revealed a significant treatment effect on plug preparation (p=0.001). All subsequent multilevel pairwise comparisons were significant, with the exception of phenolic foam vs perlite (p=0.294). Of all the treatments, we concluded that plugs grown in Peat Pellets produced the most viable plugs with the largest wet weight (g), dry weight (g), and total leaf area (cm2). Results from this study may inform growers about appropriate growth mediums for efficient plug production. Keywords: Controlled Environments, Growth Mediums, Lettuce, Plugs, Urban Agriculture
Speakers
GB

George Buss

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
JL

John L Griffis

Florida Gulf Coast University
NA
KJ

Kathryn Jackson

Independent Researcher
NA
MG

Mya Griffith

Florida Gulf Coast University
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 11:30am - 11:45am HST
Lehua Suite

11:30am HST

WUM 1 - The Impact of Irrigation Rates Based on Crop Water Requirement on Tree Growth and Water Relations in Commercial Citrus G
Wednesday September 25, 2024 11:30am - 11:45am HST
The growing demand for affordable and healthy food to feed the growing population necessitates multilayered strategies to meet food demand and supply features: excessive irrigation application to overcome the impact of erratic rainfall, which imposes pressure on groundwater withdrawals, adversely affecting crop failure and sustainability. The objective of the study was to determine the impact of varying irrigation levels on tree growth, leaf nutrient concentrations, and water relations at selected citrus tree densities. The experiment was carried out on Malabar fine sand (sandy, siliceous, hyperthermic Arenic Alaquods) in a commercial citrus grove near Immokalee, FL, USA from 2019 to 2022. Mature thirteen-year-old ‘Valencia’ (Citrus sinensis) citrus trees grafted on Carrizo (a hybrid of Washington Navel orange and Poncirus trifoliata) planted in tree densities of 360, 485, and US-897 (Citrus reticulata Blanco x Poncirus trifoliata (L.) Raf.) citrus rootstock with 920 trees ha-1. Significant water distribution and movement were detected along the soil profile in response to the irrigation rates with higher volumetric water content on the grower standard highest irrigation. As a result, significant fibrous root length densities (FRLD) and median lifespan were observed in the three-row and two-row experiments with the deficit (50%-crop evapotranspiration, ETc) and moderate (78%-ETc) as compared with the grower standard highest (100%-ETc) irrigation regimes, respectively. Stomata conductance and stem water potential ( manifested less tree water stress when trees received moderate irrigation in the low and moderate tree densities than the highest tree density. This significantly impacted the FRLD in the soil and leaf area index (LAI) above the ground tree growth. Moderate irrigation triggered FRLD and improved root survival probability and lifespan. Meanwhile, nutrient uptake from the soil significantly affected leaf nutrient concentration when trees received moderate irrigation than deficit or highest irrigation rates. As a result, irrigation management improved water relations, leaf nutrient concentration, and tree growth across the varying irrigation regimes.
Speakers
AA

Alisheikh Atta

University of Florida
Alisheikh Atta currently works at the Department of Soil, Water, and Ecosystem Science, University of Florida. Alisheikh does research on HLB-affected citrus nutrient and water management. He studies the impact of plant nutrients on the performance of citrus trees, irrigation water... Read More →
Co-authors
DK

Davie Kadyampakeni

University of Florida
NA
KM

Kelly Morgan

University of Florida
NA
SH

Said Hamido

Rodale Institute
Soil Scientist
Wednesday September 25, 2024 11:30am - 11:45am HST
South Pacific 4

11:30am HST

Dr. Liberty Hyde Bailey's First ASHS Presidential Address
Wednesday September 25, 2024 11:30am - 12:00pm HST
Speakers
Wednesday September 25, 2024 11:30am - 12:00pm HST
Coral 5

11:40am HST

VCM 2 - Effects of Off-Season Winter Cover Crops and In-Season Nematicide Application on Plant-Parasitic Nematodes
Wednesday September 25, 2024 11:40am - 11:50am HST
In the Southeast United States, control of parasitic nematodes in vegetable growing systems has traditionally relied on soil fumigation before planting vegetables. However, new regulations on the application of fumigant pesticides and concerns about their toxicity to non-target organisms are compelling growers to adopt sustainable alternatives. This study examined the effects of winter cover crops and subsequent production of cabbage treated with a non-fumigant nematicide on root-knot (Meloiodgyne incognita) and stubby-root (Nanidorus minor) nematodes. Off-season treatments consisted of oilseed radish cvs. “Control” and “Image”, cereal rye cv. “Wrerens Abrussi”, oat cv. “Tachiibuki”, black oat cv. “Protex” and mustard cv. “Caliente”. In-season treatments consisted of an untreated check and the nematicide fluensulfone, applied through the drip irrigation system one week before transplanting cabbage into raised beds covered with plastic mulch. A weedy fallow treatment was also included for comparison. After growing cover crops and incorporating plant residues into the soil, M. incognita population density was significantly reduced only in plots where Tachiibuki oat was grown. None of the cover crops reduced the population density of N. minor. Nematicide application on cabbage significantly reduced M. incognita populations in plots previously grown with Tachiibuki and Pratex oats, and mustard compared to the untreated check. Similarly, the nematicide reduced the N. minor population density in plots previously grown with oats, mustard, and rye. The efficacy of fluensulfone on root gall severity of cabbage was significant only in the untreated check, with plots previously grown with Image radish having a significantly lower root galling than the mustard, rye, and weedy fallow. Nematicide application reduced root gall severity of cabbage in plots previously grown with radish, Tachiibuki oat, and rye compared to the untreated check. Growing cabbage after cover crops and using the nematicide did not impact cabbage yield compared to the untreated check. These results indicate that cover cropping with Tachiibuki oat and the use of non-fumigant nematicides appear to be effective for managing these nematode species.
Speakers
AH

Abolfazl Hajihassani

University of Florida
Wednesday September 25, 2024 11:40am - 11:50am HST
South Pacific 3

11:44am HST

Fruit Breeding (FRBR)
Wednesday September 25, 2024 11:44am - 12:45pm HST
Haplotype-Phased Genome Assemblies of ‘Sulhyang’ Strawberry (Fragaria ×ananassa) using PacBio Revio Sequencer - Youngjae Oh
Exploring the molecular basis of rootstock-mediated growth vigour in macadamia: Unravelling aquaporin gene dynamics - Pragya Dhakal Poudel
Multivariate Analysis of Fruit Composition Diversity Among the North Carolina Strawberry Germplasm Collection - Gina Fernandez
Improving Blueberry By Dissecting Fruit Texture - juan david jimenez pardo
Assessment of Fruit Composition and its Influence on Flavor and Consumer Preferences in Blackberry - Katelyn Lust-Moore
Sugar Content and Gene Expression Dynamics in Apple Spurs in Response to Fruit Load and Gibberellins - Qiuyi Fu
A Census and The Conservation of Malus coronaria in Michigan - Lily Christian

Moderator
BH

Brianna Haynes

North Carolina State University
Wednesday September 25, 2024 11:44am - 12:45pm HST
Kahili

11:45am HST

FRBR - Haplotype-Phased Genome Assemblies of ‘Sulhyang’ Strawberry (Fragaria ×ananassa) using PacBio Revio Sequencer
Wednesday September 25, 2024 11:45am - 11:55am HST
Cultivated strawberry (Fragaria ×ananassa Duch, 2n = 8× = 56) belongs to the family Rosaceae and is an allo-octoploid species. We report here a high-quality haplotype-phased genome assembly of a representative Korean short-day cultivar, ‘Sulhyang’ using a trio-binning approach. Using PacBio Revio long reads of ‘Sulhyang’ and whole genome paired-end reads (Illumina) of two parents ‘Akihime’, and ‘Yukbo’, we completed telomere-to-telomere phased genome assemblies of both haplotypes. The ‘Sulhyang’ genome was 797 Mb , with a long terminal repeat (LTR) assembly index (LAI) of 17.28. The genome was phased into two haplotypes, phase-1 (784.9 Mb with contig N50 of 12.34) and phase-2 (781 Mb with contig N50 of 16.04 Mb). The BUSCO analysis detected over 99% of conserved genes in the combined phased-1 and phased-2 assembly. Both haploid assemblies were annotated using RNA-Seq data representing various F. ×ananassa tissues from the NCBI sequence read archive, resulting in a total of 104,099 genes in the primary assembly. This haplotype-phased reference genome for ‘Sulhyang’ will broaden our knowledge of strawberry genome evolution and gene functions.
Speakers
YO

Youngjae Oh

Prof., Chungbuk National University
Co-authors
HH

Hyeondae Han

University of Florida/IFAS/Gulf Coast REC
NA
SL

Seonghee Lee

University of Florida/IFAS/Gulf Coast REC
NA
Wednesday September 25, 2024 11:45am - 11:55am HST
Kahili

11:45am HST

O/LT 1 - Subterranean Termite Landscape Mulch Consumption Challenge
Wednesday September 25, 2024 11:45am - 12:00pm HST
Formosan Sub-terranean Termite Landscape Mulch Consumption Payton Floyed1, Edward Bush*2, and Qian Sun1 (1)LSU Department of Entomology and (2)LSU AgCenter, SPESS, Baton Rouge, LA Many landscapers utilize organic mulch substrates composed primarily of wood and bark, making it an ideal food source for the Formosan subterranean termite (Coptotermes formosanus). Formosan termites are one of the most destructive structural pests and recognized as one of the 100 worst invasive species in the world. While foraging, these termites can find and may be able to fully establish colonies in landscaping that uses mulch. The mulch type that attracts the most termites has not been widely investigated and continues to be an issue that needs to be determined. The objective of this research was to measure the biomass consumption by termites. Three C. formosanus colonies were used, two from New Orleans, Louisiana, and one from Gonzales, Louisiana. All were maintained in the laboratory using three total replications per experiment over a 14 d period. Five-hundred total termites (450 workers and 50 soldiers) were placed in each arena (7.5”x10”x4” plastic bin) which used a sand layered bottom for both worker and soldier termites. Each arena was covered with a dark plastic bag to mimic typical subterranean foraging conditions. Mulch particle size distribution and bulk density resulted in expected differences with crushed pine straw having the finest particle size (>50% particle size
Speakers
EB

Edward Bush

LSU AgCenter
Co-authors
QS

Qian Sun

LSU AgCenter
NA
Wednesday September 25, 2024 11:45am - 12:00pm HST
Coral 1

11:45am HST

PH 2 - Impact of Storage Environment on Dormancy Progression and Microbiome of Potato Tubers
Wednesday September 25, 2024 11:45am - 12:00pm HST
Preservation of nutritional and market qualities of potato tubers during postharvest storage is essential for optimum economic return. Protecting tubers from unintended sprouting during storage is one of the major postharvest challenges that potato growers and stakeholders encounter. Storage environment, particularly storage temperature, significantly impacts dormancy progression and sprouting and effect overall marketability. Potato tubers carry significant amount of microbiome in different tissues of tubers from field to storage, which might contribute to overall storage qualities. However, how storage temperature impacts overall potato tuber microbiome and how changes in microbiome influence tuber dormancy are largely unknown. Therefore, the primary objective of this study was to investigate the impact of different storage temperatures on tuber microbiome and monitor the dormancy progression and sprout growth during long-term storage. Certified seed tubers of Russet Burbank were cured after harvest following industry practices. Then, one subset of tubers was stored at constant 8°C, and a second subset was stored at constant 21°C. Three types of tuber tissues (primary meristem, secondary meristem, and tuber flesh) were collected after 4, 8, 12, 17, and 24 weeks of storage for microbiome profiling and sugar and protein analysis. Additionally, a third subset was generated by moving tubers from 8°C to 21°C three days before sampling time of 8, 12, and 17 weeks. Tuber dormancy progression was monitored using additional subsets for each storage condition. As expected, the subset of tubers stored at 8°C had delayed sprouting compare to 21°C, and rapid sprout growth was observed when tubers were moved from 8°C to 21°C. Increase in reducing sugar content was observed in meristem tissues, while it decreased in tuber flesh with progression of storage duration. Interestingly, higher protein content was determined in secondary meristem tissues compare to primary meristems and tuber flesh. Overall, greater bacterial and fungal diversity and abundance were observed in meristem tissues when compared to tuber flesh. Additionally, storage temperatures, storage time, and tuber tissue types significantly impacted tuber microbial profile. In tuber tissues, Ascomycota and Basidiomycota were predominant fungal phyla, while Actinobacteria, Proteobacteria, and Cyanobacteria were the predominant bacterial phyla. Our results suggested that storage temperature and storage duration significantly impact both dormancy progression and tuber microbiome and subsequently contribute to postharvest qualities of potato tubers.
Speakers
MD

Munevver Dogramaci

United States Department of Agriculture
Co-authors
DS

Dipayan Sarkar

United States Department of Agriculture
NA
EF

Evandro Fortini

United States Department of Agriculture
NA
MB

Malick Bill

United States Department of Agriculture
NA
SK

Shyam Kandel

United States Department of Agriculture
NA
Wednesday September 25, 2024 11:45am - 12:00pm HST
Nautilus 1

11:45am HST

UG - Comparative Analysis of Lettuce Growth Using Compost Versus Conventional Soil
Wednesday September 25, 2024 11:45am - 12:00pm HST
Conventional agricultural techniques have been degrading American soils nationwide since the beginnings of modern-day agriculture through practices such as soil tilling, using nitrogen synthetic fertilizers, and monocultural systems. These previously mentioned techniques contribute to degrading soil health, mass emissions of carbon dioxide into the atmosphere, and decreased biodiversity. Regenerative agriculture offers a combination of sustainable practices that will create carbon sinks to sequester atmospheric carbon dioxide, restore national food systems, and prioritize soil health. Regenerative agriculture techniques include the utilization of cover crops, compost, no-tillage, mob grazing, and polyculture. The APS Laboratory for Sustainable Agriculture focused on the effectiveness of compost by comparing the growth of lettuce in four different treatments: 100% compost (100%C), 75% compost 25% Miracle-Gro (75%C-25%MG), 50% compost 50% Miracle-Gro (50%C-50%MG), and finally, 100% Miracle-Gro (100%MG). The lettuce seeds were kept in a growth tent for 15 days during their period of germination before being transferred to four 1x1 meter plots in the Food Forest at Florida Gulf Coast University (FGCU) for the 60-day growth period. The lettuce crops grew to full bloom and ready for harvest. Sampling events took place every six days in which crop growth data including wet weight (g), dry weight (g), chlorophyll concentration (μmol/m^2), and leaf area (cm^2) were collected. Specific Leaf Area (g/cm^2) and Leaf Area Index were derived, and statistical analysis was conducted. Based on the statistical tests conducted at the 5% significance level using R statistical software, soil treatment type was found to be significant (p=0.0002). Soil treatment type was shown to have significantly impacted wet weight (p
Speakers
SH

Sofia Huber

Florida Gulf Coast University
Wednesday September 25, 2024 11:45am - 12:00pm HST
Lehua Suite

11:50am HST

VCM 2 - Lessons Learned from Living Mulch Trials on Midwest Vegetable Farms
Wednesday September 25, 2024 11:50am - 12:00pm HST
In the Great Plains region of the United States, perennial clover living mulch is being explored for the potential benefits of reducing tillage, suppressing weeds, and supplementing soil. Perennial living mulch systems also have the potential to reduce the use of single-use plastic. Research on the use of perennial living mulch in vegetable systems has been limited in the Great Plans, and farmers have expressed interest in trialing this system to improve soil health and reduce erosion by wind and rain. Two vegetable farms, Haroldson Farms in Bruce, SD and Blue Sky Vegetable Company in Worthing, SD, have participated in the on-farm trials since 2023. In collaboration with South Dakota State University, the on-farm trial collaborators were interested in using living mulch to control weeds and reduce the need for plastic. ‘Domino’ white clover (WC) (Trifolium repens), and ‘Dynamite’ red clover (RC) (Trifolium pratense) are the clovers that were selected for the on-farm trials. The clover struggled to grow with the lack of rainfall and was soon overtaken by weeds. Results quickly showed that the lack of moisture had a detrimental effect on the clover’s ability to compete and establish in walkways. A mixture of grasses and broadleaf were observed as the clover declined. Early moisture is essential for the establishment of clover living mulch and be used to its full potential. The planting method of frost seeding would be recommended for future trials to encourage clover germination and establishment before weeds get large enough to compete.
Speakers
CR

Connor Ruen

South Dakota State University
NA
Co-authors
KL

Kristine Lang

South Dakota State University
TN

Thandiwe Nleya

South Dakota State University
NA
Wednesday September 25, 2024 11:50am - 12:00pm HST
South Pacific 3

11:55am HST

FRBR - Exploring the molecular basis of rootstock-mediated growth vigour in macadamia: Unravelling aquaporin gene dynamics
Wednesday September 25, 2024 11:55am - 12:05pm HST
Rootstocks play a crucial role in shaping plant growth and vigour, driven by a complex interplay of physiological, molecular, and genetic factors. Aquaporins (AQPs), as key water transport proteins, are emerging as pivotal component in understanding rootstock-mediated vigour. However, evidence for rootstock effects in macadamia remains limited with no exploration into the mechanisms of rootstock-mediated vigour control, hindering progress in rootstock development for this crop. In this study, we aimed to explore the role of AQPs by conducting a genome-wide investigation on whole genome sequence of Macadamia integrifolia (‘HAES741’). This study identified 37 putative macadamia AQP (miAQP) genes belonging to 5 different sub-families including 11 plasma membrane intrinsic proteins, 10 tonoplast intrinsic proteins, 10 Nod26-like intrinsic proteins, 2 small and basic proteins and 6 X-intrinsic proteins. miAQP genes are unevenly distributed across 11 chromosomes with chromosome 7 possessing the most genes. To investigate the differential expression of plasma membrane intrinsic proteins (PIPs), in high- and low-vigour rootstocks, root, leaf, and stem tissues were collected from trees with a single scion ‘HAES741’ grafted on to 7 different rootstock genotypes . RNA from tissue samples were extracted by a modified CTAB RNA extraction protocol using the Zymo-spin™ IICR Column. RNA quality and quantity was checked via nano spectrophotometer and gel electrophoresis. Primer pairs for 11 PIP genes and 2 housekeeping genes (ACT and EF1b) were designed using Primer BLAST in NCBI. RNA samples were subjected to a real time quantitative RT-PCR. The tissue specific expression data will be analysed to observe differential expressions, if any, between high and low vigour rootstocks and scions. Differential expression patterns reveal the PIP genes associated with vigour control. The correlation between gene expression levels and rootstock vigour provides better understanding on the intrinsic molecular mechanism vigour regulation in macadamia. Moreover, comparative analysis of PIP gene expression between rootstock and scion can provide insights into the rootstock-scion interactions. Overall, results from this study offer a better understanding of the molecular basis of rootstock-mediated vigour control with implications for rootstocks development and orchard optimization in macadamia.
Speakers
PD

Pragya Dhakal Poudel

The University of Queensland
Co-authors
BA

Borhan Ahmed

Bangladesh Jute Research Institute
NA
BT

Bruce Topp

Queensland Alliance for Agriculture and Food Innovation, The University of Queensland
NA
LS

Lindsay Shaw

Queensland Alliance for Agriculture and Food Innovation, The University of Queensland
NA
MA

Mobashwer Alam

Queensland Alliance for Agriculture and Food Innovation, The University of Queensland
NA
Wednesday September 25, 2024 11:55am - 12:05pm HST
Kahili

11:59am HST

Herbs, Spices, and Medicinal Plants - HSMP
Wednesday September 25, 2024 11:59am - 1:10pm HST
Effects of Drought Stress on Secondary Metabolite Production and Yield in Ocimum Basilicum - Daniela Menendez
Effects of Thermal Processing and Drying on Nutritional Quality and Consumer Preference of Amaranthus viridis L. Value-added Product - Megan Reid
Ginseng Growth and Ginsenoside Contents According to Light Intensity - Minhee Kim
Evaluation of anticancer activity of perennial tree seed-derived extracts on various cancer cell lines - Hamin Lee
Exploring the Potential of Annonacin and 2-Deoxy-D-glucose on Non-Small Cell Lung Cancer Cells - Bhoj Raj Bhattarai
Responses and relationship between bioactive compounds and phenotypic traits in Dahurian angelica breeding lines - Eun Jeong Koh
Effects of Foliar Application of Humic Acid and NPK Fertilizers to the Soil on Important Growth Indices of Black Mustard - Keefah Al-Garallaa
Assessment of micropropagated ginger cultivars and generations on plant growth and rhizome yield in a greenhouse - Guochen Yang

Moderator
KA

Keefah AL-Garallaa

Mississippi State University
Wednesday September 25, 2024 11:59am - 1:10pm HST
South Pacific 2

12:00pm HST

HSMP - Effects of Drought Stress on Secondary Metabolite Production and Yield in Ocimum Basilicum
Wednesday September 25, 2024 12:00pm - 12:10pm HST
Climate change makes water stress a more prominent obstacle to maintaining the same yield and quality of harvestable crop biomass for consumers, posing a unique challenge to farmers who must compete for clean water resources with other stakeholders. Thus, farmers must adapt their irrigation strategies to remain profitable and relevant. Basil is a tender perennial crop from the family Lamiaceae that is grown as a culinary herb and as a source of essential oils. Sweet basil (Ocimum basilicum) is a model crop for understanding water stress in economically important crops due to its intolerance to drought stress and its unique phytochemical properties. Sweet basil produces different concentrations of different secondary metabolites in response to abiotic stress, such as eugenol and methyl chavicol. This study seeks to understand what chemical and physical changes occur to sweet basil under water stress within a greenhouse environment. Three different treatments of water stress controlled via drip irrigation and a separate control group were used to analyze the yield and secondary metabolite production within sweet basil. Wet weight, dry weight, height, and phytochemical concentrations were calculated for the different drought treatments. There was a significant relationship between the final height, dry and wet yield, and chemical concentration of the different water stress treatments. One of the most interesting findings of the study was that the high note of sweet basil, a phenylpropanoid known as eugenol, was found in similarly high concentrations throughout the different treatment groups. There were significant differences in concentration across terpenoids such as eucalyptol, germacrene D, and linalool. This study showed that there were significant effects on the yield and concentration of phytochemicals produced by sweet basil from drought stress.
Speakers
DM

Daniela Menendez

Florida International University
Co-authors
DS

Diego Salazar Amoretti

Binghamton University
NA
KJ

Krishnaswamy Jayachandran Jayachandran

Florida International University
NA
MB

Mahadev Bhat

Florida International University
NA
Wednesday September 25, 2024 12:00pm - 12:10pm HST
South Pacific 2

12:00pm HST

VCM 2 - Evaluating Cover Crop Biomass and Roller Crimper Technology for Effective Weed Control in Vegetable Systems
Wednesday September 25, 2024 12:00pm - 12:10pm HST
This study aims to evaluate the efficacy of roller crimper technology in tandem with various cover crop mixtures for weed management in coastal California's vegetable systems. The experiment was conducted at the Rodale Institute California Organic Center (34.220453, -199.108214) in Camarillo, CA. Twenty randomized plots 46 x 12 m were measured and assigned to either to a bare soil treatment or one of two cover crop mixes: oat (Avena sativa) hairy vetch (Vicia villosa), or oat pea (Pisum sativum), with cover crops terminated via conventional tillage using a disk (T) or using a roller crimper for no-till system (NT). Pumpkins (Howden variety) were direct seeded, and data on cover crop growth and weed pressure were collected at three time points: before cover crop termination, after cover crop termination and after harvest. At harvest, a subset of each plot was sampled to count and weigh pumpkins for crop yield assessment. Before termination, the total dry matter of cover crop biomass showed no significant differences between oat/peas and oat/vetch mixes. Oat/vetch exhibited lower weed biomass at 0.74 t/ha compared to oat/peas at 1.98 t/ha (0.8 t/a); bare soil plots had the greatest biomass at 21.35 t/ha. After termination (30 DAT), NT plots showed similar biomass production between oat/peas and oat/vetch. T plots displayed residues on the soil surface, with higher amounts in oat/vetch at 8.7 t/ha compared to oat/peas at 8.4 t/ha. Weed emergence after cover crop termination was comparable across all plots with cover crops, ranging from 1.24 t/ha to 2.22 t/ha, while bare soil exhibited higher weed biomass at 10 t/ha compared to plots with cover crops. After harvest (120 DAT), oat/vetch in NT plots showed greater biomass retention compared to T plots, as did oat/peas in NT plots. All plots experienced biomass reductions, with oat/peas T plots experiencing the most significant decrease at 61.5%. Oat/vetch mixture plots (T and NT) and bare soil had similar pumpkins production per hectare, outperforming oat/pea T plots in terms of fruit number and production per hectare. Oat/pea T plots exhibited decreased fruit weight compared to bare soil.
Speakers
AB

Arianna Bozzolo

Rodale Institute
Co-authors
AS

Andrew Smith

Rodale Institute
NA
JP

Jacob Pecenka

Rodale Institute
NA
Wednesday September 25, 2024 12:00pm - 12:10pm HST
South Pacific 3

12:00pm HST

PH 2 - Strawberry Anthocyanins, Extraction, Assessments and Storage
Wednesday September 25, 2024 12:00pm - 12:15pm HST
The anthocyanin pigments have antioxidant activities and play critical roles in plant and human health. They are abundant in flowers, vegetables, and fruits and are soluble in water, methanol, and nonpolar solvents such as chloroform. Extracting stable pigments with higher concentrations has been the research community's and industries' goal. Spectrophotometric methods can easily measure the total anthocyanin content. Other complex and more expensive methods, such as high-pressure liquid chromatography and ultrasound-assisted methods, are also available to identify and quantify the anthocyanin pigment. Strawberry color affects the appearance, fruit quality after harvest, and consumers' decision-making process. A large group of factors, such as sample type, temperature, pH, solvent type, and the ratio of its components, affect strawberry anthocyanin yield. We studied the effect of some of these variables on the anthocyanin yield, profile, and color of strawberries. Extraction solvents significantly changed the anthocyanin yield. The results suggest that acidified chloroform-methanol extracted the highest anthocyanin content compared to water-based solvents. Methanol-water-based solvents also performed better than water alone. Processing time (incubation time) was lowest in the pH differential method; however, the haze produced in this method may interfere with the spectrophotometry. Chloroform-methanol solvent with higher pH extracted pelargonidin as the main anthocyanin, and methanol and water-based solvents extracted delphinidin in UHPLC. Chloroform extracts reduced the redness and increased the extracts' brightness mainly due to higher pelargonidin content. Less redness and increased brightness indicated some level of color degradation of the extracts after storage for 48h at 4 °C.
Speakers
Wednesday September 25, 2024 12:00pm - 12:15pm HST
Nautilus 1

12:00pm HST

UG - Feasibility of Plug Production Utilizing Digestate From Home Water-Energy-Food Systems (H-WEF)
Wednesday September 25, 2024 12:00pm - 12:15pm HST
The integration of sustainable technologies in waste management systems has become imperative in addressing the escalating challenges of agricultural productivity and sustainability. Plugs are essential when starting crop production in controlled environment agriculture (CEA) setups and greenhouses. Horticultural crops such as vegetables, fruiting, and ornamental plants that utilize plugs have demonstrated higher success rates, healthier plants, and higher total yields. The APS Laboratory for Sustainable Agriculture at explored the innovative utilization of digestate from the Home Water-Energy-Food Systems (H-WEF), the H-WEF system converts household food waste into biogas, electricity, and nutrient-rich digestate. The digestate from the H-WEF system was used to produce agricultural plugs, presenting a novel approach to circular resource utilization. We carried out the growth of Rex Butterhead Lettuce Latuca Sativa plugs with eight different treatments, 1) control synthetic fertilizer; 2) 5% Digestate – 95% RO Water (5D–95RO); 3) 10% Digestate – 90% RO Water (10D–90RO); 4) 15% Digestate – 85% RO Water (15D–85RO); 5) 20% Digestate – 80% RO Water (20D–80RO); 6) 25% Digestate – 75% RO Water (25D–75RO); 7) 30% Digestate – 70% RO Water (30D–70RO); 8) 35% Digestate – 65% RO Water (35D–65RO). The seeds were sowed with their fertigation treatment and watered every day. The plugs were cultivated for 15 days in a controlled environment until two leaves had developed after the cotyledon. After 15 days, we collected data on wet weight (g), plug head area (cm2), total leaf area (cm2), total nitrogen content (mg/g), total chlorophyll content (mg/cm2), and dry weight (g). In addition, we collected data on the Leaf Area Index (LAI, cm2/cm2) and Specific Leaf Area (SLA, cm2/g). The synthetic fertigation yielded a higher wet weight than the following treatments: 5D–95RO, 10D–90RO, and 35D–65RO. While the 30D–70RO treatment produced a larger plug head than all other treatments. The digestate-based fertilizers were comparable to the synthetic fertilizer at dilutions of 25D–75RO and 30D–70RO. Results from this study may inform growers about the viability of utilizing digestate for plug production.
Speakers
RD

Rory Dunn

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
JG

John Griffis

Florida Gulf Coast University
NA
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
ST

Seneshaw Tsegaye

Florida Gulf Coast University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 12:00pm - 12:15pm HST
Lehua Suite

12:00pm HST

Come work with Driscoll’s Global R&D Team
Wednesday September 25, 2024 12:00pm - 12:30pm HST
Come to the Hort Theater to hear about exciting job opportunities with Driscoll’s, the global leader in fresh market berries! You’ll hear an overview of our business operations and locations as well as the types of roles we hire for and what we look for in prospective candidates. You may even hear a few tips and tricks to help get your application noticed that you can use with us – or other prospective employers. Please join for an informal presentation and short Q&A session.
Speakers
LM

Logan McCollum

Senior Recruiter, Driscoll's
Wednesday September 25, 2024 12:00pm - 12:30pm HST
Coral 5

12:00pm HST

Technology Applications in Horticulture (TECH) Interest Group Meeting
Wednesday September 25, 2024 12:00pm - 12:30pm HST
Moderator
Wednesday September 25, 2024 12:00pm - 12:30pm HST
Sea Pearl 3

12:00pm HST

International Division Luncheon
Wednesday September 25, 2024 12:00pm - 2:00pm HST
Advance ticket purchase required.

Speaker: Dr. Wagner Vendrame, Interim Chair & Professor, Ornamental Horticulture and Biotechnology. University of Florida
International Strategies in Horticulture
Internationalization of the curriculum and research programs in horticulture has become increasingly important to us in higher education. For students, exposing them to different cultures brings a better understanding of horticultural markets and activities, unique cultural experiences, and a broader view of global issues related to agriculture. For researchers, adding an international component to your program is essential for promotion, while also bringing opportunities for collaboration and increased funding. In this presentation, I will share my international experience and discuss different strategies for internationalization of research and academic programs.
 
Dr. Vendrame leads a broad research program focusing on production and conservation of ornamental plants using plant tissue culture and cryopreservation techniques, including orchids, ornamental trees, foliage plants, palms, and other ornamental plants. In 2007, he partnered with NASA on an innovative research project to evaluate the growth, development and differential gene expression in plant cells of jatropha (Jatropha curcas), a biofuel species, as affected by microgravity, with five spaceflight studies on board of the space shuttles Atlantis, Endeavour and Discovery, and the International Space Station National Laboratory. More recently, studies have focused on cryopreservation of orchid seeds, protocorms and pollen, palm seeds, and banana in vitro shoots; and large scale propagation of plants using temporary immersion bioreactor technology, including micropropagation of orchids, bromeliads, sugarcane, banana, papaya, palms, and caçari (a tree native to the Amazon rich in vitamin C).

Moderator
LL

Leonardo Lombardini

ASHS International Division VP
Speakers
avatar for Wagner Vendrame

Wagner Vendrame

Professor & Interim Department Chair, University of Florida
Wednesday September 25, 2024 12:00pm - 2:00pm HST
Hibiscus 1

12:05pm HST

FRBR - Multivariate Analysis of Fruit Composition Diversity Among the North Carolina Strawberry Germplasm Collection
Wednesday September 25, 2024 12:05pm - 12:15pm HST
Strawberries are a highly sought-after fruit for their flavor, color, and nutritional benefits. In this study, strawberry fruit from 268 commercial cultivars and advanced selections from the North Carolina breeding program were evaluated to determine and characterize genotype diversity, relationships, and overall trends in fruit composition. Fifteen marketable, fully red, firm fruit were harvested per genotype between April and June of 2022 from a greenhouse core collection and held at -20°C until analysis. Juice from thawed fruit was used to collect total soluble solids (SSC), total titratable acidity (TTA), and pH data. Strawberry juice was also extracted with acidified methanol (0.1ml/1.6 ml total) and supernatants used to determine monomeric anthocyanin content (TA) using the pH differential method. Agglomerative hierarchical clustering (AHC) and multivariate analysis of variance (MANOVA) sorted genotypes into four clusters, highlighting significant differences in fruit composition profiles. The majority of commercial cultivars, and 38 advanced selections, were grouped together in Cluster 1. This cluster was distinguished by lowest SSC (7.0%), TTA (0.72%), and TA (31.22 mg/100g) values. In contrast, Cluster 2 containing 41.4% of germplasm had fruit highest in TA (54.57 mg/100g). Fruit from genotypes in Cluster 3 had high pH and %SSC, and the smallest group (Cluster 4), with 13.1% of the germplasm, had low pH and was significantly greater in %TTA. Regional strawberry breeding programs were found to group together. The Florida germplasm were grouped in Cluster 1, North Carolina commercial genotypes in Cluster 2, and two advanced New Jersey genotypic lines were found in Cluster 3. California day-neutrals were found in Cluster 1, while short-day genotypes were split between the first two clusters. Additionally, the first two principal components in PCA analysis captured 64.88% of the total variance, with both pH and TTA largely contributing to PC1 (91.1%), SSC in PC2 (71.1%), and TA associated with PC3 (77.4%). Variation in pH and %TTA had a more pronounced effect on genotype profiles and were the primary driving force for germplasm separation and differentiation. This work represents the first instance where an entire germplasm collection was assessed together in a single evaluation. The determination of genotype diversity, characterization of relationships among the genotypes and the fruit composition parameters, and visualization of trends within the collection will help guide future breeding decisions for developing new strawberry cultivars with improved quality.
Speakers
avatar for Gina Fernandez

Gina Fernandez

North Carolina State University
NA
Co-authors
BH

Brianna Haynes

North Carolina State University
PP

Penelope Perkins

North Carolina State University
NA
Wednesday September 25, 2024 12:05pm - 12:15pm HST
Kahili

12:10pm HST

HSMP - Effects of Thermal Processing and Drying on Nutritional Quality and Consumer Preference of Amaranthus viridis L. Value-added Product
Wednesday September 25, 2024 12:10pm - 12:20pm HST
Economic opportunities have arisen to increase the production of specialty crops catering to ethnically diverse consumers. Opportunities to capture anticipated niche market growth for ethnic crops continue to grow. Amaranthus viridis L. (amaranth), a highly nutritious leafy vegetable, eaten cooked or raw, with a nutritional value similar to spinach, is widely cultivated, highly nutritious, and has medicinal properties. Studies were conducted to 1) evaluate two thermo-processing (steam and water blanching) and three drying methods (freeze, hot air, and infrared drying) for the development of amaranth value-added products and 2) analyze the effective thermo-processing and drying methods to maximize the phytonutrient contents and minerals in the vegetable. Two thermo-treatments, steam blanch (SB) and hot water (HB), and the control (C), three drying treatments, freeze-dried (FD), hot air dried (HAD), and infrared dried (ID) were used. The treatments were T1:FD(C), T2:HAD(C), T3:ID(C), T4:FD(SB), T5:HAD(SB), T6:ID(SB), T7: FD(HW), T8: HAD(HW), T9: ID(HW). Amaranth was harvested once per week and processed three times throughout the growing season (1st harvest (28 days after transplanting (DAT)), 2nd harvest (56 DAT) in the middle of the growing season, and the 3rd harvest (84 DAT) at the end of the growing season). Phytonutrients, ascorbic acid and β-carotene, rehydration capacity, and sensory evaluation were analyzed. Significant differences in phytonutrients (total phenolic content (TPC) and total flavonoid content (TFC)) were observed among treatments and harvest times, with the FD(C) treatment being significantly higher in TPC and TFC during the 1st and 2nd harvest when compared to the other treatments. Ascorbic acid was significantly higher in FD(C) and HAD(C) (419.33 mg/100g, dm and 203.3 mg/100g, dm, respectively). ID(C), ID(SB), ID(HW) and HAD(SB) were significantly lower in ascorbic acid when compared to the other treatments. Significant differences were also observed in β-carotene among treatments. For rehydration capacity, rehydration at 9 minutes showed the highest water absorbance for all treatments, with FD(C) and HAD(C) being significantly higher, while HAD(HW) and ID(HW) were significantly lower in water absorbance for the rehydration times of 3, 6 and 9 minutes. For the sensory evaluation, 59%, 73%, and 54% of respondents indicated that the rehydrated samples were just right for flavor, color, and texture, respectively; and 45% of respondents indicated that the overall quality of the rehydrated sample was good. This study provides valuable insights for the development of value-added products catering to ethnically diverse consumers.
Speakers
MR

MEGAN REID

University of Maryland Eastern Shore
Co-authors
BM

Byungrok Min

University of Maryland Eastern Shore
NA
CN

Caleb Nindo

University of Maryland Eastern Shore
NA
CC

Corrie Cotton

University of Maryland Eastern Shore
Wednesday September 25, 2024 12:10pm - 12:20pm HST
South Pacific 2

12:10pm HST

VCM 2 - Fall Cover Crops to Follow Carrot Harvest on High Organic Matter Soils
Wednesday September 25, 2024 12:10pm - 12:20pm HST
The high organic matter (muck) soils in the Holland Marsh, Ontario, Canada, are prone to wind erosion, especially in the fall and winter months. Good canopy coverage of ideally 30%, is important for protecting the soil and reducing soil erosion. Carrots are usually harvested in October. Cool temperatures at this time result in slow germination and growth of cover crop species. Field trials were conducted to assess the efficacy of various cover crops and methods for rapid establishment after carrot harvest. One approach to increasing germination and emergence is seed priming. Seeds of barley, oats, and triticale were primed by soaking for 24 hr in water (hydro-priming) or potassium nitrate at 5 mg L-1 (osmo-priming). Seed was dried for 24 hours and then seeded into pots placed in controlled environments at 5, 10 or 21°C. Priming generally resulted in faster germination and higher biomass especially at lower temperatures of 5 and 10°C. Primed and non-primed seed was seeded into high organic matter soil (50% organic matter, pH 6.9) on 17 Oct. and crop growth was assessed on 13 Nov. There were no advantages of priming in the field trials. Non-primed barley had high or higher canopy coverage (13%), plant counts and dry weight, compared to other species and primed seed. Barely was also grown as transplants with 2 seeds/plug and transplanted in the trial on 17 Oct. This treatment had higher canopy coverage (25%) and dry weight than seeded treatments. However, using barley transplants is not a cost effective option at this time. In a separate trial on an adjacent site, barley was over-seeded into standing carrots on 27 Sept. at 200 kg ha-1, and the carrots were harvested on 17 Oct. Barley and fall rye were direct seeded on 17 Oct. Pre-harvest seeding of barley resulted in significantly better establishment, canopy coverage and biomass, although all were low, maximum 12% coverage. There was a strong positive correlation between canopy coverage and biomass production across all trials. More research is needed on cover crops species and establishment methods.
Speakers
MR

Mary Ruth McDonald

University of Guelph
Co-authors
KS

Kimberly Schneider

University of Guelph
NA
NP

Neem Pandey

University of Guelph
NA
Wednesday September 25, 2024 12:10pm - 12:20pm HST
South Pacific 3

12:14pm HST

Plant Biotechnology 2 (PB 2)
Wednesday September 25, 2024 12:14pm - 12:29pm HST
New insights into the Yellow2 locus and its role in beta-carotene accumulation in carrots (Daucus carota) - Michael Paulsmeyer
Overexpression of the Coding Sequence of Ma1 Leads to Enhanced Anthocyanin Biosynthesis in Apple via MYB73. - Mengxia Zhang
Rapid Detection and Coinfection Analysis of Aspergillus flavus in Peanut SeedsRapid Detection and Coinfection Analysis of Aspergillus flavus in Peanut Seeds - Emran Ali
RNA-seq Analysis Reveals Differentially Expressed Genes in Sweetpotato cv. Beauregard under Lead Stress - Mary Ann Munda
RNASeq Analysis Reveals Key Pathways Involved in Low Nitrogen Tolerance at the Onset of Storage Root Formation in Sweetpotato cv Bayou Belle - Lisa Arce
Introducing CHiDO – a No Code Genomic Prediction Software implementation for the Characterization & Integration of Driven Omics - Diego Jarquin
Moderator
Wednesday September 25, 2024 12:14pm - 12:29pm HST
South Pacific 4

12:14pm HST

Local Food Systems (LOCSY)
Wednesday September 25, 2024 12:14pm - 1:45pm HST
Exploring Markets for Horticultural Food Crops in Midwestern United States - Linda Prokopy
An expanded scope of ethnic crops research and outreach in the United States: implications on immigration and urban food - Fernanda Krupek
Youth Sustainable Agriculture Urban Farming Entrepreneurship Program: An Overview and Pilot Results from Urban Farming - Kathryn Orvis
Connecting the Dots: Creating School Garden and Produce Taste Testing Programs in Kentucky - Cindy Finneseth
Garden to Pantry: An Interactive and Interdisciplinary Approach to Growing and Preserving Produce - Rebecca Catalena
Fermented Hot Pepper Sauce as a Model for New Value-Added Opportunities for Local Food Production - Matthew Behrends
The Missouri Produce Growers Video Newsletter – Digestible, Accessible and Impactful Extension Education - Justin Keay
The Center for Sustainability of Farms and Families: Impacts of The Small Scale Farm Grant on Local Foods in Kentucky - Joni Nelson
The Waimānalo Learning Center: Land-Grant Experiment Stations as a Space to Heighten Community Engagement and Advancement - Ilima Ho-Lastimosa

Moderator
KO

Kathryn Orvis

Professor, Purdue Univ
Wednesday September 25, 2024 12:14pm - 1:45pm HST
South Pacific 1

12:15pm HST

FRBR - Assessment of Fruit Composition and its Influence on Flavor and Consumer Preferences in Blackberry
Wednesday September 25, 2024 12:15pm - 12:25pm HST
Breeding efforts to improve blackberry (Rubus subgenus Rubus) flavor have previously been a subjective and imprecise process. The flavor perception of blackberries is largely controlled by interactions between sugars, acids, and volatile components. The aim of this study was to determine what combinations of these biochemical compounds result in positive flavor perception by the average consumer to assist in determining breeding targets. In the first year of data collection, consumer panelists assessed pureed frozen blackberries from the University of Arkansas Fruit Breeding Program for overall liking, aroma, flavor, sweetness and sourness across 24 sensory panels. Pearson correlation coefficients were generated to determine the relationship between overall liking and significant effects. Positive correlations to overall liking were significant for flavor intensity (0.99), aroma intensity (0.50), and sweetness intensity (0.89) indicating increases in flavor, aroma, and sweetness resulted in greater liking. Sourness was found to have a negative correlation with overall liking (-0.81). The positive correlation between liking and Brix (0.54) aligns with the perceived sweetness relationship, similarly the negative relationship between liking and titratable acidity (-0.59) aligns with perceived sourness. Panelists’ perceptions of fruity or indulgent flavors such as grape, banana, strawberry, apple, jam and candy produced significant positive correlations with overall liking. While fruit presenting flavors described as citrus, grassy, earthy, musty, pine, or chemical produced significant negative correlations with overall liking. The volatiles associated with these perceived flavors were also assessed using gas chromatography mass spectrometry.
Speakers
KL

Katelyn Lust-Moore

University of Arkansas
Co-authors
JL

Jackie Lee

University of Arkansas
NA
MW

Margaret Worthington

University of Arkansas
NA
RT

Renee Threlfall

University of Arkansas
NA
SF

Samuel Fernandes

University of Arkansas
NA
SL

Scott Lafontaine

University of Arkansas
NA
Wednesday September 25, 2024 12:15pm - 12:25pm HST
Kahili

12:15pm HST

LOCSY - Exploring Markets for Horticultural Food Crops in Midwestern United States
Wednesday September 25, 2024 12:15pm - 12:25pm HST
Agricultural communities in the Midwest face ongoing economic, environmental, and social challenges. A variety of research shows that increasing diversity in an agricultural system can help overcome these challenges. The Diverse Corn Belt (DCB) is a USDA-NIFA funded project focuses on developing an evidence-based framework and vision of how to enable a more diverse agricultural landscape across the Corn Belt (Illinois, Iowa, and Indiana). This interdisciplinary project is exploring and promoting diversity at the farm, landscape, and market levels through Research, Extension, and Education. We have completed 18 focus groups across Indiana, Illinois and Iowa with conventional and diversified farmers, interviews with horticultural growers, and surveys of retailers, processors, and consumers. Last year we presented results from focus groups and interviews. This year, we add results from survey findings to highlight gaps between different stakeholders in the horticultural value chain, as well as the most valuable food labels among consumers, retailers, and processors.
Speakers
LP

Linda Prokopy

Purdue University
Co-authors
AT

Ariana Torres

Purdue University
NA
Wednesday September 25, 2024 12:15pm - 12:25pm HST
South Pacific 1

12:15pm HST

PB 2 - New insights into the Yellow2 locus and its role in beta-carotene accumulation in carrots (Daucus carota)
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Carrots (Daucus carota) are a unique model for the accumulation of carotenoids. Beta-carotene accumulates in large amounts in the taproot if the proper alleles of the following three loci are present: OR, Y, and Y2. These three loci are not carotenoid biosynthetic genes but rather post-transcriptional regulation of carotenoid accumulation. The genes underlying the OR and Y loci have been characterized, but the gene underlying the Y2 locus is unknown. Through genomic and transcriptomic analyses, a single candidate that may interact with light signaling was found. To determine the function of this gene, the functional transcript from wild carrot was overexpressed in orange carrots and used in a transient infiltration assay with a GFP fusion tag in tobacco. The orange allele of this gene has a large transposon insertion that theoretically inactivates the gene. However, full length transcript can still be detected in orange carrots. This begs the question of whether the transposon is still active in certain accessions. In this study, the proportion properly assembled Y2 transcript was analyzed via qRT-PCR. A KASP marker was also developed to assist plant breeders in selection for the Y2 locus.
Speakers Co-authors
PS

Philipp Simon

USDA-ARS
NA
Wednesday September 25, 2024 12:15pm - 12:30pm HST
South Pacific 4

12:15pm HST

PH 2 - Isolation of Pathogenic Strain of Trichoderma atroviride from Symptomless, Disease-Free Sweetpotato (Ipomoea batatas L.) Storage Roots.
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Many fungal endophytes have the ability to promote plant growth, as well as increase the host plant’s tolerance to abiotic and biotic stresses. Most endophytic species of Trichoderma are well known biocontrol agents and have been used to control diseases caused by phytopathogens of the genera Rhizoctonia, Fusarium, and Phytophthora. However, our recent research has isolated a strain of Trichoderma from sweetpotato storage roots purchased from a local farm, which was shown to develop root rot symptoms. Therefore, the objective of this project was to evaluate this isolate, especially for its potentially pathogenic nature. In the laboratory, the ITS region of the isolate was amplified, and gene sequencing placed it to T. atroviride with 99% homology. However, T. atroviride has never been identified as a disease-causing agent for sweetpotato in literature so far. Pathogenicity test was carried out accordingly, by inoculating this isolate onto healthy, symptomless sweetpotato storage roots. Two weeks post-inoculation, the storage roots were cut in half to reveal necrotic lesion development between 1.7 and 2.1cm in diameter based on three replications. The necrotic tissue was sampled and cultured on PDA, and the re-isolated fungal specimen was confirmed to be T. atroviride through gene sequencing. This result demonstrated that under environmental conditions conducive for pathogen development, this strain of T. atroviride is capable of causing root rot disease in sweetpotatoes. This finding is particularly significant as farmers typically store sweetpotatoes for an extended time, sometimes up to a year, which increases the possibilities for disease occurrence. Dual-culture assays are still ongoing to determine if this strain of T. atroviride could be a beneficial endophyte under different storage conditions, especially when other fungal endophytes are co-existing in the same storage root.
Speakers
RN

Richard Noel Torres

University of Missouri - Columbia
Co-authors
JS

James Schoelz

University of Missouri - Columbia
NA
PT

Peng Tian

University of Missouri - Columbia
NA
XX

Xi Xiong

University of Missouri - Columbia
NA
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Nautilus 1

12:15pm HST

UG - From Flower to Fruit: Growing Degree Days and Peach Ripening
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Anticipating crop advancement, particularly fruit maturation, is critical for peach growers' success and marketing. Growing Degree Days (GDD) predict the growth and development stages of plants and insects. They are based on the accumulation of heat units above a specific baseline temperature, under the concept that a certain amount of heat is needed to develop from one stage to another in the life cycle. GDDs are used for various purposes in agriculture and horticulture, such as planting scheduling, pest management and crop monitoring. Peach growers use GDD to predict the peach cultivar maturity and schedule harvesting. However, peach cultivars' ripening time is reported in the calendar or Julian days (JD) or as the number of days before or after a reference cultivar, which is not amenable to climate change. Therefore, we modeled GDD in a diverse set of peach and nectarine cultivars and breeding accessions using the Baskerville-Emin (BE) method. The GDD was calculated from full bloom to fruit maturity using historical temperature, bloom and ripening data collected at the Musser Fruit Research Station in Seneca, South Carolina, in the 2017-2023 period. GDD and JD variability will be presented, and implication of providing GDD information on existing and newly released cultivars for producers and researchers will be discussed.
Speakers
MA

Matthew Almy

Clemson University
NA
Co-authors
JM

John Mark Lawton

Clemson University
NA
KG

Ksenija Gasic

Clemson University
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Lehua Suite

12:19pm HST

Growth Chambers and Controlled Environments - (CE)
Wednesday September 25, 2024 12:19pm - 1:40pm HST
Urban Agriculture Efficiency: A Year-Long Evaluation of Kale Yield and Energy Use in a Shipping Container Farm - Skyler Brazel
Precise Moisture Control Promotes Optimal, Fast, and Uniform Spinach Seed Germination - Shem Msabila
Production of Red Leaf Lettuce at Vertical Farm Equipped with Blue LED According to Anthocyanin Concentration and Its Gene Analysis - Junjira Satitmunnaithum
Interlighting Improves Tomato Yield in Northern Greenhouses - Meriam Karlsson
Assessing the Impact of UV-C Treatment on Growth Parameters and Nutrient Levels in Hydroponic Systems for Romaine Lettuce Cultivation - Markanna Moore
Effect of low root-zone temperature and UV radiation on growth and gene expression of secondary metabolite pathways in Nicotiana benthamiana - KiHo Son
Effects of Short-Wavelength UV-B, UV-A, and Blue Light on the Rose Flower Color Transition Phenotype - Navdeep Kaur
Arduino Uno Can Reliably Log Substrate Moisture from a Bus of Digital Sensors and Control a Drip-Irrigation System - Stephanie E Burnett
Precise Moisture Control Promotes Optimal, Fast, and Uniform Spinach Seed Germination - Shem Msabila
Moderator
SB

Skyler Brazel

University of Tennessee - Knoxville
Wednesday September 25, 2024 12:19pm - 1:40pm HST
Coral 1

12:20pm HST

CE - Urban Agriculture Efficiency: A Year-Long Evaluation of Kale Yield and Energy Use in a Shipping Container Farm
Wednesday September 25, 2024 12:20pm - 12:30pm HST
Urban expansion is a threat to agricultural land. As cities increase in size and residential areas are being built on arable land, a new solution to growing food in urban area needs to be considered. Shipping container farms are designed to grow a high number of plants in a small area. These farms are programmable to fit the environmental parameters that are optimal for each type of crop. In this experiment, ‘Toscano’ kale was grown inside the farm and harvested weekly for one year to simulate farm production. The average day/night temperature in the farm was 22.8C and 15.6C with a photoperiod of 20 hours. Sole sourced lighting was supplied by light emitting diodes with an 80:20 red:blue ratio and an intensity of 100 mol . m -2. s -1 for a daily light integral of 7.2 mol . d -1 . Electrical energy use of the farm was collected on three categories of energy usage: Lighting, HVAC, and all Other Energy usage. Seeds were sown four weeks prior to transplant. Plants were transplanted weekly into vertical channels and harvested 12 weeks after sowing. This experiment was a complete block design with block nested in time. Yield data was collected at time of harvest, including plant number, fresh mass, dry mass, plant height, canopy area, and leaf number. The mean number of plants per replication was 320. The mean fresh mass per plant by block was 43.34g, 48.84g, 53.17g, 59.15g, 57.88g, and 53.29g, respectively, while mean dry mass was 3.31g, 3.66g, 3.94g, 4.42g, 4.3g, and 4.08g, respectively. Daily mean lighting and other energy consumption exhibited no variation across all 48 harvests. Daily mean HVAC energy consumption varied based on outdoor environmental conditions, with increased usage during summer months and a maximum of 33.53 kWh/day. Overall, fluctuations across mean fresh mass needs to be investigated further as the optimal harvest date for this farm may occur prior to 12 weeks, for both plant yield and energy consumption levels.
Speakers
SB

Skyler Brazel

University of Tennessee - Knoxville
Co-authors
CS

Carl Sams

University of Tennessee
KR

Katelynn Rector

University of Tennessee - Knoxville
NA
Wednesday September 25, 2024 12:20pm - 12:30pm HST
Coral 1

12:20pm HST

HSMP - Ginseng Growth and Ginsenoside Contents According to Light Intensity
Wednesday September 25, 2024 12:20pm - 12:30pm HST
Ginseng (Panax ginseng C.A. Meyer) is mainly cultivated in the Republic of Korea and China, and has been traditionally used as a medicinal plant in East Asia for the treatment of diseases such as hypertension, diabetes mellitus, liver and kidney dysfunction, mental disorders, and skin inflammation. Ginseng roots are cultivated after maturing at 3 to 6 years of age. The harvested ginseng roots are consumed and sold in various forms of products, such as fresh ginseng, red ginseng, and white ginseng. Ginseng is a shade-tolerant crop and requires shading facilities. It grows well with a light intensity of 10%, but its growth is hindered at light intensity above 20% due to high temperature. Therefore, it is cultivated with a light intensity set to 10% from April to October and harvested in October. However, if early harvesting is done in August to increase farm income, growth is low due to insufficient light. Therefore, a cultivation experiment was conducted with the light intensity set to 10% and 20% for the August harvest, and the yield and ginsenoside contents were compared with the October harvest. The yield of the 20% light intensity treatment group was 665 kg/10a, whereas the yield of the 10% light intensity treatment group was 572 kg/10a. The yield of the 20% treatment group was 16.3% higher than that of the 10% treatment group. According to the analysis on nine ginsenoside components including Rg1, the total ginsenoside contents in the 20% light intensity treatment group was 27.51 mg/g, which was 75.3% higher than that of the 10% light intensity treatment group at 15.69 mg/g. Specifically, Rg1, Re, Rb1, and Rc were 3.40, 7.29, 7.93, and 3.84 mg/g, respectively, more than twice as high as those in the 10% light intensity treatment group. Conclusively, a light intensity of 20% was determined to be optimal for maximizing ginsenoside cultivation for August harvesting.
Speakers
MK

Minhee Kim

South Korea, Ginseng&Medicinal Plant Research Institute, Chungcheongnam-do Agricultural Research and Extension Services
Co-authors
KS

Ka Soon Lee

Ginseng
NA
SI

Sun Ick Kim

Ginseng
NA
Wednesday September 25, 2024 12:20pm - 12:30pm HST
South Pacific 2

12:20pm HST

VCM 2 - Cover Crops For Vegetable Research Farms Need Nitrogen
Wednesday September 25, 2024 12:20pm - 12:30pm HST
On research farms on which vegetable crops are studied, there is often a need to aggressively maintain and improve soil health, while also keeping fields ready to be assigned to research projects. We tested a protocol for keeping a Northeast farm in an appropriate condition by alternating a winter cover crop of cereal rye and a summer cover crop of forage sorghum-sudangrass with no tillage. The alternating cycle was flexible for entry points when vegetable researchers finished with an experiment, as well as for exit points to make the ground ready for an experiment. Rye was sown in late September in Geneva, NY with a no-till drill and allowed to grow to anthesis in May. Sorghum-sudangrass was sown in mid-June with the no-till drill. We tested how much nitrogen fertilizer was needed to obtain a desirable amount of growth (3 tons/acre dry mater) in the sorghum- sudangrass. The trial was done in four fields using 0, 20, 40 and 60 lb N broadcast on the rye residue at planting. The highest rate is as much as our farm would agree to invest in a cover crop, but also below forage-crop recommendations. The biomass when growth stopped due to cold (Sept 18) responded strongly to nitrogen. Without nitrogen, the biomass was only 0.5 T/ac. At 60 lb/ac, the biomass ranged among fields from 2 to 4 T/ac. Nitrogen limitation was also assessed using a SPAD chlorophyll meter. The leaves in the 0, 20 and 40 lb/ac were yellow (SPAD 22-28), with the top N rate notably greener (SPAD 30-35). The fully green control had a SPAD value of 40. The cover crop rotation kept the field in a condition where is could be prepared to being a research project with about a month’s advance notice. However, to get sufficient growth of the summer cover crop, additional nitrogen is needed. This farm is on a high-fertility silt loam, but with low organic matter from repeated research trials. In that situation, at least 60 lb/ac of actual N is needed for the cover crops to meet biomass expectations.
Speakers
TB

Thomas Bjorkman

Professor, CALS Horticulture
Wednesday September 25, 2024 12:20pm - 12:30pm HST
South Pacific 3

12:25pm HST

FRBR - Improving Blueberry By Dissecting Fruit Texture
Wednesday September 25, 2024 12:25pm - 12:35pm HST
Blueberry texture is a critical trait impacting mechanical harvesting, transportation resilience, shelf life, and consumer preference. Its complexity arises from multiple attributes, requiring a depth understanding for developing breeding tools to generate varieties with superior texture profiles. In this study, a diverse group of southern highbush blueberry (SHB) genotypes, reflecting various textures, were subjected to mechanical phenotyping, consumer perception analysis, and cell wall composition analysis. By conducting instrumental analysis using a texture analyzer, three key parameters crucial for genotype differentiation based on texture were identified. Consumer perception analysis revealed moderate agreement in texture classification between breeders and panelists. Additionally, cell wall composition analysis highlighted galacturonic acid as a potential monosaccharide capable of categorizing texture. The integration of mechanical phenotyping, consumer perception analysis, and cell wall composition analysis offers a comprehensive approach to dissecting blueberry texture. This enables breeders to select and develop blueberry varieties meeting consumer expectations, enhancing market competitiveness, and supporting the growth and sustainability of the global blueberry industry.
Speakers
JD

juan david jimenez pardo

University of Florida
Wednesday September 25, 2024 12:25pm - 12:35pm HST
Kahili

12:25pm HST

LOCSY - An expanded scope of ethnic crops research and outreach in the United States: implications on immigration and urban food
Wednesday September 25, 2024 12:25pm - 12:35pm HST
The participation of immigrant, refugee and communities of conflict-displaced former agricultural professionals in urban agriculture and local food systems has steadily increased in the United States over the past decades. Even though production and access of culturally appropriate crops has the potential to nourish the health and social fabric of communities and contribute to the local economy, less is known about the extant literature related to research and outreach on ethnic crops. This presentation will cover preliminary results of an ongoing systematic review collating peer-reviewed and gray literature published from 2000 to the present to identify, map, and describe existing research and outreach efforts on culturally relevant crops in the United States. Our findings will have the potential to offer a greater understanding of the current state of knowledge to inform the focus of future research on innovative models for more sustainable and local urban production.
Speakers
FK

Fernanda Krupek

Ohio State University
Co-authors
JK

Jacqueline Kowalski

University of Connecticut
NA
Wednesday September 25, 2024 12:25pm - 12:35pm HST
South Pacific 1

12:29pm HST

Pomology 2/Horticultural Plant Reproductive Biology (POM 2/HPRB)
Wednesday September 25, 2024 12:29pm - 1:50pm HST
Mechanization Reduces Pruning and Harvest Labor Time in the Cider Apple Orchard - Carol Miles
Testing Agronomic Strategies to Reduce Biennial Bearing in Apples - Thiago Campbell
Identifying Local Apple Germplasm for Use of Hard Ciders in North Dakota - Wenhao Dai
The Fruitlet Size Distribution Model As A Thinning Decision Aid For Precision Crop Load Management Of Apple - Laura Hillmann
Deciphering the Proline-Mediated Flowering Delay Mechanism in Peach through Physiological and Metabolic Analyses - Hyunsuk Shin
Genetic Architecture of Important Traits for Prunus Crop Improvement - Michael Itam
Taste Acidity and Other Important Fruit Characteristics of New Peach Varieties Compared with Concurrent Varieties During 2022 and 2023 - Hemant Gohil
Role of Silicon in Peach Water Stress Tolerance - Noah Willsea
Moderator
TC

Thiago Campbell

Washington State University
Wednesday September 25, 2024 12:29pm - 1:50pm HST
Coral 2

12:30pm HST

CE - Production of Red Leaf Lettuce at Vertical Farm Equipped with Blue LED According to Anthocyanin Concentration and Its Ge
Wednesday September 25, 2024 12:30pm - 12:40pm HST
At the last ASHS annual conference, I, Satitmunnaithum et al., (2023), presented our study on the effect of blue and white LED light ratio on red leaf lettuce, however, the effect of blue LED on red coloration during its growth is still unclear. Thus, at this year’s conference, we aim to clarify the mechanisms of red coloration under blue LED based on anthocyanin biosynthesis gene analysis and its content in vertical farming condition to stabilize its production for high market demand. To elucidate the effect of blue LED light on the red coloration of red leaf lettuce, green and red leaf lettuce (Lactuca sativa L.) were selected for this study. Both were hydroponically cultivated at the Advanced Plant Factory Research Center at Meiji University, Japan. The cultivation temperature was set at 22 ℃ with a humidity of 60%. Seeds were sown under white LED for 24 hours. Ten-day-old seedlings were transplanted to different light conditions: white LED and blue LED. The photoperiod was set for 16 hours. The nutrient solution was supplied at an EC of 1.6 mS/m^2 with a pH of 6.0 ± 0.5. Both light treatments had a PPFD of 100-120 µmol/m^2/s. After 20, 25, and 30 days of transplantation, lettuces were harvested. The red area on leaf lettuce, along with the total anthocyanin content and its precursors, as well as the expressions of anthocyanin biosynthesis-related genes such as ANS, CHS, bHLH, DFR, and HY5, were evaluated. Blue light shows a large red area on red leaf lettuce at most of the development stages resulting in a high red area percentage, while green leaf lettuce remained completely green in both light conditions. The interested genes were upregulated mostly in blue light irradiated red leaf lettuce which led to high total anthocyanin content. This can be assumed that blue LED light enhances anthocyanin synthesis in red leaf lettuce which can contribute to the stable production of red leaf lettuce in vertical farms.
Speakers
JS

Junjira Satitmunnaithum

Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University , Japan
Co-authors
CI

Chiharu Inoue

Daiwa House Co. Ltd.,
NA
TO

Takao Otsuka

Daiwa House Co. Ltd.,
NA
TI

Takashi Ikeda

School of Agriculture, Meiji university
NA
Wednesday September 25, 2024 12:30pm - 12:40pm HST
Coral 1

12:30pm HST

HSMP - Evaluation of anticancer activity of perennial tree seed-derived extracts on various cancer cell lines
Wednesday September 25, 2024 12:30pm - 12:40pm HST
According to the WHO, the global cancer incidence rate is increasing by more than 5% annually due to the rapid increase in the elderly population and continuous environmental degradation. The increasing rate of cancer incidence underscores the importance of developing health supplements and pharmaceutical ingredients derived from plants. Indeed, several anticancer drugs such as Taxol, vincristine, and vinblastine have been developed from plant-derived ingredients, serving as crucial resources in modern pharmaceutical development. This study evaluated the anticancer activity of extracts from seven different seeds against various cancer cell lines. Seeds from perennial trees such as Alnus japonica, Chamaecyparis obtusa, Cornus kousa, Phellodendron amurense, Pinus densiflora, Prunus sargentii, and Quercus glauca were used in the experiments. Extracts, prepared via ultrasonic extraction with 70% ethanol and concentrated to 100 µg·mL-1, were tested on lung (A549), prostate (LNCaP-LN3), melanoma (B16F10), colon (Caco-2, HCT15), and breast (MDA-MB-231) cancer cell lines using the MTT assay. In the lung cancer (A549) cell line, C. kousa, C. obtusa, and Q. glauca significantly inhibited cancer cell proliferation compared to the negative control (DMSO), with viability rates of 68.2%, 6.8%, and 44.7%, respectively. Prostate cancer (LNCaP-LN3) cells showed anticancer activity with extracts from six species, excluding P. sargentii, in the following order of cell viability: C. obtusa (8.2%) > C. kousa (15.8%) > A. japonica (35.1%) > Q. glauca (73.9%) > P. amurense (78.6%) > P. densiflora (86.3%). Cell viability was assessed for colon cancer cell lines Caco-2 and HCT15, where extracts from C. kousa (71.7% for Caco-2 and 69.9% for HCT15), C. obtusa (8.0% for Caco-2 and 7.1% for HCT15), and Q. glauca (89.9% for Caco-2) demonstrated significant inhibition of cell proliferation. For melanoma (B16F10) and breast cancer (MDA-MB-231) cell lines, extracts from C. kousa (63.8% and 66.3%, respectively) and C. obtusa (6.7% and 7.3%, respectively) showed strong anticancer activity, significantly reducing cell viability. This study suggests that the extracts from seven species of seeds can have a potent anticancer effect on specific cancer cell lines and confirms their potential as an important step in the development of anticancer ingredients derived from perennial tree seeds.
Speakers
HL

Hamin Lee

Chungbuk National University
Co-authors
JC

Ju-Sung Cho

Chungbuk Nationl University
NA
KP

Kyungtae Park

Chungbuk Nationl University
NA
YK

Youg-Rak Kwon

National Forest Seed Variety Center
NA
Wednesday September 25, 2024 12:30pm - 12:40pm HST
South Pacific 2

12:30pm HST

POM 2 - Testing Agronomic Strategies to Reduce Biennial Bearing in Apples
Wednesday September 25, 2024 12:30pm - 12:40pm HST
Biennial bearing in tree fruit can be problematic, and these patterns are not unique to tree fruit and occur in natural species. Masting, or the abundant production of seeds in some years, can also be observed in natural tree species. Despite extensive research, biennial bearing still affects commercial orchard production. Biennial bearing cycles are costly, with inconsistent yields and fruit quality occurring yearly. Crop load management is one commonly used management strategy to control biennial beating. However, trees can continue a biennial cycle the year following adequate crop thinning. We evaluated six different agronomic strategies to combat biennial bearing in apple trees; two for low-cropping trees (“off” year) and four for high-cropping trees (“on” year). In 2023, ‘Honeycrisp’ trees on B.9, G.41, G.890, and M.9-T337 rootstocks in their high-cropping year were root pruned, girdled, sprayed with ethephon, or fertilized with nitrogen (ammonium nitrate) in the fall, along with untreated control. Trees in their low-cropping year (2023) were defoliated and sprayed with gibberellic acid (GA 3 ) and untreated control. Due to the limited availability of low-cropping trees in 2023, only ‘Honeycrisp’ trees on B.9 and M.9-T337 rootstocks were used. All treatments were applied two to three weeks after full bloom except for nitrogen fertilization, which was applied in late August. Crop load, vegetative growth, and fruit quality were measured for treated trees and controls. Carryover effects of treatments were calculated to quantify the reduction/amelioration of biennial bearing incidence. In low-cropped trees, GA 3 had significantly higher return bloom from controls and defoliated trees. In high-cropped trees, no treatment had a significant effect on return bloom compared to controls. Vegetative growth was not affected by any treatment. Effective agronomic strategies for managing biennial bearing can be inconsistent and need to be further investigated for their impacts.
Speakers
TC

Thiago Campbell

Washington State University
Co-authors
LK

Lee Kalcsits

Washington State University
NA
Wednesday September 25, 2024 12:30pm - 12:40pm HST
Coral 2

12:30pm HST

VCM 2 - Insurance Industry Standards Over-estimate Yield Loss Due to Stand Reduction in Processing Sweet Corn
Wednesday September 25, 2024 12:30pm - 12:40pm HST
Sweet corn is an important processing crop in the upper Midwestern United States. It can be insured for hail losses, but actuarial tables are based on field corn. The first step in developing accurate yield loss assessments is determining yield loss due to complete plant loss. To that end, we compared ear yield of sweet corn thinned to 75, 50, or 25% of a full population at three times throughout the growing season to control plots that were not thinned. We repeated this in three consecutive years at two locations, without irrigation or supplemental fertilizer. Average yield for control plots was 16.4–20.3 Mg•ha-1. Average yield losses due to thinning were generally less than currently-used actuarial estimates. For example, average yield of sweet corn when thinned to 50% of a full population at growth stage V3–V5 was 88–96% (95%CI) of full yield. The actuarial estimate is 78% of full yield, indicating greater resilience than expected. The number of tillers per plant was greater in all thinned plots, especially those thinned early in the season. Kernel recovery was unaffected by thinning treatment in one location and declined slightly at heavy thinning in the other location. Sweet corn actuarial tables should be different from actuarial tables based on field corn.
Speakers
avatar for Charlie Rohwer

Charlie Rohwer

Scientist, University of Minnesota
Co-authors
JL

Joe Lauer

University of Wisconsin-Madison
NA
MZ

Mark Zarnstorff

National Crop Insurance Services
NA
Wednesday September 25, 2024 12:30pm - 12:40pm HST
South Pacific 3

12:30pm HST

PB 2 - Overexpression of the Coding Sequence of Ma1 Leads to Enhanced Anthocyanin Biosynthesis in Apple via MYB73.
Wednesday September 25, 2024 12:30pm - 12:45pm HST
Anthocyanins, a group of secondary metabolites synthesized in the phenylpropanoid pathway, largely determine fruit peel color of fleshy fruits, but it is not known if its synthesis is linked to vacuolar malate accumulation that determines fruit acidity. Here, we show that when the coding sequence of Ma1, the major gene controlling apple fruit acidity, is overexpressed in ‘Royal Gala’ (RG), anthocyanin biosynthesis in the fruit peel is enhanced, corresponding to the downregulation of the expression of MYB73, an R2R3-MYB transcription factor. RNAi suppression of MYB73 expression via virus-induced gene silencing increases anthocyanin biosynthesis whereas its transient overexpression decreases anthocyanin biosynthesis in apple fruit peel. MYB73 binds to the promoter of the gene encoding UDP-glycose: flavonoid-3-O-glycosyltransferase (UFGT), the enzyme that catalyzes the last step in anthocyanin synthesis, to repress its expression. When MYB73 expression is suppressed by RNAi, UFGT expression is enhanced, leading to more anthocyanin synthesis, but this effect is blocked by RNAi suppression of UFGT expression. RNAi suppression of MYB73 enhances anthocyanin synthesis in wild-type RG apples whereas its overexpression decreases anthocyanin synthesis in Ma1-OE fruit. In the meantime, MYB73 competes with MYB1, one of the key activators of anthocyanin biosynthesis, binding to the promoter of UFGT and regulating its expression. These results indicate that MYB73 negatively regulates anthocyanin biosynthesis via repressing UFGT expression in apple peel. In Ma1-OE fruit, down-regulation of MYB73 releases UFGT from MYB73 repression and allows more MYB1 binding to UFGT promoter, leading to enhanced anthocyanin biosynthesis.
Speakers
MZ

Mengxia Zhang

Cornell University
Co-authors
DH

Dagang Hu

Cornell University
NA
LC

Lailiang Cheng

Cornell University
NW

Nan Wang

Cornell University
NA
Wednesday September 25, 2024 12:30pm - 12:45pm HST
South Pacific 4

12:30pm HST

UG - Enhancing rose propagation using moisture sensor-controlled irrigation and LED supplemental lighting in greenhouses
Wednesday September 25, 2024 12:30pm - 12:45pm HST
This study addresses the critical need for precise irrigation management in the greenhouse production of high-value ornamental crops, focusing on the propagation of single-stem rose (Rosa rubiginosa) cuttings under light-emitting diode (LED) supplemental lighting. The current lack of effective monitoring and control systems for substrate moisture poses challenges in optimizing plant growth while minimizing water and nutrient losses. In this context, we propose the integration of moisture sensors for real-time monitoring and control of substrate moisture levels, coupled with LED supplemental lighting, to enhance the production of rose cuttings. Our approach involved assessing the feasibility and effectiveness of moisture sensor-controlled irrigation in greenhouses, considering the specific requirements of rose propagation and the influence of LED lighting on plant growth. We tested three Ө thresholds (0.25, 0.35, and 0.45 m3.m-3) and five light levels as supplemental lighting (100, 175, 250, 325, and 400 µmol.m-2.s-1) arranged on randomized complete block design with four replications. Rose Double Knock Out® ‘Radtko’ PP 16,202 CPBR 3,104 plants were grown in 15.6 L pots (Pioneer Pots; Blackmore Co., Belleville, MI) filled with 20% Canadian peat/58% aged pine/10% perlite/12% EZ Hydrafiber lime potting mix (Oldcastle HFC25; Oldcastle Lawn
Speakers
BT

Braylen Thomson

Undergrad Researcher, University of Georgia
Co-authors
AH

Alan Huber

University of Georgia
NA
BH

Brandon Heavern

James Greenhouses
NA
KJ

Ken James

James Greenhouses
NA
KQ

Kuan Qin

University of Georgia
LJ

Lars Jensen

Blackmore Company
NA
MH

Matthew Housley

University of Georgia
RF

Rhuanito Ferrarezi

University of Georgia
NA
Wednesday September 25, 2024 12:30pm - 12:45pm HST
Lehua Suite

12:35pm HST

FRBR - Sugar Content and Gene Expression Dynamics in Apple Spurs in Response to Fruit Load and Gibberellins
Wednesday September 25, 2024 12:35pm - 12:45pm HST
Many commercial apple (Malus x domestica Borkh.) cultivars follow a biennial bearing cycle, alternating between an “on” year with a heavy crop load and an "off" year with few if any fruit. It is commonly thought that biennial bearing is conditioned by repression of floral initiation by developing fruit. Although various studies have provided some insights into the regulation of flowering and biennial bearing by fruit load, the associated molecular-genetic pathway involved remains unclear. The objective of this study is to evaluate the influence of fruit load on the expression of specific, presumed flowering genes in the spur leaves and shoot apex, focusing on the potential role of sugars in this process. The hypothesis is that the potential accumulation of photosynthates in the leaf or shoot apex related to the absence of a strong sink (developing fruit) promotes floral initiation by directing the expression of floral-promotive genes. To test this, physiologically similar ‘Royal Red Honeycrisp’ trees were manipulated to influence fruit load. The accumulation of soluble sugars (fructose, sorbitol, glucose, and fructose) in the spur leaf and shoot apex was evaluated using a gas chromatograph. RNAs were extracted and gene expression patterns in the leaf and apex were evaluated using quantitative RT-PCR and direct sequencing; results will be presented. This study should provide new insights into the fundamental mechanisms of biennial bearing in apple. This may lead to approaches to limit the impact of biennial bearing in existing orchards, and genetic information useful for apple cultivar improvement.
Speakers
QF

Qiuyi Fu

Michigan State University
Co-authors
SV

Steve van Nocker

Michigan State University
NA
Wednesday September 25, 2024 12:35pm - 12:45pm HST
Kahili

12:35pm HST

LOCSY - Youth Sustainable Agriculture Urban Farming Entrepreneurship Program: An Overview and Pilot Results from Urban Farming
Wednesday September 25, 2024 12:35pm - 12:45pm HST
Urban agriculture initiatives developed for youth have the capacity to motivate learning, include minority groups, and allow participation in activities that foster self-growth, community engagement, and entrepreneurship. This pilot study builds on a partnership between a midwestern university and the Felege Hiywot Center’s (FHC) successful youth urban farming program, now focusing on how that programing could contribute to developing life skills, sustainable agriculture knowledge, and entrepreneurial skills. A mixed methods approach was utilized, including pre/post surveys, student presentations, and observations. Participants were twenty-eight high school aged youth, of which 91% self-identified as African American. Main foci of the project were participants’ life skills, entrepreneurial skills and mindset, sustainable agriculture content, and community collaborations. Key findings from the summer pilot post survey (n=23) indicate that 70% of participants responded that they could develop their own business plan, 83% believe that external changes create opportunities for an urban ag business; and 65% believed they could build connections with people they had not before. Knowledge around sustainable agriculture shows room for improvement where only 30% could identify what percentage of food grown globally is wasted annually, and 43% believed that technology development, adoption and utilization is not a part of sustainable agriculture; however, sixty five percent of participants could identify the three sustainability pillars: economics, environment, and social. The program's influence on participants' future plans was of interest, with 52% self-reporting a change in their outlook. This impact can be attributed to the collaborative efforts of volunteers, professionals, sponsors, and the structured nature of the FHC program, which also emphasizes the importance of individual backgrounds. The potential to impact and enhance life skills, foster self-awareness, improving family communication, and open avenues for future education and career opportunities will allow for a broader development and expansion of this project. This pilot contributes to the broader discourse on youth programs in urban agriculture by highlighting the integrative approach of experiential learning, farm-based education, and student-centered learning within a youth development framework. While early in the project, this pilot shows promise in underlining the critical role of urban agriculture programs in shaping the lives and future prospects of minority youth.
Speakers
KO

Kathryn Orvis

Professor, Purdue Univ
Co-authors
AB

Aster Bekele

Felege Hiywot Center
NA
DI

Delphine Iradukunda

Purdue Univ
NA
NS

Nathan Shoaf

Purdue University
NA
TN

THEONESTE NZARAMYIMANA

Kentucky State University
Wednesday September 25, 2024 12:35pm - 12:45pm HST
South Pacific 1

12:35pm HST

Exhibitor Talk: Conviron
Wednesday September 25, 2024 12:35pm - 12:50pm HST
This year Conviron is launching three new products:
•             GEN1000-ECO (introduction date: April 16, 2024)
•             ConvironDirect (introduction date: March 4, 2024)
•             PGR15/E15 LED Retrofit (introduction date: Jan 5, 2024)
GEN-1000-ECO:
The GEN1000-ECO is a new compact reach in chamber ideal for short and tall plant research that comes standard with humidity control and energy efficient features such as a smaller compressor and LED lighting - for up to 15% reduced energy consumption. Low, medium and high light options are available to meet a range of research requirements.
ConvironDirect:
ConvironDirect is a new premium software tool that enables users to manage chamber setpoints and actual conditions remotely through any building LAN connected desktop, notebook or handheld mobile device. ConvironDirect is ideal for users that have Conviron reach-in plant growth chambers or walk-in rooms and want a seamless connection to their chamber, their plants, and their data from virtually anywhere.
PGR15/E15 LED Retrofit:
Fluorescent lamps such as T5, T8 and T12 have been the standard for many years and have been used in tens of thousands of plant growth chambers around the world. However, fluorescent lighting is trending towards obsolescence and replacement lights are increasingly difficult to source economically. Conviron is now offering a retrofit for aged PGR15-E15 chambers to enable users to take advantage of the latest LED lighting technology and save up to 80% on energy costs.
Wednesday September 25, 2024 12:35pm - 12:50pm HST
Coral 5

12:40pm HST

CE - Interlighting Improves Tomato Yield in Northern Greenhouses
Wednesday September 25, 2024 12:40pm - 12:50pm HST
Low natural light and high heating costs limit northern winter greenhouse production. Technology advancements now offer opportunities to improve delivery of light to and within crop canopies. The greenhouse tomato cultivars Bigdena and Beorange were chosen to evaluate high pressure sodium irradiance with LED interlighting. Plants were grown in a high-wire drip irrigation system using dutch (bato) buckets (17.7 L volume) filled with a 50/50 mixture of perlite and a peatlite medium (Pro-Mix BX). The containers were placed in alternating rows across a drainpipe. Seeds were sown on 8 Sep and two seedlings were transplanted into each container 38 d later (17 Oct). Day temperature was 22 ± 2°C and reduced to 18 ± 2°C during the night. Lower leaves were removed as fruit ripened and the study was terminated at a plant height of ~250 cm (128 d from transplanting). The photoperiod was 18-h. In addition to overhead 400-W HPS lighting, LED fixtures designed for placement within the canopy were evaluated (GE current Arize® Integral). Two horizontal LED bars were positioned 30 cm (12 inches) apart with the upper bar adjusted within 30 cm of the top of the plants throughout the study. The integral lighting provided a spectrum with blue (peak 450 nm) and red (peak 660 nm) wavelengths in a 12:88 ratio. The perpendicular horizontal distance from the LED bars to the plant stems was 30 to 35 cm. The intensity (400-700 nm) measured at the plant stems horizontally from the LEDs averaged 195 ± 30 µmol m-2s-1. Overhead HPS provided ~130 ± 20 µmol m-2s-1, 100 cm below the fixtures. Seasonally short days and low sun angles limited natural light during the study. The first ripe tomatoes were harvested 62 d from transplanting (18 Dec). Interlighting resulted in higher plant yields with 6.3 ± 0.82 kg for Bigdena and 4.9 ± 0.67 kg for Beorange. In comparison, 4.1 ± 0.37 kg (Bigdena) or 3.4 ± 0.80 kg (Beorange) was recorded for plants receiving only HPS lighting. Five or six additional tomatoes were harvested with interlighting for Bigdena (25 ± 2.0 versus 19 ± 1.8) and Beorange (22 ± 2.5 versus 17 ± 1.9). Average tomato size increased from 217 ± 11.9 g to 250 ± 19.3 g (Bigdena) or from 199 ± 36.1 g to 227 ± 20.2 g (Beorange) with interlighting.
Speakers
MK

Meriam Karlsson

University of Alaska Fairbanks
Co-authors
EC

Eric Cook

University of Alaska Fairbanks
NA
Wednesday September 25, 2024 12:40pm - 12:50pm HST
Coral 1

12:40pm HST

HSMP - Exploring the Potential of Annonacin and 2-Deoxy-D-glucose on Non-Small Cell Lung Cancer Cells
Wednesday September 25, 2024 12:40pm - 12:50pm HST
Annonacin is a natural compound found in the fruit of a number of members of the Annonaceae family, including soursop and Asimina triloba. This compound has promise in targeting vital metabolic pathways, inhibiting mitochondrial complex I, and exploiting the altered energy dynamics of cancer cells that lead to apoptosis. Non-small cell Lung Cancer (NSCLC) accounts for approximately 80% of all lung cancer cases and remains a leading cause of cancer-related mortality worldwide. Despite advancements in cancer treatment, the five-year survival rate of NSCLC is low, justifying the urgent need for innovative and effective therapeutic approaches. The aberrant energy metabolism, which is a hallmark of cancer, including NSCLC, known as the Warburg effect, makes it a potential target for therapeutic interventions. In addition, 2-Deoxy-D-glucose (2DG) is a glucose analog widely studied for its ability to target the glycolytic pathway of energy metabolism of cancer. The potential combination of Annonacin and 2DG acting synergistically to inhibit the growth of A549 NSCLC cells could lead to new treatment options. The objective of this study was to examine glycolytic and mitochondrial complex I inhibitors individually and in combination to target energy metabolism to inhibit A549 NSCLC cell growth as novel antitumor agents. The study was carried out in an in vitro model system using the A549 NSCLC cell line, where the NL20 Bronchial Epithelium cell line was used as a parallel control. Cells were treated with 0 µM, 2 µM, 4 µM, and 6 µM concentrations of Annonacin and 0 mM, 2.5 mM, 5 mM, and 10 mM concentrations of 2DG, both individually and in combination in triplicate experimental design with control. The MTT assay was employed to determine immediate cell viability and assess the applied treatment's cytotoxic effects. The oxidative stress in treated and control cells was determined through superoxide dismutase and glutathione peroxidase assays. Furthermore, the long-term proliferative capacity of the cells post-treatment was examined using a colony-forming assay. The implications of the combined application of 2DG and Annonacin on A549 NSCLC cell viability and potential as a treatment of NSCLC will be discussed. These findings need further investigation to elucidate the underlying mechanisms and explore the in vivo and clinical applicability details for the combined administration of Annonacin and 2DG's use in NSCLC treatment.
Speakers
BR

Bhoj Raj Bhattarai

Kentucky State University
Co-authors
AT

Avinash Tope

Kentucky State University
NA
CT

Cora Teets

Kentucky State University
NA
KP

Kirk Pomper

Kentucky State University
Dr. Kirk W. Pomper is the Professor of Horticulture in the College of Agriculture, Community, and the Sciences at Kentucky State University in Frankfort, Kentucky. As Horticulture Research Leader, his program is focused on research and Extension efforts toward developing pawpaw as... Read More →
Wednesday September 25, 2024 12:40pm - 12:50pm HST
South Pacific 2

12:40pm HST

POM 2 - Identifying Local Apple Germplasm for Use of Hard Ciders in North Dakota
Wednesday September 25, 2024 12:40pm - 12:50pm HST
Hard cider is one of the fastest growing specialty beverages in the United States with an average annual retail sales of about $500 million in recent years. Cider apples refer to those that are specifically used for hard ciders (alcoholic) with unique traits, such as high acid, high tannin, and high total soluble solid that help ferment superior-quality hard ciders. In traditional hard cider production countries, hard ciders are made from cider-specific cultivars; however, hard ciders in the US are usually made from apples that were bred for fresh apple market because of inadequate fruit availability of cider-specific cultivars. In this study, apple germplasm grown at the NDSU Horticulture Research Farm near Amenia, ND (USDA hardiness zone 3-4a) was evaluated for the suitability of quality hard ciders. Specifically, four biochemical traits, total soluble solids (TSS), pH, titratable acidity (TA), and total phenolic compounds (TPC) that are the general attributes to the quality of hard ciders, were analyzed. Preliminary results showed that the average TSS was 15.75o Brix with the highest TSS reached 21.2o Brix. The fruit of some lines were very sour and tart indicating the high level of acidity and phenolics, which showed the great potential for quality hard cider production. The titratable acidity (malic acid) and total phenolic compounds in the apple juice of selected lines are being quantified. This research could identify local cider apple germplasm and provide apple growers and cider makers with the information on cultivar selections for quality hard cider production in ND and the surrounding region.
Speakers
WD

Wenhao Dai

North Dakota State University
Co-authors
BT

Brent Trela

Trelab
NA
MM

Mika Mzumara

North Dakota State University
NA
TS

Tian Sun

North Dakota State University
NA
ZJ

Zhao Jin

North Dakota State University
NA
Wednesday September 25, 2024 12:40pm - 12:50pm HST
Coral 2

12:40pm HST

VCM 2 - Combining Lasers and Distress Calls to Control Birds in Sweet Corn
Wednesday September 25, 2024 12:40pm - 12:50pm HST
Red-winged blackbirds (Agelaius phoeniceus) and European starlings (Sturnus vulgaris) cause significant damage to sweet corn (Zea mays). Even minor damage can render ears unmarketable and the need to sort out damaged ears during packing increases costs for growers. Propane cannons and pyrotechnics have long been the preferred methods for preventing birds from damaging corn, but both methods create noise pollution and conflicts with farm neighbors. Automated laser scarecrows and automated recordings of bird distress and predator calls are two newer technologies for deterring birds from crops. We tested both technologies on a research farm in Kingston, Rhode Island and in commercial processing sweet corn fields in western New York in 2022 and 2023. All experiments used naturally occurring flocks of wild birds; flock size and species makeup varied between fields and over time. The automated laser scarecrows (LS) were designed and built by the URI Laser Scarecrow Project; they utilized a 50 mW 532 nm green laser with a beam diameter of 14 mm at the aperture and a dispersion of 4 mrad. Vertical and horizontal movement of the beam was randomized by a microcontroller. Bird Gard Super Pro units (BG) randomly played digital recordings of distress and alarm calls of red-winged blackbirds and European starlings and hunting calls of hawks and falcons. Data were collected as counts of damaged ears and converted to percentage of total ears for analysis. In Rhode Island the effect of laser scarecrow alone was compared to the effect of the laser scarecrow combined with the bird distress calls. In New York the two deterrent treatments were also compared to an unprotected control. In Rhode Island in 2022 bird damage averaged 20.7% with just LS and 7.1% with LS BG; the difference was significant at P
Speakers Co-authors
JK

Julie Kikkert

Cornell Cooperative Extension
NA
Wednesday September 25, 2024 12:40pm - 12:50pm HST
South Pacific 3

12:44pm HST

Floriculture (FLOR)
Wednesday September 25, 2024 12:44pm - 2:05pm HST
Peperomia mauiensis can tolerate low indoor light conditions for up to 12 months - Orville Baldos
Effect of LED Lighting, Fertilization Rates and Gibberellin A3 Application to Greenhouse Grown Geranium (Pelargonium x hortorum) 'Red Maverick' Plants - Sonja Maki
Investigating the Effect of Hydrafiber and Biochar As a Substitute for Peat-based Substrate for Zinnia (Zinnia elegans) - Lilin Chen
The Impact of Cold and Darkness on Osmanthus fragrans Flowering and Growth - Yulong Chen
Growth and Quality of Four Zinnia Cultivars Grown in Eastern South Dakota - Kristine Lang
Effects of Photoperiod Treatments on Stock Plants and Cutting Rooting of Callirhoe involucrata - James Klett
Consumer testing and surveys indicate a market for Peperomia mauiensis, an endemic succulent with potential use as an indoor potted plant - Orville Baldos
Trials of Low Elevation Tolerant Leucospermum Hybrids on Oahu, HI - Russell Galanti
Moderator
SM

Sonja Maki

University of Wisconsin-River Falls
Wednesday September 25, 2024 12:44pm - 2:05pm HST
Nautilus 1

12:45pm HST

FLOR - Peperomia mauiensis can tolerate low indoor light conditions for up to 12 months
Wednesday September 25, 2024 12:45pm - 12:55pm HST
Peperomia mauiensis is an endemic peperomia found on west Maui, and the islands of Molokai and Lanai. Its short stature and reddish stems and leaves make it highly ornamental. To evaluate its feasibility as an indoor foliage plant, potted plants (n=6) were grown under three light levels (0.2 mol·m-2·d-1 [low], 0.4 mol·m-2·d-1 [office] and 2.9 mol·m-2·d-1 [high] for 12 hours) in airconditioned settings (22°C, 61% RH) for 1 year. Plant height and diameter as well as visual quality [1 = poor, 2 = fair (not saleable), 3 = acceptable (saleable), 4 = good, and 5 = excellent quality) were recorded 0, 3, 6 and 12 months after placing in light chambers. Height and diameter of plants between light treatments were similar at 0 (height = 5.9 cm; diameter = 10.5 cm) and 3 (height = 7.1 cm and diameter = 15.0 cm) months after the plants were placed in light chambers. Visual quality ratings also did not differ between light treatments at 0 (3.5) and after 3 (3.6) months. After 6 months, plants under office light conditions were the tallest (10.8 cm) and the widest (18.2 cm). Visual quality ratings between treatments at 6 months were similar (3.4). At 12 months, plant height between treatments were similar (8.8 cm), but office light plants exhibited the widest diameter (23.2 cm). Visual quality ratings between treatments at 12 months were similar (2.1) but was no longer acceptable. Results of the study indicate that Peperomia mauiensis can tolerate low indoor light levels and can be used as an indoor potted foliage plant.
Speakers
OB

Orville Baldos

University of Hawaii at Manoa
Co-authors
CW

Christyn Wong

Hawaii Department of Agriculture
NA
LW

Lindsey Watanabe

University of Hawaii at Manoa
NA
SA

Sherry Ann Hara

University of Hawaii at Manoa
NA
Wednesday September 25, 2024 12:45pm - 12:55pm HST
Nautilus 1

12:45pm HST

FRBR - A Census and The Conservation of Malus coronaria in Michigan
Wednesday September 25, 2024 12:45pm - 12:55pm HST
Crop wild relatives are important genetic resources for cultivar improvement. Domesticated apple (M. x domestica) cultivars grown in North America are heterogeneous hybrids of Asian and European Malus species, with no known genetic contribution from native apples. M. coronaria (Sweet Crabapple) is the only native apple species found within the major apple-producing Great Lakes region. In spite of its potential importance for apple cultivar improvement, the genetics of this species has not been well studied, and only a few accessions are maintained in the USDA National Plant Germplasm System (NPGS). The objective of this research was to identify and collect new accessions of M. coronaria for the NPGS, focusing on the northernmost extent of its range in Michigan. To locate living trees, we combined analyses of historical records in 12 herbaria and the North America Fruit and Nut Tree Data, along with crowdsourcing using the popular online platform, iNaturalist. We identified a total of 158 M. coronaria records from herbaria and the fruit tree dataset. Records were removed from consideration if they were cataloged earlier than 1950, did not include collection coordinates, were redundant, or were not collected in the state of Michigan. iNaturalist listed 309 sightings of M. coronaria in Michigan; of these, we determined that a majority were likely misidentified based on the phenotypic characteristics in the images provided by the observer. Finally, Google Earth was used to rule out locations where the M. coronaria individuals had likely been lost due to anthropogenic activity. Ultimately, this three-factored approach identified only 64 sites within the state of Michigan where a living tree would likely be found. Our results provide strong evidence that M. coronaria is in decline within its native range in Michigan, underscoring the importance of conservation efforts for this species.
Speakers
LC

Lily Christian

Michigan State University
Co-authors
SV

Steve Vannocker

Michigan State University
NA
Wednesday September 25, 2024 12:45pm - 12:55pm HST
Kahili

12:45pm HST

LOCSY - Connecting the Dots: Creating School Garden and Produce Taste Testing Programs in Kentucky
Wednesday September 25, 2024 12:45pm - 12:55pm HST
More than one-third of adolescents are overweight or obese in Kentucky. Access to and consumption of fruits and vegetables is important to maintain a healthy weight and reduce disease risk; however, in Kentucky adolescents, 44.6% reported consuming fruit less than once daily and 42.7% reported consuming vegetables less than once daily. Research has shown that farm to school (F2S) activities lead to improvements in student health behaviors, including: an increase in the consumption of and preference for fruits and vegetables, and improved knowledge and attitudes to nutrition. F2S activities have been shown to have strong benefits relative to economic development, public health, education, environment, and equity and community engagement and include 3 core elements – procurement of local food by schools, agriculture, food, health, and nutrition education, and school gardens. The University of Kentucky (UK), the Kentucky Horticulture Council (KHC), Feeding KY, Community Farm Alliance (CFA), and the Kentucky Department of Agriculture (KDA) partnered to develop a Kentucky F2S Network and awarded 40 schools mini-grants to implement taste testing activities and awarded 5 schools mini-grants to establish school gardens and implement nutrition and food education in the classroom. More than 35 applications for the school garden mini-grants were submitted and 5 schools received $5,000 to install school gardens and conduct related nutrition and cooking education. UK student interns assisted schools and conducted garden/nutrition lessons, reaching over 2,000 students. Garden grantees grew and harvested 35 fruits and vegetables. During the final project reporting period, grantees engaged over 2,000 people in gardens for a total of 3,000 hours collectively spent in the garden with 1,300 of those hours coming from parent and community member involvement. Interns presented 3 school garden educator workshops and developed resources about best practices for school gardens. Over 100 applications were received for $1,000 taste test mini-grants and 40 grants were awarded directly to KY schools to conduct taste test activities of locally-grown fruits and vegetables. The taste testing grantees: purchased $24,369 in produce from 90 Kentucky farms; served 70 different types of fruits and vegetables; and served locally-grown produce to 11,000 students in 55 different schools. The presentation will focus on strategies used to recruit and screen program participants by assessing needs, setting realistic expectations, and increasing production knowledge and skills, with the goal of influencing student food choices and increasing use of locally-grown produce in classroom education and school feeding programs.
Speakers
CF

Cindy Finneseth

Kentucky Horticulture Council
Co-authors
KO

Kendra OoNorasak

University of Kentucky
NA
MF

McKenzie Fox-Potter

Kentucky Horticulture Council
NA
Wednesday September 25, 2024 12:45pm - 12:55pm HST
South Pacific 1

12:45pm HST

PB 2 - Rapid Detection and Coinfection Analysis of Aspergillus flavus in Peanut Seeds
Wednesday September 25, 2024 12:45pm - 1:00pm HST
Aspergillus flavus is a widespread pathogen affecting crops like peanuts, contributing significantly to mycotoxin contamination and subsequent crop losses. Discriminating between toxigenic and non-toxigenic strains is crucial, yet conventional methods are often cumbersome and time-consuming. In this study, we developed rapid molecular tools to differentiate between these strains. Using morphological characteristics and species-specific PCR-sequencing, we identified isolates collected from peanut seeds in southern Georgia. Through primer optimization and qPCR targeting aflatoxin regulatory genes, we successfully distinguished aflatoxin-producing and non-producing isolates. Additional genes involved in aflatoxin biosynthesis were also analyzed, showing clear expression distinctions. Our findings demonstrate the specificity and efficiency of these primer sets, providing a valuable tool for managing A. flavus contamination in peanut seed lots. Additionally, research on the seed microbiome's impact on mycotoxin production remains limited. In this study, we assessed microbial communities in peanut seeds collected over various years using ITS gene sequencing. Our results revealed a diverse microbial population, including A. flavus and other fungal pathogens, highlighting the complexity of seed microbiota. This approach offers novel insights into peanut seed-associated microbiomes and aflatoxin contamination, shedding light on the correlation between microbial communities and aflatoxin pollution.
Speakers
EA

Emran Ali

Alcorn State University
Co-authors
SW

Sumyya Waliullah

Alcorn State University
NA
VN

Victor Njiti

Alcorn State University
NA
Wednesday September 25, 2024 12:45pm - 1:00pm HST
South Pacific 4

12:45pm HST

UG - A Comparative Study Analyzing Light Lengths for the Growth of Rex Butterhead Lettuce Utilizing GREENBOX Technology
Wednesday September 25, 2024 12:45pm - 1:00pm HST
Exponential population growth adds increasing pressure on the agriculture industry to grow and distribute fresh foods to rural and urban areas, leading to the development of GREENBOX technology, which utilizes Controlled Environment Agriculture (CEA) principles to optimize the desired conditions for growth of leafy green crops. Using commercially available equipment, GREENBOX technology has the capability to be integrated into existing urban infrastructure to help relieve the negative impact urbanization has on the availability of fresh foods. GREENBOX technology allows environmental variables, such as temperature, humidity, light intensity/ spectrum, and nutrient delivery, to be controlled to enhance the growth performance of leafy greens. Precursory experiments using GREENBOX Technology utilized the standard photoperiod of 16 hours of light, and 8 hours of dark for all crop production. The main objective of this study was to conduct a comparative analysis of Lactuca sativa Rex Butterhead Lettuce production grown under different photoperiods using GREENBOX technology. Using the standard 16 hours of light and 8 hours of dark as the control, two different photoperiod treatments were tested. Treatment one consisted of a 14-hour light period and a 10-hour dark period, while treatment two consisted of a 12-hour light period and a 12-hour dark period. The biomass and productivity of the crops were measured in addition to the environmental conditions for each lighting regimen to ascertain any significant differences. The biomass parameters included wet weight (g), dry weight (g), leaf area (cm2), leaf count (n), and chlorophyll concentration (mg/cm2). We derived additional data, including the Leaf Area Index (LAI, cm2/cm2), Specific Leaf Area (SLA, cm2/g), and biomass productivity (kg/m2). A statistical analysis of the biomass data was used to understand the differences in biomass parameters between crop growth and different light lengths. No statistically significant differences were found between the biomass and productivity parameters for the 12-hour and 14-hour photoperiods. However, the weight weights, dry weights, Leaf Count, SLA, and LAI from the 16-hour photoperiod showed statistically significant differences from the 12 and 14-hour photoperiods. All treatments still produced Rex Butterhead lettuce above the expected harvest weight of 180g and are viable for crop production in urban warehouse settings. The results of this experiment may help us understand the relationship between photoperiod and the biomass performance of leafy greens. Future GREENBOX experiments may use this information to increase the efficiency and productivity outputs of GREENBOX units. Keywords: CEA, Hydroponics, lettuce, soilless agriculture, urban agriculture
Speakers
MG

Mya Griffith

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
BR

Barry Rosen

Florida Gulf Coast University
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
GB

George Buss

Florida Gulf Coast University
JG

John Griffis

Florida Gulf Coast University
NA
KJ

Kathryn Jackson

Independent Researcher
NA
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 12:45pm - 1:00pm HST
Lehua Suite

12:50pm HST

CE - Assessing the Impact of UV-C Treatment on Growth Parameters and Nutrient Levels in Hydroponic Systems for Romaine Lettuc
Wednesday September 25, 2024 12:50pm - 1:00pm HST
Introduction: Preliminary studies have shown that ultraviolet treatment is able to reduce microbial contamination in the nutrient water of hydroponic systems. However, it is not known how these ultraviolet treatments may impact nutrient water chemistry or crop growth and yield. Purpose: The objective of this study is to examine the impact of an ultraviolet light treatment on romaine lettuce growth parameters and nutrient levels in the treated hydroponic water. Methods: Commercially-available DWC (Deep Water Culture) hydroponic systems were used to grow romaine lettuce (Latticua lettuceia var. Sparx) in a two-part nutrient solution (Hydro-Gro Leafy and calcium nitrate). The electrical conductivity (EC) was maintained between 1.6 and 1.8 mS/cm during the study. The nutrient solution was treated with a UV-C device (MiniPure MIN-1; 500ml capacity) emitting peak irradiance at 254nm at flow rates of 0, 3 and 6 L/min. Water samples were collected before and after each treatment and the experiment will be repeated twice for a total of three times. Twice weekly during the six-week growth period, parameters including plant height, SPAD value, and chlorophyll fluorescence were measured. At the end of the production, fresh weight and dry weight of each plant sample were measured. Results: Low and high UV doses resulted in 1.17 and 1.36 log reductions of Escherichia coli in hydroponic nutrient water. Preliminary findings for the effect of UV light on the concentration of nutrients (NPK) yielded no significant difference in the nutrient level. The study is underway for assessing the effect on the lettuce growth parameters and therefore we are not reporting any results on the crop growth parameters. Significance: UV light technology at optimized dosage levels has the potential to improve the safety of hydroponic systems with minimal effect on the plant growth and nutrient water.
Speakers
MM

Markanna Moore

Kansas State University
Co-authors
EP

Eleni Pliakoni

Kansas State University
MJ

Majid JaberiDouraki

Kansas State University
NA
MB

Manreet Bhullar

Kansas State University
TY

Teng Yang

Kansas State University
Wednesday September 25, 2024 12:50pm - 1:00pm HST
Coral 1

12:50pm HST

HSMP - Responses and relationship between bioactive compounds and phenotypic traits in Dahurian angelica breeding lines
Wednesday September 25, 2024 12:50pm - 1:00pm HST
Dahurian angelica (Angelica dahurica (Fisch. ex Hoffm.) Benth.
Speakers
EJ

Eun Jeong Koh

Gyeongsangbuk-do Agricultural Research
NA
Co-authors
BS

Beong Sung Kim

Gyeongsangbuk-do Agricultural Research
NA
JK

Jiwon Kim

Gyeongsangbuk-do Agricultural Research
NA
JH

Joong Hwan Lee

Gyeongsangbuk-do Agricultural Research
NA
Wednesday September 25, 2024 12:50pm - 1:00pm HST
South Pacific 2

12:50pm HST

POM 2 - The Fruitlet Size Distribution Model As A Thinning Decision Aid For Precision Crop Load Management Of Apple
Wednesday September 25, 2024 12:50pm - 1:00pm HST
Fruit quality of apple is heavily influenced by crop load management practices. During the developmental window between bloom and 15mm fruitlet diameter, the general commercial practice is to apply chemical thinners to reduce the initial crop load based on the cultivar and market. However, thinning success varies from year to year, depending on bloom density, thinner selection and dose, climatic factors, tree health and cultivar. Precision crop load models such as the pollen tube growth model, the MaluSim model, and the fruit growth rate model have improved thinning success; however, labor-intensive measures has hindered broad adoption of the latter model which effectively predicts fruit set following thinner application. To improve grower adoption, we developed an alternative, time-efficient fruit set prediction model. The model has been tested on multiple cultivars over a three-year period at four distinct apple production regions throughout the United States. Abscission probabilities and fruit set predictions are based on the distribution of fruitlet mass and confirmed by actual measures of fruit set. The model starts at 6 mm fruitlet diameter and accounts for all thinners up to this time. A prediction is returned in ~8 days to inform repeat thinner applications while fruitlets are still highly sensitive to thinners. A user-guide, digital balance that automatically exports fruit mass to a laptop/tablet, and a macro-enabled Excel spreadsheet file have been developed and are available to growers to increase the precision around crop load management.
Speakers
LH

Laura Hillmann

Michigan State University
Co-authors
SS

Sara Serra

Washington State University
NA
SM

Stefano Musacchi

Washington State University
NA
TR

Terence Robinson

Cornell University
NA
TE

Todd Einhorn

Michigan State University
NA
TK

Tom Kon

North Carolina State University
NA
Wednesday September 25, 2024 12:50pm - 1:00pm HST
Coral 2

12:50pm HST

VCM 2 - Pea-oat Green Manure and Reduced Nitrogen Rate Delay Maturity of Broccoli But Do Not Reduce Yield
Wednesday September 25, 2024 12:50pm - 1:00pm HST
Cover crop biomass can provide nitrogen (N) to a sequential cash crop as a ‘green manure’, whether the N is sourced from the atmosphere or from the soil. For short-season vegetable crops in Minnesota, like transplanted broccoli, there is time for a cover crop to be grown before or after the main crop. Growing a pea-oat cover crop early in the spring, before broccoli, may increase the N available to the broccoli. However, immobilization of green manure N may reduce N availability at a time of high N demand in broccoli. In order to study N availability to broccoli provided by a spring-planted pea-oat cover crop mix, four reduced-rate nitrogen treatments were applied to two broccoli hybrids (‘Green Magic’ or ‘Gypsy’) after a spring-planted pea-oat cover crop was incorporated. Yield and maturity of broccoli were compared to broccoli grown without green manure and given a full nitrogen rate (170 kg N / ha). The fertilizer treatments included slow-release urea (139 or 110 kg N / ha), composted poultry litter with blood meal at ~110 kg N available / ha, and turkey manure applied with blood meal in the autumn before growing green manure and broccoli (~110 kg N available / ha). There was no reduction in total yield (7900 kg / ha) or marketability (>95%), but maturity was delayed by ~2 days for most treatments. A microbial inoculant (Nature’s Source®) applied to the soil at planting did not have a measurable impact on any response.
Speakers
avatar for Charlie Rohwer

Charlie Rohwer

Scientist, University of Minnesota
Wednesday September 25, 2024 12:50pm - 1:00pm HST
South Pacific 3

12:55pm HST

FLOR - Effect of LED Lighting, Fertilization Rates and Gibberellin A3 Application to Greenhouse Grown Geranium (Pelargonium x hortorum) 'Red Maverick' Plants
Wednesday September 25, 2024 12:55pm - 1:05pm HST
The effect of LED lighting, fertilization rate and gibberellin application on geranium (Pelargonium x hortorum) 'Red Maverick' plants in a greenhouse setting was evaluated. Seeds were germinated in 288 plug trays, transplanted to 3-1/2 inch geranium pots in a peat-based media (ProMix) and grown in a greenhouse environment. Twelve treatments consisting of plants that received either no, 150 ppm or 300 ppm 20-20-20 weekly fertilizer applications following transplant, abmbient or LED (Phillips Red/Blue) greenhouse lighting, and a treatment of either no or 10 ppm gibberellin A3 (GA3; ProGibb) were evaluated by recording weekly height measurements, pH, electrical conductivity (EC), and floral bud appearance was recorded for each treatment. The tallest, most advanced plants were obtained from ambient light, high fertility and ProGibb application with the shortest plants were produced by the ambient light, no fertilization, and no gibberellin application treatment. Visible bud was first noticed in the LED light grown plants at low and high fertility with and without gibberellin application. The results of this study will aid greenhouse growers producing geranium crops under different greenhouse lighting conditions to consider fertility rates and gibberellin application to decrease the production time of geranium crops.
Speakers
SM

Sonja Maki

University of Wisconsin-River Falls
Co-authors
ZE

Zachary Endreas

University of Wisconsin-River Falls
NA
Wednesday September 25, 2024 12:55pm - 1:05pm HST
Nautilus 1

12:55pm HST

LOCSY - Garden to Pantry: An Interactive and Interdisciplinary Approach to Growing and Preserving Produce
Wednesday September 25, 2024 12:55pm - 1:05pm HST
Garden to Pantry: An Interactive and Interdisciplinary Approach to Growing and Preserving Produce Rebecca C. Lee1 and Carmen Flammini2, 1 Alabama Cooperative Extension Service, Jon Archer Agricultural Center, 1070 N. Schillinger Rd., Mobile, AL 36608, 2Alabama Cooperative Extension Service, 302A Byrne St., Bay Minette, AL 36507 Recent research conducted post-COVID-19 indicates that households experiencing food insecurity have escalated their home food procurement activities, including gardening, fishing, canning, and food preservation. These studies propose that transitioning procurement activities into sustainable lifestyles and enhancing fruit and vegetable consumption among food-insecure populations will necessitate technical support and outreach initiatives like Garden to Pantry (G2P). Home gardening and food preservation programs can play a vital role in educating communities about fruit and vegetable cultivation and preservation. The objectives of the Alabama Cooperative Extension Service (ACES) program entitled ‘Garden to Pantry: An Interactive and Interdisciplinary Approach to Growing and Preserving Produce’ aimed to deliver a complete and immersive program from planting to preserving of seasonal fruit and vegetables in a one-day program by offering research-based recommendations for methods of home food preservation. Additionally, the program aimed to provide the community with cross-discipline knowledge and experience from varying disciplines. The pilot program of the ‘Garden to Pantry: An Interactive and Interdisciplinary Approach to Growing and Preserving Produce’ program was presented in five counties in Alabama in 2023 and 2024. Data obtained during the 2023 run of the program revealed the program was positively received by the target community and further interest was expressed in participating in other programs focusing on food safety as a whole concept by integrating all aspects of food preservation. Future challenges of this program include seeking involvement with younger stakeholder demographics as well as individuals interested in the increasing popular homesteading movement.
Speakers
avatar for Rebecca Catalena

Rebecca Catalena

Food Safety & Quality, Alabama Extension
Rebecca Catalena is a Regional Extension Agent in Food Safety & Quality. Rebecca received her Master’s in Public Health (MPH) from the University of West Florida and an A.A.S degree from Le Cordon Bleu. Before joining the Alabama Extension family, Rebecca served seven years in... Read More →
Co-authors
CF

Carment Flammini

Alabama Extension
NA
DR

Dani Reams

Alabama Extension
NA
Wednesday September 25, 2024 12:55pm - 1:05pm HST
South Pacific 1

12:55pm HST

Exhibitor Talk: Moss Robotics
Wednesday September 25, 2024 12:55pm - 1:10pm HST
Wednesday September 25, 2024 12:55pm - 1:10pm HST
Coral 5

1:00pm HST

CE - Effect of low root-zone temperature and UV radiation on growth and gene expression of secondary metabolite pathways in N
Wednesday September 25, 2024 1:00pm - 1:10pm HST
This study explored the effects of low root-zone temperature (LT) and UV radiation (UV) alone and combined on changes in growth, transcription, and gene expression related to secondary metabolite in Nicotidana benthamiana. The plants were grown in a controlled environment (25/20°C, 16/8 h [light/dark], 70% relative humidity, 1,000 µmol·mol−1 CO2 with photosynthetic photon flux densities of 100 and 200 µmol·m−2·s−1 for 10 and 18 d, respectively). Twenty-eight days after sowing, the seedlings were treated with LT (15°C), 0.3 W·m−2 of UV radiation, and a combined treatment with LT and UV (LT*UV) for 3 d. Results found that the treatment with UV alone decreased the quantum efficiency of photosystem II by approximately 1.5 times, and most growth characteristics decreased under the UV (approximately 1.5 times) and LT*UV treatments. Combined treatment with LT*UV significantly inhibited the growth characteristics and photosynthetic rates compared to those under the single LT and UV treatments. In particular, the transcriptome levels of phenylpropanoid and flavonoid biosynthesis were the most significantly affected by LT*UV. This suggests the potential of using LT treatment in hydroponic systems and UV radiation to control the synthesis of health-promoting compounds of secondary metabolites in greenhouses and controlled-environment agricultural facilities.
Speakers
KS

KiHo Son

Gyeonsang National University
Co-authors
EG

Eiji Goto

China university
NA
Wednesday September 25, 2024 1:00pm - 1:10pm HST
Coral 1

1:00pm HST

HSMP - Effects of Foliar Application of Humic Acid and NPK Fertilizers to the Soil on Important Growth Indices of Black Mustard
Wednesday September 25, 2024 1:00pm - 1:10pm HST
Humic acid that improves plant growth and yield indices such as fresh and dry weights, plant height. Field experiment was conducted at the Al-Mussaib Technical Institute/Iraq during the 2022-2023 season to study the effect of adding NPK complex fertilizer to the soil and spraying with organic fertilizer (Humic acid) on the growth and yield of black mustard plants, according to a randomized complete block design (RCBD) with three replications. In this study, the effect of foliar application of Humic acid and/or fertilizers of NPK on the growth characteristics of black mustard (Brassica nigar) in field conditions were compared. According to the results, the foliar application of Humic acid The results were analyzed according to analysis of variance, and the means were compared using the least significant difference (LSD) test under the probability level of 0.05.A two-factor experiment (3×3) was carried out. The first factor was the addition of a balanced NPK complex fertilizer (20:20:20). At levels of (0, 30, or 60) kg/dunum in two batches, the first two weeks after germination, and the second when flowering begins. The fertilizer was placed about 10 cm under the plant in the furrows and covered with dirt, then watered after fertilization. The second factor was spraying with three concentrations of organic fertilizer (Humic acid) (0, 2, or 4) ml.l-1. It was observed from the results that adding NPK complex fertilizer and organic fertilizer (Humic acid) has a significant effect on the characteristics of vegetative growth, as is evident from the fact that the levels of NPK complex fertilizer and spraying with organic fertilizer (Humic acid) have a significant effect on the productive characteristics of the plant. It is conclude from this experiment that the most effective treatment that can be used to feed the black mustard plant under the conditions of this experiment, and which achieved the best results in improving the vegetative and productive characteristics of the plant, is the 60 kg overlap treatment. 1 dunam-1 NPK with spraying three times with 2 ml.l-1 of organic fertilizer (Humic acid), which improved the characteristics of vegetative growth and gave the highest rate of mustard number. Plant-1 and number of seeds. Mustard-1 and seed weight. Plant-1 and the amount of seed yield per dunum. application of 45 ppm humic acid with 60/kg – per dunum (per 2500 square meters) would be the best option to maintain better growth, yield and quality in black mustard.
Speakers
KA

Keefah AL-Garallaa

Mississippi State University
Wednesday September 25, 2024 1:00pm - 1:10pm HST
South Pacific 2

1:00pm HST

POM 2 - Deciphering the Proline-Mediated Flowering Delay Mechanism in Peach through Physiological and Metabolic Analyses
Wednesday September 25, 2024 1:00pm - 1:10pm HST
Freezing temperatures can harm peaches in late spring with advanced flowering due to climate change and consequently reduce their yield. Flowering delay is a prominent strategy employed to avoid such spring frost damage. Our previous study demonstrated that treatment with 5% sodium alginate 100 mM CaCl 2 (5AG) can delay the blooming, potentially avoiding frost damage. To elucidate the precise mechanism of flowering delay induced by 5AG in peaches, this study systematically and experimentally analyzed the changes of amino acid profiles in control and 5AG-treated peach plants at different day intervals (0, 1, 2, 11, 21, 25, and 28 DAT). Our findings revealed that the levels of arginine (Arg), glutamate (Glu), and proline (Pro) differed significantly between control and 5AG- treated peach shoots throughout the phenological development of flower buds. Furthermore, Arg and Glu amino acids, are involved in the Pro pathway. Computational metabolomics analyses identified the Pro metabolism related genes and their attributes, gene ontology, gene synteny and gene organizations, which represent diverse biological function of these genes, including flowering responses. In addition, qRT-PCR analysis results revealed that elevated expression of P5CS and P5CR genes, involved in Pro metabolism, led to increased Pro content in control plants. Conversely, 5AG treatment downregulated these genes, resulting in lower proline content. This result suggests that 5AG treatment may restrain gene expression related to Pro accumulation, thereby controlling Pro biosynthesis. In addition, our findings unveiled a direct connection between Pro content reduction and delayed flowering. Taken together, these results provide strong evidence that 5AG treatment significantly delays flowering by controlling Pro metabolisms in Prunus persica.
Speakers
avatar for HYUNSUK SHIN

HYUNSUK SHIN

Gyeongsang National University
Co-authors
JH

JAE HOON JEONG

Gyeongsang National University
NA
MP

MUTHURAMALINGAM PANDIYAN

Gyeongsang National University
NA
SH

Seung Heui Kim

Korea National College of Agriculture and Fisheries
NA
YP

YEONJU PARK

Gyeongsang National University
NA
Wednesday September 25, 2024 1:00pm - 1:10pm HST
Coral 2

1:00pm HST

VCM 2 - Field Screening of Cabbage (Brassica oleracea var. capitata) Cultivars for Resistance to Black Rot
Wednesday September 25, 2024 1:00pm - 1:10pm HST
One of the most effective management strategies for controlling black rot (Xanthomonas campestris pv. Campestris (Xcc)) in cabbage (Brassica oleracea var. capitata) is resistant cultivars. The objectives of this research were to evaluate commercial and experimental cabbage cultivars for black rot resistance and determine yield potential, harvest maturity, and head quality. A field experiment with nine cultivars (1488, Capture, Celebrate, Cheers, Expat, Melissa, TCA-576, TCA-606, and TCA-607) was carried out during the fall season of 2023 at Hort Hill research farm on the University of Georgia, Tifton campus. ‘Cheers’ (commonly grown high-yielding cultivar), ‘Capture’, and ‘Expat’ (claims high resistance to black rot), and ‘Melissa’ (black rot susceptible Savoy cabbage) were used as checks for comparison with other F1 cabbages. Plants were spray-inoculated with Xcc (250 ml of 10^6 CFU/ml) at 5 and 7 weeks after transplanting. Treatments were arranged in a randomized complete block design with four replications. Relevant agronomic practices, such as irrigation, fertilization, and insect management, were implemented uniformly across all plots. Black rot severity was rated using a 1-9 scale, where 1 indicates the most resistant and 9 represents the least resistant (most susceptible) cultivar. The trial was harvested four times on the following dates:11/30/2023, 12/12/2023, 12/20/2023, and 01/03/2023. Black rot severity, total head counts and weights; and average head weight and height: and average core height, and width were statistically significant between treatments. ‘TCA-607’ and ‘Capture’ had the highest resistance to black rot disease, while ‘1488’ was the most susceptible. All other cultivars expressed moderate levels of resistance. In the first harvest ‘Cheers’ and ‘TCA-607’ had the highest total marketable head counts and weights, indicating early maturity. In addition, ‘Cheers’ and ‘TCA-607’ cabbage had the highest total marketable head counts and weight, followed closely by ‘TCA-606, ‘Celebrate’, and ‘1488’. ‘Cheers’ and ‘TCA-607’ had the highest average head height. Furthermore ‘TCA-607’ outperformed all the cultivars for the average head weight. Among all the cultivars ‘Melissa’ and ‘Expat’ performed the worst for total marketable counts and weights. Overall based on our trial, the experimental cultivar ‘TCA-607’ has the best combination of traits: best black rot resistance, highest yields, and biggest heads.
Speakers
MK

Manisha Kumari

Post-Doctoral Research Associate AD, The University of Georgia
Manisha Kumari is a post-doctoral research associate AD at Horticulture department, University of Georgia, Tifton campus, Tifton 31793, GA, USA.
Co-authors
TM

Ted McAvoy

University of Georgia
NA
Wednesday September 25, 2024 1:00pm - 1:10pm HST
South Pacific 3

1:00pm HST

PB 2 - RNA-seq Analysis Reveals Differentially Expressed Genes in Sweetpotato cv. Beauregard under Lead Stress
Wednesday September 25, 2024 1:00pm - 1:15pm HST
Lead (Pb) is a widespread toxic element in agricultural soils and Pb accumulation in plant roots represents a potential health risk for human beings. The sweetpotato (Ipomoea batatas L.) is a globally important root crop and one of the leading raw products for baby food processing. Limited information is available about the mechanism by which sweetpotato responds to Pb stress at the molecular level. Understanding the genetic mechanism of Pb uptake is essential for developing management approaches to mitigate Pb uptake in this crop. To address this knowledge gap, RNA-seq was used to characterize the transcriptome and identify differentially expressed genes from Pb-treated and untreated sweetpotato cv. Beauregard. Samples were taken from adventitious root tips at 5, 10, and 15 days after planting (DAP). Transcriptomic analysis revealed 4,077, 5,159, and 3,206 differentially expressed genes at 5, 10, and 15 DAP respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis shows that ABC transporters and sulfur metabolism pathways are upregulated at 5 DAP but are downregulated at 15 DAP, indicating that there may be a threshold in sweetpotato Pb tolerance. The results provide a deeper insight into the species-specific response of sweetpotato to Pb stress which can lead to the development of screening methods and evaluation of management strategies that reduce Pb uptake in this crop.
Speakers
MA

Mary Ann Munda

Louisiana State University
Co-authors
AV

Arthur Villordon

LSU Agcenter
DL

Don La Bonte

Louisiana State Univ
NA
LA

Lisa Arce

Louisiana State University
MA

Mae Ann Bravo

Louisiana State University
MB

Marissa Barbosa

Lousiana State University
Wednesday September 25, 2024 1:00pm - 1:15pm HST
South Pacific 4

1:05pm HST

FLOR - Investigating the Effect of Hydrafiber and Biochar As a Substitute for Peat-based Substrate for Zinnia (Zinnia elegans)
Wednesday September 25, 2024 1:05pm - 1:15pm HST
The increasing environmental concerns and economic pressures necessitate the search for peat moss alternative as a substrate component, aiming to balance ecological sustainability with cost-effectiveness. This study aims to assess whether the biochar (BC) and hydrafiber (HF) could be a partially replacement for peat moss for zinnia and snapdragon production. Twelve substrates were formulated by either mixing BC (20%,40%, or 60% by vol) with HF (20%, 40%, or 60% (by vol), with the remaining being peat moss or blending BC (0%, 20%,40%, and 60%, by vol) with the commercial peat moss-based substrates (CS). The physical properties of substrate, including container capacity (CC), total porosity (TP), air space (AS), bulk density (BD), and water holding capacity (WHC), and chemical properties including leachate pH and electrical conductivity (EC) were measured. Plant growth parameters including growth index (GI) and leave greenness (indicated with SPAD value), biomass, and numbers of flowers were measured biweekly. The results showed all the substrate mixes had similar AP, BD and SPAD. Treatment with 20
Speakers
avatar for Lilin Chen

Lilin Chen

Graduate Research Assistant, University of Georgia
I'm interested in biochar effect on containerized plants, especially the effect under abiotic stresses such as drought and salinity.
Co-authors
PY

Ping Yu

University of Georgia
YC

Yulong Chen

The University of Georgia
Wednesday September 25, 2024 1:05pm - 1:15pm HST
Nautilus 1

1:05pm HST

LOCSY - Fermented Hot Pepper Sauce as a Model for New Value-Added Opportunities for Local Food Production
Wednesday September 25, 2024 1:05pm - 1:15pm HST
Development of value-added products by local growers can lead to additional economic opportunities for small farmers by utilization of unsold crops for production of products. Kentucky State University (KSU) received a USDA Capacity Building grant to create a Fermentation and Distillation Sciences Program to train students in this area, but also help local farmers develop new value-added fermented products. There are many job opportunities either supporting or directly involved in the fermentation and distillation sciences in Kentucky and the surrounding region. The goal of the program is to develop new recipes for value-added products for small-scale producers, including pawpaw, hemp, and sorghum beer and kombucha, spirits, and fermented fruit and vegetable products through research supported by new equipment. Hot pepper sauce is of great interest to small producers since it is fairly easy to make and there are many variations in recipes. The objective of this current study was to develop new recipes for fermented hot pepper sauce as new value-added products for small-scale producers. Pepper plantings were established at the Kentucky State University Harold R. Benson Research and Demonstration Farm for a range of pepper cultivars including: Shishimai (Shishito Pepper), Sargento (Poblano Pepper), Bottle Rocket (Cayenne Pepper), Mad Hatter (Bishop's Crown Pepper), Roulette (Habanero Pepper), Helios (Habanero Pepper), Carmen (Corno di Toro Pepper), and a number of other peppers over a three year period. Initially, a number of recipes for fermented hot pepper sauce were evaluated and subject to taste trails. These recipes varied in preparation, pepper type, and vinegar addition. Finally, a potential unique fermented hot pepper sauce was developed that would be of interest to local farmer to produce as a value added product. A tasting trail was conducted with 23 individuals on the KSU campus comparing this new recipe to three commercially available hot sauces. There were 14 males and 8 female participants, with 1 participant preferring not to answer. The average age range was between 26 and 45. Hot sauce samples were served on saltines and evaluated from 1 to 5 for color, smell, flavor, heat, and willingness to pay. The individuals were also asked to rank their favorite sauce. Additional data was collected concerning the participants liking of spicy foods. The fermented hot pepper sauce recipe that was developed was well received and should be of interest for production by local farmers.
Speakers
MB

Matthew Behrends

Kentucky State University
NA
Co-authors
JL

Jeremy Lowe

Kentucky State University
JN

Joni Nelson

Kentucky STate University
KP

Kirk Pomper

Kentucky State University
Dr. Kirk W. Pomper is the Professor of Horticulture in the College of Agriculture, Community, and the Sciences at Kentucky State University in Frankfort, Kentucky. As Horticulture Research Leader, his program is focused on research and Extension efforts toward developing pawpaw as... Read More →
SC

Sheri Crabtree

Kentucky State University
Wednesday September 25, 2024 1:05pm - 1:15pm HST
South Pacific 1

1:10pm HST

CE - Effects of Short-Wavelength UV-B, UV-A, and Blue Light on the Rose Flower Color Transition Phenotype
Wednesday September 25, 2024 1:10pm - 1:20pm HST
Light quality plays a crucial role in the growth and development of plants. In this study, we aimed to assess the effects of short-wavelength light on rose genotype '16401-N055’, which exhibits the flower color transitioning trait: the flowers change colors from yellow to pink in sunlight. Roses that exhibit this flower phenotype are termed transitioning-type roses. Specifically, we analyzed and compared the impact of six different light treatments [a sunlight control in open field and five spectral treatments created using light-emitting diodes (LEDs)] on various physiological and morphological characteristics. The five LED treatments included white light, blue light, UV-A white light, UV-B white light, and 80% blue 20% white light. Each treatment had two replications where one-year-old rose plants were the experimental unit. The total light intensity was maintained at 300-350 micromol m-2 s-1 for a photoperiod of 16 h light and 8 h darkness. The morphological traits measured included height, width, number of buds, number of flowers, and node density. The color scale parameters L* [luminance of the color ranging from 0 (black) to 100 (white)], a* [red (positive values) and green (negative values) color levels], and b* [yellow (positive values) and blue (negative values) color levels] were measured using a colorimeter. Additionally, the chlorophyll concentration index (CCI) was measured using a chlorophyll meter. Fully pigmented pink flowers were only observed in the UV-B white light treatment with an average L* value of 44.1 and a* value of 50.6. A slight pink hue was observed on the outer sections of petals in blue and blue white light treatments. The average L* and a* values of flowers in the blue treatment were 87.21 and 6.24, and in blue white treatment were 90.9 and 1.86, respectively. The flowers in the white UV-A treatment remained white with the highest average L* value of 92.4 and the lowest average a* value of -1.86. The CCI of plants under sunlight (23.5) was significantly lower than the plants treated with blue (34.4), and blue white (33.7) light. No significant differences in morphological traits were detected after two weeks. The plants will be monitored for longer periods and more data will be collected every two weeks for one month to document additional changes. The results obtained will provide additional information on morphological and floral changes in this genotype under different light treatments.
Speakers
NK

Navdeep Kaur

Texas A and M university
Co-authors
DB

David Byrne

Texas A and M University
NA
OR

Oscar Riera-Lizarazu

Texas A and M University
NA
SZ

Shuyang Zhen

Texas A and M University
NA
Wednesday September 25, 2024 1:10pm - 1:20pm HST
Coral 1

1:10pm HST

HSMP - Assessment of micropropagated ginger cultivars and generations on plant growth and rhizome yield in a greenhouse
Wednesday September 25, 2024 1:10pm - 1:20pm HST
Our research demonstrated micropropagated ginger helped solve seed ginger sourcing issue for this “niche” market crop. Traditionally, farmers would save ginger rhizomes from the previous year’s harvest, store over winter, and then use as seeds for the upcoming growing season. This research was to determine if micropropagated ginger generations would affect ginger growth and yield. We studied nine ginger cultivars (BB, BG, BK, CW, HY, MD, PY, KY, and KM) from various tissue culture (TC) generations (TCF1, TCF2, TCF3, and TCF4). TCF1 seedlings were initially planted (March 2023), and then transplanted with TCF2, TCF3 and TCF4 from previous years’ study, into individual grow bags (May 2023) with one seedling per 10-inch grow bag (2:1 metro mix:compost). Plants were placed on a bench inside a greenhouse with a completely randomized design (CRD) with 20 cultivar/TC Generation combinations, 5 replications per cultivar/generation. We collected growth data (stem number, diameter, length, and SPAD), yield data (number of rhizome pieces per seedling, weight of individual rhizome piece/finger, weights of biological root, edible root and total rhizome weight), and PAR of individual plants. Data was then analyzed using SAS OnDemand for Academics with PROC GLM at the 0.05 level of significance. There was a significant effect as the number of TC generations increased, with stem length (TCF1 – 91.8, TCF2 – 91.0, TCF3 – 103.5, and TCF4 – 101.5 cm) and stem diameter (TCF1 – 6.2, TCF2 – 6.4, TCF3 – 8.1, and TCF4 – 8.1 mm) increasing, while number of stems (TCF1 – 19.0, TCF2 – 18.3, TCF3 – 10.4, and TCF4 – 9.9) decreased on average. TC generations had significant effect on rhizome yield. Individual pieces of ginger rhizome decreased in number (TCF1 – 37.9, TCF2 – 31.1, TCF3 – 28.9, and TCF4 – 28.0) but increased in size (weight) (TCF1 – 12.3, TCF2 – 16.8, TCF3 – 25.4, and TCF4 – 23.1 g) as number of TC generations increased. Similarly, biological root weight significantly decreased (TCF1 – 175.9, TCF2 – 195.3, TCF3 – 42.0, and TCF4 – 52.9 g). Edible root weight significantly increased (TCF1 – 443.9, TCF2 – 460.6, TCF3 – 700.6, and TCF4 – 641.0 g). There was a slight upward trend of rhizome yield as TC generations increased (TCF1 – 619.9, TCF2 – 671.3, TCF3 – 761.2, and TCF4 – 709.5 g).
Speakers Co-authors
DT

Daniel Tetteh

North Carolina A
NA
JR

Julia Robinson

North Carolina A
NA
WL

William Lashley

North Carolina A
NA
ZM

Zipporia Moore

North Carolina A
NA
Wednesday September 25, 2024 1:10pm - 1:20pm HST
South Pacific 2

1:10pm HST

POM 2 - Genetic Architecture of Important Traits for Prunus Crop Improvement
Wednesday September 25, 2024 1:10pm - 1:20pm HST
Numerous QTL and GWAS studies have been conducted on various species of Prunus, but there is limited knowledge on the overall genetic architecture regulating fruit quality traits among these species. As part of a 2022-funded SCRI- project to advance database resources for specialty crop research, efforts are directed towards collecting and curating all types of big data in the Genome Database for Rosaceae (www.rosaceae.org). We conducted an extensive literature review on over 120 QTL and GWAS studies on Prunus traits to extend the existing data in GDR. We aligned the traits to the peach genome to compare important traits in various Prunus species. The consensus map showing QTL hotspots will be accessible using various tools in GDR. Implications of the newly created resources and tools in GDR for breeding will be discussed.
Speakers
MI

Michael Itam

Clemson University
Co-authors
CH

Chun Huai Cheng

Washington State University
NA
DM

Dorrie Main

Washington State University
JY

Jing Yu

Washington State University
NA
JH

Jodi Humann

Washington State University
KB

Katheryn Buble

Washington State University
NA
KG

Ksenija Gasic

Clemson University
PZ

Ping Zheng

Washington State University
NA
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
Wednesday September 25, 2024 1:10pm - 1:20pm HST
Coral 2

1:10pm HST

VCM 2 - Evaluation of Brassica Oleracea Genotypes in Terms of Agronomic Performance
Wednesday September 25, 2024 1:10pm - 1:20pm HST
Plant growth performance of 35 different broccoli cultivars was assessed during the Fall season 2023 in terms of plant growth and head development in SW Florida. In particular, seeds of Brassica oleracea var. italica genotypes that were obtained from USDA, ARS, Plant Genetic Resources Unit (PGRU)
Speakers
ST

Sotirios Tasioulas

SWFREC - University of Florida/IFAS
Co-authors
JW

Jessie Watson

SWFREC - University of Florida/IFAS
NA
PT

Pavlos Tsouvaltzis

Southwest Florida Research and Education Center, University of Florida
NA
TL

Tie Liu

University of Florida
NA
Wednesday September 25, 2024 1:10pm - 1:20pm HST
South Pacific 3

1:15pm HST

FLOR - The Impact of Cold and Darkness on Osmanthus fragrans Flowering and Growth
Wednesday September 25, 2024 1:15pm - 1:25pm HST
Osmanthus fragrans, a culturally and economically significant plant in Asian countries, exhibits unique floral characteristics influenced by endogenous metabolites. Previous studies suggest its flowering timing and intensity may be affected by environmental factors including cold and darkness. This study aimed to investigate the effects of cold and darkness factors on the response of Osmanthus fragrans flowering and growth. This experiment included 7 cold and dark treatments (plants were sitting in the dark coolers from 0-15 days) and dark-only treatments (plants were sitting in the GH with plastic bags from 0-9 days). Plant responses were assessed based on the number of flowers, height, and width measurements on the 5th, 7th, 9th, 11th, 13th, and 15th days post-treatment. The results showed there was no significant difference in plant height across treatments. Dark-only treatment for 7 days significantly increased width growth compared to the control group (9 days), and dark-cold treatment for 5, 7, 9, 11, and 13 days. The increase in the number of flowers in the cold-dark treatment for 9 and 15 days was significantly higher than in other treatments, except for the control. In conclusion, the cold and darkness could promote flowering in Osmanthus fragrans without negatively affecting plant growth.
Speakers
avatar for Yulong Chen

Yulong Chen

The University of Georgia
Co-authors
LC

Lilin Chen

The University of Georgia
NA
PY

Ping Yu

University of Georgia
Wednesday September 25, 2024 1:15pm - 1:25pm HST
Nautilus 1

1:15pm HST

LOCSY - The Missouri Produce Growers Video Newsletter – Digestible, Accessible and Impactful Extension Education
Wednesday September 25, 2024 1:15pm - 1:25pm HST
The Missouri Produce Growers Video Newsletter (MPGVN) was established in 2020, when the COVID-19 pandemic prevented in-person programming. The MPGVN is a bi-weekly video-based email newsletter targeting specialty crop farmers and is an offshoot of a project consisting of weekly live-streamed remote educational town halls, which lacked sufficient attendance to justify continuation. Maintaining impactful, ongoing digital engagement with extension audiences is challenging due to grower’s time constraints and competition with low time-investment and high reward non-extension educational media, such as video hosting and social media platforms. The 3–5-minute narrated PowerPoint™ presentations and live shot videos comprising the educational content in the MPGVN, are easily consumed, introducing key points on a timely cropping systems or farm management topic, with further topic resource links embedded. The MPVGN also features links to workshops, grants, and partner agency and non-profit resources. The core team of content contributors, 5 University of Missouri Extension Field Specialists in Horticulture, meets bi-weekly to plan content. Additional extension collaborators from various disciplines including agricultural business, natural resources, climatology, plant pathology, entomology, and food safety contribute content. The newsletter is created and distributed using the Dotdigital™ platform. The format and content have driven engagement amongst the 950 subscribers. The MPGVN engagement metrics relative to industry benchmarks for educational email newsletters are higher by 188% for unique opens, 345% for unique clickers, and 177% for click-to-open rate. To measure the impact of the MPGVN, a survey was sent to 948 subscribers in 2023, with a 14% response rate. Survey observations showed that 55% identified as growers “currently growing and selling produce or planning to grow and sell produce”, 45% as extension educators, and 5% as home gardeners. The survey showed that of the growers; 85% indicated knowledge gains; 78% reported adoption or change of farming practices ; 63% attended an extension class ; 56% connected with a partner agency ; 23% applied to grants ; and 10% received grant awards, thanks to information delivered in the newsletter. The MPGVN is a valuable educational tool, driving engagement with extension programming and resources.
Speakers
avatar for Justin Keay

Justin Keay

MU Extension
Justin Keay has served as a Field Specialist in Horticulture with University of Missouri Extension since 2018, and is currently based in Pike County, MO. He holds a bachelor’s degree in Environmental Studies from Washington University, and an M.S. in Integrated Agricultural Systems... Read More →
Wednesday September 25, 2024 1:15pm - 1:25pm HST
South Pacific 1

1:15pm HST

PB 2 - RNASeq Analysis Reveals Key Pathways Involved in Low Nitrogen Tolerance at the Onset of Storage Root Formation in Sweetpotato cv Bayou Belle
Wednesday September 25, 2024 1:15pm - 1:30pm HST
Nitrogen (N) is a key limiting macronutrient for crop growth and development and affects sweetpotato storage root formation and yield potential. In high-input production areas, excessive N application can suppress storage root formation and results in environmental pollution. The crop is also grown in low-input production systems with little or no N applications. In this study, sweetpotato cv Bayou Belle response to N deprivation during the establishment and storage root formation stages was investigated through a transcriptomic approach. RNA-seq data revealed a number of differentially expressed genes (DEGs) between N sufficient ( N) and N deficient (–N) conditions at 5, 10, and 15 days after planting (DAP). The number of significantly upregulated genes varied between timepoints. DEGs were further classified into functional categories and pathways to reveal putative functions. Gene Ontology annotation together with KEGG analysis revealed that majority of the DEGs are involved in sulfur compound metabolic process at 5 DAP and in ammonium transport for both 10 DAP and 15 DAP. These results provide valuable insights about the molecular mechanism of N regulation in sweetpotato adventitious roots undergoing storage root formation. These findings can lead to the development of tools and processes for improving N use efficiency and consistent storage root yields while reducing environmental impact in this globally important crop.
Speakers
LA

Lisa Arce

Louisiana State University
Co-authors
AV

Arthur Villordon

LSU Agcenter
CG

Cole Gregorie

LSU AgCenter
NA
DL

Don La Bonte

Louisiana State Univ
NA
MA

Mae Ann Bravo

Louisiana State University
MB

Marissa Barbosa

Lousiana State University
Wednesday September 25, 2024 1:15pm - 1:30pm HST
South Pacific 4

1:15pm HST

Writing Letters of Recommendation
Wednesday September 25, 2024 1:15pm - 1:45pm HST
People in academics and in the industry are regularly asked to write letters of recommendation for students, or even employees.  Writing recommendation letters is generally not something people learn or get formal guidance about.  And it’s not something that graduate students typically learn in their degree program. Undoubtedly, many members of our industry and profession will have (student) requests for a support letter for a scholarship, internship, employment, promotion, etc.  Based on personal experience reviewing hundreds of scholarships and award applications for several programs, this presentation will provide insight to assist in writing effective letters of recommendation. Providing a quality recommendation requires thought and effort to enhance the requestor’s success. Specific items a recommender should consider when crafting a recommendation ideally would include obtaining the person’s current resume; a copy of the scholarship or opportunity they are applying to so the nominator can specifically address and connect the individual to the opportunity; specific details including when the recommendation is needed, format required, etc.  Things to consider in the nomination letter include specific relationship to the individual; anecdotes with the particular person that can set the candidate apart; relevant industry/work experiences; awards, recognitions, and involvements, especially if they are not always included in the resume.  Authors should avoid letters that are too long, or too short, and adhere to any limitations outlined by the request. Avoid simply repeating or rehashing the student’s resume, instead provide more detailed insight and praise related to specific resume items.  Sometimes sharing the letter with the student can be appropriate.  It provides an opportunity for them to express concern for something that the author might have over-represented or, perhaps add something the author did not include that could increase impact.  Moreover, the letter is form of feedback and can foster a growth mindset and has the potential to enhance the student’s performance. Additionally, this activity should and can be documented for a faculty performance review.  Writing letters can be time consuming and rewarding, both for the nominee and yourself.  Hopefully insight shared will assist individuals with constructing quality support letters and recommendations.
Speakers
CT

Chad T. Miller

Assistant Professor; Department of Horticulture and Landscape, Colorado State University
Wednesday September 25, 2024 1:15pm - 1:45pm HST
Coral 5

1:20pm HST

CE - Arduino Uno Can Reliably Log Substrate Moisture from a Bus of Digital Sensors and Control a Drip-Irrigation System
Wednesday September 25, 2024 1:20pm - 1:30pm HST
Inexpensive Arduino microcontrollers can be programmed to operate and log data from environmental sensors and operate other accessories such as irrigation solenoids. We describe our efforts to build a modified version of Arduino Uno systems previously developed at the University of Georgia, which operated analog moisture sensors and opened solenoid valves to drip emitters when moisture fell below user-defined thresholds. We attempted to 1) replace analog sensors with a bus of digital sensors that use the SDI-12 communication protocol, 2) include programming to parse digital output from two popular SDI-12 sensors (Decagon GS3 and Campbell Scientific 5TM), 3) use 12VDC solenoid valves that were less expensive and smaller (1/2”) than alternatives, and 4) overcome several challenges encountered in the construction and programming of the Arduino-based system. These included an approach to more easily manage the connection of numerous wires, the inclusion of a reversed diode at the solenoid terminals to prevent electrical interference from intermittently resetting the Arduino program, and the adoption of programming strategies to work around memory limitations that initially rendered our Arduino systems with digital sensors unreliable. We overcame these challenges to develop a robust, reliable, and easy-to-deploy Arduino-based environmental logger and automated drip-irrigation system that can operate numerous digital sensors. Sensor type and thresholds for volumetric water content are defined in a single location within the program, enabling the user to easily make minor adjustments to the system. We also included extensive line-by-line documentation of the source code. A list of the hardware used in this system is available. In 2023, eight of these systems operating 64 total sensors proved their reliability over a two-month experiment on the drought stress physiology of wetland shrubs. We conclude that this system is an effective solution for in-house sensor-automated irrigation with high customizability for end users.
Speakers
SE

Stephanie E. Burnett

University of Maine
NA
Co-authors
AJ

Adam J. Peterson

Unaffiliated
NA
BP

Bryan Peterson

University of Maine
JH

Jessica Hutchinson

University of Maine
RS

Rhuanito S. Ferrarezi

University of Georgia
NA
Wednesday September 25, 2024 1:20pm - 1:30pm HST
Coral 1

1:20pm HST

POM 2 - Taste Acidity and Other Important Fruit Characteristics of New Peach Varieties Compared with Concurrent Varieties During
Wednesday September 25, 2024 1:20pm - 1:30pm HST
Three new peach varieties and ‘Felicia’ ‘Evelynn’ and ‘Anna Rose’ were recently released from the Rutgers University tree fruit breeding program. These varieties are concurrent with some of the standard peach varieties. The comparison of taste acidity and other important fruit characteristics could help growers choose in case of planting these varieties or replacing the standard varieties during the same harvest window. Fruit characteristics such as flesh color, crop load, shape, skin color, fuzz, attractiveness, stone characteristics (free, semi-free, or cling), flesh color, bacterial spot, on fruits and leaves, taste acidity, juice total soluble solids (TSS) concentration (°Brix), and total titratable acidity (TTA) (%) were measured. Here we compare these varieties to highlight the differences and challenges amongst these varieties on their path to full consumer appreciation. Results indicate that average TSS and firmness were higher in ‘Felicia’ (12.9 brix; 12.4 lb) and ‘Evelynn’ (11.9 brix; 10.9 lbs.) compared to ‘Redhaven’ (11.1 brix; 8.14 lbs.). Also; average TSS and firmness were higher in ‘Anna Rose’ (14.4 brix; 13.68 lbs.) compared to ‘Klondike’ (12.0 brix; 11.3 lbs.) and ‘White Lady’ (10.9 brix; 9.64 lbs.). In summary, new yellow-fleshed peach varieties ‘Felicia’ and ‘Evelynn’ have great potential to replace the old standard variety, ‘Redhaven’. Similarly, the new white-fleshed peach variety ‘Anna Rose’ has great potential to replace old standard varieties ‘White Lady’ and ‘Klondike’.
Speakers
HG

Hemant Gohil

Extension AgentII/Associate Professor, Rutgers Cooperative Extension
Co-authors
DW

Daniel Ward

Rutgers University
NA
Wednesday September 25, 2024 1:20pm - 1:30pm HST
Coral 2

1:20pm HST

VCM 2 - Evaluation of Vegetable Soybean Adaptations to South Florida’s Tropical Climate
Wednesday September 25, 2024 1:20pm - 1:35pm HST
Vegetable soybean, also known as edamame, is a specialty crop harvested at an immature stage and consumed as pods. It has become increasingly popular in the United States due to its high nutritional value and good taste. Currently, most edamame consumed in the U.S. is imported as a frozen product. States such as Arkansas and Kentucky have started to grow this crop locally on a small scale to meet the high demand. South Florida, known for producing fresh vegetables sold nationwide, especially in the winter and spring markets, also has a highly diverse and growing ethnic population with significant local market potential. These factors make growers in South Florida highly interested in cultivating edamame to meet the demand in both national and local markets. Sixteen commercial edamame varieties were selected and assessed for differences in phenotypic performance, including emergence, yield, plant height, plant width, 10-pod weight, and pod size, to evaluate their production potential in South Florida. Varieties showed significant effects on most traits studied. Emergence rates ranged from 0 to 85%, and fresh pod yield ranged from 4.41 to 14.34 t/ha among all 16 varieties. Varieties like Goo, Karikachi #3, and Midori Giant, despite having moderate emergence rates, produced higher fresh pod yields due to their larger plants, resulting in bigger pods. There were variations in average pod length (35.61 – 51.21 mm), width (9 - 14 mm), and thickness (5.46 - 8.74 mm) among the varieties, with Goo standing out significantly in size. Overall, Goo, Karikachi #3, and Midori Giant demonstrated particularly favorable yield and good pod quality, showing potential for commercial edamame production in South Florida. This research highlighted the potential to grow edamame in higher hardness zone,  providing foundational knowledge on edamame production in the US.
Speakers
XL

Xiaoying Li

University of Florida, IFAS
Co-authors
Wednesday September 25, 2024 1:20pm - 1:35pm HST
South Pacific 3

1:25pm HST

FLOR - Growth and Quality of Four Zinnia Cultivars Grown in Eastern South Dakota
Wednesday September 25, 2024 1:25pm - 1:35pm HST
Over the past two decades, interest in local specialty cut flower production in Eastern South Dakota has grown with several new flower farms being established across the region. However, there is currently no local, research-based information available to support growers in this new wave of interest. The purpose of this study was to assess the production and quality of four zinnia cultivars grown in Eastern South Dakota to support local specialty cut flower growers in their operations. This was a randomized complete block study with four zinnia cultivars (Zinderella Peach, Oklahoma Ivory, Queen Red Lime, and Benary’s Giant Purple) grown in 2022 and 2023. Zinnias were started in the greenhouse and then transplanted into the field in early summer each season. Harvest began each year when flowers reached maturity (July), with one harvest event taking place each week until the first frost. Harvested flowers were rated as marketable or non-marketable based on categories of stem length (18 -inch-long, 13-17.99-inch-long, 8-12.99-inch-long, and
Speakers
KL

Kristine Lang

South Dakota State University
Co-authors
AB

Alexis Barnes

South Dakota State University
NA
EF

Ellen Fitzpatrick

South Dakota State University
NA
HV

Hannah Voye

South Dakota State University
Wednesday September 25, 2024 1:25pm - 1:35pm HST
Nautilus 1

1:25pm HST

LOCSY - The Center for Sustainability of Farms and Families: Impacts of The Small Scale Farm Grant on Local Foods in Kentucky.
Wednesday September 25, 2024 1:25pm - 1:35pm HST
The Center for Sustainability of Farms and Families: Impacts of The Small Scale Farm Grant on Local Foods in Kentucky. JONI NELSON*, MATTHEW BEHRENDS, ALLISON NOEL, and KIRK W. POMPER. College of Agriculture, Health, and Natural Resources Cooperative Extension Program, Kentucky State University, Frankfort, KY 40601 Kentucky State University’s Small Farm Grant Program managed through the Center for Sustainability of Farms and Families supports new economic opportunities for limited resource farmers with funding from the Kentucky Agricultural Development Board and the USDA-NIFA capacity building grant “Extension Approaches to Support Socially Disadvantaged Farmers and Producers”. The Small Farm Grant Program, which began in 2012, has awarded more than $8.5 million through 1,976 applications to farmers from 114 Kentucky counties. This funding has been distributed through mini-grants for categories including Value-Added, Organic, Aquaculture, Food Insecure, and Agroforestry projects. New categories added in 2024 including Food Systems Resiliency and Emerging Agricultural Technologies have been added in addition to a beginning beekeeper program in our ongoing efforts to address the diverse needs of Kentucky producers. These new categories support the efforts of producers to implement innovative practices or technologies that enhance sustainability and resource efficiency on the farm. Program funding supports a wide range of needs such as mobile freezer units, pond aerators, canning equipment for fruits and vegetables, tractor implements to support organic crop integrity, goat cheese and soap making equipment, root cellars, equipment for food banks and farmers markets, agroforestry practices, and numerous others. This program has also assisted many new farmers with entering local markets and education toward production methods as well as aiding their efforts to support local economies and cooperative networks.
Speakers
JN

Joni Nelson

Kentucky STate University
Co-authors
KP

Kirk Pomper

Kentucky State University
Dr. Kirk W. Pomper is the Professor of Horticulture in the College of Agriculture, Community, and the Sciences at Kentucky State University in Frankfort, Kentucky. As Horticulture Research Leader, his program is focused on research and Extension efforts toward developing pawpaw as... Read More →
MB

Matthew Behrends

Kentucky State University
Wednesday September 25, 2024 1:25pm - 1:35pm HST
South Pacific 1

1:29pm HST

Vegetable Crops Management 3 (VCM 3)
Wednesday September 25, 2024 1:29pm - 3:30pm HST
Monitoring High Tunnel Soil Temperature Fluxes to Understand Soil Health Implications - Bret Lang
Performance of Semi-Controlled Protective Net House at Farmers’ Field to Make The Year-Round Availability of Quality Vegetables and Higher Benefit Cost - AKM Quamruzzaman
Evaluating The Effect Of Cultivar On Garlic Growth And Yield - Stephen Mensah
Optimizing Butterhead Lettuce Production in a High Tunnel Environment - Alan Walters
Resource Use Efficiency, Yield, and Quality of Amaranth Grown as a Summer Leafy Green in Alternative Soilless Systems - Pradip Poudel
Improving Seed Germination, Seedling Biomass and Drought Tolerance of Microgreens Using Low-temperature Plasma - S Mentreddy
Differential performance of Radicchio cultivars in New Hampshire - Becky Sideman
Comparative Analysis of Biodegradable Mulch Use in Hill-side Strawberry Production - Amrita Mukherjee

Moderator
SM

Stephen Mensah

Graduate Research Assistant, North Dakota State University
Greetings! I'm Stephen Mensah, proud son of Ghana. My journey began with a Bachelor's degree in Agriculture from the esteemed University of Cape Coast, Ghana. Now, I'm embarking on an exciting chapter as a graduate student at North Dakota State University, passionately pursuing a... Read More →
Wednesday September 25, 2024 1:29pm - 3:30pm HST
Kahili

1:30pm HST

CE - Precise Moisture Control Promotes Optimal, Fast, and Uniform Spinach Seed Germination
Wednesday September 25, 2024 1:30pm - 1:40pm HST
Spinach (Spinacia oleracea) is a nutritionally and commercially significant crop grown in controlled environments; however, its seeds are difficult to germinate in soilless culture. Excess moisture in the root zone can inhibit germination and impede seedling establishment. To address this, we conducted an experiment with a randomized complete block design (three replications) to identify the optimal moisture content for spinach ‘Space’ germination. In each of 63 sealed containers, we placed 20 seeds on a double-layered paper towel pre-moistened with varying amounts of reverse-osmosis water. We quantified visible germination percentages daily in response to seven moisture indices [moisture mass ÷ (paper mass moisture mass)] ranging from 50% to 94% over an 11-day period. Air temperature and relative humidity were 22.12 ± 0.02 °C and 34.35% ± 8.80%, respectively. The optimal moisture index was 80%, which resulted in the highest cumulative visible germination percentage (92%, which is close to the labelled 93% on the seed package). Deviating from the optimal moisture index in either direction decreased the germination percentage to 0%–22% and delayed germination by up to 5 days. The response of the cumulative visible seed germination percentage to the moisture index followed a normal distribution. The daily new visible germination percentage peaked on day 3 under most moisture indices; it was 55% under the optimal moisture index and < 24% under the other moisture indices. In conclusion, a moisture index of 80% resulted in the highest germination percentage (92%) and the fastest germination time (2–5 days) in spinach ‘Space’, whereas lower or higher moisture indices caused poorer (0%–67%), delayed, and less uniform germination. Once transplanted, the spinach seeds germinated with this moistened-paper method under the optimal moisture index adapt and perform well in soilless substrates, including rockwool, which is notoriously difficult to germinate spinach seeds in.
Speakers
SM

Shem Msabila

University of Delaware
Co-authors
QM

Qingwu Meng

University of Delaware
Wednesday September 25, 2024 1:30pm - 1:40pm HST
Coral 1

1:30pm HST

POM 2 - Role of Silicon in Peach Water Stress Tolerance
Wednesday September 25, 2024 1:30pm - 1:40pm HST
Water stress in young fruit trees can reduce tree growth and impair future crop productivity. Silicon (Si) has shown a positive effect in mechanisms related to water relations, specifically water uptake and transport, as well as physiological and anatomical changes in leaves of annual plants. These findings suggest that Si could induce adaptive changes that could help trees cope with water deficit. The objective of this experiment was to evaluate the role of Si on water status, sap flow, and gas exchange of young peach trees under water deficit. Two-year-old ‘Julyprince’ peach trees grown under controlled conditions received either 100% (well-watered trees) or 50% (stressed trees) of their crop evapotranspiration needs three times a week. Once trees in the two treatments displayed a difference in water status, Si was applied weekly by foliar spray (0 or 20 mg L-1). The combination of these two factors resulted into a completely randomized factorial design with four treatments. Results showed an interaction between irrigation regime and Si application. Si increased sap flow in well-watered trees and reduced that of stressed trees, although this effect was more significant the day after irrigation. Furthermore, Si significantly improved the water status of trees under water deficit but did not influence that of well-watered trees. These results seem to indicate that the role of Si in improving tolerance to water deficit is temporary and dependent on the tree water status.
Speakers
avatar for Noah Willsea

Noah Willsea

Clemson University
Co-authors
IM

Inma Martos-Garcia

University of Cordoba
NA
JC

Juan Carlos Melgar

Clemson University
NA
MB

Maria Benlloch-Gonzales

University of Cordoba
NA
RF

Ricardo Fernandez-Escobar

University of Cordoba
NA
Wednesday September 25, 2024 1:30pm - 1:40pm HST
Coral 2

1:30pm HST

PB 2 - Introducing CHiDO – a No Code Genomic Prediction Software implementation for the Characterization & Integration of Driven Omics
Wednesday September 25, 2024 1:30pm - 1:45pm HST
Climate change represents a significant challenge to global food security by altering environmental conditions critical to crop growth. Plant breeders can play a key role in mitigating these challenges by developing more resilient crop varieties; however, these efforts require significant investments in resources and time. In response, it is imperative to use current technologies that assimilate large biological and environmental datasets into predictive models to accelerate the research, development, and release of new improved varieties. Leveraging large and diverse data sets can improve the characterization of phenotypic responses due to environmental stimuli and genomic pulses. A better characterization of these signals holds the potential to enhance our ability to predict trait performance under changes in weather and/or soil conditions with high precision. This presentation introduces CHiDO, an easy-to-use, no-code platform designed to integrate diverse omics datasets and effectively model their interactions. With its flexibility to integrate and process data sets, CHiDO's intuitive interface allows users to explore historical data, formulate hypotheses, and optimize data collection strategies for future scenarios. The platform's mission emphasizes global accessibility, democratizing statistical solutions for situations where professional ability in data processing and data analysis is not available.
Speakers
DJ

Diego Jarquin

University of Florida
Co-authors
FG

Francisco Gonzalez

University of Florida
NA
JG

Julian Garcia-Abadillo

University of Florida
NA
Wednesday September 25, 2024 1:30pm - 1:45pm HST
South Pacific 4

1:30pm HST

VCM 3 - Monitoring High Tunnel Soil Temperature Fluxes to Understand Soil Health Implications
Wednesday September 25, 2024 1:30pm - 1:45pm HST
High tunnel soil health is crucial for successful and sustainable crop production within protected environments. Soil microbial activity is highly temperature-dependent, and soils that are slightly warmer will foster increased metabolic rates within soil communities enhancing microbial diversity and enzymatic activity, promoting nutrient availability. However, little is understood about the potential for microbial activity during colder seasons in norther latitudes when high tunnels are taken out of production and soils are left fallow. Temperature variation in high tunnels could also create variation in microbial community activity, creating spatial nutrient variation with impacts on production the following season. To analyze soil temperature fluxes, we buried an array of 27 soil sensors four inches deep within the soil in a newly built, 30-foot-wideby 96-foot-long tunnel located in Brookings, South Dakota. The high tunnel was oriented east to west and soil was bare. Soil temperatures were recorded at 30-minute intervals from December 22 to March 15, (2023 – 2024). Air temperature and light (lux) data was also collected inside of the high tunnel as well as external weather data from a nearby (>1km) Mesonet weather station. We used multiple linear regression to model the relationship between average internal soil temperature and internal light and temperature data. We also compared sensor location (latitude, longitude, and Euclidean distance from the center of the high tunnel) on soil temperature within the high tunnel using an ANOVA and multiple linear regression to examine how sensor location was related to soil temperature. Our top model of internal soil temperature showed light, internal temperature, and the interaction between light and internal temperature explained a large amount of high tunnel soil temperature variation (R2 = 0.87, p < 0.0001). There was also significant variation in soil temperature throughout the high tunnel, with the daily mean difference of 3.12 degrees Celsius (p < 0.0001) observed between our sensor at the center of the high tunnel and our sensor near the northwest corner of the high tunnel. Our top model showed that latitude, the quadratic of longitude, and the Euclidean distance from the center of the high tunnel explained a moderate amount of high tunnel soil temperature variation (R2 = 0.44, p < 0.0001). This analysis demonstrates a need to further investigate how microbial communities react to temperature variation within high tunnels when they are not in production.
Speakers
BL

Bret Lang

Student, South Dakota State University
Co-authors
KL

Kristine Lang

South Dakota State University
LP

Lora Perkins

South Dakota State University
NA
Wednesday September 25, 2024 1:30pm - 1:45pm HST
Kahili

1:35pm HST

FLOR - Effects of Photoperiod Treatments on Stock Plants and Cutting Rooting of Callirhoe involucrata
Wednesday September 25, 2024 1:35pm - 1:45pm HST
Effects of Photoperiod Treatments on Stock Plants and Cutting Rooting of Callirhoe involucrata James E. Klett and Ronda Koski Colorado State University Department of Horticulture and LA Production of attractive and desirable plants, native to the plains and prairies of central North America, can sometimes be limited due to problems associated with successful rooting of vegetative cuttings. Species that have a long period of bloom can be challenging to vegetatively propagate during the growing season, because sufficient juvenile (vegetatively) growth is necessary for high-quality cuttings. Callirhoe involucrata (winecups) is a native herbaceous perennial with sprawling stems, palmately divided leaves, and dark pink flowers that creates a long lasting, colorful groundcover in landscapes with limited or no supplemental irrigation. Winecups can be difficult to propagate due to seed dormancy and poor rooting of vegetative cuttings. Manipulating the growing conditions of stock plants to suppress reproductive growth may improve rooting success of vegetative cuttings. Based on previous research at Colorado State University with other ornamental perennials and programmed photoperiods, winecups were grown under three programmed photoperiods to determine if a particular photoperiod could be used to suppress reproductive growth and promote vegetative growth. The research was replicated three times, all conducted in a similar fashion, but at different times of the year. Results indicate that plants grown under 10-hour light and 8-hour light photoperiods remained vegetative longer when compared to plants grown under 12-hour photoperiod. Plants grown under 12-hour photoperiods had greater mean ending dry weight when compared to plants grown under 10 hour and 8-hour photoperiods. Cuttings harvested from plants grown under 8-hour photoperiod had higher percent rooting and greater number of roots per cutting when compared to vegetative cuttings harvested from plants grown under 12-hour photoperiod. Based on these research findings, plant propagators may be able to increase production of winecups by growing stock plants under 8-hour photoperiod.
Speakers
JK

James Klett

Colorado State University
Wednesday September 25, 2024 1:35pm - 1:45pm HST
Nautilus 1

1:35pm HST

LOCSY - The Waimānalo Learning Center: Land-Grant Experiment Stations as a Space to Heighten Community Engagement and Advanceme
Wednesday September 25, 2024 1:35pm - 1:45pm HST
The Waimānalo Learning Center (WLC) is a University of Hawai’i (UH) project established in 2012 through seed funding from the UH College of Tropical Agriculture and Human Resources (CTAHR) and the Harold K.L. Castle Foundation. Located at CTAHR's Waimānalo Research Station, the WLC aims to transform the station into a community learning center that promotes food security, self-sufficiency, and healthy eating, particularly for indigenous and underserved populations. The UH physical facilities supporting WLC include an aquaponics facility and outdoor classroom adjacent to certified organic research plots. A Community Coordinator was added in 2014, and since then the WLC has rapidly expanded its programming through close partnerships with local schools and community organizations. In 2017 the WLC has partnered with a local non-profit, Ke Kula Nui O Waimānalo to run food sovereignty programs including aquaponics (MALAMA), agroforestry (Ulupono Mahi ‘Āina), and backyard egg production (Hui Hua Moa). In a survey of key partners, the vast majority of 75 respondents strongly agreed that: 1) The WLC has been a valuable partner for their organization (98.6%); 2) The WLC plays an important role in serving the Waimanalo community (95.9%); 3) The WLC has helped them elevate their group’s mission and vision (94.5%). Echoing the comments of others, one respondent stated “The Waimānalo Learning Center has served as important ʻāina (land) for our haumana (students) to build pilina (relationship), hana (work), and take on greater kuleana (responsibility) with. The staff and facilities have allowed us to grow and deepen our curriculum of place-based, ʻāina work within our community.” The results from 12 years of activity suggests that the WLC is an effective model for using Land Grant Research Stations to address community needs around food, health and cultural preservation, and increase community engagement and advancement.
Moderator
TR

Theodore Radovich

University of Hawai'i at Manoa, Ke Kula Nui O Waimanalo
NA
Speakers
HI

Heidi Ilima Ho-Lastimosa

University of Hawai'i at Manoa, Ke Kula Nui O Waimanalo
NA
Co-authors
IR

Ikaika Rogerson

Ke Kula Nui O Waimanalo
NA
JC

Jane Chung-Do

University of Hawai'i at Manoa, Ke Kula Nui O Waimanalo
NA
JS

Jari Sugano

University of Hawaii at Manoa
NA
KH

Kenneth Ho

Ke Kula Nui O Waimanalo
NA
KD

Kirk Deitschman

Ke Kula Nui O Waimanalo
NA
LK

LeShay Keliiholokai

Ke Kula Nui O Waimanalo
NA
RF

Richard Fisher

University of Hawai'i at Manoa
NA
Wednesday September 25, 2024 1:35pm - 1:45pm HST
South Pacific 1

1:40pm HST

POM 2 - Mechanization Reduces Pruning and Harvest Labor Time in the Cider Apple Orchard
Wednesday September 25, 2024 1:40pm - 1:50pm HST
While fresh-eating, dessert apples dominate the apple market of Washington State, the over 30-fold national increase in volumetric cider production over the past 15 years indicates there is growing demand for specialty cider apples, or apple cultivars with positive cider-making attributes such as high polyphenol content. In a commercial cider orchard, the labor costs associated with thinning, pruning, and harvest comprise a majority of the annual variable production costs once the orchard is in full production; thus, reducing the labor time to perform these tasks has the potential to increase the appeal and profitability of growing cider apples. Further, when cider apples are pressed into juice soon after harvest, cosmetic damage and bruising of the fruit during harvest has minimal impact on juice quality, indicating a strong potential for harvest mechanization. This study separately examines mechanical hedging and mechanized over-the-row harvest (using a modified Oxbo-Korvan 930 harvester) in a multi-cultivar cider apple orchard. Mechanical hedging both sides of the orchard row occurred at a rate of 2.1-3.5 seconds per meter across 5 years. Across 16 cultivars and 3 years, mechanical harvest occurred at a rate of 2.7-3.1 seconds per meter, and the average capture efficiency was 82% with no significant differences between cultivars. Based on these results, a combination of mechanical pruning and harvest could significantly lower labor time, and thus the total production costs, associated with growing cider apples.
Speakers
CM

Carol Miles

Washington State University
Co-authors
AK

Aidan Kendall

Washington State University
NA
ES

Ed Scheenstra

Washington State University
NA
SB

Seth Brawner

Washington State University
Wednesday September 25, 2024 1:40pm - 1:50pm HST
Coral 2

1:44pm HST

Ecological Physiology/Horticultural Plant Reproductive Biology/Plant Growth Regulation (EcoPhys/HPRB/PGR)
Wednesday September 25, 2024 1:44pm - 2:45pm HST
Multiple Modeling Approaches Reveal Temperature Dependent Germination Traits of Vegetable Varieties - Miro Stuke
Identifying Pollinators Present on Flowers of the Pawpaw Cultivars 'Sunflower' and 'Susquehanna' - Subas Thapa Magar
Characteristics of the Secondary Walls of Xylem of the Tomatoes Cultivated Under Water Deficit - Marcio Mesquita
Molecular Assessment of Heat Sensitivity in Broccoli Flowering - Thomas Bjorkman
Morpho-physiological Response of Plectranthus amboinicus under Flooding and Drought Stress - Samuel Asiedu
Effects of Paclobutrazol, Progressive-raising Temperature and Spike-truncated Treatments on Phalaenopsis Join Grace ‘TH288-4’ - Yi Chien Lu

Moderator
ST

Subas Thapa Magar

Kentucky State University
A major change happened when the tragedy of Corona hit the world. Hi, I am Subas Thapa Magar, a graduate research assistant under the supervisor Dr. Kirk Pomper. I am currently working on Pawpaw (Asimina Triloba), the native fruit tree of the United States of America, and my research... Read More →
Wednesday September 25, 2024 1:44pm - 2:45pm HST
South Pacific 3

1:45pm HST

EcoPhys/HPRB/PGR - Multiple Modeling Approaches Reveal Temperature Dependent Germination Traits of Vegetable Varieties
Wednesday September 25, 2024 1:45pm - 1:55pm HST
Crop seed germination is a critical factor in food production. Germination traits vary between different vegetables and between cultivars of the same vegetable. Traits such as germination proportion and the rate and uniformity of germination also contribute to the success of vegetable cultivars to regional temperature averages and regimes. Temperature is a major abiotic factor in seed germination, and selection of seed varieties suited for local temperatures is important to successful crop establishment. Here we aim to model the germination traits of several Korean and North American vegetable cultivars in relationship to temperature. We hypothesize that a model based on time and temperature will represent germination traits across multiple cultivars and species of vegetable. Additionally, we hypothesize that predicted germination traits will be similar within species but will vary between cultivars of the same species based on the regional temperature norms. Eleven vegetable cultivars including two corn, four radish, two pepper, and three onion, were germinated in growth chambers set at 5°C intervals between 5 and 40°C with a 12 hour photoperiod. Germination, defined by radicle emergence equal to the length of the seed, was monitored and recorded daily. Two modeling approaches were used. 1) A time to event model using the drcSeedGerm package in R was used to determine maximum germination proportion (Pmax), germination rate at 50% germination (GR50), and uniformity. 2) A 12-parameter compartmental temperature and time model was implemented, parameterized, and validated in the Cropbox modeling framework. Results show differing temperature responses in germination traits. Additionally, high uniformity was observed in most varieties within the optimal temperature range. The optimal temperature for germination was broad for the vegetable cultivars tested here, with a rapid decrease in Pmax at high and low temperature extremes, except in onions, which showed high Pmax even at 5°C, and a gradual decline above 25°C. All cultivars showed decreased Pmax at 40°C. A time to event model was able to predict germination traits in several crop species. The compartmental model was better equipped to handle heat induced seed degradation but was less parsimonious for determining germination probability and germination rate related parameters. Modeling crop germination traits can provide important context for selecting appropriate cultivars for local climates. A thermal time to event model and a compartmental model both provide potential frameworks for modeling germination traits of diverse vegetable species.
Speakers
MS

Miro Stuke

University of Washington
Co-authors
AH

Arthur Hsin-Wu Hsu

University of Idaho
NA
KY

Kyungdahm Yun

Jeonbuk National University
NA
SZ

Sabrina Zerrade

University of Washington
NA
SK

Soohyung Kim

University of Washington
Wednesday September 25, 2024 1:45pm - 1:55pm HST
South Pacific 3

1:45pm HST

FLOR - Consumer testing and surveys indicate a market for Peperomia mauiensis, an endemic succulent with potential use as an indoor potted plant
Wednesday September 25, 2024 1:45pm - 1:55pm HST
Peperomia mauiensis is an endemic succulent found on the islands of Maui, Molokai and Lanai. Its reddish stems and foliage as well as its small stature make it a potential indoor ornamental plant. To assess consumer acceptance, a public plant giveaway with surveys was conducted. Fifty-six plants in plastic and ceramic pots were distributed to the public with the completion of a survey. A six-month follow up survey was conducted to assess the condition of the plant and obtain consumer feedback. During the plant giveaway, 77% of participants completed the survey. Nearly all respondents are willing to buy the plant and recommend it to friends and co-workers. Thirty percent of respondents are willing to buy the plant for $5 in a ceramic pot and $3 to $5 for a plastic pot. Six months after the giveaway, 39.5% of initial respondents completed the follow-up survey. About half of the respondents (52.9%) reported the plant was growing healthy and vigorous. The majority of the respondents did not fertilize the plant (81.3%) and did not report any pest (94.1%) and disease (88.2%) issues. Most responded that they liked it as a houseplant (88.2%) and it was easy to maintain (82.4%). Most respondents (35.3%) were willing to buy the plant again for $5. Results of the surveys indicate that there is consumer interest in Peperomia mauiensis as a new native indoor plant.
Speakers
OB

Orville Baldos

University of Hawaii at Manoa
Co-authors
Wednesday September 25, 2024 1:45pm - 1:55pm HST
Nautilus 1

1:45pm HST

VCM 3 - Performance of Semi-Controlled Protective Net House at Farmers’ Field to Make The Year-Round Availability of Quality Vegetables and Higher Benefit Cost
Wednesday September 25, 2024 1:45pm - 2:00pm HST
The study was conducted at two farmers’ fields in Bangladesh viz., Shibpur, Narshingdi (24.050º N Latitude and 90.718º E) and Chowara Bazar, Cumilla (23.408º N Latitude and 91.244º E), during Oct 2021 to Sep 2022. In this study, we evaluated the effects of five types of vegetables, viz., tomato, sweet pepper, cucumber, netted melon, and okra, under a protected polynet house. The cultivation of vegetables in protected conditions using transparent UV poly net houses played a better role in improving quality, advancing maturity, fruit size, and yield and reducing pest and disease infestation. Protected polynet houses allow better utilization of sunlight due to the manipulation of the spectra of radiation reaching the crops, thus promoting physiological responses in plant and fruit development, including leaf area index, chlorophyll and carotenoid content, tissue structure, fruit ripening, and physiological disorders. Under this evaluation, cultivation under UV Poly nethouse was found better in the Cumilla area compared to Narshingdi. There might be differences in management operations by different growers. For all crops, viz., tomato, sweet pepper, cucumber, netted melon, and okra, the production of the Cumilla area was very significant and higher. The Benefit-cost ratio was also higher [Tomato (2.05), sweet pepper (2.53), cucumber (1.42), netted melon (2.63) and okra (1.35) in Cumilla compared to Narshingdi [Tomato (1.75), sweet pepper (1.92), cucumber (1.21), netted melon (2.20), okra (1.22)], the lower BCR is due to the 1st year calculation. So, with UV poly nethouse technology, high value thermos-sensitive vegetables can be commercially grown year-round successfully to produce a safe and quality product, while higher fruit yield/unit area will be achieved in a protected nethouse than in a field.
Speakers
avatar for Dr. AKM Quamruzzaman

Dr. AKM Quamruzzaman

Chief Scientific Officer, Bangladesh Agricultural Research Institute
Dr. AKM Quamruzzaman is serving at the Olericulture Division, Horticulture Research Centre, Bangladesh Agriculture Research Institute, Bangladesh as Chief Scientific Officer. He joined BARI in 1995 as Scientific Officer. As a horticulturist, now he is the Chief breeder of Solanaceous... Read More →
Co-authors
FI

Ferdouse Islam

Bangladesh Agricultural Research Institute
NA
LA

Limu Akter

Bangladesh Agricultural Research Institute
NA
Wednesday September 25, 2024 1:45pm - 2:00pm HST
Kahili

1:50pm HST

Tropical Plant and Soil Science, University of Hawai'i at Manoa
Wednesday September 25, 2024 1:50pm - 2:20pm HST
Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
Wednesday September 25, 2024 1:50pm - 2:20pm HST
Coral 5

1:55pm HST

EcoPhys/HPRB/PGR - Identifying Pollinators Present on Flowers of the Pawpaw Cultivars 'Sunflower' and 'Susquehanna'
Wednesday September 25, 2024 1:55pm - 2:05pm HST
Pawpaw (Asimina Triloba) is a temperate species of tropical Annonaceae plant family native to the United States. They are small to medium-sized deciduous trees that bear unique and flavorful fruit. Pawpaw fruits are used in various culinary products such as jam, bread, ice cream, cookies, and even to produce brandy. Additionally, they contain antioxidants and acetogenins, which are currently being researched for their potential in cancer treatment. Fruit sets may be limited in some cultivars due to pawpaw flowers being protogynous and self-incompatible, blooming at various stages of development from late March to April. Consequently, the role of insects in pollination is crucial for increasing fruit production. To address this gap in research, this study aims to identify the different insect orders that visit both flowering and non-flowering branches of two distinct pawpaw cultivars (Sunflower and Susquehanna), along with their respective abundances. Ten trees from each pawpaw cultivar were selected to investigate the various pollinator types. In a completely randomized design, 40 wire cage traps with tangle trap adhesive were placed on both the flowering and non-flowering branches of each chosen cultivar. After 18 days of the flowering period, the traps were collected, and the insects captured were identified by order and counted. The data were analyzed using R software (R 4.3.2) and subjected to a one-way ANOVA with flower and non-flower of each cultivar, a two-way ANOVA, Least Significant Difference (LSD) means separation, with flowers and cultivars as the treatments. In 2023, ‘Sunflower’ had significantly more Dipterans and total insects (p-value: 0.3373 NS and 0.3740 NS). In comparison, ‘Susquehanna’ had significantly more Coleopterans (p-value: 0.40525 NS), and in ‘Susquehanna’, coleopterans had significantly more in the flower-branch (p-value: 0.0255*) for 2023. Additionally, data for 2024 will also be reported and will include additional data on insects observed inside the female receptive and matured male flowers from each cultivar.
Speakers
ST

Subas Thapa Magar

Kentucky State University
A major change happened when the tragedy of Corona hit the world. Hi, I am Subas Thapa Magar, a graduate research assistant under the supervisor Dr. Kirk Pomper. I am currently working on Pawpaw (Asimina Triloba), the native fruit tree of the United States of America, and my research... Read More →
Co-authors
JL

Jeremy Lowe

Kentucky State University
KP

Kirk Pomper

Kentucky State University
Dr. Kirk W. Pomper is the Professor of Horticulture in the College of Agriculture, Community, and the Sciences at Kentucky State University in Frankfort, Kentucky. As Horticulture Research Leader, his program is focused on research and Extension efforts toward developing pawpaw as... Read More →
SC

Sheri Crabtree

Kentucky State University
Wednesday September 25, 2024 1:55pm - 2:05pm HST
South Pacific 3

1:55pm HST

FLOR - Trials of Low Elevation Tolerant Leucospermum Hybrids on Oahu, HI
Wednesday September 25, 2024 1:55pm - 2:05pm HST
Leucospermum species are temperate climate plants native to South Africa and have restricted production regions in Hawaii limited to elevations of 457 m or higher. This limitation and competition for land has been partially responsible to a decline in Leucospermum production in Hawaii. Agriculture land at lower elevations is more abundant and cheaper, and is an option for growing low elevation tolerant varieties. Breeding programs at the University of Hawaii at Manoa have focused on developing hybrids that will perform to commercial standards for plant growth, yield and quality, and grow at or near sea level. 14 hybrids of Leucospermum were trialed at 152 m elevation on Oahu HI. 10 hybrids exhibited adequate survival and were selected for continued trial. Weahter, plant growth (height and width), flower count, flowering seasonality, and plant health data were collected from 2021-2023. Flower length and quality data, and vase life data were collected in 2024. Average relative humidity was 79%, average monthly rainfall was 3.53 cm, and average temperature was 21.8 C with maximum temperature of 33.4 C and low of 14.2 C. The 10 hybrids all had acceptable fitness at 500’ elevation. Some hybrids showed more fitness than others. Hybrid 602 had the highest overall average health (3.8) and highest total flower count. Hybrids 620 and 626 also showed excellent fitness as well as highest flower counts. While none of the hybrids are considered unfit for production in similar conditions, some did perform less well. Hybrid 88 and Hybrid 633 had the lowest average health at 3.0 followed closely by Hybrids 583 (3.2), 679 (3.3), and 563 (3.3). These varieties also had some of the lowest total flower counts. All of the hybrids in this study are considered potential candidates for release and continued trialing. Future work can include long term trialing of these plants, and trialing at different microclimates across the State.
Speakers
RG

Russell Galanti

Extension Educator, University of Hawaiʻi
Co-authors
AR

Alberto Ricordi

University of Hawaii at Manoa
KL

Kenneth Leonhardt

University of Hawaii at Manoa
NA
Wednesday September 25, 2024 1:55pm - 2:05pm HST
Nautilus 1

1:59pm HST

Growth Chambers and Controlled Environments 3 (CE 3)
Wednesday September 25, 2024 1:59pm - 3:45pm HST
Effects of Light Sources and Fertilizers on Biomass Production of Nine Lettuce Cultivars in a Hydroponic Nutrient Film Technique System - Dario Rueda Kunz
Enhancing Lettuce Yield: Strategies for Fertility Management in Soilless Growth Systems. - Bryce Waugh
Effect of ZnO and SiO2 Nanoparticles on Growth and Physiology of Hydroponic Lettuce Under Salinity Stress - Chungkeun Lee
An Intermediate Calcium-mobilizing Biostimulant Concentration Controls Tipburn of Two Greenhouse Hydroponic Lettuce Cultivars Without Affecting Growth -Shem Msabila
Optimizing Sampling Methods for Sap Extraction to Enhance Plant Nutrient Analysis in CEA - Husnain Rauf
Effects of Potassium and Iron Supplements and Late Nitrogen Restriction on Aquaponic Taro (Colocasia esculenta) Corm Production - Andrew Bohringer
Advantages of a novel in situ pH measurement for soilless media - Hikari Skabelund

Moderator
TR

Theodore Radovich

University of Hawai’i at Mānoa
Wednesday September 25, 2024 1:59pm - 3:45pm HST
Coral 1

1:59pm HST

Hemp Research and Extension 2 (HEMP 2)
Wednesday September 25, 2024 1:59pm - 3:45pm HST
In-vitro Screening of Native Plant Crude Extracts Against Major Plant Pathogens Affecting Cannabis and Specialty Food Crops of Louisiana - Jennifer Blanchard
Investigating Fiber Hemp Seed Size Impact on Germination, Emergence, and Early Growth Rate - Samantha Carroll
Modified Media and Lighting for Repeated In Vitro Cutting Cycles of Cannabis Sativa - Molly McKay
Differential effects of macro- and micronutrients on secondary metabolite production in drug-type (medical) cannabis - Nirit Bernstein
QTL mapping and gene discovery for seed traits in hemp (Cannabis sativa L.) F2 mapping populations - Luis Monserrate
Dynamics of Cannabinoid Accumulation and Morphological Changes in Cannabis Inflorescences - Samuel des Bordes
Variable Planting Date Influences on Growth and Development of Floral Hemp in North Dakota - Brock Schulz

Moderator
NB

Nirit Bernstein

Institute of Soil Water and Environmental Sciences, ARO, Volcani Research Center
NA
Wednesday September 25, 2024 1:59pm - 3:45pm HST
South Pacific 2

1:59pm HST

Propagation (PROP)
Wednesday September 25, 2024 1:59pm - 3:45pm HST
Enhancing Germination of Silver Saw Palmetto (Serenoa repens form glauca): Water Uptake, Temperature, and Pre Sowing Treatment Effects - Vania Pereira
Propagation Strategies and Epigenetic Variations in Vaccinium Berry Crops - Samir Debnath
The Application Timing of a Cytokinin B-Mo-based Product Affects the Growth and Non-Structural Carbohydrates Contents of Cuttings During Adventitious Root Development - Mayra Toro Herrera
Characterizing the effects of PPFD and VPD during indoor acclimation of Chrysanthemum cuttings - Ana Sofia Gomez
Asexual Propagation of Salix humilis Using Dormant Hardwood Cuttings After Stock Plant Coppicing and Fungicide Application - Hazel Schrader
Evaluation of Auxin Application and the Presence or Absence of Roots or Inflorescences in the Propagation of Variegated Carex wahuensis subsp. wahuensis - Paulo Matos
Evaluating the Effect of Plant Growth Hormone Types and Rates on Osmanthus spp. Propagation - Yulong Chen
Evaluating Leaf Cutting Success for Achimenes Propagation - Chad T. Miller

Moderator
PM

Paulo Matos

University of Hawai'i
Wednesday September 25, 2024 1:59pm - 3:45pm HST
Lehua Suite

2:00pm HST

CE 3 - Effects of Light Sources and Fertilizers on Biomass Production of Nine Lettuce Cultivars in a Hydroponic Nutrient Film Technique System
Wednesday September 25, 2024 2:00pm - 2:15pm HST
This study investigated the impact of two light sources and fertilizers on the growth of nine lettuce cultivars in a hydroponic nutrient film technique system. The research was prompted by reduced plant growth and acidity issues observed in the nutrient solutions in which Lettuce (Lactuca sativa cv. Salanova) was growing in previous experiments. The hypothesis posited that adjusting the ammonium/nitrate ratio in the nitrogen fertilizer source could mitigate acidity drops in the nutrient solution and consequently enhance biomass production. This experiment was conducted at Texas Tech University's Horticulture Gardens and Greenhouse Complex from October 10 to November 22, 2023. Treatments included combinations of two light sources (WhiteLEDs and LumiGrow TopLight Node™) and two fertilizer brands (Oasis and MaxiGro) containing different ratios of ammonium:nitrate; Oasis with 21.25:78.75, and MaxiGro with 15:85. Both fertilizers were maintained at the same concentration of nitrogen throughout the experiment, although the rates were changed according to developmental stage. The nutrient solutions initially contained 100 ppm N fertilizer for three weeks, followed by a water change and an increase to 150 ppm N.The pH and EC levels were closely monitored throughout the experiment. Results revealed significant differences among cultivars for all measured variables, with Salvius demonstrating superior performance in most aspects. The light source had no significant impact on aerial growth variables, while the MaxiGro fertilizer brand significantly and positively influenced plant weight, height, and root weight. Although there were significant interactions between light source, cultivar, and fertilizer for above-ground variables, these were highly dependent upon fertlizer. In conclusion, the choice of fertilizer brand is crucial for optimal lettuce growth in hydroponic systems. This study highlights the importance of selecting appropriate fertilizer characteristics to avoid detrimental effects on biomass production. Further trials are recommended to validate these findings and address concerns for home and commercial growers in hydroponic lettuce production.
Speakers
DR

Dario Rueda Kunz

Texas Tech University
Co-authors
CS

Catherine Simpson

Texas Tech University
NA
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Coral 1

2:00pm HST

HEMP 2 - Variable Planting Date Influences on Growth and Development of Floral Hemp in North Dakota
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Commercially produced floral hemp (Cannabis sativa L.) is high in cannabidiol (CBD) concentrations relative to tetrahydrocannabinol (THC); this is intentional due to regulatory pressures requiring low THC thresholds. Given the predominant role of genotype in plant development, it is crucial to also explore environmental factors that may allow for optimization of hemp growth, yield, and quality. The goal in this study is to evaluate the extent to which an extended vegetative growing period has on height, width, and yield in irrigated raised bed production of floral hemp in North Dakota. To survey this relationship between planting date, growth, and quality parameters, mother plants were germinated from seed at the beginning of the growing season. Each treatment group of cuttings, separated by approximately two weeks, were excised from their respective cultivar mother plant for four timing treatment groups. Cultivars evaluated were ‘ACDC’, ‘Bubbatonic’, ‘Sour Elektra’, and ‘Umpqua’. The main effect of cultivar did not significantly affect any measured parameters except for height and the top 1/3 portion of dry floral biomass. Planting date treatments significantly affected the wet weight of total above-ground biomass, total dry above-ground biomass, and total floral biomass. Average total above-ground biomass and dry floral biomass was statistically different for each planting date except for the last two planting dates (June 19 and July 3). Total above-ground dry biomass averaged over cultivars, were 4070 g, 2432 g, 1323 g, and 894 g, for dates May 19, June 5, June 19, and July 3, respectively. Mean yields for total dry floral biomass, averaged over cultivars, were 1779 g, 1279 g, 784 g, and 535 g, for dates May 19, June 5, June 19, and July 3, respectively. Earlier planting dates showed an increase in height for three of the four cultivars with the exception of ‘Umpqua’. A cultivar interaction with planting date treatment occurred for the top 1/3 portion of dry floral biomass and indicated that earlier planting date increased the biomass for ‘Bubbatonic’ and ‘Sour Elektra’ while planting date did not influence dry biomass for ‘ACDC’ and ‘Umpqua’. The insights gained from assessing the impact of variable vegetative growing periods on growth and quality parameters of photoperiod-dependent floral hemp could have broader implications for optimizing production practices. Understanding the intricate interplay between genotype, environmental factors, and cultivation practices is essential for advancing sustainable and efficient hemp cultivation strategies.
Speakers
BS

Brock Schulz

North Dakota State University
Co-authors
CA

Collin Auwarter

North Dakota State University
NA
HH

Harlene HattermanValenti

North Dakota State University
Wednesday September 25, 2024 2:00pm - 2:15pm HST
South Pacific 2

2:00pm HST

PROP - Enhancing Germination of Silver Saw Palmetto (Serenoa repens form glauca): Water Uptake, Temperature, and Pre Sowing Treatment Effects
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Silver saw palmetto is a native palm of the southeast coast of the United States that is of high ornamental value for native landscapes and commercial potential production due to its fruit’s phytotherapeutic properties. The main propagation method for this palm is seed-based germination, which has very slow and low germination rates. This study assessed imbibition rates, germination in different temperatures that simulated Florida seasons, and pre-sowing treatments. Diaspores were exposed to seeds within the endocarp, intact seeds, scarified seeds, and seeds with their operculum removed. The maximum fresh weight of saw palmetto seeds after imbibition was observed at 11 days. Significant differences in imbibition rates and final weight were noted for seeds with an endocarp, with lower fresh mass, and scarified seeds, which showed the highest rates. Summer temperatures consistently yielded the highest final germination percentage and uniformity for seeds with or without an endocarp on constant summer temperatures or move-along experiments throughout Florida seasons. Pre-sowing treatments, such as the removal of the operculum, proved to be highly efficient in promoting the highest germination percentages and rates, while seeds with an endocarp demonstrated lower and uneven germination. The application of hormones, particularly GA3 at 10,000 ppm, also showed promise in improving germination rates.
Speakers
VP

Vania Pereira

University of Florida
Co-authors
HP

Hector Perez

University of Florida
NA
JO

Jena Osmani

University of Florida
NA
TS

Thiago Souza Campos

UNESP - FCAV
NA
WV

Wagner Vendrame

University of Florida
NA
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Lehua Suite

2:00pm HST

VCM 3 - Evaluating The Effect Of Cultivar On Garlic Growth And Yield
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Assessing the impact of cultivar on garlic growth and yield ensures satisfactory productivity and better management of genetic resources for growers in North Dakota. A field experiment was conducted at the NDSU Horticulture Research Farm, located near Absaraka, ND to evaluate the effect of cultivar on the growth and yield of garlic. Twenty-nine garlic cultivars were arranged in a randomized complete block design (RCBD) with 4 replications. The leaf number, bulb diameter, bulb weight, scape weight and length were recorded throughout the growing season. The results showed significant differences between cultivars for all the variables evaluated. The highest bulb diameter(60.5 cm) was recorded in ‘German White’, while the lowest diameter (38.9 cm) was recorded in ‘German Red’. The highest bulb weight(73.4 g) was with ‘German White’ while ‘Italian Loiacono’ resulted in the lowest bulb weight(21.2 g).The number of leaves was recorded at 30, 45, 60, and 80 days after sprouting (DAS). The average number of leaves was similar for all cultivars until 60 DAS when ‘Ukrainian Red’ had the highest number of leaves (11) and ‘German Red’ had the fewest leaves (7). ‘Dakota White’ produced the longest scapes while ‘Italian Loiacono’ and ‘White Spring’ did not produce any scapes. ‘German White’ recorded the heaviest scapes (13.8 g). In conclusion garlic cultivar affected the growth and yield when grown under North Dakota environmental conditions. ‘German White’ appeared to be the most adapted to North Dakota environmental conditions while ‘Italian Loiacono’ and ‘German Red’ were the least adapted.
Speakers
SM

Stephen Mensah

Graduate Research Assistant, North Dakota State University
Greetings! I'm Stephen Mensah, proud son of Ghana. My journey began with a Bachelor's degree in Agriculture from the esteemed University of Cape Coast, Ghana. Now, I'm embarking on an exciting chapter as a graduate student at North Dakota State University, passionately pursuing a... Read More →
Co-authors
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Kahili

2:00pm HST

Fruit, Vegetable, and Edible Crops Collaboration Session
Wednesday September 25, 2024 2:00pm - 3:00pm HST
A forum for discussion of potential collaborations with regards to fruit, vegetable, and edible crops – i.e. citrus, breeding, production systems, postharvest, pomology, crop management, viticulture, etc.
Wednesday September 25, 2024 2:00pm - 3:00pm HST
Coral 4

2:00pm HST

Workshop: Evaluation Methods to Assess the Drought Tolerance of Landscape Plants in the Western United States
Wednesday September 25, 2024 2:00pm - 4:00pm HST
This workshop is to introduce the coordinated network of non-biased plant trials that has been successfully established to assess plant growth and aesthetic quality under deficit irrigation in six locations with different climate and soil types. The standard evaluation method will be highlighted to allow the audience to gain a behind-the-scenes look at the success and challenges of managing a multi-year and multi-state field project titled ‘Climate Ready Landscape Plants’. The evaluation methods employed in this project could potentially be utilized for selecting climate-resilient plants in other regions of the United States and beyond.

During their presentations, participants will be invited to: 1) Learn about the process of building cooperator and stakeholder engagement for a regional multistate project. 2) Practice using an Excel-based Irrigation Log to apply deficit irrigation using reference evapotranspiration published by local weather stations. 3) Practice evaluating selected landscape plants (pictures and/or live plants purchased from Home Depot in Honolulu) using the Rubric for Plant Aesthetic Ratings developed by the UC Landscape Plant Irrigation Trials™ team. 4) Learn the standard methods for collecting plant physiology data of selected landscape plants across multiple locations and understand the project results regarding stomatal conductance, which was collected using LI-600 Porometer/Fluorometer, LI-6800 Photosynthesis System, and/or CIRAS-3/4 Portable Photosynthesis System, METER Groups, etc. Ventors such as LI-COR Biosciences, PP Systems and/or METER Group will be invited to demonstrate their equipment for plant physiological measurements (e.g. stomatal conductance) during the session. 5) Learn the standard methods for collecting plant growth and visual quality data across six locations and understand the challenges and results of common taxa tested in six diverse geographic locations. 6) Learn step-by-step how to conduct open houses and invite professionals to help evaluate plants in the field trials, as well as how to collect and use the data.

Following their presentations, the six speakers along with other team members including Dr. Alessandro Ossola, Dr. Lloyd Nackley, Dr. Ryan Contreras, Dr. Shital Poudyal, and Dr. Youping Sun, will be invited to join a 30-min panel discussion session to further share the success and challenges of managing a multi-year and multi-state field project. They will delve into the opportunities and challenges currently facing the Green Industry. This discussion aims to foster future collaboration for expanding current research and Extension efforts. The goal is to promote the production and utilization of low-water-use plants within the green industry and among the gardening public, especially in the context of a changing climate.

Western U.S. nursery stock, bedding, annual, and perennial plant sales exceeded $2.9 billion in 2017, with nursery stock sales from this region alone accounting for 37.6% of total U.S. sales (Agricultural Statistics, 2017). However, climate change and increased urban water demand threaten the future of the Green Industry. The Western U.S. is expected to endure extreme droughts escalating in severity due to climate change, less predictable precipitation patterns, and decreased soil moisture (Cayan et al., 2010). Urban water supplies will be further stressed by population growth. The populations of Arizona, Idaho, Nevada, and Utah increased by 1.7% or more from 2017 to 2018 (United States Census Bureau, 2018). To address these challenges, growers must supply low-water-use plants and the landscape industry must utilize them to facilitate water conservation by reducing landscape irrigation requirements. In response to this need, the USDA Agricultural Marketing Service Specialty Crop Multi-State Program funded a project titled ‘Climate Ready Landscape Plants’ in 2020 to the University of California, Davis. With the funding, trial methods developed in California have been expanded to four additional western states: Arizona, Oregon, Utah, and Washington. A coordinated network of non-biased plant trials has been established to assess plant growth and aesthetic quality under three irrigation frequencies. Low-water-use plants were identified in 2022 and 2023 and will be recommended for production and utilization. The information developed will be provided to the green industry to aid in sustainable decision-making, marketing, and business support. The evaluation methods employed in this project could potentially be utilized for selecting climate-resilient plants in other regions of the United States and beyond. Agricultural Statistics 2017. 2017. United States Department of Agriculture National Agricultural Statistics Service. https://www.nass.usda.gov/Publications/Ag_Statistics/2017/Complete%20Ag%20Stats%202017.pdf Cayan, D.R., Das, T., Pierce, D.W., Barnett, T.P., Tyree, M., and Gershunov, A. 2010. Future dryness in the southwest US and the hydrology of the early 21st century drought. Proceedings of the Natl. Acad. of Sci. 107 (50), 21271-21276. https://doi.org/10.1073/pnas.0912391107 United States Census Bureau. 2018. Nevada and Idaho are the nation’s fastest growing states. United States Department of Commerce. https://www.census.gov/newsroom/press-releases/2018/estimates-national-state.html

Coordinator(s)
  • Youping Sun, Utah State University, Department of Plants, Soils & Climate, Logan, Utah, United States
Moderator(s)
  • Lloyd Nackley, Oregon State University, Horticulture, Aurora, OR, United States
Speaker/Participant(s)
  • Lorence Oki, Building Cooperator and Stakeholder Engagement for a Regional Multistate Project 
  • Jared Sisneroz, Coordinating a Standard Irrigation Protocol across Six Diverse Plant Trial Locations 
  • Karrie Reid, Introducing the Criteria for Plant Aesthetic Ratings
  • Natalie Levy, A Step-by-Step Guide for Organizing a Successful Open House Event
  • Soo-Hyung Kim, Coordinated Assessment of Physiological and Morphological Traits of Landscape Plants across Multiple Locations in the Western United States
  • Ursula Schuch, Performance of Landscape Shrubs under Three Irrigation Regimes in Arizona
Moderator
avatar for Lloyd Nackley

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
Speakers
KR

Karrie Reid

Env. Hort Advisor, ret'd., University of California
SK

Soo-Hyung Kim

Dr. Kim is a Professor and Plant Ecophysiologist whose research focuses on how plants interact with their environment at the whole-plant scale. He is the principal investigator for the ‘Climate Ready Landscape Plants’ project at the University of Washington.
NL

Natalie Levy

Dr. Levy is an Associate Specialist for Water Resources at the South Coast Research and Extension Center. She specializes in landscape plant water-use efficiency research, water resource management, and water pollution prevention/mitigation.
US

Ursula Schuch

University of Arizona
Dr. Schuch is a Professor and Extension Specialist in Environmental Horticulture in the School of Plant Sciences. Dr. Schuch’s research focuses on plant selection and management strategies to conserve water, maintain plant health, and aesthetic function. She is the principal investigator... Read More →
LO

Lorence Oki

University Of California, Davis
JS

Jared Sisneroz

UC Davis
Mr. Sisneroz is the project manager of the UC Landscape Plant Irrigation Trials (UCLPIT) and the ‘Climate Ready Landscape Plants’ programs. He specializes in landscape plant water-use efficiency research and water resource management.
Wednesday September 25, 2024 2:00pm - 4:00pm HST
Coral 2

2:05pm HST

EcoPhys/HPRB/PGR - Characteristics of the Secondary Walls of Xylem of the Tomatoes Cultivated Under Water Deficit
Wednesday September 25, 2024 2:05pm - 2:15pm HST
The morphological characteristics of the xylem elements influence water ascent in the plants. Few models determine the physical process of water movement in the vascular system of plants based on the hydraulic architecture. This study aims to determine the anatomical characteristics of the xylem and potential hydraulic conductivity at different positions along of tomatoes (Solanum lycopersicum; Solanaceae). The xylem vessels characteristics were examined in four internodes using three segments in each internode. The analogy between Ohm’s law and Hagen-Poiseuille was used to determine the hydraulic conductivities. A successive decrease in the mean vessel diameters from the bottom to the top stem was observed, with a significant difference between successive decrease in the mean vessel diameters from the bottom to the top stem was observed, with a significant between different percentages of height. The variation of the hydraulic conductivity along the useful length of tomato allowed a better application of the Hagen-Poiseuille equation.
Speakers
MM

Marcio Mesquita

Federal University of Goiás
Co-authors
HO

Henrique Oliveira

Goiano Federal Institute
Wednesday September 25, 2024 2:05pm - 2:15pm HST
South Pacific 3

2:14pm HST

Genetics and Germplasm 2 (GG 2)
Wednesday September 25, 2024 2:14pm - 3:45pm HST
Updates on Curation and Standardization of Phenotypic and Genotypic Data for Horticultural Databases - Jill Bushakra
Identification Of Branched-Chain Amino Acid Derived Volatile Loci In Tomato (Solanum Lycopersicum) Using GWAS And WGCNA - Austin hart
Genomic Characterization of Cultivated and Wild Fragaria Species to Inform Germplasm Conservation and Breeding Practices - Alexander Sandercock
From 'Agawam' to 'Zinfandel': Fruit Quality And Metabolite Diversity In The USDA Grapevine Repository - Victoria Meakem
Moving Beyond Montmorency: Exploring the Genetic Diversity of Tart Cherry - Benjamin Gutierrez
Population affects growth and plant architecture in wild-collected Hydrangea quercifolia - Lisa Alexander
Moderator
Wednesday September 25, 2024 2:14pm - 3:45pm HST
South Pacific 1

2:14pm HST

Organic Horticulture/ Bioenergy - ORGH/BioECP
Wednesday September 25, 2024 2:14pm - 4:10pm HST
Phenotypic landscape of the photosynthetic performance and seed productivity of spinach germplasm under organic conditions - Vijay Joshi
The Southern Cover Crop Variety Trial Program - Assessing Regional Adaptation of Cover Crop Varieties Across the Southern US (Year 2) - Virginia Sykes
Production of short, medium and long season specialty crops in high-residue, no-till farming systems - Arianna Bozzolo
Comparison of Plastic Mulch and Cover Crops - Roller Crimper Systems on Weed Pressure Soil Moisture and Yield in Organic Strawberry Production - Arianna Bozzolo
Impacts of Organic Soil Amendments on Hemp Production - Arnab Bhowmik
Biomass Source of Biochar and Genetic Background of Tomato Influence Plant Growth and Development and Fruit Quality - Rishikesh Ghogare
Nitrogen Utilization from Compost in Organic Strawberries - Mark Kindred
Interactions between photoselective plastics and insect pest dynamics in an organic brassica vegetable system -Dilip Nandwani
Anaerobic Soil Disinfestation: A Non-chemical Approach to Managing Weeds and Nematodes in Sweetpotato - Simardeep Singh
Potential Establishment of Entomopathogenic Fungi as an Endophyte in Citrus Trees Over Time - Joseph Paoli
Impact of Biosolid Compost - Madeleine Tenny
Moderator
Wednesday September 25, 2024 2:14pm - 4:10pm HST
South Pacific 4

2:15pm HST

EcoPhys/HPRB/PGR - Molecular Assessment of Heat Sensitivity in Broccoli Flowering
Wednesday September 25, 2024 2:15pm - 2:25pm HST
In the warm growing season on the East Coast, broccoli crown development is often disrupted because insufficient cold accumulation for flower bud initiation and enlargement. As part of an effort to breed for adaptation to higher growing temperatures, we investigated whether the sensitivity is due to expression of one or more of the central genes involved in flower initiation. Broccoli transitions from vegetative to reproductive phase normally, it is the transition from reproductive meristem to floral meristem and flower bud that is arrested or delayed in warm temperatures. We compared the heat response of a highly sensitive genotype, ‘Clara’ and the most resistant available genotype ‘P13xP19’ (P. Griffiths, Cornell). Plants that had just entered the reproductive phase were exposed to temperatures that were either permissive (16/12°C Day/Night) or restrictive (28/22°C Day/Night) for three days, then RNA was isolated from the meristem. The RNA was sequenced, transcripts were identified and relative abundance of each transcript was determined. Transcripts were available corresponding to the genes of interest. The model is that various developmental and environmental cues affect expression of the integrator gene SOC. The expression level of SOC then influences a gene that maintains meristem (TFL1) and one that promotes flower development (LFY). The interplay between those genes in time and space is believed to control how big the meristem will get and when the meristem will start to make flowers. When LFY expression dominates, it promotes expression of AP1 (and paralogs) inducing floral primordia. A gene responsible for the heat sensitivity would have differential expression in heat only in the sensitive genotype. That was the case for TFL1 and one copy of SOC1, but not for the other genes. Therefore, heat sensitivity is caused by genes associated with meristem transition, not with the classic flower-initiation genes.
Speakers
TB

Thomas Bjorkman

Professor, CALS Horticulture
Co-authors
Wednesday September 25, 2024 2:15pm - 2:25pm HST
South Pacific 3

2:15pm HST

ORGH/BioECP - Phenotypic landscape of the photosynthetic performance and seed productivity of spinach germplasm under organic conditio
Wednesday September 25, 2024 2:15pm - 2:25pm HST
Identifying suitable genetics for low-input organic spinach production and ensuring an adequate supply of organic seeds are critical challenges for organic spinach breeders. This study comprehensively assessed 300 spinach accessions sourced from the USDA National Germplasm Repository and commercial checks. The field trials were conducted at Uvalde, TX, during the 2022-23 and 2023-24 growing seasons, focusing on biomass and nitrogen use efficiency. During the 2023-24 field trial, natural variations in leaf photosynthetic performance, including carbon assimilation, stomatal conductance, photosynthetic electron transport rate (ETR), and PSII actual photochemical quantum yield (PhiPS2), were analyzed utilizing an LI-6800 gas analyzer. The seed productivity traits, such as yield per plant and 100-seed weight, were evaluated at the Organic Seed Alliance Washington field site. The processed data were employed for Genome-Wide Association Analysis (GWAS) to identify underlying genetics associated with organic productivity and photosynthetic traits. Over 88k Single Nucleotide Polymorphisms (SNPs) dispersed across six chromosomes were utilized in the GWAS after stringent filtering criteria. Significantly associated SNPs and candidate genes were delineated for the targeted photosynthetic traits and seed productivity, shedding light on potential genetic factors influencing these crucial traits in organic spinach breeding programs.
Speakers Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
AF

Alice Formiga

Oregon State University
NA
MC

Micaela Colley

Organic seed Alliance
NA
Wednesday September 25, 2024 2:15pm - 2:25pm HST
South Pacific 4

2:15pm HST

CE 3 - Enhancing Lettuce Yield: Strategies for Fertility Management in Soilless Growth Systems.
Wednesday September 25, 2024 2:15pm - 2:30pm HST
The focus on sustainability and effective resource management is expanding along with the upward trend in greenhouse production. Precise application of fertilizers is becoming more and more important in a variety of agricultural systems. The physical and chemical characteristics of soilless growth media differ from those of soil, which causes differences in their ability to retain nutrients. As such, accurate rates of fertilizer are crucial. This study looked at 14 different fertilizer blends with varying percentages of potassium (0-200ppm), phosphorus (0-100ppm), and nitrogen (0-200ppm). Pots were filled with Berger BM6 media and then ‘Buttercrunch’ lettuce seeds were planted. With each treatment fertilizer rate, the plants were hand-watered once a week to maintain a 10% leaching fraction. The number of leaves, dry shoot weight, fresh root weight, dried root weight, and SPAD readings were among the end measurements. The study found that a mix of high rates of nitrogen, phosphorous, potassium fertilizer treatments increased fresh shoot weight. This emphasizes the need for additional study to determine the best fertilizer rates for various specialty crops grown in soilless greenhouse environment.
Speakers
BW

Bryce Waugh

Grad Student, Oklahoma State University
Co-authors
BD

Bruce Dunn

Oklahoma State University
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Coral 1

2:15pm HST

GG 2 - Updates on Curation and Standardization of Phenotypic and Genotypic Data for Horticultural Databases
Wednesday September 25, 2024 2:15pm - 2:30pm HST
The Genome Database for Rosaceae (GDR, https://www.rosaceae.org/) and the Genome Database for Vaccinium (GDV, https://www.vaccinium.org/), are databases that support genomics, genetics and breeding in under-represented crops like small fruits. These fruit crops include Fragaria (strawberry), Rubus (red raspberry, black raspberry, and blackberry) in GDR, and Vaccinium (blueberry and cranberry) in GDV. Data include curated genome sequences, genetic maps, markers, QTL, genes, transcripts, germplasm, and publications, made accessible to browse, query and download through easy-to-use web interfaces and tools. One of the objectives of a 2022-funded SCRI- project ‘Advanced National Database Resources for Specialty Crop Research and Improvement’ is to collect, curate, and integrate all types of genomics, genetics, and breeding big data in easy-to-use and robust crop-specific databases. In this presentation, we summarize our progress towards curating and making available phenotype and genotype data for strawberry. We also present a strawberry Crop Ontology we have developed with input from crop researchers and breeders from North America and Europe. Public availability of phenotypic and genotypic data in GDR, GDV, and GRIN-GLOBAL will allow easy access to this data to use in genome-wide association studies. Crop Ontology will enable digital capture and trait data integration across locations and projects.
Speakers
avatar for Jill Bushakra
Co-authors
CH

Chun Huai Cheng

Washington State University
NA
DM

Doreen Main

Washington State University
JY

Jing Yu

Washington State University
NA
JH

Jodi Humann

Washington State University
KB

Katheryn Buble

Washington State University
NA
NB

Nahla Bassil

USDA-ARS
NA
PZ

Ping Zheng

Washington State University
NA
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
Wednesday September 25, 2024 2:15pm - 2:30pm HST
South Pacific 1

2:15pm HST

HEMP 2 - In-vitro Screening of Native Plant Crude Extracts Against Major Plant Pathogens Affecting Cannabis and Specialty Food Crops of Louisiana
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Louisiana’s hot and humid climate provides the perfect environmental conditions for the growth of fungal and bacterial plant pathogens. These fungal infections are an obstacle to the success of commercial production of Cannabis sativa in the state. Two of the most recent and significant fungal diseases are southern blight caused by Sclerotium rolfsii and stem canker caused by Botrytis cinerea. However, there is a lack of formal and professional knowledge regarding fungi that infect medicinal hemp plants, and practical and effective methods for managing the casual agents of these diseases. The objective of this study was to identify natural plant products from two native plants of Louisiana, that have been reported in the Native American ethnobotanical literature to have antifungal/antibacterial properties. An in-vitro bioassay experiment was conducted using the agar plug diffusion method testing the antifungal inhibition of crude ethanol extracts from the two species against each of the two pathogens Sclerotium rolfsii and Botrytis cinerea, on four plates each of Extract 1 Diospyros virginiana L. and Extract 2 Equisetum hymale L. of 1/4PDA spiked at a dose of 250ppm, 500ppm, 750ppm, and 1000ppm against a control plate of 1/4PDA for six days. Based on this initial crude extract bioassay there is a highly significant difference in the two crude extracts (p=0.000105) when tested against Botrytis cinerea. There is also a significant difference in concentration. The test against Sclerotium rolfsii did not find any significant inhibition from either of the plant extracts tested. From our findings we will continue the research study to test the antifungal potential of crude ethanol extract as well as Hexane, chloroform, ethyl acetate soluble fractions of Extract 1 Diospyros virginiana. The goal of the study is to integrate the antifungal compounds and their application for the development of best practices in Cannabis production.
Speakers
JB

Jennifer Blanchard

Louisiana State University
Jennifer Blanchard is a botanist and Instructor of Horticulture in the School of Plant Environmental and Soil Sciences (SPESS) at LSU. She has created a new course at the university in Louisiana Medicinal Plants that focuses on the native indigenous plants of the state. She is also... Read More →
Wednesday September 25, 2024 2:15pm - 2:30pm HST
South Pacific 2

2:15pm HST

PROP - Propagation Strategies and Epigenetic Variations in Vaccinium Berry Crops
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Blueberry (Vaccinium sect. Cyanococcus Rydb.), lingonberry (V. vitis-idaea L.) and huckleberry (V. membranaceum; also called black huckleberry or black blueberry) are three important Vaccinium small fruit crops native to the North. They are valuable resources for bioactive components that play important roles in anti-oxidant, anti-tumor, anti-ulcer, and anti-inflammatory activities. They can be propagated to produce true-to-type plants either conventionally or by micropropagation. Propagation in vitro is now well accepted worldwide for commercial production of Vaccinium crops. Proficient plant propagation technique using shoot organogenesis and somatic embryogenesis was successfully established in blueberry and lingonberry. Shoot regeneration and proliferation in in-vitro conditions using various liquid bioreactors have successfully been achieved in various Vaccinium species. One of the major concerns in commercial production is the occurrence of variation in micropropagated plants. This presentation describes the in-depth progress of genetic and epigenetic variations in different Vaccinium species during micropropagation. It addresses different molecular techniques used to monitor true-to-type and epigenetics along with application of epigenetic variation in micropropagated Vaccinium berry crops. Keywords: blueberry, bioreactor micropropagation, DNA-methylation, huckleberry, molecular markers, lingonberry, somaclonal variation
Speakers
SD

Samir Debnath

St. John’s Research and Development Centre
Samir Debnath, Ph.D., P.Ag. Dr. Samir C. Debnath, a Research Scientist of Agriculture and Agri-Food Canada and an Adjunct Professor of Biology, Memorial University of Newfoundland, has authored and co-authored around 140 publications in peer-reviewed journals including review papers... Read More →
Co-authors
MS

Mehdi Sharifi

Summerland Research and Development Centre, AAFC, 4200 Highway 97, Summerland, British Columbia, Canada
Dr. Mehdi Sharifi is a “soil nutrient management” research scientist at Summerland Research and Development Centre in British Columbia, Canada. Before his current position, he was a professors at Trent and Dalhousie Universities. He completed two postdoctoral fellow positions... Read More →
RB

Rajesh Barua

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
SK

Sayani Kundu

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
SM

Sweety Majumder

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
US

Umanath Sharma

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Lehua Suite

2:15pm HST

VCM 3 - Optimizing Butterhead Lettuce Production in a High Tunnel Environment
Wednesday September 25, 2024 2:15pm - 2:30pm HST
The production of fast-growing vegetable crops (such as specialty type lettuces) in slightly modified environments using high tunnels are widely underutilized. These structures can be used in the Midwest for winter production of a wide variety of leafy greens, including specialty lettuce. These crops have potential to garner a market premium due to high demand when there are not many other local vegetables for sale. Therefore, a study was conducted in 2020 and 2021 to evaluate four butterhead lettuce varieties (‘Nancy’, ‘Rhapsody’, ‘Red Cross’ and ‘Skyphos’) to determine optimal density for maximum revenue generation on a 3 ft wide raised bed. Three rows per bed and at 9 in. between plants worked best for ‘Nancy’, ‘Rhapsody’ and ‘Skyphos’, while for ‘Red Cross’ (a small more erect growing variety), 4 rows per bed at 12-inch spacing between plants maximized productivity. Head diameters were also highest for ‘Nancy’, ‘Rhapsody’ and ‘Skyphos’ using the 3 row, 12 inch between plant spacings. Overall gross revenues obtained per high tunnel, depending on plant density and variety, ranged from $3,600 to $6,000 (sold per piece at $4 each) or $1,753 to $7,279 (sold by weight at $6/ lb) for a typical 26’ (wide) x 48’ (long) high tunnel. Although most revenues increased when sold by weight, some increased by 50% (e.g., Rhapsody when grown at 3 row and 12 in spacings). Additionally, ‘Nancy’ (green-leaf type) and ‘Skyphos’ (red-leaf type) tended to be of higher quality than the other varieties evaluated and would be the better varieties to grow in a lower Midwest high tunnel environment. Both ‘Nancy’ and ‘Skyphos’ had optimal gross revenues when grown at 3 rows per bed with 9 in-row spacings when sold by piece ($4,500) or weight ($6,979 and $6,426, respectively). Thus, it is important for growers to understand the importance of butterhead variety selection and plant density in a high tunnel, as well as the method sold to maximizes revenues.
Speakers
AW

Alan Walters

Southern Illinois University
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Kahili

2:25pm HST

EcoPhys/HPRB/PGR - Morpho-physiological Response of Plectranthus amboinicus under Flooding and Drought Stress
Wednesday September 25, 2024 2:25pm - 2:35pm HST
Water stress is one of the major limiting factors of crop growth and productivity worldwide. Plectranthus amboinicus (Jamaican Thyme) is an aromatic, spicy and medicinal plant which is also valued in the pharmacological industry. Although the plant is generally known to tolerate some levels of drought, its response to sequences of different water stresses is unknown. In this study, we investigated the effect of flooding and drought on the growth and development of Plectranthus amboinicus. The treatments were regular watering (RW), flooding (FL), drought (DR), and rehydration (RH) after drought. The result showed that plant height was significantly (p < 0.001) reduced in DR and FL plants while fresh aboveground weight was increased by ca. 17.4% in FL compared to RW. Stomatal conductance and transpiration rates were higher in FL plants but reduced drastically in DR. Moreover, chlorophyll fluorometric indices including maximum quantum yield efficiency of Photosystem II (Fv/Fm) and potential photosynthesis capacity (Fv/Fo) were significantly (p < 0.001) increased in the FL but decreased in DR plants. Leaf relative water content was significantly (p < 0.01) highest in the RH followed by the RW, and the least in DR and DH. Leaf cell electrolyte leakage was significantly (p < 0.05) higher in the RH followed by the RW while FL recorded the least cell electrolyte leakage. These results indicate that Jamaican thyme regulates physiological characteristics to tolerate flooding and demonstrate that DR poses a severe threat to plant development.
Speakers
SA

Samuel Asiedu

Dalhousie University
Co-authors
LA

Lord Abbey

Dalhousie University, Faculty of Agriculture
NA
RO

Rapahe Ofoe

Dalhousie University, Faculty of Agriculture
NA
SC

Sparsha Chada

Dalhousie University, Faculty of Agriculture
NA
ZW

Zijing Wang

Dalhousie University, Faculty of Agriculture
NA
Wednesday September 25, 2024 2:25pm - 2:35pm HST
South Pacific 3

2:25pm HST

ORGH/BioECP - The Southern Cover Crop Variety Trial Program - Assessing Regional Adaptation of Cover Crop Varieties Across the Souther
Wednesday September 25, 2024 2:25pm - 2:35pm HST
Cover crops provide numerous ecological benefits to production systems. Maximizing these benefits requires identifying species and varieties that are the best fit both geographically and for the planting/termination time frame dictated by the accompanying cash crop system. In 2019, the University of Tennessee began a cover crop variety trial to help growers make better informed decisions on which of a broad range of cover crop species and varieties worked best in their specific region and production system. In fall 2022, in collaboration with the Southern Cover Crops Council, this trial was expanded to cover a 10-state region of the Southern US (TN, FL, NC, KY, VA, SC, TX, GA, AR, and AL) and became known as the Southern Cover Crop Variety Trial. This trial program is currently in its second year, with each trial year running from fall through the following spring. Trial sites were planted in mid-October each year. Cover crop cover, weed suppression, height, biomass, and estimated nitrogen release were measured in early and late spring. Twenty entries each were evaluated in the 22-23 and 23-24 trial years. However, as a fee-based program, entries were submitted by public and private institutions and varied from year to year. Eleven of the twenty entries were evaluated in both trial years. In year one, top-performers by rank were largely uniform across sites, consisting primarily of cereal rye and hairy vetch varieties. Many clover species, particularly crimson clover, exhibited greater variation in performance ranking among locations. Performance values varied significantly among and within locations, species, and evaluation period. Data collection for year two will be completed in Spring 2023 and will be presented.
Speakers
VS

Virginia Sykes

University of Tennessee
Co-authors
AT

Alyssa Thelin

University of Tennessee
NA
AW

Alyssa Woodard

North Carolina State University
NA
AM

Amanda Mcwhirt

University of Arkansas
AG

Audrey Gamble

Auburn University
NA
CC

Carlene Chase

University of Florida
NA
CR

Chris Reberg Horton

North Carolina State University
NA
DB

Daniel Boakye

University of Florida
NA
DT

Danielle Treadwell

University of Florida
NA
DM

David McIntosh

University of Tennessee
NA
EH

Erin Haramoto

University of Kentucky
NA
EH

Esleyther Henriquez Inoa

North Carolina State University
FP

Francisco Palacios

University of Tennessee
NA
GM

Gabriel Maltais Landry

University of Florida
NA
LS

Lakesh Sharma

University of Florida
Dr. Lakesh Sharma is an assistant professor of soil fertility and sustainable agriculture at the University of Florida in Gainesville, FL. Lakesh has been farming since he was a child on his own farm. His academic school journey started in 2000. He is currently working on nutrient... Read More →
LW

Lexie Worley

University of Tennessee
NA
MR

Mark Reiter

Virginia Tech
NA
NB

Nick Basinger

University of Georgia
NA
NR

Nithya Rajan

Texas A
NA
RS

Ricardo St Aime

Clemson University
NA
RH

Rick Hitchcock

University of Georgia
NA
SB

S Brooke Keadle

University of Tennessee
NA
SN

Sruthi Narayanan

Clemson University
NA
Wednesday September 25, 2024 2:25pm - 2:35pm HST
South Pacific 4

2:29pm HST

Pomology 2/Horticultural Plant Reproductive Biology/Intellectual Property Rights (POM 2/HPRB/IPR)
Wednesday September 25, 2024 2:29pm - 4:30pm HST
Do Plant “Growth Regulators” Really Regulate Growth? Plant Development And Plant Growth Are Not Synonymous. - Ted DeJong
Using GDR to Enable Rosaceae Research - New Data, Functionality and Future Direction - Dorrie Main
Deployment of Multi-location Genomic Prediction Models for Fruit Crops Using GDR-BIMS - Craig Hardner
Raspberry Cultivar Evaluation Trial in Mississippi - Apphia Santy
Performance of AU Gold-fleshed Kiwifruit in Alabama - James Spiers
Evaluating Sufficiency Levels and Peach Leaf Analysis for Fertilizer Decision-Making - Juan Carlos Melgar
Moderator
DK

David Karp

University of California, Riverside
Wednesday September 25, 2024 2:29pm - 4:30pm HST
Nautilus 1

2:30pm HST

CE 3 - Effect of ZnO and SiO2 Nanoparticles on Growth and Physiology of Hydroponic Lettuce Under Salinity Stress
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Nanoparticles have unique physical and chemical properties, which can positively and negatively impact crop growth and tolerance to abiotic stresses. This study evaluated the potential of ZnO and SiO2 nanoparticles in alleviating salinity stress in hydroponically cultivated lettuce. Two-week-old lettuce seedlings (Lactuca sativa cv. Green Forest) were transplanted into a 5-L deep water culture system and grown for four weeks in a customized growth chamber set at 25°C with 230 µmol/m2/s PPFD. The nutrient solution was maintained at an electrical conductivity (EC) of 1.5 dS/m and pH 5.8, and replenished weekly. A factorial design was employed with four salinity stresses (non-saline, 50 mM NaCl, 33.3 mM CaCl2, 25 mM NaCl 16.6 mM CaCl2) and three nanoparticle treatments (no nanoparticle, 100 ppm ZnO, 100 ppm SiO2). Under non-saline conditions, both ZnO and SiO2 treatments showed no significant differences in shoot growth compared to the control plants. However, ZnO application reduced shoot biomass, leaf area, SPAD, chlorophyll fluorescence and net photosynthetic rate under CaCl2 and NaCl CaCl2 stress. SiO2-treated plants had higher SPAD than the control plants under CaCl2 stress but presented lower values under NaCl CaCl2 stress. Root growth also showed contrasting results based on the stress conditions. SiO2 application resulted in increased root dry weight, total root length and surface area under non-saline and CaCl2 stress, while they decreased under NaCl stress. Similarly, ZnO application enhanced root growth under non-saline conditions, but demonstrated negative effects under all salinity stress conditions. In conclusion, SiO2 nanoparticle application did not improve salinity tolerance in lettuce, except for root growth under CaCl2 stress, and ZnO nanoparticle treatments showed phytotoxicity in both shoots and roots under all salinity stress conditions.
Speakers
CL

Chungkeun Lee

Texas A&M University
Co-authors
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Coral 1

2:30pm HST

GG 2 - Identification Of Branched-Chain Amino Acid Derived Volatile Loci In Tomato (Solanum Lycopersicum) Using GWAS And WGCNA
Wednesday September 25, 2024 2:30pm - 2:45pm HST
A major focus in plant breeding has been the improvement of crops through various traits that affect disease resistance and yield. However, the focus on productivity has led to an inattentiveness to other traits that specifically affect produce quality. An example of a critical fruit quality trait is its flavor, contributing to our perception of aromatic volatiles. Even at nanomolar concentrations, aromatic volatiles can be perceived by the olfactory system and influence the liking of the fruit. The focus of this study was to investigate the genetic aspect of the branched-chain amino acid (BCAA) volatiles, derived from L-valine, L-isoleucine and L-leucine, in tomato fruits. It is generally considered that these BCAA-derived volatiles contribute positively to overall liking, because these are essential amino acids required by the human diet. To identify quantitative trait loci (QTLs) affecting the biosynthetic pathway for 11 BCAA-derived volatiles, a Genome-Wide Association Study (GWAS) was conducted using a diverse and unique panel of 167 tomato accessions. The GWAS was run using the FarmCPU model in GAPIT-R, with a total of 21,893,681 SNPs, 2,735,297 INDELs, and 154 structural variants across the genome. Furthermore, a weighted gene co-expression network analysis (WGCNA) was conducted in parallel to identify modules of co-expressed genes that cluster with known genes that affect the BCAA-derived volatile pathway. A total of 113 QTLs were identified from GWAS and 3024 co-expressed genes were identified from the WGCNA. Candidate genes were screened based on annotated biochemical function, overlap within the GWAS QTLs, and gene expression in the red-ripe fruits. This led to the identification of two candidate genes, one on the long arm of chromosome 1 and another on the long arm of chromosome 11. These genes are being knocked-out using CRISPR-Cas9, and current progress is aimed to confirm the validity and function of these genes in the near-future.
Speakers
AH

Austin Hart

University of Georgia
Co-authors
DT

Denise Tieman

University of Florida
EV

Esther van der Knaap

Institute of Plant Breeding, Genetics, and Genomics, University of Georgia
NA
MS

Manoj Sapkota

University of Georgia
NA
Wednesday September 25, 2024 2:30pm - 2:45pm HST
South Pacific 1

2:30pm HST

HEMP 2 - Investigating Fiber Hemp Seed Size Impact on Germination, Emergence, and Early Growth Rate
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Fiber hemp (Cannabis sativa L.
Speakers
SC

Samantha Carroll

Graduate Research Assistant, North Carolina State University
Co-authors
AC

Amanda Cardoso

North Carolina State University
NA
DS

David Suchoff

North Carolina State University
NA
RY

Rong Yin

North Carolina State University
NA
Wednesday September 25, 2024 2:30pm - 2:45pm HST
South Pacific 2

2:30pm HST

POM 2/HPRB/IPR - Do Plant “Growth Regulators” Really Regulate Growth? Plant Development And Plant Growth Are Not Synonymous.
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Much scientific literature refers to plant development and growth as though they are synonymous. While plant physiology texts (E.g., Taiz et al. 2015) and horticulture texts (E.g., Sansavini et al. 2019) emphasize the roles of various plant hormones in coordinating plant development, they simultaneously refer to them as plant growth regulators. On the other hand, the same texts emphasize assimilation processes and the important role of carbohydrate and nutrient availability as well as water relations in enabling growth to occur. The terms growth and development are often used interchangeably and the literature rarely emphasizes the difference between plant development and plant growth. This causes confusion and a lack of clear thinking when attempting to develop explanations for plant growth responses in specific circumstances. Hormone physiologists often try to explain particular growth responses in terms of hormonal theory whereas environmental physiologists will likely explain the same responses in terms of environmental conditions and availability for the resources required for achieving growth. In this paper I will argue for a clearer differentiation between plant development and plant growth and suggest that plant hormones should not be thought of as plant growth regulators, but rather as plant development coordinators. Plant development coordinators (plant hormones) set up the conditions necessary for plant growth but availability of plant growth substances; carbohydrate and nutrient availability along with temperature and water relations, are often what actually regulate plant growth rates. Treating development and growth as separate but interdependent processes could clarify much understanding of the underlying processes involved in the regulation of plant growth. These concepts will be discussed in the context of understanding the mechanisms involved in several physiological phenomenon of fruit trees.
Speakers
TD

Ted DeJong

UC Davis
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Nautilus 1

2:30pm HST

PROP - The Application Timing of a Cytokinin B-Mo-based Product Affects the Growth and Non-Structural Carbohydrates Contents of Cuttings During Adventitious Root Development
Wednesday September 25, 2024 2:30pm - 2:45pm HST
A large group of horticulture species are propagated vegetatively through shoot-tip cuttings harvested from stock plants and planted to form adventitious roots. Adventitious root development (ARD) leads to establishing a carbohydrate sink in the region of root regeneration, which is highly dependent on energy and carbon skeletons. We hypothesized that enhancing the source-to-sink relationship during ARD can lead to an efficient carbon allocation to growth, resulting in a well-rooted cutting. Thus, the research aimed to determine if the application time of a Cytokinin B-Mo-based product during the ARD of unrooted cuttings would impact the source-to-sink relationship and, hence, affect plug growth and quality. The product was applied at four application times plus a negative control as follows: T1: plants without product (control), T2: sticking stage (starting 24 h after the sticking); T3: callus formation stage; T4: root development stage; and T5: toning stage. The experiment was a complete randomized design with five treatments and 60 repetitions for treatment (n=60) in two experimental runs (n=120). The root and shoot length, the number of leaves, the leaf chlorophyll content, the root and shoot dry matter, and the root-to-shoot ratio were measured. Results indicate that applying the product at T2 in ARD's dedifferentiation and induction phase leads to the shortest root and shoot length, the lowest dry matter accumulation, and some phytotoxicity effects. For T3 in ARD's initiation phase, the application results in greater root, total dry matter, and total soluble sugar contents than the control. For T4 in ARD's expression phase, the application results in greater growth, total dry matter, and sucrose and starch contents than control and other treatments. Applying the product in T5 when the roots had grown and reached all the edges of the growing media did not have any benefit compared to the control. Our results suggest that the exogenous application of a product to strengthen the source-to-sink relationship during adventitious root development can potentially enhance the non-structural carbohydrate contents when applied at the root formation phase (T4), which correlates positively with the increase in the length and dry matter of the roots, generating a well-toned rooted cutting.
Speakers
avatar for Mayra Toro Herrera

Mayra Toro Herrera

Postdoctoral Research Associate, University of Connecticut
Co-authors
RR

Rosa Raudales

University of Connecticut
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Lehua Suite

2:30pm HST

VCM 3 - Resource Use Efficiency, Yield, and Quality of Amaranth Grown as a Summer Leafy Green in Alternative Soilless Systems
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Soilless growing systems (SGS) integrated into controlled environment agriculture (CEA) offer a viable solution for increasing food production in densely populated areas with limited land, water, and nutritional security. The design, components, inputs, and nutrient management of alternative SGS along with the plant genotype, directly impact crop yield, nutritional value, and resource use efficiency. As the adoption of CEA and SGS continues to expand, there is a growing need to compare and evaluate the performance of alternative SGS in terms of resource use efficiency, crop yield, and impact on crop nutritional quality. To this purpose, a study was undertaken to assess the performance of five alternative SGSs including Deep Water Culture (DWC), Nutrient Film Techniques (NFT), Ebb and Flow, Drip irrigation, and the Kratky system concerning yield, nutritional quality, and resource use efficiency, using green and red stripe amaranth cultivar as test crops. As expected, the Kratky system had the lowest dissolved oxygen levels in the nutrient solution compared to other SGSs. Among the growing systems, DWC and NFT exhibited higher fresh and dry biomass production compared to drip irrigation, ebb and flow, and the Kratky system. There was no distinct difference in leaf fresh and dry weight between cultivars, but green amaranth displayed higher stem fresh and dry weight than red stripe amaranth. Dry matter content remained unaffected by the SGS, while red stripe amaranth exhibited higher dry matter content compared to green amaranth. The Kratky and DWC systems utilized 34.2% and 25.6% less nutrient solution, respectively, compared to the ebb and flow system, which had the highest nutrient solution consumption compared to other methods. DWC had the highest water use efficiency (WUE, dry biomass produced per liter of water used). Nitrate content in amaranth leaves was higher when grown in NFT compared to drip irrigation, DWC, and ebb and flow, but was similar to Kratky. The red stripe cultivar displayed higher nitrate content than the green one. Regarding bioactive compounds, green amaranth exhibited higher total antioxidants and flavonoids, whereas DWC and NFT led to lower total phenols and flavonoids compared to the Kratky, ebb and flow, and drip irrigation systems. In conclusion, the DWC and NFT systems maximized yield, with DWC having higher water use efficiency, while Kratky, ebb and flow, and drip irrigation system resulted in higher nutritional quality of the amaranth grown as a summer leafy vegetable.
Speakers
PP

Pradip Poudel

The Penn State University
Pradip
Co-authors
FD

Francesco Di Gioia

The Pennsylvania State University
NA
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Kahili

2:35pm HST

EcoPhys/HPRB/PGR - Effects of Paclobutrazol, Progressive-raising Temperature and Spike-truncated Treatments on Phalaenopsis Join Grace ‘TH288-4’
Wednesday September 25, 2024 2:35pm - 2:45pm HST
Phalaenopsis is the most popular potted plant worldwide. However, its long spikes often lead to increased shipping costs and risks. This study investigates the effectiveness of varying the concentration, timing, and frequency of paclobutrazol (PP333) applications on shortening the spike of Phalaenopsis Join Grace ‘TH288-4’. Also we examine on different progressive-raising temperature promoting inflorescence development for prior anthesis, and on spike-truncated treatment optimizing flowering performance. Three experimental groups were established based on different PP333 application schedules: T2, T2T3 and T7T8 group. The PP333 concentrations used were 0, 250, 500, 750, and 1000 mg·L-1, applied as foliar sprays. The shortest spikes, measured from base to first flower, were observed in the T2 group with 750 and 1000 mg·L-1; the T2T3 group treated with 500, 750, and 1000 mg·L-1 PP333; and the T7T8 group treated with 1000 mg·L-1. These treatments resulted in spike lengths of 16.7-22.2 cm, which are 54-69% shorter than the control ones. PP333 application had minimal effects on other traits except root diameter. Subsequently, four experimental groups: G20, G25, G30, and G35 group, were set up based on different final flower induction temperature. Mature plants were applied with 750 mg·L-1 PP333 by foliar spray, after four weeks moved to a cool room as 20/18℃. Until the flower stalk bore 0-3 nodes, the G25, G30 and G35 groups were transferred to 25/20℃. While the flower stalk bore 4-5 nodes, the G30 and G35 group were moved to 30/25℃. When the flower stalk bore 6-7 nodes, the G35 group was finally cultured under 35/30℃. Half of plants were randomly selected and truncated the spikes while the first flower bud was 1-1.5cm long. The spike of the G35 and G30 were truncated on the 21st week, which took only 113 and 117 days from the day started placing at a cool room. The G25 and G20 group took 124 and 138 days respectively. The days to flowering of G35 and G30 group were less than G20 at least by 45 days. However, the flower of G35 group performed unusual and were the smallest. All flowers of spike-truncated plants were bigger than the controls under different temperatures. This study establishes a PP333 treatment and a flower induction temperature protocol, offering a strategy to effectively produce single-flowered phalaenopsis.
Speakers
YC

Yi Chien Lu

National Chaiyi University
Co-authors
ML

MingHua Lee

National Chiayi University
NA
RS

RongShow Shen

National Chiayi University
NA
Wednesday September 25, 2024 2:35pm - 2:45pm HST
South Pacific 3

2:35pm HST

ORGH/BioECP - Production of short, medium and long season specialty crops in high-residue, no-till farming systems
Wednesday September 25, 2024 2:35pm - 2:45pm HST
When speaking to diversified vegetable crop growers, one of the most often cited challenges is the management of weeds. This issue is even more prevalent for organic growers who lack any effective chemical weed control method and rely on crews to mechanically remove weeds from the fields. One possible alternative is the use of terminated cover crops as mulch on the soil surface to act as a physical barrier to prevent weed emergence. This cover crop mulch can be advantageous for a grower in addition to cover crops improving soil health and providing a habitat for beneficial insects. This experiment compared vegetable beds with cover crops terminated with a roller crimper to bare soil beds on short (squash), intermediate (pepper), and long (eggplant) growing vegetable crops and assessed crop performance. In both 2023 and 2024 a cover crop mix of rye and field peas was successfully terminated and provided ample biomass on the soil surface at the time of vegetable transplanting and throughout their grower and harvest. We found that cover cropped treatments led to improvements in soil fertility, higher numbers of soil-dwelling beneficial insects, and lower weed pressure that led to significantly higher yields. These results demonstrate a potential system for organic growers to integrate into their operation as a practice that can reduce time and labor costs for weed management along with improving the soil fertility and creating a system requiring fewer inputs.
Speakers
AB

Arianna Bozzolo

Rodale Institute
Co-authors
AS

Andrew Smith

Rodale Institute
NA
JP

Jacob Pecenka

Rodale Institute
NA
Wednesday September 25, 2024 2:35pm - 2:45pm HST
South Pacific 4

2:45pm HST

ORGH/BioECP - Comparison of Plastic Mulch and Cover Crops - Roller Crimper Systems on Weed Pressure Soil Moisture and Yield in Organic
Wednesday September 25, 2024 2:45pm - 2:55pm HST
While organic production of specialty crops has been highly successful in southern California, it relies heavily on the use of plastic mulch and intensive tillage for weed management. A two-year study conducted from 2022 to 2023 aimed to evaluate the impact of plastic mulch and a cover crop based reduced tillage system using a -roller crimper to terminate cover crops on weed pressure and yield in organic strawberry production. Bare root strawberry crowns of the Albion variety were transplanted into four treatments: 1) Sorghum-sudangrass (S. bicolor x S. sudanense) seeded at 100 kg/ha (Sorghum 1), 2) Sorghum-sudangrass seeded at 200 kg/ha (Sorghum 2), 3) buckwheat seeded at 67 kg/ha, or 4) plastic mulch as standard practice. Cover crops were broadcasted on 1.5 m wide raised beds in May and terminated with a roller crimper in August. Both seeding rates of Sorghum-sudangrass effectively suppressed weed growth before and after termination compared to buckwheat. The significantly lower biomass of buckwheat after termination, relative to the Sorghum-sudangrass treatments, indicates variations in weed suppression efficacy among cover crops. Total differences in soil moisture, calculated based on data collected weekly from after cover crop termination to end of harvest, indicate that all treatments resulted in lower soil moisture levels compared to the plastic control, with the buckwheat treatment showing the most significant decrease. At harvest there were no significant differences between plastic mulch and Sorghum-sudangrass 1 and 2 treatments, indicating comparable yields. Buckwheat resulted in the lowest yield, experiencing a 50% reduction compared to plastic mulch. Based on the findings, plastic mulch and Sorghum-sudangrass planted at different seeding rates can be considered effective alternatives for weed suppression and maintaining yields comparable to conventional plastic mulching. The choice between Sorghum-sudangrass seeding rates may depend on factors such as cost, availability, and specific field conditions. The reduced biomass production of buckwheat compared to Sorghum-sudangrass, coupled with its rapid decomposition rate, resulted in diminished efficacy of buckwheat in weed suppression. Consequently, reduced weed control was observed, leading to significantly lower yields in buckwheat-treated plots compared to Sorghum-sudangrass and control treatments. These findings suggest that buckwheat may not be a viable option for organic strawberry production under comparable conditions, emphasizing the importance of selecting cover crops with longer-lasting weed-suppressive qualities.
Speakers
AB

Arianna Bozzolo

Rodale Institute
Co-authors
AS

Andrew Smith

Rodale Insitute
NA
JP

Jacob Pecenka

Rodale Institute
NA
Wednesday September 25, 2024 2:45pm - 2:55pm HST
South Pacific 4

2:45pm HST

CE 3 - An Intermediate Calcium-mobilizing Biostimulant Concentration Controls Tipburn of Two Greenhouse Hydroponic Lettuce Cultivars Without Affecting Growth
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Lettuce (Lactuca sativa) tipburn is a physiological disorder that leads to unappealing browning or necrosis of young leaf tips and stems, caused by localized calcium deficiency. It negatively impacts crop quality and yield, making proactive management essential for achieving optimal production. The objective was to evaluate the efficacy of a calcium-mobilizing chemical biostimulant, applied in the nutrient solution, on lettuce growth and tipburn. We conducted a greenhouse experiment on two lettuce cultivars (‘Dragoon’ and ‘Rex’) using a randomized complete block design. The seedlings were grown indoors under continuous white light from light-emitting diodes (LEDs) with a mean daily light integral (DLI) of 26 mol⋅m−2⋅d−1. We transferred 11-day-old seedlings to deep-water-culture hydroponic trays in a greenhouse. The two cultivars were subjected to three replications and five biostimulant concentrations (BC) of 0 (control), 0.125, 0.25, 0.5, and 1 mL⋅L−1 of the nutrient solution. Plants were grown under an 18-h photoperiod with a mean DLI of 16.6 ± 2.0 mol⋅m−2⋅d−1 from both sunlight and supplemental white LEDs, an air temperature of 24.6 ± 3.1 °C, and relative humidity of 33.2% ± 9.5%. Plant data were collected 14, 21, 28, and 35 days after transplant (DAT). There was no visible tipburn 14 DAT; however, plant diameter and shoot mass (fresh and dry) decreased with increasing BCs. We observed tipburn 21 DAT in both cultivars. The control had the highest severity on a 0–5 scale (0 = no tipburn; 5 = severe tipburn) for ‘Dragoon’ (0.6) and ‘Rex’ (1.3), whereas no tipburn occurred under higher BCs (i.e., 0.5 and 1 mL⋅L−1). Tipburn progressed 28 DAT, when increasing the BC from 0 to 1 mL⋅L−1 decreased the tipburn rating from 3.3 to 0 for ‘Dragoon’ and from 4.1 to 0 for ‘Rex’. Plant growth was stunted under the highest BC (i.e., 1 mL⋅L−1). At 35 DAT, both cultivars had severe tipburn under the control but had decreasing tipburn severity as the BC increased. Plant growth was unaffected under the control and low BCs (i.e., 0, 0.125, 0.25 mL⋅L−1). Under the highest BC, ‘Dragoon’ had the longest roots, but ‘Rex’ had the shortest. In contrast, plants experienced phytotoxicity (reduced biomass and chlorophyll concentration) under the highest BC, i.e., (1 mL⋅L−1) though no tipburn was recorded. In conclusion, the optimal calcium-mobilizing BC was 0.5 mL⋅L−1, which minimized tipburn of greenhouse hydroponic lettuce without affecting biomass accumulation or causing phytotoxicity during later development stages.
Speakers
SM

Shem Msabila

University of Delaware
Co-authors
QM

Qingwu Meng

University of Delaware
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Coral 1

2:45pm HST

GG 2 - Genomic Characterization of Cultivated and Wild Fragaria Species to Inform Germplasm Conservation and Breeding Practices
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Understanding the genetic composition and diversity of plant collections is crucial for their effective management and utilization in breeding programs. Cultivated strawberry (Fragaria x ananassa) is a significant global crop, contributing substantially to the U.S. agricultural economy with more than $3 billion in production value. The USDA-ARS National Clonal Germplasm Repository (NCGR) maintains a collection of cultivated and wild Fragaria accessions, which provide a valuable source of disease-resistance and other quality traits for the improvement of cultivated strawberry. Despite the recognized importance of genetic diversity, an in-depth assessment of genetic relationships within the USDA-ARS collection remains incomplete. To address these gaps, we genotyped 1,876 cultivated and wild Fragaria accessions from NCGR using a strawberry 5K DArTag marker panel. The evaluation of microhaplotype-based missing data rates revealed an increase in percent of missing data with an increased distance from the cultivated strawberry. This trend is expected because the 5K panel was developed based on the octoploid cultivated strawberries. Among the species studied, the higher ploidy accessions representing F. x vescana, F. x ananassa, F. virginiana, F. cascadensis, and F. chiloensis exhibited the least missing data, with percentages of 2.6%, 5.0%, 7.5%, 10.2%, 14.7%, respectively. Conversely, diploid accessions mostly Asian F. daltoniana, F. nubicola, F. viridis (Eurasian), F. pentaphylla, and F. nilgerrensis displayed the highest percentages of missing data, with 87.1%, 82.5%, 80.2%, 80.2%, 79.9%, respectively. Utilizing the microhaplotypes derived from the 5K panel, a total of 17,925 SNPs were identified after quality filtering, which were then used to assess the ancestry and genomic diversity of the Fragaria species housed within the USDA-ARS collection. We performed PCA and UPGMA analyses, and found distinct species clusters for each putative taxonomic assignment, suggesting high concordance between sample genotype and species identity. Finally, species-specific loci were then identified and genomic diversity analyses were performed for species represented with more than five accessions. Our findings clarified the identity and diversity of Fragaria within the USDA-ARS germplasm collection, aiding in germplasm conservation efforts and informing future breeding initiatives.
Speakers
AS

Alexander Sandercock

Cornell University
Co-authors
CB

Craig Beil

Cornell University
NA
DZ

Dongyan Zhao

Cornell University
NA
MS

Manoj Sapkota

Cornell University
NA
ML

Meng Lin

Cornell University
NA
MH

Michael Hardigan

USDA-ARS Horticultural Crops Research Unit
NA
MS

Moira Sheehan

Cornell University
NA
NB

Nahla Bassil

USDA-ARS National Clonal Germplasm Repository
NA
RK

Ryan King

USDA-ARS National Clonal Germplasm Repository
NA
SC

Shufen Chen

Cornell University
NA
Wednesday September 25, 2024 2:45pm - 3:00pm HST
South Pacific 1

2:45pm HST

HEMP 2 - Modified Media and Lighting for Repeated In Vitro Cutting Cycles of Cannabis Sativa
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Micropropagation usually involves cytokinin in single-harvest batches. We report two in vitro studies with multiple harvest: (1) fed batch process with modified physical states and (2) LED light treatments. In (1), genotypes of Cannabis sativa were observed in stationary agar (A), stationary Oasis® infused with liquid (OIL) and agitated Oasis® infused with liquid (AOIL).Fifteen explants were planted in vessels with 120 mL DKW medium harvested on 3-week cycles, with 0 or 15 mL additional media. Harvested shoots, length, and dry mass from repeated cycles were recorded. Genotypes T1 and Peach failed on multiple harvest cycles and were eliminated, although single cycle had higher quality in OIL. BaOx and Cherry1 on OIL/AOIL with additions were better quality than A in five cycles. Shoots harvested increased from 15 to 30 in cycles 1-3 in OIL/AOIL, but in A were approximately 20, while length was longest in OIL/AOIL. By cycle 3, all measured responses were decreasing until cycle 5 where a minimum of 7 shoots per vessel or more were only in OIL, but shoots were too short to plant in greenhouse. In (2), blue and supplemental far-red were observed with in vitro shoots of BaoX and Cherry1. OIL treatments were placed in LED polychromatic and dichromatic light (white, high red:blue, medium red:blue, white w/5% far-red, high red:blue 5% far-red, medium red:blue w/5% far-red, low red:blue w/ 5% far-red) at similar intensities (190-240 µmols·m-2·s-116 h-photoperiod). Media additions were made with responses recorded bi-weekly. Five randomly selected microcuttings per vessel rooted ex vitro on mist bench for 16 days. Over multi-cycles, plants treated with 5% far-red increased number and length, while plants under higher blue light increased dry mass. Shoot number increased to 28 in cycles 1-3 with far-red, and 18 without before decreasing to initial 15 during cycle 5. The accumulated shoots per vessel over 5-cycles (10-weeks) was 108 with far-red, and 84 without. Shoot length in far-red-treated plants increased from 19 - 25 mm in cycle 3 before decreasing to 10 mm in cycle 5. Plants without far-red had 10 – 15 mm length the entire experiment. Dry mass was highest during cycle 1 with blue light before decreasing 50% in cycle 3, where it remained until cycle 5. Sixty-eight percent of shoots rooted regardless of prior in vitro treatment. OIL with media addition allowed shoots to be harvested five cycles, while signaling response of far-red light allowed increased productivity and length.
Speakers
MM

Molly McKay

Clemson University
Co-authors
EL

Elizabeth Luscher

Curio Wellness
NA
JF

James Faust

Clemson University
NA
JA

Jeffrey Adelberg

Clemson University
NA
MT

Matt Taylor

Curio Wellness
RK

Raghupathy Karthikeyan

Clemson University
NA
Wednesday September 25, 2024 2:45pm - 3:00pm HST
South Pacific 2

2:45pm HST

POM 2/HPRB/IPR - Using GDR to Enable Rosaceae Research - New Data, Functionality and Future Direction
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Initiated in 2003, the Genome Database for Rosaceae (GDR, www.rosaceae.org) is a comprehensive community database that provides access to curated and integrated genomics, genetics, and breeding data for the biologically and economically important Rosaceae family. It serves as steward of critical research and breeding data, and provides access to online query and analysis tools that enable researchers to readily interrogate this wealth of data, facilitating basic and applied research across Rosaceae. This presentation will highlight the impact of GDR on Rosaceae research, demonstrate new data and tools, and share plans for future development and sustainability options.
Speakers
avatar for Dorrie Main

Dorrie Main

Professor, Washington State University
I am a member of the Pullman Charter School Initiative team and am particularly interested in how to set up and maintain a thriving Washington State Charter School to serve the needs of Eastern Washington students.
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Nautilus 1

2:45pm HST

PROP - Characterizing the effects of PPFD and VPD during indoor acclimation of Chrysanthemum cuttings
Wednesday September 25, 2024 2:45pm - 3:00pm HST
During acclimation of unrooted cuttings (URC) under mist irrigation, the moisture status of URC is greatly affected by environmental conditions such as high photosynthetic photon flux density (PPFD) and vapor pressure deficit (VPD), both of which can cause rapid dehydration. The objective of this study was to characterize the effects of PPFD and VPD on indoor acclimation of Chrysanthemum ‘Olympia White’ URC. Cuttings were stuck in a peat-perlite substrate in propagation trays, placed under sole-source lighting in chambers where ultrasonic fog was used to automatically control relative humidity (RH). Mist irrigation was applied every 20 to 30 min for 3 h. Over 12 h, URC were exposed to 0, 35, 70, 80, 105, 140, or 210 µmol·m–2·s–1 PPFD and 70, 80, 90, or 100% RH setpoints, resulting in air VPD levels ranging from 0.02 to 0.59 kPa. In the chambers, there was a high level of environmental control, and PPFD did not affect air VPD (P = 0.712), which were therefore considered as independent climatic factors. Leaf temperature minus air temperature was considered an indicator of plant energy balance, where a warmer leaf than air temperature is a driver of evapotranspiration. Plant leaf temperature became cooler than the air temperature as air VPD increased (P = 0.024), likely caused by evaporative cooling of leaves. In contrast, increasing PPFD increased leaf temperature relative to air temperature, likely through radiant heating. Leaf VPD was positively correlated with air VPD (adjusted-R2 = 0.88) but was also affected by the interaction of PPFD and air VPD (P < 0.05). Two hours after misting was terminated (5 h total), some plants showed clear wilting especially under low RH. At 5 h, stomatal conductance and evapotranspiration of URC was increased by PPFD and decreased by air VPD (P < 0.01), although there was an interaction between PPFD and air VPD for stomatal conductance (P < 0.005). Further results highlighting responses to RWC, water uptake, and water loss will be presented.
Speakers
AS

Ana Sofia Gomez

Purdue University
Co-authors
CG

Celina Gomez

Purdue University
PF

Paul Fisher

University of Florida
NA
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Lehua Suite

2:45pm HST

VCM 3 - Improving Seed Germination, Seedling Biomass and Drought Tolerance of Microgreens Using Low-temperature Plasma
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Microgreens, harvested within 7-21 days, are nutritionally dense and are rich sources of antioxidants, minerals, and vitamins required for body and mental health. However, poor germination, leading to poor establishment, seed-borne diseases, and high water consumption often limit microgreen production. Low-temperature plasma (LTP) is a partially ionized gas with unbound electrons, neutral particles, ions, reactive nitrogen and oxygen species, and ultraviolet light. LTP is emerging as a viable non-chemical tool for seed priming, improving crop productivity, and disinfecting seeds and foods, among other uses. Thus, LTP may address the concerns limiting microgreen production. The effects of LTP on imbibition, germination rate of germination, seedling biomass, and drought tolerance were assessed primarily using mustard greens and ten microgreen crops with or without Ar or He Plasma at different exposure times. The drought tolerance experiment induced drought stress using PEG 6000 at 0 (Control), 5, 10, and 15% at w/v. The treated or untreated seeds were placed in Petri dishes and later transplanted into pots containing soilless potting mix. The days to first seed germination, germination rate, seedling height, root length, seedling and root biomass were recorded. Ar and He LTP hastened seed germination and increased the total seed germination percentage over Control. Ar and He LTP enhanced seed germination by 12.7% and 5.6%, respectively. He LTP increased seedling length by 40% and doubled the seedling fresh biomass over the Control. Ar LTP at 30 s and He at 90 s increased the root length by nearly 17% and 71% over that of Control, respectively. In another study, seeds directly exposed to either LTP or plasma-activated water (PAW) showed a 36% increase in seed germination compared to Control. Plant height significantly increased by 98% in Ar30 seconds and 50% (all other treatments) compared to Control. Exposure of seeds directly to He and Ar plasma also increased seedling biomass. He30s, He 60s, He 90s, and Ar 90s significantly enhanced biomass by 250%, 200%, 215%, and 120%, respectively compared to Control. In another study, seeds of ten microgreen crops exposed to Ar LTP for 30 seconds or He LTP for 90 seconds significantly boosted imbibition and germination rates compared to untreated seeds within 24 hours of treatment. The study showed that Ar or He LTP could improve the drought tolerance of microgreens by shortening the crop growing cycle and increasing root length without compromising seedling biomass.
Speakers
SM

S Mentreddy

Alabama A
Dr. Srinivasa Rao Mentreddy, an Indian-born American citizen, is a Professor of crop science at Alabama A
Co-authors
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Kahili

2:55pm HST

ORGH/BioECP - Impacts of Organic Soil Amendments on Hemp Production
Wednesday September 25, 2024 2:55pm - 3:05pm HST
Hemp (Cannabis sativa L.) is a highly versatile crop that has attracted considerable attention among farmers due to its diverse applications. Recent studies have sought to establish a fundamental understanding and baseline of the nutritional requirements of hemp, opening up possibilities for organic hemp production. Our research focuses specifically on evaluating the productivity of a floral hemp variety using different regenerative practices, with a particular emphasis on organic soil amendments that promote soil health in Piedmont area of North Carolina. The field experiment was conducted at North Carolina A
Speakers Co-authors
DR

Dipti Rai

North Carolina A
NA
KW

Kennedy Wimbish

North Carolina A
NA
Wednesday September 25, 2024 2:55pm - 3:05pm HST
South Pacific 4

3:00pm HST

CE 3 - Optimizing Sampling Methods for Sap Extraction to Enhance Plant Nutrient Analysis in CEA
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Plant sap analysis is a technique for monitoring plant nutrient status in real-time, enabling precise nutrient management to enhance growth and yield in controlled environment agriculture (CEA). Comprehensive sampling techniques are vital for accurate determination of nutrient concentrations, considering the variability of nutrients across different developmental phases of plants. However, questions remain regarding the selection of the appropriate plant tissues, including the number of leaves collected, sampling time, type and age of plant tissue, and frequency. Different crops need specific sampling procedures due to their unique leaf morphology, growth habits, and physiology. Many commercial laboratories only distinguish between new and old leaves. In this series of studies, we determined the most effective sampling method including the number of leaves, the type and age of tissue, as well as the timing and frequency of the collection. Optimal sampling techniques were identified for lettuce and tomato by conducting five different experiments across three cultivars. These experiments varied the number of leaves sampled (10, 20, 30 per sample with three replicates), types of tissue (leaves for lettuce with three replicates, and petioles and leaves for tomatoes with 20 each per sample), age of tissue (new vs. old with 20 leaves per sample and three replicates), time of collection (6, 8, 10 am with three replicates). For lettuce, two developmental stages (half and final harvest maturity), while for tomatoes, sampling frequency at four different growth stages was investigated (first fully expanded leaves, 1/3 and 2/3 of crop development, and final harvest). The results indicate that collecting 20 fully expanded leaves at 8 am, particularly at the final harvest, was considered the best sampling technique for nutrient analysis for both lettuce and tomatoes, providing the most effective sampling technique for optimizing nutrient management.
Speakers
HR

Husnain Rauf

University of Georgia
Co-authors
DJ

Daniel Jackson

University of Georgia
NA
JL

Jason Lessl

University of Georgia
NA
JS

Jessica Staha

Local bounti
NA
MP

Miguel Puebla

Pure flavor
NA
RS

Rhuanito S. Ferrarezi

University of Georgia
NA
TC

Timothy Coolong

University of Georgia
ZR

Zilfina Rubio

University of Georgia
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Coral 1

3:00pm HST

GG 2 - From 'Agawam' to 'Zinfandel': Fruit Quality And Metabolite Diversity In The USDA Grapevine Repository
Wednesday September 25, 2024 3:00pm - 3:15pm HST
The USDA National Plant Germplasm System is a network of germplasm repositories dedicated to conserving genetic diversity of crops and their wild relatives. The USDA grapevine (Vitis) repository contains 5000 unique accessions representing 36 species, and is divided between two locations: Davis, CA and Geneva, NY. While this material is available for distribution to researchers and breeders, there is currently limited characterization data to help requestors identify accessions with unique and valuable traits, particularly for fruit quality. Thus, we began a germplasm screening project to measure fruit quality traits of 481 unique accessions from both locations spanning three years (2022-2024). Fruit samples were juiced, filtered through cheesecloth, and analyzed for Brix, titratable acidity, and available nitrogen. Additionally, composition of phenolic compounds was assessed using liquid chromatography-mass spectrometry (LC-MS), and aromas were detected using solid phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Overall, there was a wide range of diversity in fruit quality traits across the collection. Brix values ranged from 8.5 to 30.1 (average=17.8), and titratable acidity ranged from 2.7 to 25.6 g mol-1 Tartaric acid equivalents (average=8.2). The phenolic compounds commonly detected in grape juice included the anthocyanins malvidin 3-O-glucoside and peonidin 3-O-glucoside, the hydroxycinnamic acid caftaric acid, and the flavonols quercetin 3-O-glucuronide and isoquercetin. Analysis of aromatic compounds revealed accessions that contained higher amounts of linalool, β-myrcene, and geraniol, which are associated with a “Muscat” flavor profile, while others contained methyl anthranilate, which is associated with a “Foxy” flavor profile. We hope this fruit quality dataset not only proves to be a valuable asset to researchers utilizing the USDA Vitis repository, but may also open new directions of exploration into improved grape flavor, nutrition, and quality.
Speakers Co-authors
Wednesday September 25, 2024 3:00pm - 3:15pm HST
South Pacific 1

3:00pm HST

HEMP 2 - Differential effects of macro- and micronutrients on secondary metabolite production in drug-type (medical) cannabis
Wednesday September 25, 2024 3:00pm - 3:15pm HST
The medical potential of cannabis (Cannabis sativa L.) is based on the complex chemical profile, comprising hundreds of secondary metabolites including cannabinoids, terpenoids and flavonoids. Cultivation conditions were demonstrated to affect plant development, function and production of secondary metabolites in cannabis. Understanding regulation of plant response to environmental conditions is key for development of optimal chemical profile for modern medicine. We have recently demonstrated sensitivity of the secondary metabolite profile in medical cannabis to mineral nutrition, with considerable responses to N, P, and K nutrition. Therefore, knowledge on the cannabis plant response to fertigation schemes is essential for the optimization of cultivation for production of high quality standardized material for the medical market, as well as for development of plant products containing specific desirable phytochemical profiles. In the talk, we will discuss our recent results concerning the potential of additional macronutrients and micronutrients to regulate plant development and the profile of active secondary metabolites in ‘drug-type’ medical cannabis. In pot experiments under controlled conditions, we demonstrated differential induction of changes in the cannabinoid and terpene profiles in ‘drug-type’ medical cannabis also by Ca, Mg, Zn and Mn. Furthermore, rate of uptake and deposition in the plants of individual macronutrients and micronutrients changes between the vegetative and the reproductive developmental stages, and along the reproductive phase.
Speakers
NB

Nirit Bernstein

Institute of Soil Water and Environmental Sciences, ARO, Volcani Research Center
NA
Wednesday September 25, 2024 3:00pm - 3:15pm HST
South Pacific 2

3:00pm HST

POM 2/HPRB/IPR - Deployment of Multi-location Genomic Prediction Models for Fruit Crops Using GDR-BIMS
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Multi-location genomic prediction models have been proposed as a strategy for aggregating disconnected phenotypic datasets to enable performance prediction of individuals into new environments. This approach also offers improved prediction accuracy and understanding of environmental stability. Multi-location GBLUP prediction models have been developed and used to study patterns in genotype-by-environment interaction for: flowering date in cherry across four locations in USA, France, and Italy; for sweetness in peach across four locations in USA; in strawberry across eight locations in USA, Australia, and Europe; and for fruit firmness in apple across five locations in USA and Europe. Here we present an online bioinformatics platform for the deployment of these models via the Breeding Information Management System (BIMS) in the Genome Database for Rosaceae (GDR). This platform enables performance of new material that has not been physically tested to be predicted for the traits across the environmental space included in the multi-environment GBLUP models. The predicted genetic value of each individual included in the GBLUP models for each trait in each environment was used with the GBLUP individual-by-marker allele frequency matrix to predict the genetic effect of each marker allele for each trait in each environment. A portal was then developed on BIMS to host this vector of marker effects and enable new users to upload tables of new individual-by-SNP marker data for the loci used in the original GBLUP model. Predictions for the new individuals are produced by multiplying the new sample-by-marker frequency matrix by the vector of predicted allelic effects. Predictions of the new material for each trait across environments are delivered alongside predicted performance of publicly available genetic material to enable comparison and evaluation of reliability of predictions. The use of this portal is demonstrated with genome-wide SNP genotypic data collected on new apple selections evaluated for an Australian genetic improvement program.
Speakers
CH

Craig Hardner

University Of Queensland
Assocaite Professor in quantitative genetic s and tree breeding of horticultural and forestry crops with particular foci on multi-variate mixed linear models, G-by-E, genomic prediction, multi-trait selection, modelling breeding strategies, conservation genetics, low-cost genotyping... Read More →
Co-authors
CP

Cameron Peace

Washington State University
DM

Dorrie Main

Washington State University
SG

Shashi Goonetilleke

University Of Queensland
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Nautilus 1

3:00pm HST

PROP - Asexual Propagation of Salix humilis Using Dormant Hardwood Cuttings After Stock Plant Coppicing and Fungicide Application
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Prairie willow (Salix humilis) is a naturally compact and adaptable shrub willow native to the eastern United States. This taxon has potential for use in managed landscapes because of its desirable habit, attractive flowers and foliage, and its purported tolerance to fluctuations in soil moisture. This adaptability could be advantageous for urban green infrastructure applications. However, unlike most willows, S. humilis is thought to exhibit recalcitrance to standard asexual propagation techniques. This recalcitrance is exacerbated by observed susceptibility to fungal infections that cause cutting mortality during propagation. Because juvenility can improve the rooting of propagules, we questioned whether stock plant rejuvenation (coppicing) and propagule treatment with fungicide would influence rooting and survival of S. humilis dormant hardwood cuttings. In February 2024, 300 full-length dormant stems were harvested at the USDA Plant Introduction Station in Ames, Iowa from stock plants that were either coppiced or not coppiced the previous year. Uniformly-sized basal cuttings were acquired by removing the proximal 23 cm of each stem. Experimental trials (N=300; n=75) evaluating the full factorial of stock plant status [non-coppiced (-coppice) or coppiced ( coppice)] and fungicide application [non-treated (-fungicide) or treated ( fungicide) by submerging propagules in T-Bird with 46.2% Thiophanate-methyl for 15 minutes] were conducted in a cool greenhouse at the University of Minnesota Horticultural Research Center in Chaska, MN. All cuttings were treated with 0.8% indole-3-butyric acid via Hormodin-3 Talc powder and stuck in 50 cell trays (5 × 5 × 12.5 cm cells) with a 1:1 perlite:bark-based media and placed on heat mats (22ºC) using a completely randomized design. Total number of propagules rooted, length of the longest three roots, and number of roots were recorded. Propagules were ranked on their overall rooting performance using a Likert Scale. Rooting percentage was 77%, 56%, 87%, and 69% for coppice/ fungicide, coppice/-fungicide, -coppice/ fungicide, and -coppice/-fungicide, respectively. Compared to the non-coppiced propagules, mean count of roots decreased by 41% for coppiced propagules, across fungicide applications. Compared to propagules not treated with fungicide, mean count of roots increased by 19% for propagules treated with fungicide, across coppice treatments. Future research will evaluate different types of cuttings to generate a complete vegetative propagation protocol for Salix humilis. This work supports the introduction of this versatile plant into commercial production, thereby augmenting the ornamental plant palette for challenging urban landscapes.
Speakers
HS

Hazel Schrader

Graduate Research Assistant, University of Minnesota Twin Cities
Co-authors
BM

Brandon Miller

University of Minnesota Twin Cities
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Lehua Suite

3:00pm HST

VCM 3 - Differential performance of Radicchio cultivars in New Hampshire
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Radicchio (Cichorium intybus var. latifolium) is grown widely throughout Europe, especially northern Italy. This crop features several groups that differ in color, shape, and culinary use, and there is considerable phenotypic variation among and within groups and cultivars. The New England growing climate is very different from that of major production regions in Europe and the pacific northwestern U.S. The availability of varieties to commercial growers in the U.S. has expanded greatly, but there remains a need for regionally relevant information about performance of these varieties. In Durham, NH, USA we grew 30 (2022) and 34 (2023) cultivars of radicchio belonging to seven main groups (Chioggia, Castelfranco, Treviso, Sugarloaf, Verona, Rosa del Veneto, and Lusia). In both years, they were seeded on 20-21 June, and transplanted on 14-15 July. Plants were harvested and weighed as they reached market maturity, or considered unmarketable due to bolting, rot, tipburn, or failure to head. We used standard cultural practices for the region: plants were grown in double rows on 30-inch-wide raised beds covered with white-on-black plastic mulch with drip irrigation. The weather in 2022 and 2023 differed greatly, with 2022 experiencing warm and dry conditions, and 2023 much wetter and cooler. The percentage of heads that became marketable ranged from 0-94% in 2022, and from 10-95% in 2023. Several cultivars had very high percentages of unmarketable heads, due to tipburn, rot, bolting, or failure to head. We also observed cultivar differences in susceptibility to powdery mildew. In both years, the cv. Rubro developed powdery mildew early and developed severe symptoms, several others eventually developed symptoms, and some never did. For traditional round red Chioggia types, several cultivars had very high percentages of marketable heads, and appear to be well adapted to production in the northeast. We identified cultivars within both sugarloaf and Treviso types that were well adapted, with high percentages of marketable heads. The cultivars we evaluated within the Lusia and Rosa del Veneto types were especially interesting from a culinary and attractiveness point of view, but had high percentages of rot (Lusia types) and very long days to maturity required (Rosa del Veneto types).
Speakers
BS

Becky Sideman

Member-At-Large
Co-authors
LH

Lilly Hartman

University of New Hampshire
MH

Mark Hutton

University of Maine
PG

Peyton Ginakes

University of Maine
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Kahili

3:05pm HST

ORGH/BioECP - Biomass Source of Biochar and Genetic Background of Tomato Influence Plant Growth and Development and Fruit Quality
Wednesday September 25, 2024 3:05pm - 3:15pm HST
The evolving effects of climate change and intensive agricultural practices have adversely affected soil health and crop yields. This necessitates the need to maintain and improve soil health for sustainable food production. Biochar, a carbon-rich material produced from pyrolysis of biomass is being considered as a novel soil amendment that can potentially restore soil health and improve crop yields. Several studies have reported both positive and negative effects of biochar on crop yields while focusing mainly on one type of biochar and a single plant cultivar. However, the effects of different types of biochar and its interaction with plants with different genetic backgrounds has remained unexplored. In this study, we evaluated the impact of six different biochars on the growth performance and fruit quality of three tomato (Solanum lycopersicum) cultivars. The hypotheses that (1) biochars derived from different feedstock sources would produce unique phenotypes in a single cultivar of tomato, and (2) single feedstock-derived biochar would produce different phenotypes in each of the three tomato cultivars were supported by obtained results. This study demonstrated that plant genetic background and biomass source are important variables to consider for using biochar as a soil amendment.
Speakers Co-authors
AD

Amit Dhingra

Texas A
NA
DI

Daylen Isaac

Washington State University
NA
ET

Elvir Tenic

Washington State University
NA
JL

June Labbancz

Texas A
NA
NR

Norman Richard Knowles

Washington State University
NA
Wednesday September 25, 2024 3:05pm - 3:15pm HST
South Pacific 4

3:15pm HST

ORGH/BioECP - Nitrogen Utilization from Compost in Organic Strawberries
Wednesday September 25, 2024 3:15pm - 3:25pm HST
Strawberries are typically grown in high tunnels in the Intermountain West region to protect the flowers and buds from early and late-season frosts and extend the growing season. Organic farmers rely on N mineralization from organic sources to supply plant-available N which can be inadequate for plant needs, especially when temperatures are low. To support cultivar selection for organic strawberry production in high tunnels, greenhouse cultivar trials were conducted to determine if some strawberries grow better on compost than others. Plants were grown for six weeks in a mixture of turface and peat moss with and without compost. A complete liquid fertilizer with and without added N was supplied daily. Leaf, crown, and root dry weights, tissue, and compost N at the beginning and end of each trial were measured and leachate was collected daily and analyzed for nitrate and ammonium. Plant chlorophyll was determined at the end of the experiment. Plants that received liquid N fertilizer grew more, absorbed more N, and had a higher chlorophyll reading compared to plants that received the compost and N-free fertilizer treatment. Ammonium was leached out of the compost-treated pots in the first two weeks while little nitrate was lost. Some cultivars performed better than others on the compost treatment. This suggests that some strawberry cultivars are better able to grow on organic nitrogen sources than others but, additional N fertilization may be needed.
Speakers
MK

Mark Kindred

Grad Student, Utah State University
I am a graduate student at Utah State University working on my master's degree in Dr Jennifer Reeve's lab. I got my bachelor's in plant science and Asian studies from Utah State University. While I was an undergrad, I worked in Jennifer Reeve's lab. When I graduated, I was offered... Read More →
Co-authors
BB

Brent Black

Utah State University
NA
JR

Jennifer Reeve

Utah State University
NA
RS

Robert Schaeffer

Utah State University
NA
Wednesday September 25, 2024 3:15pm - 3:25pm HST
South Pacific 4

3:15pm HST

CE 3 - Effects of Potassium and Iron Supplements and Late Nitrogen Restriction on Aquaponic Taro (Colocasia esculenta) Corm Production
Wednesday September 25, 2024 3:15pm - 3:30pm HST
The growing of taro in aquaponic systems has yielded corms significantly smaller than those grown terrestrially. Previous trials only partially supported the hypothesis that these low yields were due to excessive water and nitrogen levels late in vegetative development. A 2×2 (nitrogen restricted × supplemental fertilizer) factorial designed experiment was replicated 4 times in dual-tub systems. The 4 treatments tested were: 1) Fish effluent supplied throughout 10 months of plant development (T1); 2) Fish effluent restricted from the system at 6 months and fresh water supplied for the remaining 4 months of development (T2); 3) T1 plus supplemental potassium and iron fertilizer (T3); 4) Treatment 2 plus supplemental potassium and iron fertilizer (T4). The results indicate that the supplemental fertilizer was more important than effluent restriction late in development in enhancing corm growth, although effluent restriction did result in a higher maturity index of corms under supplemental fertilizer treatment. The corm yields were 140% higher in T3 (1.5 kg plant-1) than in T2 (0.63 kg plant-1). T4 had significantly more biomass partitioned into the corm (56% of total biomass) compared to T3 (44% of total biomass). The ratio of corm: total biomass is a key indicator of plant maturity and suggests restriction of high nitrogen effluent enhanced photosynthate translocation to the corm under supplemental fertilizer. Corm density was highest in T3 and lowest in T4, perhaps due to starch conversion to sugar in over-mature corms in T4. These results demonstrate the importance of supplementing potassium and iron fertilization, as well as restricting high nitrogen fish effluent late in taro corm development, to optimize taro yields and quality in aquaponic production systems.
Speakers
AB

Andrew Bohringer

University of Hawai'i at Manoa
Co-authors
BK

Bradley Kai Fox

University of Hawai'i at Manoa
NA
EC

Eric Collier

University of Hawai'i at Manoa
NA
KW

Koon-Hui Wang

University of Hawai'i at Manoa
NA
RP

Robert Paull

University of Hawai'i at Mānoa
NA
TR

Theodore Radovich

University of Hawai’i at Mānoa
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Coral 1

3:15pm HST

GG 2 - Moving Beyond Montmorency: Exploring the Genetic Diversity of Tart Cherry
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Genetic diversity is invaluable to the sustainability of American horticulture. In the case of tart cherry, production in the United States is precariously reliant on a single cultivar, ‘Montmorency.’ Our research explores diverse genetic resources in tart cherry to promote utilization of high quality and locally adapted cultivars for plant breeding and improved production. Tart cherry nutritional quality is of particular interest to consumers. The United States Department of Agriculture Tart Cherry collection in Geneva, New York maintains 100 cultivars of tart cherry, including their wild relatives. Over a five-year period, we assayed fruit quality traits, including Brix, titratable acidity, and phenolic content. Total soluble solids (TSS) ranged from 10.9 to 20.7% (average=14.8%) and acidity (TA) ranged from 5.3 to 32.1 g/L (average=16.3%). The sugar/acid ratio ranged from 3.7 to 27.6 (average=10.2). Individual fruit weight ranged from 0.2 to 8.6 g (average of 5.0 g) and pit weight percentage ranged from 6-32% (average=11%). Total anthocyanin content varied from 75.2 to 3760.0 μg/g, with an average of 771.4 μg. We also evaluated bloom phenology over a three-year period. The distribution of bloom ranged from 56.7 to 134.4 GDD, with an average value of 86.0 Growing Degree Days (GDD ). ‘Montmorency’ bloom was above average with values around 95.8 GDD. Sweet cherries (63.5 – 90.6 GDD) tended to bloom much earlier than tart cherries (64.9 –118.0 GDD) and P. fruticosa, the wild progenitor of the tart cherry, bloomed the latest with a range of 85.3 to 134.4 GDD. For Brix, acidity, and phenolic content, ‘Montmorency’ falls significantly below average, though it has a balanced sugar/acid ratio. ‘Montmorency’ is lacking in anthocyanin content which is increasingly relevant for the juice industry. It tends to bloom later than other tart cherries evaluated, though there are some more extreme late bloomers. This data will be available through GRIN-Global, the USDA germplasm database to facilitate future research and breeding.
Speakers Co-authors
Wednesday September 25, 2024 3:15pm - 3:30pm HST
South Pacific 1

3:15pm HST

HEMP 2 - QTL mapping and gene discovery for seed traits in hemp (Cannabis sativa L.) F2 mapping populations
Wednesday September 25, 2024 3:15pm - 3:30pm HST
The emergence of a thriving hemp industry in the U.S. will depend on the breeding of high-yielding regionally adapted cultivars. Despite the latest research efforts, little is known regarding the genetic basis of important agronomic traits in hemp. The objective of this research was to identify and characterize genomic regions associated with seed morphology and quality traits. F 2 mapping populations were developed by crossing hemp germplasm bred or cultivated for cannabinoids (‘FL 58’ × ‘TJ’s CBD’), grain (GVA- H-20-1179 × ‘Picolo’), or fiber (‘Si-1’ × GVA-H-21-1003) market classes. These populations were investigated due to their variation in seed size and seed crude protein. The cannabinoid, grain, and fiber populations were grown and seed was harvested in 2021, 2022, and 2023, respectively. Harvested seeds were phenotyped for thousand seed weight (TSW) and crude protein content predicted by near-infrared (NIR) spectroscopy. The high-cannabinoid population was genotyped using an Illumina array, while the fiber and grain populations were genotyped using an Agilent SureSelect Custom Target Enrichment Probe Set. Marker-associated sequences were aligned to the CBDRx v.2.0 reference genome to align the physical and genetic maps. The TSW and protein content in the cannabinoid population ranged from 9.62 to 23.93 g and 19.25 to 31.89 %, respectively. In contrast, the TSW of the fiber and grain populations ranged from 7.34 to 45.17 g and 8.73 to 31.42 g, respectively. Numerous quantitative trait loci (QTL) of varying effect sizes were identified genome-wide. Notably, in the high- cannabinoid population, major and minor effect QTL for TSW were detected on Chr01 corresponding to 642 kb and 5.56 Mb genetic regions, respectively. Our results in the cannabinoid population highlight the importance of developing more than one F 2 mapping population in a given cross to capture the effect of more alleles due to high heterozygosity in hemp and evaluating distinct pedigrees to sample additional alleles in diverse genetic backgrounds. Narrowing the region around or identifying candidate genes will allow the development of high-throughput molecular markers for beneficial alleles across mapping pedigrees. These findings will accelerate hemp breeding programs through the implementation of marker-assisted selection for high-yielding and high-quality hemp cultivars for grain production.
Speakers
LM

Luis Monserrate

Cornell University
Co-authors
AW

Alexander Wares

Cornell University
NA
DW

Dustin Wilkerson

Cornell University
NA
GS

George Stack

Cornell University
NA
JT

Jacob Toth

Cornell University
NA
LS

Larry Smart

Cornell University
NA
LV

Lucia Vignale

Cornell University
NA
MQ

Michael Quade

Cornell University
NA
Wednesday September 25, 2024 3:15pm - 3:30pm HST
South Pacific 2

3:15pm HST

POM 2/HPRB/IPR - Raspberry Cultivar Evaluation Trial in Mississippi
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Many states in the US produce raspberries, however, most of the production is concentrated in three states: California, Oregon and Washington as most raspberry cultivars grow best in regions with cool summers and mild winters. However, newer raspberry cultivars have been developed exhibiting heat tolerance. Cultivars with heat tolerance provide an opportunity for the growers in the Southern states to include raspberries in their crop production. Local Mississippi growers are interested in incorporating raspberries into their productions. However, there lacks research-based recommendations on raspberry cultivars suitable for Mississippi's climate. The objective of this study was to evaluate raspberry cultivars in terms of plant growth, heat and cold tolerance, pest and disease resistance, berry yield, quality, and fruiting season to identify the best-suited cultivars for Mississippi. This experiment was conducted in a randomized complete block design with two types of fertilizer: conventional and organic. Data collection included measurements of plant growth and performance, berry yield and quality and fruiting season. The results showed that raspberry yield, single berry weight and fruit size were influenced by fertilizer treatment. The soluble solid contents, acidity, and fruit color were not influenced by fertilizer treatment. Raspberry yield was higher for “Polka”, “Encore”, “Heritage”, and “Latham” under conventional fertilizer. Cultivars “Himbo”, “Prelude”, ‘Bp1”, and “Encore” treated with conventional fertilizer had higher single berry weight. The average fruit size of cultivars “Prelude”, “Himbo”, “Encore”, “Bp1” treated with conventional fertilizer produced larger fruits in comparison to the other cultivars. The fruit's soluble solid content was highest in “Heritage”, indicating a sweeter taste. Cultivars “Polana” and “Anne” produced fruits with the highest acidity, indicating a tarter taste compared to other cultivars. Fruit color varied between cultivars, with differences in lightness, redness, and yellow coloration.
Speakers
avatar for Apphia Santy

Apphia Santy

Graduate Student, Mississippi State University
Hello! I'm passionate about the world of horticulture and am eager to explore and discuss various opportunities within the industry. I am particularly interested in pursuing a PhD in horticulture, with a specialization in either specialty crops or ornamentals. Additionally, I have... Read More →
Co-authors
GB

Guihong Bi

Mississippi State University
NA
TL

Tongyin Li

Mississippi State University
NA
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Nautilus 1

3:15pm HST

PROP - Evaluation of Auxin Application and the Presence or Absence of Roots or Inflorescences in the Propagation of Variegated Carex wahuensis subsp. wahuensis
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Carex wahuensis subsp. wahuensis is an endemic Hawaiian species extensively used as a ground cover in landscaping and restoration. In recent years, a variegated form was identified and is now starting to be utilized in a handful of landscaping projects. While the green wild-type has been primarily propagated through seeds, protocols for single plant divisions are lacking and limits the commercialization and availability of the variegated form. In this study, we investigated the effect of indole-3-butyric acid (IBA) application as well as the presence or absence of roots and inflorescences on propagating single plant divisions of variegated C. wahuensis subsp. wahuensis. Container grown clumps were divided into single plantlets, with or without flowers and with or without roots (trimmed 7.6 to 10.2 cm length). For the first experiment, plantlets without flowers but with pre-existing roots were treated with or without 3000 ppm IBA and planted in 1:1 perlite and vermiculite. For the second experiment, plants with roots but with or without flowers, and plants without roots and flowers were also planted in 1:1 perlite and vermiculite. Both experiments were located on a mist bench, which activated every 2 minutes for 12 seconds, and both were allowed to root for up to 135 days. Root length and rooting index was recorded for the first experiment at 45 and 90 days after planting while rooting index was recorded for the second experiment at 45, 90 and 135 days after planting. Application of IBA did not improve root length and rooting index of plantlets. However, there was an observed difference in root length and rooting index between experimental runs. In the second experiment, plants with roots and no flowers exhibited the highest rooting index (3.3 = light rooting) followed by plants with no flowers and no roots (2.9 = alive but no roots to light rooting). Plants with flowers and roots exhibited the lowest rooting index (1.7 = mostly dead). Results of the study indicate that vegetative single plantlets of variegated Carex wahuensis subsp. wahuensis can be successfully rooted within 135 days after planting under mist.
Speakers
PM

Paulo Matos

University of Hawai'i
Co-authors
OB

Orville Baldos

University of Hawaii
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Lehua Suite

3:15pm HST

VCM 3 - Comparative Analysis of Biodegradable Mulch Use in Hill-side Strawberry Production
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Comparative analysis of biodegradable mulch use in hill-side strawberry production Plastic film (PF) is widely used in crop production, yet global environmental concerns urge for reduced plastic waste. Biodegradable and bio-based mulches emerge as promising alternatives, potentially crucial for sustainable agriculture. This significance is emphasized by the hypothesis that small farms prioritize sustainability and seek to reduce plastic waste in soil and food systems, especially if these alternatives match or exceed the benefits of plastic mulch. However, there is limited data available on the effectiveness of biodegradable paper (BP) and bio-based film (BB) in small-scale crop production, an area frequently affected by heat and drought stress. A field experiment was conducted on a strawberry field in Redlands, San Bernardino County, California during the seasons of 2022 and 2023, respectively. This study was conducted to identify the most appropriate alternative to plastic mulch in hill-side production systems under the Mediterranean climate as it relates to yield and fruit quality at harvest day. We used four common mulches in small farms in California, polyethylene mulch (PE), landscape paper mulch (PA), Coconut liner mulch (CL), Biodegradable plastic mulch (MB), and bare soil (control) with the most popular ever-bearing variety, ‘Albion’. To investigate the suitability and efficacy of his mulches, we recorded the soil properties (temperature, moisture, and pH) daily, fruit yield (fruit weight and fruits/plant) biweekly, and fruit quality (Soluble solid and color) at harvest considering farm stand or U-pick sale service. Our results indicate that the highest total yield in terms of total fruit weight and number of fruits per plant grows under MB, CL, and PF mulch respectively. No notable differences were observed among treatments in fruit quality parameters such as soluble solids and color. The soil under the coconut coir liner had the highest moisture content, compared to PE, BDM, and bare ground treatments. No significant difference was found among the treatments in weed control. By the end of the cropping period, all treatments adequately covered the soil surface. However, in the buried part of the mulches, the PA mulch exhibited considerable degradation before the end of the season, while the MB showed faster signs of biodegradation. Based on crop productivity and the different mulch efficacy observed in our study, this production system with CL and MB is a good alternative to compare to PE and PA mulches for ever-bearing hillside strawberry production in the Mediterranean climate.
Speakers
AM

Amrita Mukherjee

University of California Agriculture and Natural Resources (UCANR)
Co-authors
NP

Nolton Pattio

Jehovah Jireh Farm
NA
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Kahili

3:25pm HST

ORGH/BioECP - Interactions between photoselective plastics and insect pest dynamics in an organic brassica vegetable system
Wednesday September 25, 2024 3:25pm - 3:35pm HST
Brassica crops are susceptible to a variety of insect pests of particular significance in organic production systems, including flea beetles, aphids, and lepidopteran caterpillar pests. These pests are abundant on brassicaceous vegetable crops throughout the U.S. and populations frequently are high enough to significantly reduce crop quality. There is an increased interest among small and mid-size vegetable growers to adopt poly-covered tunnels to protect high value horticultural crops. Tunnel production allows for season extension, can protect crops from adverse weather conditions, improve the quality of horticultural crops, and may also influence plant-insect dynamics. Photoselective poly coverings influence light wavelength and transmission in tunnel environments and may affect plant physiological responses as well as incidence of disease and herbivory by insect pests. Here, we explored the impact of UV light blocking and UV light transmitting poly coverings on Lacinato kale (Brassica oleracea var. acephala) production and the effects on pest and beneficial insect populations in a tunnel environment compared to an open field system on certified organic land in Morris, MN. Our results showed that total kale harvestable yield was similar between the poly covered tunnels and open field plot treatments. No differences in yield or insect pest pressure were observed between UV light blocking or transmitting poly covered tunnels but were observed between tunnels and the open field environment. Imported cabbageworm populations were 75% higher in tunnels versus open field plots (P=.0023), however the inverse was observed for cabbage loopers, which were 60% higher in open field plots (P=.0072). No flea beetles were found in tunnels, and an average of 1 beetle/plant was observed in open field plots. Diamond back moth and aphid populations were not different between the tunnel and the open field plots. Overall, insect pest populations did not reach economically damaging thresholds during the study period, likely due to the field plot location which did not have a history of brassica production. Our results showed that light transmission and ambient air temperatures were similar under the photoselective poly coverings. We observed that pest pressure increases rapidly in tunnel environments as the season progressed regardless of poly covering. Although our study did not observe differences in the yield or quality of kale across production systems, there were differences in insect pest populations across systems, indicating a different management approach may be needed to prevent crop damage in tunnel environments.
Speakers
avatar for Dilip Nandwani

Dilip Nandwani

TN State University
NA
Co-authors
AF

Aimee Foster

University of Minnesota
NA
LW

Leah Worth

University of Minnesota
NA
MR

Mary Rogers

University of Minnesota
Wednesday September 25, 2024 3:25pm - 3:35pm HST
South Pacific 4

3:30pm HST

CE 3 - Advantages of a novel in situ pH measurement for soilless media
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Rhizosphere pH determines nutrient bioavailability, but this pH is difficult to measure. Standard pH tests require adding water to growth media. This dilutes hydrogen ion activity and increases pH. We used a novel, in situ, pointed-tip electrode to estimate rhizosphere pH without dilution. Measurements from this electrode matched a research-grade pH meter in hydroponic nutrient solutions. We then compared measurements from this electrode to saturated paste and pour-through methods in peat moss, coconut coir, and pine bark. The pointed-tip electrode was unable to accurately measure pH in the highly-porous pine bark media. Adding deionized water to the other media at container capacity using the saturated paste method resulted in a pH that was 0.59 ± 0.30 units higher than the initial in situ measurement at the top of the container. This increase aligns with established solution chemistry principles. Measurements of pH using the pour-through method were 0.38 ± 0.24 pH units higher than in situ measurements at the bottom of the container. We conclude that in situ pH measurements are not subject to dilution and are thus more representative of the rhizosphere pH than the saturated paste and pour-through techniques.
Speakers Co-authors
BB

Bruce Bugbee

Utah State University
NA
NL

Noah Langenfeld

Utah State University
NA
RH

Royal Heins

Utah State University
NA
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Coral 1

3:30pm HST

GG 2 - Population affects growth and plant architecture in wild-collected Hydrangea quercifolia
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Hydrangea quercifolia, oakleaf hydrangea, a flowering shrub native to woodlands of the southeastern United States. Oakleaf hydrangea has immense ornamental potential with four-season interest, including traits like showy panicles, striking foliage textures, red fall color, and exfoliating bark. Cultivars are often derived from wild selections either directly or only a few generations removed. Full genetic and phenotypic variation has not been evaluated for the species, and little is known about the diversity in horticulturally important traits for oakleaf hydrangea. For this study, growth and plant architecture of wild-collected oakleaf hydrangea seedlings were observed at the Otis L. Floyd Nursery Research Center in McMinnville Tennessee over a 3-year period. Seedlings from 14 populations of oakleaf hydrangea spanning the species’ native range were planted in a randomized complete block design containing six blocks and nine replications per block. Two-way ANOVA was used to partition variation in height, width, growth rate, and number of stems into sources attributable to block, population, and block × population. There were significant differences among populations for growth rate, size, and number of stems in all years. Southern populations were smaller than northern populations and showed a slower growth rate. Genetic and phenotypic variation shown among populations will guide conservation efforts and supplement breeding efforts for oakleaf hydrangea.
Speakers
avatar for Lisa Alexander

Lisa Alexander

Research Geneticist, USDA-ARS U.S. National Arboretum
Co-authors
AS

A. Sherwood

USDA-ARS, Agricultural Research Service, North Central Regional Plant Introduction Station
CJ

C. Jennings

Tennessee State University
SH

S.C. Hokanson

University of Minnesota
Wednesday September 25, 2024 3:30pm - 3:45pm HST
South Pacific 1

3:30pm HST

HEMP 2 - Dynamics of Cannabinoid Accumulation and Morphological Changes in Cannabis Inflorescences
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Cannabis (Cannabis sativa L.) is cultivated for its cannabinoids, which have applications for therapeutic and recreational use. This phenomic evaluation explores accumulation of 16 cannabinoids of interest and associated morphological changes in Cannabis flowers. Eight cultivars of interest were grown in containers within an environmentally controlled greenhouse for 150 days (72 days reproductive). Light intensity, light duration, temperature, and relative humidity were regulated. Monitoring floral development, we observed a consistent increase in cannabinoid concentration as flowers matured, peaking in advanced stages of development. This accumulation pattern was consistent across diverse cultivars, which indicates this accumulation pattern to be the result of a fundamental biological mechanism. Concurrent with cannabinoid accumulation, we noted morphological changes in trichomes, which are widely utilized as markers of maturation within industry. Trichomes transitioned from sparse and translucent to abundant, enlarged, and displaying orange/amber hues as flowers matured, signifying floral maturation and trichome senescence. Importantly, a significant linear correlation emerged between cannabinoid accumulation and trichome morphological changes across all cultivars. This underscores a tight relationship between cannabinoid biosynthesis and trichome development, shaped by genetic factors. In summary, our findings demonstrate the intricate relationship between cannabinoid accumulation and floral morphology in Cannabis. Insights gained are invaluable for cultivar selection, breeding, and cultivation practices aimed at optimizing cannabinoid quantity and time to harvest. Understanding the underlying molecular mechanisms of cannabinoids promises tailored approaches for the optimization of cannabinoid production and the fostering of therapeutic and industrial advancements in Cannabis.
Speakers
SD

Samuel Dotson

Louisiana State University
Co-authors
BJ

Babitha Jampala

Louisiana State University
NA
HK

Heather Kirk Ballard

SPESS
Heather Kirk-Ballard is an Assistant Professor and state extension specialist of Consumer Horticulture for the LSU AgCenter. She is the host of the Get It Growing ™ extension program focusing on home gardening that is disseminated weekly through video to news stations and in print... Read More →
Wednesday September 25, 2024 3:30pm - 3:45pm HST
South Pacific 2

3:30pm HST

POM 2/HPRB/IPR - Performance of AU Gold-fleshed Kiwifruit in Alabama
Wednesday September 25, 2024 3:30pm - 3:45pm HST
The performance of kiwifruit, primarily gold-fleshed cultivars, has been evaluated for many years in central Alabama, with the earliest plantings occurring at the Chilton Research and Extension Center, Clanton, AL in the mid-1990s. The objective of this study was to determine bloom times of female and potential male pollinizers, appropriate harvest times, and fruit quality attributes of ‘AU Golden Dragon’, ‘AU Gulf Coast Gold’, and ‘AU Golden Sunshine’. The female cultivar ‘AU Golden Dragon’ blooms earlier than other cultivars evaluated and had good bloom overlap with the male cultivar Hortkiwi ‘Meteor’. The female cultivars ‘AU Golden Sunshine’ and ‘AU Gulf Coast Gold’ bloom approximately 2 weeks after ‘AU Golden Dragon’ and had good bloom overlap with the male ‘AU Golden Tiger’. The harvest period in central AL for each cultivar based on flesh color (hue
Speakers
JS

James Spiers

Auburn University
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Nautilus 1

3:30pm HST

PROP - Evaluating the Effect of Plant Growth Hormone Types and Rates on Osmanthus spp. Propagation
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Osmanthus is a genus of ornamental plants with valuable qualities such as pest resistance, evergreen foliage, and aromatic flowers. However, different species respond differently to growth hormones for propagation. This study aimed to evaluate the types and rates of plant growth hormones on different species of Osmanthus propagation. Six distinct Osmanthus species (Osmanthus heterophyllus ‘Kaori Hime’, Osmanthus armatus ‘Jim Porter’, Osmanthus x fortunei ‘Patty's Secret’, Osmanthus heterophyllus ‘Rotundifolius’, Osmanthus delavayi, and Osmanthus x fortunei ‘Fruitlandii’) were treated with Indole-3-butyric acid (IBA) powder, 500 mg/L and 2000 mg/L of Potassium Indole-3-butyric acid (K-IBA), 10% Kelpak (seaweed extract), and water dip (the control). The cuttings’ survival rates, rooting rates, callus rate and area, and root length were recorded. The results showed the O. heterophyllus ‘Kaori Hime’ exhibited the best survival and rooting rates, while the O. heterophyllus ‘Rotundifolius’ had the lowest survival rate, the O. armatus ‘Jim Porter’ had the highest callus quantity. Plants treated with IBA powder had significantly larger callus area than those seaweed treatments. In conclusion, O. x fortunei 'Fruitlandii' and O. heterophyllus 'Kaori Hime' exhibit superior performance in all six measurements compared to other plant species and are highly recommended. Conversely, O. delavayi and O. heterophyllus 'Rotundifolius' have displayed considerably weaker performance and are not recommended. Further research is necessary to determine the effectiveness of other propagation methods and treatments for Osmanthus.
Speakers
avatar for Yulong Chen

Yulong Chen

The University of Georgia
Co-authors
LC

Lilin Chen

The University of Georgia
NA
PY

Ping Yu

University of Georgia
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Lehua Suite

3:35pm HST

ORGH/BioECP - Anaerobic Soil Disinfestation: A Non-chemical Approach to Managing Weeds and Nematodes in Sweetpotato
Wednesday September 25, 2024 3:35pm - 3:45pm HST
Anaerobic soil disinfestation (ASD) is a promising organic pest management strategy and is an alternative to chemical-led approaches that has shown potential to manage weeds and soil-borne pathogens in organic vegetable production systems. ASD is facilitated by incorporating carbon sources into the soil, tarping the soil with plastic mulch, and irrigating to the soil saturation point. To evaluate the impact of ASD on weed and nematode management in organic-grown sweetpotato, greenhouse studies were conducted at Clemson University, Clemson, South Carolina. Experiments were laid out in a randomized complete block design in 2-gallon microcosms with two carbon sources [ASD (soil amended with chicken manure molasses as carbon source) and non-ASD (non-amended control)] in the main plot and twenty sweetpotato genotypes in subplots. Three-week-old seedlings of tomato (cv. Rutgers) were planted in each microcosm followed by inoculation with 10,000 eggs of the southern root-knot nematode (Meloidogyne incognita). ASD was initiated one month post inoculation to allow nematodes to complete one life cycle. At the time of the ASD initiation, each microcosm was also inoculated with weed seeds [yellow nutsedge (10 tubers) and carpet weed (100 seeds)]. ASD was conducted for three weeks, followed by the transplantation of sweetpotato slips after one week of ASD termination. Weed counts, abundance of nematode second stage juveniles (J2) in soil, and sweetpotato above ground biomass data were collected. Our results suggested that the microcosms receiving the carbon amendment spent the most time under anaerobic conditions (
Speakers
SS

Simardeep Singh

Clemson University
Co-authors
CK

Churamani Khanal

Clemson University
NA
Wednesday September 25, 2024 3:35pm - 3:45pm HST
South Pacific 4

3:45pm HST

ORGH/BioECP - Potential Establishment of Entomopathogenic Fungi as an Endophyte in Citrus Trees Over Time
Wednesday September 25, 2024 3:45pm - 3:55pm HST
Entomopathogenic fungi offer an alternative strategy for citrus growers seeking environmentally friendly pest management solutions. This study aimed to assess the ability of a commercial strain of the fungus Beauveria bassiana to become endophytic in citrus plants after a single foliar application. A completely randomized block design, consisting of ‘Valencia’ sweet orange trees (Citrus × sinensis) grafted on ‘US-942’ (Citrus reticulata × Poncirus trifoliata) rootstock, was established under greenhouse conditions. Treatments comprised 6 replications of treated plants in two separate greenhouses (n = 16 per greenhouse), along with one control (water only). Treated plants were foliar sprayed asynchronously with the fungus at the beginning of each experimental trial per treatment. To assess endophytism over time, a series of cohorts were destructively sampled every two months. Spore deposition was assessed using cover slips post-spray application of all treatments. Additionally, detached leaves collected post-spray were imprinted on potato dextrose agar (PDA), amended with dodine and bactericides, to determine spore coverage of the leaf surface by counting colony forming units. To assess endophytism, sterile samples of plant organs (i.e., leaves, stems, and roots) were placed onto PDA-dodine plates to allow detection of phenotypic mycelia. Results from the first cohorts indicated successful application of the fungi on the citrus leaves, and endophytism was assessed after two months. Additionally, no statistically significant changes were recorded in terms of plant height, root, stem, and leaf biomass, as well as stem girth. This project contributed to a clearer understanding of the long-term endophytic persistence of commercially available entomopathogenic fungi and their effect on plant growth in citrus trees. The trial will continue in the field for additional screening.
Speakers
JP

Joseph Paoli

University Of Florida
I am a Master's student at the University of Florida based at the Indian River Research and Education Center (IRREC). I am a long-time Florida resident, having gone to Middle and High School in Central Florida before enrolling at the University of Florida. During my four years of... Read More →
Co-authors
ED

Edinson Diaz

University of Florida
NA
JF

John-Paul Fox

University of Florida
LC

Liliana Cano

University Of Florida
NA
LR

Lorenzo Rossi

University of Florida
MR

Mark Ritenour

University Of Florida
NA
PA

Pasco Avery

University of Florida
NA
TB

Terri Baker

Indian River State College and University of Florida
NA
Wednesday September 25, 2024 3:45pm - 3:55pm HST
South Pacific 4

3:45pm HST

POM 2/HPRB/IPR - Evaluating Sufficiency Levels and Peach Leaf Analysis for Fertilizer Decision-Making
Wednesday September 25, 2024 3:45pm - 4:00pm HST
The increasing demand for tree fruit production necessitates optimizing nutrient balance in intensified orchard systems to maximize profits efficiently. While peach growers are advised to follow Extension and recommended guidelines for fertilization, such recommendations may not align with orchard-specific variables and environmental conditions. As a consequence, crop sufficiency ranges may require updating to reflect modern growing practices and environmental factors. Although leaf nutrient analysis is the most reliable method for diagnosing tree nutritional status, the prevalence of annual fertilizer application, driven by the low cost of fertilizers relative to crop value, often leads to excessive fertilization in peach orchards. Consequently, our objective was to evaluate established sufficiency levels and leaf analysis as tools for determining the need for annual fertilizer applications. To achieve this, we implemented a two-year study involving two fertilization programs in an orchard with three rows of 17 peach trees: two rows adhered to grower standard, annual fertilization, while the remaining row followed a rational fertilization program. The latter implied applying fertilizer only when leaf analyses indicated nutrient concentrations below established sufficiency thresholds for peaches. Leaf analyses were conducted annually in July, and if nutrient concentrations were within or exceeded sufficiency thresholds, no fertilizer was applied postharvest or the following spring. If nutrient concentrations fell below sufficiency thresholds associated with a significant difference in yield and fruit quality between the two programs, fertilization occurred in late summer and during bloom time the following spring. We assessed tree quality and productivity by measuring yield (total weight of all the fruit per tree) and fruit quality (size and brix) annually. The results of the first year showed that despite deficient leaf nitrogen and phosphorus concentrations and other nutrients such as potassium, calcium, and magnesium remaining within or above their sufficiency ranges, we observed no significant differences in yield or fruit quality between trees subjected to rational and standard fertilization practices. Consequently, fertilization for the upcoming year was deemed unnecessary in trees following the rational program. The outcomes of this study are expected to guide peach growers in making informed decisions based on updated data, reducing the environmental impact of overfertilization, which is inefficient for fruit production and uneconomical, and enhancing farm profitability.
Speakers
avatar for Richardson Bien Aime

Richardson Bien Aime

Graduate student, Clemson University
- Plant and environmental sciences- Horticulture- Optimization of Peach Fertilization- Peach rootstocks- Agricultural economics- Sports- Music
Co-authors
JC

Juan Carlos Melgar

Clemson University
NA
Wednesday September 25, 2024 3:45pm - 4:00pm HST
Nautilus 1

3:45pm HST

Interest Group Session: Biotechnology of Woody Ornamental Plants, Interest Group Meeting, 2024 PB Awards
Wednesday September 25, 2024 3:45pm - 5:45pm HST
This year’s PB session will combine a keynote speaker session, business meeting and PB 2024 award ceremony together.
1. Keynote speaker: Hui Duan, USDA-ARS-REE (45 minutes) Biotechnology of Woody Ornamental Plants
2. PB business meeting (30 minutes) Chair annual report, elect new chair, chair elected and secretory. Plan next year’s work.
3. 2024 Plant Biotechnology Interest Group annual award ceremony (45 minutes)
Moderator
KD

Kedong Da

North Carolina State University
Director of plant transformation lab at North Carolina State University
Speakers
Wednesday September 25, 2024 3:45pm - 5:45pm HST
Kahili

3:55pm HST

ORGH/BioECP - Impact of Biosolid Compost on Lettuce Crop Growth and Physiology
Wednesday September 25, 2024 3:55pm - 4:05pm HST
Biosolids, derived from treated sewage sludge, represent a significant resource in sustainable agricultural production, with approximately 70 percent being utilized for land application in the United States. Recognized for their potential as organic fertilizers, biosolids undergo meticulous processing to meet grade AA standards before being blended with locally sourced organic materials, such as woody yard debris, in preparation for municipal distribution. This study delves into the effects of biosolids on soil and seed germination rates using various concentrations ranging from 1% to 7%. Findings reveal that higher concentrations of biosolids in soil significantly delay the germination of lettuce seeds. Through replicated mesocosm experiments at the Southwest Florida Research and Extension Center (SWFREC), UF/IFAS, Immokalee, we evaluate the effects of biosolids on lettuce (Lactuca sativa) growth and physiology. Lettuce was cultivated in 17cm tall pots filled with the soil amendments of biosolids compost in concentrations of 1%, 3%, 5%, and 7% (v/v) over a 60-day period. Comprehensive data collection includes measurements of plant height, leaf chlorophyll content, photosynthetic gas exchange, leaf area index (LAI), fresh and dry plant biomass, visual ratings, and spectral reflectance data at 340-2500 (nm) with a portable spectroradiometer. Data analysis of weekly and post-harvest collected data analyzed the implications of biosolid usage in agriculture, shedding light on significant effects on crop productivity, soil health, and agricultural sustainability. Keywords: Biosolids, Organic Fertilizer, Soil Contaminants, Lettuce (Lactuca sativa), Plant Physiology, Agricultural Systems
Speakers
MT

MADELEINE TENNY

Florida Gulf Coast University
Co-authors
JG

John Griffis

Florida Gulf Coast University
NA
Wednesday September 25, 2024 3:55pm - 4:05pm HST
South Pacific 4

3:59pm HST

Ornamental Plant Breeding 2 (OPB 2)
Wednesday September 25, 2024 3:59pm - 5:00pm HST
QTL and Transcriptomic Analysis of Fragrance in the Auto-tetraploid Rose Population - Haramrit Gill
Assessing Micropropagation Traits in Anthurium Towards Breeding and Cultivar Development - Jaclyn Nicole Uy
Genotype Comparisons of Anthurium In Vitro Shoot Production in RITA® Bioreactors - Jacob Olarti
Treatment with Oryzalin Induces Chromosomal Changes in Salvia coccinea and Salvia splendens - John Ruter
Moderator
TA

Teresita Amore

University of Hawaii
Wednesday September 25, 2024 3:59pm - 5:00pm HST
South Pacific 2

3:59pm HST

Weed Control and Pest Management 2/Invasive Plants Research (WCPM 2/IPR)
Wednesday September 25, 2024 3:59pm - 5:45pm HST
Planting-hole Steam Application for Pathogen and Weed Control in Organic Strawberry in Southern California - Oleg Daugovish
Elucidating the Impact of Anaerobic Soil Disinfestation on Organic Watermelon Production in South Carolina - Sohaib Chattha
Alternative Carbon Sources for Anaerobic Soil Disinfestation in California Strawberry - Oleg Daugovish
Sweetpotato (Ipomoea batatas) Variety Tolerance to Different Herbicidal Weed Control Methods - Alyssa Miller
Soil Steaming: A Sustainable Weed Management Strategy in Sweetpotato - Alaina Richardson
Assessment of Various Carbon Sources for Anaerobic Soil Disinfestation to Manage Weeds in Organic Sweetpotato - Simardeep Singh
Evaluation of saturated steam with boiling water to control Guinea grass (Megathyrus maximus) in riparian
Moderator
HL

Hannah Lutgen

Extension Faculty, CTAHR
Wednesday September 25, 2024 3:59pm - 5:45pm HST
South Pacific 3

4:00pm HST

OPB 2 - QTL and Transcriptomic Analysis of Fragrance in the Auto-tetraploid Rose Population
Wednesday September 25, 2024 4:00pm - 4:15pm HST
For centuries, roses have been treasured for their therapeutic, cosmetic, and ornamental qualities. Among its many qualities, flower fragrance holds significant economic value. Over 400 volatile compounds contribute to the complex aroma of roses, with terpenoids, phenylpropanoids, and benzenoids playing dominant roles. Among these, geraniol, a monoterpene, contributes notably to the signature scent of rose oil. However, the fragrance of modern roses has gradually diminished as breeders have focused on enhancing other traits like appearance, adaptation, durability, and vase life. To gain a better molecular understanding of specialized metabolic pathways related to floral scent in roses we carried out QTL studies in the SWxBE autotetraploid rose population [Rosa L. ‘ORAfantanov’ (Stormy Weather™) x Rosa L. ‘Radbrite’ (Brite Eyes™)]. Our study suggests that the QTL for the fragrance was identified on chromosome 2 which colocalized with the genes involved with fragrance such as ODO1, EOBIII, and NUDIX. Two rose genotypes from the SWxBE population, ‘16401-N055’ (slightly fragrant) and ‘16089-N051’ (highly fragrant), were used for transcriptomic analysis. Gene expression analysis suggests that the monoterpenoid pathway was highly active in the highly fragrant rose with the NUDIX gene being highly expressed. Thus, NUDIX, a gene involved in geraniol biosynthesis, is a strong candidate gene for the QTL on chromosome 2. This study lays the groundwork for further exploration of the molecular pathways responsible for the scent of roses.
Speakers
HG

Haramrit Gill

University of California, Davis
NA
Co-authors
DB

David Byrne

Texas A
NA
JL

Jeekin Lau

US Department of Agriculture
NA
Wednesday September 25, 2024 4:00pm - 4:15pm HST
South Pacific 2

4:00pm HST

POM 2/HPRB/IPR - Common Mechanisms Controlling Fruit Shapes may be Mediated by Changes in Cell Wall Properties
Wednesday September 25, 2024 4:00pm - 4:15pm HST
Fruit shape variation is abundantly present in horticultural crops. This variation is critical to highlight the market class as well as the culinary purpose of the produce. Many of the underlying genes have been cloned in tomato, offering insights into the molecular mechanisms of morphological diversity. Specifically, members of the OFP, TRM and SUN family regulate produce shape variation in tomato and other crops, thereby highlighting the importance of these three families in regulating phenotypic diversity. Despite the knowledge of the genes, mechanistic insights into the function of members of these three gene families are lacking. Our research on the tomato genes OVATE and OFP20 has shown that changes in produce shapes are noticeable early in the development of the flower. Cell counts in ovaries at anthesis implied that changes in cell division patterning may underlie morphological diversity. However, gene expression studies showed that morphological changes were associated with cell wall processes and not with changes in cell division patterning.
Speakers
EV

Esther van der Knaap

University of Georgia
Co-authors
YW

Yanbing Wang

University of Georgia
NA
Wednesday September 25, 2024 4:00pm - 4:15pm HST
Nautilus 1

4:00pm HST

WCPM 2/IPR - Planting-hole Steam Application for Pathogen and Weed Control in Organic Strawberry in Southern California
Wednesday September 25, 2024 4:00pm - 4:15pm HST
Organic strawberry production has been expanding in California, but opportunities for crop rotation are limited due to lack of organically certified fields. Continuous strawberry production promotes soil-borne pathogens, such as Macrophomina phaseolina, the causal agent of charcoal rot and increases populations of weeds. These problems are exacerbated by lack of cost-effective management tools. In summer and fall production seasons at Oxnard, CA we evaluated pre-plant steam injection to raise soil temperature to 70 C or above for at least two minutes. Steam generated on-site was applied via four 25-cm long spikes to planting holes in raised beds covered with the plastic mulch. Five to ten days later, bare-root strawberry plants were placed in six steamed and six untreated plots and their performance and fruit production assessed. Additionally, we collected soil at 0-25 cm for analyses of resident Macrophomina phaseolina abundance before and after treatment and evaluated weed densities in planting holes. Steam application reduced M. phaseolina microsclerotia levels 80% in summer and 96% in fall. Steaming provided near 100% control of weeds germinated from the soil seed bank, but had no effect on germination of wind-dispersed weeds deposited to holes after steaming as was the case with fumigants. In summer season, strawberry mortality due to soil-borne pathogens was 12-18% in steamed plots and 70-75% in untreated soil. Due to loss of plants, marketable fruit yields in untreated plots were reduced 95% compared to steam treatment. No early-season plant mortality occurred in fall season but strawberry plants were 39 and 54% larger at two evaluation dates in steamed plots compared to untreated soil. We continue evaluations of fruit production and plant responses to soil pathogens. The completed work suggests that hole steaming may be very effective in suppressing soil-borne pathogens and weeds interfering with organic strawberry production in coastal California.
Speakers
OD

Oleg Daugovish

University of California Cooperative Extension
Co-authors
JB

Jenny Broome

UC Davis
NA
KI

Kelly Ivors

Driscolls
NA
OB

Oddbjorn Bergem

SoilSteam
NA
PH

Peter Henry

USDA-ARS
NA
Wednesday September 25, 2024 4:00pm - 4:15pm HST
South Pacific 3

4:00pm HST

Early Career Competition
Wednesday September 25, 2024 4:00pm - 5:00pm HST
Moderator
BS

Becky Sideman

Member-At-Large
Wednesday September 25, 2024 4:00pm - 5:00pm HST
Hibiscus 1

4:00pm HST

AI Innovation for Horticulture - Part 2
Wednesday September 25, 2024 4:00pm - 6:00pm HST
Introduction and Overview

Speaker: Kathryn Orvis
Professor
Department of Horticulture and Landscape Architecture
Purdue University
625 Ag Mall Drive
West Lafayette, IN 47907-2010

Title: Digital Agriculture and AI on Specialty Crops Production

Description: Digital agriculture is the 4th agricultural revolution and Artificial Intelligence (AI) is part of it. Currently, in the "connected agriculture"; era, many technologies have been released on the marked regarding the use of multispectral
sensors for many purposes in agriculture. This talk is going to cover information on how to use Digital Agriculture online platforms to process multispectral imagery, and how AI can be used to collect individual in-field plant data.

Speaker: Luan Pereira de Oliveira
Assistant Professor and Precision Agriculture Extension Specialist
Department of Horticulture
University of Georgia
139 Engineering Building
2329 Rainwater Road
Tifton, GA 31793

Title: Bringing the Future of AI to the Farm.
Description: In this talk, we will cover the multitude of use cases where AI can be applied in farming – from weed detection and robotics to Generative AI-based farm assistants and Virtual Reality. We go through the industry trends of applied Artificial Intelligence and think big about farm automation for the future.

Speaker: Justin Hoffman
Chief Technology Officer of AgTechLogic


Title: From Concept to Impact: The Evolution of Moss Robotics through Industry-
University Collaboration


Description: Moss Robotics' journey began with a project focused on autonomous driving technology for tree nurseries, born out of a collaboration between Carnegie Mellon University, Robotics Institute and Hale; Hine Nursery in Tennessee. In this talk, we share the story of how we discovered the real value our solution could offer to growers, and how we refined our ideas through continuous iteration. This process transformed moss robotics from a simple concept into the company it is today. We will cover the steps of our evolution, emphasizing the practical benefits of combining academic research with industry needs to innovate effectively. Additionally, we look ahead to how emerging technologies might further influence our growth and the agricultural industry as a whole, aiming for advancements in farming practices that are both technologically sophisticated and grounded in real-world applications.

Speaker: Di Hu
Founder and CEO
Moss Robotics

Title: AI-Enhanced Computer Vision for Crop Monitoring in Controlled Environment
Agriculture


Description: Controlled environment agriculture (CEA) production remains expensive due to high operation costs. Growers can reduce production costs by nurturing crops with data, however, the data is highly diverse, and growers lack the expertise to analyze this data to derive actionable insights for informed decision-making. In addition, traditional crop monitoring is carried out manually, which makes it unfeasible to collect data daily to get actionable insights for high yields. Recent advancements in sensing and computing technologies, such as AI, computer vision, edge computing, and edge-
cloud integration, have opened opportunities to develop data-driven technologies to enhance decision-making capabilities. Integrating AI and computer vision technologies has emerged as a transformative toolset that can collect real-time plant data at high spatial and temporal resolutions, pivotal in optimizing resource management and maximizing production. The CE Engineering lab delves into cutting-edge computer vision applications within CEA, focusing on various applications, including phenotyping leafy greens, yield estimation, disease monitoring, and plant spacing optimization. This presentation will explore the details of lettuce phenotyping, disease classification, strawberry fruit classification, and yield estimation. We will delve into the technical aspects of these algorithms, including image processing techniques, machine learning models, and data integration strategies. This presentation will showcase state-of-the-art deep learning approaches, including segmentation algorithms, model training, and deep classifiers. Overall, this presentation aims to provide insights into the transformative potential of computer vision in CEA, offering a glimpse into the future of data-driven and sustainable CE production.

Speaker: Azlan Zahid
Assistant Professor,
Department of Biological and Agricultural Engineering
Texas A&M AgriLife Research
Texas A&M University System
Dallas, TX 75252, USA


Panel: 30-minute panel with the above speakers, to allow time for Q&A and discussion.
Moderator Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
KO

Kathryn Orvis

Professor, Purdue Univ
DH

Di Hu

CEO, moss robotics inc.
avatar for Justin Hoffman

Justin Hoffman

Chief Technology Officer, AgTechLogic
Wednesday September 25, 2024 4:00pm - 6:00pm HST
Coral 3

4:00pm HST

Interest Group Session: Choosing the Right Career Path-Research, Extension, Teaching, and Administration
Wednesday September 25, 2024 4:00pm - 6:00pm HST
The agricultural production system and the education system in Indian subcontinent and US are very different. Thus, students and post docs coming to US to pursue research and career encounter dilemma and challenges in selecting right career path. For example, in Indian subcontinent higher emphasis is given to research and teaching whereas extension and administration are not fully understood. The goal of this special session will be for students to have open dialogues with experts in the field of research, extension, teaching, and administration with Indian sub-continent background, so the panel understands the challenges faced by incoming students. This session will benefit all the graduate students and researchers who are preparing to for the next step in career.

Coordinator(s)
  • Tripti Vashisth, University of Florida, Lake Alfred, United States
Speaker/Participant(s)
  • Bhimu Patil, Texas A&M University, Vegetable and Fruit Improvement Center, College Station, Texas, United States
  • Ajay Nair, Iowa State University, Ames, Iowa, United States
  • Rammohan Uckoo, Texas A&M University, College Station, Texas, United States
  • Rajasekaran Lada, Dalhousie University, Truro, Nova Scotia, Canada

Wednesday September 25, 2024 4:00pm - 6:00pm HST
South Pacific 1

4:00pm HST

Interest Group Session: Using Applied Economics to Explore the Many Facets of Adding Value to the Horticultural Industry
Wednesday September 25, 2024 4:00pm - 6:00pm HST
The business environment in the horticultural industry is evolving and consumer preferences for value-added products are shaping market trends. With an increasing emphasis on health, sustainability, and convenience, consumers are seeking horticultural products that offer added value and benefits. This shift in consumer preferences presents both challenges and opportunities for horticultural businesses. Understanding these evolving consumer demands is crucial for horticulture businesses to develop innovative products and marketing strategies that resonate with their target audience.

The session aims to explore consumer behavior and preferences for value-added horticultural products, providing attendees with valuable insights to inform strategic decision-making and drive business growth in the competitive market. Presentations will explore the specific information consumers seek on wine packages and labels, and the influence of state marketing programs on consumer preferences for tomato transplants. Additionally, the session will explore the return on investment of social media marketing for US green industry firms, consumer preferences and willingness to pay for Florida-grown fresh blueberries, strategies for expanding marketing potential to appeal to all horticulture consumers, and the influence of demographics on the perception of flatheaded borer damage on ornamental plants. Through these diverse presentations, attendees will gain insights into key factors shaping consumer behavior, industry dynamics, and marketing strategies in the horticulture sector.

Coordinator(s)
  • Alicia L Rihn, University of Tennessee, Knoxville, United States
  • Melinda Knuth, North Carolina State University, Horticultural Science, Raleigh, North Carolina, United States
  • Chengyan Yue, University of Minnesota-Twin Cities (Minneapolis, MN), St. Paul, Minnesota, United States
Moderator(s)
  • Alicia L Rihn, University of Tennessee, Knoxville, United States
  • Melinda Knuth, North Carolina State University, Horticultural Science, Raleigh, North Carolina, United States
Speaker/Participant(s)
  • Alicia L Rihn, University of Tennessee, Knoxville, United States
    Do State Marketing Programs Impact Consumer Preferences for Tomato Transplants? (15 mins)
  • Ariana P Torres, Purdue University, United States
    The Return of Investment of Social Media Marketing: A Case of U.S. Green Industry Firms (15 mins)
  • Chengyan Yue, University of Minnesota-Twin Cities (Minneapolis, MN), St. Paul, Minnesota, United States
    What Information Consumers Are Looking for On Wine Packages and Labels? (15 mins)
  • Hayk Khachatryan, University of Florida, United States
    Analyzing Consumer Preferences and Willingness to Pay for Florida-Grown Fresh Blueberries (15 mins)
  • Melinda Knuth, North Carolina State University, Horticultural Science, Raleigh, North Carolina, United States
    Expanding Marketing Potential to Appeal to All Horticulture Consumers (15 mins)
  • Ben Campbell, University of Georgia, United States
    Demographic Influences on the Perception of Flatheaded Borer Damage on Ornamental Crops (15 mins)
    Summary: Mounata Dahal, Tate Norman, Ben Campbell, and Alicia Rihn
Moderator
MK

Melinda Knuth

North Carolina State University
Speakers
BC

Ben Campbell

University of Georgia
CY

Chengyan Yue

University of Minnesota-Twin Cities (Minneapolis, MN)
Wednesday September 25, 2024 4:00pm - 6:00pm HST
Coral 1

4:14pm HST

CE 2 - Growth Chambers and Controlled Environments 2 (Posters)
Wednesday September 25, 2024 4:14pm - 5:45pm HST
Carbohydrate Synthesis and Freeze Tolerance of Clonal-type Bermudagrasses as Affected by Mowing Heights During Cold Acclimation and Deacclimation Process - Mingying Xiang
Understanding Photoperiod Effects on Seek and Seedling Quality in Soybean Speed Breeding- Christiane da Silva
Identifying the Optimal Range of pH Management for Hydroponic Leafy Vegetables - Yujin Park
Enhancing Iron Bioavailability in Hydroponic Leafy Greens by Iron Chelators - Asmita Nagila
Effects of Mycorrhiza and Ciochar Interactions on Geraniums - Teal Hendrickson
Exploring Different Nutrient Solution Quantities to Optimize Quantity and Quality in Hydroponic Production - Puja Subedi
The Effect of Climate Change on Plants: A Case Study with Wheat - Kira Webster
How Does Supplementing Dissolved Oxygen Impact Hydroponic Strawberry Production? - Jonathan Ries
Exploring Different EC Levels to Optimize Quantity and Quality in Hydroponic Production - Puja Subedi

Wednesday September 25, 2024 4:14pm - 5:45pm HST
Coral 2

4:15pm HST

CE 2 -Carbohydrate Synthesis and Freeze Tolerance of Clonal-type Bermudagrasses as Affected by Mowing Heights During Cold Acclimation and Deacclimation Process
Wednesday September 25, 2024 4:15pm - 4:25pm HST
Bermudagrass (Cynodon spp.) is a prominent warm-season turfgrass extensively utilized across golf courses, athletic fields, home lawns, and recreational areas due to its excellent heat tolerance, good traffic tolerance, and strong recuperative potential. Despite its strengths, winter survivability in colder climates remains a concern. Research has revealed variations in freeze tolerance across bermudagrass cultivars, yet there's a gap in understanding the underlying physiological mechanisms and the impact of cold acclimation and deacclimation processes. Additionally, the influence of mowing height on carbohydrate synthesis and freeze tolerance has been reported. To address these gaps, a study utilizing turfgrass plugs from different acclimation stages was conducted in a freeze chamber. The objective of this study was to examine freeze tolerance and carbohydrate synthesis in four clonal-type bermudagrass varieties ('Tifway’, ‘Tahoma 31’, ‘Astro’, and ‘TifTuf’) under mowing heights of 0.5” and 1.5” across various cold acclimation and deacclimation stages. The plugs were subjected to soil temperatures ranging from -5°C to -12°C, with survival assessed after three weeks to determine the lethal temperature (LT50) for each condition. Rhizome carbohydrate levels at each stage were determined. The correlation between rhizome carbohydrate level and freeze tolerance was determined. The data from this study is currently being analyzed.
Speakers
MX

Mingying Xiang

Oklahoma State University
Co-authors
DM

Dennis Martin

Oklahoma State University
NA
LZ

Lu Zhang

Oklahoma State University
SY

Shuhao Yu

Oklahoma State University
YS

Yanwei Sun

Oklahoma State University
NA
Wednesday September 25, 2024 4:15pm - 4:25pm HST
Coral 2

4:15pm HST

OPB 2 - Assessing Micropropagation Traits in Anthurium Towards Breeding and Cultivar Development
Wednesday September 25, 2024 4:15pm - 4:30pm HST
The major bottleneck in anthurium cultivar release is the availability of microprogated plants for field testing. Genotype has been a major consideration for anthurium protocol development. Different genotypes vary in in vitro performance even when using optimized media, therefore assessing proliferative variation under in vitro conditions could help identify cultivars that could introgress tissue culture traits and provide guidelines for future protocol development. The objective of this study is to assess the in vitro performance of different anthurium accessions from the University of Hawaii anthurium breeding program under the RITA® temporary immersion system and to observe how lineage affects in vitro performance. To evaluate shoot initiation/proliferation, 20 accessions of anthurium (parents, interspecific hybrids, complex hybrids, and wild relatives) were placed in RITA® supplemented with a liquid medium containing 0.3X MS salts with 0.2 mg/L BA, 15% coconut water and 20 g/L sucrose. Primary shoots were excised after 45 days to allow axillary buds to develop into secondary shoots. Bud masses (trimmed explant bases) were placed on a solid medium containing ½ MS salts with 15% coconut water, 20 g/L sucrose and 2g/L gellan gum to observe shoot proliferation and growth. Parameters were analyzed using mixed models with time block as random effects and accessions as fixed effects. Previously identified check cultivars (‘Marian Seefurth’ and ‘New Pahoa Red’) were used as controls in this study. Significant differences among the genotypes were observed in terms of the number of primary shoots, the number of secondary shoots, total axillary bud mass volume (cm3), number of explants with shoot, and number of explants with roots. Three selections and an accession were identified to have potential use for breeding. UH2053, UH2409, UH2327 and ‘New Pahoa Red’ showed superior or comparable number of primary and secondary shoots, explant volume, and rooting compared to the check cultivars. These lines will be considered as parents in future crosses for cultivar development. Cluster analysis was also performed and was cross-referenced to existing pedigree and breeding records. Our analysis revealed five clusters which indicate that that parentage influenced in vitro shoot production particularly in lines with Anthurium andraeanum, A. amnicola, A. formosum and A. kamemotoanum in their background. Pedigree and breeding records are valuable resources for predicting response profiles of anthurium in vitro performance.
Speakers
JN

Jaclyn Nicole Uy

University of Hawaii
Co-authors
JO

Jacob Olarti

University of Hawaii
NA
TA

Teresita Amore

University of Hawaii
Wednesday September 25, 2024 4:15pm - 4:30pm HST
South Pacific 2

4:15pm HST

POM 2/HPRB/IPR - Pomological Nomenclature: Recent Developments and Problems
Wednesday September 25, 2024 4:15pm - 4:30pm HST
In addition to botanical names, at least a dozen distinct categories of nomenclature are applied to plant cultivars, including various forms of cultivar denominations, breeders references, and trade names. Two sets of rules, the International Code of Nomenclature for Cultivated Plants (9th ed., 2016), and the Explanatory Notes on Variety Denominations Under the UPOV Convention (2022) provide current guidelines for plant cultivar nomenclature. In some instances UPOV and ICNCP rules differ, and stakeholders may wish to consider whether it would be feasible to seek harmonization, and the mechanisms by which that might be achieved. This session will trace a brief history of cultivar denomination rules for U.S. plant patents. The United States Patent and Trademark Office, which issues plant patents, does not provide detailed nomenclatural guidelines. In the past two decades a new model for plant nomenclature has prevailed, in which an alphanumeric code serves as the official cultivar denomination, and this is paired with a trademark, either registered or unregistered. The relationship between cultivar denominations and trade names can be complex and fluid. As co-editor of the Register of New Fruit and Nut Cultivars, the presenter professionally researches all new pomological cultivar denominations and trade names, to avoid publishing names that conflict with previous names or nomenclatural standards. The establishment of an official cultivar denomination has important practical consequences that are sometimes ignored by breeders and rights owners. When a cultivar has been granted a plant patent or plant breeders’ rights, the cultivar denomination recorded by the statutory plant registration authority that issues the grant becomes officially established (a “statutory epithet”), and cannot be casually changed or replaced by the rights owner. When such informal synonyms are used, they are best regarded as trade names, often as unregistered trademarks. Common mistakes and pitfalls in nomenclature are described.
Speakers
DK

David Karp

University of California, Riverside
Wednesday September 25, 2024 4:15pm - 4:30pm HST
Nautilus 1

4:15pm HST

WCPM 2/IPR - Elucidating the Impact of Anaerobic Soil Disinfestation on Organic Watermelon Production in South Carolina
Wednesday September 25, 2024 4:15pm - 4:30pm HST
Weeds and soil-borne pathogens are limiting factors in organic watermelon (Citrullus lanatus) production. Yellow nutsedge (Cyperus esculentus) is a problematic weed for Southeastern watermelon growers. Fusarium wilt caused by Fusarium oxysporum f.sp. niveum (FON), is responsible for significant yield loss in watermelon production. Inefficient non-chemical tactics are an impediment to curtail weeds and soil-borne diseases in organic watermelon; and necessitate the adaption of an alternative strategic and holistic approach. Anaerobic soil disinfestation (ASD) has the potential to control weeds and soil-borne pathogens across a range of environments and crop production systems. ASD is a preplant chemical independent technique, which requires incorporation of labile organic carbon (C) sources into the soil, followed by tarping the soil with plastic mulch, and irrigating the soil to the saturation. Shifts in soil microbial communities and production of volatile organic compounds during ASD process are the main mechanisms that are believed to kill soil-borne pathogens and weeds seeds. The objectives of this study were to 1) determine whether ASD can suppress the emergence of yellow nutsedge, 2) compare the efficacy of locally available C sources, 3) evaluate if ASD can influence grafted and non-grafted watermelon yield. A field trial was conducted at Clemson University’s, Coastal Research and Education Center in Charleston, South Carolina in 2023. The study was arranged in a randomized complete block design with four replications. Main C sources were subjected to control (CT) with no C, chicken manure molasses (CMM), and cotton seed meal (CSM). All treatments were assigned as ASD with non-grafted (Powerhouse) and grafted (Carolina strongback) rootstock grafted to scion Powerhouse. Indicators of reduction in soils (IRIS) tubes paint removal (%), yellow nutsedge shoot count, and crop yield data were recorded. Higher anaerobic soil conditions and lower yellow nutsedge shoot count were observed in ASD plots. At the time of watermelon harvest, total number of yellow nutsedge shoot count were recorded as 65, 25, and 22 in CT, CSM, and CMM, respectively. Higher marketable fruit yield was recorded in ASD plots treated with CMM. Based on weed control and yield assessments, CMM to facilitate ASD is an ideal practice for growing organic watermelon in South Carolina.
Speakers
avatar for Sohaib Chattha

Sohaib Chattha

Graduate Research Assistant, Clemson University
Co-authors
BW

Brian Ward

Clemson University
MC

Matthew Cutulle

Clemson University
Wednesday September 25, 2024 4:15pm - 4:30pm HST
South Pacific 3

4:25pm HST

CE 2 - Understanding Photoperiod Effects on Seed and Seedling Quality in Soybean Speed Breeding
Wednesday September 25, 2024 4:25pm - 4:35pm HST
Soybean is a short-day plant, which means that days must be shorter than a critical value to induce flowering. Manipulating the photoperiod regime is a well-known way to shorten plant cycles in speeding breeding programs. However, the impact of the photoperiod on the quality of the produced seeds is not well understood. Here, we investigate how photoperiod affected the seed and seedling quality in soybean plants, grown in a controlled environment. Soybean (Glycine max) plants (var. S16-14801C and CZ7570LL) were grown in growth chambers with controlled temperature (27 ± 0.5˚C), CO2 (475 ± 15 µmol mol-1), humidity (70 ± 5.0%), and light (300 ± 5 µmol m-2 s-1 at table; 20% blue,10% green, 70% red). One week after germination, seedlings were exposed to different photoperiod regimes: i) 10 h (0 w at 18 h), ii) two weeks at 18 h and then 10 h (2 w at 18 h), iii) four weeks at 18 h and then 10 h (4 w at 18 h); iv) six weeks at 18 h and then 10 h (6 w at 18 h). The plants were grown in the described treatments until the R8 stage (95% brown pods), without changing the light fixture height (industry standard practice). A sample of seeds was harvested and analyzed regarding quality while other samples were placed to germinate in seed germination paper to evaluate germination rate and seedling growth for 10 days. Similar results were found for both varieties; plants of all treatments presented different heights, in which plants at 0 w at 18 h were shorter (50 cm) and 6 w at 18 h taller (180 cm). Treatments did not affect the moisture or weight of 100 seeds. Conversely, germination and seedling survival were 30% lower in seeds from plants 0 w at 18 h than in other treatments. Similar results were found for the root (13% lower in 0 w at 18 h) and shoot length (19% lower in 0 w at 18 h) of seedlings. However, the dry weight of seedlings was similar among treatments. Manipulating the photoperiod can speed up the plant cycle and is a good alternative for speed-breading programs. However, extreme photoperiods and low daily light integral can produce seeds and seedlings with lower quality that can influence the production of plants of the next generation.
Speakers
avatar for Cristiane da Silva

Cristiane da Silva

Postdoctoral Research Scholar, North Carolina State University
I'm Cristiane, a plant physiologist with experience in plant biochemistry and plant responses to abiotic stress. Currently, I'm a post-doc at NCSU studying the effects of light on plant life cycles to expedite breeding purposes in crop and tree species. When I'm not working, I enjoy... Read More →
Co-authors
CC

Cristian Collado

North Carolina State University
NA
RH

Ricardo Hernandez

North Carolina State University
NA
Wednesday September 25, 2024 4:25pm - 4:35pm HST
Coral 2

4:29pm HST

Commercial Horticulture/ Federal Partners (CHEX/FP)
Wednesday September 25, 2024 4:29pm - 5:10pm HST
Advances in Phytophthora, Pythium, and Phytopythium Species Detection, Isolation, Culture, Diagnostics, and Virulence Rejuvenation - Timothy Waller
Effect of Planting Date on Strawberry Yield - Samantha Simard
Evaluation of Irrigation Strategies in Watermelons - Juan Enciso
Moderator
TW

Timothy Waller

Rutgers, The State University of New Jersey
Timothy J Waller, Ph.D. is serving in his fourth year as the Commercial Nursery Agent of Rutgers Cooperative Extension in southern NJ, based out of Cumberland County. Tim has a Ph.D. in Plant Biology with a focus on fungal plant pathology and has been a licensed pesticide applicator... Read More →
Wednesday September 25, 2024 4:29pm - 5:10pm HST
Lehua Suite

4:30pm HST

CHEX/FP - Evaluation of Irrigation Strategies in Watermelons
Wednesday September 25, 2024 4:30pm - 4:40pm HST
The Lower Rio Grande Valley farmers traditionally irrigate vegetable crops with furrow irrigation systems. To conserve water and mitigate the effects of droughts, there is a need to adopt more efficient irrigation and fertilization methods and practices in vegetable crops to increase crop production quality and profitability. Farmers that use furrow irrigation systems apply from 4 to 6 inches per irrigation depending on their furrow length and apply more than five irrigations during the vegetable growing season, and using between 20 inches (1.7 ac-ft) and 40 inches (3.3 ac-ft) of irrigation water in their fields. Vegetables have a shallow root system, so farmers must irrigate frequently to maintain good moisture levels during the growing season for optimum growth, possibly wasting water. We use image analysis derived from Unmanned Aerial Systems (UAS) and irrigation soil water sensors to provide management recommendations to schedule drip and surface irrigation to conserve additional amounts of water. We established replicated research experiments using subsurface drip irrigation and soil water sensors (watermark sensors) to irrigate watermelons and other vegetable crops. We grew plants under three different water levels to trigger irrigation (50, 75, and 100 cb). A drip irrigation system with plastic mulch was placed in the field, as well as soil-water sensors, to measure and monitor the soil moisture. After calculating the water used in the three water level treatments, the 50 cb treatment used 0.27 ac-ft, the 75 cb treatment used 0.24 cb and 0.22 ac-ft was used by the 100 cb treatment. According to our results, we could conserve up to 3.0 ac-ft with our recommendations. We concluded that watermelons could be managed when the soil-water sensor readings range between 50 and 75 CB and approximately 0.3 ac-ft of water using subsurface drip irrigation. We obtained an average yield of 53,536 lb/ac, when irrigated under the 50 cb treatment, 42,059 lb/ac at 75 cb, and 36,719 lb/ac at 100 cb.
Speakers Co-authors
Wednesday September 25, 2024 4:30pm - 4:40pm HST
Lehua Suite

4:30pm HST

OPB 2 - Genotype Comparisons of Anthurium In Vitro Shoot Production in RITA® Bioreactors
Wednesday September 25, 2024 4:30pm - 4:45pm HST
Anthuriums are Hawaii’s top cut flower with its sales valued at USD1.6 M in 2022. It is an important floriculture crop as it is both used as cut flower and foliage. Development of new genotypes allows the growers in Hawaii to produce new cultivars desired by the market. The University of Hawaii anthurium breeding program has identified new selections to field test with commercial growers. In order to do so, the breeding program propagates these selections to send to growers. Recently the use of bioreactors, such as RITA® on ‘New Pahoa Red’, resulted in three times more shoot production than in traditional flasks placed on a platform shaker. Shoot and root production and axillary bud mass volume of three new selections, UH2647, UH2651, and UH2652, were compared against the control ‘New Pahoa Red’. Ten nodes of each genotype were placed in a RITA® bioreactor, and replicated five times in a completely randomized design. Nodes were cultured in liquid medium consisting of 0.3MS, 0.1 mg l-1 BA, 15% coconut water, 20 g l-1 sucrose, and 1 ml l-1 NaSiO3. The plants were cultured in the bioreactors for 1.5 months, and then removed to obtain the number of shoots, roots, and axillary bud mass volume. Primary shoots were excised and transferred to 0.3 MS, 15% coconut water, 20 g l-1 sucrose, and solidified with 6 g l-1 Gelzan® to promote axillary bud growth and shoot development. The pH for all media was adjusted to 5.8. One month later, shoots (~0.5 cm in height) were excised from the axillary bud masses. Shoot counts excised after initial culture in the liquid medium and after placement in the shoot development solid medium were analyzed using one-way ANOVA on R studio. Axillary bud mass volume and root number were analyzed. UH2647 significantly produced more shoots than UH2652 and ‘New Pahoa Red’, while UH2651 was not different from any genotype. UH2647 also had the highest average axillary bud mass volume. UH2651 and UH2652 produced significantly more roots than the control. Knowing the genotypic differences in shoot production will assist propagation facilities in developing guidelines to schedule production of individual genotypes.
Speakers
JO

Jacob Olarti

University of Hawaii
NA
Co-authors
JN

Jaclyn Nicole Uy

University of Hawaii at Manoa
TA

Teresita Amore

University of Hawaii
Wednesday September 25, 2024 4:30pm - 4:45pm HST
South Pacific 2

4:30pm HST

WCPM 2/IPR - Alternative Carbon Sources for Anaerobic Soil Disinfestation in California Strawberry
Wednesday September 25, 2024 4:30pm - 4:45pm HST
Anaerobic soil disinfestation (ASD) has been adopted in approximately1,000 ha in California strawberry production as an alternative to chemical fumigation of soil. Rice bran, the predominant carbon source for ASD, has become increasingly expensive. In 2022-2024 field studies at Santa Paula and Oxnard, CA we evaluated 20-30% lower-priced wheat middlings (Midds) at 6 or 7 t/acre as alternative carbon sources to rice bran. The ASD treatments were applied in August at each location in preparation for strawberry planting in October. Soil and air temperatures were 18-35 C during that time. After incorporation of carbon sources into the top 30 cm of bed soil, beds were shaped, irrigation drip lines installed and covered with totally impermeable film (TIF) to prevent gas exchange. Beds were irrigated to full capacity within 24 to 72 hours after TIF installation. Anaerobic conditions were measured with oxidation reduction potential (ORP) sensors placed at 15 cm depth. Midds plots maintained Eh at -180 to 0 mV during the two ASD weeks at Santa Paula and -300 to 0 mV during five weeks at Oxnard, while untreated soil was aerobic at 200 to 400 mV. At Santa Paula, permeable bags with inoculum of Macrophomina phaseolina, a key soil borne pathogen of strawberry, and tubers of Cyperus esculentus, the most difficult to control weed, were placed 15 cm deep in soil and retrieved two weeks after ASD initiation for analyses. At Oxnard, resident populations of M. phaseolina and C. esculentus in soil were assessed before and after ASD. Two weeks after the completion of ASD, holes were cut to aerate beds and bare-root strawberry were transplanted into them: ‘Fronteras’ at Santa Paula and ‘Gaviota’ at Oxnard. ASD with Midds reduced viable microsclerotia of M. phaseolina 75% at Santa Paula and 98% at Oxnard. ASD treatments reduced tuber germination of C. esculentus 68-74% compared to untreated soil. Additionally, Midds and DDG provided greater sufficiency of plant-available nitrogen and increased fruit yields 40%, compared to untreated soil at Santa Paula. We continue fruit production evaluations at Oxnard in 2024. ASD with wheat middlings as a carbon source can suppress soil pathogens and weeds and help sustain organic strawberry production in California.
Speakers
OD

Oleg Daugovish

University of California Cooperative Extension
Co-authors
PH

Peter Henry

USDA-ARS
NA
Wednesday September 25, 2024 4:30pm - 4:45pm HST
South Pacific 3

4:35pm HST

CE 2 - Identifying the Optimal Range of pH Management for Hydroponic Leafy Vegetables
Wednesday September 25, 2024 4:35pm - 4:45pm HST
In hydroponics, the pH of the nutrient solution influences the solubility and availability of essential nutrients. The optimal pH for plant nutrient uptake in many crop species is around 6.0. However, the impacts of precise pH management on plant nutrient uptake, crop yield, and the optimal pH range remain less clear. In this study, we investigated the effects of pH management range on plant nutrient uptake and the growth of hydroponic leafy vegetables. Within an indoor vertical farm, we grew lettuce (Lactuca sativa) 'Rex,' kale (Brassica oleracea var. sabellica) 'Red Russian,' and arugula (Eruca sativa) 'Astro' using deep water culture hydroponics at the air temperature of 22 °C under a photosynthetic photon flux density of 200 μmol∙m−2∙s−1 with a 24-h photoperiod. The experiment included six pH treatments: pH 6, 6±0.5, 6±1.0, 6±1.5, 6±2.0, and without pH control. Compared to managing pH at 6, maintaining pH within 6±1.0 had generally similar impacts on leaf number, leaf area, SPAD index, shoot and root fresh mass, and shoot and root dry mass in all three crops. However, when compared to managing pH at 6, maintaining pH at 6±1.5 or greater reduced leaf area (by 32-47% in lettuce, by 30-41% in kale, or by 56-65% in arugula) and shoot fresh mass (by 33-54% in lettuce, by 37-45% in kale, or by 48-64% in arugula). Furthermore, in comparison to managing pH at 6, maintaining pH at 6±1.5 or greater also decreased leaf number in lettuce by 3-5 leaves and in arugula by 13-15 leaves but increased the root fresh mass of lettuce by 26-43%. Our results suggest that maintaining pH within 6±1.0 can be effective in promoting optimal nutrient uptake and overall plant development in the context of hydroponic cultivation.
Speakers
YP

Yujin Park

Arizona State University
Co-authors
ME

Matthew Easter

Arizona State University
NA
ZC

Zhihao Chen

Arizona State University
NA
Wednesday September 25, 2024 4:35pm - 4:45pm HST
Coral 2

4:40pm HST

CHEX/FP - Advances in Phytophthora, Pythium, and Phytopythium Species Detection, Isolation, Culture, Diagnostics, and Virulence Rejuvenation
Wednesday September 25, 2024 4:40pm - 4:50pm HST
Not only are Phytophthora, Pythium, and interesting Phytopythium species potentially devastating horticultural pathogens, they regularly present challenges in vitro. In this study, multiple established and novel methodologies were built upon to bolster researchers’ ability to quickly isolate, differentiate, and promote virulence of multiple oomycetes principally collected from symptomatic conifers and nearby water sources. These methods allow greater flexibility in generating clean mycelial cultures for genetic characterization, varying pathogen structures for use in novel bioassays (such as synchronized production of sporangia or zoospores), and ultimately inoculations to evaluate oomycide efficacy or make headway towards completion of Koch’s postulates for previously uncharacterized host: pathogen pairings. Phytopythium vexans (Pp. vexans) (n=8 isolates), three Phytophthora species / species complexes including P. cinnamomi (n=10), P. cryptogea / drechsleri complex (n=4) and P. humicola (n=2), as well as 5 tentative species of Pythium, were evaluated. Isolations took two forms, standard root sampling onto Phytophthora selective media (PARPH), or water-based sampling through a modified ‘baiting/trapping’ technique that utilized on-site collected water samples in the laboratory. The ‘baits’ were Cannabis sativa seed, Vigna radiata beans, and Rhododendron maximum leaves suspended in aerated water samples or slurry of silt/soil. Samples were evaluated on V8-agar (V8A), pea agar (PA), pea broth (PB), potato dextrose agar (PDA), cornmeal agar (CMA), and water agar (WA), each of which provided distinct morphological indicators and structures useful in diagnostic guides and in bioassays or inoculations. As is typical with all plant pathogens, the longer they remain in culture, the less virulent they may become. With oomycetes, this is compounded as the pathogen will often go into chlamydospore or oospore formation (long lived survival structures) which are not ideal for experimentation. Inclusion of germinated then surface sterilized (70% ethanol for 30s) Vigna radiata and Lupinus perennis sprouts into recently poured (still liquid) 1/8 clarified V8 juice agar (1/8 clV8A) provided a media capable of rejuvenating the pathogen due to presence of living roots and dynamic plant nutrients. This allows for more predictability of zoospore formation, especially if they are intended to be used with a time sensitive trials. In numerous incidences multiple species of Phytophthora and Phytopythium vexans isolates went into zoospore release simultaneously by utilizing these approaches in combination with resource starvation and culture washing with sterile distilled water. Taken together these approaches will greatly aid any researcher working with root disease oomycetes in culture.
Speakers
WE

William Errickson

Rutgers University
Wednesday September 25, 2024 4:40pm - 4:50pm HST
Lehua Suite

4:45pm HST

CE 2 - Enhancing Iron Bioavailability in Hydroponic Leafy Greens by Iron Chelators
Wednesday September 25, 2024 4:45pm - 4:55pm HST
Iron is an essential micronutrient for the growth and development of both plants and humans, as it plays vital roles in processes such as protein synthesis, respiration and DNA replication. Leafy greens, vital dietary sources of iron, can be cultivated with increased bioavailable iron through hydroponics by customizing nutrient solutions. Conventionally, iron chelates like EDTA and DTPA, are used in hydroponics, but challenges persist in iron acquisition due to their pH dependency as well as quick oxidation to ferric ion which is harder to uptake by plants. Good sources of chelates that respond well to high pH values, like EDDHA, are often more expensive. Studies suggest that iron complexed with humic substances exhibits higher efficiency, though confirmation in large-scale hydroponic systems is still needed. Fulvic acids are water-soluble humic substances with lower molecular weights that hold promise as alternatives or supplements to synthetic chelates, enhancing iron uptake and stress tolerance. Hydroponic systems, such as Deep-Water Culture (DWC) or Nutrient Film Technique (NFT), impact plant growth and nutrient uptake differently based on temperature, EC, and pH. This research compared the effects of various iron chelators on lettuce and kale cultivation in DWC and NFT systems. Results indicate significant yield loss in iron-deficient kale, while iron-chelated solutions enhanced yields. The addition of fulvic acid to EDTA-chelated solutions notably improved kale yield in DWC compared to no iron and EDTA-only solutions. Leafy greens showed higher chlorophyll fluorescence (Fv/Fm ratio) and chlorophyll content in DWC compared to NFT. The results showed species-specific and system-specific responses. Notably, iron-chelated plants exhibit higher iron content correlating with increased shoot weight and chlorophyll content. The effect of fulvic acids and synthetic chelates might be synergistic, with both providing different advantages that can be complementary in hydroponic solutions. This study highlights the importance of iron management in hydroponics and the way forward for iron fortification techniques.
Speakers
AN

ASMITA NAGILA

Graduate Research Assistant, Texas A&M university
Co-authors
Wednesday September 25, 2024 4:45pm - 4:55pm HST
Coral 2

4:45pm HST

OPB 2 - Treatment with Oryzalin Induces Chromosomal Changes in Salvia coccinea and Salvia splendens
Wednesday September 25, 2024 4:45pm - 5:00pm HST
Salvia coccinea (diploid) and Salvia splendens (tetraploid) and their associated cultivars are widely available, commercially profitable, and environmentally supportive flowering annuals. In recent years, exciting cultivars have been successfully introduced. This investigation explores further development of S. coccinea ‘Summer Jewel Lavender’, S. coccinea ‘Hummingbird Forest Fire’, and S. splendens ‘Mojave Red and White Bicolor’ through treatments by oryzalin for the potential development of novel cultivars. Surflan™ or oryzalin (4-(dipropylamino)-3,5-dinitrobenzenesulfonamide) and the nonionic surfactant SilEnergy™ were applied as a foliar spray for one, two, three, and six days to induce changes in chromosome numbers. Data collected included morphological observations, measurements of foliage and flowers, flower numbers, and ploidy analysis via a CytoFLEX™ flow cytometer. Ploidy changes were achieved in seedlings across all the treatment groups. Novel traits were identified, ranging from smaller overall growth habits and foliage, larger and increased numbers of flowers, and new floral pigmentation while maintaining vigor and potential for container production. Optimization of treatments will be discussed. The findings of this research have practical implications for plant breeders, landscape designers and architects, horticulturists, and environmental researchers as the market continues to demand drought-tolerant, low-growing, long-flowering, and pollinator-attracting plants.
Speakers
JR

John Ruter

University of Georgia
Allan Armitage Endowed Professor of Horticulture and Director, Trial Gardens at UGA
Co-authors
Wednesday September 25, 2024 4:45pm - 5:00pm HST
South Pacific 2

4:45pm HST

WCPM 2/IPR - Sweetpotato (Ipomoea batatas) Variety Tolerance to Different Herbicidal Weed Control Methods
Wednesday September 25, 2024 4:45pm - 5:00pm HST
There are limited herbicides labeled for use in sweetpotato (Ipomoea batatas) production in the United States. Therefore, the registration of additional herbicides with different modes of action (MOA) would provide growers added weed control options to enhanced crop yield and provide a more sustainable sweetpotato (SP) production system. As herbicide-resistant weed populations continue to emerge and become more prevalent, weed control strategies need to include herbicides with different MOAs for the long-term success of (SP) cultivation. This research will identify herbicides, along with rate and application time that could be registered for use in sweetpotato. Herbicide tolerance of four (SP) varieties (Beauregard, Orleans, Dianne, and Covington) were evaluated in a screening study. These varieties were selected to represent sweetpotato production areas across the United States in Arkansas, California, Louisiana, Mississippi, and North Carolina. Herbicides evaluated include fluridone, glyphosate, glufosinate, carfentrazone, saflufenacil, acifluorfen, and others. The study involved the foliar application of herbicide treatments at 1X and 0.5X rates, laid out in a completely randomized design, using a spray chamber onto individual (SP) plants cultivated in 4x4 inch containers within the controlled environment of the Dorman Hall Greenhouse at Mississippi State University. Visual assessments of herbicide-induced injury were conducted at regular intervals of 7, 14, 21, and 28 days after treatment (DAT), accompanied by measurements of vine length in centimeters. Furthermore, dry root and shoot biomass were quantified at 28 DAT to provide a comprehensive assessment of herbicide impacts on (SP) growth and development. Data was analyzed using ANOVA and means separated by Fisher’s protected LSD (α=0.05). Results indicate varying levels of tolerance among the (SP) varieties to specific herbicides and application rates. Noteworthy trends in visual injury, vine length, and biomass measurements highlight the nuanced responses of the cultivars to different herbicide chemistries.
Speakers Co-authors
MS

Mark Shankle

Mississippi State University
Wednesday September 25, 2024 4:45pm - 5:00pm HST
South Pacific 3

4:50pm HST

CHEX/FP - Effect of Planting Date on Strawberry Yield
Wednesday September 25, 2024 4:50pm - 5:00pm HST
Optimizing planting date for strawberry in California production is a sustainable measure to maximize yield and maintain plant health. The goal of this project is to assess the optimal planting date for two predominant cultivars: 'Monterey' and 'Fronteras'. The trial was conducted in field 25 at Cal Poly, San Luis Obispo. The experimental area consisted of 3 beds, each 53.5 ft. long. Standard 64-inch beds with 4 rows of plants per bed and 3 lines of drip tape were used. Beds were planted at two-week intervals: 26 Oct, 9 Nov, 23 Nov 2022. Each bed was planted with four plots of ‘Monterey’ and four plots of ‘Fronteras’ (20 plants/plot). Plug plants were produced at North Carolina State University’s nursery and shipped overnight to Cal Poly and planted in the field the next day. First harvest was 13 Apr 2023 when the first fully red fruit were observed. Fruit were harvested, counted, and weighed twice weekly. The trial was completed 8 Aug 2023 and replicated in the 2024 growing season.
Speakers
SS

Samantha Simard

Cal Poly- San Luis Obispo
Wednesday September 25, 2024 4:50pm - 5:00pm HST
Lehua Suite

4:55pm HST

CE 2 - Effects of Mycorrhiza and Biochar Interactions on Geraniums
Wednesday September 25, 2024 4:55pm - 5:05pm HST
Biochar has long been proposed to be a substitute for peat in soilless mixes for greenhouse growing. Low levels of biochar have been shown to increase disease resistance, increase nutrient supply and uptake, and immobilize phytotoxic substances. Due to its high porosity and pH, biochar has the potential to provide an ideal habitat for mycorrhizal fungi to partner with plant roots. This study examined how various mycorrhiza sources interacted with different biochar rates to effect geraniums (Pelargonium x hortorum L. ‘Maverick Red’). Four different mycorrhizal sources were used in addition to a control containing no mycorrhiza: two commercial sources, MycoBloom and BioAg Vam-Endo, spores extracted from agricultural soils, and spores extracted from prairie soil, with four biochar rates implemented: 0, 15, 30, and 45%. Media with biochar incorporated remained saturated for longer periods after irrigation than pots filled with straight BM-7 peat-media. Prairie soil combined with 15% biochar-BM7 media formed buds and began to flower before all other treatments. Results suggest that biochar and mycorrhiza may pair well to improve potted plant growing.
Speakers
TH

Teal Hendrickson

Oklahoma State University
Co-authors
BD

Bruce Dunn

Oklahoma State University
GW

Gail Wilson

Oklahoma State University
NA
Wednesday September 25, 2024 4:55pm - 5:05pm HST
Coral 2

5:00pm HST

CH/FP - Outcomes of the Western Sustainable Agriculture Research and Education Summit in New Mexico
Wednesday September 25, 2024 5:00pm - 5:10pm HST
The aims of the federal initiative Sustainable Agriculture Research and Education (SARE) are multifaceted: 1) Foster responsible management of the nation's natural resources through the dissemination of location-specific, regional, and sustainable agricultural and ranching techniques, 2) Improve the livelihoods of farmers and ranchers, 3) Safeguard the well-being of individuals involved in food and agricultural systems by reducing reliance on harmful substances, 4) Encourage agricultural variety and resilience, and 5) Assess the local economic, social, and environmental impacts of adopting sustainable agricultural practices. To achieve these goals, SARE offers numerous grant opportunities for research projects, catering to farmers, ranchers, non-governmental organizations, and universities. SARE operates across four regions within the United States. New Mexico is in the Western region (WSARE) which is composed of individual state professional development programs in the area’s 13 states and 4 Pacific Island protectorates. In 2023, the NM WSARE Professional Development Program coordinated a Sustainable Agriculture Summit to better prioritize research and training needs in the state. The event was held in Santa Fe, NM, USA on 30 March, with a total of 58 participants in the full-day event. Among them were 32 agriculture professionals and 26 farmers and ranchers. The event consisted of two main sessions, a panel discussion, followed by an open forum. The panel was comprised of past Western SARE grant recipients and individuals who had submitted proposals, they provided overviews of their projects. Following the panel, summit participants engaged in a brainstorming session to identify critical sustainable agriculture project needs for producers in NM, focusing on research and training needs not previously emphasized in past funding. The priority areas identified by the participants were, in order of importance, 1) Irrigation/water use efficiency, 2) Farm economics, direct markets, and direct sales, 3) Non-traditional production, 4) Pest management, 5) Labor aids and technology adaptation, and 6) Generational transfer of farms and ranches. Each of these priorities was clearly outlined, and potential projects were identified accordingly. The outcomes of this summit were communicated to WSARE, the NM Department of Agriculture, and other funding agencies, offering valuable feedback to guide future proposals and funding initiatives in NM.
Speakers
ME

Mariela Estrada

New Mexico State University
Co-authors
IJ

Israel Joukhadar

New Mexico State University
Wednesday September 25, 2024 5:00pm - 5:10pm HST
Lehua Suite

5:00pm HST

WCPM 2/IPR - Soil Steaming: A Sustainable Weed Management Strategy in Sweetpotato
Wednesday September 25, 2024 5:00pm - 5:15pm HST
The Sweetpotato (Ipomoea batatas (L.) Lam.) has flexible uses as food, feed, and industrial product usage. There are over 27,000 acres across one-hundred and fifty farms in Mississippi and the state also ranks second and third in the nation in acreage and production, respectively. It is paramount for all farmers to suppress weed species, enhance biodiversity, improve soil health, and minimize pests and diseases in plants. In sweet potatoes, there is a significant problem with weeds interfering with yields, reducing crop yield by up to 80%. A chemical approach is usually the most popular utilization, but it can lead to disadvantages with crop quality, intolerance, and, in worst-case scenarios, environmental toxicity. To overcome limited weed control options and preserve or improve sweet potato quality and yield for Mississippi growers, there is a great need to find a supplemental weed control strategy. One solution is the utilization of soil steaming, an alternative method that is environmentally friendly and organically favored. This study aimed to assess the most effective soil steaming depth and duration for controlling a troublesome weed in sweetpotatoes, yellow nutsedge (Cyperus esculentus (L.)). This study is conducted in split plot designs with the soil steaming plots as the main plots in field and greenhouse situations. This was to test different durations of times and depths in the soil for both areas. Depths of 2, 5, and 8 inches, were used. Times of 0, 1, 5, 20, 45 minutes, were used. Maximum temperatures reached were 82 ºC. The germination count was recorded at 21 DAT. The highest weed coverage (55%) was observed in 0 minutes duration. The second highest (30%) was observed at 5 minutes. The least amount of coverage (20%) was observed at 20 minutes. The adoption of soil steaming would be beneficial in sustainable suppression of yellow nutsedge in organic sweetpotato farms. Keywords: soil steaming, weed suppression, sweetpotato, sustainability, organic
Speakers
AR

Alaina Richardson

Mississippi State Univeristy
Co-authors
AM

Alyssa Miller

Mississippi State Univeristy
JA

Josiane Argenta

Mississippi State Univeristy
NA
ML

Mackenzie Lee

Mississippi State Univeristy
NA
NM

Ncomiwe Maphalala

Mississippi State Univeristy
NA
SB

Shaun Broderick

Mississippi State Univeristy
TP

TeMing Paul Tseng

Mississippi State Univeristy
NA
Wednesday September 25, 2024 5:00pm - 5:15pm HST
South Pacific 3

5:00pm HST

Executive committee meeting of the American Pomological Society
Wednesday September 25, 2024 5:00pm - 7:00pm HST
Moderator
avatar for Ksenija Gasic

Ksenija Gasic

Clemson University
Wednesday September 25, 2024 5:00pm - 7:00pm HST
Sea Pearl 3

5:05pm HST

CE 2 - Exploring Different Nutrient Solution Quantities to Optimize Quantity and Quality in Hydroponic Production
Wednesday September 25, 2024 5:05pm - 5:15pm HST
Nutrient solutions play a crucial role in determining crop yield and quality, with optimized quantities offering sustainability benefits. However, there is a lack of comprehensive research regarding the optimal nutrient application quantity for various leafy green vegetables in recirculating hydroponic cultivation. To address this research gap, we proposed a project on different nutrient application quantities using the nutrient film technique (NFT) hydroponic system in a greenhouse with three replications during the fall (air temp: 24.22°C, RH: 31.2%), winter (air temp: 15.5 °C, RH: 73.3%) and early spring (air temp: 13.7 °C, RH: 72.4% ). The project focused on exploring different nutrient solution quantities of Low (76 liters), Medium (114 liters), and High (151 liters) nutrient regimens for six different leafy green vegetable species and cultivars common in Kansas including red butter lettuce (Lectuca sativa), green butter lettuce (Lectuca sativa), arugula (Eruca sativa), kale (Brassica oleracea), red malabar spinach (Basella alba), and basil (Ocimum basilicum). Our results showed that green butter lettuce and basil remained unaffected by the treatments throughout the study. Additionally, plant height, leaf count, and SPAD value for all species remained consistent across treatments and seasons. However, during the fall, the shoot fresh weight of red butter lettuce and kale increased by 7.11% and 21.1%, respectively, in the high-nutrient regimen. Moreover, the dry shoot weight of kale increased by 18.7% in the high-nutrient regimen, while the dry shoot weight of the red malabar spinach increased by 10.3% in the low-nutrient regimen. In contrast, during winter, the shoot fresh weight of red butter lettuce increased by 18.9% and 25.0%, respectively, in medium nutrient regimens compared to low and high nutrient regimens. Similarly, the shoot fresh weight of red malabar spinach increased by 15.3% and 25.0%, respectively, in low-nutrient regimens compared to medium and high-nutrient regimens. During early spring, the shoot fresh weight of red butter lettuce increased by 17.9-18.0% and that of arugula increased by 17.8% in the high-nutrient regimen, compared to low and medium nutrient regimens. In summary, the high-nutrient regimen benefited red butter lettuce and kale in fall and arugula in early spring. Conversely, during winter, the medium nutrient regimen benefited red butter lettuce, while the low nutrient regimen benefited red malabar spinach. The results from this experiment identified the optimal nutrient application quantity which helps to reduce nutrient waste for vital leafy vegetables in Kansas for different seasons and offers valuable production guidelines for local growers.
Speakers
PS

Puja Subedi

Kansas State University
I am a graduate research assistant working at the Kansas University Olathe, 22201 W Innovation Dr, Olathe, KS 66061. My major is urban food system under the department of horticulture and natural resources. Currently, I am working in the hydroponics research project.
Co-authors
TY

Teng Yang

Kansas State University
Wednesday September 25, 2024 5:05pm - 5:15pm HST
Coral 2

5:15pm HST

CE 2 - The Effect of Climate Change on Plants: A Case Study with Wheat
Wednesday September 25, 2024 5:15pm - 5:25pm HST
Anthropogenic climate change (ACC) will have considerable effects on plants, though the extent to which these effects are positive or negative has been controversial. For this poster, a fully factorial experiment combining water and temperature over broad ranges (10-90% soil water content under 16°C-40°C) was carried out to address three shortcomings that might help explain the contrasting effects of climate change on plants: testing only one climate variable (e.g., only water or only temperature), failure to account for nonlinear responses to climatic variables, and studying a limited number of response variables. The experiment utilized wheat as the model species and found that most dependent variables related to grain production showed the highest performance under 23-33°C and low water (
Speakers
KW

Kira Webster

University of Hawaii at Manoa
Wednesday September 25, 2024 5:15pm - 5:25pm HST
Coral 2

5:15pm HST

WCPM 2/IPR - Assessment of Various Carbon Sources for Anaerobic Soil Disinfestation to Manage Weeds in Organic Sweetpotato
Wednesday September 25, 2024 5:15pm - 5:30pm HST
Yellow nutsedge (Cyperus esculentus L.) management in organic plasticulture systems is challenging as it reproduces both by seeds and tubers. Yellow nutsedge has a strong midrib and sharp leaf tip which allows it to puncture plastic mulch and creates favorable conditions for other weeds to grow, compete for resources with crop plants, and decrease crop yield. Lack of available herbicide options in specialty crops make weed management more challenging. Anaerobic soil disinfestation (ASD) is a technique that has shown potential to manage weeds in organic production systems. ASD is facilitated by incorporating carbon sources into the soil, tarping the soil with plastic mulch, and irrigating to the soil saturation. A field study was conducted at Clemson University’s Coastal Research and Education Center, Charleston, South Carolina, to evaluate the impact of various carbon sources in ASD on weed management in organic sweetpotato. This treatment structure for this study consisted of a factorial with four carbon source treatments (cotton seed meal, chicken manure molasses, brassica waste, and non-amended control) and four sweetpotato cultivars (Bayyou Belle, Muraski, Monaco, and USDA 18-040). These sweetpotato cultivars have two different growth habits, either bunch type (USDA 18-040 and Monaco) or spreading type (Bayyou Belle and Muraski). The primary purpose of using different plant architecture is to evaluate the impact of the sweetpotato vine growth habit on weed emergence. Experimental plots receiving chicken manure molasses and cotton seed meal as carbon source resulted in the greatest cumulative anaerobic conditions (
Speakers
SS

Simardeep Singh

Clemson University
Co-authors
Wednesday September 25, 2024 5:15pm - 5:30pm HST
South Pacific 3

5:25pm HST

CE 2 - How Does Supplementing Dissolved Oxygen Impact Hydroponic Strawberry Production?
Wednesday September 25, 2024 5:25pm - 5:35pm HST
Oxygen is crucial for the growth and nutrient uptake of plant roots, especially in crops like strawberries that demand high levels of oxygen in their root zones. However, in hydroponic systems, the nutrient solution is often inadequately oxygenated. In this study, we examined the effects of supplementing dissolved oxygen (DO) into the nutrient solution on the growth of strawberry plants. Inside an indoor vertical farm, bare-root plants of strawberry ‘Albion’ and ‘Eversweet’ were grown using deep water culture hydroponics under a controlled environment of 23 °C air temperature and an 18-h photoperiod, with an extended photosynthetic photon flux density of 350 µmol∙m –2 ∙s –1 . The DO concentration of the nutrient solution was maintained at control levels (no adjustment) or supplemented using an air pump or an oxygen concentrator. The average DO concentrations in the control condition was 70%, while supplementing the nutrient solution with an air pump or an oxygen concentrator increased the average DO concentration to 85% and 100%, respectively. Supplementing with DO had minimal to no effect on the days to root of strawberry bare root plants in both cultivars. Four weeks after the DO treatments, root length, crown diameter, leaf area, and fresh mass of shoot and root were also similar in both cultivars regardless of DO concentration. The effects of supplementing DO on flowering and fruit production will also be presented.
Speakers
JR

Jonathan Ries

Arizona State University
Co-authors
YP

Yujin Park

Arizona State University
Wednesday September 25, 2024 5:25pm - 5:35pm HST
Coral 2

5:30pm HST

WCPM 2/IPR - Evaluation of saturated steam with boiling water to control Guinea grass (Megathyrsus maximus) in riparian landscapes in Hawaii.
Wednesday September 25, 2024 5:30pm - 5:45pm HST
Boiling water and steam have been effectively used as a non-chemical means to control weeds in croplands and urban areas. In Hawaii, it is a relatively new technology with limited trials done on local conditions and weeds. Guinea grass (Megathyrsus maximus) is a noxious weed that invades landscapes and agricultural fields in Hawaii and throughout the world. While it is typically controlled using herbicide sprays, this may be restricted if the guinea grass being controlled is located in riparian areas. In this study, we evaluated the efficacy of saturated steam with boiling water in controlling mature clumps of guinea grass growing along a streambank. Guinea grass bunches were divided into small (less than 15.2 cm) and large clumps (15.2 to 30.5 cm) and then cut 5 to 15 cm from the ground. Cut clumps were either not treated (control) or treated with saturated steam and boiling water for 1 minute using a 15cm long spike injector inserted into different points of the crown. Percent green color and number of resprouts were collected 7, 14, and 21 days after application. Dry biomass was collected 22 days after application. Results indicate that saturated steam with boiling water was effective in controlling guinea grass clumps. Small clumps were completely controlled (no resprouts and new biomass) while large clumps had significantly reduced the number of resprouts and reduced production of new biomass. Saturated steam with boiling water offers a non-chemical means to control guinea grass in riparian areas in Hawaii.
Speakers
HL

Hannah Lutgen

Extension Faculty, CTAHR
Co-authors
OB

Orville Baldos

University of Hawaii at Manoa
RG

Rosemary Gutierrez Coarite

University of Hawaii at Manoa
Wednesday September 25, 2024 5:30pm - 5:45pm HST
South Pacific 3

5:35pm HST

CE 2 - Exploring Different EC Levels to Optimize Quantity and Quality in Hydroponic Production
Wednesday September 25, 2024 5:35pm - 5:45pm HST
Efficient nutrient management is the key to successful hydroponic production. However, there is a lack of comprehensive research regarding the optimal electrical conductivity (EC) levels for various leafy green vegetables in recirculating hydroponic cultivation. To address this research gap, we experimented with different EC levels using the nutrient film technique (NFT) hydroponic system in a greenhouse with three replications during the fall (air temp: 24.22°C, RH: 31.2%) winter (air temp: 15.5 °C, RH: 73.3%) and early spring (air temp: 13.7 °C, RH: 72.4%). The experiment was conducted using three different EC levels (1.2, 1.8, and 2.4 mS/cm) for six different leafy green vegetables kale (Brassica oleracea) ‘Winter bor F1’ and ‘Toscano’, swiss chard (Beta vulgaris), basil (Ocimum basilicum) ‘Prospera® Compact DMR (PL4)’ and ‘large leaf’ and red malabar spinach (Basella alba). Our results showed that, during the fall, the shoot fresh weight of the ‘Winter bor F1’ increased by 13.1 % in EC 2.4 compared to EC 1.2 and that of Swiss chard increased by 8.3-20.6% in EC 2.4 compared to EC 1.2 and 1.8 while that of ‘Prospera® Compact DMR (PL4)’ basil increased by 13.1-13.9 % in EC 1.8 compared to EC 1.2 and 2.4. In contrast during the winter, the shoot fresh weight of ‘Toscano’ kale, ‘Winter bor F1’ kale, and ‘large leaf’ basil increased by 11.2-17.8%, 18.9-20.8%, and 13.2-14.7%, respectively in EC 2.4 compared to EC 1.2 and 1.8, while that of ‘Prospera® Compact DMR (PL4)’ basil increased by 19.2 % in EC 1.2 compared to the EC 2.4. However, during the early spring, only the shoot fresh weight of ‘Winter bor F1’ kale in EC 1.8 was increased by 10.0 % compared to EC 1.2, while the plant height and fresh shoot weight of large leaf basil was increased slightly by 3.1-5.6% in EC 2.4 compared to EC 1.2. In summary, this experience suggested that ’Winter bor F1’ kale performed best in EC 2.4 during the fall and winter seasons but grew best in EC 1.8 during the early spring. In addition, the 2.4 mS/cm proved the optimal EC level for Swiss chard during the fall, ‘Toscano’ kale during the winter, and ‘large leaf’ basil during the spring. The results from this experiment identify optimal EC levels of vital leafy vegetables in Kansas for different seasons, aiding Kansas growers in reducing nutrient waste and enhancing leafy vegetable production.
Speakers
PS

Puja Subedi

Kansas State University
I am a graduate research assistant working at the Kansas University Olathe, 22201 W Innovation Dr, Olathe, KS 66061. My major is urban food system under the department of horticulture and natural resources. Currently, I am working in the hydroponics research project.
Co-authors
TY

Teng Yang

Kansas State University
Wednesday September 25, 2024 5:35pm - 5:45pm HST
Coral 2

6:00pm HST

Graduate Student Poster Competition
Wednesday September 25, 2024 6:00pm - 7:00pm HST
This competition is open to graduate students that have a poster presentation scheduled during the ASHS conference AND have also signed up to participate in this competition (Note: This is separate of the assigned time to present your abstract during the conference program).

Please note that if you do not also present your poster during the regularly scheduled Poster session, you will be disqualified from the Poster Competition.

Competition participants will be assigned to a room to present for the competition (this information will be emailed to you the week prior to the conference). You will be responsible for bringing your poster on a thumb drive to your assigned room in order to participate.

Wednesday September 25, 2024 6:00pm - 7:00pm HST
Coral 1

6:00pm HST

Graduate Student Poster Competition
Wednesday September 25, 2024 6:00pm - 7:00pm HST
This competition is open to graduate students that have a poster presentation scheduled during the ASHS conference AND have also signed up to participate in this competition (Note: This is separate of the assigned time to present your abstract during the conference program).

Please note that if you do not also present your poster during the regularly scheduled Poster session, you will be disqualified from the Poster Competition.

Competition participants will be assigned to a room to present for the competition (this information will be emailed to you the week prior to the conference). You will be responsible for bringing your poster on a thumb drive to your assigned room in order to participate.

Wednesday September 25, 2024 6:00pm - 7:00pm HST
Kahili

6:00pm HST

Graduate Student Poster Competition
Wednesday September 25, 2024 6:00pm - 7:00pm HST
This competition is open to graduate students that have a poster presentation scheduled during the ASHS conference AND have also signed up to participate in this competition (Note: This is separate of the assigned time to present your abstract during the conference program).

Please note that if you do not also present your poster during the regularly scheduled Poster session, you will be disqualified from the Poster Competition.

Competition participants will be assigned to a room to present for the competition (this information will be emailed to you the week prior to the conference). You will be responsible for bringing your poster on a thumb drive to your assigned room in order to participate.


Wednesday September 25, 2024 6:00pm - 7:00pm HST
Coral 2
 
Thursday, September 26
 

7:00am HST

Speaker Ready Room - Thursday
Thursday September 26, 2024 7:00am - 6:00pm HST
Thursday September 26, 2024 7:00am - 6:00pm HST
Sea Pearl 1-2

7:30am HST

Industry Division Breakfast
Thursday September 26, 2024 7:30am - 9:30am HST
Advance ticket purchase is required.
Featured Speaker - Becky Ryan, Maui Product Development Center Lead, Bayer U.S. Crop Science
Moderator
JC

Javier Castillon

ASHS Industry Division VP
Speakers
BR

Becky Ryan

Maui Product Development Center Lead, Bayer U.S. - Crop Science
Thursday September 26, 2024 7:30am - 9:30am HST
Hibiscus 1

7:30am HST

Registration Open - Thursday
Thursday September 26, 2024 7:30am - 6:00pm HST
Thursday September 26, 2024 7:30am - 6:00pm HST
Coral Lounge

7:59am HST

Viticulture and Small Fruits 3 (VSF 3)
Thursday September 26, 2024 7:59am - 9:15am HST
Using Biochar As a Soil Amendment in Blueberry Production - Zilfina Rubio
Effects of Aged Pine Bark Amendments on Container-Grown Southern Highbush Blueberry Growth and Substrate Properties - Brandan Shur
Ground Covers Shape Canopy Microclimate And Fruit Quality Components In A Blueberry Orchard - Josh VanderWeide
Enhancing Blueberry Production with Photo-Selective Devices - Amit Godara
Modeling Production Curves of Southern Highbush Blueberry for Improved Productivity and Efficient Harvestability - J. Martin Zapien-Macias

Moderator
ZR

Zilfina Rubio

University of Georgia
Thursday September 26, 2024 7:59am - 9:15am HST
South Pacific 2

7:59am HST

Ecological Physiology 2 (EcoPhys 2)
Thursday September 26, 2024 7:59am - 9:30am HST
Exploring the Effects of Irrigation Water Salinity on Physiology and Growth of Papaya (Carica papaya) in a Calcareous Soil - Ana Vargas
Physiological, Biochemical, and Morphological Responses of Achachairu (Garcinia humilis) to Soil Salinity, Flooding, and Exogenous Applications of 24-epibrassinolide - Federico Sanchez
Plant Physiological and Root Anatomical Responses of Two Novel Olive Cultivars (‘Oliana’ and ‘Lecciana’) Under Salinity - Khalid Hussain
Continuous monitoring of tree water status using microtensiometers for irrigation management in olive - Paula Guzman-Delgado
The Carbon Cost of Phosphorus Deficiency in Southern Highbush Blueberry - Marlon Retana-Cordero
Intra- and Inter-Annual Changes in Soil Health with Native Plant Monocultures - Bret Lang

Moderator
PG

Paula Guzman-Delgado

University of California Davis
Thursday September 26, 2024 7:59am - 9:30am HST
Lehua Suite

7:59am HST

Ornamental Plant Breeding 1 (OPB 1)
Thursday September 26, 2024 7:59am - 9:30am HST
The Boons of Breeding at a Botanic Garden - Justin Lombardoni
Mutagenesis of Hardy Hibiscus Using Ethyl Methanesulfonate - Greta Gallina
Genetic Sterilization of Four Invasive Ornamental Plant Species to Reduce Their Invasive Potential: Progress and Prospects - Zhanao Deng
Inheritance and Genetics of Ornamental Traits in Pomegranates - Alexander Schaller
Induction and Characterization of Mutations Related to Dwarf Habit in Hardy Hibiscus (Muenchhusia section) - Conner Austin
Compatibility of Cross-hybridizing Lagerstroemia taxa - Yongjun Yue


Moderator
JL

Justin Lombardoni

Chicago Botanic Garden
Thursday September 26, 2024 7:59am - 9:30am HST
South Pacific 4

7:59am HST

Floriculture 2 (FLOR 2)
Thursday September 26, 2024 7:59am - 9:45am HST
Sustainability Beliefs and Practices in the United States Floriculture Industry - Amanda Solliday
Hydroponic, Soilless, and Field Produced Cut Flower Bouquets in the Northeast US. - Jacob Schwab
Influence of Varietal Differences and Cutting Lengths on the Rooting Abilities and Growth Performances of Bougainvillea - Olatunde Olosunde
Influence of UV-A Night Interruption Lighting on the Growth of Potted Basil Plants - Seth Benjamin
Evaluating Nighttime Application of Low Intensity LED Light Qualities to Suppress Downy Mildew Caused by Plasmopara obducens on Greenhouse Grown Impatiens - River Dean
Supplemental Day-Extension Lighting Influences Rooted Cutting Growth and Quality of Finished Annual Bedding Plants - Lauren Seltsam
Daily Light Integral Influences Adventitious Rooting of Achillea Cuttings - Garrett Owen
Moderator
LS

Lauren Seltsam

The Ohio Sate University,
Thursday September 26, 2024 7:59am - 9:45am HST
South Pacific 3

7:59am HST

Growth Chambers and Controlled Environments 4 (CE 4)
Thursday September 26, 2024 7:59am - 9:45am HST
Night Light Pollution Delays Flowering in Soybean and Cannabis - Madigan Eckels
Pre-breeding Leafy Green Watercress (Nasturtium officinale; Brassicaceae) In an Indoor Vertical Farm: A Discovery Trial - Yufei Qian
Precise Moisture Control Promotes Optimal, Fast, and Uniform Spinach Seed Germination - Shem Msabila
Planting Density on the Growth and Production of Select Fruiting Crops in Aquaponic Systems - Teal Hendrickson
Global Sensitivity Analysis and Validation of the Modified Energy Cascade Crop Model for Controlled Environment Agriculture - Donald Coon
Planting Density and the Growth of Kale and Cilantro in Year-round Aquaponics - Teal Hendrickson
The Physiological Responses of Citrus Tree Roots to Soil Acidification - Duplicate Sambani
Towards Sustainable Controlled Environment Agriculture Systems: Developing An Intelligent Decision-Making Tool For Improved Resource Use Efficiency - Eshwar Ravishankar


Speakers
avatar for Madigan Eckels

Madigan Eckels

Utah State University
NA
Thursday September 26, 2024 7:59am - 9:45am HST
Coral 1

7:59am HST

Teaching Methods 2 (TCHG 2)
Thursday September 26, 2024 7:59am - 9:45am HST
Seed Your Future Horticultural Salary Survey - John DoleHorticultural and Plant Science Undergraduate Enrollment Summary Based on Food and Agricultural Education Information System (FAEIS) Data - John DoleCreating a Sustainable Vegetable Production Registered Apprenticeship Program: A Review of Curriculum Development and Lessons Learned - Angel Cruz
Impact of Greenhouse Training Online Program - Nelda Raquel Hernandez Martinez
Invasive Species Education in Florida: Insights from a Yearlong Webinar Pilot Program - Morgan Pinkerton
Closing the Gap: Developing Greater Awareness of Horticulture Careers in Controlled Environment Agriculture in Secondary Schools - Melanie Yelton
Educational Initiatives in Cannabis: Curriculum Development for a Growing Workforce - Yousoon Baek


Moderator
YB

Yousoon Baek

Cornell University
Thursday September 26, 2024 7:59am - 9:45am HST
Kahili

7:59am HST

Vegetable Crops Management 4 (VCM 4)
Thursday September 26, 2024 7:59am - 9:45am HST
Watermelon Rootstock Variety Trial to Understand the Impacts of Grafting on Watermelon Yield and Fruit Quality - Fayrouz Buojaylah
Effect of Biofungicides Containing Trichoderma and Grafting on Watermelon Productivity and Plant Health - Fayrouz Buojaylah
Canary Melons Cultigen Yield and Quality Evaluations in North Carolina, 2023 - Jonathan Schultheis
Watermelon Cultigen Yield Response to Fusarium oxysporum f. sp. niveum Incidence in North and South Carolina, USA - Stuart Michel
Effect of Biostimulants on Field Grown Watermelon (Citrullus lanatus) under Deficit Irrigation and Fertility. - Evan Christensen
Development of the winter artichoke production system in a subtropical climate - Shinsuke Agehara
Globe Artichokes - Variety Trials for Florida Production and Marketing Evaluations - Evelyn Fletcher

Moderator
FB

Fayrouz Buojaylah

University ofr California, Cooperative Extension Stanislaus County
Thursday September 26, 2024 7:59am - 9:45am HST
Coral 2

7:59am HST

Ornamentals/Landscape and Turf 2 (O/LT 2)
Thursday September 26, 2024 7:59am - 10:00am HST
The Climate Ready Landscape Plants Project. Testing Plants For Drought Tolerance Across The Western U.S. - Lorence Oki
Performance of landscape shrubs under three irrigation levels in Arizona - Ursula Schuch
Performance of Landscape Plants in California’s Central Valley Under Three Levels of Deficit Irrigation - Jared Sisneroz
Field Trials of Landscape Plants under Reduced Irrigation Frequency - Zirui Wang
Understanding Hernando County Residents' Perspectives on Fertilizer Use and Regulations - William Lester
Using Different Ratios of Blue and Red Light to Induce Drought Tolerance Morphology in Zinnia - Anju Chaudhary
Techniques to Improve Growth, Heat, and Drought Tolerance in Container Grown Trees - Drew Zwart
Using Marketing Initiatives to Promote the UF/IFAS Extension Florida-Friendly Landscaping Program - Tom Wichman
Moderator
JS

Jared Sisneroz

UC Davis
Mr. Sisneroz is the project manager of the UC Landscape Plant Irrigation Trials (UCLPIT) and the ‘Climate Ready Landscape Plants’ programs. He specializes in landscape plant water-use efficiency research and water resource management.
Thursday September 26, 2024 7:59am - 10:00am HST
South Pacific 1

7:59am HST

Postharvest 3 (PH 3)
Thursday September 26, 2024 7:59am - 10:15am HST
Assessing Apple Cultivar Responses to Low Oxygen Limit Determination Using Chlorophyll Fluorescence and Respiratory Quotient - Hnin Phyu Lwin
Understanding how physiological maturity and storage regime affect skin greasiness on WA 38 apples - Carolina Torres
Chlorophyll to Carotenoid Ratio Measured Nondestructively Correlates with Peel Pigment Content and Canopy Attachment Position of ‘Granny Smith’ Apples - Manoella Mendoza
Early Spectral Differences on Scald Disorders in ‘Granny Smith’ Apples - Rene Mongollon
Apple Ripening After DCA Storage: Assessing The Risk Of Flavor Loss - Randolph Beaudry
The Impact Of Hot Water Treatment On Organic Apple Quality With Different Storage Systems - Sadat Amankona
Fungicides and Scald Inhibitor Diphenylamine Shift Microbiomes of ‘Fuji’ Apples Through Short Term Cold and Room Temperature Storage - Connor Lane
Pyrus communis: A Model for Studying Climacteric Ripening and Senescence - Amit Dhingra
Characterization of Postharvest Rots and the Susceptibility to Decay of 38 European Pear Genotypes during Cold Storage. - Tamara Collum
Moderator
avatar for Manoella Mendoza

Manoella Mendoza

WA State University
Thursday September 26, 2024 7:59am - 10:15am HST
Nautilus 1

8:00am HST

CE 4 - Night Light Pollution Delays Flowering in Soybean and Cannabis
Thursday September 26, 2024 8:00am - 8:15am HST
As urban centers encroach on agricultural land, it is increasingly important to study the effects of light pollution on sensitive short day flowering crops such as Glycine max (soybean) and Cannabis sativa. Common responses to light pollution include delayed flower initiation and development, and Cannabis growers additionally speculate a myriad of other detriments as a result of light pollution. We conducted a series of studies with three soybean and ten Cannabis cultivars to elucidate responses to light pollution. Plant were grown under full-night light pollution ranging from 0 to 150 nanomols m-2 s-1 of cool white light or 0 to 40 nmols m-2 s-1 of red light at 660 nm. We found that continuous light pollution as low as 10 nmol m-2 s-1 from cool white LEDs delayed inflorescence initiation and development of the most sensitive Cannabis cultivars, while red light pollution as low as 5 nmol m-2 s-1 caused similar effects. In cultivars that did not experience a delay in inflorescence initiation, other plant characteristics including height and inflorescence development rate were negatively impacted. In soybean, flower delay in response to light pollution varied by cultivar but was reduced or absent in more modern lines, indicating that breeding may have selected against light sensitivity. Future growers must consider tolerance to light pollution during cultivar selection in order to avoid the detrimental impacts to short day crops.
Speakers
avatar for Madigan Eckels

Madigan Eckels

Utah State University
NA
Co-authors
BB

Bruce Bugbee

Utah State University
NA
MW

Mitch Westmoreland

Utah State University
NA
PK

Paul Kusuma

Utah State University
NA
Thursday September 26, 2024 8:00am - 8:15am HST
Coral 1

8:00am HST

EcoPhys 2 - Exploring the Effects of Irrigation Water Salinity on Physiology and Growth of Papaya (Carica papaya) in a Calcareous S
Thursday September 26, 2024 8:00am - 8:15am HST
In many tropical fruit production areas, including southern Florida, a rise in ocean levels resulting from climate change is anticipated to lead to greater inland intrusion of saltwater, thereby increasing salinity of the soil and/or irrigation water. Thus, knowing the salinity level of the soil or irrigation water that negatively impacts tropical fruit crops, including papaya, is important to alleviate salinity-induced damage to these crops. A study was conducted to evaluate physiological and growth responses of two papaya (Carica papaya L.) cultivars grown commercially in Florida (‘Red Lady’ and ‘Exp15’) to different irrigation salinity levels. Papaya seedlings were transplanted into 11.4-liter pots with Krome very gravelly loam soil; a calcareous soil collected from the papaya production area in south Florida. Each plant was manually irrigated three times per week with 1 liter of deionized water containing different concentrations artificial sea salt (Instant Ocean®) to obtain 4 salinity levels based on electrical conductivity (EC) of the irrigation water i.e., 0 (control), 3, 6, and 9 dS/m. Plants performance under different salinity levels was evaluated by determining net CO2 assimilation (A), stomatal conductance (gs), transpiration (E), the leaf chlorophyll index (LCI), and the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) on a weekly basis throughout the study. Normalized difference vegetation Index (NDVI) values derived from multispectral images were also collected weekly. After seven weeks, plants were harvested and leaf relative water content (RWC), leaf water potential, leaf area, and leaf, stem, and root dry weights were determined for all plants. Five weeks after treatments were initiated, for both cultivars, plants in the 6 and 9 dS/m treatments had lower A, E, gs, LCI, and Fv/Fm than plants in the other treatments. At the end of the experiment, plants in the 3, 6, and 9 dS/m treatments had significantly lower A, E, gs, LCI, Fv/Fm, leaf water potential, leaf area, and leaf, stem, and root dry weights than plants in the other treatments. Also at the end of the experiment, ‘Exp15’ plants in the 9 dS/m treatment had lower NDVI values than plants in the other treatments, whereas there was no difference in NDVI among treatments for ‘Red Lady’. There was no significant effect of salinity treatment on RWC. The findings suggest that 'Red Lady' and ‘Exp15’ papaya plants are unable to withstand salinity levels of 3 dS/m or higher in the calcareous agricultural soil of southern Florida.
Speakers
AV

Ana Vargas

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
BS

Bruce Schaffer

University of Florida
DH

Dong Hyeon Kim

University of Florida
NA
MS

Muhammad Shahid

University of Florida
NA
YG

Young Gu Her

University of Florida
NA
YL

Yuncong Li

University of Florida
NA
Thursday September 26, 2024 8:00am - 8:15am HST
Lehua Suite

8:00am HST

FLOR 2 - Sustainability Beliefs and Practices in the United States Floriculture Industry
Thursday September 26, 2024 8:00am - 8:15am HST
Today’s environmental and social concerns – including climate change and economic inequality – push sustainability to the forefront of many business strategies, from tech companies to grocery retailers to flower farmers. To better understand the scope and limitations of sustainable practices among flower growers, wholesalers, retail florists, and floral suppliers, the research team administered an industry-wide survey. Sections of the survey delve into aspects of floriculture businesses throughout the United States, including scale of operations, current sustainability measures, motivations driving sustainability activities, and barriers preventing sustainable practices. The results indicate strong personal motivations for sustainability measures within floriculture, yet respondents perceived a lack of financial or regulatory incentives to implement such practices. A subset of results for growers are compared to a 2008 survey to assess changes in sustainability practices within domestic flower production over time. Regional variances in perceived access to resources and implementation of sustainability practices will also be discussed. Our study aims to identify key areas where progress has been made or can be made in the industry, including educational efforts and incentives to address the perception of risk when implementing sustainability practices. A subset of results for growers are compared to a 2008 survey to assess changes in sustainability practices over time within domestic flower production. Our study aims to identify key areas where progress has been made or can be made in the industry, including educational efforts to address the perception of risk when implementing sustainability practices and communicating benefits to consumers.
Speakers
avatar for Amanda Solliday

Amanda Solliday

PhD student, North Carolina State University
Hi, I'm a PhD student at NC State University conducting sustainability and climate research in cut flowers.
Co-authors
MK

Melinda Knuth

North Carolina State University
Thursday September 26, 2024 8:00am - 8:15am HST
South Pacific 3

8:00am HST

O/LT 2 - The Climate Ready Landscape Plants Project. Testing Plants For Drought Tolerance Across The Western U.S.
Thursday September 26, 2024 8:00am - 8:15am HST
The Climate Ready Landscape Plants project evaluates the performance of plants exposed to three different deficit irrigation treatments in six climate zones. The experimental fields are completely replicated at all of the sites with plants spaced in a 2m x 2m layout, 8 replicates per treatment, up to 15 taxa tested per site, and irrigation based on reference evapotranspiration (ETo) with treatments of 20%, 50%, and 80% of ETo. Irrigation applications consist of a fixed volume of water depending on soil plant available water as determined by the US Geological Survey maps accessed via SoilWeb. The interval between irrigations was determined by accumulating daily ETo modified by the treatment factor. Irrigation occurred when the trigger value was attained. Plants were installed in the fall and irrigated with sufficient water for establishment during the first irrigation season and treatments were imposed during the second irrigation season. Monthly during treatment, 6 qualitative assessments of each plant were conducted and measurements in three directions were recorded to calculate a Plant Growth Index until the end of the treatment period that typically concluded in October. A substantial effort was made to ensure site-to-site consistency of the qualitative assessments by developing a ratings rubric and conducting frequent site visits with project management to “calibrate” site staff conducting the evaluations. Open House Field Days were conducted during the treatment season to which horticultural professionals and Master Gardeners were invited to evaluate the plants. This provided additional data and introduced the plants to potential users. This project started in 2004 as a graduate student research project, was expanded periodically at UC Davis, and then duplicated in 2017 at the UC South Coast Research and Extension Center in Irvine, CA as the University of California Landscape Plants Irrigation Trials™ (UCLPIT) project. With an award from the USDA Specialty Crops Multistate Program in 2019, the project was expanded to the University of Washington, Oregon State University, Utah State University, and the University of Arizona which facilitates the comparison of plant performance in response to deficit irrigation treatments across the western region of the U.S. The data collected leads to recommendations for irrigating those plants that are used by homeowners and landscape irrigation managers and assists landscape designers and architects designing landscapes that are water conserving and complying with California's landscape water conservation regulation, the Model Water Efficient Landscape Ordinance (MWELO).
Speakers
LO

Lorence Oki

University Of California, Davis
Co-authors
DH

Darren haver

University of California
NA
KR

Karrie Reid

University of California
NA
LN

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
RC

Ryan Contreras

Oregon State University
SK

Soohyung Kim

University of Washington
US

Ursula Schuch

University of Arizona
YS

Youping Sun

Utah State University
Thursday September 26, 2024 8:00am - 8:15am HST
South Pacific 1

8:00am HST

OPB 1 - The Boons of Breeding at a Botanic Garden
Thursday September 26, 2024 8:00am - 8:15am HST
While many institutions have staff that dabble in plant breeding, the Chicago Botanic Garden is one of the only gardens to administer a breeding program dedicated to introducing ornamental perennials. A botanic garden possesses a wealth of resources not available to hobbyist breeders and other companies, providing key advantages that aid in cultivar development. Among these resources are staff members that support plant breeding with different fields of expertise, such as horticulture, production, propagation, and landscape design. Other resources include well-maintained breeding beds and greenhouses for crossing plants and growing progenies as well as a plant exploration program that conducts both national and global plant collection trips. Various lab facilities are available through the science department, including equipment and staff that can help with seed cleaning and banking, pollen banking, flow cytometry, and more. Because the Chicago Botanic Garden and its plant introduction program Chicagoland Grows® are non-profits, there is more freedom to work on lesser known genera. This contrasts with traditional industry breeding, which often focuses on well-established genera when introducing new cultivars. Using Baptisia (false wild indigo) as an example, we’ll explore some past breeding conducted at the Chicago Botanic Garden by Dr. Jim Ault and how this breeding will continue moving forward. This will illustrate how ornamental cultivar development is possible without modern genotyping methods and high input costs.
Speakers
JL

Justin Lombardoni

Chicago Botanic Garden
Thursday September 26, 2024 8:00am - 8:15am HST
South Pacific 4

8:00am HST

PH 3 - Assessing Apple Cultivar Responses to Low Oxygen Limit Determination Using Chlorophyll Fluorescence and Respiratory Quotient
Thursday September 26, 2024 8:00am - 8:15am HST
Dynamic controlled atmosphere (DCA) is a prominent technology used worldwide for long-term apple storage. In Washington, the adoption of DCA technologies to manage low oxygen levels is limited, partly because the benefits are not clearly demonstrated for some major cultivars, such as ‘Honeycrisp’ and new varieties like ‘WA 38’. The response of ‘Honeycrisp’, ‘Gala’, and ‘WA 38’ apples to lower oxygen levels was monitored monthly until 8 months of storage (1oC or 3oC) through chlorophyll fluorescence (CF) and respiratory quotient (RQ) by a stepwise decrease in O2 levels at each time point during 2023/2024 season. Ethanol and acetaldehyde concentrations were obtained from fruit juice before and after the lower oxygen limit (LOL) determinations. ‘Honeycrisp’ and ‘Gala’ apple cultivars showed differences in LOLs determined through CF or RQ. CF LOL for ‘Honeycrisp’ was approximately 0.3-0.2 kPa O2 compared to 0.1 kPa O2 for ‘Gala’ while RQ response occurred at 0.1 kPa O2 level in both cultivars. ‘WA 38’ apples displayed inconsistent CF responses at 0.3 and 0.4 kPa oxygen levels. Ethanol concentration increased after low oxygen stress irrespective of the cultivar. During the first month of storage and after the low oxygen stress, ‘Honeycrisp’ apples accumulated (in average) 120 ppm of ethanol, ‘Gala’ 2.92 ppm, and ‘WA 38’ 4.24 ppm. Towards the end of storage, the ethanol concentration showed an increase for ‘Gala’ (25 ppm), which was not observed for the other two cultivars. Small amounts of acetaldehyde were accumulated only in ‘Honeycrisp’ apples. This study highlights the different responses of apple cultivars to low oxygen stress during the lower oxygen limit (LOL) determination, with ‘Honeycrisp’ being the most sensitive one among the cultivars tested. Further seasons are needed to confirm these results and include the seasonal-dependent responses in each cultivar.
Speakers
HP

Hnin Phyu Lwin

Washington State University
Co-authors
CT

Carolina Torres

Washington State University
DR

David Rudell

USDA-ARS
NA
SA

Sadat Amankona

Washington State University-TFREC
I am a second-year Ph.D student at Washington State University-TFREC
Thursday September 26, 2024 8:00am - 8:15am HST
Nautilus 1

8:00am HST

TCHG 2 - Seed Your Future Horticultural Salary Survey
Thursday September 26, 2024 8:00am - 8:15am HST
What do careers in the horticultural industry pay? To answer this question, Seed Your Future (SYF) in cooperation with the American Floral Endowment (AFE) and North Carolina State University jointly launched an industry-wide salary survey program in Fall 2022. The survey collected salary and benefits information on a broad range of positions from CEO to seasonal workers as well as hiring trends for eight horticultural sectors: floriculture/greenhouse, florist, nursery, landscape, public gardens, fruit/vegetables and other edibles, garden center/markets, and horticultural services. More information on the sectors can be found at: https://research.seedyourfuture.org/. Average production salaries ranging from a low of $30,160 for fruit/vegetable production seasonal workers to $98,590 for public garden production manager. Pay for most positions was above $40,000. Pay for administration positions was higher and ranged from $46,740 for public garden merchandizers and $50,800 for landscape inventory managers to over $100,000 for fruit/vegetable production maintenance managers at $120,580, horticultural services research/development managers at $129,750 and horticultural services sales managers at $132,633. Needless to say, executive positions were the highest paid. While the average salaries for several positions were relatively low, the large range of salaries for those positions indicates that some positions had high pay, likely where employees had greater longevity. Salaries for many of the administrative-type positions were higher and potential horticulture students need to be aware that these positions are open to them as well. Indeed, these positions could be attractive to students as they would allow them to combine a love of plants and horticulture with various other interests such as business management, marketing, IT, graphic design, etc. Overall, the most common benefits for employees were paid time off, professional development and medical. Other common benefits provided include dental, vision, life insurance, and retirement. A host of other benefits reported by individual companies included Employee Stock Ownership Plan, profit sharing, bonuses, short-term/long-term disability, vehicle, phone, purchase discounts, flexible working environment, meals, and wellness days. The outlook is bright. Future hiring plans were mostly split between increasing hiring (51%) and hiring at the same rate (43%). Few businesses in either sector planned to decreasing hiring. For those looking for positions at either large or small business, horticulture has it covered. Of the businesses surveyed, 54% had 21 or more employees and 46% had 20 or fewer employees.
Speakers
JD

John Dole

North Carolina State University
Co-authors
JA

Jazmin Albarran

Seed Your Future
NA
Thursday September 26, 2024 8:00am - 8:15am HST
Kahili

8:00am HST

VCM 4 - Watermelon Rootstock Variety Trial to Understand the Impacts of Grafting on Watermelon Yield and Fruit Quality
Thursday September 26, 2024 8:00am - 8:15am HST
In California, watermelon grafting has been gaining tremendous popularity over other graft-eligible vegetable commodities especially among large-acreage growers. To maintain viability and continued popularity of grafted watermelons in California, we conducted a watermelon rootstock variety trial in 2023 to evaluate the impact of different types of locally popular rootstocks on watermelon yield and quality. Seven watermelon rootstocks, grouped into three distinct types: Interspecific hybrid squash (Cucurbita maxima x Cucurbita moschata), Citron (Citrullus amarus), and Bottled gourd (Lagenaria siceraria), were grafted with a 45-ct field scion, ‘Warrior’ by a commercial greenhouse located in Mills River, NC. All grafted and non-grafted seedlings were then mechanically transplanted into a commercial field near Modesto, CA on 19 April 2023. The trial was arranged as a randomized complete block design with four replications for each treatment. Each plot was 24 m long and contained 13 triploid plants, either grafted or not, alongside four grafted or non-grafted pollenizers. Four harvests were conducted from 25 July to 17 Oct with the help of farm crew. Total yields at each harvest and fruit quality from the first harvest were recorded and compared among rootstock-scion combinations. For quality assessment, fruit length and width were measured with a yardstick. Sugar content (ºBrix) was measured by scooping the central flesh of each halved fruit using a portable reflectometer. Flesh firmness was evaluated using a fruit penetrometer, with measurements taken at spots located one-third and two-thirds of the distance from the blossom end after halving the melon. Rind thickness at the blossom and stem ends were measured using a digital caliper. The overall impact of grafting resulted in an average increase of total yield by 51.5% compared to the non-grafted control (54.7 vs. 36.1 tons per acre) with the most significant difference occurred at the second harvest (27.0 vs. 14.8 tons per acre). Differences of fruit quality between grafted and non-grafted watermelons were primarily observed for fruit firmness. The significant increase of firmness (4.9 vs. 3.4 kg.cm-2) for grafted fruit was also confirmed based on the results of taste sensory evaluation. Slight increases of fruit width and stem end rind thickness after grafting were also found. No changes of ºBrix after grafting were detected. Overall, grafting has proven to be a reliable method for enhancing watermelon yield and maintaining fruit quality in California. Continuous needs assessment will be performed to monitor any pressing issues of watermelon grafting in California.
Speakers
FB

Fayrouz Buojaylah

University ofr California, Cooperative Extension Stanislaus County
Co-authors
ZW

Zheng Wang

Univ. of California Cooperative Extension
Thursday September 26, 2024 8:00am - 8:15am HST
Coral 2

8:00am HST

VSF 3 - Using Biochar As a Soil Amendment in Blueberry Production
Thursday September 26, 2024 8:00am - 8:15am HST
Biochar was tested as a possible soil amendment for blueberry production and compared with pine bark, which is commonly used as a soil amendment in blueberry production in the southeastern United States. Three treatments were established in sandy soil: biochar, pine bark (commercial standard), and control (non-amended soil) in which the variety ‘Farthing’ was planted. Soil characteristics were measured two months and 11 months after the incorporation of the amendments. Plant growth, and physiological traits were measured a year after planting. Biochar increased soil pH compared to pine bark and non-amended soil (control). Organic matter (OM) was higher in pine bark amended soil than in biochar. Biochar increased the Ca/Mg ratio 2 months after its incorporation and maintained P availability compared to the control and pine bark treatments. Eleven months after the incorporation of the amendments, the aluminum content was higher in the soil amended with biochar than in the control, whereas the Fe content was higher in the soil amended with pine bark than in the control. Manganese levels were lower in the pine bark-amended soil than in any other treatment. Plant growth and physiological responses were not affected by the incorporation of biochar as a soil amendment. However, plants established on the pine-bark amended soil had lower Soil Plant Analysis Development (SPAD), stomatal conductance, and maximum fluorescence than blueberry plants established on biochar or non-amended soil.
Speakers
ZR

Zilfina Rubio

University of Georgia
Co-authors
NE

Natalia Espinoza

University of Georgia
NA
Thursday September 26, 2024 8:00am - 8:15am HST
South Pacific 2

8:00am HST

ASHS Conference Central - Thursday Hours
Thursday September 26, 2024 8:00am - 5:00pm HST
Thursday September 26, 2024 8:00am - 5:00pm HST
Coral 4/5

8:00am HST

Exhibit Hall Hours - Thursday
Thursday September 26, 2024 8:00am - 5:00pm HST
Thursday September 26, 2024 8:00am - 5:00pm HST
Coral 4/5

8:15am HST

CE 4 - Pre-breeding Leafy Green Watercress (Nasturtium officinale; Brassicaceae) In an Indoor Vertical Farm: A Discovery Trial
Thursday September 26, 2024 8:15am - 8:30am HST
Our research is to define and develop pre-breeding resources as foundational knowledge to underpin breeding of a specialty leafy green crop watercress (Nasturtium officinale; Brassicaceae). This is being achieved by screening a unique, worldwide collection of watercress population to discover and to enhance nutritional traits for health, morphology, and sensory of the indoor controlled environment agriculture (CEA) market. Watercress is a perennial semi-aquatic leafy green vegetable in the Brassicaceae family and is an understudied specialty crop that has important human health benefits. The most abundant secondary metabolite glucosinolate (GLS) in watercress is gluconasturiin, an aromatic GLS, which hydrolyses and releases phenethyl-isothiocyanates (PEITC). PETIC, specifically from watercress, has been proven to have chemo-preventative potentials. Wild germplasm collection harbours natural variations and useful trait discovery opportunities for introgression of novel traits into the existing gene pool. There is limited interdisciplinary research on crop nutrition and breeding for the CEA settings. We found that watercress is well-suited to indoor hydroponic growing. We established the first indoor vertical farm (VF), a controlled growth chamber in a shipping container, at University of California, Davis. Light quality and quantity both serve important roles in watercress growth and development, and a fully controllable vertical farm allows testing a suite of traits of interests with altered LED light regimes. Results showed that VF grown wild watercress possessed significant genotypic differences across treatments, indicating an abundant natural diversity. Altering red to blue LED light ratio and duration may further enhance the anti-cancer GLS compounds as well as nutritional quality profile of this leafy crop.
Speakers
avatar for Yufei Qian

Yufei Qian

PhD candidate, University of California, Davis
Co-authors
DK

Daniel Klibenstein

University of California, Davis
NA
EK

Ella Katz

University of California, Davis
NA
GT

Gail Taylor

University of California, Davis
NA
Thursday September 26, 2024 8:15am - 8:30am HST
Coral 1

8:15am HST

EcoPhys 2 - Physiological, Biochemical, and Morphological Responses of Achachairu (Garcinia humilis) to Soil Salinity, Flooding, and
Thursday September 26, 2024 8:15am - 8:30am HST
Achachairu (Garcinia humilis (Vahl) C.D. Adams) is a slow-growing tropical fruit tree indigenous to the Amazonian forests in Bolivia. Each tree can produce over 15,000 fruit (400 kg/tree) harvested from cultivated and wild trees. It has significant horticultural potential because the fruit is considered delicious by many people who have tasted it. Thus, its commercial cultivation has extended to Brazil, Mexico, and Australia. The responses and tolerance of this species to abiotic stresses and the use of chemical priming to mitigate stress have never been reported. The study investigated the physiological, biochemical, and morphological responses to flooding and salinity, and the priming with 24-epibrassinolide (EB) to increase flooding and salinity tolerance of G. humilis. Three-year-old achachairu seedlings were used in several sequential experiments, including applying flooding, salinity, and EB priming in different combinations and durations. Physiological variables including leaf gas exchange [net CO2 assimilation (A), stomatal conductance of H2O (gs), and intercellular CO2 concentration (Ci)], leaf chlorophyll index (LCI), and the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) were measured. Leaf and root nutrient concentrations, antioxidant responses, reactive oxygen species (ROS), and lipid peroxidation (MDA) were also measured. Results showed that G. humilis is very tolerant of prolonged flooding of up to 30 d, medium levels of salinity of up to 6 dSm-1, and the combined effect of flooding and salinity. Tolerance to these stresses was exhibited by physiological, biochemical, and morphological responses, consistent with tolerance traits, such as maintaining basal levels of photosynthesis, ion homeostasis, and nutrient balances, robust antioxidant responses to counter ROS increases, and limited lipid peroxidation, all of which may help limit physiological damage. Application of 1.0 mg L-1 EB as a foliar and root-drench before flooding or salinity treatments increased the levels of tolerance of G. humilis to salinity and flooding, most likely by reinforcing antioxidant responses which helped decrease ROS and lipid peroxidation.
Speakers
avatar for Federico Sanchez

Federico Sanchez

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
BS

Bruce Schaffer

University of Florida
HB

Haimanote Bayabil

University of Florida
NA
JH

Jonathan H Crane

University of Florida
MA

Muhammad Adnan Shahid

University of Florida
NA
Thursday September 26, 2024 8:15am - 8:30am HST
Lehua Suite

8:15am HST

FLOR 2 - Hydroponic, Soilless, and Field Produced Cut Flower Bouquets in the Northeast US.
Thursday September 26, 2024 8:15am - 8:30am HST
Cut flower production in the Northeastern United States is restricted by a short growing season. This impacts profitability for many growers and reduces the number of flower options available to them. While there is a reduced selection available, it can still be difficult to select which flowers are profitable and high yielding during a short season. For these reasons, field and controlled environment production of a variety of flowers that could be used in bouquets sold at markets or available for events was investigated. An early- and late-season arrangement was designed utilizing six different plants which could be harvested, assembled, and sold as a bouquet. Two synchronized trials occurred in 2024 with one in the field and the other in the greenhouse. The field plants were germinated indoors and transplanted in a full sun location in USDA Hardiness Zone 5a. The greenhouse plants were grown in three systems which included drip irrigated plants in containers with 4:1 coconut coir: parboiled rice husks, drip irrigated containers filled with rockwool GrowCubes, or hydroponic nutrient film technique. Greenhouse and field plants in both trials were assessed for germination rate and timing; time to flower; flower number, stem length, and subjective quality; and vase life utilizing 3 different floral preservatives. Plants grown in the greenhouse were also compared for adaptability to each growing system. Seeds for the early season bouquet were germinated in April and transplanted into their respective systems in May. Seeds for the late season bouquet were germinated in June and transplanted in July. This information can be used by cut flower growers in the Northeast to potentially extend their season and develop a market for designed “grow-a-bouquet” planting strategies.
Speakers
JS

Jacob Schwab

University of Maine
Co-authors
SB

Stephanie Burnett

University of Maine
NA
Thursday September 26, 2024 8:15am - 8:30am HST
South Pacific 3

8:15am HST

O/LT 2 - Performance of landscape shrubs under three irrigation levels in Arizona
Thursday September 26, 2024 8:15am - 8:30am HST
Fifteen taxa of shrubs growing in a field in Tucson, Arizona were irrigated with three levels of irrigation based on local reference evapotranspiration (ETo) to assess growth and plant quality. Plants established during 2021 under 80% of ETo and in 2022 were irrigated at 20%, 50% or 80% of ETo. Irrigation was applied 2, 9, and 15 times between April 1 and October 31, 2022 for the low, medium, and high irrigation, respectively. Best performing plants were Asclepias linaria ‘Monarch Magnet’, Dodonaea viscosa ‘Emerald Ice’, Eremophila glabra ssp. carnosa ‘Winter Blaze’, Ericameria laricifolia ‘Aguirre’, Hamelia patens ‘Sierra Red’, Leucophyllum frutescens ‘San Antonio Rose’, Leucophyllum langmaniae ‘Rio Bravo’, Tecoma ‘Red Hot’ and Rosmarinus officinalis 'Arp'. Irrigation did not affect plant growth of these nine taxa from April to October. Monthly visual quality assessment of some taxa was temporarily affected by irrigation, however, all performed acceptable or better at the low irrigation with the exception of Asclepias linaria ‘Monarch Magnet’ which had less than acceptable ratings in July and August for the low and high irrigation treatments. This taxa also had 62% mortality of plants under the high irrigation treatment between July and October. Hamelia patens ‘Sierra Red’ plants had frozen to the ground in winter 2022 and started to regrow in May. Five of the taxa (Dodonaea viscosa ‘Emerald Ice’, Eremophila glabra ssp. carnosa Winter Blaze, Ericameria laricifolia Aguirre, Hamelia patens Sierra Red, and Leucophyllum frutescens ‘San Antonio Rose’) maintained a high overall rating at the lowest irrigation treatment. Two field days were held in August and October 2022 where participants from the green industry and related sectors were invited to rate overall appearance, flowering and foliage of one representative plant from each taxa and irrigation treatment. Ratings from field day participants were similar to those from researchers during that month. Most participants’ favorite plants included the five taxa with consistently high overall ratings, only Dodonaea ‘Emerald Ice’ was among the top four favorites at both field days. All nine taxa tested are low water use shrubs that can grow in the landscape with 20% of ETo in the low desert in Arizona. However, some may benefit from additional irrigation during the hottest time of the year for optimum performance.
Speakers
US

Ursula Schuch

University of Arizona
Dr. Schuch is a Professor and Extension Specialist in Environmental Horticulture in the School of Plant Sciences. Dr. Schuch’s research focuses on plant selection and management strategies to conserve water, maintain plant health, and aesthetic function. She is the principal investigator... Read More →
Co-authors
DH

Darren Haver

University of California
NA
JS

Jared Sisneroz

University of California
JG

Jeffrey Gilbert

University of Arizona
NA
KR

Karrie Reid

University of California, Coop Ext
NA
LN

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
LO

Loren Oki

University of California
NL

Natalie Levy

University of California
NA
RC

Ryan Contreras

Oregon State University
SK

Soohyung Kim

University of Washington
YS

Youping Sun

Utah State University
Thursday September 26, 2024 8:15am - 8:30am HST
South Pacific 1

8:15am HST

OPB 1 - Mutagenesis of Hardy Hibiscus Using Ethyl Methanesulfonate
Thursday September 26, 2024 8:15am - 8:30am HST
Hardy hibiscus (Hibiscus moscheutos) are native herbaceous perennial plants. Due to their ornamental nature, variations in flowers, foliage, color, and variety are important. Mutagenesis is a method to increase variation in hibiscus plants, and ethyl methanesulfonate (EMS) is a common chemical mutagen that causes nucleotide substitutions. It converts guanine-cytosine pairs to adenine-thymine pairs. This study aimed to determine the EMS LD50 value for hardy hibiscus. The cultivar ‘Luna Red’ (Ball Horticulture) seed was used for treatment. An EMS LD50 determination study was performed using a factorial randomized complete block design. Three replications of 15 seeds were used for each treatment. EMS treatments consisted of 0, 0.25, 0.5, 0.75, and 1% EMS solution, each treated for 4, 8, and 12 hours to determine the ideal treatment concentration and time. The germination rate, survival rate, and height of seedlings were measured. The interaction effect for germination was insignificant when measuring concentration and time, so the LD50 values were identified for each time separately. The LD50 values for seedling survival were 0.64% EMS for 4 hours, 0.45% EMS for 8 hours, and 0.38% EMS for 12 hours. Notable phenotypic differences between the treated and control plants were observed. There was 92% greater two-month survival in the control plants compared to those treated with 0.75% EMS solution. The control plants were 90% taller at three months after treatment than the plants treated with 0.75% EMS solution.
Speakers
GG

Greta Gallina

University of Georgia
Co-authors
JR

John Ruter

University of Georgia
Allan Armitage Endowed Professor of Horticulture and Director, Trial Gardens at UGA
Thursday September 26, 2024 8:15am - 8:30am HST
South Pacific 4

8:15am HST

PH 3 - Understanding how physiological maturity and storage regime affect skin greasiness on WA 38 apples
Thursday September 26, 2024 8:15am - 8:30am HST
‘WA 38’ (Cosmic Crisp®) is the newest cultivar released by the Washington State University apple breeding program, and today in its sixth year of commercial production in WA. This cultivar has a high pack-out, i.e. highly colored fruit and few external and internal defects. Nevertheless, skin greasiness has been one of the main defects at harvest and postharvest, making waxing during packaging challenging, and affecting the cosmetic appearance. Since the starch degradation index is the only maturity index used to commercially harvest WA 38, the correlation between maturation and the onset of greasiness was studied during two seasons. Different maturity indices pre-and postharvest (firmness, soluble solid content, internal ethylene concentration (IEC), starch index (1-6), IAD values) along with skin greasiness were evaluated from 3-4 weeks before harvest (WBH) until 6 months in air (1oC) or controlled atmosphere (2.5 kPa O2, 1.5 kPa CO2) storage in fruit from four commercial orchards (#1 to #4; 2nd-4th-leaf). In 2022 and 2023 the rate of change of all maturity indices were block-dependent. In both years, IEC was detected in up to 80% of the fruit sampled four WBH in orchard #1 (average 0.3 ppm). At this same time point, only 16% of the fruit had started the starch degradation process (SI=1.5/6.0). The climacteric peak occurred 3-5 months into cold storage, and it was block-dependent. Greasiness on fruit skin was detected 2 WBH in two of the four orchards in 2022; in 2023 this occurred at commercial harvest. Overall, there was a higher incidence (and severity) of greasiness in fruit from air storage compared to CA, and in both cases, it increased during the shelf-life period (7 d at 20oC). The results indicate that fruit greasiness appears to be more related to fruit maturity and perhaps seasonal weather than tree age, nevertheless, additional seasons are needed to confirm these results.
Speakers
CT

Carolina Torres

Washington State University
Co-authors
DR

David Rudell

USDA-ARS
NA
OG

Oswaldo Gonzalez

Washington State University
NA
RM

Rene Mogollon

Washington State University
Thursday September 26, 2024 8:15am - 8:30am HST
Nautilus 1

8:15am HST

TCHG 2 - Horticultural and Plant Science Undergraduate Enrollment Summary Based on Food and Agricultural Education Information System (FAEIS) Data
Thursday September 26, 2024 8:15am - 8:30am HST
There’s a colloquial belief that horticulture-based enrollment in associates, bachelors, master’s, and doctoral degrees across the United States is waning. However, based on data compiled by the Food and Agricultural Education Information System (FAEIS), enrollment in horticultural bachelor majors went from the lowest enrollment in twenty years in 2018 to reach the highest point in last ten years in 2021 (3786 students). Bachelor’s degree enrollment in the West has steadily increased over the last ten years, while remaining level in the South. Enrollment in the Midwest has been generally declining for the last 20 years, while enrollment in the Northeast has been declining since 2015. However, both of the latter regions showed an increase in 2021. The West has the highest proportion of students enrolled in horticulture as a percentage (0.15%) of the total number of public high school graduates. Enrollment in horticultural master’s programs reached a peak in 2018 and has been variable since. Doctoral horticultural enrollment peaked in 2018 and 2019, declining in 2020 and 2021. Associates degree enrollment remained generally level from 2002 to 2019; however, it declined to a ten-year low point in 2020 and recovered by about 1/3 in 2021 to 432 students. Horticulture associates degree students have been predominantly male for the last ten years. However, when turfgrass enrollment is excluded, horticulture disciplines were 42% female and 58% male in 2021. At the beginning of the reporting period, in 2002, horticultural science bachelor programs were predominantly male (62%); by 2021 female enrollment increased to 48%. Over the last twenty years, the gender ratio in horticultural master’s degrees has remained quite consistent with the percent of female students ranging from 44 to 50% and of male students generally a little higher at 46% to 54%. In 2002 about a third of the doctoral graduate students were female, with the percentage increasing over time such that it reached close to parity by 2021 with 52% male and 47% female. Enrollment across all the fields and degrees, except for doctoral, is predominantly White, non-Hispanic. The percentage of bachelor Hispanic students has increased over time, representing the largest ethnic group after White, non-Hispanic. Asian student numbers also increased but not to the same level as Hispanic students. The percentage of non-US citizens in doctoral degrees has been quite high for many years across all the plant-related areas and was often the largest category. Implications are discussed.
Speakers
JD

John Dole

North Carolina State University
Co-authors
MK

Melinda Knuth

North Carolina State University
Thursday September 26, 2024 8:15am - 8:30am HST
Kahili

8:15am HST

VCM 4 - Effect of Biofungicides Containing Trichoderma and Grafting on Watermelon Productivity and Plant Health
Thursday September 26, 2024 8:15am - 8:30am HST
The goal of the project is to evaluate the potential of reducing chemical fumigation in California's watermelon production using grafting and Trichoderma-based biofungicide. Two field experiments in 2022 and 2023 were implemented within commercial watermelon fields in Stockton and Modesto, CA. Each trial included three rootstocks (Cobalt, Flexifort, and RS841) grafted onto a 45-ct scion (Summer Breeze). Two Trichoderma-containing products were applied to the grafted and nongrafted seedlings through tray soaking at one day before transplanting or field chemigation at 30 and 62 days after transplanting (DAT). The application rates for soaking and chemigation were 45 g.75 L-1 of water and 2.2 kg.ha-1, respectively. All seedlings were mechanically transplanted during mid-May of both years into a split-split plot design with the Trichoderma product as the main factor and application method as the sub-plot. All treatments were replicated four times. Each treatment row was 18.6 m long and contained ten grafted or nongrafted triploids and three grafted or nongrafted pollenizers. Vine health was visually assessed three times for symptoms associated with soil-borne fungal pathogens. Canopy coverage was measured starting at 22 DAT in 2022 and 40 DAT in 2023 and thereafter at an approximate interval of two weeks for a total of six measurements. Harvest was conducted three times in 2022 and twice in 2023 to analyze yield and quality differences among treatments. Runner and root samples were taken amid the harvest and shipped to the UC Davis Fungal Pathology Lab for further identification. Results indicated that the Trichoderma-containing bio-fungicides were not as effective as grafting on preventing vine decline and maintaining canopy coverage in both trials. The synergistic effects of grafting and Trichoderma inoculation provided some but limited benefits to plant health compared to the single factor of grafting. The overall influence of biofungicides on yield was also less notable than that of grafting regardless of application method. For fruit quality, grafting dominated the impacts over biofungicides on fruit firmness and rind thickness in both trials. Charcoal rot (Macrophomina phaseolina) with other putative co-infestations of Fusarium pathogens were diagnosed from nongrafted inoculation-free plots in 2022 while no significant soil-borne diseases were identified from 2023. Overall, grafting with multi-pathogen resistant rootstocks prove to be a reliable method for enhancing watermelon yield while maintaining crop health. More work is still needed to further explore the optimal application protocols tailored to grower’s farming system to maximize the effects of biofungicide.
Speakers
FB

Fayrouz Buojaylah

University ofr California, Cooperative Extension Stanislaus County
Co-authors
ZW

Zheng Wang

Univ. of California Cooperative Extension
Thursday September 26, 2024 8:15am - 8:30am HST
Coral 2

8:15am HST

VSF 3 - Effects of Aged Pine Bark Amendments on Container-Grown Southern Highbush Blueberry Growth and Substrate Properties
Thursday September 26, 2024 8:15am - 8:30am HST
Blueberry cultivation is rapidly expanding due to a dramatic increase in the consumption of the fruit. Soilless substrates have been viewed as a method to increase the production and geographic availability of this fruit. The identification of optimal and alternative substrates for the growth and development of the plants is needed to further guide a new and growing industry. The purpose of this study was to investigate the suitability of aped pine bark substrates amended with coconut coir or wood fiber substrates produced from Pinus taeda for container production of southern highbush blueberry (Vaccinium sp.). Plant linears of ‘Star’ blueberry were grown in 7.3-L pots filled with substrates consisting of coconut coir, aged pine bark, and hammermilled wood fiber. These were each amended at three rates (0%, 20%, 40%, 60%, 80%, and 100%). The plants were harvested at 0 days, 70 days, 140 days, and 365 days to assess their growth and development, measuring plant dry weight at each interval. Additionally, the substrate's physical properties, including particle size and air space, were measured during these four periods to determine the degradation and its influence on substrate quality over time. The findings of this study suggest that coconut coir usage can be reduced by using wood fiber or aged pine bark due to the positive effect on early vegetative blueberry growth.
Speakers
BS

Brandan Shur

North Carolina State University
Co-authors
BJ

Brian Jackson

North Carolina State University
NA
Thursday September 26, 2024 8:15am - 8:30am HST
South Pacific 2

8:30am HST

CE 4 - Planting Density on the Growth and Production of Select Fruiting Crops in Aquaponic Systems
Thursday September 26, 2024 8:30am - 8:45am HST
Traditionally, aquaponic systems are used to produce leafy greens and herbs, while fruits and fruiting vegetables have been considered more difficult to grow due to additional nutrient requirements. When nutrients are not a limiting factor, the possibility of producing more fruit per square foot by increasing planting density is tempting as global populations increase and agricultural land area decreases. This study examined the effects of two different densities on banana peppers (Capsicum annuum L. var ‘Goddess F1’) and pole beans (Phaseolus vulgaris L. ‘Seychelles OG’) in a 20 sq ft grow bed. High densities consisted of 14 and 22 pepper and bean plants respectively, while low densities were 7 and 11 pepper and bean plants. Higher densities of peppers and beans produced more fruits than lower densities, while plant dry biomass of higher densities appeared to be lower than higher densities. Results suggest that higher planting densities of peppers and beans may increase harvestable fruit.
Speakers
TH

Teal Hendrickson

Oklahoma State University
Co-authors
BD

Bruce Dunn

Oklahoma State University
MS

Mitchell Sommer

Symbiotic Aquaponic
NA
Thursday September 26, 2024 8:30am - 8:45am HST
Coral 1

8:30am HST

EcoPhys 2 - Plant Physiological and Root Anatomical Responses of Two Novel Olive Cultivars (‘Oliana’ and ‘Lecciana’) Under Salinity
Thursday September 26, 2024 8:30am - 8:45am HST
Soil salinity poses a significant challenge in agriculture, disrupting the normal functioning of plants by reducing water and nutrient uptake. Olive trees (Olea europaea), common in Mediterranean regions, exhibit moderate to high tolerance to salinity, varying by cultivar. Interest in cultivating olive trees is growing in Florida’s coastal areas, characterized by poorly drained soil and low-quality groundwater, leading to salt accumulation in the root zone. The high salinity levels in these areas present a significant challenge for crop cultivation. Therefore, introducing new salt-tolerant cultivars is necessary to mitigate salinity stress. This study aimed to evaluate the plant physiological and root anatomical responses of two novel olive cultivars - ‘Oliana’ and ‘Lecciana’ - to salinity stress, assessing their salt tolerance. Eight-month-old plants were grown in pots using a sand medium under greenhouse conditions and treated with varying salt concentrations (0 mM, 50 mM, and 100 mM). The experiment followed a completely randomized design with three replications, each consisting of nine plants. Plants were irrigated at weekly intervals with half-strength Hoagland solution to meet their nutrient requirements. Height and trunk diameter were measured at four different time points (0, 15, 30, and 45 days). At the end of the trial, plants were destructively sampled for biomass, nutrient content, and root anatomical measurements at the latter three time points. Significant differences were observed in height, trunk diameter, and nutrient contents between the control and NaCl treatments. These findings serve as a baseline for the commercial development of salt-tolerant olive cultivars.
Speakers
KH

Khalid Hussain

University of Florida
NA
Co-authors
JF

John-Paul Fox

University of Florida
LR

Lorenzo Rossi

University of Florida
Thursday September 26, 2024 8:30am - 8:45am HST
Lehua Suite

8:30am HST

FLOR 2 - Influence of Varietal Differences and Cutting Lengths on the Rooting Abilities and Growth Performances of Bougainvillea
Thursday September 26, 2024 8:30am - 8:45am HST
Bougainvillea spp. a difficult root ornamental plant does not root easily requiring the need for growth regulators. Moreover, the varieties have high aesthetic values and commercial florist desires. Experiments were conducted at the Federal University of Agriculture, Abeokuta Nigeria to determine the effect of varietal differences and cutting length on the rooting ability and growth of Bougainvillea plants. The experiment was a completely randomized design replicated three times. The cutting lengths had a significant effect on the number of leaves produced, with the highest leaf production observed for the 15cm cutting lengths in B. glabra variegata and B. glabra white plants, 5cm cuttings however produced the highest number of leaves in B. spectabilis variety. The cutting length also has a significant effect on the heights produced in the three varieties of Bougainvillea plants where 15cm cutting produced the highest plant heights in B. glabra variegata and B. glabra white varieties which were significantly different from those obtained from the 10cm cuttings, However, 5cm cuttings produced the highest plant heights in B. spectabilis. The interaction effect of cutting length and variety was significant (p
Speakers
OO

Olatunde Olosunde

Federal University of Agriculture, Abeokuta
NA
Thursday September 26, 2024 8:30am - 8:45am HST
South Pacific 3

8:30am HST

O/LT 2 - Performance of Landscape Plants in California’s Central Valley Under Three Levels of Deficit Irrigation
Thursday September 26, 2024 8:30am - 8:45am HST
To develop landscape irrigation recommendations, 22 taxa of landscape plants were evaluated under three levels of deficit irrigation in a field trial. The taxa consisted of common horticultural perennials and shrubs including multiple cultivars of Hibiscus syriacus, Nandina domestica, Rosa spp., and Salvia spp. Based on anticipated plant size and cultural requirements, taxa were planted in one of three adjoining fields, with each field laid out in a grid pattern with either 2 or 3 meter spacing between rows and between individual plants in each row. All fields were covered with a 2-3” layer of chipped bark mulch. For each taxon, 24 individuals were planted with eight replicates per irrigation treatment in a randomized complete block layout with both taxa and irrigation treatment being randomly assigned. Plants were installed in March as bareroot inputs, with containerized plants installed from April to early June of 2021. Daily reference evapotranspiration (ETo) values from a local weather station were obtained from the California Irrigation Management Information System. The amount of plant available water (PAW) for the trial site was obtained from the US Geological Survey via the Soilweb application. In 2021, plants were irrigated regularly to fully establish their root systems. From April to October 2022, plants were irrigated with one of three deficit irrigation treatments equal to 80%, 50%, or 20% of ETo. The treatments functioned similarly to a crop coefficient to modify daily ETo values. The modified ETo values were used to estimate when 50% of PAW was depleted for each treatment. Irrigations occurred whenever this threshold was reached, with the volume of water applied being equal to 50% of PAW. The volume applied at each irrigation was constant across treatments with the frequency between irrigations varying by treatment. As a result, the 80% treatment was irrigated most frequently with the 20% treatment was irrigated thrice during the deficit period. Monthly during the deficit period, each plant was rated on six categories of aesthetic quality and length, width, and height measurements were collected to develop a plant growth index. Aesthetic performance between the treatments was compared using an ANOVA in conjunction with Tukey’s HSD post-hoc test in R. A majority of the taxa evaluated maintained acceptable aesthetic quality ratings on the lowest irrigation treatment. Two taxa evaluated, Lagerstroemia ‘SMNLCIBF’ Center Stage® Red and Rosa ‘ChewPatout’ Oso Easy® Urban Legend achieved high levels of aesthetic performance on the 20% treatment.
Speakers
JS

Jared Sisneroz

UC Davis
Mr. Sisneroz is the project manager of the UC Landscape Plant Irrigation Trials (UCLPIT) and the ‘Climate Ready Landscape Plants’ programs. He specializes in landscape plant water-use efficiency research and water resource management.
Co-authors
DH

Darren Haver

UC Agriculture and Natural Resources
NA
KR

Karrie Reid

UC Agriculture and Natural Resources
NA
LN

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
LO

Lorence Oki

University Of California, Davis
RC

Ryan Contreras

Oregon State University
SK

Soohyung Kim

University of Washington
US

Ursula Schuch

University of Arizona
YS

Youping Sun

Utah State University
Thursday September 26, 2024 8:30am - 8:45am HST
South Pacific 1

8:30am HST

OPB 1 - Genetic Sterilization of Four Invasive Ornamental Plant Species to Reduce Their Invasive Potential: Progress and Prospects
Thursday September 26, 2024 8:30am - 8:45am HST
Invasive ornamental plants have been considered as a major contributor to the spread of invasive plant species in the United States and many other countries in the world. To mitigate the economic and ecological impacts of invasive ornamental plants, we have focused on genetic sterilization of four invasive ornamental plants that are commonly produced and widely used in Florida to develop sterile, triploid cultivars as alternatives to the invasive types. Toward this goal, we have made progress in (1) artificial induction of tetraploids in nandina, privet, and porterweed, 2) developing and releasing new sterile, non-invasive triploid lantana cultivars, 3) understanding the reproductive biology of lantana, 4) developing and applying new genomic and molecular tools, and 5) testing alternative breeding approaches. By applying the mitotic inhibitor agent colchicine to germinating seeds or seedlings, we have induced tetraploids in nandina, privet, and porterweed. Tetraploid nandina showed significantly reduction in pollen stainability and seed set. Tetraploid privet lines exhibited thicker leaves with darker green color. Induced tetraploid nandina, porterweed, and privet lines have come into flowering, and interploidy crosses are made to produce new triploids. Using existing tetraploids in lantana, we have generated hundreds of new triploids, evaluated their male and female sterility, and released five sterile, non-invasive triploid cultivars, three of which have become popular replacements of the invasive types. Ploidy and molecular marker analyses have revealed the production of unreduced female gametes and apomictic seeds in lantana and natural sexual polyploidization in lantana and several other lantana species. Genome and transcriptome analyses have uncovered candidate genes that are linked or directly involved in the production of unreduced female gametes in Lantana. A number of diploid and tetraploid lantana genotypes with male or female sterility have been identified, which are being used to generate new triploids through open pollination. Additional tools are needed to rescue triploid embryos and screen breeding populations for high female sterility. These new plant materials, genetic and genomic resources, and molecular tools are expected to facilitate the genetic sterilization of lantana, nandina, porterweed, and privet. The findings may guide similar genetic sterilization efforts in other invasive ornamental plants.
Speakers
ZD

Zhanao Deng

University of Florida
Co-authors
AS

Alexander Schaller

University of Florida
NA
BP

Brooks Parrish

University of Florida
MF

Mohammed Fetouh

Tanta University
NA
SW

sandra wilson

University of Florida
Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral... Read More →
Thursday September 26, 2024 8:30am - 8:45am HST
South Pacific 4

8:30am HST

PH 3 - Chlorophyll to Carotenoid Ratio Measured Nondestructively Correlates with Peel Pigment Content and Canopy Attachment Position of ‘Granny Smith’ Apples
Thursday September 26, 2024 8:30am - 8:45am HST
‘Granny Smith’ is an important apple variety for Washington State, where it has consistently been ranked as the third most-produced conventional cultivar since 2017. This apple variety is highly susceptible to sunscald, a sun-stress-related postharvest disorder that typically appears after three months of cold storage and makes apples unmarketable. Previous research has shown that a decrease in chlorophyll (chl) and an increase in carotenoids (car) in fruit peel have been associated with increased sunlight exposure and the development of sunscald. In order to assess the use of the chl/car ratio measured non-destructively with a Vis/NIR hyperspectral imager as a predictive index for sun exposure and sunscald development postharvest, ‘Granny Smith’ apples were picked from the periphery and inner canopy sections of the tree in 2021 and 2023 seasons. Fruit position in the canopy was documented during sampling and later correlated with hyperspectral images, chlorophyll, and carotenoid content in the peel. Subsequently, the collected peel sample was immediately frozen with liquid nitrogen and stored at -80°C. The chl/car ratio obtained from the reflectance values from the hyperspectral images was well correlated (r2 = 0.82) with the destructive determination of the ratio. Based on k-means clustering analysis, samples were grouped in accordance with the chl/car ratio and associated with fruit position on the tree. Apples with the highest chl/car ratios (1.4 to 1.7) were those located on the shaded portion of the trees. Apples with sunburn had the lowest chl/car ratios (0.1 to 1.2) and were located on the periphery of the tree. The results indicate that the chlorophyll to carotenoid ratio measured non-destructively at harvest can potentially be used for pre-storage sorting of ‘Granny Smith’ apples based on relative sun exposure and sunscald susceptibility, reducing postharvest losses. However, the establishment of the index reliability can benefit from additional years of data collection.
Speakers
avatar for Manoella Mendoza

Manoella Mendoza

WA State University
Co-authors
CT

Carolina Torres

Washington State University
DR

David Rudell

USDA - ARS
NA
LK

Lee Kalcsits

Washington State University
NA
RM

Rene Mogollon

Washington State University
Thursday September 26, 2024 8:30am - 8:45am HST
Nautilus 1

8:30am HST

TCHG 2 - Creating a Sustainable Vegetable Production Registered Apprenticeship Program: A Review of Curriculum Development and Lessons Learned
Thursday September 26, 2024 8:30am - 8:45am HST
The average age of principal farm operators was 58.1 years in 2022. With this reality, agricultural educators, extension personnel, and agricultural businesses are looking for innovative strategies to recruit and effectively train the next generation of diverse farm operators. On-farm apprenticeships in the U.S. are an increasingly popular method of training future farmers. However, these apprenticeships tend to be informal with little or no formal curriculum. Registered apprenticeships are an emerging trend in workforce development with rapidly increasing popularity among non-traditional trade occupations such as healthcare and information technology, but are still relatively new in agriculture. Registered apprenticeship programs have been shown to help recruit and develop a diverse and highly skilled workforce, increase productivity, allow employers to participate in training, and increase job retention. At the Center for Environmental Farming Systems (CEFS), we developed North Carolina’s first two registered agricultural apprenticeship programs. This session will cover the basic components of registered apprenticeships and how they can meet the growing need for skilled farm labor in vegetable operations. We will share how we created the Sustainable Vegetable Production Apprenticeship in North Carolina, including curriculum development, administrative logistics, and the opportunities and challenges associated with registered agricultural apprenticeships. We will also share reflections on the successes and challenges of our first three years of the program. During the first two pilot cohorts we had 123 applications with more than 40 applications from military veterans with 13 veterans joining the apprenticeship program. Our pilot program demonstrates that registered agricultural apprenticeships are a viable pathway for recruiting and effectively training veteran and minority beginning farmers.
Speakers
AC

Angel Cruz

North Carolina State University
Research Scholar at NC State University
Co-authors
KW

Kathleen Wood

North Carolina State University
NA
SK

Sara Kidd

North Carolina State University
NA
Thursday September 26, 2024 8:30am - 8:45am HST
Kahili

8:30am HST

VCM 4 - Canary Melons Cultigen Yield and Quality Evaluations in North Carolina, 2023
Thursday September 26, 2024 8:30am - 8:45am HST
Canary melons, Cucumis melo var. inodorus, are grown in the United States, with most acreage produced in California and Arizona. There is very limited production acreage in the southeastern United States, including North Carolina. No statistics are gathered by USDA on canary melons as this type of melon is truly a specialty melon. The goal of this study was to determine how well adapted canary melon cultigens are with respect to yields and quality when grown in North Carolina and to gauge the possibilities of producing this crop as a commercial option in the state. Fourteen cultigens were evaluated from eight different seed companies for yield and size over 16 harvests, flesh firmness and sweetness, and shape and rind characteristics. Statistical design was a randomized complete block with four replications and mean separation across measures was conducted using a LSD test at the P
Speakers
JS

Jonathan Schultheis

North Carolina State University
Jonathan Schultheis is a Professor in the Department of Horticultural Science at North Carolina State University. He has worked exclusively with North Carolina State University for over 35 years. He research and extension work primarily involves cucurbit crops and sweetpotatoes. Key... Read More →
Co-authors
AP

Andrew Pfefferkorn

North Carolina State University
NA
BS

Baker Stickley

North Carolina State University
BP

Brandon Parker

North Carolina State University
NA
SM

Stuart Michel

NC State University
Thursday September 26, 2024 8:30am - 8:45am HST
Coral 2

8:30am HST

VSF 3 - Ground Covers Shape Canopy Microclimate And Fruit Quality Components In A Blueberry Orchard
Thursday September 26, 2024 8:30am - 8:45am HST
Fruit quality parameters are typically reported by growers and researchers as an average. However, for small fruits such as blueberries, berry-to-berry variability in texture and flavor also impacts the consumer eating experience. The objective of this project was to capture how the uniformity of fruit quality parameters varies by 1) cultivar, 2) berry maturity, and 3) exogenous phytohormone applications. From 2022-2023, analyses were conducted on individual blueberries from multiple studies carried out in commercial fields in Michigan. First, we compared the uniformity of berry mass, diameter, firmness, and total soluble solids (TSS) in six northern highbush blueberry cultivars: “Duke,’ ‘Bluecrop,’ ‘Draper,’ ‘Calypso,’ ‘Elliott,’ and ‘Aurora.’ The uniformity was highest/lowest for berry mass in 'Bluecrop'/'Calypso', firmness in 'Bluecrop’ /‘Aurora,’ and TSS in 'Bluecrop'/'Elliott'. Second, we evaluated how changes in berry maturity due to delayed harvest affected the uniformity of berry mass, diameter, firmness, TSS, pH, total acidity (TA), TSS/TA, and aroma volatile concentrations in: ‘Duke,’ ‘Draper,’ and ‘Calypso’. Delayed harvest did not alter the uniformity of berry mass or TSS, but increased the uniformity of TA and TSS/TA in all three cultivars. The implications of delayed harvest on the uniformity of consumer liking scores will also be discussed. Finally, we tested whether exogenous application of multiple phytohormones impacted the uniformity of berry mass, diameter, firmness, and TSS in ‘Bluecrop’ and ‘Elliott’. Abscisic acid improved the uniformity of berry mass in 'Elliott,' but not firmness or TSS. Meanwhile, jasmonates had a limited effect on the uniformity of fruit quality parameters in 'Bluecrop'. The relative importance of the "average" and "uniformity" of fruit quality parameters will be discussed. We conclude that “uniformity” is an important component of fruit quality in blueberry.
Speakers
JV

Josh VanderWeide

Michigan State University
Co-authors
RI

Rufus Isaacs

Michigan State University
NA
SL

Sheng-yang Li

Michigan State University
NA
SV

Steve Van Timmeren

Michigan State University
NA
Thursday September 26, 2024 8:30am - 8:45am HST
South Pacific 2

8:45am HST

CE 4 - Planting Density and the Growth of Kale and Cilantro in Year-round Aquaponics
Thursday September 26, 2024 8:45am - 9:00am HST
Use of aquaponic systems has the potential to provide sustainable food production in a variety of environments year-round. Unfortunately, little is known about the limitations of aquaponics regarding planting density in a grow bed and year-round growing outside of tropical climates. This study evaluated two different planting densities of kale (Brassica oleracea var. acephala L. ‘Winterbor’) and cilantro (Coriandrum sativum L. ‘Cruiser’) in a 20 sq ft grow bed in a hoophouse grown during winter and early spring in Stillwater, OK, using bluegill (Lepomis macrochirus L.) as the fish species. High planting densities comprised of 54 kale plants and 68 cilantro plants. Low densities contained 36 kale plants and 48 cilantro plants. High planting density reduced fresh weight and chlorophyll content in kale, and chlorophyll content in cilantro. Additionally, total nitrogen content decreased at higher densities of kale while sulfur content increased. Cold weather mitigation was utilized in the form of a secondary plastic covering, extra light sources, and in-line heaters. Results suggest that higher planting density may be feasible for some leafy green and herb species while being detrimental to others and that year-round growing may be possible with the addition of inline water heaters.
Speakers
TH

Teal Hendrickson

Oklahoma State University
Co-authors
BD

Bruce Dunn

Oklahoma State University
MS

Mitchell Sommer

Symbiotic Aquaponic
NA
Thursday September 26, 2024 8:45am - 9:00am HST
Coral 1

8:45am HST

EcoPhys 2 - Continuous monitoring of tree water status using microtensiometers for irrigation management in olive
Thursday September 26, 2024 8:45am - 9:00am HST
Water scarcity is challenging agricultural production, demanding more precise and efficient irrigation management. Plant-based continuous monitoring has emerged as a promising approach for detecting water stress progression and optimizing irrigation. However, its practical implementation is hindered by the complex interpretation of the sensors’ outputs and plant physiological status relationships. Plant water potential is among the most robust water status indicators and is widely used for irrigation management. Nevertheless, its measurement is time-consuming and requires skilled personnel, making it difficult to have frequent assessments. In this study, we explored the potential of using continuous water potential sensing to quantify olive water status and its response to irrigation. Specifically, we compared continuous and discrete tree-level measurements of water status using microtensiometers and the pressure chamber, respectively. The microtensiometers proved effective in capturing tree water status dynamics, enabling a prompt assessment of the impact of irrigation practices. Preliminary analyses show a good linear correlation between midday trunk and stem water potential values obtained with microtensiometers and the pressure chamber, with the former being less than 0.5 MPa lower, a difference that could be attributed to the specific measurement of each technique. Importantly, having continuous data allows the extrapolation of several water status parameters which can provide key information in addition to the single timepoint midday values. Overall, this study suggests microtensiometers can be a useful tool to optimize water application in olive orchards.
Speakers
PG

Paula Guzman-Delgado

University of California Davis
Co-authors
AP

Amrit Pokhrel

University of California Davis
NA
ES

Emily Santos

University of California, Davis
NA
KS

Kosana Suvočarev

University of California Davis
NA
Thursday September 26, 2024 8:45am - 9:00am HST
Lehua Suite

8:45am HST

FLOR 2 - Influence of UV-A Night Interruption Lighting on the Growth of Potted Basil Plants
Thursday September 26, 2024 8:45am - 9:00am HST
Basil (Ocimum basilicum) is one of the most popular culinary herbs sold in containers, but plants can quickly become tall, leggy, and unmarketable. Chemical plant growth regulators (PGRs) are not labelled for use on herbs, so there is a need for a nonchemical alternative. Ultraviolet radiation (UV) has been shown to be an effective alternative to PGRs on ornamentals, but there are no guidelines for effective use of UVA in potted basil production. Therefore, the objectives of this study were to determine the stage of development plants should be exposed to UVA radiation and the effective duration. Fifteen seeds of either sweet basil cultivars ‘Nufar’ or ‘Genovese’ were sown into 15-cm containers. The containers were placed in a glass-glazed greenhouse at 23 °C and under a 16-h photoperiod (LD) provided by LED supplemental lighting or under a 9-h photoperiod and 6-h night interruption lighting providing 385 nm of UVA radiation at an intensity of 20 µmol∙m–2∙s–1. Seeds were germinated for one week under either LD or UVA and then grown for 3 weeks under 10 treatments. The treatments included: LD entire time, LD 1 week-UV 2 weeks, LD 1.5 Weeks-UV 1.5 Weeks, LD 2 weeks-UV 1 week, LD 1 week-UV 1week-LD 1week, UV entire time, UV 1 week-LD 2 weeks, UV 1.5 weeks-LD 1.5 weeks, UV 2 weeks-LD 1 week, and UV 1 week-LD 1week- UV 1 week. Both cultivars responded differently to UVA radiation. Generally, plants grown under UVA from germination to harvest were the most compact. For example, ‘Genovese’ under UV entire time were 3.6 cm shorter than plants under LD entire. However, the chlorophyll content and dry mass of ‘Genovese’ were reduced by 33 and 53%, respectively, when exposed to UV entire compared to plants under LD entire. Additionally, if the treatment a plant ended under was LD, the chlorophyll content was generally higher than those ending under UV. Therefore, the most compact and green potted basil ‘Nufar’ and ‘Genovese’ were those grown under UV 2 weeks-LD 1 week.
Speakers
SB

Seth Benjamin

Michigan State University
Co-authors
RL

Roberto Lopez

Michigan State University
NA
Thursday September 26, 2024 8:45am - 9:00am HST
South Pacific 3

8:45am HST

O/LT 2 - Field Trials of Landscape Plants under Reduced Irrigation Frequency
Thursday September 26, 2024 8:45am - 9:00am HST
Utah has experienced significant drought conditions, with 99.3% of the land under drought stress from the previous year to the present. In response to this challenge, deficit irrigation landscapes are gaining popularity in arid regions. This study aimed to investigate the overall appearance, plant growth, and physiological response of ten ornamental plants to deficit irrigation. The selected species include Caryopteris ×clandonensis ‘Blauer Splatz’ (Sapphire SurfTM bluebeard), Cercis canadensis (eastern redbud), Cercis occidentalis (western redbud), Cotoneaster ×suesicus ‘OSUCOT2’ (Emerald BeautyTM cotoneaster), Hesperaloe parviflora ‘Straight Up Red’ (‘Straight Up Red’ texas red yucca), Miscanthus sinensis ‘NCMS2B’ (bandwidth maiden grass), Physocarpus opulifolius ‘Diabolo’ (Diabolo® ninebark), Physocarpus opulifolius ‘Little Devil’ (Little DevilTM ninebark), Rosa ×hybrida ‘Meifranjin’ (Blushing Drift® rose), and Vitex agnus-castus ×rotundifolia ‘Helen Froehlich’ (Summertime BluesTM chaste tree). Eight plants per species were randomly assigned to one of three deficit irrigation frequencies, calculated based on 80% reference evapotranspiration (ETo) (high), 50% ETo (medium), and 20% ETo (low) at the Utah Agriculture Experiment Station’s Greenville Research Farm, North Logan, UT, USA. The overall appearance was evaluated biweekly, spanning from 30 Jun to 31 Oct 2023. Plant growth and stomatal conductance were recorded monthly during the growing season. The growth of plants was not significantly affected by reduced irrigation frequency. However, the impact of deficit irrigation on aesthetic performance and stomatal conductance was notable, particularly during August and September. The results highlight variability in plant performance across species, with Caryopteris ×clandonensis and Cotoneaster ×suesicus showing consistent performance across irrigation levels. However, Cercis canadensis and Physocarpus opulifolius ‘Diabolo’ exhibited a more pronounced difference under varying irrigation levels. Funding Source USDA Agricultural Marketing Service Specialty Crop Multi-State Program, USDA NIFA Hatch project UTA01666, 2022 Extension Water Initiative Grants Program, Utah State University’s Center for Water-Efficient Landscaping, and the Utah Agricultural Experiment Station
Speakers
ZW

Zirui Wang

Utah State University
Co-authors
YS

Youping Sun

Utah State University
Thursday September 26, 2024 8:45am - 9:00am HST
South Pacific 1

8:45am HST

OPB 1 - Inheritance and Genetics of Ornamental Traits in Pomegranates
Thursday September 26, 2024 8:45am - 9:00am HST
Pomegranates, renowned for their fruit, also possess ornamental varieties with unique traits such as double flowering, diverse flower colors, and dwarfing characteristics. Despite their appeal, limited information exists on the genetics and inheritance of these ornamental traits. In this study, we investigated the inheritance and genetic controls of these traits through crosses between the dwarfing cultivar Peppy Le Pom and pomegranate cultivars showcasing ornamental traits. By analyzing multiple families and conducting a genome-wide association study (GWAS) using resequencing data from 64 cultivars, we made several key findings. Firstly, the double flower trait exhibited Mendelian inheritance with a single locus controlling its expression, as evidenced by a 1:1 ratio of double to single flower plants in the F1 generation where a double flower individual was crossed onto a single flower individual. Subsequent analysis identified a SNP within an AP2-like gene on chromosome 3 that was able to differentiate between a single and double flower phenotype. Secondly, flower color inheritance revealed the recessive nature of white flowers compared to orange and red hues. SNPs near a PGLOX gene, previously linked to anthocyanin-less pomegranates, distinguished between white and red/orange flowers, suggesting specific genetic loci involved in determining flower color. Lastly, the dwarfing trait was identified as recessive, exhibiting phenotypic diversity among selfed F1 individuals, indicating potential multiple loci control. Further investigation into the genetic mechanisms governing dwarfing is warranted. In conclusion, our study contributes to understanding the genetic underpinnings of ornamental traits in pomegranates, offering insights valuable for breeding programs aimed at developing novel varieties with desirable ornamental characteristics. Further research into the identified genetic loci promises to enhance our understanding and facilitate targeted breeding efforts in this versatile fruit species.
Speakers
AS

Alexander Schaller

University of Florida
Co-authors
JC

John Chater

University of Florida
ZD

Zhanao Deng

University of Florida
Thursday September 26, 2024 8:45am - 9:00am HST
South Pacific 4

8:45am HST

PH 3 - Early Spectral Differences on Scald Disorders in ‘Granny Smith’ Apples
Thursday September 26, 2024 8:45am - 9:00am HST
‘Granny Smith’ apples are highly susceptible to skin browning (=scald). These disorders can significantly reduce fruit’s marketability due to their unattractive appearance. Superficial scald and sunscald have different etiologies but their symptoms are similar and easily mistaken. The oxidation of α-farnesene causes superficial scald (SS); on the other hand, sunscald (SC) is a non-oxidative process that affects only the sunlit sides of the fruit. To correlate the spectral fingerprint with fruit susceptibility to these disorders, hyperspectral images (400-1000 nm, 640x865 px; Headwall Photonics, Bolton, MA) were taken at harvest from sun-exposed and unexposed sides of the fruit (n=216; ~26,000 px) and later, after six months in air storage (33 oF), correlated with scald incidence. The dataset grouped 145 asymptomatic, 117 with SS and 170 with SC fruit. After pre-processing spectral information (Savitzky-Golay dev, standard normal variate), iPLS wavelength selection showed that bands from 400 to 650 and 900 to 950 nm were the most accurate for at-harvest spectral differentiation between superficial and sunscald symptoms. A neural network classification model was trained (18,226 px) and validated on an independent dataset (7,808 px), achieving overall accuracies of 78 % and 73 %, respectively. After prediction, SC px obtained the highest classification metrics (accuracy 87 %, precision 86 %); meanwhile, the asymptomatic class showed the lowest metrics (accuracy 74 %, precision 60 %). These preliminary results showed that in the same way, sunscald could be identified close to harvest using hyperspectral fingerprints, superficial scald could also be predicted at harvest on susceptible fruit and differentiated from sunscald susceptible fruit.
Speakers
RM

Rene Mogollon

Washington State University
Co-authors
CT

Carolina Torres

Washington State University
DR

David Rudell

USDA-RS
NA
MM

Manoella Mendoza

WA State University
Thursday September 26, 2024 8:45am - 9:00am HST
Nautilus 1

8:45am HST

TCHG 2 - Impact of Greenhouse Training Online Program
Thursday September 26, 2024 8:45am - 9:00am HST
Availability of trained labor is a challenge for greenhouse and nursery growers in the U.S., and access to online education is limited in many countries. To supply this need, the Greenhouse Training Online extension program was initiated in 2015 at the University of Florida (UF). The goal of the program is to deliver bilingual professional development training on horticultural science. Four-week courses on crop management topics (basic skills, nutrients, weeds, diseases, water quality, climate management, and economics) are delivered in English and Spanish using an eLearning platform. Each course consists of eight pre-recorded lessons and associated assignments, with interactive feedback provided by instructors via email or discussion forums. Mandatory pre- and post- evaluation surveys were used to measure impacts. For 2023, a total of 563 participants enrolled in seven courses with 473 successfully completing requirements (84%). The completion rate is high for an extension program because of asynchronous delivery across time zones and work schedules, specific deadlines, a course fee to increase perceived value, interaction with instructors to customize instruction, and a certificate of completion as a graduation reward. Participants included 23% international, and 17% completed lessons in Spanish. The majority (73%) of participants were industry professionals in production and other roles, and 71% indicated that their highest level of horticulture training was either learned on the job, or in high school. The proportion of students rating their technical knowledge in the course topics as very good to expert increased from 11% to 53% following the completion of the courses. Instructors are currently from 12 institutions, and Michigan State University (MSU) and UF have collaborated since 2022 on a "Plant Health Professional" certificate program through their combined institutions. We have a keen interest in collaborating with university and industry partners to develop a comprehensive and coordinated curriculum tailored to the needs of the industry. UF is well-positioned to assist in promoting, hosting, or translating courses, to mitigate barriers to course development and enhance accessibility for learners. Overall, the Greenhouse Training Online program has proven to be a sustainable model for bridging a gap in horticultural education, and empowering greenhouse and nursery growers with the knowledge and skills needed for success in their industry.
Speakers
NR

Nelda Raquel Hernandez Martinez

University of Florida
Co-authors
MK

Maria Kinslow

University of Florida
NA
PF

Paul Fisher

University of Florida
NA
Thursday September 26, 2024 8:45am - 9:00am HST
Kahili

8:45am HST

VCM 4 - Watermelon Cultigen Yield Response to Fusarium oxysporum f. sp. niveum Incidence in North and South Carolina, USA
Thursday September 26, 2024 8:45am - 9:00am HST
Fusarium wilt of watermelon, caused by the soilborne pathogen Fusarium oxysporum f. sp. niveum (FON), is a major disease impacting the watermelon industry. FON can severely reduce yields and is easily dispersed. Cultivar resistance is a desired control strategy due to high fungicide and grafting costs. In 2021 and 2022, triploid watermelon cultivars were evaluated at two locations (Clayton, NC and Charleston, SC) for their tolerance to FON. Eight common cultivars were evaluated for disease incidence and yield at both locations in both years. In 2022, two unreleased cultigens were also evaluated at both locations. All studies used a randomized complete block design with four replications. ‘Fascination’ grafted to ‘Carolina Strongback’ rootstock was included as a control each year. Disease incidence was measured every week starting three weeks after transplanting and until the first harvest at each location. Fruit weights and counts were taken to measure yield. In 2021, ‘Fascination’ had the lowest disease incidence at 75% in NC and ‘Embasy’ had the lowest incidence at 15% in SC. ‘Joy Ride’ had 100% incidence in NC and ‘Shoreline’ had the highest incidence in SC at 68%. Yields correlated with disease incidence with ‘Fascination’ having the highest yield of the ungrafted treatments in NC with 17,878 lb/ac (pounds per acre) and ‘Embasy’ with 22,687 lb/ac in SC. ‘Shoreline’ was the lowest yielding at both locations with 6,556 lb/ac in NC and 5,376 lb/ac in SC. The grafted ‘Fascination’ treatment had the lowest disease incidence and the highest yield at both locations in 2021. In 2022, the unreleased cultigen HMC633802 had the lowest disease incidence at both locations with 50% in NC and 51% in SC. Of the eight common cultivars, Fascination had the lowest incidence in NC at 83% and El Capitan had the lowest in SC at 52%. ‘Shoreline’ had the highest incidence at both locations with 100% in NC and 94% in SC. Yields correlated with disease incidence. Unreleased cultigen HMC633800 had the highest yield of the ungrafted treatments in NC with 15,575 lb/ac and Powerhouse had the highest yield in SC with 27,243 lb/ac. The grafted ‘Fascination’ treatment had the lowest incidence and highest yield at both locations in 2022. The cultigens we evaluated provided minimal tolerance to FON in both years.
Speakers
SM

Stuart Michel

NC State University
Co-authors
AK

Anthony Keinath

Clemson University
NA
JS

Jonathan Schultheis

North Carolina State University
Jonathan Schultheis is a Professor in the Department of Horticultural Science at North Carolina State University. He has worked exclusively with North Carolina State University for over 35 years. He research and extension work primarily involves cucurbit crops and sweetpotatoes. Key... Read More →
LQ

Lina Quesada

North Carolina State University
NA
Thursday September 26, 2024 8:45am - 9:00am HST
Coral 2

8:45am HST

VSF 3 - Enhancing Blueberry Production with Photo-Selective Devices
Thursday September 26, 2024 8:45am - 9:00am HST
Blueberries rank among the top ten agricultural commodities in Georgia, contributing 2.45% to the state's GDP, with 27,000 acres across the state and a farm gate value of $449.4 million. Blueberry plants are exposed to elevated temperatures and intense solar radiation during the growing season. This research aimed to reduce adverse environmental effects by modifying the spectral distribution of sunlight. Our team examined the application of photoselective devices Opti-Gro and ChromaGro in blueberry production in Georgia. The research experiment was conducted at two locations (Alma and Rebecca, GA) using a randomized complete block design with four treatments: T1 (Opti-Gro), T2 (ChromaGro), T3 (a commercial grow tube), and T4 (control-unprotected plant), each replicated five times. Photoselective devices positively impacted plant height, yield, total soluble solids, anthocyanins, and titratable acidity. Plants under T1 and T2 also resulted in higher net photosynthesis and stomatal conductance. In summary, the use of photoselective devices presents a promising approach to improve blueberry production in Georgia.
Speakers
AG

Amit Godara

The University of Georgia
Co-authors
AD

Angelos Deltsidis

The University of Georgia
ZR

Zilfina Rubio Ames

The University of Georgia
Thursday September 26, 2024 8:45am - 9:00am HST
South Pacific 2

9:00am HST

CE 4 - The Physiological Responses of Citrus Tree Roots to Soil Acidification
Thursday September 26, 2024 9:00am - 9:15am HST
Citrus tree roots are vital in nutrient uptake, water absorption, and overall plant health. Soil pH alters the availability and mobility of essential nutrients in the soil, thus influencing root physiological processes; like most plants, citrus trees are particularly vulnerable to changes in soil pH levels. The root apoplast is the plant component that first encounters adverse soil chemical conditions; hence, the conditions in the root apoplast determine a plant's response. This study aims to investigate the physiological responses of citrus tree roots to soil acidification, focusing on the impact of varying soil pH on root morphology, nutrient uptake, and overall root health. A controlled three-month greenhouse study was conducted at the Citrus Research and Education Center (CREC), hypothesizing that soil acidification will alter apoplast and phloem pH, reducing CLas population and root damage. This study was conducted utilizing citrus trees subjected to different soil pH levels. Forty trees were used and divided into four groups by pH treatment. These trees were irrigated thrice a week with pH treatments: 5.5, 6.5, 7.5, and 8.5. Soil acidity and alkalinity were routinely monitored with pH probe sticks. Once soil pH stabilized, feeder root samples were taken for apoplastic and phloem pH experiments. The pH-sensitive fluorescent stains were used for microscopy and vacuum infiltration to collect apoplastic fluids. Parameters such as root length, root surface area, and root diameter were measured to assess the morphological changes in citrus tree roots under different pH treatments. The concentration of essential macro- and micronutrients from the soil, plant tissue, and leachates was also analyzed weekly to evaluate nutrient uptake efficiency. Preliminary results indicate that soil acidification significantly improves fruit yield and feeder root density. By ascribing the specific mechanisms underlying root responses, this research provides valuable insights into the adaptive capabilities of citrus trees. It informs future practices to preserve the health and productivity of citrus groves.
Speakers
avatar for Duplicate Sambani

Duplicate Sambani

PhD Student, University of Florida
Co-authors
DK

Davie Kadyampakeni

University of Florida
NA
Thursday September 26, 2024 9:00am - 9:15am HST
Coral 1

9:00am HST

EcoPhys 2 - The Carbon Cost of Phosphorus Deficiency in Southern Highbush Blueberry
Thursday September 26, 2024 9:00am - 9:15am HST
Phosphorus (P) deficiency in plants causes detrimental effects on their growth and development, as P is a key macronutrient used in various physiological, biochemical and cell signaling processes. Research has shown that P-deficient plants exhibit several symptoms such as changes in leaf coloration, root morphology, and plant growth. However, many of those studies ignore gas exchange parameters. In this research, we studied the connection between P-deficiency and carbon (C) gain and loss in southern highbush blueberry (SHB, Vaccinium corymbosum interspecific hybrids) young plants to estimate the C cost of P-deficiency. The experiment was conducted using a hydroponic system where three-month old plants of ‘Farthing’ and ‘Keecrisp’ varieties grew in individual 2-L reservoirs filled with continuously-aerated complete nutrient solution containing 15 mg/L P during a 35-day acclimation period. After the acclimation period, plants were separated into two groups and continued to grow for 56 more days (treatment period). One group ( P) was grown in the complete nutrient solution, while the second group (-P) was grown in a P-free nutrient solution (0 mg/L P). We designed and tested a whole-plant gas exchange system that utilizes two infrared gas analyzers (CIRAS-3 and CIRAS-4) to simultaneously measure root system respiration and whole-plant C assimilation. Additionally, we measured root C exudation, fresh and dry mass accumulation, and P concentration and content. We induced P-deficiency as -P plants of both varieties had mature and young leaf P concentration below 0.12% (reference deficiency level). P plants had higher P concentration after treatment period. -P ‘Farthing’ plants had 89% less daily C assimilation than P plants, while no differences were observed in ‘Keecrisp’. Daily root respiration and C exudation, considered as ways of C loss, were, 3.5 and 2.9 times higher in -P than in P plants of ‘Farthing’. Similarly, -P ‘Keecrisp’ plants had 3.8 and 2.5 times more daily root respiration and C exudation compared to those under P. Ultimately, P deficiency caused a 136% reduction in daily C gain of ‘Farthing’ plants, while there were no differences between treatments in ‘Keecrisp’ plants. Our findings suggest that responses to P deficiency in SHB are genotype-specific, and that C budget and distribution in the plant play an important role in the responses to P-deficiency.
Speakers
MR

Marlon Retana-Cordero

University of Florida
Co-authors
GN

Gerardo Nunez

University of Florida
Thursday September 26, 2024 9:00am - 9:15am HST
Lehua Suite

9:00am HST

FLOR 2 - Evaluating Nighttime Application of Low Intensity LED Light Qualities to Suppress Downy Mildew Caused by Plasmopara obducens on Greenhouse Grown Impatiens
Thursday September 26, 2024 9:00am - 9:15am HST
Downy mildew (DM) of impatiens (Impatiens walleriana), caused by the oomycete, Plasmopara obducens, results in chlorosis, defoliation, and significant crop losses. Current management includes fungicides and genetic resistance. We applied photoperiodic light quality treatments to ‘Accent Premium White’ impatiens from seed sowing until flowering to limit DM and enhance plant quality. Seeds were sown in a greenhouse with a day and night greenhouse air temperature set point of 23 °C and a target daily light integral of 12 mol·m–2·d–1. A truncated 9-h short-day (SD) photoperiod was achieved by opening and closing opaque black cloth over individual greenhouse benches. Supplemental light-emitting diode (LED) fixtures provided 120 µmol·m–2·s–1 at plant height. Each bench was randomly assigned to one of nine discreet photoperiod treatments: 9-h SD (control) or 9-h SD extended by continuous 7-h LED fixtures emitting blue (405 nm), blue (445 nm), green (525 nm), red (660 nm), far-red (730 nm), white fixtures provided 100-nm waveband ratio (%) of 18:38:41:3 blue:green:red:far-red radiation, a screw-in LED flowering lamps provided 100-nm waveband ratio (%) of 7.6:15:72.4:5. Additionally, 6-h intermittent (1900 to 2200 HR and 0300 to 0600 HR) LED fixtures emitting ultraviolet-A (385 nm) were assigned to one bench. The total photon flux density was adjusted to 20 µmol·m–2·s–1 at plant height under black out curtains for each treatment. Impatiens were inoculated 70 days post sowing with a P. obducens sporangial suspension (2.6 to 3 x 105 sporangia·mL–1) until runoff on the abaxial side of the leaves. Afterwards, each plant was placed in a clear plastic bag containing 300 mL of Hoagland Solution (50%) and returned to its respective treatment. After 9-10 days post inoculation, the ratio of diseased leaves to the total leaf number was determined. In the initial experimental trial, control plants exposed to a 9-h SD treatment displayed an average disease incidence of 72.7%, while other treatment groups ranged from 30.6 to 98.3%. In the subsequent trial, control plants exposed to the same 9-hr SD treatment showed an average disease incidence of 42.6%, while other treatment groups ranged from 0 to 59.5%.
Speakers
avatar for River Dean

River Dean

Graduate Research Assistant, Michigan State Univeristy
My research is focused on environmental control strategies to limit losses from greenhouse pathogens on culinary herbs and bedding plants. 
Co-authors
MH

Mary Hausbeck

Michigan State University
NA
RL

Roberto Lopez

Michigan State University
NA
Thursday September 26, 2024 9:00am - 9:15am HST
South Pacific 3

9:00am HST

O/LT 2 - Understanding Hernando County Residents' Perspectives on Fertilizer Use and Regulations
Thursday September 26, 2024 9:00am - 9:15am HST
In response to recent revisions to the fertilizer ordinance in Hernando County, our research endeavors to delve into the attitudes and behaviors of residents towards fertilizer usage. With over 100 counties and municipalities in Florida implementing urban landscape fertilizer ordinances, Hernando County serves as a significant case study in understanding the dynamics of public perception and compliance. Our project employs a multi-faceted approach to gather comprehensive insights into resident perspectives. Tailored surveys have been developed to assess various aspects, including residents' knowledge of lawn care, familiarity with the county's fertilizer ordinances, current landscape conditions, and practices regarding fertilizer application. These surveys are being disseminated through diverse channels, encompassing social media platforms, the Hernando Extension networks, and Hernando County Utilities Department customers. Additionally, forthcoming focus group interviews will provide qualitative insights, offering a deeper understanding of community sentiments and the underlying factors shaping attitudes and behaviors. Through the integration of quantitative and qualitative data analysis, our aim is to gain a holistic understanding of the landscape of fertilizer usage in Hernando County. This entails not only identifying prevalent practices but also discerning the concerns and barriers faced by residents in adhering to the fertilizer ordinances. Such insights are pivotal in informing the development of targeted educational materials aimed at addressing community concerns, dispelling misconceptions, and providing practical guidance on responsible fertilizer usage. Our initial online survey revealed that 31% considered themselves very familiar with the Hernando County Fertilizer Ordinance, but 31% were not familiar with the details at all (n=383). Of these respondents, 73% care for their lawn and landscape themselves, with 11% using a professional service. Most residents responded that their lawn was fertilized at least once per year, with 18% saying that their lawn was never fertilized (n=844). Ultimately, the findings of our research hold significance beyond Hernando County, offering valuable lessons and strategies for promoting sustainable landscape management practices in similar contexts across Florida and potentially beyond. By fostering greater awareness, understanding, and knowledge of proper fertilizing practices, our project contributes to the broader goal of safeguarding water quality and environmental integrity for present and future generations.
Speakers
WL

William Lester

Dr., University of Florida/IFAS Extension
Co-authors
HK

Hayk Khachatryan

University of Florida Institute of Food and Agricultural Science (UF/IFAS) Mid-Florida Research and Education Center
NA
YZ

Yilin Zhuang

University of Florida
YJ

Younghyeon Jeon

1University of Florida Institute of Food and Agricultural Science (UF/IFAS) Mid-Florida Research and Education Center
NA
Thursday September 26, 2024 9:00am - 9:15am HST
South Pacific 1

9:00am HST

OPB 1 - Induction and Characterization of Mutations Related to Dwarf Habit in Hardy Hibiscus (Muenchhusia section)
Thursday September 26, 2024 9:00am - 9:15am HST
Hybrids originating from different species within the Muenchhusia section of Hibiscus are well-received in commercial markets for their vibrant and abundant blossoms. However, many commercially available varieties prove overly robust for smaller garden spaces, often yielding a limited number of blooming flowers. The cultivation of stable, heritable mutants displaying a dwarf stature and improved branching architecture holds significant promise for enhancing the commercial production of resilient Hibiscus. The objective of this project was to induce point mutations in genes linked to the biosynthesis or signaling of plant growth-related hormones, using ethyl methanesulfonate (EMS). Successful induction of multiple mutations associated with dwarf, compact phenotypes was achieved. Hybridizations were carried out between M2 plants exhibiting a dwarf phenotype and hybrids generated through traditional breeding that lacked the dwarf mutation in their genetic background. This aimed to produce a diverse array of dwarf plant selections. The inheritance patterns of the dwarf genes were elucidated by analyzing the segregation ratios of the dwarf phenotype in the F1 and F2 generations of these hybrids. In comparison to non-dwarf progeny, dwarf progeny exhibited significantly shorter internode lengths and a greater number of primary branches.
Speakers
CA

Conner Austin

University of Florida
Thursday September 26, 2024 9:00am - 9:15am HST
South Pacific 4

9:00am HST

PH 3 - Apple Ripening After DCA Storage: Assessing The Risk Of Flavor Loss
Thursday September 26, 2024 9:00am - 9:15am HST
Dynamic controlled atmosphere (DCA) storage suppresses the ripening of apple fruit during storage to a greater extent than standard CA storage. DCA is a relatively new technology, and it has the potential to markedly alter the volatile profile of apple fruit. It has been found that DCA storage can suppress the most important aroma volatiles of stored apple fruit. What we don't know is the length of time and the conditions needed to recover that loss in aroma, especially when DCA is applied in combination with the ethylene action inhibitor 1-methylcyclopropene (1-MCP). A critical concern about 1-MCP is that apple flavor is compromised in treated fruit because aroma volatiles are so closely linked with ethylene response. Apple fruit from high-value cultivars were stored under a DCA regimen (approximately 0.4% O2), with and without 1-MCP treatment, for 3, 6, and 9 months. Following removal of fruit from DCA, the volatile profile and fruit quality traits were measured for up to 5 weeks while being held at room temperature. The recovery of aroma formation following storage for 6 months was essentially immediate for ‘Red Delicious’ fruit if 1-MCP was not used. The recovery was a little slower for one of the replicate studies if DCA was used. If the fruit were treated with 1-MCP, there was a 2-week delay in the recovery of aroma formation. ‘Evercrisp’ aroma formation was much lower than ‘Red Delicious’ and the responses to DCA and 1-MCP differed from that of Red Delicious. Aroma formation remained very low for 3 to 4 weeks at room temperature following CA and DCA storage and never recovered following 1-MCP treatment for the 5-week duration of the study. The data for aroma formation after 9 months was similar to that at the 6-month time point for ‘Red Delicious’ in terms of 1-MCP responses. However, the effect of DCA seemed to be more pronounced, suppressing aroma recovery for an additional week at room temperature. For ‘Evercrisp’, the 9-month data were quite similar to those from 6 months storage.
Speakers
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Co-authors
JX

Jiarui Xu

Michigan State University
NA
NS

Nobuko Sugimoto

Michigan State University
NA
OH

Ozge Horzum

Ankara University
NA
Thursday September 26, 2024 9:00am - 9:15am HST
Nautilus 1

9:00am HST

TCHG 2 - Invasive Species Education in Florida: Insights from a Yearlong Webinar Pilot Program
Thursday September 26, 2024 9:00am - 9:15am HST
Invasive species pose significant threats including economic losses in agriculture and horticulture, decreased biodiversity, human and animal health hazards, disruption of native ecosystems, and more. In the U.S., the losses due to invasive species were historically estimated at around $120 billion annually, but a more recent study suggests this cost is much higher at $1.2 trillion. Florida is a high-risk state for the introduction and establishment of invasive species due to the state’s diversity of agricultural commodities, mild winters, large number of international deep-water ports and airports, and highly desirable tourism operations. Research shows that the public plays an important role in early detection of invasive species, but awareness is critical to the development of strong volunteer-based networks. Licensed pesticide applicators, often the first to observe suspicious pests, play a crucial role in both early detection and ongoing management of non-native species in Florida. To address these challenges, the First Fridays with Florida First Detector webinar program was developed. This yearlong pilot program offered one-hour lunch time webinars on the first Friday of every month beginning in September 2022. Leveraging innovative online education techniques, the program aimed to connect diverse professional and public audiences across Florida. Due to the interdisciplinary nature of invasive species issues, webinars engaged multiple stakeholder groups including farmers, horticultural professionals, landscapers, land managers, master gardener volunteers, homeowners, and beyond. The content focused on increasing knowledge about invasive species, including the identification of species not yet detected and recently introduced species in Florida. The goals were to promote early detection of new species, monitor the spread of recently introduced species, and offer sustainable management recommendations for species currently impacting Florida. Each month highlighted a different pest group including invasive fruit flies, palm pests, wood boring insects, citrus pests, snails, and more. Post-reflective surveys demonstrated that 94.7% (n=675) of respondents increased their knowledge on invasive species and 99.9% intended to adopt at least one practice learned. Six-month follow up surveys, evaluating behavior implementation over time, showed that 97.5% (n=166) of respondents had adopted at least one practice (i.e. submitted samples of suspicious pests, employed integrated pest management, etc.) since attending a webinar. The findings underscore the effectiveness of interdisciplinary, collaborative approaches in addressing invasive species challenges. This presentation will discuss the methodologies and experiences in developing and implementing the one-year pilot program as well as the program’s future directions and potential applicability to other regions.
Speakers
MP

Morgan Pinkerton

Sustainable Agriculture and Food Systems Agent, UF/IFAS Extension Seminole County
Co-authors
AH

Amanda Hodges

University of Florida
NA
KM

Kaydie McCormick

UF/IFAS Extension Seminole County
Thursday September 26, 2024 9:00am - 9:15am HST
Kahili

9:00am HST

VCM 4 - Effect of Biostimulants on Field Grown Watermelon (Citrullus lanatus) under Deficit Irrigation and Fertility.
Thursday September 26, 2024 9:00am - 9:15am HST
The impacts of climate change and drought threaten water supplies crucial for watermelon production. Rising fertilizer costs and off-site effects also pose problems for the sustainability of watermelon production. Biostimulants shown promise in helping plants maintain production under deficit irrigation conditions and may offset fertility addition through ecosystem services and stimulatory effects. In this study two watermelon cultivars (Crimson Sweet and Fascination) were treated with three biostimulant products (Mighty Mycorrhizae, Spectrum DS, and Continuum) and then subjected to reduced fertility (67% of recommended rate) and irrigation (75% evapotranspiration). Raised beds covered in plastic mulch were used with rows spaced 1.83 meters apart and plants 0.61 meters apart within rows. Growth metrics and stages were recorded and compared among treatments. Watermelon fruits were harvested at maturity over a one-week period and yield was compared. The final biomass was measured after harvest. Statistical analysis is ongoing, and a second year of this field trial will be completed in August 2024, allowing for final conclusions to be drawn.
Speakers
EC

Evan Christensen

Utah State University
Co-authors
DD

Dan Drost

Utah State University
NA
YS

Youping Sun

Utah State University
Thursday September 26, 2024 9:00am - 9:15am HST
Coral 2

9:00am HST

VSF 3 - Modeling Production Curves of Southern Highbush Blueberry for Improved Productivity and Efficient Harvestability
Thursday September 26, 2024 9:00am - 9:15am HST
Agronomic crops have their yield potential assessed once per growing season at harvest time. In contrast, horticultural crops such as blueberries (Vaccinium spp.) require prolonged harvest periods, spanning 6 to 8 weeks of recurrent mechanical- or hand-picking. Collected data throughout the harvest period offer a comprehensive source of information to estimate production curves (cumulative harvest). These capture the yield dynamics of each cultivar under specific environmental conditions and treatments. For blueberry growers in Florida, desirable production curves should exhibit: 1) accumulation at the beginning of the harvest season (earliness), and 2) reduced harvest periods (concentration). This pattern is advantageous as it could significantly enhance productivity and profitability while simultaneously cutting down labor costs linked to harvest operations. Thus, pinpointing cultivars displaying these beneficial traits is paramount. In this study, we considered the Weibull distribution to model the production curves for each genotype-in-environment combination. Phenotypic and genomic information were combined for model calibration to predict the corresponding parameters of the distribution besides yield performance in a multi-trait framework. To our knowledge, there are no methods in the current literature that address the identification of cultivars that both ripen early and/or are suited for concentrated harvesting. In this study, we employ a novel analytical approach designed to fill this gap, aiming to systematically identify cultivars aligning with these ideal production characteristics.
Speakers
JM

J. Martin Zapien-Macias

PhD Student, University of Florida
Co-authors
DJ

Diego Jarquin

University of Florida
GH

Gerardo H. Nunez

University of Florida
Thursday September 26, 2024 9:00am - 9:15am HST
South Pacific 2

9:15am HST

CE 4 - Towards Sustainable Controlled Environment Agriculture Systems: Developing An Intelligent Decision-Making Tool For Impro
Thursday September 26, 2024 9:15am - 9:30am HST
Controlled Environment Agriculture (CEA) systems significantly enhance crop yields per unit area in comparison to traditional open-field farming methods. Moreover, they contribute to reduced water consumption and offer extended and more predictable growing seasons. While CEA systems show promise in meeting urban vegetable demand, the question remains what the required inputs are (water, fertilizer, energy, labor) for different systems (vertical farm, greenhouses) in different climate locations. In this work, an easy-to-use transient energy model that simulates the internal microclimate of CEA systems is developed. The microclimate will include changes in temperature, humidity, water, nutrient, and carbon dioxide while also computing the energy costs associated with conditioning the space and electricity. This model will also accurately map the leaf temperature and hence compute the transpiration water loss accounting for the spectra of different artificial light sources. The energy model will be linked to a functional crop growth model that can simulate the yield of the plant over multiple growth cycles and quantify water and nutrient uptake. The potential of the developed model is demonstrated by performing simulations of year-around greenhouse operation within the U.S. Two climates categorized into hot, and cold based on annual temperature are selected for the simulation of tomato production. Results indicate that supplemental lighting energy requirement ranged between 128-160 kWh/m2-year across the selected climate zones to achieve target yield in a given duration. Overall energy consumption ranges from 200 - 400 kWh/m2-year. Overall, the supplemental lighting requirement makes upto 75 percent of the total required DLI and provides comparable improvements in biomass compared to yield in greenhouses without supplemental lighting. Finally, the model indicates that upto 90 percent of total supplemental lighting requirements require light intensities in the combination of 250 and 500 µmoles m-2 s-1 to satisfy the additional DLI requirement. However, a higher lighting intensity of 1000 µmoles m-2 s-1 is required sporadically at night during winter between October – March in the northern latitudes. Overall, this model integrates energy, temperature, nutrition, and crop yield considerations for various crops and acts as a useful predictive tool for assessing operational costs based on target yield and duration of growth for greenhouses operating in any given climate.
Speakers
ER

Eshwar Ravishankar

Assistant Professor, Cal Poly Pomona
Co-authors
LS

Lahari Sandepudi

Cal Poly Pomona
NA
RH

Ricardo Hernandez

North Carolina State University
NA
Thursday September 26, 2024 9:15am - 9:30am HST
Coral 1

9:15am HST

EcoPhys 2 - Intra- and Inter-Annual Changes in Soil Health with Native Plant Monocultures
Thursday September 26, 2024 9:15am - 9:30am HST
The interactions between plants and their soil environment influence overall soil system health. Soil provides plants with the structural support, water, nutrients, and microbial interactions they need for creating biomass and for reproduction. Conventional agriculture practices degrade soil; however, small plots of native plants within agricultural settings have been shown to provide disproportionally large benefits to both ecological and agricultural landscapes. In other words, even small plots of native plants can improve soil health. Although small plots of mixed native plant species improve soil health, they offer little in the way of income opportunities for producers through seed collection and sales. However, plots of native monocultures may offer producers an opportunity to harvest and sell seeds, taking advantage of the increasing demands of the native seed market while also increasing soil health. Therefore, this study's objective is to quantify the effects of small native plant monocultures on soil health and compare them to soil health from conventional crop plots. We investigated biological indicators of soil health such as organic matter, organic carbon, and microbial communities as well as abiotic indicators like nutrient composition. We hypothesize that, compared to crop plots, native monoculture plots will have more microbial diversity and higher amounts of soil nutrients. We tested our hypothesis by comparing soil health characteristics from plots containing five established native monocultures: Dalea candida, Agastache nepetoides, Glycyrrhiza lepidota, Liatris ligulistylis, and Tradescantia occidentalis; and one crop plot planted with a corn and soybean rotation. During the second and third season of growth, monthly soil samples were taken, and soil indicator values were compared using Tukey’s HSD post hoc tests after performing an analysis of variance (ANOVA). Results suggest that native plant species influenced soil health differently than crop rotations after three seasons of growth. Compared to crop plots, soil samples from two species of native plants, Agastache nepetoides and Tradescantia occidentalis, had higher fungi-to-bacteria ratios (p = 0.0160 and p < 0.0001, respectively), and higher amounts of saprophyte biomass (p = 0.0040 and p = 0.0484, respectively). Soils from the Agastache nepetoides plots also had higher amounts of Pre18 cyclo fatty acids (p = 0.0022) and potassium (p = 0.0159). These two species of native plants show potential for improving soil health after three years of establishment. Adding these two native monocultures to marginal production land may add soil health benefits during early establishment periods while providing a marketable crop for producers.
Speakers
BL

Bret Lang

Student, South Dakota State University
Co-authors
LP

Lora Perkins

South Dakota State University
NA
Thursday September 26, 2024 9:15am - 9:30am HST
Lehua Suite

9:15am HST

FLOR 2 - Supplemental Day-Extension Lighting Influences Rooted Cutting Growth and Quality of Finished Annual Bedding Plants
Thursday September 26, 2024 9:15am - 9:30am HST
Floriculture makes up the largest sector of ornamental horticulture production, valued at $6.7 billion and dominated by the production of annual bedding-plants. Production is timed to meet spring market dates, starting during a time of year when ambient outdoor temperatures and daily light integrals are below optimal for high-quality plant production. As a result, heating and supplemental lighting can represent a significant operational and energy cost for producers. Yet, producers and investors of the industry have acknowledged an inability to evaluate their resource use due to a lack of industry-wide benchmarks and key performance indicators (KPIs). Past research has compiled energy and water data from controlled environment agriculture (CEA) and, for floriculture, investigated the potential of energy-efficient production strategies and used life cycle assessments (LCAs) to evaluate the environmental impact of the products produced. However, CEA focuses on food production and both the compiled CEA data and the LCAs are largely based off modeled data. Therefore, this research will validate models utilized in LCAs and carbon footprint studies with experimental data, giving producers additional benchmarks and KPIs to evaluate their operational resource-use efficiency. The objectives of this study were to (1) evaluate the use of supplemental day-extension lighting (SDEL) from two different fixtures [(light-emitting diodes (LEDs) and high-pressure sodium (HPS)] during unrooted cutting (URC) propagation of five annual bedding plants and (2) to quantify the greenhouse energy and water consumption. Unrooted cuttings were received from a commercial propagator and stuck in a 105- (calibrachoa, coleus, impatiens, and petunia) or 72- (geranium) propagation tray filled with a pre-moistened soilless propagation substrate and placed under oner of three SDEL treatments on root-zone heating set to 23℃. Each treatment consisted of a propagation tent for callusing and an adjacent rooting environment. Until adventitious root formation, cuttings were misted with clear water, and then were removed from the propagation tent where they were irrigated daily with 150 mg·L–1 nitrogen provided by 15-5-15 water-soluble fertilizer (JR Peters, Inc.; Allentown, PA). After 21 days, data were collected on rooted cuttings. As expected, the energy-use of HPS-lamps exceed that of the LEDs. However, cutting stem-length and stem and leaf dry mass were decreased under SDEL, resulting in liners that were more compact, uniform, and of higher quality than those propagated under ambient conditions. An opposite trend was observed for root dry mass. This indicates that SDEL is a critical tool when utilized for bedding-plant propagation.
Speakers
LS

Lauren Seltsam

The Ohio Sate University,
Co-authors
GO

Garrett Owen

The Ohio State University
Thursday September 26, 2024 9:15am - 9:30am HST
South Pacific 3

9:15am HST

O/LT 2 - Using Different Ratios of Blue and Red Light to Induce Drought Tolerance Morphology in Zinnia
Thursday September 26, 2024 9:15am - 9:30am HST
Growing population, rapid urbanization and economic expansion have been raising the demand for fresh water. Additionally, climate changes, characterized by warmer temperatures, shifting precipitation patterns, and reduced snowpack are diminishing the water availability presenting new challenges for agricultural water use and conservation, particularly in the arid western states. One approach to addressing water scarcity involves inducing drought tolerance in crops. Plants exhibit physiological, morphological, and biochemical changes upon exposure to different wavelengths of light. This study focuses on determining the optimal ratio of blue to red light for inducing drought tolerance morphology in Zinnia elegans ‘Envy’. Seeds were sowed in Metro-Mix® 820 (SunGro Horticulture, Agawam, MA, USA) and kept on a misting bench. After germination, the plugs were exposed to full spectrum LED grow lights (ScynceLED, Mesa, Arizona) maintained at three ratios of blue and red light, 10:90, 25:75, and 50:50, controlled using a spectrometer (StellarNet Inc., Tampa, Florida, USA) in a covered chamber. The Photosynthetic photon flux density (PPFD) was maintained at 150 µmol.m-2.s-1 and the photoperiod was maintained at 12 hour dark and 12 hour light period. After four weeks of treatment, physiological and morphological parameters were measured in five destructively harvested plugs per treatment. The leaf number, growth index, and leaf area index showed no significant differences among treatments, however, the rate of assimilation and stomatal conductance were found highest under the 50:50 blue and red light ratio, compared to 25:75 but similar to 10:90. The total dry weight, leaf thickness, SPAD, and NDVI values were also higher at the 50:50 ratio, with total dry weight comparable to the 25:75 ratio. Subsequent irrigation treatments at 25% and 35% volumetric water content (VWC) were applied with the help of automated irrigation system using capacitance sensor, ECH2O 10HS (Meter Group, Pullman, WA, USA) to assess water requirements under different ratios of blue and red light suggesting a potential of these light treatments to reduce the Zinnia’s water needs.
Speakers
AC

Anju Chaudhary

Utah State University
Co-authors
SP

Shital Poudyal

Utah State University
NA
Thursday September 26, 2024 9:15am - 9:30am HST
South Pacific 1

9:15am HST

OPB 1 - Compatibility of Cross-hybridizing Lagerstroemia taxa
Thursday September 26, 2024 9:15am - 9:30am HST
Lagerstroemia indica L. is a favored landscape plant in mild-climate regions, cherished for its easy propagation and cultivation, prolonged blooming period, and variety of plant forms. The majority of new cultivars are the result of cross hybridization. However, compatibility issues arise with some cultivars and species. To enhance our understanding of the cross-compatibility of our elite cultivars, we selected four plants (C14-35, C14-39, D03-29, and D03-34) for reciprocal crosses and for crossing with other elite plants, chosen for their clean foliage and extended summer bloom periods. A total of 3126 crosses were made in the summer of 2023. By the season's end, 731 fruits were harvested to assess seed set, and viable seeds were counted in winter 2023. From these efforts, 20,862 seeds were harvested, with 5,470 identified as viable. Interspecific crosses with L. speciosa revealed that C14-35 and C14-39 had significantly better fruit set percentages (40% and 35.2%, respectively) compared to D03-29 and D03-34 (6.3% and 0%, respectively). Thus, C14-35 and C14-39 exhibit greater compatibility with L. speciosa. For reciprocal crosses, C14-39 and D03-34, when used as pollen donors, resulted in much lower fruit set percentages and seed sets than C14-35 and D03-29. Pollen studies of the four cultivars indicated that both C14-39 and D03-34 produced little to no pollen, while C14-35 and D03-29 were prolific pollen producers. Future cross hybridization studies will therefore avoid using C14-39 and D03-34 as pollen donors. A seed germination study is planned for spring 2024 to further assess the various cross combinations and confirm interspecific hybrids.
Speakers
YY

Yongjun Yue

University of Georgia
Co-authors
DZ

Donglin Zhang

University of Georgia
Thursday September 26, 2024 9:15am - 9:30am HST
South Pacific 4

9:15am HST

PH 3 - The Impact Of Hot Water Treatment On Organic Apple Quality With Different Storage Systems
Thursday September 26, 2024 9:15am - 9:30am HST
There has been a surge in demand for organic apples in the U.S. in the last decade. Washington State supplies more than 90% of them because of the ideal climate and soil conditions that favor production. Thermotherapy methods are widely used in Europe to reduce postharvest rots, but they have not been adopted in the U.S. because of their potential detrimental effects on fruit quality. The objective of this research was to evaluate the impact of hot water treatments at harvest on fruit quality during long-term storage. ‘Royal Gala’ and ‘Honeycrisp’ apples were immersed at 49 °C or 52 °C for 2 minutes in a controlled hot water bath immediately after harvest. After fruits were dried at 20 °C, they were placed in controlled atmosphere (CA; 2 kPa O2, 0.5 kPa CO2, 1°C-‘Royal Gala’, 3oC-‘Honeycrisp’) and air (RA; 1°C-‘Royal Gala’, 3oC-‘Honeycrisp’) storage for up to 9 months. Fruit quality (firmness and titratable acidity), defects, and physiological disorders were evaluated 1 and 7 days at 20 °C. In general, ‘Royal Gala’ apples immersed at 49 °C and stored in CA had no decay after 3 and 6 months of storage, but it was the highest (around 9%) in ‘Honeycrisp’ in both CA and RA. Peel damage was less at 49 °C for both ‘Royal Gala’ (RA-1.3%; CA-5%) and ‘Honeycrisp’ (RA-7.4%; CA-2.8%) compared to 52 °C after 3 months. Fruit firmness and titratable acidity were statistically different (p≤0.05) at 49 °C compared to 52 °C after 3 months. Although the hot water treatment in ‘Royal Gala’ apples was effective in reducing decay incidence without compromising fruit quality, the opposite was found in ‘Honeycrisp’; therefore, further research is needed to confirm these results and understand the variety-dependent effect.
Speakers
avatar for Sadat Amankona

Sadat Amankona

Washington State University-TFREC
I am a second-year Ph.D student at Washington State University (Tree Fruit Research & Extension Center). My research is about using non-chemical solutions for long-term storage of organic apples.
Co-authors
CT

Carolina Torres

Washington State University
Thursday September 26, 2024 9:15am - 9:30am HST
Nautilus 1

9:15am HST

TCHG 2 - Closing the Gap: Developing Greater Awareness of Horticulture Careers in Controlled Environment Agriculture in Secondary Schools
Thursday September 26, 2024 9:15am - 9:30am HST
In today's high schools, students are often unaware of the diverse and meaningful careers available in horticulture, especially within controlled environment agriculture (CEA). From machine learning to design engineering, CEA encompasses a wide range of technical fields, yet these opportunities are frequently overlooked in state-led agriculture curricula. This presentation underscores the need for improved national communication among agriculture teachers to develop effective programs that educate students about the rich array of horticulture careers. We advocate for the creation of equipment and curriculum that vividly depict these career paths. Furthermore, there's a pressing need to expand students' awareness of post-secondary education options beyond state boundaries. While careers in medicine are well-known, horticulture careers, which are equally complex and rewarding, often go unnoticed by technically-minded students. As the demand for locally-produced, sustainable food rises, the need for skilled horticulturists in every niche grows. We urge for a greater influx of horticulture students to meet this demand and drive innovation in the field. In summary, this presentation highlights the urgency of bridging the gap between students and the myriad opportunities available in horticulture, particularly within the dynamic realm of controlled environment agriculture.
Speakers
MY

Melanie Yelton

GrowBig Consulting
Melanie Yelton, Dr. Yelton leverages over 25 years of plant science leadership to guide controlled agriculture entities towards climatically resilient food systems. Via her consultancy company, GrowBig, she advises controlled environment agriculture farms, lighting partners and R... Read More →
Co-authors
EW

Eli Weissman

GrowBig Consulting
NA
Thursday September 26, 2024 9:15am - 9:30am HST
Kahili

9:15am HST

VCM 4 - Development of the winter artichoke production system in a subtropical climate
Thursday September 26, 2024 9:15am - 9:30am HST
Artichoke (Cynara cardunculus var. scolymus) belongs to the sunflower family and is cultivated for its flower buds. Being adapted to Mediterranean climates, artichoke plants require adequate winter chilling for flower bud induction and yet is susceptible to freeze damage. Because of these climatic requirements, nearly 100% of artichoke production in the United States currently comes from California. Insufficient winter chilling is among the major environmental constraints for artichoke production in subtropical and tropical climates. We started this study in 2015 with the goal of developing artichoke as a new winter crop in Florida. First, we developed a protocol for artificial flower bud induction using a plant hormone, gibberellic acid (GA3). With the optimum rate and timing, GA3 application is highly effective in inducing bud formation, irrespective of winter chilling. Second, we evaluated eight cultivars based on earliness of bud formation, yield, and bud quality. ‘Imperial Star’ and ‘Green Queen’ were selected as the most promising cultivars in Florida, with the maximum yields of 17.3 and 11.8 t ha–1, respectively. The current artichoke production guide provides recommendations on GA3 application, cultivars, planting configurations, plastic mulch, and basic pest management. In 2023, artichoke was grown on about 12 hectares in Florida using the production guide we developed. We are currently testing additional hybrid cultivars and assessing nutritional values and postharvest quality to enhance the viability of artichoke as Florida’s new winter crop.
Speakers
SA

Shinsuke Agehara

University of Florida
Co-authors
WW

Weining Wang

University of Florida
Thursday September 26, 2024 9:15am - 9:30am HST
Coral 2

9:30am HST

CE 4 - Global Sensitivity Analysis and Validation of the Modified Energy Cascade Crop Model for Controlled Environment Agricult
Thursday September 26, 2024 9:30am - 9:45am HST
The Modified Energy Cascade (MEC) crop model was originally developed to predict the edible biomass production of bioregenerative life support systems (BLSS) along with BLSS consumption and production of O2 and CO2. Three distinct MEC versions support this original goal and controlled environment agriculture (CEA) on Earth. Cavazzoni built the first MEC for predicting crop growth, transpiration, and productivity of BLSS. Boscheri et al. and Amitrano et al. each developed versions building off Cavazzoni's work. While each of these model versions builds off each other, differences in methodology and assumptions of plant physiology impact the outputs of the model, necessitating a comparison between versions. To describe the effects of input variability and model structure on the outputs of the MEC versions before further development for BLSS and CEA production facilities, four research questions were chosen to guide this evaluation. 1) How much variation in transpiration and yield predictions can be attributed to the model version? 2) How are input variations propagated through the cascading nature of the models? 3) Which model components are highly sensitive or uncertain to which environmental conditions? 4) How well does each model version predict the outcome of lettuce yield and transpiration outcomes of data sets independent from model development? To answer the first three questions, a series of global sensitivity and uncertainty analyses were performed. They revealed that 1) for daily transpiration rate and edible biomass model version alone can explain between 69% and 82% with Amitranos representing the lowest values and Boscheris the highest typically. 2) Even in sequences of identical equations, where each subsequent calculation is identical, variability is gradually reduced with final output variations between 40% - 55% that can be attributed to the prior upstream differences. 3) The Cavazzoni and Boscheri edible yield predictions are highly sensitive to photosynthetic photon flux density (PPFD) and CO2 across calculations while Amitrano’s is more responsive to photoperiod rather than PPFD. 95% of Boscheris transpiration output is driven by relative humidity while the other two utilize a combination of that and photoperiod. Lastly, these models and their performance were evaluated using environmental and yield data from an indoor vertical farming facility and growth chamber experiments. Together these analyses provide the information necessary to continue the development of the MEC for the prediction of resource flows and yield of CEA and BLSS supporting the optimization of electricity usage and circularity processes within closed-loop agriculture.
Speakers
DC

Donald Coon

University of Florida
NA
Co-authors
AM

Ana Martin Ryals

University of Florida
CA

Chiara Amitrano

University of Naple
NA
GN

Gerardo Nunez

University of Florida
MC

Melanie Correll

University of Florida
NA
RC

Rafael Carpena

University of Florida
NA
YZ

Ying Zhang

University of Florida
ZB

Ziynet Boz

University of Florida
NA
Thursday September 26, 2024 9:30am - 9:45am HST
Coral 1

9:30am HST

FLOR 2 - Daily Light Integral Influences Adventitious Rooting of Achillea Cuttings
Thursday September 26, 2024 9:30am - 9:45am HST
Rooting of herbaceous perennial cuttings occurs year-round in greenhouses under photosynthetic daily light integrals (DLIs) ranging from ≈1–20 mol·m–2·d–1. The effects of DLI on rooting and cutting growth have not been quantified for many vegetatively propagated herbaceous perennials. As such, our objectives were to determine the effects of DLI on adventitious rooting and cutting quality of a popular herbaceous perennial, yarrow (Achillea sp.). Unrooted cuttings of yarrow (Achillea millefolium ‘Apricot Delight’) were received from a commercial cutting supplier and callused in a glass-glazed greenhouse for 5 d under ≈3.6 mol·m–2·d–1 at 24 °C root-zone and air temperatures. Upon callusing, cuttings were transferred to a rooting environment with 21 °C air temperature and 24 °C root-zone temperature set points. Cuttings were rooted under one of four different fixed-woven shadecloth providing ≈86%, 62%, or 26% shade or no shade (0%) thereby establishing mean DLIs ranging from 1.6 to 15.2 mol∙m‒2∙d‒1. Cutting growth and biomass accumulation evaluations were made 8, 11, and 14 d after transfer. In general, yarrow stem caliper, stem length, and leaf number were unaffected by increasing DLI; however, leaf, stem, root, and total biomass accumulation increased with increasing DLI though to different magnitudes. For example, as DLI increased from 1.6 to 15.2 mol∙m‒2∙d‒1, leaf, stem, root, and total biomass accumulation increased by 84%, 85%, 458%, and 93% at 8 days after transfer to 98%, 110%, 893%, and 128% at 14 days after transfer, respectively. When taken together, DLI should be properly managed to hasten and improve rooting and growth of yarrow cuttings during adventitious root development.
Speakers
avatar for Garrett Owen

Garrett Owen

Extension Specialist and Assistant Professor of Sustainable Greenhouse & Nursery Systems, The Ohio State University
Dr. W. Garrett Owen is Assistant Professor and Extension Specialist of Sustainable Greenhouse and Nursery Production Systems with primary responsibilities in teaching (20%), research (30%), and Extension (50%) in the Department of Horticulture and Crop Science at The Ohio State University... Read More →
Co-authors
RL

Roberto Lopez

Michigan State University
NA
Thursday September 26, 2024 9:30am - 9:45am HST
South Pacific 3

9:30am HST

O/LT 2 - Techniques to Improve Growth, Heat, and Drought Tolerance in Container Grown Trees
Thursday September 26, 2024 9:30am - 9:45am HST
Heat and moisture stress are increasing limitations to production of container-grown trees and growth of landscape trees, while reducing water use is an increasingly common goal. In two experiments, we investigated methods for reducing stress caused by limited water and extreme heat in container-grown tree seedlings in Aurora, Oregon. In the first experiment, we evaluated the potential for several ‘biostimulant’ or stress-tolerance inducing, soil-applied materials to improve growth of tree seedlings (Betula nigra) under limited water conditions. In the second experiment, we evaluated one of the most promising materials from that study in comparison to several other known or potential stress-reducing materials or techniques. In the first study, B. nigra seedlings were grown in pots with full water (determined by site evapotranspiration rate), one-half water, or one-half water with four different commercially available ‘biostimulant’ products that are marketed as inducing tolerance to moisture and heat stress in plants. Caliper growth, visual rating, and chlorophyll fluorescence values all showed that in the low-water groups, the plants treated with a mannitol plus calcium chelate product or a potassium phosphite product performed best and significantly better than the low-water control group. In the second experiment, over the course of two seasons we compared the effects of soil-applied potassium phosphite with other methods previously shown to reduce heat and/or drought stress. Abnormal extreme heat events, or ‘heat domes’, occurred during both growing seasons. Container-grown red maple (Acer rubrum) saplings were grown with moderate water and subjected to one of six treatments: untreated control, fresh-water misters triggered by preset ET value, kaolin foliar treatment, potassium phosphite soil application, propiconazole foliar treatment, and paclobutrazol foliar treatment. After two growing seasons, the mist treatment significantly improved growth compared to control plants while the potassium phosphite and kaolin treatments showed non-significant trends of improved growth. Based on these two studies, it is concluded that where possible, mist treatments during hot and dry conditions can improve container-grown tree seedling growth and condition, while potassium phosphite soil treatment and kaolin foliar treatments are likely to improve growth and condition in landscapes or where installation of misting apparatus is not feasible.
Speakers
DZ

Drew Zwart

Plant Pathologist & Physiologist, Bartlett Tree Research Labs
Co-authors
LN

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
Thursday September 26, 2024 9:30am - 9:45am HST
South Pacific 1

9:30am HST

PH 3 - Fungicides and Scald Inhibitor Diphenylamine Shift Microbiomes of ‘Fuji’ Apples Through Short Term Cold and Room Temperature Storage
Thursday September 26, 2024 9:30am - 9:45am HST
Recent studies have shown that the native microbiome plays an important role in biocontrol efficacy, but in comparison less is known about how the microbiome responds to conventional and natural product fungicides. This study investigated the effects of conventional fungicide fludioxonil, natural product fungicide natamycin, and scald inhibitor diphenylamine (DPA) on the microbiomes of ‘Fuji’ apples (Malus x domestica) from 1-28 days of cold storage and 7 days of room temperature after the cold storage. We hypothesized that fludioxonil would have a smaller effect on the microbiome than natamycin due to being more limited in targeting specific pathogens, and that antioxidant activity from DPA would shift the microbiome. DPA showed a strong effect on the fungal microbiome that increased with storage time, while natamycin resulted in modest fungal shifts and fludioxonil resulted in no observed shifts. While chemical treatment was not a predictor of bacterial microbiome variation, bacterial communities shifted throughout storage with many of the trends reversing when samples were removed and left at room temperature. Time in cold storage decreased the relative abundance of Pseudomonas and DPA application reduced the relative abundance of Aureobasidium, both notable biocontrol genera. These results highlight how chemical applications like DPA may have unintended effects on beneficial microbes that protect crops from pathogen infection.
Speakers
CL

Connor Lane

Cornell University
Co-authors
CW

Chris Watkins

Cornell University
NA
JK

Jenny Kao Kniffin

Cornell University
NA
YA

Yosef Al Shoffe

Cornell Univeristy
Thursday September 26, 2024 9:30am - 9:45am HST
Nautilus 1

9:30am HST

TCHG 2 - Educational Initiatives in Cannabis: Curriculum Development for a Growing Workforce
Thursday September 26, 2024 9:30am - 9:45am HST
The cannabis and hemp industries have grown at a remarkable rate over the last decade, requiring the creation of comprehensive curricula to ensure proper workforce development. This discussion focuses on the educational initiatives employed at Cornell University to support industry growth and mitigate business failure in hemp-related fields. Our approach to curriculum design was tailored to meet the unique requirements for both undergraduate and graduate students, as well as industry stakeholders. This includes the creation of in-person and robust online hemp programs that are data-driven and up to date with the rapidly growing field of scientific knowledge. In doing so, we aim to ensure that students and the public are equipped with the most recent insights from scientifically-sound resources to support responsible practices within the industry, while also aligning with the institution’s curriculum standards. The School of Integrative Plant Science (SIPS) at Cornell University has been at the forefront of offering hemp-specific courses including Cannabis: Biology, Society and Industry, Hemp Breeding, Hemp Production, Hemp processing, and Chemistry and Pharmacology of Cannabis since 2019, with two of them also available through the online certificate program. Additionally, many professionals in the cannabis industry participated in the Cannabis Science and Hemp Sciences concentration for one year master’s degree program, Master of Professional Studies (MPS) at Cornell University, with approximately 30 students completing the degree in 2023. We will also highlight prior years' student expectations in order to suggest effective educational experiences and the challenges of this growing discipline in the absence of a comprehensive textbook. Through sharing insights, best practices, and case studies, this presentation aims to inspire dialogue and collaboration among educators, industry professionals, and legislators to advance the development of cannabis education within higher education institutions.
Speakers
YB

Yousoon Baek

Cornell University
Thursday September 26, 2024 9:30am - 9:45am HST
Kahili

9:30am HST

VCM 4 - Globe Artichokes - Variety Trials for Florida Production and Marketing Evaluations
Thursday September 26, 2024 9:30am - 9:45am HST
The globe artichoke (Cynara cardunculus) is a large thistle crop of the Asteraceae family, native to the Mediterranean. Globe artichokes are a large, leafy plant, with edible component as an immature flower bud. With production dominated by California, Florida can provide a new commodity for southeastern growers while reducing our carbon footprint. Globe artichokes have not been a traditional crop in the state of Florida, even as a garden variety. This study demonstrates the need to focus on varieties for the subtropics. We evaluated the best performing artichoke variety in addition to the retail favorite by curb appeal. Within a farmer's market survey, more than 80% of shoppers voted for 'Green Queen' amongst five other varieties (Imperial Star, Green Globe Improved, etc.). It also represented the highest yielding, at 12,707 lbs/acre, followed by 'Imperial Star' at 11,484 lbs/acre. An artichoke was valued at $4 each globe, while the flower was $5 per stem during the Mother's Day market. The demand continues from chefs and newly transplanted retail shoppers.
Speakers
EF

Evelyn Fletcher

University of Florida
I am the commercial row-crop Extension Agent for St. Johns County, FL.
Co-authors
KM

Kelly Morgan

UF/IFAS CALS
NA
SA

Shinsuke Agehara

University of Florida CALS
Thursday September 26, 2024 9:30am - 9:45am HST
Coral 2

9:44am HST

Organic Horticulture 2 (ORGH 2)
Thursday September 26, 2024 9:44am - 11:15am HST
Digging into Clover Living Mulch Effects on Soil - Connor Ruen
Effects of Mulch Type on Day-Neutral Strawberry Yield and Quality in an Organic Production System in the Upper Midwest - Mary Rogers
The Nebraska Urban Soil Health Initiative: Combined Effects of Cover Crops, No-till, Compost, and Biochar on Soil Health and Vegetable Crops - Collin Eaton
HydroMulcH2O: A Novel, Certifiably Organic, Biodegradable Mulch Technology for Northern Highbush Blueberries - Ben Weiss
Effect of Plastic Mulch, Living Mulches and Cover Crops on Soil Characteristics, Weed Pressure and Yield in Organic Globe Artichokes Production - Arianna Bozzolo
Eastern South Dakota Early Season Soil Tarping Impacts on Soil Microbiology - Hannah Voye
Moderator
BW

Ben Weiss

Washington State University
Ben is from Philadelphia and has been interested in food systems since an early age. He attended his first natural products expo before kindergarten because his parents worked in the natural foods industry. During late adolescence, he started a prolific tomato garden that blossomed... Read More →
Thursday September 26, 2024 9:44am - 11:15am HST
South Pacific 4

9:45am HST

O/LT 2 - Using Marketing Initiatives to Promote the UF/IFAS Extension Florida-Friendly Landscaping Program
Thursday September 26, 2024 9:45am - 10:00am HST
The UF/IFAS Florida-Friendly LandscapingTM (FFL) Program is Florida's premier Extension program for ecologically sustainable, science-based landscape practices that conserve water, protect water quality, and promote biodiversity. Since 1993, the FFL program has promoted water resource protection through both water conservation (water savings) and reducing non-point source pollutants (fertilizer nitrogen and phosphorus; pesticides) that may otherwise be carried into the state’s water bodies via runoff and/or leaching into groundwater. Despite longstanding promotion of FFL through Florida’s 67 county Extension offices, most Florida residents remain unaware of the program and its benefits. To promote public awareness of FFL, the program has undertaken a variety of marketing initiatives involving radio, television, social media, webinars, and online educational opportunities. On the radio, FFL produced a series of one-minute-long spots providing sustainable gardening tips. Called Florida-Friendly Landscaping in a Minute, the episodes aired twice each weekday on two NPR stations covering 19 northeast Florida counties. The daily listening audience was estimated at 4,600 for each airing, with 2.4 million total listeners each year. Webpage links to additional information back-up each episode. A wider audience was reached through the subsequent production of the Flip My Florida Yard television series. Produced in partnership with Crawford Entertainment with funding from the Florida Department of Environmental Protection, each 30-minute episode chronicles the complete makeover, or flip, of a homeowner’s typical Florida landscape into a more sustainable Florida-friendly landscape. All accomplished in eight hours, each episode features local designers and contractors and the local Extension agent, as well as a Maintenance Moment tip and a Yard Science segment featuring experts from UF/IFAS and other state entities. New shows air statewide on PBS and past episodes are streamed online. The program received a regional Emmy award in 2023. Flip My Florida Yard has been viewed more than 9.9 million times in the past year. FFL also recently hired a social media manager to increase FFL’s visibility on Facebook, Pinterest, Instagram, YouTube, and Linked-In. FFL’s social media reach is now growing exponentially. FFL also offers monthly webinars for both commercial and homeowner audiences. These webinars are archived to the FFL website and have accounted for more than 38,000 live and recorded views in the past year. Finally, the program has developed numerous online trainings and certification programs to help reach audiences at their convenience. As FFL begins its 32nd year, these marketing initiatives are helping it grow and reach new audiences.
Speakers
TW

Tom Wichman

FFL Assistant Dir., University of Florida
Co-authors
AG

Angela Gregory

UF/IFAS Extension Florida-Friendly Landscaping Program
NA
CL

Claire Lewis

UF/IFAS Extension Florida-Friendly Landscaping Program
NA
JM

Jen Marvin

UF/IFAS Extension Florida-Friendly Landscaping Program
NA
JB

John Bossart

UF/IFAS Extension Florida-Friendly Landscaping Program
NA
Thursday September 26, 2024 9:45am - 10:00am HST
South Pacific 1

9:45am HST

ORGH 2 - Digging into Clover Living Mulch Effects on Soil
Thursday September 26, 2024 9:45am - 10:00am HST
Living mulch research has focused on crop health without digging in to the effects on soil health. Soil management influences soil structure, water infiltration, and compaction. The recent drought has affected the Great Plains where precipitation is already limited. This makes it important for the water to infiltrate into the soil instead of running off, taking nutrients along with it. Soil compaction limits plant root’s ability to reach ground water and nutrients deeper in the soil profile which are needed during dry spells. In this study, living mulches of three established clover varieties, ‘Domino’ white clover (WC) (Trifolium repens), ‘Aberlasting’ white x kura clover (KC) (T. repens x ambiguum), and ‘Dynamite’ red clover (RC) (Trifolium pratense), bare ground control (BG), in combination with in-row management of tilled (T), no-tilled (NT), tilled fabric (TF), and no-tilled fabric (NTF) were evaluate for water infiltration, soil compaction, soil temperature and moisture. Water infiltration was measured using a 25.4 cm PVC ring which was pounded in the ground to prevent lateral flow. Water was added every minute to measure the infiltration rate. Soil compaction was measured using a SpotOn soil penetrometer measuring the PSI needed to pass through the soil. Soil moisture and temperature were measured every hour using HOBO MX soil moisture and temperature logger. Water infiltration in NT soil management had a was 67% greater when compared to T soil management. Soil compaction readings from 0-15 cm had a range from 324 PSI in NT to 351 PSI in NTF. After one year of changing the soil management, there was a significant increase in on water infiltration rate in the NT which means the soil can handle much larger volumes of water compared to T. Soil compaction has changed very little between soil managements which can be expected since it takes many years to break compaction layers and improve the soil structure. Soil management can improve water infiltration rates which increases the water added to the soil and decreases the risk of erosion. More time is required to determine how soil management will affect compaction in this study.
Speakers
CR

Connor Ruen

South Dakota State University
NA
Co-authors
KL

Kristine Lang

South Dakota State University
TN

Thandiwe Nleya

South Dakota State University
NA
Thursday September 26, 2024 9:45am - 10:00am HST
South Pacific 4

9:45am HST

PH 3 - Pyrus communis: A Model for Studying Climacteric Ripening and Senescence
Thursday September 26, 2024 9:45am - 10:00am HST
Fruits constitute a critical part of a healthy diet. However, they often perish prior to consumption due to unpredictable ripening. Especially in climacteric fruit, blockage in the perception or synthesis of ethylene has been used to prolong shelf life. European pear (Pyrus communis) are classified as climacteric fruit. However, System 2 ethylene production requires a genetically pre-determined period of cold conditioning, which triggers ripening—in addition, applying 1-MCP, an ethylene perception inhibitor, indefinitely blocks ripening. Using a physiological and developmental transcriptomics approach, we have shown that in 1-MCP fruit stored in a controlled atmosphere, activating alternative respiration via glyoxylic acid stimulation of AOX expression can reverse the effect of 1-MCP. Interestingly, 1-MCP fruit without CA storage responds differently to glyoxylic acid. It shows classic signs of senescence. The underlying processes of ripening and senescence can be discerned by utilizing the fruit that has been treated differently post-1-MCP application. This knowledge is expected to aid in identifying strategies to prolong fruit shelf life.
Speakers
avatar for Amit Dhingra

Amit Dhingra

Head of the Department of Horticultural Sciences, Texas A&M University
Dr. Amit Dhingra is the Head of the Department of Horticultural Sciences, Professor of Genomics and Biotechnology, and Senior Scientist at the Norman Borlaug Institute for International Agriculture at Texas A&M University. After his post-doctoral training at Rutgers University, the... Read More →
Co-authors
EC

Evan C. Stowe

Washington State University
NA
SL

Seanna L. Hewitt

Washington State University
NA
Thursday September 26, 2024 9:45am - 10:00am HST
Nautilus 1

9:59am HST

Technology Applications in Horticulture 2 (TECH 2)
Thursday September 26, 2024 9:59am - 11:15am HST
Development of Crop Water Stress Index for Hazelnuts in the Willamette Valley Using Distributed Low-Cost Infrared Thermometers - Dalyn McCauley
Performance Evaluation of a Robust Chip-based RF sensor for Soil Moisture Determination - Jannatul Ferdaous Progga
Development and Demonstration of a Sensor-Based Method for Monitoring Container Substrate Fertility - Michelle Ezequelle
Enhancement of air quality in agricultural facility using particulate matter reduction systems - hyojae Seo
Experience with New Generation Horticultural Education, Research and Production Through Indoor Ag. - Bipul Biswas

Moderator
BB

BIPUL BISWAS

FORT VALLEY STATE UNIVERSITY
Thursday September 26, 2024 9:59am - 11:15am HST
Kahili

9:59am HST

Weed Control and Pest Management 3 (WCPM 3)
Thursday September 26, 2024 9:59am - 11:30am HST
A Water Soluble β-triketone Enriched Extract of Manuka Oil has Increased Efficacy Compared to Vinegar and D-Limonene in a Field and Greenhouse Evaluation - Casey Barickman
Weed Control in Bell Pepper after Herbicide Application in a Reduced Sunnhemp Cover Crop Population. - Peter Dittmar
Assessing the Effects of Container Sizes and Weed Densities on Weed-ornament Competition in Nursery Container Production - Debalina Saha
Herbicide-Resistant Italian Ryegrass in Oregon Hazelnut Orchards: Evaluating Nonchemical and Chemical Methods - Marcelo Moretti
Limiting Liverwort Growth by Allelopathic Effects of Organic Mulches in Ornamental Production - Manjot Sidhu
Effect of Application History on Preemergence Herbicide Persistence - Travis Gannon

Moderator
PD

Peter Dittmar

University of Florida
Thursday September 26, 2024 9:59am - 11:30am HST
Lehua Suite

9:59am HST

Pomology 3 (POM 3)
Thursday September 26, 2024 9:59am - 11:45am HST
Seven-year Yield and Fruit Quality Comparison of Four Apple Cultivars Between Tall Spindle and Bi-axis Systems in Western New York - Brian Lawrence
After Avery: Apple Photosynthesis and Evidence of a Changing Environment. A Historical and Technical Evaluation - Curt Rom
The Biological Mechanism Behind Early and Late Apple Sports - Alexander Engelsma
Characterizing Unique Apple Selections for U-Pick Growers in the Midwest Using Descriptive Analysis, Consumer Liking Tests, and Phytochemical Analysis - Lydia Balogh
Selection and Patenting of New, Grower Friendly Apple Trees by the Maryland Tree Architecture Project - Chris Walsh
Effects and Interactions of Water Stress and Rootstock on Physiological Responses and Ambrosia Beetle Colonization of Apple Trees - Melissa Munoz
The Role of Photosynthesis in the Regulation of Early Fruit Growth of Apple - Bayleigh Roussel

Moderator
MM

Melissa Munoz

NC State University
Thursday September 26, 2024 9:59am - 11:45am HST
South Pacific 2

9:59am HST

Growth Chambers and Controlled Environments 5 (CE 5)
Thursday September 26, 2024 9:59am - 12:00pm HST
Quality Analysis of Bitter Acids in Hops (Humulus lupulus L.) from a Controlled Environment Versus Field Production System - katie stenmark
The Affect of High pH on Hydroponic Lettuce in a Controlled Environment - Alexander Speck
Drought Stress Responses of North American Native Bog Birch and Sweetgale in a Sensor-automated System - Jessica Hutchinson
Effects of Plant Growth Promoting Rhizobacteria on Yield of Amaranth viridis Linn. Grown in a Growth Chamber and Greenhouse - Zachary Williams
Shade-Avoidance Responses of Kale and Lettuce Elicited by Far-Red Light Can Persist Under High-Light Intensity - Jiyong Shin
Does Intermittent and Continuous Nutrient Flow Affect the Growth and Phytochemicals of Culinary Herbs in NFT Hydroponics - Abishkar Regmi
Adjusting Supplemental LED Light Intensities Based on Real-time Chlorophyll Fluorescence Measurements in a Greenhouse - Suyun Nam
Interactions of Far-Red Photons with Orange Photons or Red Photons: Photosynthetic Response, Morphology and Fruit Yield - Seonghwan Kang
Speakers
KS

katie stenmark

OKLAHOMA STATE UNIVERSITY
Crop Science PhD Student Department of Horticulture and Landscape Architecture Oklahoma State University
Thursday September 26, 2024 9:59am - 12:00pm HST
South Pacific 3

10:00am HST

CE 5 - Quality Analysis of Bitter Acids in Hops (Humulus lupulus L.) from a Controlled Environment Versus Field Production Syst
Thursday September 26, 2024 10:00am - 10:15am HST
Hop plants are produced for harvest of mature hop cones that are utilized in the medicinal, agricultural, cosmetic and craft beer industries. Hop plants are vigorously climbing perennials that require shorter than 15-hour days for flowering induction, and a trellis structure (3-6m annual height) for seasonal support. In the United States, the majority of hops are grown in field production systems in the Pacific Northwest where summer day lengths are long. The demand for hops has increased due to a boom in the craft beer industry which has led growers in southern states to seek alternative methods for producing hops outside of their traditional commercial growing region. Hop performance in greenhouse systems has not been evaluated in Oklahoma before, but controlled environments offer an alternative for hop producers in the south to limit pests, reduce contact with Downy Mildew (Pseudoperonospora humuli), and harvest multiple crops per year. Four cultivars of hops (‘Cascade’, ‘Comet’, ‘Newport’, ‘Tahoma’) were grown on a 3m trellis using a Dutch bucket hydroponic system with one rhizome per bucket spaced 0.5m apart without supplemental lighting in the USDA research greenhouses at Oklahoma State University. Four identical cultivars of hops were grown in a field system using a V-style trellis (5m height) at the Cimarron Valley Research Station in Perkins, OK. Mature hop cones were hand harvested at 80% moisture and dried at ambient temperature to 8-10% moisture. Hops were stored for up to six months frozen under nitrogen in vacuum sealed bags until analysis was performed. Hop bitter acids (α-acids and β-acids) were extracted using a 0.1% formic acid solvent, and hop quality was determined by HPLC. Bitter acids of greenhouse hops were determined to be highest in cultivars ‘Comet’ (α- 2.12%, β- 0.73%), ‘Cascade’ (α- 2.00%, β- 1.04%), and ‘Tahoma’ (α- 1.92%, β- 1.23%), where ‘Newport’ had a notably lower α and β-acid content (α- 0.71%, β- 0.81%). Bitter acid quality in field hops were comparable to hops produced in the greenhouse (‘Cascade’ α- 2.99%, β- 1.77%; ‘Newport’ α- 2.95%, β- 1.56%; ‘Tahoma’ α- 1.42%, β- 1.56%; ‘Comet’ α- 1.95%, β- 0.71%). With the information from this research, local greenhouse growers will be able to determine if hops are a viable option for their region.
Speakers
KS

katie stenmark

OKLAHOMA STATE UNIVERSITY
Crop Science PhD Student Department of Horticulture and Landscape Architecture Oklahoma State University
Co-authors
BD

Bruce Dunn

OKLAHOMA STATE UNIVERSITY
CF

Charles Fontanier

OKLAHOMA STATE UNIVERSITY
NA
VH

Victoria Hughes

OKLAHOMA STATE UNIVERSITY
NA
Thursday September 26, 2024 10:00am - 10:15am HST
South Pacific 3

10:00am HST

ORGH 2 - Effects of Mulch Type on Day-Neutral Strawberry Yield and Quality in an Organic Production System in the Upper Midwest
Thursday September 26, 2024 10:00am - 10:15am HST
Organic, locally produced strawberries are in high demand in the Upper Midwest. Day-neutral cultivars fit well within an annual production system, allow growers an extended harvest period, and previous research shows they can be productive in our region. However, key production challenges limit adoption of organic production of day-neutral strawberries including weed, insect, and disease pressure. To address these challenges, we established controlled experiments investigating the effects of four different mulch types: white-on-black poly (standard), black poly, reflective metallic poly, and biodegradable paper mulch on yield and quality of ‘Cabrillo’ strawberries across two years (2022 and 2023) and two locations (Madison, WI and St. Paul, MN). Our results show that strawberry yield ranged from 5,000 - 18,000 lbs per acre across treatments and years. The highest yields were achieved in 2023 in Wisconsin in the reflective metallic poly treatment, which was significantly different from the white-on-black treatment in the same year. Proportion marketable yield was equal between treatments in both years in Wisconsin and in 2022 in Minnesota, however we observed a significant decline in marketable fruit quality in Minnesota in 2023 under the paper treatment compared to black plastic.The paper mulch broke down before the end of the production season in Minnesota in both years which led to increased weed pressure and reduce fruit quality; however paper mulch retained at least 90% coverage and integrity in Wisconsin across both years. Tarnished plant bugs (TPB) are a key pest in this system and will significantly reduce fruit yield and quality if not managed. In both Minnesota and Wisconsin, TPB damage was higher in our standard white-on-black poly compared to the reflective metallic poly mulch in both years. In addition, thrips counts were significantly higher on white-on-black poly compared to reflective metallic poly in Minnesota in both years. Anthracnose fruit rot was the most common disease observed and was most common in the white-on-black poly treatment. Anthracnose was also a significant problem on row edges where weeds were actively growing and retaining moisture near the fruits. Overall, reflective metallic poly mulch significantly reduces strawberry insect pest pressure while maintaining yield and fruit quality and outperforms the current grower standard white-on-black plastic mulch. Price premiums for organic strawberries marketed direct by growers combined with the longer day-neutral production season, make day-neutral strawberries financially lucrative despite production issues and high labor requirements.
Speakers Co-authors
AA

Amaya Atucha

University of Wisconsin Madison
CG

Christelle Guedot

University of Wisconsin - Madison
EB

Eric Burkness

University of Minnesota
NA
GD

Gigi DiGiacomo

University of Minnesota
NA
JM

Jarret Miles-Kroening

University of Wisconsin
NA
Thursday September 26, 2024 10:00am - 10:15am HST
South Pacific 4

10:00am HST

PH 3 - Characterization of Postharvest Rots and the Susceptibility to Decay of 38 European Pear Genotypes during Cold Storage.
Thursday September 26, 2024 10:00am - 10:15am HST
Phytopathogenic fungi can cause rots during cold storage leading to the loss of pear fruit and significant economic costs. Currently, all commercially available pear varieties are susceptible to postharvest rots. Genetic resistance to fruit rot pathogens including Penicillium expansum and Colletotrichum spp. has been identified in wild apple germplasm. The objective of this study was to evaluate diverse genotypes of European pears (Pyrus communis L.) for disease incidence during cold storage and evaluate susceptibility to prevalent phytopathogenic fungi by directly challenging fruit using a wound inoculation method. Fruit from 38 pear genotypes were harvested at maturity, then evaluated weekly for the presence of postharvest rots during cold storage. If rot was observed, the diseased fruits were removed from cold storage and fungal isolates were collected from fruit with disease symptoms. The identity of fungal isolates was determined based on morphology and genetic sequencing of marker genes including ITS and TEF1. After 12 weeks in cold storage, the incidence of rot ranged from 8.3% to 100%. Colletotrichum was the most prevalent genus isolated from the rotting pears. Twenty pear genotypes were directly challenged with P. expansum or C. fioriniae using a wound inoculation method on fruit that was harvested at commercial maturity. Five genotypes had significantly reduced disease development when challenged with P. expansum compared to susceptible varieties Gem and Bartlett. Four of these five genotypes also had significantly reduced disease development when challenged with C. fioriniae. One additional genotype was found to have significantly reduced disease development when challenged with C. fioriniae but was highly susceptible to P. expansum. These results will be a valuable resource for pear breeders and aid efforts to develop European pear varieties that have genetic resistance to fruit rot pathogens.
Speakers Co-authors
BE

Breyn Evans

USDA ARS
NA
CB

Caitlin Barnes

USDA ARS Appalachian Fruit Research Station
NA
CG

Christopher Gottschalk

USDA ARS
During his Ph.D. studies, Dr. Gottschalk studied the molecular mechanisms that control flowering in apple as they relate to seasonal bloom times and biennial/alternate bearing in diverse apple germplasm, from wild species to cultivated varieties. Moreover, he investigated plant growth... Read More →
JB

John Bennett

USDA ARS
NA
Thursday September 26, 2024 10:00am - 10:15am HST
Nautilus 1

10:00am HST

POM 3 - Seven-year Yield and Fruit Quality Comparison of Four Apple Cultivars Between Tall Spindle and Bi-axis Systems in Western New York
Thursday September 26, 2024 10:00am - 10:15am HST
Increasing orchard planting density has helped improve grower profits and yields but establishment costs can be high. It is believed that by using bi-axis trees the number of trees required during planting can be reduced while possibly improving yields and fruit quality. To test this possibility, an orchard of four cultivars (‘Brookfield Gala’, ‘Aztec Fuji’, ‘Honeycrisp’, and ‘Ruby Mac’) was established and trained to either Tall Spindle (TS) or Bi-axis (BA) at 1m x 4m spacing. After the third year of growth, all TS trees and half of BA trees were summer hedged, resulting in three systems to compare: 1) TS hedged; 2) BA hedged; and 3) BA non-hedged. Measurements of trunk cross sectional area (TSCA), phenology, yield, and fruit quality were recorded for seven years to calculate cumulative values. At the end of the study, TSCA was larger on TS trees compared to hedged or non-hedged BA trees across cultivars. Biennial bearing was lower with ‘Brookfield Gala’ and ‘Aztec Fuji’ compared to ‘Honeycrisp’ and ‘Ruby Mac’ and trended lower on hedged or non-hedged BA trees than TS trees. The hedged or non-hedged BA trees had higher cumulative yields compared to TS trees across cultivars. Fruit size was reduced on hedged or non-hedged BA trees compared to TS trees, but all three systems had similar fruit color, firmness, and soluble solids on average. After seven years, there was no obvious benefit of using hedged or non-hedged BA systems to improve fruit quality, but higher yield from BA trees over TS trees when planted at the same density, regardless of hedging during the summer, was achieved. We calculated that BA trees could be planted at 15% lower planting density than TS trees to achieve the same yield.
Speakers
BL

Brian Lawrence

Cornell University
Co-authors
TR

Terence Robinson

Cornell University
NA
Thursday September 26, 2024 10:00am - 10:15am HST
South Pacific 2

10:00am HST

TECH 2 - Development of Crop Water Stress Index for Hazelnuts in the Willamette Valley Using Distributed Low-Cost Infrared Thermometers
Thursday September 26, 2024 10:00am - 10:15am HST
Incorporating data-driven technologies into agriculture offers an effective strategy for optimizing crop production, particularly in regions reliant on irrigation. This becomes increasingly crucial in the face of escalating heatwaves and droughts associated with climate change. Recent advancements in sensor technologies have spawned various methods for assessing irrigation needs. Notably, infrared thermometry stands out as a non-destructive remote sensing method capable of monitoring transpiration, holding significant potential for integration into drone- or satellite-based remote sensing models. This study focuses on the application of infrared thermometry to develop a Crop Water Stress Index (CWSI) model for European hazelnuts (Corylus avellana), a significant crop in Oregon, the leading hazelnut-producing state in the United States. Using low-cost open-source infrared thermometers and data loggers, this research aims to provide hazelnut farmers with a practical tool for monitoring crop water status, improving irrigation efficiency, and ultimately enhancing hazelnut yields. The study, spanning from June to September 2021 in a ‘Jefferson’ hazelnut (Corylus avellana) orchard, applied three distinct irrigation treatments. The calibration of the low-cost IRT sensors achieved a high accuracy (R² = 0.99), validating their utility in detecting variations in canopy temperature consistent with irrigation treatments. The developed CWSI is well-correlated with traditional plant water status indicators including stem water potential, leaf conductance, and transpiration. These results demonstrate the potential of this model to accurately reflect physiological symptoms of water stress in hazelnuts. This research not only introduces a novel CWSI model tailored to hazelnuts but also underscores the utility of low-cost technology in enhancing agricultural monitoring and decision-making.
Speakers
DM

Dalyn McCauley

Oregon State University
Co-authors
LN

Lloyd Nackley

Oregon State University
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
NW

Nik Wiman

Oregon State University
NA
Thursday September 26, 2024 10:00am - 10:15am HST
Kahili

10:00am HST

WCPM 3 - A Water Soluble β-triketone Enriched Extract of Manuka Oil has Increased Efficacy Compared to Vinegar and D-Limonene in a Field and Greenhouse Evaluation
Thursday September 26, 2024 10:00am - 10:15am HST
Weed management strategies for specialty and organic crop production are challenging due to limited chemical weed control products with good efficacy that are cost effective. The need for new bioherbicide modes of action has become increasingly urgent in modern agriculture as most bioherbicides have nonspecific modes of action with no systemic activity. Introducing new modes of action is essential to diversify weed control strategies, minimize the risk of resistance development, and ensure sustainable weed management practices. By fostering innovation in bioherbicide development and promoting the use of novel modes of action, we can safeguard our agricultural systems, reduce the environmental impact of weed management, and maintain the ability to feed a growing global population while preserving the long-term health of our ecosystems. Manuka oil is derived from the leaves and branches of the Manuka tree (Leptospermum scoparium) and contains β-triketones. The β-triketone rich fraction contains leptospermone and inhibits a key enzyme, p-hydroxyphenylpyruvate dioxygenase (HPPD). This process directly inhibits carotenoid biosynthesis, upstream in the biochemical pathway, which causes damage to the photosynthetic apparatus and leads to bleaching of the leaf tissue which eventually kills the plant. The β-triketone extract at 2% and 4% had up to 97% control against different weed species in field and greenhouse evaluations. The β-triketone extract was significantly more efficacious verse other bioherbicides such as the 20% vinegar and 12.5% D-limonene. Additionally, the β-triketone extract was just as effective as the 2% glyphosate treatment in the greenhouse evaluation against Amaranthus palmeri and Digitaria sanguinalis. The β-triketone extract also reduced Cyperus esculentus growth by 70% at 9 days after treatment. Thus, there is significant evidence that commercializing a water soluble β-triketones enriched extract of Manuka oil can be an effective weed control strategy in crop production systems, especially in specialty and organic cropping systems where the need of bioherbicides is critically imperative.
Speakers Co-authors
AR

Amber Reichley

USDA-ARS
NA
CL

Charles L. Cantrell

USDA-ARS-NPURU
NA
Thursday September 26, 2024 10:00am - 10:15am HST
Lehua Suite

10:00am HST

Specialty Crops Collaboration Session
Thursday September 26, 2024 10:00am - 11:00am HST
A forum for discussion of potential collaborations with regards to specialty crops – i.e. hemp, herbs, medicinal plants, and tropicals, breeding, production, etc.
Thursday September 26, 2024 10:00am - 11:00am HST
Coral 4

10:00am HST

Workshop: Personifying Tomorrow's Clients: Transforming Data into Tools for Reaching Consumer Horticulture Audiences
Thursday September 26, 2024 10:00am - 12:00pm HST
Whether marketing to a horticulture consumer or educating them, understanding motivations is crucial. In 2023, a nationwide survey of gardening consumers conducted by a regional team of horticulture researchers provided key insights into how backgrounds and experiences impacted motivations of horticulture consumers. Cluster analysis performed on the data provides the ability to group consumers in terms of their interest and spending to enable more tailored education or marketing efforts. This workshop will investigate the key characteristics of those ten groups according to demographics, experience, motivation, and spending and integrate the experience and insight of attendees to best utilize the survey information. The goal of this highly interactive workshop will be to develop representative avatars and actionable outreach and marketing ideas that can be integrated into Extension programming as well as used to equip garden centers and horticultural businesses to be intentional and effective in reaching, educating, and retaining these new consumers. Horticulture professionals with research, Extension, teaching, and/or business focuses are all invited to attend and aid in honing audience descriptions based on current data. This session will set the stage for developing more tools to support Consumer Horticulture outreach and marketing to current and future audiences.

This workshop is grounded in current research findings and will focus on turning findings into tools that can be used by a wide range of ASHS professionals to reach current and future audiences.

Engage a diverse set of Horticulture professionals and define up to 10 core target audiences in today's horticultural market whether that is a retail business, classroom, or other outreach program.

This session will have minimal large-group presentation time. Six team leaders will break the audience into small groups based on interests and lead them through a series of prompts to assign descriptors to different audiences as defined by recent survey data. Participants will aid in coding different types of audience members, report out to the larger group, and group work will be cross-checked to determine key target audiences and best methods of communication with each.

Coordinator(s)
  • Kristine Lang, South Dakota State University, Agronomy, Horticulture, and Plant Science, Brookings, South Dakota, United States
Moderator(s)
  • Gerald Burgner, Texas A&M University, United States
  • Natalie Bumgarner, University of Tennessee, Plant Sciences, Knoxville, TN, United States
  • Sheri Dorn, University of Georgia, United States
  • Heather Kirk Ballard, Louisiana State University, United States
  • Julie Campbell, University of Georgia, Horticulture, Athens, Georgia, United States

Moderator
NB

Natalie Bumgarner

Assistant Professor, University of Tennessee Knoxville
KL

Kristine Lang

South Dakota State University
Thursday September 26, 2024 10:00am - 12:00pm HST
Coral 2

10:00am HST

ASHS Board of Directors Meeting
Thursday September 26, 2024 10:00am - 2:30pm HST
Thursday September 26, 2024 10:00am - 2:30pm HST
Sea Pearl 3

10:14am HST

Plant Nutrient Management 2 (PNM 2)
Thursday September 26, 2024 10:14am - 11:15am HST
Soil Amendments Alter Soil Chemical Properties and Toxic Elements Accumulation in Sweetpotato cvs. Bayou Belle and Beauregard - Mae Ann Bravo
Methods of Fertilization in Commercial Production of Saw Palmetto (Serenoa repens Small (Bartr.) form green and glauca) -Vania Pereira
Iron Biofortification in Radish and Pea Microgreens Using Alternative Iron Sources and Ascorbic Acid -Rishi Ravichandran
Combined Agronomic Biofortification of Iron and Zinc in Radish and Sunflower Microgreens - Rishi Ravichandran
Moderator
MA

Mae Ann Bravo

Louisiana State University
Thursday September 26, 2024 10:14am - 11:15am HST
Coral 1

10:14am HST

Fruit Breeding 1 (FRBR 1)
Thursday September 26, 2024 10:14am - 12:00pm HST
Validation of Diagnostic Markers for Stenospermocarpic Seedlessness and Flower Sex in Diverse Muscadinia and Vitis Grape - Isabella Vaughn
High-Density Linkage Mapping and Identification of Quantitative Trait Loci Associated with Leaf-Scab Resistance in Pecan - Gaurab Bhattarai
Genome Wide Association Studies Unmasks Loci Associated With Fruit Size and Sugar Content in Mango - Vincent Njung'e Michael
A Genome-Wide Association Study To Identify Loci Underlying Fruit Color In Red Raspberry - Claudia Baldassi
Relatedness of Luther Burbank’s Plum (Prunus sp.) Introductions based on Genotyping by Sequencing (GBS) - Rachel Spaeth
A Deep Learning‐based Smartphone App for Blueberry Yield Prediction - Sushan Ru
Utilizing Optical Sorting Technology for High-Throughput Phenotyping in Sweet Cherry Breeding - Per McCord
Moderator
PM

Per McCord

WASHINGTON STATE UNIVERSITY
Thursday September 26, 2024 10:14am - 12:00pm HST
South Pacific 1

10:15am HST

CE 5 - The Affect of High pH on Hydroponic Lettuce in a Controlled Environment
Thursday September 26, 2024 10:15am - 10:30am HST
In North Dakota, indoor-grown lettuce faces water pH levels higher than the ideal 5.5 to 6.5 range, with Fargo's water averaging a pH of 9.2 from 2018 to 2022. Addressing the gap in research on high pH's impact on lettuce, this study, running from 2023 to 2024, explored the effects of pH levels on the yield of lettuce grown in deep water culture (DWC) hydroponic systems. We tested three lettuce varieties (Casey, Gladius, and Tendita) under four pH conditions (6.3, 7.0, 8.3, and an unbuffered level), with each setup replicated four times. Th initial growth was in rock wool cubes under a clear dome for a month before transferring to DWC for another month. The results indicated significant differences in yield and size across pH levels and varieties. Gladius yielded the highest at pH 6.3 (86.0 g/plant), while Casey showed the lowest yield at pH 7.0 (9.6 g/plant). Gladius also achieved the largest diameter (25.1 cm) at pH 6.3, contrasting with Casey's smallest at 7.0 pH (10.2 cm). Notably, high pH (8.3) still produced reasonable yields and sizes, especially with the Gladius variety, highlighting the potential for selecting suitable varieties to mitigate adverse pH effects. This study underscores the importance of variety selection in hydroponic systems with non-ideal water pH, providing crucial insights for optimizing indoor lettuce production.
Speakers
AS

Alexander Speck

North Dakota State University
Co-authors
XF

Xiaoyu Feng

North Dakota State University
XJ

Xinhua Jia

North Dakota State University
Thursday September 26, 2024 10:15am - 10:30am HST
South Pacific 3

10:15am HST

FRBR 1 - Validation of Diagnostic Markers for Stenospermocarpic Seedlessness and Flower Sex in Diverse Muscadinia and Vitis Grape
Thursday September 26, 2024 10:15am - 10:30am HST
Muscadine grapes (Muscadinia rotundifolia) are perennial vines grown commercially in the Southeast United States for the fresh market and as wine and juice grapes. Two highly sought-after traits in fresh market muscadine cultivars are stenospermocarpic seedlessness and perfect-flowered vines. However, the genetic disparity between Vitis and Muscadinia subgenera, coupled with differing chromosome numbers (Vitis=38 chromosomes, Muscadinia=40 chromosomes), presents challenges in introgression of stenospermocarpy from V. vinifera to M. rotundifolia. Although conventional breeding has introduced stenospermocarpy into M. rotundifolia, no molecular markers for this trait have been validated in muscadines. Recently, two Kompetitive Allele Specific PCR (KASP) markers targeting candidate genes for male sterility (VviINP1) and stenospermocarpy (VviAGL11) in V. vinifera have shown promise. Sequence comparisons with published V. rotundifolia genomes suggest that these markers might be effective across diverse Vitis, Muscadinia, and wide hybrid germplasm. In this study, we validated the predictive ability of KASP markers for flower sex and stenospermocarpy across thirteen Vitis x Muscadinia hybrid seedling populations and 191 diverse genotypes. In 2023, 891 seedlings were evaluated for seedlessness, with an additional 214 seedlings assessed for flower sex. Furthermore, 191 diverse accessions underwent evaluation for both flower sex and seedlessness. Of the 891 seedlings, 66 were seedless, 490 were seeded, and 335 could not be phenotyped due to fruit absence. Among the 214 seedlings assessed for flower sex, 88 were perfect, 106 were female, and 20 could not be phenotyped due to flower absence. The stenospermocarpy marker accurately predicted 771 of 783 seedlings and diverse material, while the flower sex marker matched 366 of 383 seedlings and diverse accessions. Discrepancies between marker predictions and observed phenotypes may be due to human error or pollen sterility. Notably, most fruitless seedlings were predicted to be stenospermocarpic, indicating potential issues with partial sterility or cold hardiness in seedless hybrids. We intend to reevaluate the populations for flower sex and seedlessness in summer 2024 to address discrepancies. Overall, the KASP markers developed in V. vinifera exhibited excellent predictive ability across diverse germplasm, offering valuable insights for muscadine breeding programs.
Speakers
IV

Isabella Vaughn

University of Arkansas
Co-authors
CJ

Carmen Johns

University of Arkansas
CZ

Cheng Zou

BRC Bioinformatics Facility, Institute of Biotechnology, Cornell University
NA
LN

Lacy Nelson

University of Arkansas
NA
LC

Lance Cadle Davidson

United States Department of Agriculture-Agricultural Research Service, Grape Genetics Research Unit
NA
MW

Margaret Worthington

University of Arkansas
NA
QS

Qi Sun

BRC Bioinformatics Facility, Institute of Biotechnology, Cornell University
NA
Thursday September 26, 2024 10:15am - 10:30am HST
South Pacific 1

10:15am HST

ORGH 2 - The Nebraska Urban Soil Health Initiative: Combined Effects of Cover Crops, No-till, Compost, and Biochar on Soil Health and Vegetable Crops
Thursday September 26, 2024 10:15am - 10:30am HST
Adoption of soil health management practices like cover crops, no-till, and organic soil amendment is increasing in rural agroecosystems, but less in known about whether urban farmers and gardeners are using these practices and how implementing these practices might influence their soil. To address this knowledge gap, we started the Nebraska Urban Soil Health Initiative to 1) benchmark soil health and current management practices in urban gardens throughout Nebraska, and 2) evaluate the effects of adding new soil health management practices on urban soil health and crop performance. Using a citizen-science approach, we recruited and have retained over 300 participants who collect annual soil samples, complete surveys about their practices and knowledge, and implemented an assigned soil health management practice. Soil health management practice treatment groups ranged from low (e.g., individual practices) to high management intensities (e.g., combinations of practices) and include: 1) a cover crop mixture; 2) no-till with geotextile fabric; 3) compost soil amendment; 4) biochar soil amendment; 5) cover crop mixture no-till; 6) cover crop mixture no-till compost, or 7) cover crop mixture no-till compost biochar. Prior to implementing, most participants (>70%) had positive perceptions about cover crops, no-till, and compost soil amendment, whereas >60% had no opinion or prior knowledge about biochar soil amendment. Over 50% of participants characterized their garden weed pressure as somewhat to very high and over 60% reported very low to low pesticide use, which suggests room for improvement using cover crops and a no-till weed barrier. Baseline soil P across gardens was 186 mg/kg (above a sufficiency level of 25 mg/kg in 98% of gardens) and average soil organic matter was 6.9%, which suggests a legacy of compost amendment to meet crop nitrogen needs. Biochar soil amendment (8 tons/acre) alone reduced zucchini yield by 37%, but yield loss was avoided by pairing biochar with compost and the weed barrier. Initial changes in soil health among participant gardens following implementation of new practices in year one will be analyzed along with year two sweet corn crop response.
Speakers
CE

Collin Eaton

University of Nebraska - Lincoln
NA
Co-authors
MK

Michael Kaiser

University of Nebraska - Lincoln
NA
RS

Ronald Stephenson

University of Nebraska-Lincoln
NA
SW

Samuel Wortman

University of Nebraska - Lincoln
XC

Xinzheng Chen

University of Nebraska - Lincoln
NA
Thursday September 26, 2024 10:15am - 10:30am HST
South Pacific 4

10:15am HST

PNM 2 - Methods of Fertilization in Commercial Production of Saw Palmetto (Serenoa repens Small (Bartr.) form green and glauca)
Thursday September 26, 2024 10:15am - 10:30am HST
Saw palmetto is an endemic palm of the Southeastern United States that has been widely used as an ornamental food source for birds and mammals, and the fruit is used as a medicinal supplement for prostate cancer. The production of this palm still relies on wild harvesting. We analyzed the effects of different fertilization methods on the plant growth and fruit production of two saw palmetto forms (green and silver) from 2022 to 2023. Fertilization methods consisted of 1. Control- no fertilizer application; 2. Injection by Arbor-Jet: Palm-Jet Mg 1-2-2 (N-P2O5-K2O) 2.5 ml per plant once a year (ArborJet, Woburn, MA); 3. Granular (Harrell’s, Lakeland, FL): 8-2-12 4 Mg (N-P2O5-K2O 4 Mg) with micronutrients 146 g/m2 of plant canopy; 4: Granular and drench fertilizer: 8-2-12 4 Mg with micronutrients 146 g/m2 with drench application – 20-10-20 Epsom salts Non-staining Micros (Harrell’s MAX, liquid foliar nutritional, Lakeland, FL). Treatments 3 and 4 were applied every three months for a year. Green saw palmetto only differed and performed better than silver form in the number of leaves and offshoot per plant. The granular and granular with drench fertilization provided the best plant growth rates, regarding plant height, width, visual quality, and green canopy cover, then control and injection treatments. Even though the drench had a higher supply of nutrients for the plants, the differences were not statistically significant from granular fertilization.
Speakers
VP

Vania Pereira

University of Florida
Co-authors
KW

Karen Williams

University of Florida
NA
MM

mica mcmillan

University of Florida
PR

Patricia Ramos Barros

University of Maryland
NA
TS

Thiago Souza Campos

University of Florida
NA
WV

Wagner Vendrame

University of Florida
NA
Thursday September 26, 2024 10:15am - 10:30am HST
Coral 1

10:15am HST

POM 3 - After Avery: Apple Photosynthesis and Evidence of a Changing Environment. A Historical and Technical Evaluation
Thursday September 26, 2024 10:15am - 10:30am HST
In 1977 Avery published a review of apple leaf photosynthesis (Pn) rates to estimate maximum rates with current technologies and conditions. This presents a recent review of more than 90 published reports of apple photosynthesis from 1978-2022 evaluated the techniques and equipment used, the experimental parameters of CO2, temperature, light, and vapor pressure deficit. The goal of the review was to determine if techniques used reflected changes in global atmospheric [CO2], and if there was evidence of response of apple leaves to changing [CO2] with time. Avery in 1977 estimated mean apple Pn rate to be ca. 14 µgCO2m-2s-1 and a maximum rate of ca. 22 µgCO2m-2s-1. The current review suggests an estimated mean apple Pn rate to be ca. 15.6 µgCO2m-2s-1 , similar to Avery, but a maximum rate of ca. 31-35 µgCO2m-2s-1, higher than Avery. Since 1977, there has been an approximately 26% increase in global CO2. There was no correlation between experimental [CO2] or atmospheric [CO2] and reported Pn, and although reported Pn rates tended to increase with time, there was no significant correlation to time. Experimental[CO2] was reported in 58% of the reports but omitted in others. Experimental parameters of measurement temperature or vapor pressure deficit were commonly not reported.
Speakers
Thursday September 26, 2024 10:15am - 10:30am HST
South Pacific 2

10:15am HST

TECH 2 - Performance Evaluation of a Robust Chip-based RF sensor for Soil Moisture Determination
Thursday September 26, 2024 10:15am - 10:30am HST
Controlling water cycles, anticipating disasters, and enhancing agriculture depends on accurate soil moisture understanding. To address climate-related challenges, precise and real-time measurements from soil moisture sensors are essential. Radio Frequency (RF) soil moisture sensors are wireless, low-cost, and simple devices that revolutionize agriculture with real-time accuracy, advance environmental science, and promote sustainable resource management. This study aims to calibrate an innovative chip-based RF sensor using the gravimetric method for moisture content detection. Sensor calibration will be performed for sandy and loamy soils, as varying soil types affect the dielectric constant and complex permittivity measured by RF sensors. The project will explore linear and polynomial regression machine learning techniques to improve the accuracy, efficiency, and reliability of the calibration curves. A pot test with sandy and loamy soils will validate the sensor for moisture content monitoring by comparing it with a commercial moisture content device. The detection range of the sensor is calibrated and validated up to 35% moisture content. This research can demonstrate the accuracy, simplicity, affordability, and robustness of the chip-based RF sensor for soil moisture detection, contributing to the improvement of precision agricultural enhancements.
Speakers
JF

Jannatul Ferdaous Progga

North Dakota State University
Co-authors
IF

Iris Feng

North Dakota State University
SD

Shuvashis Dey

North Dakota State University
NA
SM

Srabana Maiti

North Dakota State University
NA
Thursday September 26, 2024 10:15am - 10:30am HST
Kahili

10:15am HST

WCPM 3 - Weed Control in Bell Pepper after Herbicide Application in a Reduced Sunnhemp Cover Crop Population.
Thursday September 26, 2024 10:15am - 10:30am HST
Sunnhemp cover crop seed germination can be lowered due to poor seed quality, incorrect planting depth, or adverse weather effects. The objective of this research is to evaluate weed control by herbicides in a reduced sunnhemp population. Research trials were conducted at the Plant Science Research and Education Unit, Citra, Florida, and the Syngenta Vero Beach Research Center, Vero Beach, FL. The treatments were sunnhemp at 44.83 kg/ha, sunnhemp at 22.4 kg/ha ( no herbicide, bentazon at 1.12 kg/ha, sulfentrazone at 0.14 kg/ha, halosulfuron at 0.04 kg/ha, glyphosate at 5.5 kg/ha followed by glyphosate at 5.5 kg/ha, and oxyfluorfen at 0.56 kg/ha), and a nontreated weed fallow. Sunnhemp was planted in Citra on July 18, 2023 and in Vero Beach on July 27, 2023; herbicides were applied 2 weeks after planting when the sunnhemp were 15 to 25 cm tall. After 8 weeks of growth, the sunnhemp was mowed and the field was prepared for laying plastic and planting bell pepper. The oxyfluorfen caused significant injury to the sunnhemp; this treatment had similar broadleaf, grass, and nutsedge populations to the weed fallow. In Citra at 14 and 28 days after application, bentazon, sulfentrazone, or halosuluron had lower populations than sunnhemp at 22.4 kg/ha alone, but at cover crop termination all the cover crop treatments had similar nutsedge control. All cover crop alone and cover crop herbicide treatments had similar grass and broadleaf control at crop termination. In the bell pepper crop at Vero Beach, oxyfluorfen had greater nutsedge populations than all the other treatments. Crop yields were similar among the cover crop alone or with a herbicide. The application of a herbicide in a reduced cover crop population is not necessary for increased weed control in a fall cash crop. However, the reduced cover crop population in this study was artificially created so the sunnhemp population was equal spaced through the entire plot. If the sunnhemp is significantly impacted like the oxyfluorfen treatment, then more intense recovery action may be necessary.
Speakers
PD

Peter Dittmar

University of Florida
Co-authors
DD

Devin Davis

University of Florida
NA
Thursday September 26, 2024 10:15am - 10:30am HST
Lehua Suite

10:29am HST

Plant Biotechnology 3 (PB 3)
Thursday September 26, 2024 10:29am - 11:45am HST
Leaf Culture and Regeneration in Two Cultivated Strawberries (Fragaria x ananassa) - Kedong Da
Leaf Culture and Regeneration in Hydrangea Macrophylla - Kedong Da
Immature Embryo Germination of Camellia sinensis (L) O. Kuntze. - Sarita Paudel
Development of an In Vitro Transformation System for Gene Editing Powdery Mildew Resistance in Gerbera jamesonni - Heather Gladfelter
Declining Phosphorus Availability Increases Sucrose Synthase Activity and Storage Root Formation in Sweetpotato cv Beauregard Adventitious Roots - Marissa Barbosa


Moderator
HG

Heather Gladfelter

University of Georgia
Thursday September 26, 2024 10:29am - 11:45am HST
Nautilus 1

10:30am HST

CE 5 - Drought Stress Responses of North American Native Bog Birch and Sweetgale in a Sensor-automated System
Thursday September 26, 2024 10:30am - 10:45am HST
Climate change in the Northern United States is causing less consistent rain events that pressure horticulturists to mitigate the negative impacts of drought stress in ornamental plants. Selecting ornamental native plants that can adapt to predicted changes in climate is a way to preserve and strengthen landscape biodiversity and resilience. Bog birch (Betula pumila) and sweetgale (Myrica gale) are native, colony-forming shrubs indigenous to bogs across the Northern regions of North America with aesthetic features that merit their introduction as ornamental plants. The successful introduction of wetland plants into the nursery industry depends upon their tolerances to variation in water availability typical of managed landscapes. Our 8-week study assessed physiological responses to gradual declines in substrate volumetric water content (VWC) for both shrubs, as water stress intolerance may be a constraint in horticultural landscapes. To model a severe water deficit, we built an automated irrigation system using Arduino microcontrollers connected to soil moisture sensors and solenoid valves that allowed us to track and control VWC. Control plants were maintained at 40% throughout the 8-week period, while drought was simulated by decreasing VWC by 5% each week. Water potential, stomatal conductance, and rate of leaf photosynthesis declined in the plants experiencing drought, with symptoms of leaf dieback and yellowing. In contrast, plants held at 40% VWC maintained physiological functions and had minimal aesthetic decline. By week 8, droughted bog birch and sweetgale reduced their leaf dry masses by 20% and 28%, respectively, relative to control plants. Plants held at 5% VWC had lower stomatal conductance and photosynthetic rates compared to those held at 40%, with sweet gale showing a steeper decline compared to bog birch. During the experiment, stomatal conductance of drought-stressed bog birch and sweetgale decreased by 93% and 77% respectively, and increased for control plants. Similarly, bog birch and sweetgale experienced photosynthetic declines, with respective average decreases of 68% and 62%. At the end of the experiment bog birch maintained a higher leaf retention after severe drought. Most plants of both species retained some living leaf tissue under severe drought. Despite their natural habitats in waterlogged areas, bog birch and sweetgale have potential as drought tolerant, native ornamental shrubs for gardens and landscapes.
Speakers
JH

Jessica Hutchinson

University of Maine
Co-authors
BP

Bryan Peterson

University of Maine
SB

Stephanie Burnett

University of Maine
NA
Thursday September 26, 2024 10:30am - 10:45am HST
South Pacific 3

10:30am HST

FRBR 1 - High-Density Linkage Mapping and Identification of Quantitative Trait Loci Associated with Leaf-Scab Resistance in Pecan
Thursday September 26, 2024 10:30am - 10:45am HST
Genetic maps are essential tools for gene positional cloning and marker-assisted breeding. A pecan mapping population of 119 F 1 trees was derived from a cross of the widely planted cultivars Pawnee and Elliott. Whereas ‘Pawnee’ is susceptible, ‘Elliott’ has long- standing resistance to pecan scab caused by the fungal pathogen Venturia effusa. Molecular markers were developed using genotyping-by-sequencing, and linkage maps were constructed for each parent following the two-way pseudo-test-cross strategy used for cross-pollinated species. The ‘Pawnee’ and ‘Elliott’ maps contain 1,347 and 1,050 single nucleotide polymorphism markers spanning a genetic distance of 4,493.0 and 3,758.4 cM, respectively. While these map lengths are likely inflated due to genotyping errors, a high level of synteny between genetic and physical distances of the markers in both parental maps was achieved. Scab resistance was evaluated through controlled inoculations in the greenhouse using two scab isolates, and a significant quantitative trait locus (QTL) for scab resistance was identified on chromosome 5 in ‘Elliott’. Candidate gene searches within the 2-logarithm of the odds interval of the scab-resistant QTL identified a number of disease resistance related genes, including genes encoding wall-associated receptor kinases, cytochrome P450s, leucine-rich repeats receptor-like serine/threonine-protein kinases, a pectinesterase inhibitor, a cellulose synthase, a flavonol synthase, a 4-coumarate-CoA ligase, a caffeic acid 3-O-methyltransferase, and a MYB domain transcription factor.
Speakers
GB

Gaurab Bhattarai

USDA Southeastern Fruit and Tree Nut Research Laboratory
NA
Co-authors
CB

Clive Bock

USDA Southeastern Fruit and Tree Nut Research Laboratory
NA
CP

Cristina Pisani

USDA Southeastern Fruit and Tree Nut Research Laboratory
NA
NB

Nolan Bentley

University of Texas at Austin
NA
PC

Patrick Conner

University of Georgia
SC

Shanshan Cao

University of Georgia-Tifton Campus
NA
Thursday September 26, 2024 10:30am - 10:45am HST
South Pacific 1

10:30am HST

ORGH 2 - HydroMulcH2O: A Novel, Certifiably Organic, Biodegradable Mulch Technology for Northern Highbush Blueberries
Thursday September 26, 2024 10:30am - 10:45am HST
Utilizing single-use polyethylene (PE) mulch in agriculture is controversial due to concerns with plastic waste generation and pollution. An alternative option to PE mulch is hydromulch (HM), which is paper-based, biodegradable, and potentially could be certified organic. HMs can be produced from water, recycled paper, and organic-approved tackifier(s). The objective of this experiment was to determine the efficacy of different HM formulations on yield, fruit quality, mulch coverage, and weed suppression in a mature planting of northern highbush blueberry (Vaccinum corymbosum ‘Valor’) grown in eastern Washington. Using a randomized complete block design with four replications, four mulch treatments were tested: (i) HM with 4% guar gum, (ii) HM with no tackifier, (iii) paper mill slurry, and (iv) woven PE mulch (hereafter “weedmat”). The papermill slurry was made by agitating recycled paper with water and sodium hydroxide until the paper was pulped and ink removed. Yield, fruit firmness, titratable acidity as percent citric acid, total soluble solids, and pH were similar across all treatments. Mulch coverage measured as percent soil exposure was greatest for the slurry, followed closely by the 4% tackifier and no tackifier treatments. Weedmat had the lowest percent soil exposure. All treatments mostly suppressed dicot weeds, however, the no tackifier and slurry treatments had the greatest dicot numbers. The 4% tackifier suppressed nearly all dicots. HMs struggled to suppress monocots, with the slurry and no tackifier treatments performing the worst at monocot suppression. The 4% tackifier treatment was better than the other HM formulations, however, it had little-to-no effect on nutsedge (Cyperus esculentus) while weedmat suppressed all monocots. Weed biomass data revealed different patterns with the 4% tackifier treatment having similar weed biomass compared to the slurry and no tackifier treatments. This was likely due to lack of competition, as when weeds penetrated the 4% treatment they did not have other plants to compete with, and thus accrued biomass much faster than weeds in the slurry and no tackifier treatments. Although weed and fruit quality was maintained, future research should focus on increasing HMs ability to suppress nutsedge and other vigorous weed species.
Speakers
BW

Ben Weiss

Washington State University
Ben is from Philadelphia and has been interested in food systems since an early age. He attended his first natural products expo before kindergarten because his parents worked in the natural foods industry. During late adolescence, he started a prolific tomato garden that blossomed... Read More →
Co-authors
AF

Alice Formiga

Oregon State University
NA
AD

Andrew Durado

Montana State University
NA
BM

Brian Maupin

Washington State University
NA
DB

Dilpreet Bajwa

Montana State University
NA
GG

Greta Gramig

North Dakota State University
NA
LD

Lisa DeVetter

Washington State University
NA
SW

Sharon Weyers

USDA, ARS
NA
SG

Suzette Galinato

Washington State University
NA
WA

Waqas Ahmad

North Dakota State University
NA
Thursday September 26, 2024 10:30am - 10:45am HST
South Pacific 4

10:30am HST

PB 3 - Leaf Culture and Regeneration in Two Cultivated Strawberries (Fragaria x ananassa)
Thursday September 26, 2024 10:30am - 10:45am HST
Strawberry (Fragaria × ananassa) holds significant commercial importance as a fruit crop. Tissue culture regeneration techniques offer a promising avenue for rapid propagation, genomic study, and biotech breeding, including genome editing and genetic transformation. However, literature reports on cultivated variety-based strawberry regeneration and transformation/genome editing is limited. This study aims to investigate the influence of various tissue culture conditions on the regeneration efficiency of two major cultivated strawberry varieties, 'Chandler' and 'Festival', by assessing the impact of different culture conditions and hormonal treatments on the regeneration of selected varieties' in vitro leaf cultures. The first three open leaves from 4-week-old in vitro cultures were collected and cultured on Murashige and Skoog (MS) medium supplemented with varying concentrations of Thidiazuron (TDZ) (0, 0.5, 1, 2, 4 mg/L) combined with 2,4-dichlorophenoxyacetic acid (2,4-D) (0.2 mg/L). The cultures were maintained in a growth chamber with varying light (dark/light) and photoperiod conditions. Regeneration parameters, including regeneration rate, regeneration number, and root development, were recorded over an 8-week period. Preliminary results indicate a significant influence of TDZ concentrations and light conditions on shoot regeneration rate and number. The combination of TDZ at 1 mg/L and 2,4-D at 0.2 mg/L under a 20-day dark pretreatment followed by a light (16/8-hour) condition resulted in the highest regeneration efficiency. Rooting was observed when the cultures were transferred to a hormone-free MS medium.
Speakers
KD

Kedong Da

North Carolina State University
Director of plant transformation lab at North Carolina State University
Co-authors
AN

Anna Nelson

NC State University
NA
CS

Calyssa Stevenson

North Carolina State University
NA
EK

Ezra Kinsch

North Carolina State University,
NA
GF

Gina Fernandez

NC State University
NA
HL

Huani Leng

North Carolina State University
NA
KM

Keren Molina Morale

NC State University
NA
SM

Sydney McLennan

North Carolina State University
NA
TY

Tianbao Yang

USDA-ARS
NA
WL

Wusheng Liu

North Carolina State University
Thursday September 26, 2024 10:30am - 10:45am HST
Nautilus 1

10:30am HST

PNM 2 - Soil Amendments Alter Soil Chemical Properties and Toxic Elements Accumulation in Sweetpotato cvs. Bayou Belle and Beauregard
Thursday September 26, 2024 10:30am - 10:45am HST
Field trials were conducted to investigate the feasibility of applying commonly used soil amendments to reduce the accumulation of arsenic (As), cadmium (Cd), and lead (Pb) in sweetpotato storage roots. The cultivars Bayou Belle and Beauregard were grown on an experimental site with natural levels of As, Cd, and Pb. The following soil amendments were used: agricultural lime (AGL) (1 t·ac−1), gypsum (GYP) (1 t·ac−1), biochar (BIO) (1 t·ac−1), and silicon provided as wollastonite (WOL) (2.5 t·ac−1). Compared to the unamended plots, WOL and GYP were associated with elevated soil pH and sulfur levels while reducing Mn and Fe availability. There were no differences in storage root yield grades for both cultivars. The soil amendments were associated with reducing As and Cd extractability by 12 to 31% and 2 to 5%, respectively. A notable finding was the increase in Cd and Pb accumulation in the cultivar Beauregard amended with WOL. We hypothesize that the elevated pH was associated with reducing available binding sites and surface complexes such as with Mn and Fe, leading to the increased bioavailability of Cd and Pb. These preliminary findings support the hypothesis that AGL is a viable soil amendment under mixed toxic element conditions, reducing Pb accumulation without increasing the uptake of other toxic elements. The data also support the need for a systems-based approach for the long-term management of toxic elements in sweetpotato, where soil amendment application is integrated with the use of cultivars associated with low accumulation of specific toxic elements.
Speakers
MA

Mae Ann Bravo

Louisiana State University
Co-authors
AV

Arthur Villordon

Louisiana State University
BT

Brenda Tubana

Louisiana State University
NA
CG

Cole Gregorie

Louisiana State University
NA
DL

Don La Bonte

Louisiana State Univ
NA
LA

Lisa Arce

Louisiana State University
MB

Marissa Barbosa

Lousiana State University
MA

Mary Ann Munda

Louisiana State University
Thursday September 26, 2024 10:30am - 10:45am HST
Coral 1

10:30am HST

POM 3 - The Biological Mechanism Behind Early and Late Apple Sports
Thursday September 26, 2024 10:30am - 10:45am HST
Somatic mutations in apple commonly develop into viable bud sports for cultivation. When an apple bud sport has a desirable attribute such as improved color, size, shape, flavor, firmness, sweetness, or harvest timing, it has potential to be introduced as a new cultivar that growers utilize, and consumers enjoy. The genetic mutations and related mechanisms associated with early or delayed maturation (respectively resulting in early or late harvest date) in apple sports are not known despite their value to the industry. By acquiring knowledge about these genetic mutations and their respective molecular mechanisms, breeders can identify markers to conduct more informed crosses to select for early or late maturing apple lines. Apple lines with differing developmental rates resulting in differing ‘designed’ harvest windows would optimize the deployment of field laborers for the apple harvest and improve use of cultural practices to influence harvest time. Comparison of physiology-based markers of fruit developmental stages for apple sports with different maturation dates has been done, but, to the author’s knowledge, not on trees for which crop load has been appropriately adjusted to eliminate its effect on developmental rate. In this study, crop load was regulated on 6 different apple cultivars according to tree trunk cross-sectional area. The sports selected were the ‘Gala’ sport ‘Autumn Gala’ also known as ‘Harry Black’, the early maturing ‘Fuji’ sport ‘September Wonder Fuji’, and the early maturing ‘Cripps Pink’ (‘Pink Lady®’) sport ‘Maslin Cripps Pink’. These three sports were compared to their progenitor/standard harvest time cultivar. Apple fruits were measured on each of five trees per cultivar, and volumetric growth rate was analyzed. We found that in each comparison, fruit growth rate of the early variant was significantly greater early in fruit development, roughly coinciding with the expected conclusion of the cell division phase based on phenology. Consequently, a narrower window of genetic events responsible for the early or late harvest timing phenotype has been captured. Our work confines the search for genetic events responsible for the harvest date mutations to the early developmental stages for apple fruit. We propose that harvest date in these apple bud sports is physiologically predetermined from the very early stages of fruit development and very likely not a function of strictly ripening-related processes.
Speakers
AE

Alexander Engelsma

Michigan State University
Co-authors
BW

Berkley Walker

Michigan State University
CH

Courtney Hollender

Michigan State University
NA
MT

Mauricio Tejera-Nieves

Michigan State University
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Thursday September 26, 2024 10:30am - 10:45am HST
South Pacific 2

10:30am HST

TECH 2 - Development and Demonstration of a Sensor-Based Method for Monitoring Container Substrate Fertility
Thursday September 26, 2024 10:30am - 10:45am HST
Substrate electrical conductivity (EC) measurement is a required Best Management Practice (BMP) for the application of supplemental fertilizers in Florida nursery and greenhouse industries to protect and conserve water resources. The current method of measuring substrate EC is through the Pour-through (PT) procedure, a multi-step method in which representative plants are selected for EC measurement, and a predetermined volume of water is poured on the surface of each test plant. The resulting leachate is collected and EC is determined using an EC meter. This process can be extensive for large-scale nursery production zones, requiring a significant amount of time and manual labor. With the personnel shortages that exist in production nurseries, technologies are needed to improve and optimize EC measurement and recordkeeping so the BMP is effective. This project aims to develop a new, sensor-based method for measuring EC to reduce the time invested by producers compared to the current PT method and provide real-time information on the fertility status of container-grown plants. To achieve this goal, a variety of low-cost, soil-based EC sensors were selected for measuring container substrate EC. Laboratory tests were conducted to evaluate the impact of various environmental parameters on sensor performance and select an optimal sensor for use in this application. A sensor system was designed for field deployment and wireless communication was established to monitor sensor data remotely. A field study is currently being conducted to compare EC data obtained from the sensors to EC measurements collected manually using the PT procedure and develop a protocol for sensor deployment in nurseries. At the end of the experiment, a destructive soil sampling technique will be employed to examine salt stratification within the nursery containers and help determine optimal sensor placement in the pots. This study highlights the need for technology and data-driven methods in modern agricultural practices to address challenges such as production efficiency and personnel shortages.
Speakers
ME

Michelle Ezequelle

University of Florida
Co-authors
AM

Ana Martin Ryals

University of Florida
KX

Kaiwen Xiao

University of Florida
NA
PF

Paul Fisher

University of Florida
NA
YZ

Ying Zhang

University of Florida
Thursday September 26, 2024 10:30am - 10:45am HST
Kahili

10:30am HST

WCPM 3 - Assessing the Effects of Container Sizes and Weed Densities on Weed-ornament Competition in Nursery Container Production
Thursday September 26, 2024 10:30am - 10:45am HST
Effective weed management strategies are essential for producing high-quality and successful ornamentals in nurseries and greenhouses. Weeds can affect both the productivity and quality of ornamentals, especially in containers where nutrient and moisture availability are limited, due to restricted space. The objective of this study was to determine how different types of weed species at various densities and in different container sizes affect the growth of ornamental plants. Two rounds of greenhouse experiments were conducted at the Horticulture Teaching and Research Center, Michigan State University, in summer and fall 2023. Seeds of large crabgrass {Digitaria sanguinalis (L.) Scop} and smooth pigweed (Amaranthus hybridus L.) were grown separately until they attained the 4-6 leaf stage. Liners of hydrangea {Hydrangea macrophylla (Thunb.) Ser.} and syringa (Syringa vulgaris L.) were planted in containers of three different sizes 0.67 gallons (2.54 liters), 1.5 gallons (5.67 liters), and 3 gallons (11.35 liters) containing standard bark-based substrate amended with controlled-release fertilizer. All plants received 0.5 inches (1.3 cm) of water thrice daily and were allowed to grow till they were well established. Then the weed seedlings of large crabgrass and smooth pigweed were carefully transplanted to each container-grown ornamental plant at different densities of 0,1,3,6 per pot, with the density of 0 being the control set. After weed transplantation, all pots were maintained inside the greenhouse for 8 weeks. The experimental design utilized a randomized complete block design with six replications per treatment. Initial and final growth indices of ornamentals were recorded. At 8 Weeks After Potting (WAP) fresh weights of both the weed species and the ornamentals were recorded separately. All data were analyzed in SAS by ANOVA and the Tukey’s HSD test were performed to separate out the means. Results showed that final growth indices of hydrangea were significantly higher than syringa and maximum in 3-gallon containers. Overall, large crabgrass at density of 6 was more competitive than smooth pigweed and hydrangea performed better than syringa in 3-gallon container size in competing the weed species.
Speakers
DS

Debalina Saha

Michigan State University
Co-authors
GA

Greeshmanth Alluri

Michigan State University
Thursday September 26, 2024 10:30am - 10:45am HST
Lehua Suite

10:45am HST

CE 5 - Effects of Plant Growth Promoting Rhizobacteria on Yield of Amaranth viridis Linn. Grown in a Growth Chamber and Greenhouse
Thursday September 26, 2024 10:45am - 11:00am HST
Amaranth viridis Linn. (amaranth), commonly referred to as Callaloo, is highly nutritious, drought tolerant, and require few inputs to grow. Amaranth is also known to have pharmacological properties. However, this crop is susceptible to pest damage, which hinders the crops growth, development, and marketable yield. Plant growth promoting rhizobacteria (PGPR) are naturally occurring soil microorganisms that live in the rhizosphere, aggressively colonize plant roots, and provide many benefits to plants. PGPR can promote plant growth, improve plant tolerance to biotic and abiotic stresses, increase nutrient and water uptake, and cause induced systematic resistance. This study was conducted to investigated the application of PGPR on yield and development of amaranth grown in a growth chamber and greenhouse. The study was conducted at the University of Maryland Eastern Shore Agricultural Experiment Station in a complete randomized design with four treatments (T1: Control, T2: Strand 209 (single strand), T3: Blend 5 (double strand), T4: Blend 8 (triple strand)), and six replications in the growth chamber study and nine replications in the greenhouse studies. One growth chamber study (duration for 5 weeks) and three greenhouse studies (summer 2022, fall 2022, and summer 2023) were conducted for ten weeks. Amaranth shoots grown in the greenhouse were harvested biweekly, and fresh weight and dry weight were measured. In both PGPR studies, height data and chlorophyll content were collected weekly, and fresh and dry weight of the whole plant (shoots and roots) were collected at the final harvest. Blend 5 was shown to significantly increase shoot growth when compared to the other treatments in the growth chamber study. In the 2022 summer greenhouse, Strand 209 and Blend 8 significantly increased root biomass, while Blend 5 significantly increased fresh weight of the whole plant. In the 2023 summer study, Strand 209 was significantly higher in average shoot dry weight and whole plant fresh weight when compared to the other treatments. The results of both studies showed that the application of PGPR increased amaranth growth and development. Future studies will evaluate the effects of the PGPR on systemic resistance of amaranth against the pigweed beetle.
Speakers
ZW

Zachary Williams

University of Maryland Eastern Shore
Co-authors
CC

Corrie Cotton

University of Maryland Eastern Shore
SZ

Simon Zebelo

University of Maryland Eastern Shore
NA
Thursday September 26, 2024 10:45am - 11:00am HST
South Pacific 3

10:45am HST

FRBR 1 - Genome Wide Association Studies Unmasks Loci Associated With Fruit Size and Sugar Content in Mango
Thursday September 26, 2024 10:45am - 11:00am HST
Mango (Mangifera indica L.) is a popular fruit produced widely along tropical climates for fresh consumption. In this study, mature fruits from a collection of 189 mango cultivars were evaluated for fruit weight and sugar content at horticultural maturity. Subsequently, a total of 10958 single nucleotide polymorphisms (SNPs) generated through genotyping by sequencing (GBS) were used to identify quantitative trait nucleotides (QTNs) associated with fruit weight and sugar content through genome wide association studies (GWAS). Fruit weight over three seasons averaged 454 g. ‘Lancetilla’ and ‘Webber’ cultivars produced the heaviest fruits averaging 1127.5 g and 1108.5 g respectively and the lowest average fruit weights (166.16 g, 184.5 g, and 189.5 g) were observed in ‘Itamaraca’, ‘13-1' and ‘Fralan’ cultivars respectively. The mango cultivars had a mean degrees Brix (°Bx) value of 14.8 with ‘Venus,’ ‘Peach Cobbler’ and ‘Julie’ displaying the highest degrees Brix (°Bx) values of 25.6, 22.4 and 20.6 respectively. Three QTNs in chromosomes 5, 8 and 10 were significantly associated with fruit weight using Fixed and random model Circulating Probability Unification (FarmCPU) association model, while two QTNs in chromosome 2 and chromosome 20 were significantly associated with sugar content using Bayesian-information, Linkage-disequilibrium Iteratively Nested Keyway (BLINK) model. Genetic characterization of loci associated with these two traits in mango provides a solid foundation for SNP marker assisted selection (MAS) to accelerate molecular screening of segregating populations and germplasm in a mango breeding program.
Speakers
VN

Vincent Njung'e Michael

University of Florida
Co-authors
AC

Alan Chambers

University of Florida
NA
JC

Jonathan Crane

University of Florida
RD

Rebekah Davis

University of Florida
NA
XW

Xingbo Wu

University of Florida
NA
Thursday September 26, 2024 10:45am - 11:00am HST
South Pacific 1

10:45am HST

ORGH 2 - Effect of Plastic Mulch, Living Mulches and Cover Crops on Soil Characteristics, Weed Pressure and Yield in Organic Globe Artichokes Production
Thursday September 26, 2024 10:45am - 11:00am HST
: Standard organic farming production practices for specialty crops frequently involve the use of polyethylene plastic mulch or mechanical soil disturbance to reduce weed competition and enhance crop yields. Although successful, these practices come with environmental consequences, including soil pollution and loss of soil organic matter. As such, alternative methods that prioritize the long-term health of the soil and minimize environmental impact are needed. We performed a field experiment to assess and compare the influence of five soil management systems on soil characteristics, weed pressure and yield in globe artichokes production. Artichoke (Cynara scolymus L.) seedling cvs. Tavor were established on raised beds as: A) intercropped with white clover (Trifolium repens L.) as living mulch, or B) intercropped with crimson clover (Trifolium incarnatum L.) as living mulch, or C) transplanted into mixture of buckwheat (Fagopyrum esculentum M.) and pea (Pisum sativum L.) cover crop residue or D) intercropped with Kurapia (Lippia Nodifera L.) as living mulch, or E) transplanted in PE plastic mulch. Results show that white clover increased soil organic matter (SOM), soil potassium and manganese content, water extractable carbon, soil respiration (CO2), soil nitrate, ammonium and total soil nitrogen compared to plastic mulch at 360 DAS (Days After Seeding). White clover weed suppression ability did not differ from crimson clover and buckwheat/pea mixture. Crimson clover increased SOM at preharvest sampling. Both clovers decreased artichokes yield per plant when compared to plastic mulch. Kurapia increased soil sodium content compared to plastic. Cover crop/reduce tillage system increased SOM at 120 DAS compared to plastic. Due to biomass decomposition, the suppression ability of this mixture decreased over time. Plastic mulch increased copper and iron soil concentration. Artichoke yield from plants grown on plastic mulch had comparable bud weight and yield to buckwheat/pea mixture and Kurapia. The potential to enhance soil nitrogen and carbon levels over a longer period of white clover makes it a valuable choice in systems aiming to improve soil fertility. Crimson clover emerges as the most promising among the clovers, exhibiting less competition compared to white clover, effective weed control, and, although the yield is lower than that achieved with plastic mulch, it maintains a well-balanced crop load. The reduced tillage system has shown promising results, successfully managing weeds adequately and allowing for a satisfactory level of production. No detrimental impact on yield were found intercropping artichokes with Kurapia and, but its effect on soil health was limited.
Speakers
AB

Arianna Bozzolo

Rodale Institute
Thursday September 26, 2024 10:45am - 11:00am HST
South Pacific 4

10:45am HST

PB 3 - Leaf Culture and Regeneration in Hydrangea Macrophylla
Thursday September 26, 2024 10:45am - 11:00am HST
Hydrangea is a genus of flowering plants that includes a diverse range of species and cultivars. These plants are known for their large, showy flower heads and are commonly grown as ornamental shrubs in gardens and landscapes. Hydrangea macrophylla, commonly known as bigleaf hydrangea, is a popular ornamental shrub in the hydrangeaceae family, well-known for its large, showy flower heads and broad leaves. Tissue culture regeneration techniques offer a promising avenue for rapid propagation, genomic study, and biotech breeding, including genome editing and genetic transformation. However, literature on hydrangea macrophylla regeneration and transformation/genome editing report is limited. This study aims to investigate the influence of various tissue culture conditions on the regeneration efficiency of Hydrangea macrophylla 'Blaumeise,' 'H2020-59,' and 'H15298' by assessing the impact of different culture conditions and hormonal treatments on the regeneration of selected varieties in vitro leaf cultures. The first three open leaves from 4-week-old in vitro cultures were collected and cultured on Murashige and Skoog (MS) medium, supplemented with varying concentrations of 6-Benzylaminopurine (BAP) (0, 0.5, 1, 2 mg/L) combined with 1-Naphthaleneacetic Acid (NAA) (0.01 mg/L). The cultures were maintained in a growth chamber with varying light (dark or light) and photoperiod conditions. Regeneration parameters, including regeneration rate, regeneration number, and root development, were recorded over a 4-week period. Preliminary results indicate a significant influence of BA concentrations and light conditions on shoot regeneration rate and number. The combination of BA at 2 mg/L and NAA at 0.01 mg/L under dark conditions resulted in the highest regeneration efficiency. Rooting was observed when the cultures were transferred to a hormone-free MS medium.
Speakers
KD

Kedong Da

North Carolina State University
Director of plant transformation lab at North Carolina State University
Co-authors
AN

Anna Nelson

NC State University
NA
CN

Callie Nix

North Carolina State University
NA
HL

Huani Leng

North Carolina State University
NA
JN

John Nix

NC State University
NA
KM

Keren Morales

NC State University
NA
SM

Sydney McLennan

North Carolina State University
NA
TR

Thomas Ranny

North Carolina State University
NA
WL

Wusheng Liu

North Carolina State University
Thursday September 26, 2024 10:45am - 11:00am HST
Nautilus 1

10:45am HST

PNM 2 - Iron Biofortification in Radish and Pea Microgreens Using Alternative Iron Sources and Ascorbic Acid
Thursday September 26, 2024 10:45am - 11:00am HST
Iron (Fe) is an essential and versatile micronutrient in plants and humans, and inadequate levels of dietary Fe can cause impaired development in children and poor physical and cognitive functioning in adults. Iron deficiency is the leading micronutrient deficiency worldwide, affecting around 1.6 billion people, with the most vulnerable demographic being pregnant women and infants. Contributing factors include diets that, particularly in developing regions, are predominantly comprised of cereal grains which are characterized by relatively low bioavailable Fe levels. Additionally, 30% of cultivated soils globally have low Fe availability. Defining effective ways to increase Fe content and availability in edible plants is therefore of utmost importance, and an agronomic approach to Fe biofortification could be a viable solution. Microgreens are an ideal candidate crop for tackling nutrient deficiencies. They are nutrient dense, have low antinutrient levels, can be grown in a relatively short amount of time, and can be consumed raw, making them a convenient target for agronomic Fe biofortification. Unfortunately, Fe uptake by plants is problematic, especially in alkaline and oxidizing conditions. Previous studies have suggested the potential of using ascorbic acid (AA) as an enhancer of Fe uptake. However, this approach has not been tested before in microgreens. Therefore, a study was conducted to investigate in a soilless system the effect of different Fe sources with and without organic acids (Ferric sulfate, Ferric sulfate 0.1% Ascorbic acid, Ferric citrate), applied via fertigation at different concentrations (0, 15, 30, 45 mg/L of Fe), on radish and pea microgreens’ Fe content. Treatments were arranged in a randomized factorial experimental design using three replications. We discovered that Ferric sulfate 0.1% AA was the most effective source in increasing Fe uptake, while Ferric citrate was the least efficient. Fertigating with 45 mg/L Ferric sulfate with 0.1% AA resulted in an approximately 110% increase in Fe accumulation in radish and pea microgreens, compared to the untreated control. However, using sodium hydroxide (NaOH) to adjust the nutrient solution pH, the same treatment was associated with an increased level of Na and resulted in a 3-30% reduction in fresh and dry biomass in both microgreen species. In conclusion, this study provides promising evidence that through fertigation, supplementation of AA with Fe fertilizers is effective in increasing Fe uptake in two microgreens species. However, careful consideration of Fe sources and concentrations needs to be made to not compromise yield and nutritional quality.
Speakers
RR

Rishi Ravichandran

Student, Pennsylvania State University
Co-authors
BN

Benedikt Nuesslein

Pennsylvania State University
NA
EC

Erin Connolly

Pennsylvania State University
NA
FD

Francesco Di Gioia

Pennsylvania State University
Thursday September 26, 2024 10:45am - 11:00am HST
Coral 1

10:45am HST

POM 3 - Characterizing Unique Apple Selections for U-Pick Growers in the Midwest Using Descriptive Analysis, Consumer Liking Tests, and Phytochemical Analysis
Thursday September 26, 2024 10:45am - 11:00am HST
The apple U-Pick market in Ohio lacks diversity in varieties to meet consumer demand outside of those typically available at grocery stores. Apple growers want new cultivars that are suited for growth in the Midwest, ripen across the picking season, and intrigue customers with unique flavors, textures, and traits. These diverse and unique tasting apples exist, but it is difficult to market these apples without a comprehensive understanding of the traits and consumer desirability of these fruits. This project aims to identify and characterize sensory traits in 33 up-and-coming apple selections including commercial, in-development, and wild varieties with novel characteristics suited for local production. Apple selections were chosen in conjunction with apple specialists at The Ohio State University and local apple growers. Consumer perception and apple traits were evaluated through two sets of sensory experiments: consumer hedonic testing and descriptive analysis. Consumer testing was conducted in private sensory booths, where apple slices were provided in a randomized, blinded order to mitigate order effects. One hundred participants rated apples on their appearance, texture, flavor, and overall liking on a 9-pt hedonic liking scale (i.e., dislike extremely to like extremely). Descriptive analysis was conducted by 12 trained panelists who used references as anchors on a 10-pt scale to score important appearance, aroma, flavor, and texture fruit characteristics. Measured characteristics were decided in collaboration with the panel organizer, trained panelists, and included traits of particular interest to growers. The trained panelists rated 26 traits like red color, floral notes, sweetness, and crispness. Anchors were carefully selected to provide precise references along the scale, such as sucrose solutions of varying concentration to calibrate judgements of sweetness. To compare how different factors of the apple related to each other, correlation analyses were run on the datasets. Flavor liking had the strongest positive correlation with overall liking, followed by texture liking, while appearance liking showed a weaker positive correlation. Sweetness exhibited a slight positive correlation with overall liking, whereas sourness showed the opposite. Using mean separation tests, we identified 15 apple selections liked equivalently to Honeycrisp, a top commercial apple. Further phytochemical analysis will enable gaining insights on nutritional quality profile and its relation to consumer preference. Our goal is to provide information on novel apples that will enable apple growers to diversify their offerings, which will also benefit producers and consumers.
Speakers
LB

Lydia Balogh

PhD Student, The Ohio State University
Co-authors
CS

Christopher Simons

The Ohio State University
NA
DM

Diane Miller

The Ohio State University
NA
JC

Jessica Cooperstone

The Ohio State University
NA
JF

Jonathan Fresnedo Ramirez

The Ohio State University
NA
Thursday September 26, 2024 10:45am - 11:00am HST
South Pacific 2

10:45am HST

TECH 2 - Enhancement of air quality in agricultural facility using particulate matter reduction systems
Thursday September 26, 2024 10:45am - 11:00am HST
In agricultural facility, which are equipped with mechanical and closed ventilation systems, have faced the challenge to reduce fine dust concentration for enhancing working environment. Among the dust sources, fruit fuzz, characterized by its dense and needle-like structure, can induce allergic symptoms in agricultural workers upon exposure to their respiratory systems and skin, adversely impacting their health and deteriorating the work environment. The focus of this research is the development of a fine dust reduction system aimed at enhancing the working conditions. The system operates by generating a downward airflow to prevent fine dust from reaching the workers' respiratory systems. To assess the efficacy of the fine dust reduction system, real-time measurements of dust concentrations were conducted at commercial peach sorting stations, both before and after the operation of this system. The findings revealed that during peach sorting task, the total dust concentration was 6.89 times higher than the normal condition, representing the critical need for reducing fine dust levels. The deployment of a particulate matter reduction system specifically within the fruit sorting area, a section identified for substantial dust generation due to the removal process of fruit covering bags, has led to a substantial decrease in airborne particulate concentrations. This targeted intervention resulted in an 80.4% reduction in Total Suspended Particulate (TSP) levels and a 60.3% decrease in PM-10 concentrations at the site of implementation. Additionally, a broader assessment across the entire sorting facility revealed a significant decline in fine dust levels, with TSP concentrations diminishing by 67.6% and PM-10 concentrations by 52.2%. This research underscores the efficacy of targeted fine dust control measures within agricultural facilities, markedly enhancing air quality and the occupational environment for agricultural laborers.
Speakers
HS

hyojae Seo

Department of Rural Construction Engineering, Jeonbuk National University
Thursday September 26, 2024 10:45am - 11:00am HST
Kahili

10:45am HST

WCPM 3 - Herbicide-Resistant Italian Ryegrass in Oregon Hazelnut Orchards: Evaluating Nonchemical and Chemical Methods
Thursday September 26, 2024 10:45am - 11:00am HST
Herbicide-resistant Italian ryegrass (Lolium multiflorum Lam.) presents a significant challenge in hazelnut orchards across Oregon, with confirmed resistance to multiple herbicide modes of action groups (1, 2, 9, 10, 15, and 22). Four field studies were conducted in 2023 to evaluate nonchemical and chemical methods for controlling Italian ryegrass during spring. Tested treatments included mowing at 2 km h-1, electric weeding control (EWC) at 15 MJ ha-1 (2 km h-1), and glufosinate application at 1.68 kg ai ha-1, administered once or twice. Furthermore, combinations of EWC with mowing or glufosinate were examined, resulting in eleven treatments. EWC was performed using alternating current and 30 kW (EH-30 Thor, ZassoTM), treating swaths 1.2 m wide. Assessments conducted 56 days after initial treatment (DAIT) revealed that single mowing showed no significant difference compared to untreated plots. However, when mowing was performed twice, it led to a 30% reduction in inflorescence density and an 84% reduction in weight. EWC, applied once or twice, resulted in significant decreases in Italian ryegrass inflorescence density (51-58%), weight (55-73%), and shoot weight (45-75%) compared to untreated plots, with no significant differences observed between single or double applications. Similarly, glufosinate applied once or twice substantially reduced Italian ryegrass inflorescence density (68 to 86%) and weight (73 to 93%). Combinations of EWC with mowing or glufosinate demonstrated high efficacy, achieving control rates of 89 to 96% and exhibiting comparable efficacy to two applications of glufosinate (96%). These findings suggest that EWC, when applied during the spring period, can effectively control Italian ryegrass, offering comparable efficacy to glufosinate and superior efficacy to mowing.
Speakers
MM

Marcelo Moretti

Oregon State University
Thursday September 26, 2024 10:45am - 11:00am HST
Lehua Suite

11:00am HST

Exhibit Talk: Spectrum Technologies Inc.
Thursday September 26, 2024 11:00am - 11:15am HST
Thursday September 26, 2024 11:00am - 11:15am HST
Coral 5

11:00am HST

CE 5 - Shade-Avoidance Responses of Kale and Lettuce Elicited by Far-Red Light Can Persist Under High-Light Intensity
Thursday September 26, 2024 11:00am - 11:15am HST
Far-red (FR; 700–750 nm) light induces shade-avoidance responses such as stem and leaf elongation and an increase in specific leaf area (SLA). Previous studies have reported that a high photon flux density (PFD) can mitigate the effects of FR light. However, limited research has explored the impacts of individual waveband PFDs on the effects of high total PFD (TPFD) in regulating FR-light responses. To address this gap, we conducted an experiment hypothesizing that the effects of a high FR fraction [FR-PFD divided by the sum of red (R; 600–699 nm) and FR PFD] on shade-avoidance responses would persist when the TPFD increases were solely from increases in R and FR PFDs. We grew kale (Brassica oleracea var. sabellica) ‘Red Russian’ and lettuce (Lactuca sativa) ‘Rex’ and ‘Rouxai’ under 12 lighting treatments with a 24 h∙d−1 photoperiod, TPFDs of 85, 170, 255, or 340 µmol∙m−2∙s−1, and FR fractions of 0.00, 0.17, or 0.33. The blue (400-499 nm) PFD was constant in all treatments and the alterations in the TPFDs were solely due to R and FR PFDs. Based on preliminary results, high FR fractions increased the leaf length of kale to a similar degree at all TPFDs except for no increase at the TPFD of 85 µmol∙m−2∙s−1. High FR fractions increased the leaf length of lettuce ‘Rex’ and ‘Rouxai’ to a similar degree at all TPFDs. In contrast, the SLA of kale did not respond to the FR fraction at any of the TPFDs. The SLA of lettuce ‘Rex’ and ‘Rouxai’ was increased by high FR fractions to a similar degree at all TPFDs except for no increase at the TPFD of 85 µmol∙m−2∙s−1. Contrary to the paradigm, our results suggest that FR-fraction effects can persist under a high TPFD when R and FR PFDs are elevated. Moreover, the lack of response of kale leaf length and lettuce SLA to the FR fraction at the lowest TPFD implies that a low R and FR PFD attenuates the effect of the FR fraction in eliciting shade-avoidance responses.
Speakers
JS

Jiyong Shin

Michigan State University
Co-authors
ER

Erik Runkle

Michigan State University
NA
Thursday September 26, 2024 11:00am - 11:15am HST
South Pacific 3

11:00am HST

FRBR 1 - A Genome-Wide Association Study To Identify Loci Underlying Fruit Color In Red Raspberry
Thursday September 26, 2024 11:00am - 11:15am HST
Red raspberry (Rubus idaeus L.) is a high-value crop, acclaimed for its fruit quality characteristics and putative health benefits. Among fruit quality characteristics, color is a critical trait in determining market acceptability and consumer preference. Red raspberry fruit encompasses a wide array of colors, notably yellow, orange, and red. Red fruited cultivars are the most common in commercial settings and market selection is dependent on the color intensity: while the processing industry needs dark berries for most applications, the fresh market requires bright red and non-darkening fruit. Anthocyanins, a group of water-soluble phenolic compounds, are regarded as the major contributors to raspberry red fruit color. Knowledge on the genetics of raspberry fruit pigmentation would be valuable for breeding programs, but to date the genetic control of the different red intensities of raspberries remains elusive. This research aims to map the genetic regions underlying the red shades of raspberry fruit through a genome-wide association study (GWAS). Fruits from 765 red raspberry cultivars and selections – including red-, orange-, and yellow-fruited genotypes – were harvested over four seasons (2018-2021) and analyzed for total anthocyanin content and color. Total anthocyanins were measured through the pH differential methods and color was assessed using a high-throughput digital phenotyping protocol. Leaves from all genotypes were harvested in summer 2022 and used for genomic DNA extraction. Whole-genome sequencing of DNA samples was achieved through Illumina NovaSeq6000, with an average coverage of 30×. Sequences were aligned to the ‘Malling Jewel’ reference genome using BWA-MEM and single nucleotide polymorphisms (SNPs) were identified following the GATK pipeline. Total anthocyanin content ranged between zero (yellow genotypes) and 113.21 mg/100 g fresh weight (FW) of peonidin-3-O-glucoside equivalents (P3OG eq.) and averaged 42.09 mg/100 g FW P3OG eq. Color coordinates L* (lightness) varied between 11.99 and 48.21 and averaged 21.21, a* (red-green) spanned -1.18 and 38.38 and averaged 26.85, b* (yellow-blue) ranged between 4.57 and 30.04 and averaged 18.05. The association between the detected genetic variants and the phenotypic data (fruit color and total anthocyanins) will enable the identification of SNP markers that explain the variation in observed red shades of berries. Such markers will be used in raspberry breeding programs to facilitate the development of cultivars with desired fruit color.
Speakers
CB

Claudia Baldassi

University of British Columbia
Co-authors
MD

Michael Dossett

BC Berry Cultivar Development Inc.
NA
SC

Simone Castellarin

The University of British Columbia
NA
Thursday September 26, 2024 11:00am - 11:15am HST
South Pacific 1

11:00am HST

ORGH 2 - Eastern South Dakota Early Season Soil Tarping Impacts on Soil Microbiology
Thursday September 26, 2024 11:00am - 11:15am HST
Solarization and occultation are weed management strategies used by growers across the globe. However, there is not a large amount of literature discussing the impacts of this weed management practice on soil health. This study evaluated the impact of tarp materials and duration of tarp coverage on soil microbiology. Field experiments were conducted in the 2023 growing season in Brookings, South Dakota. Solarization was conducted using clear tarps secured with sandbags and buried edges. Clear tarps were placed early spring for six, four, and two weeks before tarp removal in May. Immediately following tarp removal, each plot was tilled, and rows of onion transplants were planted. Occultation was conducted using white side up and black side up silage tarps, both applied for six, four, and two weeks before removal and planting onions. These treatments were organized in a randomized complete block design with four blocks and ten treatment plots per block including a control with no tarp. Temperature and moisture data were taken in treatment plots using HOBO temperature and moisture sensors during tarping as well as during the growing season. Soil samples were taken before tarp application to observe organic matter and basic nutrients. Samples were also collected in each treatment plot after tarping and at the end of the growing season to determine differences in organic matter, basic nutrients, soil respiration, permanganate oxidizable carbon, and nitrogen. Solarized plots showed trends of higher temperatures during tarping compared to occultation plots. Solarized plots showed higher soil moisture trends during tarping and lower moisture trends during the growing season. Occultation tarp treatments showed trends of lower moisture during tarping and higher moisture during the growing season. No significant differences were seen between tarp treatments for soil respiration, permanganate oxidizable carbon, and nitrogen. While soil tarping can manipulate soil microbiology, more research is needed to determine the full extent of these impacts.
Speakers
HV

Hannah Voye

South Dakota State University
Co-authors
KL

Kristine Lang

South Dakota State University
RB

Rhoda Burrows

South Dakota State University
NA
Thursday September 26, 2024 11:00am - 11:15am HST
South Pacific 4

11:00am HST

PB 3 - Immature Embryo Germination of Camellia sinensis (L) O. Kuntze.
Thursday September 26, 2024 11:00am - 11:15am HST
Camellia sinensis (L.) O. Kuntze is a woody perennial, evergreen shrub or small tree native to Southwest China, whose leaves are processed into various types of teas for consumption. Harvesting mature tea seeds typically requires 12 to 14 months, with an additional 2 to 3 months needed for germination using traditional methods. In an effort to expedite this breeding cycle, we conducted aseptic germination experiments on immature embryos of Camellia sinensis fruits collected from different months, spanning from May to September. Visible embryos were observed in immature fruits harvested in late July, exhibiting an average size of 2.17 ± 0.33 cm, and demonstrated germination capabilities only after mid-August. These embryos were excised and cultured on Murashige and Skoog (MS) medium supplemented with 3% sucrose and 0.65% agar. Cultures were maintained in a growth chamber set at 24°C under a 16-hour photoperiod. To enhance the germination process, cultures were kept in darkness for the initial two weeks. Immature embryos initiated germination approximately one to two weeks after the initiation of culture. After two months, plantlets were transplanted into a substrate consisting of peat moss and perlite (1:1 v/v) and acclimatized in a mist system within a greenhouse. Five month post-culture initiation, the average shoot length, root length, and leaf number of transplanted plantlets were recorded as 2.24 ± 0.89 cm, 5.61 ± 4.58 cm, and 8.36 ± 2.84, respectively. Preliminary findings suggest promising outcomes, demonstrating the feasibility of in-vitro embryo germination in tea plants. This methodology holds the potential to mitigate late-term abortion of hybrid embryos and significantly shorten the breeding cycle, critical aspects in breeding triploid tea varieties through crossbreeding diploid and tetraploid tea plants.
Speakers
SP

Sarita Paudel

University of Georgia
Co-authors
DZ

Donglin Zhang

University of Georgia
Thursday September 26, 2024 11:00am - 11:15am HST
Nautilus 1

11:00am HST

PNM 2 - Understanding the Boron-Yield Relationship in Pistachio Orchards
Thursday September 26, 2024 11:00am - 11:15am HST
Micronutrients like boron, similar to essential macronutrients (nitrogen, phosphorus, and potassium), play a crucial role in plant growth and productivity, even though they are required in smaller quantities. In California’s pistachio production, boron deficiency was initially identified as a concern. However, more recently, the issue has shifted to excess boron in soils and water, potentially affecting the plants as boron toxicity. The current study is investigating the relationship between soil and leaf boron levels, leaf surface area damage and yield in pistachio drip irrigated orchard. Soil, leaf and yield data were collected from a second year running salinity management trial on an eight-year-old pistachio orchard (established in 2015) on the west side of the San Joaquin Valley. Our preliminary findings indicate that while soil boron levels significantly reduced pistachio yield, no significant correlation was found between leaf boron level or percentage of leaf damage (indicative of boron toxicity) and yield. This indicates that the decrease in yield with increasing soil boron is not caused by a reduction in active photosynthetic area. Based on these findings, focusing on monitoring and maintaining optimal soil boron levels might be the most effective strategy for minimizing potential yield losses associated with boron issues in pistachio orchards.
Speakers
MM

Mukesh Mehata

University of California, Davis
Co-authors
BM

Blake Mccullough Sanden

University of California Davis
NA
GB

Gary Banuelos

USDA ARS
NA
GM

Giulia Marino

University of California, Davis
NA
JC

Joseph Coehlo

Valley Orchard LLC
NA
LF

Louise Ferguson

University of California, Davis
NA
MC

Mae Culumber

University of California, Davis
NA
MS

Marta Saludes

Universidad de Salamanca
NA
Thursday September 26, 2024 11:00am - 11:15am HST
Coral 1

11:00am HST

POM 3 - Selection and Patenting of New, Grower Friendly Apple Trees by the Maryland Tree Architecture Project
Thursday September 26, 2024 11:00am - 11:15am HST
The Maryland Tree Architecture Project (MD-TAP) used classical plant breeding methods to create, identify, select and then patent grower-friendly apple trees. The project began in 1991 with the open pollination of 'McIntosh Wijcik' trees set in an isolated 'Gala' block. Elite seedlings resulting from that initial cross then served as male parents in an open-pollination of commercial cultivars well-adapted to the warm, wet, windy, Mid-Atlantic climate. Two scion-dwarfed, apple trees producing good quality fruit and demonstrating a reduced susceptibility to fire blight resulted from this effort. These two selections were patented as 'MD-TAP1' and 'MD-TAP2' in 2023. A replicated field trial was set in 2016 to compare these two scion-dwarfed selections, with their wild-type siblings also from this program. Trees were budded onto 'M.111,' a semi-dwarfing rootstock to assess their growth habit and tree size without the benefit of trellis support or sustained annual pruning. Trees were set at a 2.75 by 4.25 m (9 by 14 ft) spacing and are still manageable. Despite annual pruning, they are similar in height to trees in an adjacent tall-spindle planting budded onto dwarfing rootstocks. The University of Maryland concluded two Materials Transfer Agreements (MTAs) with other universities before the patents were allowed. After patenting, the University began contacting commercial nurseries in the Mid-Atlantic Region for future testing and licensing.
Speakers
CW

Chris Walsh

University of Maryland
Chris Walsh is a Professor Emeritus in Horticulture. He currently maintains research and educational programs in tree fruit production and apple tree breeding, and in fresh-market produce safety.
Thursday September 26, 2024 11:00am - 11:15am HST
South Pacific 2

11:00am HST

TECH 2 - Experience with New Generation Horticultural Education, Research and Production Through Indoor Ag.
Thursday September 26, 2024 11:00am - 11:15am HST
These days it has become almost impossible to depend on climate for agricultural production of any crops mainly horticultural crops. Unpredictable climate conditions have been a significant challenge to growers. Therefore, it is an urgent need for horticultural educators, researchers, and growers to come up with new approach to explore new farming techniques. This abstract is to discuss over 8 years experiences of research and education on Indoor Ag includes hydroponics with vertical, horizontal, fully automated, or partially automated farming techniques. It has enormous potential to overcome all challenges that is claimed to grow plants and global food security due to population growth, unpredictable climate, water scarcity, space, labor, and food safety related. Indoor Ag is mainly soilless, it is controlled environment agriculture (CEA). Opening educating opportunities to new generation who can come up with new innovative designs with new techniques to improve it for better. In recent times Indoor Ag has come up with very high expectation, and capable of growing plants from several hundred times more than traditional farming per year. Besides, Indoor Ag (IA) facility or controlled environment agriculture could produce the best quality crops. With the experiences in Indoor Ag along with traditional outdoor Ag, the conclusion is we need to develop education, research, and extension curricula about Indoor Ag, urgently. Indoor Ag as a new discipline it has a few challenges but could be overcome easily by our intelligent next generation students. They can take Indoor Ag education, research and production techniques as the future Horticulture. At present, globally a limited number of faculties and researchers has been involved that needed to be increased through interest and hands-on training in this new technology. It has been observed, most of the Indoor Ag is run by business owners and for business secret they cannot share their true success story to increase competition that we all agree. But we researchers who have been working for the better future to overcome multifaceted challenges can see the Indoor Ag as potential alternative. Therefore, now is the time we should adopt Horticultural education, research, and production through Indoor Ag. We need to develop academic courses, education, and research activities from K-12 to undergraduate and graduate programs in college and Universities. So, whoever involved in agricultural research and education at this moment Indoor Ag should be our goal to make it future global horticulture education, research, and production method.
Speakers
BB

BIPUL BISWAS

FORT VALLEY STATE UNIVERSITY
Thursday September 26, 2024 11:00am - 11:15am HST
Kahili

11:00am HST

WCPM 3 - Limiting Liverwort Growth by Allelopathic Effects of Organic Mulches in Ornamental Production
Thursday September 26, 2024 11:00am - 11:15am HST
Liverwort (Marchantia polymorpha) is one of the problematic weeds in ornamental crop production that deteriorates the quality and aesthetic value of ornamentals. To study the effectiveness of allelopathic properties of organic mulch extracts, six different organic mulch materials including rice hull (RH), cocoa hull (CH), pine bark (PB), maple leaf (ML), shredded cypress (SC) and red hardwood (HW) were used for obtaining mulch extracts. The extracts were prepared by following the modified EPA 1312 synthetic precipitation procedure. In the lab experiment, the mulch extracts obtained were used to impregnate agar media at an increasing dose at either 1x (2ml), 2x (4ml), 3x (6ml), and 4x (8ml) rates. Ten gemmae were transferred to the culture medium in each petri dish and all petri dishes containing gemmae were maintained inside the growth chamber. Data was recorded for number of gemmae germinating in each petri dish and at the end of experiment, the length and width of the thallus derived from each gemmae were measured. For greenhouse experiment, the mulch extracts were applied to nursery containers filled with standard substrate and amended with controlled-release fertilizer for assessing the postemergent liverwort control in nursery containers. Either RH, HW, CH, ML, SC or PB mulch extracts were applied to each of the container uniformly at either 1X (15ml), 2X (30ml), 3X (45ml), and 4X (60ml) rates, at the beginning of experiment and bi-weekly until 10 weeks. Control set without any mulch extract was included as well. Percent of substrate surface covered by liverwort thalli was visually estimated bi-weekly until 10 weeks after first treatment. Fresh biomass of the thalli and number of gemmae cups in each pot were also recorded at the end of the experiment. Both lab and greenhouse experiments had four replications per treatment and were arranged in a randomized complete block design. After 1 week in the growth chamber, ML followed by SC, PB and RH extracts showed maximum suppression of liverwort gemmae germination. At 2 weeks, all rates of ML provided complete inhibition of liverwort. In the greenhouse, all the mulch extracts were able to provide complete liverwort control for the first two weeks. PB and HW mulches showed excellent liverwort control and minimum biomass of liverwort after 10 weeks as compared to other mulches. Hence, the allelopathic potential of the organic mulches can be a promising option for biopesticidal control of liverwort, and a component of integrated liverwort management.
Speakers
MS

Manjot Sidhu

Michigan State University
Co-authors
DS

Debalina Saha

Michigan State University
Thursday September 26, 2024 11:00am - 11:15am HST
Lehua Suite

11:15am HST

CE 5 - Does Intermittent and Continuous Nutrient Flow Affect the Growth and Phytochemicals of Culinary Herbs in NFT Hydroponics
Thursday September 26, 2024 11:15am - 11:30am HST
Hydroponic cultivation has emerged as an innovative method for efficient and sustainable production of different crops because of year-round production and precise nutrient delivery. Light plays a major role when plants are grown in a controlled environment. Supplemental light is necessary for the physiological function of crops when grown in a hydroponics system. In nutrient film technique (NFT) hydroponic production, crops are usually produced with continuously flowing nutrient solutions. However, intermittent flow, where nutrient solutions are paused for periods of time instead of continuous cycling, has been proposed as a more efficient hydroponic system. Intermittent flow of nutrients increases the efficiency of hydroponic systems as it reduces the cost of running pumps continuously. Culinary herbs can be grown easily in NFT hydroponic systems. These herbs are a high-value crop and are a rich source of vitamins, nutrients, fibers, and phytochemicals that are known to fluctuate in concentration in different production systems. Yet it is not known if intermittent irrigation will impact phytochemicals in culinary herbs with or without supplemental lights in NFT production. This experiment investigated the effect of intermittent and continuous flow of nutrients in two culinary herbs, cilantro (Coriandrum sativum) and parsley (Petroselinum crispum) with or without supplemental lights. To regulate nutrient solution flow, the pump was turned on continuously in the continuous flow treatment, whereas it was turned on and off periodically for 30-minute intervals in the intermittent flow system. The herbs were grown for a month and different plant growth parameters like plant height, plant fresh weight, dry weight, root length (RL), total phenolic content (TPC), total flavonoid content (TFC) and proline were measured. Interestingly, nutrient delivery only affected plant height and plant fresh weight in cilantro. Plant height was greater in intermittent flow whereas plant fresh weight was greater in continuous flow. However, nutrient flow did not show any differences in other studied growth parameters in both herbs. Supplemental light significantly increased the root length, plant fresh weight, and dry weight of both herbs. TFC of cilantro was affected by the interaction of supplemental light and nutrient flow system with greater flavonoids in a continuous flow without supplemental light. In parsley, supplemental light increased the proline content. These findings suggest that cilantro and parsley can be grown easily in intermittent flow by reducing the associated cost of production. However, supplemental lighting is necessary to increase the yield of herbs.
Speakers
AR

Abishkar Regmi

Texas Tech University
Co-authors
CS

Catherine Simpson

Texas Tech University
NA
HL

Haydee Laza

Texas Tech University
NA
LS

Lindsey Slaughter

Texas Tech University
NA
NM

Naima Moustaid Moussa

Texas Tech University
NA
Thursday September 26, 2024 11:15am - 11:30am HST
South Pacific 3

11:15am HST

FRBR 1 - Relatedness of Luther Burbank’s Plum (Prunus sp.) Introductions based on Genotyping by Sequencing (GBS)
Thursday September 26, 2024 11:15am - 11:30am HST
The renowned horticultural artist and plant breeder Luther Burbank worked with many different species of plants. During his 50-year career, he introduced over 800 cultivars, including more than 150 accessions of plums (Prunus spp.) in the late 1800’s and early 1900’s. Burbank preferred utilizing wide, interspecific crosses to create a vast range of phenotypic variation and then artificially select from the extremes. While a very great artist, Burbank was a substandard scientist because he was derelict in pedigree note-taking. Though many of his introductions are extinct, hobbyists, enthusiasts, and international collections retain nearly a third of the economically viable cultivars he bred. For a century, many of his hybridizations remained inscrutable mysteries until modern genomic and computational tools developed their resolution and statistical power. Today, genotyping by sequencing (GBS) is a useful tool for pedigree reconstruction in the absence of reliable records. GBS can inform principal component analyses (PCA), identity by descent (IBD) kinship, and phylogenetic admixture, revealing complex relationships among taxa. In this study, whole genome sequencing was performed on 53 Prunus taxa used by Luther Burbank in his breeding experiments in the most comprehensive genetic survey of his work to date. Exact parent-offspring relationships between this population may be impossible to discern due to years of back crossing, sibling mating, and open pollination. However, the proportion of genomic similarity amongst these taxa provides information on the relatedness of the genotypes in Burbank’s Prunus experiments, defining four primary lineages within his breeding population. These lineages are comprised primarily of P. salicina and P. simonii, but also have influences from P. americana, P. cerasifera, P. domestica, and P. rivularis. The prevalence of P. simonii in Burbank’s Prunus introductions appears to have been vastly underreported, indicating that some of the seedstock founders of his breeding population could have been P. salicina x P. simonii hybrids at the inception of his career. This research has implications for pedigree reconstruction and prioritizing conservation in collections curation for future studies.
Speakers
avatar for Rachel Spaeth

Rachel Spaeth

Research Horticulturalist, USDA-ARS-NCGR-Davis
Dr. Rachel Spaeth is currently serving as a postdoc with the USDA-ARS-NCGR as the Interim Curator of the Prunus collection. Prior to that she was the Curator at the Luther Burbank Home & Gardens in Santa Rosa, CA for 15 years.  She is the co-host on KSRO's Garden Talk Radio two Saturdays... Read More →
Co-authors
DP

Daniel Potter

University of California at Davis
NA
DP

Domininque Pincot

University of California at Davis
NA
JP

John Preece

USDA-ARS-NCGR Emeritus
NA
PJ

Pat J Brown

University of California at Davis
NA
TG

Tom Gradziel

University of California at Davis
Thursday September 26, 2024 11:15am - 11:30am HST
South Pacific 1

11:15am HST

PB 3 - Development of an In Vitro Transformation System for Gene Editing Powdery Mildew Resistance in Gerbera jamesonni
Thursday September 26, 2024 11:15am - 11:30am HST
Gerbera is among the significant players in the global cut flower market, valued at 30 billion USD in 2023. Gerbera daisies, along with chrysanthemums are the largest segment of the cut flower market with a share of 40%. The quality and quantity of gerbera cut flower production is negatively impacted by the fungal disease powdery mildew causing a significant loss of revenue. Effects from powdery mildew infection include reduced flower quality, stunted growth, decreased flower longevity, and decreased marketability. Powdery mildew is currently controlled using fungicides which increases the cost of cut flower production and has the potential for the fungus to develop resistance to the fungicides. One strategy is to use gene editing and CRISPR technology to produce gerbera plants resistant to powdery mildew. The gene “mlo” which stands for “Mildew Locus O” plays a crucial role in the plant’s defense against powdery mildew infections. Plants with mutations in the “mlo” gene exhibit a type of broad-spectrum resistance providing protection against various strains of powdery mildew. We developed a tissue culture regeneration and transformation system for the Gerbera jamesonii cultivar ‘Flori Line Maxi Yellow’ which is sensitive to powdery mildew. The Agrobacterium tumefaciens strain GV3101 containing a binary plasmid encoding for an enhanced GFP marker gene and hygromycin selection gene was used to develop the transformation system. Young, 10mm sized in vitro leaves with part of the petiole were used as explants. A sensitivity test with the explants showed hygromycin at 7.5 mg/L was optimal for selection of callus with positive GFP expression. The next step is to regenerate GFP plants to confirm successful transformation and design CRISPR constructs to inactivate the “mlo” gene in the powdery mildew sensitive gerbera cultivar via gene editing.
Speakers
HG

Heather Gladfelter

University of Georgia
Co-authors
DW

Dayton Wilde

University of Georgia
NA
KT

Khuram Tanveer

University of Georgia
NA
Thursday September 26, 2024 11:15am - 11:30am HST
Nautilus 1

11:15am HST

POM 3 - Effects and Interactions of Water Stress and Rootstock on Physiological Responses and Ambrosia Beetle Colonization of Apple Trees
Thursday September 26, 2024 11:15am - 11:30am HST
Rapid apple decline (RAD), a phenomenon that causes sudden decline and death of young apple trees in high-density orchards, is a pressing issue. This problem has been associated with abiotic (flood, drought, freeze) and biotic stressors (fungi, bacteria, and insects). Ambrosia beetles (AB) (Xylosandrus spp.) have been linked to stressed trees suffering from RAD. However, the direct association is still not clear. We evaluated the effects and interactions of rootstock (‘B. 9’, ‘M. 7’, and ‘G. 41’) and water stress (flood, drought, control) on physiological responses and AB colonization. Specifically, a greenhouse experiment was performed in spring 2023 on 14-month-old potted ‘MAIA1’ trees. Trees were subjected to water stress for 20 d. Water stress treatments consisted of a saturated pot-in-pot system for flood, water with-held for the duration of the experiment for drought, and irrigation based on soil moisture, maintaining the pots between 0.7 and 1 water fraction volume for control trees. The experiment had a randomized complete block design, was replicated 10 times, and had a factorial treatment structure. Measurements were made every 2 d for soil moisture, fluorometry, and spectrometry data, every 4 d for leaf gas exchange and midday water potential, at 7 and 14 d for ethanol volatiles, and at the termination of the experiment for AB colonization. Under control conditions, ‘G. 41’ trees had higher transpiration, stomatal conductance, and assimilation rates than ‘B. 9’ and ‘M.7’ trees. However, after 4 d of stress, ‘G. 41’ showed a more rapid decline in leaf gas exchange parameters relative to other rootstocks. Drought-stress trees from the three rootstocks declined 4 d faster than flood trees during the first 12 d. However, this decline occurs more abruptly in ‘G. 41’ and ‘M. 7’ trees. From 16 to 20 d, drought and flooded trees have a similar response. Under control conditions, all three rootstocks have similar quantum efficiency values. Conversely, under water stress, ‘G. 41’ and ‘M. 7’ declined faster than ‘B. 9’ trees, with a more severe response to drought for ‘G. 41’ and ‘M. 7’ trees. Chlorophyll index (Ci) showed lower values for flood and drought trees after 10 d for ‘G. 41’ and ‘M. 7’ trees. For ‘B. 9’, this was only true in drought trees. Flooded trees had AB tunnels three times longer than control, and drought trees were the only ones where AB larvae were observed, which was linked to higher ethanol levels.
Speakers
MM

Melissa Munoz

NC State University
Co-authors
CR

Christopher Ranger

USDA-Agricultural Research Service
NA
TM

Thomas M. Kon

NC State University
NA
Thursday September 26, 2024 11:15am - 11:30am HST
South Pacific 2

11:15am HST

WCPM 3 - Effect of Application History on Preemergence Herbicide Persistence
Thursday September 26, 2024 11:15am - 11:30am HST
Preemergent herbicides are commonly applied to control many annual weed species in turfgrass systems. Oxadiazon and prodiamine are pre-emergent herbicides that effectively inhibit the growth of emerging annual grasses and broadleaf weeds without harming certain turfgrass species. However, in recent years, a decline in the efficacy of oxadiazon and prodiamine has been observed by golf course managers, leading to an increase in application rates in an attempt to mitigate the issue. Therefore, the objective of this study was to characterize degradation processes that affect oxadiazon and prodiamine persistence and efficacy in order to identify solutions or mitigation strategies. Soil samples were collected from unique sites throughout North Carolina. Field studies were organized as a randomized complete block design containing 3 replications and 2 experimental runs. Treatments were arranged in a split-split plot design, where the whole plots consisted of 4 sites with histories of continuous oxadiazon or prodiamine use (never applied, applied 1-2 years, ~7 years, > 15 years), the sub-plots were 2 treatments (non-sterilized and sterilized), and the sub-sub-plots were 6 collection timings (14, 28, 42, 56, 112, and 168 days after treatment). Herbicide residue quantifications were determined using high-performance liquid chromatography. Data were recorded and converted into a percentage of the applied rate. A higher percent of oxadiazon was observed for sterilized soil (79.2%) compared to non-sterilized soil (73.7%). In the non-sterilized soil, at 14 DAT there were no differences between periods of use. However, at 28 DAT, the soil with no use history presented a higher percentage of oxadiazon (83.0%) compared to 1 and 15 years (75.5%, and 77.1% respectively). Furthermore, at 42 and 56 DAT, the soil with no history of application exhibited the highest percentage of oxadiazon among all periods of use. Findings of this study suggest that there is higher concentration of oxadiazon, meaning less degradation, in the soils with no history of application.
Speakers
TG

Travis Gannon

NC State University
Co-authors
AV

Alex Veverka

NC State University
NA
EG

Estefania Gomiero Polli

NC State University
NA
KA

Khalied Ahmed

NC State University
NA
RR

Ronald Rogers

NC State University
NA
Thursday September 26, 2024 11:15am - 11:30am HST
Lehua Suite

11:20am HST

Syngenta Recruiter Talk
Thursday September 26, 2024 11:20am - 11:50am HST
Speakers
Thursday September 26, 2024 11:20am - 11:50am HST
Coral 5

11:29am HST

Consumer Horticulture and Master Gardeners/Human Issues in Horticulture/Public Horticulture (CHMG/HIH/PUBHORT)
Thursday September 26, 2024 11:29am - 12:50pm HST
Curated Literature as Continuing Education for Master Gardener Volunteers - Alicia Herzog
A Landscape Performance Evaluation of Sun-Loving Impatiens x hybrida in Mississippi - Scott Langlois
Evaluation of Selected Commercially Available Tabletop Hydroponic Systems and Their Performance on Lettuce (Lactuca sativa) Growth Characteristics - Leonard Githinji
Needs Assessment Evaluation to Inform Statewide Horticulture Newsletter - Cynthia Domenghini
Master Gardener Volunteers Learn Basic Plant Research Through the A.R.T.S. Rose Evaluation Program - Jeff Wilson
Moderator
CD

Cynthia Domenghini

Kansas State University
Thursday September 26, 2024 11:29am - 12:50pm HST
Kahili

11:29am HST

Vegetable Crops Management 3 (VCM 3)
Thursday September 26, 2024 11:29am - 1:40pm HST
Evaluating Faba Bean (Vicia faba) Performance Using Desalinated Irrigation Water and Compost Amendments in the Southwest - Jannatul Afroze
Investigating Microclimate Conditions and Vegetable Yield under Agrivoltaics Systems in Grafton, MA”. - Mamata Bashyal
Planning for Success: A Roadmap to Establishing a Certified Naturally Grown Production Plot - Shelby Mendoza
Fertility Management in Soilless Growth Media for Beet Crop Production. - Bryce Waugh
Adaptation of AgRobotics for Onion Production in High Organic Matter Soils - Mary Ruth McDonald
Effect of Mineral Nitrogen and Foliar Spraying of Humic Acid on Fresh and Dry Leaves and Roots Weights, and Root Length - Ali Omar
Dual-cropping Sweetpotato for Greens and Root Production - Laura Schulz
Effect Of Selenium Fertilization on Beta-carotene Accumulation in Hydroponically Grown Two cress Varieties - Adekunle Adeyeye
Effect Of Levels Of Magnesium Fertilization On The Carotenoid Accumulation Among Three Kale Cultivars Grown Hydroponically. - Alex Kofi
Red And Blue LED Lighting Effects On Hydroponically Grown 'Koba' Green Onion - Kent D. Kobayashi
Plant Health Aerial Mapping Integration In Precision Agriculture Systems - Wael Elwakil
Evaluation of Vegetable Soybean Adaptations to South Florida’s Tropical Climate - Xiaoying Li
Lettuce Cultivar Trials in a Deep-Water Culture (DWC) Hydroponic System - Alireza Rahemi
Moderator
LS

Laura Schulz

Washington State University
Thursday September 26, 2024 11:29am - 1:40pm HST
South Pacific 4

11:30am HST

CHMG/HIH/PUBHORT - Curated Literature as Continuing Education for Master Gardener Volunteers
Thursday September 26, 2024 11:30am - 11:40am HST
There has long been demand from the Master Gardener population for approved continuing education credit for reading specific literature. This program aims to fill that gap while defining a clear scope of acceptable reading material and demonstrable learning. A quarterly suite of reading materials was made available to program participants through email. Participants have one quarter (3 months) to read the materials and complete a quiz through Qualtrics. Participants who successfully completed the quarter were awarded one hour of continuing education toward their annually required minimum. Results from the first quarter of the study indicate positive change in knowledge across all areas surveyed from pre- to post-. For the first topic, tree care and planting, participants were asked to rank their knowledge about proper planting techniques, factors affecting decline in trees, selecting appropriate planting sites, identifying tree problems, and managing storm damage to trees. In all areas, at least a few participants reported not being knowledgeable at all prior to completing the educational materials. When asked about their knowledge after completing the materials, no participants reported this level of lack of knowledge. The greatest improvements were seen in the areas of knowledge about identifying tree problems and managing storm damage to trees. When asked about knowledge of managing storm damage to trees prior to completing the educational materials, 43.6% reported being not at all knowledgeable, 30.8% reported being slightly knowledgeable, 23.1% reported being moderately knowledgeable, and 2.6% reported being very knowledgeable. After completing the materials, 12.8% reported being slightly knowledgeable, 48.7% reported being moderately knowledgeable, 33.3% reported being very knowledgeable, and 5.1% reported being extremely knowledgeable. The assessment also included open-ended questions that asked participants to envision how they would put the knowledge to use in their volunteer roles. More research is needed to determine if knowledge gained from literature review is both worthwhile and feasible for volunteer development and continuing education. The study is being conducted over the course of a year, with participants able to opt out of any quarter they do not feel inclined to participate in. First quarter results show high participation and high knowledge gain, but more information is needed to see if engagement and knowledge gain remain high after the initial novelty period has worn off.
Speakers
avatar for Alicia Herzog

Alicia Herzog

Iowa Master Gardener Program Coordinator, Iowa State University
Thursday September 26, 2024 11:30am - 11:40am HST
Kahili

11:30am HST

VCM 3 - Evaluating Faba Bean (Vicia faba) Performance Using Desalinated Irrigation Water and Compost Amendments in the Southwest
Thursday September 26, 2024 11:30am - 11:40am HST
Water and soil salinity pose a significant challenge to global food production, particularly in semi-arid and arid regions. In many of these areas, the only available irrigation water often has high salinity levels. Utilizing irrigation water with high salinity can lead to salt accumulation in the rhizosphere, causing reduced infiltration rates, yield losses, decreased crop quality, and even potential plant mortality. Two strategies to address water and soil salinity include integrating compost soil amendments and implementing water desalination techniques. In addition to these two strategies, legumes are suitable crops for enhancing bioproductivity and reclaiming marginal lands due to their symbiotic association with rhizobia bacteria that can increase soil nitrogen. The objective of this study was to evaluate how the combined use of saline and desalinated water for irrigation, along with compost amendments, impacts faba bean germination, growth, physiology, and nodulation. Two common faba bean cultivars, Broad Windsor and Aquadulce were planted in fall of 2023 in field plots at the arid Brackish Groundwater National Desalination Facility, Alamogordo, NM, USA. Faba bean cultivars were grown in a combination of treatments of mulched composted wood with soil, bare soil, saline (1.97 dS/m) irrigation water, and desalinated (0.80 dS/m) irrigation water. Germination rates, plant nutrient composition, chlorophyll index, nodulation weight and number, along with root weight were measured. Preliminary results show that compost treatment as a main effect had a significant effect on faba bean germination rates with a 22-26% reduction in germination at 18, 25, and 35 days after planting (DAP) in plots with compost. By 107 days after planting, faba bean plants in the compost-treated plots showed no signs of nodulation, whereas the majority of plots without compost had nodules present. Water treatment significantly influenced the chlorophyll index of faba beans at 107 DAP; plants irrigated with saline water exhibited higher chlorophyll indexes. Compost treatments could have influenced germination rates due to variations in soil temperature, while nodulation might have been affected by adequate nitrogen potentially supplied by the compost. Upon completion of the current season and subsequent second season, we will have a more comprehensive basis to evaluate the relationships between compost application, saline irrigation water treatments, and their impacts on faba bean growth.
Speakers
JA

Jannatul Afroze

New Mexico State University
Co-authors
BS

Breana Smithers

University of North Texas
NA
IJ

Israel Joukhadar

New Mexico State University
MA

Miguel Acevedo

University of North Texas
NA
SW

Stephanie Walker

New Mexico state University
NA
Thursday September 26, 2024 11:30am - 11:40am HST
South Pacific 4

11:30am HST

CE 5 - Adjusting Supplemental LED Light Intensities Based on Real-time Chlorophyll Fluorescence Measurements in a Greenhouse
Thursday September 26, 2024 11:30am - 11:45am HST
Precise and efficient control of supplemental lighting is vital to minimize electrical energy costs in controlled environment agriculture. Even though various environmental factors such as temperature, vapor pressure deficit, CO2 concentrations, and water status influence photosynthetic capacity, current supplemental light control strategies are controlled only based on ambient sunlight conditions. Meanwhile, chlorophyll fluorescence is widely used as an indicator of environmental stress and photosynthetic capacity on account of its easy and non-invasive measurement. A chlorophyll fluorescence-based biofeedback system has been proposed as an innovative approach for precise control of supplemental LED light intensities. The biofeedback system can dynamically optimize LED light intensities based on real-time measurements of chlorophyll fluorescence while allowing plants to decide the amount of supplemental light they need. The biofeedback system has been previously validated in a growth chamber, but its application in an actual greenhouse condition remains unexplored. The objective of this research was to implement the biofeedback system in a greenhouse environment for real-time control of supplemental light intensities based on photosynthetic activity. Additionally, the productivity and energy efficiency of the biofeedback strategy were evaluated and compared to conventional light control strategies. Two fluorometers (MINI-PAM; Heinz Walz, Effeltrich, Germany) were used to monitor the electron transport rate (ETR) and quantum yield of photosystem II (ΦPSII) every 10 minutes, and the Biofeedback system adjusted supplemental LED light intensities until the predefined target ETR and ΦPSII were achieved. Three popular greenhouse crops [lettuce (Lactuca sativa), sweet basil (Ocimum basilicum), and spinach (Spinacia oleracea L.)] were grown under five supplemental light conditions. Specific targets of 1) electron transport rate (ETR), 2) quantum yield of photosystem II (ΦPSII), 3) photosynthetic photon flux density (PPFD), 4) daily light integral (DLI), and 5) no control (ambient sunlight) were used to control supplemental light intensities. In contrast to conventional lighting control methods, the biofeedback system tailored supplemental light intensities according to not only sunlight levels but also temperature and humidity. The result underlines the effectiveness and energy efficiency of the biofeedback system that could integrate variable environmental factors in the greenhouse and apply them to adjust supplemental light intensities precisely.
Speakers
SN

Suyun Nam

University of Georgia
Co-authors
LB

Leonardo Bastos

University of Georgia
NA
MH

Mark Haidekker

University of Georgia
NA
MY

Melanie Yelton

Grow Big CEA Consultants
NA
RF

Rhuanito Ferrarezi

University of Georgia
NA
SN

Savithri Nambeesan

University of Georgia
NA
Thursday September 26, 2024 11:30am - 11:45am HST
South Pacific 3

11:30am HST

FRBR 1 - A Deep Learning‐based Smartphone App for Blueberry Yield Prediction
Thursday September 26, 2024 11:30am - 11:45am HST
The global blueberry market has been expanding vastly driven by consumer demand for healthier food. As a top blueberry producer, United States generated a revenue of $932 million in 2020. A profitable blueberry industry relies on continued cultivar improvement. One challenge faced by blueberry breeders, researchers, and growers, is yield data collection. Measuring blueberry yield by manual sampling is labor-intensive and time-consuming. We developed a smartphone application leveraging deep learning techniques to automate yield prediction and maturity assessment for different blueberry cultivars under field conditions. State of the art YOLOv8 models were fine-tuned and evaluated using a dataset of side-view images of various southern highbush and rabbiteye blueberry cultivars. The best performing DL model of YOLOv8-x achieved a mean average precision of 0.708 and 0.372 under 0.5 and 0.5-0.95 Intersection over Union thresholds on validation datasets, respectively. Blueberry yield was predicted using non-linear regression-based machine learning models using the image-derived mature berry count multiplied by user-defined average berry weight and cultivar as explanatory variables with satisfactory accuracy. This proposed smartphone app can enable image-based yield prediction for blueberry growers and breeders, which is valuable for management decision making and accelerated selection for high-yielding cultivars.
Speakers
SR

Sushan Ru

Auburn University
Co-authors
PS

Puranjit Singh

University of Delaware
NA
YB

Yin Bao

University of Delaware
NA
Thursday September 26, 2024 11:30am - 11:45am HST
South Pacific 1

11:30am HST

PB 3 - Declining Phosphorus Availability Increases Sucrose Synthase Activity and Storage Root Formation in Sweetpotato cv Beauregard Adventitious Roots
Thursday September 26, 2024 11:30am - 11:45am HST
Sucrose Synthase (SuSy) plays a crucial role in sugar metabolism mainly in the sink tissues of plants. In sweetpotato, increased SuSy activity has been associated with increased storage root development and correlated with sink strength. However, little is known about the specific variables associated with increased SuSy activity. Evidence from model systems supports the hypothesis that phosphorus (P) starvation is associated with increased accumulation of carbohydrates in roots. In the first study, we measured SuSy gene expression in ‘Beauregard’ sweetpotato grown in a split root system and subjected to the following P treatments: positive control ( / ), negative control (0/0), declining P (-/-), and split P ( /-). The declining P treatment corresponded to 25, 50, 75 and 0% progressive reduction in P and was imposed on days 6, 9, 12, and 15, respectively. A second study was conducted to measure storage root development at 50 days. The (-/-) treatment was associated with increased SuSy activity in developing adventitious starting at 11 days after planting. Moreover, plants grown with the declining P treatment produced storage roots with larger diameter (>2cm) significantly higher than the positive control. Decreased SuSy activity was associated with reduction in storage root number among P-deficient (0/0) plants. Taken together, these results support the hypothesis that P availability in the root zone is associated with sink strength and storage root formation signaling in adventitious roots. These findings can be used to develop tools and management practices to increase P fertilizer efficiency for consistent storage root yields in sweetpotato.
Speakers
MB

Marissa Barbosa

Lousiana State University
Co-authors
AV

Arthur Villordon

LSU Agcenter
CG

Cole Gregorie

LSU AgCenter Sweetpotato Research Center
NA
DL

Don La Bonte

Louisiana State Univ
NA
LA

Lisa Arce

Louisiana State University
MA

Mae Ann Bravo

Louisiana State University
Thursday September 26, 2024 11:30am - 11:45am HST
Nautilus 1

11:30am HST

POM 3 - The Role of Photosynthesis in the Regulation of Early Fruit Growth of Apple
Thursday September 26, 2024 11:30am - 11:45am HST
Photosynthesis is well-known to not only occur in leaves but also other tissues like stems, sepals, and fruits. Fruit photosynthesis has been documented in cucumber, tomatoes, satsuma mandarins, prickly pear, wheat, and apple. Fruit photosynthesis occurs in these instances not only to contribute to carbon assimilation but to support other metabolic processes, the synthesis of metabolites, and seed development. Early fruit growth in apple is regulated by energy-intensive cell division that lasts for approximately five weeks before switching to a phase of predominantly cell expansion-driven growth. Thus, fruit photosynthesis during early fruit development in apple could function to fulfill the resource and energy requirements necessary for the growth and development of fruit tissues. To examine this potential contribution of photosynthesis to apple fruit metabolism, shade bags made of 30%, 65%, and 80% shade cloth were placed on fruitlets at 16 days after full bloom. The effects of fruit shading on fruit tissue plastid ultrastructure, metabolite composition and tissue transcriptomes were analyzed. Using transmission electron microscopy (TEM), we found that plastids in the peel and cortex overall resembled that of photosynthetically active plastids; they contained stromal and granal thylakoids similar to those found in leaves. Spatially, pith plastids displayed unique hypergranal features , with increased granal thylakoids and a significantly reduced presence of stromal thylakoids. When compared to the control, 80% shaded peel plastids contained more plastoglobuli, and 80% shaded pith plastids displayed prolamellar bodies, which are indicative of disassembly. Further, significantly lower chlorophyll a concentration was observed in shaded fruit. Metabolite analyses indicated that sorbitol was significantly greater in shaded fruit than in the control. Transcriptome analyses indicated substantial changes associated with carbohydrate metabolism in the fruit cortex and peel in response to fruit shading. Together, these analyses indicate a significant contribution of fruit photosynthesis to early fruit growth and development in apple.
Speakers
BR

Bayleigh Roussel

University of Georgia
Thursday September 26, 2024 11:30am - 11:45am HST
South Pacific 2

11:40am HST

CHMG/HIH/PUBHORT - A Landscape Performance Evaluation of Sun-Loving Impatiens x hybrida in Mississippi
Thursday September 26, 2024 11:40am - 11:50am HST
A long-standing favorite for shade gardens, Impatiens remain a popular choice for home gardeners who crave the multi-colored bloom options and long season performance. Many varietal choices currently exist for incorporation of these garden favorites into sunny locations. Full sun coupled with high heat and humidity of the deep South can add layers of challenges when growing Impatiens. A variety trial of sixteen cultivars of ‘sun safe’ Impatiens was conducted in Mississippi USDA hardiness zones 8b and 9a. Selected varieties of the SunPatiens® and Solarscape® series were procured as unrooted cuttings in the Spring of 2023 and after rooting and growing out in 3.25” pots, they were planted in the landscape as four 2-plant reps in full sun at two locations. These trials were conducted at the Mississippi State University South Miss Branch Experiment Station in Poplarville, MS and at the MSU Truck Crops Experiment Station in Crystal Springs, MS. Evaluations of flowering quality, plant health and overall landscape performance were made every two weeks on a 1-5 rating scale (5 = top rating). Irrigation was provided via drip tape daily. The summer of 2023 saw some of the driest and hottest weather observed in recent years at these locations with many days recorded over 100 degrees F. Results from the two trial sites showed the same two cultivars with the highest average numerical rating: SunPatiens® Classic White and Blush Pink (results not significant). This variety trial is expected to be expanded to include additional cultivars and locations in 2025.
Speakers
SL

Scott Langlois

Miss State University
Co-authors
SB

Shaun Broderick

Mississippi State University
TK

Tricia Knight

Mississippi State University
NA
Thursday September 26, 2024 11:40am - 11:50am HST
Kahili

11:40am HST

VCM 3 - Investigating Microclimate Conditions and Vegetable Yield under Agrivoltaics Systems in Grafton, MA”.
Thursday September 26, 2024 11:40am - 11:50am HST
Agrivoltaics is the simultaneous production of both solar energy and crops on the same land. The success of crops grown underneath the panels depends on the crop type, soil composition, regional climate conditions, and panel configuration (height, row spacing, tilt angle, and tracking system). There is a need for more research-based guidance on the trade-offs between energy and crop production in agrivoltaics systems. The objective of this study was to compare the microclimate conditions and crop performance within a solar array to the control (without a solar array). The on-farm agrivoltaics study was conducted from July to September 2023 in Grafton, MA, using two contrasting crops: butternut squash (sun-loving) and Boston lettuce (shade tolerant). Microclimate variables such as photosynthetically active radiation (PAR), air temperatures, soil temperatures, soil moisture, and relative humidity were monitored at different transect positions within the solar array [BP 1 (under leading panels), BP 2 and BP 3 (between two panels), and BP 4 (under the back panel)] and control. Data were analyzed in R statistical software using an independent sample t-test to compare control to array and test and one-way ANOVA to compare each bed position within the array only. Preliminary findings showed higher mean and maximum PAR in control than in BP 1, BP 2, and BP 4 within the array. Air temperature (mean and maximum) was found to be higher in control than in the array. Mean and maximum soil temperature was highest in control when compared to BP 1 and BP 2 under the array. Similarly, mean relative humidity was found to be significantly higher in the control than in the array. The chlorophyll index of butternut squash showed a positive correlation with decreasing PAR, suggesting potential adaptive responses to varying light conditions. Butternut squash fruit yield was similar across the four different bed positions under the array, and lettuce yield under the array was similar to that of the control area. Further continuation of this study in 2024 provides insights for growers about the successful production of butternut squash and lettuce production under the agrivoltaics system.
Speakers
MB

Mamata Bashyal

University of Massachussets
Co-authors
CC

Clem Clay

University of Massachusetts
NA
SC

Sam-Glaze Corcoran

University of Massachusetts, Amherst
NA
Thursday September 26, 2024 11:40am - 11:50am HST
South Pacific 4

11:44am HST

Undergraduate Student Poster 2 (UG 2)
Thursday September 26, 2024 11:44am - 1:25pm HST
Perceptions of Gardens and Gardeners - Belinda Brain
Horticultural Activities Impact the Perceived Stress Levels of Undergraduate Students - Baylie Weld Latter
Perceptions of Media Literacy in Undergraduate Students and Master Gardeners - Caleb Spry
Identifying the Role of the Chloroplast-Mediated CEBP Transcription Factor in Petunia Flower Senescence - Colin Krisulevicz
Optimal production densities and storage conditions for five microgreens - Sam Petrovich
Irrigation Level Affects Bloom Number and Pollinator Visits in Herbaceous Perennials - Madison Coyle
Strawberry Response to Compost Versus Inorganic Nitrogen - Kauai Paule
SOFT Science: Cultivating Sustainable Horticulture Leaders Through the Student Organic Farm Training Program - Alana Marie Barros
Phenological Modeling of Pollenizing Crabapple Cultivars (Malus spp.) and Commercial Apple Cultivars (Malus X domestica - Miranda Woodcock
Determining Sap Yield, Sugar Content, and Mineral Composition of European White Birch Trees - Abby Porter

Thursday September 26, 2024 11:44am - 1:25pm HST
Coral 1

11:45am HST

UG 2 - Perceptions of Gardens and Gardeners
Thursday September 26, 2024 11:45am - 11:55am HST
Studies have been conducted on the preferences and opinions of individuals for garden and landscape spaces with varying amounts of plants (Zheng et al., 2011). However, little data exists on the perceptions individuals hold about the gardeners that grow these garden spaces. An online survey was created containing images that represent three outdoor spaces with three different amounts of plant material and complexity. The images with different amounts of plant material were created with artificial intelligence assisted software to modify the identical base backgrounds. Participants were asked a variety of questions about each space, then about the “gardener” who created the space. The survey contained twenty short answer questions and eighteen sliding scale questions to provide a diverse data set. Participants in the survey were undergraduate students in an introductory horticulture class, high school students in agriculture education classes, and adults training to be Master Gardeners. Data from undergraduate students reveals there was a positive correlation between the amounts of plant material and the respondent’s opinions on the gardener’s level of education, age, socioeconomic status, and gardening experience. Less plant material corresponded to a perception of lower levels of education, age, status, and experience. Thus, respondents consider areas with the highest amount of plant material to be created by more highly educated, older individuals with higher socioeconomic status and more gardening experience. These results allow us to better understand the public’s perception of gardens and gardeners, assisting us in creating more applicable materials for classes and facilitating more productive interactions with the public.
Speakers
BB

Belinda Brain

Iowa State University
NA
Thursday September 26, 2024 11:45am - 11:55am HST
Coral 1

11:45am HST

CE 5 - Interactions of Far-Red Photons with Orange Photons or Red Photons: Photosynthetic Response, Morphology and Fruit Yield
Thursday September 26, 2024 11:45am - 12:00pm HST
Plant response from the interaction between far-red and orange photons were rarely known, compared to that of far-red and red photons. Recent previous studies have found application of supplemental orange photons increases the openness of tomato plant architecture, resulting in improved dry weight than supplemental blue, green and red photons. However, limited information is available on the effects of orange photons on plant growth, morphology, and photosynthetic efficiency. Thus, our objective was to quantify the effects of orange photons on growth and photosynthetic responses during long term crop cultivation, compared to red photons. Dwarf tomatoes ‘Red Robin’ were grown in a walk-in chamber with controlled environmental conditions for 96 days after sowing (day temp. 24.3 ± 0.4℃ / night temp. 19.8 ± 0.5℃ and RH 60.5 ± 3.5%). Four light spectral treatments were applied as follows: 1) B25G25O200 (orange), 2) B25G25R200 (red), 3) B25G25O165FR35 (O FR), and 4) B25G25R165FR35 (R FR) (subscripts denote photon flux densities in µmol m² s-1). All spectral treatments had the same total light intensity of 250 µmol m² s-1 with a 18-h photoperiod. Leaf photosynthetic rate was measured before the fruit stage under sole-source orange or red light, as well as under combination lights (RGB or OGB), in a random order. Plant height and main stem length significantly increased under the two spectral treatments with far-red photons (i.e., O FR or R FR), compared to treatments without far-red photons (i.e., orange and red treatments). In comparison between orange and red treatments (without far-red), total dry weight of orange treatment was significantly higher than in red. However, the trend was opposite in the treatments with far-red photons (O FR treatment was lower than R FR treatment). In comparison between with and without far-red photons, total leaf area and fruit dry weight under far-red photons were significantly higher than those in the treatments without far-red photons, whereas stem weight was lower. Brix° under with far-red photons was higher than the treatment without far-red, and that of orange treatment was higher than in the red. Photosynthesis rate under sole-source orange photons was higher than under red photons, but no significant difference was observed among under combination lights. Overall, our results indicated that application of orange photons instead of red photons led to improved biomass and fruit yields in dwarf tomato, resulting in enhanced openness in the canopy structure; however, the trends were reversed with the application of far-red photons.
Speakers Co-authors
SZ

Shuyang Zhen

Texas A
NA
Thursday September 26, 2024 11:45am - 12:00pm HST
South Pacific 3

11:45am HST

FRBR 1 - Utilizing Optical Sorting Technology for High-Throughput Phenotyping in Sweet Cherry Breeding
Thursday September 26, 2024 11:45am - 12:00pm HST
Phenotyping remains a bottleneck in many breeding programs, including sweet cherry. Current fruit evaluation protocols require extensive manual sorting and visual evaluation, which reduces throughput and is subject to evaluator bias and fatigue. The Washington State University Cherry Breeding Program is seeking more efficient methods of evaluating fruit quality. In 2023, the program acquired an optical fruit sorter. Our objective was to customize the sorter parameters according to breeding program needs and compare the results of the sorter with traditional methods. Our Tomra InVision 2 sorter has the same optics, software and computer hardware as a commercial sorter, but operates on a single lane. Fruit are loaded onto an infeed system which passes fruit in single file into the detection area. A combination of fruit rotation, multiple cameras and mirrors is designed to image the entire surface of individual fruit. Both visual and infrared images are captured, generally > 24 images per fruit at a rate of approximately 15 fruit per second. The sorter software identifies fruit and classifies them according to a set of tunable quality parameters or grades. Air-actuated valves then eject the fruit into one of four grade-determined exits. The sorter generates reports that include the fruit size profile as well as the percentage of fruit sorted into the various exits and/or grades. The sorter shipped with a pre-loaded map (sorting algorithm), which we modified by updating with data from representative images of various quality parameters. We then used the sorter to grade fruit from Phase 2 variety trials. We analyzed 50-fruit subsamples in the traditional manner for size and defects. All remaining fruit from each sample were analyzed via the sorter. Out of 20 samples evaluated, the average number of fruit per sample evaluated by the sorter was 154, vs. 50 for manual evaluation. Overall, the sorter detected a lower percentage of cracking, doubles (polycarpy), and pitting vs. manual evaluation, and a higher percentage of skin blemishes. Continued testing will be required to determine whether these differences are due to the effects of small sample size or bias due to the methods themselves (human evaluator vs. sorter). While the sorter required a similar number of personnel as for manual evaluation, it required less time to evaluate each sample even though more fruit were analyzed. We will expanding the use and testing of the sorter in 2024, including evaluation of postharvest quality.
Speakers
PM

Per McCord

WASHINGTON STATE UNIVERSITY
Co-authors
MM

Marcella Magby

Washington State University
NA
Thursday September 26, 2024 11:45am - 12:00pm HST
South Pacific 1

11:50am HST

CHMG/HIH/PUBHORT - Evaluation of Selected Commercially Available Tabletop Hydroponic Systems and Their Performance on Lettuce (Lactuca sativa) Growth Characteristics
Thursday September 26, 2024 11:50am - 12:00pm HST
With increasing urban populations and limited arable land for horticultural production, food security is becoming a growing concern worldwide. Hydroponic systems, defined as cultivation techniques involving soilless media, offers a potential solution to enhance food security by increasing urban food production. For this study three tabletop hydroponic systems, viz., iDOO, INT, and MUFGA were used for cultivating of Rex butterhead lettuce (Lactuca sativa). Three seeding trays, with 200 cells each embedded with rockwool were sowed 9 days before being transplanted into the hydroponic units. Growth parameters were recoded for 6 weeks, viz., plant height, and leaf number, length, and width. Visual rating (1 through 10) were also recorded. Additionally, the pH and the electrical conductivity (EC) of the nutrient solution were monitored. Following the harvest, fresh weight and root length were recorded. The data collected was subjected to ANOVA. Results indicated that plants grown in MUFGA unit were significantly (p
Speakers
LG

Leonard Githinji

Virginia State University
Co-authors
JK

Julia Kabbani

Virginia State University
NA
Thursday September 26, 2024 11:50am - 12:00pm HST
Kahili

11:50am HST

VCM 3 - Planning for Success: A Roadmap to Establishing a Certified Naturally Grown Production Plot
Thursday September 26, 2024 11:50am - 12:05pm HST
In the face of escalating environmental concerns, the horticultural sector is encouraged to pivot towards more sustainable and environmentally friendly production practices. Specifically, Certified Naturally Grown (CNG) emerged in 2002 as a new production system for small-scale producers rooted in organic farming principles and relying on peer-reviewed certification that fosters a community network. However, there is limited literature on the process of achieving CNG certification. Hence, this research strives to provide a detailed roadmap of the different phases of setting up a demonstrational CNG production system at the Oklahoma State University Student Farm including strategic planning and execution phases. The research plot is intended to serve as both an educational tool and a practical guide for growers aiming to transition to CNG practices. The implementation of this project began with familiarizing ourselves with the CNG organization, their inspection processes and planning accordingly. This is crucial to ensure the plot meets CNG criteria, focusing on sustainable practices and ecological balance from the outset. Next, the planning phase encompassed establishing the research plot including site selection, soil analysis, anticipated barriers of CNG certification, plot design and layout, resource assessment, and an implementation timeline. The planning phase aids in physically establishing the CNG demonstration plot and ensuring its role as a research and educational hub. By accurately addressing each planning component, the project aims to lay a solid foundation to demonstrate the viability of CNG practices in Oklahoma, stimulate community engagement, and promote a deeper understanding of sustainable agriculture practices. Ultimately, this project seeks to illustrate the detailed strategic planning and preparation required to develop a CNG production system. The education tools we develop will provide a template for producers aiming for CNG certification. With this initiative, we aim to educate growers on sustainable and resilient production methods and enable a transition towards them.
Speakers
SM

Shelby Mendoza

Oklahoma State University
Thursday September 26, 2024 11:50am - 12:05pm HST
South Pacific 4

11:50am HST

Louisiana State University Agricultural Center
Thursday September 26, 2024 11:50am - 12:20pm HST
Speakers
DP

David Picha

Louisiana State University Agricultural Center
Thursday September 26, 2024 11:50am - 12:20pm HST
Coral 5

11:55am HST

UG 2 - Horticultural Activities Impact the Perceived Stress Levels of Undergraduate Students
Thursday September 26, 2024 11:55am - 12:05pm HST
After the COVID-19 pandemic, the topic of gardening activities and their impact on stress gained much attention. Undergraduate students often complain of being overwhelmed or stressed, and gardening activities have been shown to reduce stress for some people (Makayla et al., 2023). Therefore, as instructors, we thought it would be interesting to see if undergraduate students realize a benefit from hands-on, horticulture labs. The purpose of this study was to determine if hands-on horticulture activities reduced stress in undergraduate students in a horticulture class at Iowa State University. We investigated the perceived stress of undergraduate students before and after lab activities for Home Horticulture (Hort 121) course. We used a modified ten-question Perceived Stress Scale (PSS) to measure and assess students’ stress levels (Cohen, 1983). Four labs (out of 14) were selected for this study. Each lab lasted 50 minutes and included a hands-on, experiential activity. Three lab sections with approximately 25 students in each section, participated in this study. Two of the labs were administered outdoors and two were administered indoors. Students completed the modified PSS immediately before and after these lab activities. Data were compiled and analyzed in Excel. Preliminary results indicated moderate improvement in stress levels by students in all lab sections. In addition, almost all students enjoyed these lab activities. Future data analysis will determine if there are differences in stress reduction between indoor or outdoor lab activities. The results from this study can give undergraduate students alternative stress management practices to help them thrive in stressful times. Practical and effective stress management skills are important for their academic performance and general well-being.
Speakers
BW

Baylie Weld Latter

Iowa State University
NA
Thursday September 26, 2024 11:55am - 12:05pm HST
Coral 1

11:59am HST

Temperate Tree Nut Crops 2 (NUTS 2)
Thursday September 26, 2024 11:59am - 1:30pm HST
A Look at Heat Stress on Micro-propagated Pecan Trees - Doris Alexa Arnedo
Unraveling the role of LEA(Late embryogenesis abundant) genes in pecan stress resilience - Sahithi Pulicherla
Discovery of Early Biomarkers for the Scab Resistance of Pecan Seedlings Using Metabolomic Analysis Combined with Machine Learning Algorithms - Min Jeong Kang
Developmental Transcriptomics of Pecan Fruit in ‘Mahan’ and ‘Tiny Tim’ - June Labbancz
Pistachio Orchard Productivity Enhancement Through Molecular Marker Preselection - Ewelina Jacygrad
Fatal Flaws of Experimental Almond Varieties and Selections - Luke Milliron
Advancing Cocoa Yield Forecasting in Ecuador Using Machine Learning and Field Data Integration - Daniel Mancero
Maturity stage at harvest modulates fruit softening and quality of jackfruit - Zora Singh
Growing papaya in Mississippi - Guihong Bi


Moderator
avatar for Doris Alexa Arnedo

Doris Alexa Arnedo

New Mexico State University
Thursday September 26, 2024 11:59am - 1:30pm HST
Lehua Suite

11:59am HST

Weed Control and Pest Management 2 (WCPM 2)
Thursday September 26, 2024 11:59am - 1:40pm HST
Evaluating Bacterial Diversity and Pest Control Efficacy of Steam Disinfestation Treatments in the Salinas Valley Spinach and Lettuce Fields - Erika Escalona
Development of Minirhizotron for Nondestructive Rapid Detection of Parasitic Nematodes - Tim Pannkuk
Genome Sequencing of Crapemyrtle Bark Scale for Developing Advanced IPM Strategies - Bin Wu
A New Technique for Visual and Quantitative Assessment of Pesticide Applications to Tree Trunks for Control of Trunk-boring Insects - Amy Fulcher
Factors Affecting Spray Coverage on Red Maple Trunks from an Air-Assisted Sprayer - Amy Fulcher
Rice Hull Use in Container Production; Economics and Efficacy - Shawn Steed
Organic and Synthetic Herbicides for Controlling Liverwort Growth in Containerized Ornamental Production - Manjot Sidhu
Impact of Changing Climate on Weed Control in Ornamental Crop Production: A Potential Research Area - Supti Saha Mou
Development of “EZA”, a New Pesticide Suitable for Organic Production of Horticultural Crops - Merci Uwimbabazi
Impact of Partial Saltwater Agroecosystems on Weed Competition in Watermelon. - Joseph Bazzle
Moderator
SS

Shawn Steed

University of Florida
Thursday September 26, 2024 11:59am - 1:40pm HST
South Pacific 2

12:00pm HST

CHMG/HIH/PUBHORT - Needs Assessment Evaluation to Inform Statewide Horticulture Newsletter
Thursday September 26, 2024 12:00pm - 12:10pm HST
The Kansas State University Horticulture Newsletter is distributed to over 5,000 subscribers on a weekly basis for 50 weeks every year. The purpose of the newsletter is primarily educational, informing Kansas residents of the proper timing for garden-related tasks such as planting and maintenance. Other timely hot topics such as disease, pest monitoring and control methods are also provided. In January 2024 a needs assessment was deployed to all subscribers to evaluate their gardening behaviors and newsletter preferences. Almost 200 subscribers responded during the six weeks the needs assessment was available. Results indicate the primary audience is female (62%) over 60 years old (65%). Most subscribers (57%) use the newsletter to support their home gardening practices while 28% use it to support their community. Seventy-five percent of subscribers access the newsletter through the email distribution. Readers were asked their preferences for content they would like to receive in the newsletter. Thirty percent of subscribers rank vegetables as the topic of highest importance. The second highest ranked topic (18%) is garden spotlight content which features specific gardening practices of gardeners across the state. Sustainable gardening practices is the topic most requested to be added into future newsletters. This presentation will share details about providing an electronic resource to support gardeners and extension agents statewide.
Speakers
CD

Cynthia Domenghini

Kansas State University
Thursday September 26, 2024 12:00pm - 12:10pm HST
Kahili

12:00pm HST

VCM 3 - Fertility Management in Soilless Growth Media for Beet Crop Production.
Thursday September 26, 2024 12:00pm - 12:10pm HST
Greenhouse production is experiencing a rise, with more emphasis being placed on sustainability and efficient resource utilization. Accurate fertilizer applications are now more crucial than ever across various production systems. Soilless growth media possess different physical and chemical properties compared to soil, resulting in differences in nutrient retention capabilities. Because of this, it is imperative to apply precise fertilizer rates. This study evaluated 14 fertilizer blends with varying nitrogen (0-120ppm), phosphorus (0-120ppm), and potassium rates (0-120ppm). ‘Red Ace’ beet seeds were planted into 1-pint pots with Berger BM6 and plants were hand watered weekly with each treatment fertilizer rate to a 10% leaching fraction. Dry shoot weight, fresh root weight, dry root weight, number of leaves, and SPAD were taken as end measurements. This study found that high rate of nitrogen increased fresh shoot weight, while higher rates of potassium increased root weight. More studies should be done to dial in fertilizer rates for different specialty crops grown soilless greenhouse media.
Speakers
BW

Bryce Waugh

Grad Student, Oklahoma State University
Co-authors
BD

Bruce Dunn

Oklahoma State University
Thursday September 26, 2024 12:00pm - 12:10pm HST
South Pacific 4

12:00pm HST

WCPM 2 - Evaluating Bacterial Diversity and Pest Control Efficacy of Steam Disinfestation Treatments in the Salinas Valley Spinach and Lettuce Fields
Thursday September 26, 2024 12:00pm - 12:10pm HST
As the specter of climate change looms larger, sustainable and environmentally friendly alternatives for pest and pathogen control in agriculture are becoming increasingly imperative. Steam disinfestation, once an antiquated method overshadowed by chemical pesticides, is experiencing a resurgence due to heightened environmental concerns. Despite its historical use, there has been limited exploration of scaling up steam disinfestation for field applications in vegetable crops. Therefore, there is a central focus in this project to evaluate the efficacy of band steaming for disinfestation in spinach and lettuce fields in the Salinas Valley. This study seeks to advance the validation of banded steaming as a practical alternative to chemical fumigation by conducting a comprehensive assessment of vegetable productivity in lettuce grown in steamed soils versus non-steamed soils. The experiment utilized a custom-built steam applicator equipped with a low-pressure 1,000 kg/hour steam generator in Salinas, CA, during 2023. All research and trials were conducted at the Salinas Extension and USDA Center. In addition to evaluating efficacy of steam disinfestation for pest control, a preliminary evaluation of its impact on the soil microbiome was conducted on spinach and lettuce fields. Soil samples were collected before and after steam application, and crops were meticulously monitored for soil-borne disease and weed control, alongside yields at harvest. Preliminary results indicate effective weed control and lower pathogen pressure after steam treatments. Furthermore, the trials conducted from July 2023 to September 2023, involved verifying the performance of the steam applicator treatments, and assessing beneficial soil organisms using 16S sequencing in the spinach and lettuce fields. Through a thorough analysis of the outcomes derived from these trials, our objective is to offer in-depth insights into the overall efficacy of steam disinfestation and its potential implications for agricultural practices. This investigation is particularly focused on assessing its impact on the soil microbiome, the presence of pathogens, and its effectiveness in weed control.
Speakers
EE

Erika Escalona

graduate student, UC Davis
Co-authors
Thursday September 26, 2024 12:00pm - 12:10pm HST
South Pacific 2

12:00pm HST

NUTS 2 - A Look at Heat Stress on Micro-propagated Pecan Trees
Thursday September 26, 2024 12:00pm - 12:15pm HST
Carya illinoinensis (pecan) belongs to the Juglandaceae family, and the native region extends from Illinois, USA to Oaxaca, Mexico. Pecan is a valuable economic crop due to its nutritious and tasty nuts, and the United States produced 275 million pounds of pecans in 2022. As temperatures are increasing it is important to understand the impact on pecan trees. By 2100, the average U.S. temperature is projected to increase by about 3°F to 12°F. Plants deal with heat stress in several different ways including the production of heat shock proteins (HSPs) and their transcription factors known as heat shock factors (HSFs). HSFs initiate the transcription of genes that encode heat shock proteins (HSPs), that deal with heat stress by initiating protein folding and aid in the repair or removal of damaged proteins. In this study, we aim to look at the genetic networks that are impacted when multiple genotypes are subjected to high-heat environments. For this study, seedstocks from multiple genotypes that span the geographic region of North America were introduced into micropropagation. These include seedstocks from ‘Elliott’, ‘Apache’, ‘Cape Fear’, ‘Mahan’, ‘Giles’, ‘Sioux’, ‘Wichita’, ‘Western’, and native seedstocks of unknown genetics from Ohio. A preliminary heat stress assay was performed on a micropropagated ‘Elliott’ line by subjecting three small trees to 43°C for two hours prior to flash freezing in liquid nitrogen and comparing these to the same clonal line (three trees) that remained at 23°C. Real time quantitative reverse transcription PCR (QRT-PCR) was performed on the heat stress and control trees. Normalized gene expression indicated that CiHSP1 expression was 2X higher in the heat-treated pecan trees than CiHSP1 expression of the control trees. The additional micropropagated seedstocks listed above are being subjected to heat stress at different temperature ranges and time intervals. The replicated assays will be analyzed using RNA-Seq and qRT-PCR to determine differential gene expression of control and heat-treated trees especially between the HSPs and HSFs. These assays will help determine the gene networks that pecan trees use as they experience heat stress and will help determine how different pecan genetics that originate in different geographic regions react to heat stress.
Speakers
avatar for Doris Alexa Arnedo

Doris Alexa Arnedo

New Mexico State University
Co-authors
AH

Angelyn Hilton

USDA ARS Southern Plains Agricultural Research Center
NA
JR

Jennifer Randall

New Mexico State University
NA
KC

Kimberly Cervantes

New Mexico State University
NA
SP

Sahithi Pulicherla

New Mexico State University
Thursday September 26, 2024 12:00pm - 12:15pm HST
Lehua Suite

12:00pm HST

Technology in Horticulture Collaboration Session
Thursday September 26, 2024 12:00pm - 1:00pm HST
A forum for discussion of potential collaborations with regards to technology in horticulture – i.e. biotechnology, UAVs, cameras, sensors, artificial intelligence, etc.
Thursday September 26, 2024 12:00pm - 1:00pm HST
Coral 4

12:00pm HST

Pi Alpha Xi Luncheon
Thursday September 26, 2024 12:00pm - 2:00pm HST
Thursday September 26, 2024 12:00pm - 2:00pm HST
Hibiscus 1

12:05pm HST

UG 2 - Perceptions of Media Literacy in Undergraduate Students and Master Gardeners
Thursday September 26, 2024 12:05pm - 12:15pm HST
Media literacy is the ability to decipher a source’s reliability and credibility. In a 2023 Axiom Market survey about home gardeners and vegetables, participants were asked, “what is the most important place to learn about new vegetables?” Only 1% of respondents said university extension service (Axiom, 2023). As online gardening resources continue to grow so does the need for accurate and reliable information. In this study, we surveyed Iowa State University undergraduate students and Master Gardeners on their perceptions of media literacy. The survey was created in Qualtrics and contained ten Likert scale questions, eight multiple choice questions, and five gardening-based case studies. In these case studies participants were asked to rank sources based on their perceived “trustworthiness.” The survey was distributed in April 2024. Across the five case studies, Iowa State University students ranked “.org” and “.edu” sources higher than sources whose domains contained “.com.” Eighty-two percent of undergraduate students responded that they have not shared incorrect information on social media. Eighty-seven percent of students consider themselves confident internet users. Eighty-four percent of students consider themselves to be media literate. Seventy-eight percent of students consider themselves media literate and confident internet users. These results indicate that undergraduate students may not fully recognize the difference between being a confident internet user and being media literate. These data will serve as a pilot to assist with the creation of a media literacy training module for undergraduate students and Master Gardeners to strengthen their critical thinking skills around online gardening resources.
Speakers
CS

Caleb Spry

Iowa State University
NA
Thursday September 26, 2024 12:05pm - 12:15pm HST
Coral 1

12:10pm HST

CHMG/HIH/PUBHORT - Master Gardener Volunteers Learn Basic Plant Research Through the A.R.T.S. Rose Evaluation Program
Thursday September 26, 2024 12:10pm - 12:20pm HST
Modern consumers prefer to purchase shrubs and trees for the home garden that can be sustainably grown without using preventative insecticides and fungicides. Roses, which are known to be high-maintenance plants, often requiring these preventative fungicides and insecticides for optimal garden performance. The American Rose Trial for Sustainability (A.R.T.S) program seeks to determine growth data of new rose cultivars that will hopefully require fewer preventative inputs. This trial was one of 13 locations from multiple regions across the country. Seventeen unknown rose cultivars were grown during 2022–2023 and 20 additional cultivars are being grown in 2023-2024, with no additional inputs beyond sufficient irrigation. Plants were installed in production beds amended with ammoniated pine bark and top-dressed with shredded pine bark mulch. A completely randomized block design with one replication per block, with 3 blocks was used. A rating system provided by the A.R.T.S. program was used and based on forty-five percent flowering, forty-five percent foliage health, and ten percent plant form. Plants were evaluated twice monthly from April through November by 2 two-person Master Gardener teams for 2 years. Evaluations are submitted electronically in real-time directly to the national trial site manager. This trial/research opportunity allows Master Gardeners first-hand knowledge of how basic plant research in conducted. The regional and national winning selections from will be released at the conclusion of each two-year trial.
Speakers
avatar for Jeff Wilson

Jeff Wilson

Mississippi State University Extension
Thursday September 26, 2024 12:10pm - 12:20pm HST
Kahili

12:10pm HST

VCM 3 - Adaptation of AgRobotics for Onion Production in High Organic Matter Soils
Thursday September 26, 2024 12:10pm - 12:20pm HST
The high organic matter soil (50 -80%) in the Holland Marsh, Ontario, Canada, is ideal for growing root and bulb vegetables but weeds also thrive. There are few registered herbicides and increasing herbicide resistance necessitates hand-weeding, but labor shortages and increased costs increase the interest in alternative methods. The solar-powered FarmDroid FD20 is one option, if adapted to work in vegetables. The FarmDroid was used to seed and weed onions on 2.8 ha of a commercial farm with weed control issues. The robot seeded 21 beds ~800 m long, with 4 single rows in each bed, and seeds 3.4 cm apart within the row, at 225 meters per hour. Seeding took 81 hours. Weeding was done with using a cultivator with metal tines to remove weeds growing between the rows it had seeded, at a speed of 500 m/hr. Weed counts were consistently higher in the robot-weeded than conventional-farmed sections (408 and 186 weeds/m, respectively), largely because of the inability of the robot to weed within the rows. There were no differences in yield. Small scale trials were conducted to compare conventional seeding of four double rows, with single rows as above and clusters of 3 seeds, 12 cm apart in the row. Emergence was 25, 35 and 17 plants/m for single, double and triple cluster seeding, respectively. There were no differences in yield at harvest (73-76 t/ha) but there were significantly more jumbo onions (42%) in those seeded in clusters, compared to the others (9 and 1%). A separate trial assessed seeding accuracy with increased speed. Emergence was highest for onions seeded at 200 m/hr with a significant decrease at speeds of 300 – 500 m/hr. Seeding in clusters shows promise for faster seeding and larger onions. Modifications to improve the configuration of tines for weeding are ongoing.
Speakers
MR

Mary Ruth McDonald

University of Guelph
Co-authors
CB

Chuck Baerisch

Haggerty AgRobotics
NA
GF

Geoffry Farintosh

University of Guelph
NA
IE

Ifesinachi Ezeh

University of Guelph
NA
KV

Kevin Vander Kooi

Univ. of Guelph
NA
KO

Kristen Obeid

Ontario Ministry of Agriculture, Food and Rural Affairs
NA
Thursday September 26, 2024 12:10pm - 12:20pm HST
South Pacific 4

12:10pm HST

WCPM 2 - Development of Minirhizotron for Nondestructive Rapid Detection of Parasitic Nematodes
Thursday September 26, 2024 12:10pm - 12:20pm HST
Plant-parasitic nematodes are a historic problem in a wide range of horticultural and agronomic production conditions. Many horticultural crops can be negatively impacted during production since near-ideal environmental conditions are created for nematode growth and reproduction. Once established in the soil of a nursery, orchard, or greenhouse, there is also potential to spread the plant damaging nematodes via machinery, handheld equipment, soil movement, or footwear. Nematode presence may be detected by root visual symptoms of infected plants, but laboratory nematode assays are a more reliable diagnostic tool – however costly and time consuming. Our team developed a portable handheld infrared thermography-minirhizotron device for rapid, nondestructive detection of the presence or absence of plant parasitic nematodes. This self-contained device, using infrared thermography, processes images using an algorithm. It can be operated by trained personnel to perform on-site rapid diagnosis in a nursery environment. A prototype has been constructed and tested in laboratory setting. It is equipped with wireless communication and network capabilities, allowing remote access and control. The goal is to develop a smart device that can be scaled up and networked for early detection and rapid response to a wide range of soil nematodes of horticultural importance. The algorithm is developed to distinguish between root-knot and cyst nematodes in infected plants.
Speakers
TP

Tim Pannkuk

Sam Houston State University
Co-authors
AS

Autumn Smith-Herron

Sam Houston State University
NA
FY

Faruk Yildiz

Sam Houston State University
NA
JM

Junken Ma

Sam Houston State University
NA
RP

Recayi Pecen

Sam Houston State University
NA
Thursday September 26, 2024 12:10pm - 12:20pm HST
South Pacific 2

12:14pm HST

Genetics and Germplasm 2 (GG 2)
Thursday September 26, 2024 12:14pm - 1:25pm HST
Exploration of Salt-Tolerant Germplasm to Increase Specialty Rice Production in South Carolina - Gursewak Singh
Independent Domestication of Cucumber (Cucumis sativus L.) Fruit Revealed by Cucurbitacin and Volatile Compound Profiling - Eun Jin Lee
Evaluation of watermelon and Citrullus crop wild relatives for resistance to whiteflies and whitefly transmitted viruses - Alexander Luckew
Development of Specialty Pumpkin Cultivars with Potential to be Released for Organic and Conventional Resilient Cropping - Angela Linares Ramirez
SSR Marker Development and Fine Mapping of Linkage Group 2 Eastern Filbert Blight Resistance from ‘Georgian OSU 759.010’ - Brianna Heilsnis
Enhancing the Fruit Set of NJ BP1-1 Beach Plum (Prunus maritima) - Megan Muehlbauer
The wonderful world of worms: Microbiota of rabbit manure vermicompost at different maturities - Amanda Birnbaum
Moderator
GS

Gursewak Singh

Clemson University
Thursday September 26, 2024 12:14pm - 1:25pm HST
Nautilus 1

12:14pm HST

Plant Nutrient Management (PNM)
Thursday September 26, 2024 12:14pm - 1:35pm HST
Aerated Compost Tea Impacts on Soil Parameters and Yield of Tomato, Carrot, and Beet - Charlie Rohwer
The Effect of High Concentrated Liquid Fertilizer at Hydroponic Culture to the Contents of Amino Acids and Mineral in Watermelon Fruits - Sentaro Tomiyama
Changes Of Fruit Profile And Content Of Carotenoids At Different Nutrient Conditions In Hydroponically Grown Watermelon - Xiangyu Cui
Phosphorus Fertilizer Application Strategies to Improve Phosphorus Availability and Utilization in Potatoes. - Samuel Essah
Nitrate Leaching in Processing Tomato Production Subjected to Deficit Irrigation and On-Demand Nitrogen Fertilization - Dave Goorahoo
Greenhouse Nitrogen application rate optimization for optimal bamboo (Dendrocalamus asper) growth and productivity in Florida - Cyrus Januarie
Determining Adequate Nutrient Application Rates for Water Spinach (Ipomoea aquatica) Production in Deep Water Culture - Shelbie Bohensky
The incorporation of black soldier fly larvae to fish feed increased fish and plant growth - Most Tahera Naznin
Moderator
avatar for Dave Goorahoo

Dave Goorahoo

Professor, California State University, Fresno
Thursday September 26, 2024 12:14pm - 1:35pm HST
South Pacific 1

12:14pm HST

Postharvest 2 (PH 2)
Thursday September 26, 2024 12:14pm - 2:00pm HST
Non-invasive Assessment of Haskap Growth (Lonicera caerulea) Utilizing X-ray Computed Tomography and Image Processing - Arturo Duarte Sierra
Vase Life Prediction for Cut Roses Using Deep Learning and Hyperspectral Imagining Techniques - Yongtae Kim
Extending the Postharvest Storage of Caladium Tubers to Unlock Late-Season Pot Plant Production Potential in Florida - Gasselle Cordova
Analysis of Oxidative Decreases in Hop (Humulus lupulus L.) Bitter Acids Produced Postharvest - Katie Stenmark
The Use of Desiccants for Proper Moisture Preservation in Green Coffee During Storage and Transportation - Laudia Anokye Bempah
Transcriptome Analysis Revealed that Metabolites and Hormone Signaling Pathway Differently Respond to Non-chilling and Chilling Temperatures in Cucumber (Cucumis sativus L.) Fruit During Storage - Yujin Sim
Fresh Weight of Indoor-Grown Lettuce under Different Postharvest Storage Practices -Caroline Blanchard
Modified Hydrocooling and Optimized Postharvest Handling Practices Can Improve the Shelf Life of Water Spinach During Summer in Humid Subtropical Regions - Wei Shiang Liao
Discovery of Biomarkers for Postharvest Pecan Color Stability Using Metabolomics and Machine Learning Algorithms - Min Jeong Kang
Evaluating the Effects of Controlled Atmosphere Storage on Two Georgia-grown Pecan Cultivars - Ramsey Corn

Moderator
DA

Duarte-Sierra Arturo

Université Laval
Thursday September 26, 2024 12:14pm - 2:00pm HST
South Pacific 3

12:14pm HST

Water Utilization and Management 3 (WUM 3)
Thursday September 26, 2024 12:14pm - 2:15pm HST
Assessing Grapefruit Responses to Different Irrigation Rates for Managing Salinity Water Under Greenhouse-Controlled Conditions - Neus Alcon Bou
Irrigation trials examine yield, water productivity, and nitrogen uptake of summer cauliflower - Michael Cahn
Growth Morphology as Indicators of Salt Water Tolerance in Watermelon Cultivars - Azeezahmed Shaik
Assessment of Salinity Tolerance in Cucumber Cultivars Using NFT System - Azeezahmed Shaik
Influence Of Deficit Irrigation And Biochar Application On Soil Water Depletion, Roots Distribution, And Water Use Efficiency Of Cucumber - Sukhbir Singh
Assessing Resource-use Efficiency Affected by Irrigation Management Practices in Processing Onion Production - Ali Montazar
Glyphosate Runoff Impacting Water Quality - Natalie Santos
Assessing Drip Irrigation as an Alternative to Micro-sprinklers During Strawberry Establishment in Southern California - Andre Biscaro
Moderator
AB

Andre Biscaro

UC Cooperative Extension
Thursday September 26, 2024 12:14pm - 2:15pm HST
Coral 2

12:15pm HST

GG 2 - Exploration of Salt-Tolerant Germplasm to Increase Specialty Rice Production in South Carolina
Thursday September 26, 2024 12:15pm - 12:25pm HST
The significance of Carolina Gold specialty rice in South Carolina's (SC) agricultural history is deeply rooted, dating back to colonial times. Its unique flavor and texture have made it a prized variety among chefs and food enthusiasts. Currently, saltwater intrusion and weed infestation threaten this specialty rice production in SC. Understanding salt tolerance and weed interactions is crucial for ensuring the continued production and quality of this specialty rice. Preliminary experiments assessed the impact of different concentrations of ocean water and native weed pressure on rice plant vigor when cultivated organically under controlled environmental conditions. In brief, we screened rice germplasm under various seawater concentrations (0, 0.375, 0.75, 1.5%, and 3%) in both weed-free and weed competition conditions. In our preliminary greenhouse studies, we observed weed competition reduced the rice plant biomass by 2-3 times and yield up to 5 times at a 3% seawater concentration. M202 and Doble Carolina exhibited the highest salt tolerance and higher photosynthesis rate when compared to local genotypes, Carolina Gold and Santee Gold. The cultivars demonstrating superior performance under these conditions were subsequently subjected to further testing in organic research plots, incorporating supplemental irrigation with tidal ocean water. A field experiment was designed to evaluate and validate the salinity tolerance of six rice genotypes (Carolina Gold, Santee Gold, Doble Carolina, M202, Jupiter, and JN100) under different seawater concentrations (0%, 1.5%, 3%, 6%, and 12%), both in weed-free and weed-competition scenarios. Using a gasoline pump, we collect brackish water from the adjacent marsh in a 4000-gallon-capacity reservoir/pool. The calculated volumes are then pumped into the field plots based on each plot's fresh and seawater volumes. The salinity level of treated plots is monitored by measuring the EC values. The results indicated that M202, Doble Carolina and JN100 showed the highest salt tolerance. Weed competition reduced the rice plant height, number of tillers, panicles, dry root, and shoot weight across the entire salinity gradient. Weed competition led to an approximately 50% reduction in both the aboveground (shoot) and belowground (root) weights of rice plants, as compared to weed-free plots, across the tested salinity levels. Weed biomass, weeding time and regrowth of weeds declined significantly above 3 % seawater concentration when compared to control. Eventually, the most promising cultivars identified are being incorporated into a breeding program to integrate salt-tolerant genes into the Carolina Gold specialty rice.
Speakers
GS

Gursewak Singh

Clemson University
Co-authors
BW

Brian Ward

Clemson University
JR

Jai Rohila

USDA-ARS
NA
MM

Michael Marshall

Clemson University
NA
RK

Raghupathy Karthikeyan

Clemson University
NA
SW

Sarah White

Clemson University
NA
Thursday September 26, 2024 12:15pm - 12:25pm HST
Nautilus 1

12:15pm HST

PH 2 - Non-invasive Assessment of Haskap Growth (Lonicera caerulea) Utilizing X-ray Computed Tomography and Image Processing
Thursday September 26, 2024 12:15pm - 12:25pm HST
The latest advances in technology have made it easier to accurately assess the quality of fresh produce, reducing the amount of physical handling required. Computed tomography (CT) is a non-intrusive method that can effectively monitor and categorize fresh produce at different stages of development and maturity. Implementing novel CT scanning techniques can provide innovative means for classifying fresh produce in the early stages of development. The present work provides information for the calculation of the volume and the porosity of the haskap during its ontology. Samples of haskap were taken at four stages of growth prior to harvest and at the time of harvest. Image data were acquired using X-ray microcomputed tomography (SkyScan 1272, Bruker, Billerica, MA, USA) at a resolution of 19.69 μm per pixel, operating at 60 kV and 166 μA, using a 0.25 mm aluminum filter. The resultant data was exported to the BMP file format. BMP files were then processed using Avizo 3.0 (Thermo Fisher Scientific, Waltham, Massachusetts, USA). Automated thresholding using factorization in criteria was applied to the 8-bit images. Subsequently, the images were labeled and an axis connectivity of 26 neighborhoods was established. Finally, a measurement was derived using the volume fraction tool. The results showed that the porosity at stage 3 was 26.56%. It then decreased to 7.52% in the 4th stage and reached a peak of 13.45% during the harvesting stage. These results may have implications for commercial cultivation strategies and optimization of pre- and post-harvest practices and add to the existing understanding of Haskap growth and development.
Speakers
DA

Duarte-Sierra Arturo

Université Laval
Co-authors
CG

Charles Goulet

Université Laval
NA
EA

Ernesto Alonso Lagarda Clark

Université Laval
NA
Thursday September 26, 2024 12:15pm - 12:25pm HST
South Pacific 3

12:15pm HST

PNM - Aerated Compost Tea Impacts on Soil Parameters and Yield of Tomato, Carrot, and Beet
Thursday September 26, 2024 12:15pm - 12:25pm HST
The intentions of aerated compost tea are to provide nutrients to plants or beneficial microbes to the soil or phyllosphere. Compost tea may also contain organic compounds which alter plant physiology (growth or induced defenses). Compost tea is mainly encountered in organic systems, but there is evidence for improved outcomes when using both organic and conventional nutrient sources. The objective of this study is to understand more about the impacts of aerated compost tea (ACT) on soil microbial activity and nitrogen status and plant responses. ACT was applied weekly or bi-weekly as a drench or as a spray to field-grown tomatoes, carrots, and beets fertilized organically or conventionally at two locations in Minnesota. Results presented here focus on produce yield from year 1 of the 3-year study. We found no difference in any of the yield parameters measured due to compost tea application. We generally observed higher yields in organically-fertilized produce in both locations. One location, with a longer history of organic production, had higher soil microbial activity in the organically-fertilized treatment but the difference in yield between conventional and organic tomatoes was similar at both locations.
Speakers
avatar for Charlie Rohwer

Charlie Rohwer

Scientist, University of Minnesota
Co-authors
EE

Emily E Evans

University of Minnesota
NA
LK

Lee Klossner

University of Minnesota
NA
PP

Paulo Pagliari

University of Minnesota
NA
Thursday September 26, 2024 12:15pm - 12:25pm HST
South Pacific 1

12:15pm HST

UG 2 - Identifying the Role of the Chloroplast-Mediated CEBP Transcription Factor in Petunia Flower Senescence
Thursday September 26, 2024 12:15pm - 12:25pm HST
The Carnation Ethylene-responsive element-Binding Protein (CEBP), a nuclear-encoded transcription factor found in plants, is believed to be involved in the senescence of flowers. Previous studies have elucidated the putative role of this protein in the nucleus, however the role of CEBP in the chloroplast remains unknown. An RNAi construct to silence CEBP mRNA expression was developed under control of the Clarkia breweri linalool synthase (LIS) promoter, a flower specific promoter, in addition to Kanamycin resistance. The construct was transformed into E. coli, and then the plasmid containing the construct was then transferred into Agrobacterium. Next, Agrobacterium mediated transformation was utilized to insert the RNAi into the petunias using leaf disk infiltration. Four independent transgenic lineages were transferred from tissue culture to the greenhouse. QRTPCR confirmed expression of the RNAi construct as well as knock down effect on CEBP expression. Senescence timeframes, physiological changes, and downstream effects will be reported.
Speakers
CK

Colin Krisulevicz

West Virginia University
Co-authors
JL

Joseph Lynch

West Virginia University
NA
SJ

Sven J Verlinden

West Virginia University
Thursday September 26, 2024 12:15pm - 12:25pm HST
Coral 1

12:15pm HST

NUTS 2 - Unraveling the role of LEA(Late embryogenesis abundant) genes in pecan stress resilience
Thursday September 26, 2024 12:15pm - 12:30pm HST
Late embryogenesis abundant (LEA) proteins, encoded by a family of LEA genes, are vital in conferring stress tolerance in plants through their unique intrinsically disordered structure that can stabilise cellular components under desiccated conditions. While the protective capabilities of LEA proteins are well-documented across various crops, their specific roles in pecan (Carya illinoinensis), a highly nutritious and economically significant nut crop, remain largely unexplored. This gap of knowledge needs to be addressed as pecan yields face threats from escalating drought and salinity issues, intensified by ongoing climate change. This study represents the first comprehensive analysis of LEA genes within the pecan genome. We have successfully identified 332 LEA genes distributed across 15 of the 16 chromosomes in four genomes of pecan, categorized into 8 distinct subgroups based on their conserved motif regions. Synteny analysis provided a deeper understanding of their evolutionary trajectories. Utilizing extensive transcriptomic datasets, we explored the tissue-specific expression patterns of LEA genes in pecan, discovering diverse expression profiles across various tissues. Ongoing studies include promoter analysis and assessments of gene expression under abiotic stress conditions. To specifically address the impact of drought, heat and salinity, clonal pecan plants are being subjected to these stressors under controlled conditions in tissue culture and greenhouse settings. This approach aims to directly observe the physiological and molecular responses of LEA genes under realistic stress simulations. The presence of LEA genes across a vast majority of pecan chromosomes and their diverse subgroup classifications suggests a genome-wide defense mechanism potentially key to enhancing the stress tolerance of pecan trees. By understanding and harnessing these genes, our research seeks to elucidate plant stress responses at the molecular level allowing the development of genetic strategies to ensure the sustainability of pecan by mitigating adverse environmental impacts on its production. This knowledge could also be applied in a diverse array of other economically significant crops.
Speakers
SP

Sahithi Pulicherla

New Mexico State University
Co-authors
AA

Alexa Arnedo

New Mexico State University
CM

Chris Mattison

United States Department of Agriculture
NA
JR

Jennifer Randall

New Mexico State University
NA
Thursday September 26, 2024 12:15pm - 12:30pm HST
Lehua Suite

12:15pm HST

WUM 3 - Assessing Grapefruit Responses to Different Irrigation Rates for Managing Salinity Water Under Greenhouse-Controlled Con
Thursday September 26, 2024 12:15pm - 12:30pm HST
Coastal agriculture frequently relies on surface water for irrigation. However, in Florida, surface water availability can become limited during the dry season, leading growers to switch to groundwater. Groundwater in coastal areas often contains high salt concentrations which can negatively affect crop production. Citrus species, one of the most cultivated crops in Florida, are sensitive to salt stress. Among other strategies, irrigation management is used to mitigate salinity buildup in soil by leaching salts away from the root zone. Increased irrigation rates with water sources in the ‘slight’ to ‘moderate’ range of salinity (0.7 to 3 dS/m) have been shown to reduce salt accumulation in the soil without affecting production. However, when the water has high salinity concentrations (>3 dS/m), increasing the irrigation rate beyond 125%-130% of the crop evapotranspiration (ETc) is not sustainable due to the high-water usage. Conversely, a limited volume of water applied for leaching the salts can exacerbate the accumulation. In coastal Florida, where often only high salinity water is available during the dry season, evaluating short-term strategies to maintain crop production is crucial. The objective is to understand how irrigation water with high salinity concentrations and different irrigation rates impact plant performance and soil salinity accumulation. In this study, one-year-old ‘Ruby Red’ grapefruit trees grafted on ‘US-942’ rootstock were planted in a weighing lysimeter phenotyping platform (“Plant Array”) under greenhouse-controlled conditions. Irrigation water with high salinity concentration (5 dS/m) was precisely applied at three different irrigation rates: 75% (deficit), 100% (regular), and 125% (excessive) of the ETc. A control treatment with water at a low salinity concentration (0.3 dS/m) was applied at 100% ETc for comparison. Transpiration, plant net weight, soil moisture and soil electrical conductivity (EC) were recorded daily. Bulk leaf water potential, osmotic potential, and dark-adapted chlorophyll fluorescence were measured at the beginning and at the end of the experiment. Results showed that ETc and net weight decreased for those plants irrigated with high salinity concentration compared to the control. Salt EC was higher for those trees irrigated with 75% ETc under high salinity concentration resulting in the lowest ETc rates. Plants irrigated with 100% and 125% ETc rates showed similar results, likely due to decreasing transpiration of trees upon high salinity treatment application. Different plant performance under different irrigation rates emphasized the need of evaluating irrigation strategies in mitigating salt stress in citrus, particularly in region with limited water resources.
Speakers
NA

Neus Alcon Bou

University of Florida
Co-authors
GS

Gerard Sapes

University of Florida
NA
JF

John-Paul Fox

University of Florida
LR

Lorenzo Rossi

University of Florida
SG

Sandra Guzman

University of Florida
NA
WH

William Hammond

University of Florida
NA
Thursday September 26, 2024 12:15pm - 12:30pm HST
Coral 2

12:20pm HST

CHMG/HIH/PUBHORT - 5 Year Study Demonstrates Increased Health and Wellbeing Among Master Gardener Volunteers
Thursday September 26, 2024 12:20pm - 12:30pm HST
Master Gardener Volunteers (MGV) are a highly trained corps of volunteers whose mission is to assist extension agents in providing research-based horticultural information and education to residents. MGV’s accomplish this through participating in a variety of volunteer activities including gardening, youth and adult education, writing articles, testing soil pH, and providing diagnostic services at plant clinics. An objective of this program is that 75% of MGVs will report improved wellbeing as a result of participating in the MGV program. Annual surveys have been distributed from 2019 to 2023 to access the benefits derived from participating in the program both as a volunteer and specifically as a volunteer in a garden setting. Results from 5 years of annual surveys revealed that as a result of participating in the MGV program: 87% (n=168) feel physically healthier; 77% (n=170) experienced reduced levels of stress; 88% (n=171) experienced improved mental health; 78% (n=169) increased social connectedness; 88% (n=171) increased overall life satisfaction; and 91% (n=170) feel they make a difference in their community. When these MGVs were surveyed about their experience specifically volunteering in a garden setting, 90% (n=132) reported improved mental health; 86% (n=136) increased social connectedness; 81% (n=131) increased energy and vitality; 91% (n=132) increased sense of wellbeing; 84% (n=132) improved outlook on life; 96% (n=131) increased physical activity; and 90% (n=131) improved physical health. Volunteers experience improved health and wellbeing from participating in the MGV program and from gardening opportunities the affiliation provides.
Speakers
TF

Terra Freeman

Urban and Commercial Horticulture Extension Agent, University of Florida
Thursday September 26, 2024 12:20pm - 12:30pm HST
Kahili

12:20pm HST

VCM 3 - Effect of Mineral Nitrogen and Foliar Spraying of Humic Acid on Fresh and Dry Leaves and Roots Weights, and Root Length
Thursday September 26, 2024 12:20pm - 12:30pm HST
Lactuca sativa L., commonly known as lettuce, represents a vital winter leafy vegetable crop cultivated globally, including Libya, owing to its rich nutritional content and rapid growth characteristics. Enhancing the vegetative growth of lettuce and similar leafy crops often involves employing various horticultural practices, with fertilization being a key component utilizing diverse nutrient sources. Two field experiments conducted at the Department of Horticulture Farm, Omar Al-Mukhtar University, situated in Al-Jabal Al-Akhdar region of Libya in 2021 and 2022 aimed to evaluate the effects of ground-applied urea fertilizer (46% nitrogen) at rates of 0, 60, 120, and 180 kg.ha⁻¹, combined with foliar applications of different concentrations of humic acid (0, 1, 1.5, and 3 ml.L⁻¹), on the fresh and dry weights of leaves and roots, as well as root length of lettuce cv. Nickerson-Zwaan plants under local environmental conditions. Each experiment comprised 16 treatments representing all possible combinations of the two factors and followed a randomized complete block split-plot design with four replications per treatment. Results revealed that increasing levels of mineral nitrogen and humic acid resulted in a significant increase of fresh and dry weights of lettuce leaves and roots across both growing seasons as compared to the control treatment, with consistent effects observed for the interaction between nitrogen fertilization sources and their respective rates. While no significant impact was observed on root length due to urea fertilizer or humic acid spray in either growing season, application of 180 kg.ha⁻¹ urea fertilizer in the second season showed a tendency towards greater root length compared to other treatments. Thus, the findings suggest that the application of mineral nitrogen fertilizer and humic acid spray holds promise for enhancing the vegetative growth of lettuce plants in Al-Jabal Al-Akhdar region of Libya.
Speakers
AO

Ali Omar

Omar Al-Mukhtar University
Thursday September 26, 2024 12:20pm - 12:30pm HST
South Pacific 4

12:20pm HST

WCPM 2 - Genome Sequencing of Crapemyrtle Bark Scale for Developing Advanced IPM Strategies
Thursday September 26, 2024 12:20pm - 12:30pm HST
Crapemyrtle bark scale (CMBS; Acanthococcus lagerstroemiae), an invasive insect pest threatening horticultural industries, has spurred the search for sustainable control methods. Our recent research focused on two key aspects of CMBS behavior: feeding and mating. In feeding, our studies revealed that while nicotine does not affect the phloem salivation process in CMBS, it significantly impairs the insect’s ability to ingest phloem sap, suggesting that nicotine interferes with the precise muscular coordination in the acephalothoracia region of CMBS, thereby offering a potential mechanism for chemical control. By identifying the genes that encode nicotinic receptors, we can pinpoint potential chemical targets to disrupt CMBS feeding behavior. In studying mating behavior, we found that mating is crucial for CMBS reproduction. Solid-phase micro-extraction and GC/MS assays revealed that CMBS release unique volatile compounds at different life stages. By identifying the genes responsible for sex pheromone production and pheromone receptors, our research lays the groundwork for developing pheromone-based traps and mating disruption strategies. Moreover, the discovery of juvenile hormone receptors and their expression at various developmental stages suggests additional opportunities to hinder CMBS growth and reproduction. We are conducting a comprehensive genomic analysis of CMBS using PacBio SMRT, Hi-C, and Illumina genome sequencing. This genomic framework will be used to develop innovative pest control strategies to control CMBS populations while supporting integrated pest management (IPM) techniques and reducing environmental impact.
Speakers
BW

Bin Wu

Texas A
My integrated research and Extension programs focus on the evaluation, selection, and breeding of horticutlural specialty crops, as well as the study of insect-plant interactions and natural enemies. The goal is to develop integrated pest management (IPM) strategies for controlling... Read More →
Co-authors
HQ

Hongmin Qin

Texas A
NA
HD

Hui Duan

USDA
NA
MP

Margaret Pooler

Floral and Nursery Plants Research Unit, U.S. National Arboretum, U.S. Department of Agriculture-Agricultural Research Service
NA
Thursday September 26, 2024 12:20pm - 12:30pm HST
South Pacific 2

12:25pm HST

GG 2 - Independent Domestication of Cucumber (Cucumis sativus L.) Fruit Revealed by Cucurbitacin and Volatile Compound Profiling
Thursday September 26, 2024 12:25pm - 12:35pm HST
Cucumber (Cucumis sativus L.) fruit has characteristic taste and aroma, the important organoleptic qualities influencing consumer preference and marketability. Profiling of metabolites conferring bitterness and aroma is required to improve cucumber fruit quality and produce preferred fruit. In this study, we profiled cucurbitacins responsible for bitterness and volatile compounds using fruit of 69 cucumber genotypes with different fruit shape, color, and origin and provided qualitative and quantitative information of metabolites involved in the organoleptic quality. Among six types of cucurbitacis (CuA-E, I), only CuC was detected in six inbreds while most genotypes didn’t contain them. It means bitterness has been lost in modern cucumber cultivars with domestication process. The 69 genotypes were classified into four clusters according to the profiles of cucurbitacins and volatile compounds. Clusters 2 and 3 accumulated the highest and lowest volatile contents, respectively. Clusters 1 and 4 were discriminated by minor volatiles rather than major ones, suggesting they have distinct background flavor. Clusters 1 and 4 also showed different phenotypes such as length and color, implying a relationship between fruit phenotype and background flavor. However, the clustering was inconsistent with cultivar types or origins. It suggests independent domestication for bitterness and flavor has been conducted for cultivars in different origins. We further examined hybridization effect on metabolite compositions using 15 F1 hybrids from selected inbreds. Total volatile compound (TVC) content was reduced in the F1 hybrids, especially due to decrease in total alcohol content affecting increase in ratio of aldehyde to TVC. These findings will contribute to improvements of cucumber organoleptic qualities and will provide useful information for selecting cucumber materials to produce preferred fruit.
Speakers
EJ

Eun Jin Lee

Seoul National University
Co-authors
JK

Jeongyun Kim

Dankook University
NA
KM

Kyeonglim Min

Seoul National University
Thursday September 26, 2024 12:25pm - 12:35pm HST
Nautilus 1

12:25pm HST

PH 2 - Vase Life Prediction for Cut Roses Using Deep Learning and Hyperspectral Imaging Techniques
Thursday September 26, 2024 12:25pm - 12:35pm HST
Japan is a major export market for the Korean cut rose flower industry. The longevity of cut roses significantly influences consumer purchasing decisions, prompting Japan to establish a quality guarantee system to ensure cut flower longevity. However, existing longevity guarantee methods rely heavily on subjective evaluations, overlooking critical factors such as senescence characteristics and disease infections. Hyperspectral imaging (HSI) technique is used for quality control of many fruits and can be performed at video rates, and could thus provide accurate data on aspects of cut flower quality. The You Only Look Once version 8 (YOLOv8) and Random Forest models for object detection and classification enable consistent quality assessment and swift longevity prediction. In this study, we developed a non-contact and rapid detection technique for the potential longevity of cut roses using deep learning techniques based on HSI data. Cut ‘Unforgettable’, ‘Egg Tart’, and ‘Catalina’ rose flowers were held in wet conditions during the exportation to Japan. HSI data within the visible near-infrared range 450-900 nm wavelengths were obtained for analysis of the disease infection and quality of cut roses. Image data of diseased cut roses were collected and corresponding data processing was carried out to build diseased cut roses and quality detection dataset. We developed the longevity prediction model based on scoring a grading standard on the flower quality and this model was then used to predict the longevity and evaluate quality changes of cut roses after exporting to Japan. The results showed that the longevity of exported cut roses was 8 d (‘Egg Tart’), 5.9 d (‘Catalina’), and 4.9 d (‘Unforgettable’). The longevity of cut roses was primarily terminated by gray mold disease (‘Unforgettable’ and ‘Catalina’), petal wilting and discoloration (‘Egg Tart’ and ‘Catalina’), and petal abscission (‘Catalina’). The predictive accuracy of the three rose flowers longevity prediction model was three rose flowers ‘Egg Tart’ (r2=0.80), ‘Unforgettable’ (r2=0.78), and ‘Catalina’ (r2=0.65). These results demonstrate that the combination of HSI and deep learning is a reliable method for evaluating the longevity of exported cut roses.
Speakers
YK

yongtae kim

Andong National University
Co-authors
BI

ByungChnu In

Andong National University
NA
JY

Ji Yeong Ham

Andong National University
ST

Suong Tuyet Yhi Ha

Andong National University
NA
Thursday September 26, 2024 12:25pm - 12:35pm HST
South Pacific 3

12:25pm HST

PNM - The Effect of High Concentrated Liquid Fertilizer at Hydroponic Culture to the Contents of Amino Acids and Mineral in Watermelon Fruits
Thursday September 26, 2024 12:25pm - 12:35pm HST
We have previously reported the sugar distribution and accumulation in watermelon fruit grown hydroponically (Tomiyama et al. 2023 . Hort Science). In this research, the contents of amino acids and mineral in watermelon fruits grown hydroponically at high concentrated nutrient solution were investigated. Three different hydroponic culture conditions were set by Electric Conductivity: EC 5.0, 3.0, and 1.2 dS-m-¹. Initially watermelon seedlings (Citrullus lanatus (Thunb.) Matsum. Et Nakai ‛Hitorijime-BonBon) were grown at EC 1.2 dS-m-¹ (Control) conditions on deep flow technique in a glasshouse. Treatment was initiated two weeks after pollination. Forty days after pollination, watermelon fruits were harvested and measured its size. Then, mineral and amino acids content were analyzed by HPLC. We measured NH⁴⁺, K⁺, Mg⁺, and Ca²⁺ as cations and PO⁴- and NO³- as anions. Twenty amino acids were measured also. As result, the fruit size and weight decreased under high nutrient conditions. At mineral analysis, the cations NH⁴⁺, Mg⁺, and Ca²⁺ content in the flesh did not increase at the high concentrated treatment, but K⁺ increased in the pericarp at higher treatment. Similarly, the anions PO⁴- and NO³- content increased as K⁺. In control, amino acids was accumulated in the center of flesh, whereas in the higher concentration amino acids was concentrated in the pericarp. When we focused on citrulline and proline, they were accumulated more in pericarp than flesh. In conclusion, mineral (K⁺, PO₄³-, NO₃-)and some amino acids such as citrulline, and proline, which accumulate in the pericarp, accumulated under high concentrated liquid fertilizer at hydroponic culture.
Speakers
ST

Sentaro Tomiyama

Meiji University
Co-authors
MO

Masako Osawa

Hagihara farm
NA
SF

Shingo Fujita

Hagihara farm
NA
TI

Takashi Ikeda

Meiji University
NA
XC

Xiangyu Cui

Meiji University
YM

Yusuke Matsumoto

Meiji University
NA
Thursday September 26, 2024 12:25pm - 12:35pm HST
South Pacific 1

12:25pm HST

UG 2 - Optimal production densities and storage conditions for five microgreens
Thursday September 26, 2024 12:25pm - 12:35pm HST
Microgreens, or very young vegetable seedlings, are an increasingly common appearance in dishes for garnish, flavor, and even nutrient content. As microgreens become more relevant, this study analyzed the optimal density by which to sow a variety of microgreen species as well as the optimal temperatures to store them once harvested. Seeds of arugula, cilantro, red leaf beet, and Russian kale were sown at 5.27g/m2, 10.54g/g/m2, 21.10g/m2, 42.18g/m2, 84.35g/m2, 168.71g/m2, and 337.42g/m2. Sowing density was randomly assigned in a randomized complete block design with three replications. The average height was measured before harvest and fresh weight was determined upon harvest. Fresh weights of microgreens sown at 337.42g/m2 was always more than those sown at any other density. Interestingly, this treatment did not always produce the tallest plants. Lower densities, notably arugula and beet, produced the tallest plants at 21.10g/m2 and 42.18g/m2. Considering cost seed and harvestable yield, optimal sowing densities were for 168.71g/m2, and 337.42g/m2. In a separate experiment the same microgreens were stored in clamshells at 0.0°C, 2.5°C, 5.0°C, 7.5°C, 10.0°C, 12.5°C, and 20°C. Microgreens were observed at 3, 7, 10 and 14 days after harvest and rated on a 1 to 5 scale. Storage at room temperature (20°C) caused severe yellowing and quick decline where none of the microgreens were of acceptable quality at 3 days after harvest. Temperatures below 7.5°C allowed acceptable storage of each of the microgreens for up to one week. Decay was most significant in arugula at two weeks of storage while others only showed moderately better performance.
Speakers
SP

Sam Petrovich

West Virginia University
NA
Co-authors
SJ

Sven J Verlinden

West Virginia University
Thursday September 26, 2024 12:25pm - 12:35pm HST
Coral 1

12:30pm HST

CHMG/HIH/PUBHORT - Exploration of the barriers faced by minority organic farmers in Kentucky.
Thursday September 26, 2024 12:30pm - 12:40pm HST
African Americans (AA) have a rich history intertwined with agriculture, yet modern agricultural opportunities often elude them. Despite the industry
Speakers
TN

Theoneste Nzaramyimana

Kentucky State University
Dr. Theoneste Nzaramyimana is an assistant Professor for Urban Agriculture at Kentucky State University. His research interests are in developing programming to identify and provide solutions for farmers and professionals to impact the global food system. Dr. Theoneste Nzaramyimana... Read More →
Thursday September 26, 2024 12:30pm - 12:40pm HST
Kahili

12:30pm HST

VCM 3 - Dual-cropping Sweetpotato for Greens and Root Production
Thursday September 26, 2024 12:30pm - 12:40pm HST
Sweetpotato (Ipomoea batatas) is a nutritious crop that produces edible roots, stems, and leaves. The tender vine tips, including both leaves and stems, are consumed as a vegetable in many regions of the world, including the Pacific Islands, Asia, and parts of Africa. A field experiment in Mount Vernon, WA evaluated time of vine tip (15 cm from the end of every vine) harvest on sweetpotato root yield of breeding lines USDA-04-284 (semi-erect growth habit), USDA-04-136 and USDA-04-791 (both with spreading growth habit). Treatments included no harvest during the season (control treatment, 1 harvest at time of root harvest), early harvest (8–12 weeks after transplanting, 4 harvests), late harvest (12–14 weeks after transplanting, 3 harvests), and continuous harvest (8–14 weeks after transplanting, 5 harvests). Vine tips were harvested at 2-week intervals during the harvest period, with an additional harvest for all treatments (including control) immediately before root harvest. Breeding line USDA-04-284 (semi-erect growth habit) produced 330 g of greens (fresh weight) per plant on average for all harvest treatments, which was significantly higher (p
Speakers
LS

Laura Schulz

Washington State University
Co-authors
CM

Carol Miles

Washington State University
JB

Jacob Blauer

Washington State University
NA
LM

Laurel Moulton

Washington State University
NA
PW

Phil Wadl

United States Department of Agriculture, Agricultural Research Service
Thursday September 26, 2024 12:30pm - 12:40pm HST
South Pacific 4

12:30pm HST

WCPM 2 - A New Technique for Visual and Quantitative Assessment of Pesticide Applications to Tree Trunks for Control of Trunk-boring Insects
Thursday September 26, 2024 12:30pm - 12:40pm HST
Water sensitive paper (WSP), a yellow paper that stains blue in the presence of water, can be used to evaluate spray characteristics. While traditionally used as 2x3-inch cards placed in the canopy, we developed a WSP wrap that can be wrapped around a trunk, sprayed, and removed without damaging the trunk to assess spray distribution for control of trunk-boring insects. Trunk wraps are made by adhering a 1x8.5-inch strip of WSP to a 1.75x8.5-inch strip from a printable vinyl sticker sheet. To install, the adhesive is exposed, the wrap is manually wrapped around the trunk, and pressure is applied by gripping the wrapped portion of the trunk. However, the tapered shape, bumpy surface, and small trunk caliper, as well as humidity can cause wraps to unravel during experiments. In preliminary tests, 50% of uncoiled, i.e., flat, 4.25-inch wraps unraveled from 16.5 mm caliper Acer rubrum ‘Franksred’ Red Sunset® red maple trunks. Our objective was to test if pre-coiling wraps prevented unraveling. We tested four treatments with five replications each: 1. 8.5-inch wraps coiled and stored in 2-inch diameter PVC, 2. 8.5-inch uncoiled wraps, 3. 4.25-inch wraps coiled and stored in 0.75-inch PVC, and 4. 4.25-inch wraps coiled in 0.75-inch PVC and stored in 1-inch PVC. After 2 weeks of storage, we installed wraps on 16.5 mm caliper Red Sunset® trunks. After 5-10 minutes, we reapplied pressure to both 8.5-inch wraps and 4.25-inch flat wraps because they unraveled, our standard practice; both 4.25-inch pre-coiled wrap treatments remained tightly wrapped and did not require this step. After an additional 5-10 minutes we assessed whether or not wraps were tightly wrapped around trunks. All wraps within both 4.25-inch pre-coiled wrap treatments remained tightly wrapped around trunks. All 8.5-inch uncoiled wraps unraveled and 40% of 8.5-inch pre-coiled wraps unraveled suggesting a modest benefit to coiling this length and that extra length is not beneficial. Following this experiment, we successfully used pre-coiled 4.25-inch wraps on 16-19 mm caliper maple and 8.5-inch wraps on 46-52 mm caliper oak tree trunks. We observed that repeated wrap installation (approx. ≥5 times) to the same location on the same day sometimes caused minor bark damage. Pre-coiled wraps of the correct length unraveled in the high humidity of day-time field experiments but remained tightly wrapped in evening trials under less humid conditions. To maintain the coil during storage, we protected wraps with paper, then secured them with a rubber band.
Speakers
AF

Amy Fulcher

University of Tennessee
Co-authors
KM

Karl McKim

The University of Tennessee
LW

Laura Whaley

University of Tennessee
NA
LF

Lauren Fessler

University of Tennessee
NA
LS

Lily Slade

University of Tennessee
NA
Thursday September 26, 2024 12:30pm - 12:40pm HST
South Pacific 2

12:30pm HST

NUTS 2 - Discovery of Early Biomarkers for the Scab Resistance of Pecan Seedlings Using Metabolomic Analysis Combined with Machin
Thursday September 26, 2024 12:30pm - 12:45pm HST
Pecans (Carya illinoinensis (Wangenh.) K. Koch) are globally consumed nuts and an important agricultural commodity in the United States. Scab is a devastating pecan disease, which necessitates the application of numerous fungicide sprays in the growing season of pecans. Even with the control measures, in wet years, scab infection results in great yield loss (over 50% loss in susceptible varieties) and deterioration of nut quality. Although there have been various efforts to alleviate the scab, the development of scab-resistant pecan cultivars is the most effective method to control the disease. However, current methods to assess pecan scab resistance require multiple years of field screening and complicated laboratory (microscopic) techniques. Thus, a simple and reliable method that can rapidly evaluate pecan scab resistance at an early stage of infection is necessary. In this study, metabolomic analysis with machine learning algorithms was utilized to identify early biomarkers for the scab resistance of pecan seedlings. Two pecan seedlings with contrasting scab resistance ('Pawnee' and 'Desirable') were inoculated with water (control), Pa-OK-11 (isolated from 'Pawnee'), and De-Tif-11 (isolated from 'Desirable') for 7 days. 'Desirable' seedlings exhibited resistance to Pa-OK-11, while 'Pawnee' seedlings showed moderate resistance to De-Tif-11. Both cultivars were susceptible to their respective isolates. Leave samples from each seedling were collected at different time points (0, 1, 2, 3, 4, 5, 7 days). For the metabolomics work, liquid chromatography‒mass spectrometry (LC‒MS) was employed to analyze metabolites in samples, which can cover a wide range of primary and secondary metabolisms, including carbon fixation, glycolysis, citric acid cycle, amino acid metabolism, phenylpropanoid, monolignol, and flavonoid biosynthesis. Different machine learning algorithms were compared to find differentially regulated metabolites (biomarkers) between scab-resistant and -susceptible seedling groups. With a combination of machine learning models, we obtained reliable potential biomarkers, e.g., phenolic acids, flavonoids, plant hormones, and their intermediates and precursors, involved in the early stage of scab infection. The selected markers are expected to be used to classify scab resistance levels in pecan seedlings within a week after infection, which may replace the conventional method (phenotype-based mass selection) for pecan breeding selection. In short, this research breaks the bottleneck of resistance screening in pecans and will help facilitate the early selection of scab-resistant pecan cultivars to achieve breeding goals.
Speakers
MJ

Min Jeong Kang

University of Georgia
Co-authors
JS

Joonhyuk Suh

University of Georgia
NA
LW

Lenny Wells

University of Georgia
NA
PC

Patrick Conner

University of Georgia
RP

Ronald Pegg

University of Georgia
NA
Thursday September 26, 2024 12:30pm - 12:45pm HST
Lehua Suite

12:30pm HST

WUM 3 - Irrigation trials examine yield, water productivity, and nitrogen uptake of summer cauliflower
Thursday September 26, 2024 12:30pm - 12:45pm HST
Replicated irrigation trials were performed on cauliflower (Brassica oleracea var. botrytis cv. Symphony) in California’s Salinas Valley during 2018 and 2019. The CropManage online decision-support system was used to guide evapotranspiration-based irrigation scheduling. Overhead sprinklers were used to establish the crop with 60-70 mm of water, followed by surface drip for the remaining crop cycle. A randomized complete block design, with six replications, was used to administer four treatments near 50%, 75%, 100% and 150% of estimated full crop water requirement (T50, T75, T100, T150) during the drip phase. An additional drip treatment at 125% (T125) was added in 2019. Applied water totals across treatments ranged from 199-410 mm in 2018 and 179-369 mm in 2019 (plus 35 mm of precipitation). No significant differences were observed between total curd (head) yields from T100 and T150 in year 1 (> 30 Mg ha-1), although marketable yield from T150 was greater. Total yield of T100 and T125 were significantly greater than T150 during year 2, but marketable yield was similar among T100-T150. No significant difference was observed in fresh or aboveground dry biomass production from T100 and T150. Significant reductions in yields and biomass production were observed in T50 and T75 for both years. T100 and T150 had the highest irrigation water productivity with respect to marketable yield. Nitrogen uptake and fertilizer N recovery were highest in T100 and T150 during 2018, but no significant treatment differences were observed in 2019. These field trials demonstrated that estimating crop evapotranspiration and irrigation requirements of cauliflower through a decision support service such as CropManage can be a reliable tool for irrigation scheduling.
Speakers
MC

Michael Cahn

UC Cooperative Extension
Co-authors
LJ

Lee Johnson

NASA ARC-CREST/California State University Monterey Bay
NA
SB

Sharon Benzen

USDA-ARS
NA
Thursday September 26, 2024 12:30pm - 12:45pm HST
Coral 2

12:35pm HST

GG 2 - Evaluation of watermelon and Citrullus crop wild relatives for resistance to whiteflies and whitefly transmitted viruses
Thursday September 26, 2024 12:35pm - 12:45pm HST
In the Southeastern U.S., cucurbit production is vulnerable to the sweetpotato whitefly Bemisia tabaci and the viruses it transmits. There are limited control methods for the whitefly pest, including mulches, row covers, and spray programs. Unfortunately, none of these practices reduce the whitefly populations to zero, leaving whiteflies behind to transmit viruses. Therefore, host resistance is the best management practice, and the identification of resistant genotypes to whitefly transmitted viruses is a top priority. To aid watermelon breeding for resistance, 21 Citrullus genotypes were evaluated over two field seasons in Tifton, GA in 2022 and 2023. The traits evaluated were viral disease severity (AUDPC), Cucurbit leaf crumple virus (CuLCrV), Cucurbit yellow stunting disorder virus (CYSDV), and Cucurbit chlorotic yellows virus (CCYV) viral loads and in 2022 only, whitefly counts were collected to evaluate whitefly preference. Leaf tissue was collected 5 weeks after transplanting (WAT) in 2022 and 7 WAT in 2023. Total nucleic acids were extracted, and qPCR was performed to determine viral loads. Grif 16444 was the only genotype that had lower adult whitefly counts, indicating non-preference of this genotype. Over the two years there were three consistent genotypes with the statistically lowest AUDPC, two C. mucosospermus (PI 595203 and PI 494528) and one C. ecirrhosus (Grif 16444). In 2022, these three genotypes had significantly lower CuLCrV viral loads than the cultivar checks, however, in 2023 due to low CuLCrV presence there were no significant differences. For CYSDV and CCYV, there were no genotypes with significantly lower viral loads than the cultivar checks in both years. These wild crop relatives provide sources of resistance that can be used by breeders to improve cultivated watermelon.
Speakers
AL

Alexander Luckew

University of Georgia
Thursday September 26, 2024 12:35pm - 12:45pm HST
Nautilus 1

12:35pm HST

PH 2 - Extending the Postharvest Storage of Caladium Tubers to Unlock Late-Season Pot Plant Production Potential in Florida
Thursday September 26, 2024 12:35pm - 12:45pm HST
Florida is home to the largest caladium production in the world, supplying essentially all the global caladium tuber demand. These plants are famous for their vibrant leaf colors and patterns and are asexually propagated through tubers. Following plant development, tubers are harvested and stored for a few months before being forced from March to September for potted plant production and direct landscape planting. During extended postharvest storage, caladium tubers face the risk of severe weight loss, tissue decay, and Fusarium tuber rot. The current practice of storage under ambient conditions with high temperatures and high relative humidity exacerbates weight loss and tuber rot. The challenges of long-term tuber storage make it difficult to produce pot caladium plants for winter holidays, including Thanksgiving, Christmas, and New Year. These challenges also affect the commercialization of tubers in the Southern Hemisphere during the summer. Opening these marketing opportunities can allow growers to extend and increase their production. Additionally, the identification of caladium tubers suitable for late-season production will give Florida growers a competitive advantage. To identify caladium varieties with long-term tuber storage potential and late-season production, 12 varieties were evaluated to target Thanksgiving and Valentine’s Day. No.1-sized tubers were potted in 5-inch containers and grown in a greenhouse. For each variety, 10 tubers were monitored for sprouting and leaf expansion and later evaluated for plant quality using a rating scale from 1 to 5. Eight cultivars were identified as suitable to grow for Thanksgiving, whereas 3 were identified for Valentine’s Day based on long-term storage potential and plant performance. Identification of cultivars will allow growers to expand their commercialization window not only for major holidays but also to supply tuber demand to the Southern Hemisphere.
Speakers
GC

Gasselle Cordova

University of Florida
Co-authors
SS

Steven Sargent

University of Florida
Professor and Extension Postharvest Specialist
ZD

Zhanao Deng

University of Florida
Thursday September 26, 2024 12:35pm - 12:45pm HST
South Pacific 3

12:35pm HST

PNM - Changes Of Fruit Profile And Content Of Carotenoids At Different Nutrient Conditions In Hydroponically Grown Watermelon
Thursday September 26, 2024 12:35pm - 12:45pm HST
Researches on carotenoid content in hydroponically grown watermelon fruits are rarely conducted. In hydroponic system, nutrient condition can be easily monitored and precisely controlled by regulating the concentration of culture solution. To study the changes of fruit profile and content of carotenoids at different nutrient conditions, we cultured watermelon in hydroponic system and changed the electric conductivity (EC) of solution which can represent the condition of nutrient. Forty seedlings were provided by Hagihara Farm company and replanted in the hydroponic system where the electric conductivity of solution equaled 1.2 dS·m-1. Three branches were remained for one plant and each pistil after 20 nodes were pollinated by hands. The nutrient condition was divided 14 days after pollination into 3 groups which were Control (EC = 1.2 dS·m-1), the regime of solution EC = 3.0 dS·m-1 (group 2) and the regime of solution EC = 5.0 dS·m-1 (group 3). Samples were taken every 10 days interval, and the fruit size, weight as well as Brix of flesh were measured on the sampling day. Carotenoid contents were determined by high performance liquid chromatography. Results showed that compared to the control group, fruit size and weight were promoted in group 2 but restrained in group 3. However, group 3 had the highest Brix among three groups. In terms of β-carotene, the higher the concentration of solution was the earlier its promotive and restraining effects showed out. Lycopene was also promoted in the early stage (10-30 days) in group 2 and group 3 but the total amount on 40 days decreased and dropped to near or below the control group.
Speakers
XC

Xiangyu Cui

Meiji University
Co-authors
MO

Masako Osawa

Hagihara Farm Co.Ltd.
NA
ST

Sentaro Tomiyama

Meiji University
NA
TI

Takashi Ikeda

Meiji University
NA
Thursday September 26, 2024 12:35pm - 12:45pm HST
South Pacific 1

12:35pm HST

UG 2 - Irrigation Level Affects Bloom Number and Pollinator Visits in Herbaceous Perennials
Thursday September 26, 2024 12:35pm - 12:45pm HST
Heat and drought in cities can be exacerbated by limitations on water availability for irrigation. While many perennials are drought-tolerant, decreases in bloom number and quality are common. This study has two objectives. First, does bloom number in perennials decrease under limited irrigation. Second, how does this affect the number of pollinator visits. Twenty perennials were randomly planted in twelve beds, arranged in a randomized complete block design, with three beds per block. One plant of each perennial species was planted per bed. Beds within each block were randomly assigned to one of three irrigation levels: ET (evapotranspiration) 0.6, 0.3, and 0.0. Pollinators were counted by standing in front of the plant for 60 seconds and counting each pollinator within the canopy. Bloom number was determined by counting the number of blooms on one quarter of the plant and multiplying by four. Across all species, both bloom number and pollinator visits remained the same across all irrigation levels. However, individual species had very different results. Blue mist flower (Conoclinum coelestinum) had more blooms and pollinator visits in the ET 0.6 treatments (119.4 blooms and 1.3 pollinators per plant) than the ET 0.3 treatments (75.6 blooms and 0.6 pollinators per plant), while fennel (Foeniculum vulgare) had more average blooms per plant in the ET 0.3 (64.1) and ET 0 (54.9) than the ET 0.6 (15.9), though a similar average number of pollinators per plant across all treatments. Interestingly, while blooms and soil water content across all species were not correlated, pollinators and soil water content had a moderate, positive correlation (P=0.01, r=0.49).
Speakers
MC

Madison Coyle

Texas A
NA
Co-authors
Thursday September 26, 2024 12:35pm - 12:45pm HST
Coral 1

12:40pm HST

CHMG/HIH/PUBHORT - Enchanted Garden Youth Program Fosters Appreciation for the Environment and Horticultural Competencies
Thursday September 26, 2024 12:40pm - 12:50pm HST
Enchanted Garden 4-H Day Camp was inspired by our whimsical fairy garden, which is one of the most popular Florida-Friendly demonstration gardens located at UF/IFAS Extension St. Johns County Botanical Garden. The objective of this program is to cultivate appreciation for the natural environment and increase knowledge of sustainable horticultural principles among youth participants. Methods include teaching plant propagation, design and construction of a fairy house, clay saucer design, guided sensory walk, and a scavenger hunt in the garden. Problem solving, critical thinking skills, and teamwork were encouraged throughout this 2 day, 6 hour camp for youth ages 9 to 12. Integrative, experiential, and reinforcement methods of teaching were used to meet the various learning styles. Of the 18 youth participants in 2022 and 2023, 100% reported increased gardening knowledge; 89% increased appreciation for the natural environment; 83% learned how to transplant a plant; 100% increased construction and design skills; and 100% intend to share information learned with others. Additionally, 9 fairy houses were constructed for display in the garden, and each participant took home their new planters to hone their horticultural skills. Enchanted Garden Day Camp was successful in cultivating appreciation for the natural environment and increasing knowledge of horticultural principles among youth participants.
Speakers
TF

Terra Freeman

Urban and Commercial Horticulture Extension Agent, University of Florida
Thursday September 26, 2024 12:40pm - 12:50pm HST
Kahili

12:40pm HST

VCM 3 - Effect Of Selenium Fertilization on Beta-carotene Accumulation in Hydroponically Grown Two cress Varieties
Thursday September 26, 2024 12:40pm - 12:50pm HST
EFFECT OF SELENIUM FERTILIZATION ON BETA-CAROTENE ACCUMULATION IN HYDROPONICALLY GROWN TWO CRESS VARIETIES. A.O. Adeyeye*; T. Nzaramyimana, Ph.D.; A. Kofi. College of Agriculture, Community, and the Sciences, Kentucky State University, Frankfort, KY 40601. Advanced plant cultivation techniques such as hydroponic vegetable planting, coupled with targeted soil micronutrient fertilization, exemplify sustainable agriculture's innovative approach to maximizing crop yields, enhancing nutritional quality, and minimizing environmental impact. This study will investigate the effect of selenium fertilization on the accumulation of beta-carotene in two varieties of hydroponically grown watercress. Hydroponic cultivation offers a controlled environment for plant growth, allowing precise manipulation of nutrient levels to optimize desired outcomes. Selenium, an essential micronutrient for both plants and animals, has been shown to influence the synthesis of secondary metabolites in plants, including carotenoids such as beta-carotene, which are important antioxidants and precursors of vitamin A. In this innovative idea, the experiment will be conducted using two cress varieties, (watercress) and (Upland cress), subjected to different levels of selenium fertilization. Selenium treatments will be applied according to a randomized experimental design, with each variety divided into multiple treatment groups receiving varying concentrations of selenium fertilizer. The hydroponic system provided consistent environmental conditions, including nutrient solution composition, pH, temperature, and light intensity, throughout the experiment. The beta-carotene content in watercress leaves will be quantified using High-performance Liquid chromatography (HPLC)analysis which is a technique used in analytical chemistry to separate, identify, and quantify components in mixtures and this allows for accurate measurement of carotenoid levels. Statistical analysis of the data will reveal significant differences in beta-carotene accumulation between selenium-treated and control groups within each watercress variety. Moreover, variations in beta-carotene accumulation will be observed between the two watercress varieties in response to selenium fertilization, indicating potential genotype-specific responses. Overall, the results will demonstrate that selenium fertilization influences beta-carotene accumulation in hydroponically grown watercress, with implications for agricultural practices and human nutrition. Understanding the interactions between selenium supplementation and carotenoid synthesis in watercress can inform strategies to enhance the nutritional quality of crops and promote sustainable agricultural production systems. Keywords; Selenium fertilization, Beta-carotene, Hydroponic, Watercress varieties, Agricultural sustainability, Crop yields, Environmental impact, Spectrophotometric analysis,
Speakers
AA

Adekunle Adeyeye

Kentucky State University, Frankfort, KY
Co-authors
AK

Alex Kofi

Kentucky State University
Graduate Research Assistant
TN

THEONESTE NZARAMYIMANA

Kentucky State University
Thursday September 26, 2024 12:40pm - 12:50pm HST
South Pacific 4

12:40pm HST

WCPM 2 - Factors Affecting Spray Coverage on Red Maple Trunks from an Air-Assisted Sprayer
Thursday September 26, 2024 12:40pm - 12:50pm HST
Trunk-boring pests are a significant threat to nursery crops. Despite the prominence of air-assisted sprayers, little research has been published about their coverage of tree trunks. We assessed spray characteristics of a Jacto A400/850 sprayer with the objective of determining the lowest spray rate that provided at or near 100% trunk coverage. Water sensitive paper (WSP) was wrapped around the trunks at two heights in an external row and the middle row of a 3-row block of red maples (Acer rubrum) to assess coverage. Assessments included 15 trials with application rates from 65 to 244 GPA at 1.5 and 2.5 mph tractor speeds. Travel Speed: Spraying at 108 GPA and 112 GPA achieved ≥95% coverage when traveling 1.5 mph with windspeeds less than 1.5 mph. Spraying 112 GPA at 1.5 mph provided 96% coverage on wraps at both heights despite a maximum (unsustained) windspeed of 3.9 mph. Increasing the travel speed to 2.5 mph reduced the spray rate to 68 GPA and coverage to 79%. Spraying 244 GPA when traveling 1.5 mph provided 95% coverage. Increasing the travel speed to 2.5 mph decreased the rate to 146 GPA, and yielded coverage of 97%. Spraying 146-224 GPA with 1.0 mph average windspeed or less yielded ≥95% coverage in all four trials. Wind Speed: When traveling 1.5 mph and spraying 108 GPA with an average windspeed of 1.3 mph, 96% coverage was achieved. Coverage was reduced to 88% when the average windspeed increased to 2.5 mph. Stakes: Trees were secured using 1-inch stakes installed 3 inches from the western face of each trunk. The western face of wraps at 9 of 12 locations had coverage equal to or greater than that of the total wrap in three trials with less than 1.3 mph average windspeed. Row: In 10 trials, there was ≤2.5% difference in coverage between external and middle rows. However, in 5 trials the middle row had greater coverage by at least 6%. Spraying 109-112 GPA can provide near complete trunk coverage under low wind speeds. Higher spray rates can overcome high wind and travel speed, but are undesirable given the potential for drift and waste. Neither presence of a stake nor middle row position equates to worse coverage. Trees in the middle row may benefit from being equidistant from the sprayer as it travels down both driveways. These results provide a framework for future trunk coverage tests utilizing variable-rate technology.
Speakers
AF

Amy Fulcher

University of Tennessee
Co-authors
BL

Benjamin Lockwood

University of Tennessee
NA
CF

Cody Fust

Auburn University
NA
HZ

Heping Zhu

USDA-ARS
NA
KM

Karl McKim

The University of Tennessee
LW

Laura Whaley

University of Tennessee
NA
LS

Lily Slade

University of Tennessee
NA
Thursday September 26, 2024 12:40pm - 12:50pm HST
South Pacific 2

12:45pm HST

GG 2 - Development of Specialty Pumpkin Cultivars with Potential to be Released for Organic and Conventional Resilient Cropping
Thursday September 26, 2024 12:45pm - 12:55pm HST
Specialty pumpkins, such as the tropical pumpkin or “calabaza” (Cucurbita moschata Duchesne), are widely grown and consumed in Puerto Rico, ranking second among the most important vegetables on the island. This crop is also increasingly becoming a lucrative emerging market in the United States, particularly in communities with a high density of households of Latino/Hispanic and Caribbean heritage. Yield, fruit quality, and disease resistance of 21 genotypes were evaluated under conventional and certified organic management conditions in Puerto Rico at the University of Puerto Rico Lajas Research Station from January to May 2022, and from November 2022 to March 2023. The genotypes were evaluated using a randomized complete block design with three replications. The number of marketable fruits, total fruits per plot, yield (kg ha-1), and incidence of whiteflies, among other variables, were recorded. Overall, the number of fruits per plot and marketable fruits ranged from 2 and 12, while the yield reached 9,229 kg ha-1 to 65,707 kg ha-1. Under organic certified management, the highest yield was obtained by UFTP42 with 46,567 kg ha-1, while UFTP4 obtained the lowest yield with 5,110 kg ha-1. Under conventional conditions, the UFTP34, UFTP80, and ‘Soler’ lines obtained the highest performance, with 66,677; 63,974, and 75,971 kg ha-1, respectively. On the other hand, the genotypes UFTP4, UFTP10, UFTP22, and UFTP46 obtained lower yields with 9,229; 10,881; 17,635, and 15,408 kg ha-1, respectively. Verde Luz, showed the lowest incidence of whiteflies (< 10%), under both management conditions, while the remaining genotypes showed no significantdifferences between them. In summary, UFTP34, UFTP44, UFTP45, and UFTP80 could be released as prospective cultivars for the southern area of Puerto Rico and could be used as parents for breeding purposes under organic and conventional cropping systems.
Speakers
AL

Angela Linares Ramirez

University of Puerto Rico
Co-authors
GM

Geoffrey Meru

University of Florida
NA
JR

Jorge Ruiz Menjivar

University of Florida
MG

Miguel Garcia Carrucini

University of Puerto Rico - SEA
NA
Thursday September 26, 2024 12:45pm - 12:55pm HST
Nautilus 1

12:45pm HST

PH 2 - Analysis of Oxidative Decreases in Hop (Humulus lupulus L.) Bitter Acids Produced Postharvest
Thursday September 26, 2024 12:45pm - 12:55pm HST
Nearing maturity, female hop plants develop inflorescences called hop cones. Inside of a mature hop cone is the lupulin gland where glandular trichomes are present. Within the lupulin gland, the glandular trichomes secrete alpha acids (α), and beta acids (β). Hop bitter acids are extremely sensitive to photolysis and oxidation reactions causing the degradation of α-acids and β-acids which negatively affect their use in beer, and the beer brewing industry accounts for 98% of world use of hops (Fandino et al., 2015). Determining hop storage index (HSI) is a way to measure the amount of α and β-acids lost during postharvest handling. HSI is a ratio determined by measuring the spectrophotometric UV absorption of hop extract at 275nm for oxidative compounds, and 325nm for bitter acids. Bitter acids and any oxidative decreases were determined in eight cultivars of hops (‘Cascade’, ‘Chinook’, ‘Comet’, ‘Mount Rainier’, ‘Newport’, ‘Tahoma’, ‘Willamette’, ‘Zeus’) produced at the Cimarron Valley Research Station in Perkins, Oklahoma. Mature hop cones were hand harvested at 80% moisture and dried at ambient temperature to 8-10% moisture using a centrifugal fan. Hops were stored no longer than six months frozen under nitrogen in vacuum sealed bags until analysis. Hop bitter acids were extracted using toluene and UV absorbance was measured at 355, 325, and 275nm using a spectrophotometer. Based on the HSI, hops were assigned a quality score of good (0.4). Seven of the eight cultivars of hops were of good quality (‘Cascade’, 0.20; ‘Chinook’, 0.19; ‘Comet’, 0.17; ‘Mount Rainier’, 0.12; ‘Newport’, 0.23; ‘Tahoma’, 0.18; ‘Willamette’, 0.22). ‘Zeus’ hops were of questionable quality (0.31) but contained a slightly higher moisture content at storage (11%) than the other cultivars (7-10%), which could have negatively affected hop storage quality. Understanding sources of oxidative stresses to hop bitter acids during postharvest handling is valuable information for determining and maintaining hop quality.
Speakers
KS

katie stenmark

OKLAHOMA STATE UNIVERSITY
Crop Science PhD Student Department of Horticulture and Landscape Architecture Oklahoma State University
Co-authors
CF

Charles Fontanier

OKLAHOMA STATE UNIVERSITY
NA
NM

NIELS MANESS

OKLAHOMA STATE UNIVERSITY
NA
Thursday September 26, 2024 12:45pm - 12:55pm HST
South Pacific 3

12:45pm HST

PNM - Phosphorus Fertilizer Application Strategies to Improve Phosphorus Availability and Utilization in Potatoes.
Thursday September 26, 2024 12:45pm - 12:55pm HST
Phosphorus (P) is a poorly soluble plant nutrient. Therefore, P uptake by the potato crop is primarily through root interception and short distance diffusion. This limits the percentage of soil supplying P to potato roots. Placement of P fertilizer is a management variable that can influence P uptake and P use efficiency, thereby improving tuber yield and quality. Recent studies conducted at Colorado State University’s San Luis Valley Research Center, USA, has shown that blending orthophosphate fertilizers with 10-34-0 reduces required P fertilizer cost and improves P use efficiency, as well as increase potato tuber yield and quality, compared to using 10-34-0 as sole source of P fertilizer. Information on placement method of blended P fertilizers for maximum use efficiency and tuber performance has not been documented. Studies were conducted at Colorado State University’s San Luis Valley Research Center, USA, with the objective of evaluating the effect of blended liquid P fertilizer placement method on Russet potato performance in the field. Three orthophosphate fertilizers each blended with 10-34-0 were evaluated under three placement methods (banding, in-furrow, and banding in-furrow application). Banding of blended liquid P fertilizers increased medium size (4-10 oz) tuber yield by 22%, compared to in-furrow application. In-furrow application of blended liquid P fertilizers increased production of premium size (> 6 oz and > 10 oz) tuber yield by 8 and 49%, respectively, compared to banding application. Results from this study suggest that appropriate liquid P fertilizer placement method can enhance sustainable potato production.
Speakers
SE

Samuel Essah

Colorado State University
Thursday September 26, 2024 12:45pm - 12:55pm HST
South Pacific 1

12:45pm HST

UG 2 - Strawberry Response to Compost Versus Inorganic Nitrogen
Thursday September 26, 2024 12:45pm - 12:55pm HST
Plant nitrogen use efficiency (NUE) is important in reducing fertilizer costs and mitigating negative impacts on agriculture and the environment. The goal of this research was to differentiate various strawberry cultivars based on their growth on compost versus inorganic nitrogen sources. The hypothesis posits that different strawberry cultivars display varying effects on the soil and plant microbiome. Given the variability in cultivars and their effects on the soil and plant microbiome, it is possible that different cultivars may influence the soil differently. Moreover, plants play a pivotal role in the development of microbiomes, subsequently supporting plant growth. For instance, plants exude amino acids from their roots to foster their beneficial microbiome. This hypothesis was tested by growing 7 cultivars of strawberries for six weeks in a mixture of peat moss and turface with and without added compost and seven replicates. Four of the replicates were used for destructive sampling at the end and three for the microbiome work. The plants were watered daily with a complete soluble fertilizer with and without added nitrogen. Leachate was collected daily and the nitrogen content (loss of nitrogen) determined. Relative growth rate and tissue N uptake was determined for each cultivar at the end of the experiment. To study the microbiome, leaf stamps on agar plates were conducted, enabling the cultivation and analysis of both bacterial and fungal communities associated with the strawberry leaves. This method provided direct insights into the microbial diversity and density present on the plant surfaces. The results of this research revealed that all cultivars grew better on soluble fertilizer than compost but some strawberry cultivars grew better on compost than others. Moreover, the strawberries developed a distinctive leaf microbiome when grown on compost, and variations specific to each cultivar were pronounced. Differential cultivar response to compost and soluble fertilizer supports the hypothesis that different cultivars influence the soil and hence nutrient uptake differently, demonstrating the importance of plant selection for sustainable agriculture and environmental protection. Further research is needed to determine the exact mechanisms.
Speakers
KP

Kauai Paule

University of Hawaii at Manoa
Co-authors
ED

Elizabeth De La Torre

University of Illinois Urbana-Champaign
NA
Thursday September 26, 2024 12:45pm - 12:55pm HST
Coral 1

12:45pm HST

NUTS 2 - Developmental Transcriptomics of Pecan Fruit in ‘Mahan’ and ‘Tiny Tim’
Thursday September 26, 2024 12:45pm - 1:00pm HST
Pecan (Carya illinoinensis) is a nut crop native to the United States and Mexico which is becoming an increasingly important crop globally. Juglandaceous nuts are uniquely high in antioxidants among nuts and a conversion equivalent derived from studies in mice indicates that consumption of 22-38 pecans per day may reverse metabolic disorder in an individual weighing 132 pounds, implying a role in a healthy diet. Despite this importance, relatively little is known about the molecular basis of pecan nut ontogeny compared to other nut crops, leading to difficulties in understanding the physiological issues which plague growers. Susceptibility to various biotic and abiotic disorders including pecan scab, vivipary, water split, and shuck decline are dependent upon the stage of development the pecan nut is in. To better understand the molecular basis and timing of pecan nut development, developmental time-course RNA-Seq was carried out on nuts collected from cultivars ‘Mahan’ (a large nut bearing pecan from Mississippi) and ‘Tiny Tim’ (a small nut bearing native pecan from Missouri) approximately biweekly through the growing season of 2022. Using this data, genes were grouped together into distinct developmental phases, connecting transcriptional changes to the already well-characterized ontogenic stages of pecan nut development.
Speakers Co-authors
WC

Warren Chatwin

USDA ARS Southern Plains Agricultural Research Center
NA
Thursday September 26, 2024 12:45pm - 1:00pm HST
Lehua Suite

12:45pm HST

WUM 3 - Growth Morphology as Indicators of Salt Water Tolerance in Watermelon Cultivars
Thursday September 26, 2024 12:45pm - 1:00pm HST
Saltwater intrusion into coastal areas is a major problem that reduces acreage under vegetable production. Cultivating salt-tolerant varieties is one of the approaches to overcome this problem. The long-term goal of this project is to screen and identify salt-tolerant watermelon germplasm. We assessed the impact of salinity stress from natural brackish water collected in Charleston, South Carolina (32o47’38” N and 80o3’25” W), on the growth morphology of four watermelon cultivars to identify one discriminatory concentration to be used for evaluating hundreds of watermelon accessions available in USDA-ARS Germplasm Resources Information Network. Watermelon plants were hydroponically grown in a Nutrient Film Technique (NFT) system at various EC levels (natural brackish water diluted with de-ionized water to generate 5.5, 10, 12, 14, and 19 dS/m and control, 0 dS/m) and plant growth and shoot morphology were monitored. All cultivars failed to withstand salinity stress at 19 dS/m. Surprisingly watermelon cultivars tolerated fairly high levels of salinity (5.5-14 dS/m ⁓3,530 - 8,960 ppm salt concentration) with inhibited growth. Increasing EC levels correlated with decreased growth parameters such as plant height, leaf number, and shoot fresh and dry weight. Chlorophyll content and electrolyte leakage values increased with higher brackish water concentrations, peaking at 14 dS/m. These values were notably elevated, with chlorophyll content and electrolyte leakage being 5 and 2 times higher than the control, respectively. Cultivar Sugar Baby had significantly greater shoot length, chlorophyll content, and electrolyte leakage compared to other cultivars (Crimson Sweet, Charleston Grey, and Black Diamond). The other growth parameters were similar across all cultivars. Further research to identify an optimal EC between 14 and 19 dS/m for use in large-scale evaluation of germplasm accessions will be needed.
Speakers
AS

AZEEZAHMED SHAIK

Clemson University
Co-authors
Thursday September 26, 2024 12:45pm - 1:00pm HST
Coral 2

12:50pm HST

VCM 3 - Effect Of Levels Of Magnesium Fertilization On The Carotenoid Accumulation Among Three Kale Cultivars Grown Hydroponically.
Thursday September 26, 2024 12:50pm - 1:00pm HST
Phytonutrients in fruits and vegetables are crucial in promoting human health and preventing various diseases. Among these are carotenoids that are found abundantly in green leafy vegetables like kale, which have garnered significant attention due to their numerous health benefits, including antioxidant and anti-inflammatory properties. Despite kale’s reputation as a nutritional powerhouse, little research has focused on the effect of magnesium fertilization on carotenoid production and accumulation in this vegetable. This study aims to address this gap by investigating the impact of different rates of magnesium fertilization on the carotenoid contents and elemental nutrient levels of three hydroponically grown kale cultivars. The Darkibor, Mamba, and Red Russian kales would be grown hydroponically using Hoagland solution in a greenhouse. Different magnesium rates at 0 mgL-1, 12.3 mgL-1, 24.6 mgL-1 and 59.2 mgL-1 would be used. Carotenoid contents and levels in the three kale varieties will be analyzed using High-performance Liquid Chromatography. Additionally, an Agilent 7500ce inductively coupled plasma-mass spectroscopy (ICP-MS) system will be used to measure their elementary nutrient levels. Data would be analyzed using the PROC GLM analysis of variance (ANOVA) and regression analysis procedure of the SAS v9.1 software package. At the end of the experiment, it is expected that increased rates of magnesium fertilization will lead to a significant increase in the accumulation of carotenoid and elemental nutrient levels in each kale cultivar. Understanding how magnesium fertilization influences carotenoid accumulation and other nutrient levels in kale could improve nutritional quality, thereby reducing reliance on dietary supplements to address nutrient deficiencies. Keywords: Phytonutrients, Magnesium, Carotenoids, Kale, Antioxidants
Speakers
avatar for Alex Kofi

Alex Kofi

Graduate Research Assistance, Kentucky State University
Graduate Research AssistantResearch interest: Controlled Environment Agriculture especially in hydroponics
Co-authors
AA

Adekunle Adeyeye

Kentucky State University, Frankfort, KY
TN

THEONESTE NZARAMYIMANA

Kentucky State University
Thursday September 26, 2024 12:50pm - 1:00pm HST
South Pacific 4

12:50pm HST

WCPM 2 - Rice Hull Use in Container Production; Economics and Efficacy
Thursday September 26, 2024 12:50pm - 1:00pm HST
Weed control in woody ornamental container production is one of the most expensive inputs in production. Preemergent herbicides, mulches and hand labor are all methods of delaying, impeding, or removing weeds that will negatively impact the growth and aesthetics of the produced container plant. One method gaining popularity in Central Florida to reduce weed competition is the use of rice hulls (RH) as a mulch. Effective mulches will reduce the amount of weed competition plants face. Rice hulls are a byproduct from the rice industry and deemed a disposed waste. RH are applied by hand in a layer of about 0.5 to 1 inch deep and dry out in a relatively quick manner. Growers anticipate that RH reduce the costs of weed competition and hand labor from weeding operations. This research investigated the economic cost of RH and benefit of RH mulch in terms of weed growth reduction.
Speakers
SS

Shawn Steed

University of Florida
Thursday September 26, 2024 12:50pm - 1:00pm HST
South Pacific 2

12:55pm HST

GG 2 - SSR Marker Development and Fine Mapping of Linkage Group 2 Eastern Filbert Blight Resistance from ‘Georgian OSU 759.010’
Thursday September 26, 2024 12:55pm - 1:05pm HST
Anisogramma anomala, causal agent of Eastern Filbert Blight (EFB), is endemic to eastern North America and was accidentally introduced to the Pacific Northwest hazelnut (Corylus avellana) growing regions around 1960. A single gene conferring resistance was identified in the pollinizer ‘Gasaway’ by the OSU Hazelnut Breeding Program, and deployed across the Willamette Valley in the majority of cultivars released since 2008. In preparation for a mutation or second accidental new introduction, research has focused on discovering, mapping, and developing useful molecular markers for new sources of resistance. In October 2023, a new isolate of A. anomala was detected in a grower’s orchard in Woodburn, OR, growing on the previously resistant ‘Jefferson’. The results of this study focus on linkage group 2 resistance (LG2), conveyed by ‘Georgian OSU 759.010’. Using two populations from a cross between ‘OSU 1477.047’ with Georgian resistance and ‘Sacajawea’ with quantitative resistance, n=272 recombinant offspring were identified using existing SSR markers. Marker development resulted in 40 new SSR markers covering an 8.5Mbp region, and a linkage map of the resistance region was constructed. Characterization of the 40 new SSR markers is in progress.
Speakers
BH

Brianna Heilsnis

Oregon State University
Co-authors
JS

Jacob Snelling

Oregon State University
NA
SM

Shawn Mehlenbacher

Oregon State University
Thursday September 26, 2024 12:55pm - 1:05pm HST
Nautilus 1

12:55pm HST

PH 2 - The Use of Desiccants for Proper Moisture Preservation in Green Coffee During Storage and Transportation
Thursday September 26, 2024 12:55pm - 1:05pm HST
Prolonged storage and long-distance transportation of green coffee beans exposes them to undesirable fluctuations in temperature (T) and relative humidity (r.h.), which can change the physical (wet-basis moisture content (MCwb), water activity (Aw), and color) and sensory characteristics of the coffee. High humidity also supports mold growth, decay, and microbial activities. Thus, the objective of this study was to evaluate the efficacy of commercially available desiccants for preserving the moisture content of green coffee between 10 and 12% MCwb, when stored in either hermetic packages and/or jute sacks, and to assess the corresponding impact on sensory quality. A conventional coffee storage and transportation period from Brazil to Italy with a duration of 42 days was mimicked in environmental chambers. Treatments in a 3 × 3 factorial design consisting of three packaging materials (GrainPro SuperGrain bag, GrainPro TranSafeliner, and/or jute sacks) and desiccants (Drying Beads®, CaCl2, or no desiccants) were evaluated. Additionally, four different mass ratios of green coffee to desiccant ranging from 50 to 300 – g coffee per g desiccant were also evaluated. The MCwb, Aw, and color of all samples were measured approximately weekly over 42 days. In comparison to the control (no desiccant, and only jute sacks), we observed a statistically significant impact for all tested desiccants and hermetic packages for maintaining the proper MCwb, Aw, and color. No significant difference was observed for the different desiccant masses tested when they were placed inside the hermetic packaging, but the desiccants were ineffective without the hermetic packaging. Triangle test and descriptive sensory evaluation yielded no significant differences between the use of hermetic packages with or without desiccants.
Speakers
LA

Laudia Anokye Bempah

UC DAVIS
Laudia Anokye-Bempah is a Ph.D. student in the Biological Systems Engineering Program at the University of California Davis. Her research focuses on the kinetics of coffee roasting, with the ultimate goal of designing a “Coffee Roasting Control Chart” that will be used to produce... Read More →
Thursday September 26, 2024 12:55pm - 1:05pm HST
South Pacific 3

12:55pm HST

PNM - Nitrate Leaching in Processing Tomato Production Subjected to Deficit Irrigation and On-Demand Nitrogen Fertilization
Thursday September 26, 2024 12:55pm - 1:05pm HST
The information presented in this poster represents the first-year findings of an ongoing two-year study to assess the efficacy of two nitrogen (N) fertilization and irrigation approaches on tomato yield and quality, and the Nitrate (NO3) Leaching Index (NLI) defined as the ratio of the amount of NO3 in 60-120 cm of soil to the amount in 0-120 cm. Water and N use efficiency (WUE and NUE) were determined for processing tomatoes (Solanum lycopersicum) grown on a Handford Sandy Loam soil, with a pH of 6.7, in the San Joaquin Valley (SJV), California, USA. The experiment was a split-plot design with three replications of irrigation rates (I) as the main factor based on evapotranspiration (ET) scheduling amounts of 74% and 100% of crop evapotranspiration (ETc) and two fertilizer (F) application methods as the subplot factor. The Growers Practice (GP) was seven equal applications of CAN-17 for a total of 201 kg N/ha (180 lbs N/ac) over the growing season, whereas the Soil Nitrate Quick Test (SNQT) approach was to apply 17kg N/ha (15lbs N/ac) whenever the NO3 test strip value was less than 20 ppm. A total of 36 beds with a width of 130 cm x length of 2,700 cm were planted so that each subplot comprised three beds, with the two outer beds used as buffer rows. There were no significant differences in the total yield of all tomatoes (reds, breakers, and green) harvested as a function of either the irrigation (p= 0.79) or fertilizer rates (p=0.12). However, for the fully matured marketable red tomatoes, fertilizer practice had a significant effect (p=0.02), with the GP yielding approximately 30% more tomatoes than the plots subjected to SNQT. There was no interaction effect of F x I on the yield of these red tomatoes. With respect to sugar content, I (p
Speakers
avatar for Dave Goorahoo

Dave Goorahoo

Professor, California State University, Fresno
Co-authors
AG

Aldo Garcia

California State University, Fresno
NA
FC

Florence Cassel

California State University, Fresno
JB

John Bushoven

California State University, Fresno
NA
Thursday September 26, 2024 12:55pm - 1:05pm HST
South Pacific 1

12:55pm HST

UG 2 - SOFT Science: Cultivating Sustainable Horticulture Leaders Through the Student Organic Farm Training Program.
Thursday September 26, 2024 12:55pm - 1:05pm HST
The Student Organic Farm Training (SOFT) program, established in 2007, is a student-run organic mini farm that serves as a co-curricular, hands-on learning environment for several classes at the University of Hawaii. The program's three-fold mission is to 1) highlight the role of ecological processes in organic food production through an interactive learning garden, 2) promote community health and sustainability via local food production, and 3) cultivate skills in entrepreneurship, management, and leadership among student participants in relation to agriculture. Key objectives include facilitating peer-to-peer knowledge sharing, increasing student access to affordable local organic produce, and improving student proficiency in regenerative management of horticultural systems. Specific initiatives include developing a themed educational garden, hosting workshops led by faculty/students, providing internships and volunteer opportunities, conducting on-site research, distributing produce to underserved populations, coordinating volunteer workdays, and community outreach through off-site volunteering and attending events/markets. In partnership with Noelani Public Elementary School, SOFT has engaged over 400 students in hands-on STEM learning. Through "soup" and "pizza" themed gardens, these first graders explored topics such as photosynthesis, soil, nutrition, and food safety, fostering a lifelong love for gardening and healthy eating. SOFT’s long-term goals include further integration with university curricula, transitioning to a self-sustaining operation, and expanding the program's scope to incorporate diverse horticultural systems.
Speakers
AM

Alana Marie Barros

University of Hawai’i at Manoa
NA
Co-authors
EC

Eric Collier

University of Hawai’i at Manoa
NA
MP

Megdelena Perkins

University of Hawai’i at Manoa
NA
TR

Theodore Radovich

University of Hawai’i at Mānoa
Thursday September 26, 2024 12:55pm - 1:05pm HST
Coral 1

12:59pm HST

Plasticulture (PLAST)
Thursday September 26, 2024 12:59pm - 1:50pm HST
Conserving Soil Moisture in High Tunnels to Maintain Soil Health - Claire Barnhart
Impact of Microplastic Amended Soils on Growth and Physiology of Lettuce Crop - Vanaja Kankarla
Introducing A New Biobased, Biodegradable Mulch: Lignocellulosic Film - Aidan Williams
Performance and suitability of biodegradable plastic mulches for winter strawberry production in Florida: Mulch deterioration, microenvironment modification, and growth and yield responses - Hadi Ghasemi
Plastic and Biodegradable Mulches in Agroecosystem: A Comparative Life Cycle Assessment Perspective to Environmental Impact and Economic Considerations - Oluwatunmise Dada
Moderator
VK

Vanaja Kankarla

Florida Gulf Coast University
Thursday September 26, 2024 12:59pm - 1:50pm HST
Kahili

1:00pm HST

PLAST - Conserving Soil Moisture in High Tunnels to Maintain Soil Health
Thursday September 26, 2024 1:00pm - 1:10pm HST
The use of polyethylene tarps is becoming popular for urban and small-scale vegetable farmers to manage weeds through occultation. Similar tarps can also be used as plastic mulch in high tunnels during the growing season. However, little is known about how this will affect crop productivity and soil moisture retention. Trials were conducted in 2022 and 2023 to determine the effect of white silage tarp, black silage tarp, paper mulch and black landscape fabric as compared to bare soil for lettuce and tomato grown in high tunnels. Two lettuce varieties (red and green) were planted in a split-plot randomized complete block design in the fall and tomatoes were grown during the summer. Soil samples were used in combination with soil moisture meter readings to determine gravimetric and volumetric soil moisture content throughout the season. Tomato trials were conducted in six high tunnels and six open-field plots. For both crops, harvesting occurred to monitor total, marketable, and non-marketable yield. According to a one-way ANOVA test, there was not a significant treatment effect in the 2022 lettuce trial. However, the 2023 lettuce trial revealed that white and fabric treatments were the most effective at conserving soil moisture. On average, there was 2.6% higher soil moisture in plots with white silage tarp and black landscape fabric as compared to the bare ground plots. In the high tunnel tomato trial, the bare plots had significantly lower volumetric and gravimetric soil moisture levels (P
Speakers
CB

Claire Barnhart

Kansas State University
Co-authors
CR

Cary Rivard

Kansas State University
EP

Eleni Pliakoni

Kansas State University
JC

Jeremy Cowan

Kansas State University
NA
PT

Peter Tomlinson

Kansas State University
NA
TJ

Tricia Jenkins

Kansas State University
Thursday September 26, 2024 1:00pm - 1:10pm HST
Kahili

1:00pm HST

VCM 3 - Red And Blue LED Lighting Effects On Hydroponically Grown 'Koba' Green Onion
Thursday September 26, 2024 1:00pm - 1:10pm HST
Food safety, environmental impact, and efficient energy usage are growing concerns in horticultural production systems. In Hawaii, 'Koba' and local strains of green onion can be planted year round. The use of artificial lighting in green onion production could be a solution to help address the above concerns. The objective of this study was to compare the effects of red and blue LED lighting on the growth of 'Koba' green onion plants in a noncirculating hydroponic system. 'Koba' green onion (Allium fistulosum) seeds were germinated in Oasis® cubes under T5 high output fluorescent lighting in the lab. Seedlings were then transferred to 5.1-cm net pots, which were placed in 1.9-liter containers containing a hydroponic nutrient solution of Hydro-Gardens' Chem-Gro lettuce formula 8-15-36 hydroponic fertilizer with added calcium nitrate (19% Ca and 15.5% N) and magnesium sulfate (9.8% Mg and 12.9% SO4). Half of the seedlings were grown under red LED lighting (82 µmol/m2/s, 12-h photoperiod) and half under blue LED lighting (82 µmol/m2/s, 12-h photoperiod). Data was collected at the end of the experiment. At the end of the study, there were significant differences in plant height, number of leaves per plant, stem diameter, total leaf length per plant, leaf dry weight per plant, and root dry weight per plant. For all these variables, red LED lighting resulted in greater values than those for blue LED lighting. In conclusion, different LED lighting could be used to supply artificial lighting for 'Koba' green onion plants. Red LED lighting enhanced the growth of 'Koba' green onions.
Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
Co-authors
BN

Brylin Nelson

Univ of Hawaii at Manoa
NA
Thursday September 26, 2024 1:00pm - 1:10pm HST
South Pacific 4

1:00pm HST

WCPM 2 - Organic and Synthetic Herbicides for Controlling Liverwort Growth in Containerized Ornamental Production
Thursday September 26, 2024 1:00pm - 1:10pm HST
Liverwort (Marchantia polymorpha L.) is a nonvascular, chlorophyll-containing, primitive, spore-bearing bryophyte. It is one of the major weed problems in container nurseries and greenhouse operations as it competes with the ornamental plant for resources within the container. Application of herbicides is a major component of any weed control program in ornamental production systems. There are limited herbicides labeled for liverwort control in greenhouse container production. A greenhouse experiment was conducted to evaluate the effect of various organic and synthetic herbicides on controlling liverwort growth. The herbicides were applied to nursery containers filled with standard substrate and amended with controlled release fertilizer for assessing the post-emergent liverwort control. Organic products namely Avenger, Scythe and WeedPharm were applied at 1X and 2X rates. Synthetic herbicides – Glyphosate, 2,4-D and Indaziflam were applied at 1X, 2X and 3X rates. Control set without any herbicide application was included as well. Percent of substrate surface covered by liverwort thalli was visually estimated bi-weekly until 16 weeks after first treatment. Fresh biomass of the thalli in each pot were also recorded at the end of the experiment. The experiment had six replications per treatment, and they were arranged in a randomized complete block design. For both the synthetic and organic herbicides, there was significant interaction between the type and rate of herbicide applied. The herbicide treatments were significantly different amongst each other and from the control. Out of various organic herbicides applied, all the herbicide treatments were able to limit liverwort coverage under 30% as compared to control (98%). WeedPharm and Scythe application at 2X and Avenger application at 1X rates recorded minimum liverwort fresh biomass. In the synthetic herbicide treatments, Indaziflam at 2X and 3X rates had minimal liverwort coverage and fresh biomass at the end of the experiment. Hence, these organic and synthetic herbicides can be a promising component for an integrated liverwort control program in containerized ornamental production.
Speakers
MS

Manjot Sidhu

Michigan State University
Co-authors
DS

Debalina Saha

Michigan State University
Thursday September 26, 2024 1:00pm - 1:10pm HST
South Pacific 2

1:00pm HST

NUTS 2 - Pistachio Orchard Productivity Enhancement Through Molecular Marker Preselection
Thursday September 26, 2024 1:00pm - 1:15pm HST
There is significant variation in tree size, which determines productivity, in commercial pistachio orchards planted with UCB-1 seedling rootstocks. It has been unclear to extent to which this is due to genetic differences or environmental variation. Nurseries have tried to tackle this problem by rogueing young seedlings before they are planted in orchards. However, our data previously demonstrated that performance in the first year is a poor predictor of later tree size. Genotyping by sequencing data from experimental and commercial orchards and genome wide association studies (GWAS), combined with our chromosome-scale, high quality, genome assemblies for the parental Pistacia atlantica and P. integerrima trees resulted in two highly informative molecular markers for vigor. Based on the genomic sequence information, we developed an inexpensive, quick, and easy qPCR protocol for single nucleotide polymorphism (SNP) marker analysis. We were able to predict the improved size distribution that extant orchards would have had if this marker had been used to rogue seedlings prior to planting in the orchards. We want this marker to make it available for nurseries to rogue out trees which would exhibit low vigor and productivity later in an orchard.
Speakers
EJ

Ewelina Jacygrad

University of California Davis
Co-authors
DG

Deborah Golino

University of California Davis
NA
JE

John E. Preece

University of California, Davis
NA
KC

Keri Cavanaugh

University of California, Davis
NA
RM

Richard Michelmore

University of California Davis
NA
RH

Robert H. Beede

UCCE Kings County, CA
NA
Thursday September 26, 2024 1:00pm - 1:15pm HST
Lehua Suite

1:00pm HST

WUM 3 - Assessment of Salinity Tolerance in Cucumber Cultivars Using NFT System
Thursday September 26, 2024 1:00pm - 1:15pm HST
Increasing salinity levels pose significant challenges to coastal vegetable cultivation, particularly impacting salt-sensitive crops like cucumber, leading to reduced growth, development, yield, and quality. This study assessed the responses of six commercial cucumber cultivars to different salinity levels. Cucumber plants were grown in a hoop house hydroponically using various dilutions of brackish water in a Nutrient Film Technique (NFT) system at EC levels 3, 6, and 12 dS/m, along with adequate controls (0 dS/m). Increasing salinity levels caused a significant decline in plant growth parameters (shoot length, biomass, leaf number). Overall a 59% reduction in shoot length and 52% decrease in dry biomass was observed at 12 dS/m compared to control. The cultivar, Stripped Armenian had significantly greater shoot length (163 cm) and dry biomass (59 g), compared to the others (Diva, Katrina, Lemon, H-19 Little Leaf, and Suyolong) by 52-207% and 126-409%, respectively. Additionally, Stripped Armenians dry weight exceeded the control by 120%, 115%, and 25% in 3, 6, and 12 dS/m treatments, respectively. Gaseous exchange parameters measured with Licor 6850 (photosynthetic rate, stomatal conductance, transpiration rate, and intercellular CO2 concentration) declined significantly with increasing salinity at vegetative and reproductive stages. The photosynthetic rate and stomatal conductance showed reductions of 15-17% and 13-50%, at salinity levels of 3 dS/m, 6 dS/m, and 12 dS/m, compared to the control treatment respectively. Similar reductions were also observed at the reproductive stage. Stripped Armenian consistently exhibited higher photosynthetic rate (4-27%), stomatal conductance (7-75%), and transpiration rate (6-56%) compared to other cultivars at vegetative and reproductive stages. In conclusion, Stripped Armenian demonstrated substantial tolerance to 12 dS/m salinity compared to other cultivars and may prove useful in saline environments, however further research is needed.
Speakers
AS

AZEEZAHMED SHAIK

Clemson University
Co-authors
Thursday September 26, 2024 1:00pm - 1:15pm HST
Coral 2

1:05pm HST

GG 2 - Enhancing the Fruit Set of NJ BP1-1 Beach Plum (Prunus maritima)
Thursday September 26, 2024 1:05pm - 1:15pm HST
Wild plum, Prunus maritima, has a native habitat that ranges from coastal Virginia to Nova Scotia and is well known to be associated with beach communities with sandy soils. Recent trials by Rutgers, New Jersey Agricultural Experiment Station suggests beach plum has the potential to be grown throughout the state where higher clay content, fertile soils contribute to increased vegetative growth leading to a dense bush habit. Crop potential is abundant due to high natural bloom density. However fruit set has been challenging under traditional commercial growing systems, partly due to self-incompatibility. BP1-1 Jersey Jems cultivar was bred and selected by the Rutgers University Plant Breeding program for its high yield, large size and superior flavor in costal locations where there are diverse beach plum pollen clouds. In order to establish clonal orchards of this cultivar, a pollen parent must be identified. In this study, a total of 7 controlled test crosses were made in triplicate on BP 1-1. Fruit yields were collected from BP1-1 and top yielding crosses were noted. The purpose of this study is to find compatible pollen parents, ensuring quality and uniform yield to base future pollen parent recommendations in New Jersey commercial tree fruit orchards.
Speakers
MM

Megan Muehlbauer

Rutgers University
Co-authors
PN

Peter Nitzsche

Rutgers NJAES Cooperative Extension
NA
RM

Rebecca Magorn

Rutgers Cooperative Extension
NA
Thursday September 26, 2024 1:05pm - 1:15pm HST
Nautilus 1

1:05pm HST

PH 2 - Transcriptome Analysis Revealed that Metabolites and Hormone Signaling Pathway Differently Respond to Non-chilling and C
Thursday September 26, 2024 1:05pm - 1:15pm HST
Cucumber (Cucumis sativus L.) fruit is sensitive to chilling temperatures during storage, and the physiological mechanism of chilling injury (CI) is not well known. Understanding the chilling response in cucumber fruit is necessary to delay CI and extend the storage duration during postharvest. In this study, our goal was to identify CI symptoms and investigate key factors influencing on the chilling response in cucumber fruit (C. sativus var. ‘Hangang’). To assess the severity of CI symptoms, cucumber fruits were stored at low temperatures of both 13 °C (non-chilling response) and 2 °C (chilling response) for 9 d and exposed to 20 °C. As a result, various CI symptoms of discoloration, shirankage, water-soaking and necrosis area appeared on a cucumber fruit peel stored at 2 °C, resulting in loss of its marketability from 6 d. To clear the cellular mechanism of CI symptoms, transcriptome analysis was conducted in cucumber fruit stored for 1 d (early response) and 6 d (late response). The results suggested that phytohormone synthesis and signalling played major roles in chilling responses. To reveal the main phytohormone involved in the chilling response, eight phytohormones were quantified in cucumber fruit peel using LC-MS/MS. Among them, ABA was not sufficiently accumulated at 2 °C compared to 13 °C during the early response, and SA levels gradually increased by persisting chilling stress. Through these results, major phytohormone synthesis and signalling genes were selected by RT-qPCR. For further understanding of CI, targeted metabolite analysis was conducted, and amino acids such as isoleucine, serine, valine, threonine, and sucrose were identified as significant metabolites for acclimating to chilling temperatures. These findings help to elucidate the hormonal mechanisms involved in chilling response as well as the complex interplay of various molecular components involved in chilling response of cucumber fruit during storage.
Speakers
YS

Yujin Sim

Seoul national university
Co-authors
EJ

Eun Jin Lee

Seoul National University
KM

Kyeonglim Min

Seoul National University
Thursday September 26, 2024 1:05pm - 1:15pm HST
South Pacific 3

1:05pm HST

PNM - Greenhouse Nitrogen application rate optimization for optimal bamboo (Dendrocalamus asper) growth and productivity in Florida
Thursday September 26, 2024 1:05pm - 1:15pm HST
Bamboo, a giant tropical and temperate region grass, is used for food, timber, furniture, building and construction material, and paper making, among others. With the US being the world's number one importer of bamboo shoots, many growers are venturing into bamboo production with little or no knowledge of the best management practices. There is no reliable literature conducted in Florida about the crop. Therefore, this study was conducted to develop site-specific nitrogen (N) requirements for young bamboo plants in a controlled environment. This study was done in a greenhouse at UF/IFAS Citrus REC in Lake Alfred. One-year-old bamboo plants were transplanted into 37.85 L pots and treated with varying rates of N (0,112,224, and 336 kg N ha-1). Growth, photosynthetic rate, and tissue composition were measured biweekly for five months. Initial and final soil analyses were done. The results demonstrated that higher rates of N (up to a certain amount, i.e. 224 kg N ha-1) increased growth rate, number of culms, and dry matter accumulation. Analysis of Variance (ANOVA) test and regression analysis were conducted for the response variables in R software. Chlorophyll content and culm diameter were comparable. It was concluded that 200 kg/ha N was optimal for young bamboo plants since it demonstrated the peak growth rate, number of culms, and dry matter compared to the rest of the treatments. Key words: Dendrocalamus asper, nitrogen fertilization, best management practices
Speakers
CJ

CYRUS JANUARIE

UNIVERSITY OF FLORIDA
Co-authors
DK

Davie Kadyampakeni

University of Florida
NA
Thursday September 26, 2024 1:05pm - 1:15pm HST
South Pacific 1

1:05pm HST

UG 2 - Phenological Modeling of Pollenizing Crabapple Cultivars (Malus spp.) and Commercial Apple Cultivars (Malus X domestica
Thursday September 26, 2024 1:05pm - 1:15pm HST
Commercial apple cultivars require a pollinizer for cross-pollination to ensure fruit-set yields when planted in contiguous blocks found in modern apple orchards. Pollinizers must have compatible viable diploid pollen and have bloom overlap with the variety grown in the orchard block. Climate change can influence the viability of a pollenizer cultivar by shifting the bloom times of the pollinizers and the commercial apple cultivar, depleting the source of pollen for that block, and decreasing yield potential. 4 commercially available pollenizing crabapple cultivars (Indian Summer, Mt. Blanc™, Mt. Evereste™, Snow Drift) were replicated 5 times in completely randomized design. Pollinizers were analyzed weekly for developmental stages from silver tip to petal fall. 7 apple cultivars were also analyzed for comparison. The stage progression data for each pollenizer cultivar was modeled using growing degrees days base 6.6°C. These models were used to compare the stage progression and bloom dates of the pollenizer cultivars, and compared to the production apple cultivars to assess bloom overlap and determine pollinizer feasibility. All 4 crabapples began to bloom earlier than the scion cultivars leading to little bloom overlap. Indian Summer was the first crabapple to bloom on 3/28 with cumulative growing degree days (GDD) 166.4. The latest to bloom was Mt. Blanc on 4/13 with cumulative GDD 250.1. The commercial cultivars did not begin to bloom until 4/6 with cumulative GDD 199.6 through 4/13 with cumulative GDD 250.1. While the first commercial cultivar to bloom was Gold Rush and most at full bloom around 4/13, at which time all but Mt. Blanc crabapples were past bloom. Results suggest most pollinizer cultivars have poor bloom overlap with commercial cultivars in Kentucky, with Mt. Blanc offering the best, though limited overlap. Furthermore, the crabapple cultivars are seemingly responding to environmental cues such as chilling and GDD accumulation differently to leave dormancy and progress through bloom at a more rapid rate. These early results suggest that the use of crabapple cultivars as pollinizers and their overlap with commercial apple cultivars could be an area of concern as climate change brings earlier springs in major apple producing regions.
Speakers
MW

Miranda Woodcock

University of Kentucky
Co-authors
BA

Brent Arnoldussen

University of Kentucky
NA
Thursday September 26, 2024 1:05pm - 1:15pm HST
Coral 1

1:10pm HST

PLAST - Impact of Microplastic Amended Soils on Growth and Physiology of Lettuce Crop
Thursday September 26, 2024 1:10pm - 1:20pm HST
Plastic pollution is a global concern due to its adverse effects on ecological systems. Plastic disposal and degradation release small fragments known as microplastics (MP) that can accumulate, infiltrate, and travel through soil, air, water, plants, and the environment. Studies indicate the omnipresence of MPs in soils and show their potential to influence seed germination, plant growth, and development. To investigate the effects of microplastics on seed germination, two replicated germination experiments were conducted under controlled conditions in germination chambers, SciBrite TM LED lighting at their optimum germination temperature of alternating 22/35°C day/night for a 14-hour photoperiod for 30 days at Florida Gulf Coast University. Seeds of Lettuce (Lactuca sativa), a widely cultivated horticultural crop were sown in petri plates (100 x 15 mm) containing four different soil amendments with microplastics PET (polyethylene terephthalate) fiber-filled microplastics (v/v) at 0.5%, 1%, 1.5%, and 2% concentrations and sizes < 125 µm, 126-250 µm, 251-375 µm, and 376-500 µm. Seeds were considered germinated with the protrusion of the radicle from the embryo. Germinated seeds were tossed away and calculated for Germination % (GP) and Mean Germination Time (MGT). Our preliminary results showed microplastics at lower concentrations of 0.5% and 1.0% decreased GP and increased MGT compared to higher concentrations of MPs. Small MP sizes showed negligible impact on the GP and MGTs. Future research will involve conducting pot experiments in a hoop house at the Southwest Florida Research and Extension Center (SWFREC), UF/IFAS, Immokalee to assess the impact of microplastics on plant growth, development, plant physiology and regulation. Data collection will include measurements of plant height, leaf chlorophyll content, photosynthetic gas exchange, leaf area Index (LAI), fresh and dry plant biomass (g), visual rating, and spectral signatures of healthy versus stressed plants at various intervals of crop growth stages. Keywords: PET microplastics, germination %, mean germination time, physiology, spectral signatures
Speakers
VK

Vanaja Kankarla

Florida Gulf Coast University
Thursday September 26, 2024 1:10pm - 1:20pm HST
Kahili

1:10pm HST

VCM 3- Plant Health Aerial Mapping Integration In Precision Agriculture Systems
Thursday September 26, 2024 1:10pm - 1:20pm HST
Aerial multispectral imaging is a great tool for early detection of plant health stresses. There is a variety of sensing hardware with even more options for data analysis ranging in their ease of use and computing power requirements. These tools have been used very successfully in research settings such as breeding trials, nutrient management evaluations, and pesticide efficacy trials. These technologies have tremendous potential benefits if utilized in commercial production systems. While some agronomic crop producers have been using some of these technologies to some extent, there have been various barriers to adoption in specialty crop production. Data collection, analysis, and computing power limitations are some of the primary challenges. However, we find that there is a serious limitation in integration and data output compatibilities from the analysis side to plugging in precision ag equipment. In this project, we examine multiple systems and platforms from data collections to creating decision maps used in field equipment. This project is conducted in partnership with specialty crop growers and aerial service providers. We are in the process of streamlining the process of data collection, analysis, and creation of decision maps, to optimize the use of ground based or aerial fertility and pesticide precision applicators.
Speakers
WE

Wael Elwakil

University of Florida
Thursday September 26, 2024 1:10pm - 1:20pm HST
South Pacific 4

1:10pm HST

WCPM 2 - Impact of Changing Climate on Weed Control in Ornamental Crop Production: A Potential Research Area
Thursday September 26, 2024 1:10pm - 1:20pm HST
The ornamental crop industry is a billion-dollar industry in the United States. Controlling weeds is a big challenge, as they can compete with ornamentals for soil, nutrients, water, light, and space by affecting the desired quality of ornamental crops like leaf and flower quality and color as well as proper growth. Weeds can also harbor insects, pests, diseases, and pathogens resulting in further reduction of market value. Due to greater genetic diversity and physiological plasticity, weeds are more likely to be able to adapt to a changing environment or climate. Increased atmospheric carbon dioxide (CO2) level can cause fertilization effect in C3 plants resulting in higher growth rates. Conversely, C4 plants are less likely to exhibit increased growth responses to elevated CO2 levels, as carbon dioxide fixation becomes saturated for them at around 360 ppm. So, ornamentals could gain a competitive advantage over many of the major weed species under elevated CO2, as many of the world’s ornamental crop species are C3 plants and many of the major weed species are C4 plants. But in reality, the scenario is different because other factors such as changes in herbicide efficacy and the ability of weed species to out compete ornamental species may come into play and limit this advantage. Plants that are grown in CO2-enriched environments often develop high concentrations of starch in leaves and greater total leaf area and biomass which can cause a dilution effect on herbicides. Additionally, C3 plants have been shown to have decreased stomatal conductance and increased leaf thickness in elevated CO2 which may also limit foliar uptake of herbicides. Environmental factors such as temperature, precipitation and relative humidity influence the efficacy of herbicides. There are studies that have reported decreased herbicide efficacy for control of annual and perennial weeds in elevated CO2 environments in agronomic crops. But limited information is available on how change in climate can affect herbicide efficacies in ornamental production. Hence, the objectives of this research proposal are: Evaluating increased temperature and CO2 levels on growth and reproduction of two different types of container-grown ornamentals; Determining effects of temperature and CO2 rise on preemergence herbicide performances for controlling C3 and C4 weed species; Determining effects of temperature and CO2 rise on postemergence herbicide performances for controlling C3 and C4 weed species; Assessing adaptive features of weed species with the change in environmental factors.
Speakers
SS

Supti Saha Mou

Michigan State Univ.
Co-authors
DS

Debalina Saha

Michigan State University
Thursday September 26, 2024 1:10pm - 1:20pm HST
South Pacific 2

1:15pm HST

GG 2 - The wonderful world of worms: Microbiota of rabbit manure vermicompost at different maturities
Thursday September 26, 2024 1:15pm - 1:25pm HST
Vermicompost, derived from the processing of organic waste by earthworms, is a beneficial soil amendment known to improve plant and soil health due to the presence of beneficial microorganisms. Vermicompost microbiome can vary radically depending on the starting substrate, environmental conditions, and earthworm species, making it important to characterize the microbial community over time under a variety of vermicomposting conditions. To characterize the microbial community of vermicompost produced from rabbit manure, four samples were collected from vermicomposting bins (Avery Islands, LA) for Nanopore long-read sequencing: one unprocessed manure samples, and samples which had been composting for 1-, 6-, and 12-months. About 135Gb of sequence data with a median quality of Q19 was produced. Relative taxonomic abundance of the microbial community was assessed using Kraken2 and Braken. Manure samples differed in microbiome composition, but were both much less diverse than vermicomposted samples, which had much greater bacterial diversity and were rich in nitrogen-fixing bacteria such as Mesorhizobium and Bradyrhizobium. 1-month old vermicompost more closely resembled 12-month old vermicompost than unprocessed manure, suggesting that a majority of the benefits of vermicomposting are realized within a relatively short period of time.
Speakers Co-authors
Thursday September 26, 2024 1:15pm - 1:25pm HST
Nautilus 1

1:15pm HST

PH 2 - Fresh Weight of Indoor-Grown Lettuce under Different Postharvest Storage Practices
Thursday September 26, 2024 1:15pm - 1:25pm HST
Two-thirds of food waste occurs once the product has reached the consumer. In an effort to extend the shelf-life of produce, a common practice of hydroponic lettuce growers, particularly those who use controlled environment production systems such as greenhouses or indoor growing facilities, is to harvest the lettuce without removing the root tissue. However, the postharvest quality of this “living lettuce” has not been a focus of academic research, and its effect on the shelf-life of the produce is unknown. In this study, lettuce harvested from an indoor production facility that utilizes a vertical hydroponic setup was subjected to four postharvest treatments. Treatments included harvesting the complete lettuce plant or removing the roots after harvesting and storing the harvested produce either inside or outside of a plastic clamshell. Lettuce was stored for 28 days at 4 °C and 85% relative humidity. Fresh weight of the lettuce heads was assessed for 18 days post-harvest. As days in storage increased, the fresh weight of lettuce decreased by 0.37 grams per day. The rate of lettuce fresh weight decrease was the same across postharvest treatments, but the lettuce with roots intact stored inside a plastic clamshell had a higher fresh weight across all measured time points. A better understanding of the relationship between fresh lettuce weight and storage time under different postharvest conditions can help to increase the shelf life of the stored produce and reduce food waste.
Speakers
CB

Caroline Blanchard

Research Associate II, Auburn University
Co-authors
CR

Camila Rodrigues

Auburn University
NA
DW

Daniel Wells

Auburn University
NA
MT

Marlee Trandel Hayse

Auburn University
TR

Tanzeel Rehman

Auburn University
NA
Thursday September 26, 2024 1:15pm - 1:25pm HST
South Pacific 3

1:15pm HST

PNM - Determining Adequate Nutrient Application Rates for Water Spinach (Ipomoea aquatica) Production in Deep Water Culture
Thursday September 26, 2024 1:15pm - 1:25pm HST
Water Spinach (Ipomoea aquatica) is a novel crop within the U.S. that is widely grown throughout southeast Asia. Although considered a noxious weed by USDA, interest from ethnic communities has led to the restricted permittance of cultivation within Georgia, USA. In order to determine nutrient requirements for hydroponic production of water spinach, a study was conducted using a deep-water culture in a greenhouse located in Watkinsville, Georgia, USA in the summer of 2023. Two selections of water spinach were grown in plastic containers filled either a ¼ or ½ strength Hoagland’s solution arranged in a randomized complete block design with four replications of each selection by nutrient solution combination. Initially, 15 plants of each selection were placed into the tubs. Beginning at 21 days after transplanting, two plants were removed from each tub for determination of biomass and nutrient concentrations. Additional plants were removed at 10-day intervals until a final harvest at 61 days after planting. The trial was then repeated. Results indicated that biomass (root and shoot) and nutrient removal within foliar tissues were significantly greater in the ½ strength solution compared to the ¼ strength solution. Total nutrient accumulation for most macronutrients exhibited a quadratic response, increasing until 51 days after planting and then plateauing. Plants grown in the ½ strength and ¼ strength Hoagland’s solution accumulated similar concentrations of foliar macronutrients though due to differences in biomass accumulation, total nutrient removal was significantly different between the two nutrient solutions. At harvest (day 61), ½ strength plants had an average potassium (K) concentration of 5.24% (dry weight), while those grown in the ¼-strength Hoagland’s solution averaged 4.48% K on a dry weight basis. However, due to significant differences in biomass production, K nutrient removal rates were more than twice as much in the plants grown in the ½ strength Hoagland’s solution compared to those grown in the ¼ strength solution. Our results suggest that although water spinach may grow in river systems in its native environments, that growth benefits from additional levels of fertilizer nutrients when cultivated in greenhouse systems and that a ½ strength Hoagland’s solution should be an appropriate baseline to develop recommendations for hydroponic nutrient solutions for greenhouse production of water spinach.
Speakers
SB

Shelbie Bohensky

University of Georgia
NA
Co-authors
TC

Timothy Coolong

University of Georgia
Thursday September 26, 2024 1:15pm - 1:25pm HST
South Pacific 1

1:15pm HST

UG 2 - Determining Sap Yield, Sugar Content, and Mineral Composition of European White Birch Trees
Thursday September 26, 2024 1:15pm - 1:25pm HST
The demand for locally sourced agricultural products in the United States is growing, with consumers increasingly seeking unique items and willing to pay premium prices for them. Currently, birch products such as birch sap and birch syrup are primarily produced in Alaska and the Eastern United States. However, there may be an opportunity for birch tree owners in the western United States to enter this market with their own local birch products. European white birch (Betula pendula), a common landscaping tree in the cooler northern regions of Utah, presents a potential resource for this industry. Despite the prevalence of these trees, there is a lack of research on the feasibility of tapping them for sap in the Intermountain West. This study aims to address this gap by evaluating the sap yield, sugar content, and mineral composition of European white birch trees in Northern Utah. In the spring of 2024, birch trees in Logan, North Logan, Hyde Park, and Smithfield, UT, were tapped using plastic sap buckets. Daily sap yields were recorded for each tree from 16 March to 11 April 2024, and sap samples were analyzed for sugar and mineral content. This preliminary research provides crucial data for assessing the viability of a birch tapping industry in Northern Utah. While further research is necessary for a comprehensive evaluation, this project lays the groundwork for understanding the potential of tapping European white birch trees in this region.
Speakers
AP

Abby Porter

Utah State University
Co-authors
XD

Xin Dai

Utah State University
YS

Youping Sun

Utah State University
Thursday September 26, 2024 1:15pm - 1:25pm HST
Coral 1

1:15pm HST

NUTS 2 - Fatal Flaws of Experimental Almond Varieties and Selections
Thursday September 26, 2024 1:15pm - 1:30pm HST
The California almond industry has funded multiple, multi-site almond variety evaluation trials over the last several decades. These field trials have previously evaluated many of the varieties that are now the most widely planted in California. Although, field evaluation trials are helpful for revealing which varieties are promising, they are, perhaps, most valuable to the industry for revealing which varieties/selection have serious flaws and should not be planted by growers. Thirty named cultivars and numbered breeder selections were planted in three replicated commercial orchards across California’s Central Valley in 2014. Of these 30, as of April 2024, one numbered selection Y116-161-99 from the USDA has been commercially released as ‘Yorizane’. However, nine of the 30 varieties/selections were dropped from further evaluation in the trial in 2022 for a variety of reasons: low yield (five), lack of interest by the breeder (two), extremely early bloom timing (one), and poor harvestability (one). Of the 21 still being evaluated in 2024, many have one of these major flaws, or additional flaws, that will likely prevent commercial adoption, including a high percentage of double kernels, susceptibility to bacterial blast (Pseudomonas syringae pv. syringae), Botryosphaeria canker disease susceptibility, hull rot susceptibility, and a high percentage of kernel creases or twins, just to name some of the additional flaws. Even if a variety/selection has high yield, good kernel quality, and none of these major flaws documented after ten years of evaluation (e.g. Y117-91-03 from USDA), further observation in the UC trial sites or in the orchards of early adopters may reveal important flaws that prevent sustained and widespread variety adoption. This long-term challenge is why some believe it takes decades to prove a new scion variety. The wide diversity of potentially fatal flaws underscores the need for cultivar evaluation to take place by a third-party like UC Cooperative Extension in long-term replicated trials to reduce substantial financial risk to the grower to the greatest extent possible. Keywords: Prunus dulcis, almond, variety evaluation, breeding, nut crop
Speakers
LM

Luke Milliron

University of California Agriculture Natural Resources
Co-authors
PG

Phoebe Gordon

University of California Cooperative Extension
RD

Roger Duncan

UC Cooperative Extension
NA
Thursday September 26, 2024 1:15pm - 1:30pm HST
Lehua Suite

1:15pm HST

WUM 3 - Influence Of Deficit Irrigation And Biochar Application On Soil Water Depletion, Roots Distribution, And Water Use Effic
Thursday September 26, 2024 1:15pm - 1:30pm HST
A rapid decline in water table of the Ogallala aquifer necessitates water conservation farming practices in Texas High Plains (THP). Deficit irrigation (DI) and biochar amendment strategies are widely adopted to sustain agriculture in semi-arid regions like THP. Although these practices are studied individually, research involving the combined effect of these factors is lacking, especially in THP. The goal of this study was to investigate the effect of DI and biochar application on soil water depletion, root distribution, and water use efficiency of cucumber in West Texas. A two-year field study was conducted in a split-plot design with irrigation levels as the main plots: I1[100% crop evapotranspiration (ETc) replacement before mid-season (EBM))-100% ETc replacement after mid-season (EAM), I2 (80% ETc EBM- 60% ETc EAM), I3 (60% ETc EBM - 80% ETc EAM), I4 (40% ETc EBM-40% ETc EAM)] and biochar rates [ 0 t/ha,15 t/ha, and 20 t/ha] as sub-plots with four replications. Results showed that I4 had the largest and I1 had the least soil water depletion, and the differences in water depletion among irrigation levels were significant up to 1-m soil depth. Root length density (RLD) and root surface area density (RSAD) were significantly higher in I1 followed by I2 and I3, and these parameters were the least in I4. Water Use Efficiency (WUE) showed I2 being the most water productive DI treatment with an average increase of 5% compared to I1. Biochar didn't influence water depletion, RLD, and WUE but significantly increased RSAD compared to non-amended plots. Thus, deficit irrigation level I2 can be a potential alternative irrigation to full irrigation for enhancing water productivity of cucumber in the THP. More pronounced biochar effects could be expected in long term studies.
Speakers
SS

Sukhbir Singh

Texas Tech University
NA
Co-authors
AK

Arjun Kafle

Texas Tech University
CS

Catherine Simpson

Texas Tech University
NA
GR

Glen Ritchie

Texas Tech University
NA
MS

Manpreet Singh

University of California Agriculture and Natural Resources
NA
PB

Preetaman Bajwa

Texas Tech University
NA
SD

Sanjit Deb

Texas Tech University
NA
Thursday September 26, 2024 1:15pm - 1:30pm HST
Coral 2

1:20pm HST

PLAST - Introducing A New Biobased, Biodegradable Mulch: Lignocellulosic Film
Thursday September 26, 2024 1:20pm - 1:30pm HST
Lignocellulosic film is a new biobased, soil-biodegradable mulch option for horticultural cropping systems, created as an environmentally friendly substitute to polyethylene (PE) and non-biobased soil-biodegradable mulch. PE mulch is widely known as a large contributor to agricultural plastic waste since it is made from non-biodegradable polymers. To provide a more sustainable alternative to PE mulch, commercially available soil-biodegradable mulches are on the market, as they are designed to biodegrade in soils upon tillage. One of the main limitations of the currently available soil-biodegradable mulches is that they are not allowed in certified organic agriculture, because they are not made with 100% biobased feedstocks. Lignocellulosic film is made with fully biobased, renewable feedstocks, such as wood chips, giving it the potential to address this problem. Lignocellulose is plant biomass consisting of the components of plant cell walls, which include lignin, cellulose, and hemicellulose. Wood chips are ground up, and through a facile dissolution/dispersion and regeneration process, lignocellulosic film is created. When preparing black lignocellulosic films, biochar may be added as a colorant. Within a recyclable solvent, the ground wood and biochar mixture are dissolved and/or dispersed. Once the mixture is cast into a sheet, it undergoes a washing and drying procedure, which results in an entirely biobased film. Information regarding the material properties of lignocellulosic film relative to other agricultural mulches will be presented along with future directions of research to improve end-of-life outcomes of agricultural mulch film in horticultural systems.
Speakers
AW

Aidan Williams

Washington State University
Co-authors
HD

Haishun Du

University of Wisconsin-Madison
NA
LD

Lisa DeVetter

Washington State University
NA
TL

Teng Li

University of Maryland
NA
XP

Xuejun Pan

University of Wisconsin-Madison
NA
YY

Yuan Yao

Yale University
NA
Thursday September 26, 2024 1:20pm - 1:30pm HST
Kahili

1:20pm HST

VCM 3 - Evaluation of Vegetable Soybean Adaptations to South Florida’s Tropical Climate
Thursday September 26, 2024 1:20pm - 1:30pm HST
Vegetable soybean, also known as edamame, is a specialty crop harvested at an immature stage and consumed as pods. It has become increasingly popular in the United States due to its high nutritional value and good taste. Currently, most edamame consumed in the U.S. is imported as a frozen product. States such as Arkansas and Kentucky have started to grow this crop locally on a small scale to meet the high demand. South Florida, known for producing fresh vegetables sold nationwide, especially in the winter and spring markets, also has a highly diverse and growing ethnic population with significant local market potential. These factors make growers in South Florida highly interested in cultivating edamame to meet the demand in both national and local markets. Sixteen commercial edamame varieties were selected and assessed for differences in phenotypic performance, including emergence, yield, plant height, plant width, 10-pod weight, and pod size, to evaluate their production potential in South Florida. Varieties showed significant effects on most traits studied. Emergence rates ranged from 0 to 85%, and fresh pod yield ranged from 4.41 to 14.34 t/ha among all 16 varieties. Varieties like Goo, Karikachi #3, and Midori Giant, despite having moderate emergence rates, produced higher fresh pod yields due to their larger plants, resulting in bigger pods. There were variations in average pod length (35.61 – 51.21 mm), width (9 - 14 mm), and thickness (5.46 - 8.74 mm) among the varieties, with Goo standing out significantly in size. Overall, Goo, Karikachi #3, and Midori Giant demonstrated particularly favorable yield and good pod quality, showing potential for commercial edamame production in South Florida. This research highlighted the potential to grow edamame in higher hardness zone, providing foundational knowledge on edamame production in the US.
Speakers
XL

Xiaoying Li

University of Florida, IFAS
Thursday September 26, 2024 1:20pm - 1:30pm HST
South Pacific 4

1:20pm HST

WCPM 2 - Development of “EZA”, a New Pesticide Suitable for Organic Production of Horticultural Crops
Thursday September 26, 2024 1:20pm - 1:30pm HST
Production of economically important horticultural crops in the world, especially in developing countries, is faced with major challenges, including pests, and diseases. As a result, producers rely heavily on excessive use of synthetic pesticides, which often leads to negative impact to the environment, human health, and pesticide resistance. There is a need to develop environmentally friendly products to manage pests and diseases to increase crop yield, quality, and nutrition. Research was conducted in Rwanda to develop “EZA”, a new pesticide acting as an insect repellent, made of essential oils from local invasive plants such as Lantana camara, Tagetes minuta, and wastes of chili pepper and garlic. EZA was tested on tomatoes and mangoes under field conditions to manage several insect pests, including armyworms, fruit flies, thrips, and diseases such as tomato late blight caused by Phytophthora infestans. Results showed that EZA was effective in controlling insect pests, providing control of thrips and tomato late blight at the rate of 90% on 5 tomato plants where applied. Furthermore, tomato yield was increased by 40%. Information from this study demonstrates that EZA could significantly benefit horticultural crop producers, especially smallholder farmers in developing countries such as Rwanda, to effectively manage insect pests and diseases and the increase of crop yield.
Speakers
MU

Merci Uwimbabazi

Kentucky State University
NA
Thursday September 26, 2024 1:20pm - 1:30pm HST
South Pacific 2

1:25pm HST

PH 2 - Modified Hydrocooling and Optimized Postharvest Handling Practices Can Improve the Shelf Life of Water Spinach During Su
Thursday September 26, 2024 1:25pm - 1:35pm HST
In an effort to improve the shelf life of water spinach (Ipomoea aquatica Forsk.) and amaranth (Amaranthus tricolor L.) during summer in humid subtropical regions like northern Taiwan, the study investigated the effectiveness of modified hydrocooling and optimized postharvest handling practices. Most farmers in Taiwan often compromised postharvest vegetable quality due to uneven cooling. The first trial implemented a modified hydrocooling system using a 10-minute 5°C shower with a multi-hole perforated pipe and smaller baskets for precooling to substitute the conventional method. The results showed that the modified hydrocooling improved cooling uniformity and reduced vegetable loss rates. Meanwhile, for some farmers needed to meet the specialized market requirement which extend vegetable shelf life, the second trial conducted optimized postharvest handling practices including storage vegetables at 11°C, consistently clean 10°C water for washing/hydrocooling, and wrapping vegetables in plastic film. These practices revealed significantly decreased the water spinach quality loss for longer duration but less effective for amaranth. Even with the addition of hypochlorous acid in washing/hydrocooling water, the shelf life of amaranth was difficult to extend due to severe pre-harvest leaf disease. In conclusion, the study showed that modified hydrocooling offers benefits for most conventional farmers by reducing vegetable loss rates. On the other hands, for farmers needed to meet the specialized market requirement, optimized postharvest handling practices significantly improves the quality of water spinach in longer shelf life. Also, the research emphasized the importance of disease management in amaranth cultivation for postharvest quality.
Speakers
WS

Wei Shiang Liao

Taoyuan District Agricultural Research and Extension Station, Ministry of Agriculture
Co-authors
AC

Ah Chiou Lee

Taoyuan District Agricultural Research and Extension Station, Ministry of Agriculture
NA
WF

Wing Fu Fung

Taoyuan District Agricultural Research and Extension Station, Ministry of Agriculture
NA
Thursday September 26, 2024 1:25pm - 1:35pm HST
South Pacific 3

1:25pm HST

PNM - The incorporation of black soldier fly larvae to fish feed increased fish and plant growth
Thursday September 26, 2024 1:25pm - 1:35pm HST
The economic success of the aquaponics industry and fish farming is mostly dependent on the use of inexpensive, nutritionally adequate meals. Approximately sixty percent of the economic balance is accounted for by fish feeding. The substitution of insect meal for fish meal appears to offer a promising approach to reducing cost and the environmental impact. The black soldier fly larvae (Hermetia illucens) possess 40–45% proteins and a favorable essential amino acid profile. The objective of this experiment was to investigate the effects of commercial and black soldier fly larvae (BSFL)-based diet on Nile tilapia growth, plant growth, and antioxidant accumulation in crops. The results showed that tilapia fish can grow at a higher rate on BSFL-based meals than on commercial diets. On the other hand, a study revealed that BSFL BSFL-based fish feed waste water significantly stimulated plant growth and antioxidant accumulation in aquaponic systems. This study opens up new possibilities for using BSFL as a substitute for fish meal, which could help to reduce the environmental effect of aquaponic production systems while also contributing to a circular economy.
Speakers
MT

Most Tahera Naznin

Associate Professor of Urban & Indoor Agriculture, University of Nevada, Reno
Co-authors
JN

Jessica Nolan

University of Nevada, Reno
Thursday September 26, 2024 1:25pm - 1:35pm HST
South Pacific 1

1:30pm HST

PLAST - Performance and suitability of biodegradable plastic mulches for winter strawberry production in Florida: Mulch deteriorration, microenvironment modification, and growth and yield responses
Thursday September 26, 2024 1:30pm - 1:40pm HST
Biodegradable plastic mulches (BDMs) have been introduced as an alternative to polyethylene (PE) mulches, which are costly to remove and dispose of. The objective of this study was to evaluate the performance and suitability of biodegradable plastic mulches for winter strawberry production in Florida. We conducted a field experiment using ‘Florida Brilliance’ short-day strawberry in the 2023-2024 winter season in West Central Florida. The experiment consisted of five mulch treatments: black PE mulch (control), black starch-based BDM (Mater-Bi®), black resin-based BDM (Ecovio®), white starch-based BDM (Mater-Bi®), and white resin-based BDM (Ecovio®). Although mulch deterioration was minimal on the bed top, it was more evident on the sides or at the base of the bed, especially for starch-based BDMs. Compared to black PE and BDMs, white BDMs increased light reflection and light interception by the canopy. Consequently, white BDMs recorded lower mulch surface, canopy, and fruit temperatures. White BDMs had 35% and 15% higher early season marketable yield (December–January) than black PE and BDMs, respectively, whereas total marketable yield did not show any significant difference. White BDMs showed significantly higher fruit soluble solids content than all black mulches. These results of suggest that the performance and suitability of biodegradable plastic mulches depend on their colors and compositions.
Speakers
HG

Hadi Ghasemi

PhD Graduate Assistant, University of Florida
Co-authors
LD

Lisa DeVetter

Washington State University
NA
NB

Nathan Boyd

University of Florida
NA
SA

Shinsuke Agehara

University of Florida
Thursday September 26, 2024 1:30pm - 1:40pm HST
Kahili

1:30pm HST

VCM 3- Lettuce Cultivar Trials in a Deep Water Culture (DWC) Hydroponic System
Thursday September 26, 2024 1:30pm - 1:40pm HST
Lettuce (Lactuca sativa L.) is a leafy vegetable in the Asteraceae family and is classified into various types, such as Romaine, Butterhead, Crisphead (Iceberg and Batavian), Latin, Leaf, and Stem. Lettuce propagates by the seeds. The seedling can grow in soil or a hydroponic system in a controlled environment Agriculture (CEA) system. This study was conducted to study the ability of different types of lettuces to grow in a hydroponic system and to assess the effect of light, humidity, and temperature on the yield. The experiment was conducted twice (2023 and 2024) in the Department of Agricultural Science lab at Morehead State University. Four lettuce cultivars, including 'Gustav's Salad' and 'May Queen' as the Butterhead type, 'Ice Queen' as a Crisphead type, and 'Lollo' as the Leaf type, were planted directly on rock wools (Rockwool Starter Plugs) in 2-inch Garden Net Pot in hydroponic containers. The commercial aquarium pumps constantly aerated the nutrient solution. Plants were fertilized with liquid plant food, and the Standard Hydroponic solution controlled the pH. The artificial light was provided by a mix of different lights (µmol/m2/s), including LEC, LED, and Fluorescent, for 16 hours daily under different temperatures (°C) and humidity (%). Biological control products were used for pest and disease control. Harvesting was done after 60 days, and fresh and dried yields of leaves were calculated. The roots were also collected and weighed. Dried leaves and roots were ground and analyzed. The primary results show significant differences among different cultivars.
Thursday September 26, 2024 1:30pm - 1:40pm HST
South Pacific 4

1:30pm HST

WCPM 2 - Impact of Partial Saltwater Agroecosystems on Weed Competition in Watermelon
Thursday September 26, 2024 1:30pm - 1:40pm HST
The issue of soil salinity as a major cause of poor soil health and crop yield loss has been of growing concern as climate change contributes to its effects. The objective of this research was to study the impact of increasingly saline soils on the relationship between grafted watermelons and yellow nutsedge, one of the major weeds in watermelon plasticulture. The seedless watermelon cultivar Melody was grown in a field after being grafted onto the C. maxima hybrid Carnivor and the C. amarus cultivar Carolina Strongback in addition to both a self-grafted and ungrafted control. The field was divided into four rows, which were irrigated with 0, 10%, 20%, and 30% dilutions of sea water for the duration of the experiment. A weed count was performed after one month and three months of irrigation. This demonstrated that salt had a significant effect on the total weed count at high concentrations, however the weeds demonstrated a much greater resistance to salt treatment than the watermelons in this trial. Based on this data, it is possible that salt intrusion events can contribute to increased weed related yield loss in watermelon crops.
Speakers
JB

Joseph Bazzle

Clemson University
Co-authors
BW

Brian Ward

Clemson University
MC

Matthew Cutulle

Clemson University
SB

Sandra Branham

Clemson University
NA
Thursday September 26, 2024 1:30pm - 1:40pm HST
South Pacific 2

1:30pm HST

WUM 3 - Assessing Resource-use Efficiency Affected by Irrigation Management Practices in Processing Onion Production
Thursday September 26, 2024 1:30pm - 1:45pm HST
This study aimed at conducting an impact evaluation of irrigation management practices in processing onion production. A three-year experiment was carried out in 15 commercial processing onion fields under different irrigation methods of furrow, solid-set sprinkler, and subsurface drip. The experimental sites were located in the Imperial Valley, California’s low desert region. All fields were on a 40-inch bed, six plant rows per bed with a spacing of 2.5-in between planting lines. The fields had a variable soil type with predominate soil texture from fine sandy to silty clay loam. Water, nitrogen, and energy used, bulb weights, soil moisture, soil nitrate and salinity, and actual evapotranspiration were measured in each site. A wide range of seasonal irrigation water applied was observed across the experimental sites. Irrigation water applied varied from 3.3 ac-ft/ac in a drip irrigated field to 6.9 ac-ft/ac in a furrow irrigated field. The results demonstrated that utilizing subsurface drip irrigation in processing onions could conserve 0.8 and 2.4 ac-ft/ac water in compared with solid-set sprinkler and furrow irrigation systems, respectively. The water productivity, the ratio of onion bulb weight to water applied, was determined 4.9, 4.3, and 2.7 t/ac-ft for the drip, sprinkler, and furrow irrigated fields, respectively. A greater nitrogen use efficiency was found in the drip irrigated fields compared to the sprinkler (15.2% points) and furrow (62.1% points) irrigated fields. The findings illustrated a higher salt accumulation on the topsoil (0-6 in. depth) in the drip irrigated fields. In other words, drip irrigation could cause salinity impacts in desert processing onions, and therefore, more frequent light irrigation events may be an effective tool to manage salinity. More nitrate leaching was also observed from the topsoil in the sites irrigated by sprinklers. Energy productivity, the ratio of onion bulb weight to fuel consumption, was 48.3% points higher in the drip fields than the sprinkler fields. The results revealed that irrigation practice has a significant impact on resource-use efficiency and environmental issues.
Speakers
AM

Ali Montazar

University Of California Cooperative Extension
Thursday September 26, 2024 1:30pm - 1:45pm HST
Coral 2

1:30pm HST

Learning/Working in an Interdisciplinary Aspect of Food and Agriculture Systems
Thursday September 26, 2024 1:30pm - 2:00pm HST
Traditional disciplines in food and agriculture education are insufficient to fulfill the gaps of knowledge and innovation to solve future challenges. How agriculture and farming have been perceived is very different from what reality needs to be. We will share examples and current jobs available in an integrated farming/food system program in North Carolina to provide skill training, career development, and workforce development opportunities within a private/public collaboration. The integrated approach including production, marketing, finance, risk management, renewable energy, Workload, expectations, and types of tasks will be explained including compensation and other support.
Speakers
KL

Kathleen Liang

Kellogg Distinguished Professor, North Carolina Agricultural and Technical State University
Thursday September 26, 2024 1:30pm - 2:00pm HST
Coral 5

1:35pm HST

PH 2 - Discovery of Biomarkers for Postharvest Pecan Color Stability Using Metabolomics and Machine Learning Algorithms
Thursday September 26, 2024 1:35pm - 1:45pm HST
Nut kernel color is a crucial quality indicator affecting consumers' first impression of the product. In the postharvest stage, nut kernels (e.g., pecans) gradually darken with increasing blue/red colors, which have a negative impact on consumers' preference. While growing evidence suggests that plant phenolics and their derivatives are linked to pecan kernel color, the compounds (biomarkers) responsible for kernel color stability during storage remain elusive. We hypothesized that: (1) the phenotype of pecan color exhibits notable variation among different cultivars during storage; and (2) this variation is attributed to changes in metabolites and their combination effects in the stage of phenolic biosynthetic pathways related to color formation. Here, pathway-based metabolomics with machine learning (ML) algorithms were employed to identify key metabolites of postharvest pecan color stability. Nine pecan cultivars with different color stabilities were selected, and the color of each cultivar was measured over a 6-month storage period (0, 1, 2, 3, and 6 months). Metabolites in phenylpropanoid, flavonoid, and anthocyanin biosynthetic pathways were analyzed in the outer layer of the kernel (testa) using liquid chromatography–mass spectrometry. Different ML models were compared to find relevant biomarkers of pecan color phenotypes. Lasso regression and support vector machine (linear kernel) in conjunction with recursive feature elimination were chosen as the most effective models to select biomarkers that predict the kernel color of pecans. Results revealed twenty marker compounds (flavonoid precursors, flavonoids, anthocyanidins, and anthocyanins) within phenylpropanoid, flavonoid, and anthocyanin biosynthetic pathways, and their roles in pecan color phenotypes during storage. Our findings provide a foundation for future research in the area and will help select genes/proteins for the breeding of pecans with stable and desirable kernel color. The collected information on biomarkers and their effects will also help set up strategies for the quality control of pecans after harvest.
Speakers
MJ

Min Jeong Kang

University of Georgia
Co-authors
JS

Joonhyuk Suh

University of Georgia
NA
LW

Lenny Wells

University of Georgia
NA
PC

Patrick Conner

University of Georgia
RP

Ronald Pegg

University of Georgia
NA
WK

William Kerr

University of Georgia
NA
Thursday September 26, 2024 1:35pm - 1:45pm HST
South Pacific 3

1:40pm HST

PLAST - Plastic and Biodegradable Mulches in Agroecosystem: A Comparative Life Cycle Assessment Perspective to Environmental Impact and Economic Considerations
Thursday September 26, 2024 1:40pm - 1:50pm HST
The rise in the use of agricultural plastic mulch films raises environmental concerns, necessitating sustainable alternatives. Despite acknowledged benefits, the widespread adoption of biodegradable mulch over traditional plastic mulch remains a topic of debate. This review employs a comparative life cycle assessment perspective to explore the interplay between environmental impact and economic considerations associated with the production, use, and end-of-life of plastic and biodegradable mulch films. It also postulates impact mitigation strategies for mulch use in agroecosystem. Overall, biodegradable mulch films demonstrate superior merits in energy use and greenhouse gas emissions, but often contribute more to eutrophication, acidification, and land-use occupation compared to plastic mulch films. Environmental burden was found to vary based on polymer type, life cycle stage, end-of-life strategy, fertilizer application, additive content, film thickness, and climate. The manufacturing stage for both mulch types significantly contributed to greenhouse gas emissions and energy use, while plastic mulch film post-use stage contributed to human toxicity, ecotoxicity, eutrophication, acidification, GHG emissions, and photochemical effects depending on the end-of-life choices and adsorbed waste content. Energy and material recovery options are major strategies to mitigate post-use impacts, with recycling being preferable, albeit with the need to address eutrophication and human toxicity. Both mulch types increase yield, but deposited plastic mulch film residue creates soil health problems. On all fronts, biodegradable mulch films, especially starch-derived films, are more environmentally justifiable replacement for plastic mulch films, but higher production costs hinder widespread adoption. From an alternative perspective, straw mulch is a promising replacement for plastic mulch films in dryland areas due to yield, cost, and GHG reduction advantages. However, prevention of open burning and minimizing N-fertilizer applications to reduce N2O releases must be considered. The choice between plastic and biodegradable mulch films, therefore, requires a holistic assessment considering specific contextual nuances. This review elucidates these intricacies from economic, agronomic, and environmental viewpoints, providing an unbiased decision-making tool for agronomists, farmers, mulch film manufacturers, recyclers, and policymakers.
Speakers
avatar for Oluwatunmise Dada

Oluwatunmise Dada

Graduate Research Assistant, Washington State University
A Ph.D. Candidate.
Co-authors
LY

Liang Yu

Washington State University
NA
TC

Ting Chi

Washington State University
Thursday September 26, 2024 1:40pm - 1:50pm HST
Kahili

1:44pm HST

Viticulture and Small Fruits 4 (VSF 4)
Thursday September 26, 2024 1:44pm - 2:45pm HST
First They’re Sweet, Then They’re Sour: The Impact of Cultivar, Berry Maturity, and Phytohormones on Blueberry Quality Uniformity - Michael Gasdick
Phytohormone and Plant Growth Regulator Use in Blueberry Production – A Review - Daniel Dick
Postharvest Quality of ‘Calypso’ Blueberry After Hand and Machine Harvest - Wei Yang
Preliminary Findings from the Evaluation of New Cranberry Cultivars in Massachusetts - Giverson Mupambi
Moderator
WY

Wei Yang

North Willamette Res
Thursday September 26, 2024 1:44pm - 2:45pm HST
Nautilus 1

1:44pm HST

Growth Chambers and Controlled Environments 6 (CE 6)
Thursday September 26, 2024 1:44pm - 3:30pm HST
Timing Kale Growth for Peak Nutrition and Energy Efficiency in a Vertical, Hydroponic Indoor Container Farm - Skyler Brazel
Effects of Beneficial Bacterial Endophytes on Growth of Lettuce Plants, Transcriptome, and Root Microbiome in Hydroponic Systems - Chuansheng Mei
Soybean Speed Breeding: Optimizing Photoperiod for Maximizing Yield and Minimizing Time - Cristiane da Silva
Energy Modeling and Management to Improve the Sustainability of Indoor Farming - Ying Zhang
Increasing Circularity in Controlled Environment Agriculture using Anaerobic Digester Effluent as an Organic Fertilizer - Ana Martin Ryals
Utilizing Deep Learning for Hydroponic NFT Channel Spacing Optimization - Azlan Zahid
Modeling Evapotranspiration in Greenhouse and Indoor Cutting Propagation - Daniel Crawford
Thursday September 26, 2024 1:44pm - 3:30pm HST
Coral 1

1:44pm HST

Public Horticulture/Hort Industry (PUBHORT/Hort Industry)
Thursday September 26, 2024 1:44pm - 3:45pm HST
Enhancing Public Garden Experiences: Utilizing QR Codes and Videos for Plant Identification and Education - Bailey Singleton
Educational Signage in a Community Garden can Assist in Volunteer Learning - Jonah Trevino
Marigolds - An Overlooked Cut Flower Alternative - Alessandro Holzapfel
Improving Military Community Reintegration: The Effects of Plant-related Jobs on Military Service Member Mental and Physical Health - Alicia Thomas
Evaluating the Impacts of Climate Change on Urban Tree Performance and Survival - Teagan Young
Managing Drift in Vegetable Operations: Extension Risk Management Herbicide Workshops - Kathryn Fontenot
Native Trees for Public Gardens: Building a University Teaching Collection for Increased Student Learning, Visitor Engagement, and Carbon Sequestration - Lauren Errickson
Future Directions of Horticultural Research Among Botanical Gardens and Arboreta in the United States - Michael Opgenorth

Moderator
avatar for Michael Opgenorth

Michael Opgenorth

National Tropical Botanical Garden
Thursday September 26, 2024 1:44pm - 3:45pm HST
Lehua Suite

1:45pm HST

PH 2 - Evaluating the Effects of Controlled Atmosphere Storage on Two Georgia-grown Pecan Cultivars
Thursday September 26, 2024 1:45pm - 1:55pm HST
Pecans are an important commodity in Georgia with 180,000 planted acres in 2022. The crop undergoes quality deterioration through lipid oxidation, off-flavor development, and kernel browning in storage. Many new varieties have been introduced to the State with little known about their storage viability. Knowing the varieties performance after harvest can help growers plan for an uncertain market by reducing storage costs. The standard industry technique for storage is low temperature (0°C) cold rooms, which can quickly become expensive over long periods of time due to rising electricity costs. The addition of controlled atmosphere (CA) may possibly aid in reducing oxidation rate and kernel browning during storage. The controlled atmosphere would reduce the amount of oxygen (O2) substituted by carbon dioxide (CO2). Previous studies reported shelf-life increases after oxygen levels were reduced to 2-3% using nitrogen (N2), however carbon dioxide is less commonly seen. Half pecan kernels were hand shelled and sorted before being stored under varied conditions for up to five months. Three treatments were applied to two GA pecan varieties (‘Desirable’ and ‘Sumner’). Conditions included elevated storage temperature at 10 °C, low temperature storage (5 °C) plus CA (10% CO2 4% O2), high temperature storage plus CA, and a control of cold storage at (0 °C). Quality assessments were conducted every month for change of weight, firmness, and color values. Firmness values were conducted using MecMesin texture analyzer to penetrate the half kernel until the breakpoint was achieved. A significant difference was seen in ‘Desirable’ when comparing the days of storage against the atmospheric conditions in the chroma values with the CA treatments exhibiting higher chroma. The Sumner variety saw significant differences in the chroma after two months of storage and varied differences in lightness values throughout storage. A significant difference was seen between the two varieties in firmness values with Sumner exhibiting higher firmness.
Speakers
RC

Ramsey Corn

University of Georgia
Co-authors
AD

Angelos Deltsidis

University of Georgia
CE

Camille Esmel McAvoy

University of Georgia
NA
OG

Orestis Giannopoulos

University of Georgia
Thursday September 26, 2024 1:45pm - 1:55pm HST
South Pacific 3

1:45pm HST

CE 6 - Timing Kale Growth for Peak Nutrition and Energy Efficiency in a Vertical, Hydroponic Indoor Container Farm
Thursday September 26, 2024 1:45pm - 2:00pm HST
As entrepreneurs look to find new ways to shorten the gap between farm and table in urban communities, many are considering vertical farming as an answer to the problem of limited growing space. The aim of this experiment is to determine the optimal harvest time in weeks for vertically grown, hydroponic kale (Brassica oleracea var. acephala cv. ‘Toscano’) based on morphological data, phytonutrient concentrations, energy, and yield. After a four-week germination period, kale was grown for up to eight weeks and harvested at eight different stages of growth, based on the number of weeks spent in the vertical system. When harvested, morphological parameters were measured, and samples were collected to analyze mineral nutrient content. Electrical Energy usage data was collected and presented as: Lighting, HVAC, and Other. Data was analyzed as a Randomized Complete Block Design with three blocks. Mean plant height, fresh leaf mass, and leaf dry mass all increased with growth stage, with the largest plants being observed at stage eight. Additionally, the greatest mean quantity of dead, diseased, or unconsumable leaves of 3.27 leaves per plant was observed at stage eight. Mineral nutrient concentrations of calcium, sulfur, and manganese increased through seven weeks (stage seven), after which a decrease was observed in stage eight. Decreases in concentration during stage eight was also observed for phosphorus, potassium, and magnesium, with negligible differences in the younger stages. No differences in energy data existed for the daily mean lighting, HVAC, and Other electrical consumption across all eight stages. Harvest data collected indicates that plants should be harvested prior to stage eight to maintain mineral nutrient content and minimize dead leaves and should be considered with total energy consumption to optimize farm productivity, energy efficiency, and nutritional content of plants. Further analysis of other primary and secondary metabolites alongside total energy consumption cost is necessary to identify the best stage of harvest maturity and nutritional quality for consumers relative to energy usage and production cost.
Speakers
SB

Skyler Brazel

University of Tennessee - Knoxville
Co-authors
CS

Carl Sams

University of Tennessee
DV

Devin Vitello

University of Tennessee - Knoxville
NA
KR

Katelynn Rector

University of Tennessee - Knoxville
NA
Thursday September 26, 2024 1:45pm - 2:00pm HST
Coral 1

1:45pm HST

PUBHORT/Hort Industry - Enhancing Public Garden Experiences: Utilizing QR Codes and Videos for Plant Identification and Education
Thursday September 26, 2024 1:45pm - 2:00pm HST
Public gardens play a crucial role in promoting horticultural education and appreciation. Proper plant signage can further enhance a visitor’s learning experience. This project provides partner gardens with trusted horticulture information while further utilizing Oklahoma Gardening content, produced by Oklahoma State University Extension. Oklahoma Gardening, a research-based, how-to gardening television show, airs weekly on Oklahoma Educational Television Authority (OETA), a PBS affiliate. This project created a virtual, educational experience for visitors of participating gardens. Eleven public gardens and educational demonstration gardens located in rural and urban settings throughout Oklahoma were provided with 5-15 signs depending on the size of the garden, the availability of in-season plant material, and the applicable video content. This approach leverages the recent widespread adoption of QR codes, allowing visitors to access plant information effortlessly from Oklahoma Gardening. Many of the selected gardens provide free entrance to the public, offering a horticultural experience to all. However, this can reduce the garden’s operation budget and limit their ability to provide adequate educational signage. The objective of this project is to help these public gardens increase their horticulture educational interpretation. These QR code signs not only provide gardens with seasonally appropriate plant identification signage but also offer visitors videos about the plants they are observing. Furthermore, for open-access public gardens it can be difficult to quantify visitation. By utilizing dynamic QR codes the quantity and time of scans is captured. This allows for tracking of the usage of each sign and which plants are most popular. This information is then shared with participating gardens. Public gardens are often visited by tourists as well. This project expands Oklahoma Gardening and OSU Extension beyond television and YouTube to reach an audience in the public garden space. The dynamic QR code scans provide the phone’s registered city, state, and country, giving approximate geographic locations of garden visitors. After a year of placing the signs, we have identified clicks from 23 states, and 5 additional countries. This project was funded by Oklahoma Department of Agriculture, Food, and Forestry Specialty Crop Block Grant.
Speakers
BS

Bailey Singleton

Oklahoma State University
Co-authors
CH

Casey Hentges

Oklahoma State University
NA
Thursday September 26, 2024 1:45pm - 2:00pm HST
Lehua Suite

1:45pm HST

VSF 4 - First They’re Sweet, Then They’re Sour: The Impact of Cultivar, Berry Maturity, and Phytohormones on Blueberry Quality U
Thursday September 26, 2024 1:45pm - 2:00pm HST
Fruit quality parameters are typically reported by growers and researchers as an average. However, for small fruits such as blueberries, berry-to-berry variability in texture and flavor also impacts the consumer eating experience. The objective of this project was to capture how fruit quality uniformity varies by 1) cultivar, 2) berry maturity, and 3) exogenous phytohormone applications. From 2022-2023, analyses were conducted on individual blueberries from multiple studies carried out in commercial fields in Michigan. First, we compared the uniformity of berry weight, diameter, firmness, and total soluble solids in six northern highbush blueberry cultivars: “Duke,’ ‘Bluecrop,’ ‘Draper,’ ‘Calypso,’ ‘Elliott,’ and ‘Aurora.’ Second, we evaluated how changes in berry maturity due to delayed harvest and sequential harvest dates affected the uniformity of berry weight, diameter, firmness, total soluble solids, pH, total acidity, and aroma volatile concentrations in: ‘Duke,’ ‘Draper,’ ‘Calypso,’ and the uniformity of berry weight, diameter, firmness, and total soluble solids in ‘Bluecrop,’ ‘Elliott,’ and ‘Aurora,’ respectively. The implications of delayed harvest on the uniformity of consumer liking scores will also be discussed. Finally, we tested whether exogenous application of multiple phytohormones impacted the uniformity of berry weight, diameter, firmness, and total soluble solids in ‘Bluecrop,’ ‘Elliott,’ and ‘Aurora’. We conclude that “uniformity” is an important component of fruit quality in blueberry.
Speakers
MG

Michael Gasdick

Michigan State University
Co-authors
DD

Daniel Dick

Michigan State University
JV

Josh VanderWeide

Michigan State University
Thursday September 26, 2024 1:45pm - 2:00pm HST
Nautilus 1

1:45pm HST

WUM 3 - Glyphosate Runoff Impacting Water Quality
Thursday September 26, 2024 1:45pm - 2:00pm HST
Glyphosate is the most widely used herbicide in the world due to its relevance in agricultural practices and urban lawncare. While this herbicide is prominent in various countries, it has been continuously surrounded by controversy for the past decade. With reports of potential dangers to human health, contradicting reports from government agencies, and lawsuits against the company Monsanto, the creator of Roundup whose key active ingredient is glyphosate, there is opinion-based literature and confusion among the public. There is a plethora of published literature discussing what glyphosate is and the potential dangers to the environment; however, there is minimal research on the effects glyphosate has on water quality through runoff in urban areas. This research is aimed to assess the presence of glyphosate and its degradation product aminomethylphosphonic acid (AMPA) in the waterways of Stillwater, OK. This is done by collecting water samples where runoff was present in urban areas. It is important to understand the presence of glyphosate in runoff to view the persistence of this chemical within waterways and different environments. Keywords: glyphosate, AMPA, water quality, runoff, controversy, samples
Speakers
NS

Natalie Santos

Oklahoma State University
Co-authors
JM

Justin Moss

Oklahoma State University
NA
Thursday September 26, 2024 1:45pm - 2:00pm HST
Coral 2

1:59pm HST

Citrus Crops 3 (CITR 3)
Thursday September 26, 2024 1:59pm - 3:45pm HST
A Glimpse of The Future of Citrus in Florida – The Millennium Block - Flavia Tabay Zambon
Lessons from Evaluating New Varieties for the Indian River Grapefruit Industry - Flavia Tabay Zambon
Florida Citrus Rootstock Selection 5th Edition: Artificial Intelligence Enhanced Mobile Application for Growers - Andres GonzalezNeira
Australian Microcitrus-Derived Hybrids: Field Performance in Florida Under HLB Endemic Conditions - Matthew Mattia
The Citrus Genome Database: A Resource for Citrus Research and Crop Improvement - Jodi Humann
Comparative Transcriptomic and Metabolomic Studies Provide Insights into Early Tolerance Response of Citrus to CLas Infection - Zimmy Wang
Exploring Leaf Nutrients and Fruit Quality Attributes Relationship in Fresh Market Citrus Using Artificial Neural Networks and Linear Regression Models - Shankar Shrestha


Moderator
FT

Flavia Tabay Zambon

University of Florida - IFAS - IRREC
Thursday September 26, 2024 1:59pm - 3:45pm HST
South Pacific 2

1:59pm HST

Herbs, Spices, and Medicinal Plants 2 (HSMP 2)
Thursday September 26, 2024 1:59pm - 3:45pm HST
Hydroponic Production of Seed Ginger Rhizomes in Virginia - Christopher Mullins
Enhancing Monoterpene Indole Alkaloid Production in Catharanthus roseus Through Controlled Environment Cultivation and Hormone Applications - Matthew Housley
Multipronged Strategies to Combat Seed-Piece and Soil-borne Diseases of Ginger - Zelalem Mersha
Seed emergence of Fagonia indica, a plant with potential chemistry active against breast cancer. - Clinton Shock
Impact of Polyploid Induction on Apigenin Production in Parsley - Rebekah Maynard
Alzheimer’s Disease: Prospecting for Sterubin in California Yerba Santa - Clinton Shock
Genomic Variation in Wild Sabadilla (Schoenocaulon officinale, Melanthiaceae) Populations for Key Phenotypic Traits of Interest for Domestication and Breeding - Albert Radloff

Moderator
RM

Rebekah Maynard

University of Georgia
Thursday September 26, 2024 1:59pm - 3:45pm HST
Kahili

1:59pm HST

Nursery Crops 2 (NUR 2)
Thursday September 26, 2024 1:59pm - 3:45pm HST
Fine-tuning Substrate Stratification Ratios for Shrubs and Flowers - Jeb Fields
Engineered Substrates Improve Nitrogen, Phosphorus, and Water Retention in Nursery Container Production - Henry Gonzalez Hernandez
A 2-Dimensional Analysis of How Root Architecture and Morphology Are Influenced by Stratified Substrate Systems - Kristopher Criscione
Predicted Drought Tolerance of Cephalanthus occidentalis L. for Use in Managed Landscapes - John Larsen
Comparative microbial diversity analysis and isolation of plant growth-promoting rhizobacteria from roundleaf buffaloberry (Shepherdia rotudifolia) - Amita Kaundal
Navigating the Interplay of Climate Stress and Pest Pressure in Shade Tree Nursery Production: Insights from Oregon and Tennessee - Lloyd Nackley
The Effects of Supplemental Nickel on Mouse Ear Disorder of Three Diospyros Species - Alyssa Headley
Moderator
JF

Jeb Fields

LSU AgCenter Hammond Research Station
Thursday September 26, 2024 1:59pm - 3:45pm HST
South Pacific 4

1:59pm HST

Vegetable Crops Management 5 (VCM 5)
Thursday September 26, 2024 1:59pm - 3:45pm HST
Evaluation of Wireworm Resistant Sweetpotato Cultivars in Western Washington - Laura Schulz
Variation in Toxic Element Presence in Sweetpotato Storage Roots From A Small Plot Trial: Sampling Implications - Arthur Villordon
Striving to stay clean: Production of sweetpotato nuclear stock used for certified seed growers in North Carolina - Christie Almeyda
Effects on yield, quality, sugar content and soil health indicators of foliar and soil applied Chlorella vulgaris in ‘Beauregard’ sweetpotato (Ipomoea batatas [L.] Lam). - Brian Ward
The Effect of Potassium Fertilization on Potato Tuber Nutrition in the Columbia Basin of Oregon - ruijun qin
Predicting Potato Tuber Yield Through Hyperspectral Signals and Machine Learning - Ravinder Singh
Evaluating King Stropharia Mushroom as an Intercrop in Asparagus and Tomato Production - Olalekan Sipasi
Moderator
LS

Laura Schulz

Washington State University
Thursday September 26, 2024 1:59pm - 3:45pm HST
South Pacific 1

2:00pm HST

CE 6 - Effects of Beneficial Bacterial Endophytes on Growth of Lettuce Plants, Transcriptome, and Root Microbiome in Hydroponic Systems
Thursday September 26, 2024 2:00pm - 2:15pm HST
Controlled environment agriculture will play an important role in feeding the increasing world population as urbanization is expanding, and arable land is decreasing. Higher yields will help offset the initial high cost for building hydroponic production facilities. Beneficial bacterial endophytes have been receiving more attention in sustainable agriculture practices because they can promote plant growth, enhance nutrient uptake, and inhibit pathogen growth. The Institute for Advanced Learning and Research has established a bacterial endophyte library of more than 2000 strains and found that some bacterial endophytes significantly increased the growth of tall fescue KY31 in vitro, up to 8-fold compared with untreated control plants. In previous paper, we reported that Pseudomonas psychrotolerans IALR632 significantly promote lettuce growth in hydroponic systems. In this study, we investigated the molecular and microbiological mechanisms these bacteria exhibit for plant growth promotion in hydroponic systems through plant gene expression with RNAseq and root bacterial community changes through microbiome analysis after bacterial inoculation. Lettuce (Lactuca sativa) cultivar ‘Green Oakleaf’ was inoculated with Pseudomonas psychrotolerans IALR632 one week after seeds were sown and transplanted to nutrient film technique (NFT) hydroponic units one week after bacterial inoculation. Samples were taken at 4, 10, and 15 days after lettuce seedlings were transplanted for gene expression analysis. Root samples were taken 15 days after transplantation for microbiome analysis. Anosim, NMDS, and PCoA analyses indicated bacterial community changes in inoculated plants. The top genus relative abundance was unclassified bacteria with 87% in IALR632 treatment and 85% in control (p=0.0136). In the next top 24 genus’s relative abundance, IALR632 inoculation dramatically increased Sediminibacterium, Hyphomicrobium, Sphingobium, Devosia, Mycobacterium, Rhodoplanes, and Runella by 68%, 114%, 72%, 158%, 513%, 103% and 1920%, respectively, and reduced Methylotenera, Rhizobium, and Sphingomonas by 68%, 62% and 45%, respectively. RNAseq data showed that there were 135, 2059, and 9319 DEG between the control and bacterial treatment at 4, 10, and 15 days, respectively. These DEG are being analyzed for pathways involved in plant growth promotion.
Speakers
CM

Chuansheng Mei

Institute for Advanced Learning and Research
Co-authors
RC

Robert Chretien

Institute for Advanced Learning and Research
NA
SA

Sajeewa Amaradasa

Institute for Advanced Learning and Research
NA
SL

Scott Lowman

Institute for Advanced Learning and Research
NA
Thursday September 26, 2024 2:00pm - 2:15pm HST
Coral 1

2:00pm HST

CITR 3 - A Glimpse of The Future of Citrus in Florida – The Millennium Block
Thursday September 26, 2024 2:00pm - 2:15pm HST
For the past two decades, Florida citrus production has undergone a 75% reduction due to Huanglongbing (HLB), a disease caused by Candidatus Liberibacter asiaticus and vectored by the Asian Citrus Psyllid (ACP, Diaphorina citri). To combat this threat, breeding programs have been developing new varieties, seeking those tolerant to HLB while possessing other desirable traits and providing a long-term solution for the citrus industry. The Indian River Research and Education Center is leading this effort by planting new scion and rootstock varieties in four independent trials at the Millennium Block in 2019. One trial consists of 18 grapefruit-pummelo hybrid scions grafted onto three rootstock varieties, totaling 54 combinations (Trial 1). The other three trials are rootstock trials, where ‘Ray Ruby’ grapefruit (Trial 2), ‘Glenn Navel’ sweet orange (Trial 3), and ‘UF-950’ mandarin (Trial 4) varieties are grafted onto 32 rootstocks. The Millennium Block is home to 5,500 trees. Complete data for the 2023/24 season was collected, evaluating fruit yield, weight, size, and juice quality across all trials except for the mandarins, which have yet to set and keep a harvestable crop. Fruits were categorized into “good fruit” (based on shape, size, and maturity) and “bad fruit” (including visually HLB-affected fruit and off-bloom fruit). One of the 18 scions in Trial 1, a grapefruit-orange hybrid with golden flesh and high juice content called ‘Triumph,’ was discovered through a fortuitous mistake, yielding over 19,000 lb/ac of “good fruit” when grafted onto X-639, and had a Brix of 8.18. ’Triumph’ exhibits visual tolerance to HLB, with minimal to no affected fruit and no leaf symptoms. Of the red flesh grapefruit, ‘UF-914’ grafted onto ‘US-942’ and ‘X-639’ yielded close to 12,000 lb/ac of “good fruit” each, with juice Brix between 8-9. The traditional ‘Ray Ruby’ grapefruit has produced more boxes per acre grafted onto UFR-15 (close to 8,000 lb/ac) than US-942 and Sour Orange. Meanwhile, ‘Glenn Navel’ sweet orange yields more boxes when grafted onto US-942 (approximately 3,800 lb/ac), UFR-17, and Kuharske. The rootstock trials reveal that grapefruit and sweet orange scions require distinct rootstock characteristics to achieve the best yields. Data gathered by these trials are essential for growers to make informed decisions about which varieties to plant compared to the available conventional scions.
Speakers
FT

Flavia Tabay Zambon

University of Florida - IFAS - IRREC
Co-authors
MH

Macselynia Hossain

University of Florida
NA
MA

Mark A. Ritenour

University of Florida
NA
RD

Ronald D. Cave

University of Florida
NA
Thursday September 26, 2024 2:00pm - 2:15pm HST
South Pacific 2

2:00pm HST

HSMP 2 - Hydroponic Production of Seed Ginger Rhizomes in Virginia
Thursday September 26, 2024 2:00pm - 2:15pm HST
The length of field growing season in the temperate and subtropical regions of the United States including Virginia, does not allow ginger (Zingiber officinale) rhizomes to mature naturally. As a result, saving rhizomes as seeds is often impossible and the supply of seed ginger rhizomes (seeds) has been mostly from Hawaii. To mitigate this challenge, Cooperative Extension at Virginia State University attempted to produce ginger seeds hydroponically in a greenhouse for two years. In 2022/23, cultivar Chinese Ginger (4-6 buds/rhizome) was presprouted in the greenhouse using 1-gallon pots filled with soilless media in January and transplanted into 20-gallon fabric containers filled with soilless media or pine bark on May 6 or 17, 2023. Plants were fertigated on weekdays with a nutrient stock solution containing 6 oz 4-18-38 plus micros, 3 oz magnesium sulfate and 8 oz calcium nitrate per gallon. Seed harvests took place from January 15 to March 18, 2024. The yield was significantly higher with soilless media (12.7 lb./plant) than with pine bark (11.1 lb./plant) although the marketable yield was not statistically different. Plants in soilless media were difficult to harvest (heavy and wet soil, tangled roots). Marketable yield was the highest for plants harvested from 240-269 days after transplanting (DAT), followed by 270-289 DAT. Harvests after 290 DAT had 37-53% culls. The overall yield was not different in terms of transplanting dates, but May 6 transplanting had significantly less marketable rhizomes compared to May 14 transplanting. The first-year results favored using pine bark and harvesting 260-290 DAT. In 2023/24, ‘Blue Ring’ and ‘Yellow Ginger’ were added. Pre-sprouting started in March and transplanting occurred in late May 2023 with only pine bark as the media type. Fertigation and irrigation were discontinued in mid-December to allow media to dry. The yield of ‘Chinese Ginger’ raged from 11.3 lb./plant in early November 2023 to 13.7 lb./plant in late February 2024, indicating possible early harvests and curing if storage space is available, which would avoid heating greenhouse in deep winter. ‘Chinese Ginger’ had the highest yield (13.8 lb./plant), followed by ‘Yellow Ginger’ (12.5 lb./plant) and ‘Blue Ring’ (9.7 lb./plant). All three cultivars had 10-20% culls due to rotting (disease) and scarring. Our results proved the feasibility of ginger seed production in local greenhouses and the great yield with a hydroponic system. We will refine the system and test the quality of seeds in field and high tunnels in 2024.
Speakers Co-authors
CM

Christopher Mullins

Virginia State University
SG

Sanjun Gu

Virginia State University
Thursday September 26, 2024 2:00pm - 2:15pm HST
Kahili

2:00pm HST

NUR 2 - Fine-tuning Substrate Stratification Ratios for Shrubs and Flowers
Thursday September 26, 2024 2:00pm - 2:15pm HST
The ornamental production industry utilizes either controlled greenhouse or open-air nursery production systems. Both rely upon the use of soilless substrates, with regular application of water and mineral nutrients, to maintain profitability and quality crop growth and development. However, the leading base substrates components used, peat moss and bark, present sustainability concerns for producers. Peat moss sustainability concerns surround harvest, supply, and cost (environmental, social, and economic; three tiers of sustainability) of the material. Pine bark sustainability in production is due to inefficiency in water and mineral nutrient retention (environmental, social, and economic). Nevertheless, a solution to help improve the sustainability of both substrates across the greenhouse and nursery industry has developed. Soilless substrate stratification is a practical management strategy that entails layering two unique substrates, either derived from the same substrate or different substrates, atop one another in the container. Stratifying substrates has been shown to reduce peat use and reliance in the greenhouse industry by upwards of 50%. Moreover, stratifying substrates can reduce irrigation and fertilizer applications by 25- and 20%, respectively. To date, stratified substrate research has utilized an even 50:50 stratified depth layer partition. As growers adopt this technique, more understanding of the balance and opportunities is needed. Thus, a series of experiments was developed to explore varying ratios of stratification. In two experiments, popular greenhouse (Petnas) and nursery (Rosa) crops were grown in different stratified depth layer ratios with peat-based (greenhouse) and bark-based (nursery) systems. Ratios included a non-stratified treatment (100% filled), a 75:25 percent by vol. layer partition, a 50:50, and a 25:75. In the greenhouse experiment, peatlite mix was layered over unscreened bark and irrigation was lysimeter-actuated. In the nursery experiment, fine bark particles were layered over coarse particles. Moreover, different fertilizer rates were applied (low, medium, high). The results showed in the greenhouse study, a Pentas crop can be grown with equal growth (and similar quantities of water) as traditional greenhouse crop when ≥50% peatlite is used by vol. In the nursery experiment, low fertilizer application rates can be used to grow a crop similar to a traditional nursery-grown crop when grown in a stratified system. While there are discrete differences, it primary take away is that stratification does not need to be overly technical to generate impact and improve efficiency; however, there is a limit to the ability to use “filler” material which tends to be about 50% of the volume.
Speakers
JF

Jeb Fields

LSU AgCenter Hammond Research Station
Co-authors
KC

Kristopher Criscione

LSU AgCenter Hammond Research Station
Thursday September 26, 2024 2:00pm - 2:15pm HST
South Pacific 4

2:00pm HST

PUBHORT/Hort Industry - Educational Signage in a Community Garden can Assist in Volunteer Learning
Thursday September 26, 2024 2:00pm - 2:15pm HST
Volunteering issues in community gardens have been an ongoing problem and have resulted in high turnover and untrained volunteers that may not have the skills to appropriately staff a community garden. The problem of having to train or have dedicated staff at a garden to assist volunteers is that often community gardens are not funded, or garden staff are stretched too thin. To inspect factors in volunteerism in community gardens, researchers sent out a ten-question survey to head community garden leaders (N=51) across the U.S. Overall, researchers found that many gardens perceive educational opportunities and the people that attend the garden as successful elements, while volunteer retention and education, along with signage issues, were the most prevalent problem. Finally, when asked about signage, most signs turned out to be purely informative and attractive, with few playing educational roles. Researchers concluded that educational signage may play an important role in the garden that many community gardens are missing. To understand further how educational signage plays a role in people’s understanding of a subject, researchers have developed another survey that is currently being distributed to the public. The data from this survey will allow researchers to more effectively use signage to not only attract but educate and train volunteers to relieve some of the burden from community garden staff.
Speakers
JT

Jonah Trevino

Texas Tech University
NA
Co-authors
CS

Catherine Simpson

Texas Tech University
NA
LF

Laura Fischer

Texas Tech University
NA
LT

Leslie Thompson

Texas Tech University
NA
VB

Vikram Baliga

Texas Tech University
NA
Thursday September 26, 2024 2:00pm - 2:15pm HST
Lehua Suite

2:00pm HST

VCM 5 - Evaluation of Wireworm Resistant Sweetpotato Cultivars in Western Washington
Thursday September 26, 2024 2:00pm - 2:15pm HST
Sweetpotato (Ipomoea batatas) is a nutritious, productive, and resilient crop that is grown worldwide and is gaining popularity throughout the U.S. In western Washington, wireworms (Agriotes lineatus, A. obscurus, and Limonius canus) are the primary pest impacting sweetpotato production. Wireworm resistant cultivars can provide an effective and sustainable pest management tool for growers. A field experiment in Mount Vernon, WA included nine sweetpotato cultivars and breeding lines: wireworm-susceptible cultivars Bayou Belle, Beauregard, Covington, and Orleans; wireworm-resistant cultivars Cascade and Monaco; and wireworm-resistant breeding lines USDA-04-136, USDA-04-284, and USDA-04-791. Storage roots were graded according to USDA sweetpotato categories and root weight, number, and wireworm damage [Wireworm-Diabrotica-Systena (WDS) severity index] were measured. Marketable yield ranged from 22 t/ha (USDA-04-136) to 57 t/ha (‘Bayou Belle’) (p
Speakers
LS

Laura Schulz

Washington State University
Co-authors
CM

Carol Miles

Washington State University
JB

Jacob Blauer

Washington State University
NA
LM

Laurel Moulton

Washington State University
NA
LN

Louis Nottingham

Washington State University
NA
PW

Phil Wadl

United States Department of Agriculture, Agricultural Research Service
SS

Srijana Shrestha

Washington State University
NA
Thursday September 26, 2024 2:00pm - 2:15pm HST
South Pacific 1

2:00pm HST

VSF 4 - Phytohormone and Plant Growth Regulator Use in Blueberry Production – A Review
Thursday September 26, 2024 2:00pm - 2:15pm HST
Plant growth regulators (PGRs) are natural or synthetically derived plant hormones that play a significant role in shaping plant growth and development. In tree fruit and table grape production, PGRs are commonly employed to address production challenges, including modulating crop load and improving fruit size, coloration, and quality. Meanwhile, their use in berry crops such as blueberry remains limited despite the prevalence of production challenges and the availability of registered PGRs for other fruit crops. This review summarizes the existing literature regarding PGR use in blueberry, as well as the current needs for research on PGRs going forward. First, considering the large increase in U.S. blueberry production over the past decade, we highlight the lack of PGRs registered and utilized in blueberry compared to other fruit crops. Second, we summarize the current literature on the utility of PGRs to mitigate challenges in blueberry production, including cold hardiness and frost protection, dormancy release, fruit size and crop load management, fruit quality improvement, post-harvest shelf-life extension. Finally, this work presents future opportunities for research involving PGRs in blueberry production. As blueberry production continues to increase in the U.S. and globally, the need to mitigate production challenges using PGRs will likely also increase.
Speakers
DD

Daniel Dick

Michigan State University
Co-authors
JV

Josh VanderWeide

Michigan State University
Thursday September 26, 2024 2:00pm - 2:15pm HST
Nautilus 1

2:00pm HST

WUM 3 - Assessing Drip Irrigation as an Alternative to Micro-sprinklers During Strawberry Establishment in Southern California
Thursday September 26, 2024 2:00pm - 2:15pm HST
The escalating regulatory pressure to achieve sustainable groundwater use in California will demand improved irrigation efficiency. Even though approximately 80 to 90% of the sprinkler-applied water to a strawberry crop is lost through runoff, deep percolation and evaporation, all the strawberry fields in Ventura County are still irrigated with overhead sprinklers during crop establishment. This study quantified differences in water use, yield, canopy coverage and root depth between drip tape and micro-sprinkler irrigation during crop establishment at a commercial field located in Oxnard, CA during the 2023-2024 growing season. Treatments consisted of three irrigation methods used during the first five weeks: 1) primarily drip tape (DT), 2) micro-sprinklers only (MS), and 3) a combination of drip tape and micro-sprinklers (C). The irrigation scheduling of the MS treatment was defined by the irrigator (grower standard), while the DT and C treatments were guided by tensiometers and field observations. All other production practices remained the same. Each treatment was replicated four times in a randomized complete block design, with an area of approximately 1.7 acre per plot (40 beds of 350ft long). Treatments were carried out for 35 days from planting (Oct 5), after which drip irrigation became the only irrigation method. Total water use during establishment was very similar among treatments: 3.9, 3.6 and 4.0 acre-in for DT, C and MS, respectively. With four plant rows and three drip lines per bed, the DT treatment was irrigated for longer than anticipated to assure uniform soil moisture around the plant roots. Marketable yield until Mar 14 was 4,583, 4,229 and 4,297 lb/acre for DT, MS and C, respectively. Although not statistically significant, DT yield was 8.4% greater than MS (p-value = 0.802), and 6.7% greater than C (p-value = 0.865). Canopy cover trends were very similar between DT and C, while MS was between 13 and 29% lower than DT from 48 to 61 days after planting. Canopy coverage equalized at 90 days after planting after significant precipitation during Dec and Jan. Average root depth of DT was 38 and 19% greater than MS for 15 and 28 days after planting, respectively. In summary, this study found equal or superior crop performance of DT compared to MS during strawberry establishment. We expect that increasing the number of drip tape per bed from three to four would significantly decrease the irrigation time needed to provide ideal soil moisture, consequently decreasing water use.
Speakers
AB

Andre Biscaro

UC Cooperative Extension
Co-authors
MV

Maripaula Valdes Berriz

University of California Cooperative Extension
NA
OD

Oleg Daugovish

University of California Cooperative Extension
RC

Raul Coronado

GoodFarms
NA
SZ

Siomara Zendejas

University of California Cooperative Extension
NA
Thursday September 26, 2024 2:00pm - 2:15pm HST
Coral 2

2:00pm HST

Postharvest Interest Group Meeting
Thursday September 26, 2024 2:00pm - 3:00pm HST
Moderator
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Thursday September 26, 2024 2:00pm - 3:00pm HST
Sea Pearl 4

2:14pm HST

Vegetable Breeding 2 (VGBR 2)
Thursday September 26, 2024 2:14pm - 4:00pm HST
Genome-wide Association Study and Genome Prediction of Bolting Trait in Spinach - Hanan Mohammedsaeed Alkabkabi
Towards the Improvement of Lettuce for Heat Tolerance Adapted to Controlled Environment Agriculture - German Sandoya Miranda
Root Phenotyping in Chile Pepper: Key Steps and Challenges with the RhizoVision Explorer - Ehtisham Khokhar
Towards Mechanical Harvest: Leveraging Genomic Selection to Increase Fruit Firmness in Fresh Market Tomato - Jessica Chitwood-Brown
Genome-wide Association Study and Genome Prediction of Tallness Trait in Spinach - Ibtisam Alatawi
Capitalizing on the Global Capsicum Core Collection to Advance Pepper Breeding - Derek Barchenger
Private-public Partnership for Sustainable Cucurbit Breeding and Production in Asia - Narinder Dhillon

Moderator
JC

Jessica Chitwood-Brown

University of Florida
Thursday September 26, 2024 2:14pm - 4:00pm HST
South Pacific 3

2:15pm HST

CE 6 - Soybean Speed Breeding: Optimizing Photoperiod for Maximizing Yield and Minimizing Time
Thursday September 26, 2024 2:15pm - 2:30pm HST
Speed breeding is a cutting-edge technology, that utilizes controlled environments to significantly reduce plant generation time, thereby accelerating breeding and research programs. The manipulation of temperature, irrigation, phytohormones, and light are the main ways to reduce plant cycles in speed breeding programs. However, changing these factors can result in decreased yield efficiency, which can also affect the quality of a speed-breeding program. This study aimed to increase seed production without increasing harvest time in soybean plants, a short-day plant, by using different photoperiod regimes. Two soybean (Glycine max) varieties, S16-14801C and CZ7570LL, were grown from seeds in 11-L pots containing peat moss-based substrate in growth chambers with controlled temperature (27 ± 0.5 ˚C), CO2 (475 ± 15 µmol mol-1), humidity (70 ± 5.0%), and light (300 ± 5 µmol m-2 s-1 at table; 20% blue, 10% green, 70% red). One week after germination, seedlings were exposed to four different photoperiod regimes: i) 10 h (0 w at 18 h); ii) two weeks at 18 h and then 10 h (2 w at 18 h); iii) four weeks at 18 h and then 10 h (4 w at 18 h) and iv) six weeks at 18 h and then 10 h (6 w at 18 h). The light fixtures were not adjusted over plant height following industry practices. The plants were harvested ten days after 95% of the pods had attained maturity (R8 stage). For both varieties, the number of pods and seeds and seed weight per plant increased linearly, with the increase in the number of weeks at 18 h. Thus, the number of pods, seeds, and seed weight of plants at 6 w at 18 h were at least 5-fold higher than in plants at 0 w at 18 h. Similarly, plants grown at 6 w at 18 h presented 4-fold higher biomass than plants grown at 0 w at 18 h. However, the increased seed yield and biomass accumulation did not result in a longer plant cycle; plants of both varieties at 6 w at 18 h were harvested 32 days before plants at 0 w at 18 h. Here, we demonstrated that seed yield can be increased and harvest time decreased by manipulating the photoperiod. These findings can help plant breeders in identifying the most suitable method for growing soybean plants in a shorter period, while also ensuring high seed production.
Speakers
avatar for Cristiane da Silva

Cristiane da Silva

Postdoctoral Research Scholar, North Carolina State University
I'm Cristiane, a plant physiologist with experience in plant biochemistry and plant responses to abiotic stress. Currently, I'm a post-doc at NCSU studying the effects of light on plant life cycles to expedite breeding purposes in crop and tree species. When I'm not working, I enjoy... Read More →
Co-authors
CC

Cristian Collado

North Carolina State University
NA
RH

Ricardo Hernandez

North Carolina State University
NA
Thursday September 26, 2024 2:15pm - 2:30pm HST
Coral 1

2:15pm HST

CITR 3 - Lessons from Evaluating New Varieties for the Indian River Grapefruit Industry
Thursday September 26, 2024 2:15pm - 2:30pm HST
Citrus greening is one of the deadliest bacterial diseases in citrus production. Caused by Candidatus Liberibacter asiaticus (CLas) and vectored by the Asian Citrus Psyllid (ACP, Diaphorina citri), the disease has devastated Florida’s citrus industry, reducing production by over 75% during the last twenty years. The Indian River Region, known for its premier grapefruit production, has suffered an intense decline in yield and acreage. Growers in the region have been fighting the pathogen and its insect vector, however, a long-term solution is required for sustainable grapefruit production. As no HLB resistance is known in commercially available cultivars, the University of Florida Breeding Program has bred new grapefruit hybrids with potential HLB tolerance. Plants developed through the program need to be field-tested. This study was initiated to evaluate new fresh grapefruit scion and rootstock breeding materials for HLB-tolerant. In collaboration with twelve growers across the state, a large trial was planted between 2020 and 2022 with 40 plots, each with forty-two scion/rootstock combinations totaling 12,000 trees. Among other tree growth data collected, fruit yield and quality were measured this season between October 2023 and March 2024. Results confirm that 'Jackson' grapefruit has some HLB tolerance, possibly due to its vigorous nature. However, its high fruit drop and inconsistent fruit set are persistent grower concerns. Among the newly developed grapefruit hybrids, 'UF N40-16-11-7' grafted onto SuperSour #1 and UFR-5, and the pummelo hybrid 'UF KW-50-1' grafted onto X-639 had low HLB disease indexes, equivalent to ‘Jackson’. On trees fruiting for the first time, the pummelo hybrid ‘UF KW-1-50’ grafted onto SuperSour #1 had the highest yield, mainly due to the pummelo heritage, followed by red grapefruit ‘UF N40-16-11-7’ also grafted onto SuperSour #1 and ‘Rio Red’ onto US-942. With tree ages ranging from 2 to 4 years, further data collection is needed to determine sustained yield and fruit quality. These results can help determine which combinations are most HLB-tolerant and best for planting in the Indian River Region.
Speakers
FT

Flavia Tabay Zambon

University of Florida - IFAS - IRREC
Co-authors
AG

Andres GonzalezNeira

University of Florida
MA

Mark A. Ritenour

University of Florida
NA
Thursday September 26, 2024 2:15pm - 2:30pm HST
South Pacific 2

2:15pm HST

HSMP 2 - Enhancing Monoterpene Indole Alkaloid Production in Catharanthus roseus Through Controlled Environment Cultivation and Hormone Applications
Thursday September 26, 2024 2:15pm - 2:30pm HST
The monoterpene indole alkaloids (MIAs) Vincristine and Vinblastine are medicinally important anti-tumor chemotherapy drugs derived from Catharanthus roseus metabolites, but the production of these alkaloids is difficult due to low levels in plant tissue and cost-prohibitive extraction methods. Cultivation of C. roseus in controlled environment systems could allow for increased production of desirable metabolites. There currently is a lack of knowledge concerning hydroponic and controlled environment production of C. roseus for alkaloid production. In two separate experiments, C. roseus was grown in deep water culture hydroponics (DWC) to determine its suitability for hydroponic cultivation and the effect of applying the plant hormones jasmonic and salicylic acids on MIA levels. In experiment 1, two cultivars, ‘Sunstorm Mix’ and ‘Cora Mix’, were cultivated under greenhouse conditions in DWC with two substrates, rockwool (Grodan AO 36/40) or 75% peat: 25% coir ( Jiffy Preforma *HP* DJ) and two fertilizer solution concentrations [150 or 300 mg/L N using a 15N-2.2P-12.4K water-soluble fertilizer (Jack’s Professional® LX 15-5-15 Cal-Mag LX)]. Shoot and root fresh and dry weight (SFW, SDW, RFW, RDW), leaf chlorophyll (CCI) and anthocyanin content (ACI), and total alkaloids (TA) were analyzed. The most favorable combination for many plant growth parameters measured was ‘Sunstorm Mix’ with Jiffy at 150 mg/L N, showing higher SFW, SDW, RFW, and RDW compared to other combinations. In experiment 2, ‘Sunstorm Apricot’ was cultivated under greenhouse conditions in DWC with the same75% peat: 25% coir using a modified Sonneveld solution at 150 mg/L N. Jasmonic and salicylic acids were applied at three rates and at two time points [34 and 41 days after transplant (DAT)]. Two sets of leaf samples were collected at 6,12,18 and 24 hours after application (HAA) and analyzed for the MIAs Vincristine and Vinblastine. Plants were destructively harvested 47 DAT for measurement of growth parameters FSW, FRW, DSW, and DRW. Together, these experiments assisted in improving the crop production for alkaloid use in healthcare and other applications.
Speakers
MH

Matthew Housley

University of Georgia
Co-authors
AM

Anish Malladi

University of Georgia
NA
JL

Jason Lessl

University of Georgia
NA
RF

Rhuanito Ferrarezi

University of Georgia
NA
RB

Robin Buell

University of Georgia
NA
Thursday September 26, 2024 2:15pm - 2:30pm HST
Kahili

2:15pm HST

NUR 2 - Engineered Substrates Improve Nitrogen, Phosphorus, and Water Retention in Nursery Container Production
Thursday September 26, 2024 2:15pm - 2:30pm HST
Container nursery production is the fastest-growing sector in the nursery industry. High volumes of runoff containing nitrogen (N) and phosphorus (P) from container production result in wasted high-quality fresh water, loss of costly applied fertilizer, and increased risk of nutrient management regulations, especially near receiving waters prone to eutrophication. The authors hypothesize that stratified substrates, in which a fine textured substrate is placed atop a coarse substrate amended with ferrous sulfate (FeSO4), can reduce water use and decrease N and P losses while yielding a high-quality container crop. This research was conducted at the Horticulture Teaching and Research Center in Holt, Michigan on three replicate simulated nursery pads per treatment, each having 45 containers consisting of Buddleja x ‘Miss Violet’, Ilex crenata ‘FARROWSK6’, Hydrangea paniculata ‘Limelight’, Physocarpus opulifolius ‘Seward’, Cornus sericea ‘SMNCSBD’, Cotinus coggygria ‘MINCOJAU3’, Rosa x ‘ChewDelight’. Substrate treatments consisted of an 85:15 (by vol.) pine bark:sphagnum peat uniform profile (Conv), an 85:15 pine bark:sphagnum peat uniform profile fully amended with 3 kg/m3 FeSO4 (Conv Fe), stratified substrate (Strat) in which fine sphagnum peat amended bark substrate was atop a coarse bark substrate, and stratified substrate with the coarse bark layer amended with 3 kg/m3 FeSO4 FeSO4 (Strat Fe). All plants were micro-irrigated with a spray stake. Irrigation water usage, N, and P leaching were quantified and compared. Preliminary results indicate that lower amounts of N leached from Strat (12 mg L-1, p = 0.03) and Strat Fe (13 mg L-1, p = 0.02) compared to Conv (23 mg L-1). Similarly, lower P was found in leachate from Strat (6.33 mg L-1, p = 0.01) and Strat Fe (6.74 mg L-1, p = 0.02) compared to Conv (11.78 mg L-1). These preliminary results, in addition to leaching fraction and growth index, will be discussed in this presentation.
Speakers
HG

Henry Gonzalez Hernandez

Michigan State University
Co-authors
JS

Jacob Shreckhise

USDA-ARS, U.S. National Arboretum
JO

James Owen

USDA-ARS
Jim Owens is a USDA-ARS Research Horticulturist located at the Application Technology Research Unit in Wooster, OH. Jim received his B.Sc. in Plant and Soil Science at the University of Kentucky, his M.Sc. in Environmental Science at the University of Rhode Island, and Ph.D. at North... Read More →
RF

Rodney Fernandez

Michigan State University
NA
Thursday September 26, 2024 2:15pm - 2:30pm HST
South Pacific 4

2:15pm HST

PUBHORT/Hort Industry - Marigolds - An Overlooked Cut Flower Alternative
Thursday September 26, 2024 2:15pm - 2:30pm HST
Especially the floral industry is dependent on fashion trends and changes in taste that dictate the colors and styles of arrangements. As it turns out, when it comes to marigold cut flowers, certain customers have been traditionally underserved in the southeastern United States. Research conducted by the Louisiana State University and Mississippi State University indicate that Marigolds are not only a very viable alternative to traditional cut flowers but also a worthwhile investment for commercial growers. Further research indicates that specific cultures and religions prefer marigolds for celebrations and holidays representing a relatively large customer base with considerable purchasing power that has previously gone unnoticed by the floral industry in the southeastern United States. Findings suggest marigolds have the potential to increase the floral industry’s market share and attract new customers that it previously failed to attract. Additionally, many celebrations and holidays for which marigolds are desired are during a time of the year when demand for flowers is typically low. Marigolds should therefore be considered for season extension.
Speakers
AH

Alessandro Holzapfel

Louisiana State University Agricultural Center
Co-authors
AA

Achyut Adhikari

Louisiana State University Agricultural Center
NA
KF

Kathryn Fontenot

LSU AgCenter
Thursday September 26, 2024 2:15pm - 2:30pm HST
Lehua Suite

2:15pm HST

VCM 5 - Variation in Toxic Element Presence in Sweetpotato Storage Roots From A Small Plot Trial: Sampling Implications
Thursday September 26, 2024 2:15pm - 2:30pm HST
The overarching goal of FDA’s Closer to Zero (C2Z) action plan is to reduce dietary exposure to contaminants, in foods commonly eaten by babies and young children, to as low as possible while maintaining access to nutritious foods. In addition to establishing action levels for specific toxic elements (TEs), C2Z proposes to develop new and improved testing methods to measure lower levels of contaminants in food and monitor levels over time to determine potential adjustments to proposed action levels. These proposed testing and monitoring activities represent potential added costs to the producer. The sweetpotato (Ipomoea batatas L.) is a leading baby food raw product but very little information is available on the appropriate frameworks for optimal sampling procedures to ensure accuracy and precision of surveys, especially at the field scale. A field trial to investigate the role of commonly used soil amendments in reducing storage root accumulation of arsenic (As), cadmium (Cd), and lead (Pb) revealed interesting trends that merits further investigation. Three random U.S. No.1-sized storage roots were sampled from each of three random plants from each of two unamended (control) plots (plot size=12’ x 3.3’) and analyzed for TE presence at a commercial laboratory. The Pb and Cd content of storage roots from cultivars ‘Bayou Belle’ (BB) (SDs: Cd=1.1, Pb=1.3) and ‘Beauregard’ (BX) (SDs; Cd=1.8 Pb=1.3, Cd=) showed more variability relative to As (SDs: BB=0.5, BX=0.6). There were no differences between two cultivars for all TEs measured. A possible follow-up study could investigate plant- or soil-based variables that contribute to variation in Pb and Cd accumulation. Such findings can be used to improve the accuracy and precision of sampling approaches to enable producers to meet C2Z goals, especially as it concerns sampling of storage roots for monitoring and enforcement purposes.
Speakers
AV

Arthur Villordon

Professor, Louisiana State University AgCenter
Thursday September 26, 2024 2:15pm - 2:30pm HST
South Pacific 1

2:15pm HST

VGBR 2- Genome-wide Association Study and Genome Prediction of Bolting Trait in Spinach
Thursday September 26, 2024 2:15pm - 2:30pm HST
Spinach (Spinacia oleracea L.) stands as a globally significant vegetable celebrated for its rich array of nutritional and health-promoting compounds. Bolting, a crucial trait in spinach cultivation across diverse seasons and regions, is heavily influenced by photoperiod sensitivity. The premature induction of bolting in spinach due to extended daylight exposure can render the plant unsuitable for market. This study aimed to conduct a comprehensive genome-wide association study (GWAS) to pinpoint single nucleotide polymorphism (SNP) markers associated with late bolting in spinach and to perform genomic prediction for this trait. GWAS was executed on a panel of 295 USDA spinach germplasm accessions, utilizing 16,563 SNPs derived from whole-genome resequencing. Various statistical models, including GLM, MLM, FarmCPU, and BLINK, were deployed in the analysis using the GAPIT 3 tool. A significant quantitative trait locus (QTL) region on chromosome 6 was identified, with three SNP markers — SOVchr6_13545609, SOVchr6_13545882, and SOVchr6_13545887 — located between 13,545,609 bp and 13,545,887 bp, demonstrating robust associations with late bolting. Additionally, the gene SOV6g004620, encoding a TTF-type domain-containing protein and situated at 13,566,721 bp to 13,567,164 bp on chromosome 6, emerged as a potential candidate for regulating bolting. Genomic prediction exhibited a high prediction ability (GA) with an r value of 0.85. The identified SNP markers and GA metrics present valuable tools for breeders to selectively cultivate late-bolting spinach plants and lines through marker-assisted selection (MAS) and genomic selection (GS), thereby facilitating enhanced spinach breeding endeavors.
Speakers
HA

Hanan Alkabkabi

University of Arkansas
NA
Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
BM

Beiquan Mou

USDA-ARS
NA
GB

Gehendra Bhattarai

University of Arkansas
HX

Haizheng Xiong

University of Arkansas
IA

Ibtisam Alatawi

University of Arkansas
NA
KC

Kenani Chiwina

University of Arkansas
NA
Thursday September 26, 2024 2:15pm - 2:30pm HST
South Pacific 3

2:15pm HST

VSF 4 - Postharvest Quality of ‘Calypso’ Blueberry After Hand and Machine Harvest
Thursday September 26, 2024 2:15pm - 2:30pm HST
The 'Calypso' blueberry has emerged as a popular variety widely planted in the Pacific Northwest. Its reputed storage quality and reasonable firmness suggest its suitability for mechanical harvesting in the fresh market using over-the-row machine harvesters. To explore its postharvest quality after both hand and machine harvest, we conducted a comprehensive study in a commercial, 7-year old 'Calypso' field in Oregon. Additionally, a drop test was employed to simulate machine harvesting for fresh market blueberries. Throughout a 4-week period of cold storage, fruit firmness generally remained stable, with occasional increases noted, while berry size remained consistent, indicating 'Calypso' maintains good storage quality. Examination of fruit internal bruise damage (IBD) by cutting berries along the equator revealed consistent levels of IBD throughout cold storage, elucidating why 'Calypso' enjoys a good shelf life. The drop test demonstrated 'Calypso's' resilience to damage from drops, with a similar pattern of fruit IBD development observed between drop-tested and machine-harvested fruits. This study highlights the slow rate of IBD development in 'Calypso' fruit as a crucial factor contributing to its success in machine harvesting for fresh market operations.
Speakers
WY

Wei Yang

North Willamette Res
Co-authors
SD

Sarah Doane

North Willamette Res
NA
Thursday September 26, 2024 2:15pm - 2:30pm HST
Nautilus 1

2:30pm HST

CE 6 - Energy Modeling and Management to Improve the Sustainability of Indoor Farming
Thursday September 26, 2024 2:30pm - 2:45pm HST
Controlled environment agriculture (CEA) is considered one of the most efficient ways of crop production. CEAs have the ability to control environmental conditions to maximize crop production. Indoor farms are considered one of the CEA systems that precisely control the environment, leading to high energy consumption in lighting, heating, cooling, and humidity control requirements. Enhancing the energy use efficiency (EUE) of indoor farms requires a better understanding of the energy characteristics of the system and crop production is needed. In this study, a steady state energy model and a machine learning based crop growth model were developed to evaluate energy-saving strategies for indoor lettuce production. The strategies included shifting photoperiod, utilizing heat tolerant crops, and adjusting air temperature settings at four different locations (Phoenix, AZ, Los Angeles, CA, Jacksonville, FL, and Boston, MA). The results showed that cultivar selection plays an important role in EUE improvement. Using high temperature settings with heat tolerant cultivars can increase the EUE of the system. However, increasing temperature setting alone does not significantly reduce energy consumption because of the increasing amount of energy needed for dehumidification. The geographical location of the indoor farm also affects energy consumption because of the different outdoor climate conditions. Boston, MA, which has the coldest outdoor air temperature, had the lowest energy consumption overall compared to the other three locations. Lastly, changing the photoperiod schedule from daytime to nighttime can reduce the electricity costs dramatically by avoiding the peak rate of electricity despite not having a significant reduction in energy consumption.
Speakers
YZ

Ying Zhang

University of Florida
Co-authors
GS

German Sandoya

University of Florida
KH

Kale Harbick

USDA-ARS
NA
NB

Nikolay Bliznyuk

University of Florida
NA
TL

Tanapol Leelertkij

University of Florida
NA
Thursday September 26, 2024 2:30pm - 2:45pm HST
Coral 1

2:30pm HST

CITR 3 - Florida Citrus Rootstock Selection 5th Edition: Artificial Intelligence Enhanced Mobile Application for Growers
Thursday September 26, 2024 2:30pm - 2:45pm HST
Florida citrus production has declined by 81% in total tonnage since 2020, mainly due to the deadly citrus greening caused by Candidatus Liberibacter asiaticus (CLas), a fastidious, phloem-limited, unculturable, gram-negative, α-proteobacterium vectored by the Asian Citrus Psyllid (ACP). Over $1.5 billion in funds have been mobilized since 2006 to overcome this disease. As an innate immune response, the infected plant deposits callose and p-protein in the phloem sieve pore, decreasing the flow of photoassimilates, leading to a rapid decline and, eventually, a plant collapse. The high cost of production has economically devastated Florida citrus growers. Using HLB tolerant rootstocks is one alternative to mitigate CLas effects, and the growers depend on the University to provide the most up-to-date recommendations. To address this, we have developed a convenient mobile application that uses artificial intelligence (AI) to assist growers in making the best rootstock selection for their groves based on horticultural traits, abiotic tolerances, and specific disease/pest incidences. The Florida Citrus Rootstock Guide Expert System 5th Edition is planned to be released by 2025 and is based on the information released in the previous editions. In addition to the release of the mobile application on all major platforms, an interactive web-based rootstock table has been updated with recent field data and newly released rootstocks. Historical and unavailable rootstocks are excluded from the selection list, increasing the incidence rate for a well-suited rootstock selection. Users can download, send, and retrieve rootstock reports on their mobile devices. The app’s design was generated from grower/user surveys to be as user-friendly as possible. The expert system is built on the ES-Builder Web application, McGoo Software, and is developed utilizing Google’s Dart programming language. The University of Florida is committed to establishing an AI-based university. The app's scalability will allow it to fully integrate into future AI projects to combat epidemics like citrus greening.
Speakers
AG

Andres Gonzalez Neira

University of Florida - IFAS - IRREC
Co-authors
FT

Flavia Tabay Zambon

University of Florida - IFAS - IRREC
JC

John Chater

University of Florida
MR

Mark Ritenour

University of Florida - IFAS - IRREC
NA
Thursday September 26, 2024 2:30pm - 2:45pm HST
South Pacific 2

2:30pm HST

HSMP 2 - Multipronged Strategies to Combat Seed-Piece and Soil-borne Diseases of Ginger
Thursday September 26, 2024 2:30pm - 2:45pm HST
Ginger (Zingiber officinale Roscoe) is esteemed for its diverse uses in flavoring beverages, enhancing cuisines and offering medicinal benefits such as aromatherapy and home remedies. Yet, its global production struggles to meet demand due to persistent seed-piece and soil-borne diseases (SSDs) caused by fungi, bacteria, oomycetes and nematodes. Lack of genetic diversity because of vegetative propagation exacerbates the situation. This study explored the efficacy of hot water treatment (HWT, 47°C for 30 minutes or 52°C for 10 minutes), Trichoderma-based biocontrol products (BPs, RootShield®, RootShield®Plus) and chitosan (1 or 5g/L in 1% HCl) alone or in combination with each other using ‘Chinese’ variety grown in a 10-lber grow-bags in a high tunnel. Fusarium oxysporum f.sp. zingiberi) was inoculated (2 X 103 conidial suspension/ml) prior to and after HWT, BPs and / or Chitosan. Results showed significantly higher mortality when seed-pieces were treated and then inoculated with pathogen before planting than vice versa. In one of the experiments, ginger plants grew significantly taller when treated chitosan (5g/L) when compared with non-treated control. Dipping seed-pieces in BPs also showed significantly higher growth and yield compared to only HWT or the non-treated control. The research contributes components that can be added towards developing integrated preventative and curative measures to mitigate SSDs. Recently, leaf spot caused by Curvularia sp. and postharvest infections by Pythium sp. and Penicillium sp. are under investigation. Scouting research plots in high tunnels and a grower’s greenhouse also revealed arthropod damages by grasshoppers, caterpillars, mites and sucking insects in protected systems.
Speakers
ZM

Zelalem Mersha

Virginia State University
Thursday September 26, 2024 2:30pm - 2:45pm HST
Kahili

2:30pm HST

NUR 2 - A 2-Dimensional Analysis of How Root Architecture and Morphology Are Influenced by Stratified Substrate Systems
Thursday September 26, 2024 2:30pm - 2:45pm HST
Soilless substrates serve an important role in both the sustainability of specialty crop production and supporting healthy containerized root growth. The requirements and tolerance of containerized roots are essentially what dictates the (i) physiochemical limitations of the substrate, (ii) how production practices are managed (i.e., quantity and quality of irrigation / fertilization), and (iii) the performance of high-quality shoot growth and development, emphasizing the importance of both substrates and roots. Nevertheless, most horticultural crop research primarily focuses on shoot growth and dismisses important root growth traits, often only reporting root biomass at study culmination or during destructive harvests. Information regarding how roots grow throughout the substrate matrix is evidently sparse. More research is needed to develop better understandings of spatial and temporal root development, such as root architecture, which describes how (and where) roots invests carbon throughout the 3-Dimentional substrate matrix. Research regarding popular engineered substrate systems, stratified substrates (i.e., layering different media atop each other), has began to dive deeper into how roots grow in time and space, where stratified-grown roots grow differently than traditionally grown (non-stratified) cropping systems. However, no research to date as explored root architecture, temporally or spatially, in stratified systems. The study herein explored root architecture in time and space using clear acrylic-based RhizoBoxes (8-L vol.). Several different types of crops (nursery- hibiscus; greenhouse- basil; representative crop- sunflower) were grown in different non-stratified and stratified substrate systems, including bark- [non-stratified: 100% unscreened bark; stratified- fine bark (< 6.3 mm) layered over coarse bark (> 6.3 mm)] and peat-based [non-stratified: 100% peat-lite (7:3); stratified: peat-lite layered over unscreened bark] substrates. Root growth was traced frequently and analyzed quantitatively for total visible root length and growing angle, and qualitatively for general shape and patterns. The results showed that stratified grown crops, across cropping systems, had a wider root distribution spreading angle, growing wider and more outward than crops grown in non-stratified systems. Moreover, stratified grown crops typically grew in the upper stratified layer longer than crops grown traditionally, growing more sequentially than continuously. In most cases, stratified-grown crops had longer visible roots growing against the acrylic glass in the upper 50% of the profile. Stratified-grown roots were often longer and finer than non-stratified grown crops. In all, this study highlights that stratified grown crops have superior root growth and development and that RhizoBoxes are a useful tool in studying root architecture in soilless substrate systems.
Speakers
avatar for Kristopher Criscione

Kristopher Criscione

LSU AgCenter Hammond Research Station
Co-authors
JF

Jeb Fields

LSU AgCenter Hammond Research Station
Thursday September 26, 2024 2:30pm - 2:45pm HST
South Pacific 4

2:30pm HST

PUBHORT/Hort Industry - Improving Military Community Reintegration: The Effects of Plant-related Jobs on Military Service Member Mental and Physical Health
Thursday September 26, 2024 2:30pm - 2:45pm HST
Military members are a unique and diverse group making up 7% of the U.S. population. After completing their military service many return home and struggle with reintegration back into civilian life due to mental and physical ailments they obtained during enlistment. One of the first steps of civilian reintegration is acquiring a job. A type of job that military members enter is in plant-related fields. Research on the passive and active interaction with plants and its benefits, has been conducted extensively. However, it is not yet known how specific jobs that require working with plants or being in nature can help improve military member health and if they have therapeutic benefits. To evaluate this, part 1 of an online survey ascertained demographics and part 2 was created based on the National Veteran’s Survey and the VR-36 which looked at participants’ physical (PCS) and mental wellness (MCS). Results show that most of the military participants (N=148) were in the 25-30 year and 40-50-year-old range, Caucasian (70.9%) males (68.9%) involved in Army (44.6%) and Marine (24.3%) branches of the military and honorably discharged or retired. Military members in plant-related jobs scored in the top 3 job categories for PCS (49.1) and MCS (45.0), while Health related jobs were top for MCS (53.6) and those retired were top for PCS (49.7). Overall, those in plant, health, and retired jobs described them as relaxing, easy, and physical. Military in rural locations also had lower MCS in comparison to those living in urban centers. The findings from this research suggest that plant-related jobs could offer military members an opportunity to improve their mental and physical health, while helping with job retention and community reintegration.
Speakers
AT

Alicia Thomas

Texas Tech University
Thursday September 26, 2024 2:30pm - 2:45pm HST
Lehua Suite

2:30pm HST

VCM 5 - Striving to stay clean: Production of sweetpotato nuclear stock used for certified seed growers in North Carolina
Thursday September 26, 2024 2:30pm - 2:45pm HST
The Micropropagation and Repository Unit (MPRU) produces, maintains and distributes meristemmed-tip culture, virus-tested, indexed, true-to-type sweetpotato nuclear plants to certified seed growers in NC. Under the certification program, seed growers use nuclear plants for production of G0 plants in greenhouses, and subsequently G1 and G2 plants and storage roots (seed) in the field. All these materials are inspected and certified by NC Crop Improvement Association, Inc. (NCCIA). The MPRU is a clean center for sweetpotato under the National Clean Plant Network (NCPN) umbrella. It works closely with the NC State sweetpotato breeding and genetics program to clean advanced selections yearly. The MPRU distributes about 90,000 nuclear plants to NC certified seed growers every year. It is estimated that about 70% of the commercial sweetpotato acreage in NC is planted annually with stocks derived from the MPRU. It is known that the accumulation and perpetuation of viruses in sweetpotato is a major constraint for production of seed and the commercial crop. The aphid-transmitted potyvirus complex is prevalent in NC and comprises Sweet potato feathery mottle virus (SPFMV), Sweet potato virus G (SPVG), Sweet potato virus C (SPVC) and Sweet potato virus 2 (SPV2). In order to evaluate the performance and quality of clean seed after it had been integrated into commercial sweetpotato operations, NCPN field trials were carried out in 2021 and 2023 with Covington and Beauregard as evaluated varieties. Because sweetpotato is vegetatively propagated, viruses and mutations can accumulate readily which can lead to cultivar decline. G1 seed was used as a reference to compare the yield and virus incidence of growers’ generation 2 (G2), generation 3 (G3) and generation 4 (G4) seed roots (grown in the growers’ seed production fields 1, 2 or 3 years following the year of clean seed production). Virus detection data suggested a low incidence of viruses (mainly SPFMV) on G1 material. Potyviruses (mainly SPVG, SPVC and SPFMV) started to be prevalent on G2 and G3 material. In the older generation evaluated (G4), all potyviruses (SPVG, SPVC, SPFMV and SPV2) were detected. In general, the prevalence of four potyviruses was associated to higher seed generations, indicating a buildup over the years on clean seed regardless of the variety. Yield data suggested a negative impact due to virus infections in Beauregard. This study will allow us to understand the impact of clean seed on the economic value of the crop to educate growers and stakeholders.
Speakers
CA

Christie Almeyda

MPRU Director, North Carolina State University
Co-authors
CY

Craig Yencho

North Carolina State University
NA
DA

Dustin Auman

North Carolina Crop Improvement Association, Inc
NA
KP

Kenneth Pecota

North Carolina State University
NA
Thursday September 26, 2024 2:30pm - 2:45pm HST
South Pacific 1

2:30pm HST

VGBR 2 - Towards the Improvement of Lettuce for Heat Tolerance Adapted to Controlled Environment Agriculture
Thursday September 26, 2024 2:30pm - 2:45pm HST
Lettuce (Lactuca sativa L.) is one of the top ten most consumed vegetables in the United States. In Controlled Environment Agriculture (CEA), lettuce is one of the most cultivated vegetables. The crop yield is severely affected by heatwaves during production. As a result of severe warmer temperatures, lettuce develops physiological disorders such as bolting and tipburn and consequently less marketability and yield. In order to reduce cooling costs and extend the growing season of lettuce crops, breeding heat-tolerant germplasm is imperative. In this research our aim was to confirm heat tolerance in lettuce identified in fields when grown in hydroponics. Initial screenings were conducted at the North Florida Research and Education Center- Suwannee Valley. One hundred and four lettuce accessions from four morphological types (Boston, Latin, leaf, and romaine) were planted in a Nutrient Film Technique (NFT) hydroponic system in a passively vented greenhouse in two experiments. Germplasm included commercial cultivars, plant introductions, legacy cultivars, and breeding lines from the University of Florida /Institute for Food and Agricultural Sciences (UF/IFAS) Lettuce Breeding Program. Data was collected on head weight and related characteristics including marketability, head height, density and width, and core length. Presence of disorders such as bolting, chlorosis and tipburn were also registered as indicators on the negative effects of warmer temperatures. Germplasm with tolerance to warmer temperatures were identified within each of the lettuce types used on this research. This germplasm had an acceptable head weight with less plants that bolted and insignificant presence of tipburn. Several of the germplasm considered heat tolerant are commercial cultivars currently used by the industry in CEA. Similarly, breeding lines from the UF/IFAS Lettuce Breeding Program showed better tolerance than commercial germplasm and are candidates for breeding and genetics studies to decipher mechanisms of heat tolerance in lettuce for this specific environment. Mapping and breeding populations will soon be developed to first study the genetics of tolerance to warmer temperatures and to select germplasm in this specific environment. While tolerant germplasm will aid to decrease cost production for CEA, additional management strategies should be optimized to decrease even further cost of production for growers.
Speakers
GS

German Sandoya Miranda

University of Florida EREC
Co-authors
RH

Robert Hochmuth

University of Florida
NA
WL

Wanda Laughlin

University of Florida
NA
Thursday September 26, 2024 2:30pm - 2:45pm HST
South Pacific 3

2:30pm HST

VSF 4 - Preliminary Findings from the Evaluation of New Cranberry Cultivars in Massachusetts
Thursday September 26, 2024 2:30pm - 2:45pm HST
Cranberry growers in Massachusetts still rely primarily on heritage cultivars, such as Howes (1843) and ‘Early Black’ (1852). The research aims to increase the profitability and sustainability of the Massachusetts cranberry industry by evaluating twelve new hybrid cultivars for improved yield, fruit quality, disease resistance, and size. The research project was initiated in March 2021 with the prorogation of the new cultivars in a greenhouse. At the same time, the renovation of a 0.75-acre cranberry bog was initiated. The renovation included stripping off the top 0.25 m of the bog and replacing it with new sand. A new irrigation and drainage system was also installed. The new cultivars were planted in June 2021 at the Cranberry Station in East Wareham, Massachusetts. The new cultivars were planted in a randomized, complete block design with four replications per cultivar and buffer zones between the plots. Standard commercial cultural practices for new plantings regarding irrigation, fertilization, pest control, and canopy management were followed. Fruit was removed from the vines to allow maximum resource allocation for canopy growth in 2022, and the first fruit harvest was in 2023. Yield was measured by picking all fruit within a 0.09 m 2 quadrat. The fruit samples were then sieved through an 8-mm opening to remove undersized berries; the remaining berries represented the yield of marketable berries. Additional samples (≈500 g) were collected from each treatment replication for fruit quality analysis. Fruit color was measured using total anthocyanin content (TAcy). Regarding yield, Haines® (353 barrels/acre), Welker™ (287 barrels/acre), and Crimson King (243 barrels/acre) were the most productive, while Vassana® (112 barrels/acre) and HyRed® (117 barrels/acre) performed poorly, with the other cultivars in the mid-range. Scarlet Knight® (81 TAcy), HyRed® (65 TAcy), and Midnight 8 (58 TAcy) had the best fruit color, while Badger (16 TAcy), Granite Red (22 TAcy), Sundance (24 TAcy), and Pilgrim King (26 TAcy) had poor fruit color. The highest fruit rot incidence was observed in HyRed® (37%), Welker™ (52%), and Vassana® (63%), while Granite Red (11%), Mullica Queen® (13%), Badger (18%), and Sundance® (19%) had the lowest incidence. The fruit size measured as fruit diameter was largest in Badger (20.3 mm), Granite Red (20.3 mm), Crimson King (19.8 mm), and Haines® (19.5 mm). In conclusion, first-year harvest data showed differences in the performance of the cultivars under MA growing conditions. Additional data from multiple years are still needed to provide growers with recommendations.
Speakers
GM

Giverson Mupambi

University of Massachusetts Amherst
Co-authors
HS

Hilary Sandler

University of Massachusetts Amherst
NA
LU

Leela Uppala

University of Massachusetts Amherst
NA
PJ

Peter Jeranyama

University of Massachusetts Amherst
NA
Thursday September 26, 2024 2:30pm - 2:45pm HST
Nautilus 1

2:30pm HST

Workshop: Climate Impact on Tree Nut Crops
Thursday September 26, 2024 2:30pm - 4:30pm HST
This workshop will explore topics related to climate change impacts on temperate tree nut crops, including drought, salinity, freeze issues, and other environmental stressors. Additionally, participants will be given the opportunity to discuss relevance of topics to their specific commodity and share insights and suggestions with fellow researchers.

In this workshop we will be bringing in experts in pistachio and pecan cultivation to share their cutting-edge research and insights into mitigating the challenges posed by climate change. These esteemed speakers, who have dedicated their careers to understanding and addressing these issues, will provide valuable insight to workshop attendees and jumpstart discussion on this topic within groups. Attendees will have the opportunity to discuss relevant issues of climate change on their crop within small groups before bringing ideas to the entire group.

The impact of climate change on tree nut crops is likely to be significant, given expected decreases in chilling, increased droughts, and fluctuations in winter temperatures leading to decreases in production if mitigation measures are not implemented.

In this workshop, we seek to foster fruitful discussion among researchers working with tree nuts and other orchard crops likely to be impacted by climate change in order to brainstorm solutions and targets for future research in this topic area.

Coordinator(s)
  • Lu Zhang, Oklahoma State University, Stillwater, OK, United States
  • David Hlubik, Rutgers University, United States
  • Phoebe Gordon, University of California Cooperative Extension, Madera, CA 93638, Madera County, United States
Speaker/Participant(s)
  • Louise Ferguson, University of California Davis, Extension Specialist, Davis, California, United States
    Climate Impact on Tree Nut Crops - Pistachio Salinity (30 mins)
    Summary: Dr. Louise Ferguson is an Extension Specialist at University of California Davis with several decades of experience in pistachio and other orchard crops and will be speaking on pistachio salinity.
  • Richard Heerema, New Mexico State University, Extension Specialist, Las Cruces, New Mexico, United States
    Climate Impact on Tree Nut Crops - Drought in Pecan (30 mins)
    Summary: Dr. Richard Heerema is an Extension Specialist at New Mexico State University with a focus on pecans and will be speaking on drought in pecan.
  • Xinwang Wang, USDA ARS, College Station, TX, United States
    Climate Impact on Tree Nut Crops - Pecan Breeding Associated with Climate Change (30 mins)
    Summary: Dr. Xinwang Wang is a Research Geneticist for USDA ARS in College Station, TX and will be discussing challenges in pecan breeding associated with climate change.



Moderator
LZ

Lu Zhang

Oklahoma State University
Speakers
Thursday September 26, 2024 2:30pm - 4:30pm HST
Coral 2

2:45pm HST

CE 6 - Increasing Circularity in Controlled Environment Agriculture using Anaerobic Digester Effluent as an Organic Fertilizer
Thursday September 26, 2024 2:45pm - 3:00pm HST
As global population and stress on our natural resources increases, we need to rethink how/where we produce food with emphasis on recycling resources such as carbon, water, and nutrients. Controlled environment agriculture (CEA) is gaining increasing attention due to its potential for improving resource use efficiency compared to traditional field-based agriculture. This project investigated a novel approach for treating hydroponics irrigation water and recovering nutrients from vegetable waste for reuse in CEA systems. An integrated anaerobic/aerobic biological treatment process was investigated. Anaerobic digester effluent was nitrified via an aerobic membrane bioreactor process to produce a liquid organic fertilizer supplement (nADE). The nADE was evaluated as a nutrient source for indoor hydroponic and greenhouse soilless drip-irrigation lettuce cultivation. Lettuce yield, tissue nutrient content, water quality, and nutrient uptake efficiency were compared between the nADE treatment and a commercial fertilizer control for each CEA system. The lettuce grown on nADE demonstrated similar or higher yields, more leaves, and elevated tissue nutrient content than the control. The nADE media improved N and P uptake efficiency in the drip-irrigation system but decreased K, Ca, and Mg uptake efficiency, possibly from the over-application of these nutrients. Further research is needed to optimize the integrated treatment system as well as nADE dosing. The study demonstrates a circular bioeconomy approach to decrease dependency on inorganic fertilizers while benefiting crop yield and quality.
Speakers
AM

Ana Martin Ryals

University of Florida
Co-authors
HB

Haimanote Bayabil

University of Florida
NA
KV

Kelsey Vought

University of Florida
NA
Thursday September 26, 2024 2:45pm - 3:00pm HST
Coral 1

2:45pm HST

CITR 3 - Australian Microcitrus-Derived Hybrids: Field Performance in Florida Under HLB Endemic Conditions
Thursday September 26, 2024 2:45pm - 3:00pm HST
At the Queensland Department of Agriculture and Fisheries, the breeding program used native Australian citrus species (C. australasica, C. australis, C. garrawayi, and C. inodora), collectively referred to as Microcitrus, and cultivated Citrus. Commencing in 1998, this program aimed to introduce desirable Microcitrus traits into cultivated citrus, resulting in hybrids with pedigrees ranging from 12.5% to 100% Microcitrus. Previous studies suggest that specific Microcitrus accessions may exhibit resistance to huanglongbing (HLB), a disease associated with Candidatus Liberibacter asiaticus (CLas). To assess this resistance, we conducted tests on these Microcitrus-derived seedlings in a Florida field site where HLB and its vector, the Asian Citrus Psyllid (Diaphorina citri; ACP), are prevalent. Seeds were received in August 2015 and grown into field-ready seedling trees at the USHRL greenhouse. In August 2018, these trees were planted in a randomized layout at the Fort Pierce USDA grove, comprising 53 Microcitrus-derived populations alongside grafted Clementine and Hamlin standards. During 2020 and 2021, a subset of these plants underwent 24 assessments for ACP colonization, focusing on periods of abundant citrus flush and active D. citri presence. Data collected included observations of eggs, nymphs, and 5th instars, indicating D. citri's ability to complete development on the plant. Statistical analysis assessed variations in egg and nymph abundances concerning scion and date, revealing differing nymph counts across dates and scion types, with Hamlin and Arrufatina X 09Q048 displaying the highest nymph counts. Additionally, all trees were evaluated for CLas levels in October 2021 and no significant differences were found. The study encompassed seedling development, field planting, and standard citrus production practices, with minimal pesticide usage to determine the tolerance of Australian-derived hybrids to HLB.
Speakers Co-authors
ES

Ed Stover

Retired (USDA,ARS)
NA
FT

Flavia Tabay Zambon

University of Florida - IFAS - IRREC
Thursday September 26, 2024 2:45pm - 3:00pm HST
South Pacific 2

2:45pm HST

HSMP 2 - Seed emergence of Fagonia indica, a plant with potential chemistry active against breast cancer.
Thursday September 26, 2024 2:45pm - 3:00pm HST
Phytochemicals from the genus, Fagonia, have potential beneficial effects on human health. Fagonia indica is a Pakistani traditional herbal medicine thought to be useful for the prevention and treatment of breast cancer Acid-hydrolyzed extracts of Fagonia indica have bioactivity on breast cancer MCF-7 cells in vitro. Horticultural production of Fagonia indica is largely undeveloped. Seeds planted without special treatment show poor emergence and come up slowly over many weeks. Seed treatments with vernalization, scarification, gibberellic acid soaking and their interactions were tested. Seed were treated and planted into mulch. Less than 1 percent of untreated seed emerged within 3 weeks of planting. Both seed scarification and gibberellic acid greatly enhanced emergence. Vernalization had a small effect on total emergence but did increase seedling emergence during the first two weeks following planting, Scarification and gibberellic acid could be refined by making variations in these practices.
Speakers
CS

Clinton Shock

Scientific Ecological Services
Thursday September 26, 2024 2:45pm - 3:00pm HST
Kahili

2:45pm HST

NUR 2 - Predicted Drought Tolerance of Cephalanthus occidentalis L. for Use in Managed Landscapes
Thursday September 26, 2024 2:45pm - 3:00pm HST
Buttonbush (Cephalanthus occidentalis) is a valuable landscape shrub revered for its prominent white, globe-shaped blooms which can later develop into brilliant red aggregate fruits. This North American native shrub occurs almost exclusively in riparian habitats, typically in standing water in the wild, but it is curiously adaptable to a range of landscape conditions in cultivation. Because this species appears to perform well when grown using average soil-moisture conditions, we questioned where the limits of drought tolerance occur for this riparian-adapted species. The objective of this study was to evaluate USDA-GRIN germplasm of buttonbush to compare unique provenances representing different regions of the native range of the taxon to generate a relative scale of predicted drought tolerance for the species. Utilizing vapor pressure osmometry, this study examined seasonal osmotic adjustment and predicted leaf water potential at the turgor loss point (ᴪpo) among ten Cephalanthus occidentalis populations grown at the Morton Arboretum in Lisle, Illinois. All populations evaluated demonstrated a minor ability to osmotically adjust (Δᴪ𝝿100) throughout the growing season. NA 79917 exhibited the most osmotic adjustment (-0.22 MPa) whereas NA 61271 exhibited the least (-0.08 MPa). Estimated spring ᴪpo and summer ᴪpo across populations was -1.75 MPa and -1.91 MPa, respectively. NA 79705 exhibited the highest ᴪpo in both spring (-1.56 MPa) and summer (-1.68 MPa). NA 82190 exhibited the lowest ᴪpo in spring (-1.92 MPa ), whereas NA 73814 exhibited the lowest in summer (-2.17 MPa). These data indicate that drought tolerance in buttonbush varies across populations, suggesting that this trait can be improved in landscape selections through selective breeding efforts.
Speakers
avatar for John Larsen

John Larsen

Graduate Student, University of Minnesota
John works with winter hardy landscape plants, with a special emphasis on Salix pellita (Satiny Willow). A major interest of John's is looking at the horticultural potential of certain native flora, hoping this could lead to new means of conservation for Minnesota's threatened sp... Read More →
Co-authors
BM

Brandon Miller

University of Minnesota
KS

Kim Shearer

The Morton Arboretum
NA
Thursday September 26, 2024 2:45pm - 3:00pm HST
South Pacific 4

2:45pm HST

PUBHORT/Hort Industry - Evaluating the Impacts of Climate Change on Urban Tree Performance and Survival
Thursday September 26, 2024 2:45pm - 3:00pm HST
Climate change is expected to lead to the increased frequency and intensity of natural disasters, which will adversely affect urban tree populations. As a result of rising surface temperatures, USDA Hardiness Zones are projected to shift northward. Healthy urban trees can offer benefits which may offset some of the effects of warming. Therefore, species adaptability to urban conditions needs to be considered, and we need to understand the predicted impacts of warming better in order to design and plant more resilient urban forests. Thus, in the Fall of 2022, protocols began developing to evaluate the following areas of concern: 1: Identify underutilized tree species that might perform well in future climates. A state-wide survey was distributed to green industry professionals to guide species selection for field trials across three hardiness zones in Florida (8b, 9a, and 10b). 2: Analyze the variability of commonly used irrigation technologies on tree establishment. The project compares two commonly used irrigation bags (i.e., TreeDiaper and Treegator) to hand watering to determine labor inputs, time to establishment, and overall tree performance. 3: Determine the effects of increased temperatures on tree species commonly planted in Florida. Temperature-controlled greenhouse experiments will be used to determine the heat tolerance of 6 tree species based on future climates. 4: Analyze parking lot plantings and evaluate the impact of the mitigation of the urban heat island effect. Several randomly selected parking lots in Florida will be looked at to determine their suitability for planting based on the adverse growing conditions associated with urban heat islands. The above studies offer a proactive approach to better understanding the potential effects of warming and provide practical solutions to minimize the impact.
Speakers
avatar for Teagan Young

Teagan Young

PhD Research Assistant, University of Florida
Hi there! I come from the lovely town of Kalamazoo, MI, where my love for taking care of nature through horticulture first took root. In 2019, I made my way down to Gainesville, FL, enticed by the opportunity to join the respected University of Florida's Environmental Horticulture... Read More →
Co-authors
GH

Gail Hansen

University of Florida
NA
LW

Laura Warner

University of Florida
NA
RK

Ryan Klein

University of Florida
NA
SW

sandra wilson

University of Florida
Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral... Read More →
Thursday September 26, 2024 2:45pm - 3:00pm HST
Lehua Suite

2:45pm HST

VCM 5 - Effects on yield, quality, sugar content and soil health indicators of foliar and soil applied Chlorella vulgaris in ‘Beauregard’ sweetpotato (Ipomoea batatas [L.] Lam).
Thursday September 26, 2024 2:45pm - 3:00pm HST
Commercial sweet potato production has seen a recent surge in both fresh market and processing acreage in South Carolina. Producing quality conventionally and organically grown sweetpotatoes is a challenge in South Carolina due to numerous biotic and abiotic factors. One of the most important deciding factors on sweetpotato yield is germplasm and fertility. In this study we examined effects on yield and quality of foliar and soil applied Chlorella vulgaris (CV) in ‘Beauregard’ sweetpotato (Ipomoea batatas [L.] Lam). Chlorella vulgaris (EnSoil Algae, Enlightened Soil Corp) is marketed under the USDA/APHIS category of soil amendments and Plant Growth Enhancers (PGE). This study was conducted in 2022-2023 in a randomized complete block full factorial design with 4 replications and a total of 17 treatments with a product rate of 250ml/Ac, including the following: 1) Unfertilized Control, 2) 100 % Preplant Granular Fert. (PGF), 3) Soil Algae Application (SAA), 4) Foliar Algae Application (FAA), 5) 100% PGF SAA, 5) 100% PGF SAA, 6) 100% PGF FAA, 7) 100% PGF SAA FAA, 8) SAA FAA, 9) 25% PGF SAA 75% Drip Irrigation Fert.(DIF), 10) 25% PGF FAA 75% DIF, 11) 25% PGF SAA FAA 75% DIF, 12) 25% PGF SAA, 13) 25% PGF FAA, 14) 25% PGF SAA FAA, 15) 25% PGF 75% DIF, 16) 75% DIF, 17) 25% PGF. Results were mixed over time with 2022 being a better growing year. In 2022, USDA grade Jumbo roots were 10% numerically greater in SAA treated plots, than 25% PGF SAA 75% Drip Irrigation Fert. (DIF) and 9% over SAA and FAA. In 2023 there were similar trends, with USDA grade Number
Speakers
BW

Brian Ward

Clemson University CREC
Co-authors
KA

Karin Albornoz

Clemson University
NA
MH

Matt Horry

Clemson University
NA
PW

Phillip Wadl

USDA, ARS, U.S. Vegetable Laboratory
Thursday September 26, 2024 2:45pm - 3:00pm HST
South Pacific 1

2:45pm HST

VGBR 2 - Root Phenotyping in Chile Pepper: Key Steps and Challenges with the RhizoVision Explorer
Thursday September 26, 2024 2:45pm - 3:00pm HST
Genetic studies of root architecture provide valuable insight into the overall yield potential of chile pepper (Capsicum annuum L.) under various biotic and abiotic conditions. Phytophthora root rot , caused by soil born pathogen Phytophthora capsici, is one of the most destructive diseases of chile pepper that incur huge losses under severe infection. Rotting of the roots and crown are the primary symptoms with lesions on stem, wilting, and necrosis leading to the plant death. RhizoVision Explorer is a high throughput phenotyping tool that facilitates precise and in-depth phenotyping of root architecture. In this study, four chile pepper cultivars were planted in three replications under greenhouse conditions. A virulent isolate ‘6347’ was used to inoculate the cultivars. At maturity, shoots were removed, and roots were thoroughly washed to prepare them for scanning. A flatbed scanner was used where a transparent plastic flat allowing roots to be submerged in the water was set up to proceed with scanning and analysis using the RhizoVision Explorer. Analysis of variance (ANOVA) demonstrated significant differences between the treated and control groups coupled with strong positive correlation (r > 0.90; P < 0.001) for maximum number of roots (MNR), number of root tips (NRT), total root length (TRL), depth (DPT), maximum width (MAXW), and width-to-depth ratio (WDR). Preliminary results provided insights into root architecture under P. capsici infection and the optimization of key procedures such as root washing and scanning. Overall, the efficiency of root phenotyping using the RhizoVision Explorer under pathogen infection could be improved by modifying specific steps related to the washing and processing of chile pepper samples. Keywords: High throughput phenotyping, Phytophthora blight, root architecture
Speakers
EK

Ehtisham Khokhar

New Mexico State University (NMSU)
Co-authors
DN

Dennis Nicuh Lozada

New Mexico State University
Thursday September 26, 2024 2:45pm - 3:00pm HST
South Pacific 3

2:59pm HST

Propagation (PROP)
Thursday September 26, 2024 2:59pm - 3:40pm HST
K-IBA Promotes Adventitious Rooting of Bog Birch Stem Cuttings - Jessica Hutchinson
Propagating Pomegranate Through Hardwood and Softwood Cuttings - PRAKRITI NEPAL
Identifying Patterns of Clone Degeneration to Improve Diagnostics - Thomas Gradziel
Evaluating Leaf Cutting Success for Achimenes Propagation - Chad Miller
Moderator
CT

Chad T. Miller

Assistant Professor; Department of Horticulture and Landscape, Colorado State University
Thursday September 26, 2024 2:59pm - 3:40pm HST
Nautilus 1

3:00pm HST

PROP - K-IBA Promotes Adventitious Rooting of Bog Birch Stem Cuttings
Thursday September 26, 2024 3:00pm - 3:10pm HST
Native ornamental plants, which are growing in demand in the U.S. horticulture industry, may promote biodiversity and wildlife habitat, and improve landscape resilience. To succeed in the horticulture industry, novel introductions must be aesthetically pleasing and amenable to commercial propagation and production. Bog birch (Betula pumila) is a shrub native to the United States with pubescent, ovate leaves with rounded margins that have tones of red, orange, and burgundy in autumn. In addition, young pubescent stems are brown to reddish-brown and become deep in color with a glossy finish at maturity. These qualities would make bog birch attractive within managed landscapes. We investigated the effects of auxin concentration and wounding during propagation of bog birch by softwood stem cuttings under intermittent mist. Cuttings collected in late July in northern Maine and treated with the potassium salt of indole-3-butyric acid (K-IBA) in solutions of 1,000 to 5,000 mg⋅L-1 produced greater root counts and root ratings, and longer root lengths, than cuttings treated with water alone. Cambial wounding increased root counts modestly, but was unnecessary to produce quality clones. Nearly 75% of all cuttings produced roots rated 3 or higher, the threshold at which they are transplantable. Only low concentrations of K-IBA are needed to produce root systems that meet this threshold, as transplantability increased from 55% in cuttings treated with water to 73% when 1000 mg⋅L-1 K-IBA was applied. During one season in
Speakers
JH

Jessica Hutchinson

University of Maine
Co-authors
BP

Bryan Peterson

University of Maine
Thursday September 26, 2024 3:00pm - 3:10pm HST
Nautilus 1

3:00pm HST

CE 6 - Utilizing Deep Learning for Hydroponic NFT Channel Spacing Optimization
Thursday September 26, 2024 3:00pm - 3:15pm HST
In controlled environment agriculture (CEA), maintaining effective plant spacing throughout the crop growth cycle is crucial for efficient resource (light, water, space, and nutrients) utilization to achieve optimal crop yield and quality. Overcrowded or overlapping plant leaves could cause inefficient light exposure to plants/parts of plants, negatively affecting their growth. Additionally, reduced airflow makes overcrowded plants prone to diseases and foliage damage. Meanwhile, sparse plant spacing could result in inefficient space and light utilization. Traditional plant spacing adjustment relies on expert knowledge and manual labor, which is time-consuming, labor-intensive, and costly. Computer vision-based automatic plant space adjustment could help with data-driven decision-making and reduce labor dependency. This study aims to develop a deep learning-based computer vision approach to estimate the effective plant spacing by extracting the morphological characteristics of plants and NFT (nutrient film technique) channels during different plant growth stages. A total of 576 lettuce plants were grown in an NFT channel-based hydroponics system in a controlled environment. Then, RGB-D information of these plants and NFT channels was collected each day for three weeks from planting to harvesting. Then, CNN (convolutional neural network) was employed to extract the plant and NFT channel feature information. Then, the spatial pyramid pooling approach was used to encode and decode the contextual information and segment the plants and NFT channels. This approach helped to achieve an F1-score of 0.90 on the test dataset to estimate space between plants and NFT channels. These results show the potential of the proposed approach for automated plant space adjustment for efficient resource utilization.
Speakers
Thursday September 26, 2024 3:00pm - 3:15pm HST
Coral 1

3:00pm HST

CITR 3 - The Citrus Genome Database: A Resource for Citrus Research and Crop Improvement
Thursday September 26, 2024 3:00pm - 3:15pm HST
The Citrus Genome Database (CGD, www.citrusgenomedb.org) is a crop community database tailored for citrus researchers and breeders. CGD includes the Breeding Information Management System (BIMS) for both private breeding program management and publicly available phenotype and genotype data. Genetic data include genetic markers, maps, QTL, and GWAS curated from published and integrated with associated data in the database. The data is accessible via several search interfaces. Genetic maps can be viewed through the MapViewer tool, that also visualizes gene and genome data where available. CGD has over 40 genomes of Citrus and other genera in the Rutaceae family. For plant genomes, additional functional annotation and synteny analyses are conducted and made available to search. The genomes can be viewed in JBrowse, sequences searched using BLAST, genome synteny viewed with Synteny Viewer, and metabolic pathways for representative genomes can be viewed and users can overlay -omics data in CitrusCyc. Expression data associated with genes or mRNA of genomes in CGD are also available to view in the Expression Heatmap tool and on the feature page for the corresponding gene/mRNA. Ten bacterial genomes from Ca. Liberibacter and Liberibacter species are also available to search in the database, view in JBrowse, and search the sequences using BLAST. Researchers can also prepare and submit published data to the database using Excel based templates.
Speakers
JH

Jodi Humann

Washington State University
Co-authors
CH

Chun Huai Cheng

Washington State University
NA
DM

Dorrie Main

Washington State University
FG

Fred Gmitter

University of Florida
NA
KB

Katheryn Buble

Washington State University
NA
PZ

Ping Zheng

Washington State University
NA
RT

Ronald Tapia

University of Florida
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
Thursday September 26, 2024 3:00pm - 3:15pm HST
South Pacific 2

3:00pm HST

HSMP 2 - Impact of Polyploid Induction on Apigenin Production in Parsley
Thursday September 26, 2024 3:00pm - 3:15pm HST
Apigenin, an anticancer secondary metabolite, is produced in fruits, vegetables, and herbs, and has been used to prevent patient resistance to cancer treatments. Petroselinum crispum (parsley) is one of the highest natural producers of apigenin. Three parsley cultivars, ‘Darki’, ‘Giant of Italy’, and ‘Wega’, were trialed in an indoor vertical hydroponic system to determine biomass production and apigenin accumulation. The cultivar ‘Giant of Italy’ was selected as the superior cultivar with 0.16 mg apigenin accumulated in each plant and significantly higher biomass than the other cultivars. A viable strategy for increasing secondary metabolite production in plants is through polyploid induction. Although polyploid induction has not previously been used to increase apigenin, it has been used to increase production of other secondary metabolites including quercetin and kaempferol. ‘Giant of Italy’, which has been reported as 2n = 2x = 22, was induced to form tetraploid tissue by treating seeds with an antimitotic agent. Seed germination decreased with increasing treatment concentration and the surviving seeds were grown to maturity in a greenhouse. New leaf tissue was harvested for analysis, and tetraploid cells were confirmed using flow cytometry. Polyploid induction of ‘Giant of Italy’ in this study suggests potential for elevated apigenin production.
Speakers
RM

Rebekah Maynard

University of Georgia
Co-authors
JS

Joonhyuk Suh

The University of Georgia
NA
LL

Leonardo Lombardini

The University of Georgia
NA
SO

Samuel Ogundipe

The University of Georgia
NA
Thursday September 26, 2024 3:00pm - 3:15pm HST
Kahili

3:00pm HST

NUR 2 - Comparative microbial diversity analysis and isolation of plant growth-promoting rhizobacteria from roundleaf buffaloberry (Shepherdia rotudifolia)
Thursday September 26, 2024 3:00pm - 3:15pm HST
The world is haunted by climate change and global warming, posing critical challenges to plant health and productivity. Hence, it is now imperative to think about ecosystem resilience and conservation. Microbiomes from extreme environments with plant growth-promoting and stress-relieving properties can be used as inoculum for growing plants during stress. Hence, our study aims to explore the root and soil microbiome of native and hardy Shepherdia species available in Utah, USA. The native Shepherdia species, S. rotudifolia was selected for the study. We compared the microbial diversity of S. rotudifolia from three different locations in Utah. The plants' bulk soil, rhizosphere, and root were collected for the study from Torrey, Colorado City, and Cannonville in Utah and brought to the Utah State University, Logan, for further processing. DNA extraction was done from all the samples and sequenced for 16S rRNA region. The bulk soil of roundleaf buffaloberry from Torrey is highest in organic matter, while that from Colorado City is highest in salinity but lowest in NPK and most micro-nutrients. Bulk soil and rhizosphere bacterial alpha diversity differ significantly (p=0.05) among the locations of roundleaf buffaloberry; however, there is no difference in root endosphere alpha diversity among the locations. The bacterial community composition of roundleaf buffaloberry from Torrey is significantly different from the other two locations. Proteobacteria and Actinobacteriota are the dominant phyla in the bulk soil and rhizosphere of roundleaf buffaloberry from all three locations; however, Actinobacteriota dominates in root in all three locations. The genus composition of bulk soil, rhizosphere, and root of roundleaf buffaloberry is very diverse among the three locations. Frankia, the well-known nitrogen-fixing bacteria, is prevalent in the root samples of S. rotundifolia from Cannonville and has lesser abundance in the other two locations. Fifty-seven bacteria were isolated from the rhizosphere of the S. rotudifolia on different nutrient media. These isolates are being tested for eight plant growth-promoting traits, such as the production of indole acetic acid, siderophore, catalase, protease, ACC deaminase activity, nitrogen fixation, phosphate solubilization, and sulfur-oxidizing activity
Speakers
AK

Amita Kaundal

Utahs State University
Thursday September 26, 2024 3:00pm - 3:15pm HST
South Pacific 4

3:00pm HST

PUBHORT/Hort Industry - Managing Drift in Vegetable Operations: Extension Risk Management Herbicide Workshops
Thursday September 26, 2024 3:00pm - 3:15pm HST
Herbicide drift from the site of application into non-target areas can be devastating to the environment and to neighbor operations. Crop injury will occur from drift and improper management of herbicides within an operation. Environmental conditions, applicator off-label usage and accidents are often the cause of herbicide drift. Prevention and communication are the most important strategies in managing off target application of herbicides. Two workshops were held in Louisiana. Vegetable producers, Department of Agriculture inspectors, county agents, and crop producers were invited to both workshops. Pre and post tests were given to all participants to measure general herbicide application and rule knowledge. The workshops consisted of fields showcasing tomatoes and squash with 4 herbicides sprayed on them to showcase what drift looks like. Control (non-sprayed plants) were also in the field. All plots were replicated but only half labeled. The participants learned what the symptoms looked like, then worked in teams to identify the non-labeled plots. Participants also learned how to properly clean tanks and nozzles, as well as listened to speakers about the economic loss from off target herbicide drift, and rules and regulations from Louisiana Department of Ag and Forestry specialists. 77% of the participants could identify round up damage by the end of the workshop, whereas only 40% could identify 2, 4D damage. All participants increased knowledge in tank cleaning and cross contamination prevention by the end of the workshop. and All participants gained knowledge in the documentation of crop loss economic questions at the end of the workshops.
Speakers
KF

Kathryn Fontenot

LSU AgCenter
Co-authors
AH

Alessandro Holzapfel

Louisiana State University Agricultural Center
MB

Maria Bampasidou

LSU AgCenter
NA
RS

Ronald Strahan

LSU AgCenter
NA
Thursday September 26, 2024 3:00pm - 3:15pm HST
Lehua Suite

3:00pm HST

VCM 5 - The Effect of Potassium Fertilization on Potato Tuber Nutrition in the Columbia Basin of Oregon
Thursday September 26, 2024 3:00pm - 3:15pm HST
Potato (Solanum tuberosum L.) crops require a high amount of potassium (K) to achieve the ideal yield and quality. However, the effect of K fertilization on potato tuber nutritional value is largely unknown. Based on the tubers from two-year field trials on a Quincy loamy fine sand soil in the Columbia Basin of Oregon, we evaluated yield, specific gravity, nutritional contents (i.e., ascorbic acid, tyrosine, chlorogenic acid, tryptophan, phenylalanine), and nutrient contents (nitrogen [N], phosphorus [P], K, and sulfur [S]) of three potato varieties (Clearwater Russet, Russet Burbank, and Umatilla Russet) under three K rates (0, 448, and 897 kg ha-1). Our results showed that the K application increased the yield of >170 g tubers but had no considerable effect on the total tuber yield. The application of K tended to decrease specific gravity regardless of varieties and years. Russet Burbank had the lowest specific gravity while Clearwater Russet had the highest one. Most of the nutritional contents were higher in 2020 than in 2021. Russet Burbank generally had the highest nutritional contents except for ascorbic acid compared to two other varieties. The application of K generally did not affect tuber nutritional contents but reduced the amounts of tyrosine in Clearwater Russet and Umatilla Russet in 2020. Fertilization of K resulted in an enhanced K content in the tuber, with the highest K application rate exhibiting a 35% increase in K compared to the control. However, it did not have any discernible effects on N, P, and S contents in the tubers. The tuber P and S were lower in Russet Burbank than other varieties. In general, there is no strong relationship between K fertilization and tuber nutritional contents.
Speakers
RQ

ruijun qin

OSU-HAREC
Co-authors
AG

Aymeric Goyer

Oregon State University
NA
ST

Shahram Torabian

Virginia State University
NA
Thursday September 26, 2024 3:00pm - 3:15pm HST
South Pacific 1

3:00pm HST

VGBR 2 - Towards Mechanical Harvest: Leveraging Genomic Selection to Increase Fruit Firmness in Fresh Market Tomato
Thursday September 26, 2024 3:00pm - 3:15pm HST
Mechanical harvesting could help address the challenges related to the cost and availability of labor experienced by Florida’s fresh market tomato industry. However, tomato fruit are very susceptible to bruising, which is likely to be exacerbated by mechanical harvest. Previous studies have found that fruit firmness plays an important role in cultivar resistance against internal bruising. The UF/IFAS tomato breeding program has worked to develop tomato lines with traits important for mechanical harvest, including a compact growth habit (CGH) and increased fruit firmness. To investigate the inheritance and genetic architecture of fruit firmness among CGH lines in the program, bi-parental populations were developed from firm and soft inbred parents. Genome wide association analysis identified multiple significant fruit firmness quantitative trait loci (QTLs) with minor effects, underscoring the quantitative nature of the fruit firmness trait among the population studied. The dissection of fruit firmness variance components revealed mostly additive variance components. Genomic selection (GS) models were successfully trained to predict fruit firmness, demonstrating the viability of GS integration into the UF Tomato Breeding program. Significant gains in prediction accuracy and computational efficiency were achieved through model parameters fine-tuning such as training population size and marker density optimization, and modeling of significant QTLs as fixed effects. This work demonstrates that significant fruit firmness variability exists in the UF/IFAS tomato breeding program germplasm and can be selected for to develop firm-fruited CGH tomatoes intended for mechanical harvest. Furthermore, the successful training of fruit firmness GS models will aid in the efficient development of CGH fresh market tomato cultivars intended for mechanical harvest. The training of multi-trait and multi-environment genomic selection models to leverage the variance-covariance information between traits and between testing environments may result in increased prediction accuracies and needs to be explored.
Speakers
JC

Jessica Chitwood-Brown

University of Florida
Co-authors
LG

Leonard Gaspar

University of Florida IFAS GCREC
NA
SH

Samuel Hutton

University of Florida IFAS GCREC
NA
Thursday September 26, 2024 3:00pm - 3:15pm HST
South Pacific 3

3:00pm HST

Teaching Methods (TCHG) Interest Group Meeting
Thursday September 26, 2024 3:00pm - 4:00pm HST
Moderator
KO

Kathryn Orvis

Professor, Purdue Univ
Thursday September 26, 2024 3:00pm - 4:00pm HST
Sea Pearl 4

3:10pm HST

PROP - Propagating Pomegranate Through Hardwood and Softwood Cuttings
Thursday September 26, 2024 3:10pm - 3:20pm HST
Pomegranate (Punica granatum) is a fruit-bearing deciduous shrub or small tree known for its nutritious and medicinal value. Its global demand is high due to rich antioxidant content, health benefits, and culinary versatility. However, the expansion of pomegranate cultivation face challenges due to the need for efficient propagation techniques that can produce high-quality plant material to meet commercial and agricultural demands. The propagation of pomegranate using cuttings is considered an easy and cost-effective method. Hardwood and softwood cuttings were treated with 3000 mg/ L indole-3-butyric acid (Hormodin® 2) and stuck in a rooting medium consisting of perlite and peat moss (4:1, v:v). Hardwood cuttings of 21 pomegranate cultivars, including ‘Al-Sirin-Nar’, ‘Angel Red’, ‘Apseronski’, ‘Arturo Ivey’, ‘Ben Ivey’, ‘Carolina Vernum’, ‘Chiva’, ‘DeAnda’, ‘Early Wonderful’, ‘Kandahar’, ‘Kazake’, ‘Kunduzski’, ‘Larry Ceballos І’, ‘ML’, ‘Mollar’, ‘Purple Heart’, ‘Russian 8’, ‘Salavatski’, ‘Spanish Sweet’, ‘Surh-Anor’ and ‘Wonderful’ were propagated in 2014, 2016, 2018, and 2023. In addition, softwood cuttings of 23 cultivars, which included ‘Al-Sirin-Nar’, ‘Ambrosia’, ‘Apseronski’, ‘Ariana’, ‘Azadi’, ‘Cranberry’, ‘Desertnyi’, ‘Eversweet’, ‘Golden Globe’, ‘Green Globe’, ‘Haku Batan’, ‘Loffani’, ‘Medovji Vahsha’, ‘Molla Nepes’, ‘Palermo’, ‘Parfianka’, ‘Phoenicia’, ‘Purple Heart’, ‘Salavatski’, ‘Sirenevyi’, ‘Surh-Anor’, ‘Vkusnyi’, and ‘Wonderful’ were propagated in 2022. The rooting percentage of hardwood cuttings was higher in ‘AL-Sirin-Nar’, ‘Salavatski’ and ‘Surh-Anor’, whereas ‘DeAnda’ and ‘Early Wonderful’ showed lower rates compared with other cultivars based on cluster analysis. For softwood cuttings, the rooting percentage did not display significant differences across cultivars, however, the number of roots were significantly higher in ‘Cranberry’, ‘Eversweet’, ‘Surh-Anor’ and ‘Wonderful’ compared with ‘Ambrosia’ and ‘Golden Globe’. Further research is needed to identify the most effective propagation technique for pomegranate production.
Speakers
PN

PRAKRITI NEPAL

Utah State Univeristy
Co-authors
AP

Asmita Paudel

Utah State University
NA
BS

Benjamin Scow

Utah State University
NA
YS

Youping Sun

Utah State Univeristy
ZW

Zirui Wang

Utah State University
Thursday September 26, 2024 3:10pm - 3:20pm HST
Nautilus 1

3:15pm HST

CE 6 - Modeling Evapotranspiration in Greenhouse and Indoor Cutting Propagation
Thursday September 26, 2024 3:15pm - 3:30pm HST
Current mist irrigation practices in plant propagation do not represent the variable rate of water loss experienced in a greenhouse environment and often rely on grower experience for adjusting irrigation settings. Automated control logic for these systems can be improved by considering climate data to predict the real-time water loss in the propagation environment. The objectives of this study were to 1) identify the impacts of environmental parameters on the water loss of young plants in greenhouses and indoor environments and 2) develop an evapotranspiration model based on the key parameters identified to achieve weather-based mist irrigation control for resource-efficient plant propagation in controlled environment agriculture. Data sets that include climate data, water applied, and water loss were collected in greenhouse sunlight and indoor sole-source LED environments with unrooted chrysanthemum cuttings. Trials were completed in June and September in 2023 and February in 2024 to collect diverse minute-by-minute data in each environment. Measurements using load cells indicated highly variable water loss in the greenhouse environment. Conversely, in the indoor environment with lower and constant photosynthetic photon flux density (PPFD) and reduced vapor pressure deficit via a fog system, rate of water loss was lower and consistent over time. The key parameters for modeling water loss, found using stepwise regression, were PPFD, leaf temperature, and air vapor pressure (temperature and relative humidity). These climate parameters were correlated with water loss data over time to yield a simple evapotranspiration equation that could be programmed into commercial environmental control systems to improve current irrigation scheduling programs. By improving the control of mist irrigation to take climate data into account, growers have the potential to reduce crop losses (“shrinkage”), reduce rooting time, and improve water use efficiency.
Speakers
DC

Daniel Crawford

University of Florida
Thursday September 26, 2024 3:15pm - 3:30pm HST
Coral 1

3:15pm HST

CITR 3 - Comparative Transcriptomic and Metabolomic Studies Provide Insights into Early Tolerance Response of Citrus to CLas Infection
Thursday September 26, 2024 3:15pm - 3:30pm HST
Citrus Huanglongbing (HLB, or citrus greening disease) has caused over 90% production losses since it was first reported in Florida in 2005. The unknown pathogenicity of the causative pathogen CLas hinders the development of sustainable disease management. Thus, understanding citrus host response to CLas, particularly at initial infection stage, is important for early disease detection and effective long-term HLB management. In this study, transcriptomic and metabolomic studies were conducted in a 2-day-post-inoculation (dpi) window, between HLB-tolerant LB8-9 Sugar Belle ® mandarin-like hybrid (SB; Citrus reticulata) and HLB- sensitive Valencia sweet orange (VAL; C. sinensis). CLas inoculation treatments included two controls no asian citrus psyllid (ACP) and CLas-negative ACP, plus CLas-positive ACP. Data were collevted at four time points: 2-, 12-, 24-, and 48-hour-post-inoculation (hpi). The results reveal that SB indicates immediate transcriptomic-level response from 2 hpi, compared with the delayed response in VAL from 24 hpi. The initial CLas-responsive differentially expressed genes (DEGs) in SB are related to plant defense response to Gram-negative bacterium, kinase activity and protein-kinase derived complex. DEGs that are categorized in plant defense response to Gram-negative bacterium are mostly associated with the pectinesterase inhibitors (PEIs) family which primarily alters the localized pH of the cell wall and strengthens cell wall integrity. On metabolomic level, SB shows rapid and high flavonoid content accumulation that reduces CLas-triggered stress and counteracts the initial infection. In VAL, the low flavonoid content accumulation removes reactive oxygen species (ROS) less efficiently which leads to more stress and cell death. Further investigation and validation on the proposed pathway are needed to confirm the early stage transcriptomic and metabolomic response of citrus tolerance response to CLas infection.
Speakers
ZW

Zimmy Wang

UF CREC
Co-authors
FG

Frederick Gmitter

University of Florida
NA
JL

Jingwen Li

University of Florida
NA
RT

Ronald Tapia

University of Florida/IFAS Citrus Research and Education Center
YW

Yu Wang

University of Florida
Thursday September 26, 2024 3:15pm - 3:30pm HST
South Pacific 2

3:15pm HST

HSMP 2 - Alzheimer’s Disease: Prospecting for Sterubin in California Yerba Santa
Thursday September 26, 2024 3:15pm - 3:30pm HST
California yerba santa (Eriodictyon californicum) is a chaparral shrub of western California and south western Oregon. Its leaves are rich sources of natural flavonoids. Leaves collected from wild stands in general contain the flavonoids homoeriodictyol, eriodictyol, hesperetin, and smaller amounts of other flavonoids. These flavonoids are of possible medical value and are subjects of intensive medical research. California yerba santa leaves containing substantial amounts of the flavonoid sterubin would be of special interest due to sterubin’s potential activity against the enzymatic and inflammatory pathways leading to Alzheimer’s disease in humans as discovered by the Salk Institute of La Jolla, California. We collected leaf samples from SW Oregon through California over the range of plant distribution. Not all areas were sampled. Total flavonoid content in excess of 10 percent of leaf dry weight were common. Leaves with sterubin content were relatively rare. Sterubin content of several samples exceeded 5 percent of leaf dry weight.
Speakers
CS

Clinton Shock

Scientific Ecological Services
Co-authors
MW

Mei Wang

USDA, ARS, NPURU
Thursday September 26, 2024 3:15pm - 3:30pm HST
Kahili

3:15pm HST

NUR 2 - Navigating the Interplay of Climate Stress and Pest Pressure in Shade Tree Nursery Production: Insights from Oregon and Tennessee
Thursday September 26, 2024 3:15pm - 3:30pm HST
The plant nursery production industry in Oregon and Tennessee faces escalating challenges from climate change, particularly concerning shade trees like red oak (Quercus rubra) and red maple (Acer rubrum). This research investigated the physiological responses of these species to fluctuations in soil moisture, vapor pressure deficit (VPD), and leaf temperature (Tleaf) through field experiments in Oregon's Willamette Valley and Tennessee's nursery regions. Monitoring stomatal conductance (gs) and stem water potential (Ψs) under varied conditions revealed distinct responses between the two species, with red maple exhibiting greater sensitivity to soil moisture and VPD compared to red oak. Additionally, a novel correlation between VPD and maple gas exchange underscores the significance of atmospheric moisture dynamics in plant water management strategies. Furthermore, assessing the impact of abiotic stressors on flatheaded borer (FB) attacks, we found that drought-stressed red maple trees experienced the highest borer infestations. Plant growth was adversely affected by all stressors, with drought stress exhibiting the most detrimental impact. Our findings underscore the complexity of plant responses to climate stress and highlight the necessity of informed water management practices for sustainable nursery production in diverse regional contexts. Bridging knowledge gaps in plant hydraulic physiology can empower growers to adapt to evolving environmental conditions and ensure the resilience of shade tree production systems. Further research is crucial to deepen our understanding of plant hydraulic physiology and its implications amidst climate change-induced challenges.
Speakers
avatar for Lloyd Nackley

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
Co-authors
AL

Anthony LeBude

north carolina state university
NA
AW

Anthony Witcher

Tennessee State University
NA
DM

Dalyn McCauley

Oregon State University
KA

Karla Addesso

Tennessee State University
NA
Thursday September 26, 2024 3:15pm - 3:30pm HST
South Pacific 4

3:15pm HST

PUBHORT/Hort Industry- Native Trees for Public Gardens: Building a University Teaching Collection for Increased Student Learning, Visitor Engagement, and Carbon Sequestration
Thursday September 26, 2024 3:15pm - 3:30pm HST
Changing climate patterns challenge the long-term health and survivability of common mid-Atlantic U.S. tree species, including climax species such as oaks, elms, and beeches. Evidence of tree loss in natural and managed ecosystems and residential areas demonstrates the need for public gardens to consider alternative species that will adapt to changing conditions, maximize carbon sequestration, and provide aesthetic value. University-affiliated Rutgers Gardens has long served to demonstrate landscape best practices and species selection for students, industry professionals, and homeowners; additionally, carbon sequestration has become a primary function. Continuing a tradition of education, Rutgers Gardens is creating a Native Trees teaching collection including over one hundred native species selected for their ecosystem functions, ecological niche, and landscape aesthetics, on an approximately four-acre site with the goal of maximizing carbon sequestration and educational value. Selected specimens include those native to New Jersey and the wider mid-Atlantic region and/or southeastern United States. This allows for a comprehensive collection that supports larger ecosystem functions, especially as tree species composition in the broader region is likely to shift with time. As major tree species are lost due to climate-influenced changes in pest, disease, and environmental pressures, preparing for continuous carbon sequestration by including species likely to thrive in our changing climate will maximize the environmental benefit. By including a mix of small, medium, and large (at maturity) trees, the design maximizes ecosystem niches occupied throughout the planting area and provides a comprehensive demonstration for students, homeowners, and industry professionals, modeling native trees for consideration in landscape plantings throughout the state. Specimens include straight species, as well as cultivars within the genera to demonstrate variability in true native trees and “nativars,” or cultivars of native trees. A density of approximately 25 trees per acre planted allows for the integration of new trees with existing specimens, including trees and shrubs that represent historical iterations of present-day Rutgers Gardens, and accommodates the design of accessible paths and gathering spaces between plantings to maximize educational opportunities. Public gardens present many opportunities for education and demonstration, especially within a university setting. Yet, challenges exist when considering complex land use history, student and faculty needs, visitor expectations, and the interests of diverse stakeholders such as members, volunteers, and staff of public gardens. Lessons learned include the importance of positive and clear communication among stakeholders to ensure project benefits are recognized and shared for educational and ecological success in public spaces.
Speakers
LE

Lauren Errickson

Director of Rutgers Gardens & Campus Stewardship, Rutgers, the State University of New Jersey
Co-authors
MM

Maxine Marvosa

Rutgers, the State University of New Jersey
NA
Thursday September 26, 2024 3:15pm - 3:30pm HST
Lehua Suite

3:15pm HST

VCM 5 - Predicting Potato Tuber Yield Through Hyperspectral Signals and Machine Learning
Thursday September 26, 2024 3:15pm - 3:30pm HST
Potato production is crucial for global food security, and with an increasing demand for food and a diminishing supply of fertile land, there is a need to boost production. Remote sensing technologies, such as high-resolution hyperspectral sensors, have the potential to provide valuable insights into potato growth, yield, and quality. Narrow spectral bands captured by these sensors are directly linked to biophysical parameters and can accurately estimate crop parameters. Recent studies have utilized hyper-spectral imagery acquired from proximal sensor such as ASD FieldSpec to estimate various crop parameters and yield. The results from these studies are promising, indicating that hyper-spectral sensors have the potential to improve crop management and agricultural practices. Moreover, the integration of remote sensing data with advanced analytical techniques, such as machine learning, helps in accurately estimating yield and yield components. In this study we are testing two machine learning such as PLSR and RF to predict biomass and N uptake in-season. Results from this indicate that PLSR performs better in predicting biomass and N uptake in potatoes. Moreover, yield can be best estimated at tuber bulking stage.
Speakers
RS

Ravinder Singh

Graduate Research Assistant, UF
Co-authors
LS

Lakesh Sharma

University of Florida
Dr. Lakesh Sharma is an assistant professor of soil fertility and sustainable agriculture at the University of Florida in Gainesville, FL. Lakesh has been farming since he was a child on his own farm. His academic school journey started in 2000. He is currently working on nutrient... Read More →
RS

Rajkaranbir Singh

University of Florida
NA
SK

Sehijpreet Kaur

Agronomy, UF
NA
SS

Simranpreet Sidhu

University of Florida
NA
Thursday September 26, 2024 3:15pm - 3:30pm HST
South Pacific 1

3:15pm HST

VGBR 2 - Genome-wide Association Study and Genome Prediction of Tallness Trait in Spinach
Thursday September 26, 2024 3:15pm - 3:30pm HST
Spinach (Spinacia oleracea L.) is a highly nutritious leafy green known for its abundance of health-promoting components. Plant height (tallness), particularly relevant for efficient machine harvesting, is a critical trait of interest in spinach cultivation. This study aimed to conduct a genome-wide association study (GWAS) to identify single nucleotide polymorphism (SNP) markers associated with tallness in spinach and to perform genomic prediction for this trait. GWAS was conducted on a panel of 307 USDA spinach germplasm accessions, utilizing 15,058 SNPs derived from whole-genome resequencing. Various statistical models, including GLM, MLM, FarmCPU, and BLINK, were employed in the analysis using the GAPIT 3 tool. Significant quantitative trait loci (QTL) were identified on chromosome 2, along with two QTL on chromosome 6. Specifically, the SNP marker SOVchr4_38323167 at 38,323,167 bp on chromosome 4, and two SNPs, SSOVchr6_8139833 and SOVchr6_91175684 at 8,139,833 bp and 91,175,684 bp respectively on chromosome 6, exhibited robust associations with tallness. Genomic prediction demonstrated high accuracy, with a prediction ability (GA) represented by an r value of 0.71 in the panel. The identified SNP markers and genomic prediction metrics provide valuable tools for breeders to select spinach plants and lines with desired tallness traits through marker-assisted selection (MAS) and genomic selection (GS), thereby enhancing spinach breeding efforts.
Speakers
IA

Ibtisam Alatawi

University of Arkansas
NA
Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
BM

Beiquan Mou

USDA-ARS
NA
GB

Gehendra Bhattarai

University of Arkansas
HX

Haizheng Xiong

University of Arkansas
HM

Hanan Mohammedsaeed Alkabkabi

University of Arkansas
NA
KC

Kenani Chiwina

University of Arkansas
NA
Thursday September 26, 2024 3:15pm - 3:30pm HST
South Pacific 3

3:20pm HST

PROP - Identifying Patterns of Clone Degeneration to Improve Diagnostics.
Thursday September 26, 2024 3:20pm - 3:30pm HST
Plant clones, because they are the product of asexual reproduction, are populations of genetically identical individuals and are important in agriculture, horticulture, and ecology. Although clones can be maintained for hundreds to thousands of years through repeated cycles of vegetative reproduction, degeneration of plant fitness and/or productivity often occurs with increasing age and/or cycles of propagation. While powerful diagnostics allow increasingly accurate identification of the underlying causes for biotic (diseases, pest, etc., and abiotic (nutrient deficiency, inadequate chill, etc.) breakdowns in normal growth and development, genetic/epigenetic failures remain poorly understood, often being generalized as ‘off-types’. A major impediment to the effective deployment of emerging tools for identifying causes of genetic/epigenetic failures is the uncertainty as to where the failure first occurred, which is necessary to identify the most appropriate tissues for testing. Characteristic patterns of clone degeneration can be used to distinguish among different types of failure as well as recommend appropriate methods and tissues for analysis. Clone degeneration from ‘General-aging’ is due to the accumulation of many small-affect deleterious factors making targeted genetic/epigenetic diagnosis difficult though tracking changes in selected methylation profiles could serve as indicators of ‘clone-age’ particularly when ‘slow-to-age’ epicormic meristems are available for reference. ‘Bud-sports’ results from genetic/epigenetic changes in mitotically active cells resulting in distinct sectoral chimeras in subsequent shoot growth and development that can be targeted for molecular and phenotypic analysis. In contrast, ‘epigenetic-imprinting’ seems to be induced at the tissue rather than single cell level making the determination of initial induction time and site difficult to determine. In addition, because most shoot structure in temperate perennials is largely preformed during the previous growing seasons, the time and location between the initial imprinting and its first phenotypic detection can be months to years. Examples, largely from tree crop production, will be presented showing that expression patterns within these major groups can further delineate the specific nature of clone degeneration including the identification of appropriate tissues for testing.
Speakers
TG

Thomas Gradziel

University of California
Thursday September 26, 2024 3:20pm - 3:30pm HST
Nautilus 1

3:30pm HST

PROP - Evaluating Leaf Cutting Success for Achimenes Propagation
Thursday September 26, 2024 3:30pm - 3:40pm HST
The hot water plant (Achimenes hybrids) is a colorful gesneriad plant and can be
used as potted decorative plants indoors. These impatiens-like plants can also
be used outdoors in mixed containers and in hanging baskets. Increased
commercial production of Achimenes is limited for a couple of reasons.
Achimenes are typically propagated by rhizomes and rhizome production is
limited due to poorly understood plant responses to environmental conditions to
develop rhizomes and subsequent dormancy release. Moreover, rhizomes also
randomly develop on stolons and enlarged roots in growing media, making
harvesting challenging. One alternative method to asexually propagate
Achimenes would be from stem tip cuttings or leaf cuttings. This study
investigated three different Achimenes selections and the effects of bottom heat
and three different rooting hormone concentrations [0; 1,000; and 8,000 ppm
indole-3-butryic acid (IBA)] on root and shoot development on Achimenes leaf
petiole cuttings. Generally, leaf cuttings for all three selections developed more
shoots without bottom heat, although not always significant. All leaf cuttings, for
all selections propagated with and without bottom heat, developed roots and
shoots. The percent leaves developing adventitious shoots were lowest for
leaves treated with bottom heat for 0 and 8,000 ppm IBA in ‘A16’ at 80% and for
8,000 ppm IBA in ‘A23’ at 60%. Root ratings, based on a scale of 0 (no
adventitious roots) to 5 (significant number and length), were significantly higher
across all auxin levels for leaves grown without bottom heat in ‘A16’ and ‘A23’.
This study demonstrated that leaf petiole cuttings for Achimenes can be
successful and result in rooted cuttings producing adventitious shoots, which
could be potentially further propagated.
Speakers
CT

Chad T. Miller

Assistant Professor; Department of Horticulture and Landscape, Colorado State University
Thursday September 26, 2024 3:30pm - 3:40pm HST
Nautilus 1

3:30pm HST

CITR 3 - Exploring Leaf Nutrients and Fruit Quality Attributes Relationship in Fresh Market Citrus Using Artificial Neural Networks and Linear Regression Models
Thursday September 26, 2024 3:30pm - 3:45pm HST
The market value of fresh citrus fruit is greatly influenced by the internal and external fruit qualities, such as peel color, total soluble solids (TSS), titratable acid (TA), and fruit size. Abundance or deficiency of mineral nutrients in citrus trees are among the most important key factors that affect fruit qualities. Various regression models using leaf nutrient parameters and quality indices have been suggested, but their accuracy and generalization performance in estimating fruit quality remain insufficient. In this research, we used both artificial neural network models (ANN) and a multiple linear regression model to explore the effects of leaf nutrient concentration on citrus fruit quality. For ANN models, we applied two transfer functions and five different training functions to establish the model with best prediction accuracy using TensorFlow framework through Python software. The models were evaluated using statistical performance evaluation criteria including the coefficient of determination (R2), root mean square error (RMSE), mean absolute error (MAE), and mean absolute relative error (MARE). Sensitivity analysis of the prediction models was conducted to discern the significant contribution of leaf mineral nutrients to the respective fruit quality parameters. The response surface analysis determined the optimal range of these mineral elements, which is critical for guiding precision fertilization in fresh market citrus fruit for improving fruit quality. Comprehensive results will be presented during the conference. Keywords: artificial neural network, fruit quality, citrus, mineral nutrients, sensitivity analysis
Speakers
avatar for Shankar Shrestha

Shankar Shrestha

PhD graduate student, University of Florida
Co-authors
AS

Arnold Scumann

University of Florida
NA
Thursday September 26, 2024 3:30pm - 3:45pm HST
South Pacific 2

3:30pm HST

HSMP 2 - Genomic Variation in Wild Sabadilla (Schoenocaulon officinale, Melanthiaceae) Populations for Key Phenotypic Traits of Interest for Domestication and Breeding
Thursday September 26, 2024 3:30pm - 3:45pm HST
Sabadilla (Schoenocaulon officinale), a perennial geophytic species with various medicinal properties and historical uses as a natural insecticide or “green pesticide”, has been used by human cultures in the Americas for >2,000 years. Its history parallels the domestication of pyrethrum (Chrysanthemum cinerariifolium) in Europe with similar green pesticidal properties, although the active ingredients differ. Alkaloids extracted from sabadilla seeds have been used to control many insect pests also killed by pyrethrum as well as additional insect pests. With the renewed consumer interest in botanically derived products and the growth of organic chemical industries, S. officinale has re-emerged as a viable source for insect management. To meet market demands, rapid crop domestication must occur. However, sabadilla is an herbaceous perennial geophyte (tunicate bulbs) with an extended juvenility period of at least 64 wks and little is known about the phenotypic and genetic structure of wild populations, alkaloid content variation, and flowering times from seed. Current production is limited to wild-harvested seed (open-pollinated) in Venezuela which is threatening native populations. The purpose of this study was to assess phenotypic and genotypic structure of wild sabadilla populations and seed lots; species comparison with S. texanum were also performed. Through introduction of wild-sourced composite seed into a modern breeding and cropping system, phenotypic traits (rate of seed germination, growth rates, factors of flowering, timing of seed maturity, seed yield, and alkaloid content) were assessed in multiple locations. Genotypic analyses (GBS; DArTseqLD) were used to identify low density SNPs and determine genetic structure within and among wild species populations. Seed lots from varying locations in Venezuela showed distinct SNP arrays with little overlap. SNP-trait association of seed germination weeks was an unexpected, rather tight linkage. Both species are genetically distinct from each other. Phenotypic and genotypic data will be integrated with a genome-wide association study (GWAS) to identify SNP-trait associations and aid in marker-assisted selection.
Speakers
AR

Albert Radloff

University of Minnesota
Co-authors
NA

Neil Anderson

University of Minnesota
NA
Thursday September 26, 2024 3:30pm - 3:45pm HST
Kahili

3:30pm HST

NUR 2 - The Effects of Supplemental Nickel on Mouse Ear Disorder of Three Diospyros Species
Thursday September 26, 2024 3:30pm - 3:45pm HST
American persimmon (Diospyros virginiana L.) is a multipurpose tree endemic to the eastern United States with potential for broader use in managed landscapes or for producing desirable fruits. Whereas most members of this genus originate from tropical and subtropical regions, the American persimmon could expand landscape diversity and fruit production applications in northern climates. Due to purported challenges with transplant success, American persimmon is likely best suited to cultivation in containers. Recent observations of container-nursery crop production indicates American persimmon is susceptible to mouse ear disorder (MED), a function of nickel deficiency. We hypothesized that American and Asian-origin persimmon species are susceptible to MED and that supplementing nickel with a foliar spray will ameliorate the disorder. Our objectives were to characterize symptoms of non-treated MED with American (D. virginiana), Japanese (D. kaki), and dateplum (D. lotus) persimmon as well as to determine if MED could be corrected by foliar application of nickel or other compounds presumed to interact with the urease metabolic pathway, such as urea. In a randomized greenhouse study, seedlings of American, Japanese, and dateplum persimmons were evaluated by comparing a non-treated control (H2O spray), to foliar spray treatments of NickelPlus® (169 ppm), NiCl2 (169 ppm), urea (0.325 g/L), and combined NiCl2 (169 ppm) and urea (0.325g/L). Following treatment, plants were evaluated using a MED severity rating scale, leaf characterization metrics (greenness, count, surface area, dry mass, and specific area), as well as metrics characterizing stem traits (elongation and dry mass). Compared to the non-treated control, leaf surface area increased by ~56%, ~61%, ~25%, and ~52% for the Nickel Plus®, NiCl2, Urea, and combined NiCl2 Urea treatments, respectively, when pooled across species and cultivar. These results suggest nickel supplements are effective at increasing important growth metrics like leaf surface area for Diospyros species displaying MED symptoms. This study offers valuable insights for improving the cultivation of persimmons in container nursery production settings, contributing to the development and advancement of American persimmon as an emerging specialty crop.
Speakers
AH

Alyssa Headley

University of Minnesota-Twin Cities
Co-authors
BM

Brandon Miller

University of Minnesota-Twin Cities
Thursday September 26, 2024 3:30pm - 3:45pm HST
South Pacific 4

3:30pm HST

PUBHORT/Hort Industry - Future Directions of Horticultural Research Among Botanical Gardens and Arboreta in the United States
Thursday September 26, 2024 3:30pm - 3:45pm HST
Botanical gardens and arboreta maintain globally important collections for conservation and education with efforts to constantly strive for excellence in propagation, cultivation, and collection preservation. Methods of cultivating plants, learning from successes and challenges, with the ability to disseminate that knowledge is paramount for improving techniques and outcomes. However, the underlying field of horticultural research is not well defined, and results of plant cultivation techniques are often only shared informally rather than published. We explored how horticultural research practitioners perceive the field of horticulture research and excellence, how they are involved, and the most urgent needs of future horticultural research among gardens and arboreta. We conducted an internet-based survey of the status of horticultural research amongst the United States members of the American Society for Horticultural Research (ASHS), American Public Garden Association (APGA), Botanical Garden Conservation International (BGCI), and the Interactive Community of Arboreta (ArbNet), Level II, III, and IV members. 128 respondents from 116 institutions across 34 of the United States completed the survey. As conservation needs, changing agricultural paradigms, and climate change impacts continue to increase, we find future research needs are increasingly holistic and focus on species and variety conservation, ecology, and mitigating pests and diseases. The respondents were variously involved in horticulture research and the main challenges were funding, time, and personnel resources. Horticultural knowledge is largely practical and shared informally and there is a need for recognition and means of sharing practical research as well as technical research. This study presents a new framework for horticultural research supporting the horticulture community with the conceptualization, communication, and implementation of horticultural research.
Speakers
avatar for Michael Opgenorth

Michael Opgenorth

National Tropical Botanical Garden
Co-authors
DR

David Rae

Stanley Smith (UK) Horticultural Trust
NA
JA

Julia Avila

National Tropical Botanical Garden
NA
NR

Nina Ronsted

National Tropical Botanical Garden
NA
SB

Sarah Bryce

National Tropical Botanical Garden
NA
Thursday September 26, 2024 3:30pm - 3:45pm HST
Lehua Suite

3:30pm HST

VCM 5 - Evaluating King Stropharia Mushroom as an Intercrop in Asparagus and Tomato Production
Thursday September 26, 2024 3:30pm - 3:45pm HST
Stropharia rugosoannulata (L.), the King Stropharia or Wine Cap mushroom, is a wood-loving fungus that grows well on organic mulches. Some vegetables can be successfully grown using organic mulches like woodchips or straw. As a result, farmers may be able to enhance their income by intercropping Stropharia mushrooms with their vegetable crops. However, no study has been identified that assesses this strategy's potential or effect on vegetable yields. Thus, a Stropharia-asparagus intercrop was evaluated by applying woodchips at three depths (4, 8, and 12 in), and a Stropharia-tomato intercrop was evaluated using woodchips, wheat straw, and soy straw (all at 6 in depth). Both experiments utilized a randomized complete block design (RCBD) with four replications and included bareground controls. The tomato study also included a positive mulch control using black plastic. In the fall of 2021, black plastic, inoculated wheat straw, and uninoculated soy straw and woodchip mulch provided earlier harvest than unmulched plots, while the soy treatments and bareground and black plastic controls increased total fruit numbers. In 2022, overall tomato production decreased, resulting in no marketable fruit. Across both 2022 and 2023 asparagus harvest began earlier with decreasing depths of mulch, and therefore lasted longer. Inoculated plots also produced more marketable spears than uninoculated plots. And, 12 in woodchip mulch significantly inhibited asparagus emergence and is therefore not recommended. These results suggest that a Stropharia-tomato intercrop may not be feasible without additional work, though a Stropharia-asparagus intercrop shows great promise. In fact, in 2023, mushrooms were observed in uninoculated plots demonstrating the gregarious growth of Stropharia in woodchip mulch on asparagus plots. The relative success in asparagus plots supports a need for further research to evaluate other Stropharia-vegetable [or fruit] intercrop candidates and/or strategies to improve compatibility.
Speakers
OS

Olalekan Sipasi

Kansas State University
Sipasi Olalekan Ayodele is a Ph.D. Candidate at the Department of Horticulture and Natural Recourses at Kansas State University, ONE Champion 2017, Fellow Thinking School Africa, 2016 Winner of the African Youth Award in Agriculture, a seasoned NYSC SDGs Facilitator, The Future Award... Read More →
Co-authors
CL

Calvin Liu

Kansas State University
NA
JC

Jeremy Cowan

Kansas State University
NA
Thursday September 26, 2024 3:30pm - 3:45pm HST
South Pacific 1

3:30pm HST

VGBR 2 - Capitalizing on the Global Capsicum Core Collection to Advance Pepper Breeding
Thursday September 26, 2024 3:30pm - 3:45pm HST
Unlike other crops, access to genetic and genomic tools enabling more efficient breeding is limited in pepper. The majority of the research in pepper is based on analyzing traits in biparental populations, and in addition, limited access to pathogen strains or races reduces the wide-scale applicability of the developed molecular markers across populations and breeding programs. In contrast to research in bi-parental populations, genome-wide association studies utilizes the broad range of genetic diversity present in natural populations, including historical recombination events, which allows for the identification of more alleles potentially associated with the trait. A well-designed core collection captures the diversity that is present in an entire germplasm collection, which is crucial for preserving unique alleles and traits and facilitates more efficient phenotyping and GWAS. A core collection of 423 accessions was assembled representing the genetic diversity present in the G2P-SOL global collection of 10,038 wild and cultivated Capsicum accessions from 10 major genebanks .The G2P-SOL Capsicum core collection has been phenotyped for resistance to anthracnose, bacterial wilt, phytophthora blight, and Chili leaf curl virus, as well as for heat stress component traits in several locations in Asia. Genome wide association studies have revealed multiple significant loci associated with the individual traits. These loci are being utilized in the breeding program to more efficiently develop and release cultivars.
Speakers
avatar for Derek Barchenger

Derek Barchenger

World Vegetable Center
Co-authors
HZ

Herbaud ZOHOUNGBOGBO

World Vegetable Center
NA
MK

Manoj Kumar Nalla

World Vegetable Center
NA
RS

Roland Schafleitner

World Vegetable Center
NA
SL

Shihwen Lin

World Vegetable Center
NA
TL

Tsunghan Lin

World Vegetable Center
NA
YW

Yanwei Wang

World Vegetable Center
NA
YL

YaPing Lin

World Vegetable Center
NA
Thursday September 26, 2024 3:30pm - 3:45pm HST
South Pacific 3

3:45pm HST

VGBR 2 - Private-public Partnership for Sustainable Cucurbit Breeding and Production in Asia
Thursday September 26, 2024 3:45pm - 4:00pm HST
The global cucurbit breeding program of the World Vegetable Center (WorldVeg) focuses on tropical pumpkin (Cucurbita moschata) and four gourds: bitter gourd (Momordica charantia), ridge gourd (Luffa acutangula), sponge gourd (Luffa aegyptica = cylindrica) and bottle gourd (Lagenaria siceraria). This breeding program uses the diversity of hitherto unexploited landrace collections to develop high yielding and disease resistant lines and F1 hybrids with a range of fruit types suitable for various market segments. The program supports breeding research of partners from national agricultural research and extension systems organizations and the private seed industry to develop better cucurbit cultivars for the benefit of stakeholders along the vegetable value chain. To facilitate these partnerships, the WorldVeg cucurbit team displays improved cucurbit lines and F1 hybrids during the cucurbits open field days at the WorldVeg East and Southeast Asia Research and Training Station, located on the campus of the Kasetsart University in Kamphaeng Saen, Thailand. This annual event attracts breeders, pathologists, product development managers, marketing and sales managers, R
Speakers
ND

Narinder Dhillon

World Vegetable Center
Narinder Dhillon (India) is a Principal Plant Breeder-Cucurbit
Thursday September 26, 2024 3:45pm - 4:00pm HST
South Pacific 3

3:59pm HST

Plant Growth Regulation 2 (PGR 2)
Thursday September 26, 2024 3:59pm - 6:00pm HST
Quantifying Growth Control of Ornamental Millet ‘Jester’ with Ancymidol, Ethephon, Flurprimidol, Paclobutrazol, and Uniconazole Substrate Drenches - Lauren Seltsam
Controlling growth of Brunnera macrophylla L. ‘Jack Frost’ with Uniconazole Substrate Drenches or Sprays - William Rich
Uniconazole Substrate Drenches Control Growth of Buddleia Cultivars - Lark Wuetcher
Effects of Weather Conditions on the Efficacy of ACC as a Peach Thinner - Jozsef Racsko
Mode of Action and Uptake Investigations of ACC as a Peach Thinner - Jozsef Racsko
Physiological Mechanism of Silicon’s Enhancement of Drought and Heat Tolerance in Creeping Bentgrass - Xunzhong Zhang
Effect of Light Quality and Intensity on Cannabis Photosynthetic Activity - Philip Wiredu Addo
Enhancing the quality of novel greenhouse crops through dynamic LED lighting - Rose Seguin

Moderator
LS

Lauren Seltsam

The Ohio Sate University,
Thursday September 26, 2024 3:59pm - 6:00pm HST
South Pacific 4

4:00pm HST

PGR 2 - Quantifying Growth Control of Ornamental Millet ‘Jester’ with Ancymidol, Ethephon, Flurprimidol, Paclobutrazol, and Unic
Thursday September 26, 2024 4:00pm - 4:15pm HST
Plant growth regulators (PGRs) are a valuable tool in the ornamental industry. Whether it is for promoting or controlling growth, PGRs give growers the opportunity to produce high quality crops in the face of their production or shipping challenges. Often, substrate drench applications provide greater growth control, require less labor, and have shortened re-entry intervals than spray applications. Current PGR recommendations for ornamental millet (Pennisetum glaucum ‘Jester’) are for spray applications; therefore, the objectives of this study were to evaluate the efficacy of different PGRs applied as substrate drenches to improve marketability and control growth of ornamental millet ‘Jester.’ Seeds were received from a commercial supplier and sown into 288-cell plug trays (5-mL individual cell vol.) filled with a pre-moistened commercial soilless propagation substrate. After 24 d, young plants of similar heights, basal diameters and culm were transplanted with one plant per 11.4-cm-diameter container filled with a commercially available peat-based substrate. At 7 d after transplant, plants received 59-mL aliquots of solution containing 0 (deionized water control),1, 2, 4, 8, or 16 mg·L–1 ancymidol, flurprimidol, paclobutrazol, or uniconazole or 25, 50, 75, 100, or 200 mg·L–1 ethephon. Plants were grown at bench-level in a glass-glazed greenhouse with an air temperature set point of 23 °C, and supplemental day-extension lighting provided by light-emitting diode lamps from 0600 to 2200 hr (16-h photoperiod) to achieve a daily light integral of ~14 mol·m–2·d–1. Data were collected four weeks after drench. For each chemical, effects of PGR concentration were analyzed independently, and means were separated using Tukey’s honestly significant differences. For all analyses, a P ≤ 0.05 was used to determine significant effects. In general, ancymidol and ethephon provided the best growth control, while flurprimidol and uniconazole were found to be inadequate for drenches at the concentrations investigated due to unmarketable plants. Paclobutrazol resulted in unmarketable plants at concentrations ≥ 1 mg·L–1. Ancymidol substrate drenches containing 1 to 16 mg·L–1 resulted in plants that were 3% to 21% shorter and 3% to 14% smaller plants, respectively, than untreated plants. Similarly, increasing ethephon substrate drench concentrations from 1 to 16 mg·L–1 resulted in plants that were 7% to 36% shorter and 27% to 41% smaller plants compared to the untreated control. Results from this study establish substrate drench recommendations for ornamental millet ‘Jester’; however, further investigations are needed to assess growth control responses of other ornamental millet cultivars.
Speakers
LS

Lauren Seltsam

The Ohio Sate University,
Co-authors
GO

Garrett Owen

The Ohio State University
Thursday September 26, 2024 4:00pm - 4:15pm HST
South Pacific 4

4:00pm HST

American Pomological Society Business Meeting
Thursday September 26, 2024 4:00pm - 5:30pm HST
Moderator
avatar for Ksenija Gasic

Ksenija Gasic

Clemson University
Thursday September 26, 2024 4:00pm - 5:30pm HST
South Pacific 1

4:00pm HST

Interest Group Session: Climate Ready Landscape Plants
Thursday September 26, 2024 4:00pm - 6:00pm HST
The overall goal of this session is to highlight the latest advancements from the USDA Agricultural Marketing Service Specialty Crop Multi-State Program funded project titled “Climate Ready Landscape Plants”.

Coordinator(s)
  • Youping Sun, Utah State University, Department of Plants, Soils & Climate, Logan, Utah, United States
Speaker/Participant(s)
  • Jared Sisneroz, UC Davis
    Climate Ready Landscape Plants Trialed in Davis, CA
    Summary: To develop landscape irrigation recommendations, 22 taxa of landscape plants were evaluated under three levels of deficit irrigation in a field trial. The taxa consisted of common horticultural perennials and shrubs including multiple cultivars of Hibiscus syriacus, Nandina domestica, Rosa spp., and Salvia spp.
  • Soo-Hyung Kim, University of Washington, United States
    Variation in Landscape Plant Aesthetics, Growth, and Physiology to Deficit Irrigation Across the Western U.S. (20 mins)
    Summary: Climate change is causing more frequent and severe droughts in the Western U.S., while concurrently, about 70% of urban water use is delegated to landscape irrigation. Therefore, water conservation techniques in the horticultural space, such as planting water use efficient landscape plants, will be essential to reduce irrigation consumption. Five different taxa, Hibiscus syriacus ‘Gandini Santiago’ Purple Pillar®, Hibiscus syriacus 'ORSTHIB5x1' PPAF, Rosa ‘Meibenbino’ Petite Knock Out®, Rosa ‘ChewPatout’ Oso Easy® Urban Legend®, and Vitex ‘SMVACBD’ Blue Diddley®, were subjected to one of three water deficit treatments in six sites: Tucson, Arizona; Davis, California; Irvine, California; Aurora, Oregon; Logan, Utah; and Seattle, Washington. Plants were rated on foliage quality, flowering, pest tolerance, disease resistance, vigor, and overall appearance. Our results highlight the importance of climate-specific plant selection for reducing landscape water use while achieving satisfactory aesthetic qualities and growth of landscape plants.
  • Ursula Schuch, University of Arizona
    Climate Ready Landscape Plants Trialed in Tucson, AR
    Summary: Fifteen taxa of shrubs growing in a field in Tucson, Arizona were irrigated with three levels of irrigation based on local reference evapotranspiration (ETo) to assess growth and plant quality. Plants established during 2021 under 80% of ETo and in 2022 were irrigated at 20%, 50% or 80% of ETo. Irrigation was applied 2, 9, and 15 times between April 1 and October 31, 2022, for the low, medium, and high irrigation, respectively. Best performing plants were Asclepias linaria ‘Monarch Magnet’, Dodonaea viscosa ‘Emerald Ice’, Eremophila glabra ssp. carnosa ‘Winter Blaze’, Ericameria laricifolia ‘Aguirre’, Hamelia patens ‘Sierra Red’, Leucophyllum frutescens ‘San Antonio Rose’, Leucophyllum langmaniae ‘Rio Bravo’, Tecoma ‘Red Hot’ and Rosmarinus officinalis 'Arp'. Irrigation did not affect plant growth of these nine taxa from April to October. All nine taxa tested are low water use shrubs that can grow in the landscape with 20% of ETo in the low desert in Arizona. However, some may benefit from additional irrigation during the hottest time of the year for optimum performance.
  • Natalie Levy, South Coast Research & Extension Center, The University of California Agriculture and Natural Resources
    Climate Ready Landscape Plants Trialed in Irvine, CA
    Summary: During the historic California drought from 2011 to 2015, annual landscape water use averaged 38% of all urban water use. As climate extremes, population growth, and agricultural/industrial water demands continue to increase, urban landscapes are an essential area where water conservation efforts must be improved. Deficit irrigation trials of ornamental plants began at the University of California, Davis (UCD) in 2004 and evolved into the University of California Landscape Plant Irrigation Trials (UCLPIT™). In 2016, the UCD field site was replicated at UC Agriculture and Natural Resources’ South Coast Research and Extension Center (SCREC) in Irvine, California. The new field site allowed for direct comparison of plant performance and irrigation requirements of the same plant material across two soil types and climate zones.
  • Youping Sun, Utah State University
    Field Trials of Landscape Plants under Reduced Irrigation Frequency
    Summary: Utah has experienced significant drought conditions, with 99.3% of the land under drought stress in 2023. In response to this challenge, water-efficient landscaping with low-water-use landscape plants is gaining popularity in arid and semi-arid regions. This study was to investigate the overall appearance, plant growth, and physiological response of ten ornamental plants to deficit irrigation. The selected species included Caryopteris ×clandonensis ‘Blauer Splatz’ (Sapphire SurfTM bluebeard), Cercis canadensis (eastern redbud), Cercis occidentalis (western redbud), Cotoneaster ×suesicusn ‘OSUCOT2’ (Emerald BeautyTM cotoneaster), Hesperaloe parviflora ‘Straight Up Red’ (‘Straight Up Red’ Texas red yucca), Miscanthus sinensis ‘NCMS2B’ (bandwidth maiden grass), Physocarpus opulifolius ‘Diabolo’ (‘Diabolo’ ninebark), Physocarpus opulifolius ‘Little Devil’ (Little DevilTM ninebark), Rosa ×hybrida ‘Meifranjin’ (Blushing Drift® rose), and Vitex agnus-castus ×rotundifolia ‘Helen Froehlich’ (Summertime BluesTM vitex).
Moderator
YS

Youping Sun

Dr. Sun is an Associate Professor of Landscape Horticulture whose research focuses on understanding the whole-plant response to water stress, with an emphasis on water conservation, and developing protocols to produce native plants. He is the principal investigator for the ‘Climate... Read More →
Speakers
SK

Soo-Hyung Kim

Dr. Kim is a Professor and Plant Ecophysiologist whose research focuses on how plants interact with their environment at the whole-plant scale. He is the principal investigator for the ‘Climate Ready Landscape Plants’ project at the University of Washington.
NL

Natalie Levy

Dr. Levy is an Associate Specialist for Water Resources at the South Coast Research and Extension Center. She specializes in landscape plant water-use efficiency research, water resource management, and water pollution prevention/mitigation.
US

Ursula Schuch

University of Arizona
Dr. Schuch is a Professor and Extension Specialist in Environmental Horticulture in the School of Plant Sciences. Dr. Schuch’s research focuses on plant selection and management strategies to conserve water, maintain plant health, and aesthetic function. She is the principal investigator... Read More →
JS

Jared Sisneroz

UC Davis
Mr. Sisneroz is the project manager of the UC Landscape Plant Irrigation Trials (UCLPIT) and the ‘Climate Ready Landscape Plants’ programs. He specializes in landscape plant water-use efficiency research and water resource management.
avatar for Lloyd Nackley

Lloyd Nackley

oregon state university
Lloyd Nackley is a plant ecologist who applies a systems approach to improve nursery and greenhouse management. Nackley's research program at Oregon State University focuses on addressing four challenges facing nursery and greenhouse production in Oregon: irrigation application, pest... Read More →
Thursday September 26, 2024 4:00pm - 6:00pm HST
Lehua Suite

4:00pm HST

Interest Group Session: Crop Germplasm Committees (CGC) – Get Involved in Setting Germplasm Priorities
Thursday September 26, 2024 4:00pm - 6:00pm HST
The USDA National Plant Germplasm System (NGPS) is an invaluable resource to researchers and breeders of horticultural crops. Crop Germplasm Committees, with members from academic, private and governmental organizations provide expertise in a variety of topics, including collection priorities and vulnerabilities, identifying important traits for evaluation, and reviewing Plant Exploration and Evaluation grant proposals. The CGCs are a great opportunity for ASHS members to get more involved in setting germplasm related priorities for their crops of interest. This session gives an overview of the activities of the CGC and highlight activities of 3 specific CGCs. The talks will be followed by a 30-minute discussion session on avenues for increased interaction between the ASHS PICs and the CGCs to ensure that germplasm collection priorities are relevant to the needs of stakeholders.


Coordinator(s)

  • Cecilia McGregor, University of Georgia, Athens, GA, United States
Speaker/Participant(s)
  • Gayle Volk, USDA, Fort Collins, Colorado, United States
    Introduction to Crop Germplasm Committees: An Opportunity to have an Impact on Crop Collections in the USDA-ARS National Plant Germplasm System (20 mins)
    Summary: The USDA-ARS National Plant Germplasm System (NPGS) maintains over 620, 000 accessions of more than 200 crops at 22 sites around the United States. Most crop collections have Crop Germplasm Committees (CGC) that provide guidance to the curator with regard to vulnerabilities, acquisitions, maintenance, genotypic characterization, phenotypic evaluations and distribution. CGCs welcome new members to improve the quality and impact of the NPGS collections.
  • Glenn Wright, University of Arizona - Yuma Agriculture Center, Yuma, AZ, United States
    The Rewards and Challenges of Chairing Two Crop Germplasm Committees (20 mins)
    Summary: The Citrus CGC and the Date Palm CGC are both affiliated with the National Clonal Germplasm Repository for Citrus and Dates in Riverside, CA. Membership of both committees include representatives of the federal government, academia, and industry. Activities of both committees include advising the NCGRCD on critical issues, including staffing, infrastructure, threats to the genebank, and germplasm backup, acquisition, sanitation, and distribution. We also advise repository staff on project plans, relevant research, and strategic planning. Finally, the committees comment and approve germplasm evaluation, plant exploration and plant exchange proposals.
  • Kim Shearer, The Morton Arboretum, Lisle, IL, United States
    Seeing the Forest for the Trees (20 mins)
    Summary: The Woody Landscape Plant Crop Germplasm Committee has a somewhat unique task in that the wild crop relatives can include all of the trees and shrubs of all of the forests. As a group, we found that the task of identifying priorities and vulnerabilities limited to specific taxonomic categories seemed insurmountable. How could we predict an event like the introduction of emerald ash borer (Agrilus planipennis) wiping out native floodplain forests and masses of street trees? What can be lost in an uncertain future with the onset of climate change? And how could we communicate this vulnerability in a way that was politically palatable? In this talk, the strategy for developing a new crop vulnerability statement and QUAD will be presented along with some examples of projects that have been funded and implemented for both plant exploration and evaluation.
  • Cecilia McGregor, University of Georgia, Athens, GA, United States
    Crop Germplasm Committees: An Opportunity for Value-added Research (20 mins)
    Summary: The Cucurbit Crop Germplasm Committee (Cucurbit CGC) includes experts from local and global academic institutions and private industries, as well as the federal government. In addition to the routine activities of the CGC, the participation of several Cucurbit CGC members in the federally supported SCRI CucCAP and CucCAP2 projects provided the opportunity for improved coordination and alignment of federally funded academic research and germplasm priorities This contributed to the development of tools and resources that adds value to the existing Cucurbit germplasm collections.
Moderator
CM

Cecilia McGregor

University of Georgia
NA
Speakers
Thursday September 26, 2024 4:00pm - 6:00pm HST
Kahili

4:00pm HST

Interest Group Session: Impacts of Horticultural Practices to Improve Soil Health
Thursday September 26, 2024 4:00pm - 6:00pm HST
With soil health and regenerative agriculture continuing to gain interest, the Hort Industry Professional Interest group invites you to join our session exploring the research behind soil health and how soil health is impacting horticulture today. This session will have speakers from across various horticultural disciplines discussing their research and the implications for soil quality, horticultural productivity, regenerative agriculture and environmental sustainability.

Coordinator(s)
  • Holly Little, Acadian Plant Health, Technology, Walnut Grove, Ca, United States
Moderator(s)
  • Derek Woolard, Valent Biosciences, United States
Speaker/Participant(s)
  • Justin Moss, Oklahoma State, United States
    Urban Soil Health and Small Farm Soil Health (15 mins)
    Summary:
  • Tai Maaz, University of Hawai'i, United States
    Soil Health (15 mins)
    Summary:
  • Noa Lincoln, UH Mānoa, Hilo, Hawaii, United States
    Long Term Effects of Mono-Crop Conversion to Diversified Agroforestry (15 mins)
    Summary:
  • Nhu Nguyen, University of Hawai'i, United States
    Soil Microbial Ecology (15 mins)
    Summary:
  • Amjad Ahmad, University of Hawai'i, United States
    Organic Farming and Soil Health (15 mins)
    Summary:





Moderator Speakers
NL

Noa Lincoln

Associate Professor - Indigenous Crops, University of Hawaii at Manoa
Noa Kekuewa Lincoln is an Associate Professor with a focus on Indigenous Crops and Cropping Systems, in the College of Tropical Agriculture and Human Resources at the University of Hawai'i at Mānoa, and the PI of the Indigenous Cropping Systems Laboratory.  He is the President and... Read More →
Thursday September 26, 2024 4:00pm - 6:00pm HST
South Pacific 2

4:00pm HST

Interest Group Session: Sensing the Plant, for the Farmer's Benefit! A Historical Perspective Reflecting on the Work of Marc van Iersel
Thursday September 26, 2024 4:00pm - 6:00pm HST
 The recent loss of our colleague Marc van Iersel reminds us of the reasons our work in horticulture is so important. Marc's career was devoted to developing processes that judiciously utilized sensors to create efficient strategies to optimize crop quality and production for the grower. By examining the path of van Iersel’s work, we can understand how directed, mindful research can move quickly from the hands of the researcher to the farmer. Marc’s early work centered around developing smart irrigation systems utilizing biofeedback to measure soil moisture, with the goal of reducing water usage. More recently, Marc’s work integrated LED lighting with sensors including light sensors, moisture sensors, and low cost canopy and fluorescence detection to generate strategies for precise, energy efficient control of lighting in greenhouse and vertical growing platforms. Marc frequently consulted with growers to understand their needs and challenges, allowing the grower’s needs to frame his research. Marc also mentored the development of students, fellows, and colleagues in their own research, helping them discover how their programs could unfold in directions which would be most valuable. In this session we will examine the history of Marc’s research and continued work by colleagues, to ensure his lessons in how to provide practical answers for commercial horticulture are not lost. This two-hour session will include presentations from Marc's students and colleagues, and conclude with a 30-minute moderated Q&A/discussion.

Coordinator(s)
  • Jennifer Boldt, United States Department of Agriculture, Agricultural Research Service, Toledo, OH, United States
  • Neil Mattson, Cornell University, Ithaca, New York, United States
  • Melanie Yelton, Grow Big, United States

  • Bruce Bugbee, Utah State University, Plants, Soils, and Climate, Logan, Utah, United States
    A Life Filled with People, Plants, Photons, and Perseverance (15 mins)
  • Stephanie Burnett, University of Maine, School of Food and Agriculture, Orono, Maine, United States
    Impact on Sensor Automated Irrigation and Student Mentoring (15 mins)
  • Rhuanito Ferrarezi, University of Georgia, Horticulture, Athens, Georgia, United States
    The Man Behind the Legend (15 mins)
  • Andrew Ogden, University of Georgia, Griffin, Georgia, United States
  • Shuyang Zhen, Texas A&M University, United States
    The Light He Shined: Translating Plant Physiology into Smart Lighting Control Strategies (15 mins)
  • Leonardo Lombardini, University of Georgia, Horticulture, Athens, Georgia, United States
    Honoring Marc's Legacy (15 mins)

Moderator
JB

Jennifer Boldt

Research Horticulturist, United States Department of Agriculture
NM

Neil Mattson

Cornell University
MY

Melanie Yelton

GrowBig Consulting
Melanie Yelton, Dr. Yelton leverages over 25 years of plant science leadership to guide controlled agriculture entities towards climatically resilient food systems. Via her consultancy company, GrowBig, she advises controlled environment agriculture farms, lighting partners and R... Read More →
Speakers
Thursday September 26, 2024 4:00pm - 6:00pm HST
Nautilus 1

4:00pm HST

Interest Group Session: Using AI in Teaching: Examples and Methods
Thursday September 26, 2024 4:00pm - 6:00pm HST
As Artificial Intelligence (AI) continues development at a rapid pace, our current teaching and learning methods are also swiftly transforming. AI itself is often combined with various technologies such as image recognition, virtual reality (VR), machine learning, adaptive learning algorithms, and gamification. With the merger of existing technology, AI and education will change the way we teach as well as how students learn. Some examples for teaching Horticulture, Landscape Architecture or Plant Science include individualized teaching, deep learning, adaptive learning environments, AI-based assessment and image recognition. In this Professional Interest Group Session speakers will provide examples of how they are using AI in their teaching methods, followed by an open discussion with the audience that should provide additional examples and applications.

Coordinator(s)
  • Kathryn Orvis, Purdue Univ, Horticulture and Landscape Architecture, West Lafayette, Indiana, United States
Speaker/Participant(s)
  • Mary Rogers, University of Minnesota, Department of Horticultural Science, St Paul, Minnesota, United States
    How to Incorporate Generative AI in Teaching a Writing Intensive Urban Agriculture Course (15 mins)
    Summary:
  • Aaron Thompson, Purdue University, Horticulture and Landscape Architecture, West Lafayette, IN, United States
    Teaching with AI in Landscape Architecture (15 mins)
    Summary:
  • Cynthia Haynes, Iowa State University, Horticulture, Ames, Iowa, United States
    Potential benefits and pitfalls of using AI software in Horticulture teaching. (15 mins)
    Summary:

Moderator
KO

Kathryn Orvis

Professor, Purdue Univ
Speakers
Thursday September 26, 2024 4:00pm - 6:00pm HST
Coral 1

4:15pm HST

PGR 2 - Controlling growth of Brunnera macrophylla L. ‘Jack Frost’ with Uniconazole Substrate Drenches or Sprays
Thursday September 26, 2024 4:15pm - 4:30pm HST
Heartleaf brunnera (Brunnera macrophylla L.) is a popular herbaceous perennial that is often used in the landscape. With large leaves and a mounding habit, growth control is often needed during greenhouse production. Plant growth regulators (PGR) applied as substrate drenches or foliar sprays can control growth necessary to produce compact, high-quality containerized plants. Our objectives were to evaluate the efficacy and growth control provided by uniconazole substrate drenches or sprays. Rooted liners of heartleaf brunnera ‘Jack Frost’ were transplanted into containers (16.6-cm; 2.8 L) filled with a commercially formulated peat-based substrate. After 10 d, eight single-plant replicates received either a substrate drench or foliar application of uniconazole. For substrate drenches, 296-mL aliquots of solution containing deionized water (0 mg·L–1; control) or 0.25, 0.875, 1.75, 2,5, 5.5, 7.5, or 10.0 mg·L–1 uniconazole were applied across the substrate surface. For foliar sprays, 0, 2.5, 5.0, 7.5, 10.0, or 20.0 mg·L–1 uniconazole were applied at a rate of 1.89 L/ 9.29 m2. Plants were grown in a glass-glazed greenhouse at 23 °C under ambient daylight supplemented with a photosynthetic photo flux density of ≈120 µmol·m–2·s–1 delivered from light-emitting diode lamps from 0600 to 2200 HR (16-h photoperiod) to achieve a daily light integral of 14 mol·m–2·d–1. At 7 weeks after treatment, data were collected and plants were destructively harvested. In general, uniconazole significantly controlled plant height, diameter, and dry mass for each uniconazole application method. Plant height and diameter were 15% to 51% (2.2 to 7.6 cm) shorter and 22% to 40% (7.4 to 13.5 cm) smaller, respectively, than untreated plants as uniconazole drench concentration increased from 0.875 to 5.0 mg·L–1, respectively. Plants treated with 0.875 to 5.0 mg·L–1 developed 3 to 7 fewer leaves. Shoot dry mass was 39.5% lower than untreated plants as uniconazole drench concentration increased from 0.875 to 5.0 mg·L–1, respectively. For foliar applications, plant height and diameter were both reduced but to varying degrees. Plant height was reduced by 6% (~1 cm) but the greatest amount of control observed was in plant diameter which was reduced by 15 to 21% (4.8 to 7.2 cm) as concentrations increased from 5.0 to 10.0 mg·L–1. Collectively, these results indicate that drenches of 0.875 to 5.0 mg·L–1 uniconazole or foliar sprays of 5.0 to 10.0 mg·L–1 uniconazole may be used to control growth of ‘Jack Frost’ heartleaf brunnera.
Speakers
WR

William Rich

The Ohio State University
Co-authors
GO

Garrett Owen

The Ohio State University
Thursday September 26, 2024 4:15pm - 4:30pm HST
South Pacific 4

4:30pm HST

PGR 2 - Uniconazole Substrate Drenches Control Growth of Buddleia Cultivars
Thursday September 26, 2024 4:30pm - 4:45pm HST
The increasing diversity of butterfly bush (Buddleia × hybrida) cultivars presents new challenges for growers, particularly in adjusting plant growth retardants (PGRs) to manage plant size effectively. Therefore, the objective of this study was to evaluate uniconazole substrate drench concentrations for growth control of two popular cultivars of butterfly bush (Buddleia × hybrida). Liners of ‘Grand Cascade’ and ‘Prince Charming’ butterfly bush were individually transplanted into containers (16.5-cm; 1.7 L) filled with a commercially formulated bark-based substrate. After 10 d, eight single-plant replicates received a substrate drench of 266-mL aliquots of solution containing deionized water (0 mg·L–1; untreated) or 0.25, 0.5, 1, 2, or 4 mg·L–1 uniconazole. Plants were grown in a glass-glazed greenhouse at 20 °C under ambient daylight supplemented with a photosynthetic photo flux density of ≈125 µmol·m–2·s–1 delivered from light-emitting diode arrays from 0600 to 2200 HR (16-h photoperiod) to achieve a daily light integral of 14 mol·m–2·d–1. At 5 weeks after drench, data were collected. Plant height, plant diameter, growth index (GI), and shoot dry weights were unaffected by cultivar or cultivar × uniconazole concentration interaction but varied by uniconazole concentration (P < 0.0001); therefore, all data were pooled and analyzed by uniconazole concentration. Increasing uniconazole substrate drench concentrations effectively controlled ‘Grand Cascade’ and ‘Prince Charming’ butterfly bush plant height, plant diameter, GI, and shoot dry weights. Plant height and diameter were 16% to 32% (6.9 to 13.8 cm) shorter and 10% to 24% (6.9 to 16.9 cm) smaller than untreated plants as uniconazole drench concentration increased from 1 to 4 mg·L–1, respectively. Shoot dry mass was 24% to 34% (5 to 7 g) lower than untreated plants as uniconazole drench concentration increased from 1 to 4 mg·L–1, respectively. Overall, these results indicate that 1 to 4 1 to 4 mg·L–1 uniconazole applied as a substrate drench may be used to control growth of ‘Grand Cascade’ and ‘Prince Charming’ butterfly bush. Time to visible bud and flower was not negatively influenced by increasing uniconazole concentrations; however, growers should trial drench concentration and adjust as needed for desired market dates. Additionally, further investigations with uniconazole are warranted for other butterfly bush cultivar introductions because it is the is the preferred PGR for perennial growth control.
Speakers
LW

Lark Wuetcher

The Ohio State University
Co-authors
GO

Garrett Owen

The Ohio State University
Thursday September 26, 2024 4:30pm - 4:45pm HST
South Pacific 4

4:44pm HST

Temperate Tree Nut Crops/Horticultural Plant Reproductive Biology (NUTS/HPRB)
Thursday September 26, 2024 4:44pm - 5:25pm HST
Composted Pecan Shells: A Potential Growing Media Amendment For Container Grown Pecan Seedlings In Georgia - Srijana Thapa Magar
Oil and Dormex® improve bloom and yield in pistachios by driving metabolite changes - GURREET BRAR
Identifying the association between self-fertility and floral reproductive morphology in macadamia - Palakdeep Kaur
Pecan sap flow properties in a micro-irrigated Southeastern orchard - M. Y. Leclerc
Moderator
PK

Palakdeep Kaur

Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland (UQ)
I am pursuing Ph.D. from the University of Queensland, Australia. I started in October 2022 and have successfully finished my candidature confirmation. I did my Bachelors in Agriculture specialisation in Plant Breeding, Genetics and Biotechnology from India. I did my Masters in Agriculture... Read More →
Thursday September 26, 2024 4:44pm - 5:25pm HST
South Pacific 3

4:45pm HST

NUTS/HPRB - Composted Pecan Shells: A Potential Growing Media Amendment For Container Grown Pecan Seedlings In Georgia
Thursday September 26, 2024 4:45pm - 4:55pm HST
Pecan (Carya illinoinensis) production in Georgia holds significant economic importance nationally. It is an energy-intensive practice with a very low output-to-input ratio. Pecan byproducts, notably pecan shells and husks, account for up to 49% of the nut but are underutilized. A greenhouse experiment was conducted at the USDA facility in Byron, Georgia in 2023 to study the feasibility of composted pecan shells as a growing media amendment for container-grown pecan seedlings. The composted pecan shell was collected from a local pecan grower’s three-year-old composted pile, while fresh goat manure was sourced from the Fort Valley State University’s farm. Various ratios (25, 50, 75, and 100%) of composted pecan shells, along with biochar, goat manure, and chicken manure, were compared to a commercial soil mix (control). All the growing amendments underwent steam sterilization at 98°F for a couple of hours to eliminate any potential contaminants such as weeds, bacteria, fungi, and parasites. Each treatment combination was placed in individual floats to sow the one-year-old stratified ‘Elliott’ seeds. Once the seedlings developed two juvenile leaves, they were transferred to 3-gallon pots to evaluate further soil and plant physiological parameters. The treatments were arranged in a randomized complete block design with four blocks, each containing one treatment combination. Various soil and plant parameters were evaluated monthly, including soil electrical conductivity and temperature, plant size, photosynthesis, stem water potential, and chlorophyll content, to assess the impact of soil amendments on soil and pecan seedling growth. Results determined that composted pecan shell outperformed others in terms of germination (~80%), while none of the seeds germinated in any chicken manure treatment combination. Remarkably, the growth performance of pecan seedlings under different pecan shell ratios was comparable to those grown in commercial soil mix, biochar, and goat manure, indicating good plant health. The stem water potential values overall ranged above -6 Bar, suggesting no signs of plant water stress throughout the study. However, the 100% goat manure treatment consistently showed seedlings with significantly lower chlorophyll content and photosynthetic activity, leading to the smallest plant size compared to the control and biochar treatments. These findings highlight the potential of composted pecan shells as a sustainable soil amendment for container-grown pecan seedlings, offering a novel approach to repurpose pecan byproducts to enhance soil quality, promote sustainable agriculture practices, and serve as an additional income source to pecan growers, thus contributing to the economic viability of pecan production in Georgia.
Speakers
ST

Srijana Thapa Magar

Kentucky State University
Co-authors
Thursday September 26, 2024 4:45pm - 4:55pm HST
South Pacific 3

4:45pm HST

PGR 2 - Effects of Weather Conditions on the Efficacy of ACC as a Peach Thinner
Thursday September 26, 2024 4:45pm - 5:00pm HST
1-aminocyclopropane-1-carboxylic acid (ACC) is the immediate precursor of ethylene in plants. Accede SG containing ACC as active ingredient has been registered as a chemical thinner in the US for stone fruit and apple. The objective of this study was to investigate the effects of weather parameters on Accede SG efficacy. In a series of experiments in Oregon and California in the field and growth chambers, we evaluated the relationship between flower/fruitlet abscission caused by ACC and weather parameters in peaches. In field trials, ACC at 300 mgL-1 and 600 mgL-1 was sprayed on a daily basis to different set of peach trees throughout the bloom period and correlated fruit set data with daily weather parameters. From these field trials, it became apparent that flower/fruitlet abscission caused by ACC is in negative relationship with daily minimum and maximum temperatures. These findings were confirmed by greenhouse studies where increase in nighttime temperature reduced thinning efficacy of ACC. No close relationship between thinning efficacy and relative humidity was found. We created three models to predict ACC thinning efficacy using weather parameters and ACC spray concentration.
Speakers
JR

Jozsef Racsko

Valent USA
Co-authors
AK

Al Kovaleski

University of Wisconsin-Madison
NA
AK

Alec Karayan

Fresno State University
NA
GB

Gurreet Brar

Fresno State Univ.
NA
PF

Poliana Francescatto

Valent BioSciences LLC.
NA
SM

Steven McArtney

Valent BioSciences LLC.
NA
Thursday September 26, 2024 4:45pm - 5:00pm HST
South Pacific 4

4:45pm HST

Engaging those who fund our work, a job for all horticultural scientists
Thursday September 26, 2024 4:45pm - 6:00pm HST
Sponsored by National Issues Committee
Our work in horticulture is made possible to a great extent by Federal funding. That funding will only be available if Congress continues to value the work that we do with it. Therefore, all ASHS members should regularly let their representatives know how the funds are helping in your state or district. This session provides an understanding of how to confidently and effectively contact your Congressional district office about the value of programs that you know and use. This program is designed to be of particular value to members in the Western US, who are not likely to come to Washington DC for policy discussion.

This session will be a panel discussion to understand the perspective from the various offices involved and how they interact. The panel includes the actual people involved in this Congressional district.
  • Kendra Oishi, District Chief, Office of U.S. Representative Jill Tokuda, Hawaii 2nd District.
  • Anthony Ching, Director of Federal Relations for the University of Hawaiʻi System.
  • Thomas Björkman, ASHS National Issues Committee and Cornell University
  • Russell Galanti, Extension Educator, University of Hawaiʻi.
Moderator
TB

Thomas Bjorkman

Professor, CALS Horticulture
Speakers
KO

Kendra Oishi

District Chief, Office of U.S. Representative Jill Tokuda
AC

Anthony Ching

Director of Federal Relations, University of Hawaiʻi System
RG

Russell Galanti

Extension Educator, University of Hawaiʻi
Thursday September 26, 2024 4:45pm - 6:00pm HST
Coral 2

4:55pm HST

NUTS/HPRB - Oil and Dormex® improve bloom and yield in pistachios by driving metabolite changes
Thursday September 26, 2024 4:55pm - 5:05pm HST
Lack of dormant chilling is a major problem in producing pistachio trees in locations with warm periods during the winter time. In the past years, some locations in California have received insufficient winter chilling which has led to late bloom and crop reduction. Horticultural oil has been used as a rest-breaking agent to promote bud break and improve production. However, there is limited information regarding the merit of chill portion spray timing and the physiological mechanism behind bloom advancement by oil application. In the present study, three locations in California, North (Colusa County), Central (Madera County) and South-Western Fresno County (Cantua Creek) were selected for oil spray applications while Hydrogen cyanamide (Dormex®) was sprayed at Cantua Creek site. Tree of cv. Kerman (female) and Peters (male) on UCB-1 rootstock were sprayed with horticultural oil (IAP 440) @ 6% v/v or Dormex @4% at various chill portion (CP) accumulation milestones. Bloom period from bud swell to full bloom, tree yield, yield components, non-structural carbohydrates and macro and micro nutrients in buds and bark of pistachio shoots were analyzed. NMR-based metabolomics analysis was conducted to investigate the changes in metabolic profiles induced by exogenous oil or Dormex® application. Results showed that oil spraying in two southern locations advanced bud break but not in the northern site showing each location respond to oil spray differently. In Cantua site, Dormex® and oil spray at CP55 could significantly increase the yield while in Madera, oil spray at CP59 showed the highest yield. Results also showed that oil spray at different CPs and Dormex® could change the trend of soluble sugars and starch in bark and bud of pistachio trees. In Cantua, Dormex® significantly increased nitrogen (N), phosphorous (P), sulfur (S), boron (B), copper (Cu) and zinc (Zn) mobilization towards bud swell. Moreover, oil spray increased N, P, S in all CPs at all locations. A multivariate analysis conducted to compare the metabolite changes in control samples of bark and bud with these two rest-breaking agents led to the identification of nine metabolites that show a significant change in at least one of the comparisons (Creatine, Aspartate, Sucrose, Asparagine, Succinate, Fumarate, Leucine, Adenosine, and Uridine). It seems that oil and Dormex® applications can significantly increase the yield of pistachio trees by advancing bud break, improving bloom synchrony and also, by changes in carbohydrate, nutrients and metabolite changes in bark and bud of pistachio tree.
Speakers
GB

GURREET BRAR

california state university
Co-authors
FH

Faranak Hadavi

california state university
NA
MK

Masood Khezri

MR Institute
NA
VK

Vishvanathan Krishnan

california state university
NA
Thursday September 26, 2024 4:55pm - 5:05pm HST
South Pacific 3

5:00pm HST

PGR 2 - Mode of Action and Uptake Investigations of ACC as a Peach Thinner
Thursday September 26, 2024 5:00pm - 5:15pm HST
1-aminocyclopropane-1-carboxylic acid (ACC) is assumed to cause flower abscission via the ethylene pathway when used as a chemical thinner in peaches. The objectives of this study were to investigate the uptake of ACC via flower parts, and determine if ethylene is the main cause of flower abscission by ACC. In a series of field trials in Oregon, we determined that ACC is a non-mobile compound when applied as a foliar spray to peach trees. ACC does not translocate between branches and movement of externally applied ACC is very limited even between flower parts. When the ACC solution was applied via paintbrush to various parts of the flowers, it became evident that for sufficient flower thinning activity, the presence/uptake of ACC is needed through the pedicel and/or Abscission Zone tissues of the pedicel (AZ1-2). Application of ACC to the petals only, resulted in petal drop only but not in flower abscission. When evaluating the mode of action of ACC, we established a close relationship between ethylene production of the flowers and flower abscission. However, when ethylene production of the flowers was reduced with the addition of ACC oxidase inhibitors (2-picolinic acid, pyrazinecarboxylic acid) in the ACC spray solution, the flower abscission rate remained the same as in the ACC application alone. These results indicate that ethylene might not be the only factor in flower abscission caused by ACC.
Speakers
JR

Jozsef Racsko

Valent USA
Co-authors
PF

Poliana Francescatto

Valent BioSciences LLC.
NA
Thursday September 26, 2024 5:00pm - 5:15pm HST
South Pacific 4

5:05pm HST

NUTS/HPRB - Identifying the association between self-fertility and floral reproductive morphology in macadamia
Thursday September 26, 2024 5:05pm - 5:15pm HST
Self-fertility, the ability of a plant to set fruits with self-pollen, is an important commercial trait in many crops. Self-fertility has the potential to set fruits in the absence of pollinators and pollenisers. Most macadamia cultivars are self-infertile but a few exhibit degrees of self-fertility. The potential morphological factors underpinning variability in this trait have not been previously investigated in macadamia. Therefore, this study aimed to determine whether floral reproductive morphology differs among self-fertile and self-infertile cultivars. Pistil length (PL), stamen length (SmL) and stigma-anther distance (SAD) were measured from cultivars within a self-fertile and a self-infertile group for two flowering seasons. The analysed self-fertile cultivars were ‘HAES 741’, ‘HAES 791’, ‘A38’, ‘Q’, ‘K’ and ‘UQM40’, while the self-infertile cultivars were ‘HAES 344’, ‘A16’, ‘Daddow’, ‘D4’ and ‘A268’. There was no significant difference between years for any of the traits (P>0.05). However, significant differences were found between the self-fertile/self-infertile groups and among cultivars within groups for the three examined traits (P
Speakers
PK

Palakdeep Kaur

Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland (UQ)
I am pursuing Ph.D. from the University of Queensland, Australia. I started in October 2022 and have successfully finished my candidature confirmation. I did my Bachelors in Agriculture specialisation in Plant Breeding, Genetics and Biotechnology from India. I did my Masters in Agriculture... Read More →
Co-authors
BT

Bruce Topp

Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland (UQ)
NA
KM

Ky Mathews

Department of Agriculture and Fisheries, Nambour, Australia
NA
MC

Max Cowan

Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland (UQ)
NA
MA

Mobashwer Alam

Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland (UQ)
NA
Thursday September 26, 2024 5:05pm - 5:15pm HST
South Pacific 3

5:15pm HST

NUTS/HPRB - Pecan sap flow properties in a micro-irrigated Southeastern orchard
Thursday September 26, 2024 5:15pm - 5:25pm HST
Amazingly, in contrast with other crops and in stark contrast to their tree crop counterparts in the Southwest, little is known regarding the response of pecan trees to their environment in the Southeast. Surprisingly, few studies have been carried out regarding the response of pecan trees to factors influencing their response to variable such as vapor pressure deficit, water availability and other environmental variables. This paper reports on tree sap flow properties in a micro-irrigated pecan orchard near Hawkinsville, GA in 2022 and 2023. Results presented describe the diurnal trend in the sap flow behavior. The paper also reports how the timing of the peak in sap flow density in relation to solar radiation, vapor pressure deficit and temperature. It also reports on the intraseasonal variability and changes in sap flow density throughout the growing season. The daily patterns of sap flow through the day along with their accompanying hysteresis loops and implications for water management are discussed. The hysteretic strength for the sub-diurnal sap flow density against the vapor pressure deficit for the Southeastern pecan is quantified using a hysteresis index. Tree transpiration for these southern pecan trees is also discussed. This new data regarding sap flow properties in pecan trees shed useful insight on how trees respond to environmental conditions in a micro-irrigated orchard in the Southeast.
Speakers
ML

Monique Leclerc

Regents Professor, The University of Georgia
Co-authors
GZ

Gengsheng Zhang

The University of Georgia
NA
LW

Lenny Wells

University of Georgia
NA
Thursday September 26, 2024 5:15pm - 5:25pm HST
South Pacific 3

5:15pm HST

PGR 2 - Physiological Mechanism of Silicon’s Enhancement of Drought and Heat Tolerance in Creeping Bentgrass
Thursday September 26, 2024 5:15pm - 5:30pm HST
Creeping bentgrass is an important cool-season turfgrass species widely used for golf course putting greens, however it experiences summer stress and quality decline in the U.S. transition zone and other regions with similar climates. Silicon (Si) may improve abiotic stress of creeping bentgrass, but mechanism of its impact on plant drought and heat tolerance has not well understood. The objectives of this study were to investigate physiological mechanism of Si on tolerance to drought and heat stress in creeping bentgrass under growth chamber and field conditions. The five treatments from two Si products (Potassium silicate at 0.95 and 1.91 mL m-2, and Ortho-Si at 0.16 and 0.32 mL m-2) were applied biweekly to creeping bentgrass, and treated grass was subjected to heat and drought stress for 56 days and also the treatments were applied to creeping bentgrass putting green in the field conditions. Turfgrass quality, physiological parameters and root growth characteristics were evaluated biweekly. Deficit irrigation was applied to induce drought stress in June and July in the field plots. Foliar application of the Si products improved turf quality, photochemical efficiency, leaf chlorophyll and carotenoid content, antioxidant enzyme activity and endogenous Si content. The Si treatments at the high rates also improved root biomass, length, surface area, volume, and root viability when compared to the control. The results from the field study confirmed the findings in the growth chamber study. The exogenous Si may improve drought and heat tolerance by enhancing root growth and viability, Si uptake by roots, and up-regulation of antioxidant activity, protecting photosynthetic function. The results of this study suggest that foliar application of Si products may be considered as an effective approach to improve turf quality and physiological fitness of creeping bentgrass during the summer months in the U.S. transition zone and other regions with similar climate.
Speakers
XZ

Xunzhong Zhang

Virginia Tech
Co-authors
JG

James Goatley

Virginia Tech
NA
Thursday September 26, 2024 5:15pm - 5:30pm HST
South Pacific 4

5:30pm HST

PGR 2 - Effect of Light Quality and Intensity on Cannabis Photosynthetic Activity
Thursday September 26, 2024 5:30pm - 5:45pm HST
Among numerous abiotic environmental factors, varying light quality and intensity elicit photosynthetic responses that can play vital roles in the optimization of crop production in controlled environment agriculture. Earlier and preliminary studies on photosynthetic activity reported that amber light (595 nm) induces higher photosynthetic rates and quantum yield of plants is a wavelength-dependent response. To resolve the most accurate ePAR curves in cannabis (Cannabis sativa), this study investigated the spectral response of photosynthesis by examining the effects of the leaf versus the whole plant on the impact of photosynthetic activity. A customized CO2 chamber equipped with relative humidity, temperature, and CO2 was used to collect leaf and whole plant photosynthetic data from 5 week old clones with different monochromatic wavelengths (380–750 nm) using the LI-6800 Portable Photosynthesis System (LI-COR) equipped with the Large Leaf and Needle Chamber (LI-COR 6800-13). Differences and correlation between photosynthetic activity at the leaf level and the whole plant were determined. Subsequent studies will involve the combinations of different wavelengths at different ratios. Findings will expand the current understanding of the photosynthetic response of plants to light and provide highly resolved spectral quantum yield curves.
Speakers
PW

Philip Wiredu Addo

McGill University
Co-authors
AR

AnneSophie Rufyikiri

McGill University
NA
ML

Mark Lefsrud

McGill University
NA
MD

Mohamed Debbagh

McGill University
NA
SM

Sarah MacPherson

McGill University
NA
Thursday September 26, 2024 5:30pm - 5:45pm HST
South Pacific 4

5:45pm HST

PGR 2 - Enhancing the quality of novel greenhouse crops through dynamic LED lighting
Thursday September 26, 2024 5:45pm - 6:00pm HST
The adoption of supplemental lighting in horticulture has allowed greenhouse growers to increase the yield of multiple crops by at least 10%, with a 300% yield increase documented for cucumbers when transitioning from unlit to lit production. Since then, horticultural lighting has advanced significantly to now include dynamic LED lighting, which provides unparalleled control over the light intensity, spectrum and zoning within the greenhouse. This has allowed greenhouse growers to further maximize crop productivity, but also to target improvements in crop quality and to diversify their production. For example, the greenhouse industry has seen the introduction of multiple berry crops, leafy crops, Asian cucumbers, etc. in recent years, all of which have varying lighting requirements ranging from 12 to 25 mol of light per square meter per day. The ideal spectrum also differs between crops, as do the light saturation points and target intensities. Beyond enhancing photosynthesis and increasing crop productivity, dynamic LED lighting can also be used to improve the nutritional quality and taste of various crops through spectral adjustments during the growth cycle. In a trial comparing the impact of broad and narrow spectra on basil, a broad spectrum produced a flavor profile stronger in eucalyptol whereas a narrow spectrum produced an estragole-dominant crop. This resulted in a milder flavor under a broad spectrum and a stronger flavor under a narrow spectrum. With dynamic lighting, growers can adjust the spectrum to target different flavors and thus different markets. Further, the application of high levels of blue light during the last week of production has been repeatedly shown to enhance the antioxidant capacity of red leafy greens through the bioaccumulation of anthocyanin. The Brix, or sweetness, of fruiting crops has also been improved under dynamic lighting, with commercial trials showing a minimum of 7% increase in Brix in speciality cherry tomatoes compared to fixed spectrum lighting. This increase could potentially be enhanced with end-of-day (EOD) light treatments, which early trials have suggested to enhance the translocation of sugars from leaves to fruit. As such, dynamic LED lighting can improve both the productivity and nutritional quality of greenhouse crops, allowing forward-thinking growers to meet the growing population’s needs in terms of both quality and quantity.
Speakers
RS

Rose Seguin

Agronomist, Sollum Technologies
Rose Séguin is an agronomist specializing in controlled environment agriculture, with previous experience in indoor agriculture, agricultural innovation systems, and agricultural development in remote areas of Canada. She holds a bachelor's degree in agro-environmental sciences and... Read More →
Thursday September 26, 2024 5:45pm - 6:00pm HST
South Pacific 4

6:00pm HST

Social Event for ASHS Northern Region
Thursday September 26, 2024 6:00pm - 7:00pm HST
Members of the ASHS Northern Region are invited to join us for a social gathering/networking event.
Speakers
JL

Justin Lombardoni

Chicago Botanic Garden
Thursday September 26, 2024 6:00pm - 7:00pm HST
Hibiscus 1

6:00pm HST

Trivia Night/Competition Award Ceremony
Thursday September 26, 2024 6:00pm - 7:30pm HST
Don't miss this fun event!
Test your horticultural knowledge against other teams for a night of fun and camaraderie! 4 players per team allowed. You can join as a team, or sign up as an individual and we will team you up.

Sign up here.

Awards for the student and early career competitions will be presented between rounds of trivia.
Moderator Speakers
avatar for Shital Poudyal

Shital Poudyal

Extension Specialist, Utah State University
Shital Poudyal is an Assistant Professor and Ornamental Horticulture Specialist at the Department of Plants, Soils & Climate at Utah State University. He aims to develop best management practices for efficient irrigation of landscape nursery plants, identify and promote unconventional... Read More →
Thursday September 26, 2024 6:00pm - 7:30pm HST
Coral 3
 
Friday, September 27
 

7:00am HST

Speaker Ready Room - Friday
Friday September 27, 2024 7:00am - 12:00pm HST
Friday September 27, 2024 7:00am - 12:00pm HST
Sea Pearl 1-2

7:30am HST

Registration Open - Friday
Friday September 27, 2024 7:30am - 12:00pm HST
Friday September 27, 2024 7:30am - 12:00pm HST
Coral Lounge

8:00am HST

ASHS Presidential Address and Annual Business Meeting
Friday September 27, 2024 8:00am - 9:00am HST
Speakers
EF

Esmaeil Fallahi

University of Idaho
Professor
DL

Daniel Leskovar

ASHS President-Elect
avatar for Dean Kopsell

Dean Kopsell

Associate Dean, University of Georgia
I am the current ASHS President.
Friday September 27, 2024 8:00am - 9:00am HST
Coral 3

8:00am HST

ASHS Conference Central - Friday Hours
Friday September 27, 2024 8:00am - 12:00pm HST
Friday September 27, 2024 8:00am - 12:00pm HST
Coral 4/5

8:00am HST

Exhibit Hall Hours - Friday
Friday September 27, 2024 8:00am - 12:00pm HST
Friday September 27, 2024 8:00am - 12:00pm HST
Coral 4/5

9:00am HST

Keynote Speaker: Kerry Kakazu
Friday September 27, 2024 9:00am - 9:45am HST
"Vertical Farming in Hawaiʻi: Design Considerations for our Unique Environment"

Kerry Kakazu, PhD is the President of MetroGrow Hawaii, the first vertical farm in the state. He has a masters and PhD in Plant Physiology from the University of California at Davis. After a career in academia doing research, teaching and administration he combined his interests in plant science, technology and the local food scene to create MetroGrow Hawaii in 2014. The farm has been providing premium leafy greens to local restaurants and gourmet markets since its founding and is now exploring ways to expand vertical farming to significantly increase food self-sufficiency and security in Hawaiʻi.
Speakers
Friday September 27, 2024 9:00am - 9:45am HST
Coral 3

9:44am HST

Genetics and Germplasm 3 (GG 3)
Friday September 27, 2024 9:44am - 11:15am HST
Transcriptomic responses underlying host-pathogen interactions between resistant and susceptible Prunus accessions and two Armillaria Root Rot fungi - Stephen Parris
Fine mapping of Linkage Group 7 (LG7) Eastern Filbert Blight (EFB) Resistance in Hazelnut - Rion Mooneyham
Estimation of Breeding Values to Improve Kernel Weight in Almond (Prunus dulcis) - Shashi Goonetilleke
Alternative RNA Splicing Associated with Pecan Dichogamy - Xinwang Wang
Alaska Can Grow More Than Giant Vegetables: The Potential of Rhubarb for Specialty Crop Producers - Carol Miles
Utilization of Germplasm to Improve Illinois Horseradish - Alan Walters
Moderator
SG

Shashi Goonetilleke

The University of Queensland
Friday September 27, 2024 9:44am - 11:15am HST
Coral 1

9:45am HST

GG 3 - Transcriptomic responses underlying host-pathogen interactions between resistant and susceptible Prunus accessions and two Armillaria Root Rot fungi
Friday September 27, 2024 9:45am - 10:00am HST
Armillaria root rot (ARR) caused by Desarmillaria caespitosa and Armillaria mellea represents the main cause of premature stone fruit and nut tree decline in the United States. A. mellea is a primary concern for almond and peach growers in California, while D. caespitosa threatens peach production in the southeast region of the U.S. These fungi survive as facultative necrotrophs and colonize roots of several agriculturally important crops, including peach, almond, and sweet cherry. This colonization ultimately kills the woody roots and therefore host, severely limiting the tree’s lifespan and ability to provide a return on investment for the grower. Few management options are available to slow down ARR disease progression, and no management practice eliminates ARR fungi presence in an infested field. Additionally, most of the commercially available rootstocks are susceptible to infection, with only two peach/plum hybrid commercial rootstocks (Prunus umbellata × P. persica ‘MP-29’ and P. cerasifera × P. persica ‘Krymsk® 86’) showing partial resistance to ARR. The shared plum genetic background in these hybrids, paired with the lack of ARR resistance observed in peach germplasm suggests the source of resistance originated from plum. In this work, induced genetic responses in one susceptible accession, P. persica ‘Guardian®’, and two resistant accessions, P. cerasifera ’14-4’ and ‘MP-29’, when infected with D. tabescens and A. mellea were analyzed. Additionally, expression of genes encoding effectors and cell wall degrading enzymes (CWDEs) were investigated in the ARR fungi while infecting the three hosts. The results of the infection assays revealed unique responses between each of the three hosts in their progression of disease symptoms over time and in their transcriptomes while under infection by the two ARR fungi. Analysis identified key hub genes expressed by the two resistant Prunus accessions involved in the sensing and enzymatic degradation of chitin and the upregulation of GSTs, oxidoreductases, and transcription factors. Investigation of the ARR fungi transcriptomes similarly identified host-dependent expression of fungal effectors and CWDEs responsible for degrading the cell wall components cellulose, hemicellulose and pectin. Comprehensive analyses considering transcriptomes produced by both the host and pathogen during the infection course provides a deeper understanding of the factors driving resistant and susceptible responses to ARR infection, and their effects on the infecting pathogen’s gene expression.
Speakers
SP

Stephen Parris

Clemson University
Co-authors
CS

Christopher Saski

Clemson University
NA
GS

Guido Schnabel

Clemson University
NA
JW

Jared Weaver

Clemson University
NA
JA

Jeffrey Adelberg

Clemson University
NA
KG

Ksenija Gasic

Clemson University
LC

Lichun Cai

Clemson University
NA
Friday September 27, 2024 9:45am - 10:00am HST
Coral 1

9:59am HST

Tropical Horticultural Crops (TROP)
Friday September 27, 2024 9:59am - 10:45am HST
Advancing Cocoa Yield Forecasting in Ecuador Using Machine Learning and Field Data Integration - Daniel Mancero
Maturity Stage at Harvest Modulates Fruit Softening and Quality of Jackfruit - Zor Singh
Growing Papaya in Mississippi - Guihong Bi
Moderator
GB

Guihong Bi

Mississippi State University
Friday September 27, 2024 9:59am - 10:45am HST
Lehua Suite

9:59am HST

Organic Horticulture 3 (ORGH 3)
Friday September 27, 2024 9:59am - 11:30am HST
Biostimulants Promoted Onion Plant Growth and Helped Mitigate Drought Stress During the Seedling Stage - Genhua Niu
Effluent of the Anaerobic Digestion of Food Waste as a Biofertilizer for Red Cabbage - Roland Ebel
Optimizing the Application of Anaerobic Soil Disinfestation in Organic High Tunnel Vegetable Production Systems - Francesco Di Gioia
Cover Crops Potential for Regulating Soil Moisture and Temperature in Drive-row of an Irrigated Organic Vineyard - Mehdi Sharifi
Apple Rootstocks Affect Soil Rhizosphere Microbial Communities and Root Exudate Composition - Julie Cardon
No-till planting organic dry bean into rolled-crimped cover crops - Matthew Ryan
Moderator
FD

Francesco Di Gioia

Pennsylvania State University
Friday September 27, 2024 9:59am - 11:30am HST
South Pacific 3

9:59am HST

Consumer Horticulture and Master Gardeners 2 (CHMG 2)
Friday September 27, 2024 9:59am - 11:45am HST
Evaluating Knowledge Gained from Extension Education Provided in a Citizen-Science Gardening Project - Celina Gomez
Using Citizen Science to Evaluate Cultivar Preferences of Compact Tomato Plants - Michael Fidler
Extension Master Gardeners and Pollinator Research: The Challenges and Benefits - Pam Bennett
Utilizing Facebook and Instagram to Distribute a Residential Horticultural Needs Assessment - Claude Judy Jean
Exploring the Ethical Viewpoints of Proplifiting Among Consumers - Leandria Garrett
Consumer Perceptions of Climate-Smart Products - Abigail Lauterbach
Setting Priorities for Managing Extension Work and Home Life - Esther McGinnis

Moderator
avatar for Esther McGinnis

Esther McGinnis

Extension Horticulturist/Director of the Extension Master Gardener Program, North Dakota State University
I am the Extension Horticulturist and Director of the Extension Master Gardener Program.
Friday September 27, 2024 9:59am - 11:45am HST
South Pacific 1

9:59am HST

Growth Chambers and Controlled Environments 7 (CE 7)
Friday September 27, 2024 9:59am - 11:45am HST
Foliar Nutrient Concentrations of Strawberry Mother and Daughter Plants Grown in Controlled Environments - Jennifer Boldt
Increasing Nutrient Solution Electrical Conductivity Increases Vegetative Growth of Strawberry - Erin Yafuso
Impact of Artificial Chilling on Yields of Indoor-Propagated Strawberry Plants in California, Florida, and North Carolina - Ibraheem Olamide Olasupo
The Nitrate to Ammonium Ratio Impacts Strawberry Runnering and Daughter Plant Number - Erin Yafuso
Effect of Monosilicic Acid on Growth and Physiology of Lettuce - Seunghyun Choi
Light Intensity and Zinc Biofortification Effect on Yield and Nutritional Quality of Pea and Radish Microgreens - Pradip Poudel
Evaluation of Liquid Organic Fertilizers for Containerized Production of Leafy Greens in a Controlled Environment - Uttara Samarakoon
Moderator
JB

Jennifer Boldt

Research Horticulturist, United States Department of Agriculture
Friday September 27, 2024 9:59am - 11:45am HST
Nautilus 1

9:59am HST

Vegetable Crop Management 6 (VCM 6)
Friday September 27, 2024 9:59am - 11:45am HST
Field-Based Remediation Strategies for Groundwater Nitrogen Contamination
Can Healthy Soil Make Healthy People? Investigating The Impact Of Soil Biota On Micronutrient Uptake In Vegetable Crops
Optimizing nitrogen fertilizer concentrations in vegetable transplant production
Growing Resilient Broccolini: Harnessing Clover Living Mulch for Weed Suppression and Yield Enhancement
Foliage Removal on Processing Sweet Corn Reduces Yield Most Strongly Near Tasseling
Optimizing Planting Density of Sweet Corn in Georgia
Boosting Sweet Corn Yields: The Power of Biochar and Fertilizers Unveiled
Moderator
HM

Hayley Milner

University of Georgia
Friday September 27, 2024 9:59am - 11:45am HST
South Pacific 2

9:59am HST

Weed Control and Pest Management 4 (WCPM 4)
Friday September 27, 2024 9:59am - 11:45am HST
Can Multi-species Cover Crops and Beneficial Microbes be Utilized for Soil Borne Pathogen Management in Watermelon? - Sukhman Kaur
Evaluation of Celery Breeding Lines and Commercial Cultivars for Resistance to Fusarium oxysporum f.sp. apii Race 2 and Race 4 - Christopher Greer
Directed Energy System: A Non-chemical Approach for the Management of Nematodes, Pathogens, and Weeds in Nurseries - Tatiana Benedetti
Sweetpotato-associated Virome in Mississippi - Sead Sabanadzovic
Evaluation of Insecticide Application Plan to Manage Thrips for Sweet Onions in Texas - Subas Malla
Are selective insecticides compatible with Bemisia tabaci biocontrol efforts in controlled environments? - Arash Kheirodin
Plants Under Regulation; A North Carolina Perspective - Jarred Driscoll
Moderator
SS

Sead Sabanadzovic

Mississippi State University
Friday September 27, 2024 9:59am - 11:45am HST
South Pacific 4

9:59am HST

Floriculture 3 (FLOR 3)
Friday September 27, 2024 9:59am - 12:00pm HST
Multiple Foliar Applications of Ethephon for Growth Control of Lantana Camara - Lark Wuetcher
Ethephon Substrate Drenches Control Growth of Containerized Annual Bedding Plants and Herbaceous Perennials - William Rich
Microbial Communities in the Vertical Profile of a Container Substrate - Silvia Valles Ramirez
Moisture Content Effects Microbial Activity in Substrates Derived from Five Different Hammermilled Wood Species Over the Course of Greenhouse Petunia Production - Amanda Mizell
Stratification significantly reduces the phytotoxic effects of fresh hardwood - Andre Truter
The Use of Machine Learning to Develop Refined Foliar Tissue Analysis Standards and Diagnostic Tools for for Petunia - Patrick Veazie
Increasing the Nighttime Lighting Duration Can Hasten Flowering of Long-day Plants -Qingwu Meng
Extended Storage of Cut Flowers Using Sub-zero Temperature - John Dole
Moderator
JD

John Dole

North Carolina State University
Friday September 27, 2024 9:59am - 12:00pm HST
Kahili

10:00am HST

CE 7 - Foliar Nutrient Concentrations of Strawberry Mother and Daughter Plants Grown in Controlled Environments
Friday September 27, 2024 10:00am - 10:15am HST
Few published studies provide foliar tissue nutrient concentrations for strawberry (Fragaria × ananassa) mother and daughter plants. Recommendations primarily focus on tissue concentrations for field-grown plants during fruit production. As controlled environment production of strawberry increases, a need exists to define tissue nutrient concentration ranges for healthy foliar tissue, for both vegetative and fruit production. Defining deficient, sufficient, and toxicity ranges will assist growers in selecting nutrient solution recipes and correcting nutritional issues that arise. The objective of this study was to identify nutrient concentration ranges for healthy strawberry mother and daughter plants grown in controlled environments. Foliar tissue samples were collected from two separate experiments: 1) ‘Albion’, ‘Fronteras’, and ‘Monterey’ grown in a peat-based substrate, and 2) ‘Monterey’ grown indoors in deep water culture. Plants received a modified strawberry nutrient solution (Yamazaki) that provided 100 mg·L-1 nitrogen (N). The percent total N provided as ammonium (NH4 ) ranged from 0% to 40% in both experiments. Plants did not exhibit any visual symptoms of foliar nutrient deficiencies or toxicities. Foliar tissue from mother (n=72) and daughter plants (n=144) were collected and analyzed individually. Nutrient concentration ranges comprised the middle 75% of plant samples (12.5% – 87.5% quantiles). Mother plant macronutrient concentrations ranged from 2.12%–2.64% nitrogen (N), 0.53%–1.23% phosphorus (P), 2.05%–3.88% potassium (K), 2.01%–3.36% calcium (Ca), 0.33%–0.56% magnesium (Mg), and 0.14%–0.28% sulfur (S). Daughter plant foliar macronutrient concentrations ranged from 2.18%–3.38% N, 0.49%–0.92% P, 2.20%–4.19% K, 1.01%–3.03% Ca, 0.31%–0.53% Mg, and 0.15%–0.30% S. Mother plant foliar micronutrient concentrations ranged from 158–233 mg·kg-1 boron (B), 1.5–5.6 mg·kg-1 copper (Cu), 57–587 mg·kg-1 iron (Fe), 131–384 mg·kg-1 manganese (Mn), and 11–29 mg·kg-1 zinc (Zn). Daughter plant foliar micronutrient concentrations ranged from 69–212 mg·kg-1 B, 1.2–4.5 mg·kg-1 Cu, 56–347 mg·kg-1 Fe, 78–315 mg·kg-1 Mn, and 18–36 mg·kg-1 Zn. In general, these macro- and micronutrient ranges overlap between mother and daughter plants. These values represent a first step in developing and refining foliar nutrient ranges for strawberry mother and daughter plants in controlled environments.
Speakers
JB

Jennifer Boldt

Research Horticulturist, United States Department of Agriculture
Co-authors
EY

Erin Yafuso

United States Department of Agriculture
Friday September 27, 2024 10:00am - 10:15am HST
Nautilus 1

10:00am HST

CHMG 2 - Evaluating Knowledge Gained from Extension Education Provided in a Citizen-Science Gardening Project
Friday September 27, 2024 10:00am - 10:15am HST
A citizen-science gardening project was conducted in 2023 with 300 participants from Indiana, Iowa, and Tennessee, who were recruited to compare three cultivars of compact tomato (Solanum lycopersicum) plants in an 18-week experiment. The study used a pre- and post-test format where participants were asked 15 questions that assessed their confidence levels about pest management, healthy cooking, and safe handling and preservation of home-grown tomatoes. Monthly educational sessions were delivered virtually by Extension faculty at Land-grant institutions from each state, covering the aforementioned topics. The pest-management session was the most popular with 81 live participants and 207 views of the video recording. This was followed by the healthy-cooking session with 67 live participants and 129 views. Participation and views of the last session that focused on safe handling and preservation were lower (58 live participants and 43 views), likely attributed to decreases in engagement throughout the project, or due to relevancy, as not all gardeners engage in produce preservation. At the end of the project, 224 participants completed questions from both surveys enabling an evaluation of knowledge gained. Overall, a positive increase in mean scores was measured across all questions, indicating that participants gained knowledge from the Extension programing provided. The largest knowledge increases were observed for pest-management questions, ranging from 6% to 20%. Most other questions had an increase of 1% to 8%, except those pertaining to knowledge about the use of canning and freezing methods, and food-safety practices for preservation, with 16% and 13% increases, respectively. The largest differences in confidence levels between pre- and post-test responses were found in questions about implementing control strategies for garden pests, using eco-friendly pest management methods, and reducing food waste, for which “very confident” responses changed from 10% to 82%, 14% to 76%, and 11% to 41%, respectively. Similarly, for all three questions, “not very confident” responses decreased from an average of 12% to 0%. However, there was a shift in confidence for a question regarding food-safety practices for preservation, with “very confident” responses decreasing from 57% to 35% and “not very confident” responses increasing from 0.5% to 5%. This suggests participants may have overestimated their knowledge initially. Our findings demonstrate the positive impact of Extension education on gardening-related knowledge and highlight the value of collaboration between university researchers, Extension faculty, and stakeholders as citizen scientists.
Speakers
CG

Celina Gomez

Purdue University
Co-authors
CH

Cynthia Haynes

Iowa State University
KM

Karen Mitchell

Purdue University
NA
MF

Michael Fidler

Purdue University
NB

Natalie Bumgarner

University of Tennessee
Friday September 27, 2024 10:00am - 10:15am HST
South Pacific 1

10:00am HST

FLOR 3 - Multiple Foliar Applications of Ethephon for Growth Control of Lantana Camara
Friday September 27, 2024 10:00am - 10:15am HST
Lantana (Lantana camara) is a popular annual bedding plant among consumers because it is heat tolerant and attracts pollinators with its vibrant and often multi-colored flowers. Greenhouse growers commonly apply plant growth regulators (PGRs) to control lantana growth and produce a compact, well-branched, and flower. Introduction of new lantana cultivars instigates review of previously known PGR recommendations. As such, the objective of this study was to evaluate the effectiveness of multiple foliar spray applications of ethephon [(2-chloroethyl) phosphonic acid] to control growth and stimulate branching of lantana ‘Bandana Red’. Unrooted cuttings of lantana were received from a commercial propagator and stuck into 105-cell plug trays (30-mL individual cell) filled with a propagation mix. Cuttings were propagated for 35 d under 23 °C air temperature, 24 °C root-zone heating, and a daily light integral of 12 mol·m–2·s–1. Rooted liners were transplanted into individual containers (11.4-cm; 600 mL) filled with a commercial peat-based substrate. Beginning 7 d after transplant, eight single-plant replicants received 1 to 3 foliar spray applications on a weekly basis containing 0 (control; deionized water), 250, 500 or 750 mg·L–1 ethephon. Plants were grown in a glass-glazed greenhouse at 20 °C under ambient daylight supplemented with a photosynthetic photon flux density of ≈125 µmol·m–2·s–1 delivered from LED arrays from 0600 to 2200 HR (16-h photoperiod) to achieve a daily light integral of 12 mol·m–2·d–1. At 42 d after transplant, plants were destructively harvested, and data collected. In general, multiple foliar spray applications with increasing ethephon concentrations affected lantana plant height, diameter, branch number, and shoot dry weight to different magnitudes. For example, lantana plant height was suppressed by 21% to 39% (12.7 to 9.7 cm) from 250 to 750 mg·L–1 ethephon, respectively, compared to untreated plants and were more compact as applications increased. Plant diameter decreased by 13% to 19% (25.5 to 23.7cm) compared to untreated plants as concentration increased from 250 to 750 mg·L–1, respectively, and as spray applications increased. A similar trend was observed for branch number and shoot dry weight. Overall, multiple foliar spray applications of 250 to 750 mg·L–1 ethephon can control the growth of lantana ‘Bandana Red’; however, growers will need to conduct in-house trials to evaluate the level of control desired. Further studies investigating the effects of multiple foliar spray applications with increasing concentrations of ethephon on additional lantana cultivars are warranted.
Moderator
LW

Lark Wuetcher

The Ohio State University
Co-authors
GO

Garrett Owen

The Ohio State University
Friday September 27, 2024 10:00am - 10:15am HST
Kahili

10:00am HST

GG 3 - Fine mapping of Linkage Group 7 (LG7) Eastern Filbert Blight (EFB) Resistance in Hazelnut
Friday September 27, 2024 10:00am - 10:15am HST
Eastern filbert blight (EFB) disease caused by the fungal pathogen Anisogramma anomala (Peck) E. Müller is a major threat to Oregon’s hazelnut (Corylus avellana) industry. The Oregon State University (OSU) hazelnut breeding program has used ‘Gasaway’ as a source of resistance in many releases. Cultivars with ‘Gasaway’ resistance mapped to linkage group 6 (LG6) including ‘Jefferson’ and ‘McDonald’ have been extensively planted throughout Oregon’s Willamette Valley over the past decade. However ,‘Jefferson’ and ‘McDonald’ have exhibited small cankers in commercial orchards under high disease pressure. In New Jersey, cultivars with ‘Gasaway’ resistance develop large cankers. Thus, there are concerns about the long-term durability of ‘Gasaway’ resistance and the sustainability of Oregon’s hazelnut industry. The disease is also a main limiting factor to commercial hazelnut production in the eastern USA. New sources of resistance would be interesting, and a few major resistance genes have been mapped to LG7. Four populations were developed for fine mapping the LG7 resistance region using the ‘Ratoli’ (from Spain) and OSU 1166.123 (from Sochi, Russia) resistance sources. SSRs narrowed the resistance region to < 20 cM, and recombinant individuals were identified using 4-5 SSR loci within the region. Recombinants were inoculated with Anisogramma anomala in the greenhouse and in the field, and disease was evaluated 18 months later. A set of 22 new SSR markers were developed from di- and tri-nucleotide repeats between the flanking markers in the ‘Jefferson’ genome (v4). SSR markers were characterized using a diversity panel of 50 hazelnut accessions. To develop KASP/PACE primers for SNPs in the region, an initial set of 3000 SNPs was reduced to 100 using a SNP array. High density genetic linkage maps with new SSR and KASP markers were constructed for all four mapping populations. The results of this study will aid marker-assisted selection and the breeding of EFB-resistant cultivars with these new sources, and facilitate the pyramiding of R-genes in a single clonal selection for more durable resistance.
Speakers
RM

Rion Mooneyham

Oregon State University
Co-authors
JS

Jacob Snelling

Oregon State
NA
SM

Shawn Mehlenbacher

Oregon State University
Friday September 27, 2024 10:00am - 10:15am HST
Coral 1

10:00am HST

ORGH 3 - Biostimulants Promoted Onion Plant Growth and Helped Mitigate Drought Stress During the Seedling Stage
Friday September 27, 2024 10:00am - 10:15am HST
Climate change and global warming are increasing the frequency of drought incidents, which negatively impact crop production. Onion is one of the major vegetable crops produced in Texas, which requires a long growth period and prone to drought stress as it has shallow roots and needs frequent irrigation. Plant biostimulants may offer a potential solution to mitigate drought stress in onion production. This study investigated the effect of different biostimulants (no application as control, Kelpak, Spectrum DS, MycoApply, and Tribus Continuum) on onion seedling growth under well-watered and drought stressed (50-60% field capacity) conditions. Results showed that there was no significant interaction between biostimulants and drought stress on most of the parameters we collected. All biostimulants significantly increased shoot weight, leaf area, plant height, and root weight compared to the control. Notably, Spectrum DS, MycoApply, and Kelpak specifically enhanced root morphology by increasing root length, root area, and root volume compared to the control. But the application of biostimulants didn’t significantly affect average root diameter or the number of root tips. Drought stress significantly reduced the growth of onion seedlings across all measured parameters, except for the number of root tips, compared to the well-watered group. While drought stress caused a 36.9% decrease in shoot fresh weight, application of Kelpak, Spectrum DS, MycoApply, and Tribus Continuum increased shoot fresh weight by 29.8 to 34.9%, partly offsetting the growth reduction and alleviating the stress experienced by the seedlings. In conclusion, the application of the investigated biostimulants shows promise for enhancing drought tolerance in onion seedlings.
Speakers
GN

Genhua Niu

Texas A
Co-authors
Friday September 27, 2024 10:00am - 10:15am HST
South Pacific 3

10:00am HST

TROP - Advancing Cocoa Yield Forecasting in Ecuador Using Machine Learning and Field Data Integration
Friday September 27, 2024 10:00am - 10:15am HST
Accurate prediction of cocoa yields is critical for farmers, governments, and industry as it influences logistics and supports decision-making. In tropical agriculture, there has been a recent trend toward integrating sensor technology, data science, and machine learning to enhance management and boost crop production. However, cocoa yield prediction models rely on the quality and availability of public datasets and genetic differences among cocoa genotypes. Moreover, current cocoa models require technical skills for satellite image processing or a significant investment in sensors and software. Different statistical models in cocoa predict yield independently of physiological processes or disease pressure. Therefore, we propose a mechanistic model that uses historical yield and weather data from 2010 to 2023 and the in-field sampling from 61 orchard plots from four farms in Guayas, Ecuador. Time series measures of cocoa pods and disease incidence per tree in the plots were recorded for the 2023 and 2024 growing seasons. Cocoa pod counts and diseased pods, as well as tree photographs for biomass calculation, were recorded using a customized mobile application. Ecuador´s cocoa production in this location has a bimodal annual distribution, with the highest peak following the start of the rainy season. Moniliasis disease also presented the highest incidence within the next two months of precipitaion peaks. Several varieties of cocoa are grown in Ecuador, but production is dominated by two main groups: Fine cocoa or national flavor and CCN-51. The national type of cocoa is characterized by its unique flavor profile. However, it is prone to diseases and has a lower yield. To overcome these challenges, our study aims to develop a machine learning-based model geared towards Ecuador's distinct national type cocoa varieties, taking into account local climate patterns, soil characteristics, biomass, and direct cocoa pod field counting. The analysis reveals that cocoa yield variability is affected mainly by moniliasis disease incidence, tree biomass, and environmental factors such as temperature, solar radiation, and precipitation. In contrast, soil texture, pH, and electrical conductivity had minor variations and a negligible effect on yield changes. The proposed model was compared with other machine learning algorithms based on Mean Absolute Error and Mean Square Error. The validation phase, employing the Mean Absolute Percentage Error, indicates our model's substantial predictive accuracy with a confidence interval of 73.4 percent at the 0.1 significance level and confirms the model's effectiveness in forecasting cocoa yields under Ecuadorian conditions.
Speakers
DM

Daniel Mancero

UNIVERSIDAD AGRARIA DEL ECUADOR
Fruit researcher with experience in multidisciplinary projects for plant protection and plant breeding
Co-authors
MA

Maritza Aguirre

UNIVERSIDAD AGRARIA DEL ECUADOR
NA
NV

Nestor Vera

UNIVERSIDAD AGRARIA DEL ECUADOR
NA
YG

Yoansy Garcia

UNIVERSIDAD AGRARIA DEL ECUADOR
NA
Friday September 27, 2024 10:00am - 10:15am HST
Lehua Suite

10:00am HST

VCM 6 - Field-Based Remediation Strategies for Groundwater Nitrogen Contamination
Friday September 27, 2024 10:00am - 10:15am HST
Agricultural pollutants are commonly detected in Wisconsin groundwater samples, particularly in areas with coarse-textured soils and high input agriculture. Practical and effective techniques are needed to reduce contaminants in agricultural leachate to protect human health and the nearby environment. Organic soil additives may be able to capture excess nitrogen fertilizer in the soil and prevent groundwater contamination with minimal grower expense. Five soil additives were tested in soil columns for nitrogen fertilizer capture ability. Two biochar treatments, two papermill waste treatments, and one humic acid treatment was tested against an untreated control. Leachate volume remained constant among treatments, but biochar and papermill waste treatments reduced nitrogen content in leachate (up to 8.5% and 35%, respectively). Humic acid was ineffective at reducing nitrogen content in leachate in an abiotic system, prompting a second soil column experiment currently underway that includes live potato plants. Intercropping systems may also be able to reduce agricultural pollutants in groundwater. Potatoes were intercropped with adjacent strips of fall-planted winter rye, spring-planted winter rye, and spring-planted yellow mustard to investigate the effects of companion crops on potato yield compared to a monoculture potato control plot. Intercropping did not impact potato yield or size distribution compared to monoculture potato. A second intercropping study was designed to explore potato yield when companion crops were planted directly in the furrow between each potato row. Treatments included a spring-planted winter rye and a spring-planted yellow mustard, seeded at three intervals post hilling, with nitrogen fertilizer banded over the potato row or conventionally broadcast. Neither intercropping nor fertilizer application method affected potato yield. Further research is underway to test intercropping systems in other high-nitrogen vegetable crops such as sweet corn.
Speakers
ES

Emma Schmidt

University of Wisconsin- Madison
NA
Co-authors
DH

Daniel Heider

University of Wisconsin-Madison
NA
JS

Jacklyn Slivicke

University of Wisconsin-Madison
NA
JC

Jed Colquhoun

University of Wisconsin
Friday September 27, 2024 10:00am - 10:15am HST
South Pacific 2

10:00am HST

WCPM 4 - Can Multi-species Cover Crops and Beneficial Microbes be Utilized for Soil Borne Pathogen Management in Watermelon?
Friday September 27, 2024 10:00am - 10:15am HST
Watermelon is highly susceptible to soil borne pathogens, typically Fusarium oxysporum sp. Niveum (FON) that can lead to a yield loss of upto 60-80%. Out of the four pathogenic races of FON, race 2 is more prevalent in the Southeastern US on more than 60% of watermelon fields. Cover crops are known for improving soil health, diversity, and abundance of microorganisms, and reported to decrease Fusarium wilt (FW) disease severity by up to 20-60%. However, previous studies have only evaluated single species cover crops for its impact on FW in watermelon whereas for ecosystems services, multi-species cover crops are recommended. A greenhouse and field study were conducted with aims to determine the effects of multi-species cover crops and beneficial microbes in controlling FW in watermelon. The cover crop mixtures included in the studies were, mixture A: rye, oat, Austrian winter pea, crimson clover, hairy vetch; mixture B: oat, wheat, crimson clover, radish, turnip. The field study was conducted at two locations in upper coastal region of South Carolina. Periodic cover crop biomass was taken. At location one cover crop mixture A accumulated a fresh biomass of 1017.50 tons/ha as compared to mixture B (907.16 tons/ha), at 97 days after planting. On the other hand, at second field site, mixture A accumulated fresh biomass of (349.6.4 tons/ha) and fresh biomass weight of mixture B was (153.59 tons/ha) at 120 days after planting. This could be due to more sandy and poor soil conditions at second field site. Further we will evaluate the impact of different treatments on FW disease severity index, watermelon fruit yield and fruit quality parameters.
Speakers
SK

Sukhman Kaur

Clemson University
Co-authors
BJ

Bhupinder Jatana

Clemson University
TS

Tom Sanders III

Clemson University
NA
Friday September 27, 2024 10:00am - 10:15am HST
South Pacific 4

10:00am HST

Workshop: Preparing for AI in Postharvest Research
Friday September 27, 2024 10:00am - 12:00pm HST

Explore cutting-edge techniques, tools, and strategies to integrate artificial intelligence (AI) into postharvest research. Learn how AI can enhance data analysis, optimize storage conditions, and improve quality assessment for fruits and vegetables. During this workshop, we’ll delve into organizing datasets, determining the number of variables, and understanding their types. Join us to stay ahead in the rapidly evolving field of postharvest science. Join us for this dynamic workshop, where experts share insights, foster collaboration, and propel postharvest science into the future! 🌱

The goal of this workshop is to empower researchers, practitioners, and industry professionals with the knowledge and tools needed to revolutionize postharvest practices. By integrating artificial intelligence (AI) and non-destructive technologies, we aim to achieve the following objectives: 1. Enhanced Quality Control 2. Efficient Resource Management 3. Scientific Advancements 4. Sustainable Practices 5. Industry Transformation

Coordinator(s)
  • Randolph Beaudry, Michigan State University, Horticulture, East Lansing, Michigan, United States
  • Angelos Deltsidis, University of Georgia, Horticulture, Tifton, GA, United States
Moderator(s)
  • Angelos Deltsidis, University of Georgia, Horticulture, Tifton, GA, United States
Speaker/Participant(s)
  • Carolina Torres, Washington State University, Wenatchee, Washington, United States
    Introduction (10 minutes) Welcome and Objectives (10 mins)
    Summary: Overview of AI applications, emphasizing data analysis, optimization, and quality assessment and discuss principles for designing experiments that maximize AI potential.
  • Luan Oliveira, University of Georgia, Tifton, Georgia, United States
    Remote Sensing and AI (20 mins)
    Summary: Explore how remote sensing, combined with AI algorithms, accelerates data processing for fruits and vegetables.
  • Pavlos Tsouvaltzis, Southwest Florida Research and Education Center, University of Florida, United States
    Non-Destructive Technologies (20 mins)
    Summary: Delve into advanced non-destructive methods for assessing vegetable crop physiology, quality, and safety.
  • Loren Honaas, USDA ARS TFRL, United States
    AI in Molecular Biology (20 mins)
    Summary: Discuss molecular indicators related to postharvest tree fruit disorders using AI techniques.

Moderator Speakers
CT

Carolina Torres

Washington State University
RB

Randolph Beaudry

Michigan State University
Dr. Randolph Beaudry, Professor, MSU Department of Horticulture (MSc, PhD, University of Georgia). His appointment is 50% MSU Extension and 50% AgBioResearch. His research program includes both regional and international projects and focuses on the physiology of plant responses to... Read More →
Friday September 27, 2024 10:00am - 12:00pm HST
Coral 2

10:14am HST

Viticulture and Small Fruits 5 (VSF 5)
Friday September 27, 2024 10:14am - 12:15pm HST
Two Years, Three Genotypes, and Two Locations: Fruit Quality of Native and Cultivated Aroniaberry Grown in Georgia - Leynar Leyton
Prohexadione Calcium is an Effective, Dose Dependent Growth Retardant of ‘Osage’ Blackberry - Hannah Lepsch
Impacts of the ‘Fan’ Training Method on Blackberry Yield and Fruit Quality on the Rotating Cross-Arm Trellis - Lizzy Herrera
Evaluation of a Strawberry (Fragaria × ananassa) Cultivar Trial for Yield and Fruit Quality in Lubbock, Texas - Srijana Panta
Active vs. Passive Row Cover Management: Impacts on Abiotic Growing Conditions, Yield, and Pests on Overwintering Strawberry - Wenjing Guan
Performance of Containerized Strawberries (Fragaria x ananassa Duch.) in a Greenhouse Environment - Caroline Blanchard
Influence of Soil Disinfestation and Beneficial Bacterial Treatments on Anthracnose Fruit Rot Disease and Strawberry Yield - Jayesh Samtani
Effect of Temperature and Light during Cold Storage of Strawberry Liners - Lian Duron


Moderator
JS

Jayesh Samtani

Associate Professor, Virginia Tech
Friday September 27, 2024 10:14am - 12:15pm HST
Coral 3

10:15am HST

CE 7 - Increasing Nutrient Solution Electrical Conductivity Increases Vegetative Growth of Strawberry
Friday September 27, 2024 10:15am - 10:30am HST
Established guidelines for electrical conductivity (EC) for strawberry (Fragaria ×ananassa) fruit production exist for plants grown in soilless substrates. However, EC recommendations for strawberry mother plants may differ when the goal is prolific runnering instead of flowering and fruiting. Our objective was to evaluate the impact of EC concentration strawberry runner and daughter number. Strawberry ‘Monterey’ were grown in a greenhouse in 19.1-cm diameter pots filled with a soilless substrate (50 perlite : 25 coco coir : 25 peat). To formulate the EC treatments, all components of a strawberry nutrient solution (Yamazaki) increased equally, which corresponded to nitrogen (N) concentrations of 50, 100, 150, 200, 300, and 400 mg·L-1 N. After adding 0.8 mM potassium bicarbonate as a buffer and adjusting pH to 5.7, the final nutrient solution EC values were 0.9, 1.6, 2.3, 2.8, 3.9, and 4.9 mS·cm-1. After 12 weeks of treatment, runner and daughter plant number, morphological assessments, and mother plant leaf burn index were evaluated. The qualitative assessment of leaf burn utilized a 1 to 5 scale (1 = no tip burn; 2 = mild, margins of ≥ 3 leaves; 3 = moderate, necrosis on at least half of ≥ 3 leaves; 4 = moderate to severe, complete necrosis on ≥ 3 leaves; and 5 = severe, complete necrosis on ≥ 4 leaves and necrosis of daughter plants). Leaf burn values ranged from 1.6 ± 0.2 (± SE) in the 50 mg·L-1 N treatment to 5.0 ± 0.0 in the 400 mg·L-1 N treatment. Runner number exhibited a quadratic response and ranged from 2 ± 0 at 50 mg·L-1 N to 7 ± 1 at 300 mg·L-1 N. Daughter plant number also exhibited a quadratic response. It increased from 14 ± 3 at 50 mg·L-1 N to 44 ± 4 at 200 mg·L-1 N, then declined to 30 ± 13 at 400 mg·L-1 N. Total plant biomass (mother plant, stolons, and daughter plants) exhibited a quadratic relationship. It increased from 23.5 ± 4.0 g at 50 mg·L-1 N to 65.9 ± 7.9 g at 200 mg·L-1 N, then declined to 40.0 ± 5.2 g at 400 mg·L-1 N. Overall, the optimal nutrient solution EC range for strawberry mother plants was 100 to 200 mg·L-1 N (or 1.6 to 2.8 mS·cm-1). In this range, mother plants produced a high number of runners and daughter plants, with minimal leaf burn due to high substrate EC values.
Speakers
EY

Erin Yafuso

United States Department of Agriculture
Co-authors
JB

Jennifer Boldt

United States Department of Agriculture
Friday September 27, 2024 10:15am - 10:30am HST
Nautilus 1

10:15am HST

CHMG 2 - Using Citizen Science to Evaluate Cultivar Preferences of Compact Tomato Plants
Friday September 27, 2024 10:15am - 10:30am HST
Citizen science can be used as a research method to evaluate consumer preferences in horticulture. In 2023, 300 participants from Indiana, Iowa, and Tennessee were recruited to grow three cultivars of compact tomato (Solanum lycopersicum) plants started from seed or as transplants in an 18-week experiment. The cultivars evaluated were Cocoa, Red Robin, and Micro Tom. After completing a pre-experiment survey to characterize demographics and gardening experience levels, participants were provided with a plant kit containing all materials required to complete the experiment. Participant engagement was maintained using a social-media community page, monthly virtual educational sessions, and frequent email communications. At the end of the experiment, 203 participants had completed the post-experiment survey focused on evaluating cultivar and plant-type preferences. Furthermore, three focus group sessions with six random participants each were conducted to further assess survey responses. Cocoa was the preferred cultivar by 41% of participants, followed by Red Robin at 31%. Cultivar preferences of plants started from seed followed the same trend for appearance, fruit number, and fruit taste. However, growth and appearance of ‘Red Robin’ transplants were ranked higher than ‘Cocoa’. Approximately 70% of participants preferred plants started as transplants compared to those from seed, regardless of cultivar. These preferences were attributed to the higher yield, better growth and perceived fruit taste, and lower maintenance required to use transplants. Overall, 69% of participants reported they would be willing to pay between $1.00 to $7.49 more for a transplant of their favorite cultivar compared to currently available tomato plants at local nurseries. Findings from the focus group sessions indicated participants liked the potential gift-use of these compact cultivars, and their versatility to be used in different gardening spaces such as kitchen countertops or windowsills. Results from this study indicate potential consumers value appearance, fruit yield, and fruit taste when selecting compact tomato cultivars, whereas ease of care and plant growth are more important factors when choosing a plant type.
Speakers
MF

Michael Fidler

Purdue University
Co-authors
CG

Celina Gomez

Purdue University
CH

Cynthia Haynes

Iowa State University
KM

Karen Mitchell

Purdue University
NA
MK

Melinda Knuth

North Carolina State University
NB

Natalie Bumgarner

University of Tennessee
Friday September 27, 2024 10:15am - 10:30am HST
South Pacific 1

10:15am HST

FLOR 3 - Ethephon Substrate Drenches Control Growth of Containerized Annual Bedding Plants and Herbaceous Perennials
Friday September 27, 2024 10:15am - 10:30am HST
Containerized annual bedding plants and herbaceous perennials account for 57% of the 2020 U.S. floriculture market with a reported combined wholesale value of $3.2 billion. To produce high-quality, compact containerized ornamental plants, foliar spray applications and substrate drenches of plant growth regulators (PGRs) are often utilized. Ethephon [(2-chloroethyl) phosphonic acid] is a common PGR used to control growth, stimulate branching, and manipulate flowering, but is only labelled for foliar applications. Therefore, our objective was to evaluate the response of 35 floriculture species drenched with increasing concentrations of ethephon. Annual bedding plants and herbaceous perennials were received as unrooted cuttings and propagated at 23°C under 10 mol·m–2·s–1 for 21 or 28 d, respectively. Plants were transplanted into containers filled with a soilless substrate and grown in a glass-glazed greenhouse at 20°C under 14 mol·m–2·d–1. At 10 d after transplant, eight single-plant replicates received a substrate drench of 296-mL aliquots of solution containing 0 (control; deionized water), 25, 50, 75, 100, or 200 mg·L–1 ethephon for annuals or 0, 125, 250, 500, 750, or 1,000 mg·L–1 ethephon for herbaceous perennials. Plant growth metrics including height, diameter, shoot and root dry weight were determined 6 weeks after transplant. Time to flower was determined for select species by recording the date of anthesis for each plant. In general, plant height of annual bedding plants and herbaceous perennials were suppressed and shoot and root dry weight reduced as concentrations of ethephon increased. For example, petunia (Petunia × hybrida ‘Flame Red’) drenched with 200 mg·L–1 was ≈40% (5.8 cm) shorter than untreated plants. Similarly, in dahlia (Dahlia × hybrida ‘Dark Red’) height and diameter were decreased by 50% (15.4 cm) and 30% (12.4 cm), respectively as concentrations increased from 0 to 200 mg·L–1. In digiplexis (Digiplexis × hybrida), substrate drenches increasing from 0 to 1,000 mg·L–1 ethephon reduced shoot dry mass by ≈55% (17.1 g). Root dry weight of catmint (Nepeta faassenii) was reduced by 35% (1.54 g) as concentrations increased from 0 to 1,000 mg·L–1. Time to flower was unaffected at all concentrations of the species selected. These growth and development trends were reflected in most of the species evaluated. As such, this research demonstrates that ethephon, if labelled for substrate drenches, provides adequate growth control of floriculture crops.
Speakers
WR

William Rich

The Ohio State University
Co-authors
GO

Garrett Owen

The Ohio State University
Friday September 27, 2024 10:15am - 10:30am HST
Kahili

10:15am HST

GG 3 - Estimation of Breeding Values to Improve Kernel Weight in Almond (Prunus dulcis)
Friday September 27, 2024 10:15am - 10:30am HST
Improving nut and kernel quality traits is a high priority in almond breeding programs around the world. Almond has a long juvenile period and phenotypic selection for nut and kernel traits can only be conducted after three years from planting. In early stages of planting, individuals with desirable nut and kernel traits can be identified by marker-trait associations (MTAs) using molecular markers. Currently, MTAs are identified by quantitative trait locus (QTL) mapping using progeny from bi-parental crosses or association mapping panels. However, the efforts of identifying MTAs using current QTL detection methods are hampered either by unavailability of genomic information or required genetic linkage maps. In addition, most kernel traits have polygenic inheritance, and many genes and genomic regions affect genetic variations. In crop research, genomic selection would provide promising approach to accelerate the genetic gains and reduce the length of breeding cycle. Yet, application of genomic selection in almond breeding and research is limited. We present results demonstrating the predictive ability of whole-genome and pedigree-based models to identify elite candidate parents for almond kernel weight. In this work, we used ancestral pedigree and phenotypic data from 13,000 progeny that were derived from 57 parents and 291 families. Ancestral pedigrees were recorded from the available literature from the almond breeding programs in USA, Spain, Italy, France, and Australia. Average kernel weight was obtained for each progeny tree from 30 nuts. All parents were resequenced using whole-genome sequencing at a depth of 15x. Over 80k high quality, independent single-nucleotide polymorphisms were used to construct realised genomic relationship matrix and linkage disequilibrium (LD) regions were used to compute LD weights. Genomic best linear unbiased prediction (GBULP) using Asreml-R was used to predict genomic estimated breeding values (GEBV). Pedigree model derived from linear mixed model was used to predict individual tree effects (PEBV) to validate the predicted GEBVs. EBVs were compared using Pearson correlation coefficient (r) and elite candidate parents were selected based on the selection index. For kernel weight, both pedigree and genomic models resulted similar EBVs, and r was 0.97. A high level of correlation in EBVs obtained from two methods indicates the suitability of these models in estimating BVs for future predictions. Predicted elite candidate parents from this study can reduce the conventional breeding cycle of almond by 6 years. The constructed models mainly represent Australian context and multi-environmental trials are required to identify the broader applicability of these models.
Speakers
SG

Shashi Goonetilleke

The University of Queensland
Co-authors
CH

Craig Hardner

The University of Queensland
NA
MW

Michelle Wirthensohn

The University of Adelaide
NA
Friday September 27, 2024 10:15am - 10:30am HST
Coral 1

10:15am HST

ORGH 3 - Effluent of the Anaerobic Digestion of Food Waste as a Biofertilizer for Red Cabbage
Friday September 27, 2024 10:15am - 10:30am HST
Food and farm waste processed by anaerobic digestion (AD) generates a nutrient-rich digestate suitable for use as a biofertilizer. Small-scale AD systems production of biofertilizer offer an on-site solution accessible to individual households and small horticultural producers. Unlike common and more complex AD solutions, small-scale systems do not require extensive management or infrastructure investments. In 2022, we investigated the nutrient content and usability of digestate from two small-scale biodigester models: A commercially built digester with a 1,200 L digester tank, and a prototype we designed with a 114 L capacity. Locally sourced fresh raw cow milk served as inoculum. Over a span of 16 weeks, 12 randomly selected households in Bozeman, Montana, tested the two digester models, feeding them with the food waste they generated. Six of the households received the commercial model, and six tested the prototype. Digestate samples were collected biweekly to analyze their chemical properties and potential as a biofertilizer. After 16 weeks, we blended all digestate, taking equal parts from all household samples, and tested it in a greenhouse study as a fertilizer for red cabbage (Brassica oleracea L. Capitata Group) seedlings. In addition to a control treatment where no biofertilizer was used, we applied 40 ml of biofertilizer per plant in a “high dose treatment” and 20 ml biofertilizer per plant in a “low dose treatment.” Each treatment involved 50 cabbage plants growing individually in trays of 10 cm diameter. On a weekly interval, the biofertilizer was sprayed on the substrate, with amounts varying by treatment. The substrate consisted of loam soil, washed sand, Canadian sphagnum peat moss, perlite, vermiculite, and dolomitic lime. Seedlings were irrigated manually every second day. To ensure sufficient nitrogen supply, all three treatments received an initial application of 40 mL of fish emulsion per cabbage plant. No pest or disease management practices were implemented. After 30 days, all plants were harvested, and their aboveground dry biomass was measured. A trend towards higher aboveground dry biomass in the "high biofertilizer dose" treatment compared to the "low biofertilizer dose" and control treatments was observed. Additionally, the aboveground biomass underwent nutrient content analysis, revealing a tendency towards the highest potassium content in the "high dose treatment." This study showed that household food waste processed through small-scale AD systems generates valuable biofertilizer that can help manage crops’ nutrient needs.
Speakers
avatar for Roland Ebel

Roland Ebel

Research Associate, Montana State University
Roland Ebel has dedicated his professional life to the facilitation and the production of sustainable food. He counts with a PhD in Organic Farming, granted by the University of Natural Resources and Life Sciences Vienna. The thesis project was done in Gran Canaria, Spain, and dealt... Read More →
Friday September 27, 2024 10:15am - 10:30am HST
South Pacific 3

10:15am HST

TROP - Maturity stage at harvest modulates fruit softening and quality of jackfruit
Friday September 27, 2024 10:15am - 10:30am HST
The maturity stage at harvest influences the postharvest quality and storage life of fruit. Harvesting jackfruit (Artocarpus heterophyllus Lam.) at the optimum maturity stage is more important due to the very large size of the fruit. Therefore, the present investigation was conducted to determine the impact of four different maturity stages on physicochemical parameters and fruit-softening enzymes in two jackfruit genotypes (Accession 242 and Accession 341). Fruit for the initial three stages were harvested at 10 days intervals commencing 90 days after flowering (DAF), while fruit for the final stage were harvested based on traditional maturity parameters (142 and 153 DAF) in Accession 341 and Accession 242 respectively. Results indicated an increase in fruit size, seed and bulb weight with the advancement of fruit maturity in both accessions. Moreover, there was a concurrent decline in spine density and an increase in spine flatness with the progression of fruit maturity. Whilst pulp percentage increased, there was a decrease in rag and core percentage at advanced maturity stages. However, peel and seed percentage were not influenced significantly by the advancement of fruit maturity. Additionally, there was a decrease in L* value with a concomitant increase in a*, b*, and C* values of the bulb with the advancement of fruit maturity. In both accessions, bulb firmness, and moisture content were highest in fruit harvested at 90 DAF. The decline in bulb firmness was associated with higher activities of polygalacturonase, pectin methyl esterase, cellulase, and pectate lyase. In both accessions, soluble solid content (SSC), DPPH radical scavenging activity, total flavonoids, and ascorbic acid content were higher in fruit harvested during the last stages of maturity while titratable acidity and total phenolics content were comparatively lower in advanced maturity stages. These findings highlight that the earlier stages (90 and 120 DAF) are suitable as meat alternatives due to better texture, while the most favourable stages for fresh consumption are 142 ± 4.7 and 153 ± 5.7 DAF in ‘Accession 341’ and ‘Accession 242’ due to better colour, higher pulp percentage, higher SSC and antioxidant activity, respectively.
Speakers
ZS

Zora Singh

Foundation Professor Horticultural Science, Edith Cowan University
Zora Singh is a Foundation Professor Horticultural Science in the School of Science with noteworthy expertise in Production technology and Postharvest physiology of fresh horticultural produce, undergraduate teaching and research training to domestic and international MSc and PhD... Read More →
Co-authors
AW

Andrew Woodward

Edith Cowan University
NA
EA

Eben Afrifa-Yamoah

Edith Cowan University
NA
HM

Hafiz Muhammad Shoaib Shah

Edith Cowan University
NA
JK

Jashanpreet Kaur

Edith Cowan University
MS

Muhammad Sohail Mazhar

Department of Industry, Tourism and Trade
NA
Friday September 27, 2024 10:15am - 10:30am HST
Lehua Suite

10:15am HST

VCM 6 - Can Healthy Soil Make Healthy People? Investigating The Impact Of Soil Biota On Micronutrient Uptake In Vegetable Crops
Friday September 27, 2024 10:15am - 10:30am HST
The health of humans and ecosystems are closely interlinked, therefore fostering healthy soils may aid in addressing micronutrient deficiencies. Healthy soils are active with diverse microbial and mesofauna communities that carry out soil processes that are essential for crop growth and development. A greenhouse experiment was conducted to investigate the effect of soil mesofauna on micronutrient content in vegetable crops and determine if plant root structure or shifts in soil microbial community composition (relative pathogen abundance) impact these affects. Crop species (snap beans and beets), Collembola (Isotomiella minor) abundance (none, low, or high), and microbial community composition (native community and pathogen-dense community) treatments were imposed and replicated five times. The soil treatments were prepared by sterilizing soil and inoculating the soil with the two different microbial communities. The inoculated soil was placed in pots and one cup of compost was mixed into the top 5 cm. Snap beans and beets were planted at a depth of 2.5 cm and 0.25 cm, respectively. The Collembola treatments (none, 100 Collembola, 200 Collembola) were then added to the appropriate pots. Weekly checks were conducted to monitor plant health and growth. Once each crop reached maturity (approximately 60 days), a destructive harvest was conducted. Crop biomass and marketable yield fresh weights were recorded and I. minor abundance was verified at the harvest. Crop biomass samples were frozen for later analysis of minerals relevant to human health including essential nutrients (e.g., calcium, sodium, magnesium, potassium, iron, and zinc) and heavy metals (e.g., lead, cadmium, and arsenic). Minerals were extracted via microwave digestion in nitric acid and quantified via ICP-MS. We hypothesized that the concentration of micronutrients in the vegetables will increase as I. minor abundance increases, and that the I. minor will have a greater effect on the snap bean compared to the beets due to the greater root surface area. Additionally, we conjectured that a pathogen-dense microbial community will diminish the effects of I. minor on micronutrient uptake, since greater pathogen presence would likely decrease their direct interactions with crop roots. We found that the addition of I. minor enhanced crop growth regardless of soil microbial community composition. The beets were more sensitive to changes in soil microbial community composition compared to the snap beans. Our findings illustrate the importance of healthy soil biological communities for quality vegetable production.
Speakers
AJ

Ashley Jernigan

Assistant Professor, Virginia Tech
Co-authors
DC

Dennis Cladis

Virginia Tech
NA
Friday September 27, 2024 10:15am - 10:30am HST
South Pacific 2

10:15am HST

VSF 5 - Two Years, Three Genotypes, and Two Locations: Fruit Quality of Native and Cultivated Aroniaberry Grown in Georgia.
Friday September 27, 2024 10:15am - 10:30am HST
Aroniaberry or chokeberry (Aronia sp., Rosaceae) is an attractive new native fruit crop. Native to eastern and central United States, this deciduous tree-like shrub produces berries with one of the highest concentrations of anthocyanins compared to other fruits. Bred for northern climates, A. ‘Viking’ is the most popular fruit cultivar. Fruit production and quality of A. ‘Viking’, Red Chokeberry (A. arbutifolia), and black chokeberry (A. melanocarpa) was evaluated during the 2022 and 2023 growing seasons, in two locations in the state of Georgia: Blairsville (Zone 7a, Blue Ridge region) and Griffin (Zone 8a, Piedmont region). At both locations, 15 two-year old plants of each genotype were planted in 2021. All genotypes increased their yields between growing seasons (2022 to 2023) but the increment was much higher, and plants had higher yields in Blairsville. A. ‘Viking’ performed poorly in Griffin in 2022 (38.33 g and 119.4 average berries /plant) compared to plants in Blairsville (184.83 g and 237 average berries /plant); in 2023, Blairsville yields were 705.58 g and 1308 average berries /plant, but yields were almost zero in Griffin. A similar trend was observed in A. melanocarpa, with higher yields in Blairsville in the first year and no berry production in Griffin during the second year. A. melanocarpa was the genotype with the biggest increment in yield from 30.62 g and 21 average berries/plant in 2022 to 1111.41 g and 1594.95 average berries /plant in 2023 (Blairsville). A. arbutifolia had better yields in Blairsville compared to Griffin, but plants produced berries at both locations during both years. In terms of fruit quality, A. ‘Viking’ berries were tougher and with a stronger skin in Griffin, and there were no significant differences in texture from 2022 to 2023 in Blairsville. A. melanocarpa berries had similar texture and skin strength in both years. A. arbutifolia texture was similar in both locations in 2023, but in 2022 Griffin plants produced tougher fruit with stronger skin. Plants in Blairsville produced sweeter fruit compared to Griffin, across all genotypes.
Speakers
LL

Leynar Leyton

University of Florida
Co-authors
BP

Bodie Pennisi

University of Georgia
NA
CR

Carol Robacker

University of Georgia
NA
Friday September 27, 2024 10:15am - 10:30am HST
Coral 3

10:15am HST

WCPM 4 - Evaluation of Celery Breeding Lines and Commercial Cultivars for Resistance to Fusarium oxysporum f.sp. apii Race 2 and Race 4
Friday September 27, 2024 10:15am - 10:30am HST
Fusarium wilt of celery, caused by the soil-borne pathogen Fusarium oxysporum f. sp. apii (Foa), has been a persistent challenge for celery growers in California. Two races of the pathogen are documented in California. Foa race 2 was described in the 1970s and is widespread throughout celery-growing regions of California, typically causing yellowing and stunting of established plants, resulting in failure to produce marketable heads. Foa race 4 was identified in Ventura County in 2013 and by 2022 had displaced race 2 as the predominant race causing celery losses in Ventura County. Foa race 4 is more aggressive than race 2, often causing plant stunting and death within weeks after planting, particularly if soil temperature is 22ºC or higher. In support of celery breeding programs, USDA and University of California developed a collaboration to conduct resistance evaluation field trials. Trials were conducted in two coastal California locations naturally infested with Foa in 2022 and 2023: Santa Maria (race 2) and Camarillo (race 4). Cultivars and breeding lines from private companies and public germplasm collections were evaluated in replicated field plots. Plant mortality was assessed, and soil temperature was recorded during the growing season. At harvest, disease severity of internal symptoms of Fusarium wilt were scored from 0 (no visible symptoms) to 5 (severe crown decay) for a subset of plants from each plot. Each celery entry was assessed for petiole length, weight, petiole greenness, cracking, bolting, ribbiness, pithiness, and suckering for a subset of plants from each plot. At Santa Maria in 2022, there was minimal plant mortality, but most entries appeared susceptible with disease severity scores ranging from 2.0-3.6, indicating vascular symptoms in roots and crowns. Many entries did not produce marketable celery due to stunting. Entries exhibiting the most tolerance to Foa race 2 had disease severity scores of 0.1-0.7 and produced the heaviest stalks with the longest petioles. At Camarillo in 2022, daily mean air temperatures during the two weeks after planting were 24 to 27ºC, likely promoting rapid disease development of Foa race 4 and severe early decline in susceptible entries. Six weeks after planting, 23 of 42 entrees exhibited 80-100% plant mortality. However, five entries had disease severity scores of 1.0-1.5 and less than 15% mortality. These more tolerant lines produced marketable celery. These results contribute to the development of Foa-resistant breeding lines and inform growers about the performance of cultivars in local conditions.
Speakers
CG

Christopher Greer

University of California
Co-authors
AP

Alexander Putman

University of California, Riverside
NA
OD

Oleg Daugovish

University of California Cooperative Extension
RE

Renee Eriksen

USDA Agricultural Research Service
NA
Friday September 27, 2024 10:15am - 10:30am HST
South Pacific 4

10:30am HST

CE 7 - Impact of Artificial Chilling on Yields of Indoor-Propagated Strawberry Plants in California, Florida, and North Carolina
Friday September 27, 2024 10:30am - 10:45am HST
Unavailability of pathogen-free strawberry propagules in commercial quantities necessitates the development of a novel completely indoor precision propagation technology for the crop, which also seeks to reduce dependence on soil fumigants including methyl bromide. Artificial chilling of plug plants could also enhance transplant vigor, flowering, and yield of strawberry. Under this novel technology, strawberry tips which consisted of five short day (SD) cultivars (Fronteras, Camarosa, Chandler, Sensation and Brilliance) and one long day (LD) cultivar (Monterey) were collected from tissue cultured mother plants. Plants were propagated under completely controlled environment (CE) conditions in a plant factory. Strawberry daughter plants were rooted in 50 cc trays filled with a commercial substrate and were arranged in the controlled environment under 90 – 100 % humidity, 27 °C temperature, 80 – 100 µmol m-2 s-1 light (LED), 18 hours photoperiod, and fertigated using the ebb and flow technique for 28 days. Our hypothesis was that artificial chilling will improve plant vigor and yield of CE-propagated strawberry transplants. We therefore assessed the impact of 350 – 450 hours of artificial chilling on the plant performance and yield of the transplants in four different locations in the US. Monterey, Brilliance, and Sensation cultivars received 350 hours of chilling while Fronteras, Chandler, and Camarosa cultivars were chilled for 450 hours. Strawberry plug plants (chilled and no-chill) were planted in replicated field trials in California, Florida, and North Carolina. Camarosa and Chandler cultivars were transplanted in North Carolina, Fronteras in Southern California, Monterey in Central California, while Brilliance and Sensation were transplanted in Florida. Preliminary results show improved vigor and yield from chilled plants in Florida and North Carolina field trials, while no differences were observed in California. Final results of the study will be shared during the conference.
Speakers
avatar for Ibraheem Olamide Olasupo

Ibraheem Olamide Olasupo

Postdoctoral Research Scholar, North Carolina State University
Co-authors
CS

Calyssa Stevenson

North Carolina State University
NA
GH

Gerald Holmes

Cal Poly San Luis Obispo
NA
GF

Gina Fernandez

North Carolina State University
NA
MH

Mark Hoffmann

North Carolina State University
NA
OD

Oleg Daugovish

University of California Cooperative Extension
RH

Ricardo Hernandez

North Carolina State University
NA
SS

Samantha Simard

Cal Poly- San Luis Obispo
SA

Shinsuke Agehara

University of Florida
Friday September 27, 2024 10:30am - 10:45am HST
Nautilus 1

10:30am HST

CHMG 2 - Extension Master Gardeners and Pollinator Research: The Challenges and Benefits
Friday September 27, 2024 10:30am - 10:45am HST
Extension Master Gardeners (EMGs) have participated in a variety of citizen science projects providing new knowledge. This knowledge acquisition may not occur without the assistance of EMGs. Research projects that are focused on consumer horticulture challenges are not typically given a high priority by those who financially support scientific research in consumer horticulture. Therefore, researchers turn to EMGs as citizen scientists to assist with consumer horticulture research. In 2022, Ohio State University partnered with the Cincinnati Zoo and Botanic Garden, Dawes Arboretum, and Ohio EMGs to evaluate 10 cultivars of native plants to determine if they were attractive to pollinators. EMGs were tapped to monitor the cultivars and collect data on abundance and diversity of species. Thirteen Ohio counties with EMG programs were involved in this research along with the partners. The first year of data collection was a pilot year and the second year was the first year for data analysis. In this session you will learn about the steps involved in this research project as well as the challenges addressed and benefits to both the EMGs and the consumer. You will also learn about the results of the research.
Speakers
PB

Pam Bennett

State Master Gardener Program Director, Associate Professor, Ohio State University
Friday September 27, 2024 10:30am - 10:45am HST
South Pacific 1

10:30am HST

FLOR 3 - Microbial Communities in the Vertical Profile of a Container Substrate
Friday September 27, 2024 10:30am - 10:45am HST
A moisture gradient exists in containers filled with soilless substrates where the substrate is wetter at the bottom of the container and becomes drier towards the top of the container. This moisture gradient affects other substrate chemical properties and therefore may affect biological properties including the microbial communities present. Microbial communities in soilless substrates have only recently been studied and little is known about their uniformity throughout the container. This research aimed to evaluate how the bacterial and fungal portions of the microbial community may change along the vertical profile of a container substrate. A substrate was mixed that consisted of manure compost, peat moss, and perlite (20:65:15 v/v) and planted with a single sunflower seedling. After 0, 3, and 6 weeks in a greenhouse environment, samples of soilless substrate from the top, middle, and bottom of the container (approx. 4.3 cm depth for each layer) were collected for DNA extraction. Bacterial and fungal communities were characterized by sequencing PCR amplified 16s rRNA genes and ITS regions, respectively. We found that the phyla Pseudomonadota, Bacteriodota, and Ascomycota were present throughout the container profile in all three layers. However, bacterial genera Paucibacter, Pseudomonas, and Iodophanus, and fungal genera Cercophora and Mortierella differed in abundance within each layer. Pseudomonas tolerant to negative abiotic factors were greater in the bottom layer after 6 weeks. Likewise, Coprinellus , responsible for lignin and cellulose degradation, was also present only in the bottom layer. The diversity of bacterial communities differed between layers, with the greatest in the middle and the lowest in the top layer. The percentages of all bacterial amplicon sequence variants (ASVs) that were shared among the three layers at 3 and 6 weeks were only 16% and 28%, respectively. The diversity of fungal communities was less affected by layer and time, but the percentages of shared fungal ASVs among layers were still only 27% and 28% at 3 and 6 weeks, respectively. In consequence, it is necessary to consider sampling technique and location when collecting a DNA sample from a container substrate.
Speakers
SV

Silvia Valles Ramirez

Ohio State University
NA
Co-authors
FM

Frederick Michel

Ohio State University
NA
JP

Jelmer Poelstra

Ohio State University
NA
Friday September 27, 2024 10:30am - 10:45am HST
Kahili

10:30am HST

GG 3 - Alternative RNA Splicing Associated with Pecan Dichogamy
Friday September 27, 2024 10:30am - 10:45am HST
Pecan (Carya illinoinensis), a North American native nut crop, exhibits two distinct flowering habits where male and female flowering occur at separate times. Trees that shed pollen before their pistillate flowers become receptive are classified as protandrous or type 1 (recessive homozygous, pp), while those with pistillate flowers receptive before pollen shed are protogynous or type 2 (dominant heterozygous, PP/Pp). Establishing commercial pecan orchards requires planting both types of pecan cultivars to ensure optimal pollination for maximum production. To investigate critical genes associated with pecan heterodichogamous flowering, we collected tissues from four stages (dormant buds, swollen buds, immature catkins, and immature pistils) of three genotypes (PP, Pp, and pp). Paired-end RNA sequencing at 125/150 bp read lengths was conducted on an Illumina platform. Clean and unique reads were mapped to an annotated 'Pawnee’ reference genome. Out of 32,267 annotated genes, over 5,000 (~15%) were identified to have alternative splicing events associated with pecan flowering dichogamy. We illustrate by three genes that present significant alternative splicing patterns associated with dichogamy genotypes, distinguishing the pp genotype from PP and Pp genotypes. These genes exhibited 6-18 nucleotide differences in RNA sequence between the pp genotype and PP/Pp genotypes, potentially resulting in an altered protein product with 2-6 amino acid differences between type 1 and type 2 genotypes. This study provides evidence for the prevalence of alternative RNA splicing in the transcription regulation of pecan dichogamy.
Speakers
avatar for Xinwang Wang

Xinwang Wang

Plant Geneticist, USDA ARS
Co-authors
JR

Jennifer Randall

New Mexico State University
NA
JS

Joe Song

New Mexico State University
NA
WC

Warren Chatwin

USDA ARS Southern Plains Agricultural Research Center
NA
YL

Yiyi Li

New Mexico State University
NA
Friday September 27, 2024 10:30am - 10:45am HST
Coral 1

10:30am HST

ORGH 3 - Optimizing the Application of Anaerobic Soil Disinfestation in Organic High Tunnel Vegetable Production Systems
Friday September 27, 2024 10:30am - 10:45am HST
The growth of the U.S. organic vegetable industry is currently limited by the availability of viable and effective solutions for the management of soilborne pests and pathogens. Anaerobic soil disinfestation (ASD) is a pre-planting biological method proposed for the management of a range of soilborne pests and pathogens affecting horticultural crops. As an organic amendment-based approach, ASD is implemented incorporating in the soil an easily degradable carbon (C) source, tarping the soil with plastic mulch, and irrigating the soil to field capacity. The selection of organic amendments suitable as C sources is critical for the efficacy of the treatment and its sustainability. Understanding how the physicochemical properties of alternative amendments may affect the efficacy of the ASD treatment, the soil fertility during and post ASD, and consequently the crop performance is critical. Therefore, a study was conducted on organic-certified land at the Penn State High Tunnel Facility to compare wheat middlings (WM), molasses (M), and soybean meal (SM) and their combination as C sources. Treatments tested included WM, M, SM, WM SM, and M SM applied at the standard rate of 6 Mg/ha of total C, SM0.5 applied to reach the equivalent of 3 Mg/ha of total C, and the untreated controls with (UTC W) and without (UTC) initial irrigation. Three weeks after the ASD treatment, Romaine lettuce was planted as a test crop. Organic amendments tested as C source were characterized by different C:N ratio, ranging between 6.3 (SM) and 57.2 (M). All the amendments tested ensured the achievement of good soil anaerobicity levels. The C:N ratio of the amendments significantly influenced the availability of nitrate-N during and post-ASD, thereby influencing the lettuce crop yield and quality performance. Having the highest C:N ratio, M applied by itself decreased the availability of nitrate-N during and post-ASD. Instead, SM characterized by the lowest C:N ratio, increased the availability of nitrate-N. The availability of N during the growing cycle, determined by the characteristics of the organic amendment and by the ASD treatment influenced the crop yield and nutritional profile. The results of the present study provide new insight for the selection of alternative C sources and the optimization of the ASD treatment in organic protected culture systems.
Speakers
FD

Francesco Di Gioia

Pennsylvania State University
Co-authors
BM

Ben Morrison

Pennsylvania State University
NA
ER

Erin Rosskopf

USDA Agricultural Research Service
NA
FD

Francisco Dini Andreote

Pennsylvania State University
NA
JK

Jason Kaye

Pennsylvania State University
NA
JO

Joe Ono Raphel

Pennsylvania State University
NA
KA

Kathleen Arrington

Pennsylvania State University
NA
RC

Radhika Chalam

Pennsylvania State University
NA
Friday September 27, 2024 10:30am - 10:45am HST
South Pacific 3

10:30am HST

TROP - Growing papaya in Mississippi
Friday September 27, 2024 10:30am - 10:45am HST
Papaya (Carica papaya) is an herbaceous perennial plant native to the tropical Americas. It thrives in tropical and subtropical climates. While the United States is the world’s largest papaya importer, it also cultivates a modest number of papayas, primarily in Hawaii, California, Texas, and Florida. The subtropical climate in Mississippi offers favorable conditions for papaya cultivation. However, frosts in late fall or early spring could pose threats to both plants and fruits. Appropriate cultivar selection and management strategies are critical for successful papaya production in MS. Currently, limited information is available on growing papayas in MS. The objective of this study was to investigate the potential of growing papaya as an alternative crop for specialty crop growers in MS. Preliminary data suggest that papaya plants can grow well in Mississippi. Different cultivars exhibited variations in plant size and vigor. Plants produced papaya fruits with variations in fruit number, size, and shape, as well as timing to fruiting among different cultivars. However, the relatively shorter growing season in MS compared to tropical climates resulted in insufficient time for most fruits to ripen before the onset of frost in late fall. Further research will involve evaluating additional cultivars, adjusting production schedules, employing season extension techniques, and assessing economic feasibility.
Speakers
GB

Guihong Bi

Mississippi State University
Co-authors
JL

Jacob Land

Mississippi State University
NA
TB

Taylor Blaise

Mississippi State University
NA
TL

Tongyin Li

Mississippi State University
NA
Friday September 27, 2024 10:30am - 10:45am HST
Lehua Suite

10:30am HST

VCM 6 - Optimizing nitrogen fertilizer concentrations in vegetable transplant production
Friday September 27, 2024 10:30am - 10:45am HST
Vegetable transplant producers supply approximately $250 million worth of transplants to vegetable growers throughout the United States. Proper nutrient application for transplant production is important for crop establishment and minimizing excessive fertilizer waste which can negatively affect surface and groundwater. However, nutrient application guidelines for vegetable transplants grown in soilless substrate are limited. Therefore, researchers undertook a study to determine optimal nitrogen (N) concentrations for the top five transplanted vegetable crops produced in California. Greenhouse trials were conducted on leaf lettuce, romaine lettuce, processing tomato, broccoli, and celery transplants. Three treatments were applied in each trial (One 200-cell plug tray per treatment, replicated five times each): (1) 400 ppm N; (2) 200 ppm N; (3) 50 ppm N. Fertigation was applied to trays placed on weighing-lysimeters and total daily transpiration was recorded. Once transplants were fully developed, they were harvested and analyzed for shoot fresh weight and shoot dry weight. Fresh plant tissue was sent to an agricultural laboratory for nutrient content testing. Total nutrient uptake (mg) was calculated by multiplying nutrient tissue content (%) by shoot dry weight (mg). N fertilizer concentration (mg*L-1) was calculated by dividing the total N uptake value (mg) by transpiration (L). Transplants in the 400 ppm treatment had significantly higher N tissue content, compared to the 200 and 50 ppm treatments, in all crop trials except for leaf lettuce. In the leaf lettuce trial, the 400 and 200 ppm treatments had similar N tissue content. Average shoot dry weight was similar between the 200 and 400 ppm N treatments in all five crops, indicating that both treatments provided sufficient N. Based off these results, we recommend applying 246 ppm N to leaf lettuce, 232 ppm N to romaine lettuce, 304 ppm N to processing tomato, 437 ppm N to broccoli, and 262 ppm N to celery transplants. These values are based off the calculated N fertilizer concentrations which produced the highest shoot dry weights.
Speakers
EV

Emma Volk

UC Cooperative Extension
Co-authors
BP

Bruno Pitton

University of California Cooperative Extension
NA
LO

Lorence Oki

University of California, Davis
NA
Friday September 27, 2024 10:30am - 10:45am HST
South Pacific 2

10:30am HST

VSF 5 - Prohexadione Calcium is an Effective, Dose Dependent Growth Retardant of ‘Osage’ Blackberry
Friday September 27, 2024 10:30am - 10:45am HST
Blackberry primocane growth management in the Southeastern US relies on tipping to manage vegetative growth. Tipping can increase lateral branching, bearing surface, and subsequent yield. However, the practice is labor intensive and expensive (~$600/acre). Furthermore, tipping wounds are sites for cane blight infection (Leptosphaeria coniothyrium) resulting in cane dieback, decline and death. Alternative strategies to tipping could reduce labor and fungicide inputs in a given season. Prohexadione calcium (P-Ca) is commonly used to control terminal shoot growth in other Rosaceous crops. We evaluated the relationship between P-Ca rate on blackberry vegetative and reproductive development. The experiment was conducted on a mature planting of ‘Osage’ floricane-fruiting blackberry at Clemson University’s Musser Fruit Research Center in Seneca, SC. The experiment had a completely randomized design with four replications. Treatments consisted of an untreated control and P-Ca applied at 62.5, 125, 250, and 500 ppm with a 0.125% (v:v) non-ionic surfactant and 0.39% (v:v) water conditioner. P-Ca treatments were applied 6 times at ~21 day intervals to the same plots across two consecutive years, 2019 and 2020. Regression analysis was conducted to determine the relationships between P-Ca and measured parameters. There was a consistent, negative relationship between P-Ca rate and primocane height across two years, which was linear in 2019 and curvilinear in 2020. A negative curvilinear relationship between P-Ca rate and yield was observed in 2020 beginning 8 weeks after P-Ca treatments were initiated until the final harvest. There were no consistent effects of P-Ca on fruit weight. P-Ca reduced total lateral length, number of lateral branches, and final cane length by 60 - 65% at the 250 ppm and 500 ppm rates. P-Ca is an effective growth retardant of blackberry, but the negative relationship between P-Ca rate and yield merits additional research. Future research should focus on post-harvest applications of P-Ca to minimize dormant pruning costs and applications in controlled environments.
Speakers Co-authors
JC

Juan Carlos Melgar

Clemson University
NA
TM

Thomas M. Kon

North Carolina State University
NA
Friday September 27, 2024 10:30am - 10:45am HST
Coral 3

10:30am HST

WCPM 4 - Directed Energy System: A Non-chemical Approach for the Management of Nematodes, Pathogens, and Weeds in Nurseries
Friday September 27, 2024 10:30am - 10:45am HST
Oregon leads the United States in the production of several ornamental nursery products including shade trees, conifers, and flowering trees. Soilborne pathogens and weeds are major constraints to the production of tree seedlings for the ornamental industry. Failure to control pathogens can result in seedling death or unintentional distribution of infected nursery stock while failure to control weeds can lead to competition with seedlings for water and nutrients. One of the primary ways to control soilborne pathogens and weeds is through pre-plant fumigation with methyl bromide. The use of this chemical is detrimental to the environment and human health, making it urgent to develop safer alternatives. Our long-term goal is to discover new ways to manage nematodes, soilborne pathogens, and weeds that will reduce reliance on pesticides and soil fumigants and be safer for the environment. Directed Energy System (DES) has been developed as a novel application technique, which generates pulses of electricity capable of killing nematodes, pathogens, and weeds. Controlled experiments were conducted against Meloidogyne chitwoodi, Phytophthora cinnamomi, and Cyperus esculentus to determine the electrical parameters required to kill each organism. Preliminary data demonstrated that the energy required to kill 90% of M. chitwoodi eggs was 23.4 J/cm3 of soil and for C. esculentus nutlets the energy for reduce weed growth by 50% ranged from 55 to 116 J/cm3 of soil.
Speakers
TB

Tatiana Benedetti

Oregon State University
Co-authors
JC

Jason Crisp

Lisi Global
NA
MM

Marcelo Moretti

Oregon State University
Friday September 27, 2024 10:30am - 10:45am HST
South Pacific 4

10:45am HST

CE 7 - The Nitrate to Ammonium Ratio Impacts Strawberry Runnering and Daughter Plant Number
Friday September 27, 2024 10:45am - 11:00am HST
The use of controlled environments to produce disease-free vegetative clones of strawberry (Fragaria ×ananassa) is increasing. However, protocols for mother plant management that optimize runner and daughter plant number need to be developed. Studies have shown that decreasing the fraction of nitrogen (N) supplied as nitrate (NO3-) can encourage vegetative growth in other crops. Our objective was to identify the %NO3--N that maximized runner and daughter plant number. Strawberry ‘Albion’, ‘Fronteras’, and ‘Monterey’ were grown in 19.1-cm pots filled with a peat-based substrate. Plants were irrigated with a modified strawberry nutrient solution (Yamazaki) that provided a total of 100 mg·L-1 N. The percent of total N supplied as NO3- ranged from 0% to 100%, with the remainder supplied as ammonium (NH4 ). Runners and daughter plants were harvested after eight and 16 weeks of treatment. The impact of %NO3- on cumulative runner number was cultivar specific. ‘Albion’ was not impacted, and the overall mean was 9 ± 1 (± SE).‘Fronteras’ exhibited a quadratic response. It increased from 10 ± 2 at 0% NO3- to 17 ± 2 at 60% NO3-; the calculated maximum runner number was with 64% NO3-. ‘Monterey’ exhibited a linear increase, from 14 ± 1 at 0% NO3- to 22 ± 1 at 100% NO3-. The impact of %NO3- on cumulative daughter plant number was also cultivar specific. ‘Abion’ exhibited a linear increase, from 28 ± 2 at 0% NO3- to 37 ± 10 at 100% NO3- . ‘Fronteras’ exhibited a quadratic response and increased from 19 ± 2 at 0% NO3- to 45 ± 7 at 60% NO3-. ‘Monterey’ also exhibited a quadratic response and increased from 49 ± 4 at 0% NO3- to 90 ± 7 at 80% NO3-. Calculated maximum daughter plant number occurred at 66% and 81% NO3- in ‘Fronteras’ and ‘Monterey’, respectively. Overall, at least 60% NO3- provided robust runner and daughter plant number, but the response depended on cultivar evaluated. ‘Monterey’ and ‘Albion’ appear to prefer a higher %NO3- than ‘Fronteras’ for maximum runner and daughter plant number.
Speakers
EY

Erin Yafuso

United States Department of Agriculture
Co-authors
JB

Jennifer Boldt

United States Department of Agriculture
Friday September 27, 2024 10:45am - 11:00am HST
Nautilus 1

10:45am HST

CHMG 2 - Utilizing Facebook and Instagram to Distribute a Residential Horticultural Needs Assessment
Friday September 27, 2024 10:45am - 11:00am HST
Homeowners and gardeners source their landscape education from various media outlets and social media platforms. Leveraging the substantial following of the UF/IFAS Master Gardener social media page, which boasts over 40,000 followers, presents a unique opportunity to discern the horticultural education needs of homeowners and their preferred dissemination methods. In 2023, a Qualtrics horticultural needs assessment survey was developed and distributed via Facebook and Instagram to followers. Prior to survey distribution, an Institutional Review Board was completed and approved under the non-human/exempt auto-determination tool. The Qualtrics needs assessment comprised twelve questions covering topics such as horticultural interests, availability, and preferred learning platforms. Four visually engaging posts were shared, two each in December 2023 and January 2024. Of these posts, 309 respondents agreed to participate in the study. Our findings aligned with current gardening trends, with homeowners expressing a need for information on native plants, pollinators, vegetable gardening, and invasives. Among respondents, 21% favored online classes over 15% for in-person classes. Additionally, digital documents were preferred by 18% of respondents compared to 14% for print documents. Notably, 20% of respondents expressed a preference for short online videos for receiving horticultural information. Survey participants were also queried on their preferred time of year for attending classes, both in person and online, with no clear preference observed. Regarding in-person classes at local extension offices, 54% indicated willingness to attend, while 11% were unaware of their local extension office's location. When asked about their interactions with Master Gardener Volunteers, 31% reported satisfaction, 12% dissatisfaction, and 48% had not interacted with a Florida Master Gardener Volunteer. Interestingly, 62% of respondents expressed a preference for garden-related content on YouTube. While the response rate was relatively low, it suggests that direct email or in-person approaches might have yielded more productive results. Nonetheless, the findings are compelling, indicating a promising direction for extension programming in the digital age. They underscore the potential benefits of transitioning towards short-form video content and utilizing platforms like YouTube to effectively meet homeowners' horticultural education needs. Overall, the study illuminates the evolving landscape of horticultural education and underscores the importance of adapting dissemination strategies to better engage homeowners in the digital realm.
Speakers
CJ

Claude Judith Jean

University of Florida
Friday September 27, 2024 10:45am - 11:00am HST
South Pacific 1

10:45am HST

FLOR 3 - Moisture Content Effects Microbial Activity in Substrates Derived from Five Different Hammermilled Wood Species Over the Course of Greenhouse Petunia Production
Friday September 27, 2024 10:45am - 11:00am HST
Recently, the limited availability of Sphagnum peat moss due to poor weather conditions impacting harvests, and additional scrutiny from media and public outlooks has brought up serious questions about the long-term security of peat use in the horticulture industry. The search for alternative amendments began decades ago, with several products being evaluated over the years. Many have been found suitable for niche production settings, with few seeming to fit the industry somewhat ubiquitously. Of these, wood fiber is seemingly the most promising as it is a renewable resource that is available globally. Wood fiber amendments have been trialed extensively with industry emerging and scaling internationally. Wood can be processed to support many different applications in horticulture, giving it more robust qualities than other top components. There are some disadvantages to wood usage, namely, nitrogen immobilization. Wood contains large amounts of easily degradable carbon. Therefore, microorganisms will consume this carbon for energy by utilizing plant available nitrogen causing plant nutrient deficiencies. Microbial community activity is heavily influenced by moisture. Considering this, a study was developed to observe how the microbial activity of different hammermilled wood tree species may be influenced by moisture content in a greenhouse crop production cycle. Five tree species (Abies concolor, Calocedrus decurrens, Pinus lambertiana, Pinus ponderosa, and Pseudotsuga menziesii) were harvested in California and hammermilled. The wood particles were blended with a commercial peat-based substrate at 30% (by vol.). Supertunia ‘Honey’ plugs were planted in each of the substrate blends and grown on a greenhouse bench for 75 days. The crops were held at 25% and 35% volumetric water content using cantilever-style lysimeters and fertigated with water-soluble fertilizer, weekly. Crop growth and performance was assessed throughout production. Substrate CO2 was assessed pre- and post- production to assess microbial activity. The results will help assess the potential of utilizing differing tree species for wood fiber, and understand any adjustments that will be necessary to production practices.
Speakers
AM

Amanda Mizell

Louisiana State University AgCenter
Co-authors
BJ

Brian Jackson

North Carolina State University
NA
DA

Damon Abdi

Louisiana State University Agricultural Center
JF

Jeb Fields

LSU AgCenter Hammond Research Station
Friday September 27, 2024 10:45am - 11:00am HST
Kahili

10:45am HST

GG 3 - Alaska Can Grow More Than Giant Vegetables: The Potential of Rhubarb for Specialty Crop Producers
Friday September 27, 2024 10:45am - 11:00am HST
Specialty crop producers in Alaska need consistent, suitable crop and varietal options for successful commercial production, as food security is a major concern in this state that imports 95% of its food. The climate in much of Alaska is ideal for cool season, perennial corps that are winter hardy, such as Rhubarb (Rheum sp.). Rhubarb was brought to Alaska through several waves of immigration from regions extending from Russia through England and is now established throughout the state. Once a site for the National Plant Germplasm System (NPGS) Arctic and Subarctic Plant Gene Bank, the University of Alaska Fairbanks Matanuska Experiment Farm and Extension Center still maintains a collection of 41 accessions of Rheum sp. in the field. In addition, a new collection of heirloom rhubarb plants has been assembled by a local grower and maintained in large pots. In this project, we collected leaf samples from the heirloom collection plants for genotyping and phenotyping, as well as benchmark samples from plants remaining in the former germplasm collection, to provide an understanding of relatedness and desirable characteristics. A 5 cm square sample of leaf tissue was harvest from each plant, dried, and sent to a commercial laboratory for genotyping. Size and color of leaves and petioles, dates of emergence, plant vigor, and juice quality were measured on plants from the heirloom collection. Finally, surveys carried out of the last 12 years targeted a diversity of stakeholders (commercial producers, business owners, and the general public) to identify rhubarb quality expectations, including flavor, juice content, petiole color, and plant vigor. Based on genotyping results, plants not genetically redundant to those in the NPGS rhubarb collection currently located in Pullman, Washington, will be added to the collection. We present recommendations for variety suitability for different climate regions of Alaska based on the traits measured, taking into account varieties of rhubarb currently available wholesale to Alaska. Recommendations are also presented for further research into commercial production and added-value characteristics.
Speakers
CM

Carol Miles

Washington State University
Co-authors
AC

Alex Cornwall

USDA ARS
NA
AK

Ann Kowenstrot

University of Alaska Fairbanks
Friday September 27, 2024 10:45am - 11:00am HST
Coral 1

10:45am HST

ORGH 3 - Cover Crops Potential for Regulating Soil Moisture and Temperature in Drive-row of an Irrigated Organic Vineyard
Friday September 27, 2024 10:45am - 11:00am HST
The utilization of cover crops in vineyards has been promoted for their role in moderating soil climate, thus enhancing vineyard resilience to extreme weather conditions. This study evaluated the effectiveness of three drive-row cover crop treatments in regulating soil moisture and temperature within an irrigated organic vineyard characterized by loamy sand soil, located in the semiarid Okanagan Valley, Canada, over the period from 2021 to 2023. Selection of cover crop species was informed by prior greenhouse and field screening experiments. The implemented treatments, established in May 2021, included a mixture of perennial ryegrass, tillage radish, and white clover (PRTRWC); a fescue mixture with white clover (FWC); cereal rye with hairy vetch (CRHV); and a Control (existing vegetation/weeds). The vineyard was equipped with drip lines and undercanopy sprinklers. Soil moisture and temperature were monitored every four hours using Teros 11 sensors at a 10 cm depth in the drive-row. Seasonal observations revealed the highest soil volumetric water content (Ɵv) from November to April, aligning with cooler temperatures and increased precipitation. The Ɵv ranged from 0.10 to 0.14 and significant differences in average Ɵv were noted among the all treatments over the three growing seasons (May to Oct), with CRHV displaying the highest levels, followed by FWC, Control, and PRTRWC. Notably, substantial differences in Ɵv (
Speakers
MS

Mehdi Sharifi

Summerland Research and Development Centre
Dr. Mehdi Sharifi is a “soil nutrient management” research scientist at Summerland Research and Development Centre in British Columbia, Canada. Before his current position, he was a professors at Trent and Dalhousie Universities. He completed two postdoctoral fellow positions... Read More →
Co-authors
JY

Jamie Yearley

University of British Columbia Okanagan Campus
NA
MJ

Melanie Jones

University of British Columbia Okanagan Campus
NA
ZZ

Zahra Zolfaghari

University of British Columbia Okanagan Campus
NA
Friday September 27, 2024 10:45am - 11:00am HST
South Pacific 3

10:45am HST

VCM 6 - Growing Resilient Broccolini: Harnessing Clover Living Mulch for Weed Suppression and Yield Enhancement
Friday September 27, 2024 10:45am - 11:00am HST
Growing broccoli to a marketable standard can be difficult in a changing climate with more extreme heat events during the growing season. The use of more heat tolerant Brassica species in combination with living mulch could address both issues. A study in Brookings, SD investigated established clover living mulch and in-row soil management impacts on the performance of four of broccolini (Brassica oleracea) cultivars – ‘Melody,’ ‘BC1611,’ ‘Burgundy,’ and ‘Bonarda.’ Three established clover varieties (‘Domino’ white clover (Trifolium repens), ‘Aberlasting’ white x kura clover (T. repens x ambiguum), and ‘Dynamite’ red clover (Trifolium pratense)) and a bare-ground control were used in combination with four in-row soil management strategies (till, no-till, till fabric, and no-till fabric). These 16 combinations were evaluated for their impact on weed suppression, broccolini crop growth and yield. It was observed that annual weeds such as yellow foxtail (Setaria pumila) and Venice mallow (Hibiscus trionum) were present in bare ground plots and were reduced in all clover plots. Some perennial weeds such as dandelion (Taraxacum spp.) and perennial sow thistle (Sonchus arvensis) were able to compete with clover. Sufficient clover biomass was accumulated for weed suppression. Weed biomass was reduced by 80% in white and red clover plots, and 95% in the white x kura clover plots compared to the control. Broccolini yield was reduced within all three clover no-till treatments. Broccolini grown in other clover soil management combination had similar yields indicating greater resistance to yield decreases commonly observed in living mulch research. Other data collected in this study included clover nodule counts and broccolini crop health metrics – height, canopy width, and SPAD. Results from the first year of research demonstrate that perennial clover living mulch can be used in the Great Plains to suppress weeds between planting rows. However, the use of landscape fabric within the planting row is necessary to prevent a reduction in broccolini yield. Planting broccolini into a living mulch system shows potential for vegetable producers to reduce inputs and labor on their farms while maintaining crop yield.
Speakers
CR

Connor Ruen

South Dakota State University
NA
Co-authors
KL

Kristine Lang

South Dakota State University
TN

Thandiwe Nleya

South Dakota State University
NA
Friday September 27, 2024 10:45am - 11:00am HST
South Pacific 2

10:45am HST

VSF 5 - Impacts of the ‘Fan’ Training Method on Blackberry Yield and Fruit Quality on the Rotating Cross-Arm Trellis
Friday September 27, 2024 10:45am - 11:00am HST
Based on six years of research at the University of Arkansas, the rotating cross-arm (RCA) trellis has been shown to improve several aspects of blackberry production such as yield and fruit quality. Through this research, a new training method coined the ‘fan’ method was developed with the potential to maximize canopy fill and decrease labor. A trial was conducted from 2022 to 2024 at the University of Arkansas Fruit Research Station (UAFRS) in Clarksville, AR to verify the ‘fan’ method and test new cultivars not used in previous trials. The blackberry cultivars ‘Ponca’, ‘Von’ and ‘Caddo’ were planted in 2021 on a 33m row of t-trellis and a 33m row of RCA trellis in a randomized complete block arrangement. The plants were spaced 0.76 m apart in four plant plots replicated three times per trellis treatment. The ‘fan’ training method (primocanes tipped at 30 cm and laterals trained upward and fanned out on the long arm) was implemented on the RCA trellis treatment for all plants. The t-trellis was tipped at the top wire following practices standard for the region. Blackberry yield, fruit quality, and physiological data were collected during 2023 and 2024. Preliminary results from 2023 showed the ‘fan’ method on the RCA can achieve similar yields to the T-trellis but offer the opportunity to protect the crop from severe cold events and reduce the incidence of fruit quality disorders for some cultivars. All the varieties evaluated were found to be suitable for use on the RCA with the fan method however differences in cane vigor were noted and cultivar can be the biggest determinant of yield and fruit quality regardless of trellis type.
Speakers
avatar for Lizzy Herrera

Lizzy Herrera

University of Arkansas System Division of Agriculture
Co-authors
AL

Amanda Lay Walters

University of Arkansas System Division of Agriculture
NA
AM

Amanda McWhirt

University of Arkansas System Division of Agriculture
KB

Keilah Barney

University of Arkansas System Division of Agriculture
NA
MD

Mataya Duncan

University of Arkansas System Division of Agriculture
NA
RT

Renee Threlfall

University of Arkansas System Division of Agriculture
NA
Friday September 27, 2024 10:45am - 11:00am HST
Coral 3

10:45am HST

WCPM 4 - Sweetpotato-associated Virome in Mississippi
Friday September 27, 2024 10:45am - 11:00am HST
Sweetpotato (Ipomoea batatas; Convolvulaceae) is an economically important specialty crop with an overall U.S. production valued at more than $720 million (2020 data, USDA-NASS). Even though virus infections are a major constraint to the sweetpotato industry across the United States and around the globe, organized studies have not been conducted to understand virus diversity and incidence. Therefore, an objective of a transdisciplinary multistate, Specialty Crop Research Initiative (SCRI), CleanSEED Project is to characterize viruses associated with sweetpotato production in major producing states. To that aim, 25 different locations/production fields in Mississippi were surveyed during the 2023 production season to collect symptomatic foliar tissue for total RNA extraction. The detection and identification of viruses of sweetpotatoes was based on a high-throughput sequencing approach on an Illumina platform utilizing 2x150 nt pair-end methodology, followed by computational analyses of billions of raw sequence reads. The four potyviruses, considered of major economic importance for the crop, were prevalent in the state and frequently occurred in mix infections. Furthermore, a few other viruses with possible hosts different than plant, were associated with plants analyzed in this study. This research was supported by the intramural research program of the U.S. Department of Agriculture, National Institute of Food and Agriculture, Specialty Crop Research Initiative, accession no. 1029242.
Speakers
SS

Sead Sabanadzovic

Mississippi State University
Co-authors
LH

Lorin Harvey

Mississippi State University
NA
MS

Mark Shankle

Mississippi State University
NA
NA

Nina Aboughanem

Mississippi State University
NA
Friday September 27, 2024 10:45am - 11:00am HST
South Pacific 4

10:59am HST

Tropical Horticultural Crops (TROP)
Friday September 27, 2024 10:59am - 11:50am HST
Comparing The Effect Of Potyviruses On The Yield Of Different Generations Of Beauregard Sweetpotato Variety - Sathish Ponniah
“Midnite” and “Festival”: Combining Caribbean and African Hibiscus sabdariffa - Thomas Zimmerman
Metabolomic Survey of Puffy Skin Date Fruit - Yoko Hiraoka
Identifying the formation of aroma compounds in mango using a multi-omics approach - Yu Wang
Establishment of Avocado trees in the United States Virgin Islands - Samuel Joseph
Friday September 27, 2024 10:59am - 11:50am HST
Lehua Suite

11:00am HST

TROP - Comparing The Effect Of Potyviruses On The Yield Of Different Generations Of Beauregard Sweetpotato Variety
Friday September 27, 2024 11:00am - 11:10am HST
Sweetpotatoes (Ipomoea batatas) have become increasingly popular over the last two decades. It is higher in beta-carotene than many other vegetables and a source of potassium, fiber, and vitamins A and C. Orange-fleshed varieties have a significant role in addressing vitamin A deficiencies, especially in pregnant women and children in developing countries. Sweetpotatoes are vegetatively propagated and susceptible to viruses that accumulate with each planting cycle (generation), leading to cultivar decline. This can affect the yield and quality of the sweetpotato roots. Over 30 viruses have been identified in sweetpotato. In U.S. commercial production fields, four potyviruses such as Sweetpotato feathery mottle virus (SPFMV), Sweetpotato virus G (SPVG), Sweetpotato virus 2 (SPV2), and Sweetpotato virus C (SPVC) are often commonly found. Potyviruses are aphid transmitted in a non-persistent manner. The potyvirus, Sweetpotato feathery mottle virus (SPFMV), is, by far, the most common sweetpotato virus. The objectives of the study are to compare the level of virus infection in five different generations (G1, G2, G3, G4, G6) with the yield performance in the Beauregard variety under field conditions. The different generation roots were collected from the previous experiments, and slips were multiplied under greenhouse conditions of the University of Arkansas at Pine Bluff (UAPB) farm. The slips were planted 12 inches apart with a 30-inch row spacing in four replications using a randomized block design during the summer of 2023. The roots were collected and cured to measure the various yield parameters like total marketable yield, U.S. No. 1, Jumbos Canners, and Culls. The random roots were selected to quantify the viral infections across the five generations using multiplex Reverse Transcription-Polymerase Chain Reaction (mRT-PCR). We observed significant differences in the U.S. No. 1 roots and Canners across the generations. In total marketable yield, 42.5% reduction was observed between the younger generation (G1, G2) and the older (G6) generation. Here, SPFMV was found to be dominant across the generations. Overall, a higher rate of virus infections was detected in the older generation (G6) than in younger generations (G1, G2).
Speakers
Friday September 27, 2024 11:00am - 11:10am HST
Lehua Suite

11:00am HST

CE 7 - Effect of Monosilicic Acid on Growth and Physiology of Lettuce
Friday September 27, 2024 11:00am - 11:15am HST
Due to the high operation costs of indoor crop production, improving resource use efficiency to reduce costs has gained importance for sustainability in recent years. Silicon (Si) is not an essential plant nutrient since it is not a component of any structural or metabolic molecule, and plants do not suffer from Si deficiency. However, Si applications have shown beneficial effects on various crops, including improved growth, quality, stress tolerance, and water use efficiency (WUE). This study evaluated the effects of Si on indoor lettuce production to enhance lettuce growth and WUE. Two-week-old lettuce seedlings (Lactuca sativa cv. ‘Green Forest’ and ‘Rouxai’) were transplanted into 5-L deep water culture systems and grown for four weeks in a custom growth chamber with an average temperature/relative humidity of 22.4°C/58.8% and light intensity of 230 µmol/m²/s PPFD. The nutrient solution was weighed and replenished weekly. Si (DUNE™ stabilized monosilicic acid) was applied weekly to plants following two application methods (RA=root application and FS=foliar spray) and three concentrations (Control=0 ppm, C1=264 ppm, and C2=528 ppm). RA C1 significantly improved the shoot fresh weights (FW) and dry weights (DW) of both lettuce cultivars, while FS C1 was less effective than RA. Root growth showed the opposite trend, with FS C1 having the highest root FW and DW of both cultivars. However, root morphology showed cultivar-specific responses, with RA C1 producing the highest root length and surface area in ‘Green Forest’ and FS C1 the highest root surface area and volume in ‘Rouxai.’ WUE was significantly improved by RA C1, RA C2, and FS C2 in ‘Green Forest’ and RA C1 in ‘Rouxai’ compared to the control. Taken together, root application of Si at C1-264 ppm concentration most effectively improved the indoor lettuce growth and WUE.
Speakers
SC

Seunghyun Choi

Postdoctoral research associate, Texas A&M Agrilife Research
Co-authors
JH

Joshua Harvey

Texas A
NA
VJ

Vijay Joshi

Texas A
NA
Friday September 27, 2024 11:00am - 11:15am HST
Nautilus 1

11:00am HST

CHMG 2 - Exploring the Ethical Viewpoints of Proplifiting Among Consumers
Friday September 27, 2024 11:00am - 11:15am HST
In recent years, the trend of owning and propagating houseplants has steadily grown. Consumers find this hobby to be relaxing and find it rewarding when their cuttings successfully grow roots and new leaves. Because of the ease that propagation gives us to clone plants, many people are exploring methods to acquire more plants for free. One common method is through proplifting. Proplifting is the habit of stealing plant material for the practice of creating new plants; this is done through collecting discarded material (leaves, nodes, roots, seed), or by stealing parts of a plant that are still attached. While proplifting appears harmless, it is important to consider all factors, such as how it might affect the business, non-profit, or individual that one is taking this plant material from. Additionally, taking protected plant material – such as from plants that are being grown from conservation efforts – could drastically harm the preservation of a species. This national survey looks at how consumers view the ethics around proplifting and the degree to which they would consider a situation to be ethically acceptable or unacceptable.
Speakers
LG

Leandria Garrett

University of Georgia
Co-authors
JC

Julie Campbell

University of Georgia
Friday September 27, 2024 11:00am - 11:15am HST
South Pacific 1

11:00am HST

FLOR 3 - Stratification significantly reduces the phytotoxic effects of fresh hardwood
Friday September 27, 2024 11:00am - 11:15am HST
With a global increased demand for growing substrates and specifically wood alternative substrates, methods are being tested to better understand wood as a product and how to incorporate wood into growing medium substrates. This study investigated the use of fresh whole-tree loblolly pine and whole-tree hardwood in horticultural greenhouse settings, focusing on how varying wood blend compositions and levels of stratification affect plant growth. Analysis revealed that increasing hardwood percentage in blends led to decreased plant growth, while stratification reduced differences among blends. Notably, at lower stratification levels, plant growth resembled that of the control treatment. Statistical tests confirmed these trends, highlighting the significant impact of wood blend composition on plant dry weight. Findings suggest that while hardwood incorporation decreases growth, stratification can mitigate differences among blends, allowing for the incorporation of untreated wood material. These results offer insights for optimizing wood blend usage in greenhouse cultivation, providing sustainable solutions for horticultural practices. Key Words: Hardwood, Stratification, Phytotoxicity, Wood Blends, Plant Growth.
Speakers
AT

Andre Truter

North Carolina State University
Friday September 27, 2024 11:00am - 11:15am HST
Kahili

11:00am HST

GG 3 - Utilization of Germplasm to Improve Illinois Horseradish
Friday September 27, 2024 11:00am - 11:15am HST
Horseradish (Armoracia rusticana, Brassicaceae) is an important specialty crop in Illinois, with most commercial production adjacent to St. Louis, Missouri in what is known as the Mississippi Bottoms. The continued development of new, improved horseradish cultivars is critical to sustain this important specialty crop industry, since horseradish clonal cultivars tend to "run out" and lose their productivity over a period of about 10 years. A small germplasm collection of clones from eastern Europe and Russia, as well as old cultivars no longer in wide use and other breeding materials that were saved from the breeding program has been maintained since the 1960s, first at University of Illinois until the early 2000s and now at Southern Illinois University-Carbondale. During the last 20 years, germplasm has been utilized from various sources to improve horseradish so this industry can sustain itself for the near future. The following examples are provided to illustrate the importance of new germplasm in new horseradish cultivar development. Accession 761A collected from Drążgów, Poland was instrumental in developing horseradish cultivars with tolerance to internal root discoloration which is caused by a soil-borne pathogen complex. The germplasm clone Czech has been very effective in transmitting its large root size trait to its resulting progeny and was used in many crosses made from 2005 to 2010. Many cultivars grown today have this germplasm source in their background. Another important clonal cultivar known as 9705 was widely grown during the 2000s and resulted from outcrossing accession 758A collected from Ribnica, Slovenia with an unknown male. Additionally, 315 is another very important cultivar that was the workhorse for the industry from 2005 to 2015 having lineage also from 758A. 15K was another industry workhorse in the late 1990s to early 2000s, and had its primary lineage traceable to 856A, an accession from the Czech Republic. These are a few examples of how germplasm sources have contributed to sustaining the Illinois horseradish industry and each will be discussed in further detail regarding their specific benefits. Moreover, most are still used in some capacity in the breeding program today.
Speakers
AW

Alan Walters

Southern Illinois University
Friday September 27, 2024 11:00am - 11:15am HST
Coral 1

11:00am HST

ORGH 3 - Apple Rootstocks Affect Soil Rhizosphere Microbial Communities and Root Exudate Composition
Friday September 27, 2024 11:00am - 11:15am HST
The plant rhizosphere plays a key role in plant function and immunity. Apple Replant Disease (ARD) is a dysbiosis in apple rhizosphere environments that have a history of apple cultivation. Due to increased intensification of apple growing systems and land scarcity, ARD incidence is on the rise and can result in a 50% loss of profitability to growers. Soil fumigation is a common practice for mitigating ARD, but has limited efficacy and is not allowed in some areas because of potential for environmental damage and human harm. Using resistant rootstocks is a key strategy in overcoming ARD. To understand rootstock resistance, it is important to describe and characterize the microbial communities of various rootstocks in an environment conducive to microbial health. We planted an organically managed apple orchard with 5 randomized repetitions of 15 different rootstocks. In both 2022 and 2023, we sampled the soil adhering to the roots of these trees for DNA extraction in order to characterize both bacterial and fungal microorganisms in the rhizosphere of the rootstocks in our research. We also established an aeroponic greenhouse trial (randomized with three repetitions) to sample rhizodeposits from 6 of the rootstocks used in the orchard trial, with the aim of characterizing metabolites with untargeted HPLC/LCMS. Bacterial phyla and genera differed in relative abundance between the rootstocks. A sparse PLS (partial least squares) discriminant analysis of rootstock exudates revealed differential sorting of some rootstocks. Neither study revealed clear biological indicators for ARD resistance, but the results evince that rootstock genotype does influence both microbial community and tree root exudation patterns.
Speakers
JC

Julie Cardon

Cornell University
Co-authors
GF

Gennaro Fazio

Cornell University /USDA
NA
GP

Greg Peck

Cornell University
NA
JT

Janice Thies

Cornell University
NA
TR

Terence Robinson

Cornell University
NA
Friday September 27, 2024 11:00am - 11:15am HST
South Pacific 3

11:00am HST

VCM 6 - Foliage Removal on Processing Sweet Corn Reduces Yield Most Strongly Near Tasseling
Friday September 27, 2024 11:00am - 11:15am HST
Sweet corn is an important processing crop in the upper Midwestern United States. It can be insured for hail losses, but actuarial tables are based on field corn. The first step in developing accurate yield loss estimates is to determine yield loss due to stand loss. The second step is to determine yield loss due to defoliation. To understand the impacts of defoliation on sweet corn yield, we compared ear yield with estimated 25, 50, 75, or 100% of leaf area removed at five times throughout the growing season to control plots that were not defoliated. Defoliation was carried out with a Christmas tree shearing knife or machete. We repeated this in three consecutive years at two locations, without irrigation or supplemental fertilizer. Yield was measured as both green ear mass and cut kernel mass. Measured loss due to defoliation was generally less than actuarial estimates, except shortly before tasseling or at 25% defoliation. A regression equation predicting yield relative to control based on a) growing degree days before damage and b) percent defoliation were developed, combining all site-years. We measured little yield loss with 25 or 50% defoliation or 75% defoliation near V8, and we measured greatest yield loss near tasseling with 100% leaf removal. Kernel and ear mass were strongly correlated. These results illustrate resilience of sweet corn to foliage loss and potential need for adjustment of actuarial tables for hail loss.
Speakers
avatar for Charlie Rohwer

Charlie Rohwer

Scientist, University of Minnesota
Co-authors
JL

Joe Lauer

University of Wisconsin-Madison
NA
MZ

Mark Zarnstorff

National Crop Insurance Services
NA
Friday September 27, 2024 11:00am - 11:15am HST
South Pacific 2

11:00am HST

VSF 5 - Evaluation of a Strawberry (Fragaria × ananassa) Cultivar Trial for Yield and Fruit Quality in Lubbock, Texas
Friday September 27, 2024 11:00am - 11:15am HST
Due to its sweet and aromatic flavor, nutritional value, and health-associated beneficial compounds, strawberry (Fragaria x ananassa) is worldwide cultivated fruit crop. Texas strawberry cultivation is gaining popularity because strawberry production may give considerable economic returns in a relative short period of time. However, profitable strawberry cultivation is intricately tied to selection of suitable cultivars for prevailing environmental conditions. To identify the most appropriate cultivars for a specific region, it is critical to thoroughly evaluate strawberry cultivar growth, yield potential, and various quality characteristics within each diverse agro-climatic location. Hence, to evaluate strawberry cultivars for superior yield and fruit quality characteristics and determine suitable cultivars for cultivation in the region, this study was conducted at the TAMU AgriLife Research and Extension Center in Lubbock, TX. Twenty cultivars (8 day neutral and 12 June bearing) were established Fall of 2022 as bare root plants and data collection began Spring of 2023. Each cultivar was assessed for morphological, physiological, and agronomic traits. Trial results reveal significant variation in performance of evaluated cultivars. Yield and berry number were greatest for ‘Rikas’, ‘Cabrillo’, ‘Brilliance’, ‘Fronteras’, and ‘Beauty’, whereas ‘Keepsake’ was the lowest yielding cultivar and produced the fewest number of fruits. Berry size was greatest for ‘Monterey’, ‘Sweet Ann’, ‘Royal Royce’, ‘Cabrillo’, ‘Valiant’ and ‘San Andreas’, whereas ‘Keepsake’ had the smallest berries. Leaf gas exchange measurements revealed photosynthetic rate and conductance was least for ‘Sierra’. Fruit quality (total soluble solids, °Brix) was greatest for ‘Keepsake’ (11.9°) and lowest for ‘Radiance’ (7.6°). ‘Keepsake’ and ‘Victor’ fruit appeared to be resistant to Botrytis, whereas ‘Festival’ and ‘San Andreas’ were more susceptible. ‘Victor’ plants had the greatest percentage canopy green cover, whereas ‘Medallion’ had the least green canopy cover. Yield and fruit quality data indicate top day-neutral cultivar were ‘Cabrillo’, ‘Rikas’, and ‘Beauty’, while top June-bearing cultivars were ‘Brilliance’ and ‘Fronteras’. Preliminary research suggests cultivars ‘Rikas’, ‘Cabrillo’, ‘Brilliance’, ‘Fronteras’, and ‘Beauty’ may be adapted to the Lubbock area and do well for commercial strawberry cultivation. However, results are based upon data from a single growing season, and further research and analysis of data will confirm results.
Speakers
SP

Srijana Panta

Texas Tech University
Co-authors
RW

Russ Wallace

TAMU AgriLife Extension
NA
TM

Thayne Montague

Texas Tech University
Friday September 27, 2024 11:00am - 11:15am HST
Coral 3

11:00am HST

WCPM 4 - Evaluation of Insecticide Application Plan to Manage Thrips for Sweet Onions in Texas
Friday September 27, 2024 11:00am - 11:15am HST
Thrips is an important pest of onions that not only reduces yield and quality but also transmit Iris Yellow Spot Virus. The study’s objective was to evaluate different chemical application plans to manage the thrips population in onions. The study was conducted in a split plot design with variety as a main plot and chemical plan as a sub-plot with four replications at Texas A&M AgriLife Research and Extension Center, Uvalde, TX during the 2022-23 season. The variety factor had three levels – Hornet, Mata Hari, and Don Victor. The chemical plan factor also had three levels – weekly application, action threshold (1 thrips per leaf), and control. Although the insect population was low, in general, for the season, the weekly application and action threshold treatments had a lower number of thrips per leaf than the control treatment. The numbers of chemical applications for the weekly application and action threshold were six and three, respectively. The results indicate that growers would save input costs if followed by the action threshold chemical plan. The trial will be evaluated in the 2023-24 season to validate results from the first season.
Speakers
Friday September 27, 2024 11:00am - 11:15am HST
South Pacific 4

11:10am HST

TROP - “Midnite” and “Festival”: Combining Caribbean and African Hibiscus sabdariffa
Friday September 27, 2024 11:10am - 11:20am HST
Hibiscus sabdariffa, regionally referred to as sorrel, is a popular annual fruiting crop in the Caribbean. During the winter holiday season, sorrel calyxes are used for making flavorful and refreshing deep crimson red juices and teas. Through years of breeding and selection among Caribbean and African lines, from Ghana and Nigeria, the University of the Virgin Islands developed and released two new cultivar “Midnite” and “Festival”. “Midnite” has 20% greater production over standard Caribbean cultivars. The dark crimson-black calyxes, of both new cultivars, are full of anthocyanins and bioflavonoids. “Festival” begins bearing a month earlier than photoperiodic cultivars and production can extend to early May. Being day-neutral, “Midnite” can be grown year-round but has heavier production during late summer to late Spring. “Midnite” is being widely used in the U.S. Virgin Islands and has potential to expand its use in other commercial industries.
Speakers
TZ

Thomas Zimmerman

University of the Virgin Islands School of Agriculture
Friday September 27, 2024 11:10am - 11:20am HST
Lehua Suite

11:15am HST

CE 7 - Light Intensity and Zinc Biofortification Effect on Yield and Nutritional Quality of Pea and Radish Microgreens
Friday September 27, 2024 11:15am - 11:30am HST
Zinc (Zn) is a micronutrient crucial for human health, impacting gene expression, cell division, and immune system development. Zinc deficiency affects about 17% of the global population, particularly children, pregnant women, and elderly people, and can lead to disorders and even death. Agronomic biofortification implemented by applying Zn-enriched solutions via fertigation to increase crops Zn content may be a valuable strategy to combat Zn deficiencies. Microgreens, known for their nutrient density, rapid growth cycle, and low phytic acid content, are emerging as promising candidates for Zn agronomic biofortification. However, research is needed to evaluate the effect of factors like light intensity and genotype which can affect Zn accumulation in microgreens. To this purpose, a study was conducted to examine the effect of Zn application rate (0, 5, 10, and 15 mg/L) and light intensity (100, 200, 300, and 400 µmol/m2/s) on yield components, mineral content, and phytochemical profile of pea and radish microgreens. The study revealed that Zn concentration increased with increasing concentration of Zn applied in both species. In peas, a 4-fold increase was observed when applying 15 mg/L of Zn without affecting fresh and dry biomass, while an almost 13-fold increase of Zn content was observed in radish, associated with a 7.8% reduction of fresh biomass and no effects on radish microgreens dry biomass. However, with the increase of Zn content, there was a reduction in Fe concentration in both peas and radish microgreens. The light intensity did not affect Zn content in both species; however, it affected the concentration of macro and other microelements and influenced yield, but the result varied by species. In pea microgreens, low light intensity determined higher fresh biomass but did not affect dry biomass. Instead, the opposite result was observed in radish microgreens; light intensity did not affect fresh yield but increased dry biomass with increasing the level of light intensity applied. Regarding the nutritional profile, total phenols, total antioxidants, and flavonoids increased with increasing Zn concentration and light intensity in both pea and radish microgreens. In conclusion, Zn fertigation effectively enhanced Zn in pea and radish microgreens, and although light intensity had no effect on Zn content, contributed to improve their nutritional profile. These findings provide valuable insights into the production technique of Zn biofortified microgreens and the potential enhancement of their overall nutritional profile using agronomic biofortification techniques.
Speakers
PP

Pradip Poudel

The Penn State University
Pradip
Co-authors
FD

Francesco Di Gioia

The Penn State University
NA
Friday September 27, 2024 11:15am - 11:30am HST
Nautilus 1

11:15am HST

CHMG 2 - Consumer Perceptions of Climate-Smart Products
Friday September 27, 2024 11:15am - 11:30am HST
Climate-Smart Agriculture (CSA) is a broad term referring to agricultural production methods which aim to increase productivity whilst building resiliency to the threats associated with climate change and mitigating greenhouse gas emissions. Examples include cover cropping, conservation tillage, agroforestry, and any other methods which support climate change adaptation and mitigation. A critical yet still understudied component of the advancement of CSA lies in understanding how consumers perceive and interact with climate-smart commodities, and with nearly two-thirds (65%) of Americans believing that climate change is a global emergency, a need to investigate what qualities they attribute to “climate-smart” commodities became clear. This study investigates the perceptions of “climate-smart” commodities amongst American consumers through a national survey with consideration of demographic impacts on definitions. Survey questions investigated if consumers were familiar with CSA, what production qualities they perceived as “climate-smart,” and if they were interested in climate-smart commodities. Questions about production methods were categorized into the three main pillars of CSA set forth by the FAO: adaptation, mitigation, and sustainable intensification. The implications for far-reaching climate-smart food policies, marketing/promotional decisions, and sustainability education efforts for Americans are discussed.
Speakers
AL

Abigail Lauterbach

The University of Georgia
Co-authors
JC

Julie Campbell

University of Georgia
Friday September 27, 2024 11:15am - 11:30am HST
South Pacific 1

11:15am HST

FLOR 3 - The Use of Machine Learning to Develop Refined Foliar Tissue Analysis Standards and Diagnostic Tools for for Petunia
Friday September 27, 2024 11:15am - 11:30am HST
Foliar tissue analysis is utilized to diagnose a crop's nutrient status. For most floriculture crops a survey approach of a small population of plants (n= <25) of healthy appearing plants are used to establish sufficient nutrient standards. While this historical approach offers a baseline for the wide variety of floriculture crops there is a need for scientifically based ranges similar to those available in agronomic crops. For fast-maturing crops, utilizing foliar tissue analysis and correctly interpreting the results is critical in making fertility adjustments when problems arise. Foliar tissue analysis results of petunia (Petunia hybrida) were compiled from a variety of diagnostic and research institutions to account for variations of growing environments and classified into five ranges (deficient, low, sufficient, high, and excessive). To aid in foliar tissue analysis interpretation machine learning models were evaluated for accurate percent correct classification (PCC) into the sample's respective nutrient classification. Four separate machine learning algorithms were performed to analyze the data set including sequential minimal optimization (SMO) of support vector machines (SVMs) and multilayer perceptron (MLP) artificial neural network (ANN), and two decision tree models J48 and Random Forest (RF). Machine learning algorithms were compared to identify significant model nutrients based on a complete foliar tissue analysis report of 11 elements for the observations. The performance of both machine learning algorithms SMO and MLP were determined using PCC and during the cross-validation. By evaluating the foliar tissue concentration dataset of multiple species by 10-fold and 66% split cross-validations, the incorporation of five elements of ranked based on Shannon Entropy (Information Gain) was able to correctly classify tissue concentrations into one of five foliar nutrient classifications greater than traditional statistics. This information provides additional insight as to how examining nutrient relationships can assist in identifying fertility problems and classifying nutrient ranges.
Speakers
PV

Patrick Veazie

NC State University
Co-authors
BW

Brian Whipker

NC State University
NA
Friday September 27, 2024 11:15am - 11:30am HST
Kahili

11:15am HST

ORGH 3 - No-till planting organic dry bean into rolled-crimped cover crops
Friday September 27, 2024 11:15am - 11:30am HST
Consumer demand for organic and locally sourced plant-based protein has created an opportunity for farmers in the Northeast and Upper Midwest who are interested in organic dry bean (Phaseolus vulgaris) production. However, standard practices for organic dry bean production can degrade soil health because of the soil tillage and cultivation used for weed management and harvesting. Such soil disturbance is not only labor and fuel intensive, but it also makes soil vulnerable to extreme weather, which is a major concern given the increased frequency of heavy rain events. Building on success with no-till planting soybean into mechanically terminated cereal rye, a team of researchers and stakeholders from Wisconsin, New York, Maine, and Vermont developed a project to assess dry beans for cover crop-based, organic no-till production. In addition to crop yield and profitability, field experiments focused on assessing weed and disease management. Findings from several experiments show that dry beans can successfully emerge through mulch from cover crops and produce yields that are comparable to standard tillage based organic production. In an experiment conducted at two sites in 2020-2021 and 2021-2022, a cover crop mixture of hairy vetch and cereal rye produced relatively high biomass (>7000 kg/ha), which suppressed weeds (< 500 kg/ha) and resulted in relatively high (2500 kg/ha) organic black bean (cv. ‘Zorro’) yield. Results are congruent with previous research showing that mulch from cover crops can suppress weeds, particularly small seeded annual weeds. In an experiment conducted in 2016-2017 and 2017-2018, we showed that mulch from mechanically terminated cereal rye (Secale cereale) can also reduce the incidence of the fungal disease white mold (Sclerotinia sclerotiorum) in organic no-till planted dry bean. Although mulch from cover crops can suppress weeds and soil borne diseases, achieving the high cover crop biomass production that is necessary for suppression can be challenging. A field experiment was conducted in Wisconsin, New York, Vermont, and Maine in 2022-2023 to test the efficacy of interrow mowing weeds that break through the mulch in the space between crop rows. Preliminary results show that interrow mowing has potential to reduce yield loss from weeds and weed seed production in organic no-till planted dry bean production. Additional research is needed to develop management guidelines for no-till planting organic dry beans into rolled-crimped cover crops.
Speakers
MR

Matthew Ryan

Cornell University
Co-authors
EB

Ellen B Mallory

University of Maine
NA
EY

Eric Youngerman

Cornell University
NA
EF

Erika Filer Everest

Cornell University
NA
ES

Erin Silva

UW-Madison
HD

Heather Darby

University of Vermont
NA
KL

Kristen Loria

Cornell Univ
NA
MH

Madeline Hunter

University of Maine
NA
NA

Nazir Adam Sharifi

Cornell University
NA
SP

Sarah Pethybridge

Cornell University
NA
UM

Uriel Menalled

Cornell University
NA
VM

Virginia Moore

Cornell University
NA
Friday September 27, 2024 11:15am - 11:30am HST
South Pacific 3

11:15am HST

VCM 6 - Optimizing Planting Density of Sweet Corn in Georgia
Friday September 27, 2024 11:15am - 11:30am HST
Currently, most sweet corn in the state of Georgia is produced and shipped wholesale for fresh market consumption. The majority of producers in the state aim for a Fourth of July harvest, and shipper sweet corn is a significant source of income for Georgia vegetable growers. Plant population density is a critical factor for achieving optimal yield while balancing resource inputs, and the commercial standard for sweet corn in the state is 60,000 to 74,000 plants ‧ ha-1. While recent research in the midwestern U.S. suggests that planting densities for processing sweet corn can be pushed above previously recommended ranges to optimize profit, little work has been done in current years concerning fresh market shipper sweet corn in the southeastern region of the country, which differs drastically in soil type and seasonal weather patterns. Therefore, the objective of this study is to re-evaluate current state guidelines for plant population density to optimize marketable yields by manipulating inter- and intra-row plant spacing. To do this, sweet corn (cv. ‘Obsession’) was sown directly to the field in the spring season of 2023 at a rate of 43,000 to 107,000 plants ‧ ha-1, which was achieved with sowing patterns in either two or three rows per bed top (91 cm or 46 cm apart, resp.), and five within-row spacings ranging from 15 cm to 25 cm at 2.5 cm increments. The field was managed according to the University of Georgia's irrigation, fertilizer, insect, and disease management guidelines. At harvest, the number, size, and tip fill of ears were collected, with marketable ears categorized based on USDA Fancy grading standards for a minimum length of 15 cm and unfilled kernels at tips covering less than one-fourth cob length. A significant increase in marketable yield was associated with the number of rows but not within-row spacing, with an average increase of 24% in three-row treatments (p < 0.05). There was not a significant difference in unmarketable yield between row treatments. Preliminary results indicate that plant population density for shipper sweet corn in Georgia can be increased by adding a third row while maintaining fresh market quality.
Speakers
HM

Hayley Milner

University of Georgia
Co-authors
JC

Juan Carlos Diaz Perez

University of Georgia
NA

Nirmala Acharya

University of Georgia
NA
SV

Simerjeet Virk

University of Georgia
NA
TM

Ted McAvoy

University of Georgia
NA
Friday September 27, 2024 11:15am - 11:30am HST
South Pacific 2

11:15am HST

VSF 5 - Active vs. Passive Row Cover Management: Impacts on Abiotic Growing Conditions, Yield, and Pests on Overwintering Strawb
Friday September 27, 2024 11:15am - 11:30am HST
Locally produced strawberries have outstanding market potential. Yet their production in the north-central US has declined, partly due to risks associated with the traditional matted-row system. While the plasticulture system offers promise, challenges like plug plant availability in late summer persist. Farmers may choose to use bare-root plants and plant in the summer. However, the high labor demand for planting bare-root plants on plastic and the intensive plant care in the summer have limited the use of plasticulture systems to small-scale operations. High tunnels are widely adapted for strawberry production worldwide. This structure protects plants from strong winds and rainfall, providing additional heat units and moderate frost protection. Successful implementation in Indiana, particularly with fall-planted strawberries, has demonstrated significant yield potential. In our initial exploration, an active row cover management strategy, i.e., covering and uncovering the plants daily in the winter months according to temperatures, was employed during winter months. Although the management approach optimized the winter environment for plant growth, it added labor in crop management, and it may not be feasible for farmers who are not on-site during winter months. This study compares four winter cover management strategies in the 2021-2022 and 2022-2023 seasons: No cover (row covers were not used in the entire winter), Active with hoops (row covers were actively managed daily and placed on hoops), Passive with hoops (the beds were covered during the coldest period, row covers were not removed during the day and were placed on hoops), and Passive without hoops (the beds were covered during the coldest period, row covers were not removed during the day and were placed directly on plants). The study found that No cover resulted in lower minimum temperatures and higher average daily PAR. The active management treatment exhibited the highest relative humidity. Marketable strawberry yields were not significantly different among the covering treatments. However, aphid density was notably higher under covers compared to the no-cover treatment. Our findings indicate that active row cover management during winter was not necessary in the strawberry production system, as it did not significantly increase yield compared to passive management strategy or absence of row covers. Furthermore, the passive management strategy, while potentially advantageous in terms of temperature regulation, was not recommended due to the associated risk of elevated aphid populations.
Speakers
WG

Wenjing Guan

Purdue University
Co-authors
LI

Laura Ingwell

Purdue University
NA
SW

Samantha Willden

Purdue University
NA
Friday September 27, 2024 11:15am - 11:30am HST
Coral 3

11:15am HST

WCPM 4 - Are selective insecticides compatible with Bemisia tabaci biocontrol efforts in controlled environments?
Friday September 27, 2024 11:15am - 11:30am HST
Generalist predators are known for their significant contribution to suppression of major crop pests in controlled environments and beyond. Given that insecticides are one pillar of many Integrated Pest Management (IPM) programs, their compatibility with biocontrol efforts is essential for developing a successful IPM program. Knowledge gaps persist regarding selective insecticides' non-target impacts on whitefly natural enemies that can jeopardize its biocontrol efforts. In this study, we exposed adult predators to commercially available insecticides (Cyantraniliprole and Pyriproxyfen) using multiple laboratory approaches to assess their effects on survivorship, predation, and changes in prey selection in response to insecticides. Two major whitefly predators were evaluated including, Hippodamia convergens (Coleoptera: Coccinellidae) and Geocoris punctipes (Hemiptera: Geocoridae), to estimate survivorship and consumption of whitefly nymph, Bemisia tabaci (Hemiptera: Aleyrodidae). Our result indicates that while pyriproxyfen had a negligible effect on the predators, cyantraniliprole exposure directly affected H. convergence by reducing survivorship duration and indirectly influenced both predators by reducing prey consumption and altering prey preference. Overall, pyriproxyfen demonstrated minimal impact on predators, while cyantraniliprole adversely influenced mortality and indirect foraging effects under controlled laboratory conditions. Hence, our findings highlight that even highly selective insecticides could have a sub-lethal impact on natural enemies, jeopardizing their contribution to pest control, and warranting future efforts to better integrate them into IPM programs.
Speakers Co-authors
AP

Albertha Parkins

University of Georgia
NA
JM

Jason M Schmidt

University of Georgia
NA
Friday September 27, 2024 11:15am - 11:30am HST
South Pacific 4

11:20am HST

TROP - Metabolomic Survey of Puffy Skin Date Fruit
Friday September 27, 2024 11:20am - 11:30am HST
Date palm, Phoenix dactylifera L., is one of the oldest fruit crops grown in the arid regions of the Arabian Peninsula, North Africa and the Middle East and plays a significant role in the economy, society, and environment in these areas. ‘Medjool’ is considered one of the most desirable date varieties worldwide. Skin separation, also known as “puffy skin”, is a widespread phenotypic phenomenon mostly seen in soft varieties such as‘Medjool’ and ‘Barhee’. Skin separation is a market defect that is a commercial disadvantage. In this study, we conducted a metabolomic study of 'Medjool’ fruits at the date genebank maintained in Thermal, California by the United States Department of Agriculture Agricultural Research Service. Date fruit were harvested at the tamar stage (the fruit development stage in which the puffy skin phenotype develops). The metabolomes found in mature date fruits exhibiting non-puffy and puffy phenotypes were characterized. In this study, targeted central carbon metabolism analysis was carried out to identify 126 total metabolites with 95 significant metabolites (p-value < 0.05) (75.4%). Principal Component Analysis (PCA) was carried out, revealing that specific metabolites were associated with the non-puffy skin phenotype, and other metabolites with the puffy skin phenotype.. These metabolomes included those associated with skin elasticity and integrity, supporting studies suggesting the involvement of mechanical properties of date fruit skin.
Speakers
YH

Yoko Hiraoka

University of California Riverside/USDA-ARS
Co-authors
ER

Esteban Rodriguez

National Clonal Germplasm Repository for Citrus and Dates, United Stated Department of Agriculture, Agricultural Research Service, U.S.
NA
RK

Robert Krueger

National Clonal Germplasm Repository for Citrus and Dates, United Stated Department of Agriculture, Agricultural Research Service, U.S.
NA
Friday September 27, 2024 11:20am - 11:30am HST
Lehua Suite

11:29am HST

Vegetable Breeding (VGBR)
Friday September 27, 2024 11:29am - 12:30pm HST
The Power of Breeding and Genetics in Controlled Environment Horticulture - Krishna Bhattarai
Novel Summer Squash: Breeding Tromboncino Types for U.S. Markets - James Myers
Mapping QTL for Bacterial wilt resistance and plant height in Tomatoes - Dilip Panthee
Effects of Prolonged Photoperiod on Chile Pepper Plant Architecture and Growth Habit - Shahab Nourbakhsh
Seasonal Lettuce Germplasm Trials in Northeast Florida Hydroponics - Evelyn Fletcher
Marker Development for Cadmium Accumulation in Spinach - Danyelle Forte
Moderator
SN

Shahab Nourbakhsh

New Mexico State University
Friday September 27, 2024 11:29am - 12:30pm HST
Coral 1

11:30am HST

TROP - Identifying the formation of aroma compounds in mango using a multi-omics approach
Friday September 27, 2024 11:30am - 11:40am HST
Mango (Mangifera indica L.) is a fruit renowned for its delectable flavor, making it a staple in tropical and subtropical regions and the second most significant fruit crop in horticulture. Despite its widespread popularity, the specific compounds responsible for its distinctive aroma remain elusive. Our study aimed to bridge this gap by employing untargeted metabolomics and proteomics approaches to investigate aroma compound biosynthesis in three mango cultivars: 'Ah Ping', 'Rosa', and 'Rosigold'. Through integrated metabolomics and proteomics analysis, we identified key pathways and enzymes involved in aroma compound biosynthesis. Fatty acid metabolism, amino acid metabolism, pentose and hexose metabolism, and terpenoid metabolism emerged as pivotal pathways influencing mango flavor diversity. In 'Ah Ping', upregulation of lipoxygenase, hydroperoxide lyase, and alcohol dehydrogenase led to the accumulation of C6 and C9 volatile compounds, contributing to its distinct aroma profile. Conversely, 'Rosa' exhibited varied contents of straight-chain volatile compounds facilitated by the upregulation of enzymes involved in fatty acid degradation. Amino acid metabolism played a crucial role, with glutamate, valine, and phenylalanine serving as precursors for the biosynthesis of butyl esters and aromatic compounds in all three cultivars. Differential expression of enzymes such as aminotransferase and decarboxylase further modulated aroma compound production. Additionally, variations in furan and pyran volatile compounds were linked to differentially expressed enzymes in pentose and hexose metabolism. Our findings provide a comprehensive metabolic and proteomic map elucidating the biosynthesis of specific aroma compounds across mango cultivars. By unraveling the molecular mechanisms underlying mango flavor, this study offers valuable insights for breeding programs aimed at enhancing mango varieties with superior flavor quality. Overall, our research sheds light on the interplay between metabolism and aroma compound biosynthesis in mango, paving the way for targeted breeding strategies and improved mango flavor profiles.
Speakers
YW

Yu Wang

University of Florida
Co-authors
JH

Jonathan H Crane

University of Florida, TREC
XL

Xin Liu

University of Florida
NA
XW

Xingbo Wu

University of Florida
NA
Friday September 27, 2024 11:30am - 11:40am HST
Lehua Suite

11:30am HST

VGBR - The Power of Breeding and Genetics in Controlled Environment Horticulture
Friday September 27, 2024 11:30am - 11:40am HST
Controlled environment (CE) horticulture production has shown its potential to cope with the impact of climate change such as rising temperatures and declining water availability. Drives like “locally grown”, and “food miles reduction” favor CE-based food production which represents a $50 billion market for fresh, local, and sustainable food. CE production systems use advanced technology for climate control and mechanized growing practices for which infrastructure and software development have taken a good start. Contrastingly, the breeding and development of plants designed to best perform in CEs to reduce energy usage, allow automation, and increase profits are just beginning. The US CE producers can benefit from the breeding and development of new cultivars with modified stature that offer high-density planting and shortened crop cycles, ease in maintaining and harvesting, and allow automation. Utilization of plant genetics to breed for plant statures will increase crop diversity in CEs. Additionally, discovering new genetics in plant germplasms to enhance crop quality for nutrition, flavor, taste, color, and texture through breeding can meet consumer needs for fresh, high-quality, nutritious, and sustainably produced food. Several other opportunities exist where leveraging genetics to breed new crops that produce nutraceuticals, biofuel, macro and micronutrients, and bioactive compounds can sustain the CE horticulture industry, feed the increasing population, improve health, and cope with climate change.
Speakers
Friday September 27, 2024 11:30am - 11:40am HST
Coral 1

11:30am HST

CE 7 - Evaluation of Liquid Organic Fertilizers for Containerized Production of Leafy Greens in a Controlled Environment
Friday September 27, 2024 11:30am - 11:45am HST
Organic farming practices, such as the use of organic substrates, fertilizers, pesticides, and biological control, are gaining popularity in controlled environment agriculture (CEA) since soilless production was approved for organic certification in the US. Our past study showed that liquid organic fertilizers are more effective than substrate-incorporated compost fertilizers. Although many liquid organic fertilizers are commercially available, they vary widely in their nutritional composition. Therefore, selection of a suitable fertilizer can be complicated and confusing for CEA growers. The current study aimed to evaluate the effectiveness of different liquid organic fertilizers and compare their performance with that of a synthetic fertilizer for growing lettuce in two different containerized hydroponic systems. Two greenhouse experiments were conducted in a randomized block design with five replicates. In Experiment 1, two types of container (regular container and Dutch bucket) and three fertilizers (earthworm castings and kelp (ECK), molasses with other natural plant extracts (MPE), and hydrolyzed fish protein (HFP)) were considered. The fertilizers were selected from the Organic Materials Review Institute (OMRI) list based on their nutrient profile and reports from other studies. In Experiment 2, selected liquid organic fertilizers (ECK, MPE) were compared with a commercial synthetic fertilizer (CSF). In Experiment 1, ECK performed better, resulting in 28% greater fresh weight, 20% greater dry weight, 48% greater leaf area, 26% greater shoot width, 126% greater average root fresh weight, and 47% greater root length in containerized production compared to the Dutch bucket system. No significant growth difference was observed between MPE and HFP. In Experiment 2, there was no significant growth difference between ECK and CSF; however, the shoot width, leaf area, and dry weight of lettuce were significantly lower with MPE treatments compared to ECK. Results show that ECK performed similarly or better than synthetic fertilizer for growing lettuce in these container hydroponic systems. The findings of this study indicate that a single organic fertilizer could be used instead of several for organic leafy green production in soilless substrate.
Speakers
US

Uttara Samarakoon

The Ohio State University
Co-authors
JM

Joanna Moine

The Ohio State University
NA
MC

Milon Chowdhury

The Ohio State University
OW

Oliver Watson

The Ohio State University
NA
Friday September 27, 2024 11:30am - 11:45am HST
Nautilus 1

11:30am HST

CHMG 2 - Setting Priorities for Managing Extension Work and Home Life
Friday September 27, 2024 11:30am - 11:45am HST
Extension careers are uniquely challenging for work/life balance. Extension professionals frequently work with stakeholders outside the university and spend a significant amount of time traveling to give presentations and build relationships. In consumer horticulture, an added stress is that most educational programming is scheduled for evenings and weekends. Overflowing email inboxes further compound the stress. High rates of exhaustion and burnout have been documented in Extension professionals. The problem is one of high demand and limited resources. Extension professionals are expected to navigate the problem of scarce resources by individually setting priorities and saying no to low impact requests. A new prioritization method will be introduced that is based upon real estate appraisal law. The highest and best use analysis can be adapted for setting priorities for the busy Extension professional regardless of career stage. This session will emphasize amending position descriptions to articulate clear boundaries, setting aside time to be physically and mentally rested, and prioritizing high impact projects. The highest and best use analysis is meant to be customized for each individual and takes into account unique traits such as introversion/extroversion, age, and topic expertise.
Speakers
avatar for Esther McGinnis

Esther McGinnis

Extension Horticulturist/Director of the Extension Master Gardener Program, North Dakota State University
I am the Extension Horticulturist and Director of the Extension Master Gardener Program.
Friday September 27, 2024 11:30am - 11:45am HST
South Pacific 1

11:30am HST

FLOR 3 - Increasing the Nighttime Lighting Duration Can Hasten Flowering of Long-day Plants
Friday September 27, 2024 11:30am - 11:45am HST
Low-intensity (≈ 2 μmol·m−2·s−1) photoperiodic lighting is often delivered at night to promote flowering of long-day greenhouse ornamentals when natural days are short. Adding sufficient far-red (FR) light to red (R) light is necessary for the most rapid flowering in some crops, including snapdragon (Antirrhinum majus) and petunia (Petunia × hybrida). Specialty light-emitting diodes (LEDs) that include R FR light are effective at floral promotion but cost-prohibitive, whereas common warm-white (WW) LEDs lack sufficient FR light and can delay flowering. Because the duration to saturate flowering is longer than currently used (e.g., 4–8 hours) for some long-day plants, we conducted a replicated greenhouse experiment to determine how the WW or R FR LED lighting duration influenced flowering. We grew snapdragon ‘Liberty Classic Yellow’, petunia ‘Easy Wave Burgundy Star’, and petunia ‘Wave Purple Improved’ under truncated 8-hour natural short days with or without WW or R FR (1:1) LEDs operating for 0, 4, 8, 12, or 16 hours in the middle of each night throughout the experiment. Snapdragon flowered 13–16 days earlier under R FR LEDs than under WW LEDs regardless of the lighting duration. Increasing the lighting duration from 0 to 16 hours decreased flowering time by up to 16 days and decreased plant height and leaf number at flowering under R FR LEDs, but not under WW LEDs. For petunia ‘Easy Wave Burgundy Star’, although WW LEDs delayed flowering by 6–13 days but promoted lateral branching compared to R FR LEDs, the gap in flowering time narrowed as the lighting duration increased from 4 to 16 hours. Increasing the lighting duration improved the efficacy of WW LEDs, but not R FR LEDs. Flowering of petunia ‘Wave Purple Improved’ was unaffected as the lighting duration increased from 4 to 16 hours regardless of the lamp type and was delayed by 6–10 days under WW LEDs than under R FR LEDs. For both petunia cultivars, flowering time was similar under 16-hour WW LEDs and 4-hour R FR LEDs. In conclusion, increasing the nighttime lighting duration increased the efficacy of WW LEDs at promoting flowering of petunia and increased the efficacy of R FR LED lamps at promoting flowering of snapdragon. Delivering WW LEDs all night long can minimize flowering delay in petunia compared to R FR LEDs. In contrast, sufficient FR light was indispensable to promote flowering of snapdragon, for which WW LEDs were ineffective.
Speakers
QM

Qingwu Meng

University of Delaware
Co-authors
TK

Thomas Kramer

University of Delaware
NA
Friday September 27, 2024 11:30am - 11:45am HST
Kahili

11:30am HST

VCM 6 - Boosting Sweet Corn Yields: The Power of Biochar and Fertilizers Unveiled
Friday September 27, 2024 11:30am - 11:45am HST
This study explored the efficacy of biochar, derived from paper mill waste, in enhancing soil properties, plant growth and yield in sweet corn when used with organic (poultry litter) or inorganic fertilizers. Conducted in spring 2023, the field trial assessed biochar application rates (0, 10, 15, and 20 tons/acre) combined with fertilizers supplying 225 lbs N/acre in a randomized complete block design with four replications. Our results indicate that biochar's effectiveness is limited when used alone but significantly affects soil nutrients and crop outcomes in combination with fertilizers. Inorganic fertilizers, compared to organic, were more effective in improving yield metrics such as ear number, weight, and width. In addition, our findings suggest that the interaction of biochar and fertilizer type significantly influences soil nutrient levels. Biochar and inorganic fertilizer generally exhibited a strong negative correlation with nutrients like nitrogen (N), indicating a notable decrease in N soil content with lower biochar application rates. Suggesting that biochar can mitigate nutrient depletion when combined with inorganic fertilizers. Conversely, when biochar is applied alongside organic fertilizers, the outcomes vary across different nutrients. For magnesium (Mg) and calcium (Ca), positive correlations emerge at higher application rates, hinting at biochar's role in enhancing the bioavailability of these nutrients in organically fertilized soils. Regarding plant growth and development, the analysis revealed that the interaction between fertilizer type with biochar and biochar rate alone had no significant effect on most measured growth parameters. However, the fertilizer type used did significantly affect some growth parameters. Specifically, plants grown with organic fertilizer had significantly higher fresh weight of roots and total dry plant weight than those grown with inorganic fertilizer. It was found that the highest rate of biochar (20 tons/A) raised soil pH significantly at 90 days, reaching 6.65 pH in the inorganic treatment and 7.0 pH in the organic treatment. The pH was lowest in the treatments without biochar (0 tons/acre) at 90 days after application (5.1 pH inorganic and 6.0 pH organic treatments respectively). Furthermore, biochar application was linked to increased soil microbial activity, as evidenced by CO2 burst measurements. These significantly rose with higher biochar rates under both fertilizer regimes, albeit without a significant interaction effect between biochar and fertilizer type on CO2 burst. These findings suggest that integrating biochar with fertilization strategies can enhance soil health and sweet corn production, offering a sustainable approach to managing soil nutrients and improving crop yield.
Speakers
ES

Emilio Suarez Romero

University of Georgia
Co-authors
HY

Henry Y Sintim

University of Georgia
NA
JC

Juan Carlos Diaz Perez

University of Georgia
KC

Kate Cassity Duffey

University of Georgia
NA
TM

Ted McAvoy

University of Georgia
NA
Friday September 27, 2024 11:30am - 11:45am HST
South Pacific 2

11:30am HST

VSF 5 - Performance of Containerized Strawberries (Fragaria x ananassa Duch.) in a Greenhouse Environment
Friday September 27, 2024 11:30am - 11:45am HST
The horticulture industry has seen an increase in the use of greenhouses as an alternative protected systems to grow strawberries (Fragaria ×ananassa Duch.). Growing strawberries in a greenhouse provides the opportunity for earlier and out-of-season harvesting. However, there is limited research on the phenological and physiological performance of strawberries grown in containers under greenhouse conditions. Therefore, this experiment aims to evaluate the phenological and physiological performance of containerized strawberries grown in a greenhouse. In this study, two day-neutral strawberry cultivars, ‘Albion’ and ‘San Andreas’, were planted in 1-gallon nursery pots using 100% pine bark substrate and evaluated for a 5-month growing season. The phenological stages of all flower buds were recorded daily on five selected plants per cultivar. Monthly data was collected on biomass and diurnal photosynthesis. The yield of all plants was recorded, and fruits were separated into marketable and culled categories. During mid-season plants became infected with black root rot (Pythium spp.), and the results reflect the effects of the disease progression. Although the flower phenology was similar between cultivars throughout the production cycle, differences were observed in biomass accumulation and yield. ‘San Andreas’ showed higher growth over time and a decreased proportion of cull fruits during the Pythium infection. The cultivars evaluated showed similar trends in physiological processes, such as assimilation rate, evapotranspiration, intercellular carbon, stomatal conductance, leaf vapor pressure deficit, and quantum efficiency of photosystem II. Although not consistent, ‘San Andreas’ showed significantly higher values for some physiological parameters. These results indicate that strawberry growth and yield differ between cultivars in the greenhouse environment, which could be related to physiological factors that can ultimately translate to differences in disease susceptibility and performance The initial preliminary results of the first experiment indicates that strawberries can be cultivated with satisfactory results in a greenhouse. This alternative method can offer extended growing seasons, allowing for controlling environments, better disease control management, and easier pest control. Moreover, the portability of containers provides flexibility for the producer to arrange plants for space utilization.
Speakers
CB

Caroline Blanchard

Research Associate II, Auburn University
Co-authors
BC

Bernardo Chaves Cordoba

Auburn University
NA
MR

Melba Ruth Salazar Gutierrez

Auburn University
NA
Friday September 27, 2024 11:30am - 11:45am HST
Coral 3

11:30am HST

WCPM 4 - Plants Under Regulation; A North Carolina Perspective
Friday September 27, 2024 11:30am - 11:45am HST
State and federally regulated weeds pose significant challenges to agricultural economies worldwide, impacting crop yields, production costs, and overall farm profitability. Some estimates have their economic impact upwards of $30 billion dollars annually. Regulated plants can encroach upon public and private property, and cultural and recreational areas, which not only diminishes their aesthetic appeal and usability, but also displaces other native plants and animals. State and federal regulatory agencies operate within a legal framework for setting rules that allow for the control of regulated plants. Regulatory rules apply measures that help preserve these public and private spaces by addressing infestations of noxious plants. Management strategies of active infestations can range from controlling future or current spread to full on eradication. While eradication of a noxious plant may be the gold standard to strive for, it is also the most time consuming and costliest strategy. Often, two commonly employed solutions, aside from eradication, are; either managing or controlling an infestation. Managing is where the infestation isn’t increasing in geographic area. The periphery is fought to limit further spread. Controlling an infestation goes beyond managing, where a push is made to reduce the geographic area and steers the infested area toward an eradication track. The more stringent (eradication) a strategy becomes, the higher the cost and the longer it will take. The classic invasion curve describes this situation perfectly where the longer an infestation goes before it is identified, the more expensive and longer it will take to eradicate, if at all. Chemical applications, IPM and cultural control mechanisms are used to fight active infestations. Other tools in the regulatory tool bag include inspection of agricultural commodities and issuance of phytosanitary certificates, nursery inspections and certification, active survey and the use of quarantines and limited research permits. North Carolina has multiple active projects working towards eradication and control. Witchweed (Striga asiatica) populations have been present in NC and SC since its introduction in 1955. Witchweed, if left unchecked, has the potential to devastate the midwestern corn belt, which was the primary reason for its regulation. At that time North Carolina had approximately 400,000 infested acres. Today we have 2,000 infested acres. Other noxious weeds on the eradication path are wooly frogsmouth (Philydrum lanuginosum) and yellow floating heart (Nymphoides peltata). Both species have been aggressively treated in their limited distribution within the state.
Speakers
JD

Jarred Driscoll

North Carolina Dept. of Ag.
Friday September 27, 2024 11:30am - 11:45am HST
South Pacific 4

11:40am HST

TROP - Establishment of Avocado trees in the United States Virgin Islands
Friday September 27, 2024 11:40am - 11:50am HST
Avocado (Persea americana Mill.), also known as pear in the Caribbean, is a staple fruit in the United States Virgin Islands (USVI) and has one of the fastest expanding markets in Europe and North America. Multiple West Indian cultivars exist. The objective of this study was to evaluate the establishment of 13 avocado varieties in the USVI. Thirteen cultivars were sourced from Florida, these cultivars are ‘Brogdon’, ‘Catalina’, ‘Choquette’, ‘Day’, ‘Donnie’, ‘Lula’, ‘Marcus Pumpkin’, ‘Monroe’, ‘Oro Negro’, ‘Pollock’, ‘Russell’, ‘Thompson Red’, and ‘Uh La La’. These grafted cultivars were planted on July 7, 2022, at 5.5 m spacing with drip irrigation installed as a 1 m diameter around the trees. Data on vertical stem growth after planting and the number of lateral shoots was collected monthly. Walk-throughs are conducted biweekly to identify when each cultivar begins flowering. Similarities in vertical stem growth and flowering were observed after 2 years. ‘Day’, ‘Marcus Pumpkin’, ‘Monroe’, ‘Oro Negro’, ‘Russell’, and ‘Thompson Red’ all grew an average of 98 cm. ‘Brogdon’ grew 137 cm which was the most vertical growth of all the cultivars and ‘Catalina’ grew only 43 cm which was the least. By the second year ‘Brogdon’, ‘Catalina’, ‘Oro Negro’, ‘Pollock’, ‘Russell’, and ‘Thompson Red’ all began flowering from January through April with ‘Pollock’ flowering the earliest in January. Avocado cultivars ‘Day’, ‘Russell’, ‘Oro Negro’, ‘Thompson Red’, and ‘Marcus Pumpkin’ have shown similarities in vertical growth over 20 months with only ‘Oro Negro’, ‘Russell’, and ‘Thompson Red’, flowering during the same months.
Speakers
SJ

Samuel Joseph

University of the Virgin Islands
NA
Co-authors
TZ

Thomas Zimmerman

University of the Virgin Islands School of Agriculture
Friday September 27, 2024 11:40am - 11:50am HST
Lehua Suite

11:40am HST

VGBR - Novel Summer Squash: Breeding Tromboncino Types for U.S. Markets
Friday September 27, 2024 11:40am - 11:50am HST
Cucurbitaceae family squash and pumpkins are all New World domesticates from different parts of the Americas. While many types are eaten as winter squash at full maturity, others – termed summer squash – are used as vegetable where the immature fruit is eaten. The summer squash we are most familiar with belong to the species Cucurbita pepo. The immature fruit of C. maxima and C. moschata are sometimes used as summer squash and a few land race types have been developed mainly for summer squash use. ‘Tromboncino’ (also called Trombetta or Zucchetta Rampicante), is one such C. moschata summer squash from the Ligura region of Italy. It is most closely related to the butternut winter squashes. Originally domesticated in the tropical lowlands of Middle America, it is more tolerant of high temperatures, humidity and pest and diseases. Tromboncino is essentially a butternut squash with an extended neck that has been adapted to use as an immature vegetable but can also be used as a winter squash. The heritage varieties of Tromboncino are long-vined with prolific fruit production and produce few seeds. The seeds are found in a bulb at the end of the fruit, leaving a long seedless neck for culinary preparation. It has a firmer, meatier texture and a flavor profile that is more similar to a mature butternut squash. Tromboncinos are at their highest quality when used at 6-12" long, but they can be eaten at later stages until fully mature. The main breeding objective of the OSU vegetable breeding program was to develop a tromboncino type with better adaptation to the cool summers of Western Oregon, shift plant architecture to a bush plant habit while retaining prolificacy, and shorten fruit length for fresh market production. Another objective was to combine the tromboncino type with skin colors other than the traditional tan color of the heritage variety. We have been able to accomplish most objectives although the plant architecture is not yet comparable to the bush habit of C. pepo summer squash. Some types have dark green as well as yellow skin colors (conditioned by the precocious yellow gene). Two advanced lines are in the process of being released.
Speakers
JM

James Myers

Oregon State University
Co-authors
EL

Emma Landgraver

Oregon State University
NA
JD

Joel Davis

Oregon State University
NA
Friday September 27, 2024 11:40am - 11:50am HST
Coral 1

11:44am HST

Plant Biotech (PB)
Friday September 27, 2024 11:44am - 12:25pm HST
PoDRM2: Unveiling a Key Regulator of Biomass Production and Starch Accumulation in Arabidopsis thaliana - JianHuang
Efficient high molecular weight DNA isolation and whole genome sequencing of papaya for molecular applications - Jon Suzuki
Tissue Culture Regeneration of Miscanthus Sinensis ’Gracillimus’ - Kedong Da
In Vitro Shoot Regeneration Protocol For Southern Highbush Blueberry (SHB) Cultivars - Anandi Karn





Friday September 27, 2024 11:44am - 12:25pm HST
South Pacific 3

11:45am HST

PB - PoDRM2: Unveiling a Key Regulator of Biomass Production and Starch Accumulation in Arabidopsis thaliana
Friday September 27, 2024 11:45am - 11:55am HST
Starch, a vital dietary component and crucial for bio-ethanol generation, is synthesized by plants during photosynthesis. Augmenting starch output holds promise for human and animal nutrition, as well as bioenergy. Our previous work involved cloning the homolog gene DRM2 from Purslane and subsequently overexpressing PoDRM2 in Arabidopsis. Comparative analysis between wild-type Columbia and homozygous PoDRM2 transgenic lines revealed a substantial increase in plant size and nearly a 90% rise in fresh biomass per plant in PoDRM2 lines, indicating a potentially heightened efficiency in photosynthesis. We conducted further investigations into starch synthesis and accumulation in leaves. Iodine staining revealed that PoDRM2 transgenic Arabidopsis lines accumulated significantly more starch than the control under both dark and light conditions. Additionally, total carbohydrates in the leaves of transgenic lines more than doubled that of the wild type. Furthermore, PoDRM2 lines exhibited higher chlorophyll content compared to the control. These findings strongly indicate that PoDRM2 serves as a crucial regulator of starch accumulation. PoDRM2, encoding a methyltransferase, was implicated in altering the methylation status of over 2,500 genes through genome-wide bisulfite sequencing. Notably, 55 out of 61 genes involved in the photosynthesis pathway were affected, underscoring the significant role of DNA methylation in regulating starch accumulation and photosynthesis in plants.
Speakers
JH

Jian Huang

Virgina State University
Friday September 27, 2024 11:45am - 11:55am HST
South Pacific 3

11:45am HST

FLOR 3 - Extended Storage of Cut Flowers Using Sub-zero Temperature
Friday September 27, 2024 11:45am - 12:00pm HST
The cut flower industry needs postharvest techniques that allow for extended storage of fresh cut flowers to meet consumer demands. We evaluated the use of sub-zero storage temperature (-0.6 °C) to maintain viable flowers with improved or comparable vase life to flowers stored at the industry standard (4 °C) without sacrificing aesthetic appeal. The vase life of 17 commercially important cut flower species: alstroemeria, anemone, campanula, carnation, chrysanthemum, delphinium, freesia, gerbera, gypsophila, larkspur, lily, lisianthus, ranunculus, rose, stock, sunflower, and tuberose, when stored dry at -0.6 °C for durations of 4, 8, and 12 weeks was comparable to or longer than when stored at 4 °C. Tuberose stems were not viable after holding for any storage duration or temperature. Stems of carnation benefited from an 8-hour pre-storage pulse with a hydrating solution and maintained a similar vase life to non-stored control stems when stored for 4 weeks at -0.6 °C. Conversely, rose stems only maintained similar vase life to non-stored control stems when held at 4 °C for all pre-storage pulsing solutions (water, hydration or holding solution). Vase life of lily and chrysanthemum declined for all pre-storage pulsing solutions and stems only remained viable after 8 weeks storage when held at -0.6 °C. Additionally, stored chrysanthemum and lily stems had a longer vase life when stored at -0.6 °C than when held at 4 °C after 4- and 8-weeks storage, respectively, for all pre-storage pulsing solutions. Experiment 3 further evaluated carnation, lily, and rose stems with and without a pre-storage acclimation period at 4 °C for either 24 hours or 1 week prior to extended storage durations of 4, 6, or 8 weeks. Holding stems at 4 °C for 1 week prior to extended storage reduced vase life of all species. Rose stems remained viable after 8 weeks of extended storage when held at -0.6 °C, but only when no pre-storage hold was used. Lily and rose stems were not viable beyond 4-week storage durations when held at 4 °C, but remained viable with no pre-storage holding period after 8 weeks at -0.6 °C. Carnation stems maintained longer vase life irrespective of a pre-storage holding period when stored at -0.6 °C. Through this work we show that that many species of cut flower may be held at sub-zero temperature with improved or comparable vase life to the industry standard of 4 °C.
Speakers
JD

John Dole

North Carolina State University
Co-authors
JK

Jennifer Kalinowski

North Carolina State University
NA
Friday September 27, 2024 11:45am - 12:00pm HST
Kahili

11:45am HST

VSF 5 - Influence of Soil Disinfestation and Beneficial Bacterial Treatments on Anthracnose Fruit Rot Disease and Strawberry Yield
Friday September 27, 2024 11:45am - 12:00pm HST
Anthracnose fruit rot (AFR) caused by Colletotrichum acutatum is a major strawberry pathogen in the U.S. affecting both perennial and annual systems. This pathogen can survive in the soil rhizosphere from the previous seasons. Anaerobic soil disinfestation (ASD), an alternative to chemical fumigation methods, has been shown to effectively suppress a wide range of soilborne pests. Beneficial bacteria, such as Bacillus spp., are important biocontrol agents due to their capacity to reduce the growth of pathogens while also promoting plant growth. We proposed that ASD, beneficial bacteria, and their combinations could reduce fruit rot diseases of strawberries and improve crop yield and fruit quality parameters. A trial was conducted using a split-plot design with four replicates at the Hampton Roads AREC, Virginia Beach, VA. ‘Chandler’ strawberry plug plants were planted in various treatments as stated below: non-disinfested field plots (Control); field plots treated with Pic-Clor60 at 196 kg/ha (preplant soil fumigant) (Pic); field plots treated with ASD alone. Additionally, strawberry plants in each of these main treatments were treated with one of the following sub-treatments: no beneficial bacteria (untreated control), Bacillus velezensis only; TerraGrow (a mixture of five Bacillus spp.) at 1.7 kg/ha only; and TerraGrow 1.7 kg/ha applied 4 hours post Oxidate 5.0 (27% hydrogen peroxide, 5% acetic acid and 5% peroxyacetic acid) at 23,385 L/ha. Fruits were harvested twice per week starting 5 April through 20 June, 2023. Harvested fruits in each replicate or sub-plot were sorted into marketable and non-marketable categories. Non-marketable fruits included diseased fruits, small fruits or deformed fruits. Fruit weights were summed for the season by replicate and expressed as g/plant. Fruit firmness and total soluble solids (TSS) were measured on five representative marketable fruits per replicate once per harvest week and data were averaged for the season. For AFR, the weight of diseased fruits decreased significantly in sub-plots treated with B. velezensis, TerraGrow, and TerraGrow post Oxidate compared with the untreated control. In general, the ASD treatment significantly decreased the weight of AFR diseased fruits compared to the control and Pic-Clor 60 fumigation treatments. Fruit from ASD treated plots showed increased firmness and higher Total Soluble Solids values compared to Pic-Clor 60 plots. However, the marketable and total yield was lower in the ASD plots compared with other treatments. Our findings indicate that the utilization of beneficial microorganisms with ASD has the potential to reduce fungal diseases in annual hill strawberry production system.
Speakers
JS

Jayesh Samtani

Associate Professor, Virginia Tech
Co-authors
BA

Baker Aljawasim

Virginia Tech
NA
CM

Chuansheng Mei

Institute for Advanced Learning and Research
GY

Gabriel Yeboah

Virginia Tech, Hampton Roads AREC
NA
PR

Patricia Richardson

Virginia Tech, Hampton Roads AREC
NA
RC

Robert Chretien

The Institute for Advanced Learning and Research
NA
SL

Scott Lowman

The Institute for Advanced Learning and Research
NA
Friday September 27, 2024 11:45am - 12:00pm HST
Coral 3

11:50am HST

VGBR - Mapping QTL for Bacterial wilt resistance and plant height in Tomatoes
Friday September 27, 2024 11:50am - 12:00pm HST
Bacterial wilt (BW) of tomatoes, caused by Ralstonia solanacearum, is a devastating dis-ease that results in large annual yield losses worldwide. Management of BW of toma-toes is difficult due to the soil-borne nature of the pathogen. One of the best ways to mitigate the losses is through breeding for disease resistance. Moreover, plant height (PH) is a crucial element related to plant architecture which determines nutrient management and mechanical harvesting in tomatoes. An intra-specific F2 segregating population (NC 11212) of tomatoes was developed by crossing NC 84173 (tall, BW susceptible) x CLN1466EA (short, BW resistant). We performed quantitative trait loci (QTL) mapping using single nucleotide polymorphic (SNP) markers and the NC 11212 F2 segregating population. The QTL analysis for BW resistance revealed a total of three QTLs on chromosomes 1, 2, and 3, explaining phenotypic variation (R2) ranging from 3.6% to 14.9%. Whereas, QTL analysis for PH also detected three QTLs on chromo-somes 1, 8, and 11 explaining R2 ranging from 7.1% to 11%. This work thus provides information to improve BW resistance and plant architecture-related traits in toma-toes.
Speakers Co-authors
DP

Dilip Panthee

North Carolina State University
ES

Emily Silverman

North Carolina State University
NA
MI

Muhammad Irfan Siddique

North Carolina State University
NA
Friday September 27, 2024 11:50am - 12:00pm HST
Coral 1

11:55am HST

PB - Efficient high molecular weight DNA isolation and whole genome sequencing of papaya for molecular applications
Friday September 27, 2024 11:55am - 12:05pm HST
Plant whole genome sequencing provides detailed information on gene content, genome organization, and evolutionary relationships as well as supports biotechnological applications such as gene editing. The first 3X draft genome sequence of papaya based on whole genome shotgun reads from the transgenic ‘SunUp’ papaya cultivar was published in 2008. Since then, advancements in sequencing and whole genome assembly enabled a near complete sequence of ‘SunUp’ and a detailed picture of events resulting from particle gun-mediated transformation. With current technology, the 372 Mb genome size of papaya makes it tractable for routine whole genome sequencing to characterize different cultivars and molecular events. In this study, we improved ease and speed of preparation, efficiency of recovery, and DNA quality through a combination of classical and contemporary plant nuclei or high molecular weight DNA isolation methods. Leveraging Hi-Fi sequencing and Hi-C technology, we achieved rapid chromosome-level sequence assembly of two local Hawaiian cultivars, Kapoho and Waimanalo. The assembled genomes of Kapoho and Waimanalo spanned 341.6 Mb and 337.4 Mb, respectively, with a total of 20,343 and 20,165 annotated protein-coding genes.
Speakers
JS

Jon Suzuki

USDA ARS DKI U.S. PBARC
Co-authors
BC

Briette Corpuz

USDA ARS US DKI PBARC
HL

Haomin Lyu

USDA ARS Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
QY

Qingyi Yu

USDA, ARS, Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
SG

Scott Geib

USDA-ARS
SS

Sheina Sim

USDA-ARS
Friday September 27, 2024 11:55am - 12:05pm HST
South Pacific 3

11:59am HST

Water Utilization and Management (WUM)
Friday September 27, 2024 11:59am - 12:30pm HST
Evaluating Saline Irrigation Management Strategies Under Drip Irrigated Pistachio - Mukesh Mehata
Lysimetric Determination of Crop Water Requirements for Sorghum - Florence Cassel
Evaluating the distribution uniformity of spray-stakes using pressure compensating emitters - Chris Shogren
Moderator
CS

Chris Shogren

UCCE Los Angeles
Friday September 27, 2024 11:59am - 12:30pm HST
Nautilus 1

11:59am HST

Commercial Horticulture 2 (CHEX 2)
Friday September 27, 2024 11:59am - 1:15pm HST
The Kentucky Small Fruits Initiative: An Extension-Industry Partnership - Cindy Finneseth
Case Study: Assessing Workforce Training Needs And UMKC Student Interest To Develop Controlled Environment Agriculture Education In Kansas City - Juan Cabrera Garcia
Assisting Florida Sod Producers with Protecting Water Quality by Quantifying Nutrient Inputs and Exports - Bonnie Wells
Will Consumers Purchase a Landscape Scouting Program? - Andrew Jeffers
Native Plant Extension Programming for Commercial Horticulture Professionals - William Errickson

Moderator
CF

Cindy Finneseth

Kentucky Horticulture Council
Friday September 27, 2024 11:59am - 1:15pm HST
South Pacific 2

11:59am HST

Human Issues in Horticulture (HIH)
Friday September 27, 2024 11:59am - 1:15pm HST
Therapeutic Horticulture and Chronic Lower Back Pain: A Pilot Study at the University of Florida - Elizabeth Diehl
Integrating Developmentally Disabled Individuals Into the Oklahoma Green Industry Workforce - Mike Schnelle
The Effect of a Plant Distribution and Care Program on First-Year University Student Retention, Levels of Depression, Stress, Anxiety, and Loneliness - Srinivas Reddy Adama
Evaluating the Needs and Barriers of Commercial Fruit and Vegetable Growers in Southwest Puerto Rico: A Qualitative Approach - Angela Linares Ramirez
Soilborne Disease, Plant-parasitic Nematode, Insect Pest, and Weed Challenges Faced by High Tunnel Growers and Preferred Strategies to Overcome Those Challenges: Preliminary Results from a Kentucky Farmer Survey - Margarita Velandia
Gauging 8th Graders’ Knowledge of Organic Agriculture Production and Labeling Practices - Christine Coker
Moderator
TW

Tina Waliczek Cade

Texas State University
Friday September 27, 2024 11:59am - 1:15pm HST
South Pacific 1

11:59am HST

Vegetable Breeding 3 (VGBR 3)
Friday September 27, 2024 11:59am - 2:00pm HST
Evaluation of Vegetable Soybean Breeding Lines for Yield and Related Traits - GuoLiang Jiang
Could Broccoli's Ancestral Lineage Hold the Key to Increased Fatty Acid Content? - Alaina Kleine
Characterization of A Novel Locus for Fruit Flavor Aroma in Tomato - Qian Feng
Identification and Validation of Novel Resistance Loci to Fusarium oxysporum f.sp. lycopersici Race 3 in Tomatoes - Samuel Ipinyomi
Enhancing Fusarium Wilt Race 2-Resistance and Brix Content in Watermelon through Genomic Selection - Anju Biswas
Introgressing QTL from a Wild Relative to Improve Gummy Stem Blight Resistance in Watermelon - Cecilia McGregor
Genome-wide association study reveals potential loci for powdery mildew resistance in the USDA core collection of Cucurbita pepo - Prerna Sabharwal
BreedwithBIMS (Breeding Information Management System) for Crop Breeders - Ksenija Gasic
Moderator
CM

Cecilia McGregor

University of Georgia
NA
Friday September 27, 2024 11:59am - 2:00pm HST
South Pacific 4

12:00pm HST

VGBR - Effects of Prolonged Photoperiod on Chile Pepper Plant Architecture and Growth Habit
Friday September 27, 2024 12:00pm - 12:10pm HST
This experiment sought to examine the effects of prolonged photoperiod and modified temperature and humidity in chile peppers, aiming to develop a protocol to accelerate their growth and enhance breeding efficiency. Four genotypes from three Capsicum species (C. annuum - Chimayo, Early Jalapeno; C. chinense - Orange Habanero; Chiltepin - C. annuum var. glabriusculum) were planted in two randomized flat trays per entry using SunGro propagation soil. After reaching the 2-3 leaf stage, they were transplanted into 8” pots, incorporating sterilized and LM-AP soil mixtures. The experimental population was grown in an improvised growth chamber with an average temperature of 25°C and humidity of 60% and exposed to a 20-hour daily cycle of 450 nm full spectrum LED grow lights and 730 nm Far Red LED grow lights and 4 hours of darkness. The control group grew in normal greenhouse conditions, exposed to normal daylight intensity and duration and an average temperature of 21°C and humidity of 40%. Weekly data recordings included plant growth measurements of plant height and leaf count. Basal branches were counted approximately 12 weeks after planting, and leaf widths were recorded 14 weeks after transplanting. Number of flowers and fruits were also recorded at 14 weeks after transplanting. Data were analyzed using RStudio, and Tukey HSD was used to detect differences between treatments and among genotypes. In terms of plant height, all experimental plants demonstrated a significant increase compared to the control group, both in absolute amounts and in rates, especially later in the growth stage. The leaf numbers in experimental plants were significantly lower than the control group, except for Orange Habanero, which showed no significant difference. Early Jalapeno, in both treatments, exhibited no significant difference in basal branches. In contrast, the remaining experimental plants displayed fewer or no basal branches compared to the control group. All experimental plants exhibited significantly wider leaves in comparison with the control group. While most experimental plants started flowering earlier, no significant differences were observed between numbers of flowers and fruits. The faster growth rates observed hold the promise of accelerated progress and improved efficiency in breeding initiatives, offering a fundamental shift in the way we approach crop development. Additionally, fewer number of basal branches may have implications for machine harvestability, as fewer basal branches is considered a desirable trait for machine harvesting.
Speakers
SN

Shahab Nourbakhsh

New Mexico State University
Co-authors
DN

Dennis Nicuh Lozada

New Mexico State University
IP

Isaac Porras

New Mexico State University
NA
RR

Rhiannon Rodriguez

New Mexico State University
NA
TT

Tyra Trumble

New Mexico State University
NA
Friday September 27, 2024 12:00pm - 12:10pm HST
Coral 1

12:00pm HST

WUM - Evaluating Saline Irrigation Management Strategies Under Drip Irrigated Pistachio
Friday September 27, 2024 12:00pm - 12:10pm HST
Over 85% of California's bearing pistachio acreage is located in soils with moderate (4 dS/m) to extremely high (16 dS/m) saline. Several previous studies have demonstrated that pistachios can be grown profitably even in moderately saline soils, with optimal soil salinity (ECe) maintained at approximately 4.5 - 6 dS/m. One common practice to reduce the salinity level in rootzone is to apply good quality water during dormant season. As the availability of good quality canal water for in-season irrigation and dormant season leaching declines, growers are relying more on semi-saline pumped groundwater, particularly in the San Joaquin Valley Westside. It would be beneficial to understand if the volume of dormant season leaching could be reduced, if in-season methods of leaching could be effective, and how to use moderately saline water most efficiently for both dormant and in-season leaching. Current methods for managing salinity through dormant leaching rely on one-dimensional models assuming complete surface wetting. We are exploring alternative approaches, investigating the effectiveness of single and double drip lines in managing root zone salinity using in-row, in-season leaching fractions and small volume pulsed dormant leaching. Preliminary results showed that generally, all leaching treatments, (in-season leaching, dormant leaching and the combination of both, applied with both single and double hose lines, significantly decreased soil ECe relative to the control, reducing ECe values of 13-22% relative to their respective controls. All the leaching treatments also effectively prevented boron from accumulating in the soil relative to the control. No clear effects of line configuration, double versus single line, were detected in soil levels. These findings indicate that treatments are effectively reducing salinity or at least preventing the increases observed in the control. Leaf analysis showed that in-season leaching, with/without dormant leaching, significantly increased leaf nitrogen and phosphorus, and reduced leaf boron accumulation.
Speakers
MM

Mukesh Mehata

University of California, Davis
Co-authors
BM

Blake Mccullough Sanden

University of California Davis
NA
CB

Clay Beck

Maricopa Orchard
NA
GM

Giulia Marino

University of California, Davis
NA
JC

Joseph Coehlo

Valley Orchard LLC
NA
LF

Louise Ferguson

University of California, Davis
NA
MC

Mae Culumber

University of California, Davis
NA
MS

Marta Saludes

Universidad de Salamanca
NA
Friday September 27, 2024 12:00pm - 12:10pm HST
Nautilus 1

12:00pm HST

CHEX 2 - The Kentucky Small Fruits Initiative: An Extension-Industry Partnership
Friday September 27, 2024 12:00pm - 12:15pm HST
Growers in Kentucky are increasingly interested in adding small fruit crop enterprises to their farming operations. While consumer demand is high, available capital and limited production knowledge are known barriers for small- and mid-scale producers interested in growing and selling these crops. The Kentucky Horticulture Council (KHC) and the University of Kentucky (UK) partnered on a financial and technical assistance support program for Kentucky growers with an interest in producing these crops. Over the 4-year project, more than $936,000 was invested in on-farm projects, working with 275 existing and 76 pre-commercial growers in 89 different counties across the state. Blackberry, blueberry, and strawberry were the highest demand crops. Irrigation, trellising, and netting were the most requested non-plant material inputs. The expected farm impact over the next 10 years will exceed $7.4M, based on yield and sales price estimates. The funding model providing financial assistance to current and prospective growers along with extension’s role in delivering research-based information and providing technical assistance will be discussed. The presentation will also focus on strategies to recruit and screen program participants by assessing needs, setting realistic expectations, increasing production knowledge and skills, with the goal of fostering satisfaction and meeting the intended project objective of increasing small fruit crops profitability for commercial sales over the next decade and beyond.
Speakers
CF

Cindy Finneseth

Kentucky Horticulture Council
Co-authors
DB

Daniel Becker

University of Kentucky
NA
DS

Delia Scott

University of Kentucky
NA
SW

Shawn Wright

University of Kentucky
NA
Friday September 27, 2024 12:00pm - 12:15pm HST
South Pacific 2

12:00pm HST

HIH - Therapeutic Horticulture and Chronic Lower Back Pain: A Pilot Study at the University of Florida
Friday September 27, 2024 12:00pm - 12:15pm HST
The specific aims of this pilot study were to 1) determine if and which patients, receiving care for chronic lower back pain (LBP) in the UF Health Comprehensive Spine Center, were interested in therapeutic horticulture to manage LBP, and 2) quantify changes in LBP, functional tasks, and anxiety upon completion of a therapeutic horticulture session. The study hypothesis was that individuals participating in the therapeutic horticulture intervention would demonstrate improvements in spine mobility and physical function as well as a reduction in spine pain severity from pre- to post-session. This was a two-part study with a mixed methods design including cross-sectional survey and pilot experimental components. Results revealed that 68% of patients were interested in learning about therapeutic horticulture for LBP. Among those patients who participated in the intervention, improvements were observed in anxiety, spine flexion, and spine rotation to the left.
Speakers
avatar for Elizabeth Diehl

Elizabeth Diehl

Director of Therapeutic Horticulture, University of Florida
The mission of the University of Florida’s Therapeutic Horticulture Program at Wilmot Botanical Gardens is to improve lives through engaging with plants and nature. The program is situated at the nexus of the gardens’ commitment to patient care, education, and research, drawing... Read More →
Friday September 27, 2024 12:00pm - 12:15pm HST
South Pacific 1

12:00pm HST

VGBR 3 - Evaluation of Vegetable Soybean Breeding Lines for Yield and Related Traits
Friday September 27, 2024 12:00pm - 12:15pm HST
Vegetable soybean (Glycine max), also known as edamame, is a specialty soybean that is harvested at R6 growth stage. Vegetable soybean has steadily increased in acreage and market demand although it is relatively new to North America. It is of significance to develop new cultivars that are more adapted to local environment and crop management system to promote specialty crop production and meet the market requirements. In this study, 14 genotypes of vegetable soybean, including 10 breeding lines and 4 check cultivars, were evaluated during 2020-2023 for potential uses as edamame. There were significant differences among genotypes in both fresh pod and mature seed yields, agronomic and seed composition traits investigated. The year effects and genotype x year interactions were also significant in most cases. Fresh pod yield averaged 11,227.5 kg ha-1, ranging 9,800.1 – 13,154.3 kg ha-1, and mature seed yield averaged 2,814.7 kg ha-1, ranging 2,029.2 – 3,175.2 kg ha-1. The average 100-seed weight of 14 genotypes was 26.9 g, ranging 23.1 – 30.1 g. Maturity averaged 153.3 days after planting, ranging 147.1 – 159.5 days. On a dry weight basis, seed protein, oil and sucrose contents averaged 43.5%, 18.7% and 5.0%, respectively. The estimates of broad-sense heritability were medium to high (66.82 – 94.90%) for most of the traits, while the heritability estimates for fresh pod yield and duration from flowering to maturity were relatively low (23.44% and 42.29%). Several breeding lines exhibited good yield, larger seed size, higher contents of protein, oil, oleic acid and sulfur-containing amino acids, suggesting the potential of release and commercial production.
Speakers
GJ

GuoLiang Jiang

Virginia State University
NA
Friday September 27, 2024 12:00pm - 12:15pm HST
South Pacific 4

12:00pm HST

VSF 5 - Effect of Temperature and Light during Cold Storage of Strawberry Liners
Friday September 27, 2024 12:00pm - 12:15pm HST
Identifying storage conditions for strawberry liners propagated in controlled environments is needed to enable mass production of plant material for field growers. The objective was to compare the effect of crown diameter (CD), light, and temperature during cold storage (CS) on growth and subsequent yield of ‘Albion’ strawberry liners propagated indoors for 4 weeks under 24 or 16 h·d–1 (experiments 1 and 2, respectively) using white light-emitting diode fixtures. After propagation, plants of two CD (small 10mm) were stored during 4 weeks under 24 temperatures (ranging from -2 to 7 C) and 47% relative humidity, with or without 5 μmol·m–2·s–1 of white light provided for 24 h·d–1. Plants were moved to a common greenhouse compartment after each CS experiment and grown for 8 weeks to evaluate carryover effects on fruit yield. Overall, shoot and root dry mass were lower in plants exposed to CS compared to the initial baseline material, indicating a general loss of biomass during CS, regardless of treatment. The use of light did not affect any of the parameters evaluated, indicating that liners can be stored under darkness. In experiment 1, plants with large CD had higher chlorophyll concentration than those with small CD, but the opposite trend was measured in experiment 2. As expected, plants with large CD had longer petioles and produced more shoots during CS than those with small CD, regardless of experiment. Plants stored under ≤ -1.4 or -1.9 °C for experiments 1 and 2, respectively, died during the carryover phase, suggesting that liners should not be stored at or below these low temperatures. However, no treatment differences were measured after the carryover phase for plants stored in all other treatments. Further results highlighting the effect of temperature during CS will be presented.
Speakers
LD

Lian Duron

Purdue University
Friday September 27, 2024 12:00pm - 12:15pm HST
Coral 3

12:00pm HST

Technical Program Committee
Friday September 27, 2024 12:00pm - 1:00pm HST
Moderator
KO

Kathryn Orvis

Professor, Purdue Univ
CS

Carl Sams

University of Tennessee
avatar for Sandra Wilson

Sandra Wilson

Professor, University of Florida
Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral... Read More →
Friday September 27, 2024 12:00pm - 1:00pm HST
Sea Pearl 3
  Meetings - Committee/Division/interest Group
  • about Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral studies at both Clemson University and Chiba University, Japan. Dr. Wilson teaches courses on Native Florida Landscaping, Plant Propagation, and Annual and Perennial Gardening. She has been recognized nationally with numerous awards for her scholarship in teaching and development of interactive online materials on plant propagation, plant family classification, greenhouse education, and bee-friendly gardening. Dr. Wilson’s research focuses on (1) propagation and evaluation of native plants and their pollinator attraction, and (2) characterizing the invasive potential of ornamental plants in Florida such as lantana, nandina, ligustrum, porterweed and Mexican petunia. She has co-authored over 150 scientific and technical articles in plant propagation, container production, and landscape use. In 2018, she has become the newest co-author of the 9th edition world standard textbook, Hartmann and Kester’s Plant Propagation: Principles and Practices. For her outstanding contributions to horticultural science and education, she holds the distinction of Fellow within International Plant Propagators Society (IPPS), American Society for Horticultural Science (ASHS), and the North American Colleges and Teaching of Agriculture (NACTA).

12:05pm HST

PB - Tissue Culture Regeneration of Miscanthus Sinensis ’Gracillimus’
Friday September 27, 2024 12:05pm - 12:15pm HST
The genus Miscanthus is considered an ideal choice for both ornamental and biofuel purposes, owing to its appealing aesthetics and significant potential for high-energy biomass production. Traditional breeding efforts in Miscanthus have predominantly focused on enhancing nutrient efficiency and tolerance to both biotic and abiotic stresses. However, these endeavors are often time-consuming. The emergence of plant genome editing technologies has opened up a new and efficient avenue for Miscanthus breeding. These innovative techniques hold promise for accelerating the breeding process, allowing for more rapid and targeted improvements in desired traits. The development of an efficient plant regeneration system is crucial for the application of modern genome editing technologies in Miscanthus breeding and for achieving large-scale biomass production. Among the Miscanthus species, Miscanthus sinensis poses a particular challenge in tissue culture regeneration. In this report, we present an effective system for callus induction and regeneration in Miscanthus sinensis. Callus was induced from the stems of in vitro-cultured Miscanthus sinensis 'Gracillimus' using a modified MS media supplemented with varying levels of 2,4-D. Regeneration-competent callus was achieved through continuous selection on the callus maintenance/selection medium over a period of 6 months. Remarkably, 100% of the callus successfully regenerated new shoots on a modified MS medium containing Benzylaminopurine (6-BA) and α-Naphthaleneacetic acid (NAA). This marks the first efficient 'Gracillimus' regeneration system using in vitro culture as the starting material. The established system demonstrates a high potential for the micropropagation of Miscanthus sinensis 'Gracillimus' with a propagation rate of 3.5. Currently, efforts are underway for genome editing of Miscanthus sinensis utilizing this established system.
Speakers
KD

Kedong Da

North Carolina State University
Director of plant transformation lab at North Carolina State University
Co-authors
AN

Anna Nelson

NC State University
NA
HL

Huani Leng

North Carolina State University
NA
JN

John Nix

NC State University
NA
KM

Keren Morales

North Carolina State University
NA
SM

Sydney McLennan

North Carolina State University
NA
TR

Thomas Ranny

North Carolina State University
NA
WL

Wusheng Liu

North Carolina State University
Friday September 27, 2024 12:05pm - 12:15pm HST
South Pacific 3

12:10pm HST

VGBR - Seasonal Lettuce Germplasm Trials in Northeast Florida Hydroponics
Friday September 27, 2024 12:10pm - 12:20pm HST
The Hastings Agricultural Extension Center adopted the lettuce variety trials in 2018 for the demonstration of alternative row crops. Within the Tri-County Agricultural Area (TCAA), the term "alternative" refers to any crops outside of the traditional rotations - potatoes and cabbage. While these crops are the staple of the community, the acreage has been reduced due to tight profit margins and competitiveness for chipping contracts. Lettuce, along with artichokes and pumpkins, have been one of the newly adopted commodities for North Florida. What initially began as field trials expanded into the controlled systems of protected agricultural and hydroponics. Three seasons of germplasm trials with 14 newly developed lines in the hydroponic towers were conducted in Hastings to evaluate their soilless potential. Under 20% shade, lettuce was grown in the Verti-Gro system with 40% perlite, 30% coconut coir and 30% peat moss. These trials were also home to many field tours for the community, and opportunities for local growers to witness and observe their growth habits. Data evaluations included marketability, timing (if observed) of bolting, tip burn, and head weights. Weights ranged from 0.10 - 0.85 kg, with Botrytis and Sclerotinia being the most common disease pest identified. Since the trials began, our lettuce acreage has increased from 15 to 100 in the county, including two organic growers and one conventional, and with opportunities for more research to benefit these diversified growers.
Speakers
EF

Evelyn Fletcher

University of Florida
I am the commercial row-crop Extension Agent for St. Johns County, FL.
Co-authors
GS

German Sandoya

University of Florida
Friday September 27, 2024 12:10pm - 12:20pm HST
Coral 1

12:10pm HST

WUM - Lysimetric Determination of Crop Water Requirements for Sorghum
Friday September 27, 2024 12:10pm - 12:20pm HST
Accurate estimation of crop water requirements (CWR) is essential to optimize water use efficiency and develop efficient irrigation scheduling practices. This is particularly important in California where frequent droughts have accentuated the need to conserve water and improve on-farm water management. The most accurate method to determine CWR is with precision weighing lysimeters, which measure actual crop evapotranspiration (ETa). Thus, the objectives of this study were to determine ETa data, develop new crop coefficients (Kc), and evaluate the relationship between Kc and crop fractional ground cover (Fc) for forage sorghum grown under drip irrigation. Being drought and salt tolerant, sorghum has been considered as an alternative crop to corn in regions of water scarcity and marginal soils. Daily ETa measurements were collected over three years on a clay loam soil using the precision weighing lysimeter available at the University of California Westside Research and Extension Center in Five Points, CA. Crop coefficient (Kc) estimates were derived from the ETa measurements and reference ETo data were obtained from a CIMIS weather station located at the study site. Weekly Fc measurements were also performed to derive relationships between Kc and fractional ground cover. Results from our study indicated that the seasonal ETc ranged from 665 to 870 mm, with average peak ET of 7.0 mm/day and midseason Kc spanning from 0.90 to 1.1. A strong correlation (r2 > 0.95) was also observed between crop Kc and Fc. This study represents the first experiment determining ETc and Kc for forage sorghum grown under drip irrigation in California. Findings also demonstrated the variability of CWR due to seasonal differences.
Speakers
FC

Florence Cassel

California State University, Fresno
Co-authors
DG

Dave Goorahoo

California State University, Fresno
NA
IN

Idalia Navarro

California State University, Fresno
NA
RS

Rafael Solorio

California State University, Fresno
NA
SA

Shawn Ashkan

California State University, Fresno
NA
Friday September 27, 2024 12:10pm - 12:20pm HST
Nautilus 1

12:14pm HST

Ornamentals/Landscape and Turf 2 (O/LT 2)
Friday September 27, 2024 12:14pm - 1:25pm HST
Impact of Lawn Age on Soil Organic Matter, Microbial Respiration, and Nitrogen Mineralization - Alex Lindsey
Effect of Organic Fertilizers and Biostimulants on ‘TifEagle’ Bermudagrass Greens - Marco Schiavon
Detection of QTL Associated with Morphological, Adaptive, and Reproductive Traits in Common Bermudagrass - Shuhao Yu
Alternate Products to Control Silvery Thread Moss in a Creeping Bentgrass Putting Green - Shehbaz Singh
Evaluation of Gypsum and Fertilizers for Enhanced Bermudagrass Performance Under Salinity Conditions in Florida Sandy Soils - Idalia Sierra
Cold-hardiness, Flowering, and Disease Resistance of 24 Camellia Cultivars and Selections in Tennessee, USA - Jacob Shreckhise
The American Rose Trials for Sustainability® (A.R.T.S.®) Program Announces Five Winning Roses for 2025 - Kristine Lang

Moderator
SY

Shuhao Yu

Oklahoma State University
Friday September 27, 2024 12:14pm - 1:25pm HST
Coral 2

12:14pm HST

Postharvest 3 (PH 3)
Friday September 27, 2024 12:14pm - 1:35pm HST
Evaluating the Potential of Gaseous Ozone to Suppress Decay Incidence in Fresh Peaches During Cold Storage - Orestis Giannopoulos
Evaluation of different reflectance models to predict fruit firmness using compression values in sweet cherries cv ‘Skeena’ - Rene Mogollon
Effects of Harvest Regimes on Shelf-life and Quality of Rabbiteye Blueberries - Amit Godara
Facilitating Postharvest Elderberry Fruit Detachment with Ethylene - Steven Sargent
Integrated Analyses of Transcriptomics and Lipidomics Reveal Potential Mechanisms Related to Physiological Disorders of Cold-Stored Hardy Kiwifruit (Actinidia arguta) - Hyowon Park
β-Cyclodextrin Nano-encapsulated Carvacrol Inclusion Complexes Improve Postharvest Quality of Limes - Chang Shu
Nondestructive Detection of Chilling Injury Based on VIS/NIR Spectroscopy in Sweet Potato - Jonghwan Lee
Development and Characterization of Bio-based Nanoparticle Coatings from Sweetpotato Peels - David Picha

Moderator
CS

Chang Shu

USDA-Agricultural Research Service-Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
Friday September 27, 2024 12:14pm - 1:35pm HST
Lehua Suite

12:14pm HST

Citrus Crops (CITR)
Friday September 27, 2024 12:14pm - 1:55pm HST
Encouraging Homeowner Citrus in Florida - David Austin
Effect of Molybdenum Fertilization on Young Huanglongbing-Affected Citrus Trees - Kondwani Kamsikiri
Investigating the Impact of Macronutrient Management on Performance of Huanglongbing (HLB)-Affected Sweet Oranges- Monkia Peddapuli
Modifications in Existing Nitrogen Recommendations for HLB-Affected Sweet Orange Trees in Florida - Noor Ul Basar
Evaluating the Impact of Fabric Mulch Ground Cover on Grapefruit Tree Growth and Soil Characteristics in the Indian River Region of Florida - Audrey Beany
High-throughput Phenotyping and Fruit Juice Quality of 'OLL-8' Sweet Orange Scion on Different Rootstocks with Comparison of Oxytetracycline Injections - Emily Worbington
Assessing Tree and Root Responses of Various HLB-affected Citrus Cultivars Using Oxytetracycline Trunk Injections - Giancarlo Buzzi
Assessment of Biomass and Carbon Storage of Satsuma Mandarin Trees in Jeju Island, Korea - Jeesoo Park
Effect of Gamma Irradiation on Survival, Fruit Characteristic, and Thorn Length in Different Varieties of Citrus - Dong Hoon Lee
Insights from a Citrus Breeding Program: Leveraging the Citrus Genome Database and Breeding Information Management System - Ronald Tapia





Friday September 27, 2024 12:14pm - 1:55pm HST
Kahili

12:15pm HST

CITR - Encouraging Homeowner Citrus in Florida
Friday September 27, 2024 12:15pm - 12:25pm HST
Background: Florida’s Citrus industry has been devastated by the bacterial disease, Huanglongbing (HLB) (Candidatus Liberibacter asiaticus). The vector of the disease is the Asian Citrus Psyllid (Diaphorina citri). HLB is not just a problem in Florida but affects other citrus-growing areas across the United States. Many homeowner citrus trees already have HLB or have succumbed to the disease. Often, young trees are purchased and decline before they have harvestable fruit. Many homeowners, not educated on the disease, have become disenchanted with attempting to grow citrus. Although no citrus is resistant to HLB, there are tolerant varieties. Objective: Engage Highlands County residents to grow citrus in their yards by offering classes on the proper use of cultural practices to successfully maintain a tree that would supply quality fruit for a longer duration. Introduce them to HLB-tolerant trees and other innovations. Method: Lecture using a two-hour PowerPoint on growing citrus. Teach participants how to identify HLB and other common citrus pests and diseases. Give them a better understanding of citrus nutrition, soil health, and irrigation practices. Introduce them to Individual Protective Covers (IPCs) that can exclude Asian Citrus Psyllids from reaching their trees. Send them home with the knowledge to grow successful citrus at home. Conclusion: In 2023 and 2024, 112 participants attended the Growing Citrus at Home program. Of this, 92 trees were taken home each with an IPC. Seventy-five class participants took a pre- and post-assessment to ascertain knowledge gain. Knowledge gain based on a 10-question pre-and post-assessment went from 36% to 68% which calculates to be an increase of 89 %. pests and diseases. Give them a better understanding of citrus nutrition, soil health, and irrigation practices. Introduce them to Individual Protective Covers (IPCs) that can exclude Asian Citrus Psyllids from reaching their trees. Send them home with the knowledge to grow successful citrus at home. Conclusion: In 2023 and 2024 112 participants attended the Growing Citrus at Home program.
Speakers
avatar for David Austin

David Austin

UFIFAS
David Austin is a Residential Horticulture Agent for UF/IFAS Extension, Highlands County, and their Master Gardener Volunteer Coordinator. He has a Bachelor of Science in Horticulture from the University of Florida in 1984 and is presently working on his Masters in Landscape Pest... Read More →
Friday September 27, 2024 12:15pm - 12:25pm HST
Kahili

12:15pm HST

O/LT 2 - Impact of Lawn Age on Soil Organic Matter, Microbial Respiration, and Nitrogen Mineralization
Friday September 27, 2024 12:15pm - 12:25pm HST
Aesthetically appealing and ecosystem servicing turfgrass lawns require proper nutrition and adequate water, which are generally provided by fertilization and supplemental irrigation. However, mismanaged fertilizer and irrigation practices can lead to nutrient losses to the environment, especially nitrogen (N). Model simulations suggest that as the age of the turf stand increases it may be possible to reduce N fertilization and still maintain acceptable turf quality. This is likely due to increases in soil organic matter with turf maturation, which has the potential to provide plant-available N. However, little research has been performed on carbon (C) sequestration and N mineralization in urban residential soils in Florida. It is hypothesized that as lawn age increases it will result in greater C sequestration, microbial activity, and N mineralization. This study was conducted at Lakewood Ranch, FL. Soil samples were collected from lawns with the following ages: 1, 3, 5, 10, 15, and 20 years old. The soil samples were sieved, homogenized, and air-dried prior to soil analysis. Soil analysis included soil organic matter (loss-on-ignition), microbial activity (potentially mineralizable C), and N mineralization (potentially mineralizable N). Data was subjected to analysis of variance (ANOVA) and treatment mean comparisons were separated using Fisher's least significant difference (LSD) at the p ≤ 0.05 level. Lawn age had an impact on soil organic matter, microbial activity, and N mineralization. In general, as a lawn ages, especially after 5 years, it increases the soil organic matter, microbial respiration, and N mineralization. This is the first-year data and a second year with multiple locations will be evaluated to confirm results. Future studies will involve optimizing fertilizer and irrigation recommendations for lawns of various ages.
Speakers
AL

AJ Lindsey

University of Florida
Friday September 27, 2024 12:15pm - 12:25pm HST
Coral 2

12:15pm HST

PB - In Vitro Shoot Regeneration Protocol For Southern Highbush Blueberry (SHB) Cultivars.
Friday September 27, 2024 12:15pm - 12:25pm HST
Blueberry (Vaccinium sp. L.) is one of the most important fruit crops from the Ericaceae family and the highbush blueberry (Vaccinium corymbosum) is the most widely grown species. It's popularity is increasing day-by-day because of their unique flavor and rich nutritional content. Consequently, significant efforts have been made to develop superior cultivars with high yield, biotic and abiotic stress resistance using conventional breeding. However, due to high heterozygosity, polyploidy and long juvenile period, traditional breeding approaches can often be tedious and time consuming. Therefore, there is need to integrate modern precision breeding tools with traditional ones, to accelerate blueberry crop improvement. However, the success of novel biotechnological tools like gene editing and conventional transformation relies on successful shoot regeneration system. Many studies in blueberry show a lack of reliable regeneration protocols and their genotype-dependency. Furthermore, most of the reported regeneration studies have been conducted on northern highbush blueberry (NHB) cultivars. Therefore, the current study aims to develop shoot regeneration protocol for seven important southern highbush blueberry (SHB) cultivars (Colossus, Optimus, Albus, Arcadia, Keecrsip, FL 14-242
Speakers
AK

Anandi Karn

University of Florida
Friday September 27, 2024 12:15pm - 12:25pm HST
South Pacific 3

12:15pm HST

PH 3 - Evaluating the Potential of Gaseous Ozone to Suppress Decay Incidence in Fresh Peaches During Cold Storage
Friday September 27, 2024 12:15pm - 12:25pm HST
Sanitizing fruit and vegetables with gaseous ozone promotes food safety, marketability, and extended postharvest shelf-life. Ozone is a self-decomposing gas that disinfects and neutralizes microorganisms on packing equipment, water, and produce surfaces. The USDA permits ozone use in "organic" products. Ozone is produced on-site through a corona discharge mechanism using commercially gaseous ozone generators. This study studied gaseous ozone application on peaches, ranging from 0.5 - 5 ppm compared to control storage (CS). Gaseous ozone applications are known for postharvest spoilage vulnerability to assess microbial load reduction and defense against diseases like brown rot and gray mold. Investigated varieties (July Prince, Scarlet Prince, August Lady, and O’Henry), stored under controlled conditions of 35°F (1.7°C) at 90% relative humidity, revealed that 5 ppm ozone resulted in high decay (~40-42%). However, 0.5 ppm treatment maintained peach quality comparable to controls, with decay rates between 3.5 to 7%. Notably, peaches treated with 0.5 ppm also exhibited higher firmness than the other treatments and unaffected visual quality up to the 28th storage day. The findings suggest ozone’s potential to enhance postharvest practices, highlighting its efficiency, and could serve as an effective counteract treatment for decay incidence that will benefit the peach industry.
Speakers
avatar for Orestis Giannopoulos

Orestis Giannopoulos

University of Georgia
Co-authors
AD

Angelos Deltsidis

University of Georgia
CE

Camille Esmel McAvoy

University of Georgia
NA
DC

Dario Chavez

University of Georgia
NA
RC

Ramsey Corn

University of Georgia
Friday September 27, 2024 12:15pm - 12:25pm HST
Lehua Suite

12:15pm HST

CHEX 2 - Case Study: Assessing Workforce Training Needs And UMKC Student Interest To Develop Controlled Environment Agriculture Education In Kansas City
Friday September 27, 2024 12:15pm - 12:30pm HST
Controlled environment agriculture (CEA) integrates technology to optimize crop performance. The project goal was to inform the development of CEA curriculum by understanding CEA workforce training needs and gauging student interest at the University of Missouri – Kansas City (UMKC). CEA industry surveys determined the knowledge/skills needed for employment and educational expectations. A second survey was sent to UMKC students to gauge their knowledge of/interest in a CEA educational program. The top five positions in demand by the CEA industry were: (1) manager, (2) worker, (3) research
Speakers
JC

Juan Cabrera Garcia

University of Missouri
Co-authors
AC

Angela Cottrell

University of Missouri - Kansas City
NA
CM

Caroline Matz

University of Missouri - Kansas City
NA
KC

Karin Chang

University of Missouri - Kansas City
NA
Friday September 27, 2024 12:15pm - 12:30pm HST
South Pacific 2

12:15pm HST

HIH - Integrating Developmentally Disabled Individuals Into the Oklahoma Green Industry Workforce
Friday September 27, 2024 12:15pm - 12:30pm HST
Horticulturists throughout the State of Oklahoma have a long history of interacting, mentoring, and often employing individuals with developmental disabilities. Young adults seeking vocational training in western Oklahoma have access to the Center of Family Love, Okarche, OK, whereas individuals and their families enjoy similar training opportunities in eastern Oklahoma utilizing services and programs offered by A New Leaf, Tulsa, OK metropolitan area. While not an exhaustive list of Oklahoma organizations that offer horticultural therapy and employment opportunities for the developmentally disabled, the two aforementioned businesses have a multidecade track record of successfully matching individuals' talents and skills with specific horticultural-type employment. Not only do clients/workers have opportunities to learn more about growing and marketing both ornamental and edible crops, but they also earn wages while being mainstreamed with the “growing public”. An overview of the genesis of these operations and how they have evolved over time will be highlighted. Lastly, examples will be outlined regarding how workers provide a learning opportunity for their clientele (consumers). Specifically, the public is exposed to and thus recognizes often overlooked value in people that have been wrongfully labeled and assumed not capable of commercial horticultural work activities/tasks, successful interaction with the public, and ultimately the ability to often acquire independent living skills.
Speakers
MS

Mike Schnelle

Oklahoma State University
Friday September 27, 2024 12:15pm - 12:30pm HST
South Pacific 1

12:15pm HST

VGBR 3 - Could Broccoli's Ancestral Lineage Hold the Key to Increased Fatty Acid Content?
Friday September 27, 2024 12:15pm - 12:30pm HST
In the pursuit of agricultural productivity, generations of breeding have often prioritized yield-related traits, inadvertently leading to the loss of desirable genetic traits linked to nutritional content. This phenomenon, known as the genetic lag effect, has implications for human health, particularly concerning the availability of essential nutrients such as omega-3 fatty acids. As omega-3 fatty acids are crucial for various aspects of human health, including heart health, cognitive function, and hormone regulation, it is imperative to explore alternative sources beyond traditional fish-derived options. The demand for plant-based alternatives is rising due to dietary preferences and concerns over fish oil production, emphasizing the need to investigate alternative sources of omega-3 fatty acids. Broccoli, with its rising consumption and rich nutritional profile, presents a promising avenue for addressing this need. For humans, the ideal ratio of omega 6 to omega 3, is 1:1. Yet, the American diet offers an astonishing 30:1 ratio! Broccoli has a ratio of 1:3 ratio. This is comparable to fish ranging from 1:1 to 1:7. Despite its potential, most broccoli breeding programs have focused primarily on grower-oriented traits rather than those beneficial to human health. Thus, there is an opportunity to enhance the nutritional content of broccoli, particularly its omega-3 fatty acid profile, to offer greater health benefits to consumers. This study investigates the omega-3 fatty acid profiles of 35 lines, 9 elite and 26 landrace broccoli cultivars, to address the pressing need for nutrient-rich foods. Our research employs lipid extraction from various tissues of broccoli plants, including bouquets, stems, and leaves. The lipid sample is screened using Gas Chromatography-Mass Spectrometry (GC-MS) for precise quantification and identification of fatty acids. Preliminary results reveal significant variation in omega-3 fatty acid content, specifically levels of alpha-linolenic acid (ALA) among the broccoli lines studied, highlighting the potential for breeding programs to select and develop varieties with enhanced nutritional profiles. By prioritizing consumer-oriented traits in crop breeding, such as omega-3 fatty acid content, we aim to contribute to developing biofortified broccoli varieties that offer sustainable and health-promoting dietary options. This research underscores the importance of diversifying food sources and prioritizing human health outcomes in agricultural practices to address evolving dietary needs and promote overall well-being.
Speakers
AK

Alaina Kleine

University of Florida
NA
Co-authors
AR

Andres Reyes Salinas

University of Florida
NA
CD

Carlos D Messina

University of Florida
NA
KB

Kelly Balmant

University of Florida
NA
MC

Melanie Cabrera

University of Florida
NA
Friday September 27, 2024 12:15pm - 12:30pm HST
South Pacific 4

12:20pm HST

VGBR - Marker Development for Cadmium for Accumulation in Spinach
Friday September 27, 2024 12:20pm - 12:30pm HST
California is the largest spinach producing state in the USA, accounting for 75% of hectares planted. The major production area is the Salinas Valley, which is known to have geogenic cadmium soils. Spinach is a hyperaccumulator and its affinity for divalent cations, like zinc and iron, likely contributes to the accumulation of Cd. Cadmium has known adverse health effects in humans, so California’s Office of Environmental Health Hazard Assessment’s (OEHHA) set a limit of 4.1 ug Cd per day by consumption. Consequently, growers do not produce spinach on high cadmium soils, limiting their ability to rotate crops throughout the valley. Even so, a few fresh leaf market spinach samples with foliar concentrations of Cd above the limit have been reported.

Our long-range objective is to develop improved fresh market spinach germplasm that restricts Cd uptake while maintaining nutritional quality. We have observed phenotypic variation for foliar cadmium concentration in a wide diversity of spinach germplasm with over 500 accessions originating from 42 countries, showed that greenhouse evaluations in high Cd soil largely reflected phenotypic performance in the field, and developed populations segregating for Cd uptake. We have also developed a hydroponic system that reflects field and greenhouse Cd uptake, but that is more controlled and scalable. Our current objectives are to identify quantitative trait loci (QTL) in the spinach genome associated with Cd accumulation. We have developed a biparental mapping population for genetic mapping by crossing high and low individuals which was evaluated in hydroponics earlier this year and will be evaluated in field conditions this fall. Markers tagging major QTL loci will be developed into high-throughput KASP markers for routine use in breeding.

Speakers
DF

Danyelle Forte

Graduate Student First Year, University of California - UC Davis
Co-authors
AV

Allen Van Deynze

University of California Davis
AK

Allison Krill-Brown

University of California Davis
DP

Daniel Pap

University of California Davis
EC

E. Charles Brummer

University of California Davis
MC

Marcia Carvalho

University of California Davis
RS

Richard Smith

University of California Davis
Friday September 27, 2024 12:20pm - 12:30pm HST
Coral 1

12:20pm HST

WUM - Evaluating the distribution uniformity of spray-stakes using pressure compensating emitters
Friday September 27, 2024 12:20pm - 12:30pm HST
Spray-stakes technology is common in nursery production systems, yet their distribution uniformity has been poorly studied. Recent innovations have the potential to increase distribution uniformity, but may be cost prohibitive. We analyzed the distribution uniformity of two brands of spray-stakes with and without pressure compensating emitters. We then conducted an economic analysis of switching from non-pressure compensating emitters to pressure compensating emitters. The average distribution uniformity measured was: 0.85 for non-pressure compensating Netafim Spray Stakes, 0.82 for the non-pressure compensating Primerus Spot Spitters, 0.95 for pressure compensating Netafim spray stakes, and 0.95 for pressure compensating Primerus Spot Spitters. While pressure compensating emitters do increase distribution uniformity, it would take 4-6 years based on water savings for the investment in pressure compensating emitters to break even, based on Southern California water prices.
Speakers
CS

Chris Shogren

UCCE Los Angeles
Co-authors
GS

Gerry Spinelli

University of California Cooperative Extension
Friday September 27, 2024 12:20pm - 12:30pm HST
Nautilus 1

12:25pm HST

CITR - Effect of Molybdenum Fertilization on Young Huanglongbing-Affected Citrus Trees
Friday September 27, 2024 12:25pm - 12:35pm HST
Optimal nutrient management improves the performance of citrus trees affected by Huanglongbing (HLB) in Florida. Current research suggests that HLB-affected trees may require higher levels of micronutrients than those typically recommended for citrus production to achieve optimum nutrition. However, application rates of some micronutrients like Molybdenum (Mo) remain unknown. Therefore, a study is being conducted at UF/IFAS Citrus Research
Speakers
KK

Kondwani Kamsikiri

University of Florida
Co-authors
DK

Davie Kadyampakeni

University of Florida
NA
Friday September 27, 2024 12:25pm - 12:35pm HST
Kahili

12:25pm HST

O/LT 2 - Effect of Organic Fertilizers and Biostimulants on ‘TifEagle’ Bermudagrass Greens
Friday September 27, 2024 12:25pm - 12:35pm HST
Turfgrass areas and golf industry have been under scrutiny for their potential impact on the environment, but more environmentally friendly organic fertilizers are increasingly being used to reduce and replace some inorganic fertilizers. A study was conducted on an 8-year-old ‘Tifeagle’ ultradwarf bermudagrass green mowed daily at 0.125 in. located at the University of Florida’s Fort Lauderdale Research and Education Center, Davie, FL to evaluate the effect organic fertilizers and biostimulants on turfgrass performance of Tifeagle’ bermudagrass green. Treatments included: a) XP Stress Rx (applied at 6 6 fl oz./1000 sq. ft.); b) XP-N Stress Rx (applied at 6 6 fl oz./1000 sq. ft.); XP-N Stress Rx Nautilus NuRelease (applied at 6 6 6 0.35 fl oz./1000 sq. ft.). Initial treatment was applied on June 1, 2023, with subsequent applications every 14 days for a total of nine applications. Data was collected every two weeks until three weeks after final application. Turf quality was measured on a 1-9 scale with 9=dark green dense turf, 1=dead/brown turf, and 6=minimally acceptable turf; Normalized Difference Vegetation Index (NDVI) was assessed using a RapidSCAN CS-45; percent green cover and Dark Green Color Index (DGCI) were assessed through Digital Image Analysis of one image taken per plot; volumetric water content was measured at a 3-inch depth using a time domain reflectance sensor. During the summer turfgrass quality, NDVI and DGCI were affected by treatment applications during five of the rating days. Overall, turfgrass fertilized with XP Stress Rx, XP-N Stress Rx and XP-N Stress Rx Nautilus NuRelease showed a higher quality, NDVI and DGCI compared to the unfertilized. Volumetric water content was affected by treatments only after the first application, and no differences were found thereafter. When temperature dropped, and up to three months after last application, biostimulants had a tremendous effect on ultradwarf bermudagrass health preventing the grass from Curvularia spp. infection and helping turfgrass maintaining quality and functionality through the winter.
Speakers
MS

Marco Schiavon

University of Florida
Co-authors
AS

Alejandra Sierra

University of Florida
Friday September 27, 2024 12:25pm - 12:35pm HST
Coral 2

12:25pm HST

PH 3 - Evaluation of different reflectance models to predict fruit firmness using compression values in sweet cherries cv ‘S
Friday September 27, 2024 12:25pm - 12:35pm HST
The compression test is the standard procedure to measure fruit firmness in sweet cherries. Nevertheless, this measurement is not always well correlated with perceived texture by buyers and consumers; therefore, the cherry industry needs a better way to grade fruit firmness. Hyperspectral information was correlated to fruit firmness as an alternative to compression values. ‘Skeena’ cherries, grown under commercial conditions in central Washington, were harvested in 2023 and stored for 30 days at 0-1oC. Compression measurements (at 20oC; FirmTech 2, BioWorks Inc) were carried out at harvest and 15 and 30 days into storage. Immediately after these measurements, hyperspectral images from the fruit (n=1030) were taken using a Vi-NIR camera (Headwall Photonics). The comparison between low (< 303 mm/g), medium (303-374 mm/g), and high firmness (>374 mm/g) groups did not yield any spectral differences. Despite this, iPLS wavelength selection showed bands > 800 nm suitable to model these compression groups. On the other hand, Neural Network, Random Forest, and PLS models were not able to predict compression values (regression) or firmness groups (classification). Furthermore, the regression models tested did not have coefficients of determination higher than 0.42 with root mean squared errors of 40 mm/g for compression values with the training dataset. Classification models achieved total accuracies of around 65-70 % and had problems distinguishing between low-medium and medium-high compression values. All models showed poor performance when tested with an independent data set. These results are in contrast to previous reports, which used a lower fruit number, reinforcing the challenge of tailoring a non-destructive technique to predict firmness through compression values in sweet cherries, a highly variable phenotypic characteristic.
Speakers
RM

Rene Mogollon

Washington State University
Co-authors
CT

Carolina Torres

Washington State University
Friday September 27, 2024 12:25pm - 12:35pm HST
Lehua Suite

12:30pm HST

CHEX 2 - Assisting Florida Sod Producers with Protecting Water Quality by Quantifying Nutrient Inputs and Exports
Friday September 27, 2024 12:30pm - 12:45pm HST
Adherence to the Florida Department of Agriculture's (FDACS) Best Management Practices (BMP) program is crucial for sod producers to protect water quality. Challenges arise due to perceived low fertilization rates and accelerated production cycles, particularly in South Florida. Challenges are exacerbated by the nutrient export that occurs when harvested sod carries away soil-bound nutrients and residual fertilizer. The sod BMP manual is undergoing revision, with a proposed emphasis on achieving a nutrient balance of nitrogen (N) and phosphorus (P) inputs/exports in sod operations. However, current published data on nutrient export needs to be more comprehensive, necessitating research efforts to fill this knowledge gap. This project, funded by a 2022-2023 FDACS BMP grant, aims to educate and improve sod producer BMPs by assessing current practices and quantifying nutrient inputs/exports through sod slab analysis. A Qualtrics survey was designed to measure sod producers' current BMP practices. Visits to sod farms were employed to collect sod slab samples for nutrient inputs/exports data processing. Results, particularly regarding N and P export, revealed variability across turfgrass species, highlighting the need for further research to determine nutrient sinks and explore the influence of soil depth on nutrient export during harvest. The project's future focus involves providing targeted training based on results to Florida sod producers and exploring additional funding opportunities to address remaining key questions. Results of this project will improve nutrient management inputs/exports budgeting by sod producers and facilitate adoption of practices that improve nutrient management for sod production statewide.
Speakers
BW

Bonnie Wells

University of Florida IFAS Extension
Dr. Bonnie Wells is the Commercial Horticulture Agent for the University of Florida IFAS Extension in Brevard County where she specializes in turfgrass and ornamental production and sustainable landscape maintenance. She is a Doctor of Plant Medicine (UF ’13) with more than 15 years... Read More →
Co-authors
AL

Alex Lindsey

University of Florida
BU

Bryan Unruh

University of Florida
NA
KK

Kevin Kenworthy

University of Florida
NA
MS

Marco Schiavon

University of Florida
MT

Mark Tancig

University of Florida IFAS Extension
NA
MV

Matthew VanWeelden

University of Florida IFAS Extension
NA
Friday September 27, 2024 12:30pm - 12:45pm HST
South Pacific 2

12:30pm HST

HIH - The Effect of a Plant Distribution and Care Program on First-Year University Student Retention, Levels of Depression, Stress, Anxiety, and Loneliness
Friday September 27, 2024 12:30pm - 12:45pm HST
The retention and recruitment of freshmen students transitioning to higher education or transferring to new institutions represent significant challenges for universities nationwide. Research underscores the mental health challenges encountered by students upon entering higher education, highlighting the necessity for effective resolution strategies. This study aimed to assess the impact of a plant distribution and care program on first-year university student retention, as well as levels of depression, stress, anxiety, and loneliness. The study employed a treatment and control group, both of which underwent pretest and posttest assessments using the DASS-21 and UCLA Loneliness scale, along with demographic information and prior experiences with mental health issues and plants. Recruitment for both groups was conducted through convenience sampling across university students. The treatment group participated in an 8-week program where they received designated plants and were instructed to care for them within their dormitories using plant care tips provided through an online platform. Additionally, they engaged in greenhouse activities. Conversely, the control group underwent pretest and posttest assessments at the same intervals as the treatment group, without any intervention. Results revealed a significant improvement in mental health among participants in the treatment group, despite data collection coinciding with final semester exams. Conversely, the control group exhibited no discernible differences between pretest and posttest assessments. These findings suggest that houseplants may serve as a viable means to mitigate stress, depression, anxiety, and loneliness among incoming university students.
Speakers
avatar for Srinivas Reddy Adama

Srinivas Reddy Adama

Graduate Instructional Assistant, Texas State University
Co-authors
TW

Tina Waliczek Cade

Texas State University
Friday September 27, 2024 12:30pm - 12:45pm HST
South Pacific 1

12:30pm HST

VGBR 3 - Characterization of A Novel Locus for Fruit Flavor Aroma in Tomato
Friday September 27, 2024 12:30pm - 12:45pm HST
Tomato flavor has become an important trait for targeted crop improvement. Because of the historical emphasis on yield and other agronomically important traits, many modern tomato varieties have lost their rich flavor, leading to consumer dissatisfaction. While volatile compounds play an important role in defining the distinct tomato flavor, little is known about their biochemical pathways, making it difficult to build a desirable volatile profile. Identifying the genes involved in volatile production can help us better understand the biochemistry as well as accelerate the breeding process. This study focuses on two consumer-desired volatiles, 1-nitro-2-phenylethane and phenylacetaldehyde, and has mapped a novel QTL on chromosome 8 by combining results from linkage mapping and GWAS (genome-wide association study). A cluster of Amino Acid Decarboxylases (AADCs) were identified as the candidate genes underlying this QTL and a total of four SV haplotypes of the AADC cluster were found in the Varitome collection. Among these haplotypes, Type III was lost during domestication and is a likely beneficial allele to increase the concentrations of phenylacetaldehyde and 1-nitro-2-phenylethane in tomato fruits. Preliminary data of transgenic plants created by CRISPR/Cas9 suggested a positive involvement of this AADC locus in volatile production. Enzymatic analysis of the AADC proteins and incorporation of the beneficial allele into modern tomato varieties is in progress. The outcome of this study will provide breeders valuable tools to facilitate the selection process for better tomato flavor. Characterization of volatile pathways will also give us insights on plant secondary metabolite biosynthesis and the evolution history during adaption and domestication. This research is funded by NSF IOS 2151032.
Speakers
QF

Qian Feng

Institute of Plant Breeding, Genetics and Genomics, University of Georgia
NA
Co-authors
AH

Austin Hart

University of Georgia
DT

Denise Tieman

University of Florida
EV

Esther van der Knaap

Institute of Plant Breeding, Genetics, and Genomics, University of Georgia
NA
LP

Lara Pereira

Center for Applied Genetic Technology, University of Georgia
NA
MS

Manoj Sapkota

University of Georgia
NA
WD

William Dobson

University of Florida
NA
Friday September 27, 2024 12:30pm - 12:45pm HST
South Pacific 4

12:35pm HST

CITR - Investigating the Impact of Macronutrient Management on Performance of Huanglongbing (HLB)-Affected Sweet Oranges.
Friday September 27, 2024 12:35pm - 12:45pm HST
Concerns about eutrophication that causes blooms of blue-green algae have strengthened over the last several decades due to the excessive use of pesticides and fertilizers, particularly those containing nitrogen (N) and phosphorus (P). These substances leached from agricultural fields and citrus groves into groundwater sources. Consequently, researchers developed best management practices (BMP) which are now being used to safeguard the environment while raising agricultural productivity. Additionally, Florida citrus production has decreased by more than 70% due to huanglongbing (HLB). Macro and micronutrient uptake is constrained owing to the decreased fibrous root density which may inflict root loss of up to 80%, depending on the severity of HLB-affected trees. The standard recommended rates of N and P were developed before the incidence of HLB and are no longer valid and warrant further refinement. Therefore, new site-specific guidelines are needed for the present situation. A study was started on 11-year-old ‘Valencia’ sweet orange trees (Citrus sinensis (L.) Osbeck) on Swingle citrumelo (Citrus paradisi Macf. × Poncirus trifoliata L. Raf.) rootstock in central Florida on Candler fine sand in 2023 to evaluate the impact of N and P fertilization on the growth and yield of HLB-affected citrus trees as well as to determine the optimal N and P rates for HLB-affected citrus trees in Florida. Eight treatments will be used over three years, with two N rates (112 and 224 kg/ha) as main plots and four P rates (0, 8.9, 17.8, and 35.7 kg/ha) as subplots in a factorial randomized complete block design. Tree height, canopy size, trunk diameter, fruit output, and juice quality are among the variables that will be measured. We anticipate that treatments that receive additional fertilization over the current recommendation have a significant chance of enhancing citrus growth and production. Keywords: Best management practices (BMP), Citrus sinensis, Huanglongbing, Site-specific nutrient management.
Speakers
MP

Monika Peddapuli

UNIVERSITY OF FLORIDA
Co-authors
AA

Alisheikh Atta

UNIVERSITY OF FLORIDA
Alisheikh Atta currently works at the Department of Soil, Water, and Ecosystem Science, University of Florida. Alisheikh does research on HLB-affected citrus nutrient and water management. He studies the impact of plant nutrients on the performance of citrus trees, irrigation water... Read More →
DK

Davie Kadyampakeni

UNIVERSITY OF FLORIDA
NA
Friday September 27, 2024 12:35pm - 12:45pm HST
Kahili

12:35pm HST

O/LT 2 - Detection of QTL Associated with Morphological, Adaptive, and Reproductive Traits in Common Bermudagrass
Friday September 27, 2024 12:35pm - 12:45pm HST
Cynodon dactylon (L.) Pers. is frequently used as turf and to cross with C. transvaalensis Burtt-Davy in the creation of F1 hybrid cultivars that are widely used on home lawns, golf courses, and sports fields worldwide. However, molecular information associated with adaptive and morphological traits in this species is limited. Accordingly, the objectives of this study were to identify genomic regions associated with establishment rate, spring green-up, drought response, leaf length and width, and stem internode length and width. In this study, we used a ‘A12359’ common bermudagrass high-density linkage map constructed with 3,544 markers. A total of 130 first-generation selfed progeny were evaluated in the field for two seasons for adaptive and morphological traits. A total of 36 genomic regions were identified to be associated with morphological, adaptive, and reproductive traits . The results provide important genetic resources towards understanding the molecular information associated with target traits as well as provide a foundation for using marker-assisted selection in bermudagrass breeding.
Speakers
SY

Shuhao Yu

Oklahoma State University
Friday September 27, 2024 12:35pm - 12:45pm HST
Coral 2

12:35pm HST

PH 3 - Effects of Harvest Regimes on Shelf-life and Quality of Rabbiteye Blueberries
Friday September 27, 2024 12:35pm - 12:45pm HST
Blueberry producers in the United States are facing high input costs and labor shortages, which have led them to mechanize several areas of blueberry production, particularly harvesting. Even though the use of machine harvesters is advantageous to producers and new technologies have been developed in recent years, several parts of the process still require improvements. One of the issues caused by the adoption of mechanical harvesting is increased harvest intervals, due to the high capital expenses associated with the purchase of such machinery that in turn leads to limited availability of harvesters to perform the harvest in a timely fashion. This trend may compromise berry quality, particularly in the Southeastern United States. Firmness is a critical factor in determining consumer preference, shelf life, and market value of fresh blueberries. The postharvest quality of blueberries is influenced by various factors, including genotype, postharvest handling, and harvest conditions such as harvest intervals. This study aimed to investigate the impact of different harvest-regimes on fruit quality and storability of ‘Brightwell’ blueberries. The experiment was conducted at the Alma Blueberry Research Farm, with a randomized complete block design. Fruit were hand-harvested at different intervals: T1: every 2 days, T2: every 3 days, and T3: every 7 days. Each treatment was replicated four times, resulting in nine harvests across all treatments. Following the harvest, the berries were sorted for defects, packed in clamshells, and stored at 1°C (34°F) and 85% relative humidity. Fruit quality parameters: firmness, fruit size, color, total soluble solids (TSS), titratable acidity, and fruit rot evaluation were evaluated at four different intervals: 1, 7, 14, and 21 days after harvest. Preliminary results indicate that fruit from the second and third harvests, T1 and T2 exhibited higher firmness readings at harvest compared to T3. Throughout the storage period, the firmness of the fruit was consistently higher in T2 compared to other treatments. A bigger fruit size was obtained at the first harvest of all treatments which declined after 14 days of storage in all three treatments. At the second harvest, T2 had the highest TSS but after 21 days of storage, TSS declined and T1 had the highest TSS after 21 days of storage in all three harvests. Additionally, T3 had a higher fruit rot incidence, and wet, sunken berries in the second and third harvests. So, a harvest interval of less than 7 days is recommended to maintain the fruit quality.
Speakers
AG

Amit Godara

The University of Georgia
Co-authors
AD

Angelos Deltsidis

The University of Georgia
ZR

Zilfina Rubio Ames

The University of Georgia
Friday September 27, 2024 12:35pm - 12:45pm HST
Lehua Suite

12:44pm HST

Viticulture and Small Fruits 2 (VSF 2)
Friday September 27, 2024 12:44pm - 1:45pm HST
Assessing the Viability of Olive Trees as an Alternative Fruit Crop for Cultivation in Florida  - Lorenzo Rossi
A Comparative Study of Ripening Timelines in Haskap (Lonicera caerulea L.) Cultivars. - Venkateswara Rao Kadium
Biostimulants Did Not Influence Strawberry Yield but Increased Fruit Sugar Content - Jayesh Samtani
Assessment of Botrytis Fruit Rot Susceptibility in Selected Strawberry Cultivars under Field Conditions - Jayesh Samtani
Evaluation of Cordon Training System in Blackberry Production - Jayesh Samtani
Effects of Chitosan and Ultraviolet A (UVA) Light on Postharvest of Blackcurrant Fruit - Venkateswara Rao Kadium
Updates on the Genome Database for Vaccinium (GDV): How GDV supports Vaccinium Research and Breeding - Roohollah Abdolshahi

Moderator
JS

Jayesh Samtani

Associate Professor, Virginia Tech
Friday September 27, 2024 12:44pm - 1:45pm HST
South Pacific 3

12:44pm HST

Genetics and Germplasm 4 (GG 4)
Friday September 27, 2024 12:44pm - 2:15pm HST
Safeguarding Herbaceous Ornamental Plant Diversity: The Ornamental Plant Germplasm Center - Yu Ma
SNP-Enabled Genetic Diversity and Population Structure of Gladiolus (Gladiolus ×hybridus) Cultivars - Marie Abbey
Development of Genetic Fingerprinting of Azalea Cultivars Using SSR Markers - Seth Wannemuehler
A Chromosome-Scale Haplotype-Resolved Reference Genome of Lantana camara and Insights into Unreduced Female Gamete Production - Brooks Parrish
Identification of Flowering Dogwood QTLs for Bract Color using a Pseudo-F2 Population - Trinity Hamm
Evaluation of Hibiscus cannabinus as an Alternative Fiber Crop for Florida: Identification of Valuable Traits and Germplasm for Cultivar Improvement - James Webb

Moderator
TH

Trinity Hamm

University of Tennessee, Knoxville
Friday September 27, 2024 12:44pm - 2:15pm HST
Coral 1

12:44pm HST

Growth Chambers and Controlled Environments 8 (CE 8)
Friday September 27, 2024 12:44pm - 2:15pm HST
Greenhouse supplemental lighting of lettuce and tomatoes to a target light intensity and daily light integral using dimmable LEDs - Neil Mattson
Hybrid Model for Forecasting Lettuce Yield in Indoor Vertical Farming - MD SHAMIM AHAMED
Rapid Controlled Environmental Propagation of Virus-Indexed Sweetpotato and Field Performance - Phillip Wadl
Development of a pH Management Protocol for Strawberry Mother Plants Grown in Deep Water Culture - Jennifer Boldt
Effect of Nutrient Correction Intervals on Nutrient Imbalance, Plant Growth, Yield, and Fruit Quality of Melon (Cucumis melo L.) in a Closed Hydroponic System - Minju Shin
Adjusting dissolved oxygen in nutrient solution for optimized kale and arugula growth in hydroponics - Kuan Qin
Developing Cardinal Temperatures for Leafy Green Growth and Development Parameters from Constant and Positive Day-Night Temperatures - Sean Tarr
Light Intensity Regulates the Interactive Effects between Far-red light and Temperature on Lettuce Growth, Morphology, Photosynthesis, and Secondary Metabolite - Sangjun Jeong
Moderator
NM

Neil Mattson

Cornell University
Friday September 27, 2024 12:44pm - 2:15pm HST
Nautilus 1

12:45pm HST

CITR - Modifications in Existing Nitrogen Recommendations for HLB-Affected Sweet Orange Trees in Florida
Friday September 27, 2024 12:45pm - 12:55pm HST
Florida stands as a significant player in the global citrus industry, boasting economic impacts of approximately 8.91 billion US dollars. Nevertheless, the citrus production in the state has been steadily decreasing since the onset of citrus greening (Huanglongbing, HLB) disease in 2005. Despite ongoing efforts, experts have yet to identify a potential cure for HLB, making the persistence of this disease a significant challenge for citrus production in Florida. In the wake of unavailability of a potential cure, different management strategies have been proposed aiming to minimize the HLB-induced adverse impacts on citrus plant growth and productivity and ensure the survival of citrus industry in Florida. In this context, effective nutrient management has emerged as a promising strategy for enhancing the performance of trees affected by HLB and sustaining a profitable yield. Fine root loss stands out as a primary concern in the management of HLB in citrus, as it impedes the plant's ability to uptake water and nutrients, resulting in nutritional imbalances. Effective nutrient management has the potential to effectively counterbalance the effects of fine root losses, thereby serving as a crucial factor in mitigating the adverse impacts of HLB on citrus trees. Therefore, this study has been initiated with the aim to evaluate the potential benefits of nutrient management on HLB affected mature Valencia sweet orange [Citrus sinensis (L.) Osbeck] trees. We seek to investigate the effects of different levels of nitrogen (N) i.e., 112, 168, 224, 280, 336 kg/ha on nutrient uptake, plant growth, fruit yield, juice quality, and overall performance of HLB-affected trees. In addition, nutrient mobilization in the soil in response to different levels of N has also been given critical consideration in order to evaluate the leaching potential of different nutrients and formulate mitigation strategies.
Speakers
NU

Noor Ul Basar

University of Florida
Co-authors
DM

Davie M Kadyampakeni

Univesity of Florida
NA
MA

Muhammad Adnan Shahid

Univesity of Florida
NA
Friday September 27, 2024 12:45pm - 12:55pm HST
Kahili

12:45pm HST

O/LT 2 - Alternate Products to Control Silvery Thread Moss in a Creeping Bentgrass Putting Green
Friday September 27, 2024 12:45pm - 12:55pm HST
Silvery thread moss (Byrum argenteum Hedw.) and others are considered cosmopolitan weeds of creeping bentgrass (Agrostis stoloniferous L.) golf putting greens. These putting green surfaces are vulnerable to moss infestations due to low mowing height, plant growth regulator applications, and restricted nitrogen all required for maintenance. On the actual putting surface, moss interrupts both golf ball roll and visual aesthetics. As a bryophyte, moss is a primitive photosynthetic plant without true leaves or roots and reproduce both sexually (sporophyte) and asexually (fragmentation). Early detection in putting greens is difficult because the protonema (the early stage of moss) resemble blue-green algae or Cyanobacteria. Once established, mosses can tolerate a range of environments from cool-to-hot, and wet-to-dry. Thus, mosses are a chronic problem of creeping bentgrass putting greens. In the past decade, the herbicide carfentrazone (QuickSilver; FMC Corp., Philadelphia, PA) has become the dominant strategy to suppress moss in putting greens, but requires multiple spray applications for efficacious control. In 2023 and 2024, a field study was conducted using a 25-year-old ‘L-93’ plus ‘Providence’ creeping bentgrass nursery green at North Shore Country Club (Glenview, IL). The objective was to explore moss control by two new granular products: Fiesta (chelated iron) and Castaway (tea saponin), both from The Andersons Inc. (Maumee, OH). Granular treatments at product label rate and QuickSilver at 3.35 fl oz/A were applied every 14 days for a total of 8 applications. QuickSilver was applied using a CO2-powered backpack sprayer operated at 40 psi with a three nozzle boom of XR TEEJET 8004VS applied in 2 gal water carrier/1000 sq ft. Year one evaluated granular products versus QuickSilver. Year two compared an additional standard of a once-applied spot treatment of baking soda (sodium bicarbonate) in solution. Both trials were arranged as a randomized complete block design with four replications per treatment. In 2023, Untreated, QuickSilver, Castaway, and Fiesta were evaluated. In 2024, two additional treatments were included of ½ rate Fiesta, and baking soda.. The results indicate that both Castaway and Fiesta granular products were capable of moss suppression in a putting green. Moss control with Fiesta was similar to the QuickSilver herbicide standard or spot treatment by baking soda. Therefore, these granular products could be used alone or in rotation with QuickSilver to control moss in golf course putting greens
Speakers
SS

Shehbaz Singh

Manager of Turfgrass research, Chicago District Golf Association
Co-authors
DS

Derek Settle

Chicago District Golf Association
NA
Friday September 27, 2024 12:45pm - 12:55pm HST
Coral 2

12:45pm HST

PH 3 - Facilitating Postharvest Elderberry Fruit Detachment with Ethylene
Friday September 27, 2024 12:45pm - 12:55pm HST
Interest in producing elderberry (Sambucus nigra ssp. canadensis) fruit in North America has increased in recent years, including the subtropical climate of Florida. The fruit contain high amounts of antioxidants in both the juice and solid fractions and are processed into a wide variety of products. Fruit grow in clusters (cymes) of 500 or more fruit (1-2 mm diameter) each, and typically ripen at different rates, depending upon when the flowers were fertilized, the variety/selection and weather conditions. This non-uniform ripening from green to deep purple challenges growers, since unripe fruit must be removed. Delaying cyme harvest until all fruit ripen is not feasible since overripe fruit abscise before unripe fruit ripen. Fruit are typically destemmed from the cymes the day of harvest, either manually or with mechanized systems. Destemming can cause significant loss of salable product as the fruit are often crushed, releasing juice. In a series of tests, we investigated the potential to promote uniform ripening and detachment of elderberry fruit by postharvest exposure to gaseous ethylene, commercially used to initiate ripening in climacteric fruit crops. At a commercial farm in Chiefland, Florida, small segments (approximately 30 fruit each) were cut from cymes with 75% ripe fruit from three elderberry genotypes (DNS11, DNS23 and DNS36). The samples were returned to the UF Postharvest Laboratory that day, divided into two treatment groups ( /- 100 ppm ethylene) and sealed in glass jars (n=3; 3 segments/jar) at 22 °C/95% relative humidity. Jars were opened after 24, 48 and 72 hr to avoid CO2 accumulation; at each timepoint, one jar was removed and fruit examined; remaining jars were resealed and ethylene concentration was reestablished. Exposure to ethylene significantly increased ripe fruit detachment after 24 hr, however partially ripe fruit ripened after 48 hr, irrespective of treatment. Fruit juice content was 46%, pH=5.0. Ethylene did not affect the following parameters, although there were differences in germplasm: soluble solids content (7-14%), total titratable acidity (0.44-0.70%), and total anthocyanin content (8-20 mg · g-1). Attached or detached fruit lost 6-10% weight after 24 hr, whereas stems lost about 50% weight; after 48 hr, shrivel symptoms appeared and weight loss roughly doubled for these same groups. Consideration must be given as to exposure to ethylene for 24 hr for easy fruit removal versus holding for 48 hr for ripening with accompanied higher weight loss and shriveling.
Speakers
SS

Steven Sargent

University of Florida
Professor and Extension Postharvest Specialist
Co-authors
AB

Adrian Berry

University of Florida
NA
AS

Ali Sarkhosh

University of Florida
NA
DJ

David Jarnagin

Hydemoer Co.
NA
KA

Kevin Athearn

University of Florida
NA
Friday September 27, 2024 12:45pm - 12:55pm HST
Lehua Suite

12:45pm HST

VSF 2 - Assessing the Viability of Olive Trees as an Alternative Fruit Crop for Cultivation in Florida
Friday September 27, 2024 12:45pm - 12:55pm HST
Over the past decade, the cultivation of olive trees (Olea europaea) in Florida has experienced remarkable growth, expanding tenfold. Currently, there are more than 60 growers tending to approximately 800 acres spread across 26 counties in Florida. Despite this significant expansion in Florida’s olive tree cultivation, accompanied by a surge in global olive oil demand, research in this area has been lacking. To address this gap, comprehensive data collection commenced in the summer of 2023 through three distinct trials located in Jay, Wauchula, and Fort Pierce, Florida. These trials aim to determine the most productive olive tree varieties and optimal cultivation techniques tailored to Florida’s diverse climate and soil compositions. Given variations in grove management approaches and tree maturity levels, a range of cultivars representing different genotypes were being tested across various locations. The cultivar ‘Arbequina’ was consistent across all trials. In addition to ‘Arbequina’, other cultivars such as ‘Koroneiki’ and ‘Sikitita’ were assessed in Wauchula, while ‘Lecciana’ and ‘Sikitita’ were examined in Fort Pierce. Throughout the trials, parameters including soil fertility, temperature, soil moisture levels, as well as leaf nutrient status and phenological observations were quantified twice a year. No nutrient deficiencies were detected in either soil or leaf samples, but also no consistent patterns regarding flowering or production were observed. The ongoing data collection is expected to shed light on critical aspects regarding the feasibility of olive tree cultivation within the Florida environment and provide valuable insights for growers and stakeholders.
Speakers
avatar for Lorenzo Rossi

Lorenzo Rossi

Assistant Professor, University of Florida
Dr. Rossi’s research program focuses on improving root health and growth on cultivated crops, leading to the development of environmentally sound and effective management methods. He is a horticulturist with specific expertise related to plant stress physiology, root dynamics and... Read More →
Co-authors
AB

Audrey Beany

UF/IFAS/IRREC
DK

Davie Kadyampakeni

University of Florida
NA
JF

John-Paul Fox

University of Florida
MG

Michael Garcia

Florida Olive Council, LAA
NA
Friday September 27, 2024 12:45pm - 12:55pm HST
South Pacific 3

12:45pm HST

CE 8 - Greenhouse supplemental lighting of lettuce and tomatoes to a target light intensity and daily light integral using dimmable LEDs
Friday September 27, 2024 12:45pm - 1:00pm HST
A previously developed algorithm controls on/off decisions for greenhouse supplemental light fixtures and retractable shade curtains to achieve a target daily light integral (DLI). The algorithm, termed LASSI (Light and Shade System Implementation) originally used high pressure sodium (HPS) lights with a 1-hour time step to avoid the warm-up time and reduced lifespan of HPS bulbs when they are frequently turned on/off. We have updated the algorithm accounting for dimmability of light emitting diodes (LEDs) for which light intensity can be adjusted in near real-time (RT LASSI). The objective of this study was to compare performance of lettuce ‘Rex’ and Rouxai’ and tomato ‘Sweetelle’ in response to the LASSI algorithm with HPS fixtures vs. RT LASSI with dimmable white LEDs. Experiments were conducted in adjacent greenhouses and DLI setpoints were 17 mol·m-2·d-1 for lettuce and 25 mol·m-2·d-1 for tomatoes. RT LASSI greenhouses had white LEDs (TSR Grow TG-600 HVR) and LASSI greenhouses had HPS fixtures (PL Light 1000 W). For treatments with RT LASSI, when supplemental lighting was called for, LED treatments were adjusted to complement sunlight to achieve a target instantaneous light intensity of 300 and 400 µmol·m-2·d-1 for lettuce and tomatoes, respective, averaged over a 10 minute interval. For tomatoes a minimum 4-hour dark period was imposed while for lettuce, supplemental lighting could occur anytime within the 24-hr period. For lettuce there were three replicate, 35 d crop cycles and for tomatoes plants received 15 weeks of treatment after reaching the fruiting stage with no replication. Both algorithms controlled DLI close to target. For lettuce, LASSI with HPS led to larger plant height and volume and increased fresh weight (but not dry weight) vs. RT LASSI with LED. For tomatoes, RT-LASSI with LED led to about a 30% greater tomato yield vs. LASSI with HPS. Increased yield was associated with increased fruit size but not increased fruit or truss number. Brix of HPS grown fruit was higher than LED fruit. While air temperature was very similar between both treatments, HPS fixtures may have increased plant temperature of LED. More research is needed to determine if plant impacts were due to type of lighting fixture and associated plant temperature and light spectrum or to the control algorithm itself (spreading supplemental lighting across greater hours per day).
Co-authors
NK

Nicholas Kaczmar

Cornell University
NA
TS

Timothy Shelford

Cornell University
NA
Friday September 27, 2024 12:45pm - 1:00pm HST
Nautilus 1

12:45pm HST

CHEX 2 - Will Consumers Purchase a Landscape Scouting Program?
Friday September 27, 2024 12:45pm - 1:00pm HST
The US landscape industry comprises 632,000 businesses with >1 million employees in 2022. The most common service landscape service providers (LSPs) perform is pest management. Over the past 25 years, consumers have increasingly requested that LSPs use more holistic approaches to pest management, including nonchemical and less toxic chemical control methods. Integrated pest management (IPM), specifically scouting, may be useful for LSPs to manage pests more sustainably and market new services, such as biological control releases. Little published literature details LSP scouting practices or consumer acceptance of scouting services. The goal of this study was to determine if IPM-aware consumers were more likely to purchase a scouting program offered by a LSP. A third-party panel service distributed an online survey across the United States. The final sample included 928 usable responses. Data were analyzed using a binary logistic regression model. Fifty-seven percent of respondents reported having some knowledge or that they were very knowledgeable of IPM. Increased consumer knowledge of IPM increased purchase likelihood. Respondents who self-reported “some knowledge” (5.6%) and “very knowledgeable” (8.6%) of IPM were more likely to buy scouting services. Respondents 65 years of age and older were 13.1% less likely to purchase a scouting service, regardless of IPM knowledge level. Consumers open to purchasing a scouting program, may also be more willing to allow a LSP to use a combination of chemical and nonchemical methods to manage pests. Further research is needed to determine consumer willingness to pay for scouting programs as well as non-chemical treatment options offered by LSP.
Speakers
AJ

Andrew Jeffers

Clemson University
I am a native of the mountains of eastern Tennessee. I have a B.S. in Agriculture – Plant and Soil Science, and M.S. in Plant and Soil Science from the University of Tennessee. My thesis project focused on woody tree and shrub liner production. I have worked as an herbaceous... Read More →
Co-authors
BB

Bridget Behe

Michigan State University
NA
MV

Michael Vassalos

Clemson University
NA
SW

Sarah White

Clemson University
NA
WB

William Bridges

Clemson University
NA
Friday September 27, 2024 12:45pm - 1:00pm HST
South Pacific 2

12:45pm HST

GG 4 - Safeguarding Herbaceous Ornamental Plant Diversity: The Ornamental Plant Germplasm Center
Friday September 27, 2024 12:45pm - 1:00pm HST
Ornamental crops play an indispensable role in enriching our daily lives, offering not just visual delight but also therapeutic benefits. Moreover, the floriculture industry stands as a pivotal pillar within the nation’s agriculture sector, experiencing a substantial 16% increase in sales from 2019-2022, marking it as one of the fastest-growing industries. Safeguarding ornamental plant diversity has become more crucial than ever to sustain this industry and ensure its continued growth and resilience in the face of climate changes and evolving consumer preferences. Located in Columbus, OH, the Ornamental Plant Germplasm Center (OPGC) is one of 20 gene banks in the U.S. National Plant Germplasm System. Established through a cooperative effort between the USDA-ARS and The Ohio State University, it began operations in 2001. The center’s main goals are to acquire, document, maintain, characterize, and distribute herbaceous ornamental genetic resources and associated information for conservation, and to enhance scientific research as well as the floriculture and nursery industry. Current priority genera include Begonia, Coreopsis, Lilium, Phlox, Rudbeckia, and Viola. Since the OPGC began operation, 7350 accessions have been acquired, representing significant diversity within the 432 genera and over 2000 species of herbaceous ornamentals conserved. More than 13,000 germplasm items have been delivered free of charge to researchers, breeders and educators around the world. This presentation will outline the core functions of OPGC, including its germplasm collection, conservation techniques, and collaborative research initiatives.
Speakers
YM

Yu Ma

Ohio State University
Co-authors
SS

Susan Stieve

The Ohio State University
NA
Friday September 27, 2024 12:45pm - 1:00pm HST
Coral 1

12:45pm HST

HIH - Evaluating the Needs and Barriers of Commercial Fruit and Vegetable Growers in Southwest Puerto Rico: A Qualitative Approach
Friday September 27, 2024 12:45pm - 1:00pm HST
According to the 2017 Census of Agriculture, the gross value of sales of fruits and vegetables produced in Puerto Rico totaled $52,127,495. Over 60% of these sales were generated in the island’s two main fruit and vegetable-producing regions, namely $25,351,987 in Region 4-Ponce and $7,948,690 in Region 8-San Germán (Census of Agriculture, 2017). This study examined the needs, barriers, and sources of information used by farmers in those regions. We employed a multiple-case research design and conducted in-depth interviews with 15 growers with diverse backgrounds and experiences (e.g., members of agricultural cooperatives, beginning farmers with four years of operation, smallholder farmers with less than 10 acres, farmers with large operations exceeding 250 acres, women-led farms, and farms with different production systems, such as conventional, certified organic, and agroecology). The Theory of Planned Behavior informed the interview protocol to capture attitudes, social norms, and perceived behavioral control affecting farmers’ intentions to continue producing fruit and vegetables in the short and long term. This study was approved by the Institutional Review Board (UF-IRB: 202102464/ UPRM-IRB: 2023010008), and informed consent was obtained from all participants. The interviews were transcribed and analyzed using Thematic Analysis. Our preliminary results indicate that the main barriers include issues related to (i) climate variability, (ii) labor, and (iii) market pricing and commercialization. Growers particularly emphasized experiencing crop damage, yield reductions, and sales losses due to climate shocks such as erratic weather patterns, drought, extreme heat, and an increase in the prevalence and severity of insect pests. Concerning labor, growers reported challenges in recruiting and retaining qualified and skilled workers, citing the high cost and administrative burden associated with the H-2A temporary agricultural workers program. Farmers, regardless of scale or production system, expressed difficulties due to recurrent oversupply of similar crops in the market, leading to the acceptance of lower prices. Additionally, growers highlighted issues related to the reliability, efficiency, and lack of distribution channels. Regarding sustainability in their production systems, most participants expressed a need for more information and dissemination of sustainable pest management practices. Notably, farmers’ most frequently utilized sources of information included videos, technical bulletins, and blogs available on the web. Our findings offer valuable insights for designing future outreach programs, developing research priorities, and formulating funding initiatives, with a specific focus on enhancing fruit and vegetable production systems in Puerto Rico.
Speakers
AL

Angela Linares Ramirez

University of Puerto Rico
Friday September 27, 2024 12:45pm - 1:00pm HST
South Pacific 1

12:45pm HST

VGBR 3 - Identification and Validation of Novel Resistance Loci to Fusarium oxysporum f.sp. lycopersici Race 3 in Tomatoes
Friday September 27, 2024 12:45pm - 1:00pm HST
Fusarium wilt disease caused by the soil-borne pathogen Fusarium oxysporum f. sp. lycopersici (Fol) is a major threat in tomato-producing regions that can lead to acute yield losses. Host resistance as compared to other control strategies provides an effective and reliable means to contain the spread of the pathogen. Given that genes that confer resistance to all the three known Fol races are single dominant genes, there is a risk of resistance breakdown by the mutating pathogen. Furthermore, in the face of imminent race 4 emergence, building a quantitative and durable resistance shield by pyramiding novel resistant genes in commercial cultivars becomes pertinent. S. pennellii has been previously identified as a repository for resistant genes to Fol3 and recently, two novel loci mapped at chromosomes 3 and 10 were identified from two accessions- LA 1522 and LA 750 respectively using bulk segregant analysis QTL seq. Preliminary analysis was conducted to develop molecular markers for both chromosomes and validate their co-segregation with the region of introgression associated with resistance. We found co-segregating markers for resistance harbored by chromosome 3 and designated the locus as I8. This marker therefore constitutes additional genomic resources for marker-assisted selection of this trait. Although we found markers that co-segregate with resistance on chromosome 10, we provide initial evidence that this resistance is the same with the I6 locus previously identified on chromosome 10 and derived from LA 716 while complementary phenotypic screens showed partial penetrance of this locus. Together, these resistance loci (I6 and I8) could constitute a qualitative shield against the pathogen in commercial cultivars. Efforts are underway to fine map these loci and characterize them under field conditions and against other previously known races.
Speakers
SI

Samuel Ipinyomi

University of Florida
NA
Co-authors
GV

Gary Vallad

University of Florida
NA
GM

Geoffrey Meru

University of Florida
NA
JC

Jessica ChitwoodBrown

University of Florida
SH

Samuel Hutton

University of Florida
NA
SL

Seonghee Lee

University of Florida
NA
Friday September 27, 2024 12:45pm - 1:00pm HST
South Pacific 4

12:55pm HST

CITR - Evaluating the Impact of Fabric Mulch Ground Cover on Grapefruit Tree Growth and Soil Characteristics in the Indian Rive
Friday September 27, 2024 12:55pm - 1:05pm HST
Florida citrus production and acreage have drastically decreased in the past years primarily due to citrus greening disease; consequently, citrus grove management has become more challenging and resource demanding. To increase soil health and restore tree and root health, new management practices have been implemented; in particular, a practice that has increased in use in the Indian River region is fabric mulch ground cover (FMGC). Potential advantages of FMGC include improved weed and pest control, reduced soil erosion, increased soil moisture and nutrient retention, reduced temperature extremes, and enhanced microbiome composition of the soil. Although the practice has been in use for almost ten years, little data has been scientifically collected from established groves. Hence, the goal of this trial is to evaluate the effects of FMGC on grapefruit tree growth and soil characteristics in the Indian River region. Four-year-old ‘Star Ruby’ (Citrus × paradisi) grapefruit trees grafted on ‘US-942’ (Citrus reticulata × Poncirus trifoliata) rootstock grown with or without FMGC were uniformly chosen for a two-year trial. A total of 20 trees were assigned to two treatments (FMGC vs. conventional). Leaf and soil nutrients, trunk diameter, height, canopy volume, and soil microbiome composition have been collected in the winter and summer. Gathered data showed initial differences in canopy volume, trunk diameter, and soil moisture between the two treatments. The trial will continue for an additional year, resulting in a greater understanding of the impact of this recently implemented management practice and its potential benefits to Florida citrus growers.
Speakers
AB

Audrey Beany

Biological Scientist, University of Florida
Co-authors
JF

John-Paul Fox

University of Florida
LR

Lorenzo Rossi

University of Florida
RA

Robert Adair

Florida Research Center for Agricultural Sustainability, Inc
NA
Friday September 27, 2024 12:55pm - 1:05pm HST
Kahili

12:55pm HST

O/LT 2 - Evaluation of Gypsum and Fertilizers for Enhanced Bermudagrass Performance Under Salinity Conditions in Florida Sandy Soils
Friday September 27, 2024 12:55pm - 1:05pm HST
Coastal regions, facing saltwater intrusion due to overpumping, exacerbate challenges for turf managers facing soil salinization, and sodium and bicarbonate hazards. Given the prevalence of gypsum applications to counter sodium hazard and the utilization of acidifying fertilizers for neutralizing bicarbonate hazards, there is a need to comprehensively evaluate the effectiveness of these strategies in alleviating soil salinity and bicarbonate hazards and their impact on turfgrass performance. An 8-week study was conducted at the University of Florida’s Fort Lauderdale Research and Education Center to assess the impact of ammonium sulfate and calcium nitrate, either alone or in combination with gypsum, on turfgrass performance and soil properties of a ‘Celebration’ bermudagrass fairway under salinity conditions. To replicate high salinity conditions, table salt (NaCl) was applied to half of the area at a rate of 5 lb of NaCl 1000 ft-2, with the rest of the area serving as a control. Gypsum was applied at a rate of 230 lb gypsum 1000 ft-2 and divided in two applications at mid-point (week 3) and prior to completion of the study (week 7). Fertilizers were applied at a rate of 0.5 lb N/1000 ft2. Salt and fertilizer were applied every two weeks, alternating between each other, for a total of four applications each. Experimental design was a split-split-split design with four replications, with salt serving as a main plot, gypsum as a sub-plot and fertilizer treatment as a sub-sub-plot. Turfgrass visual quality (1=worst, 9=best), normalized difference vegetation index (NDVI), percent green cover, and dark green color index (DGCI), turf injury, volumetric water content (VWC) and electrical conductivity (EC) were assessed weekly. Gypsum had no effect on turfgrass performance. Plots fertilized with AMS initially showed a higher quality than plots fertilized with calcium nitrate after fertilization, however no differences were found toward the end of the trial. Salt reduced turfgrass quality, NDVI and percent green cover and resulted in turfgrass injury, particularly following initial applications. However, it appears that the turfgrass gradually adapted to the salinity conditions, as turfgrass injury from salt decreased during the second half of the experiment. Volumetric water content and EC were affected by the interaction of salt and gypsum. During the experiment, plots treated with gypsum and salt consistently exhibited higher VWC and EC compared to plots that did not receive gypsum. Results suggest that disproportioned amounts of gypsum to improve turfgrass performance applied to golf courses are not justified.
Speakers
IA

I. Alejandra Sierra

University of Florida
Co-authors
MS

Marco Schiavon

University of Florida
Friday September 27, 2024 12:55pm - 1:05pm HST
Coral 2

12:55pm HST

PH 3 - Integrated Analyses of Transcriptomics and Lipidomics Reveal Potential Mechanisms Related to Physiological Disorders of
Friday September 27, 2024 12:55pm - 1:05pm HST
Hardy kiwifruit (Actinidia arguta) is highly sensitive to low temperatures, which can cause chilling injury (CI) as a physiological disorder. Peel surface pitting with black/dark brown spots was developed as CI symptoms in cold-stored hardy kiwifruit. In this study, we performed transcriptomic and lipidomic analyses to elucidate the potential mechanism of CI symptoms in cold-stored hardy kiwifruit. The peel tissues of hardy kiwifruit were collected after harvest (HV) and after cold storage; pitted peel tissues from CI-damaged fruit (PT) and healthy peel tissues from CI-unaffected fruit (HT) were also collected. Transcriptomic analysis identified 10,612 differential expressed genes (DEGs) between HV and HT tissues, and 3,206 DEGs were detected between HT and PT tissues. Among the 3,206 DEGs, 1,322 transcripts were up-regulated in HT tissues, while 1,874 transcripts were up-regulated in PT tissues. The KEGG pathway enriched by up-regulated DEGs in HT indicated protein modification, L-valine degradation, and polyol metabolism, while up-regulated DEGs in PT enriched alkaloid biosynthesis, protein modification, and lipid metabolism. In lipidomics analysis, a total of 101 lipids clustered into 14 subgroups were detected in peel tissues of cold-stored hardy kiwifruit. Based on the results of VIP scores (> 1.5), the levels of triacylglycerol (TAG) 54:8, TAG 54:9, phosphatidylcholine (PC) 36:4, PC 34:2, PC 36:5, PC 34:3, and TAG 54:7 were higher in PT tissues, but the levels of phosphatidylethanolamine (PE) 36:2, phosphatidylserine (PS) 38:3, PS 36:0, PC 36:1, PE 34:1, and PE 36:1, were higher in HT tissues, compared with the other tissues. Therefore, the results indicated that the CI symptoms in cold-stored hardy kiwifruit would be derived from integrated transcriptomic and lipidomic results.
Speakers
HP

Hyowon Park

Chung-Ang University
Co-authors
HJ

Hyun Ji Eo

National Institute of Forest Science
NA
JE

Jane E. Stewart

Colorado State University
NA
avatar for Jinwook Lee

Jinwook Lee

Professor, Chung-Ang University
NA
JR

Jorge R. Ibarra Caballero

Colorado State University
NA
UL

Uk Lee

National Institute of Forest Science
NA
Friday September 27, 2024 12:55pm - 1:05pm HST
Lehua Suite

12:55pm HST

VSF 2 - A Comparative Study of Ripening Timelines in Haskap (Lonicera caerulea L.) Cultivars.
Friday September 27, 2024 12:55pm - 1:05pm HST
Haskap (Lonicera caerulea L.), also known as edible blue honeysuckle or honeyberry, is a new and emerging berry crop in North America. Its resilience to cold temperatures, adaptability to various soil pH levels, distinctive flavor, and health benefits make it suitable for cultivation in colder climates. The period from flowering to fruit ripeness is remarkably brief in haskap, typically ranging from six to eight weeks, offering an advantageous alternative in shorter-growing regions. Yet, detailed guidance on its cultivation and fruit quality is scarce. To aid growers, a two-year study at the Western Agricultural Research Center assessed the ripening timelines of 15 haskap varieties, providing critical data to optimize harvest timing and management practices. Throughout the growing seasons of 2022 and 2023, from May through August, fruit quality and ripening stages were closely monitored two to three times a week by collecting berry samples. From these samples, traits such as total soluble solids content (Brix), pH, total acidity (TA), single berry mass, and berry color changes were measured. Assessment of this phenotypic data revealed distinct patterns for each trait across the different varieties studied. Cultivars such as 'Blue Goose', 'Boreal Beauty', and 'Sugar Mountain Blue' reached their harvest readiness sooner, around approximately 650 growing degree days (GDD) for the year, followed by a reduction in berry size due to water loss and a rise in sugar concentration. In contrast, Aurora, Tana, and Kawai matured more slowly, achieving peak ripeness near ~1000 GDD. Yet, they preserved their mature fruit characteristics (consistent berry weight and sugar levels) through the sampling period’s end. These insights into the ripening patterns of haskap varieties from prominent breeding programs in North America can inform growers as they choose specific cultivars and decide on optimal harvest times.
Speakers
VR

Venkateswara Rao Kadium

Montana State University
Co-authors
AS

Andrej Svyantek

Montana State University
NA
ZM

Zach Miller

Montana State University
NA
ZW

Zhuoyu Wang

Montana State University
NA
Friday September 27, 2024 12:55pm - 1:05pm HST
South Pacific 3

1:00pm HST

CE 8 - Hybrid Model for Forecasting Lettuce Yield in Indoor Vertical Farming
Friday September 27, 2024 1:00pm - 1:15pm HST
The surging demand for sustainable agriculture has accelerated the adoption of indoor vertical farming as a pragmatic solution. Lettuce, a cornerstone crop in this context, assumes significant importance. Accurate forecasting of lettuce yield is indispensable for optimizing resource allocation and ensuring a steady supply. Most existing models used either environmental data or images to predict yield predictions, which could be erroneous for complex systems. This study aims to improve the accuracy of yield prediction in indoor farming settings with a hybrid model. First, we applied the feedforward neural network and random forest models for yield prediction, leveraging data from environmental sensors, cultivation practices, and historical yield records. Then, a convolutional neural network model is tailored to forecast yield using image data captured by RGBD cameras. Based on our results, we found reasonable accuracy in terms of RMSE and MAE, which range between 10-25 gm and 28-49 g, respectively. By amalgamating these diverse models, we aim to elevate yield prediction accuracy. It’s hypothesized that the proposed hybrid model would outperform individual approaches, offering invaluable insights for indoor vertical farming operations decision-making.
Speakers
MS

MD SHAMIM AHAMED

University of California, Davis
Friday September 27, 2024 1:00pm - 1:15pm HST
Nautilus 1

1:00pm HST

CHEX 2 - Native Plant Extension Programming for Commercial Horticulture Professionals
Friday September 27, 2024 1:00pm - 1:15pm HST
Native plants are becoming increasingly popular choices for low-input ornamental landscapes in residential and commercial applications. Many nurseries and landscape professionals are currently growing or offering at least some native plants in response to this increasing demand. However, supplies are still limited and there are specific best management practices associated with growing, marketing, and maintaining native plants that need further development. In response to this need from the green industry, replicable, applied programming focused on supporting growers who are currently producing or have an interest in producing native plants was developed. To first prioritize the needs of the industry, a state-wide native plant needs assessment survey was developed and disseminated to nursery and landscape professionals. The survey received 60 responses and indicated that native alternatives to invasive species, deer resistant native plants, and new cultivars of native plants were among the top priorities, in addition to IPM practices, stress tolerance, and propagation protocols. Based on this direction from stakeholders, extension programming was developed to meet these needs and support the green industry in their production and marketing of native plants. Educational programs focused on commercial native plant production and management were developed and delivered both in-person and virtually through webinars, while twilight meetings, including sessions at established native plant nurseries, facilitated grower-to-grower learning and interaction. Program evaluation surveys indicated strong metrics for knowledge gain, incorporating more native plants in their operations, reducing inputs, and achieving better pest control measures. Field trials comparing cultivars of deer-resistant native ornamental grasses offered growers and landscapers a chance to observe how these plants performed throughout three growing seasons, while offering a low-input alternative to non-native species in the landscape. Propagation trials were conducted to begin optimizing protocols for both vegetative cuttings and seed propagation of locally collected native ornamental plants, with success rates documented for each species using standard propagation protocols. A video was also created and shared with stakeholders showcasing a virtual tour of a commercial golf resort that has successfully incorporated native plants into their landscape, thus serving as an example for how to achieve an ornamental landscape aesthetic using native species. While native plant species may vary among ecoregions, this comprehensive approach is replicable and has been met with a high degree of satisfaction from commercial horticulture professionals.
Speakers
WE

William Errickson

Rutgers University
Co-authors
MB

Michele Bakacs

Rutgers University
NA
TW

Timothy Waller

Rutgers University
Timothy J Waller, Ph.D. is serving in his fourth year as the Commercial Nursery Agent of Rutgers Cooperative Extension in southern NJ, based out of Cumberland County. Tim has a Ph.D. in Plant Biology with a focus on fungal plant pathology and has been a licensed pesticide applicator... Read More →
Friday September 27, 2024 1:00pm - 1:15pm HST
South Pacific 2

1:00pm HST

GG 4 - SNP-Enabled Genetic Diversity and Population Structure of Gladiolus (Gladiolus ×hybridus) Cultivars
Friday September 27, 2024 1:00pm - 1:15pm HST
Studies on genetic diversity and population structure provide important insights for determining ancestry and target trait enhancement in breeding programs. Gladiolus(-i), Gladiolus ×hybridus (Iridaceae), is a tetraploid, asexually-propagated, herbaceous perennial floricultural crop. Gladioli have tall flower stalks which make them ideally suited for cut flowers (floral design) and annual garden plants. Gladiolus is an important cut flower crop (in the top 5) for floral design. The purpose of this study was to analyze the genetic diversity of cultivated gladiolus germplasm to determine ancestry and relatedness. In this study we examine 549 unique gladiolus cultivars using DNA marker-based analysis. Samples were collected from the public (University of Minnesota) and private (Meyer, Otto) sector breeding programs in Minnesota and Europe. Population genetic diversity was analyzed using 17,556 single nucleotide polymorphism (SNP) markers developed by low-density DArTseq technology. Despite phenotypic differences, primarily in flower color or type (ruffled, etc.), the genetic diversity of gladiolus cultivars is low. The heterozygosity value was Ho=0.09 and the Fischers (FHOM) inbreeding coefficient was FHOM=0.40. SplitsTrees showed no differentiation, the average minor allele frequency (MAF) and polymorphism information content (PIC) was MAF=0.12 and PIC=0.15. The lack of significant genetic diversity among cultivars as well as breeding programs demonstrates a narrow germplasm base for this important cut flower crop. We discuss our findings and recommend ways to use these conclusions to improve future genome-wide association studies (GWAS) as well as increase efficiency and diversity in breeding goals.
Speakers
MA

Marie Abbey

University of Minnesota
Marie Abbey is a researcher at the University of Minnesota Horticultural Science department. She has studied perceptions of biotechnology, invasive plant species, and aquaponics. Her current research is in flower breeding and molecular genetics.
Co-authors
NO

Neil O Anderson

University of Minnesota
NA
RE

Rajmund Eperjesi

University of Minnesota
NA
Friday September 27, 2024 1:00pm - 1:15pm HST
Coral 1

1:00pm HST

HIH - Soilborne Disease, Plant-parasitic Nematode, Insect Pest, and Weed Challenges Faced by High Tunnel Growers and Preferred Strategies to Overcome Those Challenges: Preliminary Results from a Kentucky Farmer Survey
Friday September 27, 2024 1:00pm - 1:15pm HST
Small farms in Kentucky use high tunnels (HTs) to help increase farm profitability and resilience and give them the ability to extend their growing season for year-round production of high-value specialty crops. Although HTs are semi-permanent structures, many are never moved due to land constraints, the time and labor required to move them, and because corner posts are often cemented into the ground to secure the structure from weather events. The continuous cropping in non-rotated soil can intensify pathogen, insect pest, and weed population densities. The multiple benefits of HTs may be reduced or disappear when soilborne pest pressure increases. We conducted a survey of Kentucky vegetable growers between January and March 2024 to assess production challenges faced when growing vegetables in high tunnels, specifically those related to soilborne diseases, plant-parasitic nematodes, insect pests, and weeds, and the preferred strategies to manage those challenges. We had a particular interest in assessing farmers' use or willingness to use soil solarization as a strategy to manage these issues in high tunnels. Farmers were surveyed using both web-based and mail versions of the survey. We targeted producers growing high-valued crops in their high tunnels, specifically tomato, lettuce, and leafy greens. Preliminary results suggest that common soilborne diseases faced by survey respondents include Sclerotinia spp. A large percentage of respondents indicated they have not had or they do not know if they have soilborne diseases or plant-parasitic nematodes. Regarding insect pests, the most common pests faced by survey respondents are aphids and whiteflies. Finally, common weed problems faced by survey respondents include pigweed, crabgrass, and chickweed. Common strategies used by respondents to address these problems include fungicides, insecticides, and hand weeding. Regarding soil solarization, only a small percentage of respondents are using or have used soil solarization. Nonetheless, more than 75% of those respondents who are not using or have not used soil solarization are willing to use soil solarization. The two most important reasons for wanting to use soil solarization include interest in using more environmentally friendly practices and the belief that soil solarization might be cheaper and more effective in managing weeds, insect pests, diseases and /or plant-parasitic nematodes in high tunnels.
Speakers
MV

Margarita Velandia

The University of Tennessee
NA
Co-authors
AW

Annette Wszelaki

The University of Tennessee
NA
RR

Rachel Rudolph

University of Kentucky
NA
SS

Susan Schexnayder

The University of Tennessee
NA
Friday September 27, 2024 1:00pm - 1:15pm HST
South Pacific 1

1:00pm HST

VGBR 3 - Enhancing Fusarium Wilt Race 2-Resistance and Brix Content in Watermelon through Genomic Selection
Friday September 27, 2024 1:00pm - 1:15pm HST
Complex traits in plants are influenced by many genes, each having a small impact. Using marker-assisted selection (MAS) alone is not sufficient to improve these traits in elite cultivars. Genomic selection (GS) is a promising breeding approach for enhancing complex traits like resistance to Fusarium oxysporum f. sp. niveum (Fon) race 2 and increasing sugar levels (brix content) in watermelon. In our study, we wanted to see how well GS can predict disease resistance and sugar levels in an interspecific citron melon (Citrullus amarus) by cultivated watermelon (Citrullus lanatus) population. We created an F2:3 population by crossing USVL252-FR2 (resistant to Fon race 2, low brix; C. amarus) with ‘Sugar Baby’ (susceptible to Fon race 2, high brix; C. lanatus). We tested disease resistance in a growth chamber and measured sugar levels in a field trial using a randomized complete block design of the F3 families. We resequenced the DNA of 150 F2 plants to identify genetic differences. Disease response was assessed 28 days after inoculation, and sugar levels were measured with a brix meter to gauge sweetness. To predict disease resistance, we used two genomic models - Random Forest and GBLUP - which we found to be effective in previous studies. We compared the performance of univariate models (looking at disease and sugar levels separately) and bivariate models (looking at disease and sugar levels together) to identify the best approach for selecting superior cultivars based on these traits. We assessed model performance using ten-fold cross-validation. Our goal is to focus on these important polygenic traits and select superior genotypes early in breeding to develop watermelon cultivars with improved disease resistance and high sugar content.
Speakers
AB

Anju Biswas

USDA-ARS
NA
Co-authors
AL

Amnon Levi

USDA-ARS
NA
HH

Hannah Houston

USDA-ARS
NA
PW

Patrick Wechter

Clemson University
NA
SB

Sandra Branham

Clemson University
NA
Friday September 27, 2024 1:00pm - 1:15pm HST
South Pacific 4

1:05pm HST

CITR - High-throughput Phenotyping and Fruit Juice Quality of 'OLL-8' Sweet Orange Scion on Different Rootstocks with Compariso
Friday September 27, 2024 1:05pm - 1:15pm HST
The Florida citrus industry has seen a 90% decline in fruit production, following the first identification of huanglongbing (HLB) in 2005. Sweet orange (Citrus sinensis) cultivars make up a majority of the juice industry and are known to be susceptible to HLB; therefore, new tolerant or resistant cultivars or crop protection treatments need to be explored. Of the sweet orange cultivars released by UF Institute of Food and Agricultural Sciences, ‘OLL’ lines have shown some potential tolerance to this disease in cultivar field trials. High-throughput phenotyping revealed that nearly 14% of top performing trees across roughly 90 different research blocks in Florida, were accessions derived from the original ‘OLL’ tree. Of these trees, ‘OLL-8’ represents 11% of top performing trees across these different research blocks. This research explores the effects of different rootstocks in combination with the ‘OLL-8’ scion. Three UF rootstocks (‘UFR-2’, ‘UFR-4’ and ‘UFR-6) and three industry standard rootstocks (‘US-897’, ‘US-942’ and ‘Swingle’) were compared. For each rootstock, 12 mature trees, across three different blocks were compared across three different time intervals during the 2023 and 2024 ‘Valencia’ harvest seasons at a field trial in Lake Alfred, Florida. In 2024, the same 12 mature trees per rootstock were compared with trees that received oxytetracycline injections following the previous harvest season. Data was collected on juice quality variables including total soluble solids, titratable acidity in citric acid equivalents, sugar:acid ratio, pounds solids per box, percent juice, and color as well as on external fruit quality data parameters such as mass, diameter, length, and color. Data were analyzed to determine statistically significant differences among the different rootstocks evaluated. To determine differences in tree health, high-throughput phenotyping via drone flight occurred in December of 2023 and March of 2024 and included variables such as tree count, measurements of canopy area and volume, normalized difference vegetation index (NDVI), and normalized difference red edge index (NDRE). There was evidence for statistically significant differences for various traits among the rootstock combinations evaluated in this study.
Speakers
EW

Emily Worbington

University of Florida-IFAS CREC
Co-authors
HH

Heaven Heflin

University of Florida/IFAS-Citrus Research and Education Center
NA
JV

Joe Volpe

University of Florida
JC

John Chater

University of Florida
Friday September 27, 2024 1:05pm - 1:15pm HST
Kahili

1:05pm HST

O/LT 2 - Cold-hardiness, Flowering, and Disease Resistance of 24 Camellia Cultivars and Selections in Tennessee, USA
Friday September 27, 2024 1:05pm - 1:15pm HST
Cold hardiness, flowering, and disease resistance of ornamental camellia (Camellia spp.) cultivars are poorly documented when grown in a climate subjected to occasional -18°C (0°F) temperatures. To comprehensively understand cold-hardiness, flowering, and disease resistance, 24 cultivars and selections of camellia species and hybrids were evaluated in McMinnville, TN, USA (USDA Hardiness Zone 7a). Camellias were planted in field plots in Mar 2011, evaluated for flowering from year 2011 to 2020, and rated for low-temperature damage in 2014 and 2023. The Camellia Yellow Mottle Virus, monochaetia leaf spot (Monochaetia sp.), edema, flower blight (Ciborinia camelliae), and flower spot (Botrytis cinerea) severity (% affected) were evaluated from Oct to Nov in 2016 and 2017, and the season-long area under the disease progress curve (AUDPC) was calculated. ‘April Remembered’, ‘April Rose’, ‘Arctic Snow’, ‘Ashton’s Ballet’, ‘Autumn Carnival’, ‘Autumn Spirit’, ‘Elaine Lee’, ‘Survivor’, and a C. chekiangoleosa selection were least affected by low winter temperatures, whereas ‘Korean Snow’, ‘One Alone’, a C. sasanqua selection, ‘Pink Icicle’, and ‘Shishigashira’ were severely damaged. Cultivars that flowered most reliably (5 to 6 of 8 years) included ‘Arctic Snow’, ‘April Remembered’, ‘April Rose’, ‘Ashton’s Ballet’, ‘Autumn Spirit’, and ‘Survivor’, whereas ‘Maroon Mist’, ‘One Alone’, and ‘Shishigashira’ never flowered. ‘Korean Fire’, ‘Classic Pink’, ‘Maroon Mist’, and ‘Spring’s Promise’ displayed the highest virus severity and AUDPC. ‘Arctic Snow’, a C. sasanqua selection, and a C. chekiangoleosa selection had no viral symptoms. A C. sasanqua selection and ‘Red Aurora’ were significantly impacted by edema disorder, with severity ratings of ∼43% and 26%, respectively. Monochaetia leaf spot severity was highest in ‘Red Aurora’ and ‘Spring’s Promise’, whereas ‘Anacostia’, ‘Arctic Snow’, ‘Ashton’s Ballet’, ‘Autumn Spirit’, ‘Classic Pink’, ‘Kuro Delight’, ‘One Alone’, ‘Pink Icicle’, ‘Shishigashira’, and ‘Survivor’ exhibited the least monochaetia leaf spot severity and AUDPC. Flower blight and flower spot were observed only in ‘Arctic Snow’ and ‘Survivor’. These findings will aid landscapers and nursery growers with selecting and managing camellia cultivars effectively.
Speakers
JS

Jacob Shreckhise

USDA-ARS, U.S. National Arboretum
Co-authors
DF

Donna Fare

USDA-ARS, U.S. National Arboretum (Retired)
NA
FB

Fulya Baysal-Gurel

Tennessee State University
NA
MP

Madhav Parajuli

USDA-ARS, U.S. National Arboretum
NA
Friday September 27, 2024 1:05pm - 1:15pm HST
Coral 2

1:05pm HST

PH 3 - β-Cyclodextrin Nano-encapsulated Carvacrol Inclusion Complexes Improve Postharvest Quality of Limes
Friday September 27, 2024 1:05pm - 1:15pm HST
The ripening and senescence of fresh fruit and vegetables are inevitable during storage, transportation, and sale, which will reduce their marketability and cause substantial economic losses. The infection of pathogenic microorganisms can also lead to food safety problems. Plant essential oils are considered a promising strategy to preserve fresh produce. However, their application is limited by several aspects, including high volatility, low solubility, off flavor, etc. Encapsulation technology has emerged as a promising solution to alleviate these limitations. Nanoencapsulation is a delivery system for bioactive compounds that is usually employed to support the stability of the agents, maximize their retention, and control the release of the compounds at the target locations. A nanoemulsion composed of carvacrol and β-cyclodextrin was prepared by an ultrasound-mediated method, and the encapsulation process was conducted using a Buchi® Nano Spray Dryer B-90. The inclusion complex powder was collected and filled to air-permeable sachets. The sachets were then fixed inside commercial clamshells containing limes to simulate shelf-life. Fruit quality and total microbial population were analyzed. The results showed that the dimensions of spray-dried powders were primarily at nanoscale. The encapsulation process did not affect the antimicrobial and antioxidant activities of carvacrol. The nanocapsules prolonged the release of carvacrol. It effectively delayed the rapid color deterioration of limes without causing phytotoxicity, and maintained lime quality with higher firmness and lower weight loss. Free carvacrol and carvacrol/β-cyclodextrin treatments significantly reduced the growth of P. digitatum and total bacteria on fruit peel and inside of the wounds. However, the GC-MS results showed carvacrol residue detected from free carvacrol-treated fruit, but not from the carvacrol/β-cyclodextrin-treated fruit. The results indicate that nano-encapsulated carvacrol/β-cyclodextrin inclusion complexes can be applied as an effective strategy to preserve postharvest produce. Keywords: Nanoencapsulation, nano spray drying, essential oil, postharvest quality, lime
Speakers
CS

Chang Shu

USDA-Agricultural Research Service-Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
Co-authors
XS

Xiuxiu Sun

USDA-Agricultural Research Service-Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
NA
Friday September 27, 2024 1:05pm - 1:15pm HST
Lehua Suite

1:05pm HST

VSF 2 - Assessment of Botrytis Fruit Rot Susceptibility in Selected Strawberry Cultivars under Field Conditions
Friday September 27, 2024 1:05pm - 1:15pm HST
Botrytis fruit rot (BFR) or grey mold disease, caused by Botrytis cinerea Pers., poses a significant threat to strawberry crop production in the mid-Atlantic region of the U.S. The extensive use of fungicides to combat this fungal disease has resulted in listing the strawberries in the Dirty Dozen fruits and the evolution of fungal strain resistance to fungicides. Hence, exploring potential alternative strategies is crucial to reducing pesticide use and minimizing BFR; as such, utilizing resistant plant cultivars is a potential strategy. With this, the current study aimed to assess the susceptibility of two cultivars to Botrytis, Flavorfest, and Honeoye, which showed resistance to gray mold under in vitro conditions, and compare them with grower standard cultivars, Chandler and Sweet Charlie, under field conditions. The field evaluations were conducted at two locations during the 2022-2023 growing season: Hampton Roads Agriculture Research and Extension Center in Virginia Beach, VA, and a grower farm in Fredericksburg, VA. Transplanting of plants was done on October 12, 2022, in Fredericksburg and October 17, 2022, in Virginia Beach. A randomized complete block design was used in the experiments with four replicates per cultivar in Virginia Beach and three replicates in Fredericksburg, and each replicate had 12 plants. Fruits were harvested twice a week throughout the season to assess BFR occurrence and marketable crop yield. The main effect of the cultivar was significant for Botrytis fruit rot and marketable yield for the season. 'Honeoye' showed the lowest BFR-infested fruits (~6.5 g of fruits/plant), compared to 'Chandler' (22.5 g). However, 'Chandler' showed the highest marketable yield (713 g/plant), followed by 'Sweet Charlie' (473 g), while 'Flavorfest' (261 g) and 'Honeoye' (216 g) produced the lowest yields. Additionally, marketable yield differed by location, with higher yields recorded in Virginia Beach. Post harvest parameters including fruit firmness, total soluble solids (TSS), and pH that were measured on a subsample of fruits in Virginia Beach showed significant cultivar effect . ‘Honeoye’ had the least firm fruit but had the highest TSS for the season, not different than ‘Sweet Charlie’. The fruit pH of ‘Sweet Charlie’ was the highest. Information on resistant cultivars could assist growers in choosing appropriate cultivars to meet their farm production practices.
Speakers
JS

Jayesh Samtani

Associate Professor, Virginia Tech
Co-authors
AV

Amaranatha Vennapusa

Delaware State University
NA
BA

Baker Aljawasim

Virginia Tech
NA
GS

George Snead

Braehead Farm, Inc.
NA
KM

Kalpalatha Melmaiee

Delaware State University
NA
PR

Patricia Richardson

Virginia Tech
NA
Friday September 27, 2024 1:05pm - 1:15pm HST
South Pacific 3

1:15pm HST

CITR - Assessing Tree and Root Responses of Various HLB-affected Citrus Cultivars Using Oxytetracycline Trunk Injections
Friday September 27, 2024 1:15pm - 1:25pm HST
The citrus industry across the globe, including Florida, has been severely affected by the citrus greening disease (Huanglongbing, HLB), which is associated with the bacterium Candidatus Liberibacter asiaticus (CLas) and vectored by the Asian citrus psyllid. While no single method has been found to completely control CLas, ways to mitigate its effects on citrus trees have been increasingly studied. One recent management method that has been attracting attention is oxytetracycline (OTC) trunk injections. While initial research has shown that OTC trunk injections have been able to reduce HLB symptoms, there have been some inconsistencies about the extent of that reduction between different cultivars. A limited number of cultivars have been studied, mainly focusing on the sweet oranges ‘Valencia’ and ‘Hamlin’. The limited cultivars injected that are closely genetically related may cause differences in the effectiveness of treatment. There is a gap in knowledge about how OTC treatments affect cultivars with diverse genetic backgrounds. The aim of this study was to investigate the effects of OTC trunk injections on above and belowground tree health of various United States Department of Agriculture developed citrus cultivars. A completely randomized experimental design comprising 10-year-old mandarin, grapefruit, and sweet orange-like cultivars grafted on ‘US-942’ and ‘US-812’ rootstocks was used to study OTC trunk injection rates applied once a year at the recommended label concentrations (n = 21). Similarly, trees from the same cultivars grafted on the same rootstocks not receiving any injections were used as controls (n = 21). Throughout the experiment, above and belowground components were analyzed for any changes. Aboveground measurements included tree health within and between cultivars: canopy dimensions, leaf CLas titer, fruit size, drop and harvest count, and OTC residue in leaves. Belowground measurements included analysis of root and microbiome health by observing root density, root CLas titer, root OTC residue, and microbiome population diversity. The results are helping researchers to utilize OTC trunk injections more effectively.
Speakers
GB

Giancarlo Buzzi

University of Florida
Co-authors
LR

Lorenzo Rossi

University of Florida
MM

Matthew Mattia

US Department of Agriculture
Friday September 27, 2024 1:15pm - 1:25pm HST
Kahili

1:15pm HST

O/LT 2 - The American Rose Trials for Sustainability® (A.R.T.S.®) Program Announces Five Winning Roses for 2025
Friday September 27, 2024 1:15pm - 1:25pm HST
The American Rose Trials for Sustainability® (A.R.T.S.®) is a US rose trialing program in its eighth year of announcing winning roses. A.R.T.S.® evaluates newer roses in the marketplace using scientific methodology (blocking, randomization, control cultivars, etc.). Roses are evaluated over two growing seasons and are grown using minimal inputs (i.e. no pesticides, no deadheading, etc.). Entries that score equal to or higher than the control cultivars (Double Knock Out® [‘RADtko’] and Sunrise Sunset™ [‘BAIset’]) and have >50% survival by the end of the trial period, earn regional Local Artist awards. Roses winning in four or more Köppen climate regions earn Master Rose awards. The 2025 award winning roses were planted in 2022. Data was collected monthly during the 2022 and 2023 growing seasons on floral attributes (42.5% of score), foliar health and quality (45% of score), and growth habit (12.5% of score). There were six trial sites representing five US Köppen climate regions (Cfa, Csa, Dfa, Dfb, and H). Five roses won 2025 A.R.T.S.® Local Artist awards: Arctic Blue™ (‘WEKblufytirar’; Csa), Easy to Please™ ('WEKfawibyblu'; Cfa), Pretty Polly® Lavender (‘ZLEpolthree’; Dfa), Sunset Horizon™ (‘MEIsistoma’; Dfa and Dfb), and True Bloom™ True Friendship™ (‘ALTmine’; Csa and Dfa). Performance data will be provided by region for the two control and five winning rose cultivars.
Speakers
KL

Kristine Lang

South Dakota State University
Co-authors
DZ

David Zlesak

University of WI River Falls
GH

Gaye Hammond

Houston Rose Society
NA
GP

Gregory Pongetti

Arboretum and Botanical Garden at Cal State Fullerton
NA
JS

Jeff S. Kuehny

LSU AgCenter Botanic Gardens at Burden
NA
JC

Jessica Clonninger

Boerner Botanical Gardens
NA
JL

Jessie Liebenguth

Reiman Gardens-Iowa State University
NA
PD

Patrick Dahl

Chicago Botanic Garden
NA
RS

Randy S. Nelson

University of Minnesota- Crookston
NA
RH

Richard Hawke

Chicago Botanic Garden
NA
SM

Shaun Moser

Conservation Garden Park
NA
SG

Steve George

Texas A
NA
SW

Susan Worthey

Magnolia Botanical Garden- Mississippi State University
NA
WE

Wanda E. Ellis

LSU AgCenter Botanic Gardens at Burden
NA
Friday September 27, 2024 1:15pm - 1:25pm HST
Coral 2

1:15pm HST

PH 3 - Nondestructive Detection of Chilling Injury Based on VIS/NIR Spectroscopy in Sweet Potato
Friday September 27, 2024 1:15pm - 1:25pm HST
Sweet potato (Ipomoea batatas L.) is one of the seven major food crops grown worldwide. The optimal storage temperature for sweet potatoes is 12-15℃, and chilling injury occur when it falls below 10℃. The initial symptom of chilling injury in sweet potatoes is difficult to discern in visual judgment and requires checking through a cut-off sections. Therefore, this study intended to develop a non-destructive chilling injury prediction model using VIS/NIR spectroscopy sensors. USB4000 Fiber Optical Spectrometer was used for collecting spectrum data in the wavelength of the visible to near-infrared region (400 nm to 1100 nm), and the average value was used by measuring six areas divided into upper, middle, and lower parts to reduce errors. Firmness, total soluble solids, internal chromaticity, chilling index, and Malondialdehyde (MDA) were measured as reference data, and Partial Least Squares Regression(PLSR) method was used for prediction. To increase the accuracy of the model, the near-infrared spectrum data were preprocessed using the Savitzky–Golay 1st and 2nd derivatives (S–G), standard normal variate (SNV), and multiplicative scattering correction (MSC) methods. Excellent performance models for each preprocessing methods were selected, and as a result of verification through the prediction model, the 'Hogammi' variety showed excellent performance in the preprocessing of Savitzky-Golay 2st derivative in TSS and Malondialdehyde (MDA), and CI index showed the best performance in the processing of SNV. As indicators of chilling injury such as the CI index involve subjective opinions of experimenters, the findings of this study could be used as a fundamental step to develop more objective and accurate chilling injury prediction models by including various internal indicators.
Speakers
JL

jonghwan lee

kangwon national university
Co-authors
CJ

CheonSoon Jeong

kangwon national university
NA
HC

HanRyul Choi

National Institute of Horticultural and Herbal Science
NA
MB

MinWoo Baek

kangwon national university
NA
SJ

SeMin Jang

kangwon national university
NA
ST

Shimeles Tilahun

kangwon national university, jimma university
NA
ST

SuHo Tae

kangwon national university
NA
Friday September 27, 2024 1:15pm - 1:25pm HST
Lehua Suite

1:15pm HST

VSF 2 - Effects of Chitosan and Ultraviolet A (UVA) Light on Postharvest of Blackcurrant Fruit
Friday September 27, 2024 1:15pm - 1:25pm HST
Blackcurrant (Ribes nigrum L.) is a small fruit known for its health benefits, but treatment effects on postharvest storage for fresh markets remains understudied compared to other berries, such as blueberry (Vaccinium spp.). This work aims to identify the effect of chitosan coating, ultraviolet a (UVA) light, and combined UVA-Chitosan treatments on blackcurrant postharvest storage. Physical (weight loss and firmness) and physiochemical analyses (soluble solid content, pH, citric acid content, and ascorbic acid content) were combined with microbial population quantification, phenolic compound characterization, and antioxidant capacity assessment. Samples were evaluated every three days of storage throughout this experiment. The results indicated that chitosan treatments have positive effects on reducing berry weight loss, maintaining berry firmness, and reducing mold populations. UVA influenced certain bioactive compounds, such as cyanidin-3-galactoside and rutin. The interaction effects from these two treatments were minimal. This study provides important information for blackcurrant postharvest storage and further small fruit storage work, considering both UVA and chitosan had differential beneficial effects on blackcurrant berries’ physical and chemical attributes.
Speakers
VR

Venkateswara Rao Kadium

Montana State University
Co-authors
AS

Andrej Svyantek

Montana State University
NA
AW

Aude Watrelot

Iowa State University
NA
ZM

Zachariah Miler

Montana State University
NA
ZW

Zhuoyu Wang

Montana State University
NA
Friday September 27, 2024 1:15pm - 1:25pm HST
South Pacific 3

1:15pm HST

CE 8 - Rapid Controlled Environment Propagation of Virus-Indexed Sweetpotato and Field Performance
Friday September 27, 2024 1:15pm - 1:30pm HST
Sweetpotato (Ipomoea batatas) production relies on clonal propagation of either sprouted storage roots grown in plant beds or from cuttings from greenhouse grown plants. In the USA, the Sweetpotato National Clean Plant Network Centers (SP-NCPN) provide virus-free planting stock of important cultivars for sweetpotato growers. However, most of the virus-indexed materials can be rapidly re-infected by one or more viruses within one growing season via insect vectors. Production of enough virus-indexed propagules is a major challenge and annually shortages exist. We have developed a controlled environment agriculture (CEA) technology that provides rapid propagation of virus-indexed propagules from SP-NCPN foundation stocks within 6 – 12 months. From a single virus-indexed in vitro plantlet, 500 rooted plants were obtained in 3 months compared to 3 plants via tissue culture micropropagation. Within 3 months the 500 rooted plants generated about 250,000 plants. Field performance (establishment and yield) of slips and rooted transplants from the CEA technology were compared with traditional plant bed derived slips. No significant differences were detected for establishment and canner and cull yield, whereas differences were found for total, marketable, jumbo, and US no. 1 yield. Our results offer a potential solution for providing growers a readily available source of virus-indexed propagule source that are comparable to field grown slips.
Speakers
PW

Phillip Wadl

USDA, ARS, U.S. Vegetable Laboratory
Co-authors
AG

Augustine Gubba

University of KwaZulu Natal
NA
BZ

Bazgha Zia

USDA, ARS, U.S. Vegetable Laboratory
NA
CA

Christie Almeyda

North Carolina State University
CC

Christopher Clark

Louisiana State University
NA
JC

John Coffey

USDA, ARS, U.S. Vegetable Laboratory
NA
JM

Joni McGuire

USDA, ARS, U.S. Vegetable Laboratory
NA
KL

Kai-Shu Ling

USDA, ARS, U.S. Vegetable Laboratory
NA
Friday September 27, 2024 1:15pm - 1:30pm HST
Nautilus 1

1:15pm HST

GG 4 - Development of Genetic Fingerprinting of Azalea Cultivars Using SSR Markers
Friday September 27, 2024 1:15pm - 1:30pm HST
Azaleas (Rhododendron spp.) are economically important ornamental flowering shrubs in landscapes around the world with thousands of cultivars representing many species of Rhododendron. Because azalea is an asexually propagated crop, potential discrepancies in plant identity may occur throughout the propagation pipeline, which can lead to mislabeling during propagation and commercialization processes. For example, the University of Minnesota (UMN) cultivar ‘Electric Lights Double Red’ is currently being propagated but flower morphology of the propagules differed from the original plant leading to uncertainty of propagule identity. Previous studies have identified DNA markers, specifically simple sequence repeats (SSRs), capable of differentiating azalea hybrid offspring from different species of the section Pentanthera. This study aims to leverage these previously developed SSR markers to authenticate the identity of breeding germplasm at the UMN and uniquely fingerprint other cultivars on the market. The evaluated azaleas pedigrees include up to 15 different species of deciduous azalea. Therefore, a total of 15 SSR markers that amplified fragments from several species of section Pentanthera were selected for this study. DNA was extracted from lyophilized leaf samples of 139 azalea cultivars using a Qiagen DNeasy Plant Pro Kit. Preliminary analysis of the azalea DNA using the selected SSR markers has identified the presence of 16 expected unique cultivars and 3 pairs of previously known duplicates. The outcome of this research will demonstrate the feasibility of providing azalea breeders, growers, and producers a marker-based system for assuring cultivar trueness-to-type and protection of intellectual property.
Speakers
SW

Seth Wannemuehler

University of Minnesota
Co-authors
DL

Diana Lopez Arias

University of Minnesota
NA
SH

Stan Hokanson

University of Minnesota
NA
SM

Steve McNamara

University of Minnesota
NA
Friday September 27, 2024 1:15pm - 1:30pm HST
Coral 1

1:15pm HST

HIH - Gauging 8th Graders’ Knowledge of Organic Agriculture Production and Labeling Practices
Friday September 27, 2024 1:15pm - 1:30pm HST
Pathways2Possibilities (P2P) is an interactive career expo for 8th graders in Mississippi. P2P encompasses 19 career pathways. The Agriculture, Food and Natural Resources Career Pathway focuses on supporting life by ensuring that we are responsibly managing our food production and natural resources. This pathway focuses on preparing students for careers in planning, implementing, producing, managing, processing and marketing of agricultural goods and services. Gulf Coast P2P hosted nearly 7,000 8th graders from 10 Coastal counties in the fall of 2023. from 10 South Mississippi counties. Delta P2P hosted nearly 2,000 8th graders from 10 Delta counties in the spring of 2024. At each event, a six question survey was presented to the students to determine their knowledge of organic agriculture and labeling practices. Questions were posed as Yes or No and were answered by Red (no) or Blue (yes) tickets in opaque boxes. Students were given temporary fruit and vegetable tattoos for participating. The six questions and respective YES responses (by location GC for Gulf Coast and D for Delta) were as follows: 1) Are genetically modified organisms allowed in organic products? GC: 31%, D: 48%; 2) Are organic farmers allowed to use natural methods for pest control? GC: 92%, D: 65%; 3) Are organic farms typically smaller than conventional farms? GC: 63%, D: 65%; 4) Is organic farming regulated by the U.S. government to ensure organic food labels accurately represent the product’s authenticity? GC: 63%, D: 58%; 5) Are organic products labeled with a special certification to help consumers identify them in stores? GC: 81%, D: 79%; and 6) Do certifies organic products have to be produced on a certified organic farm? GC: 53%, D: 62%. Nearly 600 students participated in the Gulf Coast survey and approximately 400 students participated in the Delta survey. Results are mixed as to how much knowledge students have about organic agriculture production and labeling.
Speakers
avatar for Christine Coker

Christine Coker

Professor or Urban Horticulture, Mississippi State University
Co-authors
BB

Brenton Breland

Mississippi State University
HW

Haley Williams

Mississippi State University
JR

Jenny Ryals

Mississippi State University
ME

Mike Ely

Mississippi State University
NA
PK

Patricia Knight

Mississippi State University
NA
Friday September 27, 2024 1:15pm - 1:30pm HST
South Pacific 1

1:15pm HST

VGBR 3 - Introgressing QTL from a Wild Relative to Improve Gummy Stem Blight Resistance in Watermelon
Friday September 27, 2024 1:15pm - 1:30pm HST
Watermelon (Citrullus lanatus) is an economically important horticultural crop known for its sweet red flesh and is a popular summer snack. The southeastern US is an important production region for watermelon, but the hot and humid weather is conducive for the development of fungal diseases. Gummy stem blight (GSB), caused by three species of Stagonosporopsis; S. citrulli, S. caricae and S. cucurbitacearum, is an important disease that can cause severe yield losses worldwide under these favorable conditions. Currently, no resistant cultivars are available for this disease and management depends on preventative fungicide spay programs. Host resistance has been previously identified in C. amarus, an inedible crop wild relative of watermelon. However, different Stagonosporopsis spp. isolates elicit different responses in different resistant host genotypes which complicated resistance breeding. To address these issues, we (i) developed a point-of-care assay that can differentiate S. citrulli from the other two species and (ii) introgressed resistance QTL from wild C. amarus into cultivated watermelon. A dipstick-based DNA extraction method was coupled with an S. citrulli specific loop-mediated isothermal amplification (LAMP) assay to detect as little as 1 pg of DNA with real time fluorescence quantification and endpoint colorimetric detection formats. To address host resistance, we developed high throughput KASP markers spanning the QTL regions, and used marker assisted backcrossing to introgress QTL into the cultivar Crimson Sweet. Eight BC2F3 intogression lines were evaluated in the field for resistance to GSB. Two of the lines showed high levels of resistance to GSB under field conditions. KASP assays were also developed for background selection for known domestication alleles to accelerate selection for fruit quality traits. The developed detection assays, KASP markers and introgression lines can contribute to accelerated breeding for host resistance and general breeding efforts for GSB in watermelon.
Speakers
CM

Cecilia McGregor

University of Georgia
NA
Co-authors
AB

Amelia Boettcher

University of Georgia
NA
JR

Jorge Reyes

University of Georgia
NA
SR

Samikshya Rijal

University of Georgia
NA
Friday September 27, 2024 1:15pm - 1:30pm HST
South Pacific 4

1:25pm HST

CITR - Assessment of Biomass and Carbon Storage of Satsuma Mandarin Trees in Jeju Island, Korea
Friday September 27, 2024 1:25pm - 1:35pm HST
In October 2020, the Republic of Korea set a landmark goal to achieve net zero emissions by 2050. However, the national greenhouse gas emission statistics did not account for carbon absorption by agricultural lands, including orchards, due to the absence of adequate calculation systems and data. Recognizing the significant role of photosynthesis in fruit trees like Citrus in carbon sequestration and climate change mitigation, this study aims to address this gap. We focused on developing allometric equations for estimating biomass and carbon stocks of citrus trees, particularly in orchards across Korea, with a case study on Jeju Island, a principal citrus cultivation area. Measurements of height, crown width, and the diameter of rootstock and trunks were conducted, observing an increase with tree age, though trunk diameter showed considerable variability. The study encompassed trees aged 5–45 years of the Satsuma Mandarin (Citrus unshiu Marc. cv. Miyagawa), a major citrus cultivar cultivated in Korea. Components including leaves, branches, trunks, and roots were harvested, dissected, fresh weighed, and oven-dried to develop dry to fresh weight ratios for dry biomass calculation. Allometric equations with trunk diameter as the sole independent variable were formulated for the Satsuma Mandarin tree. Furthermore, the total carbon content for trees aged 5–45 years was assessed through direct and destructive harvesting, revealing a carbon content range of 44.13 to 46.85% across different tree organs, with root carbon content increasing with age. This comprehensive study provides crucial insights into the biomass and potential carbon fixation capabilities of citrus trees, contributing significantly towards the accuracy of national carbon stock estimations. This work was carried out with the support of the Research Program for the National Institute of Horticultural
Speakers
JP

Jeesoo Park

Researcher, Citrus Research Institute, National Institute of Horticultural and Herbal Science
Co-authors
CW

Cheol Woo Choi

National Institute of Horticultural and Herbal Science
NA
DH

Dong Hoon Lee

National Institute of Horticultural and Herbal Science
DY

Dong Yong Lee

National Institute of Horticultural and Herbal Science
NA
SM

Suk Man Park

National Institute of Horticultural and Herbal Science
NA
YP

YoSup Park

National Institute of Horticultural and Herbal Science
NA
YE

Young Eel Moon

National Institute of Horticultural and Herbal Science
NA
Friday September 27, 2024 1:25pm - 1:35pm HST
Kahili

1:25pm HST

PH 3 - Development and Characterization of Bio-based Nanoparticle Coatings from Sweetpotato Peels
Friday September 27, 2024 1:25pm - 1:35pm HST
Bio-based nanoparticle coatings were developed using nanomaterials extracted from sweetpotato peels and combined with other biopolymers to reduce postharvest deterioration of sweetpotato roots and other fresh produce items. The sustainable coating materials applied as thin films to the surface of washed sweetpotato roots reduced postharvest deterioration, weight loss, and respiration rate, while maintaining root market quality. Chemical and physical characterization was made of the cellulose nanomaterials (CNMs), pectin, and phenolic compounds from ‘Beauregard’ sweet potato peel tissue. The peel contained 40.2% cellulose, 19.1 % lignin, 10.8% hemicellulose and 29.8% pectin. The extracted CNMs from the peel tissue showed a high degree of crystallinity, particularly for cellulose nanocrystals. The CNMs and pectin fractions formed stable water dispersions with strong shear thinning behavior suitable for coating application. The thin films formed by the CNMs and pectin fractions exhibited an entangled fiber network structure with significantly reduced water and gas permeability. Our results demonstrated the feasibility of using sweetpotato peel tissue as an integral component in a bio-based nanoparticle film coating.
Speakers
DP

David Picha

Louisiana State University Agricultural Center
Co-authors
QW

Qinglin Wu

LSU Agricultural Center
NA
RA

Ragab Abouzeid

School of Plant, Environmental and Soil Sciences
NA
Friday September 27, 2024 1:25pm - 1:35pm HST
Lehua Suite

1:25pm HST

VSF 2 - Biostimulants Did Not Influence Strawberry Yield but Increased Fruit Sugar Content
Friday September 27, 2024 1:25pm - 1:35pm HST
In the past few years, there has been an increased interest in the use of biostimulants for improved crop production. Biostimulants are products that can promote plant growth when applied in amounts so small that they do not provide much nutrition. These are composed of different organisms, compounds or plant extracts; they include beneficial fungi and bacteria, humic and fulvic acid, seaweed extracts, and protein hydrolysates. During the 2022-23 growing season we evaluated three different biostimulant products in annual hill strawberry plasticulture production. ‘Ruby June’ plants were transplanted on 24 Oct, 2022 on non-fumigated beds and were maintained as per grower standard practices. Treatments were as follows (i) no biostimulant (ii) preplant AminoSalmon (247 kg/ha) applied during bed making (3) plugs dipped for 20 seconds in TerraGrow Liquid (TGL, 3ml/38 L) prior to transplanting followed by a foliar spray and a drip application (1.5L/ha) at one, fourteen, and thirty days after transplanting, resuming monthly during spring; and (iv) EZ-GRO 16-0-0 (3.9 kg/ha) drip application 14 days after transplanting and every 14 days during fall, resuming during spring. All non-treatment irrigation valves were closed during treatment injection through the drip lines. Ripe fruit was harvested beginning 31 March and continued twice a week until 16 June. Harvested fruit was categorized into marketable and non-marketable yield by replicate and fruits were weighed for each category. Yields were cumulated for the season and expressed as g/plant for data analysis. For total yield and marketable yield, no treatment differences were found. Fruit size was estimated as g/fruit by weighing 10 marketable fruits weekly. Five marketable fruits were measured weekly for firmness using a texture analyzer then stored at -20 °C for later analysis of pH and total soluble solids (°Brix) using a digital refractometer. While fruit firmness and pH were not influenced by treatments, the application of both the amino salmon and EZ-GRO biostimulants significantly improved total soluble solids values compared to the untreated control.
Speakers
JS

Jayesh Samtani

Associate Professor, Virginia Tech
Co-authors
BA

Baker Aljawasim

Virginia Tech
NA
GP

Guillaume Pilot

Virginia Tech
NA
PR

Patricia Richardson

Virginia Tech
NA
Friday September 27, 2024 1:25pm - 1:35pm HST
South Pacific 3

1:29pm HST

MKEC - Marketing and Economics
Friday September 27, 2024 1:29pm - 2:00pm HST
Identifying the Ideal Combination of Strawberry Variety and Climate Control for Greenhouse Cultivation in Michigan -Amanda Jessica Da Silva
Economic impact of Winter Injuries on Golf Courses in North America - Chengyan Yue
Producing Sweet Potatoes to Manage Farm Income Risk in North Carolina - Godfrey Ejimakor


Friday September 27, 2024 1:29pm - 2:00pm HST
South Pacific 2

1:30pm HST

MKEC - Identifying the Ideal Combination of Strawberry Variety and Climate Control for Greenhouse Cultivation in Michigan
Friday September 27, 2024 1:30pm - 1:40pm HST
Strawberries are among the most popular fruits consumed in Michigan. However, Michigan's climate conditions hinder local production on a commercial scale. Outside of the summer period, production is only viable through controlled environment cultivation. Consequently, local demand relies on shipments from other U.S. producing regions, such as California and Florida, or imports mainly from Mexico. Given the delicate nature of this fruit, the long-distance supply chain can compromise the quality of the fruit, leading to substantial losses at retail and consumer levels. These factors drive the need to identify strategies to extend strawberries production season and empower a resilient regionalized supply chain. Our study aimed to optimize economic returns of greenhouse strawberry growers in Michigan using a bioeconomic modeling approach. Three strawberry varieties, namely Albion, Cabrillo, and Monterey, were grown in a greenhouse utilizing five different temperature treatments. The temperature treatments employed during the day and night cycles were set as 15/7° C, 10/18° C, 21/13° C, 24/16° C, and 27/19° C, respectively. Data was collected on productivity per plant and transplanted into a commercial grower scenario. The spatial-temporal bioeconomic model simulated the implementation of 15 hypothetical greenhouses, each covering an area of 1,000 m2, to accommodate one variety and one treatment at the time. Using a partial budget analysis, the research identified profitability capacity for greenhouse strawberry cultivation. From a costing perspective, the model considered the most important operating costs, including energy consumption by supplemental lighting and heating systems, labor requirements, materials (runners, fertigation, etc.), and growing space requirements. As for revenue, the model estimated potential revenues based on production capacity and market prices. By integrating these factors, the model provided estimates of the impacts of different combinations of strawberry varieties and treatment on fruit production. All three varieties had lower productive performance in the 15/7° C treatment, with Albion and Monterey only producing strawberries in weeks 8 and 9. The 24/16° C treatment showed the best productivity for all varieties, with Monterey achieving best economic results, followed by Cabrillo and lastly, Albion.
Speakers
avatar for Amanda Jessica Da Silva

Amanda Jessica Da Silva

Research Assistant, Michigan State University
Friday September 27, 2024 1:30pm - 1:40pm HST
South Pacific 2

1:30pm HST

CE 8 - Development of a pH Management Protocol for Strawberry Mother Plants Grown in Deep Water Culture
Friday September 27, 2024 1:30pm - 1:45pm HST
Maintaining a target pH range is important for root zone management and overall plant growth and quality. Commercial soilless substrates often contain liming amendments to increase initial substrate pH to between 5.5 and 6.2. Hydroponic nutrient solutions are less-well buffered than soilless substrates and can experience pH drift in the absence of frequent monitoring and adjustment. Hydroponic deep water culture (DWC) was explored for strawberry (Fragaria × ananassa) research studies, to more-easily collect root growth parameters and root samples for elemental analysis, compared to soilless substrate culture. However, an effective strategy for pH management needed to be developed. The objective of this study was to develop a protocol for growing strawberry mother plants hydroponically. First, three hydroponic systems (drip-irrigated coarse perlite, drip-irrigated sand, and DWC) were compared to a peat-based soilless substrate control. Plants received a modified strawberry nutrient solution (Yamazaki) at a nitrogen (N) concentration of 100 mg·L-1. Plants grew similarly across the four growing systems. Deep water culture provided the easiest access to clean roots; however, root zone pH decreased
Speakers
JB

Jennifer Boldt

Research Horticulturist, United States Department of Agriculture
Co-authors
EY

Erin Yafuso

United States Department of Agriculture
Friday September 27, 2024 1:30pm - 1:45pm HST
Nautilus 1

1:30pm HST

GG 4 - A Chromosome-Scale Haplotype-Resolved Reference Genome of Lantana camara and Insights into Unreduced Female Gamete Production
Friday September 27, 2024 1:30pm - 1:45pm HST
This comprehensive study unveils the first annotated, haplotype-resolved, chromosome-scale reference genome of Lantana camara, alongside insights into candidate genes for unreduced female gamete production through ovary transcriptome sequencing. L. camara, a native of the Caribbean, plays a dual role as a valued ornamental plant and a challenging invasive species. The absence of a high-quality genomic resource has previously limited the exploration of its ornamental and invasive characteristics. This work closes this gap by delivering a critical genomic resource for L. camara, essential for ornamental breeding programs and invasive species management. The genome of a diploid L. camara breeding line UF-T48 was assembled de novo, utilizing HiFi and Hi-C reads, achieving phased genome assemblies with a BUSCO score of 97.7% and LAI score of 19.37, indicating high quality. This assembly resolved all 22 chromosomes into pseudochromosomes, with an average length of 117 Mb, and annotated 83,775 protein-coding genes, laying a foundational step for Verbenaceae family genomic research. Simultaneously, this research delves into the plant’s reproductive biology, specifically targeting the mechanism of unreduced female gamete production, a trait that has played an important role in the evolution and spread of lantana, contributed to the plant’s invasiveness, and and complicated the development of sterile triploids. By aligning RNA-seq data to the reference genome, we identified differentially expressed genes associated with cell division and meiosis, crucial for understanding the genetic underpinnings of unreduced gamete production. These findings not only enhance the genetic comprehension of L. camara but also provide invaluable genomic resources for future genetic studies, conservation efforts, and breeding strategies aimed at producing non-invasive sterile cultivars. This pioneering genomic and transcriptomic analysis marks a significant leap forward in researchers’ ability to manipulate L. camara for both horticultural innovation and environmental management.
Speakers
BP

Brooks Parrish

University of Florida
Co-authors
ZD

Zhanao Deng

University of Florida
Friday September 27, 2024 1:30pm - 1:45pm HST
Coral 1

1:30pm HST

HIH - Growing Impact: Evaluating Global Investments in Fruit and Vegetable Production for Healthier Diets
Friday September 27, 2024 1:30pm - 1:45pm HST
Objective: The Horticulture Investment Study seeks to quantify and qualify public and private investments, alongside identifying challenges and opportunities in horticultural research and development, aimed at facilitating high-level policy engagement. This research is led by the Feed the Future Innovation Lab for Horticulture, in collaboration with the World Vegetable Center, the One CGIAR Initiative on Fruit and Vegetables for Sustainable Healthy Diets (FRESH), and various university partners. Background: Despite widespread recommendations to increase fruit and vegetable consumption—endorsed by 93% of Food-Based Dietary Guidelines—significant barriers remain. These include limited access, high costs, and entrenched dietary preferences, alongside inadequate global production that disproportionately impacts low-income and Global South populations. Addressing these issues is vital for enhancing nutrition and income, particularly through the empowerment of small-scale farmers in the Global South, where fruits and vegetables often represent women-managed crops. Methods: This study spans several countries including Cambodia, Philippines, Nepal, Sri Lanka, Benin, Ghana, Tanzania, Kenya, Guatemala, USA, and Germany. It employs a mixed-methods approach, beginning with a Delphi questionnaire distributed among key stakeholders from government, academia, international NGOs, and the private sector. Subsequent in-person workshops facilitate discussions on investment estimates and the dynamics of horticultural investments in each country. The inaugural workshop in Nairobi, Kenya, gathered 18 local experts who provided critical investment insights and validated the use of Delphi and Q methodologies for this study. Impact: The study aims to illuminate the economic and social impacts of investing in fruit and vegetable production, focusing on enhancing accessibility and affordability. It also addresses environmental considerations such as land use, aiming to support sustainable agricultural practices. By bridging gaps in horticultural investment, the study intends to foster supportive environments that enhance fruit and vegetable production and consumption, thus contributing to the Sustainable Development Goals. Conclusion: This study underscores the critical need for enhanced investment in horticulture to overcome systemic barriers to fruit and vegetable consumption, thereby improving global health and economic outcomes, especially for vulnerable populations in the Global South. The outcomes are expected to guide policy decisions and stimulate further research and development in the horticulture sector.
Speakers
EM

Erin McGuire

Director, University of California, Davis
Friday September 27, 2024 1:30pm - 1:45pm HST
South Pacific 1

1:30pm HST

VGBR 3 - Genome-wide association study reveals potential loci for powdery mildew resistance in the USDA core collection of Cucurb
Friday September 27, 2024 1:30pm - 1:45pm HST
Summer squash (Cucurbita pepo) is a significant vegetable crop in the United States with an annual value exceeding $216 million. The production of summer squash is significantly hindered by powdery mildew (PM), a fungal disease caused by Podosphaera xanthii. Management of PM relies on costly and routine application of fungicides. Moderate resistance to PM (designated PM0) in C. okechobeensis is widely deployed in commercial summer squash cultivars. However, it is important to expand the repertoire of alleles against PM in squash to complement and reduce the risk of PM0 resistance breakdown. In the current study, the USDA core collection of C. pepo (n= 207) was evaluated for PM resistance in Florida (greenhouse), New York (greenhouse), and Michigan (field) using a randomized complete block design across three reps, each with five plants. ‘Success PM’ (carrying PM0) and ‘Early Prolific’ Straightneck cultivars were used as resistant and susceptible checks, respectively. Pathogen inoculum was provided through naturally infected plants. At the 6th true-leaf stage, symptom severity data were collected on a scale of 0-100% based on visible pathogen sporulation on the surface of ‘top 4th leaf’, ‘bottom 4th leaf’, ‘stem above 4th leaf’, ‘stem below 4th leaf’, and ‘whole plant’. Across locations, ‘Success PM’ and ‘Early Prolific’ were consistently tolerant and susceptible, respectively. On the other hand, wide phenotypic variation was observed across the C. pepo core collection with accession 189 showing resistance across locations. The multi-location phenotype data was combined with genome-resequencing data (4 million SNPs) for the core collection to conduct a genome-wide association study using three statistical models (MLM, FarmCPU, and Blink). GWAS analysis for the FL dataset revealed significant genomic loci associated with PM resistance for ‘top 4th leaf’ (Chr 11 and 20), ‘stem above 4th leaf’ (Chr 4, 14 and 16), and ‘whole plant’ (Chr 13, 15, 18 and 20). Resistance loci for ‘top 4th leaf’ and ‘whole plant’ co-located on Chr 20, suggesting potential linkage/ pleiotropy for the two traits. For NY, significant hits for PM resistance were detected for the ‘top 4th leaf’ (FarmCPU: Chr 2, 4, 7, 13 and 19; Blink: Chr 3, 4, 5 and 19) and ‘bottom 4th leaf’ (Chr 6, 14 and 19). However, no significant GWAS hits were observed using MI data. The significant loci detected in this study will be validated and deployed in marker-assisted selection to improve PM resistance in squash.
Speakers
PS

Prerna Sabharwal

PhD Student, University of Florida
NA
Co-authors
CM

Carmen Medina-Mora

Michigan State Univ.
NA
CT

Charles Thomas Day

Cornell University
NA
CD

Christine D Smart

Cornell University
NA
GM

Geoffrey Meru

University of Florida
NA
GP

Gregory P Inzinna

Cornell University
NA
LI

Libby Indermaur

Cornell University
NA
MH

Mary Hausbeck

Michigan State University
NA
MM

Michael Mazourek

Cornell University
NA
Friday September 27, 2024 1:30pm - 1:45pm HST
South Pacific 4

1:35pm HST

CITR - Effect of Gamma Irradiation on Survival, Fruit Characteristic, and Thorn Length in Different Varieties of Citrus
Friday September 27, 2024 1:35pm - 1:45pm HST
In this study, we investigated the variety-dependent survival of citrus seedlings and analyzed the pomological characteristics of fruits and thorn lengths following irradiation with gamma rays. Scions from the seedlings of the following citrus varieties, ‘Yuzu’, ‘Noeulhyang’, ‘Sarahyang’, ‘Namgam’ (nucellar), and ‘Meiwakumquat’ irradiated with gamma rays at 0, 60, 80, and 100 Gy were grafted onto trifoliate orange. At 6 months after grafting, the survival rates of ‘Yuzu’ and ‘Noeulhyang’ exposed to 100 Gy were 49.5% and 34.8%, and that of ‘Sarahyang’ and ‘Namgam’ (nucellar) exposed to 80 Gy were 51.6% and 46.8%, respectively. ‘Meiwakumquat’ exhibited the lowest survival among the varieties used in this study. Therefore, we classified ‘Meiwakumquat’ as highly susceptible to gamma radiation; ‘Noeulhyang’, ‘Sarahyang’, and ‘Namgam’ (nucellar) as intermediately susceptible; and ‘Yuzu’ as the least susceptible. We assessed the effects of gamma radiation on the pomological traits in irradiated ‘Tambit1ho’ and ‘Yuzu’. Among the 72 irradiated ‘Tambit1ho’ seedlings, the average seed number (number of seeds per fruit) varied between 0 and 18.6, whereas that in the unirradiated seedlings was between 8 and 18. Among the irradiated seedlings, the average seed number was less than 1.0 in eight seedlings. In addition, we observed variations in weight, rind and segment hardness, and sugar and acid contents. The thorn length of the flush in unirradiated ‘Yuzu’ was between 1.3 and 6.0 cm, whereas that of flush in gamma-irradiated seedlings was between 0.1 and 6.1 cm. Among the irradiated ‘Yuzu’ seedlings, the thorn length was less than 0.1 cm in two seedlings.(This work was carried out with the support of the Research Program for the National Institute of Horticultural
Speakers
avatar for Dong-Hoon Lee

Dong-Hoon Lee

Senior Researcher, National Institute of Horticultural and Herbal Science
Co-authors
CW

Cheol Woo Choi

National Institute of Horticultural
NA
JP

Jeesoo Park

Citrus Research Institute, National Institute of Horticultural and Herbal Science
SH

Su Hyun Yun

National Institute of Horticultural
NA
SM

Suk Man Park

National Institute of Horticultural
NA
Friday September 27, 2024 1:35pm - 1:45pm HST
Kahili

1:35pm HST

VSF 2 - Updates on the Genome Database for Vaccinium (GDV): How GDV supports Vaccinium Research and Breeding
Friday September 27, 2024 1:35pm - 1:45pm HST
The Genome Database for Vaccinium (www.vaccinium.org) is a valuable resource for genomics, genetics, and breeding research related to blueberries, cranberries, bilberries, and lingonberries. It provides a wide range of genetic data, including genetic markers, linkage maps, and GWAS/QTL alongside genome data. GDV has the MapViewer tool to dynamically view genetic maps as well as genetic data associated with genomes and powerful search interfaces to query and download genetics data in table formats. For Vaccinium breeders, The Breeding Information Management System (BIMS) is a useful tool for storing, managing, archiving, and analyzing breeding data. Additionally, BIMS can be synchronized with the Field Book App to allow efficient phenotypic data collection and management. This poster will provide an update on new data and tools such as BIMS and MapViewer incorporated in GDV. We will demonstrate how these data and tools can be used for research and breeding activities.
Speakers
RA

Roohollah Abdolshahi

Auburn University
Co-authors
CC

ChunHuai Cheng

Washington State University
NA
DM

Dorrie Main

Washington State University
JY

Jing Yu

Washington State University
NA
JH

Jodi Humann

Washington State University
KB

Katheryn Buble

Washington State University
NA
NB

Nahla Bassil

USDA-ARS
NA
PZ

Ping Zheng

Washington State University
NA
SJ

Sook Jung

Washington State University
NA
SR

Sushan Ru

Auburn University
TL

Taein Lee

Washington State University
NA
Friday September 27, 2024 1:35pm - 1:45pm HST
South Pacific 3

1:40pm HST

MKEC - Economic impact of Winter Injuries on Golf Courses in North America
Friday September 27, 2024 1:40pm - 1:50pm HST
Golf courses in the northern regions of the United States and Canada experience occasional damage from winter stresses. This damage can sometimes be very severe, resulting in substantial financial impacts. Winter damage to turfgrass surfaces affects golf course finances in three primary ways: pre-winter maintenance costs, post-winter repair expenses, and revenue losses due to delayed openings. In 2022, a survey was conducted among golf course superintendents in the northern USA. and Canada. This survey collected data on the causes of winter injuries, the extent of damage across the golf course and various management practices employed. Preliminary results have shown that on average the annual costs incurred for preventing winter injuries were between $12,291 and $13,790 and the additional costs resulting from winter injuries ranged from $7,452 to $8,951 per golf course.
Speakers
CY

Chengyan Yue

University of Minnesota-Twin Cities (Minneapolis, MN)
Co-authors
DS

Doug Soldat

University of Wisconsin
NA
EW

Eric Watkins

University of Minnesota-Twin Cities (Minneapolis, MN)
NA
KF

Kevin Frank

Michigan State University
NA
MD

Michelle DaCosta

University of Massachusetts
NA
PK

Paul Koch

University of Wisconsin
NA
UP

Uma Parasuram

University of Minnesota
NA
Friday September 27, 2024 1:40pm - 1:50pm HST
South Pacific 2

1:45pm HST

CITR - Insights from a Citrus Breeding Program: Leveraging the Citrus Genome Database and Breeding Information Management System
Friday September 27, 2024 1:45pm - 1:55pm HST
Citrus is one of the most valuable fruit crops globally and Florida historically has been known to be the major state producing sweet oranges for juice. Continuous efforts to develop new scion and rootstock varieties have been on-going in the University of Florida Citrus Breeding Program since the 1980s. Over the years numerous phenotypic data sets including big data from image-based phenotyping and large genotypic data sets from advances in sequencing technology have been generated. Efficient tools for data collection and management of both phenotypic and genotypic information are needed. To facilitate citrus breeding in Florida and elsewhere, the Citrus Genome Database (CGD, www.citrusgenomedb.org) has developed a Breeding Information Management System (BIMS) to store, manage, and analyze the phenotype and genotype data of private breeding programs. BIMS is compatible with Field Book, an Android App that allows for collection of phenotype data in a digital notebook on a tablet or phone. As a participant of the 2022-funded SCRI-project ‘Advanced National Database Resources for Specialty Crop Research and Improvement’, the UFL Citrus Breeding Program has adopted BIMS. This poster demonstrates the value of moving to electronic data collection using Field Book and the web-based management system BIMS. The goal of the UF breeding program for this project is to work together with citrus breeding programs across the U.S. and provide training on how to use BIMS and Field Book as well as adapt these tools to meet the needs of citrus breeders.
Speakers
RT

Ronald Tapia

University of Florida/IFAS Citrus Research and Education Center
Co-authors
BE

Bryan Ellerbrock

Clemson University
NA
DM

Dorrie Main

Washington State University
FG

Frederick Gmitter

University of Florida/IFAS Citrus Research and Education Center
NA
JH

Jodi Humann

Washington State University
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
TR

Trevor Rife

Clemson University
NA
Friday September 27, 2024 1:45pm - 1:55pm HST
Kahili

1:45pm HST

CE 8 - Adjusting dissolved oxygen in nutrient solution for optimized kale and arugula growth in hydroponics
Friday September 27, 2024 1:45pm - 2:00pm HST
Dissolved oxygen (DO) level in hydroponic solution is an important factor affecting plant root development and water and nutrient uptake. However, precisely controlling the DO level in hydroponics has always been difficult due to the direct linkage of solution temperature and oxygen concentrations, especially under different aeration methods. Besides potentially controlling solution temperature, using liquid oxygen fertilization such as hydrogen peroxide (H2O2) has been shown to burst increase DO concentration in the solution, and ozonation, which is a sanitization treatment, has the potential to adjust DO level by supplying oxygen in nutrient solution. Our objective was to evaluate the effects of different DO levels and oxygenation strategies in a hydroponic system for the optimal growth of kale (Brassica oleracea) and arugula (Eruca vesicaria). In this study, we used ozone generators and hydrogen peroxide (H2O2) as a DO enrichment method in addition to the air pump-based aeration system to test the effects of different DO levels – low, medium, high as 6, 9, 12 mg/L, respectively – on kale ‘KX-1’ and ‘Red Russian’, and arugula ‘Astro’ and ‘Esmee’ grown in a deep water culture system. Treatment without using ozone generators or H2O2 was assigned as control. The study was arranged as a completely randomized design with three replications. DO and temperature probes were connected to a datalogger to trigger ozone generators and H2O2 injection using a relay once the DO levels were below the set thresholds. Weekly measurements were taken for plant height, leaf and anthocyanin chlorophyll content. The final harvest additionally measured leaf area, shoot and root biomass the leaf soluble solids content, titratable acidity, and leaf nutrient concentration. Plants grown under a high DO level had a higher root-to-shoot ratio, but the overall higher plant yield was achieved under the medium DO level. This system demonstrated that precise DO level control could be achieved using a sensor-based system.
Speakers
KQ

Kuan Qin

University of Georgia
Friday September 27, 2024 1:45pm - 2:00pm HST
Nautilus 1

1:45pm HST

GG 4 - Identification of Flowering Dogwood QTLs for Bract Color using a Pseudo-F2 Population
Friday September 27, 2024 1:45pm - 2:00pm HST
Flowering dogwoods (Cornus florida L.), known for their showy spring display and year-round appeal, are extensively planted as ornamental trees. In 2019, dogwoods ranked third in value for deciduous flowering trees in the U.S., generating more than $31 million in wholesale and retail sales. Tennessee is vital to this industry. The state leads the country in the number of dogwood plants sold, with almost double the number of trees sold as the next top producing state in the country. The showy bracts of dogwoods are modified leaves with a spectrum of color ranging from white to red, with many intermediate colors and patterns. Cornus florida ‘Cherokee Brave’ with deep pink bracts and ‘Appalachian Spring’ with creamy white bracts are two popular cultivars. Partially phased reference genomes have recently been assembled and annotated for these cultivars, ranging from 1,253 to 1,266 Mbp in length with 28,558 to 28,768 annotated protein coding genes. With these newly annotated genomes providing greater context, a QTL analysis was conducted using a pseudo-F2 population of ‘Cherokee Brave’ × ‘Appalachian Spring’ which segregates for bract color. Genotyping was completed using double-digest restriction-site associated DNA sequencing (ddRADseq) with PstI and MspI. With increasing demand for high-throughput phenotyping, six different phenotypic methods were utilized to determine which method was optimal for QTL detection. The phenotyping methods included: 1) manual characterization into binary classes (white or pink); 2) manual characterization into five classes (white, light blush, medium blush, pink, red); 3) colorimeter readings; 4) image analysis using full inflorescence; 5) image analysis using bracts detached from inflorescence; and 6) one bract per inflorescence. QTLs were identified using all phenotyping methods. The QTLs identified here will be used as the foundation for developing a marker assisted selection system for bract color in flowering dogwoods.
Speakers
TH

Trinity Hamm

University of Tennessee, Knoxville
Co-authors
DH

Denita Hadziabdic

University of Tennessee, Knoxville
NA
DS

DeWayne Shoemaker

University of Tennessee - Knoxville
NA
MN

Marcin Nowicki

University of Tennessee, Knoxville
NA
MS

Margaret Staton

University of Tennessee, Knoxville
NA
RT

Robert Trigiano

University of Tennessee, Knoxville
NA
SB

Sarah Boggess

University of Tennessee, Knoxville
NA
WK

William Klingeman

University of Tennessee, Knoxville
NA
Friday September 27, 2024 1:45pm - 2:00pm HST
Coral 1

1:45pm HST

VGBR 3 - BreedwithBIMS (Breeding Information Management System) for Crop Breeders
Friday September 27, 2024 1:45pm - 2:00pm HST
With the continuous development of new scientific technology and methodology, breeding programs are both producing and utilizing a large amount of big data. This requires efficient management systems to keep track of various types of data such as performance, pedigree, geographical and image-based data as well as genotype data. Access to integrated breeding data in a database enhances genetic understanding of important traits and maximizes the marker-assisted breeding utility by breeders. The Breeding Information Management System (BIMS) is a free, open-source, secure and online breeding management system which allows breeders to store, manage, archive, and analyze their private breeding program data that has been available in several crop databases. But what about the crops that do not have a database? We report the utility of a new BIMS website (www.breedwithbims.org) that allows any crop breeders can use BIMS. One of the key features of BIMS is that users can import new trait data via an Android App called Field Book as well as historical data via templates. Field Book app allows breeders to collect phenotype data with less possibility of transcription errors. BIMS is also BrAPI compliant so that breeders can send and receive data from other BrAPI compliant resources including the Field Book App. Potential for streamlining data collection and management for vegetable crops will be presented.
Speakers
avatar for Ksenija Gasic

Ksenija Gasic

Clemson University
Co-authors
CH

Chun Huai Cheng

Washington State University
NA
DM

Dorrie Main

Washington State University
JY

Jing Yu

Washington State University
NA
JH

Jodi Humann

Washington State University
MI

MIchael Itam

Clemson University
SJ

Sook Jung

Washington State University
NA
TL

Taein Lee

Washington State University
NA
Friday September 27, 2024 1:45pm - 2:00pm HST
South Pacific 4

1:50pm HST

MKEC - Producing Sweet Potatoes to Manage Farm Income Risk in North Carolina
Friday September 27, 2024 1:50pm - 2:00pm HST
The resilience of farmers and farm families are often threatened by the risk associated with farm income. One of the sources of farm income risk is the volatility or variability in crop yields. Climate change or crisis could amplify this risk thereby making farmers, their families and communities less resilient. One of the ways that farmers could manage farm income risk is to diversify their operations by adding crop enterprises. Enterprise diversification works best as an income risk management strategy if the returns from the crop that is being added is negatively correlated with the returns from the other crops. Understanding how the income from some crops or enterprises correlate with those other crops is a vital tool in using diversification as a risk management tool. We assess the suitability of producing sweet potatoes as a way to manage farm income risk through enterprise diversification. We identify major crops that are produced in North Carolina to include cotton, hay, peanuts, soybeans, flue cured tobacco, wheat, squash, strawberries, tomatoes and sweet potatoes. We then derive the annual revenues per acre for each crop as the product of the per acre yield and price per unit for each of the last 15 years. The correlation coefficients between the revenues per acre between sweet potatoes and each of the other crops are estimated. The correlation coefficients between sweet potatoes and the other crops range from -0.002 for squash, and 0.79 for hay. After squash, the next lowest correlation coefficient is between sweet potatoes and snap beans at 0.29 while that with peanuts is 0.47. These results indicate that farm operations in North Carolina that include sweet potatoes and squash could reduce farm revenue risk without substantially reducing the level of revenue.
Speakers
GE

Godfrey Ejimakor

North Carolina A
Friday September 27, 2024 1:50pm - 2:00pm HST
South Pacific 2

1:59pm HST

Local Food Systems (LOCSY)
Friday September 27, 2024 1:59pm - 4:00pm HST
Sustainable Small Plot Farming and Entrepreneurship Training Program - Alexis Howard
Edible Weeds for Sustainable Food Systems: Pilot studies with emphasis on purslane - Roland Ebel
Louisiana Harvest of the Month – Promoting Local Food and Food Literacy - Carl Motsenbocker
Enhancing Food Security and Sovereignty: A Case Study of the University of Connecticut Federally Recognized Tribes Extension Program - Shuresh Ghimire
Response of Leafy Edibles Grown on an Extensive Greenroof Compared to Conventional Field Production - Kaitlyn M Lamaster
Diverse Internships as an Opportunity to Engage Underrepresented Students Into Local Food Systems - Angel Cruz
Food Policy and Food Security - Sophia Darrow
An Urban Agriculture Green Roof Study: Cultivating Sustainable Local Food Sources - Julieta Sherk
Moderator
AC

Angel Cruz

North Carolina State University
Research Scholar at NC State University
Friday September 27, 2024 1:59pm - 4:00pm HST
South Pacific 1

1:59pm HST

1:59pm HST

Pomology 4 (POM 4)
Friday September 27, 2024 1:59pm - 4:00pm HST
Six -year Performance of Semi-dwarfing Peach Rootstocks From the NC-140 'Cresthaven' Trial in Western Colorado - Jeff Pieper
Nutritional Dynamics and Horticultural Performance of Peach Orchard in the United States in Response to Different Soil Amendment Programs. - Ayodeji Idowu
Influence of Low-, Medium-, and High-Chill Requirement Rootstocks on the Metabolomic Profile of Low-Chill Peaches - Jonathan Clavijo Herrera
Effects of plum tree architecture on canopy light environments and fruit quality - Lisa Tang
Does the Utah Model Still Work in Utah? Evaluation of Existing Phenological Models for Tart Cherry in a Changing Climate - Josette Moon
A Mobile Cartographer System to Measure Tree Growth Within Tart Cherry Orchards - Brent Black
Enhancing Uniformity in Tart Cherry Orchards Through Precision Management and Variable Rate Fertilization - Kurt Wedegaertner
Tree temperature prediction to improve chill accumulation estimation in cherry under climate change - Giulia Marino

Moderator
Friday September 27, 2024 1:59pm - 4:00pm HST
South Pacific 3

2:00pm HST

CE 8 - Developing Cardinal Temperatures for Leafy Green Growth and Development Parameters from Constant and Positive Day-Night Temperatures
Friday September 27, 2024 2:00pm - 2:15pm HST
In the evolving landscape of controlled environment agriculture (CEA), precise temperature management remains a pivotal factor in enhancing the growth, development, productivity, and quality of high-value leafy greens. Our research identifies the cardinal temperatures — base (Tb), optimum (Topt), and maximum (Tmax) — for red-leaf and green butterhead lettuce (Lactuca sativa), arugula (Eruca sativa), and kale (Brassica oleracea), comparing how both constant mean daily temperature (MDT) within a greenhouse and positive day-night temperature differences (DIF) in a growth chamber influence plant growth and development. In the greenhouse, we had a constant MDT of 8, 13, 18, 23, 28, and 33 °C under a photosynthetic photon flux density (PPFD) of 220 µmol∙m‒2∙s‒1 for 12 h∙d–1, while in the growth chamber we targeted the same MDTs with air day/night (12 h/12 h) set points of 11/5 °C, 16/10 °C, 21/15 °C, 26/20 °C, 31/25 °C, or 36/30 °C under a PPFD of 300 µmol∙m‒2∙s‒1. Both arugula and kale had greater biomass accumulation at lower Tb and Topt compared to lettuce, suggesting a propensity for growth under a cooler MDT. Specifically, the Topt for fresh mass accumulation was found to be at 24.7 °C for arugula, 22.9 °C for kale, and higher for lettuce cultivars 'Rex' and 'Rouxaï RZ' at 24.7 and 26.2 °C, respectively. We found that DIF exerted minimal influence on these crops, emphasizing the critical role of MDT in influencing their developmental outcomes. Additionally, our research provides insight into the impact of temperature on various physiological and morphological parameters, such as leaf unfolding rate, biomass accumulation, and susceptibility to physiological disorders such as bolting or tipburn. This study underscores the importance of precise temperature management in CEA, offering guidance for producers seeking to optimize energy use while maximizing crop yield and quality.
Speakers
ST

SEAN TARR

Michigan State University
Co-authors
RL

Roberto Lopez

Michigan State University
NA
Friday September 27, 2024 2:00pm - 2:15pm HST
Nautilus 1

2:00pm HST

GG 4 - Evaluation of Hibiscus cannabinus as an Alternative Fiber Crop for Florida: Identification of Valuable Traits and Germplasm for Cultivar Improvement
Friday September 27, 2024 2:00pm - 2:15pm HST
Hibiscus cannabinus, commonly referred to as Kenaf, is an annual warm-season plant that can thrive in the Southeastern United States. It serves as a vital source of natural fiber with diverse applications, such as biocomposites, paper pulp, textiles, industrial absorbents, animal bedding, and potting medium. A set of 86 accessions of Hibiscus cannabinus, acquired from USDA-GRIN, underwent evaluation in Central Florida for various parameters, including plant height, basal width, stem width 50 cm above the plant base, stalk fresh weight, stem fresh weight, stalk dry weight, leaf dry weight, bast weight, and core weight. Significant variations were observed among accessions for all the measured variables. Notably, stalk dry weight emerged as the key trait of interest, representing the plant portion with desirable fibers for various applications. The top Duncan grouping for stalk dry weight comprised eight accessions: PI 329191 (18-85), PI 639889 (18-157) known as "Whitten," PI 270111 (18-55) known as "G-32," PI 603071 (18-152) known as "Dowling," PI 638930 (18-154) known as "74200 I4," PI 638932 (18-156) known as "Yue 74-3," PI 270106 (18-50) known as "G-14," and PI 468077 (18-137). Out of the 86 USDA-GRIN accessions examined, these eight have been identified as the top-performing choices for field production in Central Florida. Furthermore, these selected accessions are deemed desirable parents for future cultivar improvement endeavors, aiming to develop enhanced cultivars of Hibiscus cannabinus specifically tailored for production in Central Florida.
Speakers
JW

James Webb

University of Florida
Co-authors
CA

Conner Austin

University of Florida
Friday September 27, 2024 2:00pm - 2:15pm HST
Coral 1

2:00pm HST

LOCSY - Edible Weeds for Sustainable Food Systems: Pilot studies with emphasis on purslane
Friday September 27, 2024 2:00pm - 2:15pm HST
An interdisciplinary team at Montana State University (MSU) has initiated a project to evaluate the cultivation, commercialization, processing, and food use of the associated plant agrobiodiversity, or “edible weeds.” The project involves different food system stakeholders and targets underutilized/neglected edible plant species on local farms. In four pilot studies in Montana, conducted in 2023, we emphasized common purslane (Portulaca oleracea) as a model edible weed due to its abundance in local horticultural systems, its relatively limited competition with crops, and rich data on nutritional properties. Annual common purslane exhibits a versatile habitat range, including gardens, crop fields, and orchards. The hermaphroditic plant is self-fertile, flowers from June to September, thrives in well-drained soils, and requires direct sunlight. While considered a weed across the US, purslane is cultivated in diverse countries due to its culinary and medicinal attributes. Stems and leaves are consumed raw and cooked, in salads, sauces, or soups. Purslane also serves as a thickening agent due to mucilaginous properties. The succulent leaves are abundant sources of omega-3 fatty acids. In our first study, we monitored edible weeds on 3 farms in Bozeman, Montana. Purslane exhibited its highest occurrence in emerging carrot crops and on freshly tilled beds. In our second study, we sampled 35 weed species on 7 vegetable farms across Montana. Purslane had a relative abundance of 6.52% and was found in kale, onions, carrots, and bean plots. In our third study, we conducted a sensory test among attendees of the MSU Presidential Luncheon. We presented 3 purslane products: compound herb butter, cornbread muffin, and blueberry compote. 42 attendees responded to an online survey on their overall quality, flavor, and texture. All products were perceived positively with a rate of 7.5 to 7.7 on a Likert-scale from 1 (dislike extremely) to 9 (like extremely). 52% of participants had never thought about eating edible weeds. Finally, for 2 days, a Mexican restaurant in Bozeman, offered 2 traditional dishes, purslane with pork in green salsa and chicken in red salsa. Participants responded to an online and paper survey with a questionnaire similar to the one for the luncheon. Out of 53 validated responses, dishes were assessed with an average of 8.17 (chicken) and 8.53 (pork) on a 1-9 Likert-scale. Over 90% of respondents considered purslane an appropriate vegetable for these dishes. Our findings indicate potential of selectively weeding purslane from vegetable production systems and consumer interest in the vegetable.
Speakers
avatar for Roland Ebel

Roland Ebel

Research Associate, Montana State University
Roland Ebel has dedicated his professional life to the facilitation and the production of sustainable food. He counts with a PhD in Organic Farming, granted by the University of Natural Resources and Life Sciences Vienna. The thesis project was done in Gran Canaria, Spain, and dealt... Read More →
Co-authors
EK

Emma Kubinski

Montana State University
NA
FM

Fabian Menalled

Montana State University
NA
WK

Wan-Yuan Kuo

Montana State University
NA
Friday September 27, 2024 2:00pm - 2:15pm HST
South Pacific 1

2:00pm HST

PNM 3 - Optimizing Nitrogen Fertilization for Evergreen Blueberry (Vaccinium corymbosum interspecific hybrids) in Florida
Friday September 27, 2024 2:00pm - 2:15pm HST
There are multiple ways to grow highbush blueberries (Vaccinium corymbosum interspecific hybrids). In Florida, an evergreen growing system was developed to overcome unpredictable chill hour accumulation. In this system, blueberry bushes retain their leaves throughout the year when fertilized appropriately. Deciduous blueberry farms typically skip fertilization during the fall and winter months. On the other hand, evergreen blueberry farms require winter fertilization to ensure healthy foliage. Therefore, fertilizer recommendations for deciduous blueberry are not applicable to evergreen blueberry. This research aims to optimize nitrogen fertilization for evergreen southern highbush blueberry plants in Florida. ‘Arcadia’ and ‘Sentinel’ southern highbush blueberry plants were grown in a high tunnel in Citra, FL. Plants were fertigated according to commercial practices, except for nitrogen (N). Nitrogen was applied manually as ammonium sulfate at 5 different annual rates (in Kg/ha): 5.6, 83.4, 138.9, 222.3, and 444.6. Plant size, leaf area index, leaf N concentration, fruit yield, and fruit quality were measured during the 2023 and 2024 seasons. Nitrogen fertilization rates affected plant growth during the spring and summer, but not during the fall and winter. Higher N fertilization rates led to higher leaf area index, a proxy for leaf retention. Plants in the lowest N fertilization treatment were not evergreen, as they dropped nearly all their leaves in the winter. Leaf N concentrations of plants in treatments 83.4 Kg/ha or higher were above the reference levels for N deficiency. Linear plateau regressions were used to identify optimum fertilization rates. During the 2023 season, ‘Arcadia’ exhibited a yield plateau, but ‘Sentinel’ did not, suggesting that N fertilization has cultivar-specific effects. All fruit harvested exhibited commercial quality in terms of soluble solids. However, fruit in the lowest fertilization rate was softer and more acidic than fruit in all other treatments. These results suggest that multi-year studies with multiple varieties are necessary to identify N fertilization rates that maximize agricultural productivity while minimizing fertilizer inputs.
Speakers
GN

Gerardo Nunez

University of Florida
Co-authors
LG

Lauren Goldsby

University of Florida
NA
Friday September 27, 2024 2:00pm - 2:15pm HST
Lehua Suite

2:00pm HST

POM 4 - Six -year Performance of Semi-dwarfing Peach Rootstocks From the NC-140 'Cresthaven' Trial in Western Colorado
Friday September 27, 2024 2:00pm - 2:15pm HST
Eight rootstock cultivars were planted in 2017 as part of the NC-140 semi-dwarfing peach [Prunus persica (L.) Batsch] rootstock trial. The eight rootstock cultivars were budded to ‘Cresthaven’ and examined for their potential use in Western Colorado high density production systems. Listed in order of declining vigor the rootstocks included ‘Guardian®’, ‘Rootpac® 20’, ‘Lovell’, ‘ControllerTM 8’, ‘ControllerTM 6’, ‘Rootpac® 40’, ‘ControllerTM 7’, and ‘MP-29’. One rootstock, ‘ControllerTM 7’, was unable to perform in alkaline soils, showing extreme iron chlorosis and diminutive fruit size. Deemed unsuitable for use in Colorado, this rootstock was removed from analysis in the 3rd leaf. Six years of data showed that all remaining rootstocks, except ‘MP-29,’ had vigor profiles within 14% of ‘Lovell’, a known standard, making them attractive candidates for use in high density production. The two ‘Rootpac®’ rootstocks performed contrary to previous reports. ‘Rootpac® 20’ was the second most vigorous and ‘Rootpac® 40’ was the third least vigorous, slightly larger than ‘ControllerTM 6’. Additional physiological traits showing distinct differences between the rootstocks were yield, proleptic shoot formation, light interception, fruit size, and internal fruit quality. In the six years since planting there have been three harvests. Cumulative yield showed a strong linear relationship to vigor (TCSA). ‘ControllerTM 6’ had early precocity and high yields given its vigor class. Observance of gummosis was also positively associated with vigor. Both vigor and proleptic shoot formation manipulated the canopy light environment. ‘ControllerTM’ series rootstocks had increased proleptic shoot formation. Vigor-limiting rootstocks had increased light availability in the canopy leading to enhanced dry matter content and soluble solid concentration. Cumulative fruit size and weight showed ‘Rootpac® 20’ had the heaviest, and ‘ControllerTM 6’ the largest, fruit size. ‘MP-29’, the most dwarfing rootstock produced smaller fruit on average; however, fruit size was still commercially acceptable.
Speakers
JP

Jeff Pieper

Colorado State University
Co-authors
Friday September 27, 2024 2:00pm - 2:15pm HST
South Pacific 3

2:00pm HST

Workshop: Designing Consumer Horticulture Programs: State-wide Impact, County Specific Needs, Locally Diverse Participants
Friday September 27, 2024 2:00pm - 4:00pm HST
The goal of this workshop is to bring together consumer horticulture stakeholders working to create sustainable, enjoyable, healthy communities and to identify methods for achieving greater impact through effective process of program identification, development, and measurement. Those active in any role of developing and delivering consumer horticulture programs, including Master Gardener activities, are encouraged to attend. Creating impactful programming in this field is influenced by stakeholders with varied goals and resources, content specificity due to planting zones and habitat, and the audience’s diverse economic and social demographics. To achieve greater success, more effort must be invested in the process of goal setting, stakeholder participation, resource allocation, collaborative implementation, and measurement. However, drilling down from a state-wide vision through regional, county-based resources and content to be delivered to locally diverse residents requires effective processes and creative thinking. Through discussion, we will identify internal roadblocks to success and learn the creative ways our peers may have overcome similar situations.

Workshop attendees are assigned a number 1, 2 or 3 upon entry. For the first 5 minutes, the participants of the workshop complete one of three pre-workshop surveys
1 - Your Role in the Field of Consumer Horticulture
2 – Success Indicators of Impactful Consumer Horticulture Programs
3 – Identifying Appropriate Consumer Horticulture Programs). For the next 10 minutes, the participants will discuss the definition of the term ‘consumer horticulture’ to ensure clarity of purpose.
This will include an activity generating a list of potential stakeholders and types of programs to illustrate the complexity of the field and to further clarify national, state and local needs. The presenters will then spend 40 minutes sharing a specific example of a layered, complex program development system including their success indicators and impediments. The moderator will represent the flow of information through the system, illustrating the places, sometimes obvious and others unexpected, where the process stops or gains momentum. Presenters represent state, regional and local roles. Workshop participants spend the next 40 minutes in round-robin breakout groups, rotating through 4 topics. The topics are in the form of questions regarding different aspects of goal setting, stakeholder development, program identification and success measurement. Each break out group will be moderated by one of the presenters. The group will reassemble for 20 minutes to discuss the outcome of their work. Notes will be taken for distribution to the group. For the last 5 minutes the group will take different versions of the pre-workshop test as a post-workshop assessment.

Consumer horticulture is a critical topic for national to local level stakeholders invested in developing healthy, sustainable communities. There are few focus areas that affect the quality of life of communities to the degree that this field can. Successful consumer horticulture efforts result in economic development opportunities, increased food access, strengthened social structures, mental health support and more. Yet, while the importance of integrating gardening on individual and community levels is widely recognized, efforts to develop and conduct programs to achieve consumer horticulture goals are difficult to establish and have little data supporting impact. To achieve greater success, more effort must be invested in the process of goal setting, stakeholder participation, resource allocation, collaborative implementation, and measurement. There is a plethora of information available about specific consumer horticulture activities such as community gardens, schoolyard habitats and classes for homeowners. However, before beginning activity development, the field would be strengthened by discussion of the purpose of these programs and the process of delivering information effectively to the intended audience.

The goal of this workshop is to bring together professionals in the field of consumer horticulture from different geographic and organizational systems and, through guided discussion, identify methods for achieving greater impact through effective program identification, development, and measurement.


Coordinator(s)
  • Ruth Carll, Rutgers, Agriculture and Natural Resources, New Brunswick, NEW JERSEY, United States
Speaker/Participant(s)
  • Peter Nitzsche, Rutgers NJAES Cooperative Extension, United States
    Member of Panel (10 mins)
    Summary: Peter Nitzche, Director of the Clifford E. & Melda C. Snyder Research and Extension Farm at Rutgers Center for Sustainable Agriculture, and the Department Head for the Rutgers Cooperative Extension of Morris County represents the perspective of county-level program leadership. He leads events, programming and task force teams while overseeing extension staff that implement programs. He also actively conducts research and contributes to departmental goals.
  • Belinda Chester, Rutgers, Rutgers Cooperative Extension, New Brunswick, New Jersey, United States
    Panel Member (10 mins)
    Summary: Belinda Chester is a Horticulture Program Associate II and Master Gardener Coordinator with the Rutgers Cooperative Extension of Atlantic County. On this panel, she represents the challenges of creating and managing programs with regional and local specificity. She must meet goals of both Rutgers and her county. Her constituents are urban, suburban and rural, including a large farming demographic. This large county also presents a geographic challenge.
  • Ruth Carll, Rutgers, Agriculture and Natural Resources, New Brunswick, NEW JERSEY, United States
    Panel Member (10 mins)
    Summary: Ruth Carll, State Coordinator of Consumer Horticulture and Master Gardener Program, leads Rutgers statewide consumer horticulture activities, ensuring that the University’s goals are achieved. Her research involves impact studies designed to guide program development and determine success. Ruth will represent state-level goal setting and program oversight.
  • Lisa Chiariello, Rutgers, Rutgers Cooperative Extension, New Brunswick, New Jersey, United States
    Panel Member (10 mins)
    Summary: Lisa Chiariello is an Agriculture and Natural Resources Program Associate II with the Rutgers Cooperative Extension of Sussex County. On this panel, she represents the work of developing training for volunteers who deliver programs that meet statewide goals with specific local content and activities.


Friday September 27, 2024 2:00pm - 4:00pm HST
Coral 2

2:14pm HST

Ornamentals/Landscape and Turf 3 (O/LT 3)
Friday September 27, 2024 2:14pm - 3:30pm HST
Seedling Zoysiagrass Response to Fluazifop-butyl and Trifloxysulfuron-methyl With the Safener Metcamifen - Hannah Wright-Smith
Influence of Demethylation Inhibiting Fungicides on Creeping Bentgrass Putting Greens - Wendell Hutchens
Endophytic N Fixing Bacteria Isolated From Warm-season Turfgrasses and Common Lawn Weeds - Andrea F Arevalo Alvarenga
Mowing Mediated Root Radial Transport of Lead in Cynodon dactylon (L.) Persoon - Xinyi Cai
Cool-season Turfgrass Biomass and Ecosystem CO2 Flux as Affected by Fertilization and Irrigation - Ruying Wang
The 2023 Arkansas Diamond Plant Evaluation Trials - Anthony Bowden
Moderator
HW

Hannah Wright-Smith

Extension Weed Specialist, University of Arkansas
Friday September 27, 2024 2:14pm - 3:30pm HST
South Pacific 2

2:14pm HST

Fruit Breeding 2 (FRBR 2)
Friday September 27, 2024 2:14pm - 4:15pm HST
A Century of Pear Breeding at the USDA - Christopher Gottschalk
Differential Thermal Analysis of Cold Hardiness in Interspecific Hybrid Grapevine for Breeding Applications - Douglas Vines
Ovary and Fruit Shape Variation Associated with Novel ClSUN25-26-27a Alleles in Watermelon - Samuel Josiah
Linking Cultivar Evaluations – Phenology, Metabolomics, Consumer Preferences, and Postharvest Handling of ‘Glenn’ Mango - Jonathan H Crane
Evaluation of Small Fruit Germplasm at the North Willamette Research and Extension Center - Patrick Jones
Developing a Genomic Framework for Selection of Fruit Attributes in Cold Climate Interspecific Grapes (Vitis Spp.) - Venkateswara Rao Kadium
U.S. Peach Production and Breeding Overview - Chunxian Chen
Introduction of modern tools to the University of Arkansas System Division of Agriculture Fruit Breeding Program - Carmen A. Johns
Moderator
JH

Jonathan H Crane

University of Florida, TREC
Friday September 27, 2024 2:14pm - 4:15pm HST
Kahili

2:15pm HST

FRBR 2 - A Century of Pear Breeding at the USDA
Friday September 27, 2024 2:15pm - 2:30pm HST
The U.S. Department of Agriculture (USDA) Agriculture Research Service (ARS) has operated a European pear (Pyrus communis) scion breeding program for over a century. The breeding program started in the early 1900s by Merton B. Waite in the Washington D.C. area with the primary objective to develop host resistance to fire blight, a devastating disease caused by Erwinia amylovora. The USDA pear breeding program has continued this effort throughout its history, spanning over six generations of breeders and two cooperative research programs in Michigan and Ohio. The program has released ten named pear varieties, with the first one, 'Waite,' being released in 1938 and the most recent, 'Bell,' in 2022. In this presentation, we discuss the program's history by detailing each generation of breeder(s) aims, their parental selection, and releases. In addition, we present corrected pedigrees for important breeding lines and the releases. Lastly, we present the current objectives of the program, the pedigree complexity of newly generated populations, and the overall success of the program’s primary breeding goal – fire blight resistance.
Speakers
CG

Christopher Gottschalk

USDA ARS
During his Ph.D. studies, Dr. Gottschalk studied the molecular mechanisms that control flowering in apple as they relate to seasonal bloom times and biennial/alternate bearing in diverse apple germplasm, from wild species to cultivated varieties. Moreover, he investigated plant growth... Read More →
Friday September 27, 2024 2:15pm - 2:30pm HST
Kahili

2:15pm HST

LOCSY - Louisiana Harvest of the Month – Promoting Local Food and Food Literacy
Friday September 27, 2024 2:15pm - 2:30pm HST
The Louisiana Harvest of the Month (HOM) is program that is intended to introduce locally grown food such as fruit and vegetables one time per month to schools. The program started as a pilot program in 2015 in three schools in Louisiana and expanded statewide in 2017. The HOM program is currently in 720 schools around the state and is also used by other programs such as Louisiana 4H. The HOM program highlights a local food item designated by schools with monthly materials such as HOM posters, activity sheets, coloring pages, recipes, sample newsletters, taste test guide and “I tried it stickers,” classroom activities and lessons linked to state standards, all available free of charge. There are 21 HOM items currently available to participants with a majority of the HOM items locally available fruits and vegetables, along with rice, and several proteins (crawfish, catfish, shrimp). The newest additions to the HOM portfolio of resources are short (12 to 14 minute) videos produced by Louisiana Public Broadcasting that are targeted to elementary school children. The videos highlight farmers and fishers on location for each HOM and also provide a section in the use of the local product in the kitchen and demonstrate recipes. There are currently 18 HOM videos and their popularity is demonstrated by some having been accessed over ten thousand times on YouTube and Facebook. Data from the HOM program will be presented including data on the use of the program and program analytics.
Speakers
CM

Carl Motsenbocker

Professor, Executive Director Louisiana Farm to School Program, Louisiana State University
Dr. Carl Motsenbocker is a professor of horticulture and sustainable agriculture at Louisiana State University. Motsenbocker is Executive Director of the Louisiana Farm to School Program and teaches Organic Gardening, Sustainable Agriculture and Vegetable Crops at LSU. Motsenbocker... Read More →
Co-authors
CH

Celeste H. Finney

Louisiana State University Agricultural Center
NA
CB

Crystal Besse

Louisiana State University Agricultural Center
NA
JA

Jacey A. Wesley

Louisiana State University Agricultural Center
NA
TB

Tyne Bankester

Louisiana State University Agricultural Center
NA
Friday September 27, 2024 2:15pm - 2:30pm HST
South Pacific 1

2:15pm HST

O/LT 3 - Seedling Zoysiagrass Response to Fluazifop-butyl and Trifloxysulfuron-methyl With the Safener Metcamifen
Friday September 27, 2024 2:15pm - 2:30pm HST
Managing grassy weeds in turfgrass can be challenging. In 2023 a new formulation of trifloxysulfuron-methyl containing the safener metcamifen, Recognition® Herbicide, was commercially available for use in established zoysiagrass. When applied as a mixture, this product safens zoysiagrass from the effects of the graminicide fluazifop-butyl (Fusilade® II Herbicide), allowing for higher application rates of fluazifop-butyl to manage difficult to control grass weeds such as bermudagrass. Previous research has demonstrated acceptable response following this herbicide mixture when applied to established zoysiagrass, however no information is available evaluating seedling zoysiagrass response to these herbicides. Experiments were conducted at the Milo J. Schult Agricultural Research and Extension Center in Fayetteville, AR and the Southwest Research and Extension Center in Hope, AR in 2023 to evaluate seedling zoysiagrass injury from applications of fluazifop-butyl and trifloxysulfuron-methyl with metcamifen applied at two different rates. “Zenith” zoysiagrass was seeded in June and August in Fayetteville and Hope, respectively, with herbicide applications made 2-and 4-weeks after emergence. Similar response was observed from both 2- and 4- week after emergence herbicide application timings. When applied as a mixture to seedling zoysiagrass, treatments of fluazifop-butyl plus trifloxysulfuron-methyl with metcamifen resulted in a maximum of 20% visual injury 1-week after treatment. However, seedling recovery was observed at subsequent ratings with
Speakers
HW

Hannah Wright-Smith

Extension Weed Specialist, University of Arkansas
Co-authors
DN

David Nistler

University of Arkansas
NA
JM

John McCalla

University of Arkansas
NA
LT

Lane Tredway

Syngenta
NA
MD

Michael D Richardson

University of Arkansas
NA
Friday September 27, 2024 2:15pm - 2:30pm HST
South Pacific 2

2:15pm HST

PNM 3 -The Effects of Nutrient Management on Yield in Cut-and-Come-Again Kale Production.
Friday September 27, 2024 2:15pm - 2:30pm HST
Cut-and-come-again, or repeat harvesting, is a practice in which a single planting of greens is harvested on multiple occasions. This is a common practice among small-scale, urban, and home producers in which the outermost leaves are removed, leaving the growing center of the plant intact enabling multiple harvests without compromising plant health. As this practice is not common among large-scale and commercial producers, there are currently no research-based fertilizer recommendations for cut-and-come-again greens. General guidance simply suggests continued, nitrogen-heavy fertilizer applications to ensure repeated harvests. This type of guidance is not easy to follow for beginners or for growers looking to improve their cut-and-come-again yields. An experiment was designed to examine eight different fertilizer application strategies to determine which provided better growth and nutritional quality in later kale harvests while limiting nutrient leaching. Fertilizer applications for the cut-and-come-again treatments (CC) ranged from an initial fertilizer application matching local nutrient recommendations, to repeated applications either the initial complete application or a nitrogen side dressing at every third, every other, or at each harvest. A single harvest control (ODB) was also harvested at the baby stage at each CC harvest. At each harvest, total and marketable yield were measured and crop quality for marketability was assessed per the USDA guidelines for kale and greens. There were more issues with slow growth, slow regrowth, and missing harvests for pots in the fall than the spring, and more issues in 2023 than in 2022. Some issues were directly related to significant caterpillar damage in the fall of 2023 which also affected the marketability of the leaves harvested. The expected dose response to fertilizer treatment was not observed in any growing season of the two years of the study completed so far. While some differences in yield between treatments were observed, these were predominantly between the ODB control and CC treatments, but not among CC treatments. The expected drop in yield with successive harvests was also not consistently observed in CC treatments. The CC treatment receiving only the initial fertilizer application exhibited a drop in yield with successive harvests in only two of the four growing seasons. Further examination of the fate of nutrients in the leaf material, soil and leachate from the experiment should explain these unexpected results and provide more clarity on an optimal fertilizer treatment.
Speakers
LW

Leigh Whittinghill

The Connecticut Agricultural Expeirment Station
Friday September 27, 2024 2:15pm - 2:30pm HST
Lehua Suite

2:15pm HST

POM 4 - Nutritional Dynamics and Horticultural Performance of Peach Orchard in the United States in Response to Different Soil Amendment Programs.
Friday September 27, 2024 2:15pm - 2:30pm HST
Compost, mulch and manures have been reported as a potential substitute for synthetic fertilizer in fruit orchards, can improve soil health as well as increase the sustainability of orchard systems. In this study, we compared two rates (10 tons/acre as compost 1x and 20tons/acre as compost 2x) of pre-plant incorporation of food waste compost (FWC) and growers’ standard rate of inorganic/chemical fertilizer (control) of a replanted and virgin peach orchards in South Carolina. Measurement includes soil health indicators such as soil nutritional status and macronutrient dynamics, yield, and fruit quality (specifically on the incidence of diseases and physiological disorders). We hypothesized that the pre-plant incorporation of organic matter with subsequent topical application would improve soil moisture and nutrient availability, increase yield, and enhance the quality of marketable fruits. Higher cation exchange capacity and buffering capacity was recorded in soil treated with FWC than in the control treatment. In the replanted orchard, the 2x treatment resulted in improving soil health indicators such as SOM, cation exchange capacity, phosphorus, soil infiltration, and soil moisture, but not in the virgin orchard compared to the control treatment. Soil extractable P was higher in the FWC treatment as compared to the control treatment, while the soil extractable K ranges from high to excessive K across all treatments. No significant difference between the yields from both orchards. However, we observed numerical differences in the yields of the 2x treatment compared to the 1x and control treatments. Our results show that the yearly application of compost provides the orchard’s nutritional requirement, increases yield, and lower disease pressure in both orchards compared to the control treatments.
Speakers
avatar for Ayodeji Idowu

Ayodeji Idowu

Graduate Research & Teaching Assistant, Clemson University
I am an adept third-year Ph.D. student working on improving soil health and ecosystem conservation through rigorous enhancement of soil organic matter and strategic soil nutrient management for agricultural and environmental sustainability. To achieve this, I am testing different... Read More →
Co-authors
GS

Guido Schnabel

Clemson University
NA
JC

Juan Carlos Melgar

Clemson University
NA
Friday September 27, 2024 2:15pm - 2:30pm HST
South Pacific 3

2:29pm HST

Growth Chambers and Controlled Environments 9 (CE 9)
Friday September 27, 2024 2:29pm - 4:00pm HST
Light Intensity Regulates the Interactive Effects between Far-red light and Temperature on Lettuce Growth, Morphology, Photosynthesis, and Secondary Metabolite - Sangjun Jeong
Lighting Around the Clock: Greenhouse Production with 24h Lighting - Jason Lanoue
Explore a Cost-friendly Way for Plant Nitrogen Stress Identification - Ping Yu
Optimization of Irrigation Based on Substrate Type for Tomato Production in the Dutch Bucket Hydroponic System - Milon Chowdhury
The Secondary Metabolite Production and Growth Responses of Cannabis to Thigmomorphogenesis in a Controlled Environment - Jose Franco Da Cunha Leme Filho
Simulated Climate-change-related Environmental Stressors Can Alter the Yield and Metabolomics of Tomato - Marlo Vandiver
Moderator
PY

Ping Yu

University of Georgia
Friday September 27, 2024 2:29pm - 4:00pm HST
Nautilus 1

2:29pm HST

Teaching Methods (TCHG)
Friday September 27, 2024 2:29pm - 4:00pm HST
Cultural IPM: Developing a Bilingual Landscaping Basics Booklet - Hannah Wooten
Learning Outcomes in Floral Design - Melinda Knuth
Mentor-Mentee Perspectives And Experiences In A Graduate Scientific Communications Course - Kent Kobayaski
Student Engagement and Learning: Evaluating the Effectiveness of Digital Discussion Tools - Remi Ham
Training the Next Generation of Leaders to Facilitate Successful and Resilient Urban Food Systems - Eleni Pliakoni
Students’ Knowledge of Landscape Sustainability, Soil Quality and Climate Change Across Experiential Learning Courses in Agriculture - I I N Handayani
Evaluating In-person and Online Video Teaching Methods to Introduce Landscape Equipment Operation and Safety - Levi Dreiling
Evaluating Student Understanding of Plant Physiological Processes After Class Presentations - Levi Dreiling
Development of an Agricultural Biotechnology Core Capstone Course - Adrienne Kleintop
Moderator
avatar for Remi Ham

Remi Ham

Assistant Teaching Professor, North Carolina State University
Remi HamAsst Teaching Professor and Distance Education CoordinatorKilgore Hall NA919-515-5373raham@ncsu.eduRemi’s body of work ranges from city planning, university planning, and project management. Her recent work has focused on designing edible teaching gardens and developing an environmental curriculum for K-12 schools. Additionally, Remi has focused on reducing food insecurity through com... Read More →
Friday September 27, 2024 2:29pm - 4:00pm HST
South Pacific 4

2:29pm HST

Genetics and Germplasm 5 (GG 5)
Friday September 27, 2024 2:29pm - 4:15pm HST
Breeding for Photoperiod Insensitive and Indeterminate Flowering Habit in Pigeonpea - Diego Viteri
Breeding for Improved Tomato Flavor - Denise Tieman
Genome-Wide Association Study Identifies Key SNPs Associated with Mineral Element Accumulation in Spinach (Spinacia oleracea) - haizheng xiong
Comparative Analyses of Tissue-Specific Transcriptome Responses to Salt Stress in Lettuce Roots and Leaves - Modan Das
QTL Mapping Of Horticulturally Important Plant Architectural Traits In Cucumber (Cucumis sativus L.) - Thi Nguyen
Screening Sweetpotato Germplasm for Resistance to Meloidogyne incognita - Phillip Wadl
Variation for Non-Acclimated and Acclimated Heat Tolerance Among Potato Germplasm: Indication of Separate Genetic Control - Jiwan Palta

Moderator
PW

Phillip Wadl

USDA, ARS, U.S. Vegetable Laboratory
Friday September 27, 2024 2:29pm - 4:15pm HST
Coral 1

2:30pm HST

TCHG - Cultural IPM: Developing a Bilingual Landscaping Basics Booklet
Friday September 27, 2024 2:30pm - 2:40pm HST
The USDA NIFA has funds for Extension that support more complex projects than typical programs. Since 2021, a multi-county Extension team has developed a UF/IFAS Bookstore publication titled “Basics of Landscaping in Florida, Conceptos Básicos de Paisajismo en Florida”. This pocket-sized, waterproof guide enables multi-lingual landscape teams to effectively communicate essential landscaping best management practices (BMPs). These BMPs promote long term landscape resilience while reducing reliance on chemical inputs. The environmental horticulture industry in Florida is worth over $10 billion annually, employs over 100,000 people, of which, 33% identify as Hispanic/Latino origin. Most horticulture jobs are focused on landscaping for aesthetics which leads to reactionary pest management focused on quick chemical solutions rather than long term economic, environmental, and social sustainability. In Florida, the use of pesticides and fertilizers requires training and professional licensure, yet chemical control and fertilization represent only a fraction of landscape integrated pest management (IPM). Cultural IPM, on the other hand, offers a key advantage: it allows for effective pest management while significantly reducing pesticide use. However, not all industry professionals require a license to perform their duties, and thus, many lack adequate training on the basics of IPM and BMPs. While quality training programs do exist, they may be cost prohibitive or too advanced for landscape professionals early in their careers or for employees performing basic tasks that fall within cultural IPM foundations. Research shows that people typically add more information and overlook subtractive approaches that may actually improve outcomes (Adams, et. al, 2021). The approach to teaching landscape basics is rooted in age old wisdom, from Occam’s Razor, Einstein’s famous quote, “Everything should be made as simple as possible, but not simpler”, and Lockheed Martin’s “Keep It Simple, Stupid (KISS)” methodologies. Thus, a more basic bilingual training on landscape best practices and IPM was needed and developed as part of the USDA, NIFA Award No. 2021-70006-35560. This booklet uses heuristic techniques designed to effectively communicate fundamental cultural IPM principles to a broader audience in English and Spanish, avoiding intricate and technical facets of horticulture. The team will disseminate booklets to clientele in 2024 and subsequently offer them for sale in the UF/IFAS Bookstore. This presentation will focus on simplifying horticultural science educational technologies, making them accessible, actionable, and agreeable for Floridians working with landscapes. Funding options, considerations, and experiences developing bilingual training materials will also be shared.
Speakers Co-authors
MP

Morgan Pinkerton

UF/IFAS Extension Seminole County
TM

Tina McIntyre

UF/IFAS
NA
Friday September 27, 2024 2:30pm - 2:40pm HST
South Pacific 4

2:30pm HST

CE 9 - Light Intensity Regulates the Interactive Effects between Far-red light and Temperature on Lettuce Growth, Morphology, Photosynthesis, and Secondary Metabolite
Friday September 27, 2024 2:30pm - 2:45pm HST
Phytochromes (PHYs) play a dual role in sensing light spectral quality and temperature. PHYs can interconvert between their active and inactive forms upon absorption of red and far-red light (Photoconversion). In addition, the active form can be converted to the inactive form in a temperature-dependent manner (Thermal Reversion). Our recent research found that while far-red (FR; 700-800 nm) light promoted leaf expansion and biomass of lettuce (Lactuca sativa) ‘Rex’ under cooler temperatures (20-24 °C), it reduced plant biomass and leaf area under warm temperature (28 °C). Considering that PHY activity would be driven mainly by photoconversion, not thermal reversion, under higher light intensity (HL), we hypothesized that the magnitude of the interaction between FR light and temperature on plant growth and morphology decreases with increasing light intensity. Lettuce ‘Rex’ was grown under three temperature regimes (20, 24, and 28 oC) x two spectral treatments [0 and 20% of FR light in total photon flux density (TPFD; 400-800 nm)] x two light intensities [150 (lower light intensity; LL) and 300 (HL) μmol·m-2·s- 1 of TPFD]. Our results showed that the effects of FR light on leaf expansion and stem elongation depended on temperature under LL. Specifically, FR light significantly promotes leaf expansion under cooler temperatures (20 oC), while decreasing total leaf area under warmer temperatures (24 and 28 oC). However, the magnitude of the interactive effects between FR light and temperature on plant morphology decreased under HL, leading to a consistent increase in total leaf area by FR light under HL. Similarly, FR light promoted plant growth under HL regardless of temperature, while reducing plant biomass under warm temperature under LL. Crop yield was primarily dependent on photon capture rather than photosynthetic efficiency per unit leaf area. FR light generally decreased the production of secondary metabolites (e.g., phenolics and flavonoids), while warm temperature and HL treatments increased the production of secondary metabolites. We concluded that the interactive effects between FR light and temperature on plant growth and morphology are further dependent on light intensity. The combination of FR light, warm temperature, and HL could maximize crop yield without reducing nutritional quality in terms of antioxidant capacity.
Speakers Co-authors
GN

Genhua Niu

Texas A
SZ

Shuyang Zhen

Texas A
NA
Friday September 27, 2024 2:30pm - 2:45pm HST
Nautilus 1

2:30pm HST

FRBR 2 - Differential Thermal Analysis of Cold Hardiness in Interspecific Hybrid Grapevine for Breeding Applications
Friday September 27, 2024 2:30pm - 2:45pm HST
Interspecific hybrid grapevine cultivars have been developed to expand grape cultivation into cold-climate areas. Cold weather events can lead to bud death and trunk injury which reduce yields and can result in plant death. Phenotyping cold hardiness is challenging, and developing a standardized phenotypic protocol would enable efficient evaluation of University of Minnesota grape breeding germplasm. The objective of this study is to utilize differential thermal analysis as an assay to quantify the low temperature exotherm response of grapevine buds. We phenotyped 28 varieties and advanced breeding selections from October 10th, 2023 through March 20th, 2024. Commercial cultivars (e.g. Marquette, Itasca, Frontenac) and breeding selections (wine grape, table grape, and rootstocks) were sampled weekly or bi-weekly based on availability of plant material. Differences in acclimation and deacclimation patterns between time points were observed in the low temperature exotherm readings, indicating that there may be differences in the genetic mechanisms for cold hardy responses. After the coldest day of the season, January 14, 2024, which had a low of -23°C, the temperature at which 50% of the buds would die, or LT50, for ‘Marquette’, ‘Itasca’, and ‘Frontenac’ were -29.7 °C, -30.9 °C, and -30.5 °C, which is consistent with field observations. The LT50s were rated at lower temperatures than the ambient air temperature, thus all genotypes were able to survive the weather conditions for this cold event. Future analysis aims to utilize K-means cluster analysis to determine groups that differ in responses to winter fluctuations in temperature and to determine the genetic controls for these responses.
Speakers
DV

Douglas Vines

University of Minnesota
Co-authors
MC

Matthew Clark

University of Minnesota
NA
SL

Soon Li Teh

University of Minnesota
NA
Friday September 27, 2024 2:30pm - 2:45pm HST
Kahili

2:30pm HST

GG 5 - Breeding for Photoperiod Insensitive and Indeterminate Flowering Habit in Pigeonpea
Friday September 27, 2024 2:30pm - 2:45pm HST
Pigeonpea [Cajanus cajan (L.) Mill.] is an important legume consumed in the Caribbean basin. Cultivars with indeterminate flowering habit have sensitivity to the photoperiod in Puerto Rico. The objectives of this research were to: (1) develop two breeding lines with indeterminate flowering habit that can be planted year-round, and (2) evaluate their agronomic performance. IIPG-7 and IIPG-11 breeding lines, derived from the bi-parental cross ‘ICPL 86012’/‘Guerrero’, were developed by pedigree and bulk breeding methods. Both breeding lines, their parents, and cultivars checks were tested in field trials in Isabela and Lajas, Puerto Rico in 2022 and 2023. IIPG-7 and IIPG-11 were early genotypes that initiated flowering between 73-84 days after planting (dap), and reached harvesting maturity at 121-127 dap compared with indeterminate cultivars ‘Ariel’, ‘Blanco Yauco’, ‘Kaki’, ‘Pinto Berrocales’, and ‘Super Pinto’ that initiated flowering between 91 to 102 dap and reached maturity at 138-148 dap. These cultivars had seed yield values over 1,000 kg/ha while IIPG-7 and IIPG-11 produced between 721 to 1,010 kg/ha under short day conditions in both locations. In contrast, IIPG-7 and IIPG-11 were the only indeterminate genotypes that initiated flowering between 42-88 dap, reached maturity between 88-172 dap, and seed yields varied from 626 to 2,449 kg/ha under long day conditions in Isabela and Lajas. These new breeding lines can be used to develop pigeonpea cultivars with insensitivity to the photoperiod.
Speakers
DV

Diego Viteri

University of Puerto Rico at Mayagüez
Co-authors
AL

Angela Linares Ramirez

University of Puerto Rico
Friday September 27, 2024 2:30pm - 2:45pm HST
Coral 1

2:30pm HST

LOCSY - Enhancing Food Security and Sovereignty: A Case Study of the University of Connecticut Federally Recognized Tribes Extension Program
Friday September 27, 2024 2:30pm - 2:45pm HST
The development of the University of Connecticut (UConn) Federally Recognized Tribes Extension Program (FRTEP) was a response to the need to enhance food security and sovereignty within the Mashantucket Pequot Tribal Nation (MPTN), while also reducing rates of obesity and Type II diabetes as the Tribal community faced food insecurity, alongside alarming rates of health disparities compared to their white counterparts. The program aimed to bolster agricultural capacity on Tribal lands, provide workforce development for Tribal members, and deliver health and nutrition education. Through extensive consultations with Tribal leaders and members, UConn FRTEP tailored programs in agriculture, workforce development, youth engagement, and health education. Since the initiation of the program in 2017 to 2023, Extension educators provided comprehensive training on vegetable and fruit production, integrated pest management, and business planning. Additionally, nutrition workshops, fitness classes, and virtual cooking sessions were conducted, fostering community engagement. Tribal youths engaged in educational activities and field trips designed to enhance agricultural literacy and healthy eating behaviors. To ensure sustainability, youths also participated in “train the trainer” opportunities. Project evaluations included resource inventories, focus groups, and pre/post-program surveys to measure immediate outcomes as well as broader impacts and community perceptions. The establishment of a farm that included hydroponic greenhouses, shipping-container farming, in addition to growing an array of vegetables and fruits on 5 acres by 2023 improved food security and sovereignty within MPTN. The farm produced tomatoes, lettuce, summer squash, winter squash, cucumbers, watermelon, chard, broccoli, potatoes, beans, herbs, and strawberries, supporting food distribution programs reaching 15% (180 members) of the Tribal population in 2022 and 2023. Additionally, in the same period, 30 diabetic patients received prescribed fresh produce from the farm. After completing nutritional education lessons (seven 1-hour long) in 2022, survey results indicated notable improvements among youth participants (n = 17): 60% showed enhanced ability in identifying active children, 50% improved recognition of fruits and dairy foods, and 44% exhibited better proficiency in identifying healthy snacks. Overall, the health of the tribal members improved through the consumption of fresh nutritious food, an increase in the number of tribal members practicing healthy eating habits, and exercise learned through training. The success of the project led to the creation of the MPTN Department of Agriculture. UConn FRTEP significantly strengthened university-tribal relations, exemplifying fruitful collaboration, boosting food security, economics, and health. This model partnership promotes sustainable development, empowering Indigenous communities, fostering resilience, and self-reliance.
Speakers
SG

Shuresh Ghimire

University of Connecticut
NA
Co-authors
EB

Erica Benvenuti

University of Connecticut
NA
JB

Joseph Bonelli

University of Connecticut
NA
MP

Michael Puglisi

University of Connecticut
NA
RR

Robert Ricard

University of Connecticut
NA
ST

Sara Tomis

University of Connecticut
NA
Friday September 27, 2024 2:30pm - 2:45pm HST
South Pacific 1

2:30pm HST

O/LT 3 - Influence of Demethylation Inhibiting Fungicides on Creeping Bentgrass Putting Greens
Friday September 27, 2024 2:30pm - 2:45pm HST
Demethylation inhibiting (DMI) fungicides are frequently applied to turfgrasses for suppression of many common fungal diseases in turfgrass. However, certain DMI fungicides cause phytotoxic effects to turfgrasses, particularly creeping bentgrass (Agrostis stolonifera L.), during the heat of the summer. A study was conducted in Fayetteville, AR in the summer of 2023 to determine the effects of nine DMI fungicides (flutriafol, mefentrifluconazole, metconazole, myclobutanil, propiconazole, prothioconazole, tebuconazole, triadimefon, and triticonazole) compared to a nontreated control on a ‘Pure Eclipse’ creeping bentgrass putting green. All treatments were applied a total of six times at the highest labeled rate at biweekly intervals beginning on 23 Jun 2023 and ending on 1 Sep 2023. A CO2-pressurized backpack sprayer was used to deliver the treatments in a carrier volume of 814 L ha-1. Plots were assessed weekly for percent phytotoxicity (0-100%). Additionally, beginning on 27 Jul 2023, clippings were collected, dried, and weighed weekly until 24 Aug 2023. Data were averaged across all rating dates, subjected to analysis of variance, and means were separated using a Student’s t-test (p < 0.05). Propiconazole caused ≥ 36.7% more phytotoxicity than any other treatment. The only other fungicide treatments that caused greater phytotoxicity than the nontreated control were myclobutanil and triadimefon. Myclobutanil, propiconazole, and triadimefon were also the only treatments to increase clipping weights compared to the nontreated control. These data suggest that many DMI fungicides do not cause phytotoxic effects on creeping bentgrass putting greens during the summer with the exception of myclobutanil, propiconazole, and triadimefon.
Speakers
WH

Wendell Hutchens

Assistant Professor of Turfgrass Science, University of Arkansas
Wendell Hutchens, PhD is an assistant professor of turfgrass science in the Horticulture Department at the University of Arkansas. His main areas of expertise are turfgrass pathology and precision management of turfgrass pests using emerging technologies. His research program is centered... Read More →
Co-authors
JA

Jessica Anders

University of Arkansas
NA
KG

Koa Grabar

University of Hawaii at Manoa
NA
MB

Michael Battaglia

University of Arkansas
NA
Friday September 27, 2024 2:30pm - 2:45pm HST
South Pacific 2

2:30pm HST

PNM 3 - Growth Responses of Hydroponic Vegetable Transplants to Nutrient Solution Concentrations Made with Food Waste Liquid Ana
Friday September 27, 2024 2:30pm - 2:45pm HST
Food waste liquid anaerobic digestates (FWLAD) have received much public attention for its potential as an organic fertilizer source as they are rich in mineral elements. However, FWLAD can contain high salinity and high NH4 concentration, and thus, the optimum application rates need to be determined to deliver required plant nutrients without excessive salt and NH4 level. The objective of this study was to evaluate the effects of nutrient solution concentration made from FWLAD on the growth of leafy vegetable seedlings. The seeds of lettuce (Lactuca sativa) ‘Rex’, ‘Muir’, and ‘Roxy’, Swiss chard (Beta vulgaris subsp. vulgaris) ‘Rhubarb’, bok choy (Brassica rapa subsp. chinensis) ‘Mei Qing Choi’, and kale (Brassica oleracea var. sabellica) ‘White Russian’ were sown in rockwool plug and grown at 22 °C under sole-source LED lighting with an 18-h photoperiod at a photosynthetic photon flux density of 200 µmol∙m-2∙s-1. After germination, the seedlings were sub-irrigated with nutrient solution made with either crude or processed FWLAD at electrical conductivities (ECs) of 1, 2, 3, or 4 dS·m–1. Four weeks after treatment, when using crude FWLAD, shoot fresh mass of three lettuce cultivars decreased by 76-92% as EC increased from 1 to 4 dS·m–1. In contrast, with processed FWLAD, lettuce ‘Adriana’ and ‘Roxy’ showed 68-1080% greater shoot fresh mass at an EC of 2 dS·m–1 compared to an ECs of 1, 3, or 4 dS·m–1. Shoot fresh mass of lettuce ‘Muir’ at an EC of 2 dS·m–1 was similar with that at an EC of 1 dS·m–1 but 380-516% greater than those at ECs of 3 or 4 dS·m–1. In lettuce, the EC of FWLAD had similar effects on leaf area as it did on shoot fresh mass, but it had minimal effects on leaf number, relative chlorophyll concentration, and shoot dry mass. In kale, Swiss chard, and bok choy, the EC of FWLAD had little effects on plant growth attributes. Our results suggest that leafy vegetable seedlings vary in their responses to nutrient solution concentrations derived from FWLAD, with lettuce exhibiting greater sensitivity than Swiss chard, bok choy, and kale. In lettuce, lower concentrations of FWLAD (at an EC ≤2 dS·m–1) increased shoot fresh mass.
Speakers
EW

Emily Webb

Arizona State University
NA
Co-authors
YP

Yujin Park

Arizona State University
ZC

Zhihao Chen

Arizona State University
NA
Friday September 27, 2024 2:30pm - 2:45pm HST
Lehua Suite

2:30pm HST

POM 4 - Influence of Low-, Medium-, and High-Chill Requirement Rootstocks on the Metabolomic Profile of Low-Chill Peaches
Friday September 27, 2024 2:30pm - 2:45pm HST
Rootstocks are widely used for commercial orchard establishments throughout the world, as they facilitate scion adaptation to challenging edaphic and environmental conditions, as well as mitigate the impact of pests and diseases. Furthermore, rootstocks may influence physiological, biochemical, or phenological processes in the scion. Nevertheless, little is known about the influence of rootstocks on metabolomic profiles of Prunus scions, particularly in low-chill cultivars. This study aimed to determine the influence of rootstocks with varied chilling requirements on the metabolomic profiles of low-chill peaches. Scion ‘UFSun’ was grafted on low-(Flordaguard), medium-(P-22), and high-(MP-29, Guardian, and Nemaguard) chill requirement rootstocks, and grown in a greenhouse in Gainesville, Florida. Vegetative tissue samples were collected for extraction of metabolites. Untargeted compounds were analyzed using an Orbitrap Fusion Tribrid mass spectrometer system, interfaced with an automated A VanquishTM UHPLC system, and a total of 152 metabolites were detected. Potential differences in metabolomes associated with the rootstocks were analyzed by performing a partial least square–discriminant analysis (PLS-DA), although it was not possible to determine group differences when comparing all treatments. An orthogonal PLS-DA approach supported by permutational MANOVA test was implemented for paired comparison of plants grafted on Flordaguard (rootstock recommended for commercial production in Florida) vs. all other rootstocks, and differences were observed for all comparisons. For further confirmation of these results, and determination of the metabolites potentially differentially expressed due to rootstock influence, the Empirical Bayesian Analysis of Microarrays (EBAM) approach was implemented, as adjusted for analysis of metabolites in MetaboAnalyst 6.0. A total of 85, 52, 0, and 61 metabolites were dimmed as potentially differentially expressed when comparing trees grafted on Flordaguard vs. P-22, MP-29, Guardian, and Nemaguard, respectively. Most of these metabolites may be flavonoids, phenylpropanoids, and polyketides. According to our observations, low-, medium-, and high-chill rootstocks can influence the metabolomic profile of low-chill scions.
Speakers
JC

Jonathan Clavijo Herrera

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
LR

Lorenzo Rossi

University of Florida
Friday September 27, 2024 2:30pm - 2:45pm HST
South Pacific 3

2:40pm HST

TCHG - Learning Outcomes in Floral Design
Friday September 27, 2024 2:40pm - 2:50pm HST
Learning objectives are put into place to measure student conceptualization in classroom activities. However, how effective are these learning outcomes in individualized student activities? Our research will explore how well students expressed learning concepts through in-class floral design construction. The target group is the students in HS 275 Floral Design. To study student understanding, we analyzed each week’s learning objectives by evaluating each student's submitted floral design project photograph. This was done through analyzing our review comments and student reflections of their final project. We will discuss the results of our study about applying teaching strategies that promote conceptualization that can potentially be applied broadly in higher education courses.
Speakers
MK

Melinda Knuth

North Carolina State University
Co-authors
JS

Julieta Sherk

NC State University , professor
Julieta Trevino Sherk is a distinguished Professor and professional landscape architect known for her expertise in teaching and community design. At North Carolina State University (NCSU) since 2003, she holds a position in the College of Agriculture and Life Sciences within the Department... Read More →
Friday September 27, 2024 2:40pm - 2:50pm HST
South Pacific 4

2:45pm HST

CE 9 - Lighting Around the Clock: Greenhouse Production with 24h Lighting
Friday September 27, 2024 2:45pm - 3:00pm HST
Photoperiod extension in controlled environment agriculture - including the use of 24h continuous light - can be used to reduce light fixture and electricity costs in regions with lower night electricity rates. However, many plant species develop photoperiodic injury characterized by leaf chlorosis and yield reduction at a critical species-specific photoperiod threshold. Here we will discuss the response of different plant species to continuous lighting strategies. We will first challenge the conventional notion that dark adapted chlorophyll fluorescence (Fv/Fm) measurements are the most appropriate when assessing photoperiodic injury. We provide evidence that light adapted (φPSII) measurements allow for a more in-depth understanding of the light capture process at photosystem II. Through RNA-sequencing in tomato, we determined that the use of a dynamic 24h lighting treatment (i.e., red light during the day and blue light during the night) lead to normal gene expression of chlorophyll a/b binding (CAB) proteins. However when tomato plants were grown under a static continuous lighting strategy (i.e., red blue lighting for 24h) at the same daily light integral, gene expression of CAB proteins were drastically reduced, resulting in chlorosis and yield reduction. In comparison to tomatoes, cucumbers tend to be more tolerant to long photoperiods and therefore continuous lighting can have an immediate impact in commercial production. Initial results in cucumbers show that a continuous lighting strategy can decrease the lighting electricity costs by 26% and greenhouse gas emissions by 38.9% per unit of produce compared to a 16h control treatment. Using the knowledge gained throughout our studies, we propose a lighting strategy which gamifies the electricity market to further reduce costs and greenhouse gas emissions.
Speakers
JL

Jason Lanoue

Agriculture
Co-authors
QD

Quade Digweed

Agriculture
NA
XH

Xiuming Hao

Agriculture
NA
Friday September 27, 2024 2:45pm - 3:00pm HST
Nautilus 1

2:45pm HST

FRBR 2 - Ovary and Fruit Shape Variation Associated with Novel ClSUN25-26-27a Alleles in Watermelon
Friday September 27, 2024 2:45pm - 3:00pm HST
The genetic mechanisms controlling fruit morphology in watermelon is not fully understood. Only one candidate gene, ClSUN25-26-27a (Cla011257), has been identified as a significant contributor to the ovary and fruit shape. ClSUN25-26-27a is a member of the SUN gene family, which has been extensively studied in relation to fruit morphology in tomatoes. In tomato, the effect on fruit shape facilitated by this gene is detectable during the early stages of fruit development, with the cell patterns established pre-anthesis. In watermelon, three alleles of ClSUN25-26-27a are known to be associated with ovary and fruit shape variation: the wild-type, a SNP, and a 159bp deletion in the 3rd exon. This study aims to determine the effect of the novel allelic variation for ClSUN25-26-27a on ovary and fruit shape. Four novel alleles have been identified and sequenced in the coding region of ClSUN25-26-27a across three Citrullus species. Marker assisted backcrossing was used to introgress the different alleles into a common genetic background. The NILs were phenotyped in the field to determine the effect of the novel alleles on ovary and fruit shape. Ovary length and width were measured four days pre-enthesis, at anthesis, and four days post-anthesis and used to calculate the ovary shape index (OSI). Mature fruit was also phenotyped using Tomato Analyzer. One of the novel alleles was significantly associated with ovary and fruit shape. These findings contribute to the understanding of the important SUN gene family and the genetic mechanisms contributing to watermelon fruit shape. Future research will determine the gene expression patterns of the different alleles and the effect of the alleles on the cell number or cell size in watermelon.
Speakers
SJ

Samuel Josiah

University of Georgia
Co-authors
CM

Cecilia McGregor

University of Georgia
Friday September 27, 2024 2:45pm - 3:00pm HST
Kahili

2:45pm HST

GG 5 - Breeding for Improved Tomato Flavor
Friday September 27, 2024 2:45pm - 3:00pm HST
Consumers are dissatisfied with the flavor of modern commercial tomatoes; however, modern tomato varieties have many desirable agronomic traits such as shelf life, disease resistance and yield. The flavor deficiency in modern tomatoes is due to a cumulative loss of superior alleles affecting flavor volatiles while breeding for other traits. The lack of breeder focus on the consumer is largely due to the genetic complexity of the tomato flavor phenotype as well as a lack of a simple assay that can define consumer preferences. Tomato flavor is a result of interactions between sugars, acids and aroma volatiles, with volatile compounds giving the tomato fruit its characteristic aroma and flavor. We have quantified 68 flavor biochemicals in over 700 tomato varieties, including modern, heirloom and ancestral tomato accessions. Over 160 of these varieties were evaluated by a large consumer panel for fruit flavor quality traits including overall liking. Genome Wide Association Studies (GWAS) identified genetic loci associated with altered levels of acids, sugars and aroma volatiles. We have used marker-assisted breeding to introgress loci associated with flavor biochemical levels from heirloom varieties into modern tomato varieties. Introduction of seven flavor loci affecting a variety of flavor volatiles into a modern tomato variety has resulted in altered flavor volatile profiles and improved flavor as assessed by a consumer panel.
Speakers
DT

Denise Tieman

University of Florida
Co-authors
HK

Harry Klee

University of Florida
NA
MA

Modesta Abugu

North Carolina State University
NA
Friday September 27, 2024 2:45pm - 3:00pm HST
Coral 1

2:45pm HST

LOCSY - Response of Leafy Edibles Grown on an Extensive Greenroof Compared to Conventional Field Production
Friday September 27, 2024 2:45pm - 3:00pm HST
Urban green roof (GR) agriculture provides an alternative growing space to supply fresh produce and herbs to local markets or restaurants, which can also help to address food security concerns in cities, by providing nutritional produce in urban and often underserved locations. Although many vegetables can be grown on extensive GRs, few studies have evaluated the performance of edibles grown on green roof environments to those grown under typical field conditions. Unlike traditional agriculture, plants on extensive GRs are grown in a shallow engineered soil to reduce the weight load on the roof. Therefore, an experiment was conducted in 2023 on the Southern Illinois University – Carbondale Agriculture building extensive green roof and at the Horticulture Research Center. This experiment evaluated ‘Dazzling Blue’ and ‘Red Russian' Kale [Brassica oleracea (Acephala Group)], and ‘Green Wave’ Mustard (Brassica juncea) productivity in both an extensive green roof environment and open field conditions. Similar cultural practices were followed regarding plant spacing, fertilizer and water management in both systems. The experiment was setup as a CRD with two treatment locations evaluating three edible green varieties with four replications. Results indicated a significant yield cost for these leafy edibles when gown on the greenroof compared to the conventional field environment. Fresh weight of ‘Dazzling Blue’ and ‘Red Russian Kale were reduced by 85% and 80% when grown in the GR environment, respectively, while that for ‘Green Wave’ Mustard was decreased by 70%. Data for other growth variables, such as plant height and vigor, leaf count, and dry weight were also generally reduced in an extensive GR environment and will be presented and discussed further. Although our research indicates that extensive GRs do not provide similar yields for leafy green edibles as conventional field production, this alternative urban space used to grow fresh food for an urban community may more than make up for the loss in yield due to the various significant positive impacts that GRs can provide.
Speakers
KL

Kaitlyn Lamaster

Horticulture Instructor, Southern Illinois University
Co-authors
AW

Alan Walters

Southern Illinois University
HM

Hunter M Christenson

Southern Illinois University
NA
Friday September 27, 2024 2:45pm - 3:00pm HST
South Pacific 1

2:45pm HST

O/LT 3 - Endophytic N Fixing Bacteria Isolated From Warm-season Turfgrasses and Common Lawn Weeds
Friday September 27, 2024 2:45pm - 3:00pm HST
The turfgrass industry has attempted to adopt market available N fixing bacterial strains to supply exogenous N requirements. However, turfgrass inoculations with market available N fixing strains have led to inconclusive results. Research on naturally occurring N fixers has mainly focused on abundance and diversity on roots and below ground soil. These ecological niches are known to be impacted by regular management practices of turfgrass which also interfere with the colonization rates of microorganisms. Therefore, the use of endophytic N fixing bacteria which are naturally present in turfgrasses such as bermudagrass, creeping bentgrass, and tall fescue is an attractive alternative regarding a higher microbial stability and potential of colonization. In this study we evaluated the culturing potential of N fixing bacteria from three turfgrass and three common weed species, assayed their potential to grow under different ammonium chloride (NH4Cl ) concentrations, and compared the isolates with the dominant taxa from a previous study in the community composition of N fixing bacteria in ‘CitrablueTM’ St. Augustinegrass [Stenotaphrum secundatum (Waltz)]. The plant biomass was collected from ‘CitrablueTM’, ‘Celebration’ bermudagrass [Cynodon. dactylon (L.)], ‘Empire’ zoysiagrass [Zoysia japonica (Steud)], goosegrass [Eleusine indica (L.) Gaertn], crabgrass [Digitaria sanguinalis (L.) Scoop], and bull paspalum [Paspalum setaceum (Michaux)]. The biomass was washed with water and surface sterilized using consecutive immersions in ethanol 75%, bleach 50%, and three rinses with ultrapure water. After sterilization, N fixers were isolated using a N free enrichment technique with Carbon Combined Media (CCM) and streaking on CCM solid plates. Taxonomy of the isolates was assigned using 16S and nifH Illumina miseq sequencing, consequently, the isolates were grown in liquid CCM with NH4Cl concentrations ranging from 100 uM to 0.001 uM. The isolates, Sphingomonas trueperi, Kosakonia radicitans, Herbaspirillum rubrisulbicans, Agrobacterium salinotolerans, Stenotrophomonas maltophilia, Kosakonia oryzae, Enterobacter sp. were not able to grow below 1 uM of NH4Cl in liquid CCM, however, these strains were the best performing strains because were able to grow at lower NH4Cl concentrations. Lastly, the isolates were not genotype specific to either turfgrasses or weeds and were not correlated with the dominant taxa of N fixers on the ‘CitrablueTM’ study.
Speakers
AF

Andrea F Arevalo Alvarenga

Graduate Assistant, University of Florida
Co-authors
MS

Marco Schiavon

University of Florida
US

Ulrich Stingl

University of Florida
NA
Friday September 27, 2024 2:45pm - 3:00pm HST
South Pacific 2

2:45pm HST

PNM 3 - Foliar Boron Nutrition in Grafted Watermelon: Impact on Fruit Development, Yield, and Quality
Friday September 27, 2024 2:45pm - 3:00pm HST
Grafting is an effective management strategy in watermelon crop against soil borne pathogens. Carolina strongback (SB) rootstock used for grafting, is resistant to both fusarium wilt and root knot nematodes which are devastating soil borne pests of watermelon. However, recent trials have shown that SB grafted plant bear fruits 7-10 days later than regulate plants leading to farmers losing early market which is more profitable. Further, tissue boron content in SB grafted plants were reported to be lower than regular watermelon nursery plants. Boron is the key micro-nutrient involves in cell wall and cell membrane, pollination, pollen germination, cell division, translocation of carbohydrates and fruit development. We hypothesize that foliar application of boron will cure the boron deficiency in grafted plants and leads to early fruit set similar to regular watermelon nursery. To test this hypothesis, a field experiment was conducted at Edisto Research and Education Centre, SC with the objective to evaluate the impact of foliar boron applications on pollen viability, pollination, fruit set, and periodic fruit yield as compared to regular watermelon nursery. The experiment was comprised of four treatments including a regular watermelon nursery control, in randomized complete block design. The soils had medium to low boron content of 0.1 pounds/acre. The soils were medium in potassium (133 pounds/acre), zinc (5.2 pounds/acre) and manganese (13 pounds/acre). Within first 25 days of transplanting, we did not observe any difference in the watermelon aboveground growth and biomass accumulation, in different treatments. Further, we will evaluate the impact of foliar boron application on pollen viability, pollination, watermelon fruit set, fruit yield and quality in SB grafted nursery.
Speakers
BJ

Bhupinder Jatana

Clemson University
Co-authors
TS

Tom Sanders III

Clemson University
NA
Friday September 27, 2024 2:45pm - 3:00pm HST
Lehua Suite

2:45pm HST

POM 4 - Effects of plum tree architecture on canopy light environments and fruit quality
Friday September 27, 2024 2:45pm - 3:00pm HST
In the orchard production system, upright or pillar trees with vertical branch orientations have narrow architecture profiles and therefore can be suited to high-density planting to increase productivity. In plum (Prunus domestica), there are natural variations of tree forms that range from upright to more horizontal growth habit. Recently, researchers at the USDA-ARS Appalachian Fruit Research Station demonstrated that silencing TILLER ANGLE CONTROL 1 (TAC1) via RNA interference (RNAi) in ‘President’ plum led to pillar tree forms with upright lateral shoot growth, whereas silencing LAZY1 in ‘Stanley’ plum resulted in outward shoot orientations and weeping tree shape. The objective of this study was to assess the effects of tree architectures on canopy light availability and fruit quality using field-grown mature (7-year-old) TAC1 and LAZY1 silenced plum trees in comparison with their respective non-transgenic counterparts as controls. Our results indicated that slender canopy profiles due to silencing of TAC1 allowed significantly greater light availability without negative impacts on fruit size, soluble solids contents, or titratable acidity compared to non-transgenic plum with the same genetic background. Additionally, skin color of fruit was more uniform in TAC1-RNAi lines than in standard-shaped control trees, suggesting a positive correlation between canopy light distribution and fruit coloration in association with upright branch orientations. In contrast, light availability in LAZY1-RNAi tree was reduced significantly by over 50% compared to the control. Although there is no difference in fruit size, soluble solids content in fruit of the LAZY1-RNAi plum than that of the non-transgenic counterpart.
Speakers
LT

Lisa Tang

USDA-ARS Appalachian Fruit Research Station
Co-authors
CD

Chris Dardick

Innovative Fruit Production, Improvement and Protection, Appalachian Fruit Research Station, Agricultural Research Service, (USDA)
NA
MF

Macarena Farcuh

University of Maryland
Friday September 27, 2024 2:45pm - 3:00pm HST
South Pacific 3

2:50pm HST

TCHG - Mentor-Mentee Perspectives And Experiences In A Graduate Scientific Communications Course
Friday September 27, 2024 2:50pm - 3:00pm HST
TPSS 654 Communications in the Sciences is a required one-credit graduate course in the Tropical Plant
Speakers
KD

Kent D. Kobayashi

Associate Professor, TPSS Dept., Univ. of Hawaii at Manoa
Co-authors
GR

Guadalupe Rodriguez

Univ. of Hawaii at Manoa
NA
Friday September 27, 2024 2:50pm - 3:00pm HST
South Pacific 4

3:00pm HST

TCHG - Student Engagement and Learning: Evaluating the Effectiveness of Digital Discussion Tools
Friday September 27, 2024 3:00pm - 3:10pm HST
Peer-to-peer engagement is an impactful way to enrich student learning and the teaching experience, especially in an asynchronous course. Varied online discussion platforms are more readily available to increase engagement, participation, and student learning. However, more information is needed to evaluate whether these discussion platforms enhance engaged learning. This study compares the use of online discussion platforms Packback and Yellowdig, used in sequential years for HS 205 (Sec. 601): Home Food Production - quantifying students' recorded level of participation, engagement with their classmates, and effort put into student posts. In the spring of 2022, Packback was evaluated as an effective class discussion tool for HS 205 (Sec. 601): Home Food Production. Students used Packback as the course discussion forum tool. Each week, they were given instructor-led lead discussion prompts during scheduled weeks and asked to respond to two of their peers. Packback tracked student participation each week and gave students a “curiosity” score. This curiosity score algorithm assessed the effort put into each student’s post. The Packback discussion group had lower full student participation, peer-to-peer engagement, and curiosity/effort scores. In the first week, most students fully participated. But as weeks progressed, the effort put into discussion posting and engagement significantly declined – as low as 65% participation. Beyond answering the discussion prompt, students did not develop their line of inquiry, and engagement was modest – most weeks, students did not fully participate, and the average curiosity score was 66% (the highest participation was 81 and the lowest 40). In the spring of 2023, Yellowdig was used as a digital tool to help create more vibrant, connected learning communities and give students the agency to discuss course topics that are important to them. Using Yellowdig, evidence showed that students became more active participants in the learning process, often exceeding the minimal participation requirement, and played a critical role in constructing knowledge. Crafted course topics provided course relevance and helped students talk about subjects related to the course, but no longer relied on instructor prompts for their discussions each week. With Yellowdig, students in this course performed above average in the number of student connections, the number of discussion posts, the number of reactions and responses given to discussion posts, the total word count average, and the number of multimedia shared (i.e.pictures, videos, weblinks). Furthermore, several students echoed their value of Yellowdig in their end -of-year evaluations.
Speakers
avatar for Remi Ham

Remi Ham

Assistant Teaching Professor, North Carolina State University
Remi HamAsst Teaching Professor and Distance Education CoordinatorKilgore Hall NA919-515-5373raham@ncsu.eduRemi’s body of work ranges from city planning, university planning, and project management. Her recent work has focused on designing edible teaching gardens and developing an environmental curriculum for K-12 schools. Additionally, Remi has focused on reducing food insecurity through com... Read More →
Friday September 27, 2024 3:00pm - 3:10pm HST
South Pacific 4

3:00pm HST

CE 9 - Explore a Cost-friendly Way for Plant Nitrogen Stress Identification
Friday September 27, 2024 3:00pm - 3:15pm HST
Plant stress can cause economic loss for plant production and is hard and expensive to identify at times. Thus, a greenhouse experiment was conducted to find an easy and cost-friendly way to identify plant stress, set up thresholds and values for the initiation of plant nitrogen stresses. Four different crops (basil, pepper, marigold, and sage) were included and treated with five different nitrogen levels (0%, 25%, 50%, 75%, and 100%). Plant height, width and leave greenless (indicated by SPAD) were measured weekly. Pictures were taken weekly. Software Image J was used to process pictures and R was used for data analysis. We found that plants with higher nitrogen treatments (75%-100%) all grow better and have higher SPAD than other treatments, except for bail. Also, RGB value could indicate plant nitrogen status with high accuracy. Plants become nitrogen stressed when SPAD falls to 25. Red and green values in RGB have negative correlations directly with SPAD and indirectly with nitrogen stress status. When the R and G values are higher than 150 and 185, respectively, we can safely predict that the plant is nitrogen stressed. In conclusion, using RBG value can be a cost-friendly way for plant stress identification.
Speakers
PY

Ping Yu

University of Georgia
Co-authors
KQ

Kuan Qin

University of Georgia
Friday September 27, 2024 3:00pm - 3:15pm HST
Nautilus 1

3:00pm HST

FRBR 2 - Linking Cultivar Evaluations – Phenology, Metabolomics, Consumer Preferences, and Postharvest Handling of ‘Glenn’ Mango
Friday September 27, 2024 3:00pm - 3:15pm HST
Mangos are the fifth most consumed fruit in the world (World Atlas). The top five mango producers include India, China, Indonesia, Pakistan, and Mexico (World population). Puerto Rico is the largest U.S. mango producer (2,666 acres), followed by Florida (2,455 acres), Hawaii (497 acres), California (328 acres), and Texas (10 acres). There are thousands of mango cultivars worldwide and the development and selection of new cultivars is ongoing. However, relatively few cultivars have a combination of information on their phenology, metabolomic profiles, consumer preferences, and postharvest handling. Describing and linking these cultivar evaluations and attributes may improve marker-assisted breeding efforts to develop and select for superior mango flavor, aroma, and nutritional value, improve understanding of hedonic consumer preferences, and result in improved postharvest handling and processing of mango. For example, ‘Glenn’ mango is a moderately vigorous tree with an upright open canopy that is generally dormant from November through December-January that flowers during February-March in response to warming ambient temperatures and is harvested during June-July. Historical descriptions are that it is a fruit of excellent eating quality with a rich, aromatic (pineapple notes) flavor, low fiber, and sweet pulp. This is borne out by the nonvolatile physiochemical characteristics of the cultivar including an average TSS of 15.93, TA of 0.65, and TSS/TA ratio of 24.41, with high concentrations of fructose, glucose, isocitric acid, and ketoglutaric acid. Defining nonvolatile flavor constituents from partial least-squares discriminant analysis for ‘Glenn’ mango were fructose, glucose, sucrose, isocitric acid, ketoglutaric acid, malonic acid, and gallic acid whereas defining volatile aroma constituents included ten esters (e.g., ethyl acetate, ethyl butanoate, and ethyl octanoate) that have floral, citrus, sweet, fruity, pineapple, and coconut notes. Results from a consumer sensory (taste, flavor, texture, fibrousness, juiciness, etc.) acceptance study indicated consumers like ‘Glenn’ mango because of its sweetness, tropical flavor, low fiber content, and juiciness, bearing out historical descriptions of this fruit. More detailed metabolic biosynthesis mapping linked flavor precursors and intermediates to the constituents responsible for flavor and aroma of ‘Glenn’. Postharvest evaluations reported ‘Glenn’ was moderately susceptible to hot water treatment injury, significant anthracnose incidence, only slight chilling injury (if stored below the 13°C recommended temperature) and could be stored for at least 3 weeks.
Speakers
JH

Jonathan H Crane

University of Florida, TREC
Co-authors
CS

Charles Sims

University of Florida IFAS
NA
JK

Jeffrey K Brecht

University of Florida, IFAS
NA
YW

Yu Wang

University of Florida
Friday September 27, 2024 3:00pm - 3:15pm HST
Kahili

3:00pm HST

GG 5 - Genome-Wide Association Study Identifies Key SNPs Associated with Mineral Element Accumulation in Spinach (Spinacia oler
Friday September 27, 2024 3:00pm - 3:15pm HST
Understanding the genetic basis of mineral element contents in crops is crucial for improving their nutritional value. This study conducted a comprehensive Genome-Wide Association Study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with the accumulation of 14 essential mineral elements in spinach (Spinacia oleracea). Utilizing a diverse collection of 281 spinach accessions, we assessed the content of Boron (B), Calcium (Ca), Cobalt (Co), Copper (Cu), Iron (Fe), Potassium (K), Magnesium (Mg), Manganese (Mn), Molybdenum (Mo), Sodium (Na), Nickel (Ni), Phosphorus (P), Sulfur (S), and Zinc (Zn), expressed in micrograms or milligrams per gram of dry weight (µg/gDW or mg/gDW). Genotyping revealed 83,952 SNPs across the spinach genome, analyzed using GAPIT3 and TASSEL5 software platforms. Statistical models employed included General Linear Model (GLM), Mixed Linear Model (MLM), FarmCPU, and BLINK within GAPIT, alongside SMR and GLM in TASSEL. Our analysis uncovered 33 significant SNP-trait associations distributed among the minerals: one for B, Cu, P, and K; two for Ca, Ni, Fe, Zn, and S; three for Mo and Mg; four for Na and Co; five for Mn. These findings highlight the genetic diversity influencing mineral nutrient accumulation in spinach and offer valuable markers for breeding nutritionally enhanced spinach varieties.
Speakers
HX

haizheng xiong

University of Arkansas
Co-authors
avatar for Ainong Shi

Ainong Shi

Associate Professor, University of Arkasnas
Dr. Ainong Shi is a faculty member in the Department of Horticulture at the University of Arkansas. His research laboratory specializes in plant breeding and genetics, particularly focusing on vegetable crops such as arugula, cowpea, and spinach for cultivar and germplasm development... Read More →
HA

Hanan Alkabkabi

University of Arkansas
NA
IA

Ibtisam Alatawi

University of Arkansas
NA
KC

Kenani Chiwina

University of Arkansas
NA
Friday September 27, 2024 3:00pm - 3:15pm HST
Coral 1

3:00pm HST

LOCSY - Diverse Internships as an Opportunity to Engage Underrepresented Students Into Local Food Systems
Friday September 27, 2024 3:00pm - 3:15pm HST
Climate change, food insecurity, and environmental degradation are complex food system challenges that require innovative and interdisciplinary approaches to agricultural research and education. In addition to attracting and training more students to food system and agricultural careers, there is a critical need for targeted recruitment of under-represented groups. To meet the demand for skilled professionals and increase minority participation in the agricultural workforce, the Center for Environmental Farming Systems (CEFS) has been developing new internship programs that reflect the changing career paths, as well as diverse interests and needs of students. Over the past five years, CEFS has strategically redesigned and expanded our student internship opportunities. In 2023, CEFS hosted 5 different student internship programs with 37 students with opportunities that ranged from summer research intensives to remote year round opportunities where students worked with food based community nonprofits. Key aspects of all of our internship programs include paid work opportunities, experiential learning, mentorship, professional development opportunities and cohort based learning. All student participants participated in pre- and post tests designed to collect program evaluation, participant knowledge and skills gains, as well as participants' intended career choices. Over the past three years, more than 50% of all program participants were from underrepresented minority groups. Additionally, 54% of interns reported that program participation led to a career pursuit in agriculture or food systems. Short term follow up studies to date show the majority of participants are either working in agriculture or food systems or completing additional studies in a related field. By engaging these diverse undergraduate students in hands-on, agriculture and food system research and extension opportunities while providing structured professional development training, we have increased underrepresented student interest and capacity to pursue careers in agriculture and food systems.
Speakers
AC

Angel Cruz

North Carolina State University
Research Scholar at NC State University
Co-authors
SK

Sara Kidd

North Carolina State University
NA
Friday September 27, 2024 3:00pm - 3:15pm HST
South Pacific 1

3:00pm HST

O/LT 3 - Mowing Mediated Root Radial Transport of Lead in Cynodon dactylon (L.) Persoon
Friday September 27, 2024 3:00pm - 3:15pm HST
Moderate mowing has been demonstrated as an effective strategy for aiding soil Pb remediation using bermudagrass. However, the precise mechanisms by which mowing facilitates the absorption and transport of Pb in bermudagrass remain unclear. Radial transport of Pb in roots governs the amount of Pb loaded into xylem vessels, where Pb ions are translocated upward into shoots. This study aims to investigate the radial transport pathways and their characteristics of Pb in bermudagrass under Pb and mowing treatments to elucidate the underlying mechanisms. The results indicate a shift in Pb distribution within the bermudagrass roots under mowing treatments. Specifically, there was a decrease in Pb distribution in the root apoplast accompanied by an increase in the root symplast. Under mowing conditions, the synthesis of abscisic acid and jasmonic acid in roots was significantly induced, leading to a delayed development and deposition of the endodermal barriers (Casparian strips and suberin lamellae). This reduction in the contribution rate of the apoplastic bypass inhibited Pb from entering the stele via the apoplastic pathway. Conversely, mowing pretreatment inhibited Pb absorption in roots but promoted Pb absorption in shoots under treatments with metabolic and ion channel inhibitors. Additionally, Pb2 net influx in the root apex was remarkably enhanced, and the expression of Pb absorption- and transport-related genes (CdNramp5 and CdHMA2) were upregulated following mowing application, suggesting that mowing promoted Pb transport through the symplastic pathway. Overall, this study provides the first evidence that mowing mediates the radial transport of Pb in bermudagrass. Mowing enhances the absorption and root-to-shoot transport of Pb primarily by increasing the efficiency of the symplasmic pathway.
Speakers
XC

Xinyi Cai

University of Georgia
Co-authors
DZ

Donglin Zhang

University of Georgia
XL

Xi Li

Sichuan Agricultural University
NA
Friday September 27, 2024 3:00pm - 3:15pm HST
South Pacific 2

3:00pm HST

PNM 3 - Optimization of Tissue Culture Medium for Enhanced Proliferation of Little-Leaf Mockorange (Philadelphus microphyllus A.
Friday September 27, 2024 3:00pm - 3:15pm HST
Native plants play a crucial role in landscape ecosystems due to their adaptability, yet propagating certain species through traditional methods can pose challenges. Tissue culture emerges as a promising alternative for efficient propagation, demanding an optimized culture medium for desirable proliferation. Efficient proliferation of newly introduced plant species in tissue culture often necessitates meticulous experimentation with varying salt compositions to optimize mineral concentrations and growth regulator levels within the culture medium. This study aimed to employ Response Surface Methods (RSM) to assess the effects of different mineral combinations, including nitrogen (N), calcium (Ca), potassium (K), and phosphorus (P), along with a cytokinin (zeatin), on the shoot proliferation and growth of little-leaf mockorange in tissue culture. Forty-six treatment combinations were designed, with zeatin concentrations of 0.82, 1.095, or 1.37 µM, and varying levels of N (22.5, 30, or 37.5 mM), Ca (1.125, 1.5, or 1.88 mM), P (0.31, 0.625, or 0.94 mM), and K (5, 10, or 15 mM). These treatments were evaluated for their impact on axillary shoot formation, shoot length, and shoot dry weight. Response surface analyses revealed optimal concentrations of N (32.5 to 35 mM), Ca (1.5 mM), and P (0.625 mM), while the influence of potassium on responses was found to be nonsignificant in the regression models, hence, K concentrations were limited to linear trends in the analysis. Notably, medium supplemented with 1.1 µM zeatin demonstrated a significant positive impact on shoot proliferation. The RSM model demonstrated the feasibility of determining optimal concentrations of zeatin, N, Ca, and P in a single experiment, facilitating the in vitro growth of little-leaf mockorange shoots. This study underscores the efficacy of RSM in tissue culture experiments, offering a time- and cost-effective alternative to conducting multiple separate experiments and providing valuable insights into medium optimization. Such findings contribute to the advancement of tissue culture techniques, particularly in propagating native plant species critical for landscape sustainability.
Speakers
avatar for Razieh Khajehyar

Razieh Khajehyar

Scientist, University of Idaho, Germains Seed Technology, Inc.
Co-authors
RT

Robert Tripepi

University of Idaho
NA
SL

Stephen Love

University of Idaho
NA
WJ

William J. Price

University of Idaho
NA
Friday September 27, 2024 3:00pm - 3:15pm HST
Lehua Suite

3:00pm HST

POM 4 - Does the Utah Model Still Work in Utah? Evaluation of Existing Phenological Models for Tart Cherry in a Changing Climate
Friday September 27, 2024 3:00pm - 3:15pm HST
Phenological models use local temperature data to predict spring flower bud development and guide management decisions in temperate fruit crops. In high elevation continental regions such as the U.S. Intermountain West, changing climate brings more extreme temperature variability resulting in increased risk of spring freeze damage. We evaluated bloom dates of tart cherry (Prunus cerasus L. ‘Montmorency’) in a high elevation continental climate (1327 to 1484 m elevation, Utah) to test the validity of 50-year-old phenological models under current climatic conditions. Mature commercial tart cherry blocks were selected in proximity to existing weather stations (climate.usu.edu, FGNet). Bud stages were observed weekly in April and May of 2019 through 2023 with 3 to 8 locations monitored per year. Observed stages were compared to Utah Standard and Modified prediction models. Prediction error varied with year and stage of development, where 2023 bloom was on average 3 days earlier than predicted, compared to 2020 when bloom was 6 days later than predicted. Modern weather stations provide more detailed climatic data (hourly temperature, light, humidity, wind speed), and the opportunity to refine and improve existing models. Improved model reliability would provide better decision support for increasingly expensive freeze protection measures.
Speakers
JM

Josette Moon

Utah State University
Co-authors
BB

Brent Black

Utah State University
NA
MS

Melanie Stock

Utah State University
NA
Friday September 27, 2024 3:00pm - 3:15pm HST
South Pacific 3

3:10pm HST

TCHG - Training the Next Generation of Leaders to Facilitate Successful and Resilient Urban Food Systems
Friday September 27, 2024 3:10pm - 3:20pm HST
Kansas State University formally began working in Urban Food Systems (UFS) with the launch of an UFS specialization in the Horticulture graduate program in 2011. In 2013 it expanded to the KSU-Olathe campus in order to be closer partners and other stakeholders in the Kansas City area. This program provides interdisciplinary training that focuses on sustainable urban food production, local food accessibility, food systems project management, grant writing, public and farmer education, and safe food production in an urban environment. Students gain a foundation in horticultural science while studying how the urban food system impacts social and economic development. There are a number of working urban agriculture professionals that do not have formal education or accreditation in these important topics. Therefore, the MS specialization has a thesis and a professional track (report) option that is intended for working professionals. Based on stakeholder feedback and marketing study performed by KSU, it became clear that there is a strong need for this type of education nationally and for working professionals. An online graduate certificate in urban food systems in January 2022 to address this need. The certificate consist of 6 required credits and 6 elective credits from approved courses in plant and agricultural science, leadership and management, sociology, economics and health. Fall 2023, the professional track MS is available 100% online. Graduates of the program are well prepared to work as director/program managers in not-for-profit organizations, city governments, and extension programs in urban districts, facilitating community gardens, urban farming, farmers’ markets, and farm-to-school programs. Details about the curriculum of the MS specialization and the interdisciplinary graduate certificate will be presented. As urban food systems continue to expand across the US and internationally, it will take a diverse group of professionals to address the complex issues that are relevant to this growing discipline.
Speakers
EP

Eleni Pliakoni

Kansas State University
Co-authors
CR

Cary Rivard

Kansas State University
JC

Jeremy Cowan

Kansas State University
NA
TJ

Tricia Jenkins

Kansas State University
Friday September 27, 2024 3:10pm - 3:20pm HST
South Pacific 4

3:15pm HST

CE 9 - Optimization of Irrigation Based on Substrate Type for Tomato Production in the Dutch Bucket Hydroponic System
Friday September 27, 2024 3:15pm - 3:30pm HST
Dutch bucket hydroponic systems are used for high-wire crop production such as tomatoes, cucumbers, or peppers, and are typically filled with perlite as a substrate. Through past research, our group identified pine bark and wood fiber as sustainable alternative substrates for high-wire tomato production. Typically, greenhouse tomato growers utilize leachate-based or timed irrigation; however, the use of a water content sensor could precisely identify the irrigation set-point for different substrates, potentially saving water and fertilizers. This study aimed to optimize the irrigation rate for greenhouse tomato ('Favorita F1') production in the Dutch bucket hydroponic system using a soil water content sensor. Three types of substrates (perlite, pine bark, and wood fiber-coir mix (60:40)) and four different gravimetric water contents (100%, 120%, 140%, and 160%) were considered. The experiment was conducted with three replications in a completely randomized design, with the irrigation treatments under the perlite substrate serving as the control. Physical parameters, such as the number of leaves and plant height, were significantly higher in the wood fiber-coir mix and pine bark at 160% irrigation, and lowest under perlite at 100% water content. However, there was no significant difference among the treatments for the number of flower (fruit) clusters. The plant leaf area measurements indicated better vegetative growth with wood fiber-coir mix at 160% water content, whereas pine bark at 160% water content resulted in a higher yield and better fruit quality. In contrast, phytochemicals such as Brix, vitamin C, titratable acidity, lycopene, beta-carotene, and phenolic compounds were significantly higher in the organic substrates (pine bark and wood fiber) with low water content (100% to 120%) and lower in perlite with high water content (140% to 160%). The highest and lowest concentrations of phytochemicals varied between 13% to 67%. There was no significant difference among the treatments (substrates and water contents) in terms of tissue mineral analysis. In general, plants grown in wood fiber-coir mix treatments required 28% and 51% less irrigation compared to those in pine bark and perlite treatments, respectively. Plants grown in organic substrates require less water, and the yield quantity and quality are either similar to or higher than those in perlite. Out of the organic substrates, wood fiber-coir mix can be used in Dutch bucket systems to conserve water and nutrients, enhancing yield quantity and quality, and thereby achieving environmental sustainability.
Speakers
MC

Milon Chowdhury

The Ohio State University
Co-authors
JM

Joanna Moine

The Ohio State University
NA
US

Uttara Samarakoon

The Ohio State University
Friday September 27, 2024 3:15pm - 3:30pm HST
Nautilus 1

3:15pm HST

FRBR 2 - Evaluation of Small Fruit Germplasm at the North Willamette Research and Extension Center
Friday September 27, 2024 3:15pm - 3:30pm HST
Since the 1920’s, Oregon State University (OSU) and the United States Department of Agriculture (USDA) Horticultural Crops Production and Genetic Improvement Research Unit have cooperated in the public breeding and development of small fruit cultivars to support Pacific Northwest (PNW) production. Together, the PNW states of Oregon and Washington have significant berry production with 152,407 metric tons of blueberry (Vaccinium spp.), 24,494 metric tons of red and black raspberry (Rubus idaeus; R. occidentalis), 9,525 metric tons of blackberry (Rubus spp.), and 6,804 metric tons of strawberry (Fragaria x ananassa) in 2022. Processed berries are the primary regional market, with fresh market production a lesser but still important driver for small farms. To continue to improve regional production of high-quality fruit, cultivar development has been a top tier research priority for PNW berry commodity commissions over the past decade. The cooperative breeding program has a continual germplasm improvement cycle that includes plant material in all stages of development, from seedlings, observational and replicated field trials, grower trials, and cultivar releases. After seedling evaluation, promising advanced selections of strawberry, blueberry, blackberry, red raspberry, and black raspberry crops are assessed at the OSU North Willamette Research and Extension Center in Aurora, Oregon. The USDA and OSU cooperative breeding program, in collaboration with Washington State University, has a uniquely strong focus on developing machine harvestable small fruit cultivars. Over 20 cultivars have been released with a value to PNW industries of over $450 million in the last ten years. ‘Tillamook’ strawberry, and ‘Black Diamond’ and ‘Columbia Star’ blackberry lead the acreage in Oregon and were developed by the program. More than 50 berry cultivars have been released since 1942 exclusively by the USDA with another 16 jointly-released with other agricultural universities and international corporations. This presentation will outline the cooperative breeding framework, discuss breeding priorities, and highlight new and upcoming cultivar releases.
Speakers
PJ

Patrick Jones

Oregon State University
Co-authors
AD

Amanda Davis

Oregon State University
NA
JL

Jungmin Lee

USDA-ARS
NA
MP

Mary Peterson

USDA-ARS
NA
SL

Scott Lukas

Oregon State University
NA
TM

Ted Mackey

USDA-ARS
NA
ZW

Zachary Wiegand

Oregon State University
NA
Friday September 27, 2024 3:15pm - 3:30pm HST
Kahili

3:15pm HST

GG 5 - Comparative Analyses of Tissue-Specific Transcriptome Responses to Salt Stress in Lettuce Roots and Leaves
Friday September 27, 2024 3:15pm - 3:30pm HST
Lettuce is one of the most important leafy vegetable crops world-wide. Salt stress adversely affects lettuce production, leading to considerable yield losses. Understanding the molecular mechanisms underlying the salt stress response is essential for breeding and development of lettuce cultivars with improved salt tolerance. Thus, the objective of this research was to identify differentially expressed genes (DEGs) in lettuce root and leaf tissues under salt stress and non-salt stress conditions. We have compared two salt-stress tolerant and two salt-sensitive accessions from crisphead and leaf horticultural types. Differential gene expression was compared between salt-tolerant and salt-sensitive accessions from the same horticultural type to minimize the effect of horticultural types on the comparison. In the root samples of the salt-tolerant accessions, we identified 3,789 and 4,022 DEGs, while for the salt-sensitive accessions 9,030 and 9,945 DEGs were identified, for the crisphead and leaf types, respectively. In leaf tissues, we observed 5,683 and 9,445 DEGs in the salt-tolerant accessions and 5,836 and 10,172 DEGs in the sensitive accessions, respectively, for the crisphead and leaf types. Thus, the number of DEGs was higher in sensitive accessions of both root and leaf tissues, with a notably greater disparity in root tissues. Functional annotations of the DEGs indicated stress response as a common biological process in both root and leaf tissues. Protein phosphatase inhibitor and peroxidase were the most significantly enriched molecular function terms in roots, while chaperone and glycosyltranferase molecular function terms were most significantly enriched in leaves. Gene Ontology (GO) enrichment analysis determined that genes related to the organic substance biosynthetic process were most significantly enriched in roots, while genes related to photosynthesis, response to light stimulus, chlorophyll binding and regulation of the jasmonic acid-mediated signaling pathway were significantly enriched in leaves. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that plant hormone signal transduction, biosynthesis of secondary metabolites, and the MAPK signaling pathway were significantly enriched terms in both root and leaf tissues, while cysteine and methionine metabolism terms were most significantly enriched in roots and photosynthesis was most significantly enriched in leaves. Identification of the salt-stress responsive genes and the results on their expression patterns in salt-tolerant vs salt-sensitive cultivars obtained in the present study open the door for further functional analysis of these genes and their utilization in improving salt-stress tolerance in lettuce.
Speakers
MD

Modan Das

USDA-ARS
Co-authors
BM

Beiquan Mou

USDA-ARS
NA
IS

Ivan Simko

USDA-ARS
NA
Friday September 27, 2024 3:15pm - 3:30pm HST
Coral 1

3:15pm HST

LOCSY - Food Policy and Food Security
Friday September 27, 2024 3:15pm - 3:30pm HST
Food policy and food security are two areas crucial to the success and health of many around the world. They take the commitment, hard work, and perseverance of many stakeholders from producer to consumer to legislation. Furthermore, as the population of the world continues to expand, an increase in production does not necessarily correlate to increased accessibility to healthy quality produce, building or support of local food systems or communities. Although methods can be implemented on a small community level, there are many opportunities to create more hospitable environments for horticultural production in Oklahoma. This leads to the current project to evaluate the state of the state’s food policy and plans for food security in hopes of providing strategies to best advise legislation and to ease barriers local producers experience through their advocacy. Additionally, as extenuating factors play into food security, it is important to factor in other areas of concern in policy and available resources, such as economics and regional factors. This presentation follows the research and analysis of the master’s project. Food policy is essential in supporting local producers, whether through resources, addressing barriers, or creating a pro-agricultural environment. Food policy also lead into many additional factors such as accessibility, especially for underserved populations, and the creation of healthier, more aware, and sustainable communities.
Speakers
SD

Sophia Darrow

Oklahoma State University
Co-authors
JM

Justin Moss

Oklahoma State University
NA
Friday September 27, 2024 3:15pm - 3:30pm HST
South Pacific 1

3:15pm HST

O/LT 3 - Cool-season Turfgrass Biomass and Ecosystem CO2 Flux as Affected by Fertilization and Irrigation
Friday September 27, 2024 3:15pm - 3:30pm HST
Concerns about the environmental impacts of lawns, including a high climate footprint, can pose challenges to the acceptance of natural turfgrasses. There are limited assessments of how to enhance turfgrass carbon sequestration and reduce management inputs in turfgrass systems in the northwest U.S. The goal of this study was to evaluate how fertilization and irrigation management can affect the ability of mixed cool-season turfgrass stands to sequester carbon. Annual rates of 0 and 196 kg N ha−1 were evaluated in the fertilization trial, while a non-irrigated control and 0.6 cm of precipitation applied four times per week in the summer months were compared in the irrigation trial. A portable clear chamber with a CO2 gas analyzer was used to measure CO2 fluxes. Grass clippings were collected from each plot to measure dry weight and subsequently returned to their respective plots. Clipping data were summarized as annual clipping production rates. Turfgrass standing biomass was sampled in 2021 and 2022 after summer stress and separated into aboveground (verdure) and belowground (thatch and roots) biomass. Our results indicated that the annual fertilization rate of 196 N ha−1 significantly increased photosynthesis in cool-season turfgrass in the winter and early spring compared to the unfertilized control. Fertilization also increased the net ecosystem exchange (NEE) rate in the winter, but the increases in NEE were less frequently observed than in the photosynthetic rate. Moreover, higher respiration rates were occasionally observed with the fertilization treatment. In contrast, fertilization had little to no effect on NEE, photosynthesis, and ecosystem respiration rates during the summer. Fertilization resulted in higher annual clipping yield, whereas there were no statistical differences between fertilization and no fertilization treatments in above- or below-ground biomass. In the irrigation study, the growth of turfgrass without irrigation ceased during summer as evidenced by reduced photosynthetic rates that were close to 0. Summer irrigation also stimulated ecosystem respiration which offset the benefits of enhanced photosynthetic rates, suggesting that further research is needed to identify the optimum irrigation practice for enhancing net CO2 assimilation. Irrigation produced greater annual clipping production in 2021 but had no effect in 2022. Irrigation was also shown to significantly increase aboveground biomass, but belowground biomass was not affected by irrigation. These results provided a better understanding of cool-season turfgrass growth in the Pacific Northwest U.S. so that cultural practices can be refined for more climate-friendly turfgrass management.
Speakers
RW

Ruying Wang

Oregon State University
Co-authors
AK

Alec Kowalewski

Oregon State University
NA
CM

Clint Mattox

USDA-ARS
NA
EB

Emily Braithwaite

Oregon State University
NA
ZH

Zachary Hamilton

Oregon State University
NA
Friday September 27, 2024 3:15pm - 3:30pm HST
South Pacific 2

3:15pm HST

PNM 3 - Nano NPK and Salicylic Acid Chemigation in Processing Tomato Production: Impact on Efficiency and Sustainability
Friday September 27, 2024 3:15pm - 3:30pm HST
Chemical fertilizers are key to enhancing tomato productivity, yet their excessive or imbalanced use can lead to higher costs, energy inefficiency, and negative environmental impacts. Recent advancements in nano fertilization seek to optimize nutrient use, minimize losses, and improve farm economics and environmental sustainability. Additionally, salicylic acid (SA) as a chemical inducer has shown potential to boost crop yields by enhancing stress tolerance in plants. Our research evaluated the effects of various rates of nano NPK fertilization combined with SA chemigation on the efficiency and sustainability of processing tomatoes (Solanum Lycopersicum L., cv. BHN 685) production in a drip-irrigated plasticulture system. Conducted over the 2022 and 2023 growing seasons, this two-factorial experiment tested nano NPK rates (0, 40, 80, 120 kg/ha) and SA levels (0 vs. 0.3%), using conventional NPK fertilizers as the control. The results showed that tomato yields were significantly influenced by SA chemigation, nano NPK fertilization, and the growing year, without interactive effects between and among these factors. SA chemigation with 120 kg NPK/ha increased yields by 9% compared to the control. Yields were similar between the 120 kg/ha SA chemigation and 120 kg/ha nano NPK treatments but were significantly higher (by 21%) under the 120 kg nano NPK with SA chemigation, suggesting effective synergy between SA and nano fertilization. SA chemigation and NPK fertilization reduced cull fruit yields, with nano NPK showing the most substantial reduction. Production costs were slightly higher for the combination of SA chemigation and nano NPK ($7,114/ha), but profitability was significantly increased, peaking at $2,487/ha in this treatment. Energy use efficiency also increased from 42.3% in the control (120 kg NPK/ha) to 51.1% with the combined treatment (120 kg nano NPK/ha with SA chemigation), and specific energy use per unit of tomato was decreased from 1.9 MJ/kg to 1.6 MJ/kg. Greenhouse gas emissions per ton of tomato were reduced from 46.3 kg CO2 equivalent/ha in the control to 42.7 kg/ha with combined nano NPK and SA chemigation. In conclusion, nano NPK fertilization coupled with SA chemigation proves to be an effective strategy for enhancing the efficiency and sustainability of processing tomato production, improving yield, profitability, and environmental outcomes.
Speakers
TH

Thomas Harker

Research Assosiate, The Ohio State University
Thomas Harker currently holds a research associate position specializing in horticultural and specialty crops at the Ohio State University South Centers. With an extensive career spanning over 25 years, he has been deeply immersed in the exploration and enhancement of various crops... Read More →
Co-authors
AR

Arifur Rahman

The Ohio State University South Centers
NA
BB

Brad Bergefurd

Brandt Discovery
NA
EB

Ed Brown

The Ohio State University Extension Athens County
NA
RI

Rafiq Islam

The Ohio State University South Centers
NA
WL

Wayne Lewis

The Ohio State University South Centers
NA
ZG

Zhenhao Guan

The Ohio State University South Centers
NA
Friday September 27, 2024 3:15pm - 3:30pm HST
Lehua Suite

3:15pm HST

POM 4 - A Mobile Cartographer System to Measure Tree Growth Within Tart Cherry Orchards
Friday September 27, 2024 3:15pm - 3:30pm HST
Temperate orchard sites have highly variable soils that contribute to uneven tree growth, providing a unique setting for precision management efforts. Precision management seeks to map spatial variability and implement variable rate management to optimize inputs. The objective of this study was to develop a platform for simultaneous measurement of tree growth and size to facilitate the enhancement of precision management practices in tart cherry (Prunus cerasus) orchards. Measurements included: canopy light interception; canopy height, volume, and width; and trunk cross sectional area (TCSA). Light interception (ceptometry) was by 15 30-cm line quantum sensors recording PAR at 0.6-second intervals, positioned on a UTV-mounted boom that passed under the canopy. Light interception was calculated based on data from a reference PAR sensor placed outside the orchard. Canopy height, width and volume of individual trees were measured using a side-scan LiDAR system mounted to the same UTV that generated point-cloud maps of each orchard row. These canopy measurements were then compared to point-cloud maps generated from aerial visual imaging (UAV). TCSA was estimated using a stereovision depth camera that captured paired visual spectrum (RGB) and point-cloud images, that were then aligned and segmented for individual tree trunks. Using pixel depth data, trunk widths for individual trees were estimated. The platform and associated sensors were used to map four commercial tart cherry orchard blocks (8-10 ha) located near Santaquin, Utah, USA, during the 2023 (ceptometry and UAV, only) and 2024 seasons at 2-week intervals. During the 2023 season, 8 ceptometry maps were generated with corresponding UAV-based maps. Side scan lidar data for 1 map of canopy height, width, and volume were collected in each of the 4 orchards, along with data for 1 TCSA map. Preliminary analysis shows strong spatial agreement among mapping techniques, indicating that the technologies are well suited to precision orchard management. Data for 2024 will also be presented, with multi-season tree growth analysis.
Speakers
BB

Brent Black

Utah State University
NA
Co-authors
BS

Bailey Shaffer

Utah State University
NA
GC

Grant Cardon

Utah State University
NA
KW

Kurt Wedegaertnerr

Utah State University
Friday September 27, 2024 3:15pm - 3:30pm HST
South Pacific 3

3:20pm HST

TCHG - Students’ Knowledge of Landscape Sustainability, Soil Quality and Climate Change Across Experiential Learning Courses i
Friday September 27, 2024 3:20pm - 3:30pm HST
Higher education institutions play a crucial role in shaping the future by preparing students to address global sustainability challenges. As we incorporate sustainability principles into teaching and research, faculty members are increasingly adopting an interdisciplinary approach. In particular, colleges of agriculture recognize the urgency of addressing soil degradation, climate change, and land management practices—the very threats that jeopardize global sustainability. However, teaching sustainability is no simple task. Students often grapple with the complexities of land degradation, soil health issues, and the impact of global warming on agriculture. Balancing the need to cover sustainability comprehensively while empowering students to find solutions can be challenging. In response to this challenge, a collaborative effort emerged across five different agriculture college courses. These courses leveraged experiential-learning projects focused on soil quality indicators and climate change mitigation as tools for teaching sustainability concepts. Despite varying levels (ranging from 300 to 400), these courses intentionally shared common components and included research projects, shared readings and reflections, student presentations and a symposium for research competition. The study analyzed over 40 research projects on soil quality and 85 student reflections. The results revealed that students not only acquired a deeper understanding of soil quality variations but also recognized how changes in soil health serve as indicators of land degradation or improvement. Moreover, they appreciated the vital role soil health plays in mitigating climate change. This collaborative approach demonstrates the effectiveness of experiential learning in teaching sustainability. By integrating real-world challenges and fostering interdisciplinary connections, higher education institutions can empower students to become informed stewards of our planet’s future.
Speakers
II

I I N HANDAYANI

Murray State University
Co-authors
AS

Alyx Shultz

Murray State University
NA
BP

Brian Parr

Murray State University
NA
Friday September 27, 2024 3:20pm - 3:30pm HST
South Pacific 4

3:30pm HST

TCHG - Evaluating In-person and Online Video Teaching Methods to Introduce Landscape Equipment Operation and Safety
Friday September 27, 2024 3:30pm - 3:40pm HST
Universities are adapting their teaching methods to progress with changes in technology. With these shifts in teaching, researchers are interested in which methods are best for certain applications. In the agriculture/horticulture realm, there are many studies describing the effects of online vs traditional in-class learning. Most of these studies focus on plant identification and generic species knowledge of plants. This study's purpose is to determine the efficacy of online vs traditional hands-on learning with eight types of landscaping equipment. The study was completed in the fall semester of 2023 at Kansas State University during the Sustainable Landscape Maintenance class. The class was randomly divided into two groups and exposed to one of two teaching methods (hands-on and online videos). Eight commonly used landscape equipment were taught to the students: power hedge trimmer, rotary push mower, de-thatcher, over seeder, ride-on zero-turn mower, sod cutter, string trimmer, and core aerifier). Both the videos and the in-person teaching covered proper operation and safety for each piece of equipment. One group was given in-person, hands- on learning the first week, while the other group watched online videos over the same four pieces of equipment. The following week, the groups switched teaching method delivery and learned the other four pieces of equipment. The students were given a pre- and post-test to assess their comprehension of the equipment. They also participated in a survey after the experiment to show prior experience on the equipment and comfortability after the labs. Results showed that students learn landscape equipment better in person through hands- on learning, rather than relying only on videos. The survey also showed students prefer hands-on demonstrations to become more comfortable operating these pieces of equipment.
Speakers
LD

Levi Dreiling

Kansas State University
Friday September 27, 2024 3:30pm - 3:40pm HST
South Pacific 4

3:30pm HST

CE 9 - The Secondary Metabolite Production and Growth Responses of Cannabis to Thigmomorphogenesis in a Controlled Environment
Friday September 27, 2024 3:30pm - 3:45pm HST
As legalization continues to change the cannabis industry, we see an influx of creative innovation, funding, and research as more entities enter the field. The two innovative growing management investigated in this study were Mechanical Vibration Training (MVT) and High Stress Training (HST). MVT was carried out using a grid exposing the plants to 200 Hz vibration, and HST is a practice that involves damaging the vascular bundles, pith, and cortex of the main stem while leaving the epidermis intact. MVT is a newer technique still in development, as Thigmo-priming has been shown to change plant morphology and chemistry and even increase the speed and magnitude of future stress responses. Many industry leaders claim that the advantages of using HST include higher canopy, increased biomass and cannabinoid concentrations, and more effective IPM strategies. However, studies validating these claims are still being determined. This study aims to compare each growing management under the overall category of Thigmomorphogenesis or mechanostimulation against control (no artificial mechanical stimulation) and tease out any synergism between the treatments. We hypothesize that applying mechanostimulation to cannabis plants will enhance their growth and increase secondary metabolite production. The environment-controlled growth units housed the treatments consisted of 1-Control, 2-MVT, 3-HST, and 4-MVT HST. Each growth unit contained five-gallon fabric pots with a single Suver Haze plant. An amended coco coir substrate was used with a water-soluble nutrient solution, and optimal growing conditions, including lighting, were maintained equally in all environment-controlled growth units. Weekly plant parameters included stem diameter, plant height, NDVI, chlorophyll concentration, and photosynthetic efficiency. After-harvest parameters included above/below ground biomass, yield mass, bucked biomass, trichome density, and cannabinoid levels. Morphological and numerical differences between treatments indicated the potential for a shorter, more efficient growth cycle with higher cannabinoid levels. Further testing is currently underway.
Speakers
JF

Jose Franco Da Cunha Leme Filho

Southern Illinois University
Co-authors
AA

Aldwin Anterola

Southern Illinois University
NA
DO

Dila Ozev

Southern Illinois University
NA
GS

Gorman Saunders

Southern Illinois University
NA
JW

Jennifer Weber

Southern Illinois University
NA
KG

Karla Gage

Southern Illinois University
NA
SS

Shiksha Sharma

Southern Illinois University
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
Nautilus 1

3:30pm HST

FRBR 2 - Developing a Genomic Framework for Selection of Fruit Attributes in Cold Climate Interspecific Grapes (Vitis Spp.)
Friday September 27, 2024 3:30pm - 3:45pm HST
Hybrid grapevines (Vitis spp.) grown in cold climate regions have fruit chemistries which do not adhere to the standard ranges of European wine grapes (Vitis vinifera L.) that many consumers may be accustomed to. The variation in fruit chemistry observed in hybrid grapevines is driven by a combination of genetics of parent material, which often builds on wild Vitis species, and the environmental conditions of production, which are often characterized by low heat accumulation and limited duration of growing season. Characterizing the genetic basis of fruit attributes enables breeders to understand and improve the relative quality of interspecific grapevines for future cultivar development. To address this knowledge gap for breeders, an incomplete diallel population of interspecific hybrid grapevines was assessed over a period of three years. Fruit chemistry (total soluble solids, pH, total acidity, glucose, fructose, malic acid, tartaric acid, citric acid, and yeast assimilable nitrogen content) and berry mass were examined at three distinct time points within each growing season to yield a total of nine phenotyping events. Best linear unbiased predictors (BLUPs) calculated from multi-year phenotype data were then interrogated via GWAS analysis to identify significant marker-trait associations. Chromosomes 16, 6, and 17 were noted to have the highest number of associations observed. To further understand the specificity of observed loci, gene annotation was conducted to reveal several important genes potentially related to the phenotypes. Due to the quantitative nature of fruit attributes, genomic selection strategies were explored to assess their accuracy for improving population performance in a systematic manner. Cumulatively, this analysis provides important information regarding the role of genetics in major fruit traits of interspecific cold hardy grapevines, regions of interest for fine mapping, and strategies for genomic selection. These analyses contribute towards the goals of improving breeding efficiency and selection accuracy to reduce generation timeline in grapevines.
Speakers
VR

Venkateswara Rao Kadium

Montana State University
Co-authors
AS

Andrej Svyantek

Montana State University
NA
CA

Collin Auwarter

North Dakota State University
NA
JS

John Stenger

North Dakota State University
NA
RP

Ramesh Pilli

North Dakota State University
NA
XL

Xuehui Li

North Dakota State University
NA
ZW

Zhuoyu Wang

Montana State University
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
Kahili

3:30pm HST

GG 5 - QTL Mapping Of Horticulturally Important Plant Architectural Traits In Cucumber (Cucumis sativus L.)
Friday September 27, 2024 3:30pm - 3:45pm HST
Cucumber (Cucumis sativus L.) is an economically important vegetable crop cultivated worldwide. Plant architectural traits, such as lateral branch number (LBN), vine length (VL), number of nodes (NN) and internode length (IL), may directly influence production practices, plant performances, fruit yield and quality. Despite their importance, investigation on the genetic basis of these traits in cucumber is limited. In this study, we conducted QTL mapping for VL, NN, IL and LBN using bi-parental F2, F2-derived F3 and recombinant inbred line (RIL) populations. There are significant positive correlations between LBN, VL and NN. Estimated board-sense heritability using entry-mean basis of the RIL population was high, ranging from 0.66 to 0.84. Two linkage maps were developed through genotyping-by-sequencing of 140 F2 individuals and Diversity Arrays Technology (DArTag) SNP genotyping of 135 RIL, containing 1912 and 334 SNP loci in seven linkage groups and spanning 1077 and 948 cM, respectively. QTL mapping analysis detected a total of 79 QTLs associated with the four traits in six environments or populations. Based on their physical locations, 66 QTLs were distributed in ten QTL clusters harboring four major-effect and six minor-effect QTLs. Each of the major- and minor-effect QTLs was supported by consistent and reproducible detection from at least three environments. Notably, major-effect QTLs for VL, NN and LBN were co-localized in two genomic regions on Chr1 (3.73 Mbp) and Chr6 (3.78 Mbp), and the major-effect QTL for IL was mapped in a 3.98-Mbp region on Chr5. These findings provide a framework for dissecting the genetic architecture of these complex traits, and valuable genetic information for cucumber breeders to employ molecular-assisted breeding approaches and develop improved varieties with enhanced productivity.
Speakers
TN

Thi Nguyen

Research Assistant, University of Wisconsin- Madison
Co-authors
YY

Yassine Yahia

University of Wisconsin-Madison
NA
YW

Yiqun Weng

University of Wisconsin-Madison
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
Coral 1

3:30pm HST

LOCSY - An Urban Agriculture Green Roof Study: Cultivating Sustainable Local Food Sources
Friday September 27, 2024 3:30pm - 3:45pm HST
Numerous cities have extensive roof space, a significant portion of which is comprised of unused flat rooftops. Green roofs are used to introduce green space to cities by growing plants on otherwise barren surfaces, especially in dense urban areas. Potential benefits of green roofs include social, economic, and environmental impacts. In addition, fruits and vegetables can be grown on roofs for consumption. Using a survey, practices such as design methods, community engagement, irrigation methods, plant selection, and growing substrate types were examined on 15 green roofs. The survey responses revealed several anticipated trends, including the provisioning of additional irrigation and a minimum of six hours of sunlight daily required on nearly all rooftops. There was also a large variety of plants that were reported to do well, suggesting that rooftop farms and gardens can successfully grow several different crops. One unexpected discovery was the common use of rooftop farms and gardens for restaurants and the unique culinary production associated. Overall, the studied roofs generally followed very similar designs, with a few distinct aspects that made them unique. In the future, more of these food-producing green roofs could further promote locally sourced healthy food within communities. The evidence obtained from this study defines the strategies and feasibility of urban agricultural practices on green roofs. These practices can increase locally sourced food production and provide a template for designing rooftop edible gardens for community-wide benefits.
Speakers Co-authors
MR

Mikayla Roth

NC State University , former graduate student
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
South Pacific 1

3:30pm HST

O/LT 3 - The 2023 Arkansas Diamond Plant Evaluation Trials
Friday September 27, 2024 3:30pm - 3:45pm HST
Arkansas’ research-backed plant assessment initiative known as "Arkansas Diamonds" aims to educate local gardeners on annual bedding plants that consistently thrive in Arkansas's climate. Moreover, it serves to bolster local growers and independent garden centers within the state. Facilitated by the Arkansas Green Industry Association (ARGIA) and the University of Arkansas System Division of Agriculture (UADA), this collaborative effort engages county agents across Arkansas in annual demonstration plots. In 2023, thirty county agents partook in the statewide evaluation of four annual plant species. Each agent received nine replicants of each species and conducted monthly measurements of height, width, flower quality, and overall health. These findings, integral to the selection process, contribute to designating certain plants as "Arkansas Diamonds," signifying their suitability for the state's gardens and green industry. After evaluations, the selected plants are grown by ARGIA members and marketed on a statewide basis to encourage home gardeners and the landscape industry to incorporate these plants into their home landscapes and support the local green industry and independent garden center within the state.
Speakers
AB

Anthony Bowden

University of Arkansas
Co-authors
RF

Randy Forst

University of Arkansas
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
South Pacific 2

3:30pm HST

PNM 3 - Nano NPK and Salicylic Acid Chemigation on Tomato Phytochemicals and Fruit Quality
Friday September 27, 2024 3:30pm - 3:45pm HST
Tomato stands out as a premier high-value specialty crop globally. However, the inefficiency of conventional fertilizers in nutrient utilization necessitates excessive fertilization to maintain tomato yields, which adversely impacts fruit quality. Nanotechnology, aimed at precise nutrient management to enhance efficiency and economic viability in farming, is gaining attention in agriculture. Similarly, salicylic acid (SA) has emerged as a potential chemical inducer to enhance plant metabolic activities, stress tolerance, and crop yield in the face of climate change. Our two-year field study aimed to assess the impact of varying rates of nano NPK fertilization and SA chemigation on the phytochemical properties, nutritional quality, and fruit attributes of processing tomatoes (Solanum Lycopersicum L., cv. BHN685), relative to conventional fertilization. Employing a two-factorial drip-irrigated plasticulture setup in a completely randomized design, we tested four levels of nano NPK (0, 40, 80, and 120 kg/ha) and two levels of SA (0 vs. 0.3%), each replicated four times. Results showed that tomato fruits subjected to SA chemigation with nano-NPK fertilization exhibited a significant increase in concentration of phytochemicals. Notably, vitamin-A, vitamin-C, lycopene, β-carotene, polyphenol, flavonoid, anthocyanin, and antioxidant capacity displayed substantial increases ranging from 2.5% to 51.2% compared to the control. Particularly noteworthy were the remarkable enhancements in flavonoid and anthocyanin concentrations, registering at 50% and 51.2%, respectively. Conversely, application of nano NPK alone led to discernible increases solely in flavonoid and anthocyanin concentrations, accompanied by decreases in other phytochemicals. Further analysis underscored the synergistic benefits of SA and nano-NPK, resulting in superior color, taste, and phytochemical richness of tomato fruits. K-means cluster analysis corroborated the efficacy of the SA with nano NPK (120 kg/ha) treatment in eliciting optimal fruit characteristics. Moreover, quality assessment revealed the superiority of the SA nano-NPK (120 kg/ha) treatment, with a quality index of 0.61 compared to the control's 0.47, indicative of its superior attributes. Additionally, the nutritional quality index demonstrated a gradual increase in nutrient enrichment across treatments, with the SA and nano NPK (120 kg/ha) combination yielding the highest score. In conclusion, our study highlights the pivotal role of SA in conjunction with nano NPK (120 kg/ha) in enhancing tomato phytochemical content and overall fruit quality. These findings bear significant implications for optimizing horticultural practices and promoting sustainable food production endeavors.
Speakers
TH

Thomas Harker

Research Assosiate, The Ohio State University
Thomas Harker currently holds a research associate position specializing in horticultural and specialty crops at the Ohio State University South Centers. With an extensive career spanning over 25 years, he has been deeply immersed in the exploration and enhancement of various crops... Read More →
Co-authors
AR

Arifur Rahman

The Ohio State University South Centers
NA
BB

Brad Bergefurd

Brandt Discovery
NA
EB

Ed Brown

The Ohio State University Extension Athens County
NA
RI

Rafiq Islam

The Ohio State University South Centers
NA
WL

Wayne Lewis

The Ohio State University South Centers
NA
ZG

Zhenhao Guan

The Ohio State University South Centers
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
Lehua Suite

3:30pm HST

POM 4 - Enhancing Uniformity in Tart Cherry Orchards Through Precision Management and Variable Rate Fertilization
Friday September 27, 2024 3:30pm - 3:45pm HST
Tart cherry (Prunus cerasus) orchard sites are often chosen for favorable microclimates, and consequently exhibit highly diverse soil conditions that result in non-uniform tree growth and yield potential. There is increasing interest in utilizing precision management techniques to map tree vigor and implement variable rate management to optimize inputs and enhance uniformity. The objective of this study was to assess the variability of soil and canopy characteristics and implement prescription fertilizer rates based on the mapped variability. The study was conducted on four mature (18-22 years) commercial tart cherry orchard blocks (8-10 ha) located near Santaquin, Utah, USA. Soil variability maps for each orchard were generated through soil sampling, guided by surveying apparent electrical conductivity (ECa) using an electromagnetic induction meter. Spatial variability in tree vigor was quantified using satellite imagery provided by Simplot Smart Farm® Permanent Crop Analysis. Prescription fertilizer rates, derived from the variability maps, were applied to each block in the spring/summer of 2023 and 2024, which included granular fertilizer applied as a single application or as split applications based on each prescription map. Tree response to the prescription treatments were monitored every two weeks using a novel platform capable of mapping plant growth parameters including canopy height, volume, width, and density; and trunk cross sectional area (TCSA). By monitoring growth parameters within this timeframe, we were able to comprehensively evaluate within-seasonal fluctuations in growth. Soil sampling revealed significant correlations between ECa and soil texture. Preliminary results indicate significant within-orchard variations in mid-season tree vigor, that are also correlated with long-term growth characteristics (canopy size and density). Both long-term and short-term growth measures are also closely correlated with soil ECa (i.e. texture). The effect of variable fertilizer application within this soil texture variability will be discussed, offering insight into the effectiveness of precision management techniques in mitigating variability within tart cherry orchards.
Speakers
KW

Kurt Wedegaertner

Utah State University
Co-authors
BS

Bailey Shaffer

Utah State University
NA
BB

Brent Black

Utah State University
NA
GC

Grant Cardon

Utah State University
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
South Pacific 3

3:40pm HST

TCHG - Evaluating Student Understanding of Plant Physiological Processes After Class Presentations
Friday September 27, 2024 3:40pm - 3:50pm HST
Concepts of plant water use, photosynthesis, and respiration have historically been challenging for undergraduates in introductory horticulture courses. To increase student understanding of these concepts, we conducted a study in a principles of horticultural science course with two lab sections and a total enrollment of 51 students. After traditional lectures of these plant physiological processes concluded, we used a flipped classroom approach with the learners as teachers to increase student learning. Each lab section was divided into six groups, with 12 groups in total. Groups were assigned one of the three topics and presented their topic to two other groups of students. Five knowledge-based questions on each physiological process, 15 questions total, were included on a pre-test prior to hearing lectures. The same 15 questions were given on a post-test following the lectures, but prior to the student presentations. Those 15 questions were also included on the unit exam following the presentations. No significant differences were found between pre-test and exam scores when evaluated for specific topics students presented. However, an 80% overall score increase from the pre-test to the unit exam was reported. This correlates with student responses to a post-survey in which 80% of the students indicated they understood the other physiological processes better after hearing the group presentations. Our results show that a flipped classroom approach of students teaching students can be effective at increasing student understanding of difficult horticultural concepts.
Speakers
LD

Levi Dreiling

Kansas State University
Co-authors
AS

Alex Stanton

Kansas State University
NA
JD

Jacob Domenghini

Kansas State University
Friday September 27, 2024 3:40pm - 3:50pm HST
South Pacific 4

3:45pm HST

CE 9 - Simulated Climate-change-related Environmental Stressors Can Alter the Yield and Metabolomics of Tomato
Friday September 27, 2024 3:45pm - 4:00pm HST
Climate change challenges all aspects of food production, including standard greenhouse products, such as tomatoes. The cause of climate change can be directly attributed to the rise in carbon dioxide (CO2) levels, leading to increased temperatures and drought severity. Tomatoes are the most produced fruit crop globally, and in addition to their economic benefits contain several vitamins and minerals essential for human health. The objective of this study was to assess the multi-variable effects of simulated climate change on tomato plants by investigating the combination of elevated CO2 (800 ppm vs 400 ppm), increased temperature (28℃ vs 21℃), and water deficit stress (20% decrease from control) across three development stages: juvenile, anthesis, and fully mature tomato. ‘Sweet ‘N’ Neat Scarlet’ tomatoes (Solanum lycopersicum) were grown in four plant growth chambers in a 2 x 2 x 2 factorial design with four replications. Quality parameters included photosynthetic efficiency, growth index, dry weight, flower number, fruit number, and fruit size. Inductively coupled plasma mass spectrometry (ICP-MS) and oxygen radical absorbance capacity (ORAC) analyses were measured at each of the three stages when applicable. Preliminary data suggests that higher temperatures and CO2 increase (p
Speakers
MV

Marlo Vandiver

West Virginia University
Co-authors
JT

Janet Tou

West Virginia University
NA
NW

Nicole Waterland

West Virginia University
NA
YM

Youyoun Moon

West Virginia University
NA
Friday September 27, 2024 3:45pm - 4:00pm HST
Nautilus 1

3:45pm HST

FRBR 2 - U.S. Peach Production and Breeding Overview
Friday September 27, 2024 3:45pm - 4:00pm HST
Peach is an introduced crop with a relatively short production and breeding history in the U.S. The peach industries have been facing declines and challenges in both production and breeding activities over the past decades. Understanding of the statuses and issues facilitates gaining insights and finding solutions. This presentation is to provide an overview of U.S. peach production and breeding, including trends, issues, and prospects. Both U.S. peach acreage and production are declining, but market values increasing. Public peach breeding programs were established at the early time and helped establish considerable production in many states. But most of them have been terminated, phased out, or de-emphasized, largely due to declining production and economic impact. Taken into consideration all factors, visionary peach horticulture research and breeding solutions for some cost-related and yield-limiting production issues are essential for profitable and sustainable peach production in the future.
Speakers
Friday September 27, 2024 3:45pm - 4:00pm HST
Kahili

3:45pm HST

GG 5 - Screening Sweetpotato Germplasm for Resistance to Meloidogyne incognita
Friday September 27, 2024 3:45pm - 4:00pm HST
Meloidogyne incognita is the most common root-knot nematode found in agricultural regions worldwide. It can cause severe damage to many crops including sweetpotato storage roots, causing them to be unmarketable and resulting in significant yield losses. Identifying resistant crop varieties is one of the most effective ways to manage M. incognita. To identify germplasm with resistance to M. incognita, 47 sweetpotato accessions obtained from the USDA germplasm repository were screened in replicated greenhouse assays. ‘Beauregard’ was used as a susceptible control and ‘Regal’ as a resistant control. Sweetpotato slips containing 3 nodes each were planted in an autoclaved 1:1 mixture of sand and potting mix in Deepot D25L containers and arranged in a randomized block design, with 2-3 replicates per an accession. Two weeks after planting, each plant was inoculated with 10,000 M. incognita eggs. Eight weeks after inoculation, plants were harvested and rated for fibrosity, galling, number of egg masses, and eggs per gram of root. Resistance was defined as accessions with mean galling ≤ 10% and mean eggs per gram of root ≤ 500. Based on these criteria, 12 accessions were identified as having resistance to M. incognita.
Speakers
PW

Phillip Wadl

USDA, ARS, U.S. Vegetable Laboratory
Co-authors
CW

Catherine Wram

USDA, ARS, Mycology and Nematology Genetic Diversity and Biology Laboratory
NA
HB

Hannah Baker

USDA, ARS, U.S. Vegetable Laboratory
NA
WR

William Rutter

USDA-ARS
NA
Friday September 27, 2024 3:45pm - 4:00pm HST
Coral 1

3:45pm HST

LOCSY - Sustainable Small Plot Farming and Entrepreneurship Training Program
Friday September 27, 2024 3:45pm - 4:00pm HST
In response to growing concerns of food insecurity within our communities in the big bend region of Florida, Tallahassee State College in partnership with the City of Tallahassee established a training program to empower emerging farmers. This innovative program equips participants with the necessary skills and knowledge to efficiently and sustainably cultivate fruits and vegetables using organic and permaculture practices. The primary aim is to enable individuals to utilize small plots of land effectively, thereby fostering self-sufficiency and contributing to the local food community. The program was conceived as a direct countermeasure to the challenges of food scarcity and the underutilization of available land for food production. By focusing on small-scale, sustainable farming, the initiative seeks to transform even limited spaces into productive market gardens. This approach not only addresses immediate food production needs but also promotes long-term environmental stewardship through sustainable agricultural practices. A distinctive feature of the program is its partnership with local farms, which provides a practical, hands-on learning environment for participants. These collaborations are vital for the integration of theoretical knowledge with real-world farming experiences, enhancing the learning process. Historically, the program supported learners through paid apprenticeships, allowing them to earn while they learn. Since its launch, various sponsors have funded the program, offering scholarships that eliminate cost barriers. Presently, it’s supported by a USDA AFRI Agricultural Workforce Training grant, which includes equipment stipends and industry-recognized certifications. These additions aim to further support and broaden the participants' success in the agricultural sector. The certifications serve as a formal acknowledgment of their technical proficiency and a steppingstone towards further career opportunities in agriculture. Through its comprehensive curriculum, this program not only teaches participants how to grow food but also instills entrepreneurial skills necessary for starting and managing a market garden. This dual focus ensures that graduates are well-prepared to either enter the agriculture industry or start their own farming ventures. Ultimately, this program strives to create a network of skilled, knowledgeable farmers who are capable of contributing to their communities by increasing local food production and enhancing food security. By doing so, it supports not only the participants and their families but also enriches the broader local food ecosystem. The ongoing success of the program underscores its significance as a vital educational resource in the fight against food insecurity through sustainable agriculture.
Speakers
AH

Alexis Howard

Tallahassee Community College
Alexis is an environmental professional with a focus on agriculture education and entrepreneurship training. After earning a bachelor’s degree in Environmental Science and Policy from the Florida State University (FSU), Alexis acquired a job as a Program Assistant at Tallahassee... Read More →
Friday September 27, 2024 3:45pm - 4:00pm HST
South Pacific 1

3:45pm HST

PNM 3 - Alternative Fertilizer Methods For Palm Trees
Friday September 27, 2024 3:45pm - 4:00pm HST
Lack of water holding and cation exchange capacity severely limit fertilizer application methods for new palm tree transplants in sandy soils in S. Florida. Typically, palm trees are fertilized using an 8-2-12 4 granular fertilizer but with little rooting to enhance fertilizer capture and no soil solution to improve nutrient uptake, establishment may be slow. Alternative fertilizers, including palm tree injection, were evaluated to determine the best method to improve palm tree establishment under these conditions. A research trial was conducted using Christmas Palms (Adonidia merrillii) that were established on sandy soils with less than 2% organic matter. After planting, palms were not fertilized for six months. Palm trees were treated with the following fertilizers: 1) 8-2-12 4 (PS), 2) 0-0-22 4(KM) 3) PHOSPHO-jet PALM-jet injection (PJ) 4) PHOSPHO-jet PALM-jet apical meristem drench (AM) and 6) “Gator Grip” (GG) fertilizer pouch directed at the apical meristem. Visual quality and drone imagery were used to assess palm health. Volumetric water content (VWC) was determined at three different depths and root growth was captured using a mini-rhizotron. Six months after the initial treatment application, treatment differences were not visually apparent and VWC was below 10% for the majority of measurements captured at all depths. Rooting data at this stage was minimal. Palm trees may grow very slowly and under these environmental conditions, it may take the palm over a year to replace an entire crown. Therefore, yearly updates will be presented for this three-year trial to best determine which treatment provides the best solution to establish transplanted palms in the landscape and maintain palm health.
Speakers
MM

mica mcmillan

University of Florida
Co-authors
KW

Karen Williams

University of Florida
NA
NF

Naomi Franklin

University of Florida
NA
Friday September 27, 2024 3:45pm - 4:00pm HST
Lehua Suite

3:45pm HST

POM 4 - Tree temperature prediction to improve chill accumulation estimation in cherry under climate change
Friday September 27, 2024 3:45pm - 4:00pm HST
Timing application of dormancy breaking products is essential for adequate bloom and yield in cherry. Available temperature-based chill accumulation models often fail to predict correct spray timing, particularly during years with unusual temperature patterns recently driven by climate change. One potential cause for the unreliability of the current models is their dependence on a single climatic variable, air temperature, to estimate the impact of weather on tree physiological processes. We hypothesized that using tree temperature, rather than air temperature, will increase the accuracy in predicting chill accumulation, especially in warm and sunny winters. Hence, our objective was to develop a framework to predict cherry tree temperature based on easily available environmental data. For three consecutive seasons and in three commercial cherry orchards across California, including the southernmost US cherry production region, we measured main climatic parameters at half hour intervals. At the same time, we monitored tree temperature with T-type thermocouples inserted below the bark of main branches. We developed predictions of tree temperature as a function of meteorological variables obtained from public weather stations using generalized additive models. Trees were, on average, 10 ºF warmer than the air during clear days, with differences being up to 20-25 ºF. Tree chill accumulation was about 8-12 chill portions lower than air chill accumulation. The difference was year- and site-specific, reflecting the importance of including diverse environmental parameters to estimate chill accumulation precisely. The ‘TreeChill model’ predicts tree temperature based only on environmental parameters easily achievable from public weather stations with a coefficient of determination of 0.956 resulting in only 0.4 chill portions difference between measured and predicted tree chill. This model will enable growers to implement tree temperature in their management decisions, including dormancy breaking agent applications, cultivar selection, pest control etc, increasing California cherry industry resilience to climate change. In the future, we plan to adapt the model to different crops and locations.
Speakers Co-authors
AS

Aileen Salas

UC Davis
NA
AP

Amrit Pokhrel

UC Davis
NA
DR

Daniel Ruiz

UC Davis
NA
EL

Emilio Laca

UC Davis
NA
ES

Emily Santos

University of California, Davis
NA
KA

Kari Arnold

UC ANR
NA
PG

Paula Guzman-Delgado

University of California Davis
Friday September 27, 2024 3:45pm - 4:00pm HST
South Pacific 3

3:50pm HST

TCHG - Development of an Agricultural Biotechnology Core Capstone Course
Friday September 27, 2024 3:50pm - 4:00pm HST
The undergraduate core curriculum is an opportunity introduce students from diverse majors to topics in agriculture. Agricultural Biotechnology is an interdisciplinary undergraduate course at Delaware Valley University which combines the disciplines of Plant and Animal Science. It has run every spring semester since 2020, with enrollment made up of students from different majors. The course was recently approved as a core capstone course, an upper-level course intended to assess the university’s core curriculum, and it and was run as a core capstone course for the first time in 2024. The objectives of this project were to: 1) create two final course projects including a poster and case study designed to assess the core curriculum outcomes and 2) to provide students with the opportunity to develop their skills in public education and outreach. A final poster project was incorporated into the course in which students were instructed to develop a new Biotech trait in any plant or animal species. The poster project needed to address core curriculum outcomes such as global contexts, using relevant information, quantitative methods, appropriate technology, and required professional communication. The second case study project was used to assess multicultural competency. The posters were on display at events for both the campus community and the outside public. Student feedback was collected via pre-and post-tests and surveys.
Speakers
AK

Adrienne Kleintop

Delaware Valley University
Co-authors
RS

Robin Shedlauskas

Delaware Valley University
NA
Friday September 27, 2024 3:50pm - 4:00pm HST
South Pacific 4

4:00pm HST

FRBR 2 - Introduction of modern tools to the University of Arkansas System Division of Agriculture Fruit Breeding Program
Friday September 27, 2024 4:00pm - 4:15pm HST
The University of Arkansas System Division of Agriculture (UADA) has a legacy breeding program that has spanned three fruit breeders and 60 years. The UADA Fruit Breeding Program is large, complex, and works on multiple crops. A recent program initiative has been the introduction of modern tools for breeding approaches and data collection and management. This talk will outline the process for developing a molecular breeding pipeline for blackberry (Rubus subgenus Rubus Watson) and muscadine grape (Muscadinia rotundifolia) and outline how these approaches benefit program progress. Additionally, advances in data collection techniques such as digital evaluations using an application and development of barcoding systems for streamlining processes and minimizing error will be described.
Speakers
CJ

Carmen Johns

Assistant Fruit Breeder, University of Arkansas
Co-authors
Friday September 27, 2024 4:00pm - 4:15pm HST
Kahili

4:00pm HST

GG 5 - Variation for Non-Acclimated and Acclimated Heat Tolerance Among Potato Germplasm: Indication of Separate Genetic Control
Friday September 27, 2024 4:00pm - 4:15pm HST
Several studies have documented variation in potato germplasm for heat tolerance of leaf tissue. Most researchers have relied on screening for heat stress by exposing excised leaf tissue (grown under non-stress condition) to a short-term (minutes-hours) of acute heat stress (37-55C). It is well known that plants vary in their ability to acclimate to heat stress know as priming. This priming can enable plant to survive subsequent temperatures that are lethal to plants grown under non-stress condition. Our recent studies show that potato plants under prolonged heat stress (35/25C, day/night, for 3-5 weeks) newly developed leaves (acclimated) can maintain health under heat stress by modifying anatomy and physiology. These results show that potato plants have the ability to acclimate to heat stress that results in increased heat tolerance. In the present study, we screened to potato germplasm for heat tolerance of leaf tissue before and after heat acclimation. Ion leakage after exposure of excised leaf tissue to 50C, was used as a screening assay and a reduction in this leakage was used to assess the heat acclimation ability. Wide variety of potato germplasm including commercial cultivars and accessions of various wild species were screened. Our result show significant genotypic variations in acclimated and non-acclimated heat tolerance. Furthermore, the heat acclimation ability appears to be independent of non- acclimated heat tolerance. For example, certain clones of the species Solanum commersonnii had similar non-acclimated heat tolerance but large variation in acclimated tolerance was found among various clones of this species. Similar results were obtained for different clones of Solanum microdontum and Solanum kurtzianum. As expected, the cultivars Zarewo, DTO and Papa Cacho were found to have higher non-acclimated heat tolerance than the others, but Papa Cacho had the highest heat acclimation ability. Our results suggest that non-acclimated heat tolerance and acclimated heat tolerance are under separate genetic control and that selection for both non-acclimated and acclimated heat tolerance may be useful for successful breeding for heat tolerance of potato leaf tissue.
Speakers
JP

Jiwan Palta

UW Madison
Co-authors
AD

Alfonso DelRio

University of Wisconsin Madison
NA
JB

John Bamberg

University of Wisconsin Madison
NA
JS

Justin Schabow

University of Florida
NA
Friday September 27, 2024 4:00pm - 4:15pm HST
Coral 1
 
Saturday, September 28
 

7:30am HST

TOUR 3 - Waikiki Historic Trees
Saturday September 28, 2024 7:30am - 12:00pm HST
TBA
Saturday, September 28, 2024: 7:30 AM - Noon
Steve Nimz, renowned Hawaii arborist, with give a presentation based on his extensive experience in tree assessment and transplanting technologies. The actual tour will then continue by connecting science and technology with an actual walk though Waikiki, featuring some of the historic trees that the arborist will cover in his presentation. This includes: Waikiki International Marketplace, Moana Hotel, Waikiki Banyan by Duke Kahanamoku's statue and hula stage, and Kapiolani park.

Member Price: $55

Non-Member Price: $65
Advance registration is required. https://ashs.org/store/viewproduct.aspx?id=23258349
Details:
Depart Hotel: 8:30 am
Stop #1: Waikiki International Marketplace
Stop #2 Kapiolani park
Arrive back at Hotel: Noon

Saturday September 28, 2024 7:30am - 12:00pm HST
TBA

7:45am HST

TOUR 5 - Tour of Botanical Gardens on Oahu
Saturday September 28, 2024 7:45am - 5:00pm HST
TBA
This tour is sold out.

This tour featuring three botanical gardens on Oahu, will offer a glimpse of tropical plant collections and conservation efforts over the years.

Details:
Depart Hotel: 7:45 am
Stop #1: Waimea Valley Botanical Garden 
Stop #2 : Foster Botanical Garden/Lunch
Stop #3: Lyon Arboretum
Arrive back at Hotel: 5:00 pm

ASHS Professional Interest Group/Committee Sponsor*
Ornamental Plant Breeding

Saturday September 28, 2024 7:45am - 5:00pm HST
TBA
 


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