ASHS 2024 Conference: Full Schedule

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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

Alicia Herzog

Iowa Master Gardener Program Coordinator, Iowa State University

Thursday September 26, 2024 11:30am - 11:40am HST
Kahili

Poster presentation (individual talk), Consumer Horticulture and Master Gardeners

SUBJECT Consumer Hort and Master Gardeners

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

South Pacific 4

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

Jannatul Afroze

New Mexico State University

Co-authors

Breana Smithers

University of North Texas

Israel Joukhadar

New Mexico State University

Miguel Acevedo

University of North Texas

Stephanie Walker

New Mexico state University

Thursday September 26, 2024 11:30am - 11:40am HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

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

Kahili

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

Scott Langlois

Miss State University

Co-authors

Shaun Broderick

Mississippi State University

Tricia Knight

Mississippi State University

Thursday September 26, 2024 11:40am - 11:50am HST
Kahili

Poster presentation (individual talk), Consumer Horticulture and Master Gardeners

SUBJECT Consumer Hort and Master Gardeners

11:40am HST

VCM 3 - Planning for Success: A Roadmap to Establishing a Certified Naturally Grown Production Plot

Thursday September 26, 2024 11:40am - 11:50am HST

South Pacific 4

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

Shelby Mendoza

Oklahoma State University

Thursday September 26, 2024 11:40am - 11:50am HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

11:45am HST

UG 2 - Perceptions of Gardens and Gardeners

Thursday September 26, 2024 11:45am - 11:55am HST

Coral 1

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

Belinda Brain

Iowa State University

Thursday September 26, 2024 11:45am - 11:55am HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

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

Kahili

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

Leonard Githinji

Virginia State University

Co-authors

Julia Kabbani

Virginia State University

Thursday September 26, 2024 11:50am - 12:00pm HST
Kahili

Poster presentation (individual talk), Consumer Horticulture and Master Gardeners

SUBJECT Consumer Hort and Master Gardeners

11:50am HST

VCM 3 - Fertility Management in Soilless Growth Media for Beet Crop Production.

Thursday September 26, 2024 11:50am - 12:00pm HST

South Pacific 4

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

Bryce Waugh

Grad Student, Oklahoma State University

Co-authors

Bruce Dunn

Oklahoma State University

Thursday September 26, 2024 11:50am - 12:00pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

11:55am HST

UG 2 - Horticultural Activities Impact the Perceived Stress Levels of Undergraduate Students

Thursday September 26, 2024 11:55am - 12:05pm HST

Coral 1

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

Baylie Michele Latter

Iowa State University

Thursday September 26, 2024 11:55am - 12:05pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

12:00pm HST

CHMG/HIH/PUBHORT - Needs Assessment Evaluation to Inform Statewide Horticulture Newsletter

Thursday September 26, 2024 12:00pm - 12:10pm HST

Kahili

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

Cynthia Domenghini

Kansas State University

Thursday September 26, 2024 12:00pm - 12:10pm HST
Kahili

Poster presentation (individual talk), Consumer Horticulture and Master Gardeners

SUBJECT Consumer Hort and Master Gardeners

12:00pm HST

VCM 3 - Adaptation of AgRobotics for Onion Production in High Organic Matter Soils

Thursday September 26, 2024 12:00pm - 12:10pm HST

South Pacific 4

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

Mary Ruth McDonald

Professor, University of Guelph

Research and extension interests include vegetable production and crop protection, with the emphasis on onions, carrots, celery and Brassica crops. Also conducting research on soil health of high organic matter soils and agricultural robots.

Co-authors

Chuck Baerisch

Haggerty AgRobotics

Geoffry Farintosh

University of Guelph

Ifesinachi Ezeh

University of Guelph

Kevin Vander Kooi

Univ. of Guelph

Kristen Obeid

Ontario Ministry of Agriculture, Food and Rural Affairs

Thursday September 26, 2024 12:00pm - 12:10pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

12:00pm HST

WCPM 2 - Evaluating Bacterial Diversity and Pest Control Efficacy of Steam Disinfestation Treatments in the Salinas Valley Lettuce Fields

Thursday September 26, 2024 12:00pm - 12:10pm HST

South Pacific 2

As the threat of climate change intensifies, the need for sustainable and environmentally friendly pest and pathogen control methods in agriculture becomes increasingly urgent. Steam disinfestation, a method once considered outdated and replaced by chemical pesticides, is experiencing a resurgence due to heightened environmental concerns. Despite its historical use, there has been little exploration of scaling up steam disinfestation for field applications in vegetable crops.
This project focuses on evaluating the effectiveness of band steaming as a disinfestation method in lettuce fields in the Salinas Valley. The study is divided into two parts: the first part assesses pest control, while the second part examines the impact of band steaming on the soil microbiome.
Our goal is to validate band steaming as a viable alternative to chemical pesticides through a thorough assessment in agricultural fields. The experiment was conducted during 2023 trials at Hartnell’s USDA research facility in Salinas, CA, using a custom-built steam applicator with a 1,000 kg/hour low-pressure steam generator. Pest control analysis focused on Pythium spp., a soil-borne disease, and weed emergence, with disease assessment carried out through pathogen assays in soil samples. Additionally, we examined the impact of band steaming on the soil microbiome using 16S sequencing, collecting soil samples before, one day after, and 30 days after steam treatment.
Preliminary results show effective weed control and reduced pathogen pressure following steam treatments. Soil microbial analysis indicates that steam treatment influences changes in the soil microbiome, with some recovery in alpha, beta, and functional diversity observed within 30 days. Through a comprehensive assessment of pest control and soil microbial changes, we aim to provide detailed insights into the effectiveness of steam disinfestation and its potential for sustainable agricultural practices.

Speakers

Erika Escalona

graduate student, UC Davis

Co-authors

Steve Fennimore

UC Davis

Thursday September 26, 2024 12:00pm - 12:10pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

12:05pm HST

UG 2 - Perceptions of Media Literacy in Undergraduate Students and Master Gardeners

Thursday September 26, 2024 12:05pm - 12:15pm HST

Coral 1

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

Caleb Spry

Iowa State University

Thursday September 26, 2024 12:05pm - 12:15pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

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

Kahili

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

Jeff Wilson

Mississippi State University Extension

Thursday September 26, 2024 12:10pm - 12:20pm HST
Kahili

Poster presentation (individual talk), Consumer Horticulture and Master Gardeners

SUBJECT Consumer Hort and Master Gardeners

12:10pm HST

VCM 3 - Dual-cropping Sweetpotato for Greens and Root Production

Thursday September 26, 2024 12:10pm - 12:20pm HST

South Pacific 4

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<0.0001) than USDA-04-136 and USDA-04-791 (spreading growth habit), which produced 118 and 139 g, respectively. Total greens production was significantly higher for the early and continuous harvest treatments (ca. 219 g/plant) than for the late and control treatments (ca. 173 g/plant) (p<0.01). Marketable root yield was similar for all the greens harvest treatments and was significantly lower for all harvest treatments compared to the control (p<0.0001). Compared to the control treatment, marketable root yield was lowest for early harvest and continuous harvest (ca. 34%), and highest for late harvest (51%). Across all greens harvest treatments, marketable root yield was lower compared to the control in the spreading breeding lines (33% and 40% for USDA-04-791 and USDA-04-136, respectively) than in the semi-erect breeding line (51% for USDA-04-284). While sweetpotato can be dual cropped for both greens and roots, the production of greens as an additional vegetable crop must offset financial losses of decreased root yield. Harvesting sweetpotato greens later in the season or only immediately before root harvest can reduce root yield losses while still producing a substantial crop of greens. Erect cultivars are best suited for greens production due to the lesser impact of greens harvest on root yield and higher production of greens.

Speakers

Laura Schulz

Graduate Research Assistant, Washington State University

I am a PhD student at Washington State University working with Carol Miles on introducing sweetpotato as a new crop in western Washington.

Co-authors

Carol Miles

Washington State University

Jacob Blauer

Washington State University

Laurel Moulton

Washington State University

Phil Wadl

United States Department of Agriculture, Agricultural Research Service

Thursday September 26, 2024 12:10pm - 12:20pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

12:10pm HST

WCPM 2 - Development of Minirhizotron for Nondestructive Rapid Detection of Parasitic Nematodes

Thursday September 26, 2024 12:10pm - 12:20pm HST

South Pacific 2

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

Tim Pannkuk

Sam Houston State University

Co-authors

Autumn Smith-Herron

Sam Houston State University

Faruk Yildiz

Sam Houston State University

Junken Ma

Sam Houston State University

Recayi Pecen

Sam Houston State University

Thursday September 26, 2024 12:10pm - 12:20pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

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

Nautilus

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

Gursewak Singh

Graduate Research Assistant, Clemson University

Co-authors

Brian Ward

Clemson University

Jai Rohila

USDA-ARS

Matthew Cutulle

Clemson

Michael Marshall

Clemson University

Raghupathy Karthikeyan

Clemson University

Sarah White

Clemson University

Thursday September 26, 2024 12:15pm - 12:25pm HST
Nautilus

Poster presentation (individual talk), Genetics and Germplasm 2

SUBJECT Genetics and Germplasm

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

South Pacific 3

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

Duarte-Sierra Arturo

Assistant Professor, Université Laval

My research interests focus on postharvest physiology of fruits and vegetables. My hobbies are mountain hiking and bird photography.

Co-authors

Charles Goulet

Université Laval

Ernesto Alonso Lagarda Clark

Université Laval

Thursday September 26, 2024 12:15pm - 12:25pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Charlie Rohwer

Scientist, University of Minnesota

Co-authors

Emily E Evans

University of Minnesota

Lee Klossner

University of Minnesota

Paulo Pagliari

University of Minnesota

Thursday September 26, 2024 12:15pm - 12:25pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

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

Coral 1

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

Colin Krisulevicz

West Virginia University

Co-authors

Joseph Lynch

West Virginia University

Sven J Verlinden

West Virginia University

Thursday September 26, 2024 12:15pm - 12:25pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

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

Kahili

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

Terra Freeman

Urban and Commercial Horticulture Extension Agent, University of Florida

Thursday September 26, 2024 12:20pm - 12:30pm HST
Kahili

Poster presentation (individual talk), Human Issues in Horticulture

SUBJECT Human Issues

12:20pm HST

VCM 3 - Effect Of Selenium Fertilization on Beta-carotene Accumulation in Hydroponically Grown Two cress Varieties

Thursday September 26, 2024 12:20pm - 12:30pm HST

South Pacific 4

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

Adekunle Adeyeye

Kentucky State University, Frankfort, KY

Co-authors

Alex Kofi

Kentucky State University

Graduate Research Assistant

THEONESTE NZARAMYIMANA

Kentucky State University

Thursday September 26, 2024 12:20pm - 12:30pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

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

South Pacific 2

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

Bin Wu

Postdoctoral Research Associate, Texas A&M University

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

Hongmin Qin

Texas A

Hui Duan

USDA

Margaret Pooler

Floral and Nursery Plants Research Unit, U.S. National Arboretum, U.S. Department of Agriculture-Agricultural Research Service

Thursday September 26, 2024 12:20pm - 12:30pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

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

Nautilus

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

Eun Jin Lee

Seoul National University

Co-authors

Jeongyun Kim

Dankook University

Kyeonglim Min

Seoul National University

Thursday September 26, 2024 12:25pm - 12:35pm HST
Nautilus

Poster presentation (individual talk), Genetics and Germplasm 2

SUBJECT Genetics and Germplasm

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

South Pacific 3

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

yongtae kim

Andong National University

Co-authors

ByungChnu In

Andong National University

Ji Yeong Ham

Andong National University

Suong Tuyet Yhi Ha

Andong National University

Thursday September 26, 2024 12:25pm - 12:35pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Sentaro Tomiyama

Graduated student, Meiji University

Co-authors

Masako Osawa

Hagihara farm

Shingo Fujita

Hagihara farm

Takashi Ikeda

Meiji University

Xiangyu Cui

Meiji University

Yusuke Matsumoto

Meiji University

Thursday September 26, 2024 12:25pm - 12:35pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

12:25pm HST

UG 2 - Optimal production densities and storage conditions for five microgreens

Thursday September 26, 2024 12:25pm - 12:35pm HST

Coral 1

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

Sam Petrovich

West Virginia University

Co-authors

Sven J Verlinden

West Virginia University

Thursday September 26, 2024 12:25pm - 12:35pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

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

Kahili

African Americans (AA) have a rich history intertwined with agriculture, yet modern agricultural opportunities often elude them. Despite the industry

Speakers

Theoneste Nzaramyimana

Assistant Professor for Urban Agriculture/Controlled Environment, 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

Poster presentation (individual talk), Human Issues in Horticulture

SUBJECT Human Issues

12:30pm HST

VCM 3 - Effect Of Levels Of Magnesium Fertilization On The Carotenoid Accumulation Among Three Kale Cultivars Grown Hydroponically.

Thursday September 26, 2024 12:30pm - 12:40pm HST

South Pacific 4

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

Alex Kofi

Graduate Research Assistance, Kentucky State University

Graduate Research AssistantResearch interest: Controlled Environment Agriculture especially in hydroponics

Co-authors

Adekunle Adeyeye

Kentucky State University, Frankfort, KY

THEONESTE NZARAMYIMANA

Kentucky State University

Thursday September 26, 2024 12:30pm - 12:40pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

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

South Pacific 2

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

Amy Fulcher

University of Tennessee

Co-authors

Karl McKim

The University of Tennessee

Laura Whaley

University of Tennessee

Lauren Fessler

University of Tennessee

Lily Slade

University of Tennessee

Thursday September 26, 2024 12:30pm - 12:40pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

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

Nautilus

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

Alexander Luckew

University of Georgia

Thursday September 26, 2024 12:35pm - 12:45pm HST
Nautilus

Poster presentation (individual talk), Genetics and Germplasm 2

SUBJECT Genetics and Germplasm

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

South Pacific 3

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

Gasselle Cordova

University of Florida

Co-authors

Steven Sargent

University of Florida

Professor and Extension Postharvest Specialist

Zhanao Deng

University of Florida

Thursday September 26, 2024 12:35pm - 12:45pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Xiangyu Cui

Meiji University

Co-authors

Masako Osawa

Hagihara Farm Co.Ltd.

Sentaro Tomiyama

Meiji University

Takashi Ikeda

Meiji University

Thursday September 26, 2024 12:35pm - 12:45pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

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

Coral 1

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

Madison Coyle

Plant science student worker, Texas A&M University- Commerce

I am a sophomore in college majoring in horticulture. This is my second year of research.

Co-authors

Derald Harp

Texas A

Lindsey Trinkle

Texas A

Thursday September 26, 2024 12:35pm - 12:45pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

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

Kahili

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

Terra Freeman

Urban and Commercial Horticulture Extension Agent, University of Florida

Thursday September 26, 2024 12:40pm - 12:50pm HST
Kahili

Poster presentation (individual talk), Public Horticulture

SUBJECT Public Horticulture

12:40pm HST

VCM 3 - Red And Blue LED Lighting Effects On Hydroponically Grown 'Koba' Green Onion

Thursday September 26, 2024 12:40pm - 12:50pm HST

South Pacific 4

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

Kent D. Kobayashi

Interim Dept. Chair, TPSS Dept., Univ. of Hawaii at Manoa

Co-authors

Brylin Nelson

Univ of Hawaii at Manoa

Thursday September 26, 2024 12:40pm - 12:50pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

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

South Pacific 2

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

Amy Fulcher

University of Tennessee

Co-authors

Benjamin Lockwood

University of Tennessee

Cody Fust

Auburn University

Heping Zhu

USDA-ARS

Karl McKim

The University of Tennessee

Laura Whaley

University of Tennessee

Lily Slade

University of Tennessee

Thursday September 26, 2024 12:40pm - 12:50pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

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

Nautilus

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

Angela Linares Ramirez

Professor, University of Puerto Rico

Co-authors

Geoffrey Meru

University of Florida

Jorge Ruiz Menjivar

University of Florida

Miguel Garcia Carrucini

University of Puerto Rico - SEA

Thursday September 26, 2024 12:45pm - 12:55pm HST
Nautilus

Poster presentation (individual talk), Genetics and Germplasm 2

SUBJECT Genetics and Germplasm

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

South Pacific 3

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

katie stenmark

OKLAHOMA STATE UNIVERSITY

Crop Science PhD Student Department of Horticulture and Landscape Architecture Oklahoma State University

Co-authors

Charles Fontanier

OKLAHOMA STATE UNIVERSITY

NIELS MANESS

OKLAHOMA STATE UNIVERSITY

Thursday September 26, 2024 12:45pm - 12:55pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Samuel Essah

Colorado State University

Thursday September 26, 2024 12:45pm - 12:55pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

12:45pm HST

UG 2 - Strawberry Response to Compost Versus Inorganic Nitrogen

Thursday September 26, 2024 12:45pm - 12:55pm HST

Coral 1

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

Elizabeth De La Torre

University of Illinois Urbana-Champaign

Kauai Paule

University of Hawaii at Manoa

Thursday September 26, 2024 12:45pm - 12:55pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

12:50pm HST

VCM 3- Plant Health Aerial Mapping Integration In Precision Agriculture Systems

Thursday September 26, 2024 12:50pm - 1:00pm HST

South Pacific 4

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

Wael Elwakil

Extension Agent II, University of Florida

Thursday September 26, 2024 12:50pm - 1:00pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

12:50pm HST

WCPM 2 - Rice Hull Use in Container Production; Economics and Efficacy

Thursday September 26, 2024 12:50pm - 1:00pm HST

South Pacific 2

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

Shawn Steed

University of Florida

Thursday September 26, 2024 12:50pm - 1:00pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

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

Nautilus

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

Brianna Heilsnis

Graduate Research Assistant, Oregon State University

Co-authors

Jacob Snelling

Oregon State University

Shawn Mehlenbacher

Oregon State University

Thursday September 26, 2024 12:55pm - 1:05pm HST
Nautilus

Poster presentation (individual talk), Genetics and Germplasm 2

SUBJECT Genetics and Germplasm

12:55pm HST

PH 2 - Transcriptome Analysis Revealed that Metabolites and Hormone Signaling Pathway Differently Respond to Non-chilling and C

Thursday September 26, 2024 12:55pm - 1:05pm HST

South Pacific 3

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

Yujin Sim

Seoul national university

Co-authors

Eun Jin Lee

Seoul National University

Kyeonglim Min

Seoul National University

Thursday September 26, 2024 12:55pm - 1:05pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Dave Goorahoo

Professor, California State University, Fresno

Co-authors

Aldo Garcia

California State University, Fresno

Florence Cassel

California State University, Fresno

John Bushoven

California State University, Fresno

Thursday September 26, 2024 12:55pm - 1:05pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

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

Coral 1

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

Alana Marie Barros

University of Hawai’i at Manoa

Co-authors

Eric Collier

University of Hawai’i at Manoa

Megdelena Perkins

University of Hawai’i at Manoa

Theodore Radovich

University of Hawai’i at Mānoa

Thursday September 26, 2024 12:55pm - 1:05pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

1:00pm HST

PLAST - Conserving Soil Moisture in High Tunnels to Maintain Soil Health

Thursday September 26, 2024 1:00pm - 1:10pm HST

Kahili

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

Claire Barnhart

Kansas State University

Co-authors

Cary Rivard

Kansas State University

Eleni Pliakoni

Kansas State University

Jeremy Cowan

Kansas State University

Peter Tomlinson

Kansas State University

Tricia Jenkins

Kansas State University

Thursday September 26, 2024 1:00pm - 1:10pm HST
Kahili

Poster presentation (individual talk), Plasticulture

SUBJECT Plasticulture

1:00pm HST

VCM 3 - Evaluating Productivity and Growth Characteristics of Vegetable Soybean Varieties under Subtropical Climate

Thursday September 26, 2024 1:00pm - 1:10pm HST

South Pacific 4

Authors: You's Kertye Myrtil, Vander Lacerda, and Xiaoying Li

Edamame, a vegetable soybean harvested at an immature stage with green pods, has gained popularity in the United States due to its high nutritional value and taste, resulting in rising demand. However, limited information is available on the performance of edamame varieties in South Florida. This study aimed to 1) evaluate the field performance of fourteen commercial edamame varieties in South Florida to determine their adaptability for local production, and 2) explore correlations between yield, pod size, and plant physiological traits to identify key indicators for both fresh yield and pod size. The study assessed various phenotypic and agronomic traits at harvest, including yield, plant height, canopy size, leaf area, chlorophyll content, 10-pod weight, pod size (length, width, and thickness), root nodule count, and biomass (fresh and dry). Principal component analysis (PCA) identified Kahala, Goo, KAS 355-11, UA-Kirksey, and Young Soybean as the best performers, while Envy Soybean, Butterbeans, and Fiskeby were the poorest. Yield varied significantly among varieties (p<0.01). Strong correlations (r>0.70; p<0.01) were found between yield and traits such as biomass (fresh and dry), leaf area, and plant height and canopy size. Positive correlations were also observed between yield and maturity days (r>0.61; p<0.05), suggesting that later-maturing varieties tend to have higher yield potential in South Florida. On the other hand, pod size (length, width, and thickness) showed a positive correlation with 10-pod weight and biomass (both fresh and dry) at an r value of approximately 0.6 (p<0.05), but not with maturity days, chlorophyll content, or other factors. This indicates that biomass contributes to both yield and pod size. Interestingly, no correlation was found between yield and pod size, likely because yield was more closely related to the number of pods per plant. These findings provide valuable insights for selecting suitable edamame varieties for South Florida production.

Speakers

Xiaoying Li

University of Florida, IFAS

Co-authors

Vander Lacerda

You's Kertye Myrtil

Thursday September 26, 2024 1:00pm - 1:10pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

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

South Pacific 2

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

Manjot Sidhu

Michigan State University

Co-authors

Debalina Saha

Michigan State University

Thursday September 26, 2024 1:00pm - 1:10pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

1:05pm HST

GG 2 - The wonderful world of worms: Microbiota of rabbit manure vermicompost at different maturities

Thursday September 26, 2024 1:05pm - 1:15pm HST

Nautilus

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

June Labbancz

Texas A

Co-authors

Amanda Birnbaum

Texas A&M

Amit Dhingra

Texas A

Thursday September 26, 2024 1:05pm - 1:15pm HST
Nautilus

Poster presentation (individual talk), Genetics and Germplasm 2

SUBJECT Genetics and Germplasm

1:05pm HST

PH 2 - Fresh Weight of Indoor-Grown Lettuce under Different Postharvest Storage Practices

Thursday September 26, 2024 1:05pm - 1:15pm HST

South Pacific 3

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

Caroline Blanchard

Research Associate III, Auburn University

Co-authors

Camila Rodrigues

Auburn University

Daniel Wells

Auburn University

Marlee Trandel Hayse

Auburn University

Tanzeel Rehman

Auburn University

Thursday September 26, 2024 1:05pm - 1:15pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

CYRUS JANUARIE

Graduate Research Assistant, UNIVERSITY OF FLORIDA

Soil nutrient managementStatistical data analysisField research

Co-authors

Davie Kadyampakeni

University of Florida

Thursday September 26, 2024 1:05pm - 1:15pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

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

Coral 1

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

Miranda Woodcock

University of Kentucky

Co-authors

Brent Arnoldussen

University of Kentucky

Thursday September 26, 2024 1:05pm - 1:15pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student 2

SUBJECT Undergraduate Student

1:10pm HST

PLAST - Introducing A New Biobased, Biodegradable Mulch: Lignocellulosic Film

Thursday September 26, 2024 1:10pm - 1:20pm HST

Kahili

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

Aidan Williams

Washington State University

Co-authors

Haishun Du

University of Wisconsin-Madison

Lisa DeVetter

Washington State University

Teng Li

University of Maryland

Xuejun Pan

University of Wisconsin-Madison

Yuan Yao

Yale University

Thursday September 26, 2024 1:10pm - 1:20pm HST
Kahili

Poster presentation (individual talk), Plasticulture

SUBJECT Plasticulture

1:10pm HST

VCM 3- Lettuce Cultivar Trials in a Deep Water Culture (DWC) Hydroponic System

Thursday September 26, 2024 1:10pm - 1:20pm HST

South Pacific 4

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.

Speakers

Alireza Rahemi

Morehead State University

Co-authors

Alyssa F. Covell

Amy S. Collick

Caleen L. Treadway

Hudson M. Cox

Larry N. Goble

Mary H. Jackson

Mollie K. Mayabb

Randy W. Wilburn

River E. Crepps

Rylie B. St. Clair

Thursday September 26, 2024 1:10pm - 1:20pm HST
South Pacific 4

Poster presentation (individual talk), Vegetable Crops Management 3

SUBJECT Vegetable Crops

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

South Pacific 2

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

Supti Saha Mou

Michigan State Univ.

Co-authors

Debalina Saha

Michigan State University

Thursday September 26, 2024 1:10pm - 1:20pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

1:15pm HST

PH 2 - Modified Hydrocooling and Optimized Postharvest Handling Practices Can Improve the Shelf Life of Water Spinach During Su

Thursday September 26, 2024 1:15pm - 1:25pm HST

South Pacific 3

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

Wei Shiang Liao

Taoyuan District Agricultural Research and Extension Station, Ministry of Agriculture

Co-authors

Ah Chiou Lee

Taoyuan District Agricultural Research and Extension Station, Ministry of Agriculture

Wing Fu Fung

Taoyuan District Agricultural Research and Extension Station, Ministry of Agriculture

Thursday September 26, 2024 1:15pm - 1:25pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Shelbie Bohensky

University of Georgia

Co-authors

Timothy Coolong

University of Georgia

Thursday September 26, 2024 1:15pm - 1:25pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management

SUBJECT Plant Nutrient Mgmt

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

Coral 1

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

Abby Porter

Utah State University

Co-authors

Xin Dai

Utah State University

Youping Sun

Utah State University

Thursday September 26, 2024 1:15pm - 1:25pm HST
Coral 1

Poster presentation (individual talk), Undergraduate Student

SUBJECT Undergraduate Student

1:20pm 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 1:20pm - 1:30pm HST

Kahili

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

Hadi Ghasemi

PhD Graduate Assistant, University of Florida

Co-authors

Lisa DeVetter

Washington State University

Nathan Boyd

University of Florida

Shinsuke Agehara

University of Florida

Thursday September 26, 2024 1:20pm - 1:30pm HST
Kahili

Poster presentation (individual talk), Plasticulture

SUBJECT Plasticulture

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

South Pacific 2

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

Merci Uwimbabazi

Graduate Research Assistant, Kentucky State University

BSc in Conservation Agriculture / Pursuing a Master’s in Environmental Studies. Highly interested in Controlled Environment Agriculture and Horticulture.

Thursday September 26, 2024 1:20pm - 1:30pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

1:25pm HST

PH 2 - Discovery of Biomarkers for Postharvest Pecan Color Stability Using Metabolomics and Machine Learning Algorithms

Thursday September 26, 2024 1:25pm - 1:35pm HST

South Pacific 3

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

Min Jeong Kang

Graduate Research Assistant, University of Georgia

Hello! I am a 5th year Ph.D. candidate in the Food Science and Technology Department at the University of Georgia.My research interests are Metabolomics, using Machine Learning Algorithms to discover the biomarkers. My recent work involves evaluating pecan quality, looking at biomarkers... Read More →

Co-authors

Joonhyuk Suh

University of Georgia

Lenny Wells

University of Georgia

Patrick Conner

University of Georgia

Ronald Pegg

University of Georgia

William Kerr

University of Georgia

Thursday September 26, 2024 1:25pm - 1:35pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

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

South Pacific 1

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

Most Tahera Naznin

Associate Professor of Urban & Indoor Agriculture, University of Nevada, Reno

Co-authors

Jessica Nolan

University of Nevada, Reno

Thursday September 26, 2024 1:25pm - 1:35pm HST
South Pacific 1

Poster presentation (individual talk), Plant Nutrient Management 1

SUBJECT Plant Nutrient Mgmt

1:30pm HST

PLAST - Plastic and Biodegradable Mulches in Agroecosystem: A Comparative Life Cycle Assessment Perspective to Environmental Impact and Economic Considerations

Thursday September 26, 2024 1:30pm - 1:40pm HST

Kahili

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

Oluwatunmise Israel Dada

Graduate Research Assistant, Washington State University

A Ph.D. Candidate passionate about the natural environment and sustainable solutions.

Co-authors

Liang Yu

Washington State University

Ting Chi

Washington State University

Thursday September 26, 2024 1:30pm - 1:40pm HST
Kahili

Poster presentation (individual talk), Plasticulture

SUBJECT Plasticulture

1:30pm HST

WCPM 2 - Impact of Partial Saltwater Agroecosystems on Weed Competition in Watermelon

Thursday September 26, 2024 1:30pm - 1:40pm HST

South Pacific 2

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

Joseph Bazzle

Clemson University

Co-authors

A Levi

Brian Ward

Clemson University

H Schopp

Matthew Cutulle

Clemson University

Sandra Branham

Clemson University

Thursday September 26, 2024 1:30pm - 1:40pm HST
South Pacific 2

Poster presentation (individual talk), Weed Control and Pest Management 2

SUBJECT Weed Control and Pest Mgmt

1:35pm HST

PH 2 - Evaluating the Effects of Controlled Atmosphere Storage on Two Georgia-grown Pecan Cultivars

Thursday September 26, 2024 1:35pm - 1:45pm HST

South Pacific 3

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

Ramsey Corn

University of Georgia

Co-authors

Angelos Deltsidis

University of Georgia

Camille Esmel McAvoy

University of Georgia

Orestis Giannopoulos

University of Georgia

Thursday September 26, 2024 1:35pm - 1:45pm HST
South Pacific 3

Poster presentation (individual talk), Postharvest 2

SUBJECT Postharvest

3:00pm HST

PROP - K-IBA Promotes Adventitious Rooting of Bog Birch Stem Cuttings

Thursday September 26, 2024 3:00pm - 3:10pm HST

Nautilus

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 #1 nursery containers, bog birch propagated from 5 to 6-inch cuttings grew into upright, well-branched plants that were several feet tall, exceeding the total height of many plants we found in the bog environment from which we collected cuttings. Although we found the small, pubescent leaves with rounded margins on wild plants to be a key aesthetic trait, the same genotypes cultivated in containers produced broader leaves with reduced pubescence. Similarly, although plants in the wild often form small clonal colonies, plants in containers for one season were upright shrubs with no obvious colonizing behavior. Future trials to characterize phenotypic variation of plants cultivated in typical horticultural landscapes would help us understand its aesthetic value as a landscape plant. Bog birch is well-suited to clonal propagation and grows vigorously in nursery containers, indicating that it is amenable to commercial production.

Speakers

Jessica Hutchinson

University of Maine

Co-authors

Bryan Peterson

University of Maine

Thursday September 26, 2024 3:00pm - 3:10pm HST
Nautilus

Poster presentation (individual talk), Propagation

SUBJECT Propagation

3:10pm HST

PROP - Propagating Pomegranate Through Hardwood and Softwood Cuttings

Thursday September 26, 2024 3:10pm - 3:20pm HST

Nautilus

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

PRAKRITI NEPAL

Utah State Univeristy

Co-authors

Asmita Paudel

Utah State University

Benjamin Scow

Utah State University

Youping Sun

Utah State Univeristy

Zirui Wang

Utah State University

Thursday September 26, 2024 3:10pm - 3:20pm HST
Nautilus

Poster presentation (individual talk), Propagation

SUBJECT Propagation

3:20pm HST

PROP - Identifying Patterns of Clone Degeneration to Improve Diagnostics.

Thursday September 26, 2024 3:20pm - 3:30pm HST

Nautilus

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

Thomas Gradziel

University of California

Thursday September 26, 2024 3:20pm - 3:30pm HST
Nautilus

Poster presentation (individual talk), Propagation

SUBJECT Propagation

3:30pm HST

PROP - Evaluating Leaf Cutting Success for Achimenes Propagation

Thursday September 26, 2024 3:30pm - 3:40pm HST

Nautilus

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

Chad Miller

Assistant Professor; Department of Horticulture and Landscape, Colorado State University

Thursday September 26, 2024 3:30pm - 3:40pm HST
Nautilus

Poster presentation (individual talk), Propagation

SUBJECT Propagation

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

South Pacific 3

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

Srijana Thapa Magar

Kentucky State University

Co-authors

Cristina Pisani

USDA-ARS

Thursday September 26, 2024 4:45pm - 4:55pm HST
South Pacific 3

Poster presentation (individual talk), Temperate Tree Nut Crops 1

SUBJECT Temperate Tree Nut Crops

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

South Pacific 3

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

GURREET BRAR

california state university

Co-authors

Faranak Hadavi

california state university

Masood Khezri

MR Institute

Vishvanathan Krishnan

california state university

Thursday September 26, 2024 4:55pm - 5:05pm HST
South Pacific 3

Poster presentation (individual talk), Temperate Tree Nut Crops 1

SUBJECT Temperate Tree Nut Crops

5:05pm HST

NUTS/HPRB - Water requirements of pecan orchards in the Southeast U.S.

Thursday September 26, 2024 5:05pm - 5:15pm HST

South Pacific 3

The state of Georgia is one of the states leading in pecan production in the U.S. However, the seminal papers on water management using state-of-art techniques like eddy-covariance system and micro lysimeters are far and few. Much of the information available on water-use efficiency arises from earlier studies done in the Southwest. However, crop varieties, Georgia soils, and rainfall, when coupled with a long, hot and humid climate of the Southeast, lead to contrasting water management practices from that of the Southwest. The present paper addresses the water needs of pecans in trees six to ten-year old throughout different physiological stages of the orchard in Georgia using the current irrigation schedule. Several record-breaking temperatures and the shifting rainfall patterns have had an important impact on pecan production. This precipitation variability further exacerbates the needs to tailor water-use efficiency to these new normal conditions. Along with the in situ meteorological data and soil moisture information, an eddy-covariance system is installed in Hawkinsville, Georgia. This poster shows how southeastern pecan orchards have different water requirements for optimum yield. This paper focuses on the differences between the current schedule, irrigation application at the farm and water-use data from the present study. Such results obtained likely for the first time will help to devise water management practices, optimize irrigation scheduling leading to increased water conservation and yield.
Keywords: water-use efficiency, production, climate change

Speakers

Poster presentation (individual talk), Temperate Tree Nut Crops 1

SUBJECT Temperate Tree Nut Crops