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Monday, September 23
 

9:00am HST

 
Tuesday, September 24
 

10:14am HST

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

Stephen Meyers

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

10:15am HST

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

Te Ming Tseng

Mississippi State University
Co-authors
AC

Aricia Correa Ritter

Mississippi State University
NA
BB

Bailey Bullard

Mississippi State University
NA
DE

Dante Ellias

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

10:30am HST

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

Sandra Branham

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

10:45am HST

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

Peter Dittmar

University of Florida
Co-authors
DT

Danielle Treadwell

University of Florida
NA
GM

Gabriel Maltais-Landry

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

11:00am HST

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

Stephen Meyers

Purdue University
Co-authors
CL

Carlos Lopez Manzano

Purdue University
NA
CC

Celia Corado Mendoza

Purdue University
NA
EC

Emmanuel Cooper

Purdue University
NA
JA

Jeanine Arana

Purdue University
JC

Josue Cerritos

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

11:15am HST

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

Samuel Wortman

University of Nebraska - Lincoln
Co-authors
CW

Caleb Wehrbein

University of Nebraska - Lincoln
CP

Chris Proctor

University of Nebraska - Lincoln
NA
CR

Claudio Rojas

University of Costa Rica
NA
EJ

Elizabeth Jeske

University of Nebraska - Lincoln
NA
IK

Ignatius Kadoma

3M Company
NA
LD

Lisa Durso

USDA ARS
NA
MU

Manuel Umana

University of Costa Rica
NA
ML

Mia Luong

University of Nebraska-Lincoln
NA
RD

Rhae Drijber

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

11:30am HST

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

Ramdas Kanissery

University of Florida
Co-authors
RT

Ruby Tiwari

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

11:59am HST

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

Zelalem Mersha

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

12:00pm HST

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

Hannah Voye

South Dakota State University
Co-authors
KL

Kristine Lang

South Dakota State University
RB

Rhoda Burrows

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

12:10pm HST

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

Zelalem Mersha

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

12:20pm HST

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

Richard Noel Torres

University of Missouri - Columbia
Co-authors
RS

Reid Smeda

University of Missouri - Columbia
NA
XX

Xi Xiong

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

12:30pm HST

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

Jeanine Arana

Purdue University
Co-authors
SM

Stephen Meyers

Purdue University
WG

Wenjing Guan

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

12:40pm HST

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

Albert Adjesiwor

University of Idaho
Co-authors
AS

Andre Simoes Araujo

Colorado State University
NA
CA

Clarke Alder

Amalgamated Sugar
NA
JF

Joel Felix

Oregon State University
NA
TG

Todd Gaines

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

12:50pm HST

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

Pawel Petelewicz

University of Florida
Co-authors
AB

Agustin Boeri

Texas A
NA
BU

Bryan Unruh

University of Florida
NA
CM

Chase McKeithen

University of Florida
NA
JG

Jayson Ging

University of Florida
NA
KG

Katarzyna Gawron

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

1:00pm HST

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

Pawel Petelewicz

University of Florida
Co-authors
AS

Arnold Scumann

University of Florida
NA
GM

Gregory MacDonald

University of Florida
NA
MS

Marco Schiavon

University of Florida
NB

Nathan Boyd

University of Florida
NA
QZ

Qiyu Zhou

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

1:10pm HST

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

Tyler Campbell

Clemson University
Co-authors
GS

Gursewak Singh

Clemson University
KG

Karla Gage

Southern Illinois University
NA
LS

Lynn Sosnoskie

Cornell University
NA
MF

Michael Flessner

Virginia Tech Univ
NA
PW

Philip Wadl

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

1:20pm HST

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

Carly Strauser

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

Ajay Nair

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

1:30pm HST

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

Rupinder Saini

Texas Tech University
Co-authors
CT

Calvin Trostle

Texas And M Agrilife
NA
JM

Jasleen Makkar

Texas Tech University
NA
PB

Preetaman Bajwa

Texas Tech University
NA
SS

Sukhbir Singh

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

1:40pm HST

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

Kathryn Fontenot

LSU AgCenter
Co-authors
AH

Alessandro Holzapfel

Louisiana State University Agricultural Center
GL

Gabriel LoCoco

LSU AgCenter
NA
HK

Heather Kirk Ballard

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

Reeve Legendre

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

2:15pm HST

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

Moderator
NB

Natalie Bumgarner

Assistant Professor, University of Tennessee Knoxville
Speakers
AF

Amy Fulcher

University of Tennessee
MV

Margarita Velandia

The University of Tennessee
NA
JS

Jacob Shreckhise

USDA-ARS, U.S. National Arboretum
avatar for Di Hu

Di Hu

CEO, moss robotics inc.
SS

Shrijit Singh

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

4:29pm HST

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

Erin Silva

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

4:30pm HST

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

Brenton Breland

Mississippi State University
Co-authors
CC

Christine Coker

Mississippi State University
RS

Ronald Stephenson

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

4:45pm HST

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

Erin Silva

UW-Madison
Co-authors
DH

Daniel Hayden

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

5:00pm HST

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

Lane Selman

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

5:15pm HST

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

Kathleen Delate

Iowa State University
Co-authors
JP

Josiah Pollock

Iowa State University
NA
KP

Karenna Petersen

Iowa State University
NA
RT

Robert Turnbull

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

5:30pm HST

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

Jashanpreet Kaur

The University of Georgia
Co-authors
JH

Joon Hyuk Suh

The University of Georgia
NA
KC

Kate Cassity Duffey

The University of Georgia
NA
TC

Timothy Coolong

The University of Georgia
Tuesday September 24, 2024 5:30pm - 5:45pm HST
Lehua Suite
 
Wednesday, September 25
 

7:59am HST

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

Moderator
JC

Juan Carlos Diaz Perez

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

8:00am HST

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

Caleb Wehrbein

University of Nebraska - Lincoln
Co-authors
SW

Samuel Wortman

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

8:15am HST

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

Tricia Jenkins

Kansas State University
Co-authors
AM

Amrita Mukherjee

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

Cary Rivard

Kansas State University
EP

Eleni Pliakoni

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

8:30am HST

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

Nayab Gull

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

8:45am HST

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

Juan Carlos Diaz Perez

University of Georgia
Co-authors
MB

Mamata Bashyal

University of Massachussets
YK

Yamin Kabir

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

9:00am HST

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

Jeffrey Bates

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

9:29am HST

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

Patrick Conner

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

9:30am HST

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

Bailey Rayfield

University of Georgia
Co-authors
LW

Lenny Wells

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

9:45am HST

NUTS 1 - Leaf Anatomical Traits and Water Use Efficiency in Four Pecan Cultivars
Wednesday September 25, 2024 9:45am - 10:00am HST
The leaf surface and interior structure can affect photosynthesis and transpiration rates associated with water use efficiency. Several studies have assessed pecan (𝘊𝘢𝘳𝘺𝘢 𝘪𝘭𝘭𝘪𝘯𝘰𝘪𝘯𝘦𝘯𝘴𝘪𝘴) leaf anatomical traits and established differences between cultivars; however, the effect of these traits on water use efficiency across cultivars has not been established. Understanding the relationship between leaf anatomical structures and water use efficiency across pecan cultivars allows for the identification of those that are well suited for water limited environments. In this study, we examined the leaf mesophyll layer thickness (µm), trichome density (trichome mm⁻²), stomatal density (stomata mm⁻²), and stomatal pore area (µm²) of four pecan cultivars (‘Wichita’, ‘Western’, ‘Pawnee’, and ‘Lakota’; all grafted to clonally propagated rootstocks). Leaves were collected at the NMSU Leyendecker Plant Science Research Center, and their cross-section and abaxial surface were imaged using light and scanning electron microscopy, respectively. ‘Lakota’ leaves had the thinnest palisade mesophyll layer and thickest spongy mesophyll layer relative to total leaf thickness. The stomatal density of ‘Pawnee’ was significantly less than the other cultivars, but no significant differences in stomatal pore area were observed. Intrinsic water use efficiency, calculated as ratio of the carbon assimilation rate to stomatal conductance to water vapor, was obtained using a leaf gas exchange meter on three separate days. A stable carbon isotope composition analysis was also conducted to provide insight into the leaf’s longer-term water use efficiency. The results showed that the intrinsic water use efficiency of ‘Lakota’ was different from ‘Western’ on one of the days; however, differences between cultivars were not significant when averaged across the measurement dates. Furthermore, the relative ¹³C abundance and ¹³C discrimination did not have significant differences across the four pecan cultivars evaluated, suggesting that differences in leaf anatomical traits did not influence the water use efficiency of these samples.
Speakers
SB

Sarahi Bracamontes

New Mexico State University
Co-authors
CV

Ciro Velasco-Cruz

New Mexico State University
NA
JR

Jennifer Randall

New Mexico State University
NA
KG

Kanchan Grover

New Mexico State University
NA
RH

Richard Heerema

New Mexico State University
NA
SB

Samy Belteton

New Mexico State University
NA
Wednesday September 25, 2024 9:45am - 10:00am HST
Lehua Suite

10:00am HST

NUTS 1 - Performance of Five Early-harvest Pecan Cultivars in South Georgia
Wednesday September 25, 2024 10:00am - 10:15am HST
Five pecan (Carya illinoinensis) cultivars were evaluated over 15 years in a trial at Tifton, GA, USA. Trialed cultivars included the standard early cultivar Pawnee, and the more recent releases Byrd, Morrill, Lakota, and Treadwell. Actual yield were measured for each tree each year and a 50-nut sample was taken to determine nut quality. Trees were evaluated for leaf and nut scab infection (Venturia effusa) and black aphid (Melanocallis caryaefoliae) damage. ‘Pawnee’ yielded significantly less than all the newer cultivars which had similar cumulative yields. However, ‘Byrd’, ‘Lakota’, and ‘Treadwell’ had significantly more yield alternation than ‘Pawnee’ and ‘Morrill’, with reduction of nut quality in the “ON” years. ‘Pawnee’ was the earliest cultivar and produced excellent quality nuts, but yields were mediocre. ‘Lakota’ had excellent scab resistance, but overcropped resulting in inferior quality, and should only be grown in orchards were crop loads are controlled by hedging or tree shaking. ‘Byrd’ and ‘Treadwell’ are very scab susceptible and also need crop load control, making them poorly suited for south Georgia. ‘Morrill’ had consistent cropping and excellent nut quality but is also very scab susceptible and should only be grown with excellent disease management practices.
Speakers
PC

Patrick Conner

University of Georgia
Wednesday September 25, 2024 10:00am - 10:15am HST
Lehua Suite

10:15am HST

NUTS 1 - Enhancing Pecan Tree Resilience Against Spring Freeze Events: Insights from Secondary Bud Dynamics and Carbohydrate Analysis
Wednesday September 25, 2024 10:15am - 10:30am HST
Pecan growers face significant challenges in protecting their crops from the spring freezes that devastate yields. Conventional freeze protection methods are impractical for the large, tall trees. This study investigated the dynamics of the secondary bud break in pecan trees, a mechanism that ensures yield when primary buds are damaged. In three pecan cultivars ('Pawnee,' 'Kanza,' and 'Maramec') we characterized the sprouting potential of secondary buds after the primary buds were cold damaged. Primary bud shoots were collected at three different bud growth stages: outer bud scale shed stage, inner bud scale shed stage, and early bloom stage. The shoot samples held at 6°C to terminate primary buds’ growth. The cold treated shoots were then held in growth chambers set to mimic spring humidity, temperature, and light conditions. The percentage of branches with secondary bud break was recorded. The carbohydrate levels (sugar and starch) were measured in the apical shoots treated at the outer bud scale shed stage. The results showed variation among cultivars in the number of shoots with secondary buds and the stage at which primary buds were terminated. The ‘Kanza’ and ‘Pawnee’ cultivars produced more secondary buds when the primary buds were cold damaged in the outer bud scale shed stage. The ‘Maramec’ cultivar produced more secondary buds when the primary buds were cold damaged in the inner bud scale shed stage. The A carbohydrate analysis of the three cultivars demonstrated a correlation between successful secondary bud break and elevated carbohydrate levels in the one-year-old shoots. Cultivars with higher secondary bud break rates, 'Kanza' and 'Pawnee', had higher carbohydrate levels than 'Maramec.' These findings suggest that higher carbohydrate levels in one-year-old shoots facilitate successful secondary bud break following spring freeze damage to primary buds. This research suggests developing production practices to improve tree carbohydrate levels in the late summer and fall could potentially protect pecan production from spring freeze damage.
Speakers
LZ

Lu Zhang

Oklahoma State University
Co-authors
AK

Amandeep Kaur

Oklahoma State University
NA
JM

Justin Moss

Oklahoma State University
NA
LF

Louise Ferguson

University of California, Davis
NA
NM

Niels Maness

Oklahoma State University
NA
YS

Yanwei Sun

Oklahoma State University
NA
Wednesday September 25, 2024 10:15am - 10:30am HST
Lehua Suite

10:30am HST

NUTS 1 - Biochar in Pecan Orchards: Unraveling Water Stress Dynamics for Sustainable Irrigation Management
Wednesday September 25, 2024 10:30am - 10:45am HST
Pecan orchards in the southwestern United States face significant challenges due to persistent drought conditions that adversely affect yield and nut quality. Pecans are recognized as the most water-intensive crop in the region, and therefore require innovative strategies to optimize the available irrigation water. This study explores the use of pecan wood-derived biochar as a soil amendment to enhance the soil water-holding capacity and alleviate water stress in pecan orchards. We conducted field experiments during the summer of 2023 in a flood-irrigated pecan orchard located in the Mesilla Valley, New Mexico, USA. We accounted for the irrigation gradient in a flood-irrigated orchard by using a randomized complete block design with four blocks, each containing three equidistant trees from the irrigation valves. The trees within each block were randomly assigned to one of three biochar application rates: 0 kg/ha (treated area), 6300 kg/ha, and 12600 kg/ha. The treated area was situated within the herbicide strip, spanning 9.14 m in length – centered on the tree – with 1.22 m on either side of the tree. To assess tree water status, two leaf samples from the lower shaded canopy were covered in aluminum foil bags for a minimum of 15 minutes before mid-day stem water potential was measured. Mid-day stem water potential was measured throughout the growing season near the end of each irrigation dry-down cycle. For each tree, we calculated the average mid-day stem water potential and then performed an ANOVA to compare the averages across the treatment groups. In the five months after biochar application, there were no significant differences in tree water status across the treatment groups. This highlights the need for more research to study the interactions among soil moisture content, biochar amendment applications, and pecan tree mid-day stem water potential. This study contributes to the ongoing discourse that calls for enhancing crop water use efficiency in arid regions by providing a foundation for future studies that seek to use biochar as a sustainable agricultural practice in pecan orchards.
Speakers
JM

Jamin Miller

New Mexico State University
Co-authors
AF

Alexander Fernald

New Mexico State University
NA
CV

Ciro Velasco-Cruz

New Mexico State University
NA
DD

David Dubois

New Mexico State University
NA
JI

John Idowu

New Mexico State University
NA
RH

Richard Heerema

New Mexico State University
NA
Wednesday September 25, 2024 10:30am - 10:45am HST
Lehua Suite

10:45am HST

NUTS 1 - Evaluating Soil Management Impacts on the Pecan Orchard Mycobiome in the Semi-Arid Southwestern United States
Wednesday September 25, 2024 10:45am - 11:00am HST
Pecans hold significant agricultural importance in the water-limited Southwestern United States, underscoring the need for sustainable soil management practices in pecan cultivation. Recognizing the intricate relationship between soil treatments and the soil microbiome is essential to develop effective orchard soil management strategies. Soil fungi, particularly root-associated mycorrhizal fungi, are vital in facilitating water and nutrient uptake, protecting against pathogens, and enhancing overall orchard health and productivity. Soil management may impact the fungal community composition of Southwestern pecan orchard soils. Various soil management strategies are implemented in pecan orchards, including varying soil cover or applying mycorrhizal and bacterial inoculants. These techniques alter the soil environment, which may change the soil fungal biodiversity. This study investigates the impact of diverse soil management techniques on the soil mycobiome within a twelve-year-old ‘Pawnee’ pecan orchard in New Mexico. In a randomized complete block design, eight treatments of various soil cover – bare soil, cover crops, compost, or a combination of cover crops and compost – each either with or without mycorrhizal and bacterial inoculants, were applied to evaluate their effects on soil fungal diversity. Laboratory analyses, including DNA extraction, PCR amplification, and Illumina sequencing, were performed, alongside physiochemical testing for soil pH, electrical conductivity, and mineral nutrient content. The resulting sequence data were analyzed to provide insights into the complex interactions between soil management practices and microbial communities. Sampling conducted during the 2022 Spring and harvest seasons revealed significant differences in alpha and beta diversity between roots and bulk/rhizosphere soil (P < 0.10). Significant differences in alpha and beta diversity of fungi based on treatment were also observed, highlighting the potential influence of soil management practices, including soil cover and inoculant use, on fungal community composition. Our study offers valuable insights into the temporal changes in the community structure of pecan orchard fungi when treated with different soil amendments. Understanding how soil management practices influence the soil mycobiome can inform more sustainable pecan cultivation practices. By optimizing soil management strategies to support beneficial fungal communities, growers may enhance soil health, water and nutrient availability, and plant resilience to environmental stress.
Speakers
avatar for McKenzie Stock

McKenzie Stock

New Mexico State University
Co-authors
CV

Ciro Velasco-Cruz

New Mexico State University
NA
JR

Jennifer Randall

New Mexico State University
NA
NP

Nicole Pietrasiak

University of Nevada Las Vegas
NA
PG

Paul Gabriel

New Mexico State University
NA
RH

Richard Heeremaa

New Mexico State University
NA
Wednesday September 25, 2024 10:45am - 11:00am HST
Lehua Suite

11:14am HST

Undergraduate Student (UG)
Wednesday September 25, 2024 11:14am - 12:45pm HST
A Comparative Study Analyzing Light Lengths for the Growth of Rex Butterhead Lettuce Utilizing GREENBOX Technology - Mya Griffith
Evaluating the Feasibility of Lettuce Crop Cultivation with Reclaimed Water Utilizing GREENBOX Technology - Mya Griffith
The Assessment of Different Growth Mediums for Plug Cultivation in a Controlled Environment - George Buss
Comparative Analysis of Lettuce Growth Using Compost Versus Conventional Soil - Sofia Huber
Feasibility of Plug Production Utilizing Digestate From Home Water-Energy-Food Systems (H-WEF) - Rory Dunn
From Flower to Fruit: Growing Degree Days and Peach Ripening - Matthew Almy
Enhancing rose propagation using moisture sensor-controlled irrigation and LED supplemental lighting in greenhouses - Braylen Thomson
Wednesday September 25, 2024 11:14am - 12:45pm HST
Lehua Suite

11:15am HST

UG - Evaluating the Feasibility of Lettuce Crop Cultivation with Reclaimed Water Utilizing GREENBOX Technology
Wednesday September 25, 2024 11:15am - 11:30am HST
The development of GREENBOX technology addresses the challenges posed by rapid population growth, which intensifies the demand for agricultural resources essential for cultivating and distributing fresh produce, including arable land, water, and nutrients, to both rural and urban areas. Utilizing principles of Controlled Environment Agriculture (CEA), GREENBOX technology optimizes growth conditions for leafy green crops by leveraging existing urban infrastructure and readily available commercial equipment. GREENBOX technology allows for precise control over environmental variables such as temperature, humidity, light intensity/spectrum, and nutrient delivery, thereby enhancing the growth performance of leafy greens. We were interested in assessing the feasibility of utilizing reclaimed water for crop production as preliminary experiments employing GREENBOX technology that employed a standard nutrient solution comprising a blend of 5-12-26 and 15-0-0 Calcium Nitrate for crop production. This study's primary objective was to conduct a comparative analysis of Lactuca sativa Rex Butterhead Lettuce production using the standard nutrient solution as the control (Treatment 1), and Reclaimed water or treated wastewater supplemented with additional nutrients (Treatment 2). The assessment focused on measuring crop biomass and productivity and environmental conditions associated with each nutrient solution to identify any significant differences. Biomass parameters, including wet weight, dry weight, leaf area, leaf count, and chlorophyll concentration, were measured alongside derived data such as Leaf Area Index (LAI), Specific Leaf Area (SLA), and biomass productivity. Statistical analysis of the biomass data was conducted to discern differences in biomass parameters between crop growth using both hydroponic solutions. Both treatments yielded Rex Butterhead lettuce well above the anticipated harvest weight of 180g, indicating their suitability for crop production in urban warehouse settings. The findings of this experiment contribute valuable insights into the feasibility of utilizing various types of wastewater for hydroponic crop growth. Future experiments employing GREENBOX technology may utilize these findings to enhance the efficiency, productivity, and sustainability of GREENBOX units. This study has impactful implications for sustainability, as it offers a potential solution to mitigate water scarcity and promote efficient resource utilization in agricultural practices. Keywords: CEA, Hydroponics, lettuce, Reclaimed Wastewater, urban agriculture
Speakers
MG

Mya Griffith

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
BR

Barry Rosen

Florida Gulf Coast University
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
GB

George Buss

Florida Gulf Coast University
JG

John Griffis

Florida Gulf Coast University
NA
KJ

Kathryn Jackson

Independent Researcher
NA
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 11:15am - 11:30am HST
Lehua Suite

11:30am HST

UG - The Assessment of Different Growth Mediums for Plug Cultivation in a Controlled Environment
Wednesday September 25, 2024 11:30am - 11:45am HST
Plugs are crucial for starting crop production in greenhouses, soil, and controlled environment agriculture (CEA). Horticultural, vegetable, fruiting, and ornamental crops that utilize plugs for production have demonstrated better plant health, transplant establishment rate, and total yield. Many substances are capable of supporting plug growth, so the APS Laboratory for Sustainable Food at Florida Gulf Coast University investigated the quality of plugs prepared based on different commonly used growth mediums for plug production. We carried out the growth of Rex Butterhead Lettuce Latuca Sativa plugs with six different treatments: 1) Rockwool, 2) Oasis® Horticube, 3) Perlite 4) Coco Coir, 5) Phenolic Foam, and 6) Peat Pellets. The seeds were sowed in their respective growth medium and watered every day. The plugs were then cultivated for 15 days in a controlled environment until two leaves apart from the cotyledon had developed. After 15 days, we collected data which included wet weight (g), dry weight (g), leaf area (cm2), nitrogen content (mg/g), and chlorophyll concentration (mg/cm2). In addition, we derived data including the Leaf Area Index (LAI) and Specific Leaf Area (SLA, cm2/g). Descriptive statistics were used to describe the biomass data. Pairwise permanovas were conducted, followed by pairwise Wilcoxon tests to determine which treatments result in significant differences for each response variable. A permutation MANOVA revealed a significant treatment effect on plug preparation (p=0.001). All subsequent multilevel pairwise comparisons were significant, with the exception of phenolic foam vs perlite (p=0.294). Of all the treatments, we concluded that plugs grown in Peat Pellets produced the most viable plugs with the largest wet weight (g), dry weight (g), and total leaf area (cm2). Results from this study may inform growers about appropriate growth mediums for efficient plug production. Keywords: Controlled Environments, Growth Mediums, Lettuce, Plugs, Urban Agriculture
Speakers
GB

George Buss

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
JL

John L Griffis

Florida Gulf Coast University
NA
KJ

Kathryn Jackson

Independent Researcher
NA
MG

Mya Griffith

Florida Gulf Coast University
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 11:30am - 11:45am HST
Lehua Suite

11:45am HST

UG - Comparative Analysis of Lettuce Growth Using Compost Versus Conventional Soil
Wednesday September 25, 2024 11:45am - 12:00pm HST
Conventional agricultural techniques have been degrading American soils nationwide since the beginnings of modern-day agriculture through practices such as soil tilling, using nitrogen synthetic fertilizers, and monocultural systems. These previously mentioned techniques contribute to degrading soil health, mass emissions of carbon dioxide into the atmosphere, and decreased biodiversity. Regenerative agriculture offers a combination of sustainable practices that will create carbon sinks to sequester atmospheric carbon dioxide, restore national food systems, and prioritize soil health. Regenerative agriculture techniques include the utilization of cover crops, compost, no-tillage, mob grazing, and polyculture. The APS Laboratory for Sustainable Agriculture focused on the effectiveness of compost by comparing the growth of lettuce in four different treatments: 100% compost (100%C), 75% compost 25% Miracle-Gro (75%C-25%MG), 50% compost 50% Miracle-Gro (50%C-50%MG), and finally, 100% Miracle-Gro (100%MG). The lettuce seeds were kept in a growth tent for 15 days during their period of germination before being transferred to four 1x1 meter plots in the Food Forest at Florida Gulf Coast University (FGCU) for the 60-day growth period. The lettuce crops grew to full bloom and ready for harvest. Sampling events took place every six days in which crop growth data including wet weight (g), dry weight (g), chlorophyll concentration (μmol/m^2), and leaf area (cm^2) were collected. Specific Leaf Area (g/cm^2) and Leaf Area Index were derived, and statistical analysis was conducted. Based on the statistical tests conducted at the 5% significance level using R statistical software, soil treatment type was found to be significant (p=0.0002). Soil treatment type was shown to have significantly impacted wet weight (p
Speakers
SH

Sofia Huber

Florida Gulf Coast University
Wednesday September 25, 2024 11:45am - 12:00pm HST
Lehua Suite

12:00pm HST

UG - Feasibility of Plug Production Utilizing Digestate From Home Water-Energy-Food Systems (H-WEF)
Wednesday September 25, 2024 12:00pm - 12:15pm HST
The integration of sustainable technologies in waste management systems has become imperative in addressing the escalating challenges of agricultural productivity and sustainability. Plugs are essential when starting crop production in controlled environment agriculture (CEA) setups and greenhouses. Horticultural crops such as vegetables, fruiting, and ornamental plants that utilize plugs have demonstrated higher success rates, healthier plants, and higher total yields. The APS Laboratory for Sustainable Agriculture at explored the innovative utilization of digestate from the Home Water-Energy-Food Systems (H-WEF), the H-WEF system converts household food waste into biogas, electricity, and nutrient-rich digestate. The digestate from the H-WEF system was used to produce agricultural plugs, presenting a novel approach to circular resource utilization. We carried out the growth of Rex Butterhead Lettuce Latuca Sativa plugs with eight different treatments, 1) control synthetic fertilizer; 2) 5% Digestate – 95% RO Water (5D–95RO); 3) 10% Digestate – 90% RO Water (10D–90RO); 4) 15% Digestate – 85% RO Water (15D–85RO); 5) 20% Digestate – 80% RO Water (20D–80RO); 6) 25% Digestate – 75% RO Water (25D–75RO); 7) 30% Digestate – 70% RO Water (30D–70RO); 8) 35% Digestate – 65% RO Water (35D–65RO). The seeds were sowed with their fertigation treatment and watered every day. The plugs were cultivated for 15 days in a controlled environment until two leaves had developed after the cotyledon. After 15 days, we collected data on wet weight (g), plug head area (cm2), total leaf area (cm2), total nitrogen content (mg/g), total chlorophyll content (mg/cm2), and dry weight (g). In addition, we collected data on the Leaf Area Index (LAI, cm2/cm2) and Specific Leaf Area (SLA, cm2/g). The synthetic fertigation yielded a higher wet weight than the following treatments: 5D–95RO, 10D–90RO, and 35D–65RO. While the 30D–70RO treatment produced a larger plug head than all other treatments. The digestate-based fertilizers were comparable to the synthetic fertilizer at dilutions of 25D–75RO and 30D–70RO. Results from this study may inform growers about the viability of utilizing digestate for plug production.
Speakers
RD

Rory Dunn

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
JG

John Griffis

Florida Gulf Coast University
NA
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
ST

Seneshaw Tsegaye

Florida Gulf Coast University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 12:00pm - 12:15pm HST
Lehua Suite

12:15pm HST

UG - From Flower to Fruit: Growing Degree Days and Peach Ripening
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Anticipating crop advancement, particularly fruit maturation, is critical for peach growers' success and marketing. Growing Degree Days (GDD) predict the growth and development stages of plants and insects. They are based on the accumulation of heat units above a specific baseline temperature, under the concept that a certain amount of heat is needed to develop from one stage to another in the life cycle. GDDs are used for various purposes in agriculture and horticulture, such as planting scheduling, pest management and crop monitoring. Peach growers use GDD to predict the peach cultivar maturity and schedule harvesting. However, peach cultivars' ripening time is reported in the calendar or Julian days (JD) or as the number of days before or after a reference cultivar, which is not amenable to climate change. Therefore, we modeled GDD in a diverse set of peach and nectarine cultivars and breeding accessions using the Baskerville-Emin (BE) method. The GDD was calculated from full bloom to fruit maturity using historical temperature, bloom and ripening data collected at the Musser Fruit Research Station in Seneca, South Carolina, in the 2017-2023 period. GDD and JD variability will be presented, and implication of providing GDD information on existing and newly released cultivars for producers and researchers will be discussed.
Speakers
MA

Matthew Almy

Clemson University
NA
Co-authors
JM

John Mark Lawton

Clemson University
NA
KG

Ksenija Gasic

Clemson University
Wednesday September 25, 2024 12:15pm - 12:30pm HST
Lehua Suite

12:30pm HST

UG - Enhancing rose propagation using moisture sensor-controlled irrigation and LED supplemental lighting in greenhouses
Wednesday September 25, 2024 12:30pm - 12:45pm HST
This study addresses the critical need for precise irrigation management in the greenhouse production of high-value ornamental crops, focusing on the propagation of single-stem rose (Rosa rubiginosa) cuttings under light-emitting diode (LED) supplemental lighting. The current lack of effective monitoring and control systems for substrate moisture poses challenges in optimizing plant growth while minimizing water and nutrient losses. In this context, we propose the integration of moisture sensors for real-time monitoring and control of substrate moisture levels, coupled with LED supplemental lighting, to enhance the production of rose cuttings. Our approach involved assessing the feasibility and effectiveness of moisture sensor-controlled irrigation in greenhouses, considering the specific requirements of rose propagation and the influence of LED lighting on plant growth. We tested three Ө thresholds (0.25, 0.35, and 0.45 m3.m-3) and five light levels as supplemental lighting (100, 175, 250, 325, and 400 µmol.m-2.s-1) arranged on randomized complete block design with four replications. Rose Double Knock Out® ‘Radtko’ PP 16,202 CPBR 3,104 plants were grown in 15.6 L pots (Pioneer Pots; Blackmore Co., Belleville, MI) filled with 20% Canadian peat/58% aged pine/10% perlite/12% EZ Hydrafiber lime potting mix (Oldcastle HFC25; Oldcastle Lawn
Speakers
BT

Braylen Thomson

Undergrad Researcher, University of Georgia
Co-authors
AH

Alan Huber

University of Georgia
NA
BH

Brandon Heavern

James Greenhouses
NA
KJ

Ken James

James Greenhouses
NA
KQ

Kuan Qin

University of Georgia
LJ

Lars Jensen

Blackmore Company
NA
MH

Matthew Housley

University of Georgia
RF

Rhuanito Ferrarezi

University of Georgia
NA
Wednesday September 25, 2024 12:30pm - 12:45pm HST
Lehua Suite

12:45pm HST

UG - A Comparative Study Analyzing Light Lengths for the Growth of Rex Butterhead Lettuce Utilizing GREENBOX Technology
Wednesday September 25, 2024 12:45pm - 1:00pm HST
Exponential population growth adds increasing pressure on the agriculture industry to grow and distribute fresh foods to rural and urban areas, leading to the development of GREENBOX technology, which utilizes Controlled Environment Agriculture (CEA) principles to optimize the desired conditions for growth of leafy green crops. Using commercially available equipment, GREENBOX technology has the capability to be integrated into existing urban infrastructure to help relieve the negative impact urbanization has on the availability of fresh foods. GREENBOX technology allows environmental variables, such as temperature, humidity, light intensity/ spectrum, and nutrient delivery, to be controlled to enhance the growth performance of leafy greens. Precursory experiments using GREENBOX Technology utilized the standard photoperiod of 16 hours of light, and 8 hours of dark for all crop production. The main objective of this study was to conduct a comparative analysis of Lactuca sativa Rex Butterhead Lettuce production grown under different photoperiods using GREENBOX technology. Using the standard 16 hours of light and 8 hours of dark as the control, two different photoperiod treatments were tested. Treatment one consisted of a 14-hour light period and a 10-hour dark period, while treatment two consisted of a 12-hour light period and a 12-hour dark period. The biomass and productivity of the crops were measured in addition to the environmental conditions for each lighting regimen to ascertain any significant differences. The biomass parameters included wet weight (g), dry weight (g), leaf area (cm2), leaf count (n), and chlorophyll concentration (mg/cm2). We derived additional data, including the Leaf Area Index (LAI, cm2/cm2), Specific Leaf Area (SLA, cm2/g), and biomass productivity (kg/m2). A statistical analysis of the biomass data was used to understand the differences in biomass parameters between crop growth and different light lengths. No statistically significant differences were found between the biomass and productivity parameters for the 12-hour and 14-hour photoperiods. However, the weight weights, dry weights, Leaf Count, SLA, and LAI from the 16-hour photoperiod showed statistically significant differences from the 12 and 14-hour photoperiods. All treatments still produced Rex Butterhead lettuce above the expected harvest weight of 180g and are viable for crop production in urban warehouse settings. The results of this experiment may help us understand the relationship between photoperiod and the biomass performance of leafy greens. Future GREENBOX experiments may use this information to increase the efficiency and productivity outputs of GREENBOX units. Keywords: CEA, Hydroponics, lettuce, soilless agriculture, urban agriculture
Speakers
MG

Mya Griffith

Florida Gulf Coast University
Co-authors
AS

Ankit Singh

University of Maine
NA
BR

Barry Rosen

Florida Gulf Coast University
NA
GP

Galen Papkov

Florida Gulf Coast University
NA
GB

George Buss

Florida Gulf Coast University
JG

John Griffis

Florida Gulf Coast University
NA
KJ

Kathryn Jackson

Independent Researcher
NA
PC

Paige Carroll

Florida Gulf Coast University
NA
SB

Sarah Bauer

Mercer University
NA
XY

Xiusheng Yang

University of Connecticut
NA
Wednesday September 25, 2024 12:45pm - 1:00pm HST
Lehua Suite

1:59pm HST

Propagation (PROP)
Wednesday September 25, 2024 1:59pm - 3:45pm HST
Enhancing Germination of Silver Saw Palmetto (Serenoa repens form glauca): Water Uptake, Temperature, and Pre Sowing Treatment Effects - Vania Pereira
Propagation Strategies and Epigenetic Variations in Vaccinium Berry Crops - Samir Debnath
The Application Timing of a Cytokinin B-Mo-based Product Affects the Growth and Non-Structural Carbohydrates Contents of Cuttings During Adventitious Root Development - Mayra Toro Herrera
Characterizing the effects of PPFD and VPD during indoor acclimation of Chrysanthemum cuttings - Ana Sofia Gomez
Asexual Propagation of Salix humilis Using Dormant Hardwood Cuttings After Stock Plant Coppicing and Fungicide Application - Hazel Schrader
Evaluation of Auxin Application and the Presence or Absence of Roots or Inflorescences in the Propagation of Variegated Carex wahuensis subsp. wahuensis - Paulo Matos
Evaluating the Effect of Plant Growth Hormone Types and Rates on Osmanthus spp. Propagation - Yulong Chen
Evaluating Leaf Cutting Success for Achimenes Propagation - Chad T. Miller

Moderator
PM

Paulo Matos

University of Hawai'i
Wednesday September 25, 2024 1:59pm - 3:45pm HST
Lehua Suite

2:00pm HST

PROP - Enhancing Germination of Silver Saw Palmetto (Serenoa repens form glauca): Water Uptake, Temperature, and Pre Sowing Treatment Effects
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Silver saw palmetto is a native palm of the southeast coast of the United States that is of high ornamental value for native landscapes and commercial potential production due to its fruit’s phytotherapeutic properties. The main propagation method for this palm is seed-based germination, which has very slow and low germination rates. This study assessed imbibition rates, germination in different temperatures that simulated Florida seasons, and pre-sowing treatments. Diaspores were exposed to seeds within the endocarp, intact seeds, scarified seeds, and seeds with their operculum removed. The maximum fresh weight of saw palmetto seeds after imbibition was observed at 11 days. Significant differences in imbibition rates and final weight were noted for seeds with an endocarp, with lower fresh mass, and scarified seeds, which showed the highest rates. Summer temperatures consistently yielded the highest final germination percentage and uniformity for seeds with or without an endocarp on constant summer temperatures or move-along experiments throughout Florida seasons. Pre-sowing treatments, such as the removal of the operculum, proved to be highly efficient in promoting the highest germination percentages and rates, while seeds with an endocarp demonstrated lower and uneven germination. The application of hormones, particularly GA3 at 10,000 ppm, also showed promise in improving germination rates.
Speakers
VP

Vania Pereira

University of Florida
Co-authors
HP

Hector Perez

University of Florida
NA
JO

Jena Osmani

University of Florida
NA
TS

Thiago Souza Campos

UNESP - FCAV
NA
WV

Wagner Vendrame

University of Florida
NA
Wednesday September 25, 2024 2:00pm - 2:15pm HST
Lehua Suite

2:15pm HST

PROP - Propagation Strategies and Epigenetic Variations in Vaccinium Berry Crops
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Blueberry (Vaccinium sect. Cyanococcus Rydb.), lingonberry (V. vitis-idaea L.) and huckleberry (V. membranaceum; also called black huckleberry or black blueberry) are three important Vaccinium small fruit crops native to the North. They are valuable resources for bioactive components that play important roles in anti-oxidant, anti-tumor, anti-ulcer, and anti-inflammatory activities. They can be propagated to produce true-to-type plants either conventionally or by micropropagation. Propagation in vitro is now well accepted worldwide for commercial production of Vaccinium crops. Proficient plant propagation technique using shoot organogenesis and somatic embryogenesis was successfully established in blueberry and lingonberry. Shoot regeneration and proliferation in in-vitro conditions using various liquid bioreactors have successfully been achieved in various Vaccinium species. One of the major concerns in commercial production is the occurrence of variation in micropropagated plants. This presentation describes the in-depth progress of genetic and epigenetic variations in different Vaccinium species during micropropagation. It addresses different molecular techniques used to monitor true-to-type and epigenetics along with application of epigenetic variation in micropropagated Vaccinium berry crops. Keywords: blueberry, bioreactor micropropagation, DNA-methylation, huckleberry, molecular markers, lingonberry, somaclonal variation
Speakers
SD

Samir Debnath

St. John’s Research and Development Centre
Samir Debnath, Ph.D., P.Ag. Dr. Samir C. Debnath, a Research Scientist of Agriculture and Agri-Food Canada and an Adjunct Professor of Biology, Memorial University of Newfoundland, has authored and co-authored around 140 publications in peer-reviewed journals including review papers... Read More →
Co-authors
MS

Mehdi Sharifi

Summerland Research and Development Centre, AAFC, 4200 Highway 97, Summerland, British Columbia, Canada
Dr. Mehdi Sharifi is a “soil nutrient management” research scientist at Summerland Research and Development Centre in British Columbia, Canada. Before his current position, he was a professors at Trent and Dalhousie Universities. He completed two postdoctoral fellow positions... Read More →
RB

Rajesh Barua

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
SK

Sayani Kundu

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
SM

Sweety Majumder

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
US

Umanath Sharma

Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
NA
Wednesday September 25, 2024 2:15pm - 2:30pm HST
Lehua Suite

2:30pm HST

PROP - The Application Timing of a Cytokinin B-Mo-based Product Affects the Growth and Non-Structural Carbohydrates Contents of Cuttings During Adventitious Root Development
Wednesday September 25, 2024 2:30pm - 2:45pm HST
A large group of horticulture species are propagated vegetatively through shoot-tip cuttings harvested from stock plants and planted to form adventitious roots. Adventitious root development (ARD) leads to establishing a carbohydrate sink in the region of root regeneration, which is highly dependent on energy and carbon skeletons. We hypothesized that enhancing the source-to-sink relationship during ARD can lead to an efficient carbon allocation to growth, resulting in a well-rooted cutting. Thus, the research aimed to determine if the application time of a Cytokinin B-Mo-based product during the ARD of unrooted cuttings would impact the source-to-sink relationship and, hence, affect plug growth and quality. The product was applied at four application times plus a negative control as follows: T1: plants without product (control), T2: sticking stage (starting 24 h after the sticking); T3: callus formation stage; T4: root development stage; and T5: toning stage. The experiment was a complete randomized design with five treatments and 60 repetitions for treatment (n=60) in two experimental runs (n=120). The root and shoot length, the number of leaves, the leaf chlorophyll content, the root and shoot dry matter, and the root-to-shoot ratio were measured. Results indicate that applying the product at T2 in ARD's dedifferentiation and induction phase leads to the shortest root and shoot length, the lowest dry matter accumulation, and some phytotoxicity effects. For T3 in ARD's initiation phase, the application results in greater root, total dry matter, and total soluble sugar contents than the control. For T4 in ARD's expression phase, the application results in greater growth, total dry matter, and sucrose and starch contents than control and other treatments. Applying the product in T5 when the roots had grown and reached all the edges of the growing media did not have any benefit compared to the control. Our results suggest that the exogenous application of a product to strengthen the source-to-sink relationship during adventitious root development can potentially enhance the non-structural carbohydrate contents when applied at the root formation phase (T4), which correlates positively with the increase in the length and dry matter of the roots, generating a well-toned rooted cutting.
Speakers
avatar for Mayra Toro Herrera

Mayra Toro Herrera

Postdoctoral Research Associate, University of Connecticut
Co-authors
RR

Rosa Raudales

University of Connecticut
Wednesday September 25, 2024 2:30pm - 2:45pm HST
Lehua Suite

2:45pm HST

PROP - Characterizing the effects of PPFD and VPD during indoor acclimation of Chrysanthemum cuttings
Wednesday September 25, 2024 2:45pm - 3:00pm HST
During acclimation of unrooted cuttings (URC) under mist irrigation, the moisture status of URC is greatly affected by environmental conditions such as high photosynthetic photon flux density (PPFD) and vapor pressure deficit (VPD), both of which can cause rapid dehydration. The objective of this study was to characterize the effects of PPFD and VPD on indoor acclimation of Chrysanthemum ‘Olympia White’ URC. Cuttings were stuck in a peat-perlite substrate in propagation trays, placed under sole-source lighting in chambers where ultrasonic fog was used to automatically control relative humidity (RH). Mist irrigation was applied every 20 to 30 min for 3 h. Over 12 h, URC were exposed to 0, 35, 70, 80, 105, 140, or 210 µmol·m–2·s–1 PPFD and 70, 80, 90, or 100% RH setpoints, resulting in air VPD levels ranging from 0.02 to 0.59 kPa. In the chambers, there was a high level of environmental control, and PPFD did not affect air VPD (P = 0.712), which were therefore considered as independent climatic factors. Leaf temperature minus air temperature was considered an indicator of plant energy balance, where a warmer leaf than air temperature is a driver of evapotranspiration. Plant leaf temperature became cooler than the air temperature as air VPD increased (P = 0.024), likely caused by evaporative cooling of leaves. In contrast, increasing PPFD increased leaf temperature relative to air temperature, likely through radiant heating. Leaf VPD was positively correlated with air VPD (adjusted-R2 = 0.88) but was also affected by the interaction of PPFD and air VPD (P < 0.05). Two hours after misting was terminated (5 h total), some plants showed clear wilting especially under low RH. At 5 h, stomatal conductance and evapotranspiration of URC was increased by PPFD and decreased by air VPD (P < 0.01), although there was an interaction between PPFD and air VPD for stomatal conductance (P < 0.005). Further results highlighting responses to RWC, water uptake, and water loss will be presented.
Speakers
AS

Ana Sofia Gomez

Purdue University
Co-authors
CG

Celina Gomez

Purdue University
PF

Paul Fisher

University of Florida
NA
Wednesday September 25, 2024 2:45pm - 3:00pm HST
Lehua Suite

3:00pm HST

PROP - Asexual Propagation of Salix humilis Using Dormant Hardwood Cuttings After Stock Plant Coppicing and Fungicide Application
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Prairie willow (Salix humilis) is a naturally compact and adaptable shrub willow native to the eastern United States. This taxon has potential for use in managed landscapes because of its desirable habit, attractive flowers and foliage, and its purported tolerance to fluctuations in soil moisture. This adaptability could be advantageous for urban green infrastructure applications. However, unlike most willows, S. humilis is thought to exhibit recalcitrance to standard asexual propagation techniques. This recalcitrance is exacerbated by observed susceptibility to fungal infections that cause cutting mortality during propagation. Because juvenility can improve the rooting of propagules, we questioned whether stock plant rejuvenation (coppicing) and propagule treatment with fungicide would influence rooting and survival of S. humilis dormant hardwood cuttings. In February 2024, 300 full-length dormant stems were harvested at the USDA Plant Introduction Station in Ames, Iowa from stock plants that were either coppiced or not coppiced the previous year. Uniformly-sized basal cuttings were acquired by removing the proximal 23 cm of each stem. Experimental trials (N=300; n=75) evaluating the full factorial of stock plant status [non-coppiced (-coppice) or coppiced ( coppice)] and fungicide application [non-treated (-fungicide) or treated ( fungicide) by submerging propagules in T-Bird with 46.2% Thiophanate-methyl for 15 minutes] were conducted in a cool greenhouse at the University of Minnesota Horticultural Research Center in Chaska, MN. All cuttings were treated with 0.8% indole-3-butyric acid via Hormodin-3 Talc powder and stuck in 50 cell trays (5 × 5 × 12.5 cm cells) with a 1:1 perlite:bark-based media and placed on heat mats (22ºC) using a completely randomized design. Total number of propagules rooted, length of the longest three roots, and number of roots were recorded. Propagules were ranked on their overall rooting performance using a Likert Scale. Rooting percentage was 77%, 56%, 87%, and 69% for coppice/ fungicide, coppice/-fungicide, -coppice/ fungicide, and -coppice/-fungicide, respectively. Compared to the non-coppiced propagules, mean count of roots decreased by 41% for coppiced propagules, across fungicide applications. Compared to propagules not treated with fungicide, mean count of roots increased by 19% for propagules treated with fungicide, across coppice treatments. Future research will evaluate different types of cuttings to generate a complete vegetative propagation protocol for Salix humilis. This work supports the introduction of this versatile plant into commercial production, thereby augmenting the ornamental plant palette for challenging urban landscapes.
Speakers
HS

Hazel Schrader

Graduate Research Assistant, University of Minnesota Twin Cities
Co-authors
BM

Brandon Miller

University of Minnesota Twin Cities
Wednesday September 25, 2024 3:00pm - 3:15pm HST
Lehua Suite

3:15pm HST

PROP - Evaluation of Auxin Application and the Presence or Absence of Roots or Inflorescences in the Propagation of Variegated Carex wahuensis subsp. wahuensis
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Carex wahuensis subsp. wahuensis is an endemic Hawaiian species extensively used as a ground cover in landscaping and restoration. In recent years, a variegated form was identified and is now starting to be utilized in a handful of landscaping projects. While the green wild-type has been primarily propagated through seeds, protocols for single plant divisions are lacking and limits the commercialization and availability of the variegated form. In this study, we investigated the effect of indole-3-butyric acid (IBA) application as well as the presence or absence of roots and inflorescences on propagating single plant divisions of variegated C. wahuensis subsp. wahuensis. Container grown clumps were divided into single plantlets, with or without flowers and with or without roots (trimmed 7.6 to 10.2 cm length). For the first experiment, plantlets without flowers but with pre-existing roots were treated with or without 3000 ppm IBA and planted in 1:1 perlite and vermiculite. For the second experiment, plants with roots but with or without flowers, and plants without roots and flowers were also planted in 1:1 perlite and vermiculite. Both experiments were located on a mist bench, which activated every 2 minutes for 12 seconds, and both were allowed to root for up to 135 days. Root length and rooting index was recorded for the first experiment at 45 and 90 days after planting while rooting index was recorded for the second experiment at 45, 90 and 135 days after planting. Application of IBA did not improve root length and rooting index of plantlets. However, there was an observed difference in root length and rooting index between experimental runs. In the second experiment, plants with roots and no flowers exhibited the highest rooting index (3.3 = light rooting) followed by plants with no flowers and no roots (2.9 = alive but no roots to light rooting). Plants with flowers and roots exhibited the lowest rooting index (1.7 = mostly dead). Results of the study indicate that vegetative single plantlets of variegated Carex wahuensis subsp. wahuensis can be successfully rooted within 135 days after planting under mist.
Speakers
PM

Paulo Matos

University of Hawai'i
Co-authors
OB

Orville Baldos

University of Hawaii
Wednesday September 25, 2024 3:15pm - 3:30pm HST
Lehua Suite

3:30pm HST

PROP - Evaluating the Effect of Plant Growth Hormone Types and Rates on Osmanthus spp. Propagation
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Osmanthus is a genus of ornamental plants with valuable qualities such as pest resistance, evergreen foliage, and aromatic flowers. However, different species respond differently to growth hormones for propagation. This study aimed to evaluate the types and rates of plant growth hormones on different species of Osmanthus propagation. Six distinct Osmanthus species (Osmanthus heterophyllus ‘Kaori Hime’, Osmanthus armatus ‘Jim Porter’, Osmanthus x fortunei ‘Patty's Secret’, Osmanthus heterophyllus ‘Rotundifolius’, Osmanthus delavayi, and Osmanthus x fortunei ‘Fruitlandii’) were treated with Indole-3-butyric acid (IBA) powder, 500 mg/L and 2000 mg/L of Potassium Indole-3-butyric acid (K-IBA), 10% Kelpak (seaweed extract), and water dip (the control). The cuttings’ survival rates, rooting rates, callus rate and area, and root length were recorded. The results showed the O. heterophyllus ‘Kaori Hime’ exhibited the best survival and rooting rates, while the O. heterophyllus ‘Rotundifolius’ had the lowest survival rate, the O. armatus ‘Jim Porter’ had the highest callus quantity. Plants treated with IBA powder had significantly larger callus area than those seaweed treatments. In conclusion, O. x fortunei 'Fruitlandii' and O. heterophyllus 'Kaori Hime' exhibit superior performance in all six measurements compared to other plant species and are highly recommended. Conversely, O. delavayi and O. heterophyllus 'Rotundifolius' have displayed considerably weaker performance and are not recommended. Further research is necessary to determine the effectiveness of other propagation methods and treatments for Osmanthus.
Speakers
avatar for Yulong Chen

Yulong Chen

The University of Georgia
Co-authors
LC

Lilin Chen

The University of Georgia
NA
PY

Ping Yu

University of Georgia
Wednesday September 25, 2024 3:30pm - 3:45pm HST
Lehua Suite

4:29pm HST

Commercial Horticulture/ Federal Partners (CHEX/FP)
Wednesday September 25, 2024 4:29pm - 5:10pm HST
Advances in Phytophthora, Pythium, and Phytopythium Species Detection, Isolation, Culture, Diagnostics, and Virulence Rejuvenation - Timothy Waller
Effect of Planting Date on Strawberry Yield - Samantha Simard
Evaluation of Irrigation Strategies in Watermelons - Juan Enciso
Moderator
TW

Timothy Waller

Rutgers, The State University of New Jersey
Timothy J Waller, Ph.D. is serving in his fourth year as the Commercial Nursery Agent of Rutgers Cooperative Extension in southern NJ, based out of Cumberland County. Tim has a Ph.D. in Plant Biology with a focus on fungal plant pathology and has been a licensed pesticide applicator... Read More →
Wednesday September 25, 2024 4:29pm - 5:10pm HST
Lehua Suite

4:30pm HST

CHEX/FP - Evaluation of Irrigation Strategies in Watermelons
Wednesday September 25, 2024 4:30pm - 4:40pm HST
The Lower Rio Grande Valley farmers traditionally irrigate vegetable crops with furrow irrigation systems. To conserve water and mitigate the effects of droughts, there is a need to adopt more efficient irrigation and fertilization methods and practices in vegetable crops to increase crop production quality and profitability. Farmers that use furrow irrigation systems apply from 4 to 6 inches per irrigation depending on their furrow length and apply more than five irrigations during the vegetable growing season, and using between 20 inches (1.7 ac-ft) and 40 inches (3.3 ac-ft) of irrigation water in their fields. Vegetables have a shallow root system, so farmers must irrigate frequently to maintain good moisture levels during the growing season for optimum growth, possibly wasting water. We use image analysis derived from Unmanned Aerial Systems (UAS) and irrigation soil water sensors to provide management recommendations to schedule drip and surface irrigation to conserve additional amounts of water. We established replicated research experiments using subsurface drip irrigation and soil water sensors (watermark sensors) to irrigate watermelons and other vegetable crops. We grew plants under three different water levels to trigger irrigation (50, 75, and 100 cb). A drip irrigation system with plastic mulch was placed in the field, as well as soil-water sensors, to measure and monitor the soil moisture. After calculating the water used in the three water level treatments, the 50 cb treatment used 0.27 ac-ft, the 75 cb treatment used 0.24 cb and 0.22 ac-ft was used by the 100 cb treatment. According to our results, we could conserve up to 3.0 ac-ft with our recommendations. We concluded that watermelons could be managed when the soil-water sensor readings range between 50 and 75 CB and approximately 0.3 ac-ft of water using subsurface drip irrigation. We obtained an average yield of 53,536 lb/ac, when irrigated under the 50 cb treatment, 42,059 lb/ac at 75 cb, and 36,719 lb/ac at 100 cb.
Speakers Co-authors
Wednesday September 25, 2024 4:30pm - 4:40pm HST
Lehua Suite

4:40pm HST

CHEX/FP - Advances in Phytophthora, Pythium, and Phytopythium Species Detection, Isolation, Culture, Diagnostics, and Virulence Rejuvenation
Wednesday September 25, 2024 4:40pm - 4:50pm HST
Not only are Phytophthora, Pythium, and interesting Phytopythium species potentially devastating horticultural pathogens, they regularly present challenges in vitro. In this study, multiple established and novel methodologies were built upon to bolster researchers’ ability to quickly isolate, differentiate, and promote virulence of multiple oomycetes principally collected from symptomatic conifers and nearby water sources. These methods allow greater flexibility in generating clean mycelial cultures for genetic characterization, varying pathogen structures for use in novel bioassays (such as synchronized production of sporangia or zoospores), and ultimately inoculations to evaluate oomycide efficacy or make headway towards completion of Koch’s postulates for previously uncharacterized host: pathogen pairings. Phytopythium vexans (Pp. vexans) (n=8 isolates), three Phytophthora species / species complexes including P. cinnamomi (n=10), P. cryptogea / drechsleri complex (n=4) and P. humicola (n=2), as well as 5 tentative species of Pythium, were evaluated. Isolations took two forms, standard root sampling onto Phytophthora selective media (PARPH), or water-based sampling through a modified ‘baiting/trapping’ technique that utilized on-site collected water samples in the laboratory. The ‘baits’ were Cannabis sativa seed, Vigna radiata beans, and Rhododendron maximum leaves suspended in aerated water samples or slurry of silt/soil. Samples were evaluated on V8-agar (V8A), pea agar (PA), pea broth (PB), potato dextrose agar (PDA), cornmeal agar (CMA), and water agar (WA), each of which provided distinct morphological indicators and structures useful in diagnostic guides and in bioassays or inoculations. As is typical with all plant pathogens, the longer they remain in culture, the less virulent they may become. With oomycetes, this is compounded as the pathogen will often go into chlamydospore or oospore formation (long lived survival structures) which are not ideal for experimentation. Inclusion of germinated then surface sterilized (70% ethanol for 30s) Vigna radiata and Lupinus perennis sprouts into recently poured (still liquid) 1/8 clarified V8 juice agar (1/8 clV8A) provided a media capable of rejuvenating the pathogen due to presence of living roots and dynamic plant nutrients. This allows for more predictability of zoospore formation, especially if they are intended to be used with a time sensitive trials. In numerous incidences multiple species of Phytophthora and Phytopythium vexans isolates went into zoospore release simultaneously by utilizing these approaches in combination with resource starvation and culture washing with sterile distilled water. Taken together these approaches will greatly aid any researcher working with root disease oomycetes in culture.
Speakers
WE

William Errickson

Rutgers University
Wednesday September 25, 2024 4:40pm - 4:50pm HST
Lehua Suite

4:50pm HST

CHEX/FP - Effect of Planting Date on Strawberry Yield
Wednesday September 25, 2024 4:50pm - 5:00pm HST
Optimizing planting date for strawberry in California production is a sustainable measure to maximize yield and maintain plant health. The goal of this project is to assess the optimal planting date for two predominant cultivars: 'Monterey' and 'Fronteras'. The trial was conducted in field 25 at Cal Poly, San Luis Obispo. The experimental area consisted of 3 beds, each 53.5 ft. long. Standard 64-inch beds with 4 rows of plants per bed and 3 lines of drip tape were used. Beds were planted at two-week intervals: 26 Oct, 9 Nov, 23 Nov 2022. Each bed was planted with four plots of ‘Monterey’ and four plots of ‘Fronteras’ (20 plants/plot). Plug plants were produced at North Carolina State University’s nursery and shipped overnight to Cal Poly and planted in the field the next day. First harvest was 13 Apr 2023 when the first fully red fruit were observed. Fruit were harvested, counted, and weighed twice weekly. The trial was completed 8 Aug 2023 and replicated in the 2024 growing season.
Speakers
SS

Samantha Simard

Cal Poly- San Luis Obispo
Wednesday September 25, 2024 4:50pm - 5:00pm HST
Lehua Suite

5:00pm HST

CH/FP - Outcomes of the Western Sustainable Agriculture Research and Education Summit in New Mexico
Wednesday September 25, 2024 5:00pm - 5:10pm HST
The aims of the federal initiative Sustainable Agriculture Research and Education (SARE) are multifaceted: 1) Foster responsible management of the nation's natural resources through the dissemination of location-specific, regional, and sustainable agricultural and ranching techniques, 2) Improve the livelihoods of farmers and ranchers, 3) Safeguard the well-being of individuals involved in food and agricultural systems by reducing reliance on harmful substances, 4) Encourage agricultural variety and resilience, and 5) Assess the local economic, social, and environmental impacts of adopting sustainable agricultural practices. To achieve these goals, SARE offers numerous grant opportunities for research projects, catering to farmers, ranchers, non-governmental organizations, and universities. SARE operates across four regions within the United States. New Mexico is in the Western region (WSARE) which is composed of individual state professional development programs in the area’s 13 states and 4 Pacific Island protectorates. In 2023, the NM WSARE Professional Development Program coordinated a Sustainable Agriculture Summit to better prioritize research and training needs in the state. The event was held in Santa Fe, NM, USA on 30 March, with a total of 58 participants in the full-day event. Among them were 32 agriculture professionals and 26 farmers and ranchers. The event consisted of two main sessions, a panel discussion, followed by an open forum. The panel was comprised of past Western SARE grant recipients and individuals who had submitted proposals, they provided overviews of their projects. Following the panel, summit participants engaged in a brainstorming session to identify critical sustainable agriculture project needs for producers in NM, focusing on research and training needs not previously emphasized in past funding. The priority areas identified by the participants were, in order of importance, 1) Irrigation/water use efficiency, 2) Farm economics, direct markets, and direct sales, 3) Non-traditional production, 4) Pest management, 5) Labor aids and technology adaptation, and 6) Generational transfer of farms and ranches. Each of these priorities was clearly outlined, and potential projects were identified accordingly. The outcomes of this summit were communicated to WSARE, the NM Department of Agriculture, and other funding agencies, offering valuable feedback to guide future proposals and funding initiatives in NM.
Speakers
ME

Mariela Estrada

New Mexico State University
Co-authors
IJ

Israel Joukhadar

New Mexico State University
Wednesday September 25, 2024 5:00pm - 5:10pm HST
Lehua Suite

6:00pm HST

Graduate Student Poster Competition
Wednesday September 25, 2024 6:00pm - 7:00pm HST
This competition is open to graduate students that have a poster presentation scheduled during the ASHS conference AND have also signed up to participate in this competition (Note: This is separate of the assigned time to present your abstract during the conference program).

Please note that if you do not also present your poster during the regularly scheduled Poster session, you will be disqualified from the Poster Competition.

Competition participants will be assigned to a room to present for the competition (this information will be emailed to you the week prior to the conference). You will be responsible for bringing your poster on a thumb drive to your assigned room in order to participate.

Wednesday September 25, 2024 6:00pm - 7:00pm HST
Lehua Suite
 
Thursday, September 26
 

7:59am HST

Ecological Physiology 2 (EcoPhys 2)
Thursday September 26, 2024 7:59am - 9:30am HST
Exploring the Effects of Irrigation Water Salinity on Physiology and Growth of Papaya (Carica papaya) in a Calcareous Soil - Ana Vargas
Physiological, Biochemical, and Morphological Responses of Achachairu (Garcinia humilis) to Soil Salinity, Flooding, and Exogenous Applications of 24-epibrassinolide - Federico Sanchez
Plant Physiological and Root Anatomical Responses of Two Novel Olive Cultivars (‘Oliana’ and ‘Lecciana’) Under Salinity - Khalid Hussain
Continuous monitoring of tree water status using microtensiometers for irrigation management in olive - Paula Guzman-Delgado
The Carbon Cost of Phosphorus Deficiency in Southern Highbush Blueberry - Marlon Retana-Cordero
Intra- and Inter-Annual Changes in Soil Health with Native Plant Monocultures - Bret Lang

Moderator
PG

Paula Guzman-Delgado

University of California Davis
Thursday September 26, 2024 7:59am - 9:30am HST
Lehua Suite

8:00am HST

EcoPhys 2 - Exploring the Effects of Irrigation Water Salinity on Physiology and Growth of Papaya (Carica papaya) in a Calcareous S
Thursday September 26, 2024 8:00am - 8:15am HST
In many tropical fruit production areas, including southern Florida, a rise in ocean levels resulting from climate change is anticipated to lead to greater inland intrusion of saltwater, thereby increasing salinity of the soil and/or irrigation water. Thus, knowing the salinity level of the soil or irrigation water that negatively impacts tropical fruit crops, including papaya, is important to alleviate salinity-induced damage to these crops. A study was conducted to evaluate physiological and growth responses of two papaya (Carica papaya L.) cultivars grown commercially in Florida (‘Red Lady’ and ‘Exp15’) to different irrigation salinity levels. Papaya seedlings were transplanted into 11.4-liter pots with Krome very gravelly loam soil; a calcareous soil collected from the papaya production area in south Florida. Each plant was manually irrigated three times per week with 1 liter of deionized water containing different concentrations artificial sea salt (Instant Ocean®) to obtain 4 salinity levels based on electrical conductivity (EC) of the irrigation water i.e., 0 (control), 3, 6, and 9 dS/m. Plants performance under different salinity levels was evaluated by determining net CO2 assimilation (A), stomatal conductance (gs), transpiration (E), the leaf chlorophyll index (LCI), and the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) on a weekly basis throughout the study. Normalized difference vegetation Index (NDVI) values derived from multispectral images were also collected weekly. After seven weeks, plants were harvested and leaf relative water content (RWC), leaf water potential, leaf area, and leaf, stem, and root dry weights were determined for all plants. Five weeks after treatments were initiated, for both cultivars, plants in the 6 and 9 dS/m treatments had lower A, E, gs, LCI, and Fv/Fm than plants in the other treatments. At the end of the experiment, plants in the 3, 6, and 9 dS/m treatments had significantly lower A, E, gs, LCI, Fv/Fm, leaf water potential, leaf area, and leaf, stem, and root dry weights than plants in the other treatments. Also at the end of the experiment, ‘Exp15’ plants in the 9 dS/m treatment had lower NDVI values than plants in the other treatments, whereas there was no difference in NDVI among treatments for ‘Red Lady’. There was no significant effect of salinity treatment on RWC. The findings suggest that 'Red Lady' and ‘Exp15’ papaya plants are unable to withstand salinity levels of 3 dS/m or higher in the calcareous agricultural soil of southern Florida.
Speakers
AV

Ana Vargas

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
BS

Bruce Schaffer

University of Florida
DH

Dong Hyeon Kim

University of Florida
NA
MS

Muhammad Shahid

University of Florida
NA
YG

Young Gu Her

University of Florida
NA
YL

Yuncong Li

University of Florida
NA
Thursday September 26, 2024 8:00am - 8:15am HST
Lehua Suite

8:15am HST

EcoPhys 2 - Physiological, Biochemical, and Morphological Responses of Achachairu (Garcinia humilis) to Soil Salinity, Flooding, and
Thursday September 26, 2024 8:15am - 8:30am HST
Achachairu (Garcinia humilis (Vahl) C.D. Adams) is a slow-growing tropical fruit tree indigenous to the Amazonian forests in Bolivia. Each tree can produce over 15,000 fruit (400 kg/tree) harvested from cultivated and wild trees. It has significant horticultural potential because the fruit is considered delicious by many people who have tasted it. Thus, its commercial cultivation has extended to Brazil, Mexico, and Australia. The responses and tolerance of this species to abiotic stresses and the use of chemical priming to mitigate stress have never been reported. The study investigated the physiological, biochemical, and morphological responses to flooding and salinity, and the priming with 24-epibrassinolide (EB) to increase flooding and salinity tolerance of G. humilis. Three-year-old achachairu seedlings were used in several sequential experiments, including applying flooding, salinity, and EB priming in different combinations and durations. Physiological variables including leaf gas exchange [net CO2 assimilation (A), stomatal conductance of H2O (gs), and intercellular CO2 concentration (Ci)], leaf chlorophyll index (LCI), and the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) were measured. Leaf and root nutrient concentrations, antioxidant responses, reactive oxygen species (ROS), and lipid peroxidation (MDA) were also measured. Results showed that G. humilis is very tolerant of prolonged flooding of up to 30 d, medium levels of salinity of up to 6 dSm-1, and the combined effect of flooding and salinity. Tolerance to these stresses was exhibited by physiological, biochemical, and morphological responses, consistent with tolerance traits, such as maintaining basal levels of photosynthesis, ion homeostasis, and nutrient balances, robust antioxidant responses to counter ROS increases, and limited lipid peroxidation, all of which may help limit physiological damage. Application of 1.0 mg L-1 EB as a foliar and root-drench before flooding or salinity treatments increased the levels of tolerance of G. humilis to salinity and flooding, most likely by reinforcing antioxidant responses which helped decrease ROS and lipid peroxidation.
Speakers
avatar for Federico Sanchez

Federico Sanchez

University of Florida
Co-authors
AS

Ali Sarkhosh

University of Florida
NA
BS

Bruce Schaffer

University of Florida
HB

Haimanote Bayabil

University of Florida
NA
JH

Jonathan H Crane

University of Florida
MA

Muhammad Adnan Shahid

University of Florida
NA
Thursday September 26, 2024 8:15am - 8:30am HST
Lehua Suite

8:30am HST

EcoPhys 2 - Plant Physiological and Root Anatomical Responses of Two Novel Olive Cultivars (‘Oliana’ and ‘Lecciana’) Under Salinity
Thursday September 26, 2024 8:30am - 8:45am HST
Soil salinity poses a significant challenge in agriculture, disrupting the normal functioning of plants by reducing water and nutrient uptake. Olive trees (Olea europaea), common in Mediterranean regions, exhibit moderate to high tolerance to salinity, varying by cultivar. Interest in cultivating olive trees is growing in Florida’s coastal areas, characterized by poorly drained soil and low-quality groundwater, leading to salt accumulation in the root zone. The high salinity levels in these areas present a significant challenge for crop cultivation. Therefore, introducing new salt-tolerant cultivars is necessary to mitigate salinity stress. This study aimed to evaluate the plant physiological and root anatomical responses of two novel olive cultivars - ‘Oliana’ and ‘Lecciana’ - to salinity stress, assessing their salt tolerance. Eight-month-old plants were grown in pots using a sand medium under greenhouse conditions and treated with varying salt concentrations (0 mM, 50 mM, and 100 mM). The experiment followed a completely randomized design with three replications, each consisting of nine plants. Plants were irrigated at weekly intervals with half-strength Hoagland solution to meet their nutrient requirements. Height and trunk diameter were measured at four different time points (0, 15, 30, and 45 days). At the end of the trial, plants were destructively sampled for biomass, nutrient content, and root anatomical measurements at the latter three time points. Significant differences were observed in height, trunk diameter, and nutrient contents between the control and NaCl treatments. These findings serve as a baseline for the commercial development of salt-tolerant olive cultivars.
Speakers
KH

Khalid Hussain

University of Florida
NA
Co-authors
JF

John-Paul Fox

University of Florida
LR

Lorenzo Rossi

University of Florida
Thursday September 26, 2024 8:30am - 8:45am HST
Lehua Suite

8:45am HST

EcoPhys 2 - Continuous monitoring of tree water status using microtensiometers for irrigation management in olive
Thursday September 26, 2024 8:45am - 9:00am HST
Water scarcity is challenging agricultural production, demanding more precise and efficient irrigation management. Plant-based continuous monitoring has emerged as a promising approach for detecting water stress progression and optimizing irrigation. However, its practical implementation is hindered by the complex interpretation of the sensors’ outputs and plant physiological status relationships. Plant water potential is among the most robust water status indicators and is widely used for irrigation management. Nevertheless, its measurement is time-consuming and requires skilled personnel, making it difficult to have frequent assessments. In this study, we explored the potential of using continuous water potential sensing to quantify olive water status and its response to irrigation. Specifically, we compared continuous and discrete tree-level measurements of water status using microtensiometers and the pressure chamber, respectively. The microtensiometers proved effective in capturing tree water status dynamics, enabling a prompt assessment of the impact of irrigation practices. Preliminary analyses show a good linear correlation between midday trunk and stem water potential values obtained with microtensiometers and the pressure chamber, with the former being less than 0.5 MPa lower, a difference that could be attributed to the specific measurement of each technique. Importantly, having continuous data allows the extrapolation of several water status parameters which can provide key information in addition to the single timepoint midday values. Overall, this study suggests microtensiometers can be a useful tool to optimize water application in olive orchards.
Speakers
PG

Paula Guzman-Delgado

University of California Davis
Co-authors
AP

Amrit Pokhrel

University of California Davis
NA
ES

Emily Santos

University of California, Davis
NA
KS

Kosana Suvočarev

University of California Davis
NA
Thursday September 26, 2024 8:45am - 9:00am HST
Lehua Suite

9:00am HST

EcoPhys 2 - The Carbon Cost of Phosphorus Deficiency in Southern Highbush Blueberry
Thursday September 26, 2024 9:00am - 9:15am HST
Phosphorus (P) deficiency in plants causes detrimental effects on their growth and development, as P is a key macronutrient used in various physiological, biochemical and cell signaling processes. Research has shown that P-deficient plants exhibit several symptoms such as changes in leaf coloration, root morphology, and plant growth. However, many of those studies ignore gas exchange parameters. In this research, we studied the connection between P-deficiency and carbon (C) gain and loss in southern highbush blueberry (SHB, Vaccinium corymbosum interspecific hybrids) young plants to estimate the C cost of P-deficiency. The experiment was conducted using a hydroponic system where three-month old plants of ‘Farthing’ and ‘Keecrisp’ varieties grew in individual 2-L reservoirs filled with continuously-aerated complete nutrient solution containing 15 mg/L P during a 35-day acclimation period. After the acclimation period, plants were separated into two groups and continued to grow for 56 more days (treatment period). One group ( P) was grown in the complete nutrient solution, while the second group (-P) was grown in a P-free nutrient solution (0 mg/L P). We designed and tested a whole-plant gas exchange system that utilizes two infrared gas analyzers (CIRAS-3 and CIRAS-4) to simultaneously measure root system respiration and whole-plant C assimilation. Additionally, we measured root C exudation, fresh and dry mass accumulation, and P concentration and content. We induced P-deficiency as -P plants of both varieties had mature and young leaf P concentration below 0.12% (reference deficiency level). P plants had higher P concentration after treatment period. -P ‘Farthing’ plants had 89% less daily C assimilation than P plants, while no differences were observed in ‘Keecrisp’. Daily root respiration and C exudation, considered as ways of C loss, were, 3.5 and 2.9 times higher in -P than in P plants of ‘Farthing’. Similarly, -P ‘Keecrisp’ plants had 3.8 and 2.5 times more daily root respiration and C exudation compared to those under P. Ultimately, P deficiency caused a 136% reduction in daily C gain of ‘Farthing’ plants, while there were no differences between treatments in ‘Keecrisp’ plants. Our findings suggest that responses to P deficiency in SHB are genotype-specific, and that C budget and distribution in the plant play an important role in the responses to P-deficiency.
Speakers
MR

Marlon Retana-Cordero

University of Florida
Co-authors
GN

Gerardo Nunez

University of Florida
Thursday September 26, 2024 9:00am - 9:15am HST
Lehua Suite

9:15am HST

EcoPhys 2 - Intra- and Inter-Annual Changes in Soil Health with Native Plant Monocultures
Thursday September 26, 2024 9:15am - 9:30am HST
The interactions between plants and their soil environment influence overall soil system health. Soil provides plants with the structural support, water, nutrients, and microbial interactions they need for creating biomass and for reproduction. Conventional agriculture practices degrade soil; however, small plots of native plants within agricultural settings have been shown to provide disproportionally large benefits to both ecological and agricultural landscapes. In other words, even small plots of native plants can improve soil health. Although small plots of mixed native plant species improve soil health, they offer little in the way of income opportunities for producers through seed collection and sales. However, plots of native monocultures may offer producers an opportunity to harvest and sell seeds, taking advantage of the increasing demands of the native seed market while also increasing soil health. Therefore, this study's objective is to quantify the effects of small native plant monocultures on soil health and compare them to soil health from conventional crop plots. We investigated biological indicators of soil health such as organic matter, organic carbon, and microbial communities as well as abiotic indicators like nutrient composition. We hypothesize that, compared to crop plots, native monoculture plots will have more microbial diversity and higher amounts of soil nutrients. We tested our hypothesis by comparing soil health characteristics from plots containing five established native monocultures: Dalea candida, Agastache nepetoides, Glycyrrhiza lepidota, Liatris ligulistylis, and Tradescantia occidentalis; and one crop plot planted with a corn and soybean rotation. During the second and third season of growth, monthly soil samples were taken, and soil indicator values were compared using Tukey’s HSD post hoc tests after performing an analysis of variance (ANOVA). Results suggest that native plant species influenced soil health differently than crop rotations after three seasons of growth. Compared to crop plots, soil samples from two species of native plants, Agastache nepetoides and Tradescantia occidentalis, had higher fungi-to-bacteria ratios (p = 0.0160 and p < 0.0001, respectively), and higher amounts of saprophyte biomass (p = 0.0040 and p = 0.0484, respectively). Soils from the Agastache nepetoides plots also had higher amounts of Pre18 cyclo fatty acids (p = 0.0022) and potassium (p = 0.0159). These two species of native plants show potential for improving soil health after three years of establishment. Adding these two native monocultures to marginal production land may add soil health benefits during early establishment periods while providing a marketable crop for producers.
Speakers
BL

Bret Lang

Student, South Dakota State University
Co-authors
LP

Lora Perkins

South Dakota State University
NA
Thursday September 26, 2024 9:15am - 9:30am HST
Lehua Suite

9:59am HST

Weed Control and Pest Management 3 (WCPM 3)
Thursday September 26, 2024 9:59am - 11:30am HST
A Water Soluble β-triketone Enriched Extract of Manuka Oil has Increased Efficacy Compared to Vinegar and D-Limonene in a Field and Greenhouse Evaluation - Casey Barickman
Weed Control in Bell Pepper after Herbicide Application in a Reduced Sunnhemp Cover Crop Population. - Peter Dittmar
Assessing the Effects of Container Sizes and Weed Densities on Weed-ornament Competition in Nursery Container Production - Debalina Saha
Herbicide-Resistant Italian Ryegrass in Oregon Hazelnut Orchards: Evaluating Nonchemical and Chemical Methods - Marcelo Moretti
Limiting Liverwort Growth by Allelopathic Effects of Organic Mulches in Ornamental Production - Manjot Sidhu
Effect of Application History on Preemergence Herbicide Persistence - Travis Gannon

Moderator
PD

Peter Dittmar

University of Florida
Thursday September 26, 2024 9:59am - 11:30am HST
Lehua Suite

10:00am HST

WCPM 3 - A Water Soluble β-triketone Enriched Extract of Manuka Oil has Increased Efficacy Compared to Vinegar and D-Limonene in a Field and Greenhouse Evaluation
Thursday September 26, 2024 10:00am - 10:15am HST
Weed management strategies for specialty and organic crop production are challenging due to limited chemical weed control products with good efficacy that are cost effective. The need for new bioherbicide modes of action has become increasingly urgent in modern agriculture as most bioherbicides have nonspecific modes of action with no systemic activity. Introducing new modes of action is essential to diversify weed control strategies, minimize the risk of resistance development, and ensure sustainable weed management practices. By fostering innovation in bioherbicide development and promoting the use of novel modes of action, we can safeguard our agricultural systems, reduce the environmental impact of weed management, and maintain the ability to feed a growing global population while preserving the long-term health of our ecosystems. Manuka oil is derived from the leaves and branches of the Manuka tree (Leptospermum scoparium) and contains β-triketones. The β-triketone rich fraction contains leptospermone and inhibits a key enzyme, p-hydroxyphenylpyruvate dioxygenase (HPPD). This process directly inhibits carotenoid biosynthesis, upstream in the biochemical pathway, which causes damage to the photosynthetic apparatus and leads to bleaching of the leaf tissue which eventually kills the plant. The β-triketone extract at 2% and 4% had up to 97% control against different weed species in field and greenhouse evaluations. The β-triketone extract was significantly more efficacious verse other bioherbicides such as the 20% vinegar and 12.5% D-limonene. Additionally, the β-triketone extract was just as effective as the 2% glyphosate treatment in the greenhouse evaluation against Amaranthus palmeri and Digitaria sanguinalis. The β-triketone extract also reduced Cyperus esculentus growth by 70% at 9 days after treatment. Thus, there is significant evidence that commercializing a water soluble β-triketones enriched extract of Manuka oil can be an effective weed control strategy in crop production systems, especially in specialty and organic cropping systems where the need of bioherbicides is critically imperative.
Speakers Co-authors
AR

Amber Reichley

USDA-ARS
NA
CL

Charles L. Cantrell

USDA-ARS-NPURU
NA
Thursday September 26, 2024 10:00am - 10:15am HST
Lehua Suite

10:15am HST

WCPM 3 - Weed Control in Bell Pepper after Herbicide Application in a Reduced Sunnhemp Cover Crop Population.
Thursday September 26, 2024 10:15am - 10:30am HST
Sunnhemp cover crop seed germination can be lowered due to poor seed quality, incorrect planting depth, or adverse weather effects. The objective of this research is to evaluate weed control by herbicides in a reduced sunnhemp population. Research trials were conducted at the Plant Science Research and Education Unit, Citra, Florida, and the Syngenta Vero Beach Research Center, Vero Beach, FL. The treatments were sunnhemp at 44.83 kg/ha, sunnhemp at 22.4 kg/ha ( no herbicide, bentazon at 1.12 kg/ha, sulfentrazone at 0.14 kg/ha, halosulfuron at 0.04 kg/ha, glyphosate at 5.5 kg/ha followed by glyphosate at 5.5 kg/ha, and oxyfluorfen at 0.56 kg/ha), and a nontreated weed fallow. Sunnhemp was planted in Citra on July 18, 2023 and in Vero Beach on July 27, 2023; herbicides were applied 2 weeks after planting when the sunnhemp were 15 to 25 cm tall. After 8 weeks of growth, the sunnhemp was mowed and the field was prepared for laying plastic and planting bell pepper. The oxyfluorfen caused significant injury to the sunnhemp; this treatment had similar broadleaf, grass, and nutsedge populations to the weed fallow. In Citra at 14 and 28 days after application, bentazon, sulfentrazone, or halosuluron had lower populations than sunnhemp at 22.4 kg/ha alone, but at cover crop termination all the cover crop treatments had similar nutsedge control. All cover crop alone and cover crop herbicide treatments had similar grass and broadleaf control at crop termination. In the bell pepper crop at Vero Beach, oxyfluorfen had greater nutsedge populations than all the other treatments. Crop yields were similar among the cover crop alone or with a herbicide. The application of a herbicide in a reduced cover crop population is not necessary for increased weed control in a fall cash crop. However, the reduced cover crop population in this study was artificially created so the sunnhemp population was equal spaced through the entire plot. If the sunnhemp is significantly impacted like the oxyfluorfen treatment, then more intense recovery action may be necessary.
Speakers
PD

Peter Dittmar

University of Florida
Co-authors
DD

Devin Davis

University of Florida
NA
Thursday September 26, 2024 10:15am - 10:30am HST
Lehua Suite

10:30am HST

WCPM 3 - Assessing the Effects of Container Sizes and Weed Densities on Weed-ornament Competition in Nursery Container Production
Thursday September 26, 2024 10:30am - 10:45am HST
Effective weed management strategies are essential for producing high-quality and successful ornamentals in nurseries and greenhouses. Weeds can affect both the productivity and quality of ornamentals, especially in containers where nutrient and moisture availability are limited, due to restricted space. The objective of this study was to determine how different types of weed species at various densities and in different container sizes affect the growth of ornamental plants. Two rounds of greenhouse experiments were conducted at the Horticulture Teaching and Research Center, Michigan State University, in summer and fall 2023. Seeds of large crabgrass {Digitaria sanguinalis (L.) Scop} and smooth pigweed (Amaranthus hybridus L.) were grown separately until they attained the 4-6 leaf stage. Liners of hydrangea {Hydrangea macrophylla (Thunb.) Ser.} and syringa (Syringa vulgaris L.) were planted in containers of three different sizes 0.67 gallons (2.54 liters), 1.5 gallons (5.67 liters), and 3 gallons (11.35 liters) containing standard bark-based substrate amended with controlled-release fertilizer. All plants received 0.5 inches (1.3 cm) of water thrice daily and were allowed to grow till they were well established. Then the weed seedlings of large crabgrass and smooth pigweed were carefully transplanted to each container-grown ornamental plant at different densities of 0,1,3,6 per pot, with the density of 0 being the control set. After weed transplantation, all pots were maintained inside the greenhouse for 8 weeks. The experimental design utilized a randomized complete block design with six replications per treatment. Initial and final growth indices of ornamentals were recorded. At 8 Weeks After Potting (WAP) fresh weights of both the weed species and the ornamentals were recorded separately. All data were analyzed in SAS by ANOVA and the Tukey’s HSD test were performed to separate out the means. Results showed that final growth indices of hydrangea were significantly higher than syringa and maximum in 3-gallon containers. Overall, large crabgrass at density of 6 was more competitive than smooth pigweed and hydrangea performed better than syringa in 3-gallon container size in competing the weed species.
Speakers
DS

Debalina Saha

Michigan State University
Co-authors
GA

Greeshmanth Alluri

Michigan State University
Thursday September 26, 2024 10:30am - 10:45am HST
Lehua Suite

10:45am HST

WCPM 3 - Herbicide-Resistant Italian Ryegrass in Oregon Hazelnut Orchards: Evaluating Nonchemical and Chemical Methods
Thursday September 26, 2024 10:45am - 11:00am HST
Herbicide-resistant Italian ryegrass (Lolium multiflorum Lam.) presents a significant challenge in hazelnut orchards across Oregon, with confirmed resistance to multiple herbicide modes of action groups (1, 2, 9, 10, 15, and 22). Four field studies were conducted in 2023 to evaluate nonchemical and chemical methods for controlling Italian ryegrass during spring. Tested treatments included mowing at 2 km h-1, electric weeding control (EWC) at 15 MJ ha-1 (2 km h-1), and glufosinate application at 1.68 kg ai ha-1, administered once or twice. Furthermore, combinations of EWC with mowing or glufosinate were examined, resulting in eleven treatments. EWC was performed using alternating current and 30 kW (EH-30 Thor, ZassoTM), treating swaths 1.2 m wide. Assessments conducted 56 days after initial treatment (DAIT) revealed that single mowing showed no significant difference compared to untreated plots. However, when mowing was performed twice, it led to a 30% reduction in inflorescence density and an 84% reduction in weight. EWC, applied once or twice, resulted in significant decreases in Italian ryegrass inflorescence density (51-58%), weight (55-73%), and shoot weight (45-75%) compared to untreated plots, with no significant differences observed between single or double applications. Similarly, glufosinate applied once or twice substantially reduced Italian ryegrass inflorescence density (68 to 86%) and weight (73 to 93%). Combinations of EWC with mowing or glufosinate demonstrated high efficacy, achieving control rates of 89 to 96% and exhibiting comparable efficacy to two applications of glufosinate (96%). These findings suggest that EWC, when applied during the spring period, can effectively control Italian ryegrass, offering comparable efficacy to glufosinate and superior efficacy to mowing.
Speakers
MM

Marcelo Moretti

Oregon State University
Thursday September 26, 2024 10:45am - 11:00am HST
Lehua Suite

11:00am HST

WCPM 3 - Limiting Liverwort Growth by Allelopathic Effects of Organic Mulches in Ornamental Production
Thursday September 26, 2024 11:00am - 11:15am HST
Liverwort (Marchantia polymorpha) is one of the problematic weeds in ornamental crop production that deteriorates the quality and aesthetic value of ornamentals. To study the effectiveness of allelopathic properties of organic mulch extracts, six different organic mulch materials including rice hull (RH), cocoa hull (CH), pine bark (PB), maple leaf (ML), shredded cypress (SC) and red hardwood (HW) were used for obtaining mulch extracts. The extracts were prepared by following the modified EPA 1312 synthetic precipitation procedure. In the lab experiment, the mulch extracts obtained were used to impregnate agar media at an increasing dose at either 1x (2ml), 2x (4ml), 3x (6ml), and 4x (8ml) rates. Ten gemmae were transferred to the culture medium in each petri dish and all petri dishes containing gemmae were maintained inside the growth chamber. Data was recorded for number of gemmae germinating in each petri dish and at the end of experiment, the length and width of the thallus derived from each gemmae were measured. For greenhouse experiment, the mulch extracts were applied to nursery containers filled with standard substrate and amended with controlled-release fertilizer for assessing the postemergent liverwort control in nursery containers. Either RH, HW, CH, ML, SC or PB mulch extracts were applied to each of the container uniformly at either 1X (15ml), 2X (30ml), 3X (45ml), and 4X (60ml) rates, at the beginning of experiment and bi-weekly until 10 weeks. Control set without any mulch extract was included as well. Percent of substrate surface covered by liverwort thalli was visually estimated bi-weekly until 10 weeks after first treatment. Fresh biomass of the thalli and number of gemmae cups in each pot were also recorded at the end of the experiment. Both lab and greenhouse experiments had four replications per treatment and were arranged in a randomized complete block design. After 1 week in the growth chamber, ML followed by SC, PB and RH extracts showed maximum suppression of liverwort gemmae germination. At 2 weeks, all rates of ML provided complete inhibition of liverwort. In the greenhouse, all the mulch extracts were able to provide complete liverwort control for the first two weeks. PB and HW mulches showed excellent liverwort control and minimum biomass of liverwort after 10 weeks as compared to other mulches. Hence, the allelopathic potential of the organic mulches can be a promising option for biopesticidal control of liverwort, and a component of integrated liverwort management.
Speakers
MS

Manjot Sidhu

Michigan State University
Co-authors
DS

Debalina Saha

Michigan State University
Thursday September 26, 2024 11:00am - 11:15am HST
Lehua Suite

11:15am HST

WCPM 3 - Effect of Application History on Preemergence Herbicide Persistence
Thursday September 26, 2024 11:15am - 11:30am HST
Preemergent herbicides are commonly applied to control many annual weed species in turfgrass systems. Oxadiazon and prodiamine are pre-emergent herbicides that effectively inhibit the growth of emerging annual grasses and broadleaf weeds without harming certain turfgrass species. However, in recent years, a decline in the efficacy of oxadiazon and prodiamine has been observed by golf course managers, leading to an increase in application rates in an attempt to mitigate the issue. Therefore, the objective of this study was to characterize degradation processes that affect oxadiazon and prodiamine persistence and efficacy in order to identify solutions or mitigation strategies. Soil samples were collected from unique sites throughout North Carolina. Field studies were organized as a randomized complete block design containing 3 replications and 2 experimental runs. Treatments were arranged in a split-split plot design, where the whole plots consisted of 4 sites with histories of continuous oxadiazon or prodiamine use (never applied, applied 1-2 years, ~7 years, > 15 years), the sub-plots were 2 treatments (non-sterilized and sterilized), and the sub-sub-plots were 6 collection timings (14, 28, 42, 56, 112, and 168 days after treatment). Herbicide residue quantifications were determined using high-performance liquid chromatography. Data were recorded and converted into a percentage of the applied rate. A higher percent of oxadiazon was observed for sterilized soil (79.2%) compared to non-sterilized soil (73.7%). In the non-sterilized soil, at 14 DAT there were no differences between periods of use. However, at 28 DAT, the soil with no use history presented a higher percentage of oxadiazon (83.0%) compared to 1 and 15 years (75.5%, and 77.1% respectively). Furthermore, at 42 and 56 DAT, the soil with no history of application exhibited the highest percentage of oxadiazon among all periods of use. Findings of this study suggest that there is higher concentration of oxadiazon, meaning less degradation, in the soils with no history of application.
Speakers
TG

Travis Gannon

NC State University
Co-authors
AV

Alex Veverka

NC State University
NA
EG

Estefania Gomiero Polli

NC State University
NA
KA

Khalied Ahmed

NC State University
NA
RR

Ronald Rogers

NC State University
NA
Thursday September 26, 2024 11:15am - 11:30am HST
Lehua Suite

11:59am HST

Temperate Tree Nut Crops 2 (NUTS 2)
Thursday September 26, 2024 11:59am - 1:30pm HST
A Look at Heat Stress on Micro-propagated Pecan Trees - Doris Alexa Arnedo
Unraveling the role of LEA(Late embryogenesis abundant) genes in pecan stress resilience - Sahithi Pulicherla
Discovery of Early Biomarkers for the Scab Resistance of Pecan Seedlings Using Metabolomic Analysis Combined with Machine Learning Algorithms - Min Jeong Kang
Developmental Transcriptomics of Pecan Fruit in ‘Mahan’ and ‘Tiny Tim’ - June Labbancz
Pistachio Orchard Productivity Enhancement Through Molecular Marker Preselection - Ewelina Jacygrad
Fatal Flaws of Experimental Almond Varieties and Selections - Luke Milliron
Advancing Cocoa Yield Forecasting in Ecuador Using Machine Learning and Field Data Integration - Daniel Mancero
Maturity stage at harvest modulates fruit softening and quality of jackfruit - Zora Singh
Growing papaya in Mississippi - Guihong Bi


Moderator
avatar for Doris Alexa Arnedo

Doris Alexa Arnedo

New Mexico State University
Thursday September 26, 2024 11:59am - 1:30pm HST
Lehua Suite

12:00pm HST

NUTS 2 - A Look at Heat Stress on Micro-propagated Pecan Trees
Thursday September 26, 2024 12:00pm - 12:15pm HST
Carya illinoinensis (pecan) belongs to the Juglandaceae family, and the native region extends from Illinois, USA to Oaxaca, Mexico. Pecan is a valuable economic crop due to its nutritious and tasty nuts, and the United States produced 275 million pounds of pecans in 2022. As temperatures are increasing it is important to understand the impact on pecan trees. By 2100, the average U.S. temperature is projected to increase by about 3°F to 12°F. Plants deal with heat stress in several different ways including the production of heat shock proteins (HSPs) and their transcription factors known as heat shock factors (HSFs). HSFs initiate the transcription of genes that encode heat shock proteins (HSPs), that deal with heat stress by initiating protein folding and aid in the repair or removal of damaged proteins. In this study, we aim to look at the genetic networks that are impacted when multiple genotypes are subjected to high-heat environments. For this study, seedstocks from multiple genotypes that span the geographic region of North America were introduced into micropropagation. These include seedstocks from ‘Elliott’, ‘Apache’, ‘Cape Fear’, ‘Mahan’, ‘Giles’, ‘Sioux’, ‘Wichita’, ‘Western’, and native seedstocks of unknown genetics from Ohio. A preliminary heat stress assay was performed on a micropropagated ‘Elliott’ line by subjecting three small trees to 43°C for two hours prior to flash freezing in liquid nitrogen and comparing these to the same clonal line (three trees) that remained at 23°C. Real time quantitative reverse transcription PCR (QRT-PCR) was performed on the heat stress and control trees. Normalized gene expression indicated that CiHSP1 expression was 2X higher in the heat-treated pecan trees than CiHSP1 expression of the control trees. The additional micropropagated seedstocks listed above are being subjected to heat stress at different temperature ranges and time intervals. The replicated assays will be analyzed using RNA-Seq and qRT-PCR to determine differential gene expression of control and heat-treated trees especially between the HSPs and HSFs. These assays will help determine the gene networks that pecan trees use as they experience heat stress and will help determine how different pecan genetics that originate in different geographic regions react to heat stress.
Speakers
avatar for Doris Alexa Arnedo

Doris Alexa Arnedo

New Mexico State University
Co-authors
AH

Angelyn Hilton

USDA ARS Southern Plains Agricultural Research Center
NA
JR

Jennifer Randall

New Mexico State University
NA
KC

Kimberly Cervantes

New Mexico State University
NA
SP

Sahithi Pulicherla

New Mexico State University
Thursday September 26, 2024 12:00pm - 12:15pm HST
Lehua Suite

12:15pm HST

NUTS 2 - Unraveling the role of LEA(Late embryogenesis abundant) genes in pecan stress resilience
Thursday September 26, 2024 12:15pm - 12:30pm HST
Late embryogenesis abundant (LEA) proteins, encoded by a family of LEA genes, are vital in conferring stress tolerance in plants through their unique intrinsically disordered structure that can stabilise cellular components under desiccated conditions. While the protective capabilities of LEA proteins are well-documented across various crops, their specific roles in pecan (Carya illinoinensis), a highly nutritious and economically significant nut crop, remain largely unexplored. This gap of knowledge needs to be addressed as pecan yields face threats from escalating drought and salinity issues, intensified by ongoing climate change. This study represents the first comprehensive analysis of LEA genes within the pecan genome. We have successfully identified 332 LEA genes distributed across 15 of the 16 chromosomes in four genomes of pecan, categorized into 8 distinct subgroups based on their conserved motif regions. Synteny analysis provided a deeper understanding of their evolutionary trajectories. Utilizing extensive transcriptomic datasets, we explored the tissue-specific expression patterns of LEA genes in pecan, discovering diverse expression profiles across various tissues. Ongoing studies include promoter analysis and assessments of gene expression under abiotic stress conditions. To specifically address the impact of drought, heat and salinity, clonal pecan plants are being subjected to these stressors under controlled conditions in tissue culture and greenhouse settings. This approach aims to directly observe the physiological and molecular responses of LEA genes under realistic stress simulations. The presence of LEA genes across a vast majority of pecan chromosomes and their diverse subgroup classifications suggests a genome-wide defense mechanism potentially key to enhancing the stress tolerance of pecan trees. By understanding and harnessing these genes, our research seeks to elucidate plant stress responses at the molecular level allowing the development of genetic strategies to ensure the sustainability of pecan by mitigating adverse environmental impacts on its production. This knowledge could also be applied in a diverse array of other economically significant crops.
Speakers
SP

Sahithi Pulicherla

New Mexico State University
Co-authors
AA

Alexa Arnedo

New Mexico State University
CM

Chris Mattison

United States Department of Agriculture
NA
JR

Jennifer Randall

New Mexico State University
NA
Thursday September 26, 2024 12:15pm - 12:30pm HST
Lehua Suite

12:30pm HST

NUTS 2 - Discovery of Early Biomarkers for the Scab Resistance of Pecan Seedlings Using Metabolomic Analysis Combined with Machin
Thursday September 26, 2024 12:30pm - 12:45pm HST
Pecans (Carya illinoinensis (Wangenh.) K. Koch) are globally consumed nuts and an important agricultural commodity in the United States. Scab is a devastating pecan disease, which necessitates the application of numerous fungicide sprays in the growing season of pecans. Even with the control measures, in wet years, scab infection results in great yield loss (over 50% loss in susceptible varieties) and deterioration of nut quality. Although there have been various efforts to alleviate the scab, the development of scab-resistant pecan cultivars is the most effective method to control the disease. However, current methods to assess pecan scab resistance require multiple years of field screening and complicated laboratory (microscopic) techniques. Thus, a simple and reliable method that can rapidly evaluate pecan scab resistance at an early stage of infection is necessary. In this study, metabolomic analysis with machine learning algorithms was utilized to identify early biomarkers for the scab resistance of pecan seedlings. Two pecan seedlings with contrasting scab resistance ('Pawnee' and 'Desirable') were inoculated with water (control), Pa-OK-11 (isolated from 'Pawnee'), and De-Tif-11 (isolated from 'Desirable') for 7 days. 'Desirable' seedlings exhibited resistance to Pa-OK-11, while 'Pawnee' seedlings showed moderate resistance to De-Tif-11. Both cultivars were susceptible to their respective isolates. Leave samples from each seedling were collected at different time points (0, 1, 2, 3, 4, 5, 7 days). For the metabolomics work, liquid chromatography‒mass spectrometry (LC‒MS) was employed to analyze metabolites in samples, which can cover a wide range of primary and secondary metabolisms, including carbon fixation, glycolysis, citric acid cycle, amino acid metabolism, phenylpropanoid, monolignol, and flavonoid biosynthesis. Different machine learning algorithms were compared to find differentially regulated metabolites (biomarkers) between scab-resistant and -susceptible seedling groups. With a combination of machine learning models, we obtained reliable potential biomarkers, e.g., phenolic acids, flavonoids, plant hormones, and their intermediates and precursors, involved in the early stage of scab infection. The selected markers are expected to be used to classify scab resistance levels in pecan seedlings within a week after infection, which may replace the conventional method (phenotype-based mass selection) for pecan breeding selection. In short, this research breaks the bottleneck of resistance screening in pecans and will help facilitate the early selection of scab-resistant pecan cultivars to achieve breeding goals.
Speakers
MJ

Min Jeong Kang

University of Georgia
Co-authors
JS

Joonhyuk Suh

University of Georgia
NA
LW

Lenny Wells

University of Georgia
NA
PC

Patrick Conner

University of Georgia
RP

Ronald Pegg

University of Georgia
NA
Thursday September 26, 2024 12:30pm - 12:45pm HST
Lehua Suite

12:45pm HST

NUTS 2 - Developmental Transcriptomics of Pecan Fruit in ‘Mahan’ and ‘Tiny Tim’
Thursday September 26, 2024 12:45pm - 1:00pm HST
Pecan (Carya illinoinensis) is a nut crop native to the United States and Mexico which is becoming an increasingly important crop globally. Juglandaceous nuts are uniquely high in antioxidants among nuts and a conversion equivalent derived from studies in mice indicates that consumption of 22-38 pecans per day may reverse metabolic disorder in an individual weighing 132 pounds, implying a role in a healthy diet. Despite this importance, relatively little is known about the molecular basis of pecan nut ontogeny compared to other nut crops, leading to difficulties in understanding the physiological issues which plague growers. Susceptibility to various biotic and abiotic disorders including pecan scab, vivipary, water split, and shuck decline are dependent upon the stage of development the pecan nut is in. To better understand the molecular basis and timing of pecan nut development, developmental time-course RNA-Seq was carried out on nuts collected from cultivars ‘Mahan’ (a large nut bearing pecan from Mississippi) and ‘Tiny Tim’ (a small nut bearing native pecan from Missouri) approximately biweekly through the growing season of 2022. Using this data, genes were grouped together into distinct developmental phases, connecting transcriptional changes to the already well-characterized ontogenic stages of pecan nut development.
Speakers Co-authors
WC

Warren Chatwin

USDA ARS Southern Plains Agricultural Research Center
NA
Thursday September 26, 2024 12:45pm - 1:00pm HST
Lehua Suite

1:00pm HST

NUTS 2 - Pistachio Orchard Productivity Enhancement Through Molecular Marker Preselection
Thursday September 26, 2024 1:00pm - 1:15pm HST
There is significant variation in tree size, which determines productivity, in commercial pistachio orchards planted with UCB-1 seedling rootstocks. It has been unclear to extent to which this is due to genetic differences or environmental variation. Nurseries have tried to tackle this problem by rogueing young seedlings before they are planted in orchards. However, our data previously demonstrated that performance in the first year is a poor predictor of later tree size. Genotyping by sequencing data from experimental and commercial orchards and genome wide association studies (GWAS), combined with our chromosome-scale, high quality, genome assemblies for the parental Pistacia atlantica and P. integerrima trees resulted in two highly informative molecular markers for vigor. Based on the genomic sequence information, we developed an inexpensive, quick, and easy qPCR protocol for single nucleotide polymorphism (SNP) marker analysis. We were able to predict the improved size distribution that extant orchards would have had if this marker had been used to rogue seedlings prior to planting in the orchards. We want this marker to make it available for nurseries to rogue out trees which would exhibit low vigor and productivity later in an orchard.
Speakers
EJ

Ewelina Jacygrad

University of California Davis
Co-authors
DG

Deborah Golino

University of California Davis
NA
JE

John E. Preece

University of California, Davis
NA
KC

Keri Cavanaugh

University of California, Davis
NA
RM

Richard Michelmore

University of California Davis
NA
RH

Robert H. Beede

UCCE Kings County, CA
NA
Thursday September 26, 2024 1:00pm - 1:15pm HST
Lehua Suite

1:15pm HST

NUTS 2 - Fatal Flaws of Experimental Almond Varieties and Selections
Thursday September 26, 2024 1:15pm - 1:30pm HST
The California almond industry has funded multiple, multi-site almond variety evaluation trials over the last several decades. These field trials have previously evaluated many of the varieties that are now the most widely planted in California. Although, field evaluation trials are helpful for revealing which varieties are promising, they are, perhaps, most valuable to the industry for revealing which varieties/selection have serious flaws and should not be planted by growers. Thirty named cultivars and numbered breeder selections were planted in three replicated commercial orchards across California’s Central Valley in 2014. Of these 30, as of April 2024, one numbered selection Y116-161-99 from the USDA has been commercially released as ‘Yorizane’. However, nine of the 30 varieties/selections were dropped from further evaluation in the trial in 2022 for a variety of reasons: low yield (five), lack of interest by the breeder (two), extremely early bloom timing (one), and poor harvestability (one). Of the 21 still being evaluated in 2024, many have one of these major flaws, or additional flaws, that will likely prevent commercial adoption, including a high percentage of double kernels, susceptibility to bacterial blast (Pseudomonas syringae pv. syringae), Botryosphaeria canker disease susceptibility, hull rot susceptibility, and a high percentage of kernel creases or twins, just to name some of the additional flaws. Even if a variety/selection has high yield, good kernel quality, and none of these major flaws documented after ten years of evaluation (e.g. Y117-91-03 from USDA), further observation in the UC trial sites or in the orchards of early adopters may reveal important flaws that prevent sustained and widespread variety adoption. This long-term challenge is why some believe it takes decades to prove a new scion variety. The wide diversity of potentially fatal flaws underscores the need for cultivar evaluation to take place by a third-party like UC Cooperative Extension in long-term replicated trials to reduce substantial financial risk to the grower to the greatest extent possible. Keywords: Prunus dulcis, almond, variety evaluation, breeding, nut crop
Speakers
LM

Luke Milliron

University of California Agriculture Natural Resources
Co-authors
PG

Phoebe Gordon

University of California Cooperative Extension
RD

Roger Duncan

UC Cooperative Extension
NA
Thursday September 26, 2024 1:15pm - 1:30pm HST
Lehua Suite

1:44pm HST

Public Horticulture/Hort Industry (PUBHORT/Hort Industry)
Thursday September 26, 2024 1:44pm - 3:45pm HST
Enhancing Public Garden Experiences: Utilizing QR Codes and Videos for Plant Identification and Education - Bailey Singleton
Educational Signage in a Community Garden can Assist in Volunteer Learning - Jonah Trevino
Marigolds - An Overlooked Cut Flower Alternative - Alessandro Holzapfel
Improving Military Community Reintegration: The Effects of Plant-related Jobs on Military Service Member Mental and Physical Health - Alicia Thomas
Evaluating the Impacts of Climate Change on Urban Tree Performance and Survival - Teagan Young
Managing Drift in Vegetable Operations: Extension Risk Management Herbicide Workshops - Kathryn Fontenot
Native Trees for Public Gardens: Building a University Teaching Collection for Increased Student Learning, Visitor Engagement, and Carbon Sequestration - Lauren Errickson
Future Directions of Horticultural Research Among Botanical Gardens and Arboreta in the United States - Michael Opgenorth

Moderator
avatar for Michael Opgenorth

Michael Opgenorth

National Tropical Botanical Garden
Thursday September 26, 2024 1:44pm - 3:45pm HST
Lehua Suite

1:45pm HST

PUBHORT/Hort Industry - Enhancing Public Garden Experiences: Utilizing QR Codes and Videos for Plant Identification and Education
Thursday September 26, 2024 1:45pm - 2:00pm HST
Public gardens play a crucial role in promoting horticultural education and appreciation. Proper plant signage can further enhance a visitor’s learning experience. This project provides partner gardens with trusted horticulture information while further utilizing Oklahoma Gardening content, produced by Oklahoma State University Extension. Oklahoma Gardening, a research-based, how-to gardening television show, airs weekly on Oklahoma Educational Television Authority (OETA), a PBS affiliate. This project created a virtual, educational experience for visitors of participating gardens. Eleven public gardens and educational demonstration gardens located in rural and urban settings throughout Oklahoma were provided with 5-15 signs depending on the size of the garden, the availability of in-season plant material, and the applicable video content. This approach leverages the recent widespread adoption of QR codes, allowing visitors to access plant information effortlessly from Oklahoma Gardening. Many of the selected gardens provide free entrance to the public, offering a horticultural experience to all. However, this can reduce the garden’s operation budget and limit their ability to provide adequate educational signage. The objective of this project is to help these public gardens increase their horticulture educational interpretation. These QR code signs not only provide gardens with seasonally appropriate plant identification signage but also offer visitors videos about the plants they are observing. Furthermore, for open-access public gardens it can be difficult to quantify visitation. By utilizing dynamic QR codes the quantity and time of scans is captured. This allows for tracking of the usage of each sign and which plants are most popular. This information is then shared with participating gardens. Public gardens are often visited by tourists as well. This project expands Oklahoma Gardening and OSU Extension beyond television and YouTube to reach an audience in the public garden space. The dynamic QR code scans provide the phone’s registered city, state, and country, giving approximate geographic locations of garden visitors. After a year of placing the signs, we have identified clicks from 23 states, and 5 additional countries. This project was funded by Oklahoma Department of Agriculture, Food, and Forestry Specialty Crop Block Grant.
Speakers
BS

Bailey Singleton

Oklahoma State University
Co-authors
CH

Casey Hentges

Oklahoma State University
NA
Thursday September 26, 2024 1:45pm - 2:00pm HST
Lehua Suite

2:00pm HST

PUBHORT/Hort Industry - Educational Signage in a Community Garden can Assist in Volunteer Learning
Thursday September 26, 2024 2:00pm - 2:15pm HST
Volunteering issues in community gardens have been an ongoing problem and have resulted in high turnover and untrained volunteers that may not have the skills to appropriately staff a community garden. The problem of having to train or have dedicated staff at a garden to assist volunteers is that often community gardens are not funded, or garden staff are stretched too thin. To inspect factors in volunteerism in community gardens, researchers sent out a ten-question survey to head community garden leaders (N=51) across the U.S. Overall, researchers found that many gardens perceive educational opportunities and the people that attend the garden as successful elements, while volunteer retention and education, along with signage issues, were the most prevalent problem. Finally, when asked about signage, most signs turned out to be purely informative and attractive, with few playing educational roles. Researchers concluded that educational signage may play an important role in the garden that many community gardens are missing. To understand further how educational signage plays a role in people’s understanding of a subject, researchers have developed another survey that is currently being distributed to the public. The data from this survey will allow researchers to more effectively use signage to not only attract but educate and train volunteers to relieve some of the burden from community garden staff.
Speakers
JT

Jonah Trevino

Texas Tech University
NA
Co-authors
CS

Catherine Simpson

Texas Tech University
NA
LF

Laura Fischer

Texas Tech University
NA
LT

Leslie Thompson

Texas Tech University
NA
VB

Vikram Baliga

Texas Tech University
NA
Thursday September 26, 2024 2:00pm - 2:15pm HST
Lehua Suite

2:15pm HST

PUBHORT/Hort Industry - Marigolds - An Overlooked Cut Flower Alternative
Thursday September 26, 2024 2:15pm - 2:30pm HST
Especially the floral industry is dependent on fashion trends and changes in taste that dictate the colors and styles of arrangements. As it turns out, when it comes to marigold cut flowers, certain customers have been traditionally underserved in the southeastern United States. Research conducted by the Louisiana State University and Mississippi State University indicate that Marigolds are not only a very viable alternative to traditional cut flowers but also a worthwhile investment for commercial growers. Further research indicates that specific cultures and religions prefer marigolds for celebrations and holidays representing a relatively large customer base with considerable purchasing power that has previously gone unnoticed by the floral industry in the southeastern United States. Findings suggest marigolds have the potential to increase the floral industry’s market share and attract new customers that it previously failed to attract. Additionally, many celebrations and holidays for which marigolds are desired are during a time of the year when demand for flowers is typically low. Marigolds should therefore be considered for season extension.
Speakers
AH

Alessandro Holzapfel

Louisiana State University Agricultural Center
Co-authors
AA

Achyut Adhikari

Louisiana State University Agricultural Center
NA
KF

Kathryn Fontenot

LSU AgCenter
Thursday September 26, 2024 2:15pm - 2:30pm HST
Lehua Suite

2:30pm HST

PUBHORT/Hort Industry - Improving Military Community Reintegration: The Effects of Plant-related Jobs on Military Service Member Mental and Physical Health
Thursday September 26, 2024 2:30pm - 2:45pm HST
Military members are a unique and diverse group making up 7% of the U.S. population. After completing their military service many return home and struggle with reintegration back into civilian life due to mental and physical ailments they obtained during enlistment. One of the first steps of civilian reintegration is acquiring a job. A type of job that military members enter is in plant-related fields. Research on the passive and active interaction with plants and its benefits, has been conducted extensively. However, it is not yet known how specific jobs that require working with plants or being in nature can help improve military member health and if they have therapeutic benefits. To evaluate this, part 1 of an online survey ascertained demographics and part 2 was created based on the National Veteran’s Survey and the VR-36 which looked at participants’ physical (PCS) and mental wellness (MCS). Results show that most of the military participants (N=148) were in the 25-30 year and 40-50-year-old range, Caucasian (70.9%) males (68.9%) involved in Army (44.6%) and Marine (24.3%) branches of the military and honorably discharged or retired. Military members in plant-related jobs scored in the top 3 job categories for PCS (49.1) and MCS (45.0), while Health related jobs were top for MCS (53.6) and those retired were top for PCS (49.7). Overall, those in plant, health, and retired jobs described them as relaxing, easy, and physical. Military in rural locations also had lower MCS in comparison to those living in urban centers. The findings from this research suggest that plant-related jobs could offer military members an opportunity to improve their mental and physical health, while helping with job retention and community reintegration.
Speakers
AT

Alicia Thomas

Texas Tech University
Thursday September 26, 2024 2:30pm - 2:45pm HST
Lehua Suite

2:45pm HST

PUBHORT/Hort Industry - Evaluating the Impacts of Climate Change on Urban Tree Performance and Survival
Thursday September 26, 2024 2:45pm - 3:00pm HST
Climate change is expected to lead to the increased frequency and intensity of natural disasters, which will adversely affect urban tree populations. As a result of rising surface temperatures, USDA Hardiness Zones are projected to shift northward. Healthy urban trees can offer benefits which may offset some of the effects of warming. Therefore, species adaptability to urban conditions needs to be considered, and we need to understand the predicted impacts of warming better in order to design and plant more resilient urban forests. Thus, in the Fall of 2022, protocols began developing to evaluate the following areas of concern: 1: Identify underutilized tree species that might perform well in future climates. A state-wide survey was distributed to green industry professionals to guide species selection for field trials across three hardiness zones in Florida (8b, 9a, and 10b). 2: Analyze the variability of commonly used irrigation technologies on tree establishment. The project compares two commonly used irrigation bags (i.e., TreeDiaper and Treegator) to hand watering to determine labor inputs, time to establishment, and overall tree performance. 3: Determine the effects of increased temperatures on tree species commonly planted in Florida. Temperature-controlled greenhouse experiments will be used to determine the heat tolerance of 6 tree species based on future climates. 4: Analyze parking lot plantings and evaluate the impact of the mitigation of the urban heat island effect. Several randomly selected parking lots in Florida will be looked at to determine their suitability for planting based on the adverse growing conditions associated with urban heat islands. The above studies offer a proactive approach to better understanding the potential effects of warming and provide practical solutions to minimize the impact.
Speakers
avatar for Teagan Young

Teagan Young

PhD Research Assistant, University of Florida
Hi there! I come from the lovely town of Kalamazoo, MI, where my love for taking care of nature through horticulture first took root. In 2019, I made my way down to Gainesville, FL, enticed by the opportunity to join the respected University of Florida's Environmental Horticulture... Read More →
Co-authors
GH

Gail Hansen

University of Florida
NA
LW

Laura Warner

University of Florida
NA
RK

Ryan Klein

University of Florida
NA
SW

sandra wilson

University of Florida
Dr. Sandra Wilson is a Professor of Environmental Horticulture at the University of Florida’s main campus in Gainesville. She received B.S. and M.S. degrees from the University of Delaware and a Ph.D. in Plant Physiology from Clemson University. Dr. Wilson completed postdoctoral... Read More →
Thursday September 26, 2024 2:45pm - 3:00pm HST
Lehua Suite

3:00pm HST

PUBHORT/Hort Industry - Managing Drift in Vegetable Operations: Extension Risk Management Herbicide Workshops
Thursday September 26, 2024 3:00pm - 3:15pm HST
Herbicide drift from the site of application into non-target areas can be devastating to the environment and to neighbor operations. Crop injury will occur from drift and improper management of herbicides within an operation. Environmental conditions, applicator off-label usage and accidents are often the cause of herbicide drift. Prevention and communication are the most important strategies in managing off target application of herbicides. Two workshops were held in Louisiana. Vegetable producers, Department of Agriculture inspectors, county agents, and crop producers were invited to both workshops. Pre and post tests were given to all participants to measure general herbicide application and rule knowledge. The workshops consisted of fields showcasing tomatoes and squash with 4 herbicides sprayed on them to showcase what drift looks like. Control (non-sprayed plants) were also in the field. All plots were replicated but only half labeled. The participants learned what the symptoms looked like, then worked in teams to identify the non-labeled plots. Participants also learned how to properly clean tanks and nozzles, as well as listened to speakers about the economic loss from off target herbicide drift, and rules and regulations from Louisiana Department of Ag and Forestry specialists. 77% of the participants could identify round up damage by the end of the workshop, whereas only 40% could identify 2, 4D damage. All participants increased knowledge in tank cleaning and cross contamination prevention by the end of the workshop. and All participants gained knowledge in the documentation of crop loss economic questions at the end of the workshops.
Speakers
KF

Kathryn Fontenot

LSU AgCenter
Co-authors
AH

Alessandro Holzapfel

Louisiana State University Agricultural Center
MB

Maria Bampasidou

LSU AgCenter
NA
RS

Ronald Strahan

LSU AgCenter
NA
Thursday September 26, 2024 3:00pm - 3:15pm HST
Lehua Suite

3:15pm HST

PUBHORT/Hort Industry- Native Trees for Public Gardens: Building a University Teaching Collection for Increased Student Learning, Visitor Engagement, and Carbon Sequestration
Thursday September 26, 2024 3:15pm - 3:30pm HST
Changing climate patterns challenge the long-term health and survivability of common mid-Atlantic U.S. tree species, including climax species such as oaks, elms, and beeches. Evidence of tree loss in natural and managed ecosystems and residential areas demonstrates the need for public gardens to consider alternative species that will adapt to changing conditions, maximize carbon sequestration, and provide aesthetic value. University-affiliated Rutgers Gardens has long served to demonstrate landscape best practices and species selection for students, industry professionals, and homeowners; additionally, carbon sequestration has become a primary function. Continuing a tradition of education, Rutgers Gardens is creating a Native Trees teaching collection including over one hundred native species selected for their ecosystem functions, ecological niche, and landscape aesthetics, on an approximately four-acre site with the goal of maximizing carbon sequestration and educational value. Selected specimens include those native to New Jersey and the wider mid-Atlantic region and/or southeastern United States. This allows for a comprehensive collection that supports larger ecosystem functions, especially as tree species composition in the broader region is likely to shift with time. As major tree species are lost due to climate-influenced changes in pest, disease, and environmental pressures, preparing for continuous carbon sequestration by including species likely to thrive in our changing climate will maximize the environmental benefit. By including a mix of small, medium, and large (at maturity) trees, the design maximizes ecosystem niches occupied throughout the planting area and provides a comprehensive demonstration for students, homeowners, and industry professionals, modeling native trees for consideration in landscape plantings throughout the state. Specimens include straight species, as well as cultivars within the genera to demonstrate variability in true native trees and “nativars,” or cultivars of native trees. A density of approximately 25 trees per acre planted allows for the integration of new trees with existing specimens, including trees and shrubs that represent historical iterations of present-day Rutgers Gardens, and accommodates the design of accessible paths and gathering spaces between plantings to maximize educational opportunities. Public gardens present many opportunities for education and demonstration, especially within a university setting. Yet, challenges exist when considering complex land use history, student and faculty needs, visitor expectations, and the interests of diverse stakeholders such as members, volunteers, and staff of public gardens. Lessons learned include the importance of positive and clear communication among stakeholders to ensure project benefits are recognized and shared for educational and ecological success in public spaces.
Speakers
LE

Lauren Errickson

Director of Rutgers Gardens & Campus Stewardship, Rutgers, the State University of New Jersey
Co-authors
MM

Maxine Marvosa

Rutgers, the State University of New Jersey
NA
Thursday September 26, 2024 3:15pm - 3:30pm HST
Lehua Suite

3:30pm HST

PUBHORT/Hort Industry - Future Directions of Horticultural Research Among Botanical Gardens and Arboreta in the United States
Thursday September 26, 2024 3:30pm - 3:45pm HST
Botanical gardens and arboreta maintain globally important collections for conservation and education with efforts to constantly strive for excellence in propagation, cultivation, and collection preservation. Methods of cultivating plants, learning from successes and challenges, with the ability to disseminate that knowledge is paramount for improving techniques and outcomes. However, the underlying field of horticultural research is not well defined, and results of plant cultivation techniques are often only shared informally rather than published. We explored how horticultural research practitioners perceive the field of horticulture research and excellence, how they are involved, and the most urgent needs of future horticultural research among gardens and arboreta. We conducted an internet-based survey of the status of horticultural research amongst the United States members of the American Society for Horticultural Research (ASHS), American Public Garden Association (APGA), Botanical Garden Conservation International (BGCI), and the Interactive Community of Arboreta (ArbNet), Level II, III, and IV members. 128 respondents from 116 institutions across 34 of the United States completed the survey. As conservation needs, changing agricultural paradigms, and climate change impacts continue to increase, we find future research needs are increasingly holistic and focus on species and variety conservation, ecology, and mitigating pests and diseases. The respondents were variously involved in horticulture research and the main challenges were funding, time, and personnel resources. Horticultural knowledge is largely practical and shared informally and there is a need for recognition and means of sharing practical research as well as technical research. This study presents a new framework for horticultural research supporting the horticulture community with the conceptualization, communication, and implementation of horticultural research.
Speakers
avatar for Michael Opgenorth

Michael Opgenorth

National Tropical Botanical Garden
Co-authors
DR

David Rae

Stanley Smith (UK) Horticultural Trust
NA
JA

Julia Avila

National Tropical Botanical Garden
NA
NR

Nina Ronsted

National Tropical Botanical Garden
NA
SB

Sarah Bryce

National Tropical Botanical Garden
NA
Thursday September 26, 2024 3:30pm - 3:45pm HST
Lehua Suite

4:00pm HST

Interest Group Session: Climate Ready Landscape Plants
Thursday September 26, 2024 4:00pm - 6:00pm HST
The overall goal of this session is to highlight the latest advancements from the USDA Agricultural Marketing Service Specialty Crop Multi-State Program funded project titled “Climate Ready Landscape Plants”.

Coordinator/Moderator
  • Youping Sun, Utah State University, Department of Plants, Soils & Climate, Logan, Utah, United States
Speaker/Participant(s)
  • Jared Sisneroz, UC Davis
    Climate Ready Landscape Plants Trialed in Davis, CA
    Summary: To develop landscape irrigation recommendations, a field trial evaluated 22 taxa of landscape plants under three levels of deficit irrigation. Taxa included cultivars of Hibiscus syriacus, Nandina domestica, Rosa spp., and Salvia spp., among other common perennials and shrubs. Taxa were planted in a grid pattern with 2 meters spacing between rows and plants. Several larger taxa were planted in an adjacent field with 3 meters spacing. After an initial growing season of regular irrigation to establish the plants, from April to October 2022, plants were irrigated with one of three deficit irrigation treatments equal to 80%, 50%, or 20% of ETo. Treatments functioned like a crop coefficient in modifying daily ETo values. Irrigations occurred whenever this threshold was reached, with the volume of water applied being equal to 50% of PAW. The volume applied at each irrigation was constant across treatments with the frequency between irrigations varying by treatment. As a result, the 80% treatment was irrigated most frequently with the 20% treatment was irrigated thrice during the deficit period. Monthly during the deficit period, each plant was rated on six categories of aesthetic quality. Aesthetic performance between the treatments was compared using an ANOVA in conjunction with Tukey’s HSD post-hoc test in R. A majority of the taxa evaluated maintained acceptable aesthetic quality ratings on the lowest irrigation treatment. Two taxa evaluated, Lagerstroemia ‘SMNLCIBF’ Center Stage® Red and Rosa ‘ChewPatout’ Oso Easy® Urban Legend achieved high levels of aesthetic performance on the 20% treatment.
  • Amelia Keyser-Gibson and Soo-Hyung Kim, University of Washington, United States
    Variation in Landscape Plant Aesthetics, Growth, and Physiology to Deficit Irrigation Across the Western U.S. (20 mins)
    Summary: Climate change is causing more frequent and severe droughts in the Western U.S., while concurrently, about 70% of urban water use is dedicated to landscape irrigation. Therefore, water conservation techniques in the horticultural space, such as planting water-use-efficient landscape plants, will be essential to reduce irrigation consumption. Five different taxa, Hibiscus syriacus ‘Gandini Santiago’ Purple Pillar®, Hibiscus syriacus 'ORSTHIB5x1' PPAF, Rosa ‘Meibenbino’ Petite Knock Out®, Rosa ‘ChewPatout’ Oso Easy® Urban Legend®, and Vitex ‘SMVACBD’ Blue Diddley®, were subjected to one of three water deficit treatments in six sites: Tucson, Arizona; Davis, California; Irvine, California; Aurora, Oregon; Logan, Utah; and Seattle, Washington. Plants were rated on foliage quality, flowering, pest tolerance, disease resistance, vigor, and overall appearance. Growth measurements were also taken to calculate a plant growth index and relative plant growth index. Stomatal conductance and the efficiency of Photosystem II (ΦPSII) were measured when the treatments were in full effect and compared to the aesthetic ratings to get a broad picture of plant health. Overall, at individual sites, treatment did have a significant effect on aesthetic qualities and growth of specific taxa. Additionally, between sites, aesthetic qualities and growth differed significantly. Stomatal conductance and ΦPSII were not higher in the high treatment for all taxa and differed significantly between most sites. Additionally, higher gs and ΦPSII did not correlate with higher aesthetic ratings and growth. Our results highlight the importance of climate-specific plant selection for reducing landscape water use while achieving satisfactory aesthetic qualities and growth of landscape plants.
  • Ursula Schuch, University of Arizona
    Climate Ready Landscape Plants Trialed in Tucson, AR
    Summary: : Fifteen taxa of shrubs growing in a field in Tucson, Arizona were irrigated with three levels of irrigation based on local reference evapotranspiration (ETo) to assess growth and plant quality. Plants established during 2021 under 80% of ETo and in 2022 were irrigated at 20%, 50%, or 80% of ETo. Irrigation was applied 2, 9, and 15 times between April 1 and October 31, 2022, for the low, medium, and high irrigation, respectively. Best performing plants were Dodonaea viscosa ‘Emerald Ice’, Eremophila glabra ssp. carnosa ‘Winter Blaze’, Ericameria laricifolia ‘Aguirre’, Hamelia patens ‘Sierra Red’, Leucophyllum frutescens ‘San Antonio Rose’, and Tecoma ‘Red Hot’ which maintained a high overall rating at the low irrigation treatment. Irrigation did not affect plant growth of these taxa from April to October. Monthly visual quality assessment of some taxa was temporarily affected by irrigation, however, all performed acceptably or better at the low irrigation. Two field days were held in August and October 2022 where green industry professionals were invited to rate plant performance of one representative plant from each taxon and irrigation treatment. Most participants’ favorite plants included the taxa with consistently high overall ratings. The best performing taxa are low water use shrubs that can grow in the landscape with 20% of ETo in the low desert in Arizona. However, some may benefit from additional irrigation during the hottest time of the year for optimum performance.
  • Natalie Levy, South Coast Research & Extension Center, The University of California Agriculture and Natural Resources
    Climate Ready Landscape Plants Trialed in Irvine, CA
    Summary: As climate extremes, population growth, and agricultural/industrial water demands continue to increase, urban landscapes are an essential area where water conservation efforts must be improved. Deficit irrigation trials of ornamental plants began at the University of California, Davis (UCD) in 2004 and became the University of California Landscape Plant Irrigation Trials (UCLPIT™). In 2016, it was replicated at UC Agriculture and Natural Resources’ South Coast Research and Extension Center (SCREC) in Irvine, California. Researchers observed differences in performance between sites on selected taxa indicating that plant species will have irrigation requirements that vary in different climates. In 2019, the UCLPIT methodology was expanded to multiple western climate zones and soil types in Arizona, Utah, Oregon, and Washington through a USDA Specialty Crops Multi-State Program grant. Two seasons of data were collected in 2022 and 2023. The overall appearance and plant growth of 12 shared ornamental plants to deficit irrigation were investigated. Eight plants per species were randomly assigned to 1 of 3 deficit irrigation frequencies, calculated based on 80% reference evapotranspiration (ETo) (high), 50% ETo (moderate), and 20% ETo (low). Overall appearance and plant growth were evaluated monthly during April to October in both 2022 and 2023 at SCREC. There were variations in overall appearance across species under deficit irrigation in both years of the trial. Evapotranspiration rates were higher in 2022 and more irrigation events occurred for all treatments. The Philadelphus madrensis ‘ORSTPHILx2’ (Swan Lake® mock orange) and the Philadelphus lewisii 'Blizzard' (Blizzard mock orange) species evaluated in 2022 had significantly greater overall appearance on the moderate treatment than the low treatment.
Moderator
YS

Youping Sun

Dr. Sun is an Associate Professor of Landscape Horticulture whose research focuses on understanding the whole-plant response to water stress, with an emphasis on water conservation, and developing protocols to produce native plants. He is the principal investigator for the ‘Climate... Read More →
Speakers
JS

Jared Sisneroz

UC Davis
Mr. Sisneroz is the project manager of the UC Landscape Plant Irrigation Trials (UCLPIT) and the ‘Climate Ready Landscape Plants’ programs. He specializes in landscape plant water-use efficiency research and water resource management.
AK

Amelia Keyser-Gibson

University of Washington
SK

Soo-Hyung Kim

Dr. Kim is a Professor and Plant Ecophysiologist whose research focuses on how plants interact with their environment at the whole-plant scale. He is the principal investigator for the ‘Climate Ready Landscape Plants’ project at the University of Washington.
US

Ursula Schuch

University of Arizona
Dr. Schuch is a Professor and Extension Specialist in Environmental Horticulture in the School of Plant Sciences. Dr. Schuch’s research focuses on plant selection and management strategies to conserve water, maintain plant health, and aesthetic function. She is the principal investigator... Read More →
NL

Natalie Levy

Dr. Levy is an Associate Specialist for Water Resources at the South Coast Research and Extension Center. She specializes in landscape plant water-use efficiency research, water resource management, and water pollution prevention/mitigation.
Thursday September 26, 2024 4:00pm - 6:00pm HST
Lehua Suite
 
Friday, September 27
 

9:59am HST

Tropical Horticultural Crops (TROP)
Friday September 27, 2024 9:59am - 10:45am HST
Advancing Cocoa Yield Forecasting in Ecuador Using Machine Learning and Field Data Integration - Daniel Mancero
Maturity Stage at Harvest Modulates Fruit Softening and Quality of Jackfruit - Zor Singh
Growing Papaya in Mississippi - Guihong Bi
Moderator
GB

Guihong Bi

Mississippi State University
Friday September 27, 2024 9:59am - 10:45am HST
Lehua Suite

10:00am HST

TROP - Advancing Cocoa Yield Forecasting in Ecuador Using Machine Learning and Field Data Integration
Friday September 27, 2024 10:00am - 10:15am HST
Accurate prediction of cocoa yields is critical for farmers, governments, and industry as it influences logistics and supports decision-making. In tropical agriculture, there has been a recent trend toward integrating sensor technology, data science, and machine learning to enhance management and boost crop production. However, cocoa yield prediction models rely on the quality and availability of public datasets and genetic differences among cocoa genotypes. Moreover, current cocoa models require technical skills for satellite image processing or a significant investment in sensors and software. Different statistical models in cocoa predict yield independently of physiological processes or disease pressure. Therefore, we propose a mechanistic model that uses historical yield and weather data from 2010 to 2023 and the in-field sampling from 61 orchard plots from four farms in Guayas, Ecuador. Time series measures of cocoa pods and disease incidence per tree in the plots were recorded for the 2023 and 2024 growing seasons. Cocoa pod counts and diseased pods, as well as tree photographs for biomass calculation, were recorded using a customized mobile application. Ecuador´s cocoa production in this location has a bimodal annual distribution, with the highest peak following the start of the rainy season. Moniliasis disease also presented the highest incidence within the next two months of precipitaion peaks. Several varieties of cocoa are grown in Ecuador, but production is dominated by two main groups: Fine cocoa or national flavor and CCN-51. The national type of cocoa is characterized by its unique flavor profile. However, it is prone to diseases and has a lower yield. To overcome these challenges, our study aims to develop a machine learning-based model geared towards Ecuador's distinct national type cocoa varieties, taking into account local climate patterns, soil characteristics, biomass, and direct cocoa pod field counting. The analysis reveals that cocoa yield variability is affected mainly by moniliasis disease incidence, tree biomass, and environmental factors such as temperature, solar radiation, and precipitation. In contrast, soil texture, pH, and electrical conductivity had minor variations and a negligible effect on yield changes. The proposed model was compared with other machine learning algorithms based on Mean Absolute Error and Mean Square Error. The validation phase, employing the Mean Absolute Percentage Error, indicates our model's substantial predictive accuracy with a confidence interval of 73.4 percent at the 0.1 significance level and confirms the model's effectiveness in forecasting cocoa yields under Ecuadorian conditions.
Speakers
DM

Daniel Mancero

UNIVERSIDAD AGRARIA DEL ECUADOR
Fruit researcher with experience in multidisciplinary projects for plant protection and plant breeding
Co-authors
MA

Maritza Aguirre

UNIVERSIDAD AGRARIA DEL ECUADOR
NA
NV

Nestor Vera

UNIVERSIDAD AGRARIA DEL ECUADOR
NA
YG

Yoansy Garcia

UNIVERSIDAD AGRARIA DEL ECUADOR
NA
Friday September 27, 2024 10:00am - 10:15am HST
Lehua Suite

10:15am HST

TROP - Maturity stage at harvest modulates fruit softening and quality of jackfruit
Friday September 27, 2024 10:15am - 10:30am HST
The maturity stage at harvest influences the postharvest quality and storage life of fruit. Harvesting jackfruit (Artocarpus heterophyllus Lam.) at the optimum maturity stage is more important due to the very large size of the fruit. Therefore, the present investigation was conducted to determine the impact of four different maturity stages on physicochemical parameters and fruit-softening enzymes in two jackfruit genotypes (Accession 242 and Accession 341). Fruit for the initial three stages were harvested at 10 days intervals commencing 90 days after flowering (DAF), while fruit for the final stage were harvested based on traditional maturity parameters (142 and 153 DAF) in Accession 341 and Accession 242 respectively. Results indicated an increase in fruit size, seed and bulb weight with the advancement of fruit maturity in both accessions. Moreover, there was a concurrent decline in spine density and an increase in spine flatness with the progression of fruit maturity. Whilst pulp percentage increased, there was a decrease in rag and core percentage at advanced maturity stages. However, peel and seed percentage were not influenced significantly by the advancement of fruit maturity. Additionally, there was a decrease in L* value with a concomitant increase in a*, b*, and C* values of the bulb with the advancement of fruit maturity. In both accessions, bulb firmness, and moisture content were highest in fruit harvested at 90 DAF. The decline in bulb firmness was associated with higher activities of polygalacturonase, pectin methyl esterase, cellulase, and pectate lyase. In both accessions, soluble solid content (SSC), DPPH radical scavenging activity, total flavonoids, and ascorbic acid content were higher in fruit harvested during the last stages of maturity while titratable acidity and total phenolics content were comparatively lower in advanced maturity stages. These findings highlight that the earlier stages (90 and 120 DAF) are suitable as meat alternatives due to better texture, while the most favourable stages for fresh consumption are 142 ± 4.7 and 153 ± 5.7 DAF in ‘Accession 341’ and ‘Accession 242’ due to better colour, higher pulp percentage, higher SSC and antioxidant activity, respectively.
Speakers
ZS

Zora Singh

Foundation Professor Horticultural Science, Edith Cowan University
Zora Singh is a Foundation Professor Horticultural Science in the School of Science with noteworthy expertise in Production technology and Postharvest physiology of fresh horticultural produce, undergraduate teaching and research training to domestic and international MSc and PhD... Read More →
Co-authors
AW

Andrew Woodward

Edith Cowan University
NA
EA

Eben Afrifa-Yamoah

Edith Cowan University
NA
HM

Hafiz Muhammad Shoaib Shah

Edith Cowan University
NA
JK

Jashanpreet Kaur

Edith Cowan University
MS

Muhammad Sohail Mazhar

Department of Industry, Tourism and Trade
NA
Friday September 27, 2024 10:15am - 10:30am HST
Lehua Suite

10:30am HST

TROP - Growing papaya in Mississippi
Friday September 27, 2024 10:30am - 10:45am HST
Papaya (Carica papaya) is an herbaceous perennial plant native to the tropical Americas. It thrives in tropical and subtropical climates. While the United States is the world’s largest papaya importer, it also cultivates a modest number of papayas, primarily in Hawaii, California, Texas, and Florida. The subtropical climate in Mississippi offers favorable conditions for papaya cultivation. However, frosts in late fall or early spring could pose threats to both plants and fruits. Appropriate cultivar selection and management strategies are critical for successful papaya production in MS. Currently, limited information is available on growing papayas in MS. The objective of this study was to investigate the potential of growing papaya as an alternative crop for specialty crop growers in MS. Preliminary data suggest that papaya plants can grow well in Mississippi. Different cultivars exhibited variations in plant size and vigor. Plants produced papaya fruits with variations in fruit number, size, and shape, as well as timing to fruiting among different cultivars. However, the relatively shorter growing season in MS compared to tropical climates resulted in insufficient time for most fruits to ripen before the onset of frost in late fall. Further research will involve evaluating additional cultivars, adjusting production schedules, employing season extension techniques, and assessing economic feasibility.
Speakers
GB

Guihong Bi

Mississippi State University
Co-authors
JL

Jacob Land

Mississippi State University
NA
TB

Taylor Blaise

Mississippi State University
NA
TL

Tongyin Li

Mississippi State University
NA
Friday September 27, 2024 10:30am - 10:45am HST
Lehua Suite

10:59am HST

Tropical Horticultural Crops (TROP)
Friday September 27, 2024 10:59am - 11:50am HST
Comparing The Effect Of Potyviruses On The Yield Of Different Generations Of Beauregard Sweetpotato Variety - Sathish Ponniah
“Midnite” and “Festival”: Combining Caribbean and African Hibiscus sabdariffa - Thomas Zimmerman
Metabolomic Survey of Puffy Skin Date Fruit - Yoko Hiraoka
Identifying the formation of aroma compounds in mango using a multi-omics approach - Yu Wang
Establishment of Avocado trees in the United States Virgin Islands - Samuel Joseph
Speakers
SJ

Samuel Joseph

University of the Virgin Islands
NA
Friday September 27, 2024 10:59am - 11:50am HST
Lehua Suite

11:00am HST

TROP - Comparing The Effect Of Potyviruses On The Yield Of Different Generations Of Beauregard Sweetpotato Variety
Friday September 27, 2024 11:00am - 11:10am HST
Sweetpotatoes (Ipomoea batatas) have become increasingly popular over the last two decades. It is higher in beta-carotene than many other vegetables and a source of potassium, fiber, and vitamins A and C. Orange-fleshed varieties have a significant role in addressing vitamin A deficiencies, especially in pregnant women and children in developing countries. Sweetpotatoes are vegetatively propagated and susceptible to viruses that accumulate with each planting cycle (generation), leading to cultivar decline. This can affect the yield and quality of the sweetpotato roots. Over 30 viruses have been identified in sweetpotato. In U.S. commercial production fields, four potyviruses such as Sweetpotato feathery mottle virus (SPFMV), Sweetpotato virus G (SPVG), Sweetpotato virus 2 (SPV2), and Sweetpotato virus C (SPVC) are often commonly found. Potyviruses are aphid transmitted in a non-persistent manner. The potyvirus, Sweetpotato feathery mottle virus (SPFMV), is, by far, the most common sweetpotato virus. The objectives of the study are to compare the level of virus infection in five different generations (G1, G2, G3, G4, G6) with the yield performance in the Beauregard variety under field conditions. The different generation roots were collected from the previous experiments, and slips were multiplied under greenhouse conditions of the University of Arkansas at Pine Bluff (UAPB) farm. The slips were planted 12 inches apart with a 30-inch row spacing in four replications using a randomized block design during the summer of 2023. The roots were collected and cured to measure the various yield parameters like total marketable yield, U.S. No. 1, Jumbos Canners, and Culls. The random roots were selected to quantify the viral infections across the five generations using multiplex Reverse Transcription-Polymerase Chain Reaction (mRT-PCR). We observed significant differences in the U.S. No. 1 roots and Canners across the generations. In total marketable yield, 42.5% reduction was observed between the younger generation (G1, G2) and the older (G6) generation. Here, SPFMV was found to be dominant across the generations. Overall, a higher rate of virus infections was detected in the older generation (G6) than in younger generations (G1, G2).
Speakers
Friday September 27, 2024 11:00am - 11:10am HST
Lehua Suite

11:10am HST

TROP - “Midnite” and “Festival”: Combining Caribbean and African Hibiscus sabdariffa
Friday September 27, 2024 11:10am - 11:20am HST
Hibiscus sabdariffa, regionally referred to as sorrel, is a popular annual fruiting crop in the Caribbean. During the winter holiday season, sorrel calyxes are used for making flavorful and refreshing deep crimson red juices and teas. Through years of breeding and selection among Caribbean and African lines, from Ghana and Nigeria, the University of the Virgin Islands developed and released two new cultivar “Midnite” and “Festival”. “Midnite” has 20% greater production over standard Caribbean cultivars. The dark crimson-black calyxes, of both new cultivars, are full of anthocyanins and bioflavonoids. “Festival” begins bearing a month earlier than photoperiodic cultivars and production can extend to early May. Being day-neutral, “Midnite” can be grown year-round but has heavier production during late summer to late Spring. “Midnite” is being widely used in the U.S. Virgin Islands and has potential to expand its use in other commercial industries.
Speakers
TZ

Thomas Zimmerman

University of the Virgin Islands School of Agriculture
Friday September 27, 2024 11:10am - 11:20am HST
Lehua Suite

11:20am HST

TROP - Metabolomic Survey of Puffy Skin Date Fruit
Friday September 27, 2024 11:20am - 11:30am HST
Date palm, Phoenix dactylifera L., is one of the oldest fruit crops grown in the arid regions of the Arabian Peninsula, North Africa and the Middle East and plays a significant role in the economy, society, and environment in these areas. ‘Medjool’ is considered one of the most desirable date varieties worldwide. Skin separation, also known as “puffy skin”, is a widespread phenotypic phenomenon mostly seen in soft varieties such as‘Medjool’ and ‘Barhee’. Skin separation is a market defect that is a commercial disadvantage. In this study, we conducted a metabolomic study of 'Medjool’ fruits at the date genebank maintained in Thermal, California by the United States Department of Agriculture Agricultural Research Service. Date fruit were harvested at the tamar stage (the fruit development stage in which the puffy skin phenotype develops). The metabolomes found in mature date fruits exhibiting non-puffy and puffy phenotypes were characterized. In this study, targeted central carbon metabolism analysis was carried out to identify 126 total metabolites with 95 significant metabolites (p-value < 0.05) (75.4%). Principal Component Analysis (PCA) was carried out, revealing that specific metabolites were associated with the non-puffy skin phenotype, and other metabolites with the puffy skin phenotype.. These metabolomes included those associated with skin elasticity and integrity, supporting studies suggesting the involvement of mechanical properties of date fruit skin.
Speakers
YH

Yoko Hiraoka

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

Esteban Rodriguez

National Clonal Germplasm Repository for Citrus and Dates, United Stated Department of Agriculture, Agricultural Research Service, U.S.
NA
RK

Robert Krueger

National Clonal Germplasm Repository for Citrus and Dates, United Stated Department of Agriculture, Agricultural Research Service, U.S.
NA
Friday September 27, 2024 11:20am - 11:30am HST
Lehua Suite

11:30am HST

TROP - Identifying the formation of aroma compounds in mango using a multi-omics approach
Friday September 27, 2024 11:30am - 11:40am HST
Mango (Mangifera indica L.) is a fruit renowned for its delectable flavor, making it a staple in tropical and subtropical regions and the second most significant fruit crop in horticulture. Despite its widespread popularity, the specific compounds responsible for its distinctive aroma remain elusive. Our study aimed to bridge this gap by employing untargeted metabolomics and proteomics approaches to investigate aroma compound biosynthesis in three mango cultivars: 'Ah Ping', 'Rosa', and 'Rosigold'. Through integrated metabolomics and proteomics analysis, we identified key pathways and enzymes involved in aroma compound biosynthesis. Fatty acid metabolism, amino acid metabolism, pentose and hexose metabolism, and terpenoid metabolism emerged as pivotal pathways influencing mango flavor diversity. In 'Ah Ping', upregulation of lipoxygenase, hydroperoxide lyase, and alcohol dehydrogenase led to the accumulation of C6 and C9 volatile compounds, contributing to its distinct aroma profile. Conversely, 'Rosa' exhibited varied contents of straight-chain volatile compounds facilitated by the upregulation of enzymes involved in fatty acid degradation. Amino acid metabolism played a crucial role, with glutamate, valine, and phenylalanine serving as precursors for the biosynthesis of butyl esters and aromatic compounds in all three cultivars. Differential expression of enzymes such as aminotransferase and decarboxylase further modulated aroma compound production. Additionally, variations in furan and pyran volatile compounds were linked to differentially expressed enzymes in pentose and hexose metabolism. Our findings provide a comprehensive metabolic and proteomic map elucidating the biosynthesis of specific aroma compounds across mango cultivars. By unraveling the molecular mechanisms underlying mango flavor, this study offers valuable insights for breeding programs aimed at enhancing mango varieties with superior flavor quality. Overall, our research sheds light on the interplay between metabolism and aroma compound biosynthesis in mango, paving the way for targeted breeding strategies and improved mango flavor profiles.
Speakers
YW

Yu Wang

University of Florida
Co-authors
JH

Jonathan H Crane

University of Florida, TREC
XL

Xin Liu

University of Florida
NA
XW

Xingbo Wu

Chair 2023-2024, University of Florida
NA
Friday September 27, 2024 11:30am - 11:40am HST
Lehua Suite

11:40am HST

TROP - Establishment of Avocado trees in the United States Virgin Islands
Friday September 27, 2024 11:40am - 11:50am HST
Avocado (Persea americana Mill.), also known as pear in the Caribbean, is a staple fruit in the United States Virgin Islands (USVI) and has one of the fastest expanding markets in Europe and North America. Multiple West Indian cultivars exist. The objective of this study was to evaluate the establishment of 13 avocado varieties in the USVI. Thirteen cultivars were sourced from Florida, these cultivars are ‘Brogdon’, ‘Catalina’, ‘Choquette’, ‘Day’, ‘Donnie’, ‘Lula’, ‘Marcus Pumpkin’, ‘Monroe’, ‘Oro Negro’, ‘Pollock’, ‘Russell’, ‘Thompson Red’, and ‘Uh La La’. These grafted cultivars were planted on July 7, 2022, at 5.5 m spacing with drip irrigation installed as a 1 m diameter around the trees. Data on vertical stem growth after planting and the number of lateral shoots was collected monthly. Walk-throughs are conducted biweekly to identify when each cultivar begins flowering. Similarities in vertical stem growth and flowering were observed after 2 years. ‘Day’, ‘Marcus Pumpkin’, ‘Monroe’, ‘Oro Negro’, ‘Russell’, and ‘Thompson Red’ all grew an average of 98 cm. ‘Brogdon’ grew 137 cm which was the most vertical growth of all the cultivars and ‘Catalina’ grew only 43 cm which was the least. By the second year ‘Brogdon’, ‘Catalina’, ‘Oro Negro’, ‘Pollock’, ‘Russell’, and ‘Thompson Red’ all began flowering from January through April with ‘Pollock’ flowering the earliest in January. Avocado cultivars ‘Day’, ‘Russell’, ‘Oro Negro’, ‘Thompson Red’, and ‘Marcus Pumpkin’ have shown similarities in vertical growth over 20 months with only ‘Oro Negro’, ‘Russell’, and ‘Thompson Red’, flowering during the same months.
Speakers
SJ

Samuel Joseph

University of the Virgin Islands
NA
Co-authors
TZ

Thomas Zimmerman

University of the Virgin Islands School of Agriculture
Friday September 27, 2024 11:40am - 11:50am HST
Lehua Suite

12:14pm HST

Postharvest 3 (PH 3)
Friday September 27, 2024 12:14pm - 1:35pm HST
Evaluating the Potential of Gaseous Ozone to Suppress Decay Incidence in Fresh Peaches During Cold Storage - Orestis Giannopoulos
Evaluation of different reflectance models to predict fruit firmness using compression values in sweet cherries cv ‘Skeena’ - Rene Mogollon
Effects of Harvest Regimes on Shelf-life and Quality of Rabbiteye Blueberries - Amit Godara
Facilitating Postharvest Elderberry Fruit Detachment with Ethylene - Steven Sargent
Integrated Analyses of Transcriptomics and Lipidomics Reveal Potential Mechanisms Related to Physiological Disorders of Cold-Stored Hardy Kiwifruit (Actinidia arguta) - Hyowon Park
β-Cyclodextrin Nano-encapsulated Carvacrol Inclusion Complexes Improve Postharvest Quality of Limes - Chang Shu
Nondestructive Detection of Chilling Injury Based on VIS/NIR Spectroscopy in Sweet Potato - Jonghwan Lee
Development and Characterization of Bio-based Nanoparticle Coatings from Sweetpotato Peels - David Picha

Moderator
CS

Chang Shu

USDA-Agricultural Research Service-Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
Friday September 27, 2024 12:14pm - 1:35pm HST
Lehua Suite

12:15pm HST

PH 3 - Evaluating the Potential of Gaseous Ozone to Suppress Decay Incidence in Fresh Peaches During Cold Storage
Friday September 27, 2024 12:15pm - 12:25pm HST
Sanitizing fruit and vegetables with gaseous ozone promotes food safety, marketability, and extended postharvest shelf-life. Ozone is a self-decomposing gas that disinfects and neutralizes microorganisms on packing equipment, water, and produce surfaces. The USDA permits ozone use in "organic" products. Ozone is produced on-site through a corona discharge mechanism using commercially gaseous ozone generators. This study studied gaseous ozone application on peaches, ranging from 0.5 - 5 ppm compared to control storage (CS). Gaseous ozone applications are known for postharvest spoilage vulnerability to assess microbial load reduction and defense against diseases like brown rot and gray mold. Investigated varieties (July Prince, Scarlet Prince, August Lady, and O’Henry), stored under controlled conditions of 35°F (1.7°C) at 90% relative humidity, revealed that 5 ppm ozone resulted in high decay (~40-42%). However, 0.5 ppm treatment maintained peach quality comparable to controls, with decay rates between 3.5 to 7%. Notably, peaches treated with 0.5 ppm also exhibited higher firmness than the other treatments and unaffected visual quality up to the 28th storage day. The findings suggest ozone’s potential to enhance postharvest practices, highlighting its efficiency, and could serve as an effective counteract treatment for decay incidence that will benefit the peach industry.
Speakers
avatar for Orestis Giannopoulos

Orestis Giannopoulos

University of Georgia
Co-authors
AD

Angelos Deltsidis

University of Georgia
CE

Camille Esmel McAvoy

University of Georgia
NA
DC

Dario Chavez

University of Georgia
NA
RC

Ramsey Corn

University of Georgia
Friday September 27, 2024 12:15pm - 12:25pm HST
Lehua Suite

12:25pm HST

PH 3 - Evaluation of different reflectance models to predict fruit firmness using compression values in sweet cherries cv ‘S
Friday September 27, 2024 12:25pm - 12:35pm HST
The compression test is the standard procedure to measure fruit firmness in sweet cherries. Nevertheless, this measurement is not always well correlated with perceived texture by buyers and consumers; therefore, the cherry industry needs a better way to grade fruit firmness. Hyperspectral information was correlated to fruit firmness as an alternative to compression values. ‘Skeena’ cherries, grown under commercial conditions in central Washington, were harvested in 2023 and stored for 30 days at 0-1oC. Compression measurements (at 20oC; FirmTech 2, BioWorks Inc) were carried out at harvest and 15 and 30 days into storage. Immediately after these measurements, hyperspectral images from the fruit (n=1030) were taken using a Vi-NIR camera (Headwall Photonics). The comparison between low (< 303 mm/g), medium (303-374 mm/g), and high firmness (>374 mm/g) groups did not yield any spectral differences. Despite this, iPLS wavelength selection showed bands > 800 nm suitable to model these compression groups. On the other hand, Neural Network, Random Forest, and PLS models were not able to predict compression values (regression) or firmness groups (classification). Furthermore, the regression models tested did not have coefficients of determination higher than 0.42 with root mean squared errors of 40 mm/g for compression values with the training dataset. Classification models achieved total accuracies of around 65-70 % and had problems distinguishing between low-medium and medium-high compression values. All models showed poor performance when tested with an independent data set. These results are in contrast to previous reports, which used a lower fruit number, reinforcing the challenge of tailoring a non-destructive technique to predict firmness through compression values in sweet cherries, a highly variable phenotypic characteristic.
Speakers
RM

Rene Mogollon

Washington State University
Co-authors
CT

Carolina Torres

Washington State University
Friday September 27, 2024 12:25pm - 12:35pm HST
Lehua Suite

12:35pm HST

PH 3 - Effects of Harvest Regimes on Shelf-life and Quality of Rabbiteye Blueberries
Friday September 27, 2024 12:35pm - 12:45pm HST
Blueberry producers in the United States are facing high input costs and labor shortages, which have led them to mechanize several areas of blueberry production, particularly harvesting. Even though the use of machine harvesters is advantageous to producers and new technologies have been developed in recent years, several parts of the process still require improvements. One of the issues caused by the adoption of mechanical harvesting is increased harvest intervals, due to the high capital expenses associated with the purchase of such machinery that in turn leads to limited availability of harvesters to perform the harvest in a timely fashion. This trend may compromise berry quality, particularly in the Southeastern United States. Firmness is a critical factor in determining consumer preference, shelf life, and market value of fresh blueberries. The postharvest quality of blueberries is influenced by various factors, including genotype, postharvest handling, and harvest conditions such as harvest intervals. This study aimed to investigate the impact of different harvest-regimes on fruit quality and storability of ‘Brightwell’ blueberries. The experiment was conducted at the Alma Blueberry Research Farm, with a randomized complete block design. Fruit were hand-harvested at different intervals: T1: every 2 days, T2: every 3 days, and T3: every 7 days. Each treatment was replicated four times, resulting in nine harvests across all treatments. Following the harvest, the berries were sorted for defects, packed in clamshells, and stored at 1°C (34°F) and 85% relative humidity. Fruit quality parameters: firmness, fruit size, color, total soluble solids (TSS), titratable acidity, and fruit rot evaluation were evaluated at four different intervals: 1, 7, 14, and 21 days after harvest. Preliminary results indicate that fruit from the second and third harvests, T1 and T2 exhibited higher firmness readings at harvest compared to T3. Throughout the storage period, the firmness of the fruit was consistently higher in T2 compared to other treatments. A bigger fruit size was obtained at the first harvest of all treatments which declined after 14 days of storage in all three treatments. At the second harvest, T2 had the highest TSS but after 21 days of storage, TSS declined and T1 had the highest TSS after 21 days of storage in all three harvests. Additionally, T3 had a higher fruit rot incidence, and wet, sunken berries in the second and third harvests. So, a harvest interval of less than 7 days is recommended to maintain the fruit quality.
Speakers
AG

Amit Godara

The University of Georgia
Co-authors
AD

Angelos Deltsidis

The University of Georgia
ZR

Zilfina Rubio Ames

The University of Georgia
Friday September 27, 2024 12:35pm - 12:45pm HST
Lehua Suite

12:45pm HST

PH 3 - Facilitating Postharvest Elderberry Fruit Detachment with Ethylene
Friday September 27, 2024 12:45pm - 12:55pm HST
Interest in producing elderberry (Sambucus nigra ssp. canadensis) fruit in North America has increased in recent years, including the subtropical climate of Florida. The fruit contain high amounts of antioxidants in both the juice and solid fractions and are processed into a wide variety of products. Fruit grow in clusters (cymes) of 500 or more fruit (1-2 mm diameter) each, and typically ripen at different rates, depending upon when the flowers were fertilized, the variety/selection and weather conditions. This non-uniform ripening from green to deep purple challenges growers, since unripe fruit must be removed. Delaying cyme harvest until all fruit ripen is not feasible since overripe fruit abscise before unripe fruit ripen. Fruit are typically destemmed from the cymes the day of harvest, either manually or with mechanized systems. Destemming can cause significant loss of salable product as the fruit are often crushed, releasing juice. In a series of tests, we investigated the potential to promote uniform ripening and detachment of elderberry fruit by postharvest exposure to gaseous ethylene, commercially used to initiate ripening in climacteric fruit crops. At a commercial farm in Chiefland, Florida, small segments (approximately 30 fruit each) were cut from cymes with 75% ripe fruit from three elderberry genotypes (DNS11, DNS23 and DNS36). The samples were returned to the UF Postharvest Laboratory that day, divided into two treatment groups ( /- 100 ppm ethylene) and sealed in glass jars (n=3; 3 segments/jar) at 22 °C/95% relative humidity. Jars were opened after 24, 48 and 72 hr to avoid CO2 accumulation; at each timepoint, one jar was removed and fruit examined; remaining jars were resealed and ethylene concentration was reestablished. Exposure to ethylene significantly increased ripe fruit detachment after 24 hr, however partially ripe fruit ripened after 48 hr, irrespective of treatment. Fruit juice content was 46%, pH=5.0. Ethylene did not affect the following parameters, although there were differences in germplasm: soluble solids content (7-14%), total titratable acidity (0.44-0.70%), and total anthocyanin content (8-20 mg · g-1). Attached or detached fruit lost 6-10% weight after 24 hr, whereas stems lost about 50% weight; after 48 hr, shrivel symptoms appeared and weight loss roughly doubled for these same groups. Consideration must be given as to exposure to ethylene for 24 hr for easy fruit removal versus holding for 48 hr for ripening with accompanied higher weight loss and shriveling.
Speakers
SS

Steven Sargent

University of Florida
Professor and Extension Postharvest Specialist
Co-authors
AB

Adrian Berry

University of Florida
NA
AS

Ali Sarkhosh

University of Florida
NA
DJ

David Jarnagin

Hydemoer Co.
NA
KA

Kevin Athearn

University of Florida
NA
Friday September 27, 2024 12:45pm - 12:55pm HST
Lehua Suite

12:55pm HST

PH 3 - Integrated Analyses of Transcriptomics and Lipidomics Reveal Potential Mechanisms Related to Physiological Disorders of
Friday September 27, 2024 12:55pm - 1:05pm HST
Hardy kiwifruit (Actinidia arguta) is highly sensitive to low temperatures, which can cause chilling injury (CI) as a physiological disorder. Peel surface pitting with black/dark brown spots was developed as CI symptoms in cold-stored hardy kiwifruit. In this study, we performed transcriptomic and lipidomic analyses to elucidate the potential mechanism of CI symptoms in cold-stored hardy kiwifruit. The peel tissues of hardy kiwifruit were collected after harvest (HV) and after cold storage; pitted peel tissues from CI-damaged fruit (PT) and healthy peel tissues from CI-unaffected fruit (HT) were also collected. Transcriptomic analysis identified 10,612 differential expressed genes (DEGs) between HV and HT tissues, and 3,206 DEGs were detected between HT and PT tissues. Among the 3,206 DEGs, 1,322 transcripts were up-regulated in HT tissues, while 1,874 transcripts were up-regulated in PT tissues. The KEGG pathway enriched by up-regulated DEGs in HT indicated protein modification, L-valine degradation, and polyol metabolism, while up-regulated DEGs in PT enriched alkaloid biosynthesis, protein modification, and lipid metabolism. In lipidomics analysis, a total of 101 lipids clustered into 14 subgroups were detected in peel tissues of cold-stored hardy kiwifruit. Based on the results of VIP scores (> 1.5), the levels of triacylglycerol (TAG) 54:8, TAG 54:9, phosphatidylcholine (PC) 36:4, PC 34:2, PC 36:5, PC 34:3, and TAG 54:7 were higher in PT tissues, but the levels of phosphatidylethanolamine (PE) 36:2, phosphatidylserine (PS) 38:3, PS 36:0, PC 36:1, PE 34:1, and PE 36:1, were higher in HT tissues, compared with the other tissues. Therefore, the results indicated that the CI symptoms in cold-stored hardy kiwifruit would be derived from integrated transcriptomic and lipidomic results.
Speakers
HP

Hyowon Park

Chung-Ang University
Co-authors
HJ

Hyun Ji Eo

National Institute of Forest Science
NA
JE

Jane E. Stewart

Colorado State University
NA
avatar for Jinwook Lee

Jinwook Lee

Professor, Chung-Ang University
NA
JR

Jorge R. Ibarra Caballero

Colorado State University
NA
UL

Uk Lee

National Institute of Forest Science
NA
Friday September 27, 2024 12:55pm - 1:05pm HST
Lehua Suite

1:05pm HST

PH 3 - β-Cyclodextrin Nano-encapsulated Carvacrol Inclusion Complexes Improve Postharvest Quality of Limes
Friday September 27, 2024 1:05pm - 1:15pm HST
The ripening and senescence of fresh fruit and vegetables are inevitable during storage, transportation, and sale, which will reduce their marketability and cause substantial economic losses. The infection of pathogenic microorganisms can also lead to food safety problems. Plant essential oils are considered a promising strategy to preserve fresh produce. However, their application is limited by several aspects, including high volatility, low solubility, off flavor, etc. Encapsulation technology has emerged as a promising solution to alleviate these limitations. Nanoencapsulation is a delivery system for bioactive compounds that is usually employed to support the stability of the agents, maximize their retention, and control the release of the compounds at the target locations. A nanoemulsion composed of carvacrol and β-cyclodextrin was prepared by an ultrasound-mediated method, and the encapsulation process was conducted using a Buchi® Nano Spray Dryer B-90. The inclusion complex powder was collected and filled to air-permeable sachets. The sachets were then fixed inside commercial clamshells containing limes to simulate shelf-life. Fruit quality and total microbial population were analyzed. The results showed that the dimensions of spray-dried powders were primarily at nanoscale. The encapsulation process did not affect the antimicrobial and antioxidant activities of carvacrol. The nanocapsules prolonged the release of carvacrol. It effectively delayed the rapid color deterioration of limes without causing phytotoxicity, and maintained lime quality with higher firmness and lower weight loss. Free carvacrol and carvacrol/β-cyclodextrin treatments significantly reduced the growth of P. digitatum and total bacteria on fruit peel and inside of the wounds. However, the GC-MS results showed carvacrol residue detected from free carvacrol-treated fruit, but not from the carvacrol/β-cyclodextrin-treated fruit. The results indicate that nano-encapsulated carvacrol/β-cyclodextrin inclusion complexes can be applied as an effective strategy to preserve postharvest produce. Keywords: Nanoencapsulation, nano spray drying, essential oil, postharvest quality, lime
Speakers
CS

Chang Shu

USDA-Agricultural Research Service-Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
Co-authors
XS

Xiuxiu Sun

USDA-Agricultural Research Service-Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
NA
Friday September 27, 2024 1:05pm - 1:15pm HST
Lehua Suite

1:15pm HST

PH 3 - Nondestructive Detection of Chilling Injury Based on VIS/NIR Spectroscopy in Sweet Potato
Friday September 27, 2024 1:15pm - 1:25pm HST
Sweet potato (Ipomoea batatas L.) is one of the seven major food crops grown worldwide. The optimal storage temperature for sweet potatoes is 12-15℃, and chilling injury occur when it falls below 10℃. The initial symptom of chilling injury in sweet potatoes is difficult to discern in visual judgment and requires checking through a cut-off sections. Therefore, this study intended to develop a non-destructive chilling injury prediction model using VIS/NIR spectroscopy sensors. USB4000 Fiber Optical Spectrometer was used for collecting spectrum data in the wavelength of the visible to near-infrared region (400 nm to 1100 nm), and the average value was used by measuring six areas divided into upper, middle, and lower parts to reduce errors. Firmness, total soluble solids, internal chromaticity, chilling index, and Malondialdehyde (MDA) were measured as reference data, and Partial Least Squares Regression(PLSR) method was used for prediction. To increase the accuracy of the model, the near-infrared spectrum data were preprocessed using the Savitzky–Golay 1st and 2nd derivatives (S–G), standard normal variate (SNV), and multiplicative scattering correction (MSC) methods. Excellent performance models for each preprocessing methods were selected, and as a result of verification through the prediction model, the 'Hogammi' variety showed excellent performance in the preprocessing of Savitzky-Golay 2st derivative in TSS and Malondialdehyde (MDA), and CI index showed the best performance in the processing of SNV. As indicators of chilling injury such as the CI index involve subjective opinions of experimenters, the findings of this study could be used as a fundamental step to develop more objective and accurate chilling injury prediction models by including various internal indicators.
Speakers
JL

jonghwan lee

kangwon national university
Co-authors
CJ

CheonSoon Jeong

kangwon national university
NA
HC

HanRyul Choi

National Institute of Horticultural and Herbal Science
NA
MB

MinWoo Baek

kangwon national university
NA
SJ

SeMin Jang

kangwon national university
NA
ST

Shimeles Tilahun

kangwon national university, jimma university
NA
ST

SuHo Tae

kangwon national university
NA
Friday September 27, 2024 1:15pm - 1:25pm HST
Lehua Suite

1:25pm HST

PH 3 - Development and Characterization of Bio-based Nanoparticle Coatings from Sweetpotato Peels
Friday September 27, 2024 1:25pm - 1:35pm HST
Bio-based nanoparticle coatings were developed using nanomaterials extracted from sweetpotato peels and combined with other biopolymers to reduce postharvest deterioration of sweetpotato roots and other fresh produce items. The sustainable coating materials applied as thin films to the surface of washed sweetpotato roots reduced postharvest deterioration, weight loss, and respiration rate, while maintaining root market quality. Chemical and physical characterization was made of the cellulose nanomaterials (CNMs), pectin, and phenolic compounds from ‘Beauregard’ sweet potato peel tissue. The peel contained 40.2% cellulose, 19.1 % lignin, 10.8% hemicellulose and 29.8% pectin. The extracted CNMs from the peel tissue showed a high degree of crystallinity, particularly for cellulose nanocrystals. The CNMs and pectin fractions formed stable water dispersions with strong shear thinning behavior suitable for coating application. The thin films formed by the CNMs and pectin fractions exhibited an entangled fiber network structure with significantly reduced water and gas permeability. Our results demonstrated the feasibility of using sweetpotato peel tissue as an integral component in a bio-based nanoparticle film coating.
Speakers
DP

David Picha

Louisiana State University Agricultural Center
Co-authors
QW

Qinglin Wu

LSU Agricultural Center
NA
RA

Ragab Abouzeid

School of Plant, Environmental and Soil Sciences
NA
Friday September 27, 2024 1:25pm - 1:35pm HST
Lehua Suite

1:59pm HST

2:00pm HST

PNM 3 - Optimizing Nitrogen Fertilization for Evergreen Blueberry (Vaccinium corymbosum interspecific hybrids) in Florida
Friday September 27, 2024 2:00pm - 2:15pm HST
There are multiple ways to grow highbush blueberries (Vaccinium corymbosum interspecific hybrids). In Florida, an evergreen growing system was developed to overcome unpredictable chill hour accumulation. In this system, blueberry bushes retain their leaves throughout the year when fertilized appropriately. Deciduous blueberry farms typically skip fertilization during the fall and winter months. On the other hand, evergreen blueberry farms require winter fertilization to ensure healthy foliage. Therefore, fertilizer recommendations for deciduous blueberry are not applicable to evergreen blueberry. This research aims to optimize nitrogen fertilization for evergreen southern highbush blueberry plants in Florida. ‘Arcadia’ and ‘Sentinel’ southern highbush blueberry plants were grown in a high tunnel in Citra, FL. Plants were fertigated according to commercial practices, except for nitrogen (N). Nitrogen was applied manually as ammonium sulfate at 5 different annual rates (in Kg/ha): 5.6, 83.4, 138.9, 222.3, and 444.6. Plant size, leaf area index, leaf N concentration, fruit yield, and fruit quality were measured during the 2023 and 2024 seasons. Nitrogen fertilization rates affected plant growth during the spring and summer, but not during the fall and winter. Higher N fertilization rates led to higher leaf area index, a proxy for leaf retention. Plants in the lowest N fertilization treatment were not evergreen, as they dropped nearly all their leaves in the winter. Leaf N concentrations of plants in treatments 83.4 Kg/ha or higher were above the reference levels for N deficiency. Linear plateau regressions were used to identify optimum fertilization rates. During the 2023 season, ‘Arcadia’ exhibited a yield plateau, but ‘Sentinel’ did not, suggesting that N fertilization has cultivar-specific effects. All fruit harvested exhibited commercial quality in terms of soluble solids. However, fruit in the lowest fertilization rate was softer and more acidic than fruit in all other treatments. These results suggest that multi-year studies with multiple varieties are necessary to identify N fertilization rates that maximize agricultural productivity while minimizing fertilizer inputs.
Speakers
GN

Gerardo Nunez

University of Florida
Co-authors
LG

Lauren Goldsby

University of Florida
NA
Friday September 27, 2024 2:00pm - 2:15pm HST
Lehua Suite

2:15pm HST

PNM 3 -The Effects of Nutrient Management on Yield in Cut-and-Come-Again Kale Production.
Friday September 27, 2024 2:15pm - 2:30pm HST
Cut-and-come-again, or repeat harvesting, is a practice in which a single planting of greens is harvested on multiple occasions. This is a common practice among small-scale, urban, and home producers in which the outermost leaves are removed, leaving the growing center of the plant intact enabling multiple harvests without compromising plant health. As this practice is not common among large-scale and commercial producers, there are currently no research-based fertilizer recommendations for cut-and-come-again greens. General guidance simply suggests continued, nitrogen-heavy fertilizer applications to ensure repeated harvests. This type of guidance is not easy to follow for beginners or for growers looking to improve their cut-and-come-again yields. An experiment was designed to examine eight different fertilizer application strategies to determine which provided better growth and nutritional quality in later kale harvests while limiting nutrient leaching. Fertilizer applications for the cut-and-come-again treatments (CC) ranged from an initial fertilizer application matching local nutrient recommendations, to repeated applications either the initial complete application or a nitrogen side dressing at every third, every other, or at each harvest. A single harvest control (ODB) was also harvested at the baby stage at each CC harvest. At each harvest, total and marketable yield were measured and crop quality for marketability was assessed per the USDA guidelines for kale and greens. There were more issues with slow growth, slow regrowth, and missing harvests for pots in the fall than the spring, and more issues in 2023 than in 2022. Some issues were directly related to significant caterpillar damage in the fall of 2023 which also affected the marketability of the leaves harvested. The expected dose response to fertilizer treatment was not observed in any growing season of the two years of the study completed so far. While some differences in yield between treatments were observed, these were predominantly between the ODB control and CC treatments, but not among CC treatments. The expected drop in yield with successive harvests was also not consistently observed in CC treatments. The CC treatment receiving only the initial fertilizer application exhibited a drop in yield with successive harvests in only two of the four growing seasons. Further examination of the fate of nutrients in the leaf material, soil and leachate from the experiment should explain these unexpected results and provide more clarity on an optimal fertilizer treatment.
Speakers
LW

Leigh Whittinghill

The Connecticut Agricultural Expeirment Station
Friday September 27, 2024 2:15pm - 2:30pm HST
Lehua Suite

2:30pm HST

PNM 3 - Growth Responses of Hydroponic Vegetable Transplants to Nutrient Solution Concentrations Made with Food Waste Liquid Ana
Friday September 27, 2024 2:30pm - 2:45pm HST
Food waste liquid anaerobic digestates (FWLAD) have received much public attention for its potential as an organic fertilizer source as they are rich in mineral elements. However, FWLAD can contain high salinity and high NH4 concentration, and thus, the optimum application rates need to be determined to deliver required plant nutrients without excessive salt and NH4 level. The objective of this study was to evaluate the effects of nutrient solution concentration made from FWLAD on the growth of leafy vegetable seedlings. The seeds of lettuce (Lactuca sativa) ‘Rex’, ‘Muir’, and ‘Roxy’, Swiss chard (Beta vulgaris subsp. vulgaris) ‘Rhubarb’, bok choy (Brassica rapa subsp. chinensis) ‘Mei Qing Choi’, and kale (Brassica oleracea var. sabellica) ‘White Russian’ were sown in rockwool plug and grown at 22 °C under sole-source LED lighting with an 18-h photoperiod at a photosynthetic photon flux density of 200 µmol∙m-2∙s-1. After germination, the seedlings were sub-irrigated with nutrient solution made with either crude or processed FWLAD at electrical conductivities (ECs) of 1, 2, 3, or 4 dS·m–1. Four weeks after treatment, when using crude FWLAD, shoot fresh mass of three lettuce cultivars decreased by 76-92% as EC increased from 1 to 4 dS·m–1. In contrast, with processed FWLAD, lettuce ‘Adriana’ and ‘Roxy’ showed 68-1080% greater shoot fresh mass at an EC of 2 dS·m–1 compared to an ECs of 1, 3, or 4 dS·m–1. Shoot fresh mass of lettuce ‘Muir’ at an EC of 2 dS·m–1 was similar with that at an EC of 1 dS·m–1 but 380-516% greater than those at ECs of 3 or 4 dS·m–1. In lettuce, the EC of FWLAD had similar effects on leaf area as it did on shoot fresh mass, but it had minimal effects on leaf number, relative chlorophyll concentration, and shoot dry mass. In kale, Swiss chard, and bok choy, the EC of FWLAD had little effects on plant growth attributes. Our results suggest that leafy vegetable seedlings vary in their responses to nutrient solution concentrations derived from FWLAD, with lettuce exhibiting greater sensitivity than Swiss chard, bok choy, and kale. In lettuce, lower concentrations of FWLAD (at an EC ≤2 dS·m–1) increased shoot fresh mass.
Speakers
EW

Emily Webb

Arizona State University
NA
Co-authors
YP

Yujin Park

Arizona State University
ZC

Zhihao Chen

Arizona State University
NA
Friday September 27, 2024 2:30pm - 2:45pm HST
Lehua Suite

2:45pm HST

PNM 3 - Foliar Boron Nutrition in Grafted Watermelon: Impact on Fruit Development, Yield, and Quality
Friday September 27, 2024 2:45pm - 3:00pm HST
Grafting is an effective management strategy in watermelon crop against soil borne pathogens. Carolina strongback (SB) rootstock used for grafting, is resistant to both fusarium wilt and root knot nematodes which are devastating soil borne pests of watermelon. However, recent trials have shown that SB grafted plant bear fruits 7-10 days later than regulate plants leading to farmers losing early market which is more profitable. Further, tissue boron content in SB grafted plants were reported to be lower than regular watermelon nursery plants. Boron is the key micro-nutrient involves in cell wall and cell membrane, pollination, pollen germination, cell division, translocation of carbohydrates and fruit development. We hypothesize that foliar application of boron will cure the boron deficiency in grafted plants and leads to early fruit set similar to regular watermelon nursery. To test this hypothesis, a field experiment was conducted at Edisto Research and Education Centre, SC with the objective to evaluate the impact of foliar boron applications on pollen viability, pollination, fruit set, and periodic fruit yield as compared to regular watermelon nursery. The experiment was comprised of four treatments including a regular watermelon nursery control, in randomized complete block design. The soils had medium to low boron content of 0.1 pounds/acre. The soils were medium in potassium (133 pounds/acre), zinc (5.2 pounds/acre) and manganese (13 pounds/acre). Within first 25 days of transplanting, we did not observe any difference in the watermelon aboveground growth and biomass accumulation, in different treatments. Further, we will evaluate the impact of foliar boron application on pollen viability, pollination, watermelon fruit set, fruit yield and quality in SB grafted nursery.
Speakers
BJ

Bhupinder Jatana

Clemson University
Co-authors
TS

Tom Sanders III

Clemson University
NA
Friday September 27, 2024 2:45pm - 3:00pm HST
Lehua Suite

3:00pm HST

PNM 3 - Optimization of Tissue Culture Medium for Enhanced Proliferation of Little-Leaf Mockorange (Philadelphus microphyllus A.
Friday September 27, 2024 3:00pm - 3:15pm HST
Native plants play a crucial role in landscape ecosystems due to their adaptability, yet propagating certain species through traditional methods can pose challenges. Tissue culture emerges as a promising alternative for efficient propagation, demanding an optimized culture medium for desirable proliferation. Efficient proliferation of newly introduced plant species in tissue culture often necessitates meticulous experimentation with varying salt compositions to optimize mineral concentrations and growth regulator levels within the culture medium. This study aimed to employ Response Surface Methods (RSM) to assess the effects of different mineral combinations, including nitrogen (N), calcium (Ca), potassium (K), and phosphorus (P), along with a cytokinin (zeatin), on the shoot proliferation and growth of little-leaf mockorange in tissue culture. Forty-six treatment combinations were designed, with zeatin concentrations of 0.82, 1.095, or 1.37 µM, and varying levels of N (22.5, 30, or 37.5 mM), Ca (1.125, 1.5, or 1.88 mM), P (0.31, 0.625, or 0.94 mM), and K (5, 10, or 15 mM). These treatments were evaluated for their impact on axillary shoot formation, shoot length, and shoot dry weight. Response surface analyses revealed optimal concentrations of N (32.5 to 35 mM), Ca (1.5 mM), and P (0.625 mM), while the influence of potassium on responses was found to be nonsignificant in the regression models, hence, K concentrations were limited to linear trends in the analysis. Notably, medium supplemented with 1.1 µM zeatin demonstrated a significant positive impact on shoot proliferation. The RSM model demonstrated the feasibility of determining optimal concentrations of zeatin, N, Ca, and P in a single experiment, facilitating the in vitro growth of little-leaf mockorange shoots. This study underscores the efficacy of RSM in tissue culture experiments, offering a time- and cost-effective alternative to conducting multiple separate experiments and providing valuable insights into medium optimization. Such findings contribute to the advancement of tissue culture techniques, particularly in propagating native plant species critical for landscape sustainability.
Speakers
avatar for Razieh Khajehyar

Razieh Khajehyar

Scientist, University of Idaho, Germains Seed Technology, Inc.
Co-authors
RT

Robert Tripepi

University of Idaho
NA
SL

Stephen Love

University of Idaho
NA
WJ

William J. Price

University of Idaho
NA
Friday September 27, 2024 3:00pm - 3:15pm HST
Lehua Suite

3:15pm HST

PNM 3 - Nano NPK and Salicylic Acid Chemigation in Processing Tomato Production: Impact on Efficiency and Sustainability
Friday September 27, 2024 3:15pm - 3:30pm HST
Chemical fertilizers are key to enhancing tomato productivity, yet their excessive or imbalanced use can lead to higher costs, energy inefficiency, and negative environmental impacts. Recent advancements in nano fertilization seek to optimize nutrient use, minimize losses, and improve farm economics and environmental sustainability. Additionally, salicylic acid (SA) as a chemical inducer has shown potential to boost crop yields by enhancing stress tolerance in plants. Our research evaluated the effects of various rates of nano NPK fertilization combined with SA chemigation on the efficiency and sustainability of processing tomatoes (Solanum Lycopersicum L., cv. BHN 685) production in a drip-irrigated plasticulture system. Conducted over the 2022 and 2023 growing seasons, this two-factorial experiment tested nano NPK rates (0, 40, 80, 120 kg/ha) and SA levels (0 vs. 0.3%), using conventional NPK fertilizers as the control. The results showed that tomato yields were significantly influenced by SA chemigation, nano NPK fertilization, and the growing year, without interactive effects between and among these factors. SA chemigation with 120 kg NPK/ha increased yields by 9% compared to the control. Yields were similar between the 120 kg/ha SA chemigation and 120 kg/ha nano NPK treatments but were significantly higher (by 21%) under the 120 kg nano NPK with SA chemigation, suggesting effective synergy between SA and nano fertilization. SA chemigation and NPK fertilization reduced cull fruit yields, with nano NPK showing the most substantial reduction. Production costs were slightly higher for the combination of SA chemigation and nano NPK ($7,114/ha), but profitability was significantly increased, peaking at $2,487/ha in this treatment. Energy use efficiency also increased from 42.3% in the control (120 kg NPK/ha) to 51.1% with the combined treatment (120 kg nano NPK/ha with SA chemigation), and specific energy use per unit of tomato was decreased from 1.9 MJ/kg to 1.6 MJ/kg. Greenhouse gas emissions per ton of tomato were reduced from 46.3 kg CO2 equivalent/ha in the control to 42.7 kg/ha with combined nano NPK and SA chemigation. In conclusion, nano NPK fertilization coupled with SA chemigation proves to be an effective strategy for enhancing the efficiency and sustainability of processing tomato production, improving yield, profitability, and environmental outcomes.
Speakers
TH

Thomas Harker

Research Assosiate, The Ohio State University
Thomas Harker currently holds a research associate position specializing in horticultural and specialty crops at the Ohio State University South Centers. With an extensive career spanning over 25 years, he has been deeply immersed in the exploration and enhancement of various crops... Read More →
Co-authors
AR

Arifur Rahman

The Ohio State University South Centers
NA
BB

Brad Bergefurd

Brandt Discovery
NA
EB

Ed Brown

The Ohio State University Extension Athens County
NA
RI

Rafiq Islam

The Ohio State University South Centers
NA
WL

Wayne Lewis

The Ohio State University South Centers
NA
ZG

Zhenhao Guan

The Ohio State University South Centers
NA
Friday September 27, 2024 3:15pm - 3:30pm HST
Lehua Suite

3:30pm HST

PNM 3 - Nano NPK and Salicylic Acid Chemigation on Tomato Phytochemicals and Fruit Quality
Friday September 27, 2024 3:30pm - 3:45pm HST
Tomato stands out as a premier high-value specialty crop globally. However, the inefficiency of conventional fertilizers in nutrient utilization necessitates excessive fertilization to maintain tomato yields, which adversely impacts fruit quality. Nanotechnology, aimed at precise nutrient management to enhance efficiency and economic viability in farming, is gaining attention in agriculture. Similarly, salicylic acid (SA) has emerged as a potential chemical inducer to enhance plant metabolic activities, stress tolerance, and crop yield in the face of climate change. Our two-year field study aimed to assess the impact of varying rates of nano NPK fertilization and SA chemigation on the phytochemical properties, nutritional quality, and fruit attributes of processing tomatoes (Solanum Lycopersicum L., cv. BHN685), relative to conventional fertilization. Employing a two-factorial drip-irrigated plasticulture setup in a completely randomized design, we tested four levels of nano NPK (0, 40, 80, and 120 kg/ha) and two levels of SA (0 vs. 0.3%), each replicated four times. Results showed that tomato fruits subjected to SA chemigation with nano-NPK fertilization exhibited a significant increase in concentration of phytochemicals. Notably, vitamin-A, vitamin-C, lycopene, β-carotene, polyphenol, flavonoid, anthocyanin, and antioxidant capacity displayed substantial increases ranging from 2.5% to 51.2% compared to the control. Particularly noteworthy were the remarkable enhancements in flavonoid and anthocyanin concentrations, registering at 50% and 51.2%, respectively. Conversely, application of nano NPK alone led to discernible increases solely in flavonoid and anthocyanin concentrations, accompanied by decreases in other phytochemicals. Further analysis underscored the synergistic benefits of SA and nano-NPK, resulting in superior color, taste, and phytochemical richness of tomato fruits. K-means cluster analysis corroborated the efficacy of the SA with nano NPK (120 kg/ha) treatment in eliciting optimal fruit characteristics. Moreover, quality assessment revealed the superiority of the SA nano-NPK (120 kg/ha) treatment, with a quality index of 0.61 compared to the control's 0.47, indicative of its superior attributes. Additionally, the nutritional quality index demonstrated a gradual increase in nutrient enrichment across treatments, with the SA and nano NPK (120 kg/ha) combination yielding the highest score. In conclusion, our study highlights the pivotal role of SA in conjunction with nano NPK (120 kg/ha) in enhancing tomato phytochemical content and overall fruit quality. These findings bear significant implications for optimizing horticultural practices and promoting sustainable food production endeavors.
Speakers
TH

Thomas Harker

Research Assosiate, The Ohio State University
Thomas Harker currently holds a research associate position specializing in horticultural and specialty crops at the Ohio State University South Centers. With an extensive career spanning over 25 years, he has been deeply immersed in the exploration and enhancement of various crops... Read More →
Co-authors
AR

Arifur Rahman

The Ohio State University South Centers
NA
BB

Brad Bergefurd

Brandt Discovery
NA
EB

Ed Brown

The Ohio State University Extension Athens County
NA
RI

Rafiq Islam

The Ohio State University South Centers
NA
WL

Wayne Lewis

The Ohio State University South Centers
NA
ZG

Zhenhao Guan

The Ohio State University South Centers
NA
Friday September 27, 2024 3:30pm - 3:45pm HST
Lehua Suite

3:45pm HST

PNM 3 - Alternative Fertilizer Methods For Palm Trees
Friday September 27, 2024 3:45pm - 4:00pm HST
Lack of water holding and cation exchange capacity severely limit fertilizer application methods for new palm tree transplants in sandy soils in S. Florida. Typically, palm trees are fertilized using an 8-2-12 4 granular fertilizer but with little rooting to enhance fertilizer capture and no soil solution to improve nutrient uptake, establishment may be slow. Alternative fertilizers, including palm tree injection, were evaluated to determine the best method to improve palm tree establishment under these conditions. A research trial was conducted using Christmas Palms (Adonidia merrillii) that were established on sandy soils with less than 2% organic matter. After planting, palms were not fertilized for six months. Palm trees were treated with the following fertilizers: 1) 8-2-12 4 (PS), 2) 0-0-22 4(KM) 3) PHOSPHO-jet PALM-jet injection (PJ) 4) PHOSPHO-jet PALM-jet apical meristem drench (AM) and 6) “Gator Grip” (GG) fertilizer pouch directed at the apical meristem. Visual quality and drone imagery were used to assess palm health. Volumetric water content (VWC) was determined at three different depths and root growth was captured using a mini-rhizotron. Six months after the initial treatment application, treatment differences were not visually apparent and VWC was below 10% for the majority of measurements captured at all depths. Rooting data at this stage was minimal. Palm trees may grow very slowly and under these environmental conditions, it may take the palm over a year to replace an entire crown. Therefore, yearly updates will be presented for this three-year trial to best determine which treatment provides the best solution to establish transplanted palms in the landscape and maintain palm health.
Speakers
MM

mica mcmillan

University of Florida
Co-authors
KW

Karen Williams

University of Florida
NA
NF

Naomi Franklin

University of Florida
NA
Friday September 27, 2024 3:45pm - 4:00pm HST
Lehua Suite
 


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