ASHS 2025 Conference: Full Schedule

9:00am CDT

PBIG 1 - Testing RITA® Temporary Immersion Bioreactor System For Germination Of Cornus florida Somatic Embryos

Tuesday July 29, 2025 9:00am - 9:15am CDT

Powdery mildew, caused by the fungus Erysiphe pulchra, is one of the most serious diseases affecting the popular ornamental tree flowering dogwood (Cornus florida). Employing gene editing techniques such as CRISPR to introduce powdery mildew resistance by inactivating the Mildew Locus O (MLO) gene requires an efficient genetic transformation system. This novel research will fill a critical gap in our knowledge of flowering dogwood biotechnology. Previous research efforts have genetically transformed embryogenic dogwood cultures, now we are aiming to produce transgenic plantlets. Recent research focused on using the RITA® temporary immersion bioreactor system for testing germination of somatic embryos and conversion to plants. The primary test was the impact of the plant growth regulator (PGR) gibberellic acid (GA3). For this experiment, we analyzed the impact of different environmental light exposures on dogwood embryo stress levels by observing anthocyanin production. The starting material was unwashed callus transformed with the GUS reporter gene and subjected to one of three RITA® treatments to examine the influence of varying light levels. Treatments included full darkness, continuous low light, and a combination of both light conditions for different durations of time. Few somatic embryos germinated from the treatment with 60 days of full darkness, but the anthocyanin stress was absent. We observed the same result for constant low light exposure except for exponential growth of the transgenic callus. The treatment in which the somatic embryos were in full darkness for 30 days and switched to low light for another 30 days showed a higher germination rate, but there were increased signs of anthocyanin stress. Implementation of this research will assist in the optimization of the production of plantlets from dogwood cultures transformed with a CRISPR-Cas9 construct that can inactivate the MLO gene to obtain powdery mildew resistance.

Speakers

Heather Gladfelter

University of Georgia

Co-authors

Dayton Wilde

University of Georgia

Julianne Patterson

University of Georgia

Tuesday July 29, 2025 9:00am - 9:15am CDT
Strand 11A

Oral presentation, Plant Biotechnology 1

Subject Plant Biotechnology
Poster # csv
Funding Source University of Georgia Horticulture Department

9:15am CDT

PBIG 1 - FreshID: Machine Learning for Fruits and Vegetables Quality Evaluation

Tuesday July 29, 2025 9:15am - 9:30am CDT

Strand 11A

Fresh fruits and vegetables are invaluable for human health, but their quality deteriorates before reaching consumers during distribution due to ongoing biochemical processes and compositional changes. The current lack of any objective indices for defining “freshness” of fruits or vegetables limits our capacity to control product quality and leads to food loss and waste. In this work, we undertook interdisciplinary research to address plant science challenges related to food security and human health. This work has leveraged machine learning technologies and multi-omics tools to understand post-harvest senescence and microbial spoilage of fresh produce for the purpose of developing a simple imaging “FreshID” device to evaluate fruit and vegetable quality. In essence, we are proposing a comprehensive research program to identify proteins and compounds as “freshness-indicators” and to aid development of an innovative and easy-to-use accessibility tool to accurately estimate the freshness and/or contamination of produce. The goal of the proposed research will be advances in both basic research and applied science. Such a tool would allow a new level of post-harvest logistics, supporting availability of high-quality, nutritious, fresh produce.

Speakers

Tie Liu

University of Florida

Tuesday July 29, 2025 9:15am - 9:30am CDT
Strand 11A

Oral presentation, Plant Biotechnology 1

Subject Plant Biotechnology
Poster # csv
Funding Source NIFA

9:30am CDT

PBIG 1 - Bioinformatics-Assisted Identification of Novel Plant Promoter Motifs

Tuesday July 29, 2025 9:30am - 9:45am CDT

Strand 11A

Plant natural promoters are always very long and contain many different promoter motifs, providing complex expression patterns, while synthetic promoters can be constructed to be very short in sequence and very strong in promoter strength. Bioinformatics-assisted de novo promoter motif discovery searches for statistically overrepresented motifs without the inclusion of biological information, leading to limited prediction efficiency. To overcome this limitation, we have developed a novel ensemble approach by mapping the motifs detected by a set of selected bioinformatics tools back to the promoter sequences and looking for overlapping motif regions among the detected motifs. Using this approach, we searched and identified novel constitutive promoter motifs from the soybean genome. Seven user-friendly bioinformatics tools, including BioProspector, CisGenome, HOMER, MEME, MotifSuite, RSAT Plants, and Weeder were employed for the de novo discovery of constitutive motifs among 11 published soybean constitutive promoters. A total of 62 promoter motifs were detected among the 11 soybean constitutive promoters by at least four of the seven bioinformatics tools. A tetramer (4×) of each promoter motif was cloned in front of the minimal 35S promoter driving GUS reporter gene expression, and used for tobacco leaf agroinfiltration and stable Arabidopsis transformation. Quantitative GUS activity assays following transient tobacco leaf agroinfiltration identified 26 of the 62 promoter motifs that drove GUS expression significantly higher than the basal level conferred by the minimal 35S promoter. Histochemical GUS analysis of stable transgenic Arabidopsis seedlings found that 16 of the 26 promoter motifs were 19 ~ 60 bp in length and exhibited constitutive expression with variable promoter strength, and 7 of the 26 promoter motifs showed strong constitutive expression which was comparable to (slightly weaker than) the 35S promoter. Thus, these novel constitutive motifs can be used to drive constitutive gene expression in dicot species.

Speakers

Wusheng Liu

North Carolina State University

Co-authors

debao huang

NCSU

Emily Brooks

North Carolina State University

Tuesday July 29, 2025 9:30am - 9:45am CDT
Strand 11A

Oral presentation, Plant Biotechnology 1

Subject Plant Biotechnology
Poster # csv
Funding Source BASF

9:45am CDT

PBIG 1 - Declining Nitrogen Availability Increases Sink Strength and Storage Root Formation in Sweetpotato cv. ‘Beauregard’

Tuesday July 29, 2025 9:45am - 10:00am CDT

Strand 11A

In sweetpotato (Ipomoea batatas L.), the sink strength of developing adventitious roots limits storage root formation. Sucrose synthase (SuSy) has been identified as a marker for sink strength in developing storage roots. In model systems, declining nitrogen (N) availability has been associated with increased carbohydrate allocation to root systems. To test the hypothesis that N limitation triggers increased SuSy activity that leads to storage root formation, we subjected sweetpotato cv. ‘Beauregard’ to progressively declining N treatments in a split-root system. SuSy expression and root system architecture were evaluated over 15 days, and storage root formation was assessed at 50 days. Declining N availability enhanced SuSy activity in the root base tissue across all time points and was associated with increased lateral root count at 15 days. Previous work has shown that the anatomical cue of the onset of storage root formation, the appearance of anomalous cambia, is initially limited to the root base tissue. The omission of N was associated with decreased root base SuSy activity and an overall reduction in root architectural attributes. These data support the hypothesis that declining N could be a critical switch for storage root formation in sweetpotato. Our findings have profound implications for increasing N fertilizer efficiency and enhancing our understanding of the intrinsic and environmental variables that mediate storage root formation and productivity in this globally important crop.

Speakers

Marissa Barbosa

Lousiana State University

Co-authors

Arthur Villordon

LSU Agcenter

Don La Bonte

Louisiana State Univ

Lisa Arce

Louisiana State University

Mae Ann Bravo

Louisiana State University

Tuesday July 29, 2025 9:45am - 10:00am CDT
Strand 11A

Oral presentation, Plant Biotechnology 1

Subject Plant Biotechnology
Poster # csv
Funding Source US-Israel Agricultural Research Development Fund

1:29pm CDT

O/LT - Oral Session

Tuesday July 29, 2025 1:29pm - 1:30pm CDT

Strand 11A

Speakers

Alexis Suero

North Carolina State University

Tuesday July 29, 2025 1:29pm - 1:30pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

1:30pm CDT

O/LT - Integrating Polarization Imaging into Turfgrass Phenotyping for Enhanced Drought Stress Assessment

Tuesday July 29, 2025 1:30pm - 1:45pm CDT

Strand 11A

Investigating novel sensing solutions is important for improving the existing phenotyping pipeline. Polarization is strongly correlated with the geometric properties of an object, such as surface roughness and its orientation relative to the sensor or light source. It has the potential to detect leaf wilting and quantify leaf angles in turfgrass, which are both crucial in precision turfgrass irrigation and crop coefficient determination. This study explores the integration of polarization imaging into RGB imaging pipelines for evaluating turfgrass responses to drought. A controlled dry-down was conducted on two zoysiagrass cultivars and two bermudagrass cultivars grown in pots. Polarization images, RGB images, and visual wilting ratings were collected daily during the four-day dry-down period. Leaf angles, both azimuth and zenith, were derived from top- and side-view RGB images, respectively. We analyzed polarization metrics, including the degree of linear polarization (DoLP) and the angle of polarization (AoP), to assess their relationship with drought stress indicators, such as wilting scores, low Excess Green Index (EGI) values, and changes in leaf angles. EGI and the standard deviation of AoP strongly correlated with wilting scores. Furthermore, DoLP values correlated with leaf zenith angle when the incident light angle was known.

Speakers

Alexis Suero

North Carolina State University

Co-authors

Jerome Maleski

North Carolina State University

Jing Zhang

North Carolina State University

Michael Kudenov

North Carolina State University

Tuesday July 29, 2025 1:30pm - 1:45pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf

1:45pm CDT

O/LT - Responses of Landscape Plants under Deficit Irrigation

Tuesday July 29, 2025 1:45pm - 2:00pm CDT

Strand 11A

Ornamental plants are essential components of both rural and urban landscapes, with the horticultural industry generating $2.01 billion in bedding and garden plant sales in 2019. However, increasing drought stress, affecting 99.3% of Utah in 2023, highlights the need for water-efficient landscaping. Water-wise landscaping offers a promising solution by conserving water while maintaining visual appeal, making it increasingly popular in arid and semi-arid regions. This study was to investigate the effects of deficit irrigation frequency on the morphological and physiological of 13 landscape plant taxa: Caryopteris ×clandonensis ‘Blauer Splatz’ (Sapphire SurfTM bluebeard), Cercis canadensis (eastern redbud), Cercis occidentalis (western redbud), Cotoneaster ×suesicusn ‘OSUCOT2’ (Emerald BeautyTM cotoneaster), Hesperaloe parviflora ‘Straight Up Red’ (‘Straight Up Red’ Texas red yucca), Miscanthus sinensis ‘NCMS2B’ (bandwidth maiden grass), Penstemon barbatus ‘Novapenblu’ (Rock CandyTM blue penstemon), Penstemon pinifolius (pineleaf beardtongue), Penstemon strictus (rocky mountain beardtongue), Physocarpus opulifolius ‘Diabolo’ (‘Diabolo’ ninebark), Physocarpus opulifolius ‘Little Devil’ (Little DevilTM ninebark), Rosa ×hybrida ‘Meifranjin’ (Blushing Drift® rose), and Vitex agnus-castus ×rotundifolia ‘Helen Froehlich’ (Summertime BluesTM vitex). The experiment was conducted at the Utah Agricultural Experiment Station’s Greenville Research Farm in North Logan, UT, from 1 Jun to 31 Oct 2024. Eight plants per species were randomly assigned to one of three irrigation frequencies based on reference evapotranspiration (ETo): high (80% ETo), moderate (50% ETo), and low (20% ETo). Overall plant appearance was evaluated biweekly using a visual rating scale from 0 (dead) to 5 (excellent). Plant growth, stomatal conductance, and canopy temperature were recorded monthly. Net photosynthetic rate, transpiration rate, and vapor pressure deficit were measured in August and September. Results indicate species-specific responses to deficit irrigation. Some species, such as P. barbatus and P. strictus, exhibited improved visual quality, lower canopy temperatures, and higher photosynthetic rates under more frequent irrigation. In contrast, other species were not affected by reduced irrigation frequency.

Speakers

Zirui Wang

Utah State University

Co-authors

Darren Haver

University Of California Cooperative Extension

Jared Sisneroz

UC Davis

Lloyd Nackley

oregon state university

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

Lorence Oki

University Of California, Davis

Natalie Levy

University Of California Cooperative Extension

Ryan Contreras

Oregon State University

Soohyung Kim

University of Washington

Ursula Schuch

University of Arizona

Youping Sun

Utah State University

Tuesday July 29, 2025 1:45pm - 2:00pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf

2:00pm CDT

O/LT - A Tale of Three City Parks

Tuesday July 29, 2025 2:00pm - 2:15pm CDT

Strand 11A

Horticulturists and landscape managers are often highly skilled professionals with an extensive understanding of plant biology and growth requirements. However, despite this knowledge, the post-construction soil conditions in which new landscapes are often installed can undermine the success of plantings. In the best-case scenario, horticulturists with passion and perseverance provide attentive management to the plants to help establish the landscape, but this process can often require a deep dive into soil science, an area that many horticulturists may not be equipped to handle fully. The issue of urban soil is gaining increased attention from soil scientists, but a greater integration of horticulture and urban soil science is essential. Similarly to how soil science and crop science are often interwoven, a more holistic approach is needed to bridge the gap between plant knowledge and urban soil conditions. This would better equip horticulturists and landscape professionals to manage the complexities of urban environments. A notable example of this challenge can be found in downtown Oklahoma City, where three large public gardens have been developed within a one-mile span. Each garden presents its own set of unique challenges, including varying soil types, management timelines, and irrigation sources. Myriad Gardens, established in 1970’s has soil that has been disturbed and modified since the early 1900’s. With a complete garden renovation in 2012, Myriad has an average soil pH range of 6.7-7.7. Upper Scissortail previously, an industrial neighborhood was established in 2019 and constructed utilizing seven different soil formulas. With 1000 newly planted trees, poor quality well irrigation water, and a soil pH over 8.0, plant establishing has been challenging for the staff. Finally, Lower Scissortail built in 2022 was also developed with five soil formulas and like Myriad is on city water that has shown to be a better source of water. This case study highlights the complexity of managing urban landscapes and underscores the importance of addressing soil issues at the onset. For horticulturists, it is no longer enough to possess plant knowledge alone. They must also understand the intricate soil dynamics that can make or break the success of a landscape.

Speakers

Casey Hentges

Oklahoma State University

Co-authors

Justin Quetone Moss

Oklahoma State University

Tuesday July 29, 2025 2:00pm - 2:15pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf

2:15pm CDT

O/LT - Thriving in Bloom: Opportunities and Challenges for Flower Growers in the Northeastern United States

Tuesday July 29, 2025 2:15pm - 2:30pm CDT

Strand 11A

Flower production in the Northeastern United States is experiencing a revival as consumer demand for locally grown flowers rises alongside increased interest in sustainable agriculture. However, growers in the region face persistent challenges, including a short and unpredictable growing season, limited land availability, high input and labor costs, and market saturation during peak months. This study draws from field interviews, survey data, and stakeholder engagement with flower growers, floriculture educators, and agricultural service providers across New England. It examines key production and marketing strategies that successful flower farms have adopted, including diversified cropping, succession planting, season extension, direct-to-consumer sales, and floristry integration. Additionally, this work highlights systemic needs in research, infrastructure, and technical assistance tailored to the ornamental crop sector. Findings emphasize the potential for expanded investment in floriculture education, cooperative distribution models, and grower networks to strengthen the viability of flower farming in the region. By elevating grower perspectives and showcasing practical innovations, this presentation contributes to the broader discussion on supporting ornamental crop producers through targeted outreach and research.

Speakers

Ankit Singh

University of Maine

www.aksapsjb.weebly.com

Tuesday July 29, 2025 2:15pm - 2:30pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf

2:30pm CDT

O/LT - Enhanced Detection of Japanese Maple Scale Using Cutting-Edge Artificial Intelligence Technology

Tuesday July 29, 2025 2:30pm - 2:45pm CDT

Strand 11A

The Japanese maple scale (JMS) (Lopholeucaspis japonica) is an armored scale insect that causes significant losses in the ornamental industry through direct injury, plant rejection, unmarketable stock, increased pest control costs, and restricted interstate plant movement. Ornamental growers typically identify JMS by visually inspecting trunks, branches, and twigs for waxy covers or by using sticky tape traps to monitor crawler activity. However, its microscopic size and camouflaged appearance make early detection challenging. This study aims to develop an artificial intelligence (AI)-guided, on-the-go pest scouting system to address the current challenges in early management of JMS in ornamental crop production. To develop the scouting system, a Sony ILX-LR1 professional camera with a 61.0 megapixel full-frame sensor and interchangeable E-mount lenses designed for detailed industrial applications is used to capture high-resolution images. A small amount of data has been collected so far, with plans to gather a larger image dataset during the summer months. In the initial analysis, captured images were sliced into smaller patches to make the microscopic JMS detectable. These sliced images were used to train a transformer-based AI model for detecting JMS. The trained model, tested on the small dataset, showed it could detect JMS with an Intersection over Union (IoU) of over 0.8. While the model shows potential for detecting microscopic JMS, comprehensive training and testing with a larger dataset are needed to validate its performance. Upon completion, the developed scouting technology will serve as an effective tool for early detection and management of JMS in nursery environments, reducing plant injury and rejection while improving profits for ornamental growers.

Speakers

Hasan Jahanifar

University Of Georgia

Co-authors

Karla Addesso

Tennessee State University

Md Sultan Mahmud

University Of Georgia

Tuesday July 29, 2025 2:30pm - 2:45pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf

2:45pm CDT

O/LT - Effects of Azospirillum Brasiliense on Zoysiagrass

Tuesday July 29, 2025 2:45pm - 3:00pm CDT

Strand 11A

Zoysiagrass is a popular choice for Florida lawns but requires supplemental fertilization and irrigation. Nitrogen-fixing bacteria, such as Azospirillum Brasilense (Azb), may improve nutrient uptake and rooting, potentially reducing fertilizer and irrigation needs. The experiment is taking place from Summer 2024 to Fall 2026 at the University of Florida, evaluates the effects of Azb on Zoysiagrass under varying nitrogen (N) and irrigation rates. The experiment uses ‘CitraZoy’ Zoysiagrass treated with three Azb products (Tazo-B, AzoPro Turf, Azo Root) and a non-inoculated control. Treatments are applied monthly at three N levels (100%, 50%, 0%) and two irrigation levels (100% and 75% recommended irrigation), using a randomized complete block design with four replicates per treatment. Weekly data collection includes normalized difference vegetation index (NDVI), visual quality, soil moisture, and digital image analysis. Statistical analysis is performed using ANOVA, with mean comparisons determined by Fisher’s Protected Least Significant Difference (LSD) at p ≤ 0.05. Results indicate that Azb products mitigate the impact of reduced irrigation on soil moisture. Combining Tazo-B or Azo Root with 50% N achieves an optimal balance of turf quality and sustainability. Additionally, Tazo-B with 100% N and 75% irrigation yields green cover comparable to fully irrigated treatments. These first-year findings suggest Azb enhances Zoysiagrass performance while reducing nitrogen and irrigation requirements. A second year of research will confirm these results, supporting the potential of Azb to improve turfgrass sustainability.

Speakers

VICTOR ABARCA

University of Florida

Co-authors

Alex Lindsey

University of Florida

Tuesday July 29, 2025 2:45pm - 3:00pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf
Poster # csv

3:00pm CDT

O/LT - Improving Turfgrass Vitality and Irrigation Efficiency with Compost Amendments

Tuesday July 29, 2025 3:00pm - 3:15pm CDT

Strand 11A

As climate variability increases and urban water demand rises, the turfgrass industry faces challenges in maintaining high-quality landscapes with limited irrigation. Water restrictions and escalating costs necessitate sustainable solutions to improve water efficiency without compromising turf performance. Research from the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) has shown that compost incorporation can enhance soil structure, increase plant-available water, and potentially reduce irrigation needs for warm-season turfgrasses in Florida. While initial studies demonstrated benefits for new landscape installations, limited research exists on established lawns. Our study aims to evaluate the influence of compost and fertilizer applications under varying irrigation conditions on turfgrass quality. This study, conducted in 2023 and 2024 at the UF/IFAS Plant Science Research and Education Unit in Citra, Florida, examines the combined effects of compost and fertilizer applications under different irrigation regimes. The experimental design had six distinct management practices: a control with neither compost nor fertilizer; compost topdressing once per growing season; combined compost topdressing and fertilizer application once per season; compost topdressing twice per season; both compost and fertilizer applied twice per season; and fertilizer alone applied twice per season. Irrigation was applied at 50%, 75%, and 100% of UF/IFAS recommendations. Compost was applied at 0.5 yd³/1000 ft², and fertilizer at 1.0 lb N/1000 ft². Results from statistical analysis consistently demonstrated that compost topdressing combined with fertilizer twice per season (CTD

Speakers

Jaspal Singh

University of Florida

Co-authors

Alex Lindsey

University of Florida

Eban Bean

University of Florida

Natasha Restuccia

University of Florida

VICTOR ABARCA

University of Florida

Tuesday July 29, 2025 3:00pm - 3:15pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf
Poster # csv

3:15pm CDT

O/LT - Assessing the Safety of S-Metolachlor as an Over-the-Top Pre-Emergent Herbicide on 'Denver Daisy' Black-eyed Susan (Rudbeckia hirta 'Denver Daisy')

Tuesday July 29, 2025 3:15pm - 3:30pm CDT

Strand 11A

Preemergence herbicides play a critical role in weed management but can pose challenges for ornamental plant safety during establishment. Black-eyed Susan (Rudbeckia hirta) cv “Denver Daisy” is a popular ornamental cultivar valued for its vibrant blooms and adaptability. An experiment was conducted in 2024 at the Southwest Research and Extension Center in Hope, AR to evaluate transplanted Black-eyed Susan tolerance to topically applied S-metolachlor. S-metolachlor was applied as a broadcast application at 0, 2.8, 5.6, and 11.2 kg ai ha-1 two weeks after Black-eyed Susan plants were transplanted into raised beds. Visual injury, plant heights, and plant widths were collected at 2- and 4-weeks after application. There was no visual injury at any rating, however, some damage from deer feeding on plants was observed so only plant widths are reported. Plant widths ranged from 9 to 10.5 cm at 2-weeks after treatment and 15.7 to 17.3 cm at 4-weeks after treatment, with no differences between treatment at either data collection timing. Data from this study suggests that topically applied S-metolachlor may be a viable residual weed control option for ornamental Black-eyed Susan.

Speakers

Anthony Bowden

University of Arkansas

Co-authors

David Nistler

University of Arkansas

Hannah Wright-Smith

University of Arkansas

Tuesday July 29, 2025 3:15pm - 3:30pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf
Poster # csv
Funding Source The IR-4 Project

3:30pm CDT

O/LT - Performance Assessment of Commercial Leaf Blowers Across Power Sources

Tuesday July 29, 2025 3:30pm - 3:45pm CDT

Strand 11A

The landscape maintenance industry is under growing legislative scrutiny for its environmental and noise impacts. Among professional tools, the leaf blower is most frequently targeted due to its high decibel output and widespread use. In response, advancements in battery technology have introduced commercial-grade battery-powered alternatives. Despite this progress, many landscape professionals remain concerned about the work capacity and efficiency of battery-powered blowers compared to traditional gas-powered models. This study evaluated commercial gas and battery leaf blowers through controlled laboratory tests measuring runtime, task efficiency, output force, and sound levels. Results showed that some battery-powered models operated longer on a single charge than gas-powered blowers on a single tank of fuel. However, gas-powered blowers were 24% to 200% more effective in completing standardized tasks when operated by experienced users. This advantage stemmed from their ability to maintain high, consistent output throughout operation. In contrast, most battery-powered blowers sustained peak performance only briefly before throttling output to conserve energy, reducing their effective work capacity. Additionally, several battery models failed to meet manufacturer claims regarding output force. While battery blowers offered quieter operation—producing 20% to 26% lower decibel pressures than gas units—the performance tradeoffs remain a concern for high-demand applications. These results highlight the disparity between power sources in leaf blowers, one of the most frequently used tools in landscape maintenance, and emphasize the current limitations and tradeoffs involved in transitioning to battery-powered equipment under regulatory pressure.

Speakers

Paul Bartley

Auburn University

Co-authors

Allison Link

Auburn University

Landon Erbrick

Auburn University

Mark Hoffman

Auburn University

Tuesday July 29, 2025 3:30pm - 3:45pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf
Poster # csv

3:45pm CDT

O/LT - Assessing Landscape Bed Temperature Dynamics and Light Transmission under Five Frost Protection Fabrics

Tuesday July 29, 2025 3:45pm - 4:00pm CDT

Strand 11A

Providing protection from winter elements and seasonal temperature shifts are important considerations for nursery growers and landscape contractors. Frost protection fabrics can provide additional insulation to sensitive plants by maintaining temperatures at more moderate thresholds; however, with a wide range of weights and materials on the market, it is necessary to understand the extent to which various frost fabrics can serve this purpose. Five frost cloth materials were evaluated over a three-month period (January through March 2025) at the LSU AgCenter Hammond Research Station, with individual landscape bed replicates covered with one of four different weights of a non-woven frost fabric, one woven frost fabric, or left uncovered. Landscape bed replicates were comprised of typical landscape bed media (i.e. aged pine bark and sand) with a steel edging frame and support hoops. Each replicate was provided with a temperature sensor below the bed surface and a temperature and light sensor at the bed surface. Sensors recorded temperature and light conditions every 30 minutes, providing insights towards ambient environmental conditions beneath the frost fabrics (or in open air) as well as within the landscape bed media. Uncovered plots received the most amount of light and were subject to the highest degree of variability in temperature; however, the frost protection fabrics provided varying degrees of light transmission and temperature moderation. The woven frost protection fabric allowed the greatest amount of light transmission for all frost protection fabrics investigated, where it also yielded higher surface and subsurface temperatures relative to non-woven materials and uncovered replicates. Non-woven frost fabrics of varying weights generally provided similar levels of insulation to each other; however, it was observed that heavier frost fabrics were capable of minimizing temperature fluctuations. All investigated frost fabrics were effective in raising the minimum surface and subsurface temperatures relative to the uncovered replicates. As the study (and spring season) progressed, peak temperatures under frost cloths were at times elevated above uncovered plots. The results indicate that frost cloths of various materials and weights provide different levels of insulation, and that careful attention to environmental conditions is necessary for deciding when to place and remove frost cloths in the field.

Speakers

Damon Abdi

Louisiana State University Agricultural Center

Tuesday July 29, 2025 3:45pm - 4:00pm CDT
Strand 11A

Oral presentation, Ornamentals/Landscape and Turf

Subject Ornamentals Landscape and Turf
Poster # csv
Funding Source Louisiana Nursery and Landscape Association

4:14pm CDT

WUM 1 - Oral Session

Tuesday July 29, 2025 4:14pm - 4:15pm CDT

Strand 11A

Presiding/Moderator

Carlene Chase

University of Florida

Tuesday July 29, 2025 4:14pm - 4:15pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management

4:15pm CDT

WUM 1 - Vegetable seedlings production via seed magnetization and magnetized water

Tuesday July 29, 2025 4:15pm - 4:30pm CDT

Strand 11A

this study aimed to assess how irrigation water and seed magnetization affected the initial growth of okra, bell pepper, cucumber, lettuce, and eggplant seedlings. Five treatments and four replications were used for each species in the randomized block design (RBD) experiment. T1 was irrigation with tap water; T2 was neodymium magnetization of seeds plus irrigation with tap water; T3 was commercial magnetization of seeds plus irrigation with tap water; T4 was lack of seed magnetization plus irrigation with neodymium magnetized water; and T5 was lack of seed magnetization and irrigation with commercial magnetized water. We assessed the following: emergence speed index (ESI), average emergence time (AET), emergence percentage (E%), shoot dry matter (SDM), root dry matter (RDM), number of leaves (NL), root length (RL), stem diameter (SD), and plant height (PH). Normality and variance analysis were performed on the data, and the Tukey test was used to compare the means at a 5% probability level. The study's findings demonstrate the advantages of magnetically treated water for seedlings. Using water that has been magnetized by a neodymium magnetizer produced superior results for lettuce seedlings. The highest RL, NL, RDM, and ESI values were obtained for bell peppers when they were irrigated with water that had been magnetized by a neodymium magnetizer. The time it took for cucumber, eggplant, and okra seedlings to form was shortened by either magnetizing the seeds or watering them with tap water. Overall, the results of seed magnetism have been more noteworthy than those of irrigation water magnetization.

Speakers

Gustavo Haddad Souza Vieira

Full Professor, IFES campus Santa Teresa

Agronomist,Ph. D. in Agricultural Engineering. Full Professor. Irrigation, Agrometeorology, Horticulture, Coffee Crop.

Co-authors

Paola Alfonsa Vieira Lo Monaco

Ifes Santa Teresa

Rafaela Melim Grazzioti

Ifes

Robson Celestino Meireles

Ifes Santa Teresa

Tuesday July 29, 2025 4:15pm - 4:30pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Funding Source Prodif Ifes. Edital PRPPG 07/2025.

4:30pm CDT

WUM 1 - H2grow System: A Climate Smart Solution for Water Conservation in Vegetable Production System

Tuesday July 29, 2025 4:30pm - 4:45pm CDT

Strand 11A

Agriculture continues to account for over 70% of global freshwater withdrawals, despite extensive research into water conservation methods in food production. A significant portion of this water usage is attributed to irrigation. In vegetable crops, the traditional raised bed system with plastic mulch can reduce irrigation application by minimizing evaporative losses. However, this system does not prevent water and nutrient losses to deep percolation or lateral movement outside the bed area. Therefore, this study evaluates an alternative raised bed system (H2grow), and compares its impact on water use, yield, and fruit quality in bell pepper production against the conventional raised bed system. Six treatments were tested, which included three nitrogen (N) application rates in both raised bed systems (bed type). A split-plot design was used, with bed type as the primary factor and nitrogen rates as the secondary factor. All treatments were replicated four times. Soil moisture sensors were used to trigger irrigation when soil moisture levels fall below 90% field capacity. Soil moisture, nutrient levels, and tissue nutrient content were monitored throughout the growing season. Yield and fruit quality (fruit wall thickness), were assessed at harvest. Preliminary results show that cumulative water use under the H2grow was 33% lower than the conventional raised bed, regardless of nitrogen application rates. This corresponds to a water savings of 1460 m³/ha. Although there were no significant differences in yield or wall thickness between bed types; the H2grow system showed promising potential over conventional beds with a p-value of 0.08 for yield and 0.06 for wall thickness. Nitrogen application rates had no significant effect on yield or fruit wall thickness, though fruit biomass was lowest under the low-N treatment. These findings demonstrate that the H2grow system significantly conserves water in bell pepper production and has the potential to reduce the water footprint in commercial vegetable production. As water conservation becomes an increasing concern in agriculture, this innovative technology offers a critical solution to address the growing challenge of freshwater use in food production.

Speakers

Timothy Ayankojo

Assistant Professor, Mississippi State University

Co-authors

Thomas Horgan

North Mississippi Research and Extension Center – Mississippi State University

Tuesday July 29, 2025 4:30pm - 4:45pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Poster # csv

4:45pm CDT

WUM 1 - Micro-sprinkler Systems for Reduced Water Use during Establishment and Freeze Protection of Field-grown Strawberries in Florida

Tuesday July 29, 2025 4:45pm - 5:00pm CDT

Strand 11A

Strawberry production in Florida traditionally relies on impact sprinklers for bare-root transplant establishment and freeze protection, leading to significant water consumption and potential nutrient leaching and runoff. This study assessed micro-sprinkler systems as alternatives to enhance water use efficiency while maintaining crop performance. The objectives were to (1) evaluate micro-sprinklers in research and commercial settings and (2) assess sprinkler distribution uniformity under different wind conditions. Field trials at the Plant Science Research and Education Unit in Citra, FL compared four micro-sprinklers to an impact sprinkler (control), measuring water use, plant vigor, and yield. The tested systems utilized Mini Revolver, SuperNet Jet, Mini-Wobbler, and Xcel Wobbler micro-sprinklers. The irrigation systems were arranged in a randomized complete block design with four replications. Additionally, lower quarter distribution uniformity (DUlq) tests with catch cans were conducted to evaluate sprinkler efficiency for freeze protection across varying wind conditions in Citra. The best-performing micro-sprinkler system was evaluated on a commercial strawberry farm in Plant City, FL in comparison with the grower’s Rotator sprinkler system. In Citra, all micro-sprinkler systems used less water than the impact sprinkler for bareroot transplant establishment and freeze protection. Water use was lowest with the Mini-Revolver, which decreased water use by 66% during establishment and 64% during freeze protection without adversely affecting plant survival or yields. Similar reductions were observed at the commercial farm, with water savings reaching 58% during establishment and 63% during freeze events. Significant variation in DUlq in response to wind conditions was observed among the sprinkler systems. Wind speeds >7 mph decreased DUlq, with the Mini-Revolver resulting in the lowest DUlq. However, at wind speeds 7 mph, which would decrease freeze protection effectiveness.

Speakers

Carlene Chase

University of Florida

Co-authors

Davie Kadyampakeni

University of Florida

Josue St Fort

University of Florida

Michael Dukes

University of Florida

Shinsuke Agehara

University of Florida

Vivek Sharma

University of Florida

Tuesday July 29, 2025 4:45pm - 5:00pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Funding Source Southwest Florida Water Management District

5:00pm CDT

WUM 1 - Applying a consistent deficit irrigation in cantaloupe melons to improve crop water productivity

Tuesday July 29, 2025 5:00pm - 5:15pm CDT

Strand 11A

Deficit irrigation is an agricultural practice that can enhance crop water productivity (CWP) when yields are not affected, and be a technique to support crop production under persistent droughts and reduced agricultural water availability. Over two seasons, we evaluated grafted and ungrafted cantaloupe melon (Cucumis melo L.) under three consistent irrigation regimes: 100% of field capacity (FC; full irrigation), and 70% and 50% irrigation volumes of the full irrigation, resulting in moderate and severe deficit irrigation treatments, respectively. Although the deficit irrigation treatments accentuated drought stress through the season, plants in the moderate deficit irrigation (70% FC) maintained their plant water status and slightly lowered stomatal conductance (gs) and photosynthetic rate (Pn) when compared to full irrigation. Under severe deficit irrigation (50%), plants had lower water potential than the full irrigation, and a reduction of 65% in gs and 47% in Pn, when compared to the full irrigation. The yields of the 100% and 70% irrigation treatments were similar in one year and lower for the 70% FC in the second year. The severe deficit irrigation had on average a 40% lower yield than the full irrigation. Overall, the moderate deficit irrigation had a 25% reduction in applied water, and either a similar or a higher CWP, depending on year, when compared to the full irrigation. Melon grafting did not improve yield under deficit irrigation conditions; however, it increased yield under full irrigation and low environmental stress (i.e., year). This study shows that melons can acclimate to lower water availability and sustain yields under a constant, moderate deficit irrigation, which can be an alternative for growers that face long-season droughts and lower irrigation water allocation.

Speakers

Felipe Barrios Masias

University of Nevada, Reno

Co-authors

Heinrich di Santo

University of Nevada, Reno

Tuesday July 29, 2025 5:00pm - 5:15pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Funding Source Western Sustainable Agriculture Research and Education (WSARE) program, project SW20-918; and the Nevada DRIVE program at UNR

5:15pm CDT

WUM 1 - Optimizing Woodchip Bioreactors for Nutrient Recycling and Pesticides Removal in Greenhouse Irrigation Return Water

Tuesday July 29, 2025 5:15pm - 5:30pm CDT

Strand 11A

Sustainable management of irrigation water is critical for soilless greenhouse production systems, particularly in ornamental plant cultivation, where agrochemical (pesticides, nutrients, and growth regulators) use is intensive. Recycled irrigation water carries agrochemicals from production surfaces, containers, substrates, and system components. Even at low concentrations, these compounds can be phytotoxic to sensitive crops or pose environmental risks if discharged. While recirculating irrigation systems improve water efficiency, they require the use of treatment technologies to remediate agrochemicals. Woodchip bioreactors, commonly used for nitrate removal, have also shown promise in remediating phosphates and pesticides. They provide a carbon source and growth matrix for diverse microbial communities. Typical anaerobic conditions facilitate denitrification, and the biofilm further increases the reactive surface area where pesticides can interact with degrading enzymes to enhance pesticide remediation. Integrating aerobic bioreactors as a secondary stage can promote dissolved organic carbon release and enhance degradation of certain pesticides. Hydraulic retention time (HRT) is a key design factor, influencing nutrient retention and pesticide removal by controlling contact time with bioreactor microbiomes. Shorter HRTs support nutrient recycling for irrigation reuse, while longer HRTs enhance nutrient and pesticide degradation through extended microbial processing. We evaluated the performance of a sequential two-stage non-aerated (stage 1) - aerated (stage 2) bioreactor configuration in reducing effluent pesticide concentration and load under varying hydraulic retention times (HRTs). Two two-stage systems, each consisting of two bioreactors, were installed at a Michigan wholesale greenhouse, treating recirculating operational water from an 11,500 m² production area. These systems operated for 160 days at HRTs of 30 (30HRT) and 60 minutes (60HRT) per stage, corresponding to bioreactor volumes of 1,135 L and 2,271 L per stage, respectively. Preliminary results indicate that both 30HRT and 60HRT systems treated an average daily volume of 36,225±2,395 L. Average recycled Total Nitrogen load was 91% and 2.6 kg d-1 for 30HRT, and 78% and 2.3 kg d-1 for 60HRTs, respectively. Phosphate and pesticide content is currently being analyzed, with early observations showing phosphate load shifts from non-aerated to aerated conditions. These results will be presented at the conference.

Speakers

Henry Gonzalez

Research Assistant/Ph.D. Student, Michigan State University

Co-authors

Gemma Reguera

Michigan State University

James Owen

USDA ARS

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

R. Thomas Fernandez

Michigan State University

Tuesday July 29, 2025 5:15pm - 5:30pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Poster # csv

5:30pm CDT

WUM 1 - Seeding Woodchip Bioreactors Improves Nutrient and Pesticide Removal from Irrigation Return Water

Tuesday July 29, 2025 5:30pm - 5:45pm CDT

Strand 11A

Irrigation return water (IRW) from the nursery and greenhouse industries contains agrochemicals (pesticides, nutrients, and growth regulators) that pose significant phytotoxic and environmental risks within the operation and to the surrounding ecosystem. Agrochemicals can contribute to plant injury, eutrophication, groundwater contamination, and ecological toxicity. Woodchip bioreactors offer a cost-effective, sustainable solution for contaminant mitigation by supporting diverse microbial communities. Under anaerobic conditions, woodchip bioreactors facilitate nitrate reduction, while biofilms enhance pesticide degradation via enzymatic activity. Hydraulic retention time (HRT) regulates the duration of contaminant-microbiome interactions, balancing nutrient recycling in IRW at shorter HRTs and enhanced pesticide degradation at longer HRTs. However, newly established bioreactors typically experience a lag phase before reaching optimal contaminant removal efficiency due to the time required for microbial communities to develop. In this study, we investigated the potential of seeding new bioreactors with biofilms from established systems to accelerate this transition. Thirty-six woodchip bioreactors were evaluated under three HRTs (4, 14, and 24 hours) and three seeding levels (0%, 5%, and 10%) over 170 days. Simulated IRW containing nitrate, phosphate, and eight pesticides (acephate, atrazine, bifenthrin, chlorpyrifos, cyazofamid, oxyfluorfen, sulfoxaflor, and thiophanate-methyl) was used to assess performance. Preliminary results indicate that the 10% seeding at 4HRT yields the highest total nitrogen removal (6.2 g/day), compared to the 5% seeding at 4HRT (3.1 g/day) and the unseeded treatment at 4HRT (2.8 g/day). This suggests that a higher microbial load, combined with a shorter retention time, may be the most effective approach for removing Total Nitrogen.

Speakers

Henry Gonzalez

Research Assistant/Ph.D. Student, Michigan State University

Co-authors

Christopher M. Ranger

USDA ARS

Gemma Reguera

Michigan State University

James Owen

USDA ARS

R. Thomas Fernandez

Michigan State University

Silvia Valles Ramirez

USDA ARS

Tuesday July 29, 2025 5:30pm - 5:45pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Poster # csv

5:45pm CDT

WUM 1 - Irrigation and Harvest Treatment Impacts on Romaine Lettuce Quality Grown in a Coarse-Textured Medium

Tuesday July 29, 2025 5:45pm - 6:00pm CDT

Strand 11A

In-situ resource utilization at the lunar surface has been proposed for food production during human exploration missions. However, lunar regolith’s sandy texture holds less plant-available water than most of Earth's fine-textured agricultural soils. Reduced gravity at the lunar surface limits drainage from containerized media, likely causing root-zone hypoxic stress without appropriate irrigation management. Sensor-based irrigation systems may mitigate these challenges by maintaining an optimal medium volumetric water content. Evaluating the palatability of crops is also crucial, though sensory evaluation is uncommonly included in crop production studies. Hence, this research aimed to quantify the effects of sensor- and time-based irrigation strategies on the development and growth of Lactuca sativa (lettuce) grown using two continuous harvesting techniques in a containerized Turface MVP medium, a coarse calcined clay aggregates. Lettuce seeds were sown in 48 containers filled with the Turface MVP (particle sizes 0.8-3.4 mm) premixed with 15N-3.9P-10K controlled release fertilizer. Additionally, 24 containerized media were left unseeded to serve as controls. The containerized media were randomly assigned to sensor- and time-based irrigation under “pick-and-eat” and “cut-and-sow” harvesting techniques. Sensor-based irrigation maintained volumetric water content at 0.40 m3·m-3 through frequent sensor scanning and automated irrigation when sensor readings fell below the setpoints, while the media at time-based irrigation management were irrigated to saturation once per day. Under the “pick-and-eat” method, sensor-based irrigation increased the leaf fresh and dry weights, and photosynthesis rate by 81%, 39%, 61%, respectively, compared with plants under time-based irrigation at the end of experiment. The “cut-and-sow” method resulted in lower leaf fresh and dry weights than the “pick-and-eat” under both irrigation treatments. However, sensor-based irrigation led to increases in the medium’s electrical conductivity, causing plants under salinity stress because the phosphorus, potassium, and magnesium concentrations in the leaf tissue increased compared with those under time-based irrigation. Sensor-based irrigation improved overall acceptability of samples under “pick-and-eat” in sensory testing, with 50% of respondents disliking the time-based samples. However, the "cut-and-sow" samples under time-based irrigation exhibited higher overall acceptability, though 75% or more testers liked both samples. Sensor-based irrigation improved the yield of lettuce under "pick-and-eat" method but caused salinity stress. Conversely, the "cut-and-sow" method led to lower yield, but improved plant palatability under time-based irrigation. Nevertheless, with higher yield, increased mineral content, and improved consumer acceptability, the “pick-and-eat” method under sensor-based irrigation demonstrates potential for sustaining continuous crop production.

Speakers

Nintya Avriantari

University of Wyoming

Co-authors

Brianna Drew

University of Wyoming

Chieh-Yun Chang

Utah State University

David Claypool

University of Wyoming

Drea Hineman

University of Wyoming

Gioia D. Massa

NASA Kennedy Space Center

Ji-Jhong Chen

University of Wyoming

Jill F. Keith

University of Wyoming

Scott B. Jones

Utah State University

Shawna M. McBride

University of Wyoming

Tuesday July 29, 2025 5:45pm - 6:00pm CDT
Strand 11A

Oral presentation, Water Utilization and Management 1

Subject Water Utilization and Management
Funding Source NASA EPSCoR Rapid Response Research (R3) Grant#: WY-80NSSC24M0162, Wyoming Space Grant Consortium Faculty Research Initiation Grant#: 80NSSC20M0113, University of Wyoming College of Agriculture, Life Sciences, & Natural Resources, Office of Research and Economic Development Designated, Department of Plant Sciences. Y-Cross Scholarship. United States Department of Agriculture National Institute of Food and Agriculture (NIFA) Plant Sciences Hatch Funds (WYO-631-22)

7:59am CDT

LOCSY 2 - Oral Session

Wednesday July 30, 2025 7:59am - 8:00am CDT

Strand 11A

Presiding/Moderator

Catherine Simpson

Texas Tech University

Wednesday July 30, 2025 7:59am - 8:00am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Subject Local Food Systems

8:00am CDT

LOCSY 2 - Healthy Harvest: Outcomes from a Local Food, Health and Wellness Pilot Program

Wednesday July 30, 2025 8:00am - 8:15am CDT

Strand 11A

Background: Community Supported Agriculture (CSA) programs have been found to promote numerous positive health and nutrition behaviors, including increased consumption of fruits and vegetables and increased knowledge and self-efficacy in cooking skills. The CSA model can capitalize on this fact by connecting with institutional health and wellness programs. Employers and health insurance companies have funds to support employee wellness and are increasingly interested in programs that focus on the connection between high-quality, nutrient dense foods and health and wellness. The purpose of this study was to assess the impact of a workplace-based local food health and wellness educational curriculum that was tailored to CSA members. Methods: Family and consumer sciences Extension educators enrolled participants (n=41) in the pilot program in two counties in Florida. The educational curriculum had 6 modules that were delivered bi-weekly over 12 weeks. Each module paired a nutritional topic with local food. Nutrition topics included US dietary guidelines, menu planning, healthy cooking, fruits, vegetables, proteins, whole grains, and legumes. Local food topics included the economic importance of buying local food, ways to purchase local food, seasonal cooking, and regional food specialties. The program had both an in-person and online component, and included fact sheets, educational lectures, and on-farm videos of farmers explaining local crops. Researchers used a matched pre- and post-test design which used theory of planned behavior to assess participants’ knowledge, attitudes, beliefs, and intentions to purchase local food. The National Cancer Institute’s Short Fruit and Vegetable Screener was used to assess dietary changes. Wellness was assess using the Centers for Disease Control and Prevention’s Health-Related Quality of Life survey. Results: Participants significantly increased their fruit (p= 0.003) and vegetable (p=0.003) consumption. Participants had significant improvements in wellness indicators, including fewer days that pain limited their activity (p= 0.001), they experienced anxiety (p= 0.015), they felt sad (p=

Speakers

Catherine Campbell

University of Florida

Catherine Campbell, PhD, MPH, is Assistant Professor and Extension Specialist of Community Food Systems in the Department of Family, Youth and Community Sciences at University of Florida’s Institute of Food and Agricultural Sciences (UF/IFAS). She conducts social science research... Read More →

Co-authors

Annie Wallau

University of Florida

Cody Gusto

University of Florida

Wendy Wood

University of Florida

Wednesday July 30, 2025 8:00am - 8:15am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Subject Local Food Systems

8:15am CDT

LOCSY 2 - Produce Waste Dominates Household Food Waste: Results from a Citizen Science Study

Wednesday July 30, 2025 8:15am - 8:30am CDT

Strand 11A

Background: In the US, roughly one-third of food is wasted, with 37% of that waste occurring in homes. EPA estimates households discard 6.5 pounds weekly. Household food waste is difficult to study because it occurs in the privacy of homes. Citizen science is a research method that enlists community members to collect in real-world conditions in contexts that researchers do not have access. Objectives: The purpose of this study was to collect primary data on households food waste, the primary reasons people generate food waste, the types of packaging households typically discard, and individuals’ knowledge, attitudes, and beliefs about food waste. Methods: A total of 159 citizen scientists (86 Alachua County, 73 Sarasota County) recorded data on their household food waste for 14 days, including recording the total daily weight, types of food discarded, types of food packaging discarded, and reasons for food and packaging waste. Results: A total of 3,823 pounds of compostable food waste was discarded by citizen scientists in two-week period. Households in our study discarded more than 14 pounds of food waste per week, more than double EPA estimates. Fruits and vegetables are the food groups that create the most food waste, with an average of 2.7 servings of fruit and 8.5 servings of vegetables discarded per household over the two-week period. Dinner yielded the most food waste, with household having an average of 36 servings of food wasted at dinner. More than 90% of participants rely on date labels to determine if food is safe to eat, 86% discarded food because it was “old,” and 69% discarded food because of blemishes/damage. Discussion: This multi-county citizen science study provides an initial look at the sources of food and packaging waste in Florida households, and highlights opportunities for future Educational programs focused on how to store and prepare fresh produce could reduce the largest source of household food waste to help address this global problem at the household level.

Speakers

Catherine Campbell

University of Florida

Co-authors

Cody Gusto

University of Florida

Ziynet Boz

University of Florida

Wednesday July 30, 2025 8:15am - 8:30am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Subject Local Food Systems
Funding Source This research was a part of the Integrated Food Waste Measurement and Predictions Supported by Agent-Based Models (IFWASTE) research project funded by the Foundation for Food and Agriculture Research and U.S. Department of Agriculture, National Institute of Food and Agriculture, Hatch project #1023901.

8:30am CDT

LOCSY 2 - Reinforcing Oklahomas Food Systems with Local Horticultural Production

Wednesday July 30, 2025 8:30am - 8:45am CDT

Strand 11A

The state of Oklahoma has a foundation in natural resources and agriculture. To date, despite growth and industry changes, Oklahoma has kept true to its history but operates through the lens of industrial agriculture. The horticultural market is largely untapped and overlooked within the state even with the ample resources, land availability, open market, and a population in need of nutritional supplementation. Connecting with and having conversations with Oklahoma vegetable and fruit producers reveal underlying problems within Oklahoma's local food system and programs which include the fundamentals of production, market accessibility, and distribution problems. These conversations have long-term implications on the future market of the state. The exploration of results found from the conversations will be explored in terms of programming available, and the future of Oklahoma’s food system. The current programming within the state has a variety of approaches to tackling the integration of a local food system or the promotion of specialty crops. The identification and systematic review of programming and policy will expose gaps and shortcomings in the Oklahoma food system. Identifying and understanding barriers in specialty crop producers will create opportunities to improve the methods of production in the state of Oklahoma. Through examining the states’ available resources, programming, and policies for fruit and vegetable producers in the state, a plan for success can be created to increase market access and profitability for producers while also increasing access to local produce for consumers in Oklahoma. The evaluation of Oklahoma’s policies and specialty crop programs or support networks have long term implications on the success of current markets for local vegetable and fruit producers, their challenges they face, and opportunities that lie ahead. The implications of this review will result in a better understanding, connection, and future resources to nurture and support the horticultural market. Keywords: Horticulture, local production, market accessibility

Speakers

Sophia Darrow

Oklahoma State University

Co-authors

Justin Quetone Moss

Oklahoma State University

Wednesday July 30, 2025 8:30am - 8:45am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Subject Local Food Systems

8:45am CDT

LOCSY 2 - Characterization of Nutrient Composition from Municipal and Commercial Compost Generated in Arkansas

Wednesday July 30, 2025 8:45am - 9:00am CDT

Strand 11A

Compost is treated as a waste product by many regulatory agencies, monitored and assessed only for its potential to harm humans or to harm the environment. However, horticulture practitioners are the number one consumer of compost, whether in nursery production, vegetable production, or home landscaping and gardening. In Arkansas, no state regulations require reporting chemical or physical characteristics of compost such as plant nutrient content, pH, bulk density, or organic matter content. Therefore, a statewide survey of participating Arkansas Department of Energy and Environment permitted composting facilities was conducted to characterize the availability of compost throughout the calendar year, the variability in plant nutrient content and physical characteristics. A total of 11 compost sites were sampled from nine compost production operations in Arkansas, including water treatment facilities, commercial depackaging companies, and municipal compost facilities. Yard waste (YW) was a component of all compost feedstocks, but some facilities could further handle food waste (FW) or biosolids (BS). Dry matter analysis found that composts from YW alone contained 1.31% to 1.92% N; composts from YW plus FW contained 2.57% to 3.70% N; and composts from YW BS contained 1.25% to 2.80% N. Major disparities were observed dry matter Na content when FW was included in compost. Composts including FW contained 2,185 to 7,672 mg/kg Na while composts from YW or YW BS contained 167 to 402 mg/kg Na. Present findings indicate that compost feedstocks affect the resulting nutrient content, particularly when introducing FW. Substrate testing beyond the standard testing for pathogens and trace metals will be critical for effective use of composts as a substrate or soil amendment in horticulture systems.

Speakers

Matthew Bertucci

University of Arkansas

Co-authors

Rachel Woody-Pumford

University of Arkansas

Wednesday July 30, 2025 8:45am - 9:00am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Subject Local Food Systems
Poster # csv

9:00am CDT

LOCSY 2 - Results of an Employer-funded Cost-offset Community Supported Agriculture Program

Wednesday July 30, 2025 9:00am - 9:15am CDT

Strand 11A

Background: Community-supported agriculture (CSA) programs have been found to promote health and nutrition, and consumers frequently cite healthfulness as a motivation for local food purchasing. The CSA model can capitalize on this fact and expand their customer base by partnering with healthcare providers or insurance companies that provide cost-offsets for people to enroll in CSA programs. The purpose of this study was to pilot test the impact of an employer-sponsored cost-offset CSA program. Methods: University of Florida (UF), Institute of Food and Agricultural Sciences Extension developed a collaborative partnership between cooperative Extension, local farms, and the UF Human Resources’ Office of Worklife to fund a cost-offset CSA program. Results: Seventy-seven employees purchased a cost-offset CSA membership. Participants were predominantly female (86%) and in staff positions (72%). Roughly a quarter of participants received food assistance (26%). The most prevalent motivations for joining the program were to support local farms (100%) and the local economy (96%). Ninety-two percent of participants joined the program to improve their diet and to eat food that tastes better. Some participants (36%) joined the program because they had been interested in join a CSA anyway. More than 80% of respondents were satisfied with all aspects of the program. Aspects that participants were not satisfied with was the cost of the CSA membership (18%) and the lack of information about the produce included in the CSA (16%). The overwhelming majority perceived that it improved their diet (92%), increased their fruit and vegetable consumption (88%), and increased their ability to cook seasonal produce (88%). Most participants (78%) indicated they would join a CSA again, with 86% saying they would join with the same farm again. Discussion: Feedback from participants was positive, with participants emphasizing personal benefits like weight loss and discovering new foods. Many indicated that this program was more valuable to them than traditional webinars or programs offered by the office of worklife. The farms appreciated that the program connected them with new customers and the ongoing partnership with UF, which has now entered its third year. Collaborative partnerships take time and effort to develop but can yield ongoing benefits for local farms and community food systems.

Speakers

Catherine Campbell

University of Florida

Co-authors

Cody Gusto

University of Florida

Wednesday July 30, 2025 9:00am - 9:15am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Subject Local Food Systems

9:15am CDT

LOCSY 2- School Gardening Leadership Certificate Program – Training School Teachers Sustainable Horticulture Practices

Wednesday July 30, 2025 9:15am - 9:30am CDT

Strand 11A

Seeding Success - The Louisiana Farm to School (F2S) Program sponsors a four-day intensive training targeting teachers and those that support school gardening and integrating gardens into the curriculum. The training has been offered each summer for the past five years with classroom and hands-on horticulture training in the mornings and in the afternoons, demonstration of classroom lessons linked to state standards, taste tests, and integration of farm to school into the classroom. The horticulture program focuses on the horticulture extension materials developed for the F2S program under the Sustainable School and Home Garden series, including the Louisiana Planting Guide and individual crop guides with all the materials available on the seedstosuccess.com website. Hands-on horticulture activities such as vermicomposting, composting, seeding and “bumping up” and planting transplants are introduced each day that are designed to be used in schools. All of the activities are intended to support the development and maintenance of school gardens and curriculum development. Participants provided feedback on the training and overwhelming benefited from the School Gardening Leadership Certificate Program. Data from the extension program will be presented including data on program, specific topics, and analytics.

Speakers

Carl Motsenbocker

Professor, Executive Director Louisiana Farm to School Program, Louisiana State University

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

Co-authors

Denise Cummins

School of Plant, Env. and Soil Sciences

Issabella Frank

Louisiana State University Agricultural Center

Wednesday July 30, 2025 9:15am - 9:30am CDT
Strand 11A

Oral presentation, Local Food Systems 2

Funding Source USDA Child Nutrition Funds

9:44am CDT

TECH - Oral Session

Wednesday July 30, 2025 9:44am - 9:45am CDT

Strand 11A

Presiding/Moderator

Marcelo Barbosa

University of Georgia

Wednesday July 30, 2025 9:44am - 9:45am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture

9:45am CDT

TECH - AI-Driven Yield Forecasting Using UAV-Based Imagery: Insights from a Pecan Orchard

Wednesday July 30, 2025 9:45am - 10:00am CDT

Strand 11A

Forecasting yield is a timely opportunity to make anticipated harvesting decisions on the grown crop and understand field variability. Such information is a remarkable contribution to the precision agriculture context. However, developing such an approach is challenging for perennial crops such as pecan. These crops present slight canopy changes, which often do not reflect the upcoming yield. Consequently, waiting for the harvest date is the only approach to obtain yield data. Conversely, the advent of image-based data and artificial intelligence techniques has proven their applicability in addressing this issue. Therefore, our objective was to analyze whether UAV multispectral images and AI-based data analysis are suitable for developing forecasting models for yield in pecan trees. Hence, we began collecting multispectral images approximately five months before the harvesting date. Each data collection date had an interval of fifteen days, totaling ten multispectral image sets. Subsequently, we processed the images to generate ten orthomosaics (one for each date). The orthomosaics were used to calculate numerous vegetation indices, texture data, and the canopy area to be used as inputs for the forecasting models. At the harvest date, we measured the yield of 78 individual plants across two pecan fields. Before developing the forecasting models, we performed a correlation analysis to better understand the relationship between the image data and yield. Afterward, we developed the forecasting models using machine learning algorithms, namely, multiple linear regression, decision tree, support vector machine, and random forest. The dataset was split into 70% (n = 55) for training and 30% (n = 23) for testing. The training dataset was used to train the forecasting models, while the testing dataset was used to assess the models’ effectiveness regarding precision (coefficient of determination, R²) and accuracy (mean absolute error, MAE; and root mean squared error, RMSE). All the models produced interesting results and could be implemented to forecast yield in pecan trees. However, random forest outperformed the others (high precision and accuracy) and, therefore, was the remaining model for this study. Forecasting yield in pecan trees presented increased effectiveness, improving the models’ performance early on and establishing higher accuracies closer to the harvesting date. We also performed a feature importance analysis, where predominantly the texture data contributed better to the models’ performance. Certainly, our findings are timely and support pecan growers and stakeholders in making better decisions for harvesting with anticipated and accurate yield data without waiting for the harvesting date.

Speakers

Marcelo Barbosa

University of Georgia

Co-authors

Lenny Wells

University of Georgia

Luan Oliveira

University of Georgia

Lucas Sales

University of Georgia

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

Regimar dos Santos

University of Georgia

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

Victor Martins

University of Georgia

Wednesday July 30, 2025 9:45am - 10:00am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture

10:00am CDT

TECH - Towards developing a unified model for non-destructive sugar content estimation in persimmon independent of genetic variability

Wednesday July 30, 2025 10:00am - 10:15am CDT

Strand 11A

Non-destructive estimation models often require cultivar-specific calibrations due to spectral differences arising from genetic variability. Integrating diverse cultivars into a single model can reduce costs and simplify data collection. However, in persimmons, the abundant and variable proanthocyanidins in the fruit overlap with spectral regions used for sugar estimation, rendering accurate prediction with a single model challenging. In this study, we attempted sugar estimation in diverse persimmon cultivars using near-infrared (NIR) spectroscopy and hyperspectral imaging. A total of 989 spectral measurements were acquired from 34 persimmon cultivars. Regression models employing various pre-processing and modeling techniques achieved a maximum R² of 0.786, indicating the feasibility of modeling sugar content across diverse cultivars with a unified approach. Furthermore, by designing a cover for the NIR sensor and combining it with SNV pre-processing, we demonstrated that stable spectra for sugar estimation can be obtained under outdoor conditions. With further improvements in accuracy, this approach is expected to facilitate rapid fruit quality evaluation and contribute to optimized production.

Speakers

Soichiro Nishiyama

Kyoto University

Co-authors

Airi Tomata

Kyoto University

Ryutaro Tao

Kyoto University

Wednesday July 30, 2025 10:00am - 10:15am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Poster # csv

10:15am CDT

TECH - Evaluating Leafy Greens Under Opaque and Thin-Film Semi-Transparent Photovoltaic Arrays

Wednesday July 30, 2025 10:15am - 10:30am CDT

Strand 11A

Combining green roofs with solar modules can protect plants and produce energy in cities. Growing crops in this system is called rooftop agrivoltaics (RAV) and can complement current urban agriculture efforts. We evaluated a group of five leafy green crops (arugula, kale, lettuce, spinach, and Swiss chard) under different solar modules over two years at two locations. Data measurements were taken for fresh and dry weight (FW, DW) stomatal conductance (SC), plant size at harvest (PSH), and microclimate data. Treatments included a polycrystalline opaque silicon module, a cadmium telluride (CdTe) frameless opaque module, a 40% semi-transparent CdTe module, and a full sun control. Four of the five leafy greens produced higher FW and DW under the 40% semi-transparent modules compared to other treatments and the full sun control, except spinach. Most species also produced larger PSH under the PV module treatments compared to the full sun control. Leafy greens under the module treatments resulted in lower SC, however, lettuce and Swiss chard grown under the semi-transparent module treatment produced higher SC compared to all other treatments. This research shows that incorporating photovoltaics on rooftop gardens influences the yield and stomatal conductance of select leafy green crops. While FW and DW mostly decreased under the deep shade treatments (opaque module, frameless module, and bifacial module) SC decreased, possibly due to less solar radiation on the leafy greens, reducing water use. Understanding the growth characteristics and growing environment of high value crops like leafy greens will increase understanding of what food crops are suitable for RAV systems.

Speakers

Armando Villa-Ignacio

Colorado State University

Armando Villa-Ignacio is a Ph.D. student under Jennifer Bousselot Ph.D. in the Department of Horticulture and Landscape Architecture at Colorado State University. He received his B.S. in Conservation from SUNY-ESF and his M.S. in Horticulture at CSU. He is currently researching raspberry... Read More →

Co-authors

Jennifer Bousselot

Colorado State University

Maria Chavez

New Mexico State University

Wednesday July 30, 2025 10:15am - 10:30am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Poster # csv
Funding Source Colorado Department of Agriculture Specialty Block Grant

10:30am CDT

TECH - Sensing the Airborne Alerts of Arugula Grown Under Salt Stress Using Low-Cost MQ Gas Sensors

Wednesday July 30, 2025 10:30am - 10:45am CDT

Strand 11A

Real-time monitoring of crop health is pivotal for advancing precision agriculture, enabling timely interventions to mitigate abiotic stress impacts. This study presents a novel and non-destructive approach for detecting salt stress in hydroponically grown arugula (Eruca sativa L.) using low-cost MQ gas sensors. Arugula seedlings, 11 days post-germination, were transplanted to a deep-water culture (DWC) hydroponic system in the greenhouse facility of The Pennsylvania State University. Salt stress was induced 9 days after planting by supplementing a modified Hoagland nutrient solution with sodium chloride (NaCl) at three concentrations: 0 mM (control), 40 mM, and 80 mM. Electrical conductivity (EC), pH and temperature parameters were regularly monitored during the cultivation period. Three MQ gas sensors—MQ2, MQ135, and MQ137—were integrated into a dome-shaped enclosure positioned over individual net pots, each containing four plants. To achieve a comprehensive volatile organic compound (VOC) profile, sensor units were strategically positioned on multiple plants within each treatment group. A total of 144 plants per treatment were cultivated, and two sets of sensor units recorded VOC emissions for 8 consecutive days. Salt stress significantly influenced plant growth, with fresh weight (FW) and leaf area decreasing as salinity increased. The 80 mM treatment exhibited the lowest FW and leaf area (61.69 ± 2.7 g, p-value = 0.015; 1434.25 ± 58 cm², p-value = 0.003), followed by the 40 mM treatment. All three MQ sensor responses revealed distinct VOC emission patterns correlating with salt stress levels. These sensor outputs were leveraged to train three machine learning models—K-Nearest Neighbors (KNN), Support Vector Machine (SVM), and Random Forest—to classify stress-induced VOC signatures. Among these, the cubic KNN model demonstrated superior predictive performance, achieving 98.73% accuracy, 98.74% precision, 98.73% recall, and an F1 score of 0.98 for the test dataset. These findings underscore the potential of cost-effective MQ gas sensors for real-time, non-invasive stress detection in crops, offering a promising tool for precision agriculture and early stress diagnosis. The integration of VOC sensing with machine learning models provides a scalable solution for enhancing crop management strategies in controlled environments.

Speakers

Ali Ahmad

Pennsylvania State University

Co-authors

Francesco Di Gioia

Pennsylvania State University

Jaime Lloret Mauri

Universitat Politècnica de València

Sandra Sendra Compte

Universitat Politècnica de València

Wednesday July 30, 2025 10:30am - 10:45am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Poster # csv
Funding Source This work was supported by the USDA-NIFA Specialty Crop Block Grants # C940001528 “Advancing the Sustainability of Indoor Urban Agricultural Systems”, the USDA-ARS Penn State Cooperative Agreement: 58‐6034‐3‐016 and by the Grant PRE2021-100809 funded by MICIU/AEI/10.13039/501100011033 and by European Social Fund Plus (ESF+). F. Di Gioia’s contribution was supported by the USDA National Institute of Food and Agriculture and Hatch Appropriations under Project no. PEN04723 and Accession no. 1020664.
Funding Option OREl or ORG funded all or part of the research associated with this abstract

10:45am CDT

TECH - Feasibility of Small- and Urban-Farm Agrivoltaics: Integrating Solar Energy Production with Specialty Crop Production

Wednesday July 30, 2025 10:45am - 11:00am CDT

Strand 11A

Land use is a major concern for our society, which impacts governmental regulations, industry and agriculture, and individual property owners. Agrivoltaics (APV) includes the combination of agriculture and photovoltaics energy production on a single plot of land. APV has been proposed as a way to integrate agriculture into large-scale photovoltaic arrays or integrate energy production into established agricultural operations. The objectives of this project were to establish replicated APV research trials with fixed vertical panel photovoltaic arrays and investigate the feasibility of growing various warm- and cool-season crops between them. Warm-season crops included tomato, watermelon, bush bean, and zucchini. Cool-season crops included fall-planted lettuce and beets as well as spring-planted spinach and lettuce. Vertical panels were constructed with four replications that examined systems effects of APV compared to the open-field. A split-plot randomized complete block design was utilized, whereby main plots included system and sub-plots were the crops. For each crop, yield, marketability, quality, and economic data were collected. Crop quality parameters tested included: visual quality, color, firmness, titratable acidity, and total soluble solids. Additionally, PAR sensors were located within crop rows to characterize light availability at the replicated site as well as at another solar array. Sensors were placed approximately 2.5’ above the ground surface to generally mimic mature plant canopy height, transversely across the expected light-treatment area. From the first year of study, similarities among the two systems (APV and open-field) were more numerous than significant differences. Only one statistically-significant treatment effect was found on crop yield, among one of two lettuce varieties grown in the fall (P

Speakers

Alex Thill

Kansas State University Olathe

Co-authors

Cary Rivard

Kansas State University

Eleni Pliakoni

Kansas State University

George Yang

Kansas State University

Logan Britton

Kansas State University

Wednesday July 30, 2025 10:45am - 11:00am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Funding Source KSU GRIP Project

11:00am CDT

TECH - A Graph Convolutional Network Approach for Hyperspectral Image Analysis of Blueberries Physiological Parameters Under Drought Stress

Wednesday July 30, 2025 11:00am - 11:15am CDT

Strand 11A

Blueberries are extremely susceptible to drought due to their shallow root systems and limited water regulation capabilities. Climate change exacerbates drought stress in major blueberry production regions, which affect key physiological traits, such as leaf water content (LWC), photosynthesis (A), stomatal conductance (gs), electron transport rate (ETR), photosystem II efficiency (φPSII) and transpiration rate (E). Current phenotyping methods for measuring these physiological traits are time-consuming and labor-intensive as well as limited by the need for specialized equipment. To address this, a high-throughput phenotyping (HTPP) platform integrated with hyperspectral camera and a novel graph convolutional network (GCN)-based model, Plant-GCN, was developed to predict physiological traits of blueberry plants under drought stress. Spectral reflectance obtained from the hyperspectral images were transformed into a graph representation, with each plant represented as a node, spectral reflectance as node features, and edges defined by spectral similarities. The Plant-GCN model utilizes graph convolutional layers that aggregate information from neighboring nodes, effectively capturing complex interactions in the spectral signature and enhancing the prediction of physiological traits. Plant-GCN achieved a coefficient of determination (R²) of 0.89 for LWC, 0.94 for A, 0.89 for gs, 0.92 for ETR, 0.93 for φPSII and 0.89 for E on the test dataset. The performance of the proposed Plant-GCN model was compared with multilayer perceptron (MLP), partial least squares regression (PLSR), support vector regression (SVR), and random forest (RF), and it consistently outperformed all these models as well as data published in other reports. The high-throughput phenotyping system enabled efficient large-scale data collection, while the Plant-GCN model captured long-range spectral relationships significantly improved the prediction of physiological traits. The high predictability of the models could facilitate the screening of blue-berry cultivars for the specified traits allowing the selection and breeding of new drought tolerant cultivars in the future.

Speakers

Md Hasibur Rahman

Auburn University

Co-authors

Tanzeel Rehman

AUBURN UNIVERSITY

Wednesday July 30, 2025 11:00am - 11:15am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Poster # csv

11:15am CDT

TECH - Advanced Spatio-Temporal Modeling for Bacterial Leaf Scorch Disease Scouting in Pecan Orchards

Wednesday July 30, 2025 11:15am - 11:30am CDT

Strand 11A

Bacterial leaf scorch is a harmful disease for pecan production, which can cause premature canopy defoliation, reduced kernel weight, and significant yield losses. The disease can cause a 10-13% reduction in shell nut weight and a 14-19% decrease in kernel weight, adversely affecting the quality and quantity of pecan yields. Early detection and precise management are important for minimizing economic losses and sustainable disease management. Current methods, such as manual scouting and conventional imaging, are inadequate for pecan orchards due to the trees' height and their inability to capture temporal changes or disease transmission patterns. Spatio-temporal modeling is a useful technique that enables tracking disease spread across time and location, identifying hotspots and transmission patterns to prioritize areas needing urgent intervention. This study aimed to develop a spatio-temporal model to visualize and evaluate the progression of bacterial leaf scorch disease in pecan orchards. High-resolution multispectral images of pecan trees were collected using a drone- mounted multispectral camera. A 3D point cloud was generated using Pix4D to create a reference NIR point cloud, and other vegetation indices point clouds were then aligned to provide sufficient data for model training. Ten vegetation indices, including the Normalized Difference Vegetation Index (NDVI), Green Normalized Difference Vegetation Index (GNDVI), Normalized Difference Red Edge Index (NDRE), Modified Red Edge Simple Ratio (MRESR), Enhanced Vegetation Index (EVI), Soil-Adjusted Vegetation Index (SAVI), Optimized Soil-Adjusted Vegetation Index (OSAVI), Atmospherically Resistant Vegetation Index (ARVI), Chlorophyll Index - Red Edge (CI_RE), and Simple Ratio Index (SR), were used to evaluate disease sensitivity. Individual tree canopies were segmented using the 3D DBSCAN algorithm for each index. A point transformer deep learning model was trained with 3D vegetation indices of each tree with the ground truth to develop the prediction ability of the model for classifying individual each tree disease severity level. The early results indicate that the model can classify disease severity in the 3D point clouds, capturing the disease stress in the individual tree. Additionally, integrating a temporal embedding layer into the trained model enables the transformer block to track changes in vegetation indices and quantify disease progression over time. The findings of this study facilitate the monitoring of disease progression and support site-specific management decisions, thereby enhancing the sustainability of pecan production.
Keywords: Artificial intelligence, Spatio-temporal modeling, Multispectral imaging, Spectral analysis, Drone-based Scouting.

Speakers

Shah Md Abul Hasan

University of Georgia

Co-authors

Md Sultan Mahmud

University of Georgia

Wednesday July 30, 2025 11:15am - 11:30am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Poster # csv
Funding Source Advisor

11:30am CDT

TECH - Preliminary Analysis of Computer Vision for Blackberry Flower Quantification

Wednesday July 30, 2025 11:30am - 11:45am CDT

Strand 11A

Precise and accurate quantification of blackberry flowers are essential for yield forecasting, phenotypic assessment, and enhancing management techniques in precision agriculture. Threshold segmentation of images for blackberry feature quantification could be challenging due to shadows and background variability, while manual flower estimation is subjective and time-consuming. The objective of this research was to apply artificial intelligence and computer vision to identify and quantify blackberry flowers from Unmanned Aerial Vehicle (UAV) remote sensing. A computer vision algorithm You Only Look Once (YOLO) was trained with 1142 image datasets of blackberry flowers to develop an image processing workflow to quantify UAV captured images. A performance analysis was conducted with YOLO variants (YOLOv8s–YOLO12s) for quantifying blackberry flowers. YOLOv10s achieved the best performance with a mAP@0.5 of 58%, precision of 60%, and recall of 58%. Input resolution had a notable impact, performing better at 1024×1024 pixels (mAP@0.5 = 55%) than at 640×640 (mAP@0.5 = 30%). Increasing the training dataset from 250 to 1,142 images progressively improved detection accuracy, highlighting the value of data volume for model generalization. Additionally, flower counts predicted by YOLOv10s showed a strong correlation with flower-to-vegetation ratio (FVR; r = 0.71, p < .001), supporting FVR as a practical proxy for estimating floral density in the field. A contribution to computer assisted agriculture integration in the blackberry industry has been made by investigating the performance of computer vision algorithms on blackberry flower detection. Challenges such as small and uneven sized flowers, overlapping occlusion, and plot-wise analysis must be further investigated. Keywords. UAV, automation, blackberry, phenotyping, artificial intelligence.

Speakers

Akwasi Tagoe

University o Arkansas

Co-authors

Aurelie Poncet

University of Arkansas

Cengiz Koparan

University of Arkansas

Donald M Johnson

University of Arkansas

Dongyi Wang

University of Arkansas

Margaret Worthington

University of Arkansas

Ramesh Bahadur Bist

University of Arkansas

Wednesday July 30, 2025 11:30am - 11:45am CDT
Strand 11A

Oral presentation, Technology Applications in Horticulture

Subject Technology Applications in Horticulture
Poster # csv
Funding Source This research was partially funded by the Hatch Project ARK02846

1:44pm CDT

EcoPhys 1 - Oral Session

Wednesday July 30, 2025 1:44pm - 1:45pm CDT

Strand 11A

Presiding/Moderator

Al Kovaleski

University of Wisconsin-Madison

Wednesday July 30, 2025 1:44pm - 1:45pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology

1:45pm CDT

EcoPhys 1 - Hydrogen cyanamide advances budbreak in grapevine by increasing rate of cold hardiness loss

Wednesday July 30, 2025 1:45pm - 2:00pm CDT

Strand 11A

The mechanism controlling dormancy in buds of woody perennial plants remains largely unknown. However, it is known that exposure to cold temperatures (chilling) promotes the transition from a non-responsive to a responsive status to growth-conducive temperatures (i.e., endo- to ecodormancy transition). In horticulture, hydrogen cyanamide (HC) has been used for decades to overcome chilling accumulation deficiencies for temperate fruit crops grown in subtropical climates. Given the connection between cold hardiness loss and budbreak, we hypothesized that HC would increase the rate of cold hardiness loss (deacclimation rate). To test this, we collected grapevine (Vitis hybrid ‘Petite Pearl’) cuttings from field conditions in Madison, WI in approximately bi-weekly intervals from December to April. Single node cuttings were prepared and randomly separated into two treatments: a control group [0.5% surfactant (Regulaid®, KALO, Inc.)], and an HC group [5% hydrogen cyanamide (Dormex®, Alzchem Group AG) and 0.5% surfactant]. Both groups were treated by submersion for 10s. Cuttings were then placed in cups of water, and under forcing conditions. The forcing conditions used for all collections were 22ºC and 16h light. In later collections, two additional forcing temperatures were used: 8ºC and 16ºC. Cold hardiness was measured using differential thermal analysis on the day of treatment application, from field collected buds (n>10), and in semi-regular intervals from cuttings under forcing conditions, with interval length depending on temperature [e.g., quasi-daily at 22ºC (T0 1d, T0 2d, …); about every two days for 16ºC (T0 2d, T0 4d, …), about every five days for 8ºC]. At each collection time and for each temperature and treatment, 10 cuttings were set apart to observe time to budbreak. As expected, budbreak occurred earlier in HC treated buds compared to control. Using measurements of cold hardiness over time under forcing, we determined deacclimation rates as the slope of linear regressions. The rate of deacclimation in the control group increased progressively with each collection, as chilling accumulated in the field (1.0ºC/d in December to 1.4ºC/d in March). However, the deacclimation rate of the HC-treated group was always greater than the control (1.6ºC/d in December and 1.7ºC/d in March). In March, at 16ºC, there was also a difference between control and HC group in deacclimation rate (1.2ºC/d and 1.4ºC/d), while there were no differences at 8ºC. HC increases the rate of deacclimation in grapevines. We anticipate that understanding the interplay between cold hardiness, deacclimation, and budbreak will be helpful in uncovering the dormancy mechanism.

Speakers

Al Kovaleski

University of Wisconsin-Madison

Co-authors

Erica Kirchhof

University of Wisconsin-Madison

Francisco Campos-Arguedas

University of Wisconsin-Madison

Michael North

University of Wisconsin-Madison

Nadia Arias

Universidad Nacional de la Patagonia San Juan Bosco / University of Wisconsin-Madison

Wednesday July 30, 2025 1:45pm - 2:00pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology
Funding Source Fulbright

2:00pm CDT

EcoPhys 1 - Evaluating Cold Hardiness Dynamics and Time to Budbreak of Dormant Grapevines Across the Continental US

Wednesday July 30, 2025 2:00pm - 2:15pm CDT

Strand 11A

Dormancy remains a poorly understood process in temperate woody perennial plants. These plants require cumulative exposure to low temperatures (chilling accumulation) during winter to respond to warm temperatures in spring (forcing) and properly break bud. For successful establishment of temperate woody perennial fruit crops, it is important to understand chilling accumulation and dormancy requirements of species and cultivars. Our recent work indicates cold hardiness is an important co-variate in the analyses related to timing of budbreak, and thus chilling accumulation models and dormancy progression studies. Here we set out to understand aspects of chilling accumulation in different conditions by evaluating two measures of dormancy progression, (i) a classic forcing assay, where time to budbreak is evaluated; and (ii) a newer phenotyping of cold hardiness deacclimation rates using grapevine (Vitis spp.). For a comprehensive analysis, we used grapevine canes from V. vinifera cvs. Cabernet Sauvignon and Riesling, and V. hybrid cvs. Concord, Frontenac, Itasca, Marquette, and Petite Pearl. Canes were collected in several states across the continental United States (CO, IA, MN, NY, PA, SD, TX, WI), and in two locations for two states (NY, WI), representing approximately eight different USDA Cold Hardiness Zones (4a-7b), over the course of two winter seasons (2023-2025). Collections occurred in December, January, February, and March of each season. Upon collection or receipt of shipments, initial cold hardiness of buds was measured using differential thermal analysis (DTA). Following, canes were prepared into single node cuttings, and placed in cups of water and in a growth chamber for forcing (22ºC, 16h day/8h night). A subsample of 15 cuttings was used to evaluate time to budbreak, while the remaining cuttings were used for cold hardiness measurements in semi-regular intervals. We used simple linear regression with cold hardiness measurements to determine deacclimation rates (loss of cold hardiness over time; ºC/day). In general, buds from warmer locations (IA, TX, and Long Island, NY) had less initial cold hardiness (field cold hardiness) than colder locations. Dormancy progression was faster in colder locations than warmer locations, observed in both budbreak assays and evaluation of deacclimation rates. Based on our data, time to budbreak is a function of initial cold hardiness and deacclimation rate. Future work will examine the response of deacclimation rates to chilling accumulation models to determine chilling models that best describe dormancy responses across climates, which will then be incorporated into models that predict field cold hardiness and field budbreak.

Speakers

Al Kovaleski

University of Wisconsin-Madison

Co-authors

Ali Didevarasl

University of Wisconsin-Madison

Amaya Atucha

University of Wisconsin Madison

Jason Londo

Cornell University

Michael North

University of Wisconsin-Madison

Wednesday July 30, 2025 2:00pm - 2:15pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology
Funding Source USDA National Institute of Food and Agriculture, Award No. 2023-68008-39274.

2:15pm CDT

EcoPhys 1 - Cellular Mechanism of Freeze-Injury Viewed Through Ionic Analysis of the Leachate from Spinach Leaves Injured at Varying Durations of Freezing

Wednesday July 30, 2025 2:15pm - 2:30pm CDT

Strand 11A

Freeze-desiccation due to exosmosis to extracellular ice is considered as the major stress during equilibrium freezing. This causes structural / functional perturbations in the plasma membrane which leads to leakage of cellular contents. To gain further insight into the cellular mechanism of freeze-thaw injury, four cations (K , Ca2 , Mg2 , Fe2 ), known for their critical roles in plant growth and development, were measured in the leachate from injured spinach (Spinacia oleracea L. ‘Reflect’) leaves exposed to four freezing-durations (FDs) (0.5, 3.0, 5.5, 10.5 h) at a fixed temperature. In general, leakage of K , Ca2 , Mg2 increased incrementally at longer FDs and leaves sustained greater water-soaking after prolonged freezing. Data indicated a higher abundance of reactive oxygen species (O2− and H2O2) in leaves with greater injury at longer FDs. PSII efficiency was incrementally compromised at longer FDs as determined by chlorophyll fluorescence (Fv/Fm). Total electrolyte leakage from tissues right-after-thaw versus those allowed to recover for 6-d revealed that injury at 0.5 or 3 h FDs was recoverable, but leaves were irreparably injured at 5.5 or 10.5 h FDs. K was the most abundant cation in leachate. Data suggests that K -leakage can be used as proxy for total electrolyte-leakage in determining LT50 and can serve as an ionic marker to delineate moderate (recoverable) versus severe (non-recoverable) freeze-injury. Ca2 - and K -leakage data, together, are compatible with an earlier conjecture that leaked K ions replace membrane-associated Ca2 during post-thaw. It is proposed that thus structurally weakened plasma membrane, together with inhibited active transport functions of plasma membrane (noted in previous studies) lead to enhanced K -leakage from more severely freeze-injured leaves. Unlike other cations, Fe2 -leakage was indeed lower in the injured (0.5 FD) leaves compared to unfrozen control. Moreover, Fe2 was undetectable in the leachate at longer FDs. It is hypothesized that such lack of Fe2 in the leachate could result from Fenton reaction in injured tissues which converts soluble Fe2 into insoluble Fe3 . Enhanced Mg2 -leakage at greater freeze-injury suggests structural/functional impairment of chlorophyll / chloroplast complex, resulting in reduced quantum yield of PSII.

Speakers

Rajeev Arora

Iowa State University

Wednesday July 30, 2025 2:15pm - 2:30pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology
Poster # csv

2:30pm CDT

EcoPhys 1 - Characterization of Fulvic acids-mediated Drought Tolerances in Tomatoes using Untargeted Hormonomics and Metabolomics Approaches

Wednesday July 30, 2025 2:30pm - 2:45pm CDT

Strand 11A

Drought stress poses significant environmental challenges to agricultural plants, especially tomatoes, by hindering their growth and reducing yields. Biostimulants like fulvic acids (FA) have emerged promising strategies for mitigating drought effects and enhancing water-use efficiency. However, the regulatory mechanisms of FA-induced drought tolerance are not yet fully understood. This study aimed to characterize FA-induced drought tolerance mechanism in tomatoes. Four-week-old plants were treated with FA at 240 mg per plant, and drought conditions were imposed by withholding 75% of the water supplied to well-watered plants. The plant growth performance and the physiological responses were evaluated. Leaf samples were collected at two stages: the early drought stage (3 days after treatment) and the later stage (7 days after treatment), for untargeted hormonomics and metabolomics analysis using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS). Under drought conditions, control plants exhibited significant stress symptoms, including reduced height and leaf wilting during the later phase. In contrast, FA-treated plants developed less drought symptoms and improved stomatal conductance. The hormonomics and metabolomics analysis identified 114 hormones and 243 metabolites in ESI . Using orthogonal partial least-squares discriminant analysis (OPLS-DA), we determined that 39 hormones and 162 metabolites (with a VIP score > 1.0) were significant discriminants among the different treatments. Under drought conditions, 2-hydroxy melatonin and abscisic acid (ABA) levels were significantly increased in FA-treated plants, along with higher concentrations of amino acids such as glycine and threonine. These findings suggest that fulvic acids modulate the phytohormones ABA and melatonin to induce drought tolerances, orchestrating a response that enhances drought tolerance by sustaining elevated levels of osmoprotective amino acids.

Speakers

Md Al Mamun

University of Tennessee

Co-authors

Ethan W. Darby

The University of Tennessee

Mahadi Hasan Redoy

University of Tennessee

Tabibul Islam

University of Tennessee, Knoxville

Wednesday July 30, 2025 2:30pm - 2:45pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology
Poster # csv

2:45pm CDT

EcoPhys 1 - New Methods to Assess Drought Resistance in Turfgrass

Wednesday July 30, 2025 2:45pm - 3:00pm CDT

Strand 11A

The irrigation of grasses dominates domestic water use across the globe, and a better understanding of water use and drought resistance in grasses is of undeniable importance for water conservation. Drought resistance is a complex trait composed of three distinct, but complementary, strategies: escape, avoidance, and tolerance. In grasses, drought escape is commonly displayed via summer dormancy, and drought avoidance and tolerance are displayed by grasses experiencing dehydration. Breeding programs have released cultivars with improved drought resistance, but the underlying mechanisms remain unknown. In this study, we used a number of plant physiology methods to characterize the mechanisms driving drought resistance in four zoysiagrass cultivars reported to exhibit contrasting levels of drought resistance. They were Lobo, Zeon, Empire, and Meyer. A dry-down was performed through deficit irrigation until 70% decline in evapotranspiration. No drought escape mechanism was identified in this project. Drought avoidance was characterized by the rate of dehydration over time, and drought tolerance was characterized by the decline in functional traits with increasing dehydration. Through this approach, we were able to separate avoidance from tolerance and demonstrate that drought tolerance governs drought resistance in commercial cultivars of zoysiagrass. Interestingly, we also demonstrated that canopy mortality during drought can only be reliably assessed using image analyses shortly after rehydration. This is because severe leaf rolling occurs during drought, confounding leaf rolling with actual leaf mortality. This study advances our understanding of i) drought resistance across commercial cultivars of zoysiagrass and ii) potential methods to select drought-resistant cultivars in turfgrass breeding programs.

Speakers

Amanda Cardoso

North Carolina State University

Wednesday July 30, 2025 2:45pm - 3:00pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology
Funding Source This work was supported by the Research Capacity Fund (HATCH), project award no. 7003279, from the U.S. Department of Agriculture’s National Institute of Food and Agriculture and the Center for Turfgrass Environmental Research and Education Board at NC State University.

3:00pm CDT

EcoPhys 1 - From Classic to Cutting-Edge: Optimizing Salinity Tolerance Detection in Brassica juncea

Wednesday July 30, 2025 3:00pm - 3:15pm CDT

Strand 11A

Salinity stress is a growing concern in agriculture, particularly as climate change accelerates soil salinization and limits freshwater availability. Here, we evaluated the effectiveness of classic (low-throughput) versus high-throughput physiological phenotyping methods in detecting early salinity tolerance in Brassica juncea cultivars (‘Carolina Broadleaf’ and ‘Southern Giant Curl’). Traditional phenotyping relies on point measurements such as shoot biomass and leaf gas exchange, which, while valuable, are time-intensive, offer limited temporal resolution, and can be destructive. In contrast, high-throughput phenotyping enables continuous, real-time monitoring of plant physiological responses, providing a dynamic and detailed understanding of stress adaptation mechanisms. We conducted a 42-day experiment in a controlled greenhouse environment, exposing mustard green cultivars to three salinity treatments: control (0.397 dS/m), moderate salinity (10.81 dS/m, ~20% of seawater), and high salinity (24.93 dS/m, ~50% of seawater). The high-throughput PlantArray system was used to measure key physiological parameters, transpiration rates, and net plant weight gain, while traditional phenotyping involved weekly surveys of including stomatal conductance, chlorophyll fluorescence, and biomass accumulation. We found that high-throughput phenotyping allows for earlier and more precise detection of salinity tolerance. Classic methods confirmed significant reductions in biomass, with shoot fresh weight decreasing by up to 80% in high-salinity treatments, but these differences were only detectable at harvest and not before. In contrast, high-throughput phenotyping revealed early signs of osmotic adjustment within the first 20 days, as plants initially maintained transpiration before exhibiting a decline due to ion accumulation. ‘Carolina Broadleaf’ resist moderate salinity, maintaining growth comparable to the control for the first 20 days, suggesting that early harvesting could mitigate yield losses. Overall, this study underscores the advantages of high-throughput phenotyping in improving the precision and efficiency of breeding programs. By integrating continuous physiological measurements, this approach enables earlier and more informed selection of salt-tolerant cultivars, reducing time needed for tolerance screening. Future research should focus on expanding these methods to operational conditions and integrating genomic data to enhance genotype-environment modeling for stress adaptation.

Speakers

Raiza Castillo

University of Florida

Co-authors

Cross Heintzelman

University of Florida

Elias Bassil

University of Cyprus

Gerard Sapes

University of Florida

Laura Torres

University of Floridaa

Marylou Mantova

University of Florida

Melanie Correll

University of Florida

Neus Alcon Bou

University of Florida

William Hammond

University of Florida

Wednesday July 30, 2025 3:00pm - 3:15pm CDT
Strand 11A

Oral presentation, Ecological Physiology 1

Subject Ecological Physiology
Funding Source USDA SAS CEA: 2506-207-2015906
Funding Option SCRI funded all or part of the research associated with this abstract

3:59pm CDT

HIH - Oral Session

Wednesday July 30, 2025 3:59pm - 4:00pm CDT

Strand 11A

Presiding/Moderator

Elizabeth Diehl

Director of Therapeutic Horticulture, University of Florida

Wednesday July 30, 2025 3:59pm - 4:00pm CDT
Strand 11A

Oral presentation, Human Issues in Horticulture

Subject Human Issues in Horticulture

4:00pm CDT

HIH - Using Nearby Nature to Increase Health

Wednesday July 30, 2025 4:00pm - 4:15pm CDT

Strand 11A

The role of nature in improving health is being explored in a growing number of healthcare fields. At the University of Florida, programs using nature-based interventions include physical medicine and rehabilitation, oncology, addiction recovery, Parkinson’s Disease, mental health, and autism, among others. These expanding program opportunities are slowly but steadily moving nature into the domain of public health. Some of the more recognizable examples of this trend are therapeutic gardens and nature prescriptions but there are many other ways to use nature to boost health in cities around the world. Spending time in green spaces (plant-dominated) and blue spaces (water-dominated) is linked to improved life satisfaction, reduced anxiety, and increased happiness. Nature exists on a spectrum and whether experiencing ‘big’ nature or ‘micro’ nature, high quality contact generates an increase in positive emotions and feelings of vitality, a decrease in negative emotions, relief from mental fatigue, and an improvement in our attention span. This presentation will explore research that highlights the health benefits of nature interaction, the primary components of high-quality nature experiences, and the key factors in connecting people and nature.

Speakers

Elizabeth Diehl

Director of Therapeutic Horticulture, University of Florida

Wednesday July 30, 2025 4:00pm - 4:15pm CDT
Strand 11A

Oral presentation, Human Issues in Horticulture

Subject Human Issues in Horticulture

4:15pm CDT

HIH - Indigenous Perceptions Of Agrivoltaics In The Navajo Nation: Insights From A Community-Based Assessment

Wednesday July 30, 2025 4:15pm - 4:30pm CDT

Strand 11A

The dissemination of agrivoltaic technology within Indigenous communities remains insufficiently understood, posing significant challenges to its successful implementation. As agrivoltaic systems continue to expand across the United States, it is imperative to examine how different social groups perceive and accept this technology. The Navajo Nation, the largest Indigenous tribe in the U.S., spans the Four Corners region, with the San Juan River Valley serving as a critical agricultural hub. To evaluate the feasibility of agrivoltaic adoption within this context, a sub-study was conducted as part of a broader Indigenous farmers’ needs assessment, focusing specifically on Navajo farmers in the San Juan River Valley. This study employed a qualitative survey consisting of eight binary-response questions to assess participants' knowledge of and interest in agrivoltaics. Results indicate that only 6% (n=126) of respondents were previously familiar with agrivoltaics, yet 88% expressed interest in learning more about the technology upon receiving an explanation. Furthermore, 73% of respondents were interested in exploring the use of photovoltaic systems to support their farms’ energy needs, although only 12% had prior experience with solar energy systems, underscoring key barriers to adoption. These findings suggest that agrivoltaic systems hold promise as a strategy for enhancing both local support for renewable energy development and food security within the Navajo Nation. However, significant knowledge gaps and limited technical expertise present obstacles to widespread implementation. The results emphasize the necessity of targeted educational and training programs to facilitate the successful integration of agrivoltaic systems. Without such efforts, adoption may remain limited due to a lack of familiarity and technical proficiency. Ultimately, this research underscores the potential for agrivoltaics to contribute to sustainable agricultural practices and renewable energy expansion within the Navajo Nation, highlighting the critical role of knowledge transfer and capacity-building initiatives in ensuring long-term success.

Speakers

Emiliano McLane

New Mexico State University

Emiliano McLane (Newe) is from the Tosawihi clan of the Te-Moak Tribe of Western Shoshone and was primarily raised on the South Fork Indian Reservation near Jiggs, Nevada. He is also a descendant of the Pomo, Wailaki, and Nomlaki tribes and spent part of his upbringing on his father’s... Read More →

Co-authors

Don Edgar

New Mexico State University

Kevin Lombard

New Mexico State University

Kevin Lombard is a Professor of Horticulture and Research Director of the New Mexico State University Agricultural Science Center at Farmington, a 250 acre research farm uniquely located on the Navajo Nation. His research encompasses specialty crop evaluations including grapes, fruit... Read More →

Olga Lavrova

New Mexico State University

Shannon Norris Parish

New Mexico State University

Wednesday July 30, 2025 4:15pm - 4:30pm CDT
Strand 11A

Oral presentation, Human Issues in Horticulture

Subject Human Issues in Horticulture

4:30pm CDT

HIH - The effect of a school gardening program on horticultural career interest, environmental locus of control, and climate anxiety among elementary-aged students

Wednesday July 30, 2025 4:30pm - 4:45pm CDT

Strand 11A

Climate anxiety among children is on the rise and research shows that discussing the issues and empowering youth are some ways to approach the issue. Historically, school gardens were used to teach children many subjects while addressing environmental issues and while fostering a love of plants and ecosystems. The objective of this study was to examine the influence of a 10-week outdoor, after-school youth gardening education program for first through third-grade students, specifically evaluating the effects on horticulture interest, environmental locus of control, and climate anxiety before and after participation in the program. The treatment group participated in an outdoor gardening program that involved hands-on learning related to growing plants and providing sustainable habitats while working through measures to create a National Wildlife Schoolyard Habitat as well as a recognized San Marcos Certified Habitat Stewardship Program landscape. The control group participated in the pre- and post-survey only and was not a part of the outdoor gardening or wildlife certification program, but was involved in other after-school activities offered at the elementary school. The survey questions were adopted from pre-determined, reliable, and valid instruments as well as adjusted for reading levels. Surveys utilized 5-point Likert scale questions with answer options employing emoticons that ranged from happy to sad. Pre- and post-survey data was analyzed through The Wilcoxon Signed-Rank tests and descriptive statistics. Data from this study determined the potential for school programs to increase horticultural interest in schools while empowering youth to make positive environmental action.

Speakers

Mackenzie Bark

Texas State University

Co-authors

Tina Waliczek Cade

Texas State University

Wednesday July 30, 2025 4:30pm - 4:45pm CDT
Strand 11A

Oral presentation, Human Issues in Horticulture

4:45pm CDT

HIH - Enhancing Foot Health and Safety in Farmers and Horticultural Professionals through Extension Education

Wednesday July 30, 2025 4:45pm - 5:00pm CDT

Strand 11A

Foot health in the workplace, particularly among farmers and agricultural professionals, is often neglected, despite its significant impact on overall health and well-being. In Florida, environmental conditions frequently lead to hot, damp feet, exacerbated by improper footwear, which contributes to poor foot health. Due to a reluctance to seek medical intervention, foot issues often progress to more severe complications. This commercial horticulture extension program aimed to improve foot health awareness, increase learning gains, and promote healthy behavior changes in agriculture and horticulture workers. Objectives: The primary objectives were: (1) to improve knowledge and skills related to foot health, and (2) to encourage the adoption of healthy foot care behaviors. Methods: A total of 238 clients were pre-surveyed from 2020 - 2024 to assess their foot health and identify areas of need. Participants were then invited to attend an extension program in-person or via webinar. Four classes were presented over the four-year span, focusing on foot health and safety, addressing issues like foot or leg pain, diseases, and deformities. Practical solutions were provided, including individual diagnostic assessments by a podiatrist/surgeon who demonstrated exercises and discussed the use of orthotics for improving foot health. Participants were encouraged to rate their foot health and report discomfort. A post-intervention survey was conducted three months later to evaluate changes in knowledge, behavior, and foot health status. Outcomes and Results: The pre-survey revealed that 69% of participants reported foot issues, with an average self-assessed foot health grade of 6.85 out of 10. After attending the educational session and implementing recommended practices, 98% of participants (n=25) reported significant relief from foot discomfort. Moreover, 95% committed to behavior changes, such as performing leg exercises, using orthotics, and changing footwear. The average foot health grade improved to 8.0 out of 10, representing an 11.5% improvement. Additionally, 96% (n=9) of participants shared their knowledge with 35 others, expanding the intervention's impact. Conclusion: This study shows that educational interventions focused on foot health can lead to significant improvements in knowledge and foot health outcomes among agricultural workers. The adoption of behaviors like using orthotics, performing exercises or consulting with a podiatrist resulted in measurable improvements. The widespread sharing of information indicates that the intervention had a positive ripple effect. Continued efforts to promote foot health in high-risk occupations are essential to prevent long-term complications and improve quality of life.

Speakers

Karen Stauderman

Commercial Horticulture Agent III, UF/IFAS Extension Volusia County

Wednesday July 30, 2025 4:45pm - 5:00pm CDT
Strand 11A

Oral presentation, Human Issues in Horticulture

Subject Human Issues in Horticulture
Poster # csv

5:00pm CDT

HIH - Comparison of United States Professional Florists’ Perceptions of Environmentalism and their Use of Sustainable Floral Design Practices Based on Geographical Regions

Wednesday July 30, 2025 5:00pm - 5:15pm CDT

Strand 11A

As environmental sustainability becomes increasingly important to consumers of fresh cut flowers, the educators of floral design should consider adding topics covering sustainability within the floral industry into their curriculums. Perceptions of sustainability can vary depending on the US region in which a person lives and works. The main purpose of this study was to compare the perceptions of environmentalism and the use of sustainable floral design practices currently being implemented by professional florists based on the geographical area in which they live within the US. By investigating florists' attitudes toward sustainability and their current practices based on the US region in which they live, this study sought to shed light on the current sustainable practices being implemented within the floral design industry so that educators can make informed decisions when modifying their curriculums depending on where they are located within the US. A majority of respondents from each region in the study indicated they were personally aware of sustainable products (75.4% overall) and mechanics (80.5% overall) in floral design. Differences were found in the sustainable practices being implemented by professional florists based on the US region in which they live. Overall respondents from the West indicated they used fair-trade products, sustainable and/or compostable containers, sustainable and/or compostable floral foams, recycled carboard, composted flower waste, and is attempting to eliminate plastic at a higher rate than other US regions. Based on what professional florists are currently implementing into their own business models and what consumers have indicated as being important sustainable considerations to them when making floral purchases in past research studies, topics that focus on sourcing locally grown fresh cut flowers, post-harvest care for specialty cut flowers, growing specialty cut flowers within limited space, methods for composting fresh cut flower waste, sustainable design techniques that can be incorporated into multiple design styles an occasions, and current sustainable floral products on the market for use in floral design are all example of sustainable topics that could be incorporated into a floral design curriculum.

Speakers

Lauren Baskins

Mississippi State University

Co-authors

Cole Etheredge

Mississippi State University

James DelPrince

Mississippi State University

Tina Waliczek Cade

Texas State University

Wednesday July 30, 2025 5:00pm - 5:15pm CDT
Strand 11A

Oral presentation, Human Issues in Horticulture

Funding Source This study was facilitated and funded by the Floral Marketing Fund (FMF), in cooperation with the American Floral Endowment (AFE), and co-sponsored by BloomNet® and Syndicate Sales.

5:15pm CDT

HIST - Evolution of ASHS Conferences: 60 Consecutive Years' Attendance

Wednesday July 30, 2025 5:15pm - 5:30pm CDT

Strand 11A

ASHS Annual Meetings (now conferences) have evolved over the 60 years of my attendance. From the 1965 Annual Meeting in Urbana Illinois where I stayed in a tent on the University quadrangle, to the most recent conference in Honolulu, they have been professionally stimulating, exciting and memorable. The dogwood pin given to attendees of the 1966 meeting with ISHS in Maryland, the long drive from St. Paul to College Station, Texas in 1967 and the ISHS/ASHS meeting in Davis stimulated my involvement and commitment to attending these important conferences. Involvement with the ASHS infrastructure began when I became a Board member representing the Great Plains Section when attending the meeting in Manhattan Kansas. I was immersed into the ASHS system further as the Chair of Local Arrangements for the 1972 meeting in St Paul (remember the chicken fiasco?) The Guelph meeting in 1974 was memorable because I attended "on the way" to sabbatical at the University of Nottingham and was "on the way back" to the 1975 meeting in Honolulu (September meeting). It was an easier drive from St. Paul to Ames in 1982 where I took my grad students in a van to save them money (I have always encouraged my students to become ASHS members by paying for their first year's memberships). Past President Dermot Coyne sponsored me for ASHS Fellow, awarded at the meeting in East Lansing in 1988. My second meeting in Honolulu was of note because following inducements of pineapples, luau and more, I purchased a timeshare to make sure that I'd take a "real" vacation in addition to my usual tacking on a few days to ASHS conferences. Among the important changes with which I had the privilege to assist was the creation of the ASHS Endowment Fund, and now the "$125 for Five" campaign that will continue to help deserving students. Of course I am humbled to say that one of my greatest honors was election as President of ASHS. Following the devastation wrought by Hurricane Katrina, I was inundated with "where can we meet", "when can we meet" emails and calls. I was proud to respond that we will help New Orleans by following through with our commitment to meet there. I will mention many more important ASHS changes and insights as part of my presentation this year as we return to the site of my Presidential Address in the "Big Easy".

Speakers

Paul Read

University of Nebraska

Wednesday July 30, 2025 5:15pm - 5:30pm CDT
Strand 11A

Oral presentation, History of Horticultural Science

Subject History of Horticulture
Poster # csv

5:30pm CDT

HIST - Gardening During the World Wars – Horticulture Efforts to Feed the US and the War Effort

Wednesday July 30, 2025 5:30pm - 5:45pm CDT

Strand 11A

The United States during the national crises of the First and Second World Wars developed gardening and food production programs in order to support the war effort and to supply food for the troops and those at home. The National War Garden Commission, a private organization, was created in 1917 one month before the US entry in World War 1. The role of the commission was to encourage US citizens to cultivate in all available space, offering free seeds and plants and to “Sow the Seeds of Victory!” President Woodrow Wilson in 1917 indicated “everyone who creates or cultivates a garden helps,” and tasked government agencies with aiding the effort to conserve food and other supplies for soldiers. The civilian garden program was supported by the commission who gave away free booklets on gardening, canning, and food preservation. These gardens, termed “war gardens” were grown throughout the country on vacant land, parks, backyards, and schools; there was call for schools to join the United States School Garden Army. There were many war gardens in the USA and around the world. There were more than 5.2 million war gardens in the USA by 1918. Towards the end of World War 1 the effort shifted to victory gardens with the goal of feeding the hungry, and prevention of starvation. With the advent of World War 2 the victory gardens were mobilized to provide resources to fight the war and support the US allies. Almost 20 million Americans planted gardens – in backyards, vacant lots, athletic fields, schools, roof tops. Produce from their gardens would help to lower the price of vegetables needed by the US War Department to feed the troops, thus saving money that could be spent elsewhere on the military. An estimated 40 % of the nation’s fresh vegetables were produced in victory gardens. The federal government, via the USDA provided resources such as seeds, production guides, and guidance in order to support victory gardens. The guides were intended to provide information to novice gardeners on growing food as well as proper canning and preservation techniques. The current farm to school movement and the People’s Garden program have their roots in the previous wartime efforts in order to support a more diverse resilient food system and address issues such as food access and climate change.

Speakers

Carl Motsenbocker

Professor, Executive Director Louisiana Farm to School Program, Louisiana State University

Wednesday July 30, 2025 5:30pm - 5:45pm CDT
Strand 11A

Oral presentation, History of Horticultural Science

Subject History of Horticulture
Poster # csv

7:59am CDT

TCHG 2 - Oral Session

Thursday July 31, 2025 7:59am - 8:00am CDT

Strand 11A

Presiding/Moderator

Cynthia Domenghini

Kansas State University

Thursday July 31, 2025 7:59am - 8:00am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods

8:00am CDT

TCHG 2 - Creating a Course to Target Self-Efficacy and Interest in Horticulture among Non-Horticulture Majors

Thursday July 31, 2025 8:00am - 8:15am CDT

Strand 11A

The Department of Horticulture and Natural Resources at Kansas State University offers a horticulture course for non-horticulture majors introducing students to an overview of the subject matter. This in-person, 16-week course provides hands-on learning and may be a tool to increase awareness of the horticulture industry while recruiting students to enroll in additional horticulture courses. Enrolled students were surveyed at the beginning of the semester and again at the end to evaluate changes in their self-efficacy and interest in horticulture as a future career and/or hobby after participation in the course. Twenty-nine students participated in both surveys over the two semesters data was collected. Survey responses required participants to indicate on a scale of one through five how strongly they agreed (5) to disagreed (1) with each statement in relation to the course. The data from the two semesters was compiled to create one dataset. Responses for each question were averaged and the differences between pre and post surveys were calculated to evaluate change. Results indicate positive change from pre- to post-survey in each area, though the differences were most notable in three categories. Student interest in pursuing horticulture as a hobby and as a career increased by one and two scale values respectively shifting from neutral or disagree to agree in both areas. Another area that showed this level of change was the prompt “I plan to recommend this course to others”. The difference from pre to post was one scale value shifting from neutral to agree. These results, along with the other positive results suggest the course may provide opportunities to increase student interest in horticulture and recruitment of new students to the program. Future students will be surveyed as the course is offered to add to the dataset informing the efficacy of this course as a recruitment tool.

Speakers

Cynthia Domenghini

Kansas State University

Thursday July 31, 2025 8:00am - 8:15am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods

8:15am CDT

TCHG 2 - Developing a University Campus Tree Inventory as a Tool for Sustainability, Student and Community Education

Thursday July 31, 2025 8:15am - 8:30am CDT

Strand 11A

University campus trees provide valuable ecosystem services to the surrounding community while directly and indirectly supporting numerous United Nations Sustainable Development Goals. The purpose of this project was to develop a GIS-supported tree inventory, in conjunction with a service-learning course, to support Tree Campus USA initiatives and maintain a collection of woody plant materials on the Texas State University campus. Horticulture students in a Woody Plants course applied their expertise through use of the ArcGIS FieldMaps mobile app to record the tree inventory on campus. GPS functionality allowed students to digitally map tree location points that contained identification, size, health and maintenance recommendations for each tree. The data were made accessible for select specimen through mounted QR codes on the trees. While the benefits of urban vegetation have been widely studied, tree inventories can provide guidance to facility crews for appropriate planting and maintenance based on the needs of the local environment. Furthermore, the data obtained through a campus tree inventory provided a tool to support campus sustainability initiatives and information demonstrating the economic and environmental values campus trees provided.

Speakers

Tina Waliczek Cade

Texas State University

Co-authors

Alberto Giordano

Texas State University

Jasmin Cruz

Texas State University

Thursday July 31, 2025 8:15am - 8:30am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods

8:30am CDT

TCHG 2 - Incorporating a “Food Waste as Fertilizer” Module into Instruction of Horticulture Courses

Thursday July 31, 2025 8:30am - 8:45am CDT

Strand 11A

Up to 40% of the food supply in the United States is wasted, but much of it could be repurposed as fertilizer. Learning modules were developed to introduce undergraduate students to the concepts surrounding food waste and extreme weather, the potential for a future circular bioeconomy that integrates the food-energy-water-waste-nutrient nexus, and the use of organic fertilizers in hydroponic systems that such processes will require. “Food Waste as Fertilizer” learning modules were integrated into the instruction of undergraduate coursework in horticulture at Kansas State University (KSU; HORT 705 Hydroponic Food Production) during Spring 2024 and Arizona State University (ASU; ABS 314 Applied Plant Physiology and ABS 464 Desert Horticulture) during Fall 2024. Impact of the modules on changing student perceptions and knowledge were evaluated with pre- and post-surveys administered just before and after the module intervention. Matched pairs were analyzed using the Wilcoxon Signed Rank Test for the ordinal data. At KSU (n=17), the learning module resulted in a positive shift in perception of students in response to 1) their interest in using organic fertilizer during hydroponic production, and 2) reporting that using organic fertilizers would be standard practice in the future. Other knowledge and perception survey items were not different between the pre- and post-tests. At ASU (n=15), students showed 1) a greater interest in applying organic fertilizers and 2) increased confidence in their ability to successfully grow hydroponic crops using organic fertilizers. Additionally, students recognized that optimizing processing methods and growing conditions could enhance the quality and performance of organic fertilizers. These findings suggest that "Food Waste as Fertilizer" learning modules successfully enhanced students’ understanding and confidence in using organic fertilizers in hydroponic systems. The positive shifts in perception at both KSU and ASU demonstrate the potential of such educational interventions to promote sustainable horticultural practices. Additionally, students recognized the importance of optimizing fertilizer processing and growing conditions, highlighting the role of innovation in improving fertilizer performance for future horticultural practices.

Speakers

Kimberly Williams

Kansas State University

Co-authors

Yujin Park

Arizona State University

Thursday July 31, 2025 8:30am - 8:45am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods

8:45am CDT

TCHG 2 - Keep It Simple: Bilingual Booklet Boosts Landscape Best Practices

Thursday July 31, 2025 8:45am - 9:00am CDT

Strand 11A

Florida’s massive environmental horticulture industry generates over $10 billion annually and employs over 100,000 individuals, with 33% identifying as Hispanic/Latino. The landscaping sector plays a crucial role in this industry, yet many positions lack formal certification, leaving training dependent on in-house instruction that varies in quality. Teaching Best Management Practices (BMPs) and Integrated Pest Management (IPM) practices to landscape professionals often involves navigating language barriers, varying levels of formal education, and limited training time. To address these challenges, a team of UF/IFAS Extension agents secured a USDA-NIFA IPM Extension grant in 2021 and developed a bilingual (English/Spanish) landscape reference booklet rooted in the principles of cognitive load theory and adult learning. Grounded in the KISS (Keep It Simple, Stupid) model, the booklet emphasizes clarity, brevity, and relevance—hallmarks of effective educational design for working adults. The tool features simple language, annotated photographs, and minimal text to reduce extraneous cognitive load and enhance information retention. Visual cues and side-by-side translations support dual coding and help bridge comprehension gaps. Finally, the booklet is pocket-sized and waterproof allowing for in-field deployment. Since its April 2024 publication, the booklet has reached a wide audience, with 366 copies distributed through Extension outreach of which 216 were distributed after a 1 – 2-hour class in English or Spanish on the topic. Its impact became evident as 164 individuals completed Qualtrics post-class surveys, with 99% (162) planning to use the information in their home landscapes and 63% (103) intending to apply practices on the job—44% (72) of whom believed the booklet would directly support BMP adoption among multilingual teams. Post-class surveys reported 80% (131) increased BMP knowledge. A 3–6-month follow-up survey confirmed sustained impact, as 85% of respondents (41 of 48) reported applying the information, and at least 83% (40) implemented one or more BMPs. Beyond its educational success, the booklet has gained traction within the industry. The UF/IFAS Bookstore sold 100 copies, generating $1,600 in revenue, while Extension Agents and industry trainers have formally adopted it as a standardized training tool. By starting with the basics and addressing language barriers, this initiative is empowering Florida’s landscaping workforce, fostering sustainability, and synergizing resilience. This project demonstrates how applying the science of simplicity can increase the effectiveness of Extension materials, particularly for linguistically diverse audiences. The format is easily replicable, adaptable to other horticulture topics, and well-suited for Extension’s fast-paced, field-based educational environments.

Speakers

HANNAH WOOTEN

UF/IFAS

Co-authors

Morgan Pinkerton

UF/IFAS Extension Seminole County

Tatiana Sanchez-Jones

UF/IFAS

Tina McIntyre

UF/IFAS Extension

Tina McIntyre is the Florida-Friendly Landscaping™ Agent at the UF/IFAS Extension in Seminole County. She specializes in surface water quality and quantity, best management practices related to landscape management, and restoration of urban green spaces. Tina came to Extension after... Read More →

Thursday July 31, 2025 8:45am - 9:00am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods
Poster # csv
Funding Source USDA-NIFA

9:00am CDT

TCHG 2 - Efficacy of podcasting as an extension format

Thursday July 31, 2025 9:00am - 9:15am CDT

Strand 11A

Podcasting is an underutilized extension format, and little information exists as to its efficacy as a teaching tool. One extension podcast is Growing the Valley (GtV), which focuses on tree fruit and nut production in California’s Central Valley. Topics cover research updates, best management practices, and discussions of current events. Irrigation and nitrogen management episodes were made available for an online, on-demand continuing education credits for a certification program in California focused on reducing nitrogen losses from agricultural fields. A optional short survey was embedded in the credit program to gauge user’s knowledge of topics discussed in the episodes before and after listening. Results indicate that GtV listeners showed significant gains in knowledge, suggesting that this format is an effective educational tool for extension personnel.

Speakers

Phoebe Gordon

University of California

Co-authors

Luke Milliron

University of California Agriculture Natural Resources

Rachel Shellabarger

University of California, Agriculture and Natural Resources

Thursday July 31, 2025 9:00am - 9:15am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods
Poster # csv

9:15am CDT

TCHG 2 - A Review of Introductory Horticulture and Plant Science Classes In US Colleges and Universities: A national survey of co

Thursday July 31, 2025 9:15am - 9:30am CDT

Strand 11A

A survey of the structure and contents of introductory horticulture and/or plant science classes was developed to understand common content, laboratories, and resources used across the U.S. The survey was distributed by email to 267 universities and colleges comprised of 1864 and 1890 Land Grant institutions, public state universities, colleges, technical schools, tribal colleges, and private institutions. Responses were received from 104 institutions, a 39% response rate of which 30 responses did not complete sufficient information to be included. The majority of responses came from Carnegie R-1 or R-2 institutions (51%) which had research programs along with undergraduate programs. Of the respondents, 42% were from designated horticulture departments or units, 26% from combined plant science units, 17% agriculture departments, and 14% responded “other.” Of the respondents, 47% offered degrees in horticulture, 21% a degree in plant sciences, 11% a degree in agriculture, and 21% “other.” Faculty instructing an introductory horticulture or plant science course were most commonly tenure track (64%) or nontenure track (35%) instructors. Full professors were the most common faculty instructors (45%), followed by assistant professors (20%). For 87% of the respondents, the course served as a degree requirement, was required for upper-level courses within the program (78%) and was commonly a university general education accepted course (59%). Two thirds of the courses had a required textbook while the remaining course had an optional textbook or had no textbook. The mode of learning was face-to-face (53%) or hybrid and asynchronous on-line (14%). The majority of courses (68%) were lecture-based delivery. The approach to the course was science based (55%) or a balance of science and practical technology (45%). The ranked topics covered in the course (from most frequent to least frequent) were plant growth and development, environmental effects, plant anatomy, plant nutrition and fertility, plant physiology, plant classification and nomenclature, plant chemistry, plant genetics and breeding, and history of horticulture. The rank of disciplines taught or emphasized in the courses were greenhouse operations and management, ornamental and nursery production and operation, landscape management, vegetable production and management, fruit production and management, arboriculture, and turf production and management. These results, and others presented, will help instructors in introductory horticulture and plant science courses develop course content that is commonly used across the U.S. and could be used to establish standards for learning outcomes.

Speakers

Curt Rom

University Professor. And Associate Director, University of Arkansas and ASHS

Co-authors

David Kopsell

Illinois State University

Michelle M. Wisdom

University of Arkansas

Thursday July 31, 2025 9:15am - 9:30am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods
Poster # csv

9:30am CDT

TCHG 2 - Teaching Research Methods by Developing Production Recommendations for Various Philodendron Cultivars Grown in a Central

Thursday July 31, 2025 9:30am - 9:45am CDT

Strand 11A

Plugs of various Philodendron cultivars, such as ‘Moonlight’, ‘Green Princess’, ‘Birkin’ and ‘Imperial Green’ are readily available to Florida commercial foliage growers. Although older generalized recommendations for producing philodendrons exist, specific production guidelines are not available for many newer cultivars. Growing a crop of foliage plants like philodendrons to completion not only provides for development of grower guidelines but also provides excellent research method learning experiences for undergraduate students. Each year, in September, tissue-cultured plugs of various philodendrons are potted up in 15.24cm standard pots using conventional peat/perlite soilless mixes amended with dolomite, STEM, and several different rates of various controlled-release fertilizers (CRF). The pots are placed on greenhouse benches in randomized blocks within a split-plot design under two different shade levels. The controlled-release fertilizers (CRF) should release evenly at soilless medium temperatures up to 30°C. Throughout the production schedule (usually September to March), medium temperatures are measured using Onset HOBO MX2202 Bluetooth data loggers buried in several pots; light level, temperature and humidity at plant height are also measured. All pots receive the same irrigation treatment. Non-destructive plant growth parameters, such as plant height and number of leaves, are collected frequently. Leaf chlorophyll content is measured several times using various different chlorophyll meters. Leaf color is measured with various color meters. Electrical conductivity (EC) and pH for all pots are measured using the standard pour-through method to evaluate the overall fertilizer levels available; these leachate sample solutions are collected and evaluated in the lab for nitrate, phosphate, potassium, calcium, and magnesium concentrations in the leachate solutions using different types of meters. At the end of the six-month growing period, plants are moved to another location, randomized, and then evaluated by student buyers not involved in the production of the crop. This marketing survey allows us to check for differences between treatments that might impact consumer acceptance. Destructive measurements, such as leaf chlorophyll content and/or leaf chemical content can also be measured after the marketing survey. Statistical analysis is also performed on the collected data. Since the data types are varied, students are introduced to several different statistical techniques from standard deviation to variance to correlation to regression. After completion of the production study, student participants often publish manuscripts and give presentations at conferences. Grower production recommendations are also offered.

Speakers

John L Griffis Jr

Florida Gulf Coast University

Co-authors

Krystin Perry

Florida Gulf Coast University

MADELEINE TENNY

Florida Gulf Coast University

Malcolm Manners

Florida Southern College

Rory Dunn

Florida Gulf Coast University

Senthil Balaji Girimurugan

Florida Gulf Coast University

Thursday July 31, 2025 9:30am - 9:45am CDT
Strand 11A

Oral presentation, Teaching Methods 2

Subject Teaching Methods
Poster # csv

10:14am CDT

CHMG 1 - Oral Session

Thursday July 31, 2025 10:14am - 10:15am CDT

Strand 11A

Presiding/Moderator

Amy Bruzzichesi

NC State University

Amy Bruzzichesi, MSW, HTR is a therapeutic horticulturist, horticultural therapist, and career social worker with a background in elder care, medical social work, and the nonprofit world. Amy is part of NC Cooperative Extension as the Therapeutic Horticulture Program Manager, sustaining... Read More →

Thursday July 31, 2025 10:14am - 10:15am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener

10:15am CDT

CHMG 1 - Citi-Sci: A Multi-state Gardening Project to Evaluate Plant Preferences and Knowledge Gained from Extension Education

Thursday July 31, 2025 10:15am - 10:30am CDT

Strand 11A

A citizen-science gardening project was conducted in 2024 with 205 participants from Indiana, Iowa, North Carolina, and Tennessee. Participants grew two cultivars of strawberry (Fragaria × ananassa): ‘Elan’, a vigorous white-flowered plant, and ‘Tristan’, a pink-flowered plant with ornamental appeal. The study used a 15-question pre- and posttest format to assess changes in participant confidence related to pest management, personal nutrition, and mental health care. Participants also reported cultivar and plant-type preferences in the post-test. Monthly virtual educational sessions on the assessed topics were delivered by Extension faculty. Only 110 participants completed both the pre- and posttests, enabling evaluation of knowledge gain. An increase in mean scores was measured for 13 questions, suggesting that participants benefited from the educational Extension programming. The greatest improvements were measured in pest management knowledge, with gains ranging from 10% to 19%, whereas questions about methods to reduce stress increased only by 6% to 8%. In the posttest, 76% of participants preferred ‘Tristan’, citing its more attractive appearance, earlier harvest, and better yield compared to ‘Elan’. On average, ‘Tristan’ plants produced their first harvest 49 d after planting, compared to 58 d for ‘Elan’. Notably, willingness-to-pay data indicated that participants valued both cultivars similarly. Our findings demonstrate the positive impact of Extension programming on gardening-related knowledge and highlight the value of collaboration between university researchers, Extension faculty, and stakeholders as citizen scientists.

Speakers

Celina Gomez

Purdue University

Co-authors

Cynthia Haynes

Iowa State University

Karen Mitchell

Purdue University

Melinda Knuth

North Carolina State University

Michael Fidler

Purdue University

Natalie Bumgarner

University of Tennessee

Siria Cardenas

Purdue University

Thursday July 31, 2025 10:15am - 10:30am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Funding Source This activity was funded by Purdue University as part of AgSEED Crossroads funding to support Indiana’s Agriculture and Rural Development.

10:30am CDT

CHMG 1 - East Texas Master Gardener Characteristics, Volunteer Choices, and Willingness to Answer Questions from the Public

Thursday July 31, 2025 10:30am - 10:45am CDT

Strand 11A

East Texas Master Gardener volunteers were asked to participate in an exploratory Qualtrics survey during the fall of 2023. This study examined the demographic characteristics, volunteer engagement choices, and challenges of Master Gardener volunteers in Texas A

Speakers

Jared Barnes

SFASU

Co-authors

Candis Scallan

Stephen F Austin State University

Greg Grant

Stephen F Austin State University

Pat Stephens-Williams

Stephen F Austin State University

Ray Darville

Stephen F. Austin State University

Thursday July 31, 2025 10:30am - 10:45am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Poster # csv

10:45am CDT

CHMG 1 - Free Farmers' Markets for Salt Lake County Seniors

Thursday July 31, 2025 10:45am - 11:00am CDT

Strand 11A

The Utah Commission on Aging defines food insecurity as lack of reliable access to sufficient amounts of affordable and nutritious foods. Seniors experiencing food insecurity are disproportionately low-income and often suffer from chronic health conditions (Hartline-Grafton, 2019) and food insecure older adults with chronic conditions have higher health care costs than their non-food insecure counterparts (Garcia et al., 2018). Food insecurity among low-income seniors is a complex issue because impacted individuals may experience limited mobility and not reside near food stores. Additionally, many low-income seniors must choose between feeding themselves, paying medical bills, and affording household expenses (Utah Food Bank, 2019). The Utah Food Bank reports that about 12% of Utah seniors struggle with hunger (up 45% since 2001) and the number is expected to climb to 8 million by 2050 as the aging population doubles. Salt Lake County (SLCo) Adult and Aging Services published a 2023 Community Needs Assessment which identified the top three of needs of local seniors were healthcare, transportation, and nutrition. The study highlighted government providers must “achieve greater impact through partnerships and innovation”. The free farmers’ markets at senior centers program demonstrates an innovative partnership that couples County government providers with Utah State University Extension (USU Extension) to address food insecurity experienced by low-income seniors. USU Extension utilizes public volunteers to grow and disseminate locally grown produce to urban dwelling seniors through the farmers’ market program. USU Extension Master Gardener (MG) volunteers provide service hours in exchange for horticulture training. In Salt Lake County, MGs are encouraged to grow and donate homegrown produce for distribution at markets. Since 2017, 20 tons of produce has been distributed with an approximate market value of $80,000. 7,500 seniors were served during 135 markets. Benefitting seniors reported that: 97% saved money, 100% increased access to fresh produce, and 100% increased consumption of fresh produce.

Speakers

Katie Wagner

Utah State University

Thursday July 31, 2025 10:45am - 11:00am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Poster # csv

11:00am CDT

CHMG 1 - The Real Truth About Tech Savviness Among Extension Personnel and Volunteers

Thursday July 31, 2025 11:00am - 11:15am CDT

Strand 11A

With an increasing dependence on technology for delivering volunteer training and client programs within Extension, it is essential to assess the tech savviness of both volunteers and paid personnel. Paid personnel often express frustration over volunteers’ lack of technological skill, while volunteer skills can also far surpass that of the personnel’s skill level. These situations can lead to mistrust and missed opportunities for both personnel and volunteers alike. To assess technology skills (tech savviness) among personnel and volunteers, a random sample (n=572) of Extension personnel (agents, staff, AmeriCorps members, and county coordinators) and volunteers (Extension Master Gardeners and 4-H volunteers) were asked to provide subjective assessment of their technology skills as well as that of their counterparts (i.e., volunteers self-assessed their program coordinators, while paid personnel assessed that of their volunteers). Respondents then completed a 10-question technology skills quiz for an objective measure of skills. Questions included keyboard shortcuts, trouble-shooting scenarios, use of computer and social media applications, as well as hardware and basic equipment set-up. Results confirmed that there is a significant difference between actual and perceived volunteer and personnel technology skills, though overall scores reflect a need for continued technology skill-development for both volunteers and personnel.

Speakers

Sheri Dorn

Co-authors

Keri Hobbs

University of Georgia

Thursday July 31, 2025 11:00am - 11:15am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Funding Source Horticultural Research Institute

11:15am CDT

CHMG 1 - What motivates people to become an Extension Master Gardener, and what inspires them to remain?

Thursday July 31, 2025 11:15am - 11:30am CDT

Strand 11A

Why do people pay a significant amount of money to take 50 hours of coursework and give 50 hours of volunteer service to become a certified Extension Master Gardener (EMG)? What is the incentive to remain an EMG? Why do they volunteer for Extension instead of a local hospital or other community organizations? This study answered these questions to enhance Extension educator training on volunteer management and engagement, recruitment, and retention of EMGs. The EMG program director and program manager partnered with a family and consumer science specialist and staff to co-develop the study and collect data. Six focus group interviews with EMGs (n=26) and eight focus group interviews with Extension EMG county coordinators (n=15) were conducted and recorded via Zoom in November 2024. The comments obtained in the focus group sessions were transcribed and coded into themes in each of the combined groups interviewed. Focus group comments revealed information that needed to be and could be addressed immediately. This led to four technical reports containing recommendations for program improvement in recruitment and retention of EMGs directed to Extension administration, the EMG program director and manager, Extension EMG coordinators, and EMGs. In addition, data will be used to formulate questions for a survey to be administered to EMGs in the fall of 2025. In this session, you will learn about the research study, the focus group data collection process, results and recommendations for program improvement, and the necessary steps to continue developing this knowledge.

Speakers

Pam Bennett

State Master Gardener Program Director, Professor, Ohio State University

Co-authors

Anita Armstrong

Ohio State University

James Bates

Ohio State University

Jennifer Andon

Ohio State University

Thursday July 31, 2025 11:15am - 11:30am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Poster # csv

11:30am CDT

CHMG 1 - Accelerated Composting Of Kitchen Scraps Used In Horticultural Substrates

Thursday July 31, 2025 11:30am - 11:45am CDT

Strand 11A

Residential food scraps accounts as a major landfill product that is responsible for 40% of kitchen waste. Reducing these waste products is a goal of EPA by 2030. The objective of this study is to use an accelerated home food scrap composter to encourage residents to reduce waste volume and weight and provide garden compost to produce garden produce and flowers. Two accelerated composters (Lomi and Vego) were evaluated both for their compost soil health, physical and chemical properties after processing kitchen scraps (apples, bread, chicken, coffee, milk, and Irish potatoes). Lomi processed food for 24h only and the Vego composter for 1, 5, and 10 days. Compost volume and weight increased as days of composting increased. Compost health, nutrients, pH, C/N Ratio were suitable for a horticultural growing amendment. Physical components were within normal parameters for a soil substrate. Finer particles were increased with greater days of composting as expected. Plant growth, SPAD readings showed an increase with 5- and 10-days composting. Compost incorporated at 10 % v/v increased petunia biomass. Accelerated composters reduced volume and weight of food scrapes while providing essential plant nutrients.

Speakers

William Dunford

Louisiana State University

Co-authors

Alessandro Holzapfel

Louisiana State University Agricultural Center

Claire Bradley

LSU

Edward Bush

LSU AgCenter

Thursday July 31, 2025 11:30am - 11:45am CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Funding Source Hatch
Funding Option SCRI funded all or part of the research associated with this abstract

11:45am CDT

CHMG 1 - Therapeutic Horticulture Learning in Action: An Update from NC State

Thursday July 31, 2025 11:45am - 12:00pm CDT

Strand 11A

The NC State Extension Gardener - North Carolina Botanical Garden Online Therapeutic Horticulture course partnership has demonstrably achieved significant success in expanding access to affordable, comprehensive training in the field. Since its 2020 inception, this collaboration has successfully introduced over 600 students residing in 45 U.S. states and 19 countries to the practice, establishing itself as a pivotal resource for individuals seeking to integrate nature-based interventions into therapeutic practices. The program's curriculum is thoughtfully designed to guide participants along a continuum, fostering growth from initial interest in the benefits of human-plant interaction to the development of practical proficiency in therapeutic horticulture techniques and program management. A key element of the course's success lies in its robust and adaptable online format, which effectively transcends geographical barriers and accommodates diverse learning styles and schedules. The comprehensive training encompasses foundational horticultural knowledge, an in-depth exploration of the theoretical underpinnings of therapeutic horticulture, and practical strategies for designing and implementing effective plant-based activities tailored to various populations and therapeutic goals. Furthermore, the partnership leverages the combined expertise of experienced professionals, ensuring a well-rounded and evidence-based educational experience. The substantial enrollment figures and broad geographical reach underscore the growing recognition of therapeutic horticulture as a valuable intervention within healthcare, education, and community-based settings. By equipping individuals with the necessary knowledge and skills, this online program is actively contributing to the expansion of qualified practitioners and the wider adoption of therapeutic horticulture practices globally. The positive impact is evidenced not only by the number of students served but also by the anecdotal reports of graduates successfully applying their training to enhance well-being and facilitate positive change in their respective communities. The continued growth and influence of this partnership highlight the transformative potential of accessible and high-quality online education in this increasingly vital field.

Speakers

Amy Bruzzichesi

NC State University

Co-authors

Alta Zhang

NC State University

Emilee Weaver

University of North Carolina at Chapel Hill

Joanna Lelekacs

University of North Carolina at Chapel Hill

Lucy Bradley

NC State University

Sally Haskett

University of North Carolina at Chapel Hill

Sarah Tanke

University of North Carolina at Chapel Hill

Thursday July 31, 2025 11:45am - 12:00pm CDT
Strand 11A

Oral presentation, Consumer Horticulture and Master Gardeners 1

Subject Consumer Horticulture and Master Gardener
Funding Source Project is funded through cost-recovery revenue

1:44pm CDT

FLOR 3 - Oral Session

Thursday July 31, 2025 1:44pm - 1:45pm CDT

Strand 11A

Presiding/Moderator

Juan Quijia Pillajo

The Ohio State University

Thursday July 31, 2025 1:44pm - 1:45pm CDT
Strand 11A

Oral presentation, Floriculture Floriculture 3

Subject Floriculture

1:45pm CDT

FLOR 3 - Substrate pH and Inoculant Amendments Modulate Phosphate-Solubilizing Bacteria Efficacy in French Marigold: Impacts on

Thursday July 31, 2025 1:45pm - 2:00pm CDT

Strand 11A

Calcium phosphate [Ca₃(PO₄)₂] is an nonlabile form of phosphorus (P) commonly found in substrates with a basic pH and it is not available for plant uptake. Phosphate solubilizing bacteria (PSB) are plant-associated microorganisms that can solubilize calcium phosphate by secreting organic acids. PSB inoculation alleviates P deficiency symptoms including leaf purpling, and PSB inoculum can be amended with substances that may improve PSB performance (i.e. glucose). Our goal was to evaluate the efficacy of PSB isolated from the rhizosphere of greenhouse ornamentals (Pantoea trifolii C2B11, Pantoea formicae C8D10, Pantoea sp. C2G6 and Enterobacter soli C4A1) in substrate with pH 6.0 or 6.5, and with an inoculum amended with glucose (10 g·L-1), Luria Bertani (LB) broth (111 mL·L-1), or humic and fulvic acids (20 g·L-1). An experiment was conducted using French marigold 'Durango Yellow' (Tagetes patula) fertilized once per week with 200 mg·L-1 N from a 15N-0P-12.5K-2.9Ca-1.2Mg fertilizer. P was supplemented to the fertilizer solution as Ca3(PO4)2 at 10 mg·L-1 P. Bacillus velezensis was included as a positive control. Digital biomass, Normalized Pigment Chlorophyll Ratio Index (NPCI), Plant Senescence Reflectance Index (PSRI) and canopy hue (color) were measured with the TraitFinder, a digital phenotyping workstation. NPCI and PSRI values from healthy foliage are low but increase under stress. At pH 6.0, all marigolds receiving PSB had increased growth regardless of the inoculum amendments. PSB amended with glucose resulted in marigolds with a lower NPCI than non-inoculated plants. Additionally, PSB-treated marigolds had a higher proportion of green canopy, and a lower proportion of red canopy compared to non-inoculated marigolds when the inoculum was amended with glucose or not amended. At pH 6.5, all PSB resulted in increased marigold growth regardless of inoculum amendments. PSB treated marigolds were healthier than non-inoculated plants, as indicated by their lower NPCI and PSRI values, regardless of the inoculum amendments. Accordingly, PSB treated marigolds had a higher proportion of green canopy and a lower proportion of red canopy compared to non-inoculated marigolds. Bacterial effects were more consistent when inoculum was supplemented with LB. A greater benefit was observed in plants grown at pH 6.5. Microbiome analysis of the rhizosphere showed that inoculation with C2B11, C2G6, and C8D10 increased the relative abundance of the genus Pantoea, and C4A1 enriched the genus Enterobacter. Careful determination of optimal inoculum supplements is key to developing efficient inoculants that promote growth in greenhouse ornamentals.

Speakers

Juan Quijia Pillajo

The Ohio State University

Co-authors

James Altland

USDA-ARS

James Owen

USDA ARS

Laura Chapin

The Ohio State University

Michelle Jones

The Ohio State University

Sachin Naik

The Ohio State University

Thursday July 31, 2025 1:45pm - 2:00pm CDT
Strand 11A

Oral presentation, Floriculture Floriculture 3

Subject Floriculture
Funding Source NIFA AFRI grant 2022-67013-36489

2:00pm CDT

FLOR 3 - Siderophore producing bacteria isolated from the rhizosphere of greenhouse plants enhance plant growth under iron-limiti

Thursday July 31, 2025 2:00pm - 2:15pm CDT

Strand 11A

Supplying adequate iron (Fe) to greenhouse crops is challenging, particularly for iron-sensitive plants grown in soilless substrates under alkaline conditions. High pH levels reduce Fe bioavailability by promoting the formation of insoluble iron hydroxide (Fe(OH)₃), which limits plant uptake. Plant growth-promoting bacteria (PGPB) enhance plant growth and stress tolerance through diverse mechanisms, including siderophore production. Siderophores are small molecules that have a high affinity for metal ions like ferric iron (Fe³⁺). Once the siderophore chelates iron, the complex is soluble, and plant roots can readily absorb it. This study identified siderophore producing bacteria (SPB) capable of enhancing plant growth under Fe-limiting conditions. A rhizosphere bacterial collection from greenhouse plants was screened for siderophore production using the chrome azurol S (CAS) assay. Genomic analysis of 12 isolates identified in the CAS assay revealed diverse siderophore-related genes and other plant growth-promoting traits. Five of the isolates (C2G2, C5A12, C6E3, C8G7, and C10A8) were identified as strong candidates based on their siderophore-related genes and Fe uptake pathways. A ferrozine-based assay confirmed Fe solubilization in a modified Hoagland’s solution containing goethite (Fe³⁺O(OH)) as an insoluble Fe source, with bacterial treatments yielding 0.57 mg Fe L⁻¹ versus 0 mg Fe L⁻¹ in controls (no bacteria). Subsequent in planta experiments evaluated the impact of SPB on French marigold ‘Durango Yellow’ (Tagetes patula) growth in hydroponic systems under Fe-limiting conditions. French marigold proved to be a good model plant for this screening system. Digital phenotyping showed that plants inoculated with isolates C5A12, C8G7, or C10A8 had 53.0%, 45.7%, or 50.3% more green leaf tissue, respectively, compared to untreated control plants. Additionally, treated plants had increased root biomass. These findings demonstrate the potential of SPB to enhance Fe availability and plant growth under iron-limiting conditions and offer a novel strategy for improving greenhouse crop production. The incorporation of SPB into greenhouse practices may benefit Fe-sensitive crops or systems where pH fluctuations reduce Fe availability, ultimately improving crop quality and sustainability.

Speakers

Laura Chapin

The Ohio State University

Co-authors

Michelle Jones

The Ohio State University

Sachin Naik

The Ohio State University

Thursday July 31, 2025 2:00pm - 2:15pm CDT
Strand 11A

Oral presentation, Floriculture Floriculture 3

Subject Floriculture
Funding Source NIFA Agriculture and Food Research Initiative, 2022-67013-36489

2:15pm CDT

FLOR 3 - Wood Component Type And Peat Inclusion Rate Impact Pre-Plant Substrate pH Across Four Dolomitic Lime Amendment Rates.

Thursday July 31, 2025 2:15pm - 2:30pm CDT

Strand 11A

Increased interest in peat-alternative substrates has contributed to the development of both regional and global wood substrates. Utilizing different manufacturing equipment to produce wood fiber components allows producers to modify wood fibers/inputs through chipping, milling, heat, pressure, or various combinations, to alter physical properties and yield suitable material for horticulture use. Commercial substrates available for plant production include peat-reduced formulas with various percentages (by volume) of wood fiber. Current lime amendment suggestions to bring substrates into the optimal pH range for plant growth are based on peat as the main component. Wood fiber has variable initial pH across manufactured type and reacts differently to lime amendments compared to peat. To aid in the understanding of lime amendments to wood fiber substrate blends, this study was designed to measure the pre-plant pH response over time of substrates influenced by wood component type, peat inclusion percentage, and dolomitic lime amendment rate. Three types of manufactured wood substrates (hammermilled, screw-extruded, and disc refined) were individually blended with Sphagnum peat at 20% increments (20, 40, 60, 80, and 100%). Each substrate was amended with 0, 4, 8, or 12 lbs/yd3 dolomitic lime and incubated in plastic bags to measure pH change at 0, 1, 3, 5, 7, 14, 21, and 28 days after blending. Resulting pH values indicate dolomitic lime amendment rates will need to be adjusted based on peat:wood volume ratios. Wood fiber exhibited a higher initial pH than Sphagnum peat and within blends, as wood fiber rate increased, pH increased across all lime rates. Dolomitic lime amendments should be closely monitored at 40% volume or more wood fiber. Moderate pH differences were measured between manufactured wood fiber type within the same peat:wood volume ratio and lime rate, emphasizing interchangeability of wood component type.

Speakers

Hauk Boyes

North Carolina State University

Co-authors

Brian Jackson

North Carolina State University

Thursday July 31, 2025 2:15pm - 2:30pm CDT
Strand 11A

Oral presentation, Floriculture Floriculture 3

Subject Floriculture
Funding Source American Floral Endowment (AFE)

2:30pm CDT

FLOR 3 - Investigating applications of black soldier fly larvae (Hermetia illucens) frass in ornamental horticultural production

Thursday July 31, 2025 2:30pm - 2:45pm CDT

Strand 11A

Frass is the left-over substrate produced from mass rearing insects as food and feed. Black soldier fly (Hermetia illucens) larvae frass has become a popular option for vegetable production as a potential fertilizer and peat replacement. Controlled environment propagation of ornamental crops requires large amounts of peat, therefore researching alternative substrates has a rising interest for growers. Pansies (Viola x wittrockiana), Marigold ‘Inca II’(Tagetes erecta), and Marigold ‘Safari’(Tagetes patula) were grown in growth chambers to evaluate the incorporation of frass into peat based substrates for ornamental production: 3 treatments from previous studies (BSF 10, 20, and 30%), 1 treatment included to assess the impact of leaching on frass (BSF 40-), and a 100% peat control (CP 100%). Pansies grown in the BSF treatments of were statistically comparable to the control in all parameters except, root weight. Pansy root weight was significantly higher in the treated BSF 40- treatment. BSF 40% produced the lowest values in all crops and parameters, except for Marigold ‘Inca’ root weight, where only BSF 40- was significantly higher. BSF 40- was significantly greater or equal to the control in all crops and parameters, except for Marigold ‘Safari’ plant size and root weight. Chlorophyll concentrations were statistically comparable across all treatment and control in all crops. Past research and this study generally indicate that at large concentrations, like 40%, frass can have negative outcomes for crop production in peat based substrates. However, due to the success of our leached treatment, BSF 40-, it seems frass can be utilized at larger concentrations, but additional alterations may be required before mixing into growing medias and substrates. Additionally, certain crops appear to have more neutral and positive reactions to frass incorporation. Engaging efforts to target ideal crops will improve the application and practicality of this research.

Speakers

Maria Chavez

New Mexico State University

Co-authors

Jennifer Bousselot

Colorado State University

Joshua Craver

Colorado State University

Thursday July 31, 2025 2:30pm - 2:45pm CDT
Strand 11A

Oral presentation, Floriculture Floriculture 3

Subject Floriculture
Funding Source CSU Spur

2:45pm CDT

FLOR 3 - Using Plant Growth-Promoting Rhizobacteria to Enhance Plant Growth with the Ferrous Sulfate Bridge Method of Reducing Ph

Thursday July 31, 2025 2:45pm - 3:00pm CDT

Strand 11A

Phosphorus (P) is an essential macronutrient required for plant growth. In fertilizers used for soilless substrates, P is in the form of phosphate and is readily leached from containers leading to environmental contamination. The FeSO4 bridge method has been proposed to reduce P losses by forming insoluble iron-phosphate complexes that retain P within the substrate, but reduced bioavailability may limit plant growth. The aim of this research was to evaluate the FeSO4 bridge method in combination with inoculation of the substrate with phosphate-solubilizing bacteria (PSB) and siderophore-producing bacteria (SPB) to gradually release P for plant uptake. An experiment was conducted to evaluate the growth of marigolds ‘Durango Yellow’ (Tagetes patula) using a substrate composed of 80% peat and 20% perlite by volume, with substrate either amended or not amended with 3.0 kg·m-3 FeSO4·7H2O. After transplanting, plants received 100 mg·L-1 N from 15N-2.2P-12.5K-2.9Ca-1.2Mg Jack’s Professional water-soluble fertilizer as the P source for two weeks to promote the formation of iron-phosphate complexes. Additionally, two bacterial application strategies were evaluated: one starting from transplanting and another applied when P deficiency symptoms appear, with three weekly inoculations each. The bacterial treatments included: a control without bacterial inoculation; three PSB strains, Bacillus megaterium (C3F10), Pantoea rwandensis (C3A8), and Pseudomonas sp. (C6E7); one SPB strain Pseudomonas soli (C10A8); and a commercial inoculum of Bacillus velezensis (from the biostimulant LalRise Vita, Lallemand, Inc). Plants were grown under controlled greenhouse conditions, with weekly measurements of spectral variables and morphological parameters using the TraitFinder digital phenotyping system. Leachate was collected using the pour-through method and analyzed for P concentrations using ion chromatography. The results confirmed that the FeSO4 bridge method formed iron-phosphate complexes, reducing P leaching when amending the substrate with 3.0 kg·m-3 FeSO4·7H2O compared to non-amended substrate. Visual differences in plant growth were observed among treatments, with better outcomes when bacterial inoculation started at transplanting. In contrast, plants that received bacterial treatment after symptoms appeared could not recover, showing significantly reduced visual quality. Among the bacterial treatments, Pseudomonas soli (C10A8) promoted the highest biomass accumulation and spectral variables such as hue and green leaf index (GLI) indicated improved visual quality compared to the control (no bacteria) and other bacterial strains. These findings demonstrated that amending soilless substrates with FeSO4, combined with bacteria like Pseudomonas soli (C10A8), enhances P retention while promoting plant growth. This method offers growers a practical approach to reducing environmental impact while maintaining crop quality.

Speakers

Alexandra Espinoza

The Ohio State University

Co-authors

James Altland

USDA-ARS

Michelle Jones

The Ohio State University

Thursday July 31, 2025 2:45pm - 3:00pm CDT
Strand 11A

Oral presentation, Floriculture Floriculture 3

Subject Floriculture
Poster # csv

3:59pm CDT

FRBR 2 - Oral Session

Thursday July 31, 2025 3:59pm - 4:00pm CDT

Strand 11A

Presiding/Moderator

Margaret Worthington

University of Arkansas

Thursday July 31, 2025 3:59pm - 4:00pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding

4:00pm CDT

FRBR 2 - Ploidy Induction of Triploid Interspecific Hybrid Blueberries

Thursday July 31, 2025 4:00pm - 4:15pm CDT

Strand 11A

Blueberry is a high value fruit crop and there is an increased demand for its cultivation and consumption all over the world. The blueberries are grown in diverse regions with varied weather, soil, biotic and abiotic stress limiting their yield. Interspecific hybridization plays a significant role in broadening the genetic base of blueberries that subsequently helps in developing improved cultivars adapted to specific regions. The genetic diversity for cultivated rabbiteye (RE) (2n=6x=72) blueberries is very narrow. Introgression from wild and other cultivated species would provide beneficial diversity for RE blueberries. Vaccinium elliottii (2n=2x=24) is an early flowering, tall and highly deciduous wild blueberry with small black fruits. Like RE, it is adapted to a wide range of soil types in the southeastern United States. On the other hand, southern highbush is a cultivated tetraploid (2n=4x=48) with high fruit quality but requires intensive soil amendment. To broaden the genetic base of blueberry breeding, interspecific crosses were made between three southern highbush breeding lines and V. elliottii. The success of these crosses was challenging due to strong triploid block from heteroploid crosses. Out of 422 pollination events only 8 triploid seedlings were produced, and their ploidy level was confirmed by flowcytometric analysis. Three seedlings were confirmed to be triploids (3x) however, it is expected that triploids are sterile. Seedlings of the triploids were established in tissue culture and chromosome doubling of these triploid hybrids was carried out to improve their crossing efficiency with cultivated blueberries. The shoots produced through tissue culture were treated with 0.02% colchicine for 48 hours and transferred to woody plant medium (WPM). Synthetic hexaploid hybrids produced from this study will be cross compatible with RE blueberries. These synthetic hexaploid hybrids will bridge the ploidy gap among diploid, tetraploid and hexaploid blueberry species.

Speakers

Sindoora Nalajala

University of Georgia

Co-authors

Peggy Ozias-Akins

University of Georgia

Ye Chu

University of Georgia

Thursday July 31, 2025 4:00pm - 4:15pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Funding Source Georgia Blueberry Commission

4:15pm CDT

FRBR 2 - Cold Hardiness Variation in Vitis vinifera × Vitis riparia Hybrids: Genetic and Environmental Influences on Low Temperature Exotherm Values

Thursday July 31, 2025 4:15pm - 4:30pm CDT

Strand 11A

Grapevine cold hardiness is a critical trait that determines the geographical distribution and winter survival of cultivars, thus a key consideration for viticulture in regions with severe winter conditions. This study investigated the cold hardiness of 312 Vitis riparia F1 hybrids, using differential thermal analysis (DTA) and survival assessments at 4°C over seven and 28 days. The DTA analyses to identify significant changes in progeny lethal temperature exotherm (LTE) values with a wide range of LTE values from -24.3°C to -12.3°C observed after 28 days of cold acclimation. The mean LTE value improved from -16.8°C after seven days to -18.6°C after 28 days with 80.2% of progenies showing significant decreases in LTE values. Progenies were divided into five groups based on cold hardiness: very cold hardy, cold hardy, moderately hardy, susceptible, and very susceptible. Principal component analysis (PCA) demonstrated clear separation among the five cold hardiness groups, with PC1 accounting for 71% of the variance. This study provides valuable insights into the genetic basis of cold hardiness in V. riparia progenies, offering critical information for grape breeding programs aimed at developing cold-resistant cultivars. The identification of highly cold-hardy progenies and the understanding of their genetic diversity will aid in selecting parent plants for breeding, ultimately improving grape production in cold regions.

Speakers

Harlene HattermanValenti

NDSU

Co-authors

Hava Delavar

North Dakota State University

Thursday July 31, 2025 4:15pm - 4:30pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Funding Source VitisGen 3
Funding Option SCRI funded all or part of the research associated with this abstract

4:30pm CDT

FRBR 2 - Linkage Mapping and Genomic Insights in Vitis x Muscadinia Hybrids

Thursday July 31, 2025 4:30pm - 4:45pm CDT

Strand 11A

Combining muscadine (M. rotundifolia) with bunch grapes (V. vinifera) addresses the challenges faced by each species. Muscadines provide strong disease resistance and adaptability to the southeastern U.S climate but lack key fruit quality traits such as seedlessness and crisp texture. In contrast, V. vinifera, produces high-quality fruit but is highly susceptible to diseases like Pierce’s disease and powdery mildew. Hybridization between the two aims to retain the desirable fruit characteristics of V. vinifera while incorporating the resilience of muscadines. Understanding the genetic basis of key agronomic traits in Vitis × Muscadinia (V × M) hybrids is essential for introgressing valuable traits such as seedlessness, disease resistance, and flavor into breeding populations. This study aimed to develop a high-density genetic linkage map to investigate the inheritance of seedlessness, sterility, and recombination patterns in wide hybrids. The mapping population was derived from a cross between AM-116, a seeded Muscadinia rotundifolia selection, and JB15-43-N0-25, a seedless V × M hybrid. Phenotypic evaluations of traits such as flower sex, winter injury, berry size, berry, color, yield, seedlessness, cluster architecture, and vigor were collected and integrated with genotypic data to create a linkage map and identify quantitative trait loci for these traits. RhAmpSeq genotyping was initially used as the primary method to genotype the population and assess recombination frequency across homeologous and homologous chromosome regions. However, because rhAmpSeq markers were designed using Vitis genomes without incorporating Muscadinia, marker coverage in Muscadinia genomic regions was limited. To overcome this limitation, SkimSeq whole-genome sequencing was later employed to construct a high-density linkage map. Principal Component Analysis (PCA) of genomic data revealed that individuals positioned closer to the V × M parent (JB15-43-N0-25) had a higher proportion of Vitis ancestry and an increased number of homeologous chromosomes. This pattern suggests that structural genomic incompatibilities affecting segregation distortion and recombination rates may result in reduced recombination in homeologous regions in V × M hybrids. These findings provide new insights into the genetic mechanisms governing sterility, recombination, and trait introgression in Vitis × Muscadinia hybrids, contributing to the development of breeding strategies aimed at integrating desirable traits across subgenera. Understanding these factors is crucial for overcoming genetic barriers in interspecific breeding and optimizing hybrid vigor for commercial muscadine grape production.

Speakers

Isabella Vaughn

University of Arkansas

Co-authors

Carmen Johns

University of Arkansas

Cheng Zou

Cornell University

Dustin Wilkerson

Cornell University

Lacy Nelson

University of Arkansas

Margaret Worthington

University of Arkansas

Qi Sun

Cornell University

Thursday July 31, 2025 4:30pm - 4:45pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Funding Source This work was funded by VitisGen3, which was provided by Specialty Crop Research Initiative Competitive Grant, Award No. 2022-51181-38240, of the USDA National Institute of Food and Agriculture.
Funding Option SCRI funded all or part of the research associated with this abstract

4:45pm CDT

FRBR 2 - Gene Expression Analysis in the Linkage Group 7 Eastern Filbert Blight Resistance Region in Hazelnut

Thursday July 31, 2025 4:45pm - 5:00pm CDT

Strand 11A

Eastern filbert blight (EFB) disease caused by the fungal pathogen Anisogramma anomala (Peck) E. Müller is a major threat to Oregon’s hazelnut (Corylus avellana) industry. Although cultivars with ‘Gasaway’ resistance have sustained the Oregon hazelnut industry, ‘Jefferson’ and ‘McDonald’ trees protected by a dominant allele for resistance from ‘Gasaway’ have shown small cankers when under high disease pressure for several years. In late 2023, a few orchards in the northern Willamette Valley reported infections on ‘Gasaway’ protected trees with highly aggressive cankers and fully developed stromata, indicating the ability to reproduce on resistant varieties and signaling the breakdown of ‘Gasaway’ resistance in Oregon. The OSU hazelnut breeding program has conducted extensive EFB screening efforts on curated germplasm, and more than 30 sources of EFB resistance have been assigned to a linkage group (LG) using SSR loci and disease score correlation analyses. Fine mapping of the LG7 resistance region using the ‘Ratoli’ and OSU 1166.123 backgrounds with simple sequence repeat (SSR) and PCR allele competitive extension (PACE) SNP genotyping assays narrowed the resistance region. However, gene expression profiling is desired to further elucidate which candidate genes overlap between fine-mapping efforts and gene expression to refine marker development efforts for LG7 resistance. The objective of this study was to identify differentially expressed genes (DEGs) in six hazelnut genotypes (‘Ennis’, OSU 1026.073, OSU 1166.123, OSU 541.147, ‘Ratoli’, and ‘Sacajawea’) at different stages of EFB infection. Layered and grafted trees with ‘McDonald’ rootstocks were grown in 3L pots at the OSU West Greenhouses in Corvallis, OR in spring 2023. Inoculations were conducted in an outdoor container pad and new shoot tips with at least two true leaves were spray inoculated with a spore suspension (1x106 spores·mL-1) until run-off. Apical shoots (2-3 internodes) from four biological replicates were collected at 0, 12, 24, 48, 72, 96, 168, and 240 hours post-inoculation, with the addition of two biological mocks sprayed with deionized water. Total RNA was extracted and sequenced using a BRB-seq library prep for the Illumina NovaSeq X Plus platform. Detailed analyses of differentially expressed genes between susceptible and resistant genotypes during the initial stages of EFB infection will be discussed. The results of this study will provide valuable insights into the molecular resistance of hazelnut to EFB, aid marker development for breeding EFB-resistant cultivars, and facilitate the pyramiding of R-genes in a single clonal selection for more durable resistance.

Speakers

Rion Mooneyham

Oregon State University

Co-authors

Gaurab Bhattarai

Oregon State University

Jacob Snelling

Oregon State University

Shawn Mehlenbacher

Oregon State University

Thursday July 31, 2025 4:45pm - 5:00pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Poster # csv

5:00pm CDT

FRBR 2 - Genetic Dissection of Resistance to Peach Fungal Gummosis: Detection and Validation of Loci Originating from Almond and Peach Germplasm

Thursday July 31, 2025 5:00pm - 5:15pm CDT

Strand 11A

Peach fungal gummosis (PFG), caused by fungal pathogens in the Botryosphaeriaceae family, including Botryosphaeria dothidea, Lasiodiplodia theobromae, and Diplodia seriata. This disease is a major threat to Prunus production worldwide. The initial symptoms often remain latent until trees are exposed to stress, at which point it can lead to substantial yield losses and even tree mortality. Given the lack of curative fungicide options and the difficulty of managing prolonged latent infections, genetic resistance has become a central focus for integrated PFG management strategies. A key breakthrough in this effort was the identification of Botd8, a major resistance locus derived from the almond cultivar ‘Tardy Nonpareil.’ Mapped to linkage group 8, Botd8 confers dominant resistance to B. dothidea and co-segregates with the red leaf locus (Gr). Its resistance effect was validated in multiple environments and under different inoculation methods, including field, trellis, and wound inoculation. Further validation using detached stem and leaf assays confirmed that genotypes homozygous or heterozygous carrying Botd8 exhibited significantly reduced lesion development following inoculations with B. dothidea and D. seriata. However, Botd8 was not effective against L. theobromae, underscoring the need for additional resistance sources. The strong correlation between detached stem assay results and field ratings also demonstrated the utility of these rapid, non-destructive screening tools in breeding programs. To expand resistance options beyond almond-derived sources, a recent study focused on the low-chill peach landrace ‘Okinawa’. A segregating F1 population from ‘Okinawa’ × (‘Flordaguard’ × PI91459) was phenotyped for disease severity and genotyped via Genotyping-by-Sequencing. QTL analysis revealed a novel resistance locus on linkage group 6, distinct from Botd8. This QTL consistently explained 29–41% of the phenotypic variation across two years, suggesting a polygenic basis for resistance in peach. Notably, the Botd8 haplotype was common in high-chill cultivars but absent in low-chill germplasm, positioning ‘Okinawa’ as a valuable resistance source for subtropical breeding efforts. Collectively, these studies establish a comprehensive framework for developing PFG-resistant peach cultivars

Speakers

Daniel Mancero

UNIVERSIDAD AGRARIA DEL ECUADOR

Fruit researcher with experience in multidisciplinary projects for plant protection and plant breeding

Co-authors

Gabriel Matsumoto

University of Florida

Jose Chaparro

University of Florida

Phillip Harmon

University of Florida

Thursday July 31, 2025 5:00pm - 5:15pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Poster # csv

5:15pm CDT

FRBR 2 - Pedigree analysis of rabbiteye blueberry (Vaccinium virgatum Aiton) indicates limited genetic diversity

Thursday July 31, 2025 5:15pm - 5:30pm CDT

Strand 11A

As a native species in the southeastern U.S., rabbiteye blueberry (Vaccinium virgatum Aiton) is known for its resilience to environmental stresses and adaptability to various soil types. Rabbiteye was the dominant species grown in the southern U.S. before the rise of southern highbush blueberries (V. corymbosum L. interspecific hybrids). Compared to southern highbush, rabbiteye cultivars are often perceived as seedy and have thick skin. Limited genetic diversity, compounded by repeated use of elite parents and decreased breeding efforts, poses challenges for rabbiteye improvement. To facilitate more efficient rabbiteye breeding in the future, this study aims to assess the genetic diversity of rabbiteye cultivars through pedigree analysis and evaluate the impact of interspecific hybridization on modern cultivars. The pedigree data of 180 rabbiteye blueberry accessions were analyzed to calculate inbreeding coefficients, coefficients of coancestry and the genetic contribution of founders. Five founders ‘Myers’, ‘Black Giant’, ‘Ethel’, ‘Clara’, and ‘W4’, collectively account for a minimum of 73% of the genetic composition of rabbiteye cultivars. The level of interspecific hybridization has been limited in rabbiteye breeding, with V. corymbosum contributing 3% of the genetic composition of rabbiteye cultivars and 1% from other species such as V. constablaei and V. darrowii. The narrow genetic base and repeated use of common parents led to an increase in inbreeding coefficients, from an average of less than 0.0002 before 1980 to 0.014 in the 2000s. In the future, it would be valuable to increase the use of exotic materials from other species or within the rabbiteye germplasm to broaden the genetic base while introducing valuable alleles. Further evaluation of population structure with genomic information is needed to validate pedigree information and provide a more accurate assessment of the genetic diversity and population structure.

Speakers

Sushan Ru

Auburn University

Co-authors

Craig Hardner

University of Queensland

Dorrie Main

Washington State University

Juliet Chu

University of Georgia

Roohollah Abdolshahi

Auburn University

Sook Jung

Washington State University

Thursday July 31, 2025 5:15pm - 5:30pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Funding Source This work is supported by the Specialty Crop Research Initiative project award no. 2022-51181-38449 from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.
Funding Option SCRI funded all or part of the research associated with this abstract

5:30pm CDT

FRBR 2 - Insights from Chromosome Painting in wide Vitis x Muscadinia Hybrids

Thursday July 31, 2025 5:30pm - 5:45pm CDT

Strand 11A

The development of Vitis × Muscadinia (V x M) wide hybrids, combining the disease resistance of muscadines (M. rotundifolia) with the berry quality attributes of V. vinifera grapes has be en a longstanding ambition of breeders. Stenospermocarpic seedless muscadine hybrids and wine grapes carrying powdery and downy mildew resistance introgressed from muscadines have been developed using classical techniques without the assistance of molecular tools through sustained effort over a century. However, progress has been impeded by differences in chromosome number (Vitis=38 chromosomes and Muscadinia=40 chromosomes) and genetic distance between the subgenera. A major objective of the new Vitis x Muscadinia Specialty Crop Research Initiative project is to develop and deploy new genotyping platforms and chromosome painting visualization tools to help grape and muscadine breeders track introgressed chromosomal regions in wide hybrids and accelerate trait discovery and cultivar development in new V x M hybrids. In order to develop a chromosome-painting visualization tool for V x M hybrids, we first conducted a large-scale population diversity analysis using historical data from the rhAmpSeq Vitis core panel. Structure analysis was performed to identify individuals belonging to Muscadinia and five additional subpopulations within subgenus Vitis. Approximately 33,000 marker haplotypes were identified as unique to Muscadinia and 671,000 haplotypes were identified as present only in Vitis. This haplotype information was used to create automated chromosome painting visualizations of introgressed segments in historical and modern V x M hybrids. These visualizations allow us to identify which Vitis-type hybrids carry muscadine introgressions in known resistance loci on chromosomes 12 (Run1/Rpv1), 18 (Run2/Rpv2), and 14 (Ren5) and which Muscadinia-type hybrids have introgressions associated with stenospermocarpy and other fruit-quality alleles from Vitis. This information will assist grape and muscadine breeders in planning crosses and discovering new disease resistance and fruit quality alleles. In the coming months, we intend to extend this strategy to a new low-cost DArTag genotyping panel that has been designed to amplify polymorphic markers in both subgenera. Breeders will then be able to rapidly assess which chromosomal regions and major-effect fruit quality and disease resistance alleles are present in a homozygous or heterozygous state in all new V × M hybrids.

Speakers

Margaret Worthington

University of Arkansas

Co-authors

Cheng Zou

Cornell University

Dustin Wilkerson

Cornell University

Isabella Vaughn

University of Arkansas

Lance Cadle-Davidson

USDA-ARS

Qi Sun

Cornell University

Thursday July 31, 2025 5:30pm - 5:45pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Funding Source USDA NIFA Award # 2024-51181-43236
Funding Option SCRI funded all or part of the research associated with this abstract

5:45pm CDT

FRBR 2 - Finding Gene Locations Influencing Citrus Leaf Morphology Using Genome Wide Association

Thursday July 31, 2025 5:45pm - 6:00pm CDT

Strand 11A

Citrus leaves exhibit remarkable morphological diversity, yet the genetic underpinnings of this variation remain poorly understood. In this study, we investigated the genetic architecture controlling citrus leaf shape by performing genome-wide association studies (GWAS) on over 3,000 digitized leaves collected from 150 citrus varieties across two years (2021 and 2022). Using a 50K SNP Axiom array, we identified consistent genomic regions on chromosomes 2, 3, 5, and 7 that were significantly associated with leaf length, width, and area. Linkage disequilibrium patterns within these regions revealed variability, and gene ontology enrichment indicated that genes involved in cell division, photosynthesis, and transcriptional regulation are overrepresented. Our results highlight the strong and heritable basis of leaf morphology in citrus and suggest that regulatory mechanisms play a major role in shaping these traits. This work provides key insights into the genetic control of leaf form and has potential implications for citrus breeding and functional genomics.

Speakers

Ryan Traband

UC Riverside

Co-authors

Xuesong Wang

UC Riverside

Zhenyu Jia

UC Riverside

Thursday July 31, 2025 5:45pm - 6:00pm CDT
Strand 11A

Oral presentation, Fruit Breeding 2

Subject Fruit Breeding
Poster # csv

7:59am CDT

ORGH 3 - Oral Session

Friday August 1, 2025 7:59am - 8:00am CDT

Strand 11A

Presiding/Moderator

Moriah Bilenky

Purdue University

Friday August 1, 2025 7:59am - 8:00am CDT
Strand 11A

Oral presentation, Organic Horticulture 3

Subject Organic

8:00am CDT

ORGH 3 - To Roll or not to roll: for sunn hemp that is not such an easy question

Friday August 1, 2025 8:00am - 8:15am CDT

Strand 11A

Despite its challenges, non-chemical, reduced tillage vegetable production is of continued interest among researchers and growers as a way to improve soil health. Primarily success in this production method has been use of high biomass cover crops such as cereal rye terminated with a roller crimper. However alternative cover crops should be explored to diversify reduced tillage systems and to improve nitrogen synchrony. Sunn hemp (Crotelaria juncea) is a high biomass producing legume with potential to achieve weed suppression while reducing nitrogen immobilization in non-chemical, no-till vegetable production. A two-year study was conducted at the Meigs Horticulture Facility (Meigs) in Lafayette IN to assess the potential of sunn hemp as a cover crop suitable for rolling in a non-chemical, no-till vegetable production system. At Meigs roll success of three sunn hemp rolling dates was evaluated. Followed by Swiss chard production. Sunn hemp was rolled with and I and J roller crimper 60, 70, and 80 days after seeding. Prior to rolling sunn hemp height, above ground biomass (sunn hemp and weed), and roll success was measured 4 weeks after rolling by collecting terminated (senesced) and non- terminated (non- senesced) sunn hemp from 0.25m2 quadrats. Roll success was most related to sunnhemp height and biomass at time of rolling (R2 = 0.76 P < 0.01 ,0.68 P =0.15). In year one rolling was only successful 80 days after seeding, however in in year two rolling was successful at all seeding dates. More research is needed to understand mechanisms contributing to sunn hemp rolling success.

Speakers

Moriah Bilenky

Purdue University

Friday August 1, 2025 8:00am - 8:15am CDT
Strand 11A

Oral presentation, Organic Horticulture 3

Subject Organic
Poster # csv

8:15am CDT

ORGH 3 - Organic High Tunnel and Field Comparison in Specialty Hybrid Tomato: Impacts on Yield, Nutrition, and Marketability Characteristics

Friday August 1, 2025 8:15am - 8:30am CDT

Strand 11A

Tomatoes (Solanum lycopersicum L.) are the largest vegetable crop in the US by dollar value and represent a significant source of income for organic growers in the southeast. High tunnels allow growers to capture more profitable early markets, and the protection they offer provides additional benefits such as extended growing seasons and reduced leaf wetness/foliar disease. Most research on organic high tunnel tomatoes to date focuses on heirloom varieties due to their popularity among organic growers. However, advances in plant breeding in recent decades have yielded hybrids that combine the desirable culinary and aesthetic characteristics of heirlooms with the superior vigor and disease resistance of modern genetics. The objective of this study was to compare the performance and characteristics of such specialty hybrids under organic high tunnel, and organic and conventional field conditions in the Georgia Piedmont region. Two indeterminate cultivars were chosen for this project: ‘Estiva’, a mediterranean variety noted for setting fruit under high temperatures; and ‘Tomimaru Muchoo’, a Japanese pink slicer with thin skin and low acidity. Transplants of both varieties were grown under organic greenhouse conditions for several weeks before planting in organic field, organic high tunnel, or conventional field plasticulture systems. Data loggers were placed in each site to record temperature, relative humidity, PAR, and soil moisture. Fruits were harvested once per week and sorted by USDA marketability standards. Both total and marketable yield were recorded for each plot, as well as disease, pest, and physiological disorder damage. Subsampled fruits from each plot were measured for dimensions, mass, and qualitative aesthetic rating. Fruit and aboveground biomass samples from each plot were harvested, dried, and ground, then analyzed for elemental nutrient content. Soil samples were also taken from each plot prior to planting and after termination for nutrient analysis, pH, and organic matter. In 2023, the highest marketable yields were from the organic high tunnel, with ‘Estiva’ and ‘Tomimaru’ averaging 15491 and 15992 lb/A (FW), respectively; while the conventional field performed better in 2024, with average yields of 11807 (‘Estiva’) and 11611 lb/A (‘Tomimaru’). In 2024, ‘Estiva’ had substantial losses in the high tunnel due to blossom end rot, with 30% of the harvest being marketable as opposed to the 53% obtained from ‘Tomimaru’. These results suggest that under optimal conditions, organic growers can achieve similar yields of high-quality tomatoes to their conventional counterparts through proper application of high tunnels and superior varieties.

Speakers

Micah Jones

University of Georgia

Co-authors

Anish Malladi

University of Georgia

Dorcas Franklin

University of Georgia

Kate Cassity-Duffey

University of Georgia

Friday August 1, 2025 8:15am - 8:30am CDT
Strand 11A

Oral presentation, Organic Horticulture 3

Subject Organic
Poster # csv

8:30am CDT

ORGH 3 - Aerate organic nutrient film technique (NFT) reservoir tank, not for the crop but for microorganisms

Friday August 1, 2025 8:30am - 8:45am CDT

Strand 11A

Organic lettuce production in hydroponic systems often yields less than conventional production. A previous study from the lab found that organic nutrient film technique (NFT) system with Pre-Empt organic fertilizer contained high concentrations of nitrite ions, which likely induce stress and resulted in lower lettuce yield. To address this toxicity, we conducted a series of studies investigating the effect of reservoir aeration, with the hypothesis that aeration would enhance microbial mineralization of organic nitrogen and reduce the concentrations of phytotoxic compounds such as nitrite and ammonium. In the first study, we aerated NFT reservoir tanks with 15.9 mL/L (2 oz/gal) Pre-Empt organic fertilizer. Aeration increased dissolved oxygen (from 6.4 to 7.8 mg/L) and decreased the ratio of nitrite-nitrogen to nitrate-nitrogen (from 1.1 to 0.2) but did not affect ammonium. As a result, aeration increased yield of ‘Casey’ lettuce by 2.6 times. In the second study, aeration did not increase lettuce growth when the concentration of Pre-Empt fertilizer decreased to 10.6 mL/L (1.4 oz/gal). Furthermore, in the third study, we found cultivar-specific response to the aeration of organic fertilizer. These results suggested that aeration can enhance mineralization of organic nitrogen, reduce root-zone nitrite toxicity and increase lettuce yield at high fertilizer rates and potentially depending on cultivar.

Speakers

Jun Liu

Texas A

Co-authors

Genhua Niu

Texas A

Joseph G. Masabni

Texas A

Friday August 1, 2025 8:30am - 8:45am CDT
Strand 11A

Oral presentation, Organic Horticulture 3

Subject Organic
Funding Source USDA NIFA hatch project TEX07726

8:45am CDT

ORGH 3 - Paving the Way to Certified Naturally Grown Certification

Friday August 1, 2025 8:45am - 9:00am CDT

Strand 11A

As environmental concerns grow, the horticultural sector is increasingly encouraged to adopt sustainable production practices. Certified Naturally Grown (CNG), established in 2002, offers a peer-reviewed certification rooted in organic principles and aims to foster a strong community network for small-scale producers. This research documents the process of certifying previously unmanaged farmland through the CNG program, offering research-based insights for growers considering certification. The project began with the revitalization of an overgrown, neglected field, focusing first on soil improvement and field preparation to support sustainable crop production. To build soil health and fertility, we planted both summer and fall/winter cover crop mixtures, which helped improve nutrient cycling and restore organic matter. In addition to soil improvement, we developed an integrated pest management (IPM) protocol tailored to our production system and selected OMRI-listed products to meet fertilization, pest, and disease control needs in compliance with CNG standards. To support certification, we also established a record-keeping system to document field activities, input usage, and compliance measures. Finally, we created postharvest handling protocols aligned with CNG principles to help ensure both food safety and product quality from field to market. Soil testing has shown an improvement in soil organic matter, plant-available soil nutrients, and an increase in soil microbial biomass. These gains reflect an improvement in overall soil health and provide a strong foundation for sustainable crop production. Ultimately, this project highlights the planning and steps required for successful CNG certification. The educational tools we create will serve as a guide for producers transitioning to CNG, equipping them with the knowledge to implement sustainable and resilient farming practices.

Speakers

Shelby Mendoza

Oklahoma State University

Friday August 1, 2025 8:45am - 9:00am CDT
Strand 11A

Oral presentation, Organic Horticulture 3

Subject Organic
Poster # csv

9:00am CDT

ORGH 3 - Targeting Challenges in the Transition to Organic Production with Educational Solutions

Friday August 1, 2025 9:00am - 9:15am CDT

Strand 11A

Momentum for sustainable and organic farming remains strong, driven by concerns for environmental stewardship, health, and social responsibility. As of the 2022 USDA Organic Certified Survey, the number of certified organic operations in the United States grew to 18,263, covering 5,083,623 acres. However, Mississippi continues to have a limited presence, with only 5 certified specialty crop operations as per the USDA Organic Integrity Database. Building on our initial findings, this year’s research continues to investigate the motivations and barriers producers face when adopting organic principles. In year two, we expanded the reach of our survey, pushing the 43-question instrument into all 50 states with the assistance of our partners. The survey remains focused on key challenges including social, environmental, and technical concerns. The core themes from year one—environmental consciousness, financial constraints, and the knowledge-implementation gap—remain prevalent, but we have also observed evolving trends in the responses. Producers continue to cite environmental and market motivations as key drivers. They emphasize the benefits of education on the producer and consumer level as a potential solution. Financial challenges remain a significant barrier, with many producers expressing concerns about the high costs of transition and the economic uncertainty during the process. New insights have emerged regarding the growing role of social networks and community support in facilitating the adoption of organic practices, suggesting that social capital may help mitigate some of the technical and financial challenges producers face. Our case study of a beginning farmer in Calhoun City, Mississippi, highlighted valuable insights into the specific challenges faced by farmers in a region where organic practices are still uncommon. It also highlighted the importance of bridging the knowledge gap and improving support systems for producers. The insights and data garnered have been used to develop a regional database of interested producers. These growers are helping refine recommendations and contribute to the development of targeted programs aimed at supporting the transition to organics including conferences, publication, and other educational efforts. These ongoing experiences continue to guide our understanding of the complexities of transitioning to organic agriculture, offering real-world examples that complement the survey data. As we move forward, we are also exploring how farmers' willingness to adopt organic practices evolves over time and how external factors may influence their decisions. This ongoing research plays a crucial role in advancing the transition to organic certification, ensuring producers are supported in their effort to pursue sustainable practices.

Speakers

Brenton Breland

Mississippi State University

Co-authors

Christine Coker

Mississippi State University

Ronald Stephenson

Plant Sciences Hall

Friday August 1, 2025 9:00am - 9:15am CDT
Strand 11A

Oral presentation, Organic Horticulture 3

Subject Organic
Funding Source USDA AMS

10:14am CDT

VCM 6 - Oral Session

Friday August 1, 2025 10:14am - 10:15am CDT

Strand 11A

Presiding/Moderator

Jordan White

Washington State University

Friday August 1, 2025 10:14am - 10:15am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

10:15am CDT

VCM 6 - Assessing sweetpotato growth response to growing degree days in western Washington

Friday August 1, 2025 10:15am - 10:30am CDT

Strand 11A

Studies in the Northeast United States and Canada have shown that sweetpotato yield can be comparable to the national average when grown with black plastic mulch. Western Washington has a diversity of microclimates, from the Pacific Coast to the Cascade Mountains, and assessing yield in response to growing degree days (GDD) will help growers determine if soil warming strategies are needed to achieve acceptable yield. This experiment was carried out in Mount Vernon, WA in 2024 and is being repeated in 2025. The experimental design was a split-split plot: the main plot treatment was bare soil and black polyethylene mulch (25.4 µm); the split plot treatment was cultivar, Covington and Cascade; and the split-split plot treatment was harvest date, every two weeks from 8 weeks after transplanting (WAT) to 18 WAT to assess root growth in response to accumulated GDDs. The experiment included 4 replications with 10 plants per plot, and raised beds with drip irrigation. Soil temperature was measured at 15-min intervals with sensors installed in both the mulch and bare soil plots. GDDs were calculated at two base temperatures, 10°C and 15.5°C, as both are reported in the literature. In 2024, for bare soil and plastic mulch treatments at base temperature 10°C, GDDs were 528 and 667 at 8 WAT (29 July), respectively, and 1080 and 1300 at 18 WAT (7 Oct.), respectively. At base temperature 15.5°C, GDDs for bare soil and plastic mulch treatments were 238 and 375 at 8 WAT and 428 and 635 at 18 WAT, respectively. At 8 and 18 WAT, GDDs for AgWeatherNet air temperature located 410 m from the field site were 629 and 1308 for 10°C base temperature and 138 and 275 for 15.5°C. Overall, black plastic mulch increased soil temperature by 1.78°C on average, and soil GDDs were 44% and 21% higher with plastic mulch compared to bare soil for a base temperature of 15.5°C and 10°C, respectively. At 18 WAT, root yield (US No. 1 and US No. 2) without accounting for wireworm damage was 11.7 t/ha for ‘Covington’ and 9.9 t/ha for ‘Cascade’ with plastic mulch and 7.7 t/ha for ‘Covington’ and 8.4 t/ha for ‘Cascade’ with bare soil. Sweetpotato yield in Mount Vernon, WA, was 35% greater on average with plastic mulch, but plastic mulch may not be necessary in warmer regions of the Pacific Northwest.

Speakers

Jordan White

Washington State University

Co-authors

Carol Miles

Washington State University

Laura Schulz

Washington State University

Friday August 1, 2025 10:15am - 10:30am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

10:30am CDT

VCM 6 - Assessing the Effect of Processing on Volatile Organic Compounds in Tomatoes Using Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry

Friday August 1, 2025 10:30am - 10:45am CDT

Strand 11A

The profile of volatile organic compounds (VOCs) in tomato (Solanum lycopersicum) fruit significantly influences their sensory attributes, particularly aroma, which affects consumer preference. This study examines variation in VOCs between commercially processed tomato products and greenhouse-grown tomatoes, focusing on processing techniques and how they alter VOC profiles. Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) was employed for detailed VOC profiling. Optimization of HS-SPME parameters, including salt-assisted extraction, extraction temperature, and fiber selection, enabled precise identification and quantification of VOCs. The optimized conditions involved extracting samples in a 30% NaCl solution to maximize volatile release, adsorption onto a 50/30 µm DVB/CAR/PDMS fiber at 80 °C for 30 minutes, and analysis using a Restek Rtx-Wax column with helium as the carrier gas. SPME-GC-MS analysis confirmed that processing techniques significantly influence the release, chemical nature, and composition of VOCs. Commercially processed tomato products exhibited elevated levels of volatiles such as (Z)-3-hexenal and (E)-2-hexenal. Since processed products often undergo thermal treatments such as pasteurization and decontamination, the reduction in volatile composition compared to fresh, unprocessed tomatoes could be attributed to the thermal degradation of heat-sensitive compounds such as cis- and trans-hexanol, hexanal, geranial, and methyl salicylate, contributing to a pronounced cooked tomato aroma. In contrast, greenhouse-grown tomatoes, cultivated under controlled conditions, contained lower overall VOC concentrations but retained higher levels of methyl salicylate and norisoprenoids, yielding a milder, sweeter aroma profile, which is generally absent in processed products. This study underscores the impact of processing on tomato aroma and highlights the importance of optimizing analytical methods for VOC profiling. Detailed VOC profiling offers valuable insights for breeders and food processors seeking to enhance the flavor quality of both greenhouse-grown and processed tomato products. This research was supported by USDA-NIFA-2024-51181-43464 and USDA-NIFA-AFRI-2023-67013-39616 through the Vegetable and Fruit Improvement Center and the Institute for Advancing Health Through Agriculture at Texas A

Speakers

Debanjan Chatterjee

Texas A

Debanjan Chatterjee, PhD, is a dedicated researcher specializing in natural products chemistry and pharmacological studies. He earned his B.Pharm in 2017, followed by an M.S. (Pharm) from the National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, in 2019... Read More →

Co-authors

Bhimanangouda S. Patil

Texas A

Braulio Cervantes Paz

Texas A

Deepak Kumar Jha

Texas A

Vikas Dadwal

Texas A

Friday August 1, 2025 10:30am - 10:45am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

10:45am CDT

VCM 6 - Phenological Assessment of Artichoke Grown with Gibberellic Acid–Induced Vernalization in a Subtropical Climate

Friday August 1, 2025 10:45am - 11:00am CDT

Strand 11A

Globe artichoke (Cynara cardunculus var. scolymus L.) is an herbaceous, perennial plant native to the Mediterranean region and belongs to the Asteraceae family. It requires adequate winter chilling for bud induction, yet susceptible to freeze damage. In subtropical or tropical climates, artificial flower induction or vernalization is necessary for winter crops. Our preliminary results indicate that gibberellic acid (GA3) effectively induces bud formation without chilling. Understanding crop phenology facilitates management planning and performance assessment under diverse conditions. This study used the Biologische Bundesanstalt, Bundessortenamt, CHemische Industrie (BBCH) scale to characterize the phenological development of artichoke cultivated in a subtropical climate with insufficient winter chilling. Seedlings of ‘Green Queen’ (GQ), ‘Imperial Star’ (IS), ‘Opal’ (OP), ‘20-063’, ‘22-017’, ‘23-057’, and ‘24-060’ cultivars were transplanted on 18 October 2024 in West Central Florida. Plants initially exhibited vegetative growth characterized by leaf development (Stage 1) and rosette formation (Stage 3–4) up to 79 DAP. GA3 applications at 62 and 76 days after planting (DAP) promoted vegetative growth by increasing both leaf number and size. Vegetative growth was most vigorous in ‘GQ’ and least in ‘20-057’, whereas in the Mediterranean climate, growth at this stage typically arrests through winter due to low temperatures. GA3 applications successfully induced bolting, initiating the transition to reproductive growth between 80 and 82 DAP. Buds reached the optimum maturity stage to harvest with the maximum diameter at around 115 DAP, earlier than the typical 120 to 150 days in annual culture. Marketable yields varied significantly among cultivars, from 2.69 t·ha–1 for ‘OP’ to 7.33 t·ha–1 for ’20-063’. By 160 DAP, mature buds exhibited floral opening with characteristic lilac-colored florets (Stage 6: flowering and capitulum formation). In Florida, although hot and humid summers constrain the harvest window, our results suggest that GA3-induced vernalization enables artichoke production during the winter months in a timeframe that is 5 to 35 days shorter than under Mediterranean conditions. This study advances understanding of artichoke adaptability to subtropical climates, promoting its potential as a winter specialty crop for edible and ornamental uses.

Speakers

Avninder Kaur

University of Florida

Co-authors

Shinsuke Agehara

University of Florida

Friday August 1, 2025 10:45am - 11:00am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

11:00am CDT

VCM 6 - Enhancing Bell Pepper Production: Exploring the Effects of AMF Application on WUE in Greenhouse Bell Pepper Production

Friday August 1, 2025 11:00am - 11:15am CDT

Strand 11A

Arbuscular mycorrhizal fungi (AMF) are a widespread and naturally-present soil microorganism that form symbiotic relationships with the roots of terrestrial plants. These fungi have been credited with numerous host plant benefits, the most relevant to this study being their ability to improve plant-water relations through multiple mechanisms. Bell peppers are extremely vulnerable to drought stress and require high amounts of water, so the colonization of AMF could potentially help fortify peppers against this prevalent stressor. However, AMF populations are greatly affected by the disruptive agricultural practices utilized in vegetable production. Therefore, there is a need to research the integration of AMF into traditional production systems. Existing research on AMF is often inconclusive and inconsistent when compared across locations and environments due to their complex nature. An AMF trial was carried out at greenhouses in Raleigh, NC to examine the effect of AMF application on water use efficiency (WUE) in bell peppers. ‘Red Knight’ F1 hybrid bell pepper seeds were inoculated with a commercially available AMF spore product (Endomycorrhizae formulation). The seeds then germinated and grew for eight weeks to allow the AMF root colonization to establish. Afterwards, the pepper seedlings were transplanted into 2 gal pots and placed on weighing lysimeters before growing for four more weeks to allow the roots to establish in the pots. Two irrigation treatments were then applied to the plants: 100% container capacity (CC) and water deficit (WD). The 100% CC treatments were irrigated in daily intervals to keep the media at maximum soil moisture. The WD treatments were individually irrigated back up to 100% CC each time visual wilting symptoms presented for a plant. Water use for each plant was calculated throughout the growing season by weighing the pots and runoff-catchment containers at each irrigation event to precisely determine the amount of water available to each plant. At the end of the growing season, WUE was determined for each plant by comparing the total water used to the total biomass produced. Results show no difference in WUE for the control vs AMF inoculated plants under water deficit. However, there were some differences observed in other measurements collected, such as floral abortion rates, plant height, biomass, stomatal conductance, and water pressure potential.

Speakers

Brooke Matusko

North Carolina State University

Co-authors

Amanda Cardoso

North Carolina State University

Emmanuel Torres Quezada

North Carolina State University

Kevin Garcia

North Carolina State University

Ricardo Hernandez

North Carolina State University

Friday August 1, 2025 11:00am - 11:15am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

11:15am CDT

VCM 6 - Optimizing Harvest Timing for Enhanced Hop Quality in a Subtropical Climate

Friday August 1, 2025 11:15am - 11:30am CDT

Strand 11A

Optimizing Harvest Timing for Enhanced Hop Quality in a Subtropical Climate Alvaro J. Bautista* and Shinsuke Agehara University of Florida, Institute of Food and Agricultural Sciences, Gulf Coast Research and Education Center, 14625 County Road 672, Wimauma, FL 33598, United States *Presenter: Alvaro J. Bautista Corresponding author: Shinsuke Agehara (sagehara@ufl.edu) Hops (Humulus lupulus L.) are a key ingredient in brewing, contributing bitterness, aroma, and microbiological stability. While traditionally cultivated in temperate climates, our previous research has demonstrated that subtropical regions like Florida offer unique opportunities for hop production, enabling two production cycles per year with supplemental lighting. Harvest timing is critical for optimizing hop cone biochemical composition, particularly alpha acids (AA), beta acids (BA), and essential oils, which directly influence beer quality. This study examined the seasonal and developmental dynamics of ‘Cascade’ hop cone chemistry to determine the optimal harvest window for both spring and fall growing seasons. Data were collected from 2021 to 2024 from the plants established in 2021 at the University of Florida’s Gulf Coast Research and Education Center in west-central Florida. Cone samples were collected at different days after flower induction (DAFI) to assess changes in AA and BA, cohumulone and colupulone, and essential oil composition. Acid levels showed significant seasonal variation. In spring, AA and BA ranged from 9.38% and 5.48% in 2021 to 4.48% and 2.0% in 2024, respectively. In fall, AA and BA ranged from 4.7% and 2.49% in 2021 to 2.97% and 2.0% in 2024, respectively. Acid accumulation also showed seasonal patterns, peaking at 36–48 DAFI in spring compared to 24–30 DAFI in fall. In contrast, cohumulone and colupulone maintained stable levels around 27.54% of total AA and 47.79% of total BA, respectively, throughout the study. Essential oil content increased during cone maturation, reaching its optimal aromatic profile at 36–42 DAFI (1.5 ml/100g). Myrcene (81.8% of total oil), the dominant terpene across all seasons, followed the same trend as total essential oil content. Humulene and caryophyllene peaked between 24 and 36 DAFI (19.7% and 10.9.% of total oil, respectively), while geraniol and linalool remained stable (0.5% and 0.7% of total oil, respectively) throughout maturation. These findings provide a foundation for optimizing hop production in non-traditional climates and highlight the importance of precise harvest timing to enhance hop quality for brewing applications. Future research will explore additional environmental, physiological, and management factors influencing hop maturation under subtropical conditions.

Speakers

Alvaro J. Bautista

University of Florida

Co-authors

Shinsuke Agehara

University of Florida

Friday August 1, 2025 11:15am - 11:30am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

11:30am CDT

VCM 6 - Quantifying Yield Attributes of Spring Sweet Corn Varieties (Bicolor, White, and Yellow) in the Southeastern USA

Friday August 1, 2025 11:30am - 11:45am CDT

Strand 11A

A comprehensive, two-year field evaluation of bicolor, white, and yellow sweet corn (Zea mays var. saccharata) varieties was conducted in southern Georgia during the spring seasons of 2022 and 2024. This research aimed to evaluate the yield and quality performance of commercial supersweet sweet corn varieties for the main kernel color market segments. The experiment was conducted at the Hort Hill Research Farm on the University of Georgia Tifton Campus. A total of ten bicolor, five white, and five yellow sweet corn varieties were used in this study. Significant interactions were observed between years and varieties, impacting ear characteristics and marketability. Overall, 2022 exhibited significantly higher ear and shank lengths, while 2024 had increased blank tip lengths and higher unmarketable ear counts. Among the bicolor varieties, ‘Redemption’ demonstrated exceptional performance with the highest ear length and width measurements, shank length, and the lowest blank tip measurements. ‘Grizzly’ had the lowest ear width, shank length, and highest blank tip measurements, while ‘American Dream’ recorded the shortest ear length. ‘Obsession’ and ‘Seminole Sweet’ had the highest marketable yield and 48-ear boxes per acre, reflecting their superior yield performance, whereas ‘Grizzly’ exhibited the lowest performance parameters, including the lowest marketable yield, total ear counts, and 48-ear boxes per acre. Additionally, ‘Superb’, ‘American Dream’, and ‘Courage’ recorded higher unmarketable ear counts per plot, which ultimately resulted in a significantly lower percentage of marketable ears. For the white varieties, there were no significant differences in ear characteristics and yield parameters. However, the yellow varieties displayed statistically significant differences in ear width and shank length. ‘GSS1170’ excelled, with the highest ear width and shank length, making it an excellent option for yellow corn production. Varieties ‘SC1336,’ ‘Astronaut,’ and ‘Passion’ had significantly higher unmarketable ear counts, with total ear counts also varying significantly among varieties, indicating differences in both productivity and marketability. Based on these research findings, the recommended varieties for optimal performance in ear characteristics and marketability are ‘Obsession’, ‘Seminole Sweet’, and ‘Redemption’ for bicolor corn and ‘GSS1170’ for yellow corn. These varieties exhibited excellent yield performance, making them ideal choices for growers seeking to increase yield. Conversely, since white corn varieties did not exhibit significant differences for any ear characteristics or marketability parameters, no specific recommendations can be made for this category.

Speakers

Manisha Kumari

Post-Doctoral Research Associate AD, The University of Georgia

Manisha Kumari is a post-doctoral research associate AD at Horticulture department, University of Georgia, Tifton campus, Tifton 31793, GA, USA.

Co-authors

Ted McAvoy

University of Georgia

Friday August 1, 2025 11:30am - 11:45am CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management

11:45am CDT

VCM 6 - Agrivoltaics: How Solar Panels Affect Bell Pepper 'SVPB8415' Production

Friday August 1, 2025 11:45am - 12:00pm CDT

Strand 11A

Agrivoltaics is a production system that allows for dual land use through the deployment of solar panels for energy production while maintaining agricultural production underneath and/or between solar panels. This study was conducted at the Alliant Solar farm at Iowa State University, Ames, IA. Treatments included bell pepper (Capsicum annuum ‘SVPB8415’) grown between and outside (open-field) the solar panels. For the solar panel treatment, two raised beds with white plastic mulch were created on each side of the single-axis solar tracking panels. Each bed was 19.5m long. Two beds on each side were spaced 1.5m (center to center). Two rows of open-field peppers served as the control treatment. Control beds were 6.7m long. All treatments were replicated three times. Peppers were transplanted on June 6, 2024 at 0.3m spacing, double row. HOBO soil temperature, air temperature, and light intensity sensors were installed on the same day. No pesticides were needed to manage pests. A total of 6 harvests occurred throughout the season on a weekly basis between September 6 and October 14. Plants between the solar panels yielded 52.1 kg per row while the open-field yielded 27.0 kg, a 48% increase in the solar treatment. From June to September, the air temperature was cooler than the control on average by 4 degrees Fahrenheit while the soil temperature was 3 degrees Fahrenheit cooler. Based on first year results, bell peppers show promise within an agrivoltaics production system. More data will be collected in the coming years on plant growth characteristics, soil moisture, and postharvest quality of peppers.

Speakers

Raymond Wilmes

Iowa State University

Co-authors

Ajay Nair

Iowa State University

Friday August 1, 2025 11:45am - 12:00pm CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management
Funding Source United States Department of Energy

12:00pm CDT

VCM 6 - Assessing the Efficacy of Green Manure and Mycorrhizae in Reducing Salt Stress on Tomatoes Grown in Miami Dade County, Florida

Friday August 1, 2025 12:00pm - 12:15pm CDT

Strand 11A

Climate change presents a serious challenge for the future of agricultural production, with communities around the world undergoing agroecological disaster as a result of rapidly developing climatic conditions. Among the most pressing concerns for coastal production is sea level rise and salt intrusion into agricultural soils. Such is the case with Florida, which is regarded as a developing “ground zero” of the climate crisis. Along with California, Florida is the largest tomato producer in the country but is greatly at risk from sea level rise and saltwater intrusion, and tomato crop suffers considerably under salt stress. However, regenerative agriculture (RA) techniques present an opportunity for reducing the effects of saltwater intrusion, as they can enhance crop resistance to stresses and facilitate Na leaching out of soil biomes and improve crop yields. This research project aims to test two RA techniques (green manure and mycorrhizal inoculation) as ameliorating agents of salt stress in tomato (Solanum lycopersicum cv. “Sanibel”). In greenhouse controlled conditions, two treatments of pigeon pea green manure was applied to soil prior to the planting of tomatoes (0g mulch [control] and 60g) and tomatoes were subject to two mycorrhizae inoculation conditions (no inoculation [control] and inoculation with the salt-resistant species Glomus intraradices). Tomato plants were then subjected to four irrigation water salinities (0, 4, 8, and 12 dS m-1). Saline treatments were prepared using Instant Ocean® Sea Salt and distilled water. Tomato plant chlorophyll content and fruit texture quality parameters were analyzed in order to determine the salt-stress ameliorating efficacy of these regenerative techniques.

Speakers

Luis Cendan

Florida International University

Co-authors

Amir Khoddamzadeh

Florida International University

Imran Ahmad

Florida International University

Madhugiri Nageswara-Rao

United States Department of Agriculture - Agricultural Research Service, Subtropical Horticulture Research Station

Friday August 1, 2025 12:00pm - 12:15pm CDT
Strand 11A

Oral presentation, Vegetable Crops Management 6

Subject Vegetable Crops Management
Poster # csv

1:44pm CDT

CITR 4 - Oral Session

Friday August 1, 2025 1:44pm - 1:45pm CDT

Strand 11A

Presiding/Moderator

Fernando Alferez

UF-IFAS

Friday August 1, 2025 1:44pm - 1:45pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops

1:45pm CDT

CITR 4 - Unlocking the Power of Brassinosteroid for Resilient Citrus Production in Florida

Friday August 1, 2025 1:45pm - 2:00pm CDT

Strand 11A

Brassinosteroids (Brs) are a natural group of hormones known for their significant impact on responses to both biotic and abiotic stresses across various plant species. Brs can also influence plant growth and fruit maturation. With the recent availability of commercial formulations, this plant growth regulator is becoming an increasingly popular management tool in agriculture. Our team has been working on understanding BRs mode of action in citrus, because information is still scarce. In Florida, citrus industry is now in decline due mainly to the citrus greening disease (HLB), which has become endemic in the state, with no potential cure in the horizon. The disease reduces internal fruit quality and compromises viability of young, newly planted citrus trees. Our work has unveiled that Homobrassinolide (HBr) may increase internal maturation in sweet orange under citrus greening endemic conditions. We have determined the optimal application rate and the most effective timing for Hamlin and Valencia cultivars. We have shown that the beneficial effects of HBr are more pronounced in the healthier trees. This has led us to adapt the use of HBr in combination with oxytetracycline (OTC) injections, as growers in Florida are now injecting OTC in mature trees to reduce HLB. Our results show that HBr, when used on OTC-injected trees, improve internal fruit quality significantly. In addition, we have found that treating young, newly planted trees with HBr induces a strong immune response by activating the salicylic acid pathway, resulting in a delay in HLB infection. We have also shown that other Br analog, Epibrassinolide (EBL) improve the cold tolerance of citrus trees when young, treated plants were exposed to -4 ℃ for 24 hours. In addition, we have also observed EBL are helpful in improving the postharvest fruit quality. This is of special interest in the northern part of the state, where fresh market citrus industry is expanding, as region often experiences frequent chilling conditions during winter months. All in all, we are showing that Brs may be a ready-to-use tool in Florida citrus industry.

Speakers

Fernando Alferez

UF-IFAS

Co-authors

carlos aucique-perez

UF-IFAS

Divya Aryal

SWFREC - University of Fl

Muhammad Shahid

UF-IFAS

Saoussen Ben Abdallah

SWFREC - University of Florida/IFAS

Shahid Iqbal

University of Florida

Friday August 1, 2025 1:45pm - 2:00pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops

2:00pm CDT

CITR 4 - Methyl Salicylate and Gibberellic Acid in the Rehabilitation of Huanglongbing-Affected Sweet Oranges

Friday August 1, 2025 2:00pm - 2:15pm CDT

Strand 11A

Huanglongbing (HLB), a devastating bacterial disease presumed to be caused by Candidatus Liberibacter asiaticus, disrupts normal plant physiology by inducing hormonal imbalances that impair growth, fruit development, and defense responses. With no known citrus germplasm exhibiting resistance to HLB, effective management strategies are essential for sustaining citrus production. This study focuses on the combined application of methyl salicylate (MeSA), a systemic acquired resistance (SAR) inducer, and gibberellic acid (GA₃), a growth-promoting hormone, as a potential strategy to improve tree health and mitigating symptoms in HLB-affected citrus orchards. The study is being conducted at UF-CREC in Lake Alfred, Florida, on 15-year-old Valencia trees grafted onto Swingle rootstock. Four treatments are being evaluated: Control, GA₃, MeSA, and GA₃ MeSA. Trees were sprayed every 45 days from July to November 2024 with GA₃ and MeSA at 10 ounces per acre. The study assesses key production parameters, including yield, fruit drop, canopy density, and fruit quality. Preliminary results indicate that GA₃ application reduced preharvest fruit drop by 57% compared to the control. The leaf water content was significantly higher in Ga MeSa (58.42%) as compared to Control. No significant differences in canopy density were observed across treatments. Leaves were collected for molecular analysis on Days 7, 14, 30, 46, and 60 after the first treatment application. Differential gene expression analysis revealed significantly lower transcript levels of Rboh and LOX2 within 7 to 14 days post-treatment in GA MeSA, suggesting a potential reduction in oxidative stress. In contrast, CDR1 expression was significantly higher in MeSA treated leaves between days 30 and 45, likely indicating SAR activation. These physiological responses may contribute to improved tree performance under HLB pressure. The study will continue into the next year to refine application strategies and better understand the sustained impact of these treatments on tree health and productivity.

Speakers

Gurleen Kaur

CREC, University of Florida

Co-authors

Tripti Vashisth

University of Florida

Friday August 1, 2025 2:00pm - 2:15pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops

2:15pm CDT

CITR 4 - Fine-tuning Propionic Acid Dosage for Reducing Pre-harvest Fruit Drop in 'Hamlin' Sweet Oranges and Mechanisms Involved

Friday August 1, 2025 2:15pm - 2:30pm CDT

Strand 11A

Pre-harvest fruit drop significantly challenges citrus orchard yield and economic viability, especially those affected by Huanglongbing (HLB). This issue is relevant in Florida’s citrus industry. This study investigated the efficacy of propionic acid he experiments applied three monthly doses of propionic acid in two consecutive years—in 2023 treated doses were 300 ppm, 1,100 ppm and 2,200 ppm— to trees, with an untreated group serving as the control. For this experiment, results indicated that the 1,100 ppm of propionic acid was most effective in controlling fruit drop, significantly reducing losses by 30% compared to the control. In 2024, the second experiment aimed to fine-tune doses. Trees were treated with three monthly doses of propionic acid utilizing 700 ppm, 1,100 ppm, and 1,400 ppm, with an untreated group serving as the control. Results showed that the 700 ppm dose was the most effective treatment in preventing fruit drop, retaining 15% more fruit than untreated trees. In both years, propionic acid increased average fruit weight. The 700 ppm dose improved yield by 36% compared to the control in 2024, while the 1,100 ppm dose led to a 17% increase in 2023 and 6% in 2024. Propionic acid did not alter fruit quality parameters, including °Brix and acidity. These findings suggest that propionic acid is a promising management tool for reducing pre-harvest fruit drop under HLB conditions.

Speakers

Pablo Orozco

SWFREC

Friday August 1, 2025 2:15pm - 2:30pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops

2:30pm CDT

CITR 4 - Evaluating Root Uptake of Gibberellic Acid as an Alternative to Foliar Application in Citrus

Friday August 1, 2025 2:30pm - 2:45pm CDT

Strand 11A

Huanglongbing (HLB), also known as citrus greening, is a devastating disease of citrus and has severely impacted the citrus industry in Florida, causing substantial economic losses. With no known cure, management practices just aim to mitigate the harmful effects on the tree. Recent studies have shown that the 5 monthly foliar applications (September-January) of gibberellic acid (GA) can reduce preharvest fruit drop, improve fruit set, and enhance tree health. The potential impact of these findings is huge for commercial citrus production; however, growers are looking for alternatives to foliar application as foliar sprays are highly weather dependent and expensive, currently an air blast sprayer application can range anywhere from $30 to $50 per acre. Therefore, it becomes critical to find alternatives to foliar GA application. Supply of GA to the plants through irrigation could be a valid alterative instead of foliar application. This study explores the feasibility of GA application through irrigation as an alternative to foliar sprays. Specifically, we investigated GA uptake efficiency through citrus roots, its effects on overall plant growth, and transcriptomic changes in leaves and roots. Preliminary results indicate that both foliar (GF) and root applications (GR) induced tree responses, altering the hormone profiles in leaves and roots. Fifteen days post application, GR showed significantly higher concentration of GA₁ (950 ng/g fresh weight (FW)), GA₃ (450 ng/g FW), and GA8(112 ng/g FW) in the roots whereas these hormones were undetectable in the GF or untreated controlled. In the leaves, GA3 was significantly higher (210 ng/g FW) in GF but undetectable in untreated and GR. At 30 days post treatment, an enhanced leaf growth response was observed in GF trees with a mean new growth of 35 leaves as compared to 20.2 in GR and 17.8 in untreated control. Similarly, a 60-day hydroponic study demonstrated that root GA application significantly increased leaf production (p = 0.04). Bud growth was also significantly higher in root-treated plants compared to controls at both 10 days (p = 0.01) and 20 days (p = 0.01) post-application These preliminary findings suggest that root-applied GA does not mimic foliar application effects but offers some benefits for plant growth. An in-depth, long-term analysis is underway to validate the potential of GA delivery via irrigation.

Speakers

Abhishek Neupane

University of Florida

Co-authors

Tripti Vashisth

University of Florida

Friday August 1, 2025 2:30pm - 2:45pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops
Poster # csv

2:45pm CDT

CITR 4 - Brassinosteroid-Induced Physiological Adaptations Improve Freezing Tolerance in Grapefruit (cv. Ray Ruby)

Friday August 1, 2025 2:45pm - 3:00pm CDT

Strand 11A

Brassinosteroids (BRs) are essential plant steroid hormones that regulate a wide range of developmental and physiological processes. In addition, these hormones play a significant role in helping plants cope with stress by modulating responses to various stressors, including heat, cold, drought, and heavy metals. Freezing temperatures during winter and spring pose a serious threat to citrus production, putting the sustainability of this newly emerging citrus industry in north Florida. Based on the protective effects of BRs, we hypothesized that exogenous application of BRs could enhance the basal tolerance of citrus plants exposed to freezing temperatures. To test this hypothesis, we evaluated the photosynthetic performance and cellular damage of cold sensitive grapefruit (cv. Ray Ruby) plants sprayed with BRs (6 ppm) under freezing stress. Plants were treated with BRs (0 and 6 ppm) at 12, 24, and 48 hours before freezing stress (hbfs). Plants maintained at 20°C and sprayed with BRs (0 and 6 ppm) served as controls. Following treatment, the plants were placed in a freezing chamber and subjected to a gradual temperature decrease until reaching -6°C, where they were maintained for 1.5 hours. Freezing stress induced greater cellular damage in exposed plants compared to those kept at 20°C. However, BRs-treated plants at 12, 24, and 48 hbfs showed approximately 30% less cellular damage compared to water-sprayed plants. Photosynthetic parameters were affected by freezing stress, leading to reductions in CO₂ assimilation (

Speakers

Carlos Aucique

Postdoctoral Associate, University of Florida

Co-authors

Charles Nauck

University of Florida

Fernando Alferez

UF-IFAS

KeAndre Leaks

University of Florida

Muhammad Shahid

University of Florida

Shahid Iqbal

University of Florida

Friday August 1, 2025 2:45pm - 3:00pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops
Poster # csv

3:00pm CDT

CITR 4 - Extending the Satsuma Harvest Window Through a Single Gibberellic Acid Application

Friday August 1, 2025 3:00pm - 3:15pm CDT

Strand 11A

The Georgia citrus industry is rapidly growing. The citrus farmgate value increased by ~70% from 2022 ($22.4M) to 2021 ($13.2M). More acres of citrus are put in every year and, as of 2024, there are nearly 5,000 acres of citrus across the southern half of the state. Of this acreage approximately 60% are satsumas. This has generated a bottleneck for packinghouses as a majority of the citrus grown in the state reach an acceptable maturity at the same time. Georgia citrus growers have expressed an interest in expanding the harvest window of their existing plantings so more fruit can reach the market. The plant growth regulator, gibberellic acid (GA), has historically been used to delay color break in Florida citrus. Unfortunately, the existing recommendations from Florida are not applicable to the citrus varieties grown in Georgia. The present works aims to develop GA recommendations for Georgia satsumas. GA was applied at a rate of 0, 8, 10, 15, 20 ppm (n = 4) prior to color break in August 2024. The 15 and 20 ppm concentrations saw significantly less red and yellow color development by mid-December (p

Speakers

Mary Sutton

University of Georgia

Co-authors

Jacob Kalina

University of Georgia

Friday August 1, 2025 3:00pm - 3:15pm CDT
Strand 11A

Oral presentation, Citrus Crops 4

Subject Citrus Crops
Funding Source Georgia Farm Bureau

3:15pm CDT

CITR 4 - Insights into Pre-Harvest Rind Disorder in Mandarins Under California Growing Conditions

Friday August 1, 2025 3:15pm - 3:30pm CDT

Strand 11A

The citrus industry experiences considerable losses due to a physiological rind disorder that compromises mandarin fruit quality and marketability—particularly in cultivars like Satsuma Owari. This disorder, characterized by water-soaked areas that progress to brown lesions, is likely triggered by multiple factors, including environmental conditions such as high relative humidity and rainfall. It typically appears after fall rain events and is more prevalent in fruit from the outer canopy. Our study, conducted in a commercial orchard in California’s San Joaquin Valley, explored the role of environmental conditions, rind water status, and potential management strategies. We found that treatments applied at the color break stage, 2,4-dichlorophenoxyacetic acid (2,4-D, 16 mg/L), gibberellic acid (GA₃, 20 mg/L), and Vapor Gard® (0.5% v/v)—significantly reduced rind damage. However, GA₃ delayed external color development by approximately four weeks. Susceptibility to rind disorder varied by cultivar, with Kishu being the most susceptible, followed by Satsuma Owari and Gold Nugget, while Page, Tango, and W. Murcott exhibited greater tolerance. We also investigated biochemical, hormonal, and molecular changes associated with the disorder. Damaged tissues showed reduced cellulose concentrations but similar levels of pectin and hemicellulose compared to healthy tissue. Additionally, damaged rinds had higher hydrogen peroxide (H₂O₂) content and increased peroxidase (POD) and polyphenol oxidase (PPO) activities. Metabolomic and hormonal profiling identified 76 metabolites, with 43 differing significantly between healthy and damaged tissues, highlighting the involvement of jasmonic acid and related compounds in the disorder’s development. Transcriptomic analysis further revealed differential expression of genes involved in stress responses, cell wall degradation, and hormone signaling between healthy and affected tissues. These findings suggest that delaying rind senescence using targeted treatments may reduce the incidence of this disorder. This research provides new insights into the physiological, biochemical, and molecular basis of mandarin rind disorder and offers practical management strategies to mitigate fruit losses across different varieties.

Speakers

Oral presentation, Citrus Crops 4

Subject Citrus Crops
Funding Source California Citrus Research Board