Take a moment to relax and recharge with a complimentary seated massage in the exhibit hall! Offered exclusively to conference attendees, this refreshing experience is available on a first-come, first-served basis, so be sure to stop by early. Whether you need a quick escape from the hustle and bustle or a moment to unwind between sessions, our skilled massage therapists will help melt away tension—leaving you refreshed, reenergized, and ready to make the most of your time at the conference. Don't miss out on this perfect opportunity to treat yourself!
Tuesday July 29, 2025 11:00am - 4:00pm CDT Empire AB
Biochar, a carbon-rich material produced from biomass pyrolysis, has potential to absorb and provide mineral nutrients for plant growth. Anaerobic digestion is a process where microbes decompose organic material without oxygen in sealed vessels to produce digestate and biogas. In this study, biochar was utilized to sequester mineral nutrients during anaerobic digestion of vegetable waste and used to deliver nutrients to a growing leafy green vegetable. Fresh vegetable biomass was used as a feedstock in a novel 80 L cartridge anaerobic digester in Spring 2024. Biochar was placed in the digester liquid effluent for a minimum of 30 days to absorb nutrients liberated by the digestion process. Biochar was analyzed for nitrogen, phosphorus, and potassium content to determine plant culture treatment levels. A plant culture greenhouse experiment (lat. 40.51ºN; Normal, IL) was conducted in Fall 2024. Seeds of lettuce (Lactuca sativa ‘Newham’) were grown to transplant size. One week after seedling emergence, a soluble 20N-4.4P-16.6K fertilizer was applied to seedlings every seven days at a rate of 100 mg/L N. Approximately three weeks after emergence, individual plants were transferred to 3.8 L plastic pots filled with soilless media. Fertility treatments were maintained at 70 mg/L N using the following ratios of commercial 20N-4.4P-16.6K Fertilizer:Biochar;100%:0%, 90%:10%, 80%:20%, 70%:30%, and 60%:40% by weight, respectively, as a media-incorporated, preplant application. Pots were arranged in a completely randomized block design. During plant growth, media Electrical Conductivity (EC) and leaf Soil Plant Analysis Development (SPAD) were measured every five days. Media EC decreased (P≤0.001) and leaf SPAD increased (P≤0.001) across all treatments during growth. Lettuce was harvested at 50 days post-seeding when it reached marketable size. At harvest, shoot and root fresh mass were measured, and fresh tissue was dried at 60ºC for dry mass determination. For lettuce, total biomass, shoot FM, root FM, shoot DM, and root DM at harvest all decreased, and then increased quadratically (P≤0.001) as Fertilizer:Biochar ratios changed from 100%:0% to 70%:30%. The highest lettuce per plant total biomass was 176.92 g per plant under 100% commercial fertilizer. Harvest EC increased linearly (P≤0.001) and SPAD decreased, then increasing quadratically (P≤0.001) as Fertilizer:Biochar ratios changed from 100%:0% to 60%:40%. Observed Fertilizer:Biochar response patterns indicate a delayed nutrient release from biochar over time. Additional research on the timing of nutrient release from biochar and possible uses as a commercial fertilizer for vegetable crop production continues to be warranted.
Guayule, Parthenium argentatum Gray, is a perennial shrub native to the Chihuahuan desert of Mexico and Texas. It is known for its latex and rubber production, which are viable alternatives to Hevea rubber. However, guayule seeds have low germination rate, which doesn’t meet commercial requirements. Guayule seeds have a germination rate between 55% and 87%, but this is highly dependent upon priming and soil temperature. Newer guayule lines have been developed, but the germination rate still varies. There is very little literature on successful priming methods in guayule seeds, most of which have been performed on historic lines in the 1980’s and 1990’s. To determine how newer lines are affected by different priming methods, we treated seeds with seven priming treatments and a control, then studied germination rates over 14 days. The treatments included: treatment 1 – control; Treatment 2 – Presoaking in 25% PEG, 10-4 M gibberellic acid, 0.05% KNO3, and 0.1% thiram fungicide adjusted to a pH of 8 with Ca(OH)2 and soaked for 4 days; Treatment 3 – Mildly scarified with fine sandpaper; Treatment 4 – Treatment 2 scarification; Treatment 5 –DI water soaking for 6 hours; Treatment 6 – Soaking with 75 ppm NAA and IAA, 1M KH2PO4 for 24 hours; Treatment 7 – Soaking in a DI water/ 0.1 M KNO3 solution for 12 hours; and lastly treatment 8 – Soaking in DI water for 8 hours, followed by soaking them for 2 hours in a solution of equal parts gibberellic acid (200 ppm) and 0.25% NaOCl. There were significant effects of treatment, line, and interactions of line and treatment on seed germination. Scarification had the overall highest germination percentage, followed by soaking in DI water for 6 hours and the control. The lowest germination was seen in lines soaked in DI water, followed by a bleach and gibberellic acid solution. Line E008 showed the highest germination rate, followed by E001, E009, E002, and E010. The interaction effects were highly variable, but indicated that each line was affected differently by the seed treatments. These results show that treatments to improve germination may need to be tailored to specific lines to optimize germination in guayule.
Guayule (Parthenium argentatum Gray) has been produced as an alternative natural rubber crop in the U.S. for over 100 years with varying success. Selecting and breeding for higher yielding rubber and latex has been a priority for establishing guayule as a feasible alternative rubber and latex source, but many environmental conditions affect yields. Previous research has shown regional variability which means regional evaluation of guayule should be conducted for optimal regional line selection. Readily available lines, AZ1 - AZ4, and 11591, among others, were evaluated in the Southern High Plains over 20 years ago. Since then, newer lines have been developed with higher latex yields and quality. Therefore, an experiment was designed to evaluate three of these lines (E002, E003, E004) in greenhouse conditions. Growth parameters, health ratings, canopy temperatures, and bark thickness were measured regularly. Lines E003 and E004 had significantly larger canopy circumferences and plant height than line E002, however, plant health rankings were higher in E003 followed by E002, then E004 lines. Trunk diameter was also greater in E003 and E004 lines, but bark width did not significantly vary among treatments. Bark parenchyma cells are the site of rubber particle production, and therefore as bark thickness increases, rubber may also increase. These results indicate that while the E003 and E004 lines are larger, the rubber production may be higher in E002 in comparison. Many other factors continue to be examined, but these preliminary results further illustrate that line selection is essential, and overall biomass may not be the best factor for selecting high yielding lines.
Rutgers Cooperative Extension is committed to developing and delivering integrated pest management (IPM) related programming for the commercial nursery, professional landscape industries, and their customer base, home horticulturalists. Here the tactics utilized to develop and deliver IPM programming are highlighted in efforts to assist horticulture professionals navigating an ever-tightening academic personnel climate. The Extension Cycle approach of stakeholder needs assessments, securing funding, educational program development with deliverables, and evaluation has led to significant impacts. In the last year alone, over 300 surveyed stakeholders, representing over 6K acres managed, indicated that they gained knowledge about IPM practices and science-based tools, and nearly 100% plan to adopt these practices, with early-adopters realizing cost savings/profits over $1M. This is important due to size of these industries as the 2019 Census of Horticultural Specialties, indicated $13.8B in sales for floriculture, nursery, and specialty crop goods, while supporting the $153B landscape industry, which provides over 1M jobs nationally (NALP). New Jersey currently ranks fifth in the nation for nursery stock sales ($296M) and third in potted flowering plants ($77.5M), locally supporting around 10K jobs and driving $950M in annual economic impacts (Sullivan & Schilling, 2020). US ornamental industries have unique needs in terms of IPM due to the shear complexity of pests associated with the number of crops grown and diversity of systems. Needs assessments were required to identify key IPM program targets and were compiled through post-program /twilight surveys, state-wide ornamental IPM and native plant needs assessments, and communication with stakeholders. Notable pests emerged and led to the development of educational programs coupled with deliverables including the Rutgers Pest Scouting Guides –Growing Degree-Days, Redheaded Flea Beetle - Predictions, [pictorial] Reference Guide to Common Boxwood Pests and Diseases, Oomycete Material Options, Diagnostic Education Series, and IPM Essentials for Ornamentals. In the last year over 250 education sessions on IPM related topics have been delivered to 15K stakeholders by Rutgers Nursery working group personnel, encompassing over 50 academic, grower/manager, home horticulture, and regulatory groups. Multiple streams of funding were secured to support this work (over $400K in 2024). Dissemination of information has taken many forms; hardcopy monthly newsletters, digitally through listservs and Rutgers Plant and Pest Advisory blog, and bi-weekly in-season lunch hour webinars that address contemporary IPM related topics. Taken together, personnel limited programs are often the norm, thus creatively leveraging the Extension Cycle and homing in on key needs has led to significant impacts.
Timothy J Waller, Ph.D. is serving in his fourth year as the Commercial Nursery Agent of Rutgers Cooperative Extension in southern NJ, based out of Cumberland County. Tim has a Ph.D. in Plant Biology with a focus on fungal plant pathology and has been a licensed pesticide applicator... Read More →
2024 marked Mississippi State University’s South Mississippi Branch Experiment Station’s fourth year to host a Poinsettia Open House. The goal of this annual event was to ascertain the affinity tendencies among retail consumers for poinsettias available in the US market. In addition, five new pre-release varieties not currently offered in any market were included. Results are intended to be shared within the industry. This event took place over a two-day period the first week of December (December 6, 2024 and December 7, 2024). The use of available poinsettias in various floral display arrangements provided participants with ideas for using these versatile plants in holiday inspired settings. Attendees were asked to complete a consumer preference survey in exchange for a complementary poinsettia to take home. The survey design asked for ‘favorites’ within the categories of traditional red, pink, white, novelty, and pre-release varieties. In addition, participants were asked to list their top 3 favorites regardless of the category. Overall, 60 total cultivars across these 5 categories were displayed in small groups of 6-8 plants each. Top votes getters within the 5 categories included: Reds – Christmas Feelings Merlot and Christmas Bells, Pinks – Maren and Jubilee Pink, Whites – Alpina White and Frozen, and Novelties – Superba New Glitter and Premium Ice Crystal. The entries within the pre-release category were identified as numbered selections. The top favorite within this category was a variegated dark pink/cream medium-height plant with large bracts. This new cultivar was also chosen as one of the overall participant favorites joining Superba New Glitter and Alpina White.
KY Farm Launch is a new beginning farmer training program designed in broad collaboration with organizations working with beginning farmers in Kentucky. This includes University of Kentucky (UK) Cooperative Extension and academic departments, the Kentucky Center for Ag and Rural Development (KCARD), the Kentucky Sheep and Goat Development Organization (KSGDO), and an advisory board of non-profit agencies, beginning farmers, and experienced farmer leaders in Kentucky. The project team implementing the program is a partnership between UK Cooperative Extension, UK's Food Connection, UK Department of Horticulture, UK's Beef Team, KCARD and the KSGDO. This intensive program meets once per week for 9 months in Lexington area, based at UK's Horticulture Research Farm and Organic Farming Unit, UK's Animal Research Unit, and other privately-owned farms supporting the program. Our goal is for program participants to begin farming commercially within one year of completing the program. The program consists of full day of workshops each week focused on production knowledge, hands-on skill building, and farm business development. All participants complete a 'Common Curriculum' of business and market planning, financial record keeping, risk management, and farmland evaluation and assessment (~8 weeks). The bulk of the program is divided into two tracks that participants select based on their primary commercial enterprise: the Sustainable Vegetable Small Fruit Track or the Diversified Livestock Track. The 'Track-Based Programming' (~24 weeks) is applied, hands on training in essential aspects of commercial production of diversified vegetables and small fruits (Veg Small Fruit Track) or sheep, goats, small flock poultry, and small beef cattle herds (Livestock Track). Additionally, each participant works with the team to develop individualized mentoring plans to help fill any gaps in their knowledge and interests. For farmers without access to land, this program is also supporting the development of a beginning farmer incubator program in a partnership between UK and private landowners. This individually-tailored, cohort-based, hands-on approach is designed to accelerate participants progress to successful commercial farming at goal levels developed through a facilitated mentoring process. The program is capped at 30 farms (individuals or farm family units) per cohort cycle. The program will run for at least two consecutive cohort cycles (2025 and 2026). This poster will focus on the curriculum, learning objectives, methods and preliminary outcomes of the Veg Small Fruit track at the mid-way point through our first cohort.
Rutgers Master Gardeners (RMG), a 45-year-old program with over 2,000 active volunteers, assist the Agriculture and Natural Resources Department of Rutgers Cooperative Extension in the implementation of its goals. The Extension’s goals include the provision of accurate, research-based, practical information regarding horticulture best practices to extended community of New Jersey. The program evolved organically since its inception and there has been no statewide research that examined the program’s operation and impact. In July of 2024, an extensive survey was sent to 2250 volunteers categorized “active” in the master database. This survey, Volunteer (1), solicited information regarding the volunteers’ motivation for serving, their understanding of the program’s operation, training and funding and tested some future program ideas. A second survey, Volunteer (2), followed. This survey clarified or further explored items from Volunteer (1) and added an impact assessment. A third survey, Rutgers Staff/Faculty, aimed to determine alignment of staff/faculty perception with those of the volunteers as well as to examine the staff/faculty perception of the program’s operation, training and funding. A fourth survey, National, was distributed through the Extension Master Gardener list serve to staff and faculty administering each state’s Master Gardener Program. It examined the alignment of Rutgers program with the national program to obtain a deeper understanding of Rutgers work. All data collected should be considered perception and opinion data. There was both alignment and misalignment were found within and between all surveys. Some unexpected data reveal potential anti-volunteer bias and lack of program leadership clarity. On-going focus group sessions and further surveys and workshops continue to clarify trends. Trends identified, include suggest restructuring of program staffing, enhancing strategic planning and focusing on professional development and support of volunteer coordinators. Data informs the initiation of a strategic planning initiative for the statewide program.
Ruth Carll serves as the State Leader of Consumer Horticulture and Master Gardener Programs for Rutgers University. She is an innovative leader in the botanical education field. After earning her Master of Botany from Arizona State University, she led the education and volunteer program... Read More →
Tuesday July 29, 2025 12:15pm - 1:00pm CDT Empire AB
Citrus is one of the most widely grown fruit crops worldwide with a total of $2.98 billion in productivity in the U.S. However, the citrus industry has been significantly affected by Huanglongbing (HLB) which caused as much as 90% production loss in Florida. Efficient phenotyping and data management will aid breeding selection and hasten the development of high yielding citrus varieties with durable resistance to HLB. The Citrus Genome Database (CGD, www.citrusgenomedb.org), an integrated web-based community database for citrus genomic, genetic, and breeding research, offers the Breeding Information and Management System (BIMS) for efficient public or private data management. BIMS is compatible with Field Book, an Android app which allows breeders to collect data on phones or tablets. In addition, the compliance of BIMS and Field Book with the Breeding API (BrAPI) enables seamless data transfer between them. This transition to electronic data collection and data management using BIMS has boosted the efficiency of the University of Florida citrus breeding program. Under the 2022-funded SCRI-project ‘Advanced National Database Resources for Specialty Crop Research and Improvement’, we aim to collaborate with citrus breeding programs across the U.S., offering in-person or webinar training on BIMS and Field Book, while sharing updates on these tools with citrus breeders.
Nutrient availability is an essential aspect of plant growth and development. Sandy soils have low nutrient-holding capacities. Huanglongbing (HLB) trees have lower fine root density and thus decreased capacity to uptake nutrients. Organic amendments have been known to increase nutrient-holding capacities in sandy soils and provide additional nutrients. The objectives of this study were to 1) determine the influences of organic amendments on citrus production on sandy soil, and 2) assess the potential of organic amendments to alleviate the negative impacts of HLB. The study was conducted over six months in a greenhouse setting at the Citrus Research and Education Center in Lake Alfred Florida using Valenica sweet orange on Swingle citrumelo rootstock grown on Candler fine sand. Treatments of compost (5% and 10% by volume) and peat moss (5 and 10% by volume) and a control composed of Candler fine sand without amendment were applied to a total of 50 trees, 25 of which were HLB-affected and the other 25 were healthy trees. The following variables were measured: tree diameter, tree height, leaf chlorophyll content, soil nutrient content, tissue nutrient content, soil organic matter content, and biomass and nutrient accumulation. Organic amendments improved soil organic matter content by 20 to 40%. Organic amendments also increased plant and root growth parameters and demonstrate an ability to alleviate the negative impacts of HLB. Our research will eventually be followed up by field studies to validate the greenhouse observations.
Senescence of branches or twig dieback due to tree age or disease in mature citrus orchards (>8 years old) is common. Moreover, strategic pruning and hedging are standard practices to sustain tree health and yield. As a result of these practices, a large amount of biomass without economic value is either left in the field, mulched into the soil, or disposed with minimum control on nutrient recycling. This study aimed to use this biomass as feedstock for biochar production. We pyrolyzed this material to produce biochar with modest amounts of macro and micronutrient content. This citrus-based biochar was applied a fixed rate to return the equivalent of 10 kg N ha-1, and contrasted with the other commercially available biochars. Preliminary data indicates that all biochars were capable of increasing soil moisture retention compared with the control. Fertility analysis of each biochar indicates diverse availability of macro and micronutrients that can complement current fertilization programs. Moreover, biochar incorporation as soil health management strategy may increase the recalcitrant pool of carbon in the soil, with its accompanied benefits. Future research aims to evaluate soil microbial respiration affected by biochar application.
Huanglongbing (HLB), or citrus greening, has severely impacted citrus production in Florida, with no known cure currently available. Growers have increasingly adopted soil-focused management strategies, including cover cropping, to improve soil health and support tree resilience. In the Indian River District, where sandy soils with low fertility and organic matter prevail, the potential for cover crops to influence the soil microbiome remains underexplored. To investigate this, a three-year field trial was established in collaboration with a commercial grower and the University of Florida, IFAS, Indian River Research and Education Center, in Ft. Pierce. The trial included ‘Star Ruby’ grapefruit trees grafted on ‘US-942’, ‘Bearss’ lemon trees grafted on ‘Sour Orange’, and ‘OLL’ sweet orange trees grafted on ‘US-942’ rootstock. A randomized complete block design was used to compare conventional management (no cover crops) to a cover crop system, with species planted biannually and terminated at the end of each season. Soil microbiome composition and diversity were assessed seasonally through high-throughput sequencing, alongside measurements of soil nutrients, organic matter, moisture, and temperature. Early results suggest that the use of cover crops may influence soil microbial communities, with some differences observed between treatments over the three-year period. These include modest shifts in microbial diversity and structure, although the functional significance of these changes remains unclear. These findings suggest that cover crops may influence the soil microbiome in HLB-affected citrus groves, potentially contributing to improved soil conditions and offering a possible strategy to support long-term sustainability in southeast Florida citrus production systems.
Dr. Rossi’s research program focuses on understanding the responses of horticultural crops to environmental stresses, with the goal of developing environmentally sound and effective management strategies. He is a horticulturist with expertise in plant stress physiology, plant biology... Read More →
Fruit retention is a critical factor for citrus growers, as fruit that remains on the tree to be harvested is the fruit that gets paid for. The challenge has been exacerbated by Huanglongbing (HLB), a disease that significantly increases premature fruit drop, making it essential to identify the key factors influencing fruit retention. In this study, the relationship between fruit size, leaf count, seed viability, and fruit detachment force (FDF) was investigated to better understand what contributes to fruit retention on the tree. A total of 30 fruit per tree in four trees were tagged,fruit size and leaf count on the fruiting branch were recorded and monitored over five weeks., In the second week, Ethephon (150 ppm) was sprayed to induce faster fruit drop. Weekly measurements were taken to track fruit drop. At the end of the study period, the remaining fruit were removed along with their stems to measure FDF, viable seed count, and aborted seed count. The findings indicate a positive correlation between the fruit’s FDF and leaf count, suggesting that fruit with more supporting foliage are more likely to remain attached. Additionally, a negative correlation between the number of aborted seeds and FDF was observed, implying that fruit with more aborted seeds are also more susceptible to detachment. These findings were strengthened by comparing the average values of leaves and aborted seeds between the fruit that had to be manually removed and the fruit that dropped prematurely. The prematurely dropped fruit had a significantly lower number of leaves (9 vs. 16.4 average) and a higher aborted seed number (1.9 vs. 0.9 average). These insights should motivate growers to find therapies that promote leaf growth for a more profitable orchard. The study also points to a need for further investigation into the causes of seed abortion to get a clearer picture of the basic mechanism causing HLB-induced fruit drop.
Puakenikeni (Fagraea berteroana) is a popular flower in lei making in Hawaii, especially during graduation season and mothers day, which coincide with the flowering period. Most of the propagation is done via air layers, to promote early flowering. Propagation via rooted cuttings has been reported in the literature, however, there are is no information in regards to best practice, and it is a common question asked to the the University of Hawaii at Manoa Cooperative Extension Services. This trial used different powder rooting hormones to compare their effectiveness in propagating semi hardwood cuttings of puakenikeni. Cuttings were dipped in the rooting hormone, and the lower 2 inches of each cutting was inserted in a mix of 50% perlite and 50% vermiculite and placed in a mist bench for 2 months. Three treatments were compared (no rooting hormone, and 0.1%, 0.3% and 0.8% IBA). A total of 80 cutings were used, or 20 cuttings per treatment. After two months the control treatment with no rooting hormone had only 10% rooting. The 0.1% IBA and 0.3% IBA had 30% and 10% rooted cuttings, respectively. The 0.8% IBA treatment had 85% rooting success. Results from this trial indicate that a rooting hormone with 0.8% IBA should be used when rooting semi hardwood cuttings of puakenkeni (Fagraea berteroana). Future trials may be performed to compare other concentrations and types of rooting hormones (powder, liquid and gel), in order to achieve higher rooting percentage rates.
The growing demand for sustainable landscapes and eco-friendly practices has significantly influenced consumer interest in native plant species. Agastache spp. is a xeric species naturally acclimated to the Rocky Mountain region and is valued for its ornamental flowering and exceptional landscape resilience, particularly in arid environments. However, one challenge is the limited availability of saleable plants due to challenges during asexual propagation, in particular, successful adventitious rooting of cuttings. Therefore, a study was conducted to evaluate the impact of different indole-3-butyric acid (IBA) rooting hormone concentrations on root initiation and development of Agastache ‘Coronado Red’. A total of 72 uniform stem cuttings were collected and 18 stems were treated with one of four experimental treatments that included, control (water), 1000, 3000, and 8000 ppm IBA concentrations. Cuttings were stuck in 72-cell trays and placed on a propagation misting bench, using a randomized complete block design. Destructive data collection occurred on a bi-weekly basis, with three collections. The experiment was repeated over the course of two production seasons. Two weeks after sticking, while callus initiation was present on cuttings for all treatments, an increase in both the number of primary roots and root length was observed as the concentration of IBA increased. For example, the number of primary roots was greatest for cuttings provided the IBA concentration of 8000 ppm (16) compared to the control (0.2) and IBA concentrations of 1000 (3.4) and 3000 ppm (6.3). Similarly, length of the longest root was 1891%, 144%, and 62% greater under the IBA concentration of 8000 ppm compared to the control and IBA concentrations of 1000 and 3000 ppm, respectively. Stem length and the number of nodes were similar for all treatments. These results indicate that higher IBA concentrations promote root initiation and growth as early as two weeks after sticking for Agastache ‘Coronado Red’. While results from the present study indicate that an IBA concentration of 8000 ppm is optimal for early establishment of Agastache ‘Coronado Red’ cuttings, future research is required to determine propagation strategies for other cultivars.
Plant growth and development depends on essential macronutrients such as nitrogen (N), phosphorus (P), and potassium (K), and deficiencies in these nutrients result in significant physiological and morphological changes. Leaf biochemical and biophysical properties influence light absorption and reflectance across various wavelengths, providing insights into canopy health. Advancements in high-throughput (HT) digital phenotyping technologies, including high-resolution scanning and multispectral imaging, have improved plant health assessment and monitoring. The TraitFinder, a digital phenotyping system developed by Phenospex, is equipped with two PlantEye-600 multispectral 3D laser scanners that generate three-dimensional plant models while capturing multispectral data. The system directs light in green (G), blue (B), red (R), and near-infrared (NIR) wavelengths onto the plant canopy and captures the reflected signals, which are then used to compute vegetation indices for plant health evaluation. This study utilized the TraitFinder system to determine reference values for vegetation indices associated with healthy plants and those deficient in N, P, and K. Four ornamental species—coleus (Solenostemon scutellarioides), marigold (Tagetes patula), petunia (Petunia × hybrida), and celosia (Celosia plumosa)—were evaluated over time. The experiment followed a randomized complete block design with eight replications and four nutrient treatments: a complete Hoagland’s solution and three modified versions, each lacking one macronutrient (N, P, or K). Morphological traits, such as biomass, showed reduced plant growth under nutrient-deficient conditions. Spectral data revealed common trends in nutrient-deficient plants, including decreased Green Leaf Index (GLI) and Normalized Difference Vegetation Index (NDVI) and increased Normalized Pigment Chlorophyll Ratio Index (NPCI) and Plant Senescence Reflectance Index (PSRI) compared to controls. In healthy plants, GLI ranged from 0.2 to 0.35, NDVI from 0.4 to 0.75, NPCI from 0.10 to 0.45, and PSRI from 0.07 to 0.25. However, species-specific responses to nutrient deficiencies were also observed. This study highlights the distinct morphological and physiological responses of ornamental species to macronutrient deficiencies and demonstrates the effectiveness of digital phenotyping using the TraitFinder system for tracking plant health over time. The findings emphasize the potential of HT digital phenotyping which could enhance ornamental crop management.
High fertilizer costs and environmental impacts are growing concerns in modern agriculture, and the floriculture industry is increasingly adopting the use of biostimulants to enhance plant growth, stress tolerance, and nutrient use efficiency. Despite their potential, the effectiveness and specificity of many biostimulants remain poorly understood. This study evaluated the growth-promoting effects of Lalrise Vita, a commercial biostimulant containing the phosphate solubilizing bacteria Bacillus velezensis. Lalrise Vita's impact on plant growth and health was evaluated using Tagetes patula ‘Durango Yellow’ (French marigolds) and Viola × wittrockiana ‘Clear Yellow’ (pansies). The first experiment evaluated how fertilizer at increasing concentrations affected the plant responses to the biostimulant. A water-soluble fertilizer delivered 50, 150, 300, or 600 mg·L–1 nitrogen (N) from 15N–2.2P–12.5K–2.9Ca–1.2Mg applied once weekly with 100 mL of solution per pot. Lalrise Vita was applied once at transplant at 0.25 g per plant as a substrate drench of 100 mL of solution per pot, with untreated plants as controls for both experiments. The second experiment focused on phosphorus (P) fertilization, with plants receiving increasing P concentrations of 2.5, 5, 10, or 20 mg·L–1 from KH₂PO₄ once a week along with the fertilizer. Plants were fertilized weekly with 100 mL of solution delivering 200 mg·L–1 N from 15N–0P–12.5K–2.9Ca–1.2Mg. Plants were scanned using the Trait Finder (Phenospex), and digital biomass, normalized pigment chlorophyll ratio index, plant senescence reflectance index, and HUE were used to identify differences in plant growth and health. In marigolds, Lalrise Vita improved digital biomass and plant health across all fertilizer rates compared to untreated plants. The greatest differences were observed at lower fertilizer concentrations (50 and 150 mg·L–1 N). Significant improvements were observed in pansies at 50 mg·L–1 N, including increased biomass and improved health indicators. Marigold plants treated with Lalrise Vita at 5 and 10 mg·L–1 P had greater growth, although spectral variables indicated greener foliage at higher P rates in untreated plants. There were no significant differences in pansies between treated and untreated plants, suggesting that Lalrise Vita-treated plants receiving 2.5 mg·L–1 P performed comparably to those receiving 20 mg·L–1 P without Lalrise Vita. Excessive fertilizer (300 and 600 mg·L–1 N) reduced Lalrise Vita’s benefits, as phosphate-solubilizing bacteria are less effective when P is not limiting. However, Lalrise Vita can be used to grow quality crops with reduced fertilizer applications.
Easter lilies (Lilium longiflorum) cultivated in the greenhouse industry are often treated with plant growth regulators (PGRs) to control their height by reducing stem length. A greenhouse study was conducted to examine the effects of uniconazole “Sumagic” on the growth of a new cultivar of Easter lilies ‘White Spring’. Treatments consisted of five bulb sizes based on circumference (12/14, 14/16, 16/18, 18/20, 20/22 cm) and uniconazole rates of 0, 2.5, and 5.0 mg•liter-1 with eight replications. Data collection consisted of stem height measured weekly, days until anthesis, number of flowers, and phytotoxicity rating. The results of the study showed a relationship between the uniconazole treatments and plant height, control plants had a greater average height (57.8 cm) than the bulbs soaked in 2.5 and 5.0 mg•liter-1 uniconazole, (33.5 cm) and (23.8 cm), respectively. Plant heights were also influenced by bulb size as they increased in height with increase in bulb circumference. The average number of days until anthesis increased with smaller bulb circumference, as anthesis was delayed. Days until anthesis were also affected by the uniconazole treatments, the bulbs treated with 2.5 and 5.0 mg•liter-1 solutions took approximately 6 and 8 days longer, respectively. Phototoxicity effects displayed as chlorosis on leaf tips and margins occurred in both the 2.5 and 5.0 mg•liter-1 solutions with symptoms more prominent in larger bulb sizes.
Soil pH shapes rhizosphere microbial structure and diversity, influencing nutrient cycling, plant growth, and ecosystem health. However, the effects of pH on the microbiome in greenhouse-grown ornamental plants in peat-based soilless substrates are less well understood. This study examined the impact of substrate pH and plant species on rhizosphere bacterial communities to see how the interaction of these factors influenced microbial diversity. A two-factor experiment with substrate pH (4.5, 5.5, 6.2, and 7) and plant species (geranium, marigold, petunia, and tomato) was conducted in a greenhouse with six replicates per treatment (n=6) in a random complete block design. Substrate-only controls were included at each pH level to evaluate plant species influence on the bacterial community. The peat-based substrate pH was adjusted with dolomitic limestone. Plants were fertilized at each irrigation with 100 µg·g-1 N from 15-5-15-Ca-Mg fertilizer. After eight weeks of growth, the ornamental plants were fully flowering, and the tomato plants were beginning to bud. At that time, plant morphology and vegetative indices were evaluated by 3D image analysis, vegetive tissue and substrate leachate were evaluated for nutrient content, and rhizosphere samples were collected to evaluate bacterial composition and diversity by 16S amplicon sequencing. Plant species differentially modified the substrate pH from the starting levels. Geranium and marigold acidified the substrate, tomato tended to increase substrate pH, and petunia maintained pH close to the initial values. Shannon diversity indices indicated that bacterial diversity varied across the pH and plant species treatments. At pH 4.5, geranium, marigold, and tomato plants reduced the diversity relative to the no plant control. Geranium and tomato plants also reduced diversity at pH 5.5, while petunia plants at 5.5 exhibited the highest diversity across all plant species (p=0.0159). Beta diversity analysis identified pH as the dominant factor explaining 53.7% in Bray-Curtis dissimilarity and 68.5% in the weighted UniFrac distance metrics (both p
Peach (Prunus persica) production in the southeastern United States, particularly in South Carolina, is challenged by high humidity, variable chill accumulation, and persistent disease pressure – especially from bacterial spot (Xanthomonas campestris pv. pruni) adn brown rot (Monilinia spp.). In response, Clemson University reestablished its peach breeding program in 2008 with the goal of developing fresh-market cultivars adapted to this region’s demanding conditions. After more than a decade of field evaluation and selection, three new cultivars have been released under the ‘CaroRes’ and ‘EveRes’ series: ‘CaroRes Wonder’ (USPP 36,072), ‘EveRes Ruby’ (USPP 36,112), and ‘CaroRes Delight’ (USPP approved). The ‘CaroRes’ name signifies both Clemson’s South Carolina origin and disease resistance, while ‘EveRes’ identifies cultivars that combine disease tolerance with a slow-softening phenotype, allowing fruit to remain firm on the tree longer than standard melting types. All three cultivars are vigorous, productive, and well-suited to southeastern U.S. orchard systems. The cultivars exhibit high fruit tolerance to bacterial spot. In replicated trials, they demonstrated reliable productivity and good pack-out percentages with minimal split pit incidence. The fruits are large, round, and clingstone, with light pubescence and a high percentage of red skin blush, ranging from 80% to 95%. All cultivars have yellow melting flesh, though ‘EveRes Ruby’ exhibits a firm, crisp texture at harvest that gradually softens over several days at room temperature, enhancing postharvest handling and shelf life. ‘CaroRes Wonder’ and ‘CaroRes Delight’ ripen in the early season, while ‘EveRes Ruby’ ripens in the early to midseason. Across all three cultivars, fruit quality evaluations consistently rated flavor, texture, and appearance highly. These releases provide new options for growers seeking disease-tolerant cultivars with excellent fruit quality, reliable performance, and adaptability to the environmental challenges of the Southeast. Their unique combination of field resilience, consumer appeal, and handling advantages makes them strong candidates for fresh-market production. Trees are available through licensed TN nurseries, including Cumberland Valley Nurseries and Vaughan Nursery.
The production of blackberry, a valuable fruit crop, is primarily limited to USDA Zones 5 and higher. However, wild species such as Rubus allegheniensis, R. alumnus, and R. rosa are widespread from Zones 5 through Zone 3a in Minnesota and Wisconsin. Native species are a valuable, untapped genetic resource, which could provide both hardiness for production in colder areas with short growing seasons and resilience to pests, diseases, and climate change for warmer areas. The use of native species for breeding has been limited as little research has been conducted to date. To access the utility of this germplasm, propagation protocols developed for them will need to be established. Because sexual and vegetative propagation requirements for the genus Rubus vary widely depending on taxa and genotype, this research aims to evaluate protocols specific to these species. Canes were collected from 24 northern locations to test rooting of softwood cuttings with either IBA and NAAm auxin treatments in early spring and again in summer. Additional canes were collected from one location to test the rooting of dormant cuttings using IBA and bottom heat to stimulate root growth. Results indicate that the suitability of softwood cuttings for propagation is dependent on the section of the genus, with samples over 30% of samples from section Procumbentes (dewberries) rooting, while sections Arguti, Canadenses, Rubus (highbush blackberries), Setosi (bristleberries), or Ideaobatus (raspberries) all had under 10% rooting rates. In addition, seeds were collected from 5 locations to test germination protocols. Seeds were divided between two stratification treatments(20°C control and a six-month at 4°C). Within those, seeds received either no scarification, physical scarification, 30 minute acid scarification, or 3 hour acid scarification treatments. The 30 minute acid scarified seeds were also divided between a control and aqueous smoke solution treatment. Results from germination tests indicated that long acidic scarification treatments do not result in increased germination at six months.
Papaya ringspot virus (PRSV) is a devastating pathogen found throughout the tropics and subtropics. Understanding PRSV diversity and evolution is crucial for formulating timely management strategies and breeding resistant cultivars. The molecular epidemiology of PRSV-P was investigated by analyzing the nucleotide sequences of the coat protein gene of different PRSV isolates worldwide, including the sequence data generated by collecting infected samples from South Florida. PRSV samples were collected from different papaya growing regions in Homestead and the wild papaya plantations surrounding Lake Okeechobee. Distinct PRSV clades were identified, corresponding to the U.S. and South American region, Southeast Asia (excluding India), and specifically India. The sequences obtained in the present study showed a close correlation with the aligned with the sequences from Cuba, Mexico, Jamaica, Guatemala, Venezuela, and previous sequences of the Florida isolates. The estimates of PRSV diversity showed an increase in the viral diversity, as the majority of the papaya growing regions are forming a separate clade. However, the evolution is slow, which could be due to the implementation of control strategies and the cultivation of resistant transgenic papayas.
Lack of winter chill accumulation is a major limiting factor for blackberry production in regions with mild or absent winters. For blackberry buds to release endodormancy they must be exposed to a range of temperatures between 0-7°C for a period of time that is genotype-specific. Insufficient chill in blackberries results in incomplete bud development, irregular budbreak, extended flowering periods, nonsynchronous fruit set, and lower fruit yields. The University of Arkansas Division of Agriculture (UADA) Fruit Research Station, located in Clarksville, Arkansas, experiences 1000 hours of annual chill each year, inhibiting the identification of low chill germplasm in the Arkansas Fruit Breeding Program. This study compares two methodologies for determining chilling requirements in six blackberry cultivars (Von, Natchez, Navaho, Ouachita, Sweet-Ark® Ponca, and A-2491T). Long-cane blackberry plants were exposed to controlled artificial chilling in a cooler, with removal at six weekly intervals from 0 to 840 hours, followed by exposure to forcing conditions in a heated greenhouse. Concurrently, field-grown plants of the same cultivars were exposed to naturally occurring chill hours in the field with six stem cuttings per genotype collected biweekly and forced under a mist bed in a heated greenhouse. The number of buds broken, reproductive laterals, and open flowers were recorded on a weekly basis for both methods. Results indicated that both methods effectively differentiated chilling requirements across cultivars, with budbreak and flowering progressing more rapidly and synchronously once plants reached their cultivar-specific chilling requirement. This study aims to identify an effective, repeatable method of evaluating blackberry chilling requirement in Arkansas to inform breeding decisions and identify low chill material in UADA blackberry germplasm.
I am a graduate research assistant of the University of Arkansas Fruit Breeding Program, pursuing my MS in Plant Breeding and Genetics. My research focuses on investigating the diversity of chilling requirement within the University of Arkansas blackberry germplasm.
Blueberry is the second major fruit crop in Alabama, followed by peach. However, blueberry production in Alabama is marginal compared to neighboring states such as Florida, Georgia, and North Carolina. Alabama growers still rely on old rabbiteye cultivars due to a lack of access to southern highbush blueberries (SHB) that are adaptable to the region. SHBs are valued for their early maturation and fruit quality but have not been widely adopted in Alabama due to their susceptibility to spring frost and other possible biotic or abiotic stresses. This project aims to introduce frost-tolerant SHB cultivars in Alabama through multi-environment cultivar evaluation. A total of 12 cultivars and 25 advanced selections of SHB have been evaluated in two locations in Alabama: the E.V. Smith Research Center (EV) in Central Alabama and the Brewton Agricultural Research Unit (BW) in South Alabama. Plants have been evaluated for 50% bloom, average berry weight (g), yield per plant (g), Brix (%), titratable acidity (TA%), and firmness (g/mm). Data from 2024 revealed that San Joaquin (5,035 g) and NC5289 (3,798 g) had the highest average yield at EV. At BW site, TH-2976 (3,375 g) and NC5289 (2,984 g) showed the highest yield. Colossus and Patrecia produced the largest average berry weight for both locations. In the BW, Colossus had an average berry weight of 4.72 g and Patrecia 3.8 g. At the EV location, both Colossus and Patrecia had an average of 3.0 g berry weight. For Brix, FL12-213A (14.7) and NC5326 (14.2) had the highest values at EV, while NC5326 (14.2) and Sentinel (13.8) had the highest values at the BW location. Overall, late-blooming selections such as NC5314 and NC5289 were identified as more suitable for Alabama to mitigate spring frost damage. The frost-tolerant cultivars identified through this project will significantly benefit small to mid-sized growers in Alabama by ensuring stable fruit production.
Macadamia is a commercially valuable nut crop, but the global industry is predominantly based on self-infertile cultivars. Pollinator scarcity can result in reduced nut set and lower yields. The development of self-fertile cultivars provides an opportunity to produce consistent yield in the absence of pollinisers and pollinators and may enhance orchard profitability. While previous studies identified varying degrees of self-fertility in macadamia, a comprehensive understanding of genetic diversity within a broad range of germplasm and the mechanisms of this trait remain unexplored. This study involved 11 commercial cultivars to identify genetic variation and mechanisms associated with self-fertility. An outcross pollen exclusion method was employed to assess self fertility. The percentage ratio of self- to open-pollinated nuts were calculated as a measure of self-fertility. To investigate the mechanisms underlying self-fertility, spatial separation of male and female reproductive organs as well as site of pollen tube growth inhibition have been examined. Pistil length, stamen length and stigma-anther distance were measured over two flowering seasons. Fluorescence microscopy was used to observe the pollen tube growth after self-pollinations. The self-fertility ranged between 17%-65% for six cultivars (‘HAES 741’, ‘HAES 791’, ‘A38’, ‘UQM40’, ‘K’, ‘Q’), which were identified as self-fertile. Five cultivars (‘HAES 344’, ‘A16’. ‘Daddow’, ‘D4’, ‘A268’) were identified as self-infertile. Pistil length of self-fertile cultivars ranged from 12.5 to 14 mm. Except for ‘A268’, which had significantly shorter pistils (8.5 mm), the pistil length of the self-infertile cultivars ranged from 11.5 mm to 14.5 mm. Stigma-anther distance was not associated with self-fertility. It was found that all cultivars exhibited similar stigma-anther distance, ranging from of 6 to 8 mm. There was non significant difference between the self-fertile and self-infertile groups for morphological floral traits. Pollen tube was inhibited in the upper third of style in self-incompatible pollinations. This inhibition indicated gametophytic self-incompatibility in macadamia. Further study will use a diverse collection of macadamia germplasm, including commercial cultivars, breeding lines and wild accessions to estimate heritability of self-fertility. Additionally, differential expressed genes in the pistils of self-fertile and self-infertile cultivars will be examined to understand the molecular mechanism regulating the trait. This research will assist in breeding of high-yielding, self-fertile cultivars for future plantations, ultimately supporting the sustainability of macadamia industry.
Black raspberry (Rubus occidentalis) and purple raspberry (R. idaeus x occidentalis) are fruits known for their pleasant and distinctive flavors. However, unlike their more popular cousin red raspberry (R. idaeus), little is known about what defines the characteristic aromas of black and purple raspberry. Using SPME-GCMS, the chemical compounds in the headspace of pureed black raspberry (4 genotypes), purple raspberry (5 genotypes), and red raspberry (2 genotypes) were collected and identified through a combination of gas chromatography and mass spectrometry. Chemical concentrations were calculated by integrating the area under the chromatogram curve, and calibrated with an internal standard of 2-octanol. By utilizing a random forest model, chemicals that were the most important for distinguishing fruit types (red vs. black vs. purple) were determined. Of the top 30 chemicals, 12 chemicals were described on Flavornet as detectable by a human nose in gas chromatography-olfactometry (GC-O), and the typical aroma described. Those 12 chemicals were then evaluated individually for significant differences across types (red, black, and purple raspberry). Among the chemicals that differed significantly across species were D-Carvone (caraway aroma), 1,3,8-p-Menthatriene (turpentine aroma); β-Ionone (violet, flower, raspberry, and seaweed aromas); α-Ionone (violet aroma); 2-Hexenol (leaf, green, wine, and fruit aromas); and α-Terpineol (oil, anise, and mint aromas). These results have implications for breeding new black and purple cultivars with the expected characteristic flavor. This instrumental approach also allows for tracking these aromas in breeding populations when utilizing interspecific hybridization to broaden the black raspberry germplasm in breeding.
The Vitis genus consists of two subgenera, Vitis and Muscadinia, which are both cultivated for wine, juice and fresh consumption. Fresh market breeding programs for grapes (V. vinifera) and muscadines (M. rotundifolia) aim to develop stenospermocarpic seedless and perfect-flowered cultivars. Despite chromosome differences and genetic divergence between the Vitis (2n=38) and Muscadinia (2=40) subgenera, stenospermocarpic seedlessness from V. vinifera was successfully introgressed into M. rotundifolia through conventional breeding. Currently, molecular markers for stenospermocarpy have not been developed or validated in Muscadinia and diverse Vitis accessions. Before the divergence of the Vitis and Muscadinia subgenera, two mutations occurred in perfect flowered ancestors, leading to male and female sterility and resulting dioecy in wild plants from both subgenera. Kompetitive Allele Specific PCR (KASP) markers have been recently developed targeting the known causal mutations resulting in male sterility (VviINP1) and stenospermocarpy (VviAGL11) in Vitis. The markers named, seedless_Arg197Leu_site56.fas and female_INP_indel_site56.fas, were evaluated for their diagnostic potential across Vitis and Muscadinia species through sequence alignments with published genomes. The predictive ability of these markers was assessed using a validation panel from the University of Arkansas Division of Agriculture Fruit Breeding program, which included 918 seedlings from Vitis x Muscadinia hybrid breeding populations. Additionally, a range of diverse Vitis and Muscadinia accessions with known phenotypes were included to enhance understanding of marker effectiveness, including cultivars, selections, and wild material from USDA germplasm repositories and public and private breeding programs. In total, 209 diverse accessions were assessed with the seedless marker, and 320 accessions were evaluated with the flower sex marker. The evaluation for seedlessness and flower sex took place over 2023 and 2024. Excluding incomplete phenotype and genotype data, the stenospermocarpic marker (seedless_Arg197Leu_site56.fas) accurately predicted seedlessness in 921 of 924 entries. Additionally, 148 out of 203 seedlings that did not produce fruit in both growing seasons were predicted to be stenospermocarpic. A t-test comparing vine caliper between seeded and seedless material (P =0.178) showed no difference in vigor between the seeded and seedless vine and suggested that the high number of seedless vines with no fruit may be caused by sterility factors linked to the introgressed Vitis stenospermocarpy locus. The flower sex marker (female_INP_indel_site56.fas) correctly predicted flower sex in 1,137 of 1,138 entries. Overall, the KASP markers showed outstanding predictive performance, achieving accuracy rates of 99.9% for flower sex and 99.7% for seedlessness across Vitis, Muscadinia, and hybrid germplasm.
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
'Ga. 6-1-269' is an hermaphroditic muscadine grape (Vitis rotundifolia) with bronze berries that was released by the University of Georgia (UGA) College of Agriculture and Environmental Sciences. Yields of ‘Ga. 6-1-269’ in Tifton, GA and Citra, FL trials were similar to other popular fresh-market muscadine cultivars. Berry size is very large (15-16 g) and similar to the cultivars 'Ga. 6-2-26' (Paulk®) and 'Supreme'. Fruit rot susceptibility of ‘Ga. 6-1-269’ was less than the bronze check cultivar 'Ga. 1-1-48' (Hall®) and similar to the black check cultivars 'Ga. 6-2-26' and 'Supreme'. Harvest time of ‘Ga. 6-1-269’ was about 5 days after 'Ga. 1-1-48' and about a week before 'Ga. 6-2-26' and 'Supreme'. ‘Ga. 6-1-269’ is recommended as an early-midseason fresh market bronze muscadine cultivar.
Kale (Brassica oleracea L. var. acephala) is a highly nutritious cruciferous vegetable valued for its abundant phytochemicals, particularly carotenoids such as β-carotene, lutein, and zeaxanthin. These compounds play crucial roles in human health by acting as antioxidants and precursors to vitamin A, aiding in the prevention of non-communicable diseases such as cancer, cardiovascular disorders, and age-related macular degeneration. Despite the health benefits of carotenoids, their concentration in kale can be significantly influenced by environmental and agronomic factors, particularly nutrient availability. Magnesium (Mg), an essential macronutrient and a core component of the chlorophyll molecule, plays a pivotal role in photosynthesis, enzyme activation, and nutrient translocation. While its role in general plant metabolism is well established, the impact of magnesium fertilization on carotenoid accumulation in kale remains underexplored. This study investigates the effect of different magnesium fertilization rates (12.3 mg/L, 24.6 mg/L, 36.9 mg/L, and 49.2 mg/L) on the accumulation of carotenoids and elemental nutrients in three kale cultivars—Darkibor, Mamba, and Red Russian—under hydroponic conditions. A split-plot experimental design will be implemented in a greenhouse using an NFT (Nutrient Film Technique) system. The research will evaluate chlorophyll (‘a’ and ‘b’) contents in the leaves, fresh and dry biomass, crop height, crown diameters, elemental nutrient concentrations using the ICP mass spectroscopy method, and carotenoid levels through HPLC analysis. The results will be statistically analyzed using ANOVA in RStudio. This study seeks to identify optimal magnesium application rates that enhance the nutritional quality of kale, providing insights into sustainable fertilization strategies for maximizing the health benefits of this functional crop.
Watercress (Nasturtium officinale L.) is a leafy green vegetable, that is a member of the Brassicaceae family. It provides a rich and bioavailable source of vitamin C, significantly higher than many fruits and vegetables, including oranges. Vitamin C is associated with numerous health benefits, such as antioxidant protection, immune system support, enhanced collagen production, improved iron absorption, improved eye health and lowered risks of chronic diseases such as cardiovascular disease and cancer. Thus, consuming adequate amounts of vitamin C daily is important for human health. A 100g of watercress provides 62mg (103% Recommended Dietary Allowance) of vitamin C. In humans, vitamin C takes part in various physiological processes; however, due to the functional loss of the gene coding for L-gulonolactone oxidase, humans cannot synthesize vitamin C and must rely primarily on plant-based foods for their needs. For this reason, increasing the vitamin C content of crops is essential for supporting human health. Some studies have shown potential effects of fertilization, particularly magnesium fertilization on vitamin C content. Therefore, this study aims to contribute to optimization of nutrient management in hydroponics to enhance nutritional value. The research was conducted using a split-plot design. Four magnesium fertilization rates (100 mg/l, 150 mg/l, 200 mg/l and 250 mg/l) were applied to watercress in Nutrient Film Technique (NFT) hydroponic system under controlled environment, ensuring desirable nutrient application, temperature, light, pH and electrical conductivity. Spectrophotometric methods were used to quantify Vitamin C. The preliminary findings indicate an increase in Vitamin C content with an increase in magnesium application rates, with the highest rate maximizing its accumulation. These results contribute to understanding the effects of magnesium fertilization on vitamin C synthesis in watercress and will help guide farmers and producers in optimizing vitamin C content during production to support human dietary needs and health. Keywords: Watercress, Vitamin C, Magnesium Fertilization, Hydroponics, Nutrient Optimization
Two nitrogen (N) sources – synthetic urea ammonium sulfate (UAS, 33-0-0) and organic bloodmeal (BM, 13-0-0) were evaluated for growing tea transplants in southeastern Louisiana. In Expt. 1, UAS and BM were applied at three rates (150, 250, and 350 lbs. N/A/year) to a 1-year-old tea field. Expt. 2 evaluated five treatments by substituting UAS with BM at 0%, 25%, 50%, 75%, and 100%, all at 350 lbs. N/A/year, applied to a 2-year-old tea field. N applications were divided into seven applications and applied every 40 days from April to October in 2023 and 2024 for a total of 11 applications. Despite periodic pruning to encourage branching for the building of a plucking table, plant growth metrics, such as leaf greenness and size index were similar across treatments in both experiments. However, tissue nitrogen concentration (N%) was consistently higher in BM-treated plants compared to UAS-treated plants at all application rates in Experiment 1. The highest tissue N% was also observed in the 100% BM treatment in Experiment 2. One year after treatment initiation, plants fertilized with UAS exhibited faster recovery after pruning compared to those treated with BM, though this difference diminished over time. In both experiments, plots treated with blood meal or more than 75% blood meal replacement resulted in less acidification compared with those treated with UAS. Further research on leaf quality (e.g., health-promoting compounds) and a more comprehensive evaluation of soil microbial activity are required to refine recommendations for nitrogen application rates and sources for tea production.
Planting a cover crop in orchard middles can have many benefits for the health of the trees. In California, improved water infiltration, especially during the winter rainy season, is a common motivation for cover cropping, and the benefit to soil health through increased biological activity resulting from biomass incorporation is also gaining renewed attention. Cover crops can also play a part in nutrient management by “mining” and holding existing nutrients, especially nitrogen, at the end of the season and, when legumes are included, by direct sequestration of nitrogen from the atmosphere through the symbiosis of their roots with nitrogen-fixing bacteria. Different cover crop types can contribute in different ways to these outcomes, but benefits depend on successful establishment and a significant amount of biomass being produced. We evaluated three common cover crop types over three years in a walnut orchard in northwestern San Joaquin valley with a heavy clay-loam soil. Treatments included a pure stand of winter triticale, a ‘pollinator’ mustard mix (multiple Brassica spp. plus Raphanus sativus [Daikon]), and a multi-species mix including grain rye and triticale, mustards (Sinapis alba and Raphanus sativus), and legumes (Vicia faba, Vicia sativa, Lathyrus oleraceus). Treatments were planted with a seed drill in two adjacent orchard middles at two parts of the orchard in early Nov. 2022, 2023, and 2024 and depended on rain for germination and growth. In 2023 and 2024, unplanted controls were maintained in rows adjacent to the trial rows. Sampling plots were defined at five representative points in the planted rows. Just before cover crop termination early in the April following each planting, above ground vegetation was sampled using a one-meter quadrat. While triticale and the mustard blend produced above ground dry biomass at 0.13 to 0.28 and 0.04 to 0.27 kg/sq. m, respectively, the multi-species mix consistently produced three to five times that amount, ranging from 0.53 to 0.68 kg/sq. m. Analysis of soil sampled one week before cover crop termination in 2025 did not show significant differences in organic matter, N, P, and K content, but samples of chopped cover crop taken at termination showed plant N content twice as high in the multi-mix treatment than in the others. This trial has highlighted the resilience of planting a diverse plant mix in comparison to more homogeneous cover crop types, and the advantage of including legumes when N may be a limiting factor to cover crop biomass growth.
Specialty Crops Advisor, UC Agriculture and Natural Resources
UC Cooperative Extension Advisor for Alameda and Contra Costa Counties, serving production horticulture. Current work focuses on IPM and biocontrol, cover crops, and irrigation management.
The leafy greens have generated significant worldwide interest due to their nutritional quality. Cress is among the leafy greens that are known for their nutrient-dense, phytonutrient content. Upland cress (Barbarea verna) is among the Cress varieties with tender greens known for their vibrant flavor and impressive nutritional profile. It possesses high metabolic activity, which enables it to synthesize a rich variety of phytonutrients. Magnesium, as a macronutrient, is known for influencing the biosynthesis of plant metabolites, including the glucosinolates biosynthesis pathway. The high accumulation of glucosinolate in upland cress could not only increase its nutritional quality but also market demand. The study assessed by supplementing magnesium fertilization rate on upland cress grown under a Nutrient Film Technique (NFT) system to identify the magnesium concentration that led to maximum accumulation of glucosinolate and biomass in upland cress. The split plot design was used, where four treatments of magnesium fertilization rates (100 mg/l, 150 mg/l, 200 mg/l, and 250 mg/l) were used. All treatments were under a controlled environment, ensuring nutrient application, temperature, light, pH, and electrical conductivity are in a good range required for Upland cress. After two weeks of germination, the Upland cress reached its maturity stage, and samples for leaf biomass were collected, and High-performance liquid Chromatography (HPLC) was employed for glucosinolate analysis. Preliminary findings showed that the magnesium fertilization rate of 150 mg/l and 200 mg/l stimulated high accumulation of leaf biomass and glucosinolate in upland cress, and the research is still ongoing. Keywords: Upland cress, Magnesium fertilization, leaf biomass, nutritional quality, Hydroponics.
Spinach (Spinacea oleraceae) is one of several vegetable crops commercially grown in Controlled Environment Agriculture (CEA). Recent research has indicated differences in root morphology and architecture among various crops may influence performance and environmental stressor tolerance. Specifically, fast-growing cultivars have shorter life cycles, develop more extensive and specialized root systems with increased root order differentiation in response to their growth systems. Contrastingly, slow-growing cultivars have greater heat-tolerance and produce simpler root systems with less root-order differentiation and fibrous roots. These root traits may be exploited to increase yield, promote efficient nutrient use, and mitigate environmental stressors. Novel studies have revealed an ideal root system archetype, known as “Subsoil Foraging Ideotype (SFI)”, wherein a well-penetrating taproot is able to easily maintain nutrient and water flow while optimizing resource efficient root development. We designed an experiment to measure differences between various spinach cultivars in CEA systems to reveal morphological variation which can aid in the development of SFI architecture cultivars. Our experiment utilized two growth systems located in a walk-in greenhouse, standalone NFT hydroponic systems with two inch net pots and expanded clay aggregate media, and one gallon pots to replicate field conditions. Seeds from fast-growing “Income”, medium-growing “Darkside” and slow-growing “El-Majestic” cultivars were transplanted into different growing systems. Supplemental light totalling 200 µmole/m2/s with 12 hour photoperiod and periodic fertigation was used. Harvests were conducted on days 15, 30, and 45, with the collection of leaf and root biomass. Collected data included scanning of root systems in WinRhizo software, measuring length, root volume, root diameter, surface area, classification by diameter, forks, tips, and crossing numbers. On day 45, four plants per cultivar were selected for anatomical analysis through microscopy evaluation and underwent JB4 embedding protocol. Anatomical analysis of five root orders included diameter, vascular development, and rhizodermis characteristics. Preliminary results suggest there is an interaction effect between cultivar, growth system, and developmental stage on spinach root morphology. All cultivars developed more extensive, specialized root systems under hydroponic conditions versus field counterparts where extensive root development was limited to fast-growing cultivar. Root diameter was greater in fast-growing cultivars, with decreased root order diversification of slow and medium-growth cultivars. These results affirm previous research which links root morphology to growth systems and environmental conditions. Cultivars which possess resilient traits may be further developed in conjunction with SFI archetypes. Such advances would further nutrient use efficiency and shrink growth cycles in CEA.
This study evaluated the growth and yield performance of two lettuce cultivars (Lactuca sativa L. cv. Green Forest’ and ‘Rouxai’) and freshwater prawn (Macrobrachium rosenbergii) across three production systems: coupled aquaponics (CA), de-coupled aquaponics (DA), and aquaculture hydroponics (AH). In the CA systems, water continuously recirculated between a hydroponic tank (HT), aquaculture tank (AT), and biofilter. In the DA systems, the HT remained separate from the AT and biofilter, but water was occasionally transferred from the AT to the HT. The AT and biofilter were also separated from the HT in AH systems, with no solution intermixing. Our study, conducted in a high tunnel supplied with municipal water (Texas A
Spinach is a commonly grown greenhouse crop, thus production practices have been honed over the years. However, additional strategies to improve production efficiency, yield, appearance, and nutritional quality are needed to continue improving the long-term feasibility of production. Light is a major environmental factor that influences the growth and quality of spinach, however, adding supplemental light is energy intensive and can be costly. A strategy to minimize electrical use while increasing crop quality is end-of-production (EOP) lighting where the light provided to the plant is altered just before harvest and not throughout production. The objective of this research was to determine the effect of EOP light intensity, quality, and duration on the growth and post-harvest characteristics of spinach ‘Space’ (Spinacia oleracea). Propagation was 14 days; then seedlings were transplanted into deep-water culture systems and grown for an additional 21 days in a common greenhouse environment. During production, HPS supplemental lighting was used to create a 16-h photoperiod and a daily light integral of 9.0 ± 2.3 mol·m−2·s−1. Seven, 3, and 1 day before harvest, broad-spectrum white LEDs [17:40:43 R:G:B] provided additional light intensities of 0 (control), 100, 200, 400, and 600 µmol·m−2·s−1, and red/blue LEDs [53:1:46 R:G:B] provided 200 µmol·m−2·s−1 for a 16-h photoperiod. At harvest, growth and morphology including fresh and dry mass, plant height and width, and leaf number and nutritional quality including B and C vitamin and carotenoid concentrations were quantified. Post-harvest evaluation was conducted for 3 weeks; fresh mass, color, and nutritional quality were quantified and qualitative appearance data was collected. These results provide insight on how to effectively leverage light intensity, quality, and duration at the EOP to improve the growth and nutritional quality of hydroponic greenhouse-grown spinach.
Funding Source This work is supported by the Agriculture and Food Research Initiative, project award no. 2023-68013-39640, from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.
Livestock and poultry industries have expanded significantly to meet the food requirements of the rapidly growing global population resulting in the generation of almost 1.4 billion tons of manure annually in the United States. To establish innovative approaches to decrease these manure stockpiles, we investigated the potential of using composted manures as effective nutrient-rich amendments for vegetable crops in a controlled environment agriculture (CEA) system. Lettuce (Lactuca sativa L. in the Asteraceae family), one of the most important leafy vegetables, grows well in the field or a CEA system. Furthermore, it can grow under passive or active hydroponic systems. Therefore, in 2024, a project was established to evaluate an innovative solution for the application of composted manures for horticultural crops and their interaction with soil properties in controlled environment conditions in a greenhouse at the Derrickson Agricultural Complex (DAC) at Morehead State University, Kentucky. Three types of composted manures (sheep, cow, and horse) with and without zeolite (crystalline hydrated aluminosilicate) were added in various proportions to a commercial media (Pro-Mix BX All Purpose Growing Mix) and used as the growing media for seedlings of two Romaine lettuce cultivars (Salvius and Amadeus) in six-inch pots, sub-irrigated, and grown until harvesting in the greenhouse. Data on plant morphological and physiological characteristics were collected. The lettuce heads were harvested after two months, and fresh and dried yields were determined. The leaf tissue and media were analyzed for chemical nutrients. The initial results of the first season show significant differences among cultivars and media.
Tomatoes are a highly prized crop all over the U.S, but consumers are seeking more flavorful and high-quality produce. Tomatoes are also popular with growers and consumers in colder regions as well. Short and cold growing seasons provide a significant challenge to tomato production while most breeding and research on tomatoes has been done in warmer climates. In an effort to provide research relevant to growers and breeders in colder regions, this project conducts a germplasm screening of over 80 heart-shaped, indeterminate tomato varieties, many of which were bred in colder regions, in order to provide information on specialty, open-pollinated tomatoes that may be better suited for a shorter season. These tomatoes are characterized by their large size, heart-shape, fleshiness, and fewer seeds. Varieties were obtained from a number of seed catalogs as well as from the USDA Germplasm Repository. In the first year of the project, the varieties were screened for yield, earliness and fruit size measurements as well as dry matter, Brix, pH, and titratable acidity. Genotypes were planted in an augmented design and managed organically in an unheated high tunnel. Based on this year of data, some of the high yielding varieties with the mentioned satisfactory quality traits included ‘German Red Strawberry’, ‘Cuore di Toro’, ‘Russian 117’, ‘Upstate Oxheart’, and a GRIN variety ‘G32329’. None of the varieties exceeded acceptable levels of acidity, but there was much variability in both yield and Brix within the experiment. We also found that a number of varieties categorized as “heart-shaped” were not morphologically heart-shaped. This experiment will be conducted over another growing season in order to collect further data and insights on this project.
Strawberry (Fragaria × ananassa) production has grown significantly in recent decades, increasing demand for specialty crops. Despite improvements in management practices and breeding, maintaining soil health and minimizing environmental impact remain a challenge for agricultural systems. Biochar production and application have been proposed as one effective strategy to mitigate climate change, improve soil health, and promote plant growth. This study, done at the University of Maryland Eastern Shore (Princess Anne, MD), investigated the effect of biochar on the growth and root associated microbial communities of two selected day-neutral strawberries, Monterey and Seascape, under greenhouse conditions. A pot experiment was conducted with three treatments: No biochar (control), 5% biochar, and 10% biochar. Growth parameters including plant height, number of leaves, number of flowers, runner production, and chlorophyll content were measured at 30, 60 and 90 days after transplanting. The 5% biochar treatment enhanced leaf development, runner production, and yield in Monterey, whereas biochar at 10% improved chlorophyll content in both cultivars. The microbial analysis revealed higher Amplicon Sequence Variants (ASVs) with 10% biochar. Cyanobacteria and Proteobacteria were the dominant microbial taxa across all treatments at the phylum level, with no significant differences between biochar treated groups and control. Alpha diversity metrics showed no significant differences (p > 0.05) between treatments, whereas the beta diversity showed a slight shift in microbial community composition in the biochar amendments. A more diverse microbial community was observed in the control group, nevertheless, the biochar amendment demonstrated a more stable and functionally enriched microbiome. These findings contribute to the growing body of knowledge on biochar’s role in optimizing crop production and supporting sustainable farming practices.
As our understanding of the microbiome’s importance to agriculture improves, questions surrounding effective microorganism inoculants as crop treatments continue to arise. These products purportedly increase nutrient bioavailability and enhance plant growth. However, these vary in contents by producer and can be costly, especially given the inconsistent results on their efficacy. Local effective microorganisms (LEM) are alternative formulations produced with local forest litter and carbon sources that can be produced at scale on-site by farmers using local ingredients. LEM application has previously been shown to alter the dynamics of nitrogen availability and soil microbial populations when added to soil amendments, and may influence crop quality and microbial community resilience. However, long-term research on its relevance to organic vegetable rotations is still in its early stages. This project sought to determine the impacts of LEM application on the yield and quality of organic vegetable crops, and to compare soil nitrogen dynamics of these systems to a controlled laboratory incubation. In the field component, a vegetable rotation consisting of kale, carrot, or crimson clover (spring) and green beans (fall) was grown at three different organic farms in the Georgia Piedmont region for two years, and received either a control, low, or high LEM application rate twice per year. Soil samples were taken periodically for inorganic nitrogen, and at harvest total and marketable yields were taken. Subsamples of each harvested plot were juiced and analyzed for sugar content via %Brix. The laboratory incubation was performed on samples obtained from each plot from the field study, which were incubated for 120 days at a standard water content. Each microcosm received either no treatment or an LEM treatment analogous to its respective field plot at time zero. Sulfuric acid traps were used to measure ammonia volatilization, and samples were periodically taken from each microcosm to be analyzed for inorganic nitrogen and pH. At Day 28 of incubation, the average total inorganic nitrogen across treatments was 5.68 ppm. At the end of incubation, the average pH across all treatments was 5.97. The average %Brix for the beans across all locations was 3.5; plants that received high LEM showed higher Brix in plots where crimson clover was the winter crop in two of the three locations, and in plots where kale was the winter crop in one of the locations. These results indicate that LEM may influence produce quality metrics in some common vegetable crops.
Water spinach (Ipomoea aquatica) is classified as a noxious weed by the USDA. However, it remains a popular vegetable in Southeast Asia. Water spinach thrives in warm, moist conditions. Demand for water spinach is increasing in the state of Georgia. The present study assesses the effects of planting date and organic fertilization rate on water spinach yield. The study was conducted in an organically certified high tunnel at the University of Georgia Tifton Campus. Organic fertilizer was applied and incorporated into the soil before planting. Water spinach seedlings were grown in a greenhouse. Within the high tunnel, plants were cultivated on drip-irrigated raised beds (1.8 m apart center to center), covered with white-on-black film mulch. Plants were grown in two rows per bed, with 45 cm between rows and 30 cm between plants. The experimental design was a split-plot arrangement with three replications. The main plots consisted of three planting dates—T1 (16 May), T2 (9 July), and T3 (3 Oct.)—while the subplots included four fertilization rates: 0, 56, 112, and 224 kg/ha of nitrogen (N) applied as organic fertilizer. Plants (shoots) were harvested by cutting 5 cm above the soil surface: four times for T1, three times for T2, and once for T3, with the final harvest conducted on 22 Nov. Shoot fresh weights (FW) were recorded. Results showed that cumulative shoot FW was highest at the earliest planting date (T1; 2.77 kg/m²), followed by T2 (2.36 kg/m²), and lowest at the latest planting date (T3; 0.062 kg/m²). The reduced cumulative shoot fresh weight observed in the latest planting suggests that cooler fall conditions significantly limited plant growth. Regarding the fertilizer rate, the cumulative shoot FW was highest at the 224 kg/ha N fertilization rate (2.03 kg/m²) and lowest at 0 kg/ha N (1.41 kg/m²). However, the relatively high shoot growth at 0 kg/ha N is notable and may indicate the presence of confounding factors. Plants exhibited vigorous shoot and root development, including the formation of adventitious shoots, which likely allowed them to explore soil beyond the experimental plot boundaries (the separation between plots was 30 cm). Visually, plants appeared to grow more actively when provided with ample soil moisture and organic fertilizer. In conclusion, the optimal planting window for water spinach in South Georgia appears to be from April to July. The effect of fertilizer rate on water spinach growth could not be conclusively determined from this study.
Sustainable agricultural practices are essential to mitigating the impact of climate-induced stresses on crop production. Enhancing photosynthetic efficiency is a key strategy to boost yield, productivity, and resilience to stress, especially in organic farming. This study aimed to identify natural variation in leaf photosynthesis and uncover key genetic regulators of physiological and molecular responses in USDA spinach (Spinacia oleracea) germplasm under organic cultivation. 314 USDA organic spinach accessions and commercial checks were planted in an augmented design within an organic field in Uvalde, Texas. Gas exchange traits—including CO2 assimilation rate (A), carboxylation efficiency (CE), CO2 concentration in leaf air spaces (Ci), transpiration (E), CO2 efflux, stomatal conductance (gsw), and water use efficiency (WUEi)—as well as chlorophyll fluorescence metrics such as the efficiency of energy harvesting by oxidized (open) PSII reaction centers (Fv’/Fm’), quantum yield of PSII, electron transport rate, non-photochemical quenching, and photochemical quenching were measured using the LI-6800 portable photosynthesis system. The genome-wide association study (GWAS) was conducted on photosynthesis traits in 299 spinach accessions using 50,873 SNPs. Several SNP markers associated with different traits and candidate genes were identified. Our findings emphasize the value of combining high-throughput photosynthesis measurements with GWAS to reveal the genetic basis of photosynthetic variation in crop species.
Obtaining sufficient nutrients and fighting foliar diseases caused by pathogens such as Alternaria and Cercospora remain an on-going problem for many carrot (Daucus carota) growers. Spraying leaves with mixtures containing soluble nutrient sources and beneficial microbes have potential to help address these issues, but the benefits may depend on the responsiveness of individual carrot genotypes. To test this hypothesis, a field trial was conducted on an organic farm in northern Indiana using three diverse carrot genotypes (Napoli, Nb3999, and Bolero). Each genotype was sprayed with a mixture of four commercial products commonly used by many organic farmers in the area, or left untreated as a control. Soil samples were collected midseason and changes in soil chemical and biological properties were quantified using standard practices. The incidence and severity of foliar diseases was also evaluated visually during the growing season and leaf samples were collected for quantification of leaf microbiomes. At harvest, total shoot and root biomass was determined and carrot taproot samples were collected for analysis of nutritional quality and endophytic microbiomes. Preliminary results indicated that foliar diseases were not particularly problematic during the 2024 growing on this farm. The carrot genotypes varied significantly with respect to above and belowground biomass, however, the treatments did not have any effect on these parameters. There were also no differences in the impact of the foliar sprays on soil parameters, which was expected. We suspect that the lack of any effect of the foliar sprays on carrot biomass was due to the absence of disease pressure at this site, where changes induced in leaf and root microbiomes could have helped mitigate any disease pressure.
Vegetable transplant production is a critical phase that enhances the efficiency, sustainability, and profitability of vegetable cropping systems. In the U.S. Midwest, many organic vegetable growers produce their own transplants due to the limited commercial availability of certified organic transplants. A major constraint in this process is managing nutrient availability, which can compromise transplant quality. While a variety of organic amendments exist, there is limited empirical data on their comparative effectiveness and application strategies in transplant production. This two-year greenhouse study evaluated the effects of selected organic amendments on the growth, root system architecture, and nutritional composition of pepper (Capsicum annuum) transplants grown in 25-cell trays. The experiment was arranged in a randomized complete block design with four replications. Treatments included three dry organic fertilizers bone meal (3-15-0), blood meal (12-0-0), and feather meal (12-0-0) mixed at recommended label rates with growing media at the time of seeding. Additionally, treatments included a liquid fish emulsion (5-1-1 AquaPower™), compost amendment, conventional synthetic (15-5-15 Peters Excel®), and a no-fertilizer control. Data was collected on plant height, stem diameter, plant biomass, tissue nutrient content, and chlorophyll content of leaves. Root and shoot biomass were also collected followed by analysis of root architecture using WinRhizoTM software. Synthetic fertilizer treatment resulted in the highest plant biomass and height, followed closely by blood meal, with no statistically significant difference between the two in either year. Root surface area and volume were greatest in plants treated with feather meal, followed by those receiving blood meal. Weekly EC and pH data collected on the growth medium leachate samples showed that there was a strong negative correlation between them that is when EC was high, pH was low across the treatments, with compost treatment having the highest EC and pH overall. These findings underscore the influence of organic fertilizer source on pepper transplant growth and nutrient status, contributing to improved organic transplant production practices and enhanced transplant quality for vegetable growers.
Tomato (Solanum lycopersicum) growers report that foliar diseases are their biggest production challenge. The tomato organic management and improvement (TOMI) project was launched in 2014 with support from the NIFA-OREI program to address this challenge. We have applied a transdisciplinary approach, integrating studies aimed at 1) increasing biocontrol efficacy, 2) understanding mechanisms controlling induced systemic resistance (ISR), and 3) developing new varieties using a participatory breeding approach. In our biocontrol studies, we learned that combining products with different modes of action was not effective, however, if applied early and often, some biocontrol agents can reduce disease across diverse locations and years. Potting media and composts containing residues with high carbon to nitrogen ratios can increase survival and efficacy of a soil-applied biocontrol agent. In our ISR studies, we learned that not all tomato genotypes are responsive to this form of disease control. The most responsive are wild relatives (Solanum pimpinellifolium), which release distinct compounds from their roots to signal and support soil microbes with biocontrol capabilities. ISR responsiveness is associated with upregulation of brassinosteroid and phenylpropanoid pathways, and grafting appears to promote ISR activity. Identifying genetic markers will improve selection for this trait. Finally in our breeding program, we learned that engaging growers in the selection process aids in the development of new varieties with the most desirable set of traits. We made significant gains in advancing populations and some advanced lines are being considered for release by seed companies, though resistance in many populations is not effective in all ecoregions. Regionally-focused breeding programs are likely to be more effective in developing varieties best adapted to local environmental conditions and disease complexes. We are continuing to work closely with growers to advance these efforts. More information about our project and resources for growers can be found on our website: https://eorganic.info/tomi.
The number of empty houses in South Korea is expected to surge due to rapid population decline. The problem is being overcame through remodeling and leasing in other countries. However, those businesses are not productive and sustainable. Considering climate change and the decline in the agricultural population, we would suggest a project to use empty houses for agricultural purposes. Smartfarm technology allows us to grow crops anywhere, thus farming in the apartments is possible. In particular, since most apartments in South Korea are complexed, large-scale cultivation is possible. We expect economic effect (sales revenue, local food market, job creation, real estate value, distribution process), social effect (connection between cities and rural areas, food security, local communities) and environmental effect (carbon reduction, sustainability, urban green space) from this project. Taking advantage of the characteristics, we believe that it is necessary to proactively conduct a study on a smart value chain system that connects cultivation, storage, retail, and restaurants.
Funding Source Korea Institute of Planning and Evaluation for Technology in Food, Agriculture and Forestry(IPET) and Korea Smart Farm R&D Foundation(KosFarm) through Smart Farm Innovation Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs(MAFRA) and Ministry of Science and ICT(MSIT), Rural Development Administration(RDA)(RS-2024-00400011)
Strawberry harvesting is a labor-intensive task that requires careful, selective picking to avoid damaging delicate fruit. To address labor shortages and enhance harvesting efficiency, we propose an AI-enhanced soft robotic system capable of autonomous and selective strawberry harvesting. Specifically, the system incorporates advanced computer vision algorithms, leveraging the Grounding DINO model, to detect and localize ripe strawberries with high accuracy. A compliant soft robotic gripper, guided by real-time perception, then gently harvests only the target fruits, minimizing potential damage to adjacent berries and plants. Experimental results demonstrate that the system achieves a ripe strawberry detection accuracy of 88% and a harvesting success rate of 66.67%. This integrated approach offers a scalable, precise, and labor-efficient solution for modern strawberry production.
Seed germination may be affected by various abiotic and biotic stressors, resulting in significantly reduced crop yields and resource use efficiency, thus posing challenges to food production for the growing global population. Therefore, several studies have focused on employing diverse mechanical and chemical treatments to improve seed germination. Non-thermal plasma (NTP) is an emerging technology for enhancing seed germination and plant growth. This study evaluated the effects of NTP on the germination properties of borage (Borago officinalis L.) seeds. Plasma was generated using a custom-made surface-barrier-discharge (SBD) device, operating at a frequency of 5 kHz and voltage of 1.3 kVpp. Seeds were exposed to plasma for 0.5, 1, and 2 minutes, whereas untreated seeds served as the control. Each treatment was replicated three times, with each replication divided into two subunits, containing 25 seeds per experimental unit. Germination was monitored under controlled conditions (20 °C temperature, 16 hours photoperiod, 200 µmol/m2/s PAR radiation provided by fluorescent lights and 74% relative humidity) in a PGR-15 Conviron plant growth chamber for 10 days. Germination was assessed daily, and key germination parameters were analyzed, including final germination percentage (GP), mean germination time (MGT), mean germination rate (MGR), coefficient of variation of germination time (CVt), germination index (GI), and time to 50% germination (t50). Plasma treatment for 0.5 and 1 minute significantly (p < 0.05) increased germination percentage (GP) (52 ± 5.37% and 50.67 ± 2.46%, respectively) compared to the control (34.67 ± 3.96%). MGT decreased in all plasma-treated groups, with the shortest MGT (3.94 ± 0.13 days) observed for 0.5 minutes compared to 4.91 ± 0.29 days for the control, suggesting faster germination. Plasma treatment significantly enhanced MGR, with shorter exposure time leading to accelerated germination. All plasma-treated groups reached 50% germination faster than the control, suggesting improved seed vigor. The GI of plasma-treated seeds was consistently higher than the control, indicating greater germination uniformity. These findings highlight the potential of non-thermal plasma treatment to enhance key factors for improved yield and crop resource use efficiency.
Funding Source The research was funded by the Pennsylvania Department of Agriculture Specialty Crop Block Grants No. C940001529 “Developing Plasma Agriculture Solutions to Improve Vegetable Yield and Quality” and was supported by the Strategic Networks and Initiatives Program (SNIP) “Developing the Penn State Interdisciplinary Initiative on Plasma Agriculture”, funded by the Penn State College of Agricultural Sciences. FD's contribution was funded by the USDA National Institute of Food and Agriculture and Hatch Appropriations under Project #PEN05002, Accession #7007517.
Agrivoltaic systems, which integrate photovoltaic (PV) panels with agricultural production, offer potential benefits for sustainable land use but remain underexplored in many regions. A needs assessment survey conducted among stakeholders on the Navajo Nation identified both an interest in agrivoltaics and a lack of understanding regarding its implementation and impacts. In response, a pilot study was established to evaluate the effects of PV panel shading on microclimatic conditions and radish (Raphanus sativus) productivity in a controlled small-scale agrivoltaic system. This study aimed to generate preliminary data to inform future agrivoltaic research and applications. The experiment utilized open-bottomed grow boxes filled with a 2:1 mixture of commercially available peat-perlite growing medium and organic mushroom compost, placed over field soil. Radish seeds were sown under four different PV panel treatments and a full-sunlight control, with environmental parameters—including air temperature and light intensity—monitored throughout a 46-day growth period. At harvest, crop yield and soil characteristics, including nutrient content, electrical conductivity, pH, and heavy metal concentrations, were analyzed. Morphological parameters such as total root biomass and the proportion of marketable roots (≥16 mm in diameter) were also assessed. Results indicated that PV panel shading reduced radish productivity, with shaded treatments exhibiting lower root biomass and yield compared to the full-sunlight control. These findings suggest that shading effects from PV panels may negatively impact radish growth under fall seasonal conditions. This study provides critical baseline data for optimizing agrivoltaic system designs based on crop selection and environmental conditions, contributing to broader research on sustainable agricultural practices in arid and semi-arid regions.
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 →
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 →
Major U.S. apple producing regions include Washington, Michigan, and New York for an aggregate of 10 billion pounds of apples/year. While most apple orchards in the Western region feature irrigation systems, large portions of acreage in the Midwest and Eastern regions rely on rainfall and are sensitive to lengthy dry periods during the growing season. These dry periods have been shown to cause fruit drop and drastically reduce fruit size. Apple rootstocks represent the interface between soil and scion and are a critical component of water relations in orchards. Understanding rootstock response to drought is a key component of securing apple production in vulnerable regions. In this study, we utilized a large format aeroponics system (LFAS) with integrated sensors for light, root moisture, and caliper to conduct an exploratory experiment on the utility of the LFAS to study rootstock behavior during drought in real time. The LFAS contained 12 trees of 6 rootstock genotypes grafted with ‘Honeycrisp’. Each tree was suspended into the LFAS with a collar and the roots sprayed with a pH-balanced nutrient solution at intervals of 30” on/1’30” off. Trees were grown from June-November in a heated greenhouse (24oC) with supplemental lighting. We selected three rootstocks (G.890, G.935, G.969) to monitor before, during, and after drought using LiCor-600 porometer readings. Prior to treatment, we selected four newly expanded leaves at the top of the tree and two mature leaves in the mid-section, labelling them N1-N4 (newer leaves) and O1-O2 (older leaves). Baseline porometer readings were collected at 4:30 AM and then at 12:00 PM under full sun and supplemental light. Subsequently, solution misting was shut down from 12:00 PM to 4:00 PM on November 11th, 2022. In aeroponics, solution film provided by misting and reserve moisture in the roots are all that is available for evapotranspiration. As a result, the drought treatment was almost instant. Roots appeared dry and both apical sections of the trees and mature leaves wilted. After 2 weeks, leaf damage was recorded. Post-drought, N1-N4 and O1-O2 leaves were measured again with the porometer, as well as two “Drought Damaged” leaves (DD1-DD2). Statistical analysis indicated significant Drought*Genotype effects (p < .0001). Dendrometer readings showed the differential response to drought of each rootstock in real time. This experiment demonstrated that aeroponics is a viable method for assessing drought tolerance of rootstock-scion combinations, and showed drought tolerance of the rootstocks was G.935 > G.890 > G.969.
Modern agricultural systems, notably hydroponics, utilize digital technologies and precision farming techniques for automated, sensor-driven cultivation. These systems apply real-time environmental monitoring to enhance plant growth parameters and operational efficiency. Nevertheless, sensor inaccuracies can undermine data integrity due to malfunctions or environmental influences. Thus, this is required to obtain comprehensive environmental analysis and precise data management protocols to maintain system integrity. This study assessed the sensors' reliability by evaluating algal coverage metrics in hydroponic tomato cultivation. A total of one hundred seventeen sensors designed to measure pH, temperature, humidity, and electrical conductivity (EC) were deployed within a greenhouse environment. Following a duration of three months, only 39 sensors were classified into two separate categories: 22 demonstrating considerable algal coverage (≥90%) and 17 exhibiting minimal coverage (~10%). Sensors characterized by high algal coverage recorded substantially increased substrate humidity (85.6% vs. 41.9%) and EC values (774 µS/cm vs. 331 µS/cm) in contrast to their counterparts with lowered algae coverage. However, tomato yields did not significantly change between the two categories, indicating that the plants accommodate the changing environmental conditions. These results suggest that algal coverage may serve as an indirect metric for evaluating localized environmental parameters—particularly humidity and EC levels—and may also hold potential value in assessing the reliability of sensor data.
Funding Source Korea Institute of Planning and Evaluation for Technology in Food, Agriculture and Forestry(IPET) and Korea Smart Farm R&D Foundation(KosFarm) through Smart Farm Innovation Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs(MAFRA) and Ministry of Science and ICT(MSIT), Rural Development Administration(RDA)(RS-2024-00400011)
UAV Remote Sensing for Western Mayhaw Flower Intensity Assessment Presenting Author: Austin Fruge’ Co-Authors: Dr. Cengiz Koparan, Dr. Donald M Johnson, Dr. Amanda McWhirt Abstract. Western Mayhaw (Crataegus opaca) is an emerging economically important fruit in the genus Crataegus due to increased consumption, expanded marketing, and improved cultivars. Further research is needed to expand technology-driven management strategies and investigate its potential as an economical crop for rural and urban landowners in the Southeastern United States. The current methodology for estimating flowering intensity assessment in Western mayhaws is performed with visual observation in the field. However, this methodology is time-consuming, labor-intensive, and subjective. Given the need for a precise methodology for flowering intensity monitoring in Western mayhaws, we developed an open-source image-based phenotyping workflow from Unmanned Aerial Vehicle (UAV) captured images. A subset of Western mayhaw selections were evaluated for blooming intensity during the spring of 2025 in a private orchard near El Dorado, Arkansas. RGB images of Western mayhaw trees during the early flowering stage were collected using a DJI Mavic 3 Enterprise UAV mounted with an RGB digital camera. Each image was processed using an open-source image processing software to estimate the number of flowers. To evaluate the accuracy of this method, the flowering intensity was evaluated through visual flower counting and a visual scale, and compared to image-based flower estimation. Flowering intensity estimated with image segmentation showed a strong correlation with visual flower counting (r= 0.858, p < 0.001), indicating that an increase in visual flower count can be explained with segmented pixel count for any random image. Flower estimation with image segmentation is accurate and provides a standard method, however, it could be time-consuming due to the large image dataset. A semi-automated or fully automated image processing workflow could be developed to increase the efficiency of image processing.
The development of genotypes resilient to abiotic stresses like drought has a pivotal role over the impacts of climate extremes on global food security. Recent studies suggest that modulating the activity of polyamine oxidases (PAOs) in crop species could enhance stress tolerance. Given the limited data on how altered PAOs expression (either overexpression or silencing) affects physiological and anatomical traits that may contribute to plant resilience, the aim of the present study is to investigate phenotypic variability - focusing on leaf structure and function - in tomato genotypes with modified polyamine metabolism under deficient irrigation. Three tomato genotypes were cultivated in a greenhouse, one reference (cv. Moneymaker) and two transgenic lines of the reference genotype with silenced expression of the genes encoding the homologous enzymes SlPAO3 and SlPAO4 of PAO. Two irrigation regimes were applied: Control (100% field capacity, FC) and Drought (20% FC). Following the development of new leaves under drought conditions (long-term acclimation), anatomical features of the leaves and petioles, as well as gas exchange parameters, were assessed. Results showed that, regardless of genotype, water deficit led to a reduction in leaf area, reflecting a decrease in transpiring surface, an adaptation of leaf function under limited water availability. The slpao3 plants, regardless of the irrigation regime, exhibited a smaller total vascular tissue area per petiole cross-section compared to both the reference genotype and the slpao4 plants. However, during acclimation to drought stress, an increase in vascular tissue area was observed only in the slpao3 plants. These findings align with previous studies highlighting the involvement of polyamines in xylem differentiation processes. Long-term acclimation resulted in a reduction in xylem vessel size and an increase in vessel density, irrespective of genotype, indicating an adjustment of hydraulic traits to meet the water demands of acclimated leaves. Petiole vascular characteristics, leaf area, and gas exchange parameters, independent of genotype and treatment, showed strong correlations among them. These results confirm a coordination presence between hydraulic function and photosynthetic response. Further research is needed to clarify how this coordination influences water transport and use efficiency, and to explore whether modulation of PAOs activity could serve as an effective strategy to enhance plant resilience to environmental stresses.
Short-day onions are grown for fresh market in the southern region of the US, and they require around 10 to 12 hours of photoperiod or 12 to 14 hours of nighttime to thrive. These onions tend to produce fewer, thinner layers and have higher moisture contents, making them susceptible to bruising. When short-day onions are harvested by machines, a small percentage of them are damaged and the rest experience bruising during the harvesting process. This leads to a focus on bulb firmness and how it can affect the reduction of bruise damage. The current study seeks to identify bulb characteristics that affect bulb firmness and their relation to the overall bruise damage in short-day onions. For this, early and main season maturity varieties were used and several bulb characteristics including bulb weight (gm), height (cm), width (cm), number of rings, firmness, growing point (single versus multiple centers), and total soluble solids (°Brix) were measured. Correlation among bulb traits was analyzed using correlation in R corrr package. In the early season, there was correlation between bulb weight and bulb width (r=0.920343), firmness and single center (r=0.504853), and single center and ring number (r=0.609349). There was no significant correlation between bulb firmness and the remaining bulb traits. A negative correlation was observed between firmness and moisture content (r=- 0.412323) and firmness and ring number (r=- 0.5084) in the main maturity season trial, but not enough to significantly impact the bulb firmness. The results suggested that in early maturity bulbs, a single center directly correlated with firmer bulbs, but in the main maturity season, firmness had a negative correlation with moisture content and ring number. Results will be validated with the second season trial during the 2024-2025 season.
Orange-fleshed sweetpotato (Ipomoea batatas) cultivars with moist, sweet texture are the most popular type of sweetpotatoes grown in the United States, while elsewhere in the world, white, yellow, and purple-fleshed types with firm, dry texture are more popular. There is a market opportunity in the United States for diverse sweetpotato cultivars, however, their yield tends to be low as they have not received the same breeding attention as orange-fleshed cultivars. In this experiment, six advanced breeding lines from the USDA, representing a diversity of flesh colors, textures, sweetness, and firmness, were compared to cvs. Covington (standard) and Cascade (new release). The experiment was carried out in a certified organic field in Mount Vernon, WA in 2024 and is being repeated in 2025. Each plot included 15 plants with 4 replicate blocks. In 2024, sweetpotatoes were planted on 4 June in raised beds covered with black polyethylene mulch and with drip irrigation. Harvest was by hand on 7 Oct., roots were sorted by size, and damage by wireworms (Agriotes lineatus, A. obscurus, Limonius canus), the most significant insect pest impacting sweetpotatoes in this region, was assessed using the WDS severity index ( 0 = no scars, 1 = 1-5 scars, 2 = 6-10 scars, 4 = >10 scars). Without accounting for wireworm damage, yield (US No. 1 and US No. 2) of ‘Covington’ (orange, soft flesh) was highest (18.2 t/ha) followed by USDA-22-009 (13.8 t/ha, yellow flesh), and ‘Cascade’ (white, firm flesh) had low yield (6.7 t/ha) followed by purple-fleshed breeding lines USDA-17-090 (4.1 t/ha) and USDA-16-051 (3.1 t/ha). Orange-fleshed breeding lines USDA-16-031 (3.8 t/ha) and USDA-19-036 (1.7 t/ha) and yellow-fleshed USDA-23-039 (0.5 t/ha) all had low yield. ‘Cascade’ was the most wireworm resistant (WDS severity index 1.61) followed by USDA-16-051 (2.33), while ‘Covington’ and USDA-22-009 were the most susceptible (3.67 and 3.54, respectively). The breeding lines USDA-16-031, USDA-17-090, USDA-19-036, and USDA-23-039 had similar ratings, ranging from 2.83 to 3.39. While yields of ‘Cascade’ (white, firm flesh) and USDA-16-051 (purple flesh) were less than ‘Covington’, farmers may be interested in growing these niche cultivars for their wireworm resistance and to cater to consumer interests.
Garlic (Allium sativum) is a cool season and flavorful vegetable crop that has a long history in culinary, horticultural, medicinal uses. Oklahoma is a state characterized by diverse weather and soil types, but there is an economic opportunity for garlic production with optimal planting techniques and planting recommended cultivars. The number of farmers producing garlic increased from 28 to 44 between 2017 and 2022. This trial was conducted at the Cimarron Valley Research Station with Oklahoma State University in Perkins, Oklahoma and evaluated ten cultivars grown using drip tape irrigation, no mulch, and a no-spray approach to weed and pest control. Total graded marketable yield and allicin content were recorded during the 2023-2024 and 2024-2025 growing season for softneck and hardneck cultivars including: ‘California Early’, ‘Chesnock Red’, ‘Duganski’, ‘German Extra Hardy’, ‘German White Stiffneck’, ‘Inchellium Red’, ‘Music’, ‘Purple Glazer’, ‘Romanian Red’, and ’Sicilian Artichoke.’ In 2024, the top performing cultivars were ‘German Extra Hardy’ and ‘Inchellium Red’. These were significantly higher yields that ‘Duganski’. No other statistical differences were observed. Their respective marketable yields were 2,704 and 2,538 pounds per acre. In addition, we recorded allicin content for each cultivar using a spectrophometric assay. Allicin is one of the most important thiosulfates in garlic and its presence adds market value for those interested in the nutritional and health benefits of garlic. We observed statistically significant differences among the cultivar entries. ‘California Early’ and ‘Duganski’ had a significantly higher allicin content at .66 grams and .59 grams per 100 g sample than ‘German White Stiffneck’ at .49 grams per 100 g sample. Additional research of allicin content among different cultivars of garlic is needed to guide consumers and healthcare professionals in selecting the best cultivar for fresh market consumption.
Broccoli, scientifically known as Brassica oleracea var. italica, was first cultivated in the 17th century. Based on 2022 USDA Ag census, in the United States, broccoli is grown on 96,600 acreage. Broccoli is damaged by more than 25 insect pests. Some pests are region/place specific and some are common across the world like aphids, mites, etc., Pests like imported cabbage worms, cabbage loopers, and diamondback moths have a destructive effect on the crop in different growth stages of the crop. Organic pesticides to manage these pests have mixed results and account for increased labor and costs. Mesotunnels could serve as a viable pest management approach within organic production systems. “Meso” means “middle,” so mesotunnels are medium-size tunnels – taller than low tunnels and shorter than high tunnels. A breathable nylonmesh fabric (brand names include ProtekNet and ExcludeNet) that resembles window screen are placed over the mesotunnel. The fabric acts as a barrier for insect pests and prevents their entry and disease-carrying pathogens. These nylon nets are breathable, durable, and light permissible which can also protect from extreme weather conditions like hail damage. This study includes the following three treatments: 1) Mesotunnel with proteknet, 2) Organic insecticides, and 3) Control (no mesotunnel or organic insecticides). Mesotunnel treatment resulted in less pest damage (No.of holes/plant) with a mean 14 when compared to organic insecticides which had mean damage of 22. A significant difference was observed in pest damage between the treatments. Regarding marketable yield, the highest was observed in the Mesotunnel treatment. However, no significant difference was found between the treatments. This study aims to identify the most effective method of pest management in broccoli production while minimizing the environmental impact through reduced reliance on pesticides. Keywords: mesotunnels, proteknet, excludenet, organic pesticides
Matching breeding target with consumer preference is the goal of many crop production methods. But this is normally a difficult challenge when the selected disease- and pest-resistant materials do not meet the consumers’ product preference. In this report, we highlight the efforts we are making to deliver cucumber lines with consumer-preferred visual traits and that have combined resistance to melonworm, leaf miner, aphids, and Downy mildew. After a series screening of 100 lines from the USDA, 36 showed at least 40% resistance to leafminer and melonworm in 2022 and 2023. Of these, we have evaluated 16 against lines with varying degrees of resistance and six susceptible lines against three commercial varieties commonly grown in the Virgin Islands. All the 25 cucumber lines were exposed to open natural infestation by leaf miner, melonworm, aphids and downy mildew in the open field and scored for resistance based on visual ratings designed for each infestation. We used a mathematical model that considered multiyear and multilocation performances to rank the lines for combined resistances. Unfortunately, the top three resistant lines were not among the top five visually appealing fruit types on a consumer preference scale based on a survey of 245 respondents. We report on the prospects and anticipated timeline for the development of cucumber plants with the preferred fruit type and disease and pest resistance traits. Our study has the potential to deliver cucumber varieties that are highly adapted to the Caribbean abiotic and biotic stresses and that have significantly reduced pesticide footprints. Key words: Consumer preference, cucumber, pest resistance, screening, trait
A greenhouse culture system simulated in-ground curing by imposing pre-harvest water deprivation treatments in sweetpotato. Virus-tested sweetpotato cv ‘Beauregard’ cuttings were planted at the following staggered times relative to the control (0d): 10 days (10d) and five days (5d) earlier, respectively. Water deprivation treatments were applied 10d and 5d pre-harvest. The first study terminated experiments when the control plants attained 30 days of growth. Storage root sections 1-2 mm thick were obtained from the broadest part of the storage root, stained with phloroglucinol, followed by image capture with a microscope. Digital image analysis was performed by measuring the area of the continuous lignified zone (CLZ) below the phellogen layer and calculating % CLZ after measuring the total area of the cross-section. Simulated WD at 10d and 5d was associated with a six- and three-fold increase in % CLZ, respectively. None of the control SRs showed 100% CLZ, while 50% of SRs subjected to 10d WD showed an intact ring of lignified tissue below the phellogen layer. Storage roots from control plants consistently showed breaks in the phellem tissue relative to SRs subjected to WD treatments. In the second study, plants were grown for up to 50 days, and harvested SRs were kept in ambient conditions for weight loss measurements. Water deprivation was associated with reduced weight loss in SRs relative to SRs grown in well-watered conditions. These findings can lead to follow-up work to validate increased skin durability with pre-harvest, in-ground curing in production areas where postharvest curing facilities aren’t available.
No roots left behind! The sweetpotato's root system architecture integrates internal, environmental, and management determinants of storage root yield, quality, and shape attributes. Root architectural adaptations to biotic and abiotic stress variables provide insights about traits... Read More →
Sweetpotato (Ipomoea batatas) is a tuberous root crop and an important agricultural staple in the U.S. Virgin Islands. Due to its year-round production potential, drought tolerance, adaptability to calcareous soils, and cultural significance, a more efficient land-use and cropping system is needed. The objective of this study was to investigate the impact of sweetpotato cutting length on yield per linear foot on five cultivars, ‘Bonita’, ‘Bellevue’, ‘GA-11’, ‘Murasaki’ and ‘Sakura-40’. Actively growing vines from five cultivars were propagated using 6–8-inch terminal cuttings and 3-foot cuttings. An 8-inch drip irrigation system was used for both treatments. After 130 days, harvest data were collected on number of tuberous roots, weight, and marketable yield. Results showed that Bonita, Bellevue, and Murasaki produced higher yields (kg/ft) when planted with 6–8-inch cuttings, whereas ‘GA-11’ and ‘Sakura-40’ yielded more with 3-foot cuttings. Similarly, ‘Sakura-40’, ‘Bonita’, and ‘Bellevue’ had greater numbers of marketable and total roots per foot with 6–8-inch cuttings, while ‘Murasaki’ and ‘GA-11’ performed better in both categories with 3-foot cuttings. These findings indicate that optimal cutting length is variety-specific, with certain cultivars favoring shorter cuttings for higher yield and root number, while others benefit from longer cuttings. This research was funded by a USDA Mutistate Hatch Grant.
In the northeastern US, cold-tolerant crops such as spinach are an important source of winter income for high tunnel growers. Supplemental rowcovers are used on crops inside unheated high tunnels to expose plants to optimal temperature ranges for longer periods of each day and to provide greater protection from injurious low temperatures. Rowcover management impacts temperature, light availability, humidity, pest populations, crop yield, and labor requiremenst. Some growers actively manage rowcovers, removing them daily to optimize light exposure and then reapplying them in the evening and on cloudy or very cold days. This is thought to provide a yield benefit due to increased crop light availability, but it is labor intensive and experienced growers often make decisions about removal based on a combination of current conditions and forecasted weather. Therefore, some growers opt for a “set it and forget it” approach, where layers are applied once and then only removed as needed, rather than daily. Here we describe the tradeoffs of “active” rowcover management, where rowcovers are removed during the day and replaced nightly, compared to “passive” management, where rowcover is removed only for harvest and regular maintenance. We conducted a replicated trial in two experimental years in an unheated high tunnel to investigate the effects of rowcover management on winter spinach yield, pest abundance, and abiotic environmental factors including growing degree hour accumulation. We also compared our observations with those from commercial tunnels managed by three experienced growers in the northeast. In both experimental years, growing-degree hour accumulation and the cumulative amount of time below freezing did not differ significantly between active and passive management. However, active rowcover management did result in greater light accumulation, lower relative humidity, and increased spinach yields in one experimental year compared with passive management.
Seagrass that washes ashore is an abundant, traditional amendment for crop production on Yap Islands, yet its potential for modern sweetpotato (Ipomoea batatas) cultivation remains largely unexplored. Traditionally, semi-decomposed seagrass is incorporated to create raised beds where sweetpotato is grown for several years. While compost and manure can be effective amendments to improve the conditions of the highly weathered, acidic volcanic soils of the Yap Islands, they are costly, labor intensive, and in short supply. By utilizing an abundant, free resource, this project seeks to improve crop yields and extend the productive life of agricultural lands. This study includes two field experiments that compare semi-decomposed seagrass with conventional commercial fertilizer for two sweetpotato cultivars in two production systems, raised-beds and grow-bags. Experiment 1 utilizes raised beds established on three farm sites with an improved sweetpotato cultivar, where treatments include medium and high application rates (by weight, approximately 40 and 60 kg N ha-1, respectively) of semi-decomposed seagrass and a control treatment using commercial fertilizer (10N-20P-20K) at N rate equivalent to the medium seagrass application. Each treatment is randomized in a complete block design, with six replicates per treatment. Experiment 2 is a split-plot design and compares a traditional vining and a modern sweetpotato cultivar (main plot treatment) in container cultivation using 10-gallon grow bags filled with a soil mix amended with seagrass at medium and high ratios compared to a commercial fertilizer control at N rate equivalent to the medium seagrass application (split-plot treatment). For both experiments, the seagrass is collected, washed, and piled to reduce salinity to acceptable thresholds, with leachate EC measured weekly. Seagrass is then shredded and piled to accelerate decomposition. Analysis results of semi-decomposed seaweed are 15% dry weight with 1.8% N on average, and application rates are 21 g and 32 g per sq foot of soil for N application rates of 40 and 60 kg.ha-1, respectively. Community buy-in and trust building are being achieved through collaboration with island-based agricultural educators and meetings with traditional leaders. This research has the potential to enhance sweet potato production on the Yap Islands, improve resource management, and provide an affordable soil amendment option for local farmers. The project promotes environmental stewardship and contributes to cleaner shorelines and sustainable agricultural practices. The findings will offer critical insights for local agricultural educators and policymakers in optimizing land use and advancing low-cost, high-yield cultivation methods in resource-limited settings.
American elderberry (Sambucus nigra subspecies canadensis) is native to much of North America. The fruit are soft, small, intensely purple drupes, containing three to five seeds. Berries exhibit some anti-viral properties and were found to slow the progression of dementia in animal studies. European elderberries (Sambucus nigra subspecies nigra) have long been used to make phytochemical-rich value-added products, in contrast to the underutilized American subspecies. American elderberry offers potential for products with more color stability as the berries have more cyanidin-3-sambuboside-5-glucoside and acylated anthocyanins than European elderberry. Developing innovative, cost effective, concentrated and portable products such as powders are desired for creating value added products. Successful microencapsulation of elderberry into powders was achieved by spray drying elderberry juice or pomace extract with soy protein isolate or tapioca starch as drying carriers. Anthocyanin profiles in the encapsulated powders were similar to those in juice but concentration was increased by 3-fold. Acylated anthocyanins made up 77% and cyanidin-3-sambuboside-5-glucoside, 17% of the total anthocyanins. Flavonoids delivered in powders encapsulated with soy protein concentrate were doubled in bioaccessibility compared to juice. Fermentation of juice with Saccharomyces cerevisiae yeast decreased soluble sugars and increased spray drying efficiency 20-25%. Fermented elderberry juice spray dried with pea protein or yeast as drying carriers showed increased phenolic content and bioaccessibility. This production strategy offers an efficient way to deliver stable, phytochemically enriched, value-added products from American elderberry for multiple food applications.
Penelope Perkins-Veazie, PhD, is a horticulture professor at the Plants for Human Health Institute. She studies postharvest physiology, which evaluates the best ways to keep fruits and vegetables edible after harvest. Her work includes measuring phytochemicals in produce at various... Read More →
Texas has a strong history in fruit crop production, supported by its range of climates, soil types, and a long record of innovation. Grape growing began in the 1600s with Spanish missionaries and became globally important thanks to T.V. Munson, a horticulturist from Denison, Texas. His work in rootstock breeding helped save European vineyards during the phylloxera crisis. Today, Texas is a major producer of grapes, as well as pecans, peaches, citrus, and many small fruits. These crops all face challenges related to extreme weather events, soil conditions, and long-term sustainability. To help address these issues, the Horticultural Crop Physiology program at Texas A
Dr. Rossi’s research program focuses on understanding the responses of horticultural crops to environmental stresses, with the goal of developing environmentally sound and effective management strategies. He is a horticulturist with expertise in plant stress physiology, plant biology... Read More →
The table grape cultivar ‘Concord Seedless’ is adapted to the northeastern U.S., but small berry size, poorly filled clusters, shot berries, and low marketable yields has hindered its’ commercial potential. Gibberellic acid (GA3) is a plant growth regulator widely used in viticulture to reduce fruit set and to increase cluster length, cluster weight, and berry weight, but effects vary depending on cultivar, application timing and rate. We evaluated the effects of GA3 on cluster quality in ‘Concord Seedless’, a cold-hardy table grape cultivar, grown using two training systems: Munson and Vertical Shoot Positioning (VSP). Field experiments were conducted in 2023 and 2024 at the UNH Horticultural Research Farm in Durham, NH. Treatments included four concentrations of GA3 applied pre-bloom (0, 21, 42, and 63 mg/L) and one concentration post-bloom (0 and 50 mg/L), in a 4 × 2 factorial arrangement. A split-plot design with four blocks was used, with training system as the main plot and GA3 treatments as subplots. The experimental unit for sub plot was two adjacent shoots; all treatments were applied on a single vine. We measured cluster weight, frequency of shot berries and thinned berries, and percentage of clusters exhibiting curling. We hypothesized that pre-bloom GA3 application would result in cluster elongation and that post-bloom GA3 application would increase cluster and berry weight. We also hypothesized that GA3 application at either time would reduce the incidence of shot berries. Results showed significant year × GA3 interactions. In both years, cluster weight was higher in Munson than in VSP-trained vines, but there was a significant interaction between training systems and GA3 treatments in 2023. VSP-trained vines had a higher frequency of shot berries and thinned berries in both years, but the effect was not significantly different. In both years, pre-bloom GA3 applications reduced cluster weight and induced cluster curling and excessive berry thinning, which made clusters unmarketable. In 2023, post-bloom application (50 mg/L) increased cluster weight, and did not cause berry thinning or cluster curling in either training system. Our findings suggest that a single application of post-bloom GA3 when berries are 6 to 9 mm in diameter can improve cluster quality in ‘Concord Seedless’ under cold-climate conditions.
Aronia berry, also known as chokeberry, are rich in antioxidants that promote cardiovascular health, immune function and overall well-being. Beyond their nutritional benefits, they also serve as attractive ornamental landscape plants, providing wildlife provisioning and contributing to ecosystem services. However, not much is currently known about the plant growth and fruit quality of aronia berry in the southeastern US, and how different regions may affect plant growth characteristics. The main objective of this study was to establish plantings in two locations in Georgia and assess native aronia species for plant growth and fruit quality characteristics. The growth and yield of two native species, black chokeberry (Aronia melanocarpa) and red chokeberry (Aronia arbutifolia), were assessed during the 2024 growing season at two agroecological regions in Georgia: Blairsville (Zone 7a, Blue Ridge region) and Griffin (Zone 8a, Piedmont region). Field plots, consisting of three-year-old plants, were established at both locations in 2021. Plant measurements included: growth index, stem diameter at 100 cm height, yield (kg), berry size of the equator (mm), berry weight (g), dry berry weight (g), total soluble solids (°Brix), pH, and total titratable acidity (%TTA). Black chokeberry exhibited significantly higher values (p ≤0.05) for growth and yield in Blairsville than in Griffin. Total soluble solids were not different across locations. Similarly, red chokeberry had higher growth index, stem diameter, and yield in Blairsville, yet location had no effect on berry weight. Individual berry size was not affected by location for both black and red chokeberry. These findings suggest that even within adjacent eco-regions, aronia species show different growth and berry production, and that plants grown in northern regions exhibit larger size and bear more berries. This has implications for ornamental landscapes and restoration habitat practices. This work will be used as part of a larger work to examine the potential of aronia as an alternative fruit crop in the southeast.
The integration of solar energy production with agriculture, known as agrivoltaics, presents a promising solution to address land-use competition while boosting perennial crop productivity. This study evaluated the feasibility and impact of agrivoltaic systems on strawberry (Fragaria × ananassa) production in Iowa. The objectives included assessing plant growth, fruit yield and quality, microclimatic modifications, and economic viability under photovoltaic (PV) panel shading. We hypothesized that partial shading from PV panels would mitigate heat stress, reduce water demand, and enhance fruit quality without significantly compromising yield. A replicated field trial of two June-bearing strawberry cultivars in 2024 and 2025 compared plants under a standard rotating 5-ft PV configuration with traditional open-field production. Environmental parameters such as light intensity and temperature were monitored to quantify microclimatic changes. Additionally, plant physiological responses and post-harvest disease incidence were analyzed. Future economic assessments will determine profitability and trade-offs associated with energy co-production. Findings from this research informed best management practices for integrating agrivoltaics in specialty crop production, particularly in temperate regions. In 2024, berries were larger in weight and size under the panels compared to the open-field plots. Post-harvest assessment indicated that the increase in size did not correlate with a reduced shelf life. Overall, this study found a favorable effect of intermittent shading on strawberry production in the Midwest.
This study presents the outcomes of the NE-SARE Professional Development Program, which was designed to enhance the capacity of farmers and agricultural service providers in the area of nutrition management for June Bearer (JB) and Day Neutral Strawberry (DNS) cultivars. Through seven targeted workshops including the UMES Small Farm Conference and the NE-SARE workshop on fertilizer strategies participants gained practical skills in fertilizer injector use, dose calculations, and the benefits of liquid vs. granular fertilizers. A total of 87 participants attended, with 82 identifying as Black and 46 as women. Key innovations included the distribution of over $7,000 worth of strawberry plants, overcoming access barriers for small-scale and BIPOC growers. Educational sessions transformed participant confidence, with post-survey data showing a shift from 40% reporting "no knowledge" to 70% achieving "advanced" proficiency in nutrition management. Participants reported the ability to perform fertilization calculations, use injectors, and understand fertilizer types. These workshops promoted sustainable practices by encouraging injector-based applications to reduce nutrient loss and pollution. This initiative not only advanced technical knowledge but also equipped growers to make environmentally sound, cost-effective decisions tailored to their operations. The outcomes reveal increased regional engagement and strengthened capacity among underserved farmers, empowering them to adopt sustainable techniques in strawberry cultivation on the Delmarva Peninsula.
Growing southern highbush blueberries (SHB, Vaccinium corymbosum interspecific hybrids) in Florida’s sandy soils presents significant challenges due to their low water retention and limited fertility. Milled pine bark is a widely used soil amendment for SHB cultivation, as it enhances moisture retention, nutrient-holding capacity, soil structure, and maintains an optimal pH (approximately 4.0–5.0) for the crop. However, the physical and chemical characteristics of pine bark, particularly its decomposition dynamics within the SHB rhizosphere, remain poorly understood. This study investigates how pine bark decomposition affects SHB plant growth and productivity. SHB cultivars ‘Optimus’ and ‘Farthing’ were grown in raised beds amended with either aged or fresh pine bark. Plants were irrigated and fertigated via a drip system following commercial production practices. Beginning in June 2024, we measured plant volume, vertically projected leaf area, leaf nutrient concentrations, and yield. In addition, soil and pine bark samples were collected and analyzed. Our findings indicate that plants grown in aged pine bark produced greater above-ground biomass and exhibited higher macronutrient concentrations than those grown in fresh pine bark. The carbon-to-nitrogen (C:N) ratio differed between treatments at the start of the experiment, but fresh pine bark has changed more than aged pine bark since the start of the experiment. These results suggest that fresh pine bark may immobilize nutrients in the SHB rhizosphere, limiting plant growth. A deeper understanding of pine bark decomposition in SHB farms will support the development of sustainable fertilization strategies and improve long-term plant health and productivity.
Blueberries (Vaccinium species) belong to the Ericaceae family and are recognized for their antioxidant content and associated health-promoting properties. A key challenge in blueberry production is their asynchronous ripening with fruits on the same plant often maturing at different times. This leads to multiple harvests, increased production costs, and reduced overall fruit quality. Fruit ripening is a coordinated process wherein there is an increase in sugar concentration, decrease in acidity and accumulation of pigments such as anthocyanins. Blueberry fruit are classified as exhibiting atypical ripening behavior with an increase in respiration and ethylene during ripening. However, ethylene production is not autocatalytic and is under developmental regulation. Previous work from blueberry and other fruits have suggested a role of other hormones such as abscisic acid (ABA), auxin and jasmonates in fruit ripening. In this study, the cultivar Powderblue (Vaccinium ashei) was used to characterize the progression of ripening across multiple tissue types and developmental stages by examining the expression of key ripening-related genes. Fruits were harvested at five developmental stages including ripening. Ethylene was measured from these fruits to identify the stages that coincided with ripening initiation. For each stage, 9 tissue types were collected via dissection to obtain spatial resolution. RNA will be extracted from these tissues for qRT-PCR analyses to determine the expression of a focused-set of ripening related genes. For this study, a total of 37 genes were selected based on a previous RNA-Sequencing study that displayed a differential pattern in their transcript abundance during ripening. A subset of these genes is related to sugar, acid, anthocyanin, phenylpropanoid, photosynthesis, and cell wall metabolism. Further genes related to phytohormone metabolism related to ethylene, ABA, auxin, and jasmonates were included. Also, genes belonging to the NAC and MADS-box family of transcription factors were included. Based on the gene expression analysis, hormones including ABA, auxin and jasmonates will be quantified from a subset of these samples. This study will provide insights into the spatial context of molecular and hormone regulation. The knowledge from this study may help breeding programs aimed at developing cultivars exhibiting synchronous ripening, and the potential development of growth regulators to control ripening in the field.
