ASHS 2024 Conference

Watermelon Rootstock Variety Trial to Understand the Impacts of Grafting on Watermelon Yield and Fruit Quality - Fayrouz Buojaylah
Effect of Biofungicides Containing Trichoderma and Grafting on Watermelon Productivity and Plant Health - Fayrouz Buojaylah
Canary Melons Cultigen Yield and Quality Evaluations in North Carolina, 2023 - Jonathan Schultheis
Watermelon Cultigen Yield Response to Fusarium oxysporum f. sp. niveum Incidence in North and South Carolina, USA - Stuart Michel
Effect of Biostimulants on Field Grown Watermelon (Citrullus lanatus) under Deficit Irrigation and Fertility. - Evan Christensen
Development of the winter artichoke production system in a subtropical climate - Shinsuke Agehara
Globe Artichokes - Variety Trials for Florida Production and Marketing Evaluations - Evelyn Fletcher

In California, watermelon grafting has been gaining tremendous popularity over other graft-eligible vegetable commodities especially among large-acreage growers. To maintain viability and continued popularity of grafted watermelons in California, we conducted a watermelon rootstock variety trial in 2023 to evaluate the impact of different types of locally popular rootstocks on watermelon yield and quality. Seven watermelon rootstocks, grouped into three distinct types: Interspecific hybrid squash (Cucurbita maxima x Cucurbita moschata), Citron (Citrullus amarus), and Bottled gourd (Lagenaria siceraria), were grafted with a 45-ct field scion, ‘Warrior’ by a commercial greenhouse located in Mills River, NC. All grafted and non-grafted seedlings were then mechanically transplanted into a commercial field near Modesto, CA on 19 April 2023. The trial was arranged as a randomized complete block design with four replications for each treatment. Each plot was 24 m long and contained 13 triploid plants, either grafted or not, alongside four grafted or non-grafted pollenizers. Four harvests were conducted from 25 July to 17 Oct with the help of farm crew. Total yields at each harvest and fruit quality from the first harvest were recorded and compared among rootstock-scion combinations. For quality assessment, fruit length and width were measured with a yardstick. Sugar content (ºBrix) was measured by scooping the central flesh of each halved fruit using a portable reflectometer. Flesh firmness was evaluated using a fruit penetrometer, with measurements taken at spots located one-third and two-thirds of the distance from the blossom end after halving the melon. Rind thickness at the blossom and stem ends were measured using a digital caliper. The overall impact of grafting resulted in an average increase of total yield by 51.5% compared to the non-grafted control (54.7 vs. 36.1 tons per acre) with the most significant difference occurred at the second harvest (27.0 vs. 14.8 tons per acre). Differences of fruit quality between grafted and non-grafted watermelons were primarily observed for fruit firmness. The significant increase of firmness (4.9 vs. 3.4 kg.cm-2) for grafted fruit was also confirmed based on the results of taste sensory evaluation. Slight increases of fruit width and stem end rind thickness after grafting were also found. No changes of ºBrix after grafting were detected. Overall, grafting has proven to be a reliable method for enhancing watermelon yield and maintaining fruit quality in California. Continuous needs assessment will be performed to monitor any pressing issues of watermelon grafting in California.

The goal of the project is to evaluate the potential of reducing chemical fumigation in California's watermelon production using grafting and Trichoderma-based biofungicide. Two field experiments in 2022 and 2023 were implemented within commercial watermelon fields in Stockton and Modesto, CA. Each trial included three rootstocks (Cobalt, Flexifort, and RS841) grafted onto a 45-ct scion (Summer Breeze). Two Trichoderma-containing products were applied to the grafted and nongrafted seedlings through tray soaking at one day before transplanting or field chemigation at 30 and 62 days after transplanting (DAT). The application rates for soaking and chemigation were 45 g.75 L-1 of water and 2.2 kg.ha-1, respectively. All seedlings were mechanically transplanted during mid-May of both years into a split-split plot design with the Trichoderma product as the main factor and application method as the sub-plot. All treatments were replicated four times. Each treatment row was 18.6 m long and contained ten grafted or nongrafted triploids and three grafted or nongrafted pollenizers. Vine health was visually assessed three times for symptoms associated with soil-borne fungal pathogens. Canopy coverage was measured starting at 22 DAT in 2022 and 40 DAT in 2023 and thereafter at an approximate interval of two weeks for a total of six measurements. Harvest was conducted three times in 2022 and twice in 2023 to analyze yield and quality differences among treatments. Runner and root samples were taken amid the harvest and shipped to the UC Davis Fungal Pathology Lab for further identification. Results indicated that the Trichoderma-containing bio-fungicides were not as effective as grafting on preventing vine decline and maintaining canopy coverage in both trials. The synergistic effects of grafting and Trichoderma inoculation provided some but limited benefits to plant health compared to the single factor of grafting. The overall influence of biofungicides on yield was also less notable than that of grafting regardless of application method. For fruit quality, grafting dominated the impacts over biofungicides on fruit firmness and rind thickness in both trials. Charcoal rot (Macrophomina phaseolina) with other putative co-infestations of Fusarium pathogens were diagnosed from nongrafted inoculation-free plots in 2022 while no significant soil-borne diseases were identified from 2023. Overall, grafting with multi-pathogen resistant rootstocks prove to be a reliable method for enhancing watermelon yield while maintaining crop health. More work is still needed to further explore the optimal application protocols tailored to grower’s farming system to maximize the effects of biofungicide.

Canary melons, Cucumis melo var. inodorus, are grown in the United States, with most acreage produced in California and Arizona. There is very limited production acreage in the southeastern United States, including North Carolina. No statistics are gathered by USDA on canary melons as this type of melon is truly a specialty melon. The goal of this study was to determine how well adapted canary melon cultigens are with respect to yields and quality when grown in North Carolina and to gauge the possibilities of producing this crop as a commercial option in the state. Fourteen cultigens were evaluated from eight different seed companies for yield and size over 16 harvests, flesh firmness and sweetness, and shape and rind characteristics. Statistical design was a randomized complete block with four replications and mean separation across measures was conducted using a LSD test at the P

Fusarium wilt of watermelon, caused by the soilborne pathogen Fusarium oxysporum f. sp. niveum (FON), is a major disease impacting the watermelon industry. FON can severely reduce yields and is easily dispersed. Cultivar resistance is a desired control strategy due to high fungicide and grafting costs. In 2021 and 2022, triploid watermelon cultivars were evaluated at two locations (Clayton, NC and Charleston, SC) for their tolerance to FON. Eight common cultivars were evaluated for disease incidence and yield at both locations in both years. In 2022, two unreleased cultigens were also evaluated at both locations. All studies used a randomized complete block design with four replications. ‘Fascination’ grafted to ‘Carolina Strongback’ rootstock was included as a control each year. Disease incidence was measured every week starting three weeks after transplanting and until the first harvest at each location. Fruit weights and counts were taken to measure yield. In 2021, ‘Fascination’ had the lowest disease incidence at 75% in NC and ‘Embasy’ had the lowest incidence at 15% in SC. ‘Joy Ride’ had 100% incidence in NC and ‘Shoreline’ had the highest incidence in SC at 68%. Yields correlated with disease incidence with ‘Fascination’ having the highest yield of the ungrafted treatments in NC with 17,878 lb/ac (pounds per acre) and ‘Embasy’ with 22,687 lb/ac in SC. ‘Shoreline’ was the lowest yielding at both locations with 6,556 lb/ac in NC and 5,376 lb/ac in SC. The grafted ‘Fascination’ treatment had the lowest disease incidence and the highest yield at both locations in 2021. In 2022, the unreleased cultigen HMC633802 had the lowest disease incidence at both locations with 50% in NC and 51% in SC. Of the eight common cultivars, Fascination had the lowest incidence in NC at 83% and El Capitan had the lowest in SC at 52%. ‘Shoreline’ had the highest incidence at both locations with 100% in NC and 94% in SC. Yields correlated with disease incidence. Unreleased cultigen HMC633800 had the highest yield of the ungrafted treatments in NC with 15,575 lb/ac and Powerhouse had the highest yield in SC with 27,243 lb/ac. The grafted ‘Fascination’ treatment had the lowest incidence and highest yield at both locations in 2022. The cultigens we evaluated provided minimal tolerance to FON in both years.

The impacts of climate change and drought threaten water supplies crucial for watermelon production. Rising fertilizer costs and off-site effects also pose problems for the sustainability of watermelon production. Biostimulants shown promise in helping plants maintain production under deficit irrigation conditions and may offset fertility addition through ecosystem services and stimulatory effects. In this study two watermelon cultivars (Crimson Sweet and Fascination) were treated with three biostimulant products (Mighty Mycorrhizae, Spectrum DS, and Continuum) and then subjected to reduced fertility (67% of recommended rate) and irrigation (75% evapotranspiration). Raised beds covered in plastic mulch were used with rows spaced 1.83 meters apart and plants 0.61 meters apart within rows. Growth metrics and stages were recorded and compared among treatments. Watermelon fruits were harvested at maturity over a one-week period and yield was compared. The final biomass was measured after harvest. Statistical analysis is ongoing, and a second year of this field trial will be completed in August 2024, allowing for final conclusions to be drawn.

Artichoke (Cynara cardunculus var. scolymus) belongs to the sunflower family and is cultivated for its flower buds. Being adapted to Mediterranean climates, artichoke plants require adequate winter chilling for flower bud induction and yet is susceptible to freeze damage. Because of these climatic requirements, nearly 100% of artichoke production in the United States currently comes from California. Insufficient winter chilling is among the major environmental constraints for artichoke production in subtropical and tropical climates. We started this study in 2015 with the goal of developing artichoke as a new winter crop in Florida. First, we developed a protocol for artificial flower bud induction using a plant hormone, gibberellic acid (GA3). With the optimum rate and timing, GA3 application is highly effective in inducing bud formation, irrespective of winter chilling. Second, we evaluated eight cultivars based on earliness of bud formation, yield, and bud quality. ‘Imperial Star’ and ‘Green Queen’ were selected as the most promising cultivars in Florida, with the maximum yields of 17.3 and 11.8 t ha–1, respectively. The current artichoke production guide provides recommendations on GA3 application, cultivars, planting configurations, plastic mulch, and basic pest management. In 2023, artichoke was grown on about 12 hectares in Florida using the production guide we developed. We are currently testing additional hybrid cultivars and assessing nutritional values and postharvest quality to enhance the viability of artichoke as Florida’s new winter crop.

The globe artichoke (Cynara cardunculus) is a large thistle crop of the Asteraceae family, native to the Mediterranean. Globe artichokes are a large, leafy plant, with edible component as an immature flower bud. With production dominated by California, Florida can provide a new commodity for southeastern growers while reducing our carbon footprint. Globe artichokes have not been a traditional crop in the state of Florida, even as a garden variety. This study demonstrates the need to focus on varieties for the subtropics. We evaluated the best performing artichoke variety in addition to the retail favorite by curb appeal. Within a farmer's market survey, more than 80% of shoppers voted for 'Green Queen' amongst five other varieties (Imperial Star, Green Globe Improved, etc.). It also represented the highest yielding, at 12,707 lbs/acre, followed by 'Imperial Star' at 11,484 lbs/acre. An artichoke was valued at $4 each globe, while the flower was $5 per stem during the Mother's Day market. The demand continues from chefs and newly transplanted retail shoppers.

Evaluating Faba Bean (Vicia faba) Performance Using Desalinated Irrigation Water and Compost Amendments in the Southwest - Jannatul Afroze
Planning for Success: A Roadmap to Establishing a Certified Naturally Grown Production Plot - Shelby Mendoza
Fertility Management in Soilless Growth Media for Beet Crop Production. - Bryce Waugh
Adaptation of AgRobotics for Onion Production in High Organic Matter Soils - Mary Ruth McDonald
Dual-cropping Sweetpotato for Greens and Root Production - Laura Schulz
Effect Of Selenium Fertilization on Beta-carotene Accumulation in Hydroponically Grown Two cress Varieties - Adekunle Adeyeye
Effect Of Levels Of Magnesium Fertilization On The Carotenoid Accumulation Among Three Kale Cultivars Grown Hydroponically. - Alex Kofi
Red And Blue LED Lighting Effects On Hydroponically Grown 'Koba' Green Onion - Kent D. Kobayashi
Plant Health Aerial Mapping Integration In Precision Agriculture Systems - Wael Elwakil
Evaluation of Vegetable Soybean Adaptations to South Florida's Tropical Climate- Xiaoying Li
Lettuce Cultivar Trials in a Deep-Water Culture (DWC) Hydroponic System - Alireza Rahemi

Water and soil salinity pose a significant challenge to global food production, particularly in semi-arid and arid regions. In many of these areas, the only available irrigation water often has high salinity levels. Utilizing irrigation water with high salinity can lead to salt accumulation in the rhizosphere, causing reduced infiltration rates, yield losses, decreased crop quality, and even potential plant mortality. Two strategies to address water and soil salinity include integrating compost soil amendments and implementing water desalination techniques. In addition to these two strategies, legumes are suitable crops for enhancing bioproductivity and reclaiming marginal lands due to their symbiotic association with rhizobia bacteria that can increase soil nitrogen. The objective of this study was to evaluate how the combined use of saline and desalinated water for irrigation, along with compost amendments, impacts faba bean germination, growth, physiology, and nodulation. Two common faba bean cultivars, Broad Windsor and Aquadulce were planted in fall of 2023 in field plots at the arid Brackish Groundwater National Desalination Facility, Alamogordo, NM, USA. Faba bean cultivars were grown in a combination of treatments of mulched composted wood with soil, bare soil, saline (1.97 dS/m) irrigation water, and desalinated (0.80 dS/m) irrigation water. Germination rates, plant nutrient composition, chlorophyll index, nodulation weight and number, along with root weight were measured. Preliminary results show that compost treatment as a main effect had a significant effect on faba bean germination rates with a 22-26% reduction in germination at 18, 25, and 35 days after planting (DAP) in plots with compost. By 107 days after planting, faba bean plants in the compost-treated plots showed no signs of nodulation, whereas the majority of plots without compost had nodules present. Water treatment significantly influenced the chlorophyll index of faba beans at 107 DAP; plants irrigated with saline water exhibited higher chlorophyll indexes. Compost treatments could have influenced germination rates due to variations in soil temperature, while nodulation might have been affected by adequate nitrogen potentially supplied by the compost. Upon completion of the current season and subsequent second season, we will have a more comprehensive basis to evaluate the relationships between compost application, saline irrigation water treatments, and their impacts on faba bean growth.

In the face of escalating environmental concerns, the horticultural sector is encouraged to pivot towards more sustainable and environmentally friendly production practices. Specifically, Certified Naturally Grown (CNG) emerged in 2002 as a new production system for small-scale producers rooted in organic farming principles and relying on peer-reviewed certification that fosters a community network. However, there is limited literature on the process of achieving CNG certification. Hence, this research strives to provide a detailed roadmap of the different phases of setting up a demonstrational CNG production system at the Oklahoma State University Student Farm including strategic planning and execution phases. The research plot is intended to serve as both an educational tool and a practical guide for growers aiming to transition to CNG practices. The implementation of this project began with familiarizing ourselves with the CNG organization, their inspection processes and planning accordingly. This is crucial to ensure the plot meets CNG criteria, focusing on sustainable practices and ecological balance from the outset. Next, the planning phase encompassed establishing the research plot including site selection, soil analysis, anticipated barriers of CNG certification, plot design and layout, resource assessment, and an implementation timeline. The planning phase aids in physically establishing the CNG demonstration plot and ensuring its role as a research and educational hub. By accurately addressing each planning component, the project aims to lay a solid foundation to demonstrate the viability of CNG practices in Oklahoma, stimulate community engagement, and promote a deeper understanding of sustainable agriculture practices. Ultimately, this project seeks to illustrate the detailed strategic planning and preparation required to develop a CNG production system. The education tools we develop will provide a template for producers aiming for CNG certification. With this initiative, we aim to educate growers on sustainable and resilient production methods and enable a transition towards them.

Greenhouse production is experiencing a rise, with more emphasis being placed on sustainability and efficient resource utilization. Accurate fertilizer applications are now more crucial than ever across various production systems. Soilless growth media possess different physical and chemical properties compared to soil, resulting in differences in nutrient retention capabilities. Because of this, it is imperative to apply precise fertilizer rates. This study evaluated 14 fertilizer blends with varying nitrogen (0-120ppm), phosphorus (0-120ppm), and potassium rates (0-120ppm). ‘Red Ace’ beet seeds were planted into 1-pint pots with Berger BM6 and plants were hand watered weekly with each treatment fertilizer rate to a 10% leaching fraction. Dry shoot weight, fresh root weight, dry root weight, number of leaves, and SPAD were taken as end measurements. This study found that high rate of nitrogen increased fresh shoot weight, while higher rates of potassium increased root weight. More studies should be done to dial in fertilizer rates for different specialty crops grown soilless greenhouse media.

The high organic matter soil (50 -80%) in the Holland Marsh, Ontario, Canada, is ideal for growing root and bulb vegetables but weeds also thrive. There are few registered herbicides and increasing herbicide resistance necessitates hand-weeding, but labor shortages and increased costs increase the interest in alternative methods. The solar-powered FarmDroid FD20 is one option, if adapted to work in vegetables. The FarmDroid was used to seed and weed onions on 2.8 ha of a commercial farm with weed control issues. The robot seeded 21 beds ~800 m long, with 4 single rows in each bed, and seeds 3.4 cm apart within the row, at 225 meters per hour. Seeding took 81 hours. Weeding was done with using a cultivator with metal tines to remove weeds growing between the rows it had seeded, at a speed of 500 m/hr. Weed counts were consistently higher in the robot-weeded than conventional-farmed sections (408 and 186 weeds/m, respectively), largely because of the inability of the robot to weed within the rows. There were no differences in yield. Small scale trials were conducted to compare conventional seeding of four double rows, with single rows as above and clusters of 3 seeds, 12 cm apart in the row. Emergence was 25, 35 and 17 plants/m for single, double and triple cluster seeding, respectively. There were no differences in yield at harvest (73-76 t/ha) but there were significantly more jumbo onions (42%) in those seeded in clusters, compared to the others (9 and 1%). A separate trial assessed seeding accuracy with increased speed. Emergence was highest for onions seeded at 200 m/hr with a significant decrease at speeds of 300 – 500 m/hr. Seeding in clusters shows promise for faster seeding and larger onions. Modifications to improve the configuration of tines for weeding are ongoing.

Sweetpotato (Ipomoea batatas) is a nutritious crop that produces edible roots, stems, and leaves. The tender vine tips, including both leaves and stems, are consumed as a vegetable in many regions of the world, including the Pacific Islands, Asia, and parts of Africa. A field experiment in Mount Vernon, WA evaluated time of vine tip (15 cm from the end of every vine) harvest on sweetpotato root yield of breeding lines USDA-04-284 (semi-erect growth habit), USDA-04-136 and USDA-04-791 (both with spreading growth habit). Treatments included no harvest during the season (control treatment, 1 harvest at time of root harvest), early harvest (8–12 weeks after transplanting, 4 harvests), late harvest (12–14 weeks after transplanting, 3 harvests), and continuous harvest (8–14 weeks after transplanting, 5 harvests). Vine tips were harvested at 2-week intervals during the harvest period, with an additional harvest for all treatments (including control) immediately before root harvest. Breeding line USDA-04-284 (semi-erect growth habit) produced 330 g of greens (fresh weight) per plant on average for all harvest treatments, which was significantly higher (p<0.0001) than USDA-04-136 and USDA-04-791 (spreading growth habit), which produced 118 and 139 g, respectively. Total greens production was significantly higher for the early and continuous harvest treatments (ca. 219 g/plant) than for the late and control treatments (ca. 173 g/plant) (p<0.01). Marketable root yield was similar for all the greens harvest treatments and was significantly lower for all harvest treatments compared to the control (p<0.0001). Compared to the control treatment, marketable root yield was lowest for early harvest and continuous harvest (ca. 34%), and highest for late harvest (51%). Across all greens harvest treatments, marketable root yield was lower compared to the control in the spreading breeding lines (33% and 40% for USDA-04-791 and USDA-04-136, respectively) than in the semi-erect breeding line (51% for USDA-04-284). While sweetpotato can be dual cropped for both greens and roots, the production of greens as an additional vegetable crop must offset financial losses of decreased root yield. Harvesting sweetpotato greens later in the season or only immediately before root harvest can reduce root yield losses while still producing a substantial crop of greens. Erect cultivars are best suited for greens production due to the lesser impact of greens harvest on root yield and higher production of greens.

EFFECT OF SELENIUM FERTILIZATION ON BETA-CAROTENE ACCUMULATION IN HYDROPONICALLY GROWN TWO CRESS VARIETIES. A.O. Adeyeye*; T. Nzaramyimana, Ph.D.; A. Kofi. College of Agriculture, Community, and the Sciences, Kentucky State University, Frankfort, KY 40601. Advanced plant cultivation techniques such as hydroponic vegetable planting, coupled with targeted soil micronutrient fertilization, exemplify sustainable agriculture's innovative approach to maximizing crop yields, enhancing nutritional quality, and minimizing environmental impact. This study will investigate the effect of selenium fertilization on the accumulation of beta-carotene in two varieties of hydroponically grown watercress. Hydroponic cultivation offers a controlled environment for plant growth, allowing precise manipulation of nutrient levels to optimize desired outcomes. Selenium, an essential micronutrient for both plants and animals, has been shown to influence the synthesis of secondary metabolites in plants, including carotenoids such as beta-carotene, which are important antioxidants and precursors of vitamin A. In this innovative idea, the experiment will be conducted using two cress varieties, (watercress) and (Upland cress), subjected to different levels of selenium fertilization. Selenium treatments will be applied according to a randomized experimental design, with each variety divided into multiple treatment groups receiving varying concentrations of selenium fertilizer. The hydroponic system provided consistent environmental conditions, including nutrient solution composition, pH, temperature, and light intensity, throughout the experiment. The beta-carotene content in watercress leaves will be quantified using High-performance Liquid chromatography (HPLC)analysis which is a technique used in analytical chemistry to separate, identify, and quantify components in mixtures and this allows for accurate measurement of carotenoid levels. Statistical analysis of the data will reveal significant differences in beta-carotene accumulation between selenium-treated and control groups within each watercress variety. Moreover, variations in beta-carotene accumulation will be observed between the two watercress varieties in response to selenium fertilization, indicating potential genotype-specific responses. Overall, the results will demonstrate that selenium fertilization influences beta-carotene accumulation in hydroponically grown watercress, with implications for agricultural practices and human nutrition. Understanding the interactions between selenium supplementation and carotenoid synthesis in watercress can inform strategies to enhance the nutritional quality of crops and promote sustainable agricultural production systems. Keywords; Selenium fertilization, Beta-carotene, Hydroponic, Watercress varieties, Agricultural sustainability, Crop yields, Environmental impact, Spectrophotometric analysis,

Phytonutrients in fruits and vegetables are crucial in promoting human health and preventing various diseases. Among these are carotenoids that are found abundantly in green leafy vegetables like kale, which have garnered significant attention due to their numerous health benefits, including antioxidant and anti-inflammatory properties. Despite kale’s reputation as a nutritional powerhouse, little research has focused on the effect of magnesium fertilization on carotenoid production and accumulation in this vegetable. This study aims to address this gap by investigating the impact of different rates of magnesium fertilization on the carotenoid contents and elemental nutrient levels of three hydroponically grown kale cultivars. The Darkibor, Mamba, and Red Russian kales would be grown hydroponically using Hoagland solution in a greenhouse. Different magnesium rates at 0 mgL-1, 12.3 mgL-1, 24.6 mgL-1 and 59.2 mgL-1 would be used. Carotenoid contents and levels in the three kale varieties will be analyzed using High-performance Liquid Chromatography. Additionally, an Agilent 7500ce inductively coupled plasma-mass spectroscopy (ICP-MS) system will be used to measure their elementary nutrient levels. Data would be analyzed using the PROC GLM analysis of variance (ANOVA) and regression analysis procedure of the SAS v9.1 software package. At the end of the experiment, it is expected that increased rates of magnesium fertilization will lead to a significant increase in the accumulation of carotenoid and elemental nutrient levels in each kale cultivar. Understanding how magnesium fertilization influences carotenoid accumulation and other nutrient levels in kale could improve nutritional quality, thereby reducing reliance on dietary supplements to address nutrient deficiencies. Keywords: Phytonutrients, Magnesium, Carotenoids, Kale, Antioxidants

Food safety, environmental impact, and efficient energy usage are growing concerns in horticultural production systems. In Hawaii, 'Koba' and local strains of green onion can be planted year round. The use of artificial lighting in green onion production could be a solution to help address the above concerns. The objective of this study was to compare the effects of red and blue LED lighting on the growth of 'Koba' green onion plants in a noncirculating hydroponic system. 'Koba' green onion (Allium fistulosum) seeds were germinated in Oasis® cubes under T5 high output fluorescent lighting in the lab. Seedlings were then transferred to 5.1-cm net pots, which were placed in 1.9-liter containers containing a hydroponic nutrient solution of Hydro-Gardens' Chem-Gro lettuce formula 8-15-36 hydroponic fertilizer with added calcium nitrate (19% Ca and 15.5% N) and magnesium sulfate (9.8% Mg and 12.9% SO4). Half of the seedlings were grown under red LED lighting (82 µmol/m2/s, 12-h photoperiod) and half under blue LED lighting (82 µmol/m2/s, 12-h photoperiod). Data was collected at the end of the experiment. At the end of the study, there were significant differences in plant height, number of leaves per plant, stem diameter, total leaf length per plant, leaf dry weight per plant, and root dry weight per plant. For all these variables, red LED lighting resulted in greater values than those for blue LED lighting. In conclusion, different LED lighting could be used to supply artificial lighting for 'Koba' green onion plants. Red LED lighting enhanced the growth of 'Koba' green onions.

Aerial multispectral imaging is a great tool for early detection of plant health stresses. There is a variety of sensing hardware with even more options for data analysis ranging in their ease of use and computing power requirements. These tools have been used very successfully in research settings such as breeding trials, nutrient management evaluations, and pesticide efficacy trials. These technologies have tremendous potential benefits if utilized in commercial production systems. While some agronomic crop producers have been using some of these technologies to some extent, there have been various barriers to adoption in specialty crop production. Data collection, analysis, and computing power limitations are some of the primary challenges. However, we find that there is a serious limitation in integration and data output compatibilities from the analysis side to plugging in precision ag equipment. In this project, we examine multiple systems and platforms from data collections to creating decision maps used in field equipment. This project is conducted in partnership with specialty crop growers and aerial service providers. We are in the process of streamlining the process of data collection, analysis, and creation of decision maps, to optimize the use of ground based or aerial fertility and pesticide precision applicators.

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

Lettuce (Lactuca sativa L.) is a leafy vegetable in the Asteraceae family and is classified into various types, such as Romaine, Butterhead, Crisphead (Iceberg and Batavian), Latin, Leaf, and Stem. Lettuce propagates by the seeds. The seedling can grow in soil or a hydroponic system in a controlled environment Agriculture (CEA) system. This study was conducted to study the ability of different types of lettuces to grow in a hydroponic system and to assess the effect of light, humidity, and temperature on the yield. The experiment was conducted twice (2023 and 2024) in the Department of Agricultural Science lab at Morehead State University. Four lettuce cultivars, including 'Gustav's Salad' and 'May Queen' as the Butterhead type, 'Ice Queen' as a Crisphead type, and 'Lollo' as the Leaf type, were planted directly on rock wools (Rockwool Starter Plugs) in 2-inch Garden Net Pot in hydroponic containers. The commercial aquarium pumps constantly aerated the nutrient solution. Plants were fertilized with liquid plant food, and the Standard Hydroponic solution controlled the pH. The artificial light was provided by a mix of different lights (µmol/m2/s), including LEC, LED, and Fluorescent, for 16 hours daily under different temperatures (°C) and humidity (%). Biological control products were used for pest and disease control. Harvesting was done after 60 days, and fresh and dried yields of leaves were calculated. The roots were also collected and weighed. Dried leaves and roots were ground and analyzed. The primary results show significant differences among different cultivars.

Evaluation of Wireworm Resistant Sweetpotato Cultivars in Western Washington - Laura Schulz
Variation in Toxic Element Presence in Sweetpotato Storage Roots From A Small Plot Trial: Sampling Implications - Arthur Villordon
Striving to stay clean: Production of sweetpotato nuclear stock used for certified seed growers in North Carolina - Christie Almeyda
Effects on yield, quality, sugar content and soil health indicators of foliar and soil applied Chlorella vulgaris in ‘Beauregard’ sweetpotato (Ipomoea batatas [L.] Lam). - Brian Ward
The Effect of Potassium Fertilization on Potato Tuber Nutrition in the Columbia Basin of Oregon - ruijun qin
Predicting Potato Tuber Yield Through Hyperspectral Signals and Machine Learning - Ravinder Singh
Evaluating King Stropharia Mushroom as an Intercrop in Asparagus and Tomato Production - Olalekan Sipasi

Sweetpotato (Ipomoea batatas) is a nutritious, productive, and resilient crop that is grown worldwide and is gaining popularity throughout the U.S. In western Washington, wireworms (Agriotes lineatus, A. obscurus, and Limonius canus) are the primary pest impacting sweetpotato production. Wireworm resistant cultivars can provide an effective and sustainable pest management tool for growers. A field experiment in Mount Vernon, WA included nine sweetpotato cultivars and breeding lines: wireworm-susceptible cultivars Bayou Belle, Beauregard, Covington, and Orleans; wireworm-resistant cultivars Cascade and Monaco; and wireworm-resistant breeding lines USDA-04-136, USDA-04-284, and USDA-04-791. Storage roots were graded according to USDA sweetpotato categories and root weight, number, and wireworm damage [Wireworm-Diabrotica-Systena (WDS) severity index] were measured. Marketable yield ranged from 22 t/ha (USDA-04-136) to 57 t/ha (‘Bayou Belle’) (p

The overarching goal of FDA’s Closer to Zero (C2Z) action plan is to reduce dietary exposure to contaminants, in foods commonly eaten by babies and young children, to as low as possible while maintaining access to nutritious foods. In addition to establishing action levels for specific toxic elements (TEs), C2Z proposes to develop new and improved testing methods to measure lower levels of contaminants in food and monitor levels over time to determine potential adjustments to proposed action levels. These proposed testing and monitoring activities represent potential added costs to the producer. The sweetpotato (Ipomoea batatas L.) is a leading baby food raw product but very little information is available on the appropriate frameworks for optimal sampling procedures to ensure accuracy and precision of surveys, especially at the field scale. A field trial to investigate the role of commonly used soil amendments in reducing storage root accumulation of arsenic (As), cadmium (Cd), and lead (Pb) revealed interesting trends that merits further investigation. Three random U.S. No.1-sized storage roots were sampled from each of three random plants from each of two unamended (control) plots (plot size=12’ x 3.3’) and analyzed for TE presence at a commercial laboratory. The Pb and Cd content of storage roots from cultivars ‘Bayou Belle’ (BB) (SDs: Cd=1.1, Pb=1.3) and ‘Beauregard’ (BX) (SDs; Cd=1.8 Pb=1.3, Cd=) showed more variability relative to As (SDs: BB=0.5, BX=0.6). There were no differences between two cultivars for all TEs measured. A possible follow-up study could investigate plant- or soil-based variables that contribute to variation in Pb and Cd accumulation. Such findings can be used to improve the accuracy and precision of sampling approaches to enable producers to meet C2Z goals, especially as it concerns sampling of storage roots for monitoring and enforcement purposes.

The Micropropagation and Repository Unit (MPRU) produces, maintains and distributes meristemmed-tip culture, virus-tested, indexed, true-to-type sweetpotato nuclear plants to certified seed growers in NC. Under the certification program, seed growers use nuclear plants for production of G0 plants in greenhouses, and subsequently G1 and G2 plants and storage roots (seed) in the field. All these materials are inspected and certified by NC Crop Improvement Association, Inc. (NCCIA). The MPRU is a clean center for sweetpotato under the National Clean Plant Network (NCPN) umbrella. It works closely with the NC State sweetpotato breeding and genetics program to clean advanced selections yearly. The MPRU distributes about 90,000 nuclear plants to NC certified seed growers every year. It is estimated that about 70% of the commercial sweetpotato acreage in NC is planted annually with stocks derived from the MPRU. It is known that the accumulation and perpetuation of viruses in sweetpotato is a major constraint for production of seed and the commercial crop. The aphid-transmitted potyvirus complex is prevalent in NC and comprises Sweet potato feathery mottle virus (SPFMV), Sweet potato virus G (SPVG), Sweet potato virus C (SPVC) and Sweet potato virus 2 (SPV2). In order to evaluate the performance and quality of clean seed after it had been integrated into commercial sweetpotato operations, NCPN field trials were carried out in 2021 and 2023 with Covington and Beauregard as evaluated varieties. Because sweetpotato is vegetatively propagated, viruses and mutations can accumulate readily which can lead to cultivar decline. G1 seed was used as a reference to compare the yield and virus incidence of growers’ generation 2 (G2), generation 3 (G3) and generation 4 (G4) seed roots (grown in the growers’ seed production fields 1, 2 or 3 years following the year of clean seed production). Virus detection data suggested a low incidence of viruses (mainly SPFMV) on G1 material. Potyviruses (mainly SPVG, SPVC and SPFMV) started to be prevalent on G2 and G3 material. In the older generation evaluated (G4), all potyviruses (SPVG, SPVC, SPFMV and SPV2) were detected. In general, the prevalence of four potyviruses was associated to higher seed generations, indicating a buildup over the years on clean seed regardless of the variety. Yield data suggested a negative impact due to virus infections in Beauregard. This study will allow us to understand the impact of clean seed on the economic value of the crop to educate growers and stakeholders.

Commercial sweet potato production has seen a recent surge in both fresh market and processing acreage in South Carolina. Producing quality conventionally and organically grown sweetpotatoes is a challenge in South Carolina due to numerous biotic and abiotic factors. One of the most important deciding factors on sweetpotato yield is germplasm and fertility. In this study we examined effects on yield and quality of foliar and soil applied Chlorella vulgaris (CV) in ‘Beauregard’ sweetpotato (Ipomoea batatas [L.] Lam). Chlorella vulgaris (EnSoil Algae, Enlightened Soil Corp) is marketed under the USDA/APHIS category of soil amendments and Plant Growth Enhancers (PGE). This study was conducted in 2022-2023 in a randomized complete block full factorial design with 4 replications and a total of 17 treatments with a product rate of 250ml/Ac, including the following: 1) Unfertilized Control, 2) 100 % Preplant Granular Fert. (PGF), 3) Soil Algae Application (SAA), 4) Foliar Algae Application (FAA), 5) 100% PGF SAA, 5) 100% PGF SAA, 6) 100% PGF FAA, 7) 100% PGF SAA FAA, 8) SAA FAA, 9) 25% PGF SAA 75% Drip Irrigation Fert.(DIF), 10) 25% PGF FAA 75% DIF, 11) 25% PGF SAA FAA 75% DIF, 12) 25% PGF SAA, 13) 25% PGF FAA, 14) 25% PGF SAA FAA, 15) 25% PGF 75% DIF, 16) 75% DIF, 17) 25% PGF. Results were mixed over time with 2022 being a better growing year. In 2022, USDA grade Jumbo roots were 10% numerically greater in SAA treated plots, than 25% PGF SAA 75% Drip Irrigation Fert. (DIF) and 9% over SAA and FAA. In 2023 there were similar trends, with USDA grade Number

Potato (Solanum tuberosum L.) crops require a high amount of potassium (K) to achieve the ideal yield and quality. However, the effect of K fertilization on potato tuber nutritional value is largely unknown. Based on the tubers from two-year field trials on a Quincy loamy fine sand soil in the Columbia Basin of Oregon, we evaluated yield, specific gravity, nutritional contents (i.e., ascorbic acid, tyrosine, chlorogenic acid, tryptophan, phenylalanine), and nutrient contents (nitrogen [N], phosphorus [P], K, and sulfur [S]) of three potato varieties (Clearwater Russet, Russet Burbank, and Umatilla Russet) under three K rates (0, 448, and 897 kg ha-1). Our results showed that the K application increased the yield of >170 g tubers but had no considerable effect on the total tuber yield. The application of K tended to decrease specific gravity regardless of varieties and years. Russet Burbank had the lowest specific gravity while Clearwater Russet had the highest one. Most of the nutritional contents were higher in 2020 than in 2021. Russet Burbank generally had the highest nutritional contents except for ascorbic acid compared to two other varieties. The application of K generally did not affect tuber nutritional contents but reduced the amounts of tyrosine in Clearwater Russet and Umatilla Russet in 2020. Fertilization of K resulted in an enhanced K content in the tuber, with the highest K application rate exhibiting a 35% increase in K compared to the control. However, it did not have any discernible effects on N, P, and S contents in the tubers. The tuber P and S were lower in Russet Burbank than other varieties. In general, there is no strong relationship between K fertilization and tuber nutritional contents.

Potato production is crucial for global food security, and with an increasing demand for food and a diminishing supply of fertile land, there is a need to boost production. Remote sensing technologies, such as high-resolution hyperspectral sensors, have the potential to provide valuable insights into potato growth, yield, and quality. Narrow spectral bands captured by these sensors are directly linked to biophysical parameters and can accurately estimate crop parameters. Recent studies have utilized hyper-spectral imagery acquired from proximal sensor such as ASD FieldSpec to estimate various crop parameters and yield. The results from these studies are promising, indicating that hyper-spectral sensors have the potential to improve crop management and agricultural practices. Moreover, the integration of remote sensing data with advanced analytical techniques, such as machine learning, helps in accurately estimating yield and yield components. In this study we are testing two machine learning such as PLSR and RF to predict biomass and N uptake in-season. Results from this indicate that PLSR performs better in predicting biomass and N uptake in potatoes. Moreover, yield can be best estimated at tuber bulking stage.

Stropharia rugosoannulata (L.), the King Stropharia or Wine Cap mushroom, is a wood-loving fungus that grows well on organic mulches. Some vegetables can be successfully grown using organic mulches like woodchips or straw. As a result, farmers may be able to enhance their income by intercropping Stropharia mushrooms with their vegetable crops. However, no study has been identified that assesses this strategy's potential or effect on vegetable yields. Thus, a Stropharia-asparagus intercrop was evaluated by applying woodchips at three depths (4, 8, and 12 in), and a Stropharia-tomato intercrop was evaluated using woodchips, wheat straw, and soy straw (all at 6 in depth). Both experiments utilized a randomized complete block design (RCBD) with four replications and included bareground controls. The tomato study also included a positive mulch control using black plastic. In the fall of 2021, black plastic, inoculated wheat straw, and uninoculated soy straw and woodchip mulch provided earlier harvest than unmulched plots, while the soy treatments and bareground and black plastic controls increased total fruit numbers. In 2022, overall tomato production decreased, resulting in no marketable fruit. Across both 2022 and 2023 asparagus harvest began earlier with decreasing depths of mulch, and therefore lasted longer. Inoculated plots also produced more marketable spears than uninoculated plots. And, 12 in woodchip mulch significantly inhibited asparagus emergence and is therefore not recommended. These results suggest that a Stropharia-tomato intercrop may not be feasible without additional work, though a Stropharia-asparagus intercrop shows great promise. In fact, in 2023, mushrooms were observed in uninoculated plots demonstrating the gregarious growth of Stropharia in woodchip mulch on asparagus plots. The relative success in asparagus plots supports a need for further research to evaluate other Stropharia-vegetable [or fruit] intercrop candidates and/or strategies to improve compatibility.