Location: Plant Genetic Resources Conservation Unit
2025 Annual Report
Objectives
Objective 1. Optimize and implement best management practices to conserve, maintain, and distribute plant genetic resources and associated descriptive information.
Sub-objective 1.A. Optimize and implement best management practices based on the NPGS plan to conserve and maintain more than 100,000 accessions of priority plant genetic resources and their associated information.
Sub-objective 1.B. Distribute plant genetic resources and associated information to stakeholders, scientists, plant breeders, and educators.
Objective 2. Ensure accessibility, quality, and integrity of plant genetic resources through regeneration and conservation practices.
Sub-objective 2.A. Monitor and assess plant genetic resources for viability, trueness to type, vigor, and overall health.
Sub-objective 2.B. Conduct field and greenhouse regenerations of priority crops and their wild relatives based on low viability and low seed numbers to replenish and safeguard high quality plant genetic resources.
Objective 3. Conduct research to characterize and evaluate plant genetic resources for priority genetic, agronomic, nutritional, and health related traits.
Sub-objective 3.A. Characterize plant genetic resources using basic descriptors and other phenotypic data to describe useful agronomic and horticultural traits.
Sub-objective 3.B. Evaluate plant genetic resources using physiological, biochemical, and genetic techniques to determine seed quality, tolerances to biotic and abiotic stresses, and variations in nutritional and health related traits.
Approach
This project is part of a comprehensive nationwide program, the National Plant Germplasm System (NPGS), that conserves plant genetic resources for present and future crop improvement and related research activities. The project acquires, conserves, documents, distributes, characterizes, and evaluates the genetic resources of agronomic and horticultural crops including sorghum, peanut, peppers, watermelon, squash, eggplant, okra, sweetpotato, subtropical and tropical legumes, warm-season grasses, cowpeas, annual clovers, various industrial crops, other crops, and their wild relatives. All objectives and sub-objectives are non-hypothesis driven research as the mission is predominantly service oriented providing plant genetic resources and associated information to plant breeders and researchers for use in their scientific efforts. This project focuses on providing high quality, well-documented plant genetic resources and associated information to ARS, university, industry, and other research and education programs worldwide. The project investigators work closely with domestic and international scientists in helping them obtain the appropriate germplasm and information to achieve their research goals. Scientists remain current in all areas of research and education on each specific crop and their wild relatives through involvement with crop-specific Crop Germplasm Committees (CGC) and direct contact with scientists and educators who request plant genetic resources and information.
Progress Report
A large and highly valuable set of plant germplasm of sorghum, millets, peanuts, sweet potatoes, grasses, cowpea, vegetables, industrial crops, medicinal crops, and other crops were preserved and distributed to scientists and plant breeders. ARS researchers at Griffen, Georgia believe this germplasm provides the buildings blocks crucial to the development of new varieties to increase farmers’ yields, crop nutritional value, and protect U.S. agriculture. A total of 105,957 accessions of 1,575 plant species representing 263 genera were maintained in the Griffin, Georgia's plant genetic resources collection. Over 88% of these accessions were available for distribution to users and over 95% were backed up securely at a second location (Subobjective 1A). A total of 33,260 seed and clonal accessions were distributed upon request to scientists and educators worldwide in CY2024. Sorghum, pepper, peanut and guar were the most distributed crops. So far, this fiscal year 27,155 accessions have been distributed with sorghum and okra being the most distributed crops (Subobjective 1B). Clonal collections were continually maintained and distributed to stakeholders. Clonal collections include warm-season grasses, bamboo, Chinese water chestnut, perennial peanut, and sweet potato. Preservation methods include tissue culture, field plots, greenhouse plants, and hydroponics. Germination testing continued for newly regenerated germplasm but only a limited basis due to the vacancy in a critical scientific support position (Subobjective 2A). Regeneration and evaluation activities are listed in detail below. These activities ensure that the crop genetic resources at the Griffin location are safeguarded for future use to develop new cultivars and identify novel traits and uses in our food and fiber crops ultimately increasing farmer productivity and national food security.
Regenerations (Subobjective 2B):
• Successful seed regenerations and descriptor characterizations were completed late 2024 for 84 accessions of 28 castor beans, 25 legumes, and 31 grass accessions.
• Regenerations continue for 175 accessions of 44 industrial crops, 79 legume, and 52 grass accessions in field plots, nursery pots, and hydroponic systems (utilized for seed and plant rescue).
• Between 60 and 80 seeds each of 500 different peanut accessions were planted in field plots in Byron, GA, to harvest fresh seeds to replenish seed inventories.
• Plants of 137 different peanut wild relatives are being grown in the greenhouses to harvest fresh seeds to replenish seed inventories.
• 100 different accessions each of cowpea and mung bean (total of 200 accessions) were planted in field plots in Griffin, GA, to harvest fresh seeds to replenish seed inventories.
• Fresh pods harvested from 60 different accessions of 31 peanut wild relatives were submitted to the seed storage for replenishment of seed inventories.
• Fresh seeds harvested from 133 cowpea and 103 mung bean accessions were submitted to the seed storage unit for replenishment of seed inventories.
• Regenerations of cultivated and wild relatives of pepper, eggplant, and watermelon are being conducted in the greenhouse and fields in Byron and Griffin.
• Sorghum regenerations are being conducted in collaboration with ARS researchers in Puerto Rico.
Characterizations (Subobjective 3A and 3B):
• Research continues to identify ornamental characteristics, specifically leaf color, from a field grown selected roselle sample. This selection will ultimately be used by the ornamental nursery industry as well as farmers, growers, and in home gardens. It will add economic value for farmers.
• Research continues to identify roselle samples which will yield quality calyces and seed under field production systems in collaboration with researchers in Lithonia, GA. This research will result in the identification of day neutral roselle samples with high quality plant, calyx, and seed production characteristics useful for edible food products such as jams, chutney, and tea. New and healthy food products are very popular and important in the U.S. markets.
• Research continues to verify field seed production from cold tolerant, over-wintered roselle samples with ornamental calyces. This evaluation will determine high quality roselle seed production and tolerance to over-wintering and freezing temperatures. This work will help the ornamental plant industry as well as farmers of ornamental plants with high quality seed and calyx production. Over wintering and cold tolerant roselle samples would add value to the perennial plant markets.
• Research has begun to evaluate 34 roselle accessions in collaboration with a University of Georgia Controlled Environment Breeder at Griffin, Georgia for the identification of day neutral samples. Selected samples will continue in a breeding cycle for the development of high-quality calyx production which will be used by small farming operations. This research will add value to controlled environment farming systems.
• Digital images of pods and seeds of 48 different accessions of peanut wild relatives were uploaded to the public database Germplasm Resources Information Network-Global (GRIN- Global).
• Seed mineral content, especially Iron, Zinc and Phosphorous, in cowpea was measured to determine their role in plant growth and implications for child nutrition in fermented and non-fermented cowpea-based foods. This research was done in collaboration with the University of Nevada-Reno.
• DNA analysis of different peanut accessions is being carried out to identify unique accessions to efficiently maintain and manage the national peanut seed collection in Griffin, GA. This research is being done in collaboration with the researchers in Tifton, GA and Huntsville, AL.
• For developing new peanut germplasm lines (high oil content and disease resistance), we made four crosses and produced 30 true F1 hybrid seeds. These F1 seeds will be planted for developing F2 population to select high oil content and disease resistance (mainly leaf spot resistance) germplasm lines.
• A total of 2931 peanut and sesame samples were measured for oil content, 1006 samples for fatty acid composition, and 809 samples for protein content. The samples included the peanut Multi-parent Advanced Generation Inter-Cross (MAGIC) population, wild species, cultivated peanut, allotetraploids, drought tolerance varieties plus sesame germplasm accessions and mutant lines.
• Seed image scans with data extraction and genotyping of high priority subsets of the sorghum germplasm collection are being done in collaboration with ARS, Ithaca, NY.
Accomplishments
1. Increasing nutritional value of sesame. Sesame farmers and researchers are interested in traits with improved nutritional value such as oleic acid in sesame seed which contributes to longer shelf life and can lower heart disease. More than 1000 sesame seed samples in the USDA sesame collection in Griffin, Georgia were evaluated for seed oil content, fatty acid composition, and 100 seed weight. A high amount of variation was discovered among the sesame samples for these biochemicals. Two of the sesame samples resulted in higher oleic acid content than all other samples. These samples can be used by plant breeders for the development of improved varieties with traits favorable to farmers and consumers alike.
2. High oleic acid content significantly extends the viability of long-term stored peanut seeds. The viability of peanut seed in storage is very important for farmers and germplasm curators. After screening the entire USDA National Plant Germplasm System Peanut Collection in Griffin, Georgia, we identified a unique peanut inventory with uniform morphological characteristics but marked differences in seed fatty acid composition (high oleate >74% and normal oleate <58%). Through genotyping and chemical analysis in multiple field trials, we found that high oleate seeds had a significantly higher germination rate and normal seedling growth rate compared to normal oleate seeds. These results demonstrate that high oleic peanuts will store longer and germinate more consistently in farmer fields and remain viable longer in cold storage conditions such as those used in germplasm conservation.
Review Publications
Xu, Y., Wang, M.L., Devlet, A., Han, L., Tang, C., Tan, T., Xie, G. 2024. A comprehensive method to select energy sorghum hybrids for bioethanol production. Industrial Crops and Products. 191. https://doi.org/10.1016/j.biombioe.2024.107436.
Jha, U., Shafi, S., Tallury, S.P., Nayyar, H., Ciampitti, I., Siddique, K.H., Prasad, V.P. 2025. Differential physiological and yield responses of selected mung bean (Vigna radiata (L.) R. Wilczek) genotypes to various high-temperature stress regimes. Scientific Reports. 15:1034. https://doi.org/10.1038/s41598-024-84615-6.
Jha, U., Shafi, S., Tallury, S.P., Nayyar, H., Udgata, A., Ciampitti, I., Siddique, K.H., Prasad, V.P. 2025. Dynamic changes in seed nutritional components of mung bean [(Vigna radiata (L.) R. Wilczek)] under heat stress. Scientific Reports. 15:12586. https://doi.org/10.1038/s41598-025-93992-5.
Wang, M.L., Tonnis, B.D., Morris, J.B., Pinnow, D., Stigura, N.E., Benke, R.L., Li, X. 2025. Mining seed quality traits in the USDA sesame germplasm collection identifies useful accessions for improving nutritional breeding. Journal of the American Oil Chemists' Society. p. 1-9. https://doi.org/10.1002/aocs.12933.
Wang, M.L., Tonnis, B.D., Tishchenko, V., Tallury, S.P. 2025. High oleic acid significantly extends the viability of long-term stored peanut seeds. Plant Genetic Resources: Characterization and Utilization. 1-5. https://doi.org/10.1017/S1479262125000097.
Deraniyagala, A.S., Roy, A., Tallury, S.P., Sudhini, H.K., Culbreath, A., Bag, S. 2025. Development of a multiplex TaqMan assay for rapid detection of groundnut bud necrosis virus: a quarantine pathogen in the USA. Viruses. https://doi.org/10.3390/v17040532.