Resources

UGA’s Plant Genetic Resources Conservation Unit protects seeds for the future

Adam Gregory, an agricultural specialist from UGA’s College of Agricultural and Environmental Sciences, is the Farm Operations Manager for the Plant Gene Resources Conservation Unit. “Half the fun of the job is knowing how important this resource is to the germplasm system,” Gregory said. “A lot of these species are bred for disease resistance or some other little trait.”

The seeds of knowledge are planted every day at the University of Georgia. But the UGA Griffin campus sows seeds to store, helping with plant preservation and research on a global scale.

UGA-Griffin is home to the Plant Genetic Resources Conservation Unit (PGRCU), which is part of the United States Department of Agriculture’s largest national plant germplasm system, covering 19 sites across the United States, as well as three non-USDA affiliated collections.

Located in an unassuming one-story brown brick building near the center of campus, the PGRCU stores a large collection of germplasm for sorghum – the largest crop they hold – groundnuts, warm season grasses and various vegetable crops such as okra and eggplant.

Germplasm is living genetic material, such as seeds or tissues, that is conserved for plant breeding, preservation, and other research uses. “It’s the foundation of plant breeding and helps ensure genetic diversity,” said Melanie Harrison, USDA supervising agronomist for the PGRCU. “We need genetic diversity to develop and improve crop varieties to meet the needs of a growing population and a changing environment.”

The PGRCU is a joint effort between the USDA Agricultural Research Service (USDA-ARS) and the Southern State Agricultural Experiment Stations – the PGRCU holds a highly diverse collection of seeds, over 1,600 species different in everything, she explained.

“We have USDA-ARS employees and UGA employees who maintain the different populations and distribute them,” Harrison added. “The whole mission is to collect, maintain and preserve these unique plant populations that have been collected all over the world and distribute these populations for research purposes.”

Adam Gregory, an agricultural specialist from UGA’s College of Agricultural and Environmental Sciences, is the unit’s farm operations manager, overseeing field operations and building the farm team along with the research technician Luke Doss. UGA research technicians and support staff work directly with USDA curators to grow important crops in the field and harvest seeds for collection processing, storage and distribution. “They’re more involved with each individual culture,” Harrison explained.

Gregory worked as a research technician at various UGA facilities before joining the PGRCU. He and his team maintain the unit’s equipment, maintain the grounds around research plots, irrigate and fertilize crops, and harvest seeds and planting material when ready. Because the plants grown are for research and conservation, the system works much like an organic farm, Gregory said.

“We are very labor intensive. Because we don’t grow typical crops, we can’t spread herbicides and a lot has to be done by hand,” he said.

Seeds of different colors, shapes and sizes from multiple seed packets spill together
“We need genetic diversity to develop and improve crop varieties to meet the needs of a growing population and a changing environment,” said Melanie Harrison, research manager at PGRCU. (Photo by Melanie Harrison)

Seed drying on a metal rack at the PGRCU
UGA research technicians and support staff work directly with USDA curators to grow important crops in the field and harvest seeds for processing, storage, and collection distribution. (Photo by Melanie Harrison)

The Griffin site works with the USDA-ARS National Laboratory for Preservation of Genetic Resources, located in Fort Collins, Colorado. The national laboratory is part of the National Plant Germplasm System and serves as a backup site for other sites.

“A subset of each seed sample is sent to Fort Collins for safekeeping in the event of a fire or other disaster that could destroy them,” Harrison said.

During a typical season at the facility, UGA personnel work with USDA conservators and have primary responsibility for planting seed increments for each crop in the field, monitoring them throughout of the season for their health and viability and to ensure that they are free from disease. The team also harvests and cleans the new seeds before submitting them to a storage technician, who packs the seeds and puts them in the PGRCU’s freezers.

Refrigerated seed storage at PGRCU
The PGRCU stores a large collection of germplasm for sorghum – the largest crop they hold – groundnuts, grasses and various vegetable crops, 1,600 species in all. (Photo by Biological Science Lab Technician Tiffany Fields)

“Seeds last longer when stored in cold temperatures with low humidity rather than room temperature, so we store our seeds in cold rooms and freezers to increase their longevity. However, the seeds will lose viability over time,” Harrison said. “We have a germination technician who monitors seed viability and performs thousands of germination tests each year. This data is used by conservators to prioritize regenerations in the field. The goal is to reduce the number of times a particular seed sample will need to be regenerated while maintaining high viability in storage.

When restocking seeds for a crop, technicians plant the seeds in greenhouses and fields to produce fresh seeds. PGRCU staff are meticulous in maintaining the genetic purity of each type of germplasm.

“It depends on the harvest and the details,” Harrison said. “Many insect-pollinated crops, such as some vegetables, are grown under pollination cages to reduce cross-pollination between different plant populations. You don’t want an insect visiting one population and then another because then you might have cross-pollination. All populations are single populations.

The unit’s crops are grown on approximately 40 acres spread over plots on the Griffin Campus, the nearby Westbrook Research Farm, and research plots in Byron, Georgia, as well as six to eight greenhouses at different sizes on the Griffin campus.

“Half the fun of the job is knowing how important this resource is to the germplasm system,” Gregory said. “Many of these species are bred for their disease resistance or for other small traits. You may not see commercial value in it, but genetics can deliver something that is commercially viable.

It’s hard work but has a big payoff.

“We help protect seeds for future generations,” Harrison said. “It’s a team effort and it’s definitely worth it.”

Maria M. Lameiras is an editor at the College of Agricultural and Environmental Sciences at the University of Georgia.