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SPRING FARM: Research aims for heat-resistant soybeans |

Soybeans are one of the major cash crops grown in South Carolina, but high temperatures during the growing season limit yields and reduce profits.

Two Clemson University researchers believe that a better understanding of the traits associated with heat tolerance in soybeans can help develop heat-tolerant varieties that can lead to more sustainable agricultural production. They received a grant of $649,895 from the National Institute of Food and Agriculture of the United States Department of Agriculture (USDA-NIFA) to study the effectiveness of soybeans for tolerance to heat. This grant continues research in which researchers examine the characteristics that lead to heat tolerance in soybeans.

The researchers leading this study are Sruthi Narayanan, assistant professor and researcher in the Department of Plant and Environmental Sciences at Clemson, and Sachin Rustgi, assistant professor and researcher in molecular breeding housed at the Pee Dee Research and Education Center (REC) in Florence, North Carolina. South.

“The long-term goal of this project is to improve the climate resilience of soybeans so that they can produce stable yields under heat-stressed conditions,” said Narayanan, the project’s principal investigator.

Researchers are looking for soy genes associated with lipid metabolic changes that contribute to heat tolerance. Researchers plan to identify molecular markers to use in screening soybean plants for heat tolerance. Rustgi will use equipment from the Pee Dee REC Molecular Breeding Laboratory to conduct its research.

“Molecular markers for heat tolerance will be the main deliverable of this project,” Rustgi said. “These markers will help advance soybean breeding programs in developing heat-tolerant varieties.”

The project aims to generate information on lipid metabolic changes, physiological mechanisms and their genetic controls that confer heat tolerance in soybeans. During the project, researchers will evaluate contemporary high-value soybean varieties with high oleic acid content in the seeds and drought tolerance. The data generated will provide growers with information on the heat tolerance of these varieties.

Soybeans are typically planted in South Carolina from May 10 to July 11 and harvested from October 20 to December 30. They require a soil temperature of around 54 degrees to germinate. Ground temperatures are generally higher than air temperatures during the summer months. Climate data shows that the average air temperature from May to July in South Carolina is 89 degrees. According to the Environmental Protection Agency, temperatures in South Carolina have warmed by half a degree to a degree over the past century.

Soybeans are a major crop grown in South Carolina. According to the USDA’s National Agricultural Statistics Service, 310,000 acres of soybeans were harvested in the state in 2020. In addition to being an important crop for South Carolina farmers, soybeans are also an important source protein for many people around the world.

Michael Plumblee, corn and soybean specialist with the Clemson Cooperative Extension Service housed at Edisto REC in Blackville, said the project could be very beneficial to the state’s soybean industry.

“With our hot summer climate, we often see temperatures above 85 degrees during the growing season,” Plumblee said. “At temperatures above 85 degrees, we can experience several different issues with soybeans, such as reduced nodulation, slowed photosynthesis, flower and small pod abortion, and smaller seed production. All of these can limit performance.

“If soybean germplasm can be developed to tolerate temperatures above 85 degrees and then used in breeding programs throughout the southeastern United States, it could ultimately increase soybean yields in the state and region.”

This study is funded until October 31, 2026.