Clemson scientists study heat stress, which directly reduces peanut yield, causes other problems indirectly.
A group of researchers led by Clemson University Plant and Environmental Sciences assistant professor Sruthi Narayanan is working to develop heat-tolerant peanut varieties. Their latest work focuses on how lipids (fats) in peanut plant anthers are altered by heat stress.
“Understanding these changes will aid in understanding the mechanisms of heat tolerance and help us determine how to develop heat-tolerant peanut varieties,” Narayanan says.
Lipids provide energy for plant growth and survival. Anthers are plant male reproductive organs that produce pollen, which is transported to the stigma of the female reproductive organ in the flower, pistil, for pollination to occur and plants to reproduce.
Reduced Pollen, Reduced Yield
“Reduced pollen production and viability are the major reasons for yield loss when heat stress occurs during the flowering stage,” says Zolian Zoong Lwe, a former Clemson master’s student who conducted the study under Narayanan’s guidance and is now a doctoral student at Kansas State University. “Understanding the mechanisms underlying the decrease in pollen during heat stress will help develop tolerant peanut varieties.”
The study, funded by the National Peanut Board, the South Carolina Peanut Board and supported by the U.S. Department of Agriculture National Institute of Food and Agriculture, began in 2018. It involved six varieties: Bailey, Georgia 12Y, Phillips, Sugg, Tifguard, and Wynne and one breeding line, SPT06-07.
“These varieties were selected to have a range of cultivars from heat sensitive to more heat or drought-tolerant,” says Dan Anco, Clemson Extension peanut specialist and assistant professor at the Edisto Research and Education Center in Blackville, South Carolina, and one of the researchers on the study.
Test varieties were grown in fields at the Simpson Research Farm following field operation recommendations in the Clemson Peanut Money-Maker Production Guide. The plots received rainwater only.
Traits For Heat Tolerance Found
Heat tents were used to heat-stress the plants for 17 days in 2018 and 18 days in 2019. Lipids were extracted from anthers in flowers collected from the plots. Researchers found heat stress caused changes in lipids needed for the plants to reproduce.
The study identified lipid metabolic traits associated with heat tolerance.
“This discovery is useful in determining lipid biomarkers (measurable/observable changes) that have important applications in breeding climate-resilient varieties,” says Sachin Rustgi, a plant breeder at the Clemson Pee Dee REC in Florence who also is part of the research team.
Other researchers involved in the study are Salman Naveed, a doctoral student at Clemson University, and Ruth Welti, a biology professor at Kansas State University.
A paper about their study appears in the scientific reports journal’s Dec. 17, 2020, edition of Springer-Nature.
According to USDA’s National Agriculture Statistics Service, South Carolina had 62,000 acres of peanuts at a production value of more than $46 million in 2019 and 82,000 acres that produced 278 million pounds of peanuts in 2020. PG
Article by Denise Attaway, Clemson University Communications.