Heat stress-resilient soybeans
The optimum temperature for soybean production is around 80-degrees. If temperatures climb higher, it negatively impacts seed yield and seed composition, especially during the critical post-flowering stage of development. It can reduce the number of pods set, and temperatures above 90-degrees severely limit grain weight and seed composition. This is often exacerbated by a lack of soil moisture.
Researchers at Kansas State University and the University of Missouri have started a three-year effort to develop soybean cultivars that will better withstand heat stress during that period of growth.
The team is led by Kansas State agronomy professor and soybean breeder Bill Schapaugh. He says they are studying 300 genetically diverse genotypes. Some are being grown normally, others under large heat tents.
"In 2020 and 2021, we will compare the response of the genotypes grown under the heat tents to plants growing in the surrounding area. We’ll be looking at seed yield, yield components, seed composition like protein and oil, and seed germination," says Schapaugh. "The phenotypic data from the first two years will be used to discover genomic regions and do some heat stress tolerance."
In the next phase, they will take a subset of the 300 genotypes for a more intensive evaluation of gene candidates for heat stress tolerance.
"In 2022 we’ll add experiments to further characterize plant and seed development of the more novel genotypes and share this information on the genetic variation for heat stress tolerance with commercial breeders so it can serve as a foundation for variety development in the future," he says.