Recent studies conducted by University of Arkansas System Division of Agriculture researchers have found genetic markers in soybeans that could help improve drought tolerance, experts say.

“Drought causes tremendous variability in soybean yield from year to year,” Avjinder Kaler said in a news release.

Kaler is a post doctoral associate with the Division of Agriculture, the Dale Bumpers College of Agricultural, Food and Life Sciences and the Department of Crop, Soil and Environmental Sciences.

“Every year, drought impacts soybean yield in some part of the U.S.,” he said.

Kaler is working with Larry Purcell, who is the lead scientist on this large regional project funded by the United Soybean Board. Purcell is the Altheimer Chair for soybean research with the Division of Agriculture.

Soybean is one of the most widely grown crops in the world. Soybean production had more than a $1.4 million economic impact in Arkansas in 2016, according to the 2017 Arkansas Agriculture Profile. Drought stress can lead to potential soybean yield loss in rain-fed areas. This variation in soybean yields due to drought is projected to get worse with global climate change.

“The goal of our research is to improve the drought tolerance in soybean using genomic and physiological mechanisms,” Kaler said.

The study, Genome-wide association mapping of canopy wilting in diverse soybean genotypes, used association mapping to locate alleles associated with slow canopy wilting. Slow canopy wilting is a trait that has been directly related to yield improvement under drought conditions.

Slow canopy wilting also has a high heritability and is a relatively inexpensive trait for drought tolerance, Kaler said.

Kaler said the alleles he has identified in his research associated with slow canopy wilting can help improve soybean drought tolerance by transferring those alleles to high-yielding, drought-sensitive cultivars using non-transgenic breeding methods. The breeding process is accelerated because molecular markers are used to identify the favorable alleles during the breeding process. The first crosses to move the slow-wilting alleles to a high-yield line were initiated this summer.

Kaler’s began this research in 2013 for his PhD dissertation project. In addition to Kaler and Purcell, other investigators in the study include Jeffery Ray, USDA research geneticist; Jason Gillman, USDA research geneticist; Rusty Smith, USDA soybean breeder; Hussein Abdel-Haleem, USDA research geneticist; Felix Fritschi, University of Missouri crop scientist; William Schapaugh, soybean breeder at Kansas State University; Andy King, program director for Crop, Soil and Environmental Sciences at the University of Arkansas.


The University of Arkansas System Division of Agriculture offers all its Extension and Research programs to all eligible persons without discrimination.

— Emily Thompson is with the U of A System Division of Agriculture.