Research HighlightsIncreasing Soybean Genetic Gain for Yield
By Barb Baylor Anderson
Soybean yield increases achieved through breeding are substantially less than those for corn. In fact, a collaborative study of varieties released from 1923 to 2008 revealed a rate of genetic gain of only 0.43 bushels per acre per year. Soybean farmers are working together to change that.
Researchers from several key soybean production states are involved in a checkoff-funded research project with the North Central Soybean Research Program (NCSRP). Started in 2017, the goal is to develop tools, know-how and community among public breeders to increase genetic gain for better yield in breeding and higher yield potential in soybean varieties.
“Increasing genetic diversity of breeding programs will increase ability to genetically improve soybeans. However, the increase in diversity needs to be carried out in an informed manner so that poor genetic backgrounds do not decrease overall yields,” says Leah McHale, soybean breeder and geneticist with Ohio State University and a principal investigator on the project.
McHale says researchers have collaborated so far to take public uniform trial results, place them in a development database that has phenotypic data from the northern regional uniform trials as well as genotypic data (6k SNP chip) from most lines that were entered in the tests and use the data to create models for genomic selection to decrease time for each cycle of selection relative to traditional phenotypic selection. Once complete, the database will be public and searchable. Researchers also have developed an inexpensive and high-throughput genotyping platform that makes genomic selection available and feasible for public breeding programs.
“As part of this project as well as another previously funded by NCSRP, we characterized 500 accessions from the USDA Soybean Collection and evaluated how well genetic models developed from these accessions could predict yield and agronomic characters of other accessions in the collection,” says McHale. “Characterization included yield and agronomic traits evaluated over two years across the North Central region, representing one of the largest and most in-depth characterizations of the collection ever.”
Additional methods to increase diversity included identification and characterization of key genes for maturity, branching and other domestication traits, she adds. Markers for those genes will help speed introduction of exotic alleles into elite, adapted genetic backgrounds.
Finally, researchers have identified alleles potentially associated with yield from an alternative germplasm pool. The alleles could represent valuable alleles absent from current elite cultivars or provide selection targets to introduce exotic alleles into elite, adapted genetic backgrounds.
“This year, we also are educating soybean breeders, including students and scientists, about the concept of genomic selection,” says McHale. “We are working on making our database publicly accessible, developing models to test and establish best practices for implementing genomic selection and implementing ‘rapid cycling’ genomic selection methods.”
McHale says the timeframe to observe genetic gain in the field is ultimately hinged to the time it takes to develop a new cultivar and increase seed, which is around seven years.
Photos: United Soybean Board
To find research related to this Research Highlight, please visit the National Soybean Checkoff Research Database.