Bloomington, Illinois, USA
June 11, 2012
In new research funded by the soybean checkoff, University of Illinois and USDA-ARS researchers are exploring the genetic potential of exotic soybean lines from China to increase yields for United States farmers.
“Yields are a farmer’s biggest concern,” says Dan Farney, ISA production committee chairman and farmer from Morton, Ill. “We haven’t increased soybean yields like we have in corn, so this checkoff research is important to help us meet growing worldwide demand for soybeans while increasing profitability.”
Randall Nelson, USDA-ARS scientist and professor at the University of Illinois, and Brian Diers, professor at the University of Illinois, and their teams are testing genes from old soybean breeding lines from China to look for genes that can increase the yield potential of U.S. varieties. The researchers identified the locations of several genes from the Chinese lines that have a positive impact on yield in U.S. varieties. These genes gave yield increases of 1 to 2 bushels per acre and when stacked together yield increases of 8 to 9 bushels per acre were observed, according to Diers.
“Understanding how genes affect yield involves analyzing a very complex system. There is not just one single area on a soybean chromosome that controls yield, but hundreds of genes,” says Diers. “Our goal in this project was to map the major yield-increasing genes from the exotic Chinese lines with genetic markers so these genes can be used by U.S. soybean breeders. Our data show clear evidence that increased yields can come from exotic germplasm. This type of research helps expand the genetic base of U.S. germplasm, which should lead to better yields and other agronomic characteristics,” he says.
Expanding Genetic Base
Nearly 80 percent of genes in modern soybean varieties can be traced back to just a dozen ancestral lines and their first-generation offspring, according to Nelson. “Our soybean breeding program to incorporate new genetic diversity is designed to increase the rate of yield improvement. This is a long-term approach that ultimately helps Illinois farmers stay more competitive,” says Nelson. “Farmers want to increase yields, and we are attempting to provide the genetics that help reach higher yields and profitability.”
While breeding and genetic mapping with exotic soybean lines have resulted in the development of varieties with resistance to soybean rust, soybean cyst nematode and soybean aphid, increased yield has been out of reach—in part because today’s elite breeding lines are already considerably higher in yield than all exotic lines. “Using lower-yielding parents to increase yield is not a commonly used breeding strategy, but our research clearly shows that lower-yielding exotic lines can have genes that will increase the yield of U.S. varieties,” says Nelson.