Breeding for Greater Stability of Protein and Oil Content in Soybean.
Maria A. Larriera, Univ of Minnesota, Dept of Agron & Plant Genetics, 411 Borlaug Hall, 1991 Buford Circle, St. Paul, MN 55108, Mark Westgate, Iowa State Univ, 3010 Agronomy, Ames, IA 50011, and James Orf, Iniov of Minnesota, Dept of Agron & Plant Genetics, University of Minnesota, 411 Borlaug Hall, 1991 Buford Circle, St. Paul, MN 55108.
The amount of protein and oil in the seeds of soybean accounts for much of the economic value of the crop. As the U.S. domestic soybean market continues to incorporate premiums and discounts for seed composition, the importance of breeding for varieties with high, stable protein and oil seed content will increase. Though Minnesota’s northern climate is favorable for producing high soybean yield, its cooler and fluctuating temperatures are also responsible for lower and more variable protein and oil seed levels than that of soybeans produced in southern states. The objective of this research is to study the stability of yield, protein and oil content in two populations of 312 RIL’s derived by crossing the line PI 132217 (stable protein level), with the cultivars Proto and Lambert. The 312 RIL’s, plus seven check cultivars, were planted in an RCB with three replications at six Minnesota and Iowa locations in 2005. Preliminary results indicate significant effect of genotypes, locations and genotype by location interaction for protein, oil and yield. The stability analysis shows major differences in protein and oil stability among genotypes. In 2006, all the RIL’s will be planted in an RCB with three replications at three Minnesota locations. A subset of 56 RIL’s (chosen because of their high and low protein stability in 2005 trials) plus seven check cultivars will be planted in an RCB with three replications at six Minnesota locations.