Effect of high-oleic acid soybean on seed oil, protein concentration, and yield

Soybeans [Glycine max (L.) Merr.] with high-oleic acid content are desired by oil processors because of their improved oxidative stability for broader use in food, fuel, and other products. However, non-genetically modified organism (GMO), high-oleic soybeans have tended to have low seed yield. The objective of this study was to test non-GMO, high-oleic soybean lines derived from new gene combinations for seed yield and seed composition traits. Soybean lines with ~750 to 800 g kg^-1 oleic acid concentration were generated by combining mutant allele S117N FAD2-1A from 17D and mutant allele P137R FAD2-1B from PI 283327. Also, lines were developed by crossing M23 with a different FAD2-1A mutation × (Jake × PI 283327) and used for comparative purposes. Forty F_4:7 high-oleic lines with these mutant FAD2-1A and FAD2-1B genes were compared with forty F_4:7 normal oleic acid lines (~200-250 g kg^-1) for seed yield, five fatty acids, total oil, and protein concentration from six crosses grown in six environments. The high-oleic genotypes averaged >790 g kg^-1 oleic acid and concentrations of palmitic and linolenic acids were significantly lower (~30% lower) in high-oleic acid lines than in their normal oleic acid counterparts in each environment. When averaged across all locations and populations, seed yield of the high-oleic lines derived from 17D were within 2% of the normal oleic lines but yield between high and normal oleic lines varied among populations. The high-oleic lines averaged significantly higher in protein than normal oleic lines in all six populations. Oil was also higher in the high-oleic lines than normal oleic lines from the 17D populations but was lower in the high-oleic lines derived from M23. Thus, high-oleic soybeans derived by combining mutant allele S117N FAD2-1A allele with mutant P137R FAD2-1B allele can have comparable yields with the potential to generate more oil with greater functionality and a higher protein meal than soybeans with normal oleic acid content.