An assessment of the interaction between sucrose content and seed quality traits in soybeans

Soybean (Glycine max [L.] Merr.) cultivars with increased protein and sucrose content are desirable to enhance soybean meal quality; however, the complex interactions between soybean traits, mainly trade-offs, make the plant breeders' job challenging because traits cannot simultaneously be enhanced. Information about the interactions of seed carbohydrate composition with other seed traits remains inconclusive and contradictory; thus, this study explored the interactions among soluble carbohydrate content with other seed traits, flowering time, and maturity in a diverse panel of 1096 soybean accessions from the USDA Soybean Germplasm Collection. Trait interactions were explored through phenotypic, additive genetic, and residual correlations. We did not identify traits that can be useful in the indirect selection of sucrose. Additive genetic correlations of sucrose with flowering and maturity time suggest that obtaining cultivars with high sucrose content might be easier in earlier flowering and later maturing cultivars. Sucrose correlations with other seed traits were primarily driven by their additive genetic correlations, which make them more stable, whereas correlations of raffinose with oil and maturity were population and environment specific. The two main obstacles to enhancing soymeal quality are the trade-offs of protein with sucrose and oil.