Agronomic Evaluation of a High Protein Allele from PI407788A on Chromosome 15 across Two Soybean Backgrounds

Abstract

Soybean [Glycine max (L.) Merr.] protein is a prominent plant-based protein source worldwide due to its high quality and relatively low cost. A major barrier to the development of high protein cultivars is the negative relationship between seed protein and seed yield. A large effect protein quantitative trait locus (QTL) has been mapped to the same location on chromosome (chr) 15 in several studies and given the designation, cqSeed protein-001. The objective of this study was to evaluate the effect of the high protein allele from PI407788A at the chr 15 locus on seed composition and agronomic traits. Populations of near isogenic lines (NILs) segregating for the high protein allele on chr 15 were developed by backcrossing this allele into two elite soybean backgrounds, and these NILs were evaluated at four field environments in Illinois. Across the two backgrounds, the PI407788A allele significantly (P < 0.0001) increased seed protein and decreased seed oil compared to the recurrent alleles but had a nonsignificant effect on yield. Information from this study will aid breeders in forming strategies to develop cultivars with increased seed protein and yield to meet the needs of a growing world population.