PINK FLOWER COLOR ASSOCIATED WITH INCREASED PROTEIN AND SEED SIZE IN SOYBEAN

Most soybean [Glycine max (L.) Merr.] cultivars and plant introductions have either purple (WI) or white (W1) flowers. Pink (wp) flower color results when the homozygous wp alleles are combined with W1. This study was conducted to determine the effect of pink flower color on agronomic traits in soybean. Pink and near-isogenic purple-flowered lines were derived from an F-4 plant. Seven homozygous pink-flowered, three homozygous purple flowered, and two lines segregating for pink and purple flower color were evaluated at three locations in Illinois for 2 yr. When pink flowered lines were compared to purple-flowered lines no differences were found for yield, maturity, height, lodging, or seed quality, while significant (P < 0.05) differences were found for seed weight, protein, and oil concentration. Pink-flowered lines averaged 22% higher in seed weight, 4% higher in protein, and 3% lower in oil compared to the purple-flowered lines. The pink flower trait represents unique germplasm in soybean that can be used in the development of high yielding cultivars with in creased seed protein.