Hilum Color Variation in Soybean Seed with Imperfect Black Genotype 1

Hilum color of soybean [ Glycine max (L.) Merr.] seed is one of the traits commonly used to differentiate offtypes for seed certification. Variation in hilum color in imperfect black genotypes has resulted in difficulty in classification. The objective of this research was to determine the accuracy of visual classification of hilum color in genotypes with imperfect black hila. Seeds with buff hila were selected from the cv. ‘Pickett 71’ which normally produces seed with imperfect black hila. Forty‐two percent of the plants grown from these seeds produced plants that had seeds with typical imperfect black hila which were the Pickett 71 genotype. Progeny tests showed that the remaining 58% were offtypes. These data clearly showed that visual selection of buff offtypes from the Pickett 71 cultivar was not an accurate method of identifying hilum genotypes. Plants must have gray pubescence, purple flowers, and the R gene to produce seeds with imperfect black hila; therefore, certain offtypes can be quickly identified by growing seedlings and observing hypocotyl color. Seedlings with green hypocotyls will produce white flowers. Seeds that produce seedlings with green hypocotyls definitely are not imperfect black genotypes, but seeds with buff hila that produce seedling with purple hypocotyls may not be offtypes.