THE ANALYSIS OF HERITABLE VARIATION FOR THREE AGRONOMIC TRAITS IN A 6-VARIETY DIALLEL OF GRAIN SORGHUM, SORGHUM VULGARE PERS.
Analysis of a six-variety diallel indicates that both general and specific combining ability were important for anthesis time and that specific combining ability seems more important for grain yield. Significant interactions were observed between general combining ability and locations for yield, anthesis time, and protein content while significant interaction between specific combining ability and locations was observed for protein content only.For grain yield, overdominance was indicated by the (H1/D)½ ratio; at least four groups of genes were involved in controlling yield. Heritability estimate was slow. For anthesis time, a partial dominance was indicated. Approximately three groups of genes controlled anthesis; heritability estimate was high. For protein content, a partial dominance was noted. Two groups of genes were estimated for control of protein content; heritability estimate was intermediate.The regression coefficients for the three characters were less than 1, but only that for protein content was significantly so. The deviation of the regression line from unit slope may indicate the ptesence of either epistasis or correlated gene distribution or both in the materials tested.