Heterosis and combining ability for quantitative traits in fodder sorghum (Sorghum bicolor L.)

Abstract

Combining ability and heterosis for some fodder yield and its component traits were studied among nine sorghum crosses and their six parents in a randomized complete block design with three replications under irrigated conditions. Highly significant differences for genotype, general combining ability and specific combining ability were observed for all the characters under assessment. However, general combining ability variances were lower than the specific combining ability variances for all the evaluated parameters. All the traits under study showed greater dominant variance than the additive variance having degree of dominance greater than unity. The sorghum line V-1 indicated the highest general combining ability effects in the desired directions for plant height, TSS-9 for number of tillers plant^-1and CVS-13 for stem thickness, fresh weight plant^-1and dry weight plant^-1. All the nine crosses depicted significant and positive mid-parent as well as better parent heterosis for fresh weight plant^-1and dry weight plant^-1. The present study indicated that improvement in fodder yield is feasible due to overall better performance of genotypes having significant better parent heterosis along with good general combiner parents (CVS—13).