Combining ability and gene action for seed yield and its related traits in castor (Ricinus communis L.)

Abstract

The experimental material consisting of 101 entries comprised of ten parents and their 45 hybrids and 45 F2s developed through half diallel mating design and one standard check (GCH 7) were evaluated in a randomized block design with three replications. The analysis of variance for combining ability revealed that general combining ability (GCA) and specific combining ability (SCA) variances were significant for all the eleven characters in both the generations reflecting the importance of both additive and non additive genetic variances for controlling these traits. The ratio of σ2GCA/σ2SCA was more than unity for effective length of primary raceme in F1 generation, while for the rest of the characters the ratio was less than unity in both the generations. Among the parents, PCS 124, JI 353 and JI 368 in F1 generation and JI 353 and DPC 17 in F2 generation exhibited good general combining ability effect for seed yield per plant. The highest yielding hybrid JI 368 x RG 2787 in F1 generation and DPC 17 x SKI 343 in F2 generation had also registered significant positive sca effect for seed yield per plant in both the generations.