Manifestation of heterosis and combining ability for yield and its attributes in sesame (Sesamum indicum L.) using line x tester mating design

Abstract

The present investigation was conducted in sesame to estimate heterosis and combining ability for yield and yield attributing traits using line x tester mating design. Four lines and three testers were crossed to produce 12 F1 hybrids. The heterobeltiosis for seed yield per plant ranged from -16.51 to 24.57%, while the standard heterosis ranged from -12.74 to 33.58% over standard check variety DS-5. Analysis of variance for combining ability revealed that the mean squares due to lines x testers interaction showed significant for all characters. The significant variances due to lines, testers and line x tester showed the involvement of both additive and non-additive gene actions in controlling the traits. General and specific combining ability (GCA and SCA) variances showed major contribution of additive gene action for all the nine characters studied except number of seeds per capsule. AT 238 and JCS 2698 exhibited high gca effects and good per se performance for seed yield per plant and should be utilized in multiple crossing programmes. The sca effect of the crosses indicated that five hybrids manifested significant and positive sca effects for seed yield per plant. Among these, the best three specific combiners were AT 238 x DSS-9, AT 238 x DS-5 and TKG 506 x DSS-9.