Combining ability analysis for seed yield and its component traits in sesame (Sesamum indicum L.): A genetic study

Sesame (Sesamum indicum L.) is a vital oilseed crop cultivated extensively in India. Improving sesame yield requires effective breeding strategies that utilize parents and hybrids with strong combining ability. Line × Tester analysis was carried out in sesame to study gene action, combining ability of parents and hybrids, mean performance and to select promising hybrids based on mean, gene action and combining ability effects for seed yield and component traits. A set of six lines (EC358033, EC346664, IC129607, IC204840, IC204557 and VS19078) and three testers (TMV 3, VRI 5 and TMV 7) were crossed using a line × tester mating design. The gene action and combining ability were analysed for ten quantitative traits. All traits showed a preponderance of non-additive gene action. Among lines, IC 129607, IC204557 and VS19078 and testers TMV 3 and TMV 7 had significant and positive GCA effects for seed yield per plant and component traits. The hybrid TMV 7 × IC204557 exhibited high mean performance, significant GCA and non-significant SCA for seed yield per plant, number of capsules per plant and most of the other traits. Hence, this cross can be further handled through pedigree breeding to obtain high-yielding segregants due to the presence of additive gene action. Hybrids, TMV 3 × VS19078, TMV 7 × IC129607, TMV 3 x IC129607, TMV 3 × IC204557 and TMV 7 × VS19078 had high per se, good combining parents, but with significant SCA for seed yield or number of capsules per plant and other component traits. Hence, selection should be postponed to later generations in these crosses due to the presence of non-additive gene action.