Assessment of combining ability and standard heterosis through diallel analysis in sesame (Sesamum indicum L.)

Sesame is a drought tolerant oilseed crop with highest oleic acid content, which is yet to be explored for its hybrid vigour. With the view of producing elite hybrids, combining ability in sesame was studied among five sesame genotypes through diallel analysis. A set of 20 F1’s and their parents were evaluated at Plant Breeding Farm, Faculty of Agriculture, Annamalai University in RBD design with three replications. For this study, estimation of combining ability of seed yield traits viz., the number of days to 50% flowering, plant height, the number of branches per plant, the number of capsules per plant, capsule length, the number of seeds per capsule, 1000 seed weight and seed yield per plant were recorded from five randomly selected plants in each replication. Among the parents, TMV 5 and TMV 3 were adjudged as superior for seed yield per plant and most of the characters. Among the hybrids, TMV 3 / TMV 5 and TMV 3 / VRI (SV) 2 were identified as best performers since these hybrids had desirable per se performance for all the eight characters studied followed by TMV 3 / TMV 6 and TMV 6 / TMV 3 for seven characters including seed yield per plant. The combining ability variance revealed the preponderance of additive gene action for all the characters studied. Based on sca effects, the hybrid VRI (SV) 2 / TMV 3 was considered as the best performing hybrid followed by TMV 3 / TMV 5 and TMV 3 / TMV 6, which could be further utilized in hybrid development in sesame. Considering standard heterosis, hybrids, TMV 3 / TMV 5, TMV 3 / TMV 6, TMV 5 / TMV 3 and TMV 6 / TMV 3 found to be the better performing. Comparing per se, sca and standard heterosis VRI (SV) 2 / TMV 3 observed to be the best along with the hybrids TMV 3 / TMV 5 and TMV 3 / TMV 6 as the better hybrids.