Abstract

                                The present investigation was aimed to study the combining ability and geneaction in parents and hybrids of sunflower for seed yield and componentstraits. Six female lines were crossed with four male lines by Line x Testermethod, to obtain 24 F1s. Data were recorded on ten characters. Among thefemale parents CMS-108A, CMS-250A and CMS-207A were good generalcombiners for seed yield and other contributing traits. Among the maleparents, IB-22, EC-178178, EC-601957 were identified as the best generalcombiners for seed yield and other yield contributing traits. The crossesshowing high desirable SCA effect have involved one of the parents ofhigh GCA effect and in turn, had high per se performance. The SCA effectof hybrids viz., CMS-207A x IB-22 and CMS-108A x GP-6-116 were highlysignificant for seed yield/plant (g) and other component traits in a desirabledirection, indicating that the high performance of these crosses is due tonon-allelic gene action.Non-additive gene action is predominant for all thestudied characters except days to 50% flowering, plant height (cm) and hullcontent (%).

Key words : Sunflower; Combining ability; Gene Action;GCA; SCA; Line; Tester