The present investigation was aimed to study the combining ability and gene action in parents and hybrids of sunflower for seed yield and components traits. Six female lines were crossed with four male lines by Line x Tester method, to obtain 24 F1s. Data were recorded on ten characters. Among the female parents CMS-108A, CMS-250A and CMS-207A were good general combiners for seed yield and other contributing traits. Among the male parents, IB-22, EC-178178, EC-601957 were identified as the best

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... general combiners for seed yield and other yield contributing traits. The crosses showing high desirable SCA effect have involved one of the parents of high GCA effect and in turn, had high per se performance. The SCA effect of hybrids viz., CMS-207A x IB-22 and CMS-108A x GP-6-116 were highly significant for seed yield/plant (g) and other component traits in a desirable direction, indicating that the high performance of these crosses is due to non-allelic gene action.Non-additive gene action is predominant for all the studied characters except days to 50% flowering, plant height (cm) and hull content (%).