Combining ability and gene action studies for seed yield and its components in Sunflower (Helianthus annuus L.)

Five CMS lines and six restorers were crossed in a line x tester fashion to elucidate the information on the combining ability for seed yield, yield components and oil content and also to know the nature of gene action involved in inheritance of important quantitative traits. A total of 30 crosses were evaluated for 13 different quantitative traits. Line CMS E002-92-2 and CMS-104A exhibited significant gca effects for most of the characters studied and were found to be the best combiners. Likewise, tester EC-623015 was the best combiner for seed filling per cent, seed yield per plant, harvest index, volume weight, kernel per cent, hull per cent, KH ratio and oil content. The estimates of variance components revealed predominance of non-additive gene action for all characters studied.