Study on the determination of combining abilities of inbred lines for hybrid breeding using line x tester analysis in sunflower (Helianthus animus L.)

Abstract

Combining ability studies in oilseed sunflower were undertaken with a set of 5 × 4 line × tester including parents for the characters seed yield, 1000seed weight, days to flowering, days to physiological maturity, plant height, head diameter, stem diameter, oil content, fatty acid content (oleic, linoleic, palmitic, and stearic acids), protein content, seed length, seed width, and hull percentage. General (GCA) and specific combining abilities (SCA) and heterosis of inbred lines and their hybrids were estimated in a line x tester analysis during the first and second crop production seasons in Menemen, Izmir, Turkey. The variances due to GCA and SCA were highly significant for most of the characters in both environments. The ratio (H/D)l/2 and σ 2 GCA/ σ 2 SCA depicted the preponderance of non-additive type gene action for all the characters except plant height, head diameter, seed length, palmitic acid content, and stearic acid content. However, both types of gene action were observed for seed yield, hull percentage, 1000-seed weight, oil content, and stem diameter at stem curve point. In this study, GCA effects were found to be highly significant for all traits, while SCA effects were non-signiflcant for most of the traits. Based on GCA effects in the first and second crop production seasons, the inbreds 0043 cms, 0046 cms, 0195 cms, 0583 cms, 0704 cms, 0708 Rf. 0845 Rf, 0951 Rf, and 1097 Rf exhibited desirable GCA effects and were found to be good general combiners for most of the traits. Thus, they can be exploited by further breeding for developing superior genotypes and hybrids in sunflower.