Evaluation of Combining Ability and Heritability Estimates of Quantitative and Qualitative Traits in Sunflower (Helianthus annuus L.) Lines

In order to evaluate combining ability and heritability of quantitative and qualitative traits in sunflower (Helianthus annuus L.) lines, three testers and four lines were crossed using line × tester fashion. The 12 F1 single cross combinations along with their parents and five checks including Azargol, Alestar, Euroflor, SHF81-85 and SHF81-90, totally 25 genotypes were planted in simple lattice design with two replications at Dashtenaz Agronomy Research Station in 2008. The traits including plant height, head diameter, lifecycle duration, grain yield, 1000 grain, weight, oil content and oil yield. Estimation high narrow sense heritability for 1000 grain, weight indicated the more importance of additive genetic effects for its genetic control. The tester T2(AF81-40) and line L1 (RF81-154/2) with significant positive general combining ability (GCA) effects for grain and oil yields were considered as suitable combiners for improving these traits. T1 (AF81-178) with significant negative general combining ability for plant height was suitable for decreasing this trait. The crosses including AF81-222×RF81-053/2, AF81-178×R4 and AF81- 178×RF81-106/1 had significant negative specific combining ability (SCA) effects for plant height were good combinations for improving this trait. The cross AF81-40×RF81- 154/2 had significant positive SCA effects for 1000-grain weight. This cross combination had also significant positive SCA effects for grain yield and oil yield and also high means value of these traits.