Estimation of Combining Ability of Rapeseed Advanced Lines for Yield and Yield Components

To estimate the narrow-sense heritability and combining ability of seed yield and yield components, half diallel crosses of eight oil seed rape lines L41, Zafar, L56, L31, L22, LF2, L420 and L401 along with their parents were evaluated based on randomized complete block design with three replications. The results of diallel analysis revealed significant mean squares for general and specific combining abilities (GCA and SCA) in all traits except 1000-seed weight, indicating the importance of additive and non additive genetic effects for these traits. Estimation of high narrow-sense heritability for pods length (0.50), 1000-seed weight (0.69), seed yield (0.63) and harvest index (0.53) indicated the prime importance of additive genetic effects for these traits. Parents L41, Zafar and L22 with significant positive GCA effects for seed yield were determined as superior parents. The crosses with significant positive SCA effects for seed yield had at least one parent with significant positive GCA effects for this trait. The crosses L41× L22, L41×LF2, Zafar×L22 and Zafar×L420 with seed yield of 3421.7, 3400, 3348.1 and 3311.3 kgha-1, respectively were superior combinations.