Combining ability analysis of yield and its components in linseed (Linum usitatissimum L.)

Combining ability analysis of yield components was worked out using diallel mating design to chalk out the nature and magnitude of gene action and to isolate good combiners for improvement of linseed. The experiment was conducted at Students ’Instructional Farm, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur during rabi 2009–20. The significance of gca and sca variances reflected the importance of both additive and non-additive gene actions for plant height, number of primary branches plant⁻¹, number of secondary branches plant⁻¹, number of capsules plant⁻¹, 1000-seed weight and seed yield plant⁻¹. However, the estimates of sca variances (δ² s) were lesser than gca variance (δ² g) showing predominance of additive gene action in the inheritance of traits. Average degree of dominance (δ² s/δ² g)^0.5 showed partial dominance for all the characters. Parents Shubhra, EC 1424 and TL 27 were found to be good general combiners for number of capsules plant⁻¹, seed yield plant⁻¹ and 1000-seed weight over the generations. Cross Shubhra x JRF 5, FRW 1 x EC 1424, Shubhra x Ayogi, Shubhra x FRW 1 and FRW 1 x TL 27 were the most promising crosses over the generations for improvement of seed yield.