Studies on Combining Ability for Yield and Its Component Traits in Rabi Sorghum [Sorghum bicolor (L.) Moench]

The study was carried out to assess the general combining ability of the parents and specific combining ability of the hybrids, using line x tester mating design. Fifty hybrids (derived from mating two testers with twenty-five lines in L x T design) along with their parents and checks (M35-1, BJV 44 and PKV Kranti) were evaluated during the rabi 2018-19. The ratio of σ2 GCA/σ2 SCA was less than unity for all the characters except for panicle indicating preponderance of non-additive gene action. Among female parents M 31-2A was the best combiner for grain yield per plant, number of seeds per plant and 100 seed weight and 104A for panicle length. Among male parents, IS 995, IS 19450, IS 23590 and IS 23891 were found to be the best general combiner for grain yield per plant and number of seeds per panicle. The cross combinations viz., M 31-2A × IS 11619 and M 31-2A × IS 32439 exhibited highest and positive sca effects for grain yield per plant.