Combining Ability Analysis for Grain Yield and Its Related Characters in Rice (Oryza sativa L.)

Ten diverse genotypes of rice (Oryza sativa L.) were crossed in a diallel fashion to study gene action as well as their combining ability for 12 quantitative characters combining ability analysis suggested that additive gene action were involved in the inheritance of days to 50% flowering, days to maturity, plant height, number of leaves per tiller, number of spikelet per panicle. Non additive gene action was predominant for panicle length, panicle number per plant, 1000 grain weight, grain yield per plant, straw yield per plant, total biological yield and harvest index. Among the parents, I.R. 50, Ratna, Saket 4, Pusa 150 showed significant gca effects for more than one desirable trait indicating their utility in heterosis breeding programme. The hybrids Govind x Jaya, Basmati 370x Pusa 150, showed significant and positive sca effects.