Abstract

Line x tester analysis using a set of three females (Lines) and eight males (testers) was carried out to estimates the extent of combining ability for yield and its components in rice (Oryza sativa L.). Experimental material comprising eleven parents, their twenty four hybrids were planted in a randomized block design with three replications during kharif 2007 at the National Agricultural Research Project farm, Navsari Agricultural University, Navsari. Combining ability analysis revealed that, sca variances were higher than gca variances for all the characters except days to maturity which indicated non-additive gene action in the expression of the traits, although non-additive gene action was predominant in the expression of most of the traits. The estimation of gca effects for parents indicating that males Sathi 34-36, GR-5 and female Jaya were the best general combiners for grain yield per plant and some yield contributing traits. The best specific crosses combinations are GR-11 x Sathi 34-36, Jaya x GR- 103 and Jaya x IR-28 of either average x good, good x poor or good x average combination.

Keywords: Rice, Line x Tester, GCA and SCA, Gene action.