Combining ability analysis for yield and its components in aerobic rice (Oryza sativa L.)

Abstract

Line × tester analysis using a set of 4 females (lines) and 12 males (testers) having diverse genetic background was carried out to study the nature and magnitude of heterosis for yield and its components of rice under aerobic condition. Experimental material comprising 16 parents and their 48 hybrids were planted in a Randomized Block Design with three replications during Kharif- 2015 at the Main Rice Research Centre, Navsari Agricultural University, Navsari. Combining ability analysis revealed that both GCA (General Combining Ability) and SCA (Specific Combining Ability) variances were important for inheritance of various traits under study. However, the magnitude of SCA variance was higher than GCA variance for all characters which indicated the predominance of non-additive gene action. The estimates of GCA effects of parents indicated that four parents viz., GR-7, CR DHAN 201, IET 23449 and NAUR-1 which had positive significant GCA effects for grain yield per plant and some of yield contributing characters. Crosses viz., NAUR-1 × CR DHAN 201, Gurjari × GR-7 and GAR-13 × IET 23459 were found to be best specific combination for grain yield per plant and involved good × good, poor × poor and poor × good combining parents, respectively.