Abstract

                                In the present study, information on the magnitude of combining ability was obtained for grain yield and its components following diallel analysis excluding reciprocals involving ten elite genotypes of sorghum. The 45 F1s, 10 parents and one standard check were tested in randomized block design with three replications at Navsari Agricultural University, Waghai. Analysis of variance revealed presence of considerable variability among genotypes. Combining ability analysis revealed importance of both additive and non additive variances in the expression of various traits. Additive gene action was predominant for grain yield and its related traits. The per se performance of parents for various traits in general was associated with high GCA effects. Similarly close association between hybrid performance and SCA effects was observed. Parents SR 1718, SR 1571, SR 770 and SPV 1022 were observed as good general combiners for yield and its attributing traits. While in respect of hybrids, crosses SR 770 x SPV 1022, GMRP 9 x SR 1571, SR 833 x GMRP 27 and SR 833 x GMRP 9 had exhibited higher SCA effects with higher mean values. The parents with good GCA offer the best possibilities of exploitation for the development of improved lines with enhanced yielding ability. The crosses with high SCA which had at least one parent with high GCA could be successfully exploited for varietal improvement. Recurrent reciprocal selection may be useful to handle such materials

Key words : Sorghum, GCA, SCA, heterosis, yield improvement