COMBINING ABILITY FOR YIELD RELATED TRAITS IN BRASSICA JUNCEA

A diallel experiment was conducted to determine better general and specific combiners in 8x8 Brassica juncea L., genotypes for seed yield and its associated traits. Analysis of variance revealed highly significant (p <= 0.01) differences among all the genotypes for pod length, 1000 seed weight and seed yield plant(-1), while significant (p <= 0.05) differences were noted for pods plant(-1) and seeds pods(-1). According to combining ability analysis, the general combining ability (GCA) mean squares was highly significant (p <= 0.01) for seed yield plant(-1) and significant (p <= 0.05) for 1000 seed weight, while found non significant for pods plant(-1), pod length and seeds pod(-1). The specific combining ability (SCA) and reciprocal combining ability (RCA) mean squares were highly significant (p <= 0.01) for all the traits except seeds pod(-1). GCA effects were of greater magnitude than SCA and RCA for pods plant(-1), pod length and seed yield plant(-1) indicating that these traits were controlled by additive type of gene action. Reciprocal effects were found greater than GCA and SCA for seed pod(-1) and 1000 seed weight showing that maternal effects were also active and need due attention for the said traits. The parental genotypes MYT009, MYT113, MYT123, MYT120 and MYT117 were found the best general combiners, while hybrids MYT117 x MYT123, MYT113 x MYT009, MYT123 x MYT113, MYT124 x MYT117, MYT105 x MYT103 and MYT113 x MYT120 were found the best specific combiners for majority of the traits and could be exploited through further selection in segregating population. Results revealed the importance of both additive and nonadditive genetic variability suggesting the use of integrated breeding strategies which can efficiently utilize the additive as well as non-additive genetic variations.