Assessment of combining ability for seed yield and component traits in Indian mustard (Brassica juncea L.)

A study involving hybrids developed by crossing eight Indian mustard (Brassica juncea L.) lines in diallel fashion, excluding reciprocals, was taken up during Rabi 2022-23, to investigate their combining ability for yield and contributing traits. It was observed that the mean squares attributed to genotypes, encompassing parents, crosses and parents vs. crosses, were statistically significant for all examined attributes. Furthermore, both GCA and SCA components of variance were identified as statistically significant across all the examined attributes. Notably, the genotypes BPR-540-6, BRIJRAJ and DRMR-1165-40 were observed to be good general combiners for seed yield and other yield-attributing traits, indicating their potential utility in breeding programs. The estimates of SCA revealed that specific combining ability effects were both significant and positive for seed yield/plant in the cross combinations of DRMR-150-35 × KRANTI, BRIJRAJ × RH-725 and DRMR-2059 × KRANTI. Based on the per se performance and the noteworthy specific combining ability effect for seed yield/plant, it is recommended that the hybrids DRMR-150-35 × KRANTI and BRIJRAJ × RH-725 be leveraged in heterosis breeding or recombination breeding endeavors to attain higher seed yields.