Genetic Diversity, Combining Ability and Heterosis in Brown Mustard

Abstract

Genetic diversity and combining ability were studied in Indian brown mustard. A set of 50 geographically diverse (including 10 genetically diverse lines) lines were characterized for seed yield and their component traits. The 50 lines were grouped into nine clusters based on diversity estimates. The clustering pattern suggested that geographical diversity of a line to not necessarily an index of its genetic diversity and that selection of parents based on their diversity estimates may be useful in a cross breeding programme. The study also pointed out the predominant role of non-additive gene action for major yield traits and ways are discussed to exploit heterozygosity for heterosis breeding in this crop. In general, the performance of lines for seed yield was reflected fa their crosses. The significantly high specific combining ability effects of crosses indicated that degree of genetic diversity among lines is related to their breeding value and to the overall ability to produce heterosis.