SSR Polymorphism and Genetics and Inheritance of Yield and Yield -Attributing Traits In Bitter Gourd (Momordica charantia L.)

The present study was conducted to ascertain the gene action and inheritance of yield and various yield-attri­bu­ting traits and to screen the simple sequence repeat (SSR) markers for parental polymorphism in bitter gourd (Momordica charantia L.). Two contrasting parents (S-2 and Pusa Purvi) were used for hybridization. Parental polymorphism was analysed using 100 SSR markers. DNA amplicon of size around 150–250 bp in both the parents was obtained for the 10 polymorphic SSR markers. These were used to ascertain the hybridity of F₁ progeny, from which the subsequent generations were developed. Generation mean analysis, ABCD scaling test and joint scaling test were performed using the observations from six generations (parent-1, parent-2, F₁, F₂, back cross 1 and back cross 2). The additive effect of the genes was predominant for the quantitative traits like fruit length, diameter, weight, etc. Duplicate epistasis was observed for the majority of traits. The yield per plant was positively correlated with fruit length, diameter, weight and fruit number per plant. Chi-square test revealed the monogenic inheritance of qualitative traits (fruit tubercles and ridgeness, and shape at apex), in which ‘conspicuous tubercles’, ‘discontinuous ridgeness’ and ‘acute fruit shape at apex’ were dominant. These results reveal the complexity and polygenic nature of the yield. The findings obtained from the present study can be used for yield improvement in the future. For this, the polymorphic SSRs identified can also be used in genetic diversity studies, DNA fingerprinting, genetic mapping, genomics analysis, etc.