Analysis of Genetic Diversity in Genotypes of Greengram [vigna Radiata (L.) Wilczek]

Abstract

The present investigation comprised of 39 genotypes of greengram to analyze genetic diversity and molecular characterization for 13 quantitative traits. Analysis of variance showed that the differences in genotypes were very significant for all the traits. High to moderate GCV estimates and high heritability coupled with high genetic advance as percent of mean were observed for the all the traits except characters-days to 50% flowering, days to maturity, pod length, number of seeds per pod and number of cluster per plant indicating the preponderance of additive gene action. Seed yield per plant had a highly significant and positive correlation both at genotypic and phenotypic levels with number of pods per plant, number of cluster per plant, biological yield, pod length, number of pod per cluster, number of seeds per pod, harvest index, number of seeds per pod, plant height, days to maturity and number of branches per plant which implies that these characters were the prime contributing factors to seed yield. Genotypic and phenotypic path coefficients analysis of seed yield per plant and its component attributes showed that highest positive direct effect towards seed yield per plant was observed by number of pods per plant, number of cluster per plant, biological yield, pod length, number of pod per cluster, number of seeds per pod, harvest index, number of seeds per pod, plant height, days to maturity and number of branches per plant. Seed yield per plant could be improved by selection based on these traits. Based on D2 values 39 genotypes of mungbean were grouped into five clusters. Based on molecular characterization 15 SSR primers were amplified with 38 genotypes of mungbean out of which only 9 SSR primers have shown polymorphism. These SSR primers had polymorphic information content ranging from 0.96 (VrM004) to 0.02 (VrM008) with a mean PIC value of 0.37. Dendrogram was constructed based on 9 SSR primers (ranging from 0.58 to 1.00) which were grouped the genotypes into two major clusters. Based on dendrogram, result from field data and molecular data exhibited following two genetically diverse group of genotypes namely- IPM-99-125, IPM-2057, LM-95 (group 1) and PM-6, UPM-02-17, IPM-2-3, RMG-353, PM-2, INDOR-MUNG, PM-9, ML-729, SUKETI-1, PM-8, IPM-214, IPM-302-20, SML-1815 (group 2) Such screened genotypes can be further used in further introgressions of specific traits from one group to another group of genotypes.