Suma Bai, D ISalu Appan, B2020-11-022020-11-022002171997https://krishikosh.egranth.ac.in/handle/1/5810154084P GI\. research programme was carried out at the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 1999-2000 with the objective of estimating the variability in the important economic characters and the genetic divergence among the accessions in order to group them into clusters based on the magnitude of genetic distance using Mahalanobis 02 statistic. The experiment was conducted using 60 accessions adopting a randomised block design with two replications. Data collected on eleven characters were subjected to statistical analysis. Coefficient of variation, heritability, genetic advance, correlation among the characters, path coefficient and genetic divergence were estimated. Analysis of variance revealed significant differences among the accessions for all the characters except duration of the crop. Phenotypic and genotypic coefficient of variation were high for leaf weight per plant, number of leaves per plant and green fodder yield. I ligh heritability coupled with high genetic advance was observed for plant height, leaf weight per plant, green fodder yield and dry fodder yield. Correlation studies indicated that plant height, number of leaves per plant, leaf area index, leaf weight per plant, dry fodder yield and crude fibre content exhibited significant positive correlation with green fodder yield. vii Leaf weight per plant exhibited the highest positive direct effect on green fodder yield followed by plant height. Number of branches per plant and leaf area index recorded negative direct effect on green fodder yield. Based on the genetic distances computed with respect to ten characters studied, the 60 accessions of fodder rice bean were grouped into five clusters while accessions LRB 235, LRB 221, LRB 225, RBL 118 and LRB 145 remained as single. Maximum divergence was obtained between C4 and CID while divergence was minimum between Cl and C3. Hence, selection of parents from C4 and CIO will be effective [or an overall improvement of fodder yield. viiiEnglishQuantitative variation and genetic divergence in fodder rice bean [Vigna umbellata (Thunb.) Ohwi and Ohashi]Thesis