Morpho-biochemical Characterization and Multivariate Assessment of Genetic Diversity in Rajmah (Phaseolus vulgaris L.) Genotypes from Northeast India

Abstract

The present study assessed morphological, yield, and biochemical diversity among forty rajmah (Phaseolus vulgaris L.) genotypescollected from five north eastern states of India, representing both vine and dwarf growth habits. Field experiments were conductedduring the rabiseasons of 2022–23 and 2023–24 at Assam Agricultural University, Jorhat, using a randomized block design with threereplications. Eighteen traits were studied, including ten morphological and eight biochemical parameters and were evaluatedthrough univariate and multivariate analyses. Analysis of variance revealed highly significant genotypic differences for all traits,indicating substantial genetic variability. Vine types exhibited greater plant height, branching, pod number, and seed yield, whereasdwarf types recorded higher 100-seed weight and superior nutritional attributes, including fat, fibre, niacin, vitamin B₆, and folic acid.Correlation analysis showed strong positive associations between yield and key plant architecture traits. Principal component, cluster,and heatmap analyses grouped genotypes primarily by growth habit and regional origin. The outcomes of the study signify richgenetic diversity in the rajmah germplasm of Northeast India and identify key traits for simultaneous improvement of yield andnutritional quality.