Morphological Characterization of Groundnut (Arachis hypogaea L.) Accessions Using DUS Descriptors

Abstract

Groundnut (Arachis hypogaea L.) is a vital legume crop, contributing to food and oil security and supporting nutritional needs in developing regions. This study evaluated 54 groundnut germplasm accessions for genetic variability and characterization using the Distinctness, Uniformity, and Stability (DUS) framework, following National Test Guidelines and UPOV regulations. The field trial, conducted during the Kharif season of 2025 at MallaReddy University, School of Agricultural Sciences, Hyderabad, Telangana, India, employed an alpha-lattice design with two replications. Twenty-one key traits including plant morphology, pigmentation, flowering, pod structure, seed testa and kernel colour, kernel shape, and 100-kernel weight were recorded. Substantial phenotypic variation highlighted the rich genetic diversity among accessions. Hierarchical clustering based on Gower’s distance grouped the genotypes into four distinct clusters, with branches and genotype labels colour-coded for clear visualization. This clustering revealed both intra- and inter-group divergence, offering a practical guide for selecting diverse and promising parental lines. The integration of traditional DUS descriptors with multivariate clustering provides a robust framework for germplasm conservation, precise variety identification, and breeding programs aimed at improving productivity, disease resistance, and climate adaptability in groundnut.