EVALUATION OF GENETIC DIVERSITY IN WHEAT (TRITICUM AESTIVUM L.) USING MORPHOLOGICAL TRAITS

Abstract

Genetic diversity plays a vital role in wheat improvement by providing the variability required for selection and the development of superior cultivars. The present study was conducted to assess the genetic diversity among 60 wheat (Triticum aestivum L.) genotypes using agro-morphological traits and multivariate statistical approaches. The genotypes were evaluated under an augmented block design at the Research Farm of the Faculty of Agricultural Sciences, SGT University, Gurugram, Haryana. Data were recorded for key agronomic traits and analyzed using analysis of variance, correlation analysis, path coefficient analysis, K-means clustering, hierarchical clustering, heatmap visualization and multidimensional scaling (MDS). Analysis of variance revealed significant variability for leaf rust response, tiller number, and weight per spike, indicating the presence of exploitable genetic variation within the germplasm. Correlation analysis showed strong positive associations of grain yield with tiller number (r = 0.867) and weight per spike (r = 0.865). Path coefficient analysis further identified these traits as the major direct contributors to grain yield, with direct effects of 0.528 and 0.536, respectively. Multivariate analyses consistently grouped the genotypes into two distinct clusters, demonstrating substantial genetic divergence among the evaluated materials. Heatmap and MDS analyses validated the clustering pattern and identified several genetically unique genotypes. Genotypes such as HI1531, MP3224, PBW590, Kharchia65, WH1021, IC42, NP866, and GW451 were identified as promising parental lines for future breeding programmes. The results demonstrate that agro-morphological characterization combined with multivariate analysis is an effective approach for identifying genetically diverse and high-performing wheat genotypes for crop improvement.