Genetic Variability and Correlation Analysis among Guar Genotypes for Fodder Yield and Quality Related Traits
Abstract
Limited genetic variability remains a major constraint to genetic improvement in guar (Cyamopsis tetragonoloba L.) restricting both its productivity and cultivation in Pakistan. As a drought adapted legume with significant value as fodder, green manure, and a soil-enhancing nitrogen fixer, guar holds considerable untapped potential for sustainable agriculture. Enhancing its genetic base is therefore essential for developing high-yielding, nutritionally superior varieties suited to arid and semi-arid environments. To address this need, a field experiment was conducted in October 2022 at the University of Agriculture, Faisalabad, using a Randomized Complete Block Design (RCBD) with three replications to assess genetic variability and trait associations among 24 guar genotypes. Five plants per genotype were evaluated for agronomic traits (plant height, branches, tillers, leaves, leaf area, clusters plant⁻¹, pods cluster⁻¹, pods plant⁻¹, fresh and dry biomass) and forage quality attributes (crude protein, crude fiber, ash, moisture, NDF, and ADF), with quality traits quantified via Near Infrared Spectroscopy (NIRS). Significant phenotypic variability was recorded among genotypes. Plant height ranged from 78–141.2 cm, branches 2.16–10.06, leaves 44.87–330.33, fresh biomass 200–700 g, dry biomass 70–244 g, and crude protein 15.16–23.37%. Plant height showed strong positive correlations with fresh biomass, leaf area, and crude protein, whereas branches and clusters exhibited negative associations. Tillers were positively correlated with several yield components but not with leaf area or protein. Crude protein was positively associated with NDF, ash, and crude fiber. Superior genotypes identified included Guar-401 (plant height), Guar-303 and Guar-701 (number of branches), Guar-102 and Guar-701 (number of leaves), and Guar-103 and Guar-803 (protein). These high performing genotypes provide valuable genetic resources for developing improved guar cultivars with enhanced fodder yield and nutritional quality.