Forage Res., 39 (4) : pp. 170-174 (2014) http://forageresearch.in GENETIC VARIABILITY AND HERITABILITY FOR SEED YIELD AND WATER USE EFFICIENCY RELATED CHARACTERS IN CLUSTERBEAN [CYAMOPSIS TETRAGONOLOBA (L.) TAUB.] JITENDER, S. K. PAHUJA*, NARESH VERMA AND NABIN BHUSAL Forage Section, Department of Genetics and Plant Breeding CCS Haryana Agricultural University, Hisar-125 004 (Haryana), India *(e-mail : skpahuja66@gmail.com) (Received : 15 March 2014; Accepted : 28 March 2014) SUMMARY The material for present investigation comprised 25 guar genotypes. The experimental material was grown at Research Area, Crop Physiology (Agronomy), CCS Haryana Agricultural University, Hisar during kharif 2010 in randomized block design with three replications. The mean sums of squares due to genotypes were recorded to be highly significant for all the 18 characters studied, including morpho- physiological, biochemical characters and yield components and seed yield per plant. The studies revealed prevalence of enough genetic variability in the material under study. Characters like pods per plant, dry weight, plant height and proline content in leaves had high GCV, PCV, heritability and genetic advance as per cent of mean. While harvest index and seed yield per plant had high GCV, PCV and heritability associated with moderate genetic advance as per cent of mean. Likewise germination/survival per cent had moderate GCV, PCV and genetic advance as per cent of mean with high heritability. However, 100 seed weight, branches per plant and leaf area index had high GCV, PCV and heritability associated with low genetic advance as per cent of mean. While gum content, rate of water loss from excised leaf, cell membrane stability and seed per pod had moderate heritability associated with low GCV, PCV and genetic advance as per cent of mean, respectively. However, canopy temperature depression and chlorophyll fluorescence had high heritability associated with low GCV, PCV and heritability, respectively. Key words : GCV, PCV, heritability and genetic advance as per cent of mean, guar Clusterbean [Cyamopsis tetragonoloba (L.) Taub.] belongs to the family Leguminaceae and sub- family Paplionaceae. It is an annual with long and deep root and well developed laterals, cultivated mainly as rainfed crop in arid and semi-arid regions during rainy (kharif) seasons for vegetable, forage and green manure. India is one of the main producers of clusterbean accounting for 80 per cent of the total production of the world, whereas Rajasthan occupies the largest area (82.1%) under guar cultivation in the country. Genetic improvement for quantitative traits depends upon the nature and amount of variability present in the genetic stock and the extent to which the desirable traits are heritable. Assessment of the genetic variability within cultivated crops has a strong impact on plant breeding strategies and conservation of genetic resources. It is particularly useful in the characterization of individuals, accessions, and cultivars in determining duplications in germplasm collections and for the choice of parental genotypes in breeding programmes. Yield is a character determined by several component characters. Hence, selection for yield should take into account the related characters also. Genetic variability exists for stress and related traits in guar and is useful in selection of drought resistance genotypes by an efficient screening technique based on a combination of morpho-physiological parameters. MATERIALS AND METHODS The material for the study consisted of 25 genotypes of clusterbean. The experiment was conducted at the Research Area, Crop Physiology, Department of Agronomy, College of Agriculture, Hisar