Genetic variation studies among physiological characters in Cyamopsis tetragonoloba (L.) under rainfed condition of Jaisalmer district Rajasthan, India

The multiple plant traits associated with drought were assessed in 21 genotypes of cluster bean including check RGC-936 for their contribution to rainfed adaptation of the genotypes. All the assessed traits showed significantly different genotypic responses under rainfed conditions. Clusterbean genotypes showed wide range of variability for most of the characters and all the traits exhibited broad spectrum of ranges during both years. Total sugar content, specific leaf area at 30 and 45 DAS, number of branches plant¹, number of clusters plant¹, number of pods cluster¹ and seed yield plant⁻¹ showed high genotypic (Vg) and phenotypic (Vp) variances. The high estimates of heritability coupled with high values of genetic advance over mean (GAM) were observed for the characters such as total sugar content, specific leaf area at 45 DAS, clusters plant⁻¹ and seed yield plant⁻¹ indicates predominance of additive component for these traits and hence direct selection would be more effective in improving these traits. Correlation study revealed that number of clusters plant⁻¹ (0.81**, 0.84**), number of pods cluster¹ (0.69**, 0.86**), pod dry weight (0.99**, 0.67**) showed positive significant correlation with seed yield plant⁻¹ during both the years which indicates strong association of these characters with seed yield plant⁻¹. On the basis of above findings, it can be concluded that the characters like, number of clusters plant⁻¹, number of pods cluster¹, showed positive significant correlation with seed yield plant⁻¹. Thus, these traits may be considered as effective parameters of selection to increase seed yield of clusterbean under rainfed situation of Jaisalmer.