Multivariate analysis based on drought tolerance indices for screening drought tolerance in common bean (Phaseolus vulgaris L.)

Abstract

Twenty common bean (Phaseolus vulgaris L.) genotypes were evaluated based on drought tolerance indices through principal component analysis. All the indices were positively correlated with each other with the exception of drought susceptibility index, which was negatively correlated with all other indices used in the study. The first PC that accounted for 73.01 % of variation, and indices such as yield (non-stress), yield (stress), geometric mean (GM), harmonic mean (HM), drought resistance index(DRI), coefficient of drought resistance (CDR), drought tolerance index (DTI) and relative drought index (RDI) were related to tolerance and percent reduction and DSI were related to susceptibility. The genotypes with higher component scores of PC1 viz., WB-1634 (1.97), WB-341 (1.371), WB-185 (1.268) and WB-451 (1.253) are also tolerant to drought. The Biplot of PC1 and PC2 also revealed WB-1634 as tolerant, whereas genotypes WB-6, WB-1587 and SR-1 as susceptible to drought.

Keywords

• Common bean
• drought stress
• PCA
• tolerance indices