Genetic diversity analysis of pigeonpea [Cajanus cajan (L.) Millsp.] Under cold stress conditions

In this study, one forty five pigeonpea genotypes were assessed for cold tolerant associated traits. For evaluation of these traits, principal component and correlation analyses were applied to select desirable parents that can be further exploited in future breeding programmes. Correlation analysis revealed pods per plant, biomass, 100-seed weight, harvest index and osmolarity had positive and significant associations, while the membrane injury index had a significant negative correlation with yield at cold stress condition. The significant association among these yield contributing traits suggested that these traits are important for direct selection of cold tolerant high yielding genotypes. Principal component analysis (PCA) revealed that 99% of the total diversity was explained on the basis of the first three principal components. Cluster analysis classified 145 pigeonpea genotypes into four divergent groups. The members of first three clusters may be combined in future breeding programmes to obtain varieties / hybrids that can perform well under cold stress conditions. The results showed that the genotypes having a wide genetic diversity can be utilized for future breeding programme to obtain cold tolerant pigeonpea varieties / hybrids.