Multivariate Analysis of Yield and Yield Contributing Traits in Pigeonpea (Cajanus cajan) Introgression Lines Derived from Wild Relatives

Abstract

Pigeonpea (Cajanus cajan (L.) Millsp.) has limited genetic diversity, necessitating the use of wild relatives for crop improvement. This study evaluated phenotypic variability, trait associations, and principal component structure in four BC₂F₂ populations derived from interspecific crosses involving cultivated genotypes and wild species. Parental lines showed clear divergence, with cultivated types exhibiting early flowering (112–118 days), early maturity (168–172 days), and higher yield, while wild relatives contributed greater plant height (175–185 cm) and branching (up to 26 secondary branches). The BC₂F₂ populations exhibited substantial variability, indicating effective introgression. Correlation analysis showed grain yield had a positive association with secondary branches (r = 0.27) and test weight (r ≈ 0.04). Path analysis revealed the highest positive direct effect from secondary branches (0.16), followed by test weight (0.04). Principal component analysis indicated that the first three components explained 73–76% of total variation, with PC1 (35–40%) associated with yield traits and PC2 (20–25%) with phenology. These results highlight the potential of wild introgression populations for selection and development of high-yielding pigeonpea cultivars.