Principal component analysis of early generation sorghum lines for yield-contributing traits and resistance to midge

Abstract

Sorghum (Sorghum bicolor L. Moench) is a staple food crop in Niger. Its production is constrained by sorghum midge (Stenodiplosis sorghicola Coquillett 1898) and by the use of low-yielding, local sorghum varieties. To improve sorghum productivity, farmers need high-yielding and midge-resistant sorghum cultivars. The objective of this research is to evaluate genetic diversity among sorghum inbred lines for yield, yield-contributing traits, and resistance to midge. Two-hundred and eighty-two lines (280 recombinant inbred lines plus two checks) were evaluated at two experimental sites in Niger. An alpha (0.1) lattice design with two replications was used to conduct the trial. Principal component analysis was used to determine the relationship between grain yield and resistance to midge. The first three principal components (PC) accounted for 56.22% of the total genotypic variation. Based on the similarity of traits within and between members of clusters, genotypes were divided into 18 clusters. Genetic variability was present for the traits under study in the tested germplasm. Hybridization of midge-resistant genotypes from different clusters should be able to yield new genotypes combining high yield and other desirable yield-contributing traits.