Genetic diversity among accessions of Solanum aethiopicum L. groups based on morpho-agronomic traits

Abstract

Solanum aethiopicum L. is indigenous to Africa and constitutes an important vegetable. Morpho-agronomic traits were used to study diversity among 44 accessions of S. aethiopicum groups to identify traits of high discriminatory ability and donor parents with specific or multiple traits for introgression and utilization in breeding programmes. Field experiments were conducted from 2008 to 2010. The principal component (PC) analysis of morpho-agronomic data indicated high discriminatory ability for fruit calyx length, fruit length and leaf length. On PC1, fruit length showed positive and significant correlation coefficients with leaf length, fruit calyx length and width. An independent association was recorded among fruit width, fruits per infructescence and seed yield (t/ha). Ordination (biplot) and grouping (dendrogram) revealed genetic variation and relatedness, phenotypic plasticity and geographical heterogeneity among the accessions within and among the clusters. Members of cluster 1 (group ‘c’) are a promising donor parent for multiple traits (earliness and fruit length), and members of group ‘b’ are superior for fruits per plant, fruits per infructescence and fruit infructescence per plant. Hybridization among distant clusters would provide an opportunity for bringing together gene constellations of diverse background. Earliness and fruit length were highly variable among the S. aethiopicum groups. The results are important for the breeding and selection of this crop.