Genetic diversity of Bambara groundnut genotypes (Vigna subterranea [L.] Verdc.) revealed by SSR markers

Abstract

Bambara groundnut is an under-utilized legume of African origin with the potential to alleviating food security issues in Africa. There is limited research output on genetic diversity, selection and breeding of the crop, especially using genomic tools. Landraces were mostly being characterized using morphological markers whose expression is heavily influenced by environmental factors. Molecular markers provide a better choice for genetic diversity studies, because crop species are not affected by environmental factors. SSR markers have been found to be most convenient for genetic analysis, especially that they are multiallelic, co-dominant and evenly dispersed throughout the genome. The objective of the study was to genotype 50 Bambara groundnut lines from single plant selection that were obtained from seven geographical regions across Africa using five polymorphic SSR markers. The analyses detected a total of 53 alleles, with a mean of 10.6 alleles per locus, while genetic distance measured by polymorphic information content ranged from 0.0 to 3.8, with a mean of 0.76. The neighbor-joining analysis generated seven major genetic groups, clustered irrespective of geographic origin.