Diversity among Bambara groundnut (Vigna subterranea L. Verdc) accessions using agro-morphological traits and diversity array technologies sequence low density markers in Malawi

Abstract

Bambara groundnut (Vigna subterranea (L.) Verdc) is a neglected and underutilized crop that plays a big role in improving livelihoods of smallholder farmers in Sub-Saharan Africa. Despite its importance, there is limited availability of commercially improved cultivars to smallholder farmers in Malawi. This study characterized selected Bambara groundnuts accessions for agro-morphological traits for germplasm discrimination. It also identified genetic variation using Single Nucleotide Polymorphism (SNP) markers through Diversity Array Technologies Sequence Low Density (DArTseqLD) that could be used to produce improved seed for crop improvement. Forty Bambara groundnuts accessions were evaluated at the Crops and Soil Sciences Department’s farm of Lilongwe University of Agriculture and Natural Resources, Bunda College, Malawi. From the 40 accessions, 188 unique seed samples were selected for genotyping using DArTseqLD SNP markers. Data on agro-morphological traits were collected following the Bambara groundnut descriptor guidelines and multivariate analysis were performed. Principal Component Analysis revealed a total variation of 53%. The study generated 1048 DArTseqLD SNP markers. Analysis of molecular variance (AMOVA) identified 84% and 13% of genetic variation among and within the Bambara groundnut accessions respectively, whereas 3% genetic variation was observed among the total populations. Cluster analysis based on genotypic data grouped the 188 samples into 10 clusters. Based on phenotypic and genotypic data, it can be concluded that there is a significant degree of variation and genetic diversity in the accessions evaluated that can be used in crop improvement program as well as being directly used by farmers in seed production.