A Mid-Density Single-Nucleotide Polymorphism Panel for Molecular Applications in Cowpea (Vigna unguiculata (L.) Walp)

Figure 3

Population structure of the 330 cowpea genotypes constituted from a sample of lines coming from four different genetic backgrounds. (a) Plot of versus Delta showing the most probable number of subgroupings (). (b) STRUCTURE bar plots depicting two groups before excluding bparental recombinant inbred lines (RILs); Supplementary Figure 2 shows the exposition of additional subgrouping in the remaining data set after dropping biparental RILs. (c) Principal component analysis (PCA) displaying the scattering of genotypes along X (PC1) and Y(PC2) axes. PCA revealed a close scattering of biparental RILs, with the accessions and breeding lines together being the most scattered, while multiparental RILs are clearly visible as a moderately clustered subset within the bigger group.

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