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

Figure 4

Discriminant analysis of principal components (DAPC). (a) DAPC depicting a clear differentiation between biparental RILs and the other three populations but precisely separated multiparental RILs from breeding lines while accessions remained together with the breeding lines. A clear separation of the population into three gene pools is depicted by DAPC. (b) DAPC clustering showing the extent of structure within each genetic population: breeding lines being the most structured, having multiple black blocks, and biparental RILs being the least structured, having just one black block; legend at the bottom of (b) indicates the relative sizes of the blocks. (c) Bayesian information criteria (BIC) versus the number of clusters, depicting appropriate number of clusters used in determining extent of structure within each genetic population. The optimal number of clusters corresponds to the lowest point of the curve where BIC is at its lowest value.

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