Plots of the first three principal components derived from a principal component analysis (PCA) of 263 alfalfa genotypes using SNP markers generated on an Infinium array, with (a) PC1 vs. PC2 and (b) PC2 vs. PC3.

<p>(C1: diploid subsp. <i>falcata</i>, C2: diploid subsp. <i>caerulea</i>, C3: miscellaneous tetraploid alfalfa, C4: dormant and semi-dormant tetraploid subsp. <i>sativa</i>, and C5: semi-dormant and non-dormant tetraploid subsp. <i>sativa</i>)