Principal component analysis (PCA) of metabolic profiles in the leaves of W and M under control and 45 mmol.L^-1 neutral-salt and alkali-salt stress (four biological replicates).

<p>W: wild soybean, M: cultivated soybean; CK: control treatment, NS: neutral-salt stress, AS: alkali-salt stress; PC1, the first principal component; PC2, the second principal component.