Fig. 8

Principle component analysis (PCA) scores plot (a) and the corresponding loading plot (b) of root metabolome variation among the two cultivars based upon four biological replicates. PC1: the first principal component; PC2: the second principal component. The PCA scores plot distinguishes the metabolic profiles of the two cultivars under +Pi and − Pi conditions. The main metabolites contributing to the PC1 and PC2 are labeled