Figure 2.

Ammonium (A,B), amino acids (C,D), and protein content (E,F), of shoots (A,C,E) and roots (B,D,F) of plants grown under different conditions of pH (5.7 or 6.7), N source (${\text{NO}}_3^{-}$ or ${\text{NH}}_4^{+}$), and concentration (2 or 10 mM). Statistical analysis was described in Figure 1. Columns represent mean ± se (n = 3). Each sample is a pool of three plants.