Figure 10.

Total dry weights (A) and free nitrate and ammonium pools (B) in leaves and roots of plants grown with and without nitrogen. Two-week-old plants grown on nitrogen were transferred to growth media with (+N) and without (−N) nitrogen for 5 d. A, Dry weight of tissues used to quantitate nitrate and ammonium levels in B (complete tissues from 20 seedlings were used for A and B). B, Levels of free nitrate and ammonium as indicated in leaves and roots of +N and −N plants. Results are an average of three biological replicates. Error bars indicate se.