Fig. 7.

Root average diameter (A) and volume (B) after long-term treatment with Mn plus Al or Mn only. Rice seedlings (11 d old) were grown in nutrient solution containing 6·7, 200, 500 or 1000 µm Mn without or with 200 µm Al for 3 weeks. Values are mean ± s.e. (n = 12 replicates). Asterisks above columns indicate statistically significant differences between control and Al treatment (P < 0·05; independent samples t-test).