Fig. 3.

Malate (a) and citrate (b) secreted from roots of E. grandis × E. urophylla G9 and E. urophylla W4 after 24 h of exposure to aluminium in the absence or presence of the anion channel inhibitor phenylglyoxyl (PG) or the protein synthesis inhibitor cycloheximide (CHM). Bars represent means ± standard errors (n = 3). Different letters above the bars indicate a significant difference at P < 0.05. CK, non-Al-treated control