Figure 6.

Effects of foliar Fe supply on the occurrence of heavy metal-induced physiological and morphological responses in Col-0 and irt1. Seven-day-old seedlings grown on one-half-strength MS medium were transferred to one-half-strength MS medium containing elevated concentrations of the indicated heavy metals. Leaves were supplied or not with 250 µm Fe(III) citrate. A, Appearance of plants. B, Chlorophyll concentration. C, Primary root length. D, Average lateral root (LR) length. E, Lateral root density. F, FCR activity. Bars represent means ± sd. Different letters indicate statistically significant differences among means for each heavy metal (P < 0.05, Tukey’s test). FW, Fresh weight.