Fig. 7

Zinc and cadmium concentration in the shoots and roots of tobacco plants after 3-day exposure to Cd. 5.5-week old plants grown in the quarter-strength Knop’s medium were exposed to the control medium containing 1 μM Zn with (1 μM Cd) or without Cd for 3 days. Zn concentration in the shoots (a), and roots (b). Cd concentrations in the shoots (d) and roots (e). The translocation factor (TF) was determined as the ratio of shoot/root concentrations of Zn (c), and Cd (f). Values correspond to means ±SD (n = 10). Significance of differences between all values were evaluated by Student’s t-test (P ≤ 0.05), and it has been determined that each pair of values is significantly different if the SD bars do not overlap. Significance has not been marked above the bars with the letters or arrows to keep the clarity of the graph