Figure 7.

Effect of 10-d intermittent Al treatment on the concentrations of P, Ca, Mg, and Al in cv Shanxi (A, leaves; B, roots) and cv Jiangxi (C, leaves; D, roots). The intermittent Al treatment was conducted as follows: The plants after 10-d culture in nutrient solution were exposed to Al treatment solution (50 μm AlCl₃ in 0.5 mm CaCl₂ at pH 4.5) for 1 d and nutrient solution on alternative days for 10 d (black bars). For the treatment lacking Al, they were transferred to 0.5 mm CaCl₂ solution at pH 4.5 for 1 d and nutrient solution on alternative days for 10 d (white bars). Values shown are means ± sd (n = 3).