Fig. 10.

Al³⁺ binding of cell-wall material isolated from 1 cm root tips of Al-sensitive common bean genotype (VAX 1). Plants were pre-treated without or with 150 g l⁻¹ PEG for 24 h in a simplified solution (pH 4.5) containing 5 mM CaCl₂, 1 mM KCl, and 8 μM H₃BO₃. Then, 30 root tips (1 cm) were harvested and cell-wall material was isolated according to Method A or Method B, described in the Materials and methods. Then the isolated fine cell-wall powder was treated with 1 ml 300 μM Al for 30 min, pH 4.3. Bars represent means ±SD, n=4. Means with the same small letter and capital letter are not significantly different at P <0.05 (t test) for the comparison of the method of CW isolation within PEG pre-treatments and comparison of PEG pre-treatments within the method of CW isolation, respectively.