Figure 9.

Effect of Al on [³H]IAA distribution relative to entire IAA uptake into the apex of primary roots of the maize cv ATP-Y (Al-resistant) and cv Lixis (Al-sensitive). Application of 90 μm monomeric Al, 10 μm NPA, or 10 μm TIBA in nutrient solution, pH 4.3, in 0.6% (w/v) agarose gel to the DTZ for 30 min. Control roots were treated only with nutrient solution in agarose blocks, pH 4.3. [³H]IAA (0.1 μm in 1.2% [w/v] agarose blocks containing nutrient solution) was applied to the MZ for 30 min. Values are means of five independent replicates ± sd. The results shown are representative of three independent experiments. Different letters indicate significant differences at P < 0.05 (Tukey test).