Figure 7.

The Al-induced depolymerization of cortical MTs in the root apex TZ and MT-regulated Al-induced root growth inhibition is mediated by JA signaling. A, The cortical MTs of the root apex TZ cells of 6-d-old GFP-MAP4 and coi1-2GFP-MAP4 seedlings upon treatment with 0 and 10 µm AlCl₃, 100 nm MeJA, or 100 nm oryzalin for 6 h. Bar = 100 µm. B, Root growth of wild-type seedlings and coi1-2 mutant in response to Al stress and oryzalin treatment. The wild-type seedlings and coi1-2 mutant were exposed to 0 and 10 µm AlCl₃ in the presence of 0 to 70 nm oryzalin for 7 d. * and ** indicate a significant difference between Al treatment alone and Al plus oryzalin treatment in either wild-type or coi1-2 mutant seedlings at P < 0.05 and P < 0.01, respectively. Values represent means ± sd (n = 30).