Figure 9.

Analysis of Pi starvation-induced root APase activity in 8-d-old Arabidopsis seedlings of the wild type, miRNA399 OX, and pho2 grown under P⁺ and P⁻ conditions. A, Histochemical staining of APase activity on the root surface of the seedlings using BCIP as a substrate. B, Root surface-associated APase activity as determined with BCIP as the substrate. C, Root intracellular APase activity as determined with BCIP as the substrate. Values in B and C represent means with se of three replicates. Asterisks indicate a significant difference (P < 0.05) from the wild type according to Student’s t-test.