Figure 6.

Pi deficiency-induced Fe, ROS, and callose deposition in root apex. (A,B) Fe staining by Perls (A) and Perls/DAB (B). Four-day-old plants grown on +Pi or −Pi medium for three days. The experiments were repeated three times with similar results. Bar = 50 um. (C) NBT staining of superoxide (O₂^–) anion in WT and mutant roots. Four-day-old seedlings were transferred to +Pi or −Pi medium for three days; the roots were stained with 1 mM NBT solution for 60 min and photographed under microscopy. Bar = 50 μm. (D) Aniline blue staining of callose in primary roots after transfer of four-day-old plants to +Pi or −Pi medium for three days. Bar = 50 μm.