Figure 4.

Iron Deficiency Response of pye-1 Mutants.

(A) Iron reductase activity of wild-type (WT) and pye-1 plants germinated and grown on +Fe media for 5 d and then shifted to –Fe media for 3 d (±se). The ferrozine assay was performed, in quadruplicate, on 10 pooled plant roots. Significant differences from the wild type are indicated by *P < 0.05.

(B) Rhizosphere acidification of 7-d-old wild-type, pye-1, and bts-1 plants exposed to iron-deficient media for 3 d. Plants were then transferred to agar plates containing Bromocresol Purple for 1 d. Acidification is indicated by yellow color around the roots.

(C) Perl-stained maturation zone of 2-week-old plants germinated and grown on iron-sufficient media.

(D) to (G) Fe (D), Zn (E), Mn (F), and Co (G) content of wild-type and pye-1 roots and shoots germinated and grown on +Fe (+) media for 5 d and then shifted to –Fe (–) media and grown for 3 d (±se). Gray indicates the wild type, and white indicates pye-1. Significant differences from the wild type are indicated by *P < 0.05.

Bars = 3 mm in (B) and 50 μm in (C).