Fig. 7.

Effect of WRKY21 and WRKY108 mutations on phosphate (Pi) homeostasis in rice (Oryza sativa). (a) Cellular Pi concentration analysis of wrky21 (line wrky21‐2), wrky108 (line wrky108‐17), wrky21 wrky108 mutants and wild‐type plants. Four‐leaf‐old seedlings were grown under half‐strength Kimura B nutrient solution supplied with 1 mM Pi, 300 μM Pi, 90 μM Pi or 1 μM Pi until the seventh leaf blades were fully expanded. Pi concentration was measured in shoot (left) and root (right). (b) RT‐qPCR analysis of the effect of wrky21 wrky108 double mutants on the expression of four PHT1 genes. Plant roots were collected for RNA extraction and RT‐qPCR analysis. The rice housekeeping gene OsActin1 (LOC_Os03g50885) was used as an internal control. Values represent means ± SD of four biological replicates. Data significantly different from that in corresponding controls are indicated (*, P < 0.05; Student’s t‐test). FW, fresh weight.