Expression of root Pht1 transporter genes in response to increasing soil P supply.

<p>Roots were sampled at the 8-leaf stage for pot plants (open symbols) and at the flowering stage for field plants (closed symbols). Gene relative expression level was measured by real-time quantitative RT-PCR. UBQ2 was used as the internal control. For each gene, the lowest expression level was set equal to 1.0. Each symbol represents the mean (± SE) of three replicates for the pot experiment and four replicates for the field experiment, respectively.