Figure 6. Effect of S-deprivation and re-supply on expression of OsNRT2.1, OsNAR2.1, OsIPS1 and OsSULTR1;1 in rice roots.

Rice seedlings were grown hydroponically in a growth cabinet. Sulfur treatments were as described in Fig. 3. C: continuous complete nutrient supply; −S: starved of S; +S: resupplied with SO₄ ²⁻ for 3 h. Total RNA was extracted from roots and qPCR reactions were performed in triplicate for each RNA sample. The mRNA of OsActin was used as the reference. A Student’s t-test was calculated at the probability of either 5% (*, p<0.05) or (**, P<0.01).