Fig. 2

Expression of root high-affinity (NtNrt2.1; A, B) and low-affinity (NtNrt1.1; C, D) nitrate transporter genes in response to calcium inhibitor and nitrate treatments. Three-week-old plants were incubated for 1 h in H₂O, 5 mM LaCl₃, 10 μM U73122 or 10 μM U73343, followed by 1 h in 5 mM KNO₃ or 5 mM KCl. The significant differences (P < 0.05) for multiple comparisons are shown with different letters separately for each panel, whereas no letter or same letters indicate insignificant variation