Fig. 6.

OsNRT2.4 expression pattern in response to different nitrate treatment in the root and shoot of wild-type (WT) and osnrt2.4 knockdown lines (r1 and r2). Rice seedlings were grown in a hydroponic system. Thirteen-day-old seedlings were transferred into nutrient solution without nitrogen for 4 days (starvation) or with 0.1mM N-NO₃⁻ for 4 days (low nitrogen). Total RNA was isolated from roots at 04.00h (04) (light start). (a) OsNRT2.4 relative expression in root and (b) OsNRT2.4 relative expression in shoot. The expression levels were normalized to the expression of the OsUBC and OseEF-1α reference genes. The experiment was performed using four biological replicates for each genotype. Bars indicate the standard error of the mean (n =16). Asterisk (*) indicates statistically significant differences between WT and two mutant lines by the Dunnett’s test (p<0.05)