Figure 3. Cumulative ¹⁵N-NO₃⁻ uptake in wild-type (WT) and osnar2.1 knockdown lines (r1 and r2).

Rice seedlings were grown for 1 wk in hydroponic medium containing 10 mM NO₃⁻ and then transferred for a further week to media containing 0–10 mM ¹⁵N-NO₃⁻. (a, b) Cumulative ¹⁵N-NO₃⁻ uptake in the shoots (a) and roots (b). Values are means ± SE (n = 6). *P < 0.05 (ANOVA) comparing WT plants and two mutant lines in the same treatment.