Fig. 3From: Leaves play a central role in the adaptation of nitrogen and sulfur metabolism to ammonium nutrition in oilseed rape (Brassica napus)Nitrogen source effect on ammonium assimilatory enzyme activities in roots and leaves of B. napus. GS (a), NADH-GOGAT (b), NAD(H)-GDH (c) and NADP(H)-GDH (d). Plants were hydroponically cultured with 0.5 and 1 mM nitrate or ammonium. Values represent mean ± SE (n = 4). Different letters indicate statistical differences between treatments (ANOVA analysis with Duncan’s test, P < 0.05). Asterisk (*) indicates significant nitrogen source effect within each nitrogen concentration (t-test, P < 0.05)Back to article page