Fig. 3From: Dynamic light caused less photosynthetic suppression, rather than more, under nitrogen deficit conditions than under sufficient nitrogen supply conditions in soybeanPhotosynthetic gas exchange under fluctuating light conditions. The time course of the net photosynthetic rate (Pn; a, b) under fluctuating light in the leaves of high nitrogen (HN; black) and low nitrogen (LN; grey) supply plants. The bar above the plot (a) shows the high (1600 μmol m− 2 s− 1; HL; white bar) and LL (100 μmol m− 2 s− 1; LL; grey bar) periods. The leaves were adapted under HL (1600 μmol m− 2 s− 1) for 20–40 min until the Pn stabilized, after which the leaves were exposed to fluctuating light such that the light intensity alternated between high (1600 μmol m− 2 s− 1) and low (100 μmol m− 2 s− 1) conditions every 120 s. The original Pn is shown in plot (a). In plot (b), the Pn under steady HL was taken as 100%, and the Pn under changing light conditions was calculated as a percentage of the Pn under steady HL. (b) The maximum Pn during the HL period (Pnmax) in HN- and LN-supplied plants; the Pn under steady HL was taken as 100%, and the Pnmax was calculated as a percentage of the Pn under steady HL. (c) The integrated Pn during fluctuating light in HN- and LN-supplied plants. Means ± SD, n = 6. The asterisks indicate significant differences at P < 0.05 between HN and LN leaves (T-test)Back to article page