Fig. 4.
The effect of light orientation and dark chilling on the light-response curves for photosynthesis in whole P. dilatatum leaves. Plants were either maintained at optimal growth temperatures (black circles) or subjected to dark chilling for either one (light grey inverted triangles) or two (dark grey squares) nights. Light intensity was increased in a stepwise manner from 0 to 1500 μmol m−2 s−1 with orientation to either the adaxial (A) or the abaxial (B) leaf surface. Data are the mean values±SE of nine plants per treatment.