Leaf Pyr content of dark adapted and 3 min illuminated WT and T27 leaves. Leaves were dark adapted for 2 h prior to illumination for 3 min at 1,300 µmol quanta m⁻²s⁻¹. Values are the means ± se, n = 8 except for dark adapted T27 where n = 6. Asterisks indicate statistically significant differences by two-tailed Student’s t test: ^*P < 0.05; ^**P < 0.01; ^****P < 0.0001.