Table II. Summary of changes in xanthophyll pigment composition and associated changes in photosynthetic parameters in rapid light-response curves in detached, sun-exposed avocado shade leaves in experiment 4

Values are means ± se (n = 4).

Detached Leaves; Experiment 4 (1,200 μmol photons m−2 s−1)Shade Leaf Predawn60 min of Sunlight90 min of SunlightRecovered 22 h in the Shade
Pigments (mmol mol−1 chlorophyll) and deepoxidation states
 [Lx]30.4 ± 2.312.4 ± 0.610.5 ± 0.911.6 ± 0.6
 [L]104.7 ± 1.1133.9 ± 0.8130.9 ± 2.3130.1 ± 1.5
DESLx00.680.710.69
 [V]31.8 ± 0.210.4 ± 0.29.8 ± 0.216.3 ± 1.5
 [A]0.2 ± 0.22.5 ± 0.33 0.0 ± 0.17.9 ± 0.9
 [Z]2.4 ± 0.429.1 ± 0.528.4 ± 1.617.5 ± 1.5
DESV0.08 ± 00.76 ± 00.76 ± 0.010.61 ± 0.04
Photosynthetic parameters from initial slope and saturation at PFD (μmol photons m−2 s−1)
 1 − qP (94)0.78 ± 0.010.91 ± 0.010.95 ± 0.020.88 ± 0.01
 1 − qP (467)0.92 ± 0.010.94 ± 0.010.98 ± 0.030.85 ± 0.03
ETR (94)5.3 ± 0.20.9 ± 0.20.3 ± 0.21.0 ± 0.1
ETR (467)9.4 ± 1.21.7 ± 0.50.3 ± 0.33.0 ± 0.3
NPQ (94)0.74 ± 0.022.59 ± 0.083.83 ± 0.233.45 ± 0.47
NPQ (467)1.38 ± 0.033.13 ± 0.084.48 ± 0.264.22 ± 0.47
Photosynthetic parameters from independent measurements
Fv/Fm0.79 ± 00.18 ± 00.14 ± 0.030.18 ± 0.06
 PSII/PSI (arbitrary ratio)0.56 ± 0.010.22 ± 00.28 ± 0.030.32 ± 0.06