Figure 10. Photoinhibition of PSII in Col-0, Ws-4 and Ler-0 accessions.

Leaves detached from plants grown hydroponically at an irradiance of 120 µmol photons m⁻² s⁻¹ (GL) were exposed for 3 h to GL or high light (HL = 950 µmol photons m⁻² s⁻¹) treatments in the presence or absence of lincomycin (LN). (A) The F _v /F _m parameter was determined in leaves after 5 min dark adaptation. The levels of F _v /F _m were calculated relative to a value of 0.82, obtained in 16 h dark-adapted Col-0 leaves, and plotted as means ±SD (n = 3). (B) Thylakoid membranes were isolated from the treated leaves and subjected to western blotting with anti-D1 and with anti-Lhcb2 (as loading control) (0.25 µg Chl/lane). (C) Transmission electron micrographs of chloroplast ultrastructure from plants exposed to 3 h HL. Scale bar: 1 µm.