Fig. 2. Responses of the relative values of actual PSII efficiency (ΔF/Fm') and potential quantum efficiency of PSII (Fv/Fm value of the same leaves before illumination being 100%) in Eulophia dentata (A), Bletilla formosana (B), and Saccharum spontaneum (C). These ChlF parameters were obtained at artificial illumination of 60 min (L60) and a subsequent dark recovery for 2 min (D2), 10 min (D10), 20 min (D20), and 30 min (D30) periods under 50, 100, 300, 500, 800, 1,000; 1,500; and 2,000 μmol m–2 s–1 PPFD at 25°C. Each point represents the mean of five leaves, and data are means ± standard errors. Different letters indicate significant differences in Tukey's HSD analyses at eight illuminations (P<0.05).
