Chl a fluorescence parameters of C. aculeata and D. muscorum samples representing control and experimental groups in relation to time after hydration (dot = mean, box = SE, whisker = 95% confidence interval; n = 6–11): a, b QY_max – maximum PSII quantum yield in a dark-adapted sample; c, d QY – the effective PSII quantum measured in light; e, f NPQ – the non-photochemical fluorescence quenching in light state. The different letters above the bars indicate significant differences (p < 0.05). Lowercase letters indicate a significant interaction, capital letters indicate the significant effect of time. The asterisks indicate a significant effect of the experimental group. For details see Suppl. material 1: table S2.