Fig. 6.

Modulated chlorophyll fluorescence during two consecutive hydration/desiccation cycles of Rhytidium rugosum interspaced by a 60 min illumination period (PPFD of 10,000 μmol⁻² s⁻¹) of the dry moss. (A) Thalli exposed for 4 days to full sunshine during a high-pressure period in early October and dried. (B) Thalli obtained as in A hydrated in near-darkness for 2 days in the laboratory and then dried in darkness. Strong light pulses (1 s) were given every 500 s. For explanation, see text.