[CO2-fixation metabolism in the halophytic species Mesembryanthemum crystallinum grown under different environmental conditions].

The correlation of CO2-fixation metabolism to various environmental conditions such as NaCl content of culture medium, air humidity and light intensity was investigated in the halophytic species Mesembryanthemum crystallinum. The data obtained demonstrate that a change in photosynthesis from C3-pathway to crassulacean acid metabolism (CAM) is observed not only in NaCl treated plants as reported earlier but also in control plants grown in non-saline medium when environmental conditions (high light intensity, low air humidity) cause a water deficit in the leaves. It is suggested that water stress plays an important role in regulation between C3- and CAM-pathway of photosynthesis in Mesembryanthemum crystallinum.