CO2 fixation in leaves of a CAM plant without lower epidermis and the effect of CO2 on their deacidification

The effects of peeling the epidermis off Bryophyllum daigremontianumleaves on CO₂ uptake in light and darkness were investigated.Light-induced CO₂ uptake in the daytime was markedly enhancedin the peeled leaves, but dark fixation of CO₂ carried out atmidnight was not. The difference in promotion of CO₂ uptakein light and darkness was due to stomatal closing in the dayand opening at night. Also, deacidification was strikingly inhibitedby CO₂ in peeled leaves. (Received February 3, 1977; )