Deacidification of the leaves ofBryophyllum Calycinumunder anaerobiosis: Abnormal efflux of malate into the cytoplasm

摘要

We investigated the effect of anaerobiosis on deacidification of the leaf of a CAM plant,Bryophyllum calycinum. When leaf segments were placed in a stream of N2in the dark, deacidification was suppressed remarkably. A similar effect also was observed when segments were placed in the light, provided that these segments were infiltrated with DCMU before use. Conversion of chlorophylls into phaeophytins, wilting of the leaf segment, and a loss of the photosynthetic CO2-fixation activity were observed simultaneously during the incubation period.We confirmed that these phenomena are caused by damage to cells caused by the enormous amount of acids stored in the vacuole that are extruded into the cytoplasm.