Abstract: This article mainly focuses on the degradation course of enzymatic reaction of cell coat system including cell wall and cytoplasma membrane of the Arabidopsis thaliana leaves under acid conditions. Under light microscopic observation, the cell walls of the leaves of A. thaliana which is under the acid condition are intact and arranged in order at first, thereafter the cell wall begins to degrade partly, and the cells tend to disordered state gradually, afterwards the cell walls are totally degraded. Protoplasts isolated by enzyme digestion totally enter the free state, and accompanied by the degradation of the cytoplasma membrane of the free protoplasts, having overflowed, the organelle surround the nucleus, and thus a new protoplast is reconstituted. We further observed the change of pH in the cell in this course. The result indicated that the cell tended to the pH value decrease during the course of the acid enzymatic degradation, and the pH of the protoplast reconstituted from the organelle came back to its normal level. In conclusion, the acid environment had an important effect on the degradation of the cell coat system of A. thaliana leaves.

Key words: Arabidopsis thaliana, leaves, cell coat, acid degradation