RELATION BETWEEN CALCIUM CONTENT AND RESI STANCE TO ENZYMATIC DIGESTION OF THE SKIN DURING GRAPE RIPENING

The evolution of calcium during grape berry development and ripening i s irregular. The changes in calcium content of cell wall will have imp ortant consequences, mainly on the skin which is responsible for the b erry reaction during attack by pathogenic fungus Like Botrytis cinerea . Our study about the evolution of the susceptibility to enzymatic dig estion of berry skin from different cultivars during ripening reveals that the more important the cell wall calcium content, the less suscep tible is the skin. Precisely, cell wall cohesion of the skin tissue re sults in the chelation state of the pectic substances.