Yeasts play a significant role in nutrition, medicine, and bio- control of plant pathogens. Certain yeasts act as antagonists in postharvest infections on fruits such as apples and citrus. However, fungi cause most plant disease, accounting for perhaps 70% of allmajor crop diseas.Apart from the effects of high temperature and relative humidity, fungi produce pectic enzymes that break down apple pectin to expose the nutrients of the cells to the fungi