Erys is a genus of fungi belonging to the family Erysiphaceae. These fungi are commonly known as powdery mildews, which are characterized by their white, powdery appearance on the surfaces of plants. They primarily affect a wide range of host plants, including crops and ornamental species, leading to reduced growth and yield. The life cycle of Erys involves both asexual and sexual reproduction. Asexual spores, called conidia, are produced on the surface of infected plants and can spread easily through wind and water. Effective management of Erys infections often includes cultural practices, resistant plant varieties, and fungicides to minimize their impact on agriculture.