Powdery Mildew A Disease of Grapes And The Fungicides Mode of Action: A Review

Powdery mildew caused by Uncinula necator (Schw.) Burr. is one of the widespread fungal diseases of grapes that have caused economic losses through poor fruit set and low yield substantially. To decrease the inoculum potential, a disease management program must be undertaken early in the season which is imperative to reduce late-season disease problems. Because, without early control of the infection of powdery mildew, often lead to severe problem in the late season. Elemental sulfur was the foremost antifungal utilized for the control of powdery mildew which is still in use as an effective and cheap fungicide for vineyards. Sterolbiosynthesis inhibitors (SI), also called SI fungicides, are the latest products to control powdery mildew effectively. For efficient use of fungicides with no or less resistance to the pathogen, it is appropriate to spray fungicides having different mechanisms of action which are specific in function, and for more efficacy, use a mixture of such fungicides that have no harmful impact on plant growth and environment. So, for effective control of powdery mildew, a protective spray of fungicide before bloom and a subsequent spray of systemic fungicides at the time of berry formation ensure healthy and higher grapes yield. This paper reviewed the powdery mildew infection in grapevines and its effect on yield losses with details of fungicides’ mechanism of action and newly developed fungicides having broad spectrum activities.