Grape management techniques: what is grape downy mildew?

What is grape downy mildew? What harm does downy mildew do to grapes? How to prevent and cure grape downy mildew? Netizens are also asked to help guide the field network to summarize the harm and control methods of grape downy mildew, which are listed below for netizens' reference. Downy mildew harm to grapes: grape downy mildew is mainly harmful to leaves, but also to young parts such as new shoots, buds and young fruits. Irregular light yellow translucent oily spots appeared on the front of the leaf, which gradually expanded to yellowish green, and the edge boundary was not obvious. most of the small spots were connected into an irregular or polygonal large disease spot, and a yellow-white frost-like mildew layer was produced on the back of the leaf. The disease spot became light brown in the later stage. The tender shoots of grapes also showed oil-immersed disease spots, with yellow-white mildew on the surface, but less than leaves. In the early stage of young fruit infection, the disease part became light green, and in the later stage, the disease spot became dark brown and sunken, resulting in a layer of frost-like white mold, and the fruit hardened and shrunk. Prevention and control methods of grape downy mildew: 1. In the growing season and autumn pruning, diseased branches, leaves and fruits should be thoroughly removed and taken out of the field for centralized burning. 2. Cut off the superfluous branches and leaves of the auxiliary tip in time to create good ventilation and light transmission conditions. 3. The grape can be protected by spraying a small amount of Bordeaux solution every 10 days before the disease. After the onset of the disease, use 50% gram carbendan 500x solution, or 65% Dysen zinc 500x solution, or 25% metalaxyl 800-1000 times solution spray prevention and control. Click to get more grape planting techniques click to get more fruit planting techniques