High temperature and humidity powdery mildew is easy to epidemic and how to control grape powdery mildew

The muggy weather in summer provides conditions for the breeding of grape powdery mildew. Generally, the peak period of the disease is from July to August, and the disease is the fastest, and the epidemic spreads with high temperature and humidity. How to do a good job in the prevention and control of this stage is related to the overall quality and yield of grapes. It is suggested that the majority of grape growers should be strictly monitored and dealt with in time once diseases are found.

Grape powdery mildew

Powdery mildew is most likely to affect all the green parts of the young tissue of grape plants, generally producing irregular chlorosis or small yellow patches on grape leaves, and a layer of white powder can be seen on both sides of the disease spot. The infection of powdery mildew gradually caused the leaves to curl and wither and even fall off, which made the fruit stalks brittle and the growth of branches blocked. Grape powdery mildew is at its peak from mid-June to late July, and grape cultivated in protected areas is most prone to powdery mildew and epidemic. The main reasons are drought, overdense cultivation, excessive application of nitrogen fertilizer, untimely pruning of branches, and so on.

Scientific prevention and control of grape powdery mildew is very important for grape prenatal. It is suggested that the vineyard should be thoroughly cleaned up, the environment needed for the spread of powdery mildew should be destroyed to the maximum extent, and the damaged grape leaves, branches and diseased fruit stalks should be pruned in time. The residual branches and rotten leaves should not be left in the vineyard, but should be taken out of the field and dealt with centrally. Pick the heart and tie the vine in time, cut the auxiliary tip, thinning the flower and fruit, and keep the vineyard ventilated and transparent. In addition, it is necessary to control the amount of nitrogen fertilizer application, timely re-application of phosphorus and potassium fertilizer, so as to enhance the disease resistance of grapevines.

On the basis of agricultural control, attention should be paid to drug control, and the basic agents for the prevention and control of grape powdery mildew are sulfur preparations, including stone sulfur mixture, sulfur powder, sulfur gel suspension and so on. Spraying protective fungicides must be persisted, this agent is used in the critical period before and after flowering of grapes, and it can also be used in combination with therapeutic agents after the disease of grapevines. Protective fungicides include chlorothalonil, agricultural antibiotic 120, Wuyisin and so on. The frequency of application depends on the specific conditions of the grapes, once every 7-10 days.