Why are walnuts rotten?

Why are walnuts rotten? What caused it? Is there any way to prevent rotten walnut? Please also know the netizens to help introduce that walnut rotten fruit is mainly caused by anthracnose, walnut anthracnose not only harms fruit but also harms buds and shoots. Anthracnose will cause the damage rate of walnut fruit to 20%, 30%, and more than 80% seriously ill. Anthracnose will cause the fruit to blacken, rot and early fall, and the nucleolus will dry up, which not only reduces the yield, but also greatly reduces the commodity value, so the planting network has sorted out the harm and control methods of walnut anthracnose, which are listed in detail below for netizens' reference. Anthracnose harm to walnut: walnut anthracnose generally begins to harm the fruit after July 20 every year. After the walnut fruit is damaged, brown to dark brown, round or nearly round spots will appear on the pericarp, sunken in the center, and there are black spots in the diseased part, sometimes arranged in a wheel. When the humidity is high, the small part of the disease spot shows pink protuberance, that is, the conidia disk and conidia of the pathogen. When the disease of walnut is serious, a diseased fruit often has multiple disease spots. When the disease spot expands, the whole fruit blackens, rots to the inner pericarp, and the nucleolus has no edible value. When anthracnose was mild, the outer part of the shell or nucleolus blackened, which reduced the oil yield and nucleolus yield, or the disease spot was limited to the outer pericarp during fruit ripening, which had little effect on walnut. After the leaves were infected, the disease spots were irregular, some were withered and yellow along the edge of the 1cm, and some were long strips on both sides of the main vein. In severe cases, the whole leaves withered and yellowed and fell off. After the buds and twigs of seedlings and young trees are infected, they often wither down from the top, and the leaves fall off in a scorched shape. The main cause of anthracnose: walnut anthracnose is caused by fungal Colletotrichum anthracnose. The conidia of anthrax are transmitted by wind, rain and insects, invade from the wound and natural orifice, and can be re-infected many times. The onset and severity of walnut anthracnose are closely related to high temperature and high humidity. Rain Water is early and severe with high humidity and high humidity. The plant has small row spacing, poor ventilation and light transmission, and the disease is serious. The severity of anthracnose is also closely related to the varieties. Early-bearing thin-shell walnut is easy to occur and late-bearing walnut is resistant to disease. Prevention and control of rotten fruit caused by walnut anthracnose: first, remove the diseased fruit and diseased branches and leaves in time, burn them centrally, and reduce the source of the disease. Second, strengthen management, apply fertilizer reasonably, pay attention to the application of organic fertilizer, strengthen pruning work, and improve ventilation and light transmission conditions in the garden, so as to control the occurrence of diseases. Method 3. Diseased fruit was removed in time when diseased fruit was found, and 4000-fold solution of 80% tebuconazole, 3000-fold solution of difenoconazole and 80% mancozeb solution were sprayed 2-3 times. Method 4. If the walnut orchard is seriously affected, it can be sprayed with 3000 times of Ningnanmycin and used alternately with 10% difenoconazole. Generally, 600 times of copper acetate solution is sprayed before germination, and before the disease occurs after flowering, the control effect is better. How to water walnut trees the method of setting more fruits in walnut trees