Among the vegetables infestation diseases, diseases caused by fungi were the most, followed by bacterial diseases. Among these diseases, fungal diseases and bacterial diseases, viral diseases, and non-invasive diseases have similar symptoms and should not be distinguished. In order to enable farmers to correctly identify and effectively prevent and control, their identification and chemical control methods are now described as follows:
Fungal diseases
Diseases caused by fungi can exhibit spots, wilting, malformations, and other diseases. However, bacterial diseases can also cause the same symptoms. The main difference is that bacterial diseases can be seen in the site of the spider or flocculent bacteria Filament, and some mycelia such as sclerotia metamorphosis. There are a variety of molds on the surface of the affected area, which is an important feature to identify fungal diseases. There are many kinds of fungi, such as downy mildew, powdery mildew, gray mold, disease, and blight of vegetables, causing the most serious damage.
For the prevention of fungal diseases, generally 72.2% of Precedure, 15% of Triconin wettable powder, 50% of Quickening powder, 64% of WP, 50% of carbendazim wettable powder And other chemical agents for prevention and treatment.
Bacterial diseases
The vegetable diseases caused by bacteria mainly include spots, streaks, ulcers, wilting and decay. Most of the lesions showed acute necrotic spots. In the early stages, the lesions were translucent and immersed in water. The edges often had oily heads and chlorotic yellow indole rings. Under humid conditions, the diseased areas overflowed with pyometha and formed a significant disease.
Chemical control of the disease, the general choice of 72% of the agricultural streptomycin WP, 77% of the WP can be killed, 25% Delocarbazin aqueous solution and other chemical agents for prevention and treatment.
Viral diseases
Vegetable virus diseases are mostly plant-wide chronic diseases, and external appearance symptoms often include mosaics, chlorosis, ring spots, blemishes, clumps, and leaf shrinkage. Virus disease has no symptoms only in its condition, which is confused with fungal diseases and bacterial diseases. The difference lies in the fact that the occurrence of viral diseases has obvious spread from point to surface. The pathological condition of diseased plants often begins at the top and then spreads to other parts of the plant. The spread of the virus depends on insects, sap and graft infections. Virus diseases are aggravated under conditions of high temperature and drought. The occurrence of non-infectious diseases is more uniform and does not show a point-to-face expansion. The diseased plants are often the whole plant, the plants can not be infected, and the occurrence of diseases is closely related to the adverse environment and other factors.
For the prevention and treatment of viral diseases, chemical agents such as 1.5% of the plant disease and Ling emulsion, 20% of the virus A wettable powder, and 83 activators are generally used for prevention and treatment.