First, there are obvious spots or spots on the main symptoms, and the medicinal symptoms of different agents are different.
2. Drugs are used during the cause of the onset of high temperature. The moisture in the medicinal solution quickly evaporates, and the concentration of the medicinal solution is increased, which is easy to cause drug harm.
3. Scientific medication of prevention and control methods refers to the use of pesticides economy, safe, and effective to achieve no pollution and no harm. Therefore, the right medicine should be achieved, understand the nature and characteristics of the pharmaceutical agent, master the characteristics of the prevention and control objects, select pesticides correctly, strictly use the prescribed concentration, and the medicine should be combined. Both pesticides are mixed properly, which can promote strengths and avoid weaknesses, and play a role in increasing efficiency. Mixed medicines generally do not exceed 3 types. It is best to use river water to distribute medicine. Data or wettable powder prepared with hard water can easily cause drug harm. When spraying drugs, the humidity should not be too large. If the air humidity is large, it should be damp. Spraying medicines should be meticulous and thoughtful, and the fog should be small to avoid excessive local medication. During the timely medication, we should generally avoid drugs such as flowers and seedlings such as flowers and seedlings. At the same time, avoid medication at noon high temperature at noon. At this time
4. When remedial measures are damaged, the soil should be cultivated in time to apply an appropriate amount of nitrogen fertilizer to promote the recovery growth. When the leaves and plants are severely damaged, they should be watered in time to add phosphorus and potassium fertilizers, plow and loose soil, promote root development, and enhance recovery capabilities.