How to use herbicides in winter
Generally speaking, the effect of weeding in winter will be higher than that in spring. Then to master this advantage, we must master the time of weeding in winter and the precautions for the selection of herbicide manufacturers in winter.
Reasonable selection of herbicide manufacturers' products, pesticides suitable for winter application. In general, stomach poisons and contact agents are less affected by temperature, and systemic and fumigants are more affected by temperature. For example, low temperature such as dichloride and dichlorvos will obviously affect the insecticidal effect, while pesticides such as deltamethrin, phoxim, and lime sulfur mixture can still play a better insecticidal effect when applied at lower temperature. Therefore, to control crop diseases and insect pests in winter, we should pay attention to the selection of pesticides that are less affected by temperature. 2. Choose the medicine during the sunny and high temperature period. Because when the temperature is high in winter, the activity range and respiration intensity of the pests increase, the food intake increases, and the liquid medicine is sprayed on the insect body, and more drugs are brought into the body, which is conducive to the poisoning effect.
Appropriately increase the dose. The lethal dose of pesticides to pests is not constant. The lower the temperature at room temperature, the lower the lethal dose of pests. Therefore, increasing the dose of pesticides in winter can prevent pests from dying after taking medicines. But it must not exceed the safe high concentration. When applying pesticides in winter, water should be added strictly according to the dilution ratio, and the amount of water should not be increased or decreased at will.
Properly extend the safety interval. The degradation rate of pesticides in winter slows down, and the pesticides remain in the crop for a relatively long time. When preventing and controlling diseases and insect pests of vegetable crops, it is necessary to appropriately extend the number of days (ie safety interval) from harvesting after the last application of the crop to ensure food safety. .
