First of all, many people think that since it is an expired pesticide, according to the general habits, it must be "deterioration, failure", and can no longer be sold or used. However, in fact, pesticides are a special commodity, and their shelf life is determined according to the expected control effects of plant diseases and insect pests under normal doses. Many expired pesticides, as long as the dosage is properly increased, strictly in accordance with scientific methods, still have good insecticidal and disease-preventing effects. General commodities such as expired foods are obviously "ineffective, deteriorating" or not "safe". They cannot be used to solve problems by eating more.
Secondly, pesticides are highly toxic and polluting, and we cannot destroy them easily. Even professional technicians who use special technical measures to destroy it can only minimize pollution and the cost of destruction is high. Therefore, it is not recommended to destroy all expired pesticides.
Third, before using the drug, we must see the date of manufacture and the shelf life. If the shelf life has not yet arrived, it should be used strictly according to the amount of guidance. If the shelf life is too late, it should be appropriately increased according to its efficacy. Because some pesticides are outdated, the efficacy will be reduced; some pesticides are outdated, but the efficacy remains the same. When using outdated pesticides, the initial use amount must be sprayed according to the instructional dosage. After 3-5 days after use, the results of killing the pests and diseases are observed. If the results are not ideal, the dosage can be basically increased in the original; After the spray is still not obvious, you need to change the pesticide or use the pesticide alternately; if it is effective after use, it can continue to be used.
Fourth, we must grasp the dosage according to the stage of crop development. Especially in the seedling stage of the crop, the leaf area is small, and the dosage should be reduced accordingly, but the spraying of pesticides should still be matched according to the proportion of the guidance. At other stages, an appropriate amount of expired pesticides can be added.
Finally, pesticides are sprayed evenly. When spraying pesticides, the syrup should always be connected to the pressure mark line of the air chamber. Under such pressure, the sprayed medicine will form fine droplets, which can be attached to the front and back of the blade on average. Generally, when spraying, the nozzle is placed under the crop blade, the mouth is facing upward, and the front and back of the blade can be sprayed evenly. It is not necessary to change the position of the nozzle. Generally, it is better to spray once, and it is not possible to spray multiple times at the same time. Otherwise it is prone to phytotoxicity.