Scientific spraying of insecticides

In order to achieve the best insecticidal effect in the use of pesticides to control crop pests, in addition to the correct selection and appropriate use of pesticides, special attention should be paid to the following two problems that are easy to be ignored. According to the harmful parts of pests, different pesticides and different application methods should be selected and delivered in place. For the pests that harm the roots, the insecticides are applied to the roots or in the sowing ditches; for the pests that feed on the back of the leaves, the liquid is sprayed on the opposite side of the leaves; the control of red bollworm and cotton bollworm is applied to the flower buds, green bolls and the tip of the group; the seedlings are poisoned when the stem borer is withered; the white panicle is sprayed or poured; the liquid is sprayed to the base of rice plants to control rice planthoppers and rice leafhoppers. To control Spodoptera litura, spray the liquid on the buds and young pods. In addition, according to the feeding mode of piercing mouthparts for hidden pests such as cotton aphid, red spider, rice planthopper and rice leafhopper, insecticides with strong internal absorption can be absorbed and transmitted to other parts of the plant to achieve the purpose of drug delivery. According to the climatic characteristics and the diurnal activity law of pests, the pesticide should be applied at a favorable time. The suitable time for pesticide application is from 9 am to 10:00 and after 4 pm. Because after 9: 00 in the morning, the dew on the crop leaves has dried, and it is the time when the activity of sunrise pests is at its peak. At this time, the application of pesticide will not affect the control effect because of the dew dilution, but also make the pests come into direct contact with pesticides and increase the chance of pest poisoning. After 4 o'clock in the afternoon, the light weakens, and it is when flying activities and nocturnal pests are about to go out, at this time, the pesticide can be applied to crops in advance. When the pests come out or feed at dusk or at night, they will be exposed to venom or poisoned to death, and at the same time, the loss of evaporation and photolysis can be avoided.