MySheen

Scientific use of bacterial biological insecticides

Published: 2024-11-22 Author: mysheen
Last Updated: 2024/11/22, During the period from rice sowing to seedling field, farmers should focus on the prevention and control of seed-borne diseases (evil seedling disease, seedling rice blast, dry tip nematode, etc.), gray planthopper, first generation borer and so on. In the rice breaking stage, emphasis should be placed on the control of diseases and insect pests such as rice planthopper, rice leaf borer, stem borer, panicle blast, rice false smut and so on. The rice planthopper was taken as the main control object at the heading stage of rice.

First, avoid using inferior medicine. In order to ensure the quality of the chemicals used, they should be purchased from regular manufacturers and points of sale to prevent fake and shoddy, and pay attention to the production date and service life of the agents as well as the reasonable storage and storage of the agents to prevent expiration. Second, avoid using at low temperature. The active ingredients of bacterial biopesticides are protein crystals and living buds. Under the condition of low temperature, spores reproduce slowly in pests, and protein crystals are not easy to function. Third, avoid dry environment. The spores of bacteria in bacterial biological insecticides prefer wet environment, so the higher the field humidity is, the higher the efficacy is, especially when spraying powdered biological pesticides. In general, bacterial powder is sprayed in the early morning and evening when there is dew, so that the bacterial agent can better stick to the stems and leaves of crops, promote spore reproduction and improve efficacy. It is better to spray vegetables with water on a foggy morning or half an hour before spraying. Fourth, avoid strong light. Ultraviolet rays in sunlight have a killing effect on spores. If the light is strong, ultraviolet rays will kill bacteria. According to the experiment, the death rate of spores is about 50% in direct sunlight for half an hour, and 80% in direct sunlight for one hour. In addition, ultraviolet radiation will deform and reduce the efficiency of parasporal crystals. Therefore, the spraying of bacterial biological insecticides should be carried out in cloudy days or weak light vegetable plots. The pesticide is usually applied before 10:00 or in the evening on a sunny day. Avoid washing in heavy rain. Shortly after spraying bacterial biological insecticides, in case of moderate to heavy rain, the bacterial sap sprayed on the stems and leaves of crops will be washed away and the efficacy will be reduced. However, if there is light rain after 5 hours of application, it will not reduce the control effect, but have a synergistic effect, because this is conducive to the rapid reproduction of bacterial spores in vivo and in vitro. Sixth, avoid mixed use with fungicides. When applying bacterial biological insecticides, do not mix with fungicides (such as carbendazim, topiramate, etc.), otherwise it will easily lead to a serious reduction in the number of bacteria in the agents, thus affecting the insecticidal effect. As a result, even sprayers that have been sprayed with fungicides have to be rinsed clean before they can be equipped with bacterial bioinsecticides.

 
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