Four aspects of attention in the use of Bt insecticides

Bt is a bacterial insecticide, which belongs to a variety of Bacillus thuringiensis. It has a good effect on the control of Lepidoptera larvae. First of all, we should pay attention to the quality of Bt, generally requires more than 10 billion spores per milliliter (or 1 gram), the application concentration is 500 million 700 times, if the product contains low bacterial content, the concentration should be increased. Opening the bottle cap during inspection may indicate that it has expired if it is found to have a strange smell. two。 Do not mix Bt with fungicides such as carbendazim and topiramate. Sprayers that have been sprayed with fungicides should also be rinsed clean, otherwise the fungicides will kill some Bt bacteria, thus affecting the insecticidal effect. 3. Pay attention to the weather when using, preferably in cloudy days or weak light, if the sun is strong, ultraviolet rays will kill Bt bacteria. Spraying on sunny days is usually done before 10:00 or in the afternoon, preferably in the foggy morning. The temperature is generally 10-35 ℃, if it is too low, it will affect the insect food intake, and the control effect is poor. 4. When the field population density is large, in order to eliminate pests as soon as possible, a small amount of pyrethroid pesticides such as Shuding, Xingmianbao, Kung Fu can be added to the sprayer.