Six key taboos to remember when using bacterial biological insecticides
Edible fungi suffer pest damage during the mycelium growth and mushroom fruiting stages due to the distinctive odor of the mycelium, so insecticides are often used when pest damage occurs. When pest damage occurs in edible fungi, the first step is to choose insecticides that are highly effective, low in toxicity, and have a short residual life, such as decis and dichlorvos; do not use banned substances such as benzene hexachloride (BHC) and DDT...
Bacterial biological insecticides have the advantages of a high insecticidal rate, no environmental pollution, safety to natural enemies, no harm to humans and livestock, and not inducing pest resistance. They are a new type of protective agent currently promoted for key use in pollution-free cultivation. Because their control effect depends mainly on the bacterial activity in the agent, the following points need to be kept in mind when using them:1. Avoid using inferior agents
They should be purchased from legitimate manufacturers and pesticide sales outlets to prevent counterfeits and inferior products, and attention should be paid to the production date, service life, and proper storage of the agent to prevent expiration and loss of efficacy. In addition, normal agent products generally contain a certain amount of bacteria; when the lid is opened there should be no foul odor, and sometimes there may be a fragrant smell (given off by the culture medium), while expired or fake products often produce an unusual odor or have no smell.
2. Avoid using at low temperatures
The active ingredients of bacterial biological insecticides are protein crystals and living spores. Under low-temperature conditions, the spores reproduce slowly in the pest's body, and the protein crystals are also less likely to take effect. Ambient temperatures of generally 10-35°C are suitable; if too low, it will affect the insects' feeding amount, and the control effect will be somewhat poorer.
3. Avoid dry environments
The bacterial spores in bacterial biological insecticides prefer humid environments, so the greater the field humidity when used, the higher the efficacy; especially when spraying powdered biological pesticide formulations, more attention should be paid to field humidity. Generally, bacterial powder formulations are sprayed in the early morning and at dusk when there is dew.
4. Avoid strong light
Ultraviolet rays in sunlight have a killing effect on spores; if the light is strong, ultraviolet rays will kill the bacteria. Therefore, bacterial biological insecticides should be sprayed on cloudy days or in areas with weak light. Generally, apply the pesticide before 10 a.m. on sunny days, or at dusk.
5. Avoid heavy rain washing
If moderate to heavy rain occurs shortly after spraying a bacterial biological insecticide, it will wash away the bacterial solution sprayed on the crop stems and leaves and reduce the efficacy. But if light rain falls 5 hours after application, it will not only fail to reduce the control effect, but will instead have a synergistic effect.
6. Avoid mixing with fungicides
When applying bacterial biological insecticides, never mix them with fungicides (such as carbendazim, thiophanate-methyl, etc.), otherwise it will easily lead to a serious reduction in the number of bacteria in the agent, thereby affecting the insecticidal effect. Therefore, even a sprayer that has been used for fungicides must be rinsed clean before being filled with bacterial biological insecticide.