Microbial pesticides refer to pesticides that use living organisms such as bacteria, fungi, viruses, protozoa or genetically modified microorganisms as active ingredients. Microbial pesticides include Bacillus thuringiensis, Albicans, nuclear polykeratovirus, jinggangmycin, Clostridium C exotoxin, etc.
Compared with chemical pesticides, microbial pesticides do not pollute the environment, do not poison people and animals, do not harm natural enemies, and do not induce the generation of drug resistance, which is currently vigorously promoted as an efficient, low-toxicity, low-residue green pesticide.
In order to achieve better insecticidal and disease-proof effects, farmers often mix several pesticides. Microbial pesticides can also be reasonably mixed with chemical pesticides, which can not only improve the control effect and delay the resistance of diseases and insects, but also greatly reduce the use of chemical pesticides, reduce environmental pollution, and improve the quality and safety of agricultural products.
However, many growers do not understand the characteristics of microbial pesticides, so that there are many misunderstandings in the process of use, either the prevention and control effect is poor, or the medicinal effect cannot be exerted, and even the activity and role of microbial pesticides are lost. In order to better use microbial pesticides, Xiaobian briefly summarized this, hoping to help farmers.
1. Scientific storage
Microbial pesticides are live agents and must be kept in a place protected from light, ventilation, low temperature and dryness. Cannot be mixed with fungicides, antivirals and alkaline substances. Otherwise, it is easy to cause the death of living organisms and reduce the efficacy of the drug.
2. Master the temperature
The activity of microbial pesticides is directly related to temperature, the temperature is 10-27 ° C, as the temperature rises, the amount of pest feeding and absorption increases, and the bacterial spores or viruses enter the pest body after multiplying faster and more toxic, prompting the pest to die faster. Temperatures above 30 °C or below 10 °C are less effective in application. The test proves that under the condition of 20 ~ 30 °C, the control effect of biological pesticides is 1 to 2 times higher than that of 10 ~ 15 °C.
3. Grasp the humidity
Microbial pesticides are extremely sensitive to humidity requirements. The greater the humidity of the farmland environment, the more obvious the medicinal effect, especially the powdery biopesticide. Therefore, when spraying bacterial powder, it is necessary to firmly grasp the morning and evening dew when the dew is not dry, and when used on vegetables, melons and fruits, it is necessary to make the potion agent adhere well to the stems and leaves, so that the spores can multiply rapidly, and the pests as long as they eat the leaves, immediately produce medicinal effects and play a good control effect.
4. Avoid strong light
Ultraviolet rays have a fatal killing effect on microbial pesticides, when the sun is directly exposed for 30 to 60 minutes, the microbial mortality rate can reach 50% and more than 80%, so it is best to choose cloudy days, mornings, rain after spraying microbial pesticides, the best effect.
5. Avoid rain
Soon after rain spraying microbial pesticides, the bacterial liquid on the stems and leaves of crops will be leached off and reduce the efficacy, but if it rains lightly after 5 hours of application, it will not only not reduce the efficacy, but also have a synergistic effect. When applying the drug, avoid heavy rain and torrential rain to ensure insecticidal effect.
6. Symptomatic medication
Viral microbial pesticides are highly specific, generally only for one kind of pest, completely ineffective against other pests, such as the small cabbage moth granule virus can only be used to control the small cabbage moth. The scope of application is to kill lepidopteran larvae and is ineffective against aphids, mites and mite pests. Before use, it is necessary to investigate the occurrence of insect pests in the field, reasonably arrange the prevention and control period according to the occurrence of insect pests, and select the appropriate medication for the symptoms.
7. Advance medication
Because of their characteristics, microbial pesticides should be used in advance to prevent and reduce the occurrence of pests. Before sowing or before colonization, microbial pesticides can be used to soak seeds or dip roots, which can play a good preventive role. It is best to spray rice longitudinal leaf borer with Thuringiensis and Albicans in the early larval stage.
8. The concentration is appropriate and the scientific interval is appropriate
Timely application of the appropriate concentration of bacterial agents can ensure the effectiveness, such as bacterial insecticides generally every 1000 square meters with a number of live spores on 10 billion / g of the bacterial powder 2.2-2.5kg, the amount of insect mouth is large, the era overlaps, the age of insects is uneven, the unit area of a large amount of medication, the interval period is short. The control of small cabbage moths by Thuringiensis is carried out by 10-15 days for the control of large vegetable powder butterflies and 5-6 days for the control of trismoth borer.
9. Reasonable mixing
When mixing microbial pesticides, they should be treated differently, so that they should be used with one go and used up at one time. If mixed with white zombies, it is best to use up within 2 hours, otherwise once the spores germinate, they will lose their effectiveness.
Bacterial biopesticides should not be mixed with chemical fungicides, once mixed, the active bacterial spores of biological agents will be strangled and lose their due vitality.
Microbial fungicides can be mixed with most chemical insecticides and biological agents, but can not be mixed with alkaline drugs and systemic organophosphorus insecticides, such as trichoderma and other agents can be mixed with matrine, neem and other biological insecticides and chemical insecticides such as acetamidine.
At the same time, microbial insecticides, microbial fungicides, and microbial herbicides cannot be mixed with chemical fungicide pesticides. If mixed, the chemical agent will kill the microorganisms of these microorganisms and lose its efficacy.
Finally, when dispensing microbial pesticides, the secondary dilution method should also be used, and attention should be paid to spraying evenly when spraying, so that each part of the crop is sprayed wet and sprayed to prevent leakage spraying. In this way, the characteristics of microbial pesticides can be brought into play and the desired prevention and control effect can be achieved.