How to improve the control effect of biological insecticides
2022-08-28 04:03:29
In recent years, with the increasing pollution-free productivity of major cities across the country, pollution-free cultivation techniques have received extensive attention. Among various cultivation techniques, the application technology of bio-insecticides plays an important role as the core of pollution-free cultivation technology. At present, biopesticides popularized in agricultural production mainly include Bacillus thuringiensis (bt), avermectin, smectin (nicotine, matrine), etc. How to improve their control effect?
1. Defining the mechanism of action, selecting suitable bacterial bacteria, viruses and other pathogenic microorganisms must be ingested by the insect mouth and infected by the digestive tract to kill the host, generally only effective for chewing mouthparts pests, but not for inserting needles A sucking mouthparts pest that sucks juice from plant phloem. The main target pests of Bacillus thuringiensis are chewing mouthparts pests (such as lepidoptera, coleoptera, etc.), but they are powerless to sucking mouthparts pests such as aphids, planthoppers, and whiteflies. This situation is caused by two major categories. The pest feeding pattern and the mode of action of the entomopathogenic microorganisms on the host. What kind of pathogenic microorganisms can effectively kill sucking pests? According to research at home and abroad, only fungi can infect and kill sucking pests, because fungal pathogens generally invade host insects through the body wall without taking a photo from the mouthparts. In. At present, the fungal preparations for microbial control in China only have Beauveria bassiana preparations for controlling pine caterpillars and corn borer. Abamectin is an antibacterial insecticide and acaricide. It mainly has stomach poisoning and contact killing effect on pests. It has almost no systemic and fumigation effects. It can enter the body through insect stomata or claw pad, and has the effect of cortical flow. It affects the life of pests by hindering the normal function of the nervous system. Tobacco and ginseng are plant insecticides, which have stomach poisoning, contact killing and fumigation effects on pests. The mechanism of poisoning the pests is to paralyze their nerves. The vapor of smog and alkali can invade the body from any part of the worm body. Poisoning effect. Therefore, it is necessary to clarify the mechanism of action of various bio-insecticides, and to select the best microbial agents for different target pests for prevention and treatment.
2. According to the object of prevention and control, it is reasonable to grasp the different kinds of pests and different pests of different pests. The sensitivity of different insects to biological insecticides is different. It is necessary to select different kinds of biological pesticides and application concentration according to the sensitivity of pests in order to receive good. Control effect. For example, Pieris rapae is more sensitive to Bacillus thuringiensis and avermectin, and can be controlled by avermectin 3500-4500 times solution or Bacillus thuringiensis 500-1000 times solution. While Spodoptera litura is less sensitive to avermectin and Bacillus thuringiensis, 100-200 times solution should be used for prevention and treatment. According to experiments, the sensitivity of different vegetable pests to avermectin and Bacillus thuringiensis is: the cabbage caterpillar is larger than the jumper (worm), which is larger than the diamondback moth than the bean pod, which is larger than the Spodoptera litura.
3. For different insects, choose the method of use for the feeding of large insects such as cabbage butterfly, rice aphid, etc., using spray method has a good spinning effect. Plutella xylostella larvae prefer to feed on the back of the leaf, and it is necessary to spray the bacterial liquid onto the front and back sides of the leaf to achieve better control effect. When Spodoptera litura was first hatched, it was bitten and eaten, and it was dispersed after 2 years of age. Therefore, it is advisable to carry out foliar spray control during the initial incubation period. The newly hatched larvae of Helicoverpa armigera and Tobacco larvae first take the egg shell and then damage the tender stem, young leaves and fruit, so the egg-preserving effect is best. Rice borers enter the pupa during the day after entering the 2nd instar, and go out to eat in the evening. Therefore, it is better to spray at a lower age. To control corn mash, it is necessary to make the bacterium into toxic soil, and spreading it in the corn stalk is the best. Therefore, it is necessary to use drugs rationally for different pests to ensure better control effects.
4. According to different microbial agents, choosing the best weather temperature and sunlight have a certain influence on the control effect of Bacillus thuringiensis. If the temperature is too high, the crystal toxin structure of Bacillus thuringiensis can be destroyed, thereby affecting the control effect, and the sunlight can also reduce the insecticidal activity of Bacillus thuringiensis. Some trials have shown that the application rate of larvae at 8 o'clock in the morning is 20%-30% lower than that of larvae applied at 4 o'clock in the afternoon. Therefore, when using in the field, try to choose the afternoon with an average daily temperature of about 20 °C, cloudy or sunny. It will be carried out later. The biological activity of avermectin is related to temperature. The higher the temperature, the higher the biological activity and the positive temperature effect. Therefore, avermectin is more suitable for the control of vegetable pests in hot summer and autumn.
5. Mixed with chemical pesticides in the case of large pest occurrences and mixed with a variety of pests, avermectin can be used with pedicol or eucalypt, or bt plus insecticidal double-mixed spray can achieve both purpose. To alleviate the resistance of pests to biological pesticides. Bt, avermectin, smoke and ginseng are used interchangeably with chemical pesticides Ruijinte, Kayanke, Wanling, and Taibao. However, bt and avermectin cannot be mixed with alkaline pesticides. (Wu Fang, Song Aiqing, Chemical Industry Town, Mengzhou City, Henan Province, China)
Source of information: Jiaozuo City Institute of Agricultural Sciences, Henan Province
1. Defining the mechanism of action, selecting suitable bacterial bacteria, viruses and other pathogenic microorganisms must be ingested by the insect mouth and infected by the digestive tract to kill the host, generally only effective for chewing mouthparts pests, but not for inserting needles A sucking mouthparts pest that sucks juice from plant phloem. The main target pests of Bacillus thuringiensis are chewing mouthparts pests (such as lepidoptera, coleoptera, etc.), but they are powerless to sucking mouthparts pests such as aphids, planthoppers, and whiteflies. This situation is caused by two major categories. The pest feeding pattern and the mode of action of the entomopathogenic microorganisms on the host. What kind of pathogenic microorganisms can effectively kill sucking pests? According to research at home and abroad, only fungi can infect and kill sucking pests, because fungal pathogens generally invade host insects through the body wall without taking a photo from the mouthparts. In. At present, the fungal preparations for microbial control in China only have Beauveria bassiana preparations for controlling pine caterpillars and corn borer. Abamectin is an antibacterial insecticide and acaricide. It mainly has stomach poisoning and contact killing effect on pests. It has almost no systemic and fumigation effects. It can enter the body through insect stomata or claw pad, and has the effect of cortical flow. It affects the life of pests by hindering the normal function of the nervous system. Tobacco and ginseng are plant insecticides, which have stomach poisoning, contact killing and fumigation effects on pests. The mechanism of poisoning the pests is to paralyze their nerves. The vapor of smog and alkali can invade the body from any part of the worm body. Poisoning effect. Therefore, it is necessary to clarify the mechanism of action of various bio-insecticides, and to select the best microbial agents for different target pests for prevention and treatment.
2. According to the object of prevention and control, it is reasonable to grasp the different kinds of pests and different pests of different pests. The sensitivity of different insects to biological insecticides is different. It is necessary to select different kinds of biological pesticides and application concentration according to the sensitivity of pests in order to receive good. Control effect. For example, Pieris rapae is more sensitive to Bacillus thuringiensis and avermectin, and can be controlled by avermectin 3500-4500 times solution or Bacillus thuringiensis 500-1000 times solution. While Spodoptera litura is less sensitive to avermectin and Bacillus thuringiensis, 100-200 times solution should be used for prevention and treatment. According to experiments, the sensitivity of different vegetable pests to avermectin and Bacillus thuringiensis is: the cabbage caterpillar is larger than the jumper (worm), which is larger than the diamondback moth than the bean pod, which is larger than the Spodoptera litura.
3. For different insects, choose the method of use for the feeding of large insects such as cabbage butterfly, rice aphid, etc., using spray method has a good spinning effect. Plutella xylostella larvae prefer to feed on the back of the leaf, and it is necessary to spray the bacterial liquid onto the front and back sides of the leaf to achieve better control effect. When Spodoptera litura was first hatched, it was bitten and eaten, and it was dispersed after 2 years of age. Therefore, it is advisable to carry out foliar spray control during the initial incubation period. The newly hatched larvae of Helicoverpa armigera and Tobacco larvae first take the egg shell and then damage the tender stem, young leaves and fruit, so the egg-preserving effect is best. Rice borers enter the pupa during the day after entering the 2nd instar, and go out to eat in the evening. Therefore, it is better to spray at a lower age. To control corn mash, it is necessary to make the bacterium into toxic soil, and spreading it in the corn stalk is the best. Therefore, it is necessary to use drugs rationally for different pests to ensure better control effects.
4. According to different microbial agents, choosing the best weather temperature and sunlight have a certain influence on the control effect of Bacillus thuringiensis. If the temperature is too high, the crystal toxin structure of Bacillus thuringiensis can be destroyed, thereby affecting the control effect, and the sunlight can also reduce the insecticidal activity of Bacillus thuringiensis. Some trials have shown that the application rate of larvae at 8 o'clock in the morning is 20%-30% lower than that of larvae applied at 4 o'clock in the afternoon. Therefore, when using in the field, try to choose the afternoon with an average daily temperature of about 20 °C, cloudy or sunny. It will be carried out later. The biological activity of avermectin is related to temperature. The higher the temperature, the higher the biological activity and the positive temperature effect. Therefore, avermectin is more suitable for the control of vegetable pests in hot summer and autumn.
5. Mixed with chemical pesticides in the case of large pest occurrences and mixed with a variety of pests, avermectin can be used with pedicol or eucalypt, or bt plus insecticidal double-mixed spray can achieve both purpose. To alleviate the resistance of pests to biological pesticides. Bt, avermectin, smoke and ginseng are used interchangeably with chemical pesticides Ruijinte, Kayanke, Wanling, and Taibao. However, bt and avermectin cannot be mixed with alkaline pesticides. (Wu Fang, Song Aiqing, Chemical Industry Town, Mengzhou City, Henan Province, China)
Source of information: Jiaozuo City Institute of Agricultural Sciences, Henan Province
ã€Comment】 ã€Print this article】 ã€Close this page】 ã€Large, medium and small】
Led Lighting,Holiday Decoration Christmas Lights,Waterproof Amusement Lighting,Square Led Pixel Light
Shen zhen SH LED Technology Co.,Ltd , https://www.pixellightsolutions.com