The targeted selection of pesticides has saved some of the drug-resistant pests, and as the resistance of the pests has increased, the amount of pesticides has increased. As a result of this cycle, it has entered a vicious circle with no endings, spears and shields. The duel is getting worse. Many farmers are deeply touched, and now the pests are getting harder and harder to kill.
Where does the pest resistance come from?
Agricultural pests are prone to drug resistance, often associated with small size, wide source of food, reproductive rate and strong adaptability. The mechanisms by which pests develop resistance are mainly mentioned in these several ways.
The selection theory believes that there is a resistance gene for the drug in the population before the drug is administered, and the susceptible genotype individual is eliminated due to the selection effect of the drug, so that the proportion of the resistant genotype individual is increased, and finally the resistant population is formed.
The gene mutation theory is thought to be caused by a genetic mutation caused by the use of the drug. After the drug is used, a large number of sensitive individuals are eliminated, and individuals who have survived genetic mutations are survived.
According to the gene amplification theory, the pest has a resistance gene before the administration, and the resistance gene has a geometric base increased due to the use of the agent.
Black-headed owl
This kind of cockroaches has caused many places of garlic and leeks to be close to the harvest. The small factories of the big factories have a lot of special effects and medicinal products. The feedback results are not ideal.
And although some organophosphorus pesticides have been banned in many areas, farmers still use it sneakyly. However, the control effect is not ideal. The use of chlorpyrifos and phoxim in single-agent mixture, the use of one mu of land is calculated in kilograms, and it is still not ideal. It also has some effect on the use of phorate, but it is very difficult to completely die.
At present, various formulations have been tried, and the maximum flow is dinotefuran, clothianidin, avermectin, chlorpyrifos, phoxim and chlorfenapyr. And the combination of beta-cypermethrin, lambda-cypermethrin, cypermethrin, and the like. It is also useful to use imidacloprid, acetamiprid, thiamethoxam, etc. in combination with other products.
Root knot nematode
Root-knot nematodes are very harmful in many vegetable crops, field crops and fruit trees. Some literatures refer to them as nematodes because of their invisibility to the naked eye. They are also referred to as pests.
At present, the most widely used to control nematodes is avermectin, emulsifiable concentrate, water-milk, granules, spreading, ditching, acupoint application, and flushing. Because of its relatively economical reasons, the amount of use is very large. It is precisely because of this, the resistance is also very obvious after years of use, and another reason is that avermectin is difficult to displace in the soil, resulting in its resistance to nematodes is getting worse.
Thiazolidine is a product that is currently calling for a high level of avermectin. In addition to the first granules, major manufacturers are gradually developing single-agent and mixed-water emulsions, emulsifiable formulations, solutionable agents, etc. Liquid dosage form. At present, a small number of regions have reported resistance, but since the cost has just been reduced, it has not been widely used, and the resistance has not shown a too serious trend.
Fluopyram is a product that has not yet responded to resistance. Personally, it should be the reason why the cost is too high. Not many farmers are willing to use it repeatedly. After all, it is too expensive.
Next week, we will introduce whitefly, lepidopteran pest, and jumper. It will also include method of effectively prevent drug-resistant pests.
If you want to solve these problems, please inquiry us.
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