1. Living habits: overlapping generations, surviving generations, weird and cunning rabbits (mostly feed on the back of leaves and lay eggs where the leaves are slightly rolled up). The first line of defense (leaf surface) is easy to annihilate; The second line of defense (Ye Bei's), this line of defense you can't eliminate, there will be residual enemies responsible for transmitting drug resistance information; The third line of defense (wing, vein edge, where the leaf edge is slightly rolled up) is the safest fortress. This line of defense is difficult to penetrate. When the potion arrives here, it will form a water film and be supported on both sides. Under the water film is a safe bomb shelter. Only with penetrant such as silica gel can it destroy its last fortress. Besides, there are so many leaves in citrus that you can't spray every leaf, which provides it with a chance to make a comeback, and also inherits the resistance gene to a certain acaricide for its next generation.
2. Acaricidal pesticides: there are many kinds, limited varieties, part-time, only contact with death (individual stomach toxicity). Plant sources and mineral sources are not easy to produce drug resistance, but due to temperature restrictions, phytotoxicity may occur; Some have good contact killing performance, but even natural enemies are killed, with strong results; Acaricides are also divided into temperature-sensitive and temperature-insensitive types, but some dealers do not pay attention to them and mix them at will; There are still many new varieties. When they are still in the boudoir (patent protection period), let manufacturers be love partners or invisible components and make acaricidal weapons. By the time they can get married (the patent protection period has passed), they will be old and yellow.
3. Human factors: the obscurity of selling drugs, the willfulness of using drugs, repeated use of one dose, and random addition of doses. Dealers do not know the performance and precautions of various acaricides; Do not record the file of each drug use of fruit farmers, and repeatedly distribute the acaricide used last time; Using temperature-sensitive acaricide at low temperature; Easy to use, profitable and continuous sales, so that fruit farmers can increase their consumption at will; This compound is not recommended because it will increase the possibility of drug resistance. Fruit farmers wait until the occurrence base of red spider is more, and then use drugs; I don't know the killing mechanism of acaricide, and I don't spray enough water. I think that if I increase the dose, I can kill Starscream. Blindly listen to the recommendation of the drug seller (the above dealer); After the outbreak of the red spider, after the first application, ten days later, no acaricide was used for pursuit; The first time I didn't press the foundation of Starscream, I thought this medicine was not good, so I quickly found another one, but I didn't know that I bought the same kind of product, but the trade name was different. Weeds in the orchard are cleaned up with herbicides, and there is no breeding environment for natural enemies.