Chinese cabbage is easy to produce green insects in autumn. How to control it more effectively?

Abstract: Chinese cabbage is prone to green insects in autumn, and these methods have lower pesticide residues.

Cabbage is one of the vegetables with the greatest demand in winter, especially in the northern vegetable market. Basically, a family can eat two or three bags of cabbage, pickled cabbage, stewed cabbage, vinegar cabbage and so on. Cabbage is indeed an indispensable good dish on the table in winter. But cabbage insects often occur, which really gives vegetable farmers a headache. Cabbage, which is growing well, is either full of holes or full of insect dung when it crawls over the leaves. It not only affects the appearance, but also affects the output.

So in addition to medication, what other feasible ways to prevent cabbage insects?

The occurrence stage of Pieris rapae. Pieris rapae is the larva of Pieris rapae, which generally begins to eat the mesophyll of cabbage after the third instar. Generally, the resistance of the larvae of Pieris rapae is relatively weak, which is the best period for drug control. Generally used drugs include bacterial insecticides, insect growth regulators, antibiotic insecticides and other high-efficiency and low-toxic agents, which are selected for control before the 3rd instar.

After reaching the adult, it is very difficult to kill the insect with the increase of drug resistance. However, no matter what kind of insecticide is used frequently and the dosage increases, there will be pesticide residues. Therefore, in addition to the use of pesticides, other methods should be considered for the control of Pieris rapae.

Feasible methods to control the outbreak of Pieris rapae.

Select cabbage varieties with strong insect resistance. At present, some of the cabbage varieties have insect resistance, such as Qingza 3, which can effectively reduce the incidence of pests such as Pieris rapae, but can not completely avoid the occurrence of Pieris rapae, but also cooperate with other pest control methods.

Prepare the land to clean up the vegetable field and rotate it reasonably. Before sowing cabbage and after the harvest of the last season, clean up the sundries in the field, especially the plant remains that are easy to induce Pieris rapae, may contain a large number of eggs, and soil disinfection can be carried out by soil insecticides or fungicides with high efficiency and low toxicity if necessary.

It is also introduced that Baneda Bika fertilizer can be used to improve the soil. It reduces the eggs and sources of worms from the source. Serious continuous cropping of Chinese cabbage is also the cause of the outbreak of cabbage green worms, so we can rotate Chinese cabbage with spring onions, ginger, garlic and other crops to avoid the harm of repeated cropping.

Physical insecticidal method combined with insecticides was used to kill cabbage insects in the early or middle and later stages of the outbreak.

At present, the physical insecticidal method is to use black light to trap and kill cabbage insects. By trapping and killing adults, the eggs can be reduced and the outbreak of cabbage insects can be avoided. The prevention and control of cabbage insects cannot be completely killed by physical methods alone. therefore, when cabbage insects break out, they should be combined with insecticides with high efficiency and low toxicity, and all kinds of pesticides should be used alternately when insecticides are used. to prevent green insects from developing drug resistance.

Put in the natural enemies of Pieris rapae and control the insects with insects. The natural enemies of Pieris rapae include golden wasp and Trichogramma, which can be put into the vegetable field at the right time when the outbreak of Pieris rapae, combined with black light to trap adults can also play a certain role in killing insects.

The prevention and control of Pieris rapae can only be based on prevention and control, and only rely on physical methods to kill insects, the effect is still limited, or should be combined with chemical control, especially in the areas with the outbreak of Pieris rapae should be sprayed as soon as possible to avoid the reduction of yield caused by the outbreak of cabbage. Affect the growth of cabbage heart.

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