What are the natural enemies of the spider? What is the most effective way to eliminate it?

Red spider, also known as cotton red spider, commonly known as big spider, big dragon, sand dragon, etc., scientific name spider mite, widely distributed, miscellaneous food habits, mainly harmful to a variety of vegetable crops, garden flowers and trees, citrus fruit trees and so on. So what are the natural enemies of red spiders? What is the most effective way to eliminate it? According to netizens, red spiders are not invincible. They often die in the mouths of Chinese lacewings, mite-eating ladybugs and mites.

Red spider belongs to the family Tetranychidae, the individual is small, the adult is about 0.2mm long, the body is round or oblong, mostly red or dark red. According to the biological habits of red spiders, agricultural, physical and chemical control measures can be applied.

Natural enemy control

Red spiders use natural enemies to control the population at the initial stage of occurrence and release predatory mites from flowering to fruit growth.

Before releasing predatory mites, the number of red spiders should be reduced as much as possible, and buflon was used for pest control. 5 to 10 days after application, predatory mites were released from 1:10 to 1:30 according to the benefit-to-damage ratio.

One predatory mite can not only prey on 300 and 500 red spiders, but also suck the eggs of harmful mites, which can effectively control the damage of red spiders.

Flower control

In the process of cultivating flowers, red spiders are common destroyers, such as rose, Milan, jasmine, kumquat, begonia, sweet-scented osmanthus, bergamot and so on. This kind of insect individual is very small, less than 1 mm, round or oval, orange or reddish brown, because the body is small and difficult to detect, once it is found that its damage, the flowers are often seriously damaged. This kind of insect damage way is to pierce the mouthparts into the leaves to suck the juice, so that the chlorophyll is destroyed, the leaves show grayish yellow spots or patches, and the leaves are orange, shedding, or even shedding.

In order to prevent and control the damage caused by red spiders, we should pay attention to observation at ordinary times, and when we find that the leaves are abnormal, we should carefully check the back of the leaves, individual leaves are damaged, and insect leaves can be removed; when more leaves occur, they should be sprayed as soon as possible. the commonly used pesticides are propargite, triclofenac, dimethoate, Huachongjing, and so on. Family flower can be prepared for flower sprayer, in 400ml water, propargite or dimethoate can drop 4 drops (equivalent to 2000 times), with triclofenac or dimethoate can drop 8 drops (equivalent to 1000 times), shake well after adding, then spray, spray evenly and thoughtfully, especially pay attention to spraying the back of leaves. When spraying, it is best to move the potted flowers outdoors. If you spray medicine indoors, do not approach food or utensils. After each use, pour out the excess liquid and wash the sprayer with clean water.

Citrus control

Citrus red spider is one of the most important insect pests in citrus cultivation. if it is not controlled in time, it will often cause a large number of fallen leaves of citrus trees, decline the tree potential, destroy the fruit epidermis and seriously affect the commerciality. therefore, the control of citrus red spiders is the primary task of citrus production. According to the practical research, it is considered that the prevention and control of red spiders should start from the following aspects.

First, agricultural measures, reasonable application of chemical fertilizer, reasonable proportion of nitrogen, phosphorus, potassium, avoid partial application of nitrogen fertilizer, excessive branches and leaves grow, new shoots grow frequently, provide an ideal breeding place for red spiders, orchard red spiders with excessive nitrogen often occur seriously; do a good job in winter cleaning and pruning to make trees ventilated and transparent, reduce insect sources and facilitate pesticide coverage!

Second, biological control, red spiders have many natural enemies in nature, such as predatory mites, ladybugs, budding molds and other natural enemies and microorganisms, promote grass cultivation, provide living environment for natural enemies, and avoid the use of broad-spectrum pesticides and fungicides. In production, such as spraying pyrethroid broad-spectrum pesticides to kill the natural enemies of red spiders, red spiders will develop quickly, and so will fungicides, such as copper and sulfur. During the sterilization process, the red spider natural enemy Thompson hairy bacteria was killed at the same time. If the red spider has an average of 3 adults per leaf can release predatory mites, there are Amblyseius Hu's mite on the market, each plant hanging a box of about 1000, the red spider population decreased by more than 95% in 30 days.

Third, chemical control, do a good job in orchard inspection at ordinary times, clear the garden in winter and prevent red spiders from clearing the garden in winter; mineral oil can be selected, such as green glume, diazepam, and other mineral oil with high safety, which can be mixed with 3000 times of avermectin or 1500 times of propargite in order to improve and enhance the insecticidal effect. Stone sulfur mixture can also be used to kill scale mites, but the insecticidal power is not very ideal and has great corrosion on pesticide application tools. Secondly, do a good job in the prevention and control of early spring, which is an important period for the prevention and control of red spiders throughout the year. At this time, due to low temperature, the activity of many temperature-sensitive acaricides is not ideal, such as propargite, triazoltin, mono-and diformamidine, and other pests occur at the same time. The medicament can choose physical action of high-quality mineral oil 200ml 300 times plus 2000 times cypermethrin, or fluazine 5000 times, buflurazine 15002000 times. The mixed mites with high population density are 5000 times more dangerous. In the spring shoot ripening period, there will be a peak if there is no good control in the early stage, so we should pay attention to the selection of suitable pesticides in production. The last is autumn, we must guard against red spiders before and after putting autumn shoots, otherwise harmful mites will harm autumn shoots and fruits!

Why are red spiders difficult to fight?

1. Red spiders are not insects, so many insecticides are ineffective against them

2. It is difficult for a red spider drug to cover four forms of red spider at the same time.

Red spiders have a large reproduction coefficient and frequent generations, and there are four forms of eggs, young mites, nymph mites and adult mites on a leaf. There is no acaricidal drug with high efficiency and quick effect on all four forms at the same time.

3. The red spider is small and hidden, so it is difficult to achieve full coverage by spraying, and it is easy to rebound after the effect has passed.

4. Environment and management model factors

There are many generations of diseases and insect pests in greenhouse producing areas, and insecticides need to be used for prevention. Some vegetable gardens must use copper preparations to prevent canker, the natural enemies of harmful mites are killed, and a large number of pesticides also make mites obtain very high resistance, so it is difficult to manage.

5. The practitioner does not master the relevant technology.

Difficulty one: hiding in the back of the leaf

Red spider is very small, to look carefully to see, but also like to hide in the back of the leaf to suck juice, when the front of the leaf shows symptoms, often the situation has been more serious.

Difficulty 2: spinning and cocooning

A large number of red spiders spinning cocoons can defend against pesticides and adverse environment, which is also one of the reasons why red spiders are difficult to cure.

Difficulty 3: strong drug resistance

Long-term single use of a small number of acaricides will lead to drug resistance or drug resistance of harmful mites.

Difficulty 4: security

The blooming period of red spiders coincides with the flowering and fruit-setting period of fruit trees, so medication should also take into account the safety of flowers and fruits, bees and humans.