1. It can effectively prevent insects. After covering the insect net, it can basically avoid a variety of pests such as cabbage caterpillars, diamondback moths, and aphids. After agricultural products are covered with insect-proof nets, they can effectively avoid the damage of various pests such as cabbage caterpillars, diamondback moths, cabbage armyworms, Spodoptera litura, flea beetles, simian leaf beetles, aphids and so on. According to the test, the insect control net is 94-97% effective against cabbage cabbage caterpillars, diamondback moth, cowpea pod borer and Liriomyza sativa, and 90% against aphids.
2. It can prevent disease. Virus transmission can have disastrous consequences for greenhouse cultivation, especially by aphids. However, after the installation of the insect-proof net in the greenhouse, the transmission of the pests is cut off, which greatly reduces the incidence of viral diseases, and the control effect is about 80%.
3. Adjust the temperature, soil temperature and humidity. In the hot season, the greenhouse is covered with a white insect-proof net. The test shows that: in the hot July-August, in the 25-mesh white insect-proof net, the temperature in the morning and evening is the same as the open field, and the temperature is about 1 ℃ lower than the open field at noon on a sunny day. From March to April in early spring, the temperature in the shed covered by the insect-proof net is 1-2°C higher than that in the open field, and the temperature in the 5 cm ground is 0.5-1°C higher than that in the open field, which can effectively prevent frost. In addition, the insect-proof net can block part of the rainwater from falling into the shed, reduce the humidity in the field, reduce the incidence of disease, and reduce the evaporation of water in the greenhouse on sunny days.
4. Has shading effect. In summer, the light intensity is large, and the strong light will inhibit the vegetative growth of vegetables, especially leafy vegetables, and the insect-proof net can play a certain role in shading. The 20-22 mesh silver-gray insect-proof net generally has a shading rate of 20-25%.
Model selection
In autumn, many pests begin to move into the shed, especially some moth and butterfly pests. Due to the large size of these pests, vegetable farmers can use insect control nets with relatively few meshes, such as 30-60 mesh insect control nets. However, for those with many weeds and whiteflies outside the shed, it is necessary to prevent them from entering through the holes of the insect-proof net according to the smaller size of the whiteflies. It is recommended that vegetable farmers use denser insect-proof nets, such as 40-60 mesh.
Selection of color
For example, thrips have a strong tendency to blue. Using blue insect-proof nets can easily attract thrips outside the shed to the surrounding area. Once the insect-proof net is not tightly covered, a large number of thrips will enter the shed and cause harm; With the use of white insect-proof nets, this phenomenon will not occur in the greenhouse. When used in conjunction with shading nets, it is appropriate to choose white. There is also a silver-gray insect-proof net that has a good repelling effect on aphids, and the black insect-proof net has a significant shading effect, which is not suitable for use in winter and even cloudy days.
Generally compared with summer in spring and autumn, when the temperature is lower and the light is weaker, white insect-proof nets should be used; in summer, black or silver-gray insect-proof nets should be used in order to take into account the shading and cooling; in areas with serious aphids and virus diseases, in order to drive To avoid aphids and prevent virus diseases, silver-gray insect-proof nets should be used.
Precautions
1. Before sowing or planting, use high-temperature stuffy shed or spray low-toxic pesticides to kill parasite pupae and larvae in the soil.
2. When planting, the seedlings should be brought into the shed with medicine, and robust plants without pests and diseases should be selected.
3. Strengthen daily management. When entering and leaving the greenhouse, the door of the shed should be tightly closed, and the relevant utensils should be disinfected before agricultural operations to prevent the introduction of viruses, so as to ensure the effectiveness of the insect-proof net.
4. It is necessary to check the insect-proof net frequently for tears. Once found, it should be repaired in time to ensure that no pests invade in the greenhouse.
5. Ensure coverage quality. The insect-proof net should be fully enclosed and covered, and the surrounding area should be compacted with soil and firmly fixed with a lamination line; the doors of entering and leaving the large, medium shed and greenhouse must be installed with an insect-proof net, and pay attention to close it immediately when entering and leaving. Insect-proof nets cover cultivation in small arched sheds, and the height of the trellis should be significantly higher than that of the crops, so as to prevent vegetable leaves from sticking to the insect-proof nets, so as to prevent pests from eating outside the nets or laying eggs on vegetable leaves. There should be no gaps between the insect-proof net used for closing the air vent and the transparent cover, so as not to leave an entry and exit channel for pests.
6. Comprehensive supporting measures. In addition to insect-proof net coverage, combined with comprehensive supporting measures such as pest-resistant varieties, heat-resistant varieties, pollution-free package fertilizers, biological pesticides, non-polluting water sources, and micro-spraying and micro-irrigation, better results can be achieved.
7. Proper use and storage. After the insect-proof net is used in the field, it should be collected in time, washed, dried, and rolled to prolong its service life and increase economic benefits.
Physical control and biological control have the advantages of not polluting the environment, being safe for crops, people and animals, and for food. As a type of physical control, insect control nets are the needs of future agricultural development. I hope more farmers can master this method. , to achieve better economic and environmental benefits.