1 The selection of greenhouse insect nets should first consider the number of meshes, the color of the meshes and the width of the meshes. If the mesh number is too small and the mesh is too large, it will not have the effect of preventing insects; if the mesh number is too small, it can prevent insects, but poor ventilation will cause high temperature and excessive shade, which is not conducive to the growth of crops. Generally, 22-24 mesh mosquito nets are used. 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 selected to consider shading and cooling; in areas with serious aphids and virus diseases, Silver grey insect nets should be used to repel aphids and prevent viral diseases.

2 In order to ensure the quality of coverage, the black-coated insect screen should be fully enclosed, tightly covered with soil, and firmly fixed with lamination lines; the doors of large and medium-sized greenhouses and greenhouses must be installed with insect-proof nets, and be careful to close them immediately when entering and leaving. The height of the trellis should be significantly higher than the height of the crops in the vaulted shed to prevent pests from feeding or laying eggs on the leaves of the plants. There must be no gaps between the insect nets used to seal the vents and the transparent cover, so as not to allow passage of pests. Check and repair holes and gaps in insect nets at any time.
3. Seeds, soil, plastic greenhouse or greenhouse skeleton and frame materials may contain insect eggs. Before vegetable planting, black coating insect screen treatment on seeds, soil, scaffold skeleton and skeleton material is the key link to ensure the effect of insect-proof net covering cultivation.