Pest and disease control is a very important and difficult management in greenhouse management, so now some farmers will cover the insect control net for insect control, which can basically eliminate the cabbage caterpillar, diamondback moth, aphids and other insect pests. But few farmers know what to pay attention to in their use.
Choose a suitable shading net: First of all, consider the mesh number, color and width of the yarn screen. If the mesh size is too small and the mesh size is too large, the effect of insect control will not be achieved; moreover, if the mesh size is too large and the mesh size is too small, it can prevent insects, but the ventilation is poor, resulting in high temperature and too much shading, which is not conducive to crop growth; generally, 22-24 mesh insect control net should be selected. In the spring and autumn season, compared with summer, the temperature is lower and the light is weaker, so the white insect-proof net should be chosen; in summer, black or silver-gray insect-proof net should be chosen for both shading and cooling; in areas where aphids and viral diseases occur seriously, silver-gray insect-proof net should be chosen for repelling aphids and preventing viral diseases.
Ⅱ. Pre-Coverage Processing
Before covering with insect-proof nets, soil disinfection and chemical weeding must be carried out. Before covering with insect-proof nets, pathogens and pests remaining in the soil must be killed, and the source of insects must be killed. This is the key link to ensure the effect of covering with insect-proof nets.
Ⅲ. Coverage Quality
Insect-proof nets should be completely closed and covered, compacted with earth near them and fixed with film-pressing wires. Insect-proof nets must be installed at the entrance and exit doors, and be careful to close them immediately when entering or leaving. The shelf height should be higher than that of crops to prevent vegetable leaves from sticking to insect-proof nets to prevent pests from feeding or laying eggs on vegetable leaves outside the nets; the insect-proof nets used for closing vents should not leave gaps between the nets and the covering materials such as film, so as not to leave access for pests; and the plastic insect-proof nets should be checked and repaired at any time. Holes and gaps.
When planting, seedlings should be brought into greenhouse with medicines, and healthy plants without pests and diseases should be selected.