The use of insect nets in vegetable production has many benefits. Now we will introduce the role, selection and use of insect nets as follows.
First, the role of insect nets
1. Insect protection. After covering the insect net in the vegetable field, the harms of various pests such as cabbage caterpillar, diamondback moth, Brassica julibriss, Spodoptera litura, yellow-bellied beetle, and roundworm can be basically eliminated.
2. Prevent disease. Viral disease is a catastrophic disease of many vegetables, mainly transmitted by insects, especially aphids. Because the insect nets cut off the transmission routes of pests, the incidence of viral diseases was greatly reduced, and the control effect was about 80%.
3. Adjust the temperature, soil temperature and humidity. The tests showed that in the hot summer season, white insect nets were used to cover the arches of greenhouses. The morning and evening temperatures in the greenhouses were the same as the open areas, and the sunny days were about 1°C lower than the open ground; in the early spring, from March to April, the insect nets covered the greenhouses. The inner air temperature is higher than 1°C～2°C. The 5cm ground temperature is 0.5°C～1°C higher than the open ground, which can effectively reduce the frost. The insect net can prevent some rainwater from falling into the shed, reduce the humidity in the field, reduce the incidence, and reduce the greenhouse in sunny days. The amount of moisture in the evaporation.
4. Cover the light. Summer light intensity, strong light will inhibit the vegetative growth of vegetables, especially leafy vegetables, and insect nets can play a certain degree of shading and anti-glare direct effect.
Second, the insect network selection
Insect nets are available in various colors such as black, white, and silver grey, and can be used to select the net color. When used alone, silver gray (silver gray has a good repellent effect against maggots) or black should be selected. When used in conjunction with shade nets, it is advisable to choose white. Generally, the mesh size is 20 to 40 mesh.
Third, the use of insect nets
1. Covered by greenhouses. Insect nets are directly covered on the scaffolds and compacted with soil or bricks. The roof line should be tightened to prevent the strong wind from opening. Usually in and out of the greenhouse to close the door, in order to prevent butterflies, moths fly into the shed to lay eggs.
2. Small arch cover. The insect nets were covered on the arches of small arches, and then they were poured directly on the nets until they were harvested.
Summer and autumn vegetables are generally covered with insect-proof nets. Vegetables with long growing period, high stalks, or vegetables that need to be racked need to be cultivated in large and medium sheds for easy management and harvesting. The fast-growing leafy vegetables cultivated in summer and autumn have a relatively short growing period and relatively concentrated harvesting, and can be covered by small arches. In late autumn, deep winter, and early spring anti-season cultivation, insect-proof nets can be installed at the air outlet of the greenhouse and compacted with a lamination line.
Fourth, pay attention to matters
1. Use high-temperature stuffy sheds or spray low-toxic pesticides to kill parasites and larvae in the soil before sowing or planting.
2. When planting seedlings, it is advisable to bring herbs into the shed and pick out robust plants without pests and diseases.
3. Strengthen day-to-day management, in and out of the greenhouse to shut the shed tightly, sterilize the relevant utensils before carrying out the agricultural operation, and prevent the virus from being introduced from the wound to ensure the use of the insect net.
4. Always inspect the insect nets for tears (especially if they have a long service life). If they are found, they should be promptly repaired to ensure that there is no pest invasion.
Metal Disposable Fiber Optic Laryngoscope
Disposable Laryngoscope Set,Neonatal Laryngoscope Blade Sizes,Fiber Optic Laryngoscope Blades,Laryngoscope Blades And Handles
Jiangsu Yongle Medical Technology Co., Ltd. , https://www.jsylmedical.com