How to calculate the number of insect nets? What is the effect of different meshes?
The number of meshes refers to the particle size or thickness of the material. The general definition refers to the number of meshes in the area of 1 foot * 1 inch, that is, the number of meshes of the screen, and the number of meshes that the material can pass through is defined as how many Mesh number; china agricultural insect net is a new type of agricultural covering material. It is made of high-quality polyethylene as raw material, added with chemical additives such as anti-aging and anti-ultraviolet. Correct storage life of up to 3-5 years. Choose appropriate specifications – the specifications of organic vegetable insect control nets include width, aperture, wire diameter, color, etc. In particular, attention should be paid to the aperture; if the mesh is large, it will not achieve the proper insect-proof effect; if the mesh is small, the shading will be too much, which is not good for crop growth.
At present, the suitable mesh number is 20-32 mesh, the wire diameter is 0.18 mm, the width is 1.2-3.6 meters, and it is white. If you need to strengthen the shading effect, you can choose a black insect net. Silver-gray insect nets are better at preventing aphids. The biggest feature is that it can prevent insects and diseases, and greatly reduce the amount of pesticides used. It is the key technology of pollution-free vegetables and a simple, scientific and effective insect control measure.
The 25-mesh vegetable greenhouse insect-proof net has little effect on the temperature and relative humidity in the greenhouse, but it delayed the appearance of high temperature and low humidity in one day. In the experiment, the high temperature was delayed by about 4h, and the low humidity was delayed by about 2h. The 25-mesh insect-proof net covered with Certain shading effect. Therefore, it has a buffering effect on the rise of temperature and the fall of humidity in the shed; because the mesh of the 25-mesh insect-proof net is sparse and the shading rate is low, the high and low values of temperature and humidity are basically the same as the control.
40 mesh vegetable greenhouse insect-proof net has a greater influence on the temperature and relative humidity in the greenhouse than 25 mesh. The change trend of temperature and humidity in the shed covered with 40-mesh insect-proof net was basically the same as that of the control, but the change range decreased and the relative humidity increased. In cloudy weather, due to the dense mesh of the 40-mesh vegetable greenhouse insect-proof net, high temperature and low humidity occur in the greenhouse, which has a greater impact on the growth of vegetables.
Overall comparison, the 25-mesh mist net for sale covers little change in temperature and relative humidity, and has little impact on the growth of vegetables. At the same time, the 25-mesh insect net for sale can block most pests, such as Bemisia tabaci, cabbage caterpillar, cabbage borer, diamondback moth, Aphids, flea beetles, beet armyworms, Liriomyza sativa, Spodoptera litura, etc., also reduce the spread of virus diseases, sooty diseases and other diseases. In production, it is generally recommended to use about 25 mesh insect control nets.