Shading net and insect-proof net covering cultivation is a new vegetable protection cultivation technology developed in recent years, which plays a very effective role in the over-summer and off-season cultivation of vegetables.
The main technologies of these two forms of protection are introduced as follows:
1. The functions and benefits of the net for sun shade mainly include four aspects:
One is to block strong light and reduce high temperature. Generally, the shading rate can reach 35% to 75%, which has a significant cooling effect;
The second is to prevent rainstorms and hail disasters;
The third is to reduce evaporation, protect moisture and prevent drought;
The fourth is to avoid pests and diseases, using silver-gray net for sun shade to cover, the aphid avoidance effect is 89% to 100%, and the disease prevention effect is 88.9% to 95.5%.
2. Several issues that should be paid attention to when covering the sunnet for sun shade:
①The floating surface is covered from sowing to the emergence of the seedlings. It is not necessary to open the net management, but it must be noted that the net should be opened in the evening after the emergence. Floating surface coverage can also be carried out after transplanting and planting and before slowing down the seedlings, but it should be managed by day and night cover.
②The trellis should be covered after emergence and slow seedling.
③The melons, eggplants, and beans vegetables that are planted in spring and harvested in summer can be covered with frost protection after planting. They can be covered on small arched sheds or small arched sheds in large arched sheds. The effect is better, but it should be managed day and night.
④The black net is suitable for the production of vegetables with weak light requirements, and the white net is suitable for light-loving vegetables. The black net is suitable for short-term coverage, and the white net is suitable for the coverage of the whole growth period. After the black net is covered, it should be strictly managed according to different vegetables and different growth periods of vegetables, while the white net is not strict.
⑤The summer coverage is mainly at noon on sunny days, and can be removed in the morning and evening and on cloudy days. On sunny days, the net is generally covered from 9:00 a.m. to 3:00 p.m.
Insect-proof net is a new type of covering material, which not only has the advantages of shading, but also has the function of preventing insects.
1. Covering form of insect mesh protection netting
①The cover of the middle shed is to cover the insect-proof net on the scaffold. In this way, the utilization rate of the scaffolding is improved, and the management of entering the scaffolding is convenient.
② Covering the small shed is to cover the insect-proof net on the small scaffolding. This method is not limited by the scaffolding, requires less investment, is easier to popularize and applies, and can receive the same effect of preventing insects and disasters and protecting vegetables. However, the height of the small trellis should be higher than the height of the newly cultivated vegetables, so as to prevent the vegetables from clinging to the insect-proof net, and there is an opportunity for pests to feed and lay eggs.
2. Insect-proof net covering technology
①It must be covered in the whole growth period. The insect mesh protection netting is less shading, and it does not need to be uncovered day and night or the front cover and back. It should be covered throughout the entire process, so as not to give pests a chance to invade, in order to obtain satisfactory insect-proof effect, the two sides should be compacted with bricks or soil blocks. The network cable needs to be pressed firmly to prevent it from being blown away by the wind.
②Choose the appropriate specification. The specifications of the insect net mainly include amplitude, aperture, wire diameter, color and so on. In particular, the aperture and the density of the insect net are generally calculated in terms of mesh. If the mesh is too small, the mesh is too large, and the insect-proof effect cannot be achieved; if the mesh is too large, the mesh is small, although it is insect-proof, it will increase the cost.
At present, the recommended number of meshes used in production is 24 to 30 meshes. The wire (wire) has a diameter of 14 to 18 mm, an amplitude of 1.0 to 1.8 meters, and is mainly white.