在薄膜温室通风孔安装防虫网有两个优点。一是减少虫害，防止昆虫进入温室，减少昆虫啃食蔬菜或花果作物的数量。二是降低农作物细菌性病毒病发生的概率，因为有些昆虫会携带不利于作物生长的细菌或病毒，阻断昆虫生长，也是防止细菌病毒对农作物危害的一种方法。
以上是两个优点的分析，但主要缺点都比较大，同时也是两个缺点。近年来，人们发现，安装防虫网后，其缺点主要影响温室通风。防虫网间隙很小，前期新安装的防虫网通风效果较好。但随着时间的推移，网上会有很多灰尘，甚至一些农作物的汁液和残渣，或者其他的灰尘和垃圾。经过一段时间后，防虫网基本上是密闭的，所以排气口就失去了原来的意义。
对于薄膜温室来说，一旦温室内的通风量降低，夏季温室内的温度就会升高，很容易对农作物造成高温伤害。安装防虫网的两个缺点是会增加温室的湿度，对温室内的植物产生不良影响。由于安装了防虫网，长时间的通风效果会降低，进而增加室内湿度。湿度一旦控制不好，就会给细菌和病毒的繁殖带来适宜的环境，进而影响农作物霜霉病或根腐病等病害。
以上是两个主要的优点和缺点。在日常生产中，要根据自己种植的作物考虑是否加防虫网，选择毛孔大的防虫网。市场上的防虫网大多是25目，所以以上分析主要集中在25目防虫网的优缺点上。
在生产中，防虫网的选择至关重要。夏季采用薄膜温室。通风是主要的冷却方式和主要的降湿措施。所以要谨慎选择。There are two advantages in installing insect net at the vent of film greenhouse.One is to reduce insect diseases,prevent insects from entering the greenhouse,and reduce the number of insects gnawing at vegetables or flower and fruit crops.The second is to reduce the probability of crop bacterial virus disease,because some insects will carry bacteria or viruses that are not good for the growth of crops,blocking insects,and also a way to prevent bacterial virus damage to crops.
The above are two advantages of analysis,but the main shortcomings are bigger,and also two shortcomings.In recent years,it has been found that after the installation of insect proof net,its disadvantages mainly affect the ventilation of greenhouse.The gap of the insect proof net is very small,and the ventilation effect of the newly installed anti insect net in the early stage is fairly good.But over time,there will be a lot of dust on the net,even some crop juice and residue,or other dust and garbage.After a period of time,the insect proof net is basically airtight,so the vent loses its original meaning.
For the film greenhouse,once the ventilation in the greenhouse decreases,the temperature in the greenhouse will increase in summer,which is easy to cause high temperature damage to crops.The two disadvantages of installing insect proof net are that it will increase the humidity of greenhouse and have a bad effect on the plants in the greenhouse.Because of the installation of insect proof net,the ventilation effect will be reduced for a long time,and then the indoor humidity will be increased.Once the humidity is not well controlled,it will bring a suitable environment for the reproduction of bacteria and viruses,and then affect crop downy mildew or root rot and other diseases.
The above are two main advantages and disadvantages.In daily production,we should consider whether to add insect prevention net or not according to the crops you plant,and choose the insect prevention net with large pores.Most of the anti insect nets on the market are 25 mesh,so the above analysis mainly focuses on the advantages and disadvantages of 25 mesh insect nets.
In the production,the selection of insect proof net is important.In summer,film greenhouse is used.Ventilation is the main cooling method and the main humidity reduction measure.So choose carefully.
