Attentions before and after covering anti insect netting

Anti insect netting is like window screen, with high tensile strength, UV resistance, heat resistance, water resistance, corrosion resistance, aging resistance，non-toxic and tasteless, the service life is generally 4-6 years, up to 10 years. It not only has the advantages of sunshade net, but also overcomes the shortcomings of sunshade net, which is worthy of vigorous promotion.

1.  Role of Anti Insect Netting

1） Frost-proof

Fruit trees at young fruit stage and fruit ripening stage are in the freezing and early spring low temperature season, which are vulnerable to frost damage, causing chilling injury or freezing injury. The application of anti insect netting covering not only helps to increase the temperature and humidity in the net, but also prevents frost injury on fruit surface by isolation of anti insect netting. It has a very obvious effect on preventing frost injury in young loquat fruit stage and cold injury in mature citrus fruit stage.

2)  Prevention of Diseases and insects

After covering orchards and nurseries with anti insect netting, the occurrence and transmission routes of fruit pests such as aphids, psylla, fruit-sucking armyworm, carnivorous insects and fruit flies are blocked, so as to achieve the purpose of controlling these pests, especially the pests of aphids, Psylla and other vectors, and to prevent and control citrus yellow dragon disease and decline disease. The spread of diseases such as pitaya fruit and blueberry fruit flies plays an important role.

3)  Fruit drop prevention

Fruit ripening period is a rainstorm weather in summer. If anti insect netting is used to cover the fruit, it will reduce the fruit drop caused by rainstorm during fruit ripening period, especially in the rainy years of Pitaya fruit, blueberry and bayberry fruit ripening period, which has more obvious effect on reducing fruit drop.

4)  Improving Temperature and Illumination

Covering anti insect netting can reduce light intensity, adjust soil temperature and air temperature and humidity, reduce precipitation in net room, reduce water evaporation in net room, and reduce transpiration of leaves. After covering anti insect netting, the relative humidity of air was higher than that of the control, and the humidity was the highest in rainy days, but the difference was the smallest and the increase was the lowest. With the increase of relative humidity in the net chamber, the transpiration of fruit trees like citrus leaves can be reduced. Water affects fruit quality development through precipitation and air relative humidity, which is more conducive to fruit growth and development, and fruit quality is good.

Covering methods of pest-proof net fruit trees:

1) Shed type: first of all, the shelf is built. The shelf is fastened by a slot between the shelves. Anti insect netting is covered on the shelf. The ground is compacted with cement, and the front door of the greenhouse is left behind.

2) Cover type: directly cover the fruit trees with anti insect netting, supported by bamboo poles, single or multiple plants can be selected to cover at the same time. It is easy to operate and reduce expenditure, but it will cause inconvenience in field operation and management. It is mainly suitable for short-term, seasonal frost-proof, rainstorm-proof, bird-proof and so on. If frost-proof and bird-proof are in full maturity, it will be easy to operate and manage in the field. Drosophila and birds are harmful.

2. Scope of Application

1) Leaf vegetable is a vegetable that urban and rural residents like to eat in summer and autumn. Leaf vegetable has the characteristics of fast growth and short cycle, but there are many pests in open field production, serious pesticide pollution, and citizens dare not eat it. The pesticide pollution can be greatly reduced by covering cultivation with anti insect netting.

2) Melons and fruits covered with anti insect netting are susceptible to viral diseases in summer and autumn. After the application of anti insect netting, the transmission pathway of aphids is cut off and the harm of viral diseases is alleviated.

3) Nursery is the season of growing vegetable seedlings in autumn and winter from June to August every year. It is also a period of high humidity, heavy rain and frequent pests, which makes it difficult to grow seedlings. After using anti insect netting, the vegetable seedling emergence rate is high, the seedling growth rate is high, and the seedling quality is good, thus winning the initiative of autumn and winter crop production.

3. Points of Use

Anti insect netting are relatively simple to use, but the following points should be noted.

1) It is necessary to cover the whole period with anti insect netting. However, it does not need to cover day and night or front and back. Full coverage should be made. Both sides are compacted with bricks or earth. Satisfactory pest control effect can be achieved only if the opportunity of pest invasion is not given. In general wind conditions, pressure wire can be used. In case of 5-6 gale, the pressure wire should be pulled up to prevent gale from lifting the net.

2) Choosing suitable specifications of anti insect netting mainly includes width, aperture, color and so on. Especially, the aperture and the number of insect-proof meshes are too small and the meshes are too big to achieve the desired insect-proof effect. Too many meshes, too small meshes, although insect control will increase the cost of insect control nets.

3) In addition to pest control net coverage, combined with comprehensive supporting measures such as disease and insect resistant varieties, heat resistant varieties, pollution-free organic fertilizer, biological pesticides, pollution-free water sources, micro-sprinkler micro-irrigation, etc., can achieve better results.

4) After proper use and storage of anti insect netting in the field, they should be collected in time, washed, dried and rolled up so as to prolong their service life and increase economic benefits.

In the process of using the anti insect netting in greenhouse, we must pay attention to several details, so as to play a good role in the process of using it.

1)  First of all, in the selection of anti insect netting in greenhouse, the mesh number, color and width of yarn net should be considered. If the mesh size is too large, the effect of insect control will not be achieved; and if the mesh size is too small, it can prevent insects, but the ventilation is poor, resulting in high temperature and too much shading, it is not conducive to crop growth.  Generally, 22-24 objective anti insect netting should be selected. In the spring and autumn season, compared with summer, the temperature is lower and the light is weaker, so the white anti insect netting should be chosen; in summer, black or silver-gray anti insect netting should be chosen for both shading and cooling; in areas where aphids and viral diseases occur seriously, silver-gray anti insect netting should be chosen for repelling aphids and preventing viral diseases.

2) Ensure the quality of coverage. Anti insect netting should be completely enclosed and covered. They should be compacted with earth around them and fixed firmly with film-pressing wires. Installation of anti insect netting is necessary for doors entering and leaving large, medium and greenhouses, and attention should be paid to closing them immediately when entering and leaving. The height of the shelf is obviously higher than that of the crop, so as to prevent the insect pests from feeding outside the net or laying eggs on the vegetable leaves. The anti insect netting used for closing the vent should not leave a gap between the net and the transparent cover, so as not to leave a passage for the pests. Inspect and repair the holes and cracks in the anti insect netting  at any time.

3)  Insect control: seeds, soil, plastic shed or greenhouse skeleton, frame material, etc. may contain pests and eggs. Before planting crops, seeds, soil, shelf skeleton and shelf materials must be treated with pest control nets. This is the key link to ensure the cultivation effect of pest control nets, and to prevent pests and diseases from occurring in large numbers in the nets and causing serious damage.

4)  Selecting suitable varieties for indoor planting in the net, attention should be paid to row spacing and plant spacing in the planting process, and appropriate sparse planting.

5) Fruit trees should be covered with sunshade net, the soil should be plowed deeply, and the amount of basic fertilizer applied, such as decomposed farm manure and compound fertilizer, should be enough to ensure that crops can grow well when they are properly topdressed during their growth and development.

6)  Anti insect netting s can keep warm and moist. Therefore, in field management, we should pay attention to the temperature and humidity of nets indoors, ventilate and drain moisture in time after watering, so as to avoid diseases caused by excessive temperature and humidity.