As temperatures rise gradually during the summer, the increase in the duration of light and the increase in intensity cause the growth of vegetables to enter the most prosperous period of the year. In addition to sufficient supply of fertilizer and water, how can we reduce pests and diseases at this stage? Occur, so that green pollution-free production? What are the special features of the summer management of greenhouse vegetables? What are the new technologies and new methods for the production of pollution-free vegetables? What are the precautions for the summer production of open vegetables? Two nets and one membrane In summer, the outside temperature is getting higher and higher. When the minimum temperature exceeds 15°C in the outside world, the vegetable production inside the facility needs day and night ventilation, and the ventilation volume is increased to ensure the normal growth of vegetables. At this time, greenhouses and other facilities The type does not need to function as a guarantee of temperature, and its function is changed to the isolation of pests and the prevention of rain. Because, with the increase of temperature, pest activity is also more frequent. With the increase of pests, pests and diseases caused by pests will gradually increase. With the gradual increase of rainfall, the production of open-air vegetables will also be affected to varying degrees, and measures to prevent rain and pests are particularly critical. "Two networks and one film" is what? The so-called "two networks" are shade nets and insect nets, and "a film" is a plastic film. The "two nets and one membrane" production technology of the vegetable facilities is the effective use of shade nets, insect nets and plastic sheds for over-summer production. Insect nets can reduce the risk of pests and diseases; shading nets can reduce the temperature in the greenhouse during the summer; plastic greenhouse membranes can provide moisture protection and prevent rain in the summer. Using these facilities and materials, the whole course of cooked vegetables from nursery to production is in a closed environment. This method is not only a vegetable safety summer production technology, but also an important pollution-free vegetable production measures. Shade net Shade net is a kind of mesh agricultural plastic cover material. The shading rate is generally 20% to 90%, and the shading net has more colors, and black and silver shade nets are used in vegetable production. The shade net has different colors and uses are not the same. The shading and cooling effect of the black net is better than that of the silver-gray net, which is suitable for the season of the summer and the vegetables with less light intensity requirements. The silver-gray net has good light transmission, and it has the function of avoiding maggots and preventing virus diseases. It is suitable for the early summer and early autumn seasons, as well as vegetable coverage with high light intensity requirements. When purchasing, it must be determined according to the light-requiring characteristics of crops, cultivation season, and regional weather conditions. The application time of sunshade nets is generally from June to August, which mainly plays the role of shading and cooling. When the outdoor temperature rises to about 30°C, it is very difficult to cool the interior of the facility through ventilation. Therefore, it is necessary to use the sunshade net for cooling. According to the changes in the weather and the growth of the plants, the time for uncovering can be flexibly controlled. Generally sunny days should cover the shade net from 10 am to 4 pm; shade nets should be removed on cloudy days. Fast-growing leafy vegetables are mainly covered in the early stage of growth; live shade nets cover the time of 10 to 15 days; seedling transplanting covers 7 to 10 days, and fast-growing vegetables such as parsley can be covered in full. Insect net With the increase of temperature in summer, pests will become more and more serious. Insect nets can be used to cover the cultivation of insects by blocking the insects into the shed, cut off the breeding pathways of pests, and effectively control the spread of various pests such as cabbage caterpillars, moths, locusts, triceratops, noctuids, leafminers, etc., and prevent the spread of the virus. The harm will greatly reduce the density of insect population and effectively block the spread of diseases. Insect-proof nets are mesh yarns with different mesh numbers made of high-density polyethylene as the main raw material. They can be used for the covering of various types of greenhouses, arch sheds, and horizontal sheds in field fields, etc. to cut off insect pests and enter cultivation. Facilities to block the spread of disease. At present, the use of insect-proof nets to cover the cultivation of vegetable production in summer has become an important technical means for vegetables to achieve safe production. For leafy vegetables, fruit vegetables, melons, beans, and other crops, full coverage can be carried out throughout the growth period, which can greatly reduce the application of chemical pesticides in vegetable fields, and provide guarantees for the production of high quality and safe fruits and vegetables. There are several points here to remind everyone when choosing an insect net. Because the insect nets are knitted with the screens of our windows, all of them have the problem of what the ordinary people call "the size of the nets." For this description of "net size", there is a concept that needs to be understood by everyone, that is, "number of items". The number of holes refers to the number of holes in a square centimeter area. In summer, the number of insect-proof meshes covered in the high-temperature season is too small, and the insect-proof effect is reduced. The use of an insect-repellent mesh with a density of 30-60 mesh is desirable. However, excessive density may affect the ventilation effect, and it is difficult to reduce the temperature and reduce the growth of vegetable crops. Plastic film For the plastic film in the “two nets and one filmâ€, the problem that needs to be noticed is that the plastic film is matched with other facilities. For the wintering production of greenhouses, greenhouses can continue to use the old plastic film. However, it is necessary to pay attention to the joint with the insect net, so that the entire greenhouse environment forms a completely closed system. The interface between the plastic film and the insect net should be overlapped by 20-30 cm. The lower end of the insect net should be buried in the soil to avoid gaps in the membrane, net and the ground, so that the insect protection will fail. Bumblebee Pollination Here, teachers have been particularly reminded that although the use of two networks and one membrane technology can basically block the spread of pests and diseases, it must be noted that the absence of transmission of pests and diseases does not mean that vegetables can be green and pollution-free. In the early summer greenhouse, the production of fruits and vegetables in the shed, the environment of high temperature and high humidity in the greenhouse, can easily affect pollen development and spread to produce the problem of flowering and fruit drop. The vegetable farmers usually take exogenous hormone spray flowers to promote sitting fruit, but With the increase of the temperature in summer, the amount of hormones needs to be gradually reduced to the minimum level of the recommended dosage. Improper control will result in the production of malformed fruits and fruit cracks in the fruit and vegetable products, which will seriously affect the quality of the product. We can also often market. See this vegetable product. How can we work to promote the normal flowering results of fruit and vegetables, but do not use hormones? You may wish to learn about the technical measures to use the bumblebee for pollination. Bumblebee pollination is what? The bumblebee is a species of the honeybee family. It is a relatively special pollinating bee. Its body size is large, usually 3 to 4 times that of the bees, and the body is covered with hairy, carrying a large amount of pollen, which contributes to pollination and Pollination is complete. The activity temperature is low, 8 °C or more can be out of the nest to visit flowers, is a highly efficient pollinator insects. Bumblebee pollination is actually the use of bees on the flowers to drive the flower pollination of vegetables, can completely replace the artificial. The use of bumblebees for pollination of greenhouse fruit and vegetable crops is a low-cost, high-efficiency and pollution-free modern high-tech agricultural technology measure. It can be used to pollinate tomatoes, green peppers, eggplants, strawberries, and other vegetables and fruit trees with a 30% increase in yield. the above. Where did the bees come from? At present, the market has finished the sale of the bumblebee pollinator, one box of one bumblebee colony, 80 to 100 heads of bees per box, and pollination area of ​​up to 1.5 to 2 acres. After the beehive is placed in the shed, it is left standing for a period of time to open the beehive, after which the pollination work is completed by the bumblebee and does not require any labor. Generally, 3 months of food is provided in the beehive, and no management work is required after putting it into the greenhouse. Bumblebees can completely replace all artificial pollination measures used in production. What are the advantages? The bumble bees have strong pollination and high pollination rates. After pollination, the individual fruit size is uniform, and the fruit shape is good. There is no abnormal fruit. The more seeds in the fruit, the thicker the flesh, the bigger the fruit and the more solid the texture, and the yield and quality are improved. In order to increase the market price of fruit and vegetable products and increase revenue. Today, with emphasis on food safety, the use of bumblebee pollination is not only easy to use, saves time and labor, but also can increase production, improve fruit quality, improve fruit taste, and eliminate hormone residues. It is an important measure to ensure food safety. . pay attention It should be noted that the use of bumblebees in solar greenhouses or plastic greenhouses requires 30 to 40 mesh insect screens at the vents to prevent bumblebees from drilling out of greenhouses. The interface between the insect screens and the vents should be flat. Do not have folds to prevent the bumblebee from boring. In addition, bumblebees are highly adaptable to temperature. But under continuous high temperature conditions, the bumblebee's lifespan will also be shortened. Attention should be paid to the ventilation or cooling of shaded rooms. Bumblebees are sensitive to pesticides. Bumblebees must be careful when using insecticides before they enter the shed. They should use some low-toxicity, low-residue pesticides. They can only be put into the bumblebees after the drug's residual period expires to prevent the bumblebee from poisoning after entering the shed. . Urethral Catheterization Kits,Suture Change Kits,Skin Preparation Kits,Oral Care Kits Henan Xianghe Medical Materials Co., Ltd. , https://www.xiangheweicai.com