Since November, there have been rare low-temperature and persistent cloudy smog and foggy weather in many northern parts of China. The production of greenhouse vegetables has been seriously affected, especially fruit and vegetable vegetables, which have weak growth, poor flowering results, serious diseases, and serious yields. Decline and even face the risk of production. To minimize losses, the following management recommendations are made.
Emergency measures
First, pay attention to temperature regulation during special periods
Long-term continuous cloudy smog, the temperature difference between day and night in the shed is small, which is not conducive to the growth and development of vegetables. In temperature management, it is necessary to ensure that the minimum temperature at night is above the minimum temperature of the birth limit (fruits and vegetables should be above 10 °C). It is also necessary to maintain a certain temperature difference between day and night. The temperature difference between day and night at around 10 °C is the best. If it is not reached, it must reach at least 5 °C. In the case of continuous low temperature and cloudy weather, in order to ensure the temperature, greenhouse warming and warming measures should be strengthened. An old shed film can be added to the grass, and two curtains are placed in the shed. Keep an eye on the weather and temperature, and add a layer of grass to the low temperature period. Conditional heating can be performed.
Second, take measures to increase light and fill light
During the daytime, when the temperature is guaranteed, the sunlight should be removed as much as possible to make full use of the scattered light to improve the indoor lighting conditions. The high-quality anti-fog dripping film is used to keep the film clean; reasonable plant adjustment and prevention of field closure; The reflective curtain (film) is suspended in the lower part of the wall; the reflective film is placed on the ground, and the fill light can be hung to fill the light and increase the illumination.
Third, control the humidity inside the shed
Controlling humidity in the shed is the key to preventing disease. Even if it is cloudy weather, it should be properly ventilated every day at the highest temperature before and after noon. The air release time is 10 to 15 minutes, and the air outlet is 10 to 15 cm wide to reduce the indoor humidity. At the same time minimize watering or watering.
Fourth, strengthen plant management
Pay attention to moderate flower thinning, reduce fruit set, reduce nutrient consumption, and improve the resistance of plants to low temperature and low light; when the middle and lower fruits are close to commercial fruit, they should be harvested in time to prevent falling.
V. Strengthen disease prevention and control
Under the condition of low temperature and low light, it is easy to induce vegetable diseases, and it is necessary to strengthen the prevention and treatment of diseases. In order not to increase the humidity in the greenhouse, try to use smoke, mist spray or dust to prevent and control.
6. Scientific management after low temperature and illuminating period
First, in the event of a sudden sunny day, it is necessary to take measures to look back during the noon glare. If there is a roller blind machine, the thermal insulation or grasshopper can be put down 1/2 to 2/3 in the noon glare period, and the light is weakened in the afternoon, and then the thermal insulation or grass is gradually rolled up; there is no roller blind machine. In the noon glare period, the grasshoppers can be placed at intervals. Should pay attention to observation, if the wilting is found, immediately increase the coverage of the shade area, and then gradually recover after recovery.
The second is to scientifically carry out fertilizer and water management, and promote the recovery of vegetables as soon as possible. Due to the cloudy weather, the temperature is low, the ground temperature is correspondingly low, the absorption capacity of vegetables for water and fertilizer is weakened, and the weather can be cleared by spraying urea, potassium dihydrogen phosphate or high-quality foliar fertilizer; after the temperature rises, combined with watering, After applying a high-quality elemental water-soluble fertilizer, it can also spray chitin, amino oligosaccharide, and Bi-protection to promote the vegetable to weaken as soon as possible.
Long-term measures
First, optimize the regional layout of the facility type
According to the regional distribution of smog distribution and effective light radiation, optimize the regional layout of greenhouses and plastic arch shed vegetables. Even cloudy days and smog have a great impact on the production of greenhouse vegetables in the greenhouse, and even lead to production. To take advantage of the winter production of solar greenhouses, it is necessary to ensure sufficient amount of light radiation. Areas with light or low haze and high effective light radiation should be used as the dominant production areas for greenhouse vegetable production; while plastic arch sheds are mainly produced in early spring and late autumn, and are less affected by winter haze. The production base, market demand, temperature and light conditions, etc. are considered as a shed type.
Second, adjust the variety of vegetables
Leafy vegetables and root-stem vegetables have lower requirements for temperature and light conditions. They are less affected by the cloudy days and haze than the fruits and vegetables. In addition, people’s diet has changed in recent years, and the pots and roots are the same. The demand for vegetables is increasing, and the growth period of these vegetables is short, labor-saving and labor-saving. They are listed on New Year's Day and Spring Festival, and the benefits are also good. Therefore, in areas with heavy fog and haze in winter, priority can be given to leafy vegetables. Classes, root vegetables.
Third, the mouth of the arrangement
Do a good job in the annual production plan, and arrange the period of continuous smog and continuous smog in the late stage and the late stage to avoid the production risks caused by cloudy days and haze.
Disclaimer: Some articles on this website are transferred from the Internet. If legal rights of third parties are involved, please inform this website. phone
We're professional Others Laparoscopy Surgery manufacturers and suppliers in China, specialized in providing high quality medical instruments with reasonable price. We warmly welcome you to buy or wholesale bulk Others Laparoscopy Surgery for sale here and get quotation from our factory.
Laparoscopic Devices,Laparoscopy Instrument Set,Laparoscopic Thyroid Instruments,Laparoscopic Surgical Instruments
Tonglu WANHE Medical Instrument Co., Ltd , https://www.tlvanhurhealth.com