I. Variety selection
Leaf lettuce is mainly eaten as a part of lettuce, and it is also known as lettuce because it is mainly eaten raw. Leaves with deep cracks, leaf shrinkage, adaptability, easy to cultivate. Excellent varieties include Guangzhou Dongshan lettuce (soft-tailed lettuce), glass lettuce, lettuce king, and the United States.
Second, nursery
Lettuce (lettuce) is a semi-cold-resistant vegetable. It enjoys cool and humid climatic conditions. It is not resistant to heat. If it is to be used for annual sales, it can be produced by combining open field and protected land, which can basically meet the needs of the whole year.
In general, seedling quantity per 667m2 is 25~30g, and the ratio of seedbed area to colonization area is about 1:20. Lettuce seeds are small and germinate quickly, and dry seeds are generally used more often. Seeds are generally treated only with air. Such as soaking germination, first soaked with cold water for 5 ~ 6h, then placed at 16 ~ 18 °C under conditions of light germination. After 2~3d, budding can occur. Seedlings can be sown on the field in the production field, and nutritious soil blocks, paper bags or nursery supplies can also be used.
Lettuce is very adaptable to the soil. Nursery bed soil is suitable for organic-rich, loose-breathable loam or clay loam. 50% of decomposed horse manure and 50% of garden soil are used for nursery, and 20 g of urea is added per cubic meter of bed soil. And superphosphate 200g, after sieving, mix well and spread 5cm thick on the seedbed (10cm thick for seedbed laying). Before sowing, the seedbed is poured into the bottom water, and 0.5 cm thick fine soil is spread after the water is soaked. Generally, the seeding rate per square meter is 5~10g. After sowing, cover fine damp soil 0.5cm, keep the soil temperature at 15~18°C, cover the plastic film or grasshopper insulation, generally can be excavated after 3~5d. If the seedlings are planted in open field, about 10 days after emergence (1 leaf stage), the seedlings can be carried out so as not to affect the growth of seedlings. In the 2~3 leaf stage, it can be transplanted. The seedling distance should be 6~8cm. Seedlings and strains for each seedling. Bottom water before transplanting, soiling after planting, and planting seedlings should not be too deep. In the period of transplanting, seedlings should be kept warm and moist, and the temperature should be around 20°C. After easing the seedlings, it is necessary to reduce the humidity and cool the temperature, and the temperature drops to around 16°C. The key to this period is to promote the seedlings to be strong and not overwhelming. Winter and spring nursery seedlings should pay attention to maintain suitable temperature, use good lighting, easy to ventilate the greenhouse as a seedbed, proper control of watering, non-humidity is too large; summer and autumn open nursery, high temperatures unfavorable growth, need to be shade, rain, cooling Measures.
Third, colonization
Seedling age 30 ~ 35d, seedlings with 5 to 6 true leaves colonization. Before planting, every 667m2 of cultivating high-quality farmyard fertilizer 4000kg, compound fertilizer 20kg, Pu Shi shallow ploughing 15 ~ 20cm, and then do 1m wide rake, rake high 10 ~ 15cm. In autumn and winter seasons, in order to increase the ground temperature, the ground can be covered with film for 1 week in advance, and when the local temperature is stable above 8°C, planting can be achieved. Plant spacing 1720cm, should be planted with soil mulching, planting depth to ignore the heart and leaves is appropriate, timely planting water. The temperature of facility cultivation is controlled at 12~22°C. In the hot season, colonization should be done in the morning on the day of planting, covering the shade net and transplanting in the evening.
Fourth, field management
Watering
After the seedlings are transplanted, they can be topdressed with water. Leaf lettuce is extremely sensitive to soil moisture during growth, weak root absorption capacity, and large leaf area, so it consumes large amounts of water. The soil should be kept moist during cultivation, and it is generally poured in 5 to 7 days. When the temperature is low in spring, the amount of water should be small. Watering should not only ensure the plant's need for water, but also can not be excessive, and the humidity in the field should not be too large to prevent the occurrence of disease.
2. Weeding
After planting and regenerating seedlings, we should carry out cultivating and weeding to increase soil permeability and promote root development.
3. Fertilization
Need more nitrogen fertilizer and a certain amount of potash fertilizer, every 667m2 can be topdressed with water urea 10kg, 30d before harvest to stop the application of available nitrogen fertilizer to prevent excessive accumulation of nitrate in the leaves. In addition, 0.2% potassium dihydrogen phosphate solution should also be sprayed on the leaves.
4. Temperature control
Lettuce is not tolerant to high humidity. When the temperature exceeds 25°C, it should be ventilated, cooled or shaded. At the same time, lettuce is afraid of leeches, so there is no water in the urns and it must be drained in time after the rain. After the hot summer rains, it is necessary to use well water to feed the garden. The stems and leaves of lettuce are tender and juicy. When working in the field, care must be taken not to damage the stems and leaves or the roots, otherwise susceptible to disease. When the temperature is high and the soil moisture is high, when the dew is to be picked up, remove the yellow, old, and residual leaves near the ground to prevent infection.
V. Harvesting
Leaf lettuce, its stems and leaves can be picked at any time before aging. However, the harvest period with the highest yield and the best value for the commodity is better when the leaves are fully grown and the green leaves are thick and tender. If the leaf ball is gently pressed by hand, there is a certain bearing force, and when the leaf ball is moderately tight, the harvest is best. Harvested late in the summer and autumn seasons, the buds within the ball are rapidly elongating and the leaf balls lose their value. For loose-leafed lettuces, leaflets can be picked and leaves can be picked, and the picked leaves can be placed on the market, and the whole plant can also be cut off. When the cabbage lettuce is harvested, it is cut off from the surface and the external old leaves are removed. 3 to 4 outer leaves are reserved outside the leaf bulb and can be packaged and listed.
Face Recognition Camera Series
Launched by Tiandy Technology,Face recognition is a series of AI products and solutions that adopt independent AI chip and deep learning algorithm. It focuses on human and vehicle with high accuracy, enabling users to fast act on defined targets. Based on Tiandy's advanced technologies, ,Face recognition series makes your video intelligent, simple and inclusive.
Intelligent: Face recognition series is powered by AI chip and deep learning algorithm. It provides various features that realize accurate alarms for human and vehicle, as well as quick target search, maximizing resources to increase overall efficiency.
Simple: Face recognition series offers simple configuration, especially for SMD Plus that can be enabled by just a single button. It eases your daily job and also empowers you with better business decisions.
Inclusive: Face recognition series is cost-effective that everyone can enjoy the benefits of AI advancement. With affordable prices and easy configuration, WizSense aims to fast accelerate the AI adoption in the industry and brings AI to everyone`s daily life.
Nvr Face Recognition,Face Capture Bullet Camera,Face Recognition Camera Series,Starlight Face Capture Bullet Camera
TD Cloud Security Co.Ltd , https://www.cctvcameraexpert.com