1. Variety selection Choose varieties with strong cold tolerance, disease resistance, and strong adaptability, such as Emperor, Salinas, Dahu 659, etc. The seedbed should choose fertile sandy loam with strong water and fertilizer retention capabilities. 2. Seedling preparation. Because the lettuce seeds are small, the seedbed cultivation requirements are strict, the ground preparation should be fine, and the bed soil should be finely crushed and leveled. Apply 10 kg of fully decomposed and finely divided farmyard manure, 0.3 kg of diammonium phosphate, and 0.3 kg of potassium dihydrogen phosphate per 10 square meter seedbed. Spread the ground evenly, till 10-12 cm, till and mix evenly and level it down. 3. Seed treatment Lettuce can be sowed with dry seeds or soaked to promote germination. When sowing dry seeds, dress the seeds with 75% chlorothalonil wettable powder equivalent to 0.3% of the dry weight of the seeds before sowing, and sow the seeds immediately after mixing, not overnight. When soaking seeds to accelerate germination, first soak the seeds in clean water at about 20°C for 3~4 hours. After scrubbing, drain the water, put it in a wet gauze bag or pot, and place it in an environment of 20°C to accelerate the germination. Wash with clean water once a day. After drying, continue to germinate the buds, and the buds will be ready for 2~3 days. When the temperature is too high under natural conditions, the germination can be placed in a wellbore or in a cave, etc. The temperature should be controlled at 15-20℃. 4. Before sowing, pour the seedbed with foot water, while the water has not been infiltrated, sieve the soil to level the border surface, sieve 0.1~0.2 cm thick fine soil after the water seeps, and then sow. The amount of seed used per hectare is 375-450 grams. In order to cultivate strong seedlings and prevent the formation of tall seedlings or weak seedlings, the seedlings should not be too dense, generally 1 gram per square meter of seedbed is appropriate. In order to sow evenly, the seeds can be mixed with sand and spread twice, and then sieve the soil to cover 0.3-0.5 cm. In order to prevent water loss, you can spread rice straw, wheat straw or mulch film on the border surface according to the ground temperature. To prevent ants and crickets from eating seeds, spray dimethoate and dichlorvos on the bed surface after sowing. 5. Seedling management. After sowing, the bed temperature should be kept at 20~25℃ and the border surface should be moist. The seedlings can be harvested within 3~5 days. If the temperature is too high, shading should be appropriate to create a cool and humid environment to facilitate the healthy growth of seedlings. When the seedlings are just unearthed, the cover of the border surface should be removed in time to prevent the formation of tall seedlings with excessively elongated hypocotyls. After emergence, 18~20℃ during the day and 8~10℃ at night. Seven to 10 days after emergence, when the seedlings have two leaves and one heart, the seedlings should be divided in time with a distance of 3 to 5 cm. After seedling division, it must be sprayed with 500 times solution of potassium dihydrogen phosphate or irrigated with water. In the seedling stage, it is necessary to spray 1 to 2 times of 75% chlorothalonil WP or 70% thiophanate methyl WP 600 to 800 times to prevent and control diseases in the seedling stage. The seedling age is 25 to 35 days, and it can be planted when there are 4 to 5 true leaves. Disclaimer: Some articles on this website are transferred from the Internet. If the legal rights of a third party are involved, please inform this website for processing. phone Food additives are compounds or natural substances added to food for the purpose of improving the color, aroma, and taste of food, as well as for the needs of anti-corrosion and processing technology. At present, there are 23 categories of food additives, with more than 2,000 varieties, including acidity regulators, anticaking agents, defoamers, antioxidants, bleaching agents, leavening agents, coloring agents, color retention agents, enzyme preparations, and flavor enhancers, nutritional fortifiers, preservatives, Sweeteners, thickeners, spices, etc. Erythritol, Sweetener, Pigment, XOS , Carotene, fish oil Xi'an Gawen Biotechnology Co., Ltd , https://www.ahualynbios.com