An important requirement for good seedlings is to not carry pests. Seedling disease not only affects the growth of vegetables, reduces the yield, but also introduces the diseases and insects into the production shed, causing the occurrence of a large number of diseases and insect pests during the production period, resulting in an increase in the use of chemical pesticides, which has an impact on the ecological environment and the quality and safety of agricultural products. Therefore, the cultivation of disease-free, robust and healthy seedlings is the first step in achieving high quality and high yields of vegetables, and is also the first step in the prevention and control of pests and diseases. What problems should be paid attention to when vegetables are planted in the early spring? 1. Variety selection. For the pests with serious damages in the early spring, the pest-resistant species can be reasonably selected. For example, tomato root knot nematode can be used as the harm to choose the Cyclamen series, tomato yellowing leaf curl virus disease can be selected as Zhejiang powder 702, etc., and the early spring seedling temperature is still high. Low, so choose low-temperature, good early-maturing varieties. 2. Seed treatment. To prevent seed virus transmission, it is recommended to soak the seeds for 10 minutes with 10% trisodium phosphate solution or 0.2% potassium permanganate solution, wash with water, and soak in germination; soak with 50% carbendazim 500 times solution Vegetable seeds for 60 minutes to prevent wilt disease. 3. Shed room disinfection. The surface of the greenhouse can be sterilized with horseradish, fumigant, ozone or sulfur. Seed bed soil disinfection can be drip irrigation with 20% horseradish water emulsion, or after the whole planting fertilizer and watering with 30%?famemycin wettable powder 600 times or 50% carbendazim wettable powder 800 times evenly sprayed seedbed. 4. Nutrition soil preparation. The nursery soil is selected from the sorghum garden soil and the decomposed organic fertilizer which are sieved and mixed in a ratio of 7:3. 0.5 to 1 kg of compound fertilizer is added per cubic meter. Use well-developed organic fertilizers as base fertilizers to avoid pathogenic bacteria in the excreta or damage from burning seedlings. 5. Grafting. In order to reduce the harm of soil-borne diseases and increase yield, cucumbers, eggplants and other vegetables can be grafted and nursed. 6. Temperature and humidity control. If there are long-term low temperature and weak light conditions, warming measures should be taken in the nursery shed to prevent chilling or freezing injury. The floor heating line can be laid, and the ground temperature can be properly increased to promote seed germination and reduce the occurrence of diseases such as damping-off. After the seedlings are unearthed, the watering is controlled, the air is released in time, the humidity of the seedbed is lowered, and the temperature and humidity conditions suitable for the growth and development of the seedlings are created. 7. Sub-seedling hardening seedlings. Select the sunny morning sub-seedling, sub-seedling to avoid injury and root, choose to stay disease-free strong seedlings, eliminate weak seedlings, diseased seedlings, deformed seedlings. 5 to 7 days before colonization, move the nutrient pods or plugs to suppress the growth of the seedlings. Withdrawing the covering and increasing the ventilation, gradually reduce the temperature of the greenhouse and carry out the low-temperature hardening. 8. Pest prevention. The nursery shed must cover 50 mesh or more insecticidal nets, hang yellow boards, prevent small-sized insect pests such as whitefly and roundworm, spray alginic acid, plant immune proteins and other inducers to promote growth and enhance seedling disease resistance. 9. Pre-shelf drug prevention. In order to ensure that the seedlings are free of pests and diseases, the roots or seedlings of the cultivars should be rooted before the transplanting with Pythium oligo-spici, Bacillus subtilis, and Trichoderma spp. to prevent soil-transmitted diseases and enhance their resistance to diseases and insect pests; use of a broad spectrum of A detailed spray prevention of bactericidal and insecticidal agents. Hemodialysis Catheter,dialysis Catheter,powertrialysis dialysis catheter,peritoneal dialysis catheter,dialysis catheter kit Anesthesia Medical Co., Ltd. , https://www.honestymed.com