In spring, vegetable seedlings often cause seedlings to die in large areas due to sudden changes in the weather, improper management, and diseases and insect pests, causing losses to vegetable farmers. The reasons for the death of spring vegetables and their control measures are described below: YT-H706 YT-H706 Shenzhen Sunshine Technology Co.,Ltd , https://www.shenzhenyatwin.com
First, the disease dead seedlings. Mainly due to bed soil before sowing, nutrition soil is not disinfected or disinfected thoroughly, did not promptly spray after emergence, as well as improper temperature and humidity management of the seedbed, and so on, causing damping-off, blight occurs. Prevention and control measures: 1 seedbed soil disinfection, according to per square meter with 50% carbendazim seedbed 8-10 grams or 1 gram of Greenhenge, mixed with the appropriate amount of dry fine soil after spreading in the flour surface, turning soil after mixing When planting or preparing nutritious soil, add 50% carbendazim 80-100 grams or 5 grams of Greenhenge No. 1 to each cubic meter of nutrient soil, and mix well and fill in the nutrient bowl. 2 After 50-75% of the seedlings are unearthed, spray 50% carbendazim 500 times or 72.2% Prokary Water 1500 times to sterilize and prevent disease, then spray once every 7-10 days, timely uncovering the straw curtain and ventilation To prevent the seedbed from getting wet and the temperature is too high to induce the disease.
Second, drug killing seedlings. When seedbed soil is disinfected or nutritious soil is prepared, the dosage is too large, the bed soil is too dry after sowing, and the spraying concentration after emergence is too high, which can easily cause drug-killed seedlings. Preventive measures: Do not use excessive dose when disinfecting or preparing nutritious soil. After the treatment of the seedbed, to maintain a certain humidity, but the amount of water each should not be too much to see seedlings wet see dry is appropriate; to avoid seedbed humidity is too large, induced seedling roots, so timely ventilation and drainage, promote Moisture evaporates. Dry and fine soil and dry wood ash can be spread on the seedbeds on rainy days.
Third, freezing dead seedlings. At the time of the cold weather and low temperature, effective cold prevention measures were not taken in time, resulting in freezing and death of seedlings. Or the timing of seedlings is improper, the soil temperature of the seedbed is too low, and seedlings can not take root and cause dead seedlings after being divided into seedbeds. Prevention and control measures: 1 During the seedling raising period, pay attention to weather changes. In the cold current and low temperature, increase the coverage in a timely manner, and try to keep it dry to prevent it from being wetted by rain and snow and reduce the heat preservation effect. Temporary warming measures may be taken if conditions permit. 2 Reasonably increase the illumination, promote photosynthesis and nutrient accumulation, properly control watering, increase soil temperature of seedbed, ensure temperature requirement of seedlings, and improve cold resistance.
Fourth, dried dead seedlings. For seedlings that have not been ventilated for a long period of time, they are in a relatively high-humidity space. When the seedbed is ventilated, direct convection of cold air, or sudden release of air from the membrane, and the cover is blown by strong winds, will cause the hot and cold air inside and outside the seedbed to change excessively. Frequently, a sudden drop in temperature and humidity of the air caused the tender leaves to lose too much water and cause wilting. If the wilting lasts for a long time, the leaves cannot be restored and eventually become green and dry. This phenomenon is called air drying. Prevention and control measures: When ventilating seedbeds, they should be ventilated on the side of sheltered winds. The amount of ventilation should be from small to large, so that the seedlings have a process of adaptation, windy weather, pay attention to the pressure of the cover, and prevent the wind from blowing.