During the annual sowing period of cotton, I often receive questions from farmers about the problem of cotton seedlings. We know that transgenic hybrid cotton has a slower growth than ordinary cotton at the seedling stage, and has weaker stress resistance. In case of severe low-temperature, rainy weather or high-temperature and other severe weather in April, it will inevitably result in a large area of ​​nutritional seedlings. Every year, cotton growers do not germinate or sprout after emergence, and farmers and seed distributors often have some disputes. The cause of a dead seedling in cotton seedlings 1. Severe weather. The continuous low temperature and rain after sowing was the main reason for the delayed emergence of cotton seedlings. In the cotton-growing region of Jianghan Plain, the low-temperature waterlogging type in the seedling stage accounted for 42.8% of the statistical year. 2. Dead seedlings due to disease. Soil moisture, large residual bacteria, low temperature, long time, can easily cause blight and anthrax. In general years, the incidence rate is 10 to 30%. In severe years, the incidence rate is 100%, and the rate of dead seedlings reaches 35% or more. Some old seedbeds are seriously affected. 3 fertilizer burning seedlings. Cotton seedlings have less roots and grow slowly. If there are too many trace fertilizers, especially ammonium bicarbonate or unfermented organic fertilizers, the phenomenon of burning seedlings is more serious. 4. Cover soil too thin or too thick. The thickness of the cover soil should be about 1.5 cm. Covering the ground is too thick to form rotten seeds in the presence of low temperatures; the cover soil is too thin, the loess soil loses water quickly, and the roots of the cotton seedlings are difficult to lower. 5. Watering too little or too much dead seedlings. The bauxite surface is wet, and the inside is dry. The cotton seed is not in good contact with the bauxite. Some of them are not seeded due to lack of water. Some of them are easy to form hanging gas seedlings to form weak seedlings or dead seedlings. The temperature of the seedbed is low, and the permeability is poor. The seeds are difficult to germinate. 6. Seedling soil affects seedlings. The new loam soil is conducive to the growth of cotton seedlings. The groundwater level in low-lying land and clay ground is high, humidity is high, seedlings are slow, and diseased seedlings are easily found. In addition, sandy loam seedlings, the temperature is difficult to control, easy to form burning seedlings. 7. Killing seedlings. There are many kinds of drug-killing seedlings, some of which are caused by excessive concentration of drugs to form burning seedlings. Some of them were caused by misuse of pesticides and caused death due to pesticides, but also because the sprayer did not wash the previously sprayed herbicide causing dead seedlings. Second, prevent pests prevent seedlings seedlings early measures 1. Disinfection prevention is indispensable. 1000 times broad-spectrum fungicide disinfection of soil cover soil. Immediately after the seedlings were wetted, copper preparations were used to protect the seedlings. In the event of low temperatures and low temperatures, bactericidal agents such as thiophanate-methyl 800 times should be sprayed. 2. Scientific management of the bed membrane, adjust the temperature and humidity. After sowing, the seedlings should be hermetically sealed and moisturized. When the temperature reaches 25°C, the temperature in the membrane has reached the temperature limit of the cotton seedlings, and it is necessary to cover the shading of the grass. After the seedlings are grown, the temperature should be raised to 30°C. Membrane ventilation was removed in the morning to avoid the formation of bruising seedlings at noon at high temperatures. In case of low temperature and rain, cover the membrane. 3. Control wet hazards. The moisture content of bauxite is 80%. The gutters should be drained and dehumidified around the seedbed. The seedbed should not be moisturized after pouring enough water before sowing. Keeping the seedbed dry can effectively reduce the probability of disease occurrence. 4. Rational use of fertilizer. The soil-fertilizer should be applied about 20 days before the last planting. The general seedbed can use 2 kg of high-quality imported compound fertilizer and 4 kg of decomposed cake fertilizer and 150 kg of water manure. 5. Prevent diseases. It is not appropriate to cover the membrane with a large concentration of pesticides, but also to use herbicides with caution. After use, it must be cleaned to avoid devastating phytotoxicity.