Prevention and control of cotton boll rot

First, the light is poor, suitable for pathogen infection, disease is often serious, cotton rotten bolls are also more serious. Cotton boll rot is caused by the infection of many kinds of pathogens. In rainy years in summer and autumn, cotton field humidity is high and cotton plant closure is heavy. Ventilation accounts for 28.3% of boll disease. Rainfall days and rainfall in late August are the key factors affecting the occurrence of cotton boll blight in our province. During this period, there are 3-5 rainy days, and the disease will occur seriously. Extensive cotton field management, pruning or chemical control measures are not timely, plant growth, etc., are conducive to disease. 2. Cotton boll rot control method 1. Reasonable fertilization: increase organic fertilizer and phosphorus and potassium fertilizer, apply appropriate nitrogen fertilizer, prevent cotton plants from flourishing, reduce cotton canopy, and improve ventilation and light transmission. 2. Reasonable pruning: For cotton fields with too narrow row spacing and too early sealing, in order to reduce excessive field shading and improve light conditions and ventilation conditions in the middle and lower parts, the edge center should be removed as soon as possible, which can reduce the loss of buds and rotten bolls. 3. Chemical control: Chemical control is an important measure for comprehensive control of cotton boll rot, and targeted fungicide spraying should be carried out. 8-9 In January, when the weather forecast has several consecutive days of rainy weather, spray protection should be carried out in time. Spraying should be concentrated in the middle and lower parts of cotton plants. Commonly used agents are carbendazim 1000 times solution, 80% Penke WP diluted 500-600 times solution, 70% Chlorothalonil WP diluted 500 times solution, etc.