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棉花枯萎病在北京市郊区当日平均温度20℃时,棉田开始发病,24—28℃时,发病最烈,低于24℃或高于28℃时,病势减轻。相对湿度在80%以上,发病严重。棉花从苗期到吐絮期均能受其侵染为害,以蕾期受害最重,发病率达20.9—60.6%。防治棉花枯萎病应采取以种植抗病品种为主的综合防治措施。1973—74年,鉴定出陕721品种属高抗类型,蕾期发病率2.5—8.9%,病情指数31.5—35.4;药剂防治采用杀线虫剂滴滴混剂和杀菌剂多菌灵按10:2作土壤处理,蕾期防效可达85.2—100%,比单施杀菌剂或杀线虫剂防效提高20—30%,与小麦、玉米、水稻轮作3—4年,病害可减轻95%以上,病叶、病秆经高温(煮沸后再煮半小时以上)处理,病菌能被杀死。经处理的病叶喂猪,猪粪不带菌。无病土育苗移栽,发病率21.4%,直播棉田发病率63.3%。
Cotton blight in the suburbs of Beijing the average daily temperature of 20 ℃, the cotton began to attack, 24-28 ℃, the incidence of the most intense, below 24 ℃ or above 28 ℃, the disease lessened. Relative humidity above 80%, the incidence is serious. Cotton from the seedling to bolting floc can be affected by its infection, the most affected by the bud stage, the incidence rate of 20.9-60.6%. Prevention and control of cotton blight should be taken to plant resistant varieties of integrated control measures. In 1973-74, Shaanxi 721 cultivars were identified as high resistance type with the incidence rate of 2.5-8.9% in bud stage and the disease index of 31.5-35.4. The medicament was treated with nematicide and mixed fungicide and carbendazim according to 10: 2 For soil treatment, bud control effect of up to 85.2-100%, than the single fungicide or nematicide control effect increased by 20-30%, and wheat, corn, rice rotation 3-4 years, the disease can be reduced by more than 95% Sick leaves, stalks by the high temperature (boil and cook more than half an hour) treatment, bacteria can be killed. Treated diseased leaves fed pigs, pig manure without bacteria. Seedlings without disease transplanting, the incidence of 21.4%, the incidence of direct-fed cotton 63.3%.