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粘虫一代幼虫是小麦生长中、后期的主要害虫。我县常年发生面积30万亩,大发生年份在40万亩以上。据实验测定,一般年份小麦减产3—5％,大发生年份减产10—15%,每年损失小麦750万斤左右,对生产威胁很大。为了提高对粘虫一代幼虫的预测预报效果,更好地指导防治,我们在历年经验测报的基础上,用病虫害数理统计的符号相关选择法,对我站14年来积累的与发生程度有关的主要因素加以判断。初步分析得出,影
The armyworm larvae are the major pests in the late and late stages of wheat growth. Occurred in our county area of 30 million mu perennial, occurred in 40 million mu or more year. According to the experiment, wheat yield is reduced by 3-5% in the general year, 10-15% in the big year, and 7.5 million kg in wheat is lost each year, threatening the production. In order to improve the prediction and control of the armyworm larvae and to better guide the prevention and treatment, based on the historical reports of past experiences, we use the symbolic correlation selection method of mathematical statistics of pests and diseases to analyze the degree of occurrence Factors to be judged. Preliminary analysis drawn, shadow