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通过历年资料分析，气象因素对棉铃虫发生的影响很大，其中以雨日和日照时数与四代的相关系数最大。通径分析表明，影响四代发生量的直接因素则是三代卵量、６至７月间的日照时数和平均气温，直接通径系数依次达０．５３０８、０．４４０５和０．２７２４，降雨和雨日对四代的直接作用很小，但它们通过三代对四代的间接作用却比较大，间接通径系数分别达－０．３０４８和－０．３２５７。根据有关气象因子及三代发生实况组建的一组预测模式在四代的发生量预测中，取得了较为满意的效果
Through the analysis of historical data, meteorological factors have a great influence on the occurrence of cotton bollworm, and the correlation coefficient between rainy days and sunshine hours and the fourth generation is the largest. Path analysis showed that the direct factors influencing the occurrence of the fourth generation were the number of three generations of eggs, the sunshine duration and the average temperature from June to July, the direct path coefficients were 0.5308, 0.4405 and 0.2724, The direct effects of rainfall and rainy days on the fourth generation are small, but their indirect effects through the third generation to the fourth generation are relatively large with indirect path coefficients of -0.3048 and -0.3257, respectively. According to the meteorological factors and the live generation of three generations of a set of prediction models in the generation of the fourth generation forecast, and achieved satisfactory results