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通过对２０多年的调查资料统计分析发现，棉田棉铃虫的发生程度受其主要发生季节降雨量的影响极大，尤其是６～８月的降雨量是该虫发生程度的决定因素。统计资料表明，凡３个月累计雨量达５００ｍｍ以上的年份，该虫发生都轻；３个月累计雨量在４００ｍｍ以下的年份发生严重。经统计相关分析，棉铃虫年度发生程度与６～８月雨量负相关达极显著标准（ｒ＝｜－０．８５８｜＞ｒ＿（０．００１）＝０．６７８７）；四代发生程度与６～８月雨量负相关也极显著（ｒ＝－０．８７２３）；三代发生程度、四代发生程度与７月降雨量负相关也达极显著标准，相关系数分别为－０．７９２和－０．６９８５。
Through statistical analysis of survey data of more than 20 years, it is found that the occurrence degree of cotton bollworm in cotton field is greatly affected by its main seasonal rainfall, especially the rainfall from June to August is the determinant of the occurrence of the insect. Statistical data show that the occurrence of all three months of rainfall is more than 500mm above the light, the incidence of light; 3 months cumulative rainfall below 400mm in the years serious. According to the statistical analysis, the annual incidence of cotton bollworm and the rainfall from June to August reached a very significant negative correlation (r = | -0.858 |> r_ (0.001) = 0.6787) The correlation between the monthly rainfall and August rainfall was also significant (r = -0.8723). The incidence of three generations, the occurrence of the fourth generation and the rainfall in July also reached the significant standard with the correlation coefficient of -0.792 and -0 .6985.