Abstract:

Based on the monitor system on occurrence of brown planthopper（Nilapavata lugens-Stal）in late rice fields in Tiantai county of Zheijing province from 1969 to 2009 years, long-term movement cycles of brown planthopper were determined. The main factors affected on cyclical changes of brown planthopper populations were analyzed in the paper. The polynomial function model related to the amount changes of the insect populations was created by the formular: Y (t) = C0 + C1 * X + C2 * X2 + C3 * X3 +...+ C15* X15, X = (1,2,3, ……, n), and the time series ARIMA model: Y (t + l) = 0.0659 +0.0616851 Z (t + l-2) + e (t + l) +0.3802611 e (t + l-1) was also postulated，Application of this modelfor back-tested, consistent rate of 98.6%, with high accuracy .It is predicted from the models that high occurrence of brown planthopper will stay in a period in the future. It is suggested that we should increase prevention and control efforts in order to ensure safety in our rice production.