Establishing forecasting model specific to Algedonia coclesalis Watker in Anji, Zhejiang*

摘要

Phyllostachys pubescens Mazel is an important economic plant in Zhejiang Province which can provide both bamboo for industry raw materials and edible bamboo shoot. In recent decades, planting area of P. pubescens increases very fast and P. pubescens becomes the most important species for forestry industrial development. On the other hand, however, with the continual expansion of planting area of P. pubescens, the damage caused by insects like Algedonia coclesalis Watker is more and more serious, resulting in great loss in economy. In order to predict the occurrence of A. colesalis and control it in time, we collected the historical data of A. Coclesalis in Anji, Zhejiang from 1998 to 2008 and, analyzed the most important factors affecting the results of prediction. The analyzing results showed that factors affecting the accuracy of prediction includes the daily mean number of first- and second- instar larvae, daily mean temperature in November, daily mean rainfall in the middle-ten days of March, the middle-ten days of May and the first-ten days of June and the daily mean humidity in the last-ten days of March. The established forecasting model was as follows: Y=-48.74903+1.09280X_s+1.58167X_7+0,00768X_(19)+0.67192X_(25)+0.87988X_(33)+0.14832X_(36)+0.02336X_(42) The formula was tested by goodness of fit and back-tested with data of 2007 and 2008 respectively and the results were fine with high fitness.