湖南省棉铃虫发生规律和预测预报研究

湖南省棉铃虫1a发生5代，其中第二至四代为主害代。通过对湖南省近年棉铃虫的发生情况系统分析，提出气候变化、耕作制度改变、大区域连年大发生和天敌控制效应下降是湖南省棉铃虫加重为害的主要原因；成虫诱测技术中以黑光灯诱测较为简便易行；采用回归预测、期距预测可提前20d以上准确预报防治适期。

STUDY ON THE OCCURRENCE OF COTTON BOLLWORM AND ITS FORECAST IN HUNAN PROVINCE

Five generations of cotton bollworm occur in Hunan Province in a year and generation 2 to generation 5 are the main damaging generations. Based on the data of the occurrence of cotton bollworm in recent years, the main reasons of the more severe damage caused by cotton bollworm in Hunan Province were put forward. They were the change of the climate and culture system, severe occurrence in several consequent years in large areas and the decrease of the control effect by the nature enemies. Black light lamp trapping the cotton bollworm imagoes is more feasible than other trapping techniques. The forecasts of regression and period intervals can be made accurately for the suitable time of control 20 days advanced.