冀南棉区五代棉铃虫大发生及原因分析

Outbreak of the Fifth Generation of Cotton Bollworm in the Southern Cotton Area of Hebei Province and Its Reason Analysis

棉铃虫在河北省邯郸市1a通常发生4个完整世代。1994年5代棉铃虫在邯郸市严重发生，且多数幼虫能够入土化蛹，完成世代发育，历史罕见。本文简要报道了5代棉铃虫发生概况及特点，并以上源基教、气候条件，食料因素及天敌因子等4个方面分析了5代棉铃虫大发生的原因。

The cotton bollworm, Heliothis armigera (Hubner ), usually occurs fourcomplete generations in Handan cotton Area of Hebei province in a year' But it took placefive complete generations in 1994 and the fifth generation broke out and most of the fifthgeneration Larvae were capable of developing to pupa stage to complete the generation.The present paper reports some characteristics of outbreak of the fifth generation, andgives its reason analysis from residual Larvae,clamate,food and natural enemies,etc.