甘薯蚁象在重庆的发生调查及成灾原因初探

为探明甘薯蚁象在重庆地区的发生规律，2011—2012 年对甘薯蚁象在重庆巫山的发生情况进行调查。甘薯蚁象在重庆地区主要以幼虫、蛹、成虫在窖藏薯块和田间遗留的薯块中越冬。甘薯蚁象在育秧田发生集中，危害严重。育秧期是防治的关键时期。玉米套种田发生危害较轻。成虫发生高峰期在8 月上旬—10 月上旬，没有明显的世代数。甘薯蚁象繁殖力强、能够安全越冬和不间断食物链是重庆地区甘薯蚁象成灾的主要原因。

Survey on Occurrence of the sweetpotato weevil (Cylas formicarius) and preliminary study on its outbreak in Chongqing

The occurrence of sweetpotato weevil Cylas formicarius in Chongqing was investigated during 2011 and 2012 in Wushan county, Chongqing for understanding the occurrence characteristics. The larvae, pupae and adults of sweetpotato weevil in tuberous root could overwinter in storage or in open field. The sweetpotato weevil occurred seriously in nursery bed. Therefore, the control of sweetpotato weevil in nursery bed was very important. The damage of sweetpotato weevil was more serious in the field of monoplanting sweetpotato than sweetpotato interplanting with corn. The peak period of adult occurrence was from beginning of August to October. The different generation of weevils was not distinct. The causes of sweetpotato weevil outbreak were its high fecundity, optimum temperature for overwinter and sustain food source in Chongqing area.