不同时期美国白蛾蛹的死亡率研究

通过对聊城地区美国白蛾越冬代和第一代蛹进行死亡率、寄生率、性别比例的调查统计,研究了美国白蛾Hlyphantria cunea(Drury)的发生危害程度与不同时期蛹死亡率之间的关系.结果表明:2011年越冬蛹的死亡率比2010年上升27.1%、寄生率上升6%,雌雄性别比例由1.22下降至0.89,主要的寄生性昆虫天敌有舞毒蛾黑瘤姬蜂Coccygomimus disparis(Viereck)及两种未鉴定的昆虫,分别隶属于姬小蜂科和蝇科,并以舞毒蛾黑瘤姬蜂为优势种;2011年第一代蛹死亡率较越冬代低41%,未发现寄生天敌.分析认为美国白蛾有逐步被本地生态系统同化现象,可能与天敌数量种类增多、生态系统生态补偿机制等有关.

Mortality Study of Hyphantria cunea Pupae in Different Generations

Relationships between the occurrence and mortality of Hyphantria cunea pupae in different generations was studied by investigating the mortality,sex and parasitic ratios.Results showed that the mortality of overwinter pupae in 2011 years increased 29.1%,and parasitic ratios increased 6% compared with 2010 years,however,the sex ratio of female to male decreased greatly from 1.22 to 0.89.There were three parasitic insects was observed,in which the main one is Coccygomimus disparis（Viereck）,but the other two have not been identified,which belongs to EuloPhidae and Muscidae,respectively.Results also showed that the pupae mortality of first generation was 41% lower than the overwinter pupae in 2011,and no natural enemies of insects was founded.Data indicate that H.cunea was somehow naturalized by the local ecosystem,which through the improvement of parasitic organism or other ecological compensations.