舞毒蛾化蛹阶段自然控制作用初步调查

Investigation of natural control effect during prepupa and pupa development of Lymantria dispar

舞毒蛾是世界范围内的重要森林食叶害虫,取食多种阔叶和针叶树木。为了解舞毒蛾在我国危害较轻的原因,作者在林间设立样方,调查下树将要化蛹的舞毒蛾老熟幼虫的死亡率及致死因素,蛹的死亡率及致死因子。发现病毒是导致老熟幼虫死亡的主要因子,死亡率高达96.6%。蛹的致死因子较多,其中一种皮蠹取食导致的致死率较高,达到58%,舞毒蛾黑瘤姬蜂的致死率也较高。研究表明,舞毒蛾化蛹阶段致死因子及死亡率较高,可能是舞毒蛾发生危害较轻的原因之一。

Lymantria dispar（Lepidoptera： Lymantriidae） is a worldwide forest defoliator.It attacks hundreds of tree species including broad-leaved and coniferous trees.However,L.dispar is not a serious forest insect pest in China.In order to explain the reason why L.dispar could not cause serious damage to forest in China,authors investigated the mortality rate and related lethal factors during late-instar larvae and pupae development of gypsy moth.Results showed that virus was the main factor causing late-instar larvae death,and the mortality rate reached to 96.6% during the investigation period.There were several factors causing pupae death.Among these factors,one kind of carpet beetle（Coleopetera： Dermestidae） caused about 58% mortality rate of pupae.Coccygomimus disparis Viereck also had higher parasitism rate.These results indicated that there were many factors caused the death of late-instar larvae and pupae,which kept L.dispar in a low population density in China.