寄主识别利它素诱导野蚕黑卵蜂寄生马尾松毛虫的研究

A new host based on the host-recognition kairomone of Telenomus theophila (Hymenoptera:Scelionidae)--Dendrolimus punctatus

利用野蚕黑卵蜂寄主识别利它素,成功诱使野蚕黑卵蜂寄生非寄主马尾松毛虫卵并羽化出下一代,使野蚕黑卵蜂在仅能寄生野桑蚕和桑蚕的基础上增加了一种人工新寄主———马尾松毛虫卵。研究表明,野蚕黑卵蜂对涂布有稀释8倍利它素非寄主马尾松毛虫卵的寄生百分数为92.1%,与寄生桑蚕卵的96.6%相比没有明显差异;子代的平均发育历期为20.42d,与桑蚕卵内的发育历期差异显著且长2d左右。通过对三因素组合试验的结果分析表明,识别利它素的不同浓度、非寄主的不同来源和野蚕黑卵蜂的不同寄生经验对野蚕黑卵蜂的寄生行为均有显著影响。采用无寄生经验野蚕黑卵蜂和解剖自马尾松毛虫雌蛾卵巢的未产出卵并在表面涂稀释4～128倍识别利它素是野蚕黑卵蜂成功寄生非寄主马尾松毛虫卵的最佳方案。

Through use of the host recognition kairomone of Telenomus theophila Wu et Chen,the parasitoid T.theophila was induced to oviposit in a nonhost of Dendrolimus punctatus Walker successfully, which had been a new host of T.theophila besides the original hosts of Theophila mandarina and Bombyx mori.The result showed the parasitism ratio of T.theophila in the nonhost being coated with the kairomone was 92.1%,having no significant difference with that in the unnatural host of B.mori.The average duration of life cycle of T.theophila's filial generation in the nonhost was 20.42 days,which was about 2 days longer than that in B.mori.Further studys showed three factors had influenced T.theophila's parasitism, they were the varied concentrations of the kairomone,the parasitoid's parasitism experiences,and the differences of the nonhost eggs.On analysing the effects of them,we concluded that the best way of T.theophila's parasitism in the nonhost was to take use of inexperenienced T.theophila,and anatomized eggs from female D.punctatus adults' ovary, which should be coated with kairomones being diluted from 4 to 128 times.