花绒寄甲寄主定位信息化学物质的分离鉴定

Identification Volatile Compounds Involved in Host Location by Dastarcus helophoroides

花绒寄甲Dastarcus helophoroides是天牛类害虫重要的天敌昆虫,通过释放花绒寄甲成虫或卵可以有效地控制包括松褐天牛Monochamus alternatus等天牛类蛀干性害虫。嗅觉在寄生性天敌的寄主搜寻或定位过程中起着重要的作用,但花绒寄甲如何在复杂外界环境中利用哪些信号物质准确地搜寻到寄主松褐天牛目前还不明确。为此,本文测定了花绒寄甲对几种气味源的行为反应,对相关的化学物质进行了分离鉴定。结果发现,花绒寄甲对不同气味源的行为反应不同,趋于选择松褐天牛为害后的马尾松木段、松褐天牛幼虫及其虫粪。通过GC−MS分离鉴定出了18种化合物,通过因素扣除的方法分析发现,化合物D−柠檬烯和长叶烯可能是花绒寄甲在寄主定位过程中的信息化学物质。

Dastarcus helophoroides is an important natural parasitoid enemy,which has been released to control long-horned beetles including Monochamus altelnatus.It has been reported that olfactory play a key role in the host location of natural enemies,while chemical cues for host location by D.helophoroides is not clear now.In this study,behavioral responses of D.helophoroides to several odor sources were tested by Y-tube olfactometer,and volatile compounds involved in host location by D.helophoroides were identified by GC−MS.The results showed that D.helophoroides adults showing the preferences to the larvae and fecula of M.altelnatus.Total of 18 headspace compounds were identified from different odor sources,and two compounds D-limonene and longifolene might play the key role in the process of host location of D.helophoroides.