中文摘要：

光肩星天牛Anoplophora glabripennis（Motsch.）是我国西北及华北地区危害杨树、柳树等树种的主要蛀干害虫,较难防治。花绒寄甲Dastarcus helophoroides（Fairmaire）是光肩星天牛等林木蛀干害虫的重要天敌昆虫。我国近几年来已开始广泛利用花绒寄甲对光肩星天牛进行生物防治,但由于天敌与寄主的生活史均较长,导致生物防治效果的评价并不理想。为了准确评价花绒寄甲对光肩星天牛的生物防治效果,在西安市未央区选择光肩星天牛危害严重的地区,分别设立花绒寄甲成虫释放区和2个不同距离的对照区作为样地,对样地内受害垂柳Salixbabylonica L.分别用油漆编号进行标记,在天敌释放前后开展了连续3年的跟踪调查。天敌于2009年5月30日释放。结果表明：在天敌释放后的第3年,天敌释放区和紧邻的对照1区的光肩星天牛的危害明显降低,株平均排粪孔数分别从释放前的4.63孔/株和5.06孔/株降到了0.93孔/株和0.87孔/株。光肩星天牛在对照2区的危害仍然严重,第3年的株平均排粪孔数为7.41孔/株,与释放前的7.68孔/株没有显著差异（P〉0.05）。结果说明花绒寄甲对光肩星天牛有较好的控制效果和应用前景。最后以本研究为例,对野外林木蛀干天牛害虫的生物防治效果评价方法进行了讨论,认为对于生活史较长的林木害虫与天敌昆虫,实施长期、定点的系统调查,才能得到令人信服的评价结果。

英文摘要：

Anoplophora glabripennis（Motsch.） is a main wood borer of willow,poplar and other deciduous hardwood trees in the northwestern China and North China.It is difficult to control this insect pest.Dastarcus helophoroides（Fairmaire） is an important parasitoid of A.glabripennis and other cerambycids,and it has been used as a biological agent to control A.glabripennis in recent years in China.However,due to long life-span of D.helophoroides and its hosts,the evaluation of biological control effect of D.helophoroides remains a challenge.In order to appropriately evaluate the biological control effect of A.glabripennis by D.helophoroides,field experiments of three consecutive years were carried out to investigate the control effect after releasing the parasitoid.The sample area was located in Weiyang District,Xi’an City,northwestern China,where Salix babylonica L.was seriously infested with A.glabripennis.The parasitoid release site and two control sites were selected in this area,of which one control site（control site 1） was adjacent with the parasitoid release site,the other control site labeled as control site 2 was 1.5 km away from control site 1.All trees in the sample sites were painted and marked with numbers,so they could be continuously investigated in the following years.D.helophoroides adults were released in the releasing site on May 30,2009.The results showed that the infested rates of A.glabripennis decreased both in the parasitoid release site and in the neighboring control site（control site 1） in the 3rd year.The average numbers of larval frass extruded hole per tree were decreased from 4.63 holes per tree and 5.06 holes per tree,respectively,in 2009 to 0.93 holes per tree and 0.87 holes per tree,respectively,in 2011.The infested rates of A.glabripennis in control site 2 were not significantly different between the first year（2009） and the third year（2011）（P〉0.05）,and the average number of frass holes per tree was 7.41 holes per tree in 2009 and 7.68 holes per tree in 2011,r