【目的】 弗氏窄吉丁Agrilus fleischeri Obenberger是我国东北地区新发现的一种杨树蛀干害虫。为探讨该害虫的有效防治策略，指导生产上科学营林，我们调查研究了弗氏窄吉丁对本地杨树山杨Populus davidiana及外来引种杨树钻天杨Populus nigra var. italica的危害情况。【方法】 试验设置了钻天杨与山杨两块纯林样地，采用完全随机取样法于两样地内各选取20株样木进行环割以诱集弗氏窄吉丁。调查两树种的自然受害和人工胁迫后的受害情况，通过解剖感虫株分析虫口密度、死亡率及天敌种类。【结果】 钻天杨的自然受害株率（11.76 %）显著高于山杨（0），人工环割后钻天杨和山杨的受害株率分别为90 %和65 %，感虫的钻天杨和山杨平均虫口密度分别为61.95头/株和34.89头/株。钻天杨树上的卵孵化率（91.78 %）显著高于山杨（77.61 %）。弗氏窄吉丁幼虫在钻天杨树上的蛀道长度（48.68 cm）与山杨（29.59 cm）相比差异显著。对比两树种上的蛹室，发现其长度、宽度和深度差异不明显。分析比较弗氏窄吉丁成虫羽化孔在两树种上的分布，发现在钻天杨上主要分布在1~6 m的主干，山杨为1~3 m。此外，两样地中弗氏窄吉丁幼虫的生态位宽度也存在不同，钻天杨林中为0.53，山杨林中仅为0.32。【结论】 研究结果显示，相对于本地树种山杨而言，非本地的引种树种钻天杨更易感虫。研究结果可为生产上防治该害虫和受害林分的合理改造提供基础信息和科学依据。

 [Objectives]  Agrilus fleischeri Obenberger is a newly emerged wood borer of poplar trees, which has been becoming a destructive pest in Liaoning Province, northeast China recently. To develop effective management strategies of this beetle, and provide suggestions for reasonable matching tree species in reforestation process, we studied the damage of exotic species Populus nigra var. italica and native species P. davidiana. [Methods]  Two pure stands of P. nigra var. italica and P. davidiana were set up as field investigation sites. Twenty P. nigra var. italica and twenty P. davidiana trees were selected randomly and girdled in early spring of 2013 and 2014 respectively to attract A. fleischeri female adults for oviposition. Natural and stressed infestation rates of two species of poplar trees were surveyed in the field. Population densities, mortality and lethal factors of the beetle were investigated by dissecting infested host trees. [Results]  Results indicated that the natural infested percentages of P. nigra var. italica and P. davidiana were 11.76% and 0 with a significant difference, while 90% artificially stressed P. nigra var. italica and 65% stressed P. davidiana were infested by A. fleischeri after girdling. The average population densities of the pest were 61.95 larvae per tree on P. nigra var. italica and 34.89 larvae per tree on P. davidiana. Egg hatch rate on P. nigra var. italica (91.78%) was significantly higher than that on P. davidiana (77.61%). Larvae of A. fleischeri were mainly found in galleries with an average 48.68 cm in length on P. nigra var. italica and those were 29.59 cm on P. davidiana. The differences of pupal chambers on the two species of poplar trees were not significant in length, width and depth. Moreover, a vertical distribution model illustration of exit holes of A. fleischeri on the trunk was established, which revealed that exit holes mainly distributed in 1-6 m on P. nigra var. italica and 1-3 m on P. davidiana above ground. Difference of niche width of A. fleischeri larvae and their natural enemies also accounted for the different damage degrees. Niche width of A. fleischeri larvae were 0.53 and 0.32 on P. nigra var. italica and P. davidiana respectively. [Conclusion]  Exotic poplar species P. nigra var. italica is more vulnerable than native poplar P. davidiana. Our findings can provide information and scientific support for the management of the pest and rational reforestation in practice.