摘  要  【目的】 枸杞红瘿蚊Gephyraulus lycantha Jiao & Kolesik是枸杞上的一种重要害虫。为探讨其对枸杞属3种寄主植物的产卵选择差异，解析影响其寄主选择的信息化学物质。【方法】 采用选择和非选择性测定方法，观察枸杞红瘿蚊在宁夏枸杞、中华枸杞和黑果枸杞花蕾上的产卵选择性；通过Y型嗅觉仪，测定孕卵雌虫对这3种枸杞挥发物的行为选择偏好；运用动态顶空吸附法和气相色谱-质谱联用技术，分析影响枸杞红瘿蚊产卵选择的3种枸杞挥发物的成分差异。【结果】 宁夏枸杞为枸杞红瘿蚊最嗜好的寄主植物，孕卵雌虫对其幼嫩花蕾的产卵选择率和花蕾中的落卵量显著高于中华枸杞和黑果枸杞（P<0.05）。无论是与空白对照相比，还是3种枸杞挥发物相互比较，枸杞红瘿蚊孕卵雌虫对宁夏枸杞挥发物均具有显著的嗅觉选择偏好（P<0.05）。3种枸杞挥发物的种类和释放量存在一定差异，宁夏枸杞与中华枸杞挥发物的组分较为相似，均含有较高比例的酯类物质，而酚类化合物是中华枸杞的特有种类；黑果枸杞中的酯类物质含量很低，但酮类物质的含量极高。【结论】 3种寄主植物中宁夏枸杞是枸杞红瘿蚊最嗜好的寄主植物，不同枸杞花蕾挥发物中的特异性物质可能会引起枸杞红瘿蚊的选择行为差异。

Abstract  [Objectives]  To investigate the oviposition preferences of gall midge, Gephyraulus lycantha Jiao & Kolesik (Diptera: Cecidomyiidae), females with respect to three different Lycium spp. host plants, and thereby clarify the effect of semiochemicals on host selection. [Methods]  Oviposition preferences for three host plants, L. barbarum, L. chinense and L. ruthenicum, were determined in both choice and no-choice experiments. The preference of gravid females for specific volatiles emitted from these three different host plant species was measured in a Y-tube olfactometer under laboratory conditions. Dynamic headspace collection and gas chromatography-mass spectrometry were used to analyze differences in the composition of volatiles emitted from the three different host plant species. [Results]  L. barbarum was the preferred host species with a significantly (P<0.05) higher oviposition selection rate and number of eggs laid on the young flower buds of this species than on L. chinense or L. ruthenicum. The results of Y-tube olfactory experiments showed that females also significantly (P<0.05) preferred volatiles from bud-bearing branches of L. barbarum to those of the other two species. There were significant differences in the volatiles emitted from healthy flower buds of the three Lycium species. Volatile components of L. barbarum and L. chinense were relatively similar in that both contain a higher proportion of esters, whereas L. ruthenicum volatiles were low in esters and high in ketones. [Conclusion]  G. lycantha significantly preferred ovipositing on L. barbarum to L. chinense or L. ruthenicum. Differences in the volatiles emitted from flower buds of L. barbarum might be responsible for this preference.