中文摘要：

对重大林业害虫美国白蛾 Hyphantria cunea（Drury）的重要寄生性天敌周氏啮小蜂Chouioia cunea Yang（膜翅目：姬小蜂科）一个Or83b直同源基因的cDNA全长序列CcOr1进行多角度的进化分析，为研究周氏啮小蜂嗅觉分子机制奠定基础。通过转录组测序的方法鉴定 CcOr1基因全长，并对该基因进行序列及进化分析。该基因长度为1428 bp，编码475个氨基酸；蛋白二级结构预测具脊椎动物G蛋白典型的七跨膜结构域。该基因较为保守，主要接受负选择压力。作为寄主广泛的寄生蜂，周氏啮小蜂与寄主单一的类群相比，其同义突变率较低，密码子偏好性较高。

英文摘要：

Objectives To investigate the olfactory molecular mechanism of Chouioia cunea Yang （Hymenoptera：Eulophidae）. C. cunea is a significant parasitic natural enemy of the fall webworm Hyphantria cunea （Drury）. We here provide the first description of the full-length cDNA of the Or83b orthologous gene of C. cune, named CcOr1. [Methods] We identified the full-length of CcOr1 and analyzed its gene sequence and likely evolution. [Results] Sequencing showed that CcOr1 is 1 482 bp in length, encoding 475 amino acid residues. The secondary structure of CcOr1 is similar to the G protein-coupled receptors of vertebrates with seven transmembrane regions.[Conclusion] The CcOr1 gene is highly conserved relative to other insects and appears to be primarily negatively selected. As a parasitic wasp with a wide range of hosts, C. cunea has lower synonymous substitutions and higher codon usage bias compared with host-specific wasps.