香梨优斑螟（Euzophera pyriella）属鳞翅目螟蛾科，是林果业重要的害虫之一，在新疆和甘肃广泛分布，以环塔里木特色林果主产区发生最重，主要寄主有梨、苹果、杏和枣等。幼虫蛀食果实和枝干韧皮部，化学防控困难，已成为绿色果品生产的主要障碍。针对显性致死昆虫不育技术在生物防控中的潜力和优势，结合新疆绿洲农业系统特点和前期转录组测序数据，项目拟进一步开展香梨优斑螟性别决定基因（Ep-Dsx）功能研究。首先通过基因克隆技术获得Ep-Dsx不同剪切异构体全长序列，并利用生物信息学方法分析基因蛋白质结构与功能；再通过RT-PCR技术研究Ep-Dsx基因在各虫态及组织内的表达特征；同时以RT-PCR、RNA-seq和观察比较法，研究该基因经RNAi有效调控后对两性发育特征的影响，及性别决定基因产物变化。研究结果将为确立香梨优斑螟性别决定模式奠定基础，为雌性不育品系构建和不育防控策略提供理论支持。

Euzophera pyriella (Lepidoptera: Pyralidae) is an influential pest of fruit tree, which widely distributes in Xinjiang and Gansu provinces, particularly in the main producing areas of forest and fruits around Tarim Basin. The main hosts of E. pyriella are pear, apple, apricot and jujube, etc. The larvae bores fruit and phloem of trunk or branches, it is extremely difficult for chemical prevention and control, and this pest has become a major obstacle to the green fruit production. With the potential and advantages of sterile technique of release of insects with dominant lethality (RIDL) in bio-control, and combining the characteristics of oasis agricultural systems and the previous transcriptome sequencing results, this project is intended to further research the functions of sex-determining key gene or doublesex (Ep-Dsx) gene of E. pyriella. Firstly through gene cloning technology, the different slicing isoforms with full-length sequences of Ep-Dsx gene will be obtained, and protein structure and function of Ep-Dsx gene will be analyzed by bioinformatics software; then by RT-PCR technique, the expression characteristics of Ep-Dsx gene will be compared in different instars and within reproductive organ tissue; and meanwhile using RT-PCR, RNA-seq and histochemical methods, the impact of Ep-Dsx gene after effective RNAi regulation on the development characteristics of the male and female, and on the differences of sex-determining gene products will be studied. These results will lay the foundation for research on the model of sex determination in E. pyriella, and will contribute to the Breeding of strains of female sterility and provide theoretical support for formulation of RIDL prevention and control strategies of E. pyriella.