柑桔木虱产卵寄主特征化合物的嗅觉识别研究

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a most destructive pest of citrus production worldwide as the merely vector of “Candidatus Liberibacter”species that cause huanglongbing (citrus greening disease). The behavioral manipulation of phytophagous insects is a novel effective approach to control the insect-borne disease. The female psyllids have the properties that they deposit eggs uniquekly on young tissues. The previous research project (31071712) and some research suggests that the recognition of oviposition site are mediated by the complex of volatile compounds (linalool and diterpinene). It is speculated that adult psyllids are able to recognize volatile complex via their olfactory system. The mechanism of olfactory recognition for single semiochemical has been well elucidated, while the olfactory interception for complex semiochemicals are remained unknown. This project employs RNA-seq, microarrays, RNAi,TALENs, neurophysiology and olfactory behavioral assays to carry out functional dissection of olfactory gene in oviposition mediators recognition. The whole mount fluorescence in situ hybridization (WM-FISH) and fluorescence immunohistochemistry (WM-FIHC) will be adopted to investigate the sensilla co-expression of OBPs or CSPs and ORs for the determination of gene functions in the olfactory system of citrus psylld. The aims of this project are to illustrate the possible mechanism of oviposition volatiles recognition template and to identify the corresponding candidate molecular targets for the development of safer and effective insect attractants so to provide theoretical basis of oviposition behavioral control of citrus psyllid.

柑桔木虱是毁灭性病害柑桔黄龙病的唯一传播媒介，而行为调控是控制虫媒病害的有效新途径。柑桔木虱雌成虫具有选择寄主植物幼芽产卵的特性。前一项目（31071712）和已有研究表明，介导柑桔木虱产卵寄主的特征挥发物为芳樟醇（linalool）和萜品烯（terpinene）,且单一化合物不具介导活性，推测柑桔木虱雌成虫嗅觉感受系统具有识别复合介导化合物的功能。目前昆虫对单一化合物的嗅觉识别机制已有较深入研究，但对复合化合物的嗅觉识别研究尚属空白。本项目拟通过对柑桔木虱的比较转录测序，鉴定出重要的嗅觉感受基因（OBPs、ORs/Orco和IRs），筛选和验证参与产卵介导相关的候选靶标基因功能，阐明柑桔木虱产卵寄主介导化合物的嗅觉识别机制，为柑桔木虱的行为调控提供理论依据。项目对解决昆虫的复合信息化合物嗅觉感受机制科学问题具有重要理论意义，对建立高效的产卵引诱化合物配体-受体筛选模型具有重要实用价值。

柑桔木虱是毁灭性病害柑桔黄龙病的唯一传播媒介，而行为调控是控制虫媒病害的有效新途径。柑桔木虱雌成虫具有选择寄主植物幼芽产卵的专性特征。本项目前期研究表明，介导柑桔木虱产卵寄主的特征挥发物为芳樟醇（linalool）和萜品烯（terpinene）,且单一化合物不具介导活性，推测柑桔木虱雌成虫嗅觉感受系统具有识别复合介导化合物的功能。目前昆虫对单一化合物的嗅觉识别机制已有较深入研究。本项目通过对柑桔木虱的比较转录测序，鉴定出了重要的嗅觉感受基因（OBPs、ORs/Orco和IRs），其中OPS基因9个、CSP基因12个、OR基因57个、IR基因35个，筛选和验证了参与产卵介导相关的候选靶标基因功能，阐明了 柑桔木虱产卵寄主介导模式是以萜类化合物为主的挥发物量变介导，而其识别是以触虫OBP1和OBP6介导的嗅觉识别机制。本研究结果为柑桔木虱的行为调控提供理论依据，对解决昆虫的复合信息化合物嗅觉感受机制科学问题具有重要的理论意义，对建立高效的产卵引诱化合物配体-受体筛选模型具有重要实用价值。本项目已发表SCI学术论文13篇，其中3篇为中科院农业与生物类1区学术期刊论文，申请国家发明专利1项，培养毕业博士生3名、在读博士生1名、毕业硕士生2名，与美国亚历山那州立大学建立了良好的昆虫行为神经生物学合作关系，共同发表SCI学术论文1篇。