获取番茄褪绿病毒的烟粉虱对寄主选择行为改变的机制

The interaction between plant virus and its vector is the frontier research topic in the research areas of vector biology and ecology. Our previous study has revealed that Tomato chlorosis virus (ToCV)-viruliferous whitefly (Bemisia tabaci MED species) preferred to the healthy tomato plant, which may be closely associated with the rapid spread of this virus in the field. The project will focus on the scientific issue on the mechanism underlying the changes of host selection behavior of ToCV-viruliferous whitefly, and will use the methods in behavior, chemical ecology, and molecular biology to explore the issues as follows. 1) Determine the difference of the volatile between the healthy and ToCV-infected tomato plant, and reveal the effects of the changes of volatile on the host location behavior of the whitefly; 2) Analyze the changes of feeding behavior of the whitefly on the virus-infected plant using EPG technique, and reveal the effects of the nutrition metabolism and defense response of the ToCV-infected tomato plant on the feeding behavior; 3) Analyze the response of BtabCSP in whitefly to the volatiles changed, which provide the physiological basis of the behavior changes of the viruliferous whitefly. The goal of the project is to reveal the mechanism underlying the changes of host selection behavior of ToCV-viruliferous whitefly. The results will be helpful to reveal the epidemiology of ToCV in the field, to provide insights into the interactions between plant virus-vector insect-plant, and to develop novel ways to control agricultural pest.

植物病毒与媒介昆虫的互作是媒介生物学和生态学领域交叉性前沿课题。前期研究发现：烟粉虱MED隐种获毒番茄褪绿病毒（ToCV）后更偏嗜健康番茄植株，这可能是近年来ToCV在田间快速扩散的重要原因。围绕“获毒烟粉虱寄主选择行为变化的机制”这一科学问题，拟采用行为学、化学生态学和分子生物学的方法，以ToCV-烟粉虱-番茄为研究体系，重点研究：1）明确健康与病毒侵染植株挥发物差异，揭示挥发物变化对烟粉虱定位行为的影响；2）EPG技术解析烟粉虱对病毒侵染植株取食过程中的行为变化，揭示侵染植株营养代谢与防御反应对烟粉虱取食行为的影响；3）分析烟粉虱化学感受蛋白BtabCSP对组分或含量变化的植物挥发物的响应，揭示烟粉虱行为改变的生理基础。旨在系统揭示获毒烟粉虱寄主选择行为改变的机制。成果对揭示ToCV的田间流行机理，深化对病毒-昆虫-植物互作的认识以及拓展病虫害防控新途径具有重要理论意义和实践价值。

植物病毒与媒介昆虫的互作是媒介生物学和生态学领域交叉性前沿课题。前期研究发现：烟粉虱MED隐种获毒番茄褪绿病毒（ToCV）后更偏嗜健康番茄植株，这可能是近年来ToCV在田间快速扩散的重要原因。围绕“获毒烟粉虱寄主选择行为变化的机制”这一科学问题，采用行为学、化学生态学和分子生物学的方法，以ToCV-烟粉虱-植物为研究体系，研究了揭示ToCV侵染植株与健康植株挥发物对获毒烟粉虱寄主定向选择的影响；进一步比较ToCV侵染植株与健康植株挥发物的差异并分析变化组分对烟粉虱寄主定位的影响；研究ToCV对烟粉虱取食行为的影响，解析携毒ToCV对Q烟粉虱取食行为的修饰作用，揭示携毒对烟粉虱取食行为的影响；从ToCV侵染植物的营养代谢与防御途径揭示病毒影响烟粉虱行为的生化基础与分子机理；构建烟粉虱BtabCSP1的原核表达并纯化，分析烟粉虱重组蛋白BtabCSP1与气味配体的结合能力。结果研究显示：ToCV侵染植株（番茄）降低植株对烟粉虱具有吸引效应的挥发物乙基苯乙酮浓度，增加趋避性挥发物2,6-二叔丁基对甲基苯酚浓度；同时增强了烟粉虱对挥发物对乙基苯乙酮具有结合效应的化学感受蛋白OBP-17和CSP-1表达量。ToCV对烟粉虱化学感受蛋白与植物挥发物的双重调控效应有利于病毒的扩散。上述结果系统揭示了获毒烟粉虱寄主选择行为改变的机制，对揭示ToCV的田间流行机理，深化对病毒-昆虫-植物互作的认识以及拓展病虫害防控新途径具有重要理论意义和实践价值。