棕榈蓟马对瓜类作物取食定位机理研究

Thrips palmi Karny (Thysanoptera, Thripidae) is a polyphagous，destructive pest of Cucurbitaceae in Guangxi.It is small and covert and propagates quickly .It is also a vector of alien tospoviruses,and it has orientation and feeding selectable character on Cucurbitaceae.In this subject,the mechanism of Thrips palmi's feeding and orientation on melon crops will be studied systematically in theory for control of it from start.Firstly，the number of Thrips palmi occurs in different melons and varieties will be surveyed by five sampling method.Secondly,the influence of the melon crops volatiles ,colour and shape to the oritation from far will be researched by some methods, in which some instruments such as：the Head Space Sampling collecting apparatus，Gas Chromatography-Mass Spectrometre(GC-MS), Sticky Traps, olfactometer will be used. Thirdly,the influence of the physical structures,nutritional ingredients, secondary metabolites(cucurbitacin and flavones) consists in the melon crops to the oritation at short ranges will be researched by some methods,including bradford method,the anthrone method, Soxhletextraction, paraffin section and instrument analysis methods and so on. Finally, the key chemical factor which influences the feeding and orientation of Thrips pamli will be assayed by the life table method. And the synthesized route of the key factor will be extrapolated. The study lets us understand the fundamental reason for Thrips pamli's feeding and orientation on the melon crops. The research results can provide the groundwork for the mechanism study on induced defense against melon crops.It can also lay a solid foundation for integrated management on Thrips palmi.

棕榈蓟马是广西地区常发的一种重要害虫，在取食瓜类作物时具有专向选择性。为从理论上探索其取食定位机理，本项目拟在棕榈蓟马瓜类作物上取食定位调查的基础上，进一步采用顶空气体收集法和气-质联用法、粘虫板法和嗅觉仪法等研究寄主气味、颜色、形状对蓟马远距离定向的影响；采用考马斯亮兰法、蒽酮法、索氏提取法、石蜡切片法、仪器检测法等研究寄主植物的物理结构、营养成分、葫芦素、黄酮类化合物对棕榈蓟马近距离取食定位的影响；最后，采用生命表方法分析影响棕榈蓟马对瓜类植物取食定位的关键化学因子，并探讨该因子在瓜类作物体内的产生途径。本项目的研究结果可为研究瓜类作物诱导防御机理打下基础，也可为棕榈蓟马的综合治理方案的制定提供可靠的理论依据。

本项目通过调查棕榈蓟马在不同瓜类作物不同品种上的为害数量、测定其中的营养成分差异和次生代谢成分差异，确定黄瓜为棕榈蓟马为害差异较大、营养成分和次生代谢成分均有差异的作物种类。进一步采用溶剂提取法收集了不同品种不同部位叶片挥发物，采用气-质联用法分析了其中的挥发性成分，发现黄瓜不同部位叶片中都含有大量的烷烃类挥发物，其含量达到总挥发物的90%左右，说明烷烃类可能起到部分引导棕榈蓟马定向的作用；测定出蓝色光线对蓟马远距离定向也有引导作用；采用考马斯亮兰法、蒽酮法、临时切片法、仪器检测法等研究寄主植物的物理结构、营养成分、葫芦素、黄酮类化合物对棕榈蓟马近距离取食定位的影响，发现营养成分含量高会诱导棕榈蓟马的取食，次生代谢成分的作用还不明确。本项目的研究结果可为棕榈蓟马的综合治理方案的制定提供可靠的理论依据。