Long & Medium Term Research: Evolutionary Genetics of Host Plant Choice in a Willow Leaf Beetle

中长期研究：柳叶甲虫寄主植物选择的进化遗传学。该奖项是在国外卓越中心长期和中期研究计划下推荐的。该项目旨在使美国科学家和工程师能够在国外被证明卓越的研究机构进行长期研究。该奖项为开展联合研究以及利用国外独特或互补的设施、专业知识和实验条件提供了机会。这笔奖金将支持Nathan Rank博士对比利时和瑞士进行为期12个月的访问，与布鲁塞尔自由大学的Jacques Pasteels博士和巴塞尔大学动物学研究所的Martine rowel - rahier博士合作，研究“柳叶甲虫寄主植物选择的进化遗传学”。为了更好地了解昆虫寄主转移的进化后果，首席研究员建议完成一项研究，研究寄主使用的区域差异与柳叶甲虫遗传差异之间的关系。柳叶甲虫是一种分布在欧亚大陆的柳叶甲虫（鞘翅目：柳叶甲虫科），已知其寄主存在区域差异。柳甲虫总体上具有高度细分的种群结构，即使在很小的空间尺度上也具有可测量的遗传分化。由于黄颡鱼具有偏好的区域差异和细分的种群结构，将为本研究提供一个很好的模型。在他之前对北美柳叶甲虫种群结构的研究和Rowell-Rahier教授对P. vitellinae寄主植物使用的区域差异的研究的基础上，首席研究员将提出以下问题：1)昆虫如何进化出对新寄主植物物种的偏好？2)昆虫在完成寄主转换后是否会形成遗传上不同的寄主种族？为了回答这些问题，他将：1)使用电泳标记来测量卵黄假单胞虫的种群结构，并确定种群是否沿着宿主物种线分化；2)对寄主植物偏好进行遗传分析。实验方案将包括：1)量化偏好群体内的遗传变异；2)通过显示偏好区域差异的群体杂交来确定偏好的遗传模式。因为首席研究员将使用相同的卵黄疟原虫种群进行电致性研究和遗传分析，他将能够将宿主使用的变化与遗传分化模式直接联系起来。

Long & Medium-Term Research: Evolutionary Genetics of Host Plant Choice in a Willow Leaf Beetle. This award recommendation is made under the Program for Long & Medium-Term Research at Foreign Centers of Excellence. The program seeks to enable U.S. scientists and engineers to conduct long-term research abroad at research institutions of proven excellence. Awards provide opportunities for the conduct of joint research, and the use of unique or compli- mentary facilities, expertise and experimental conditions in foreign countries. This award will support a twelve-month visit by Dr. Nathan Rank to both Belgium and Switzerland, to work with Dr. Jacques Pasteels, Universit> Libre de Bruxelles, and Dr. Martine Rowell-Rahier, Zoologisches Institut der Universitaet Basel, on "Evolutionary Genetics of Host Plant Choice in a Willow Leaf Beetle." In order better to understand the evolutionary consequences of host shifts in insects, the principal investigator proposes to complete a study of the relationship between regional variation in host use and genetic divergence in a willow leaf beetle, Phratora vitellinae (Coleoptera: Chrysomelidae), common throughout Eurasia, which is known to vary hosts regionally. Willow beetles in general have a highly subdivided population structure, with measurable genetic differentiation at even small spatial scales. Since P. vitellinae has the regional variation in preference and a subdivision population structure, it will provide an excellent model for this study. Building on his previous work on the population structure of a North American willow leaf beetle and Prof. Rowell-Rahier's research on regional variation in P. vitellinae's host plant use, the principal investigator will ask: 1) How do insects evolve preferences for new host plant species?, and 2) Do insects form genetically differen- tiated host races when they accomplish a host shift? To answer these, he will: 1) Use electrophoretic markers to measure P. vitellinae's population structure and to determine whether populations are differentiated along host species lines; and 2) Conduct a genetic analysis of host plant preferences. The experimental protocol will include 1) quantification of genetic variation within populations in preference and 2) determination of the mode of inheritance of preference by crossing populations which show regional variation in preference. Because the principal investigator will use the same P. vitellinae populations for the electrop- horetic study and the genetic analysis, he will be able to relate variations in host use directly with patterns of genetic differentiation.