Speciation in sexually deceptive orchids

奥弗莱斯兰花模仿雌性昆虫的性信息素，从而吸引雄性昆虫授粉。花的气味受到授粉者的选择性影响，而物种形成可能是由花香的变化驱动的。本研究的目的是探讨杂交和渗入在性欺骗兰花的物种形成和辐射过程中所起的作用。在比较的方法中，我们将调查马略卡岛和撒丁岛上的O.fusca群的杂交群和共生的Ofreys分类群。我们将使用高度可变的标记进行分子分析，并结合对杂交群体和亲本物种的形态测量来划分物种，并为我们提供关于杂交植物与其亲本物种的遗传关系(杂交状态、导入)的信息。其次，我们将用杂交种和亲本种的拉贝拉提取物进行昆虫嗅觉反应的气相色谱和触角电联合记录(GC-EAD)。第三，用气相色谱-质谱仪(GC-MS)对GC-EAD活性物质进行鉴定，并将杂交花束与亲本产生的气味花束进行比较。第四，行为实验将显示单花对两个亲本物种的传粉者的吸引力。我们将能够使用单个植物的花朵进行化学分析和形态测量，并将植物组织用于分子分析。通过对基因和表型变异(气味、形态)的最终比较，我们将深入了解青海野生稻所研究的类群中的杂交、渐渗和物种形成过程。

Ophrys orchids mimic the sex pheromone of female insects and thereby attract males for pollination. The scent of the flowers is selectively influenced by the pollinators and speciation is probably driven by changes in floral odour. The objective of this study is to investigate the role of hybridisation and introgression in processes of speciation and radiation in sexually deceptive orchids of the genus Ophrys. In a comparative approach, we will investigate hybrid swarms and sympatrically occurring Ophrys taxa of the O. fusca group on Majorca and Sardinia. We will perform molecular analyses using highly variable markers in combination with morphometric measurements on hybrid swarms and of the parental species to delimit species and provide us with information on the genetic relationship of hybrid plants to their parental species (hybrid status, introression). Second, we will perform combined gas chromatography and electroantennogram recording of insect olfactory responses (GC-EAD) with labella extracts of hybrids and parental species. Third, the GC-EAD active compounds will be identified by gas chromatography - mass spectrometry (GC-MS) and the bouquets of hybrids compared with the odour bouquets produced by the parental species. Fourth, behavioural experiments will show attractiveness of single flowers for pollinators of both parent species. We will be able to use from individual plants flowers for chemical analyses and morphometric measurement and plant tissue for molecular analyses. A final comparison of genotype and phenotype variation (odour, morphology) will give us insight in processes of hybridisation, introgression and speciation within the investigated taxa of the O. fusca group.