Collaborative Research: Relationships Among Gene Lineages, Morphology, Geography and Fungal Associations in Corallorhizinae (Orchidaceae)

泰勒兰是开花植物中最大的一科，种类繁多。它们都寄生在真菌上，至少在种子萌发时是这样，但人们对这种关系知之甚少。一些兰花所有的营养都依赖真菌，因为它们不能进行光合作用。珊瑚兰属的兰花是最好的例子，主要由11种主要是北美温带山地的陆地植物组成。这个小组提供了一个特殊的机会来研究植物放弃光合作用时发生的变化，因为至少有一个物种是光合作用的，而其他物种不是。这些变化包括叶绿体DNA的部分丢失，植物结构的修改，以及与其相关的真菌群体之间的转移。通过DNA序列分析重建珊瑚属及其真菌种群之间的系统发育关系将揭示兰花-真菌联系在多大程度上本质上是随机的，而不是针对某些真菌群体；添加兰花形态和位置数据将表明真菌利用的变化是否与这些因素有关。由于密集的采样，任何现代分布与谱系历史的重复相关性都将被显示出来，这可能反映了冰川后的迁徙。这将使我们更好地了解北美目前的植物分布是如何形成的。该项目结合了精心规划的实地工作，以获取兰花和真菌样本，并汇集了俄亥俄州立大学的兰花专家约翰·弗洛伊登斯坦和阿拉斯加大学的真菌专家唐纳德·泰勒的专业知识，以便于进行否则不可能的全面分析，产生可能是迄今为止对植物与微生物相互作用的最详细和最多方面的分析。该项目在许多方面对科学和其他方面都有广泛的影响。它提供了对开花植物-真菌联合、植物形态、基因谱系和地理的详细分析的现代方法的综合。因此，它可以作为今后类似系统工作的范本。它通过将这些分类群的新收藏品带入博物馆并将产生的DNA序列放入公共数据库以供所有人使用，从而加强了科学的基础设施。与中国、韩国和墨西哥科学家的互动将加强合作网络。该项目通过将研究生和本科生整合在项目中，将研究和教育结合在一起。它进一步加强了研究与教学的结合，将该项目的成果作为案例研究用于私人投资机构的系统学、微生物多样性和共生课程的教学，并将其推广到广大公众中。这包括就土地利用规划与林业局植物学家进行持续磋商，以及向不同团体介绍情况。增加对兰花-真菌关系的了解直接有利于保护，因为兰花的萌发和生长需要真菌伙伴。试图维持或重新引入濒危兰花物种的项目必须解决真菌伙伴身份和可用性的问题。

0416378Taylor Orchids comprise the largest family of flowering plants and are extremely diverse. All are parasitic on fungi at least when seeds germinate, but little is known about this relationship. Some orchids depend on fungi for all nutrition because they are non-photosynthetic. Orchids of the genus Corallorhiza are prime examples, comprising 11 species of mainly North American temperate-montane terrestrials. This group provides a special opportunity to study the changes that happen when plants give up photosynthesis, because at least one species is photosynthetic while others are not. Such changes include partial loss of chloroplast DNA, structural modifications of the plant, and shifts among the groups of their associated fungi. Reconstructing phylogenetic relationships among populations of the species of Corallorhiza and their fungi through analysis of DNA sequences will reveal to what extent the orchid-fungal association is essentially random vs. targeted to certain fungal groups; adding orchid morphology and locality data will show whether shifts in fungal utilization are at all correlated with these factors. Because of the intensive sampling, any repeated correlations of present-day distribution with lineage histories will be shown, which might reflect post-glacial migration. This will provide a better understanding of how current plant distributions in North America came to be. The project incorporates carefully planned fieldwork to obtain both orchid and fungal samples, and brings together the expertise of orchid specialist John Freudenstein at Ohio State University and fungal specialist Donald Taylor at University of Alaska to facilitate a comprehensive analysis that would not otherwise be possible, yielding perhaps the most detailed and multifaceted analysis of a plant-microbe interaction to date.This project has broad impact for science and beyond in a number of ways. It provides a synthesis of modern approaches to a detailed analysis of flowering plant-fungal associations, plant morphology, gene lineages and geography. As such, it may serve as a model for future work on similar systems. It enhances the infrastructure of science by bringing new collections of these taxa into museums where they have broad accessibility and the DNA sequences generated into public databases where they will be available to all. The interactions with scientists in China, Korea and Mexico will result in strengthened networks of cooperation. The project brings together research and education by integrating graduate and undergraduate students in the project. It further enhances the integration of research and teaching by utilization of the results of the project as a case study in the PIs' teaching in courses on systematics, microbial diversity and symbiosis, and in their outreach to the public at large. This includes ongoing consultation with forest service botanists on land use planning, as well as presentations to various groups. Increased understanding of orchid-fungus relationships has direct conservation benefits, since fungal partners are required for orchid germination and growth. Programs that attempt to maintain or reintroduce endangered species of orchids must address the issue of fungal partner identity and availability.