DISSERTATION RESEARCH: Testing for genetic discontinuities across multiple spatial scales in a widespread cranberry pathogen

该项目的目标是确定炭疽菌属中一种重要的真菌病原体的遗传结构，这种真菌在北美各地侵染野生和栽培的蔓越莓及相关植物物种。这种真菌由两个进化分支组成；一个分支广泛存在，一个多世纪以来一直被认为是蔓越莓的病原菌，而另一个分支则是一种新出现的病害。本研究将探讨野生和栽培蔓越莓沼泽的生态景观特征如何与基因流相互作用，从而在多个空间尺度上塑造这种病原菌的进化和繁殖模式。这种真菌能够有性繁殖和克隆繁殖，并已知在不同的种群中采用不同的繁殖策略。克隆种群具有在有利条件下快速传播的能力，而有性种群往往具有更多的遗传多样性，因此在面对环境扰动时具有更大的适应潜力。因此，了解这种病原体的繁殖策略及其对景观特征的依赖可以为紧急疾病的传播提供一般的洞察。这项研究对开发有效的管理工具，帮助减轻该病原菌在蔓越莓农场造成的重大经济损失具有重要意义。作为该项目的一部分开发的分子标记系统将为该真菌的进化、系统学和疾病生态学的其他研究提供便利。该项目还将支持高中生在分子和真菌生物学方面的培训。该项目加强了两个研究机构之间的合作关系，这两个研究机构是马鲁奇蓝莓和蔓越莓研究中心和纽约植物园。

The goal of this project is to determine the genetic structure of an important fungal pathogen in the genus Colletotrichum, which infects wild and cultivated cranberries and related plant species throughout North America. This fungus is comprised of two evolutionary clades; one group is widespread and has been recognized as a pathogen of cranberry for more than a century while the other is an emerging disease. This research will examine how features of the ecological landscape interact with gene flow among wild and cultivated cranberry bogs, to shape the evolution and mode of reproduction of this pathogen at multiple spatial scales. The fungus is capable of reproducing both sexually and clonally and known to employ different reproductive strategies in different populations. Clonal populations have the ability to spread rapidly under favorable conditions while sexual populations tend to be more genetically diverse, and thus have a greater adaptive potential in the face of environmental perturbations. Therefore, understanding the reproductive strategy of this pathogen and its dependence on landscape features provides general insight into how emergent diseases may spread. This research has important implications for the development of effective management tools that will assist in mitigating significant economic losses caused by this pathogen on cranberry farms. A molecular marker system developed as part of this project will facilitate other research on the evolution, systematics and disease ecology of this fungus. This project will also support the training of high school students in molecular and fungal biology. The project strengthens a collaborative relationship between two research institutions, the P.E. Marucci Center for Blueberry and Cranberry Research and the New York Botanical Garden.