DISSERTATION RESEARCH: Fusarium and Wild Chilies: Fungal Fruit Pathogens, Coevolution and Local Adaptation

大多数物种依靠其他物种生存和繁殖。 因此，共同进化（物种之间的相互进化变化）可以说在生物多样性的起源和组织中起着主导作用。这项研究使用了一种新的模型系统来研究共同进化动力学：野生辣椒及其果实相关的真菌病原体。辣椒的辣味（由抗菌化学物质辣椒素引起）可以保护辣椒果实免受真菌的破坏。从玻利维亚的野生辣椒中获得的真菌菌株用于实验室和田间实验，以检查辣椒辣度的变化如何选择真菌对植物防御的耐受性并驱动真菌的局部适应。将在玻利维亚进行田间试验，以获得关于真菌昆虫媒介生态及其对田间水果感染的影响的信息。这项研究考察了共同进化的动力学，这可能是世界上最受欢迎的香料植物之一的主要特性：辣椒的辛辣。辣椒抑制食源性病原体的能力被认为是其在世界范围内驯化和使用的原因。了解有利于辣椒素类化合物在野生植物中进化的选择压力可能会为我们使用这些化学品提供深入了解，并可用于医药，食品储存，作物开发以及植物病虫害管理。此外，本科生研究助理在当地和玻利维亚接受与该项目有关的指导。

Most species depend on other species for survival and reproduction. Thus, coevolution (reciprocal evolutionary change between species) arguably plays a dominant role in the origin and organization of biodiversity. The proposed research uses a novel model system to study coevolutionary dynamics: wild chili peppers and their fruit-associated fungal pathogens. The spiciness of chilies (caused by the antimicrobial chemical capsaicin) protects chili fruits from fungi that can destroy seeds. Fungal strains obtained from wild chilies in Bolivia are used in lab and field experiments to examine how the variation in chili spiciness selects for fungal tolerance to plant defenses and drives fungal local adaptation. Field experiments will be conducted in Bolivia to gain information about the ecology of fungal insect vectors and their impact on infection of fruits in the field. The research examines the coevolutionary dynamics that are likely responsible for the major property of one of the most popular spice plants in the world: the spiciness of chilies. The ability of chilies to inhibit food borne pathogens is believed to be responsible for their domestication and use worldwide. Understanding the selective pressures that favored the evolution of capsaicinoids in wild plants may provide insight into our use of these chemicals and has applications for medicine, food storage, crop development, and the management of plant diseases and pests. In addition, undergraduate research assistants are mentored in association with this project both locally and in Bolivia.