Dissertation Research: Effects of Self Incompatibility on Inbreeding Depression with Respect to Plant Defenses

自交不亲和性(SI)是开花植物中的一种基于遗传的系统，它防止自交受精和近亲繁殖的不利影响。然而，SI在杂草和入侵物种中并不常见，在这些物种中，少数个体经常在新的栖息地定居。普通马尾松是这种模式的一个例外，因为它是一种非常成功的入侵植物，确实表现出SI。但是，马尾草的SI强度在种群内表现出显著的差异，这使得它成为研究自交对植物活力的影响，特别是自交对植物防御机制的影响的有用系统。本研究的目的是了解马尾草中SI强度的变化如何影响(1)诱导的植物反应，(2)寄主-植物质量，(3)植物-食草动物-天敌的相互作用。这项研究将利用来自不同SI强度的基因的植物的自交和异交后代来解决这些目标，并结合温室、田间和实验室研究。这项研究将促进我们对植物-食草动物-天敌相互作用和调控植物对草食性反应的机制的理解，并对杂草的治理和进一步了解其对周围生态系统的影响具有重要意义。

Self-incompatibility (SI) is a genetically based system in flowering plants that prevents self-fertilization and the adverse effects of inbreeding. However, SI is uncommon among weedy and invasive species in which small numbers of individuals often colonize new habitats. Common horsenettle, Solanum carolinense L., represents an exception to this pattern as it is a highly successful invasive that does exhibit SI. But the strength of SI in horsenettle exhibits significant variation within populations, making it a useful system for exploring the impacts of selfing on plant vigor, particularly the effects of selfing on plant defense mechanisms. The objectives of this research are to understand how variation in the strength of SI in horsenettle influences (1) induced plant responses, (2) host-plant quality, and (3) plant-herbivore-natural enemy interactions. The study will address these objectives using selfed and outcrossed progeny of plants derived from genets that differ in the strength of SI and employing a combination of greenhouse, field and laboratory studies. This research will advance our understanding of plant-herbivore-natural enemy interactions and the mechanisms regulating plant responses to herbivory and also has important implications for managing weeds and further understanding their impacts on surrounding ecosystems.