Collaboration: The Role of Plant-Pathogen Interactions in Explaining and Constraining Weed Invasions: Testing Theories of Biotic Resistance and the Natural Enemies Hypothesis

入侵生物生态学的一个中心问题涉及到为什么一些引进的植物物种不能在栖息地成功生存，而另一些却成为种群众多的有害入侵者。两种相互竞争的理论被提出来回答这个问题，重点是天敌在调节入侵植物物种的种群动态方面的作用。天敌假说是经典生物控制计划的基础，它提出成功的入侵者会把控制它们的害虫和病原体留在它们的栖息地。生物抗性假说认为，大多数入侵生物都是天然食草动物和病原体的成功目标，而成功的入侵只是通常情况下的例外。本项目将使用三叶草和burclover作为模型系统来检验这两个假设。它将通过田间和温室实验的结合来检验植物与病原体的相互作用，以比较本地三叶草和外来三叶草，试图通过不同地点的情况进行分类。它将检验一种预测，即疾病抗性应该在本地宿主中更为普遍——这与生物抗性假说相一致。

Gilbert & Parker University of California-Berkeley & -Santa Cruz DEB - 9806517 & 9808501 A central question in the ecology of invading organisms involves why some introduced plant species fail to succeed in a habitat while others become noxious invaders with high populations. Two competing theories have been posed to answer this question focusing on the role of natural enemies in regulating the population dynamics of invading plant species. The natural enemies hypothesis, the foundation for classical biological control programs, proposes that successful invaders leave behind the pests and pathogens that control them in their home habitats. The biotic resistance hypothesis suggests that most invading organisms are the successful targets of natural herbivores and pathogens and that successful invasions are the exception to the usual run of things. This project will test these two hypotheses using clover and burclover as a model system. It will examine plant-pathogen interactions using a combination of field and greenhouse experiments to compare native vs. exotic clovers in trying to sort through situations in different locations. It will test the prediction that disease resistance should be more prevalent in native hosts - consistent with the biotic resistance hypothesis.