Dissertation Research: Maintenance of Polymorphism in a Natural Plant-Pathogen Interaction

论文研究：天然植物-病原体相互作用中多态性的维持

• 批准号: 9701320
• 负责人: Phyllis Coley
• 金额: $ 0.43万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-06-01 至 1999-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9701320&HistoricalAwards=false
• 关键词: Dissertation; Research; Maintenance; Polymorphism; Natural

9701320 Coley The relationships between plants and their pathogens are not well understood, yet these systems present fascinating questions which bear upon fundamental issues of evolutionary ecology. This research will address one such topic, the maintenance of resistance and virulence polymorphisms. This study will undertake an integrated investigation of various hypotheses for the maintenance of polymorphism in the native wild sunflower (Helianthus annuus) and its fungal rust (Puccinia helianthi). First, a series of garden experiments will determine whether there are detectable fitness costs associated with bearing unnecessary resistance or virulence alleles. Such costs might balance the benefits of resistance or virulence, resulting in polymorphic populations. In addition, both direct and indirect fitness benefits of resistance will be examined in natural populations. A frequency-dependent advantage for rare resistance or virulence genotypes might also be important to the maintenance of polymorphism, and a controlled garden experiment will be performed to test this hypothesis. Finally, surveys of natural populations in Utah will compare polymorphism in areas favorable or unfavorable for the rust, and will examine polymorphism in populations of differing sizes and degrees of isolation. The proposed research will critically test a variety of hypotheses for the maintenance of virulence and resistance polymorphisms, and will make a valuable contribution to our understanding of the evolutionary dynamics of natural plant-pathogen systems.

9701320 Coley 植物与其病原体之间的关系尚不清楚，但这些系统提出了与进化生态学的基本问题有关的令人着迷的问题。这项研究将解决这样一个主题：耐药性和毒力多态性的维持。 本研究将对维持本土野生向日葵（Helianthus annuus）及其真菌锈病（Puccinia helianthi）多态性的各种假设进行综合研究。首先，一系列花园实验将确定是否存在与承受不必要的抗性或毒力等位基因相关的可检测的适应性成本。这些成本可能会平衡耐药性或毒力的好处，从而产生多态性群体。此外，还将在自然群体中检验抵抗力的直接和间接健身益处。罕见抗性或毒力基因型的频率依赖性优势对于多态性的维持也可能很重要，并且将进行受控花园实验来检验这一假设。最后，对犹他州自然种群的调查将比较有利于或不利于锈病的地区的多态性，并将检查不同规模和隔离程度的种群的多态性。 拟议的研究将批判性地测试各种维持毒力和抗性多态性的假设，并将为我们理解天然植物病原体系统的进化动力学做出宝贵的贡献。