Collaborative Research: Does Escape From Natural Enemies Contribute to Invasiveness of Introduced Plants? A Test of the Evolution of Increased Competitive Ability Hypothesis

合作研究：逃离天敌是否会导致引入植物的入侵？

• 批准号: 0315127
• 负责人: Robert Johnson
• 金额: --
• 依托单位: Medaille College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0315127&HistoricalAwards=false
• 关键词: Collaborative; Research; Does; Escape; Natural

Invasive, exotic plants are currently a major threat to natural areas because they can spread through communities and replace native vegetation. Invasive species are believed to be second only to habitat loss in terms of their impact on native diversity, but the mechanisms that allow plants to become invasive are still poorly understood. We propose to investigate the mechanisms promoting invasiveness in Solidago gigantea, a species native to North America and an invasive exotic in Europe. We plan to test the Evolution of Increased Competitive Ability (EICA) hypothesis, which holds that because specialized natural enemies may be absent from the introduced range, exotic plants may evolve to invest less in anti-herbivore defenses and thereby gain a competitive advantage over native plants. In a series of experiments, we will compare European and US goldenrods in terms of their defensive chemistry, their performance in the presence and absence of herbivores, and their ability to support growth of both a specialist and a generalist insect. The EICA hypothesis predicts that European goldenrods should invest less in secondary compounds, and therefore should support better insect performance and have a growth advantage in the absence of herbivores. If tolerance to herbivory, or the ability to recover following herbivore damage, has associated fitness costs as suggested by some recent studies, then European goldenrods would also be expected to have reduced abilities to compensate for damage, compared to US goldenrods.

入侵的外来植物目前是对自然区域的主要威胁，因为它们可以在社区中传播并取代本地植被。 就对本地多样性的影响而言，入侵物种被认为仅次于栖息地丧失，但人们对植物变得具有入侵性的机制仍知之甚少。 我们建议研究促进巨花一枝黄花入侵的机制，巨花一枝黄花是一种原产于北美的物种，在欧洲是一种外来入侵物种。 我们计划检验竞争能力增强的进化（EICA）假说，该假说认为，由于引入范围内可能不存在专门的天敌，外来植物可能会进化为在反草食动物防御方面投入较少，从而获得相对于本土植物的竞争优势。 在一系列实验中，我们将比较欧洲和美国黄花菜的防御化学性质、它们在食草动物存在和不存在的情况下的表现，以及它们支持专业昆虫和通才昆虫生长的能力。 EICA 假说预测，欧洲黄花应该减少对次生化合物的投资，因此应该支持更好的昆虫性能，并在没有食草动物的情况下具有生长优势。 如果像最近的一些研究表明的那样，对草食的耐受性或食草动物损伤后的恢复能力与健康成本相关，那么与美国黄花相比，欧洲黄花的补偿损伤的能力也将降低。