COLLABORATIVE RESEARCH: What makes a generalist herbivore? The interplay between top-down and bottom-up forces on herbivore diet breadth

合作研究：是什么造就了多面食草动物？

• 批准号: 2030743
• 负责人: Gina Wimp
• 金额: $ 58.5万
• 依托单位: Georgetown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2030743&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; What; makes; generalist

One-third of all species on Earth are insects that eat plants (herbivores) and they are key to environmental health. For example, insect herbivores are food for other animals, such as birds, snakes, and mammals. Insect herbivores pollinate flowering plants, however they can also be pests of food crops which can reduce our food supply. Thus, to conserve natural habitats and our food supply, we must know how insect herbivores are affected by their food plants and by the animals that eat them. After decades of research, we still do not know why insect herbivores feed on particular plants. Even though very few insect herbivores are generalists which feed on many different types of plants, generalists are the most damaging pests of crops. This research will study a common generalist herbivore to answer: What allows generalist herbivores to use new plants or to feed on many different types of plants? Answering this question is key for knowing when and how pests spread onto different crops. This project will educate elementary, middle, high school, and college students. A science camp for middle school girls from low income families will be established by this project.One of the major unresolved questions in biology is to understand why there are so many different species. Insect herbivores are an ideal study group for this question because they are so diverse. Host plant use is an important driver of insect herbivores’ diversification, however, most studies examining the link between diet breadth and insect herbivore evolution focus on specialist herbivores. Focusing on specialists does not tell us which factors lead herbivores to specialize or to maintain generalism. By focusing on generalists, this project will study how selective forces from host plant use and natural enemies can lead to diet expansion or contraction, and thereby affect the evolution and diversification of insect herbivores. Using a generalist herbivore (fall webworm, Hyphantria cunea) that feeds on over 400 plant species across a wide geographic range, this project will: 1) Determine whether diet breadth is a population or individual-level trait, and test for the genetic basis of diet breadth using a candidate gene approach; 2) Investigate if local adaption to host plants is predicted by diet breadth; 3) Test how natural enemy composition and abundance affect herbivore diet breadth; 4) Test if escape from natural enemies explains diet expansion to poor quality hosts; and 5) Examine how the interplay of selective forces from host plants and natural enemies may change over time. This research will provide critically needed tests of how selective forces influence generalist herbivores and diet breadth evolution.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

地球上三分之一的物种是吃植物的昆虫（食草动物），它们是环境健康的关键。例如，昆虫食草动物是其他动物的食物，如鸟类、蛇和哺乳动物。食草昆虫为开花植物授粉，但它们也可能是粮食作物的害虫，会减少我们的食物供应。因此，为了保护自然栖息地和我们的食物供应，我们必须知道食草昆虫是如何受到它们的食物植物和以它们为食的动物的影响的。经过几十年的研究，我们仍然不知道为什么昆虫食草动物以特定的植物为食。尽管很少有食草昆虫是以多种不同类型的植物为食的多面手，但多面手是对作物最具破坏性的害虫。本研究将研究一种常见的多面手食草动物来回答：是什么让多面手食草动物使用新的植物或以许多不同类型的植物为食？回答这个问题是了解害虫何时以及如何传播到不同作物上的关键。该项目将教育小学、初中、高中和大学学生。该项目将为低收入家庭的女中学生设立科学营。生物学中未解决的主要问题之一是理解为什么有这么多不同的物种。昆虫食草动物是这个问题的理想研究群体，因为它们种类繁多。寄主植物的利用是昆虫食草动物多样化的一个重要驱动因素，然而，大多数研究饮食广度与昆虫食草动物进化之间联系的研究都集中在专门的食草动物上。关注专业并不能告诉我们哪些因素导致食草动物专业化或保持通用性。本项目将重点研究寄主植物利用和天敌的选择力如何导致食性扩张或收缩，从而影响昆虫食草动物的进化和多样化。利用一种以400多种植物为食的多面手食草动物（秋网虫，Hyphantria cunea），该项目将：1)确定饮食宽度是种群还是个体水平的特征，并使用候选基因方法测试饮食宽度的遗传基础；2)研究是否通过食性宽度预测寄主植物的局部适应性；3)测试天敌组成和丰度对草食动物食性广度的影响；4)检验对天敌的逃避是否解释了劣质宿主的饮食扩张；5)研究来自寄主植物和天敌的选择性力量的相互作用如何随时间变化。这项研究将为选择性力量如何影响多面手食草动物和饮食广度进化提供急需的测试。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Protocols for Rearing FallWebworm (Hyphantria cunea) in a Colony and Basic Methods for Laboratory and Field Experiments

在群体中饲养秋网虫（Hyphantria cunea）的方案以及实验室和现场实验的基本方法

• 发表时间: 2021
• 期刊: University of Denver Undergraduate Research Journal
• 作者: Robinson-Castillo, Maelah;Mitchell, Audrey;Fasching, Amanda;Vidal, Mayra C.;Abarca, Mariana;Wimp, Gina M.;Bieber, Blyssalyn;Vyas, Dhaval K.;Murphy, Shannon M.
• 通讯作者: Murphy, Shannon M.