RUI: Mediation of Induced Resistance to Insects by a Fungal Endophyte

RUI：内生真菌诱导昆虫抗性的介导

• 批准号: 9527600
• 负责人: Thomas Bultman
• 金额: $ 16.22万
• 依托单位: Truman State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-15 至 2000-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9527600&HistoricalAwards=false
• 关键词: RUI; Mediation; Induced; Resistance; Insects

9527749 Bultman The presence of an endophytic fungus is often associated with enhanced survival and reproduction of the host grass. Because insect herbivores often cause less damage to grasses infected by the fungi compared to grasses lacking the fungal associates, the grass-fungus association has been described as a defensive mutualism. A hypothesized mechanism for this defense may be fungal-produced alkaloids that can be toxic to insects. The proposed study specifically tests if the advantage of endophyte infection to grasses is due to enhanced resistance to insects following plant damage. Laboratory experiments manipulating nutrient levels, plant damage, and fungal infection will be conducted using Chewings, hard, and tall fescues and perennial ryegrass. Plant tissue will be fed to fall and true armyworm larvae and their growth and survival monitored to assess the presence and magnitude of base level and wound-induced resistance in fungal-infected and fungal-free plants. The level of plant protein nitrogen and alkaloids will also be monitored to help interpret differences in insect performance among experimental treatments. Biomass gain and consumption of the two insect herbivores will be assessed to further evaluate mechanisms responsible for treatment effects on insect performance. The economic significance of fungal endophytes of grasses is well documented. The fungi, and the toxins they produce, have detrimental effects on livestock that translate to annual revenue losses of over $600 million in the US. The proposed research, by providing information on the basic ecology of grass endophytes, should assist efforts to manage them in agricultural settings.

9527749 Bultman 内生真菌的存在通常与宿主草的存活和繁殖增强有关。 由于与缺乏真菌伙伴的草相比，昆虫食草动物通常对被真菌感染的草造成较小的损害，因此草-真菌关联被描述为防御性互利共生。 这种防御的一种假设机制可能是真菌产生的对昆虫有毒的生物碱。 拟议的研究专门测试了草类内生菌感染的优势是否是由于植物受损后对昆虫的抵抗力增强。 将使用咀嚼型羊茅、硬而高的羊茅和多年生黑麦草进行控制营养水平、植物损害和真菌感染的实验室实验。 将植物组织喂给秋粘虫幼虫和真粘虫幼虫，并监测它们的生长和存活，以评估真菌感染和无真菌植物中基础水平和伤口诱导的抗性的存在和程度。 还将监测植物蛋白氮和生物碱的水平，以帮助解释实验处理之间昆虫性能的差异。 将评估两种食草昆虫的生物量增益和消耗，以进一步评估处理对昆虫性能影响的机制。 草类内生真菌的经济意义已有充分记载。 这些真菌及其产生的毒素对牲畜产生有害影响，导致美国每年损失超过 6 亿美元。 拟议的研究通过提供草内生菌的基本生态学信息，应有助于在农业环境中管理它们。