DISSERTATION RESEARCH: Does hosting arbuscular mycorrhizal fungi in modular structures facilitate discrimination against cheaters?

论文研究：在模块化结构中容纳丛枝菌根真菌是否会促进对作弊者的歧视？

• 批准号: 1405347
• 负责人: James Bever
• 金额: $ 1.94万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1405347&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Does; hosting; arbuscular

The majority of terrestrial plant species depend on symbiotic fungi that live inside their roots ("mycorrhizal fungi") to both meet their mineral nutrient demands and increase their defenses against pests and disease. However, many strains of fast-growing mycorrhizal fungi have evolved to exploit their hosts without providing any of these services, leaving plants with stunted growth and increased susceptibility to environmental stress. Brian Steidinger and James Bever of Indiana University (IU) seek to identify how plants can defend themselves against "cheater" fungi. The researchers enhance the impact of their scientific work through their involvement in public and minority outreach programs. Steidinger will integrate under-represented minorities in the sciences into his work at IU through the James Holland Summer Research Initiative (SRI). The SRI program brings both high school and freshmen college students to IU to participate in independent research. Steidinger will train SRI students how to measure mycorrhizal fungi and identify fungal cheaters, providing them with hands-on experience working in a lab setting. Further, Steidinger will recruit IU undergraduates to assist with the experimental and data analysis portions of the proposed research, helping them build skills they can apply towards independent thesis work. This research will enhance ongoing research by this team by providing a means to directly test model predictions using molecular techniques, measure the impact of AMF on plant nutrition, and expand an ongoing experiment to compare podocarps to plants that do not form nodulated roots. In addition, the researchers will test model predictions in a comparative study of AMF composition in a New Zealand podocarp forest. To achieve this, they created a theoretical model that identified features of a host plant that should increase their ability to spatially segregate and terminate resource investment into cheater strains. Second, they developed an experimental system of beneficial and cheater fungi to determine the effectiveness of defenses in different plant hosts. Finally, they collected roots from a forest system in order to determine if the defenses in their experimental system are effective against cheater fungi in the field. Steidinger and Bever hope to discover not only how plants defend themselves against exploitative fungi, but to shed light on common features of plant defenses that are likely to be applicable to a variety of mutualisms.

大多数陆生植物物种依赖于生活在其根部的共生真菌（“菌根真菌”）来满足其矿物质营养需求并增加其对害虫和疾病的防御。然而，许多快速生长的菌根真菌菌株已经进化到利用它们的宿主而不提供任何这些服务，使植物生长受阻，对环境胁迫的敏感性增加。印第安纳州大学的布莱恩·施泰丁格和詹姆斯·贝弗试图确定植物如何抵御“骗子”真菌。研究人员通过参与公共和少数民族外展计划来提高他们的科学工作的影响力。Steidinger将通过James Holland Summer Research Initiative（SRI）将科学领域代表性不足的少数民族融入他在IU的工作中。SRI计划将高中和大一学生带到IU参加独立研究。Steidinger将培训SRI学生如何测量菌根真菌和识别真菌骗子，为他们提供在实验室环境中工作的实践经验。此外，Steidinger将招募IU本科生协助拟议研究的实验和数据分析部分，帮助他们建立可以应用于独立论文工作的技能。这项研究将通过提供一种使用分子技术直接测试模型预测的方法来加强该团队正在进行的研究，测量AMF对植物营养的影响，并扩大正在进行的实验，以比较Podocarps与不形成分枝根的植物。此外，研究人员还将在新西兰Podocarp森林AMF组成的比较研究中测试模型预测。为了实现这一目标，他们创建了一个理论模型，该模型确定了宿主植物的特征，这些特征应该增加它们在空间上分离和终止资源投资到作弊菌株的能力。其次，他们开发了一个有益真菌和欺骗真菌的实验系统，以确定不同植物宿主的防御有效性。最后，他们从森林系统中收集了根系，以确定他们实验系统中的防御措施是否能有效对抗田间的作弊真菌。施泰丁格和贝弗不仅希望发现植物如何保护自己免受剥削性真菌的侵害，而且希望揭示植物防御的共同特征，这些特征可能适用于各种互惠关系。