Collaborative Research: Metabolic Bet-Hedging as a mechanism for the maintenance of functional diversity in tree-ectomycorrhizal mutualisms

合作研究：代谢下注对冲作为维持树外生菌根互利共生功能多样性的机制

• 批准号: 2316522
• 负责人: Holly Moeller
• 金额: $ 83.87万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-10-01 至 2027-09-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2316522&HistoricalAwards=false
• 关键词: Collaborative; Research; Metabolic; Bet; Hedging

This project will test how interactions between trees and soil fungi help trees to adapt to changing environments. In temperate forests, trees rely on partnerships, or symbioses, with belowground fungi that help them to obtain the nutrients they need for growth. These symbioses can be incredibly diverse. For example, Douglas-fir is a commercially valuable tree that can have dozens of different fungal species on its root system at the same time. This project tests the idea that Douglas-fir trees maintain this fungal diversity as a way of adapting to variation in the environment. In other words, much like human investors might maintain a portfolio of stocks, fir trees might maintain a portfolio of fungi to “bet-hedge” against unpredictable changes in their environment. Having many fungal partners at the same time might guarantee that at least some of them are able to provide nutrients to the trees even when the environment is unfavorable. To test this hypothesis, the project uses experiments in greenhouses, mathematical models, and field surveys of fungal diversity. In addition to improving knowledge of how beneficial interactions between species affect natural biodiversity, this project will also provide valuable data on Douglas-fir, a commercially and ecologically important tree in the western United States. The results will help scientists to predict how Douglas-fir and its fungal partners will respond to warmer, drier future climate conditions. The project also provides training to the next generation of American scientists, including fieldwork experiences for local high school students.The Douglas-fir ectomycorrhizal symbiosis meets the bet-hedging hypothesis’s assumptions of (1) long-lived partners that must tolerate variable environments, (2) trait variation across mutualist partners, and (3) evidence of variation in partner quality. This project advances eco-evolutionary theory for mutualisms by combining greenhouse experiments that measure tree investments in fungal partners of different quality, mathematical models that predict portfolio diversity based on environmental variation, and fieldwork to quantify fungal diversity across a gradient of environmental conditions. Collectively, these approaches will allow researchers to (1) quantify optimal tree investment strategies in temporally fluctuating environments, (2) test for evidence of bet-hedging across the distribution of coastal Douglas-fir, and (3) link fungal diversity to host tree performance. The project supports three pre-tenure faculty members, provides training opportunities for postdocs, technicians, and student researchers, and supports course-based research experiences and scientific training for college transfer students and teenage volunteers.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.

该项目将测试树木和土壤真菌之间的相互作用如何帮助树木适应不断变化的环境。在温度森林中，树木依靠伙伴关系或符号与地下真菌，可帮助他们获得生长所需的营养。这些符号可能非常多样化。例如，道格拉斯 - 福尔（Douglas-Fir）是一棵具有商业上有价值的树木，其根系上可以在其根系上具有数十种不同的真菌物种。该项目测试了道格拉斯 - 火树维持这种真菌多样性的想法，以适应环境变化。换句话说，就像人类投资者可能维持股票的投资组合一样，FIR树可能会维持真菌的投资组合，以“押注围墙”，以抵抗其环境中的不可预测的变化。同时拥有许多真菌伴侣可以保证，即使环境不利，至少有些人也能够为树木提供营养。检验这一假设，该项目使用了真菌多样性的温室，数学模型和现场调查中的实验。除了提高对物种之间的有益相互作用如何影响自然生物多样性的知识外，该项目还将提供有关Douglas-Fir的宝贵数据，Douglas-Fir是美国西部的商业和生态重要树。结果将帮助科学家预测道格拉斯 - 费尔及其真菌伙伴将如何应对更温暖的驾驶员未来气候条件。该项目还为下一代美国科学家提供培训，包括针对当地高中生的实地考察经验。 Douglas-Fir poctomycorrhizal符号符合围墙假设的假设对（1）必须耐受可变环境的长期伴侣的假设，（2）共同性伴侣之间的性状变化，以及（3）伴侣质量变化的证据。该项目通过结合温室实验来促进互助的生态进化理论，这些实验衡量了不同质量，数学模型的真菌伙伴的树木投资，这些模型可以根据环境变化来预测投资组合的多样性，以及量化环境条件梯度的真菌多样性的现场工作。总的来说，这些方法将使研究人员能够（1）量化暂时波动环境中的最佳树木投资策略，（2）测试在沿海道格拉斯 - 局部分布的贝特希德的证据，以及（3）真菌多样性与宿主树的绩效联系起来。该项目支持三名居民的教职员工，为博士后，技术人员和学生研究人员提供培训机会，并支持基于课程的研究经验和针对大学转学学生和青少年志愿者的科学培训。该奖项反映了NSF的法定任务，并通过该基金会的知识分子优点和广泛的影响来评估NSF的法定任务。