Dissertation Research: Biotic Interactions and Mycorrhizal Dynamics in Drought-Stressed Pinyon Pine

论文研究：干旱胁迫松树的生物相互作用和菌根动力学

• 批准号: 0206654
• 负责人: Catherine Gehring
• 金额: $ 1万
• 依托单位: Northern Arizona University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206654&HistoricalAwards=false
• 关键词: Dissertation; Research; Biotic; Interactions; Mycorrhizal

Project Summary:Current global climate change models predict increases in the frequency and intensity ofdrought in the southwestern U.S. In pinyon-juniper woodlands, we hypothesize that drought stressleads to increased competition between pinyon and juniper, greater dependence of pinyon onfacilitative nurse plants, and changes in pinyon ectomycorrhizal (EM) fungal abundance andcommunity structure. Because EM fungi can alleviate environmental stress by increasing water andnutrient uptake by the host plant, it is important to understand factors that affect these mutualists.The goal of this project is to examine how competition and facilitation affect pinyon survival andgrowth, as well as their EM fungi. We will use a combination of field experiments, greenhousestudies, and molecular tools (RFLP analysis and DNA sequencing) to identify EM fungal species.The results of our study will 1) quantify EM fungal diversity and distribution in pinyon-juniperwoodlands, 2) provide data on plant responses and EM fungal community shifts in response tocompetition and facilitation, and 3) contribute to the current library of EM fungal sequences.Because many of these fungi can only be identified with molecular tools, the latter objective isnecessary to allow comparisons of ecological data on fungi from different locations to begin tounderstand the factors that affect their abundance and distribution.

项目摘要：当前的全球气候变化模型预测美国西南部干旱的频率和强度将会增加。在松树-杜松林地中，我们假设干旱胁迫导致松树和杜松之间的竞争加剧，松树对促进性保育植物的依赖性增加，以及松树外生菌根（EM）真菌丰度和群落结构的变化。由于EM真菌可以通过增加寄主植物对水分和养分的吸收来缓解环境压力，因此了解影响这些互惠共生者的因素是很重要的。本项目的目标是研究竞争和促进作用如何影响松属植物的生存和生长，以及它们的EM真菌。我们将结合使用田间实验、温室研究和分子工具本研究的结果将1）量化针叶林-杜松林地EM真菌的多样性和分布，2）提供植物对竞争和促进的反应和EM真菌群落变化的数据，和3）有助于目前的EM真菌序列库。因为这些真菌中的许多只能用分子工具鉴定，后一个目标是必要的，以便比较来自不同地点的真菌生态数据，开始了解影响其丰度的因素，分布