Experimental drought re‐ordered assemblages of root‐associated fungi across North American grasslands
Experimental drought re‐ordered assemblages of root‐associated fungi across North American grasslands
复制标题
DOI：
10.1111/1365-2745.13505
复制
发表时间：
2020-04
影响因子：
5.5
通讯作者：
Devon Lagueux;A. Jumpponen;Andrea Porras‐Alfaro;J. Herrera;Y. A. Chung;Lauren E. Baur;Melinda D. Smith;A. Knapp;S. Collins;Jennifer A. Rudgers
中科院分区：
文献类型：
--
作者：
Devon Lagueux;A. Jumpponen;Andrea Porras‐Alfaro;J. Herrera;Y. A. Chung;Lauren E. Baur;Melinda D. Smith;A. Knapp;S. Collins;Jennifer A. Rudgers
植物相关真菌可以改善寄主的非生物胁迫，这些真菌群落的变化可以改变植物生产力、物种相互作用、群落结构和生态系统过程。我们研究了6种北美草地生态系统类型的根相关真菌对实验性干旱（生长期降水减少66%）的响应，以确定极端干旱如何改变根相关真菌，并了解影响草地生态系统根真菌群落组成的非生物因素。真菌ITS2区域的下一代测序表明，干旱主要重新排序了真菌物种在寄主植物物种中的相对丰度，并根据寄主身份产生不同的真菌反应。与干旱敏感性较低的禾本科植物相比，在干旱条件下下降较多的禾本科植物根系真菌的群落重新排序较少。寄主身份和草地生态系统类型决定了干旱对真菌群落组成、多样性和根系定殖的影响程度，而影响真菌组成的最重要因素是植物物种身份。与真菌组成相比，真菌多样性对干旱的响应较小。在整个生态系统中，纬度和土壤pH值比实验干旱更能预测真菌多样性。干旱显著降低了侧边燕麦（graama boueloua curtipendula）的真菌多样性和均匀性，减少了蓝色格兰（grama B. gracilis）的根定植。我们的研究结果表明，预测干旱对根相关真菌的影响需要关注寄主植物身份和生态系统类型。通过将我们的发现与同一实验中土壤微生物的反应进行比较，我们提出了一个假设，即植物根系中的真菌对干旱的敏感性低于居住在土壤中的真菌。我们的研究强调了研究真菌组成在群落水平上的重新排序对于理解植物对气候变化的响应的重要性。
Plant‐associated fungi can ameliorate abiotic stress in their hosts, and changes in these fungal communities can alter plant productivity, species interactions, community structure and ecosystem processes. We investigated the response of root‐associated fungi to experimental drought (66% reduction in growing season precipitation) across six North American grassland ecosystem types to determine how extreme drought alters root‐associated fungi, and understand what abiotic factors influence root fungal community composition across grassland ecosystems. Next generation sequencing of the fungal ITS2 region demonstrated that drought primarily re‐ordered fungal species' relative abundances within host plant species, with different fungal responses depending on host identity. Grass species that declined more under drought trended toward less community re‐ordering of root fungi than species less sensitive to drought. Host identity and grassland ecosystem type defined the magnitude of drought effects on community composition, diversity and root colonization, and the most important factor affecting fungal composition was plant species identity. Fungal diversity was less responsive to drought than fungal composition. Across ecosystems, latitude and soil pH were better predictors of fungal diversity than experimental drought. Drought significantly reduced fungal diversity and evenness only in sideoats grama Bouteloua curtipendula and reduced root colonization only in blue grama B. gracilis. Our results illustrate that predicting the effects of drought on root‐associated fungi will require attention to host plant identity and ecosystem type. By comparing our findings against soil microbe responses in the same experiment, we propose the hypothesis that fungi in plant roots are less sensitive to drought than fungi inhabiting soils. Our study highlights the importance of studying community‐level re‐ordering of fungal composition for understanding plant responses to climate change.