How do mycorrhizal fungal traits influence ecosystem functioning?

菌根真菌特征如何影响生态系统功能？

• 批准号: RGPIN-2018-04169
• 负责人: Chagnon, PierreLuc
• 金额: $ 2.4万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=712760
• 关键词: How; do; mycorrhizal; fungal; traits

Mycorrhizal fungi (MF) associate with a majority of plants worldwide. They receive a significant portion of plant photosynthesis products, and in exchange they provide their host plants with an improved nutrition and tolerance to biotic and abiotic stresses. Given the large fraction of plant-derived carbon (C) that MF receive, they are highly likely to influence major steps of the C cycle. Many studies have indeed showed that MF can drastically influence C cycling through the alteration of litter decomposition or of plant primary productivity. However, different species of MF vary considerably in their traits, which may translate into different impacts on C cycling and ecosystem functioning more broadly. A trait-based framework is necessary to better predict how specific traits of MF influence ecosystem processes. This is the core of my research program. I focus on a specific group of MF, namely arbuscular mycorrhizal (AM) fungi, which are the most widespread group of MF. Using a variety of techniques, my research will contribute to answer the following questions: 1- Do AM fungi stabilize soil organic matter? We will assess, for example, the impact of AM fungi on the integration of plant-derived C within soil aggregates, and we will determine whether AM fungi negatively impact the decomposing activity of other soil fungi. 2- Do plants recruit AM fungi with specific traits? This work will significantly advance our understanding of AM fungal ecology, but also of plant ecology: it has been recognized by several authors that plant functional strategies not only integrate their own traits or characteristics, but also the traits of their microbial symbionts, such as AM fungi. We may thus expect trait correlations between plants and AM fungi. This would facilitate the integration of AM fungi in C cycling models, because plant traits are much easier to measure than fungal traits: it would be convenient to estimate the latter with the former. 3- What is the residence time of plant-derived C in AM fungal tissues? Given the large amount of C transferred to AM fungi, we must better understand its fate in the soil. If fast-growing AM fungi quickly replace their tissues and rapidly respire back plant-derived C to the atmosphere, then an increased allocation of C to AM fungi under global chance might not translate into an increased soil C storage, for example. We urgently need to characterize C turnover in AM fungal tissue, in this regard. Overall, my research program will offer a cohesive attempt to advance our understanding how AM fungi drive soil C cycling. Using a trait-based approach, the work presented here will also pave the way for studying functional strategies in AM fungi This, in itself, will be a major advancement of the field: plant ecology is an excellent example of how a trait-based approach can bring novel questions and insights in a scientific discipline. My aim is to promote a similar leap forward in AM fungai ecology.

菌根真菌（MF）与全球大部分植物相关。他们获得了很大一部分植物光合作用产品，作为交换，他们为宿主植物提供了对生物和非生物胁迫的耐受性的改善。鉴于MF接收的植物衍生碳（C）的大部分，它们极有可能影响C周期的主要步骤。许多研究确实表明，MF可以通过改变垃圾分解或植物一级生产力的改变会极大地影响C循环。但是，不同种类的MF在其性状上有很大差异，这可能会转化为对C循环和生态系统发挥作用的不同影响。必须进行基于特征的框架，以更好地预测MF的特定特征如何影响生态系统过程。这是我的研究计划的核心。我专注于一组特定的MF，即Arbuscular mycorrhizal（am）真菌，这是MF中最广泛的群体。使用各种技术，我的研究将有助于回答以下问题： 1-真菌稳定土壤有机物吗？例如，我们将评估AM真菌对植物衍生的C在土壤聚集体中的整合的影响，我们将确定AM真菌是否对其他土壤真菌的分解活性产生负面影响。 2-植物是否具有特定特征的真菌招募真菌？这项工作将大大提高我们对AM真菌生态学的理解，也将对植物生态学的理解：它被几位作者认可，这些作者不仅构成了其自身的特征或特征，而且还整合了其微生物共生体的特征，例如AM真菌。因此，我们可能期望植物与AM真菌之间的性状相关性。这将有助于在C自行车模型中进行AM真菌的整合，因为植物特征比真菌性状要容易得多：与前者估算后者是方便的。 3-在AM真菌组织中植物衍生的C的停留时间是多少？鉴于大量的C转移到了AM真菌，我们必须更好地了解其在土壤中的命运。如果快速增长的AM真菌迅速替换其组织，并迅速将植物衍生的C迅速替换为大气，那么在全球机会下，C向AM真菌的分配增加可能不会转化为增加的土壤C储存量。在这方面，我们迫切需要表征AM真菌组织中的C周转。 总体而言，我的研究计划将提供一个凝聚力的尝试，以提高我们的理解，并了解AM真菌如何驱动土壤C骑自行车。使用基于特质的方法，此处介绍的工作还将为研究AM Fungi中的功能策略铺平道路，这本身将是该领域的主要进步：植物生态学是基于特征的方法如何在科学学科中带来新颖的问题和见解的一个很好的例子。我的目的是在AM真菌生态学中促进类似的飞跃。