Ministry of Education Key Laboratory of Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, 200438, China.
Fundación para el Estudio de Especies Invasivas (FuEDEI), Hurlingham, Buenos Aires, 999071, Argentina.
New Phytol. 2023 Aug;239(4):1464-1474. doi: 10.1111/nph.19065. Epub 2023 Jun 9.
The ecological and evolutionary processes shaping community structure and functions of microbial symbionts are known to be scale-dependent. Nonetheless, understanding how the relative importance of these processes changes across spatial scales, and deciphering the hierarchical metacommunity structure of fungal endophytes has proven challenging. We investigated metacommunities of endophytic fungi within leaves of an invasive plant (Alternanthera philoxeroides) across wide latitudinal transects both in its native (Argentina) and introduced (China) ranges to test whether metacommunities of fungal endophytes were structured by different drivers at different spatial scales. We found Clementsian structures with seven discrete compartments (distinctive groups of fungal species with coincident distribution ranges), which coincided with the distribution of major watersheds. Metacommunity compartments were explicitly demarcated at three spatial scales, that is, the between-continent, between-compartment, and within-compartment scales. At larger spatial scales, local environmental conditions (climate, soil, and host plant traits) were replaced by other geographical factors as principal determinants of metacommunity structure of fungal endophytes and community diversity-function relationships. Our results reveal novel insights into the scale dependency of diversity and functions of fungal endophytes, which are likely similar for plant symbionts. These findings can potentially improve our understanding of the global patterns of fungal diversity.
塑造微生物共生体群落结构和功能的生态和进化过程是具有尺度依赖性的。尽管如此，理解这些过程在不同空间尺度上的相对重要性，以及解析真菌内生菌的层次化元群落结构，一直具有挑战性。我们调查了入侵植物（空心莲子草）叶片内生真菌的元群落，该植物分布范围广泛，横跨其原生（阿根廷）和引入（中国）地区的宽纬度地带，以检验内生真菌的元群落是否由不同的驱动因素在不同的空间尺度上构成。我们发现了具有七个离散隔室的克莱门茨结构（具有一致分布范围的真菌物种的不同群体），这与主要流域的分布相对应。元群落隔室在三个空间尺度上明确划定，即洲际间、隔室间和隔室内尺度。在更大的空间尺度上，局部环境条件（气候、土壤和宿主植物特征）被其他地理因素所取代，成为真菌内生菌元群落结构和群落多样性-功能关系的主要决定因素。我们的研究结果揭示了内生真菌多样性和功能的尺度依赖性的新见解，这可能与植物共生体相似。这些发现可能有助于我们更好地理解真菌多样性的全球模式。
