Endophytic fungal community structure in a hemiboreal forest

In this study we used high-throughput sequencing (HTS) to compare the diversity and community structure of fungi inhabiting leaves, branches and trunks of <i>Alnus incana</i> and <i>Corylus avellana</i> growing at three hemiboreal forest sites. Our analysis revealed that tree organ is the main determinant of the structure of fungal communities, while the effects of host species and locality remained secondary and negligible, respectively. The structure of fungal communities in trunks was the most distinct compared to that in leaves and branches. Foliar fungal communities were more similar within than between individual trees, implying that certain fungi may grow through parts of the tree crown. The weak effect of locality compared to host organs and species identity suggests that the variation in fungal community structure in the aboveground parts of trees depends mainly on deterministic factors rather than dispersal limitation.

本研究采用高通量测序（high-throughput sequencing，HTS）技术，对生长于3处半寒带森林样地的灰桤木（Alnus incana）和欧洲榛（Corylus avellana）的叶片、枝条及树干内定殖真菌的多样性与群落结构开展比较分析。分析结果表明，树木器官是真菌群落结构的主要决定因素，宿主物种与样地位置的影响则分别居于次要与可忽略的水平。相较于叶片和枝条中的真菌群落，树干内的真菌群落结构最为独特。叶片真菌群落在单株树木内部的相似性高于不同树木间，暗示部分真菌可通过树冠的不同部分扩散定殖。相较于宿主器官与宿主物种身份，样地位置的影响较弱，这表明树木地上部分真菌群落结构的变异主要取决于确定性因子，而非扩散限制。