Patterns and processes in endophyte ecology - studies in optimal and extreme habitats of European Beech to reveal the underlying principles

欧洲山毛榉是中欧最重要的树种之一。由于其与众多微观和宏观生物的紧密联系，超生物(Holobion)深刻地影响着森林生态系统中的营养相互作用。然而，对这些相互联系的模式和过程仍然知之甚少。在本项目中，主要研究人员将评估山毛榉树叶栖息的内生真菌多样性的多样性格局及其对凋落物分解过程的贡献。在他们的研究中，欧洲山毛榉在德国阿尔卑斯山的两个不同的栖息地将被比较。为了减少随机参数的影响，即那些不是研究重点的参数，将在山毛榉树线上部和一个温带山谷地点安装两个具有相似遗传特征的幼树的植物仪系统。此外，实验室实验将揭示海拔相关参数(温度、树叶和凋落物的化学成分、真菌群落的多样性和组成)对先前内生真菌分解凋落物过程的影响。该项目侧重于山毛榉树叶凋落物真菌分解的基本过程以及凋落物和活树叶真菌群落发展过程中的驱动力。气候数据以及有关植物适合性、叶片和凋落物生物化学的综合数据将不断得到评估，并为中央元基因组和(元)转录组分析提供背景。对广泛数据的综合分析将使起因(海拔)与观察到的模式(真菌群落的基因表达、多样性、组成和季节性发展)和过程(凋落物分解)之间存在因果联系。最终的微阵列基因表达实验将通过在转录水平上分析具有内生生命阶段的分解真菌的代谢适应，来弥合分类和功能多样性之间的差距。

The European Beech (Fagus sylvatica) is one of the most important trees in Central Europe. Due to its tight interconnection with a myriad of micro- and macroscopic organisms the superorganism (holobiont) profoundly influences trophic interactions in forest ecosystems. However, still little is known about patterns and processes of these interconnections.In the present project, the principal investigators will assess diversity patterns of beech-leaf-inhabiting endophytic fungal diversity and their contribution to processes of litter decomposition. During their studies two contrasting habitats for European beech in the German Alps will be compared. In order to reduce the impact of random parameters, i.e. those not in focus of the study, two phytometer systems with young genetically similar beech trees will be installed at the upper beech tree line and at a temperate valley site. In addition, laboratory experiments will unravel the impact of altitude-dependent parameters (temperature, chemical composition of leaves and litter, diversity and composition of fungal communities) on litter decomposition processes by previously endophytic fungi. The project focuses on fundamental processes during fungal decomposition of beech leaf litter and driving forces during the development of fungal communities in litter and living leaves. Climate data as well as comprehensive data on plant fitness, leaf and litter biochemistry will be continuously assessed and provide the background for the central metagenome and (meta)transcriptome analyses. The integrative analyses of a broad spectrum of data will allow for causal connection of causes (altitude) with observed patterns (gene expression, diversity, composition and seasonal development of the fungal community) and processes (litter decomposition). Final microarray gene expression experiments will bridge the gap between taxonomic and functional diversity by analysing metabolic adaptations of decomposer fungi with an endophytic life stage on the transcriptomic level.