Changes in the foliar fungal community between oak leaf flushes along a latitudinal gradient in Europe

Aim: To advance our understanding of how foliar fungal communities are structured and assembled, we assessed to what extent leaf flush and latitude can explain the within- and among-tree variation in the foliar fungal community in a foundation tree species, the pedunculate oak Quercus robur.
Location: A latitudinal gradient spanning c. 20 degrees in latitude in Europe.
Major taxa studied: The foliar fungal community on Quercus robur.
Methods: We examined the main and interactive effects of leaf flush and latitude on the foliar fungal community by sampling 20 populations of the pedunculate oak Quercus robur across the tree’s range, spanning c. 20 degrees in latitude.
Results: Species composition, but not species richness, differed between leaf flushes. Across the latitudinal gradient, species richness was highest in the central part of the oak’s distributional range, and foliar fungal community composition shifted along the latitudinal gradient. Among fungal guilds, the relative abundanc...