- Hofmann B., Dreyling L., Dal Grande F., Otte J. & Schmitt I.
- Frontiers in Microbiology
- 14: 1067906 [14 p.]
- doi: 10.3389/fmicb.2023.1067906
Introduction: Trees interact with fungi in mutualistic, saprotrophic, and
pathogenic relationships. With their extensive aboveground and belowground
structures, trees provide diverse habitats for fungi. Thus, tree species identity is an
important driver of fungal community composition in forests.
Methods: Here we investigate how forest habitat (bark surface vs. soil) and tree
species identity (deciduous vs. coniferous) affect fungal communities in two
Central European forests. We assess differences and interactions between fungal
communities associated with bark surfaces and soil, in forest plots dominated
either by Fagus sylvatica, Picea abies, or Pinus sylvestris in two study regions in
southwestern and northeastern Germany.
Results: ITS metabarcoding yielded 3,357 fungal amplicon sequence variants
(ASVs) in the northern and 6,088 in the southern region. Overall, soil communities
were 4.7 times more diverse than bark communities. Habitat type explained 48–
69% of the variation in alpha diversity, while tree species identity explained >1–
3%. NMDS ordinations showed that habitat type and host tree species structured
the fungal communities. Overall, few fungal taxa were shared between habitats,
or between tree species, but the shared taxa were highly abundant. Network
analyses, based on co-occurrence patterns, indicate that aboveground and
belowground communities form distinct subnetworks.
Discussion: Our study suggests that habitat (bark versus soil) and tree species
identity are important factors structuring fungal communities in temperate
European forests. The aboveground (bark-associated) fungal community is
currently poorly known, including a high proportion of reads assigned to “unknown
Ascomycota” or “unknown Dothideomycetes.” The role of bark as a habitat and
reservoir of unique fungal diversity in forests has been underestimated.
Keywords: biodiversity, fungal diversity, metabarcoding, tree microbiome, rhytidome.
- Wednesday, 08 March 2023 13:47