The Root Mycobiota of Betula aetnensis Raf., an Endemic Tree Species Colonizing the Lavas of Mt. Etna (Italy)

Betula aetnensis is an endemic tree of high conservation value, which thrives on the nutrient-poor volcanic soils Mount Etna. Since plant–microbe interactions could play a crucial role in plant growth, resource uptake, and resistance to abiotic stresses, we aimed characterize root rhizosphere microbial communities. Individuals from natural habitat (NAT) forest nursery (NURS) were surveyed through microscopy observations molecular tools: bacterial fungal automated ribosomal intergenic spacer analysis (ARISA), denaturing gradient gel electrophoresis (DGGE). B. was found be simultaneously colonized by arbuscular (AM), ectomycorrhizal (ECM), ericoid (ERM) fungi, dark septate endophytes (DSE). A diversity community observed whilst assemblage NAT plants richer than that NURS. Root communities characterized Illumina MiSeq sequencing. Most identified sequences affiliated Helotiales, Pezizales, Malasseziales. Ascomycota Basidiomycota dominated roots but differed structure composition. ECM mainly belonged Tylospora Leccinum, while Rhizopogon abundant rhizosphere. The including ERM (mostly Oidiodendron) DSE Phialocephala), appeared dominant component community. harbors extraordinarily wide array root-associated soil microorganisms, are likely involved adaptation mechanisms extreme environmental conditions volcano We argue nursery-produced seedlings lack necessary microbiota for growth development conditions.