Arbuscular mycorrhizal fungi (AMF,Phylum Glomeromycota) are soil and root-dwelling,obligate plant root symbiotic organisms present in most terrestrial environments.Their occurrence anddiversity have important roles in plant nutrition,abiotic and biotic stress (incl.pathogen) resistance andsoil quality,and in diversity and functioning of host plant communities and nutrient cycling ofecosystems.Therefore,understanding the taxonomic and functional diversity of AMF is the topic ofincreasing importance.