Mushroom forming fungi as possible reservoir hosts for Phaeoacremoniumspecies: first occurrence of Phaeoacremonium fraxinopennsylvanicumon Flammulina velutipess. lato

Members of the genusPhaeoacremoniumare known to inhabit a wide spectrum of substrates and exhibit diverse lifestyles. Little information is available on fungicolous habits among Phaeoacremoniumspecies. During surveys to Arasbaran forests in East Azerbaijan province, Iran, in 2016, several hyphomycete isolates morphologically resembling the genusPhaeoacremoniumwere recovered from the hymenium ofFlammulina velutipess. lato in different localities with no symptoms on the cap. The isolates were identified asPh. fraxinopennsylvanicumbased on a combination of morphological traits and phylogenetic analyses ofβ -tubulingene sequence data. This is the first report on the occurrence ofPh. fraxinopennsylvanicumonF. velutipesworldwide; however, the pathogenic potential ofPh. fraxinopennsylvanicumonF. velutipesremains unclear. The data presented in the study reveal mushroom forming fungi as possible new reservoir hosts forPhaeoacremoniumspp. Hence, extensive sampling from mushroom forming fungi is required to further explore fungicolous habit ofPhaeoacremoniumspecies.