Large-sporedDrechslera giganteais aBipolarisspecies causing disease on the invasive grassMicrostegium vimineum

摘要

Environmentally damaging invasive plants can also serve as reservoir hosts for agricultural pathogens.Microstegium vimineumis an invasive C4 annual grass that is present throughout the midwestern and eastern United States. It can reach high densities in disturbed areas such as crop-forest interfaces, which creates the potential for pathogen spillover fromM. vimineumto agricultural crops and native plants. A previous study that surveyed disease onM. vimineumfound a large-sporedBipolarisspecies that was widespread onM. vimineumand also isolated from co-occurring native grasses. Here, we report that the large-spored fungus isolated fromM. vimineumand the native grassElymus virginicusisDrechslera gigantea, based on comparison with published descriptions of morphological traits, and establish thatD. giganteais a pathogen ofM. vimineumandE. virginicus. We review the phylogenetic placement and taxonomic history ofD. giganteaand propose that it be reassigned to the genusBipolarisasBipolaris gigantea.