Rhizopycnis vagum gen. et sp. nov., a new coelomycetous fungus from roots of melons and sugarcane

A new coelomycete, Rhizopycnis vagum, is described that has been isolated from the roots of melons in Texas, Guatemala and Honduras as well as from the roots of sugarcane in Taiwan. This fungus is a contributing factor in vine decline of melons grown in the Rio Grande Valley of Texas. This asexually reproducing fungus is characterized by large, black pycnidial conidiomata, enteroblastic conidiogenesis, and conidia that are hyaline to brown with 1-3 septa. The similarities of this fungus to Stagonospora and other coelomycetes are discussed. The ITS region of the rDNA of the holotype culture and additional isolates of R. vagum were sequenced and used to confirm that a fungus with similar characteristics from sugarcane roots in Tai wan was conspecific.