Nimbya alternantherae and Cercospora alternantherae: two new records of fungal pathogens on Alternanthera philoxeroides (alligatorweed) in Brazil

Abstract

Alternanthera philoxeroides is an amphibious herbaceous weed (alligatorweed) of the Amaranthaceae, and is a native of South America. It has become a very aggressive invader in many regions of the world. A preliminary survey for fungal pathogens to be used as biocontrol agents for this weed of five Brazilian States yielded two species, Nimbya alternantherae and Cercospora alternantherae. This is the first report of these species from Brazil. The pathogenicity of these fungi was tested against plants from Brazilian and Australian biotypes of A. philoxevoides. N. alternantherae was shown to be very damaging and appears to have biocontrol potential.