 Dead arm of grapevine is caused by an ascomycete fungal plant pathogen.This pathogen produces sexual spores (ascospores) in the teleomorph stage and asexual spores (conidia) during the anamorph stage.When the pathogen is in the teleomorph stage it is referred to as "Cryptosporella viticola" and during the anamorph stage is it called "Phomopsis viticola".