title: Phytophthora viruses.
abstract: Phytophthora sp. is a genus in the oomycetes, which are similar to filamentous fungi in morphology and habitat, but phylogenetically more closely related to brown algae and diatoms and fall in the kingdom Stramenopila. In the past few years, several viruses have been characterized in Phytophthora species, including four viruses from Phytophthora infestans, the late blight pathogen, and an endornavirus from an unnamed Phytophthora species from Douglas fir. Studies on Phytophthora viruses have revealed several interesting systems. Phytophthora infestans RNA virus 1 (PiRV-1) and PiRV-2 are likely the first members of two new virus families; studies on PiRV-3 support the establishment of a new virus genus that is not affiliated with established virus families; PiRV-4 is a member of Narnaviridae, most likely in the genus Narnavirus; and Phytophthora endornavirus 1 (PEV1) was the first nonplant endornavirus at the time of reporting. Viral capsids have not been found in any of the above-mentioned viruses. PiRV-1 demonstrated a unique genome organization that requires further examination, and PiRV-2 may have played a role in late blight resurgence in 1980s-1990s.
authors.affiliation: Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, USA. cai@aesop.rutgers.edu
authors.forename: Guohong
authors.initials: G
authors.lastname: Cai
authors.forename: Bradley I
authors.initials: BI
authors.lastname: Hillman
mesh_terms: D023061:Gene Order; D005814:Genes, Viral; D016679:Genome, Viral; D010838:Phytophthora / Q000821:virology*; D012328:RNA Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*