Introduction

Type Species	Rhizidiomyces virus	(RZV)

Virion Properties

Morphology

Virions are isometric, 60  nm in diameter (Fig. 1).

Physicochemical and Physical Properties

The buoyant density of virions in CsCl is 1.31  g/cm³; S_20wis 625S. Virions contain 10% nucleic acid.

Nucleic Acid

Virions contain a single molecule of dsDNA with a Mr of 16.8 10⁶ and a G+C ratio of 42%.

Proteins

Virions contain at least 14 polypeptides with Mr in the range of 26-84.5 10³.

Lipids

None reported.

Carbohydrates

None reported.

Genome Organization and Replication

Particles appear first in the nucleus.

Biological Properties

The virus appears to be transmitted in a latent form in the zoospores of the fungus. Activation of the virus, which occurs under stress conditions such as heat, poor nutrition, or aging, results in cell lysis.

List of Species Demarcation Criteria in the Genus

Not applicable.

List of Species in the Genus

Official virus species names are in italics. Tentative virus species names, alternative names ( ), strains or serotypes are not italicized. Virus name, host name { } and assigned abbreviation ( ) are:

Species in the Genus

Rhizidiomyces virus	{from Rhizidiomyces sp isolate F}	(RZV)

Tentative Species in the Genus

None reported.

Phylogenetic Relationships within the Genus

Not applicable.

Similarity with Other Taxa

None reported.

Derivation of Names

Rhizidio: from name of the host Rhizidiomyces sp.