| Tymoviridae | |
|---|---|
Virus classification  | |
| (unranked): | Virus |
| Realm: | Riboviria |
| Kingdom: | Orthornavirae |
| Phylum: | Kitrinoviricota |
| Class: | Alsuviricetes |
| Order: | Tymovirales |
| Family: | Tymoviridae |
| Genera | |
Tymoviridae is a family of single-stranded positive sense RNA viruses in the order Tymovirales . Plants serve as natural hosts. There are 42 species in this family, assigned to three genera, with two species unassigned to a genus. [1] [2]
The family includes the following three genera: [2]
Additionally, the following two species are not assigned to a genus: [2]
The virions are non-enveloped and isometric with a diameter of around 30 nm, with an icosahedral structure and a triangulation number T=3. [1]
The linear genome is between of 6–7.5 kilobases in length [1] and encodes one large open reading frame. It is capped at the 5’ terminus. The 3’ terminus may have a tRNA-like structure or a polyA tract, depending upon the species. The genome is relatively cytosine rich.[ citation needed ]
| Genus | Structure | Symmetry | Capsid | Genomic arrangement | Genomic segmentation |
|---|---|---|---|---|---|
| Maculavirus | Icosahedral | T=3 | Non-enveloped | Linear | Monopartite |
| Marafivirus | Icosahedral | T=3 | Non-enveloped | Linear | Monopartite |
| Tymovirus | Icosahedral | T=3 | Non-enveloped | Linear | Monopartite |
Viral replication is cytoplasmic, and is lysogenic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. Translation takes place by leaky scanning. The virus exits the host cell by monopartite non-tubule guided viral movement. Plants serve as the natural host. The virus is transmitted via a vector (insects). Transmission routes are vector and mechanical. [1]
| Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
|---|---|---|---|---|---|---|---|
| Maculavirus | Plants | None | Viral movement; mechanical inoculation | Viral movement | Cytoplasm | Cytoplasm | Mechanical inoculation: pseudococcid mealybugs; Mechanical inoculation: aphids |
| Marafivirus | Plants | None | Viral movement; mechanical inoculation | Viral movement | Cytoplasm | Cytoplasm | Mechanical inoculation: pseudococcid mealybugs; Mechanical inoculation: aphids |
| Tymovirus | Plants | None | Viral movement; mechanical inoculation | Viral movement | Cytoplasm | Cytoplasm | Mechanical: beetles; sap |
Bromoviridae is a family of viruses. Plants serve as natural hosts. There are six genera in the family.
Closteroviridae is a family of viruses. Plants serve as natural hosts. There are four genera and 59 species in this family, seven of which are unassigned to a genus. Diseases associated with this family include: yellowing and necrosis, particularly affecting the phloem.
Potyviridae is a family of positive-strand RNA viruses that encompasses more than 30% of known plant viruses, many of which are of great agricultural significance. The family has 12 genera and 235 species, three of which are unassigned to a genus.
Sequivirus is a genus of viruses in the order Picornavirales, in the family Secoviridae. Plants serve as natural hosts. There are three species in this genus. Diseases associated with this genus include: PYFV: vein-yellowing, yellow flecks and yellow/green mosaic symptoms in parsnip, and ‘yellow net', followed by yellow spots and leaf distortion in celery.
Closterovirus, also known as beet yellows viral group, is a genus of viruses, in the family Closteroviridae. Plants serve as natural hosts. There are 17 species in this genus. Diseases associated with this genus include: yellowing and necrosis, particularly affecting the phloem. This genus has a probably worldwide distribution and includes among other viral species the Beet yellows virus and Citrus tristeza virus, rather economically important plant diseases. At least some species require vectors such as aphids or mealybugs for their transmission from plant to plant.
Benyvirus is a genus of viruses, in the family Benyviridae. Plant serve as natural hosts. There are four species in this genus. Diseases associated with this genus include: BNYVV: rhizomania.
Pomovirus is a genus of viruses, in the family Virgaviridae. Plants and dicotyledons serve as natural hosts. There are five species in this genus. Diseases associated with this genus include: dwarfing of shoots (mop-top) and potato spraing disease. The name of the genus is derived from Potato mop-top virus, Potato mop-top virus, giving rise to Pomovirus.
Tobravirus is a genus of viruses, in the family Virgaviridae. Plants serve as natural hosts. There are three species in this genus. Diseases associated with this genus include: SBWMV: green and yellow mosaic.
Cucumovirus is a genus of viruses, in the family Bromoviridae. Plants serve as natural hosts. There are four species in this genus.
Endornaviridae is a family of viruses. Plants, fungi, and oomycetes serve as natural hosts. There are 31 species in this family, assigned to 2 genera. Members of Alphaendornavirus infect plants, fungi and the oomycete Phytophthora sp., members of Betaendornavirus infect ascomycete fungi.
Alphaflexiviridae is a family of viruses in the order Tymovirales. Plants and fungi serve as natural hosts. There are 65 species in this family, assigned to six genera. Diseases associated with this family include: mosaic and ringspot symptoms.
Betaflexiviridae is a family of viruses in the order Tymovirales. Plants and fungi serve as natural hosts. There are 108 species in this family, assigned to 13 genera in two subfamilies. Diseases associated with this family include mosaic and ringspot symptoms.
Virgaviridae is a family of positive-strand RNA viruses. Plants serve as natural hosts. The name of the family is derived from the Latin word virga (rod), as all viruses in this family are rod-shaped. There are currently 59 species in this family, divided among seven genera.
Macluravirus is a genus of viruses, in the family Potyviridae. Plants serve as natural hosts. There are ten species in this genus.
Allexivirus is a genus of viruses in the order Tymovirales, in the family Alphaflexiviridae. Shallot, onion, and garlic serve as natural hosts. There are 13 species in this genus, seven of which are assigned to a subgenus. Diseases associated with this genus include: mosaic and ringspot symptoms.
Bromovirus is a genus of viruses, in the family Bromoviridae. Plants serve as natural hosts. There are six species in this genus.
Capillovirus is a genus of viruses in the order Tymovirales, in the family Betaflexiviridae. Plants, pome fruits, citrus, and pear serve as natural hosts. There are four species in this genus. Diseases associated with this genus include: abnormal graft union, possibly black necrotic leaf spot disease.
Maculavirus is a genus of viruses in the order Tymovirales, in the family Tymoviridae. Plants serve as natural hosts. There is only one species in this genus: Grapevine fleck virus.
Marafivirus is a genus of viruses in the order Tymovirales, in the family Tymoviridae. Plants serve as natural hosts. There are 11 species in this genus.
Tymovirus is a genus of viruses in the order Tymovirales, in the family Tymoviridae. Plants serve as natural hosts. There are 28 species in this genus.