Tobacco mosaic virus (TMV) is a positive-sense single-stranded RNA virus species in the genus Tobamovirus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characteristic patterns, such as "mosaic"-like mottling and discoloration on the leaves. TMV was the first virus to be discovered. Although it was known from the late 19th century that a non-bacterial infectious disease was damaging tobacco crops, it was not until 1930 that the infectious agent was determined to be a virus. It is the first pathogen identified as a virus. The virus was crystallised by W.M. Stanley. It has a similar size to the largest synthetic molecule, known as PG5.
Virusoids are circular single-stranded RNA(s) dependent on viruses for replication and encapsidation. The genome of virusoids consist of several hundred (200–400) nucleotides and does not code for any proteins.
A satellite is a subviral agent that depends on the coinfection of a host cell with a helper virus for its replication. Satellites can be divided into two major classes: satellite viruses and satellite nucleic acids. Satellite viruses, which are most commonly associated with plants, are also found in mammals, arthropods, and bacteria. They encode structural proteins to enclose their genetic material, which are therefore distinct from the structural proteins of their helper viruses. Satellite nucleic acids, in contrast, do not encode their own structural proteins, but instead are encapsulated by proteins encoded by their helper viruses. The genomes of satellites range upward from 359 nucleotides in length for satellite tobacco ringspot virus RNA (STobRV).
Plant viruses are viruses that affect plants. Like all other viruses, plant viruses are obligate intracellular parasites that do not have the molecular machinery to replicate without a host. Plant viruses can be pathogenic to vascular plants.
Brome mosaic virus (BMV) is a small, positive-stranded, icosahedral RNA plant virus belonging to the genus Bromovirus, family Bromoviridae, in the Alphavirus-like superfamily.
Tobamovirus is a genus of positive-strand RNA viruses in the family Virgaviridae. Many plants, including tobacco, potato, tomato, and squash, serve as natural hosts. Diseases associated with this genus include: necrotic lesions on leaves. The name Tobamovirus comes from the host and symptoms of the first virus discovered.
Potyvirus is a genus of positive-strand RNA viruses in the family Potyviridae. Plants serve as natural hosts. Like begomoviruses, members of this genus may cause significant losses in agricultural, pastoral, horticultural, and ornamental crops. More than 200 species of aphids spread potyviruses, and most are from the subfamily Aphidinae. The genus contains 190 species and potyviruses account for about thirty percent of all currently known plant viruses.
Papaya ringspot virus (PRSV) is a pathogenic plant virus in the genus Potyvirus and the virus family Potyviridae which primarily infects the papaya tree.
Alfalfa mosaic virus (AMV), also known as Lucerne mosaic virus or Potato calico virus, is a worldwide distributed phytopathogen that can lead to necrosis and yellow mosaics on a large variety of plant species, including commercially important crops. It is the only Alfamovirus of the family Bromoviridae. In 1931 Weimer J.L. was the first to report AMV in alfalfa. Transmission of the virus occurs mainly by some aphids, by seeds or by pollen to the seed.
The hairpin ribozyme is a small section of RNA that can act as a ribozyme. Like the hammerhead ribozyme it is found in RNA satellites of plant viruses. It was first identified in the minus strand of the tobacco ringspot virus (TRSV) satellite RNA where it catalyzes self-cleavage and joining (ligation) reactions to process the products of rolling circle virus replication into linear and circular satellite RNA molecules. The hairpin ribozyme is similar to the hammerhead ribozyme in that it does not require a metal ion for the reaction.
Cymbidium mosaic virus (CymMV) is a plant pathogenic virus of the family Alphaflexiviridae.
Prunus necrotic ringspot virus (PNRSV) is a plant pathogenic virus causing ring spot diseases affecting species of the genus Prunus, as well as other species such as rose and hops. PNRSV is found worldwide due to easy transmission through plant propagation methods and infected seed. The virus is in the family Bromoviridae and genus Ilarvirus. Synonyms of PNRSV include European plum line pattern virus, hop B virus, hop C virus, plum line pattern virus, sour cherry necrotic ringspot virus, and peach ringspot virus.
Soil-borne wheat mosaic virus is a rod-shaped plant pathogen that can cause severe stunting and mosaic in susceptible wheat, barley and rye cultivars. The disease has often been misdiagnosed as a nutritional problem, but this has actually allowed in part for the fortuitous visual selection by breeding programs of resistant genotypes. Soil-borne wheat mosaic virus is part of the genus Furovirus. Members of this genus are characterized by rigid rod-shaped particles and positive sense RNA genomes consisting of two molecules that are packaged into separate particles that code for either replication, mobility, structure or defense against the host. The virus is spread by a fungal-like protist, Polymyxa graminis, whose asexual secondary and sexual primary cycles help the virus spread. The disease produces secondary symptoms from the root cell infection. The disease is a serious contributor to loss in crop yield.
Tobacco ringspot virus (TRSV) is a plant pathogenic virus in the plant virus family Secoviridae. It is the type species of the genus Nepovirus. Nepoviruses are transmitted between plants by nematodes, thrips, mites, grasshoppers, and flea beetles. TRSV is also easily transmitted by sap inoculation and transmission in seeds has been reported. In recent cases it has also been shown to appear in bees, but no transmission to plants from bees has been noted.
Potexvirus is a genus of pathogenic viruses in the order Tymovirales, in the family Alphaflexiviridae. Plants serve as natural hosts. There are 48 species in this genus, three of which are assigned to a subgenus. Diseases associated with this genus include: mosaic and ringspot symptoms. The genus name comes from POTato virus X).
Alternanthera mosaic virus (AltMV) is a plant pathogenic virus. AltMV belongs to the virus genus Potexvirus and the virus family Alphaflexiviridae.
Bamboo mosaic virus (BaMV) is a plant pathogenic virus in the genus Potexvirus and the family Alphaflexiviridae. BaMV is a filamentous, flexuous rod, 490 nm in length and 15 nm in width. The virus has been fully sequenced and it is 6366 nucleotides long.
Orchid fleck dichorhavirus, commonly called Orchid fleck virus (OFV), is a non-enveloped, segmented, single-stranded (ss) RNA negative-strand virus, transmitted by the false spider mite, Brevipalpus californicus. OFV causes necrotic and chlorotic lesions on the leaves of many genera in the family Orchidaceae.
Fig mosaic emaravirus (FMV) is a segmented, negative sense, single-stranded RNA virus that is determined to be the causal agent of fig mosaic disease (FMD) in fig plants, Ficus carica. It is a member of the genus Emaravirus and order Bunyavirales and is transmitted mainly by the eriophyid mite Aceria ficus. FMV can cause a range of symptoms varying in severity, including leaf chlorosis, deformity, and mosaic or discoloration patterns, as well as premature fruit drop.
Tomato mottle mosaic virus is a Tobamovirus which infects Solanum lycopersicum. First detected in Mexico in 2013 from S. lycopersicum samples taken in 2009, ToMMV has since been found throughout the world. In 2014 some S. lycopersicum samples from Florida in 2010 and 2012 and a Nicotiana tabacum 'Xanthi nc' sample were retested using an assay that distinguishes ToMMV from other Tobamoviruses, especially the closely related Tomato mosaic virus and Tobacco mosaic virus. These samples tested positive for ToMMV, showing that ToMMV was widespread and had been for several years earlier than previously known.
