Tobacco streak virus (TSV) is a plant pathogenic

virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1 ...

of the family ''

Bromoviridae ''Bromoviridae'' is a family of viruses. Plants serve as natural hosts. There are six genera in the family. Taxonomy The following genera are assigned to the family: * ''Alfamovirus'' * ''Anulavirus'' * ''Bromovirus'' * ''Cucumovirus'' * ''Ilar ...

'', in the genus ''

Ilarvirus ''Ilarvirus'' is a genus of positive-strand RNA viruses in the family ''Bromoviridae''. Plants serve as natural hosts. There are 22 species in this genus. Structure Viruses in the genus ''Ilarvirus'' are non-enveloped, with icosahedral and quas ...

''. It has a wide host range, with at least 200 susceptible species. TSV is generally more problematic in the tropics or warmer climates. TSV does not generally lead to epidemics, with the exception of sunflowers in India and Australia, and peanuts in India.

Host and symptoms

TSV has been reported worldwide in North and South America, Europe, India, Japan, Australia, New Zealand and South America. TSV has a wide host range including both monocots and dicots. Economically important crop hosts include peanuts, sunflower, soybean, cranberry, cotton, chickpea and mung beans. As with many plant viruses, diagnosis is very difficult because TSV has very wide host range and has different effects depending on the host being infected. Symptoms of TSV may include black streaks on stems and leaves, stunted growth, chlorosis, leaf mosaic, lodging, and deformed growing tips, to name a few. On tobacco plants, TSV causes chlorosis, with a unique pattern of white or dark necrotic leaf tissue close to the veins of the leaf. As its name implies, necrotic streaks are found on leaf veins of infected plants. Symptoms are strongly influenced by temperature. For example, plants experiencing a temperature of 20° Celsius will develop small necrotic spots while at temperatures above 30° Celsius, necrotic spots will become large necrotic arcs. Symptoms are not sufficient to correctly identify TSV - serology and PCR techniques are required.

Disease cycle

TSV purified from infected plants consists of a ss-RNA genome encapsulated by spheroid particles made up of coat protein subunits. The coat protein subunits play a key role in the life cycle of the virus. Once the virus has penetrated into the host cells, it uncoats and releases its viral genomic RNA into the cytoplasm and expressed proteins replicate. After replication, the dsRNA genome is synthesized from genomic ssRNA. Subgenomic RNA4 is translated producing capsid proteins and the new virus particles are assembled. The coat protein of TSV plays an important role in its life cycle. It protects the viral genome and plays a role in cell to cell movement. Once the virus becomes systemic, it can be transmitted by vectors. TSV requires a living plant to survive for a period of time. The virus may be transmitted by thrips vector, mechanical damage, pollen or dodder.

Environment

Severe outbreaks of TSV typically occur under climatic conditions that allow large thrips populations to develop and when large quantities of pollen are being produced by the host plant. These conditions generally occur in warmer months but are dependent on rainfall and weeds in the field. Modes of Transmission: * ''Insect vectors:'' Several species of thrips serve as vectors of TSV, including ''Microcephalothrips abdominali''s and ''

Thrips tabaci ''Thrips tabaci'' is a species of very small insect in the genus ''Thrips'' in the order Thysanoptera. It is commonly known as the onion thrips, the potato thrips, the tobacco thrips or the cotton seedling thrips. It is an agricultural pest that ...

''. * ''Seed transmission'': Seed transmission of TSV is possible depending on the crop. * ''Pollen transmission:'' TSV may be transmitted via pollen, this is also crop dependent. * ''Dodder transmission:'' May be infected via '' Cuscuta campestris,'' a parasitic plant often found in agricultural fields''.'.''

Management

Control for TSV is difficult, and there are no chemical controls available for the virus. The best management practices are to maintain good sanitation, purchase certified seed, control insects that serve as vectors, and provide barrier crops. ''Sanitation: ''Remove plant debris after harvest or any plant material that may serve as a source of inoculum. Due to its wide host range, TSV may also infect many weed species, so keeping fields free of weeds is a good control strategy. ''Chemical Control'': Preventative control of disease dispersal may be possible if insecticide is sprayed for the trips vector. ''Barrier Crops:'' One common form of management for viruses is to plant a desirable host for thrips around the cropping system. The thrips will insert their stylet and “clean” off any virus on their stylet before moving to the target crop. ''Barrier Crops:'' One common form of management for viruses is to plant a desirable host for thrips around the cropping system. The thrips will insert their stylet and “clean” off any virus on their stylet before moving to the target crop.

References

External links

ICTVdB - The Universal Virus Database: Tobacco streak virus

Affected organisms

Asparagus Asparagus, or garden asparagus, folk name sparrow grass, scientific name ''Asparagus officinalis'', is a perennial flowering plant species in the genus ''Asparagus''. Its young shoots are used as a spring vegetable. It was once classified in ...

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Asparagus officinalis Asparagus, or garden asparagus, folk name sparrow grass, scientific name ''Asparagus officinalis'', is a perennial flowering plant species in the genus ''Asparagus''. Its young shoots are used as a spring vegetable. It was once classified in ...

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Faba bean ''Vicia faba'', commonly known as the broad bean, fava bean, or faba bean, is a species of vetch, a flowering plant in the pea and bean family Fabaceae. It is widely cultivated as a crop for human consumption, and also as a cover crop. Varieti ...

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Vicia faba ''Vicia faba'', commonly known as the broad bean, fava bean, or faba bean, is a species of vetch, a flowering plant in the pea and bean family Fabaceae. It is widely cultivated as a crop for human consumption, and also as a cover crop. Variet ...

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Cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus ''Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor perce ...

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Gossypium herbaceum ''Gossypium herbaceum'', commonly known as Levant cotton, is a species of cotton native to the semi-arid regions of sub-Saharan Africa and Arabia, where it still grows in the wild as a perennial shrub. Description ''G. herbaceum'' has high stems ...

'' * Sun flower *

Groundnut Groundnut may refer to: * Seeds that ripen underground, of the following plants, all in the Faboideae subfamily of the legumes: ** '' Best Basketball Player'', Obinna Udunni ** '' Arachis villosulicarpa'', a perennial peanut species ** ''Vigna sub ...

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Dahlia Dahlia (, ) is a genus of bushy, tuberous, herbaceous perennial plants native to Mexico and Central America. A member of the Asteraceae (former name: Compositae) family of dicotyledonous plants, its garden relatives thus include the sunflower, ...

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Cranberry Cranberries are a group of evergreen dwarf shrubs or trailing vines in the subgenus ''Oxycoccus'' of the genus ''Vaccinium''. In Britain, cranberry may refer to the native species ''Vaccinium oxycoccos'', while in North America, cranberry ...

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Vaccinium macrocarpon ''Vaccinium macrocarpon'' (also called large cranberry, American cranberry and bearberry) is a North American species of cranberry of the subgenus '' Oxycoccus'' and genus ''Vaccinium''. The name cranberry, comes from shape of the flower stam ...

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Tomato The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word ...

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Lycopersicon esculentum The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word , ...

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Tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

Nicotiana tabacum ''Nicotiana tabacum'', or cultivated tobacco, is an annually grown herbaceous plant of the ''Nicotiana'' genus. The plant is tropical in origin, is commonly grown throughout the world, and is often found in cultivation. It grows to heights bet ...

Climbing rose Garden roses are predominantly Hybrid (biology), hybrid roses that are grown as ornamental plants in private or public gardens. They are one of the most popular and widely cultivated groups of flowering plants, especially in temperate climates. A ...

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Rosa setigera ''Rosa setigera'', commonly known as the climbing rose, prairie rose, and climbing wild rose, is a species of shrub or vine in the Rosaceae (rose) family native to central and eastern North America. Description ''R. setigera'' has trailing or ...

'' * Common bean, ''

Phaseolus vulgaris ''Phaseolus vulgaris'', the common bean, is a herbaceous annual plant grown worldwide for its edible dry seeds or green, unripe pods. Its leaf is also occasionally used as a vegetable and the straw as fodder. Its botanical classification, alo ...

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Soybean The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean, which has numerous uses. Traditional unfermented food uses of soybeans include soy milk, from which tofu an ...

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Glycine max Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinogeni ...

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Red clover ''Trifolium pratense'', the red clover, is a herbaceous species of flowering plant in the bean family Fabaceae, native to Europe, Western Asia, and northwest Africa, but planted and naturalized in many other regions. Description Red clov ...

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Trifolium pratense ''Trifolium pratense'', the red clover, is a herbaceous species of flowering plant in the bean family Fabaceae, native to Europe, Western Asia, and northwest Africa, but planted and naturalized in many other regions. Description Red clove ...

External links

Tobacco streak ''ilarvirus''
{{DEFAULTSORT:Tobacco Streak Virus Bromoviridae Viral plant pathogens and diseases Soybean diseases