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Geminiviridae
''Geminiviridae'' is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: bright yellow mosaic, yellow mosaic, yellow mottle, leaf curling, stunting, streaks, reduced yields. They have single-stranded circular DNA genomes encoding genes that diverge in both directions from a virion strand origin of replication (i.e. geminivirus genomes are ambisense). According to the Baltimore classification they are considered class II viruses. It is the largest known family of single stranded DNA viruses. Mastrevirus and curtovirus Transmission (medicine), transmission is via various leafhopper species (e.g. maize streak virus and other African streak viruses are transmitted by ''Cicadulina mbila''), the only known topocuvirus species, ''Tomato pseudo-curly top virus'', is transmitted by the treehopper ''Micrutalis malleifera'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastrevirus
''Mastrevirus'' is a genus of ssDNA viruses, in the family ''Geminiviridae''. Mostly monocotyledonous plants serve as natural hosts. They are vectored by planthoppers. There are 45 species in this genus. Diseases associated with this genus include: maize streak virus: maize streak disease (MSD). Capsid proteins ''Mastreviruses'' have an unusually diverse range of capsid proteins among the Geminiviridae. While all other genus, genera have species with essentially identical proteins (and their producing genetic sequences) among themselves, ''Mastrevirus'' has seven protein clusters and three species that each constitute their own. Taxonomy The following species are recognized: *''Axonopus compressus streak virus'' (ACSV) *''Bromus catharticus striate mosaic virus'' *''Camellia chlorotic dwarf-associated virus'' (CaCDaV) *''Citrus chlorotic dwarf-associated virus'' (CCDaV) *''Chickpea chlorosis Australia virus'' *''Chickpea chlorosis virus'' *''Chickpea chlorotic dwarf virus'' *'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maize Streak Virus
''Maize streak virus'' (MSV) is a virus primarily known for causing maize streak disease (MSD) in its major host, and which also infects over 80 wild and domesticated grasses. It is an insect-transmitted maize pathogen in the genus ''Mastrevirus'' of the family ''Geminiviridae'' that is endemic in sub-Saharan Africa and neighbouring Indian Ocean island territories such as Madagascar, Mauritius and La Reunion. The A-strain of MSV (MSV-A) causes sporadic maize streak disease epidemics throughout the maize growing regions of Africa. MSV was first described by the South African entomologist Claude Fuller who referred to it in a 1901 report as "mealie variegation". The development of conventionally resistant maize varieties has been a priority since the 1950s in Kenya, Nigeria, South Africa and elsewhere, with a good deal of success: however, there are several genes associated with resistance, and breeding is complex. Transgenically resistant or genetically modified maize varietie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maize Streak Virus
''Maize streak virus'' (MSV) is a virus primarily known for causing maize streak disease (MSD) in its major host, and which also infects over 80 wild and domesticated grasses. It is an insect-transmitted maize pathogen in the genus ''Mastrevirus'' of the family ''Geminiviridae'' that is endemic in sub-Saharan Africa and neighbouring Indian Ocean island territories such as Madagascar, Mauritius and La Reunion. The A-strain of MSV (MSV-A) causes sporadic maize streak disease epidemics throughout the maize growing regions of Africa. MSV was first described by the South African entomologist Claude Fuller who referred to it in a 1901 report as "mealie variegation". The development of conventionally resistant maize varieties has been a priority since the 1950s in Kenya, Nigeria, South Africa and elsewhere, with a good deal of success: however, there are several genes associated with resistance, and breeding is complex. Transgenically resistant or genetically modified maize varietie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Becurtovirus
''Becurtovirus'' is a genus of viruses, in the family ''Geminiviridae ''Geminiviridae'' is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: b ...''. Dicotyledonous plants serve as natural hosts. There are three species in this genus. Taxonomy The following three species are assigned to the genus: *'' Beet curly top Iran virus'' *'' Exomis microphylla latent virus'' *'' Spinach curly top Arizona virus'' Structure Viruses in ''Becurtovirus'' are non-enveloped, with icosahedral geometries, and T=1 symmetry. Genomes are circular and non-segmented, around 3.0kb in length. Life cycle Viral replication is nuclear. Entry into the host cell is achieved by penetration into the host cell. Replication follows the ssDNA rolling circle model. DNA-templated transcription is the method of transcription. The virus exi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomato Pseudo-curly Top Virus
''Topocuvirus'' is a genus of viruses, in the family ''Geminiviridae''. Dicotyledonous plants serve as natural hosts. There is only one species in this genus: ''Tomato pseudo-curly top virus''. Diseases associated with this genus include: vein swelling, curling of the leaves and leaf distortion. Structure Viruses in ''Topocuvirus'' are non-enveloped, with icosahedral geometries, and T=1 symmetry. The diameter is around 22 nm, with a length of 38 nm. Genomes are circular and non-segmented, around 2.86kb in length. Life cycle Viral replication is nuclear. Entry into the host cell is achieved by penetration into the host cell. Replication follows the ssDNA rolling circle model. DNA-templated transcription is the method of transcription. The virus exits the host cell by nuclear pore export, and tubule-guided viral movement. Dicotyledonous plants serve as the natural host. The virus is transmitted via a vector (treehopper Treehoppers (more precisely typical treehoppe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eragrovirus
''Eragrovirus'' is a genus of viruses, in the family ''Geminiviridae ''Geminiviridae'' is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: bri ...''. Dicotyledonous plants serve as natural hosts. There is only one species in this genus: ''Eragrostis curvula streak virus''. Structure Viruses in ''Eragrovirus'' are non-enveloped, with icosahedral geometries, and T=1 symmetry. Genomes are circular and non-segmented, around 3.0kb in length. Life cycle Viral replication is nuclear. Entry into the host cell is achieved by penetration into the host cell. Replication follows the ssDNA rolling circle model. DNA-templated transcription is the method of transcription. The virus exits the host cell by nuclear pore export, and tubule-guided viral movement. Dicotyledonous plants serve as the natural host. Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curtovirus
''Curtovirus'' is a genus of ssDNA viruses, in the family ''Geminiviridae''. Dicotyledonous plants serve as natural hosts. Curtoviruses are transmitted by leafhoppers. There are three species in this genus. Diseases associated with this genus include: Curly top disease. Structure Viruses in ''Curtovirus'' are non-enveloped, with icosahedral geometries, and T=1 symmetry. The diameter is around 22 nm, with a length of 38 nm. Genomes are circular and non-segmented, around 3.0kb in length. Life cycle Viral replication is nuclear. Entry into the host cell is achieved by penetration into the host cell. Replication follows the ssDNA rolling circle model. Dna templated transcription is the method of transcription. The virus exits the host cell by nuclear pore export, and tubule-guided viral movement. Dicotyledonous plants serve as the natural host. The virus is transmitted via a vector (beet leafhopper The beet leafhopper (''Circulifer tenellus''), also sometimes known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grablovirus
''Grablovirus'' is a genus of plant viruses in the family ''Geminiviridae ''Geminiviridae'' is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: bri ...''. The genus has three species. Taxonomy The following species are recognized: *'' Grapevine red blotch virus'' *'' Prunus latent virus'' *'' Wild Vitis latent virus'' References {{Taxonbar, from=Q29002221 Geminiviridae Virus genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baltimore Classification
Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a distinct group. Seven Baltimore groups are described that take into consideration whether the viral genome is made of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), whether the genome is single- or double-stranded, and whether the sense of a single-stranded RNA genome is positive or negative. Baltimore classification also closely corresponds to the manner of replicating the genome, so Baltimore classification is useful for grouping viruses together for both transcription and replication. Certain subjects pertaining to viruses are associated with multiple, specific Baltimore groups, such as specific forms of translation of mRNA and the host range of different types of viruses. Structural characteristics such as the shape of the vir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whitefly
Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The Aleyrodidae are a family in the suborder Sternorrhyncha and at present comprise the entire superfamily Aleyrodoidea, related to the superfamily Psylloidea. The family often occurs in older literature as "Aleurodidae", but that is a junior synonym and accordingly incorrect in terms of the international standards for zoological nomenclature. Aleyrodidae are small insects, most species with a wingspan of less than 3 mm and a body length of 1 mm to 2 mm. Many are so small that their size complicates their control in greenhouses because they can only be excluded by screening with very fine mesh; in fact they can enter mesh so fine that many of their natural enemies cannot come in after them, so that unchecked whitefly populations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bemisia Tabaci
The silverleaf whitefly (''Bemisia tabaci'', also informally referred to as the sweet potato whitefly) is one of several species of whitefly that are currently important agricultural pests. A review in 2011 concluded that the silverleaf whitefly is actually a species complex containing at least 40 morphologically indistinguishable species. The silverleaf whitefly thrives worldwide in tropical, subtropical, and less predominately in temperate habitats. Cold temperatures kill both the adults and the nymphs of the species. The silverleaf whitefly can be confused with other insects such as the common fruitfly, but with close inspection, the whitefly is slightly smaller and has a distinct wing color that helps to differentiate it from other insects. While the silverleaf whitefly had been known in the United States since 1896, in the mid-1980s an aggressive strain appeared in poinsettia crops in Florida. For convenience that strain was referred to as (biotype B), to distinguish it f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Viruses
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 higher plants. Most plant viruses are rod-shaped, with protein discs forming a tube surrounding the viral genome; isometric particles are another common structure. They rarely have an envelope. The great majority have an RNA genome, which is usually small and single stranded (ss), but some viruses have double-stranded (ds) RNA, ssDNA or dsDNA genomes. Although plant viruses are not as well understood as their animal counterparts, one plant virus has become very recognizable: ''tobacco mosaic virus'' (TMV), the first virus to be discovered. This and other viruses cause an estimated US$60 billion loss in crop yields worldwide each year. Plant viruses are grouped into 73 genera and 49 families. However, these figures relate only to cultivated plants, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
