''Machlomovirus'' is a genus of
plant virus
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.
M ...
es, in the family ''
Tombusviridae
''Tombusviridae'' is a family of single-stranded positive sense RNA plant viruses. There are three subfamilies, 17 genera, and 95 species in this family. The name is derived from ''Tomato bushy stunt virus'' (TBSV).
Genome
All viruses in the f ...
''. Plants serve as natural hosts. There is only one species in this genus: ''Maize chlorotic mottle virus''
(MCMV), which causes significant losses in
maize
Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. Th ...
production worldwide. MCMV was first identified in the U.S. state of
Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
causing
Maize lethal necrosis disease
Maize lethal necrosis disease (MLN disease, MLND, corn lethal necrosis) is a viral disease affecting maize (corn) predominantly in East Africa, Southeast Asia and South America, which was recognised in 2010. It is caused by simultaneous infection w ...
/MLN/corn lethal necrosis, a severe disease that negatively affects all stages of development for maize plants.
Structure
Viruses in ''Machlomovirus'' are non-enveloped, with icosahedral and spherical geometries, and T=3 symmetry. The diameter is around 28-34 nm. Genomes are linear, around 4–5.4kb in length.
Life cycle
Viral replication is cytoplasmic. 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, using the premature termination model of subgenomic RNA transcription is the method of transcription. Translation takes place by leaky scanning, and suppression of termination. The virus exits the host cell by tubule-guided viral movement. Plants serve as the natural host. Transmission routes are mechanical, seed borne, and contact.
Even a small incidence of seed transmission is problematic: Although Kimani et al. 2021 finds MCMV to be almost incapable of successfully making the jump from contaminated seed to infecting a
seedling
A seedling is a young sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embry ...
, even a small infected proportion of a field will infect the entire field (via vector) unless quickly removed.
References
External links
Viralzone: MachlomovirusICTV*
{{Taxonbar, from=Q6723796
Tombusviridae
Viral plant pathogens and diseases
Virus genera