Tungrovirus
Tungrovirus | |
---|---|
Virus classification | |
(unranked): | Virus |
Realm: | Riboviria |
Kingdom: | Pararnavirae |
Phylum: | Artverviricota |
Class: | Revtraviricetes |
Order: | Ortervirales |
Family: | Caulimoviridae |
Genus: | Tungrovirus |
Tungrovirus is a genus of
Structure
Viruses in Tungrovirus are non-enveloped, with icosahedral and
Genus | Structure | Symmetry | Capsid | Genomic arrangement | Genomic segmentation |
---|---|---|---|---|---|
Tungrovirus | Bacilliform | T=3 | Non-enveloped | Circular | Monopartite |
Life cycle
Viral replication is nuclear/cytoplasmic. Replication follows the dsDNA(RT) replication model. The method of transcription is dsDNA(RT) transcription. Translation takes place by leaky scanning, and
Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
---|---|---|---|---|---|---|---|
Tungrovirus | Plants | None | Viral movement; mechanical inoculation | Viral movement | Nucleus | Cytoplasm | Mechanical inoculation: aphids |
Clinical
Tungro affected rice plants are stunted and have reduced numbers of tillers. The young emerging leaves develop interveinal chlorosis leading to discoloration of the leaves, starting from the tips downwards. Often the whole leaf is discolored. Plants infected at an early stage generally die prematurely. Infected plants take more time to mature because of delayed flowering. The panicles are often poorly developed and the grains are also often covered with dark brown blotches and are lighter weight than those of healthy plants.
After twelve days Tungro infection causes little damage, however there is extensive damage after one month.[3] The severe syndrome known as Tungro disease is not caused by RTBV alone - this requires coinfection with Rice tungro spherical virus (RTSV).[4]
Resistance
References
- ^ a b c d "Viral Zone". ExPASy. Retrieved 15 June 2015.
- ^ a b "Genus: Tungrovirus - Caulimoviridae - Reverse Transcribing DNA and RNA Viruses - International Committee on Taxonomy of Viruses (ICTV)". Archived from the original on 7 December 2020.
- PMID 1154651.
- ^ "Genus: Waikavirus - Secoviridae - Positive-sense RNA Viruses". International Committee on Taxonomy of Viruses. Archived from the original on 4 February 2021. Retrieved 13 December 2020.
- IRRI (ISBN 971-22-0019-1.
- ^ p. 53, "Oryza officinalis from Sukothai, Thailand, is a good source of resistance to several pests and diseases; it has been used in a number of crosses to derive high-yielding lines with multiple pest resistance."
- Bonman, J M; Khush, G S; Nelson, R J (1992). "Breeding Rice for Resistance to Pests". S2CID 86598945.
- ^ p. 520, "An accession of O. officinalis from Thailand showed high resistance to RTD (62), although it is not yet known whether this resistance is due to resistance to the vector, to the viruses themselves, or to some combination of these resistances. Results from recent research indicate that resistance to RTD is present in many wild rice species (R. Ikeda, personal communication), and perhaps some will show resistance to RTBV."