Cassava brown streak virus (Cassava Brown Streak Virus, CBSV) | BCH-ORGA-SCBD-115107 | Organism | Biosafety Clearing-House


Organism (ORGA)

published: 16 Aug 2019 last updated: 29 Jun 2020
Organism information
Cassava brown streak virus
Kingdom Orthornavirae
Phylum Pisuviricota
Class Stelpaviricetes
Order Patatavirales
Family Potyviridae
Genus Ipomovirus
Species Cassava brown streak viruses
  • Cassava brown streak carlavirus
  • Cassava brown streak potyvirus
  • Cassava Brown Streak Virus
  • CBSV
Additional classification
IV ((+)ssRNA)
Characteristics related to biosafety
The first report of Cassava brown streak disease was in Northeastern Tanzania (Tanganyika) in 1936.
The virus can be found in cassava growing regions in Central and East Africa.
The virus infects mature (or nearly mature) leaves and characteristically causes chlorotic or necrotic vein banding. Dark, necrotic lesions appear within the tuber tissue and lead to post-harvest spoilage. Lesions can also sometimes appear on young (green) stems, but this is uncommon. Disease symptoms vary greatly and are influenced strongly by environmental conditions.

The virus is transmitted mechanically via cuttings. Researchers have noted  a correlation between whitefly (Bemisia tabaci) population abundance and outbreaks of cassava brown streak disease. However, attempts to demonstrate whitefly as a vector for the virus have been unsuccessful thusfar.
  • Research
  • Other (Phytopathogen)
Additional Information
Cassava brown streak virus is 650 nm long and has a genome that consists of single strand of RNA and approximately 8.9 kilobases in length. The genome is encapsulated by the 45 kiloDalton coat protein.

Cassava brown streak disease can also be caused by closely related virus, Ugandan cassava brown streak virus. Symptoms are indistinguishable between the two viral agents.