Article

Genetically distinct strains of Cassava brown streak virus in the Lake Victoria basin and the Indian Ocean coastal area of East Africa.

Department of Applied Biology, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland.
Archives of Virology (Impact Factor: 2.28). 02/2009; 154(2):353-9. DOI: 10.1007/s00705-008-0301-9
Source: PubMed

ABSTRACT Six isolates of Cassava brown streak virus (CBSV, genus Ipomovirus; Potyviridae) from the Lake Victoria basin in Uganda and Tanzania were characterized. Virus particles were 650 nm long. The complete coat protein (CP)-encoding sequences (1,101 nucleotides, nt) were 90.7-99.5 and 93.7-99.5% identical at the nt and amino acid (aa) levels, respectively. The 3' untranslated region was 225, 226 or 227 nt long. These eight isolates were only 75.8-77.5% (nt) and 87.0-89.9% (aa) identical when compared to the partial CP sequences (714 nt) of six CBSV isolates characterized previously from the costal lowlands of Tanzania and Mozambique. Hence, two genetically different and geographically separated populations of CSBV exist in East Africa.

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