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.
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