First Record of Spiraling Whitefly in Coastal Kenya: Emergence, Host Range, Distribution and Association with Cassava Brown Streak Virus Disease

Abstract

Unconfirmed reports of a spiraling whitefly-like pest suspected to be contributing to high cassava brown streak disease (CBSD) incidences on cassava prompted a study to determine its presence and importance in coastal Kenya. Multistage sampling was conducted to determine occurrence and distribution of the whitefly, Aleurodicus dispersus (Homoptera, Aleyrodidae) in relation to CBSD incidence in popular cassava cultivars in four cassava growing districts of coastal Kenya. A. dispersus has a wide host range (56) of different food crops, fruit trees, shade trees, ornamentals, weeds and vegetables. CBSD was prevalent in all the districts surveyed with highest incidence being in Msambweni (79.4%) followed by Kwale (68.3%) and Kilifi 64.0%, whereas the lowest (42.8%) prevalence was reported in Kaloleni district. There was a significant positive correlation (r=+0.5189, p<0.001) between number of adult A. dispersus and CBSD incidence. The wide host range affords the whitefly an opportunity to switch hosts presenting a complicated situation for its management. © 2010 Friends Science Publishers