Genetic structure and diversity of western flower thrips, Frankliniella occidentalis in a French bean agroecosystem of Kenya

Abstract

Western flower thrips (WFT) (Frankliniella occidentalis) is an introduced pest of French bean first detected in Kenya, presumably in 1989. New WFT management approaches are being developed. The article examines the genetic makeup of WFT populations in Kenya, to uncover the source habitats, crop colonisation patterns, and host plant preferences, as a prerequisite for integrated pest management (IPM) strategies. This article analyses the diversity and gene flow of WFT on French beans, intercrops and weeds in Kenyan French bean production areas. Preliminary results indicate: Kenyan WFT populations have little exchange and show a genetic structure that could lead to development of populations with the same genetic makeup or host races in the future; geographical distance seems to have no effect or only a slight effect on the population structure; and weeds are unimportant as a source for WFT colonising French bean compared to other crop plants. This is an output of the ‘Implementation of Integrated Thrips and Tospovirus Management Strategies in Smallholder Vegetable Cropping Systems of Eastern Africa’ project. It is partly funded by the UK Department for International Development, a core donor of the International Centre of Insect Physiology and Ecology