Résumé
The Cocoa Swollen Shoot Virus (CSSV) is a cocoa viral disease transmitted by mealy bugs belonging to the Pseudococcidae family (Dufour, 1988; Lot et al., 1991). These insects live in association with ants and the disease spreads slowly from infected tree to a healthy tree (Dufour, 1991; Castel et al., 1980; Partiot et al., 1978). The most virulent isolates are represented by 'Agou l'in Togo, whose characteristic symptoms are intense red coloration along the secondary veins and limb, discoloration on adult leaves, swelling of stems and branches and stunted pods. Diseased trees wither and die around three years after acquiring the virus creating clearings. This research is conducted in two cocoa areas of Togo (Kloto and Litimé). The main objective is to study the disease dynamics at regional and local level, from satellite images and field observations. The regional scale use information from satellite images to identify and track outbreaks health status of cocoa plantations and also use genetic characterization of virus isolates to determine their spatial distribution in order to study the spatial relation between health status and virus isolates. Partly to a local scale, some plots are studied to understand the pattern of disease spread within plots. (Résumé d'auteur)