Spatio-temporal distribution of winged adult Aphis gossypii (Hemiptera : Aphididae) in cotton crops (Malvaceae)

The spatio-temporal distribution of cotton plants, Gossypium hirsutum L., i nfested with Aphis gossypii (Glover) winged adults, is described in a plot located in Bangui, Central African Republic. Each cotton plant growing in t he plot was examined visually for a short period of time to ascertain the p resence or absence of A. gossypii and to construct weekly infestation maps. Tests of autocorrelation and dispersion were carried out at different spat ial scales by means of Monte Carlo procedures on embedded counting grids. E dge effect tests were also carried out. The statistical analyses show signi ficant overdispersion of the infested plants and positive spatial autocorre lation. Positive temporal autocorrelation and significant edge effect are d etected intermittently throughout the season.