The effects of Decis® (deltamethrin) and Systoate® (dimethoate) were assessed by the number of Megalurothrips sjostedti (Trybom) (Thysanoptera, Thripidae) recorded per cowpea plant at 40, 50, 60 and 70 days after planting (DAP), evaluated by the drop-cloth sampling method. The trial was carried out under natural infestation conditions during the 1985 early cropping season (from April to July). Systoate® was better than Decis® in controlling the flower thrips and its effect was significantly different from the unsprayed control (P = 0.01). The Decis® effect on the flower thrips was also effective in comparison with the control (P = 0.01). The effectiveness of two insecticides used in relation to pest management and the adequacy of the drop-cloth sampling method in relation to other methods are discussed.
