The main effects of gall midges in tropical agriculture are as primary pests of cultivated plants; as predators on pests, especially mealybugs, scale insects and mites; as potential biocontrol agents of weeds and as pollinators of cocoa. Published information is briefly reviewed under these main headings, with particular emphasis on the sorghum midge, Contarinia sorghicola (Coquillett), on the Asian and African rice gall midges, Orseolia oryzae (Wood-Mason) and O. oryzivora Harris & Gagné and on cecidomyiid predators on mealybugs and scale insects.
