Evaluation of Control Methods for Fruit Flies (Diptera: Tephritidae) on Watermelon (Citrullus lanatus (Thumb) Matsum & Nakai) in The Gambia

Abstract
Commercial production of watermelon (Citrullus lanatus (Thunb.) Matsum & Nakai) is increasing in The Gambia, but tephritid fruit flies present a huge challenge to its production. To avoid severe losses, watermelon growers often resort to indiscriminate use of pesticides to manage the pest. Field studies were conducted at two sites (Faraba and Site 3) in the West Coast Region of The Gambia to evaluate two environmentally friendly options (Success Appat (GF-120) and Cocoa Butter Cream) for management of fruit flies on the crop. Dimethoate insecticide, the farmers’ preferred choice, was used as a chemical check and untreated control plots were also maintained. The field plots were arranged in Randomized Complete Block Design and the treatments were replicated three times. The results of the study showed that, even though three species of fruit flies, Bactrocera dorsalis (Hendel), Dacus vertebratus Bezzi and Zeugodacus cucurbitae Coquillett were collected at both study sites, only D. vertebratus infested watermelon fruits. Both Success Appat (GF-120) and Cocoa Butter Cream reduced watermelon fruit infestation and, generally, provided comparable protection as the check (Dimethoate) to watermelon fruits against fruit flies and therefore would be suitable replacements.