Aphid-borne virus diseases are the most important diseases of cucurbits in the West Indies that cause significant reduction in yield. Surveys of cucurbit farms throughout the West Indies revealed the presence of mosaic, existing in varying degrees of occurrence and severity, as the most predominant disease. The diseases were found to be caused by aphid-borne viruses, either in complexes or individually. Experiments to control the spread of these diseases with emulsion oils in Barbados revealed a six-fold reduction as compared with controls. The oil was applied with CP-3 knapsack sprayer (high volume) using cone jets to zucchini squash in a scheduled spray cycle. Droplet size emitted by the sprayer averaged 20 µm at 36 psi pressure. Rates of application averaged 7.5 ml/l of H2O. Reaping time has been prolonged to more than seven weeks. Fruit quality was improved and crop yield increased. There were no significant differences between disease spread in inoculated and uninoculated plots (P = .05).