Systemic Insecticides for the Control of Insects transmitting Swollen-shoot Virus Disease of Cacao in the Gold Coast

Abstract

The swollen-shoot virus of cacao is transmitted in the Gold Coast by mealybugs, of which Pseudococcus njalensis Laing is the most important, and these are tended by ants of the genus Crematogaster, which build carton tents over the colonies, thus affording them protection against contact insecticides. An account is given of an investigation which was carried out at Tafo, Gold Coast, between 1950 and 1953, of the possibility of controlling mealybugs and thus the spread of the virus, by the use of systemic insecticides. Dimefox, schradan, paraoxon and parathion were tested, although the two last are not strictly systemic in action.