Hanna, A.D., & Heatherington, W. 1957 Arrest of the swollen shoot virus disease of cacao in the Gold Coast by controlling the mealy bug vectors with the systematic insecticide Dimefox.. Annals of Applied Biology 45(3): 473-480.
Notes: A 13-acre plot of cacao, in an area devastated by swollen shoot, was treated by dimefox applied to the soil nine times. Mealybug species transmitting the virus were identified as Pseudococcus njalensis, P. citri and Ferrisia virgata. The plot was examined every month and trees recorded as they showed symptoms. The number of such trees decreased very rapidly a year after the first treatment and remained low for the three years that the experiment was continued. This suggests that the time between infection and symptom development can extend to about 1 year. The cause of the continued appearance of a few diseased trees could not be determined. Chemical treatment combined with cutting out was more efficient than cutting out alone.