A Novel Method For The Control Of Pod Diseases Of Cocoa

Pod diseases of cocoa are widespread in cocoa-growing countries and are responsible for substantial losses in income. Black pod, Moniliophthora pod rot, Witches' broom and Watery pod rot are the major diseases of cocoa pods. The conventional methods of fungicide application by spraying an aqueous suspension using diverse equipment so far yielded only limited control. The drawback of these methods seem to be the inability of the system to release adequate quantities of the chemical during the prolonged rainy spells which are frequent in the tropics. The need for the development of an alternative method for the control of pod diseases was recognized. A new method is being developed at the Cocoa Research Unit, Trinidad. Copper fungicides were placed in a collar-like device and attached to the top of the main trunk or branches of cocoa trees. The water flow from rains passes through the collar permitting a slow release of the fungicide during rainy periods. This guarantees the availability of fungicide in sufficient concentration to prevent pod infection during the prolonged rainy spells. Preliminary studies on Black Pod disease have shown very significant reduction in pod losses when collars with log or 5g a.i. were used.