With Ghana exporting $1.28B of Cocoa Beans and $414M Cocoa Paste , it is crucial to highlight the high incidence of diseases that affect cocoa farms. It’s a terrifying situation for a cocoa farmer to see their plantation infected by a deadly disease, which takes years for the symptoms to appear.
Many cocoa farms are the source of livelihood to many farm families and other stakeholders in the cocoa value chain, it is therefore vital that poor farmers who have little or no idea about the symptoms and prevention of these diseases are provided the needed sensitization.
Swollen shoot is unique to West Africa, particularly in Ghana where the disease was first recognized in 1936. It reduces yields on infected trees and eventually kills them. Cocoa swollen shoot virus disease is transmitted by infectious mealybugs and infected budwood that feed on the sap of cocoa plants. The infected spread the virus to adjacent healthy trees by crawling across interlocking branches.
Mealybugs can also infect trees further afield, as they can be transported by wind or by animals, insects and humans. Cocoa swollen shoot virus can infect cocoa plants at any stage of development. The disease causes a wide range of symptoms and its unique to every cocoa variety. Symptoms mostly seen are reddening of primary veins in young leaves, stem and root swellings (some mild strains of the virus do not cause swellings in infected plants) and abnormally shaped pods, usually smaller and spherical.
Since the sighting of this disease in Ghana, it has been managed through the “cutting out and replanting system” with the aim of eradicating sources of inoculum from affected cocoa plantations and replanting with tolerant cocoa hybrids.
From 1985, black pod turned into a major cocoa disease in Ghana. It infects pods, young vegetative shoots, stems and roots of cocoa trees. Black pod is caused by a fungus (Phytophthora) that spreads rapidly on the pods under conditions of excessive rain and humidity, insufficient sunshine, and temperatures below 21 °C (70 °F). On the outside, it begins as a circular brown spot which grows rapidly to cover the entire pod. The infected pods darken to a blackish colour which eventually dries up. To control the spread timely treatment with copper-containing fungicide is required.
Farmers should adhere to policies made for cocoa farmers in growing cocoa regions to minimize the risk of spreading cocoa diseases.