Pest and Diseases


Infected Black Pod Cocoa Tree

The Black Pod is the main disease that is causing significant losses for the cocoa farmers in Sierra Leone. As cocoa is very susceptible to attack by insect pests and fungal diseases.Pod rot also know as Black Pod, is caused by the fungus Phytophthora. Three fungal species of the same genus are responsible causes global yield loss of 20-30% and tree deaths of 10% annually.

The Black Pod usually starts with the rotting or the necrosis of the cocoa pods. The disease can attack the pods at any stage of development, and the initial symptoms are small, hard, dark spots on any part of the pod, internal tissues, these sucking insects damage the soft young tissues of the tree by piercing the young shoots with their mouth parts, injecting poisonous saliva and then sucking liquid food out of the resulting wound.

Pest and disease control is an important component of deliberations at all level in the cocoa sector in the country cocoa production programme and an effective training regime has been put in place by The Produce Monitoring Board (PMB), and also The Agriculture For Development (A4D) project that have employed the service of Agricultural Officers across the country to organize training programme and external workshops.

Understanding how to achieve and maintain healthy soils on cocoa farms is fundamental to sustaining higher yields and lower levels of disease. Severe attack may cause defoliation and subsequent low yields. Attacks are more serious where shade is reduced, so may occur after the death or felling of a forest tree.

Below is table that shows the most common pest and diseases associated with cocoa plantation in Sierra Leone

                         Pest                 Feeding Habits                    Control
    Monkeys and Baboons
  • Destroy flowers and harvest matured rape pods
  • Trap
  • Hunting
  • Farm Hygiene
  • Prick the twigs and the pods
  • Tree dries out and the sap no longer circulates
  • Young trees attacked by capsids of
  • Farm hygiene and other cultural methods
  • Use lindane or Aldrin
  • Larvae of insects bore holes in the trunk or branches
  • Farm hygiene
  • Use of wood ash
  • Cultural method
  • Use of DDT or Dieldrin



The most dangerous diseases that attack cacao trees are the black pod and swollen shoot disease.

    Diseases            Feeding Habit                           Control
Black pod Caused by a fungus which chiefly attacks the pods

  •  The pods rot and die
  •  Pick off diseased pods and burn or bury them off the farm
  • Sound agronomic practices like under brushing, pruning and proper shade management.
  • Spraying the sound pods with copper preparation to prevent disease from spreading.
Swollen-shoot Leaves become mottled

  •  Sometimes some twigs become very thick and the tree soon dies.
  •  Mealy bugs carried about by ants transmit the disease from one tree to another .
  •  Cut down diseased trees and allow them to wither.
  •  When a diseased tree has been discovered and cut down, all trees circling it must be cut down to avoid the spread of infection.