ABSTRACT
The role of insect pests and their capability of destroying more than half of the kolanuts produced cannot be over-emphasized. The kola weevils are field-to-store pests as their infestation is initiated in the field and persists in storage. All the kola trees in Africa are believed to be infested with a significant infestation of 30% to 70%, which can be as high as 100% in some cases of late harvest. The weevil infestation also predisposes the nuts to secondary invasion by other micro-organisms, especially fungi which altogether lowers the market value and may eventually result in the destruction of the nuts. The use of synthetic insecticides in the control of kola weevils in storage has been discouraged due to its high persistence, poor knowledge of application, increasing costs of the application, pest resurgence and lethal effects on non-targeted organisms in addition to direct toxicity to users. Unfortunately, since kolanuts are consumed in raw form without any further post-harvest processing, chemical control of weevils is highly unacceptable due to the probable high level of residue in the treated nuts and the possible long-term effect of these residues on consumers.
