Spatial variation in cocoa insect pest populations and its implication for pest management

ABSTRACT

Currently, mirids, stink bugs and coreid bugs are the most important insect pests of cocoa in Ghana. The populations of these insect pests are known to be influenced by the availability of food and breeding sites, as well as the macro and micro climates in cocoa farms. The study investigated variations in the population dynamics of these pests and their damage trends within a square mile (259 hectares). Pest numbers and damage were assessed monthly on 100 trees per plot from 2015 to 2020, each plot measuring one acre (0.4 hectare).   Significant differences (p < 0.05) were observed in pest numbers and damage symptoms of the different pest species for the various months of assessment. Populations of each pest species (mirids, stink bugs and the coreid bugs) and their associated damage in the various cocoa plots were significantly different (p < 0.05). The study showed that relying on the pest activity in one cocoa plantation to determine pest management activities in a nearby cocoa plot may not always lead to accurate and effective pest control. The need for pest surveillance and monitoring at the farm level as a basis to design effective Integrated Pest Management in cocoa production is discussed.

KEYWORDS:

• Mirid
• stink bugs
• coreid bugs
• population dynamics
• pest surveillance and monitoring

Acknowledgements

The authors are grateful to Phebe Tagbor, Wisdom Baku, Richard Edem Banini and Ruben Ofori from the Entomology Division and Godwin Kwame Addo and Nsor Atibila from the Agronomy Division for their involvement in data collection during the study period. The authors are also grateful to Dr. Owusu Domfeh (Plant Virologist) for proof reading the manuscript. The paper is published with the permission of the Executive Director of the Cocoa Research Institute of Ghana (CRIG) (CRIG/03/2023/009/010).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1. Chupons: basal shoots.