Diversity of storage insect pests of maize along the maize value chain in three districts of West Nile agro-ecological zone

Abstract

Maize (Zea mays L.) is a critical food and nutrition and livelihood crop in Uganda, particularly in West Nile sub-region. Despite its importance, its production is still low in West Nile sub- region. Post-harvest losses (PHLs) are identified as being the main factor for this low level of total maize production and the primary cause of PHLs is storage insect pests. Research has been focusing on the management of these pests consequently developing a number of management approaches (cultural, biological, chemical and host resistance). However successful control of these insects requires an integrated approach. The purpose of this study was therefore to determine the diversity of these pests and hence their occurrence to design appropriate strategies for integrated pest management (IPM). I also assessed the effect of form of storage on the diversity of the insect pests, farmer’s knowledge and perception, and control measures employed. A survey was conducted in three districts of West Nile sub- region (Koboko, Arua and Nebbi) and samples were collected from farmers, middlemen, traders/stores and processors and then incubated for maximum of two months. Five species were identified including; Prostephanus truncatus, Tribolium sp, Sitophilus sp, Sitotroga cerealella and Ephestia cautella. Farmers in the three districts stored maize in three forms- husked, dehusked and shelled. Modern storage facilities/ materials were not available to farmers and therefore not used. Respondents also had great knowledge of the prevailing insect pests and considered them a big challenge. Sitophilus sp were the most dominant and destructive species and P. truncatus was the least occurring species not identified by the respondents. Generally, diversity of the storage pests varied along the maize value chain with greatest diversity at farmer level and least at traders (urban stores). The form and method of storage and level of chemical use were the factors attributed to the variations in diversity. The following recommendations were therefore made; availing modern storage technologies at affordable prices and education on their use being paramount; IPM strategies that can easily be adopted by farmers should be designed with work on breeding for resistance emphasized to control these pests; participants’ knowledge of the pests and control practices should be used in designing appropriate IPM strategies; manipulation of the method and form of storage as control measure for various insect pests and immediate interventions especially sensitization of the farmers and traders on identification and management of Prostephanus truncatus.