Protecting grain from insect pest infestations in africa: Producer perceptions and practices

Abstract

Purpose of review: This review focuses on the current state of postharvest losses and important tools available for use by farmers for protecting grain against insect pest infestations in sub-Saharan Africa with the view of identifying farmer perceptions, effective control practices, critical challenges and information gaps that need further research. Findings: Several beetle and moth pests attack stored grains in Africa causing significant losses. Currently, there is a lack of reliable and verifiable data on postharvest losses in most African countries. Annual grain losses of over 50% in cereals and up to 100% in pulses have been reported. Smallholder farmers have various forms of indigenous knowledge and complex cultural norms which they apply to grain storage practices and their potential effects need to be analysed. Tools available for managing insects associated with grains include contact insecticides and fumigants, botanicals, inert dusts, biological control agents as well as appropriate modified atmospheres through metal silo and hermetic storage technology. The uses of synthetic insecticides continue to be a major component of stored-product pest management strategies in Africa. However, for sustainable grain protection the combination of the various control options in an integrated and compatible manner and their uptake are imperative. Directions for future research: Assessments of the scale of losses for key stored commodities along the value chain are required. For practical utilisation of botanicals well designed on-farm trials are needed to validate their efficacy. Large-scale field assessment of the impact of the histerid predator, Teretrius nigrescens Lewis on the larger grain borer, Prostephanus truncatus (Horn) should be carried out to justify their continued release into the different agro-ecosystems. The current knowledge of triple-bagging technology, its availability and adoption is limited. Appropriate knowledge transfer techniques to encourage adoption of practical techniques needs to be developed. © 2011 Stewart Postharvest Solutions (UK) Ltd.