Agricultural extension is the medium through which external agricultural technologies have been transferred to and transplanted in Africa to improve agricultural performance. Over a period of close to a century, different agricultural extension models have been proposed but their structure and content has virtually been the same - top-down, linear, non-participatory transfer of technology with no feedback loops for reverse diffusion. This presumably explains the poor performance of Africa’s agriculture and the scale of food security challenges facing the continent. In this review paper, we trace the history of agricultural extension and examine various agricultural extension delivery models to identify their major strengths and weaknesses, using Ghana and Burkina Faso as case studies. We then review the most recent literature in the field about the philosophy, scope, content, delivery, and outcomes of agricultural extension. We reach the conclusion that agricultural extension has consistently remained out of sync with the needs and aspirations of stallholder farmers. Smallholder farmers are now calling for new agricultural extension delivery models that are truly farmer-led, indigenous knowledge-based, context-specific, culturally-relevant and environmentally-sustainable to guarantee efficient farming systems into the future.
Keywords: extension delivery, smallholder farmers, indigenous knowledge, top-down, Ghana, Burkina Faso, sustainable agriculture.