Soil fertility management research for the maize cropping systems of smallholders in Southern Africa : a review

Abstract

This paper examines the implications of declining soil fertility for the maize-based cropping systems in southern and eastern Africa. A review of the importance of maize in the region is followed by a description of the economic and agronomic circumstances of smallholders who produce maize. Next, the paper examines technologies currently available for enhancing soil fertility, including technologies for increasing inorganic/organic fertilizer use and fertilizer-use efficiency and the development of maize genotypes that perform well despite low soil fertility. Ways of facilitating farmers' adoption of better soil fertility management practices are described, based on examples drawn from recent research, particularly in southern Africa. A new model for soil fertility research and extension is proposed. The model features the use of organic as well as inorganic sources of nutrients and actively involves farmers and others in an integrated, long-term process for improving soil fertility in southern and eastern Africa.