Review on the Role of Integrated Soil Fertility Management in Improving Maize Production in Ethiopia

Abstract

In Ethiopia, the bulk of maize has been produced in humid and mid-altitude agro-ecologies and cultivated continuously on the same piece of land and resulting nutrient depleted soils. To avert low soil fertility problems in the country, commercial fertilizers have been relied to boost the productivity of maize in continuous production system. However, escalating costs of inorganic fertilizers may not encourage the smallholder farmers to use the full dose of fertilizers recommended for their crops. It is thus, to look for another alternative that reduce the cost of production while increasing the productivity of soils. Integrated soil fertility management has been proven to harmonize the current need of smallholder farmers and to produce maize using low input fertilizers from organic sources such as farmyard manure, green manures, compost and also crop rotations. Therefore, several research attempts have been made to optimize the integrated uses of inorganic and organic fertilizers at different locations. At Bako maize rotated with nug and at Jimma maize following soybean reduced the recommended fertilizer rates by 50%. Yearly application of 4 ton FYM ha^-1 with 46/10 kg NP ha^-1gave maize yield comparable to 110/20 kg NP ha^-1 and use of compost also had similar trends at Bako. Uses of legumes such as mucuna and Dolichos lablab at Bako and crotalaria, sesbania and mucuna at Jimma as short fallows and green manures enhanced soil fertility and confirmed to replace either partially or fully the N-fertilizer requirement of maize from external sources. Research reports on integration of crop residues with NP fertilizers at Haramaya and coffee by products integrated with N-fertilizer at Areka could enhance soil fertility and made maize production trends sustainable in Ethiopia. The literatures insights on integrated soil fertility management options for maize production in Ethiopia were reviewed in this paper.

Keywords: Soil Fertility, Organic Fertilizers, Inorganic Fertilizers, Maize, Yield