Potential Utilization of Local Phosphate Rocks to Enhance Rice Production in Sub-Saharan Africa

Abstract

It is known that phosphate rock (PR) deposits that account for most world′s PR production are found in African countries. However, the rate of phosphorus (P) fertilizer use in Africa is typically low, despite the high requirement for application of the same there. This applies particularly to sub-Saharan Africa (SSA), where P deficiency has been suggested as one of the key constraints to crop production, despite the many PR deposits. There have been many excellent reviews on PR utilization in SSA, but hardly any have focused on its effectiveness in lowland rice cultivation. Given this lack of information, we reviewed the potential of PRs produced in the SSA region, focusing particularly on the utilization of PRs for rice cultivation in this region. Our review indicates that PR direct application in lowland rice resulted in high performance, regardless of the PR reactivity and the location investigated. A Phosphate Rock Decision Support System can help disseminate information on PR utilization in SSA; however, there is room for further improvement in predicting agronomic efficiencies in lowland rice cultivation, with consideration of the unique changes in soil condition such as the reduced condition that occurs in submerged paddy soils. In conclusion, the local PRs produced in SSA can be effectively utilized for direct application on lowland rice cultivation, hence the need to elucidate the PRs solubilization mechanism and therefore clarify the condition that maximizes the effect of local PRs direct application in SSA.