Abstract

The most difficult problem in the Sahelian countries is drought. In addition, the soils are relatively infertile and acidic. However, it has been found that soil acidity liberates phosphate in the underlying rock and makes it available for crop growth. This project will increase the contribution of rock phosphate fertilizer to food production in Mali. Specifically, it will determine the dissolution characteristics of various phosphates related to rock treatment, crop and climate characteristics, and determine ways of applying results in the region.

Post-Project Summary

To increase food production through the identification of efficient phosphate fertilizers, researchers conducted 29 experiments using sorghum, millet, maize, rice, groundnuts, and cotton at 11 experimental stations. Crop responses to various phosphate fertilizers, including triple superphosphate; Tilemsi phosphate rock (TPR); and partially acidulated phosphate rock developed from TPR, were determined. Four experiments were established to test phosphate sources in various combinations at different rates. Residual effects were measured in subsequent seasons. Researchers found that in areas not limited by rainfall, a basal application of phosphate rock before ploughing gave the largest yield with groundnuts, millet, and sorghum; whereas soluble superphosphate had to be added annually to maize and cotton. It was also concluded that soluble superphosphate gave better responses than phosphate rock in dry areas. It was noted that a preliminary farmer survey in two rural development areas indicated Malian farmers' interest and demand for TPR had increased. Support continued in a second phase.

Recipient Institution(s)