access to irrigation reduces the risk of crop failure encouraging the adoption of higheryielding varieties of food crops diversification into highervalue cash crops application of fertilisers and pest management and intensification of farm labour and practices van koppen et al according to the world development report world bank irrigated land does not exceed of total agricultural land in subsaharan africa compared with in east asia and in south asia in areas where farmers mostly rely on rainfed agriculture water availability is one of the most binding constraints on agricultural production