Deficit Irrigation: A Crucial Tool for Water-Scarce Regions

Insufficient irrigation water supply will not be an exception and irrigation management will shift from emphasizing unit area yield to maximizing unit water consumption, i.e., water productivity. In order to cope with scarce supply, deficit irrigation is an important tool to achieve the goal of reducing irrigation water use. Deficit irrigation is defined as the application of water below the crop's full water requirement ('evapotranspiration'). Although deficit irrigation is widely implemented on millions of hectares of land for various reasons, ranging from inadequate network design to irrigation over-expansion relative to the watershed supply, it has not received sufficient attention in research.