A Review of the Effect of Deficit Irrigation and Mulching on Yield and Water Productivity of Drip Irrigated Onion

Water is the most important substrate of the photosynthesis process and its scarcity directly limits growth of plants hence agricultural production. In a water limiting scenario, water productivity is maximized whereas incomes are optimized. Water productivity and Onion yields therefore, needs to beassessed through integrated practice of drip irrigation, deficit irrigationanduse of mulches to determine the level of production at which income is optimized. Deficit irrigation involves exposing plants to certain levels of water stress during either a particular growth period or throughout the whole growth season. The optimum level of production can only be obtained by conducting an economic analysis of cost-benefit ratio of input and output.