Effect of Deficit Irrigation and Mulching on Water Productivity and Yield of Drip-Irrigated Onion (Allium Cepa L.)

The most important component of photosynthesis process in plants is water, whose scarcity can directly affect agricultural production leading to food insufficiency. In a waterlimiting situation, water productivity is maximized whereas incomes are optimized. Water productivity and Onion yields, therefore need to be evaluated through the integrated practice of drip irrigation, deficit irrigation and use of mulches to determine the level of production at which income is optimized. Deficit irrigation (DI), a water management strategy involves the application of limited water supplies during moisture-sensitive crop growth stages or throughout the whole growing season to maximize productivity of the applied water by exposing plants to certain levels of water stress.Both DI and mulching were found to influence the yield and water productivity of bulb onion and other crop growth components to varying degree based on the magnitude of water stress and type of mulch used. For all treatments, it was found that polythene mulched crop gave higher output compared to straw mulched and control treatments. To determineoptimum level of production, economic analysis of the cost-benefit ratio of input and outputcan be conducted.