Supplemental irrigation/life saving irrigation

Supplemental irrigation (SI) is small amounts of irrigation water given to essentially rainfed crops at their critical stages of growth, particularly when insufficient rainfall or low availability of irrigation water fails to provide adequate moisture for normal plant growth. When rainfall failed to meet water requirement of rainfed crops for stabilized production, SI is applied to prevent crop failure.The SI is not applied to get moisture-stress-free conditions throughout the growing season, rather ensure a minimum quantity of water for getting an optimal production by making moisture available at the critical stages of growth.For instance, about 2 to 3 supplemental irrigation of 5 cm each to rice during critical growth stages (tillering, panicle initiation, milking, and doughing) can enhance yield up to 50%.Water for supplemental irrigation comes mainly from the canal as well as lift irrigation, but shallow groundwater aquifers are also used. One or two supplemental irrigation to rice during dry spell can wipe out drought stress in most of the rice-growing areas of Odisha. If rabi crop is planted in time (by 30 th November), the soil residual moisture is good enough to meet the crop’s requirement.However, when rabi crop is delayed (20 January-15 th February) supplemental irrigation may be needed. If 75-80% of the water requirement is fulfilled by soil moisture, 0-1 irrigation is sufficient. On the contrary, if 55-60% of the water requirement is fulfilled by soil moisture, two irrigations are required for growing low water requiring pulse or oilseed crops.