In arid and semiarid regions and under rainfed conditions, water availability is one of the principal ecological constraints that hinder agriculture’s sustainability. The super absorbent polymer (agricultural) is water-absorbing and is cross-linked to absorb aqueous solutions through bonding with water molecules. It is a new approach to water management under water-stressed conditions to conserve soil moisture in the active rooting zone of crops by reducing the evaporation, deep percolation, and runoff losses. Agricultural hydrogels are water retention granules which swell their original size to numerous intervals when they come in contact with water. It can absorb and retain a huge amount of moisture under plentiful rainfall and irrigation events and release it back to the soil for mitigating crop water demand when the rhizosphere zone dries up under drought conditions. It plays multifarious roles in agriculture including soil-water retainer, nutrient and pesticide carriers, seed coating, soil erosion reducer, and food additives. It has the extraordinary ability in improving different physicochemical, hydrophysical, and biological properties of soil, simultaneously decreasing irrigation frequency, enhancing the water and nutrient use efficiencies, and increasing the yield and quality of the field, plantation, ornamental, and vegetable crops. These biodegradable materials are nontoxic to the soil, crop, and environment. Hence, the addition of the hydrogel polymer will be a promising and feasible technological tool for augmenting crop productivity under moisture stressed conditions.

Optimization of water and nitrogen is vital for gladiolus production. Field experiments were carried out during rabi seasons of 2012-13, 2013-2014 and 2014-15 to evaluate the four irrigation regimes (gravityfed drip irrigation schedule at 0.6, 0.8 and 1.0 of pan evaporation replenishment, E0 including surface irrigation as control) and three settings of nitrogen nutrition (100% RDN as vermicompost, 50% RDN as vermicompost + 50% RDN as fertilizer and 100% RDN as fertilizer) on gladiolus cv. American beauty. The results showed that under assured irrigation water supply, maximum spike and corm yields, gross return, net return and BCR (3.44) was obtained with optimal drip irrigation at 1.0 E0 with 50% RDN as vermicompost + 50% RDN as fertilizer. However, under limited irrigation water supply, moderate deficit drip irrigation at 0.8 E0 with 50% RDN as vermicompost + 50% RDN as fertilizer was found most viable alternative in deriving higher yields, gross return, net return and BCR (3.32). Under water scarce, reasonable good yields, gross return, net return and BCR (2.62) was accomplished with higher deficit drip irrigation at 0.6 E0 with 50% RDN as vermicompost + 50% RDN as fertilizer. The findings highlight the techno-economic feasibility of low-cost gravity drip irrigation and nitrogen management for efficient utilization of available groundwater and nitrogen resources for profitable gladiolus cultivation in Gangetic alluvial plains of eastern India.

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