Rice uses 34 to 43 per cent of the global irrigation water and is responsible for the withdrawal of 24 to 30 per cent of the of World’s total freshwater. In Asia, irrigation consumes greater than 80% of the freshwater resources available and among that rice irrigation accounts for more than 50%. The amount of water applied to produce 1 kg of rice ranges from 800 to 5000 liters, with an average value of about 2500 liters. Earlier studies indicated that seasonal water requirement for rice ranged from 660–5280 mm depending on the climatic features growing season, hydrological framework and type of soil conditions, with the average value range from 1000– 2000 mm as a mean value in most cases. Several approaches of water saving techniques such as, AWD- Alternate Wetting and Drying, SSC- Saturated Soil Culture, aerobic rice, ground-cover systems, SRI- System of Rice Intensification, raised beds, etc. are discussed in lieu of frequent occurrence of extreme weather events and depleting water resources globally. Climate change and variability alters the water requirement, a simulation study by CROPWAT for temperature increase from 0.5 to 3.0⁰ C resulted in an increase in the irrigation water requirement from 0.6 to 3.7%, respectively. Future climate models showed that the rice growing area and yield of paddy tends to have a minor increase (1.55%) in some of the RCPs. Adopting innovative water saving techniques are absolutely essential for maintaining the food security (future rice production) due to increasing water scarcity under the changing climate scenario. Water savings in rice farming through different approaches are discussed and even adoption of any of these practices will transform into saving of larger quantity of water, since huge quantities of fresh water is used for rice cultivation. Because of the continuously depleting water table due to natural and anthropogenic factors, here we have explored to exploit the potentials of various water-saving approaches and the strategies for improving the water productivity along with the improved yield of rice in this review.

稻米消耗了全球灌溉水的34％至43％，是世界淡水总量的24％至30％的抽取者。在亚洲，灌溉消耗了超过80％的淡水资源，其中水稻灌溉占了50％以上。生产1公斤大米所需的水量为800至5000升，平均约为2500升。较早的研究表明，水稻的季节性需水量在660-5280毫米之间，具体取决于生长期的气候特征，水文框架和土壤状况的类型，多数情况下平均值为1000-2000毫米。节水技术的几种方法，例如AWD（交替湿润和干燥），SSC（饱和土壤）培养，需氧稻米，地被植物系统，讨论了水稻集约化强化系统，高架床等，以代替极端天气事件的频繁发生和全球水资源的枯竭。气候变化和多变性改变了需水量，CROPWAT对温度从0.5升高到3.0的模拟研究⁰C导致灌溉水需求量从0.6分别增加到3.7％。未来的气候模型表明，在某些RCP中，水稻的种植面积和稻谷产量趋于小幅增长（1.55％）。由于不断变化的气候情景下水资源短缺，采用创新的节水技术对于维持粮食安全（未来大米的生产）绝对至关重要。讨论了通过不同方法在水稻种植中节水的方法，甚至采用这些方法中的任何一种都将转化为节水，因为大量的淡水用于水稻种植。由于自然和人为因素导致地下水位不断枯竭，