R ice (Oryza sativa L.) is one of the most important food crops in the world, and a staple food for more than half of the global population. About 55 per cent of the rice area is irrigated that accounts 75 per cent of the rice production in the world (Bouman and Toung, 2001). In the next 25 years, 15-20 M ha of irrigated rice is projected to suffer from water scarcity particularly wet season irrigated rice in parts of India, China and Pakistan (Carriger and Vallee, 2007). Therefore, for food security, it is essential to ''produce more rice with less water'' (Guerra et al., 1998). Productivity and profitability of transplanted rice is high in Punjab where groundwater is the primary source for irrigation. Floodirrigated rice utilizes two to three times (Toung et al., 2005) more water than other cereal crops such as maize and wheat. However, large amount of water input in rice cultivation has led to over-use of groundwater as indicated by alarming fall (>0.5 meter year -1 ) in water table (Singh, 2009). The rice is transplanted in the month of June when the evaporation rates are high (8-10 mm day -1 ) resulting in a large amount of water consumption. This has led to excessive pumping of water leading to increased pumping cost (Kamra et al., 2002). This raises serious concerns about the sustainability of the rice-based cropping systems in Punjab. The increasing water scarcity for agriculture and competition from nonagricultural sectors indicate an urgent need to search for an alternative technique for growing rice which require less water, and should be technically sound and economically feasible.

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