ABSTRACT
Asia is the biggest producer and consumer of rice in the world. Almost 90 percent of the total world’s rice is produced using irrigation (IRRI, 2003; IRRI, 2009). By 2025, about 15 to 20 million hectares of irrigated rice fields will suffer some degree of water scarcity as a result of climate change and competing water uses (Richards and Sander, 2014), which requires rethinking of the current management practices of rice. Rice grown in a traditional paddy is water intensive and requires between 700–1,500 mm of water per cropping season, depending on soil type and texture (Bhuiyan, 1992). The traditional paddy practice often leads to losses of water via surface run-off, seepage and percolation that accounts for 50–80 percent of total water input (Chapagain and Riseman, 2011). Downstream rice farmers may use part of the lost water through percolation. On top of this, the growing competition for water use for industrial and domestic purposes exacerbates the water scarcity for agricultural use.
