Rice is the staple food in Asia and is the single biggest user of freshwater. It is mostly grown under submerged soil conditions and requires much more water compared with other crops. The declining availability and increasing costs of water threaten the traditional way of growing rice under irrigated conditions. Moreover, the lack of rainfall is a major production constraint in rainfed areas where many poor farmers live. Efficiency in the use of water is critical to help reduce poverty and safeguard food security in water-scarce areas in Asia.

Water requirements can be lowered by reducing water losses due to seepage, percolation, and evaporation. Promising technologies include saturated soil culture and intermittent irrigation during the growing period. However, these technologies still use prolonged periods of flooding, so water losses remain high. A fundamentally different approach is to grow rice like an upland crop, such as wheat, on nonflooded aerobic soils, thereby eliminating continuous seepage and percolation and greatly reducing evaporation. Traditional upland rice has been bred for the unfavorable uplands to give a stable, though low, yield with minimal external inputs. Previous experiments of growing high-yielding lowland rice under aerobic conditions have shown great potential to save water but it has severe yield penalty. A new type of rice is needed to achieve high yields under high-input aerobic conditions.

In northern China, breeders have produced first-generation temperate aerobic rice varieties with a yield potential of 6 tons per hectare using only 50% of the water used in lowland rice. In the tropics, first-generation aerobic rice varieties are now being produced and initial management recommendations are being developed. A shift from continuously flooded to aerobic conditions may have profound effects on soil health, long-term sustainability, and environmental parameters.

A collaborative project on new water-saving rice technologies, specifically aerobic rice, is being developed for Bangladesh, India, Nepal, and Pakistan. In South Asia, it has been estimated that, by 2012, 12 million hectares of irrigated rice may suffer from severe water shortage, seriously affecting the region's food security and social stability.