As Asia faces water shortage due to climate change, the ADB and International Rice Research Institute (IRRI) are developing new rice varieties and farming techniques that rely on less water but do not decrease yield productivity.
Alternative wetting and drying
Arvind Kumar, a plant breeder at IRRI, explains a technique called "alternate wetting and drying" (AWD), which uses 15-20% less water without compromise on yield. He said that a "safe AWD" is when water level is allowed to recede to a level 6 inches below the soil surface.
Another is "aerobic rice," a technology for moderate yield capacity that has demonstrated water savings of 30-35%. This could also save farmers on labor cost since aerobic rice is done through direct seeding, wherein tilling is rationalized to conserve soil moisture in the seedbed.
Kumar said that IRRI has already recommended different varieties for aerobic situations in different Asian countries and identified aerobic rice-based crop rotations that have shown high productivity.