Rice can do with much less water

Water consumption in rice cultivation can be reduced by 10 to 30 percent if the so-called 'Alternative Wetting and Drying' method is applied, a technique developed by the International Rive Research Institute.

This is badly needed, according to Bas Bouman of IRRI, given the severe droughts in the region. The method also reduces energy consumption and lowers production costs. The technique is already being used in China, India and Vietnam.

The method assumes that a rice field does not have to be constantly under water. There are bamboo tubes underground to measure the water level. When the water is between 5 and 10 cm below the surface, there is enough water for the seedlings. When the water recedes, the farmers pump water into the field. In Bangladesh, water reductions of 30 to 50 percent were achieved in trials and irrigation costs fell by 21 to 27 percent.

Another way to use less water is to plant so-called aerobic rice. It does not need to be submerged in water, but thrives in moist soil. More tests are needed to develop this rice variety, because the yield is 20 to 30 percent lower than that of rice fields that are flooded. The water reduction is nevertheless impressive at 50 percent.

IRRI figures show that a rice field needs two to three times as much water as a field planted with wheat or maize. It takes 1 liters of water to produce 2.500 kilo of rice.
In Thailand IRRI has already experimented with the AWD method in the Northeast and Central regions.

www.dickvanderlugt.nl – Source: Bangkok Post