Rice breakthrough promises secure future supplies

A major global scientific effort to enhance the efficiency of rice could have important implications in the supply of the world's most important food.

Experts are working on converting rice from being a C3 plant to a C4 plant, where the 'C' refers to the carbon captured by photosynthesis for growth.

The more solar energy a rice plant can efficiently capture, the more it will yield.

"We need to meet the challenge of feeding a growing world population which is projected to reach 8.3 billion in 2030 with an accompanying rice demand of 771 million tonnes," said the International Rice Commission secretary Nguu Nguyen.

In order to meet this expected demand for rice in 2030, Nguyen said that global rice production 618 million tonnes in 2005 would need to increase by about 153 million tonnes.

"This is an enormous challenge as land and water resources available for rice production keep diminishing as a result of urbanisation and industrialisation," he said.

Rice is the primary food for more than three billion people around the world. Approximately one-fourth of the global rice crop is grown in rain-fed lowland plots that are prone to seasonal flooding.

These seasonal flash floods are extremely unpredictable and may occur at any growth stage of the rice crop.

But Nguyen said that C4 rice could have the potential to out-yield the best performing existing rice varieties and hybrids by 15 to 20 per cent. However, it will take several more years before the C4 rice varieties may become available.

"And, then we will have to make sure that they are safe for human and animal consumption as well as for the environment," he said.

The future of rice production therefore looks positive. The major historic breakthrough that has allowed scientists to propose such solutions as C4 was the successful mapping of the rice genome in 2002, which created new opportunities for the application of genetic resources for breeding new generation of rice varieties.

However, concerns related to bio-safety, conservation of rice genetic diversity and intellectual property rights remain. These will have to be dealt with before C4 rice becomes a reality.