Experts to tweak plant genes to boost yield by half and cut water and fertiliser needs
Alastair McIndoe, Straits Times 1 Feb 09;
Manila - Crop scientists call it supercharging the rice engine.
The International Rice Research Institute (IRRI) in the Philippines is launching a far-reaching project to boost rice yields by 50 per cent or more through genetic engineering to meet future demand for the staple food from rising populations.
It centres on re-engineering rice's photosynthesis - the means by which plants derive energy to grow - which the IRRI's scientists say has the potential to usher in nothing short of a new Green Revolution in Asia, the world's rice bowl.
A US$11 million (S$17 million) funding from the Bill and Melinda Gates Foundation has got the project rolling.
IRRI has formed a network of the world's experts on photosynthesis, including scientists from the universities of Oxford and Yale, for the task ahead. They are set to meet in April at IRRI's headquarters in Los Banos to draw up a research-and-development roadmap.
Last year's rocketing rice prices put the spotlight on whether Asia would be able to grow enough rice in the future because there are limitations to increasing production using current technologies.
Land for growing rice is getting scarcer across the region from creeping urbanisation and other uses. Simply put, Asia needs much more rice from less land.
The IRRI estimates that by 2050, rice production must rise by 50 per cent in Asia going by the region's current trend of population growth and rice output.
'We have a huge problem and superior photosynthesis is perhaps the only mechanism that can solve it,' said Dr John Sheehy, who heads the project at the IRRI.
Unlike rice, crops such as maize and sorghum have more effective systems of photosynthesis, enabling them to produce higher yields. These are called C4 plants, since they initially form a molecule with four carbon atoms during photosynthesis. Rice is classified as a C3 plant, with a less effective photosynthesis mechanism.
Scientists on the project aim to identify the C4 gene in maize and sorghum, and then construct genetic material from those plants that can be used to modify rice.
It will likely take at least a decade to produce a prototype rice plant, and another five years before C4 rice seeds reach farmers. On paper at least, C4 rice would not only significantly boost yields, but also need less water and nitrogen fertiliser.
'Considering that more than 90per cent of the world's rice is consumed within Asia and is the major staple for hundreds of millions of poor - and often undernourished - people, improving the efficiency of photosynthesis in rice would have an enormous impact,' said the IRRI's spokesman Duncan Macintosh.
What is more, added Dr Sheehy, 'the genes that we discover and construct for C4 rice can be put in other crops, such as wheat in Africa in dryland areas, helping to increase their production as well'.
The debate over genetically modified (GM) crops is as heated as ever, especially in Europe. Among the concerns is the ethical opposition to 'playing with nature'.
But the technology has been used to help crops better adapt to pests, disease and harsh environments. The biotech lobby also believes GM crops, such as pro-Vitamin A 'golden rice' that is being developed by the IRRI and others, can play a vital role in combating world hunger.
'I understand the concerns about some GM techniques, such as injecting an alien protein into rice; that would require caution,' said Dr Sheehy. 'But with the photosynthesis mechanism we don't need to do that. All we are doing is working to produce more carbohydrate and energy.
'C4 rice would be no more dangerous than mixing Rice Krispies and cornflakes in the same bowl.'
About 100 scientists from IRRI and universities and research institutions in Australia, Britain, Canada, Germany and the United States will work on the project.
The cost of producing a commercial variety of C4 rice is estimated at US$120 million.
'We're hoping for some early successes to encourage the Gates Foundation and national science councils in Asia to commit to larger amounts,' said Dr Sheehy.
