WASHINGTON, -- Researchers at the International Rice Research Institute (IRRI) have developed a prototype breed of "super rice" that yields 25 percent more food per acre than today's best varieties.


If planted in all suitable parts of the world's rice-growing regions, agronomists estimate it could yield 100 million tons more grain than is now grown -- enough to sustain an additional 450 million people a year.


Moreover, work is underway to modify the variety in a way that promises to achieve another 25 percent boost in yield.


And, according to Klaus Lampe, director general of the Philippines-based institute where the new variety was developed, "super rice" requires significantly less fertilizer per ton of grain than do today's varieties.


"This new rice will go a long way toward feeding the world's people through the next century, especially in Asia where rice is the staple," said Ismail Serageldin, chairman of the Consultative Group on International Agricultural Research.


The CGIAR, funded by 43 governments, international organizations and private foundations, funds IRRI and 16 other research centers dedicated to improving food production in developing countries.


Lampe said plant researchers are cross-breeding the new rice with existing resistant varieties to produce new ones that combine the best traits of the parents. He said that in a year or two, the first of these crosses will be distributed to rice breeders in several parts of the world for further cross-breeding with varieties suited to local soils and climates.


Additional plant breeding is underway to produce subvarieties with the various cooking qualities and flavors preferred by different cultures. These are the kinds of adaptations that are routine with most new varieties of any crop.


Lampe said the new breed is needed because the world has little or no additional land on which to grow rice -- the primary food of the part of the world where the population is growing in the largest numbers.


In fact, some of the best rice land has been lost to urban sprawl. Overall, the area planted in rice worldwide has not increased since 1980.