In releasing their research, the biologists emphasize that the technique, which involves adding genes to synthesize a naturally occurring sugar called trehalose, should satisfy critics of genetically modified foods because the chemical composition of edible parts of plants, such as rice grains, remains unchanged.
The biologists describe the new strategy to help plants overcome three of the main causes of crop failure in Proceedings of the National Academy of Sciences (PNAS ), published the week of Nov. 25, 2002.
"We have demonstrated the feasibility of engineering rice for increased tolerance of major environmental stresses and for enhanced productivity," says Ray J. Wu, Cornell professor of molecular biology and genetics. He is director of a laboratory in the university's College of Agriculture and Life Sciences where stress-tolerant rice has been under development since 1996 with support from the Rockefeller Foundation.
The Cornell biologists showed stress tolerance by introducing the genes for trehalose synthesis into Indica rice varieties, which represent 80 percent of rice grown worldwide and include the widely eaten basmati rice. But the same strategy, they note, should also work in Japonica rice varieties, as well as in a range of other crops, including corn, wheat, millet, soybeans and sugar cane.
The researchers plan to report on their claims of increased food productivity from the resulting transgenic rice plants in a subsequent article. They say the trehalose gene technology will be placed in the public domain -- instead of being sold exclusively to commercial seed companies -- so that improved crop varieties can be cultivated in resource-poor parts of the
Contact: Roger Segelken
Cornell University News Service