26 November 2002

GM technique will improve rice yield

By Roger Highfield, Science Editor

A new way to alter rice and other crops genetically to make them more tolerant of drought, salt and low temperatures, while boosting yields, is unveiled today.

The development will alarm anti-GM green groups but the Cornell University team that made the breakthrough emphasises that the technique, should satisfy critics because the chemical composition of the edible parts of the plants, such as rice grains, remains unchanged.

The technique, which involves adding genes to make a naturally-occurring sugar called trehalose, is described in the Proceedings of the National Academy of Sciences.

The new strategy is aimed at helping plants to overcome three of the main causes of crop failure in the Third World. Prof Ray Wu said: "We have demonstrated the feasibility of engineering rice for increased tolerance of major environmental stresses and for enhanced productivity.

The Cornell biologists introduced the genes for trehalose synthesis into Indica rice varieties, which represent 80 per cent 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 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 poorer parts of the world where the need is greatest.