Brussels, 12 Aug 2003
Scientists at the University of Bonn in Germany have identified the gene which enables plants to survive droughts. The news is likely to be welcomed by the country's farmers, who estimate that this year's heat wave could mean the loss of up to 80 per cent of their crops.
The researchers began by examining the resurrection plant, native to South Africa. In dry conditions, the plant shrivels up and turns brown, but when rain comes, whether it has been weeks or months, the leaves become green again within the space of a few hours. The plant can lose up to 95 per cent of its water reserves without being harmed. It does this by slowing down its metabolism to almost zero during the dry period.
'By looking at which genetic features are mainly active during periods of drought we are attempting to understand which molecular processes make the plant so hardy,' said Professor Dorothea Bartels, from Bonn's Botanical Institute.
The researchers found that a series of genes is used only during drought periods. They then discovered that one of these genes also exists in mouse-ear cress (Arabidopsis thaliana), a plant indigenous to Germany.
The gene in question contains the structural plan for the detoxification enzyme aldehyde dehydrogenase (ALDH). The Bonn scientists supplied the ALDH gene of the mouse-ear cress with the equivalent of a turbocharger, ensuring that it kicks in much more frequently. The result was that the genetically modified plants not only produced much more ALDH, but they also survived longer periods of drought - 16 days, compared with 12 days for wild mouse-ear cress.
The discovery cold lead to the development of drought-resistant varieties of maize, wheat or soya. With one third of the world's population expected to be living in arid conditions by 2025, such a development may be very welcome.
For further information, please contact:
The University of Bonn
Tel: +49 228 732070