VOA Special English

This is the VOA Special English Agriculture Report.

One cause of the current food crisis is drought. Food prices are high in part because of dry weather in places as far distant as Spain and Australia.


Australia has been hit hard by drought
Around the world, the amount of land affected by drought has doubled in the past thirty years. So says the National Center for Atmospheric Research in the United States. And scientists concerned about climate change believe it will cause more drought in many areas in the future.

A lot of research is going into efforts to develop drought-resistant crops. One project involves tobacco plants genetically engineered to keep their leaves during water shortages.

Eduardo Blumwald and Rosa Rivero at the University of California, Davis, led a team from the United States, Japan and Israel. Rosa Rivero says they chose tobacco because it has big leaves. Also, it grows fast and has structural similarities with some other plants.

The researchers did an experiment with two groups of tobacco plants. They worked with a set of normal plants and a set of transgenic plants. These had a gene added to interfere with the biological causes of leaf loss during drought.

The researchers put all the plants in a greenhouse to grow under normal conditions for forty days. Then, for fifteen days after that, the plants did not receive any water.

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