Air Date: Week of August 3, 2001

Living on Earth's Maggie Villiger reports on a genetically modified tomato plant that can withstand salty soil.

Transcript

CURWOOD: Just ahead, sound ecology, how Nature shares the spectrum. First, this technology note from Maggie Villiger.

VILLIGER: Most plants can't grow in environments that are very salty, but over a quarter of the world's irrigated farmland is salty enough to limit agricultural productivity. Salt builds up in soil when irrigation is used extensively in arid or semi-arid climates where evaporation is high and drainage is low. So scientists have been trying to develop crops with high salt tolerance, in order to take advantage of these less than ideal habitats. Salt tolerance is thought to be a complex trait that involves multiple genes. But recently, researchers discovered a way to use a single gene to produce plants that can thrive in salty conditions. They took a typical tomato plant, and introduced the DNA sequence that contains a particular gene from the Arabidopsis plant, a member of the mustard family. The gene codes for a protein that pumps excess salt out of cells. The resulting genetically modified tomato plant was able to remove its excess salt by pumping it into compartments in its leaves. These tomatoes flourished, in conditions that would have killed or stunted normal tomato plants. In addition, while their leaves contained high concentrations of sodium, their fruit had very little extra salt. Scientists believe this discovery may allow for greater use of the world's salty soils as other salt-tolerant crops are developed. That's this weeks Technology Note. I'm Maggie Villiger.

CURWOOD: And you're listening to Living on Earth.

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