Many U.S. farmers now plant crops that contain genes from another species. But from a global perspective such transgenic, or genetically modified, crops remain relatively uncommon around the world, according to a University of Wisconsin-Madison study.

"Many people casually refer to GM or transgenic crop varieties as being the first step in a 'gene' or biotechnology 'revolution,'" says Fred Buttel, the study's author. "They herald this development as the beginning of a global revolution in agriculture."

The numbers, however, do not reveal such a trend, according to Buttel. The co-director of the Program on Agricultural Technology Studies, Buttel has studied how farmers have responded to biotechnology for more than a decade.

"In Wisconsin, the United States and the world as a whole," he says, "the overall pattern of GM adoption is deep in a handful of places and crop sectors. For example, there has been widespread adoption of certain GM crops such as herbicide-resistant soybeans in the American Midwest and
transgenic cotton in the U.S. South and Southwest. However, GM adoption is also narrow in that it has bypassed most of agriculture and is becoming increasingly limited to a handful of commodities in a handful of countries.

"Both proponents and opponents of GM technology need to recognize this contradictory nature of GM adoption to understand the significance of biotechnology in global as well as national terms."
To evaluate global adoption of the technology, Buttel analyzed data taken from a web site maintained by the International Service for the Acquisition of Agri-Biotech Applications. The data covered the period from 1996 to 2001.

"These data are widely cited as the most comprehensive public source of information on the track record of GM crop varieties across the world," says Buttel, who chairs the Department of Rural Sociology at the College of Agricultural and Life Sciences.

"It's clear that the adoption of this technology within the United States has been extraordinary by world and historical standards," he says. "Farmers have adopted transgenic varieties more rapidly than any
agricultural technology in the history of the world. But globally the adoption of transgenic crops has been slow and limited."

The major transgenic crops include herbicide-resistant soybeans, insect-resistant corn, and cotton with one or both of those traits. Transgenic canola, potato and tomato varieties have also been available.

From 1996 to 2001, there was an unprecedented expansion in the acreage of GM soybeans, and to a lesser extent cotton, corn and canola varieties, in three countries - the United States, Canada and Argentina. In 2001, 46 percent of the world's soybean acreage was planted with transgenic varieties, Buttel says. Those three countries account for more than 95 percent of the acreage of GM crops. The United States alone now accounts for almost 70 percent of the world's acreage in GM crops.

Outside of those crops and countries, there are about 5 million acres of transgenic crops. For comparison, that's about the same number of acres that Wisconsin farmers planted to corn and soybeans in 2001.

Because the world's three major food groups are rice, corn and wheat, there is scarcely any real beginning of a "gene revolution" in the world's staple crop sectors, according to Buttel. "Increasingly," he says, "the global diffusion of transgenic varieties is accounted for by one crop - soybean, - in one country - the United States - and by the use of one technology - herbicide resistance."

Globally, soybean has now increased its share of the total GM acreage from less than 20 percent in 1996 to more than 60 percent in 2001. The next largest GM crop is corn. However, the share of the GM acreage in corn and canola has declined during the past 5 years, and GM potatoes and tomatoes never claimed a significant share of the acreage.

Buttel presented his results to a meeting of the Wisconsin Agri-service Association in January.
For a copy of the full report, The Adoption and Diffusion of GM Crop Varieties: The 'Gene Revolution' in Global Perspective, 1996 -2001, contact Nancy Carlisle at (608) 265-2908, nlcarlis@facstaff.wisc.edu.
The publication is also available at http://www.wisc.edu/pats/pubsp.htm the site for the Program's series of staff papers.

Writer: George Gallepp (608) 262-3636

Agricultural and Consumer Press Service College of Agricultural and Life Sciences
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