Study finds large-scale escape of GM canola in US

Wild GM canola plants found in North Dakota with double herbicide resistance; could crossbreed with other plants and weeds

By Ken Roseboro

One of the problems with genetically modified plants is that scientists know how their creations perform in a laboratory but don’t know what they will do when introduced into a complex ecosystem.

“Don’t know what these plants are going to do”

A good example was shown recently by scientists at several US universities who found established populations of GM canola growing in the wild in North Dakota.

“We really don’t know what the consequences are of the gene escape,” said Meredith Schafer, a graduate student at the University of Arkansas. “We don’t know what these plants are going to do.”

The research originated when Schafer and Cynthia Sagers, professor of biological sciences at the University of Arkansas, spotted some yellow flowers in a ditch near Warehouse Foods in Langdon, ND. As part of another research project, they had some portable strips that test for GM proteins found in canola. The strips work much like those in a pregnancy test; Schafer and Sagers crushed plant leaves in water and added the test strip, which would develop one line if it tested negative for the modified gene and two lines if it tested positive for a modified protein. Their test strips could detect the protein that conveys Roundup resistance; they also could detect the protein that conveys resistance to Liberty Link, another herbicide used on canola.

Schafer and Sagers determined at once that the parking lot weeds contained transgenic genes.

“Immediately we knew we needed to investigate it further,” Sagers said.

86% of plants tested positive for GMOs

They filled a car with test strips and set out on a road trip, traveling on highways east and west across North Dakota, stopping every five miles on the highways to look for roadside weeds. They counted canola plants in a 50-meter transect, photographed the locations, took GPS statistics, took a plant sample, and tested the samples. They then collected and pressed the sampled plant and drove to the next location.

“We traveled over 3,000 miles to complete the sampling,” Schafer said. Some of the sites had densely packed plants, with 1,000 specimens in a 50-meter space. They spray these roadsides with herbicides, and canola is the only thing still growing.

They found wild canola in about 46% of the sites along the highway, either growing on the side of the road or in cracks in the highway.

Sagers said some GM plants were growing in the middle of nowhere far from farm fields.

About 90% of the canola grown in the US and Canada is genetically modified according to the Northern Canola Growers Association.

Double herbicide resistance

Of the 406 plants collected, 347 (86%) tested positive for the Roundup herbicide or the Liberty Link herbicide GM traits.

“What we’ve demonstrated in this study is a large-scale escape of a genetically modified crop in the United States,” Sagers told National Public Radio.

Further, some of the plants contained resistance to both herbicides, a combination of transgenic traits that had not been developed in canola crops.

“Varieties with multiple transgenic traits have not yet been released commercially, so this finding suggests that feral populations are reproducing and have become established outside of cultivation,” Schafer said.

Current farming practices may quickly make the problem worse. Each year tens of thousands of acres of canola go un-harvested in the field. As a consequence, an enormous reservoir of seed is created, which can then spread into wild populations.

“Once this happens, it would be difficult to get rid of these weeds using current herbicides,” Sagers said.

Industry reaction was dismissive with the US Canola Association calling the findings “not concerning.”

“Need to be careful what we stick into plants”

Globally, canola can interbreed with 40 different weed species, and 25% of those weeds can be found in the United States.

“There are sexually compatible weeds all over North America,” Sagers said in an interview with Scientific American.

These findings raise questions about the regulation of herbicide resistant weeds and about how these plants might compete with others in the wild.

While the problem looms large in North Dakota, Sagers says the message is a global one. Domesticated plants have wild cousins that often are considered weeds, and sometimes these plants can still cross breed, creating a high potential for herbicide and pesticide resistance to show up where it isn’t wanted.

“Things can escape from cultivation, and we need to be careful about what we stick into plants,” Sagers said.

Sagers told Nature News, UK that regulatory protocols designed to prevent escape and proliferation of wild GM crops are ineffective and that current tracking and monitoring of GMOs are insufficient. She also said there is a lack of funding for research in gene flow.

(Copyright The Organic & Non-GMO Report, September 2010)