Outside a grocery store in Langdon, N.D., two ecologists spotted a yellow canola plant growing on the margins of a parking lot this summer. They plucked it, ground it up and, using a chemical stick similar to those in home pregnancy kits, identified proteins that were made by artificially introduced genes. The plant was GM—genetically modified.
That's not too surprising, given that North Dakota grows tens of thousands of hectares of conventional and genetically modified canola—a weedy plant, known scientifically as Brassica napus var oleifera, bred by Canadians to yield vegetable oil from its thousands of tiny seeds. What was more surprising was that nearly everywhere the two ecologists and their colleagues stopped during a trip across the state, they found GM canola growing in the wild. “We found transgenic plants growing in the middle of nowhere, far from fields,” says ecologist Cindy Sagers of the University of Arkansas (U.A.) in Fayetteville, who presented the findings August 6 at the Ecological Society of America meeting in Pittsburgh. Most intriguingly, two of the 288 tested plants showed man-made genes for resistance to multiple pesticides—so-called “stacked traits,” and a type of seed that biotechnology companies like Monsanto have long sought to develop and market. As it seems, Mother Nature beat biotech to it. “One of the ones with multiple traits was [in the middle of] nowhere, and believe me, there's a lot of nowhere in North Dakota—nowhere near a canola field,” she adds.
That likely means that transgenic canola plants are cross-pollinating in the wild—and swapping introduced genes. Although GM canola in the wild has been identified everywhere from Canada to Japan in previous research, this marks the first time such plants have been shown to be evolving in this way. “They had novel combinations of transgenic traits,” Sagers says. “The most parsimonious explanation is these traits are stable outside of cultivation and they are evolving.”
Escaped populations of such transgenic plants have generally died out quickly without continual replenishment from stray farm seeds in places such as Canada, but canola is capable of hybridizing with at least two—and possibly as many as eight—wild weed species in North America, including field mustard (Brassica rapa), which is a known agricultural pest.