A nondescript grass discovered in the Oregon countryside is hardly an alien invasion. Yet the plant - a genetically modified form of a grass commonly grown on golf courses - is worrying the US Department of Agriculture (USDA) enough that it is running its first full environmental impact assessment of a GM plant.I live in Oregon and I remember many objections to this project when it was started years ago. The danger with this and all other genetically modified organisms is there is no way to know what the impact will be in the wild or the impact on agriculture.
It is the first time a GM plant has escaped into the wild in the US, and it has managed it before securing USDA approval. The plant, creeping bentgrass (Agrostis stolonifera, carries a bacterial gene that makes it immune to the potent herbicide glyphosate, better known as Roundup. The manufacturer, The Scotts Company, Marysville, Ohio, is hoping the grass will provide a turf that makes it easier for golf course owners to manage their fairways and greens by letting them kill competing weedy grasses with glyphosate.
Bentgrass is a perennial, so once out there it regrows year after year, whereas most GM crops - mainly soybeans, maize and canola (oilseed rape) - are annuals, unable to reproduce, harvested each year and replaced with an entirely new crop the next. Another worry is that unlike the other GM crops, bentgrass has many relatives in the US with which it can cross-breed or hybridise, potentially passing on the glyphosate-resistance gene to other species - with unpredictable results.
"It's a cautionary tale of what could happen with other GM plants that could be of greater concern," says Reichman. "I suspect that more examples of this will show up." His report will appear in the October issue of Molecular Ecology.
"It's definitely a new set of variables we've not had to deal with in previous GM crops," says Eric Baack of Indiana University in Bloomington, who comments on Reichman's findings in Current Biology (vol 16, p R1). Still, it isn't clear whether the gene would have much impact in the wild. "You wouldn't expect the weedkiller-resistance gene to be a particular advantage in the wild," says Baack. Also, the USDA doesn't class conventional bentgrass as a "noxious" weed.
There is however the possibility of litigation if the GM grass contaminates other elite grass strains under cultivation. Some 70 per cent of the US's commercial grass seed is grown in Oregon, so there is the potential for accidental adulteration.