A new study shows that genes from genetically engineered grass can spread much farther than previously known, a finding that raises questions about the straying of other plants altered through biotechnology. Critics worry that the grass, a form of creeping bentgrass developed to be resistant to Roundup, the most widely used weedkiller, could spread to areas where it is not wanted or transfer its herbicide resistance to weedy relatives, creating superweeds that would be immune. The U.S. Forest Service said this year that the grass "has the potential to adversely impact all 175 national forests." Some scientists said the new results, published online Monday by the journal Proceedings of the National Academy of Sciences, did not necessarily raise alarms about existing genetically modified crops like soybeans, corn, cotton and canola. There are special circumstances, they say, that make the grass more environmentally worrisome, like its extraordinarily light pollen.
The study raises concerns for Monsanto and Scotts, two companies that are seeking approval for their new bioengineered grass. They say their altered grass would allow groundskeepers at golf courses to spray the herbicide on their greens and fairways to kill weeds while leaving their bentgrass unscathed.
Because Scotts has plans to develop other varieties of bioengineered grasses for use on household lawns, the new findings could have implications well beyond the golf course. And the study suggests that some previous studies of the environmental impact of genetically modified plants have been too small to capture the full spread of altered genes.
Scotts says that because naturally occurring bentgrass has not caused major weed problems in the wild, the bioengineered version would pose no new hazards.
And any Roundup-resistant strains that might somehow develop outside of intentionally planted areas could be treated with other weedkillers, the company said.
Because of the environmental questions, the application for approval of the bioengineered bentgrass is encountering delays at the U.S. Department of Agriculture, which must decide whether to allow the plant to be commercialized. After hearing public comments this year, the department has decided to conduct a full environmental impact statement, which could take a year or more, according to Cindy Smith, who is in charge of biotech regulation.
Grass Study Adds to Worry on Genes
Genetically engineered bentgrass may be spreading further than originally thought.