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Genes from engineered grass spread for miles, study finds (Tuesday, Sept. 21, 2004 -- CropChoice news) -- Andrew Pollack, NY Times: The two companies, Monsanto and Scotts, have developed a strain
of creeping bentgrass for use on golf courses that is resistant to
the widely used herbicide Roundup. The altered plants would allow
groundskeepers to spray the herbicide on their greens and fairways
to kill weeds while leaving the grass unscathed. But the companies' plans have been opposed by some
environmental groups as well as by the federal Forest Service and
the Bureau of Land Management. Critics worry that the grass could
spread to areas where it is not wanted or transfer its herbicide
resistance to weedy relatives, creating superweeds that would be
immune to the most widely used weed killer. The Forest Service
said earlier this year that the grass "has the potential to adversely
impact all 175 national forests and grasslands." Some scientists said the new results, to be published online this
week 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 creeping
bentgrass more environmentally worrisome, like its extraordinarily
light pollen. 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, 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 weed killers, the company said. In the new study, scientists with the Environmental Protection
Agency found that the genetically engineered bentgrass pollinated
test plants of the same species as far away as they measured -
about 13 miles downwind from a test farm in Oregon. Natural
growths of wild grass of a different species were pollinated by the
gene-modified grass nearly nine miles away. Previous studies had measured pollination between various types
of genetically modified plants and wild relatives at no more than
about one mile, according to the paper. "It's the longest distance gene-flow study that I know of," said
Norman C. Ellstrand, an expert on this subject at the University of
California, Riverside, who was not involved in the study but read the
paper. "The gene really is essentially going to get out," he added. "What
this study shows is it's going to get out a lot faster and a lot
further than people anticipated." One reason the grass pollen was detected so far downwind was
the size of the farm - 400 acres with thousands of plants. Most
previous studies of gene flow have been done on far smaller fields,
meaning there was less pollen and a lower chance that some
would travel long distances. Those small studies, the new findings
suggest, might not accurately reflect what would happen once a
plant covers a large area. "This is one of the first really realistic studies that has been
done," said Joseph K. Wipff, an Oregon grass breeder. Dr. Wipff
was not involved in the latest study but had conducted an earlier
one that found pollen from genetically engineered grass traveling
only about 1,400 feet. That test, though, used less than 300 plants
covering one-tenth of an acre. The effort to commercialize the bentgrass has attracted attention
because it raises issues somewhat different from those
surrounding the existing genetically modified crops. It would be the first real use of genetic engineering in a suburban
setting, for example, rather than on farms. And the grass is
perennial, while corn, soybeans, cotton and canola are planted
anew each year, making them easier to control. Bentgrass can also cross-pollinate with at least 12 other species of
grass, while the existing crops, except for canola, have no wild
relatives in the places they are grown in the United States. And
crops like corn and soybeans have trouble surviving off the farm,
while grass can easily survive in the wild. The bentgrass, moreover, besides having very light pollen - a cloud
can be seen rising from grass farms - has very light seeds that
disperse readily in the wind. It can also reproduce asexually using
stems that creep along the ground and establish new roots, giving
rise to its name. Because of the environmental questions, the application for
approval of the bioengineered bentgrass is encountering delays at
the Department of Agriculture, which must decide whether to allow
the plant to be commercialized. After hearing public comments earlier this year, the department
has now decided to produce a full environmental impact statement,
which could take a year or more, according to Cindy Smith, who is
in charge of biotech regulation. Ms. Smith, in an interview yesterday, said the new study "gives
some preliminary information that's different from previous studies
that we're aware of." But more conclusive research is needed, she
said. Bentgrass is already widely used in its nonengineered form by golf
course operators, mainly for greens but also for fairways and tee
areas, in part because it is sturdy even when closely mown. It is
rarely used on home lawns because it must be cared for
intensively. And creeping bentgrass does not cross-pollinate with
the types of grass typically used on lawns, scientists said. Executives at Scotts, a major producer of lawn and turf products
based in Marysville, Ohio, said the genetically engineered
bentgrass would be sold only for golf courses. They said golf
courses cut their grass so often that the pollen-producing part of
the plants would never develop. And because nonengineered creeping bentgrass has not caused
weed problems despite being used on golf courses for decades,
they said, the genetically modified version would pose no new
problems. "There has been pollen flow but it has not created weeds," Michael
P. Kelty, the executive vice president and vice chairman of Scotts,
said in an interview yesterday. He said Scotts and Monsanto, the
world's largest developer of genetically modified crops, had spent
tens of millions of dollars since 1998 developing the bioengineered
bentgrass. The questions about the grass come after Monsanto, which is
based in St. Louis, said earlier this year that it was dropping its
effort to introduce the world's first genetically engineered wheat,
citing concerns by farmers that its use in foods might face market
opposition.<.p>
Scotts is also developing genetically modified grass for home
lawns, like herbicide-tolerant and slow-growing types that would
need less mowing. But those products still need several more
years of testing, Dr. Kelty said, adding that the company would
avoid types of grass that could become weeds. "We don't want to
put a product out there that is going to be a threat," he said. Scotts and Monsanto have received some support for their
argument from the Weed Science Society of America, a
professional group, which conducted a review of the weed
tendencies of creeping bentgrass and its close relatives at the
request of the Department of Agriculture. "In the majority of the country these species have not presented
themselves as a significant weed problem, historically," said Rob
Hedberg, director of science policy for the society, summarizing
the conclusions of the review. He said that because people have
generally not tried to control bentgrass and similar species with
Roundup, known generically as glyphosate, "the inability to control
them with this herbicide is a less significant issue." Still, the society's report noted that bentgrass could be considered
a weed by farms that are trying to grow other grass seeds. And the
Forest Service, in comments to the Agriculture Department earlier
this year, said that bentgrass has threatened to displace native
species in some national forests. John M. Randall, acting director of the Invasive Species Initiative at
the Nature Conservancy, said bentgrass and related species had
been a threat to native grasses in certain preserves that the group
helps manage, including a couple near Montauk Point on eastern
Long Island. Other opponents of the genetically modified grass seized on the
results. "This does confirm what a lot of people feared - expected,
really," said Margaret Mellon, director of the food and environment
program for the Union of Concerned Scientists in Washington.
"These kinds of distances are eye-popping." The new study was done by Lidia S. Watrud and colleagues at an
E.P.A. research center in Corvallis, Ore., who were trying to
develop new methods to assess gene flow, not specifically to study
the bentgrass. They put out 178 potted and unmodified creeping bentgrass plants,
which they called sentinel plants, at various distances around the
test farm. They also surveyed wild bentgrass and other grasses.
They collected more than a million seeds from the plants, growing
them into seedlings to test for herbicide resistance and doing
genetic tests. The number of seeds found to be genetically engineered was only 2
percent for the sentinel plants, 0.03 percent for wild creeping
bentgrass and 0.04 percent for another wild grass. Most of those
seeds were found in the first two miles or so, with the number
dropping sharply after that. Still, said Anne Fairbrother, one of the
authors of the report, finding even some cross pollination at 13
miles "is a paradigm shift in how far pollen might move." Source: http://www.nytimes.com/2004/09/21/business/21grass.html
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