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2-Plants: New U.S. study on GE maize buffer zone concept

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                                  PART I
-------------------------------- GENET-news -------------------------------

TITLE:  CSU study pops theory on bio-corn buffer zones
SOURCE: Rocky Mountain News, USA, by Jim Erickson
DATE:   Jul 15, 2003

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CSU study pops theory on bio-corn buffer zones

Colorado State University researchers say wind-blown corn pollen can
pollinate corn plants up to 600 feet away, raising questions about the
size of the buffer zones needed to isolate genetically modified crops.

In February, Boulder County commissioners voted to allow farmers to grow
genetically modified corn on county open space.

But commissioners said that neighboring growers of conventional crops
could demand a 150-foot buffer zone around the genetically modified varieties.

Results of a 2002 CSU pollen study, released Monday, show that more than
99 percent of the pollen from corn plants travels 150 feet or less. But
at test plots in Boulder County, a tiny amount traveled 600 feet and
cross-pollinated corn plants there.

"At 600 feet, we found one kernel that was cross-pollinated. If you
really want zero (cross-pollination), you would have to go maybe a mile
away," said Patrick Byrne, an associate professor of soil and crop
sciences at CSU.

Byrne served on a committee that advised Boulder County commissioners on
the issue of buffer zones around fields of genetically modified
organisms, or GMOs.

The 10-member advisory committee was apprised of the CSU findings but
decided that a 150-foot buffer was adequate, said organic farmer John
Ellis, who served on the committee.

"I don't support GMOs, but the likelihood of it doing any damage beyond
100 feet was pretty low, as far as cross-pollination," said Ellis, who
has a 6-acre organic peach orchard in Palisade.

"My gut feeling was that it wasn't right, but it was better than
nothing," he said. "One hundred fifty feet was probably as much as we
were going to get the commissioners to agree on."

About 40 percent of the corn grown in the United States has been
genetically altered to include a gene from another organism. One common
variety, Roundup Ready corn, contains a gene that makes corn resistant to
the widely used Monsanto weed killer Roundup.

About 1 million acres of corn were planted in Colorado this year, mostly
in the eastern part of the state. The percentage of Colorado corn that is
genetically altered is a bit less than the national average,

Byrne said.

In June, the state approved a French company's request to grow 30 acres
of corn genetically altered to produce a protein that would be used to
treat digestive disorders. But the company later decided not to pursue
the Colorado "bio-pharming" project in 2003.

In the CSU study, researchers used test plots of blue-kernel corn in
Boulder County and Roundup Ready corn in Morgan County, in northeast Colorado.

In Boulder County, 2 acres of blue-kernel corn were surrounded by large
fields of conventional yellow corn. When pollen from the blue-kernel corn
pollinated plants outside the 2-acre test plot, some of the kernels in
the new-grown ears turned blue.

In a Morgan County test, 160 acres of Roundup Ready corn were grown
alongside 160 acres of conventional corn. Ears from the conventional corn
were harvested, and the kernels were exposed to a Roundup solution.

The young plants that survived had received pollen from the Roundup Ready
corn, which made them resistant to the weed killer.

A second round of testing is under way now in Boulder and Weld counties.

                                  PART II
-------------------------------- GENET-news -------------------------------

SOURCE: Colorado State University, News Release
DATE:   Jul 14, 2003

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FORT COLLINS - A Colorado State University study takes a step towards
finding solutions to pollen drift from genetically modified plants onto
organic and traditionally grown crops, a concern raised by some members
of the public. The study shows that in Colorado, about 150 feet may be a
reasonable buffer zone between genetically modified corn plots and
organic and traditional corn plots to prevent significant cross-
pollination due to pollen drifting from one field to another.

The first round study was conducted in Morgan County in eastern Colorado,
the state's corn belt - and also a windy area in the region, and at a
second location on a plot in Boulder County. Results showed that less
than 1 percent of corn farther than 150 feet from test plots is cross-
pollinated by pollen from the test corn. That means that very little of
the pollen from the test corn fields drifted more than 150 feet.

"We realize that one year's data is not sufficient for this type of
study," said Patrick Byrne, Colorado State University crop sciences
professor and researcher. "Given the year-to-year variability in weather
conditions, we will repeat the research again during the 2003 growing season."

The study tracked drift of blue kernel corn pollen at one site in Boulder
County and the drift of Roundup Ready corn, a genetically modified crop,
at the Morgan County site. The corn was planted adjacent to corn
varieties without those traits. When the corn was harvested, samples were
collected from various distances away from the test plots. These samples
were tested for traits from the test plots, which indicate the amount of
cross-pollination. The farthest sample was collected 305 meters - about
915 feet -- away from the edge of the test plots.

Cross-pollination was highest at the closest sampling sites -- up to 46
percent at three-quarters of a meter south of the blue corn plot in
Boulder County. However, cross-pollination dropped off in a short
distance, with only 0.5 percent cross-pollinated kernels near the blue
corn plot at 150 feet. At that same distance in the Morgan County plot,
0.75 percent of the corn showed cross-pollination with the Roundup Ready
test plot. The farthest distance at which any cross-pollination was
detected was 600 feet in Boulder County and 270 feet in Morgan County.

"The growth in U.S. acreage planted with genetically modified crops has
been paralleled by growth in the demand for organically produced foods,"
said Byrne. "It can be argued that both genetically modified and organic
agriculture are approaches to improving conventional farming methods, but
the two forms of agriculture are in conflict because of U.S. organic
standards that prohibit the use of genetically modified products and
pollen drift from genetically modified crops to nearby organic fields.
Given the growing importance of both the biotechnology and organic
sectors of food production, co-existence between the two becomes a
critical issue. We hope that this study will eventually help to establish
protocols for co-existence of these two types of food production."

This study came out of discussions in Boulder County, where Byrne served
on a committee to study the concerns of that county's residents,
particularly those who raise organic crops, with allowing the farming of
genetically modified crops on county-owned open space land. The study was
used to establish genetically modified crop protocols on county open
space cropland.


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