Our Mission
For Pharma
Edible Vaccine
USDA rules
List of Growers
Other Medical
Non Medical
Farm Bureau
Latest News
Cleaning Waste
E.U. Directive

How can Environmental Safety in Molecular Crops be achieved ? - What we want to see happening.

CSU study on bio-corn buffer zones
By Jim Erickson, Rocky Mountain News © Denver Publishing Company
July 15, 2003

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.

© 2002 -

Recombinant Proteins from Plants: Methods & Protocols - 2008. editors Loic Faye & Véronique Gomord