ST LOUISMonsanto Company today said tests it conducted indicate a genetically-modified (GMO) version of wheat that was recently detected on an Oregon farm is not pervasive in the Pacific Northwest.

After testing varieties of wheat that were available to farmers throughout Oregon and Washington, Monsanto did not detect the GMO crop in any of the samples, Robb Fraley, Monsanto's chief technology officer, told reporters Wednesday. The tests represent about 60% of all acres of soft white winter wheat seed grown in 2011, he said.

Monsanto and the U.S. Department of Agriculture (USDA) are investigating how the genetically-modified wheat ended up on an Oregon farm. Fraley said the discovery could have stemmed from an intentional or accidental act. Through testing, an Oregon State University scientist and USDA discovered the crop matched Monsanto's wheat.

USDA has not authorized the commercial production of the crop, which is resistant to glyphosate, a popular herbicide. U.S. farmers widely plant other glyphosate-resistant crops that Monsanto has engineered, including "Roundup Ready" corn and soybean.

USDA's Animal and Plant Health Inspection Service (APHIS) has said the Roundup Ready wheat does not present a food-safety concern.

Monsanto was authorized to test its Roundup Ready wheat for several years. APHIS said it authorized more than 100 field tests during the years from 1998 through 2005.

Monsanto discontinued its program in 2005 following trials in 16 states, including Oregon.

When the program was closed down, the cooperatives with which Monsanto was conducting the research either destroyed the samples or shipped them to a USDA storage facility in Colorado, Claire CaJacob, the senior lead of Monsanto's wheat technology platform, told reporters Wednesday.

"The process for closing out the Roundup Ready wheat program was rigorous, well-documented and audited," the company states online in a media presentation.

Monsanto also has confirmed that no Roundup Ready wheat tests were conducted in Oregon over the last decade.

Still, the company isn't ruling out any scenario that would explain the detection of its Roundup Ready wheat, such as the possibility that its seeds were intentionally taken out of a field and planted. Neither USDA nor Monsanto have implied the Oregon farmer is guilty of any wrongdoing.

The wheat discovery was brought to the attention of APHIS by an Oregon State University (OSU) scientist who sampled the crop after the farmer detected glyphosate-resistant wheat that had not been intentionally planted.

Should a wrongdoer in APHIS' investigation be found to have violated the federal Plant Protection Act, it could face civil penalties of up to $1 million and criminal prosecution, the agency said.

Monsanto believes the genetically-modified trait was only detected in a small percentage of plants in one field, although Fraley acknowledged Monsanto doesn't have first-hand knowledge. The company said it has requested the samples from USDA and the OSU scientist. Monsanto also has been in touch with the farmer's lawyer.

However, an OSU weed-science professor involved in the initial investigation, Carol Mallory-Smith, told The Wall Street Journal that she offered a sample to Monsanto in early May but the company declined.

Phil Miller, Monsantos global regulatory affairs lead, acknowledged USDA has responsibility to conduct a probe and that there are limitations on what the agency will share.

The wheat discovery has led to some countries, including Japan and South Korea, suspending certain imports of the crop. Monsanto has provided a testing methodology to identify the GMO seed to several foreign governmentsincluding Japan, Korea, Taiwan and the European Unionat their request, Fraley said.

The revelations have created an obvious distraction, diversion of resources and potential liability for Monsanto, which already faces at least one lawsuit.

A Kansas farmer claims the company's negligence has resulted in declining wheat prices and closed doors to countries that import U.S. wheat. Monsanto has denied any liability and promised to mount "a vigorous defense."