Beware of tests for roundup ready corn


AMES, Iowa – Iowa State University is advising grain farmers and elevator operators to be cautious of new testing kits for rapid detection of Roundup Ready corn.

Monsanto’s Roundup Ready corn has been genetically modified to tolerate Roundup herbicide. The European Union is not accepting corn or corn products containing the Roundup Ready trait.

Two Roundup Ready corn modifications are in use. One is called the GA21 event and the other the NK603 event.

“The overwhelming majority of Roundup Ready corn planted this year contains the GA21 event, which is still unable to be quickly detected by any testing kit,” said Charlie Hurburgh, professor in charge of the Iowa Grain Quality Initiative at Iowa State University.

New testing kits detect the NK603 event, which will be more widely planted in the future, Hurburgh said.

The importance. “This is important because it means there’s still no other means to isolate Roundup Ready corn other than farmers’ voluntary efforts to separate the corn from non-GMO varieties.

“Farmers who planted Roundup Ready corn signed a voluntary agreement with Monsanto to divert the corn away from markets serving the European Union.”

Because the corn wet-milling industry provides gluten feed and meal to Europe, keeping Roundup Ready corn separate is important to a major share of Iowa and Midwestern corn markets, Hurburgh added.

Do your homework. Before marketing their new Roundup Ready corn crop, Hurburgh advised corn growers to verify whether potential market outlets are still accepting Roundup Ready corn, and to notify them in advance of their intentions to market the grain.

Although no quick test is yet available, a more exhaustive polymerase chain reaction test is able to detect the presence of the Roundup Ready gene.

“But such testing is more likely to be done by the receiver of the grain or grain products, at which point management of problems is both costly and difficult,” Hurburgh said.

“Because of the voluntary agreement and other public information on the status of biotech products, producers could become involved in the chain of responsibility if required notification and segregated marketing practices aren’t followed,” he said.

For more information, farmers can check the Iowa Grain Quality Initiative Web site,


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