Washington State University researchers this month completed testing of all of the university's wheat varieties, as well as other Northwestern varieties, finding no GM resistance similar to that exhibited by plants discovered in May in an Oregon field.

WSU researchers complete testing of Northwest wheat varieties following Oregon identification of GM wheat.

WSU’s tests involved wheat varieties developed at the university, at sister universities and by two of the three largest commercial wheat seed companies in the Pacific Northwest, the University said. Among them were nearly 50 commercially grown varieties from the University of Idaho and Oregon State University; WSU varieties including Otto, Puma, Sprinter, Glee, Diva and Dayn; and 24 varieties from Westbred/Monsanto and Limagrain Cereal Seeds.

The tests also included 1,900 advanced breeding lines from WSU programs and more than 20,000 individual plots.

WSU began its investigation to supplement testing by Monsanto and the USDA Animal and Plant Health Inspection service, both of which have also announced that wheat varieties tested so far have been negative for the Monsanto glyphosate-resistant gene first identified this spring.

"WSU undertook its own investigation as part of its commitment to serving Northwest farmers and the agricultural industry as a whole,” said James Moyer, director of WSU’s Agricultural Research Center.

Moyer called the collaboration and cooperation from Pacific Northwest universities and businesses "unprecedented," nothing that it "reflects the common interest and goal of determining whether the genetically modified wheat discovered in Oregon was an isolated case or if the industry had a larger problem.

"WSU’s data clearly suggests this was an isolated case," he said.

The tests involved growing seed, spraying young plants with glyphosate and conducting molecular testing if necessary. None of the plants showed resistance to the herbicide.

Moyer said although WSU is not conducting research on wheat with the same properties as the variety found in Oregon, any unusual or unauthorized plant quality in the supply chain warrants a thorough assessment by all participants to maintain the confidence of Washington trading partners and consumers.

Though key trading partner Japan had halted purchases of U.S. wheat on concerns that the supply could be tainted with GM plants, the country has since resumed tenders for new purchases of U.S. Western White and soft white wheat.

Catch up on the latest GM wheat developments:
USDA Continues GM Wheat Investigation as Japan Lifts Import Ban
U.S. Representative Wants Answers on GE Wheat
USDA GE Wheat Investigation Continues
Monsanto Not Ruling Out 'Purposeful' Release of GE Wheat
GE Wheat Investigation Will Take Time, USDA Says
USDA Identifies GE Glyphosate-Resistant Volunteer Wheat