CHICAGO, Ill. (Reuters) — Syngenta has halted commercial sales in Canada of corn seed containing a new genetically modified trait because major importers have not approved the product, say two industry sources.

The variety contains the Agrisure Duracade trait that provides protection against rootworms.

The company will sell it in the United States, but growers there will be required to sign an agreement that requires them to feed the harvest to livestock or poultry on farm or deliver it to a company that doesn’t export it to China or the European Union.

The trait has been approved for cultivation in Canada, the U.S. and other countries and for import by some overseas buyers.

However, it has not been approved for import by China and the EU, which are major buyers.

The decision to pull the variety in Canada was announced in a Syngenta notice sent to Canadian seed dealers and obtained by Reuters.

In the U.S., Syngenta will advise farmers to harvest the variety separately, store it in separate bins and surround fields of Duracade corn with “buffer” rows of another variety, the newsletter said.

Top traders Archer Daniels Midland, Bunge and Cargill say they will limit their handling of Duracade corn because of the export problems.