Syngenta's corn, which has been engineered to protect against damage from insects such as corn borers and rootworms, was approved for use in the U.S. in 2010; Argentina and Brazil gave their blessing shortly afterwards. After almost four years of trying to persuade the Chinese to approve the trait, Syngenta finally won approval last December. During the lengthy approval process, while China's demand for corn soared from under 1 million metric tons a year to over 5 million tons, the Asian giant originally approved imports containing the corn trait. However, in 2013, China stopped taking corn and DDGs – rejecting entire shiploads and causing huge disruptions in the supply chain.