Grain growers in Australia, the world’s third-largest canola exporter, may produce as much as 2 percent of this year’s harvest from genetically modified seed after bans on GM crops were lifted in two states. Farmers in New South Wales and Victoria may plant a total of 10,000 hectares to 12,000 hectares of Roundup Ready canola this year, or about 1 percent to 2 percent of the nation’s crop, Anna Hall, spokeswoman for Monsanto Co.’s Australian unit, said in a telephone interview from Melbourne.