Half of Malawi's maize has been infected by crop-munching armyworms, a senior government official said on Thursday. The pest has infested 35,870 hectares, or 50.3 percent, of the planted irrigation maize by October, Albert Changaya, an official in Malawi's agricultural department told a U.N. Food and Agriculture Organisation meeting in Johannesburg. "Last month the report that we got was about 50 percent...," said Changaya, who is responsible for technical services and agricultural expansion in the department. Despite damage inflicted by armyworm, Malawi produced a bumper 2017 crop of around 3.2 million tonnes, paving the way for government to lift a two-year maize export ban.