Lilongwe (Reuters) - Malawi expects its maize surplus to increase by nearly 50 percent this season, the minister of agriculture said on Tuesday, a rare economic bright spot for the impoverished southern African nation. Malawi expects a surplus of 740,000 metric tonnes, Peter Mwanza told Reuters, up from 500,000 metric tonnes in the previous season. Its national maize requirement is estimated at 2.8 million metric tonnes. A seed and fertiliser subsidy programme in recent years helped Malawi feed itself. ...