ANGE ABOA COCOA arrivals at ports in Ivory Coast fell this week because of a violent political standoff following a disputed presidential election in the world's top growing nation, exporters have said. The political crisis in the West African nation escalated this week after several opposition leaders who called for a boycott of the October 31 presidential election, rejected President Alassane Ouattara's victory and formed a parallel government. The government moved swiftly and placed them under effective house arrest, while a former rebel leader has called for the army to mutiny and join the opposition. Exporters said the cocoa sector,…