The main opposition candidate in Nigeria's April presidential elections works in an environment of arcadian plenty that belies his reputation for harsh asceticism. Muhammadu Buhari, a former military dictator famous for launching an authoritarian "war on indiscipline", uses a government-owned office whose lush gardens yield mangos, guavas and pawpaws. The view of the building from the road is dominated by a strikingly expansive tree from whose branches brown pods hang like socks on a washing line.