Zambia, Lesotho, Malawi, Ethiopia, Mozambique, and Zimbabwe — not exactly marvels of good nutrition — have been destroying food shipments from America. Why? This will sound like a sick joke, but they are afraid of genetically-modified foods. These countries have now expressed official opposition to American food entering their country, at a time when almost 3 million Zambians, to cite just one example, desperately need food aid.
There is another villain in the story, namely some of the European nations. The Africans fear that if they accept genetically-modified foods, the seeds will mix with their current crops. Europe will then be reluctant to import African foodstuffs. By the way, Greenpeace opposes the food shipments as well.
Peter Pringle offers a good survey of the debates on genetically-modified foodstuffs.