Researchers forecast possible annual losses of up to 10 million tonnes, enough to feed 140 million people.

The picture is not the same everywhere. Changes to regional rainfall patterns mean there will be big winners and losers, while some countries will not see any difference or may even enjoy a benefit.

In Latin America, large corn-producing countries such as Brazil and Mexico will be badly hit, while Chile and Ecuador will be relatively spared.

In Africa, yields will catastrophically affected in South Africa, Tanzania and Zimbabwe, whereas in the western countries of Nigeria, Ivory Coast and Morocco, the harvest will be stable or slightly better than today.

The authors are Peter Jones of International Centre for Tropical Agriculture (ICAT) in Cali, Colombia and Philip Thornton of the International Livestock Research Institute (ILRI) in Nairobi, Kenya.

Corn, also known as maize, is the third most important crop in the world, after rice and wheat.

About half is grown in developing countries and is a staple for many poor families.

The study calls for greater effort into breeding drought-tolerant crops to help meet the looming crisis.

SPACE.WIRE