Byline: David R. Sands, THE WASHINGTON TIMES

A lethal variant on an ancient disease affecting wheat has spread from its base in Africa to Iran and now threatens vast fields in South Asia, the Middle East and Europe at a time of global food shortages, agricultural specialists warn.

The new strain of wheat-stem rust, first identified in Uganda nine years ago, is threatening crops during a global crisis over rising food prices, depleted reserves, rising agricultural trade barriers and violent food-related protests on four continents.

The U.N. Food and Agriculture Organization (FAO) reported in early March that the new wheat fungus had been found in fields in western ...