“A global food crisis is a distinct possibility” if scientists are unable to develop wheat varieties resistant to a deadly fungus leapfrogging through wheat fields overseas, says Norman Borlaug, the Nobel Prize-winning agronomist and Green Revolution researcher. Today's mutant form of stem rust, known as Ug99, could spark an agricultural disaster, say international wheat experts who convened recently to combat it.

How would Ug99's spread affect American corn and soybean growers? “Two things would occur in the event of a large Ug99 outbreak,” predicts Agricultural Economist Bruce Babcock, director of the Center for Agriculture and Rural Development. “Because the developed world has the capital to fight rust with scouting and fungicides, any domestic acreage shifts would probably be less than what we might expect,” Babcock says.

“Soybeans would be the most suitable replacement crop for wheat, given that many current wheat and barley varieties are susceptible to this particular race of the stem rust pathogen. A shift of soybeans into wheat belts would in turn lower soybean prices. The drop in soybean prices would increase corn acreage.

“Another reaction would be skyrocketing wheat prices,” Babcock adds. “But because wheat is a feed-grain, a global shortage would increase corn prices.”

Ug99 is virulent to over 80% of all wheat varieties grown globally. It first emerged in Uganda in 1999 — hence Ug99 — and has since spread east and northeast through Africa, and into southwest Asia, as far north as Iran. Wind models indicate the disease may next spread into Pakistan, Afghanistan and India. The reddish, wind-borne fungus Ug99 has destroyed 80% of the wheat in farmers' fields in parts of Kenya.