Scientists searching for ways to combat the spread of Ug99, a deadly stem rust disease that infects wheat, are making progress against the dreaded fungus. Ug99 was first discovered in Uganda in 1999 and researchers say it can destroy up to 80 percent of the world’s wheat varieties.

Although Ug99 has not made it to the United States, researchers here fear it will eventually reach North America’s shores. Research into developing resistant varieties has primarily been conducted in Africa, where the disease was first discovered.

Brian Steffenson, crop scientist at the University of Minnesota, along with others around the world has created thousands of experimental new hybrids that are being tested in the Rift Valley. According to an article from, one new variety was derived from a Brazilian wheat strain. “It has shown promise, but it's still too risky to stop using chemical fungicides. New hybrids that continue to pass muster must be sent ‘seed multiplication’ and enter the chain of commercial production and retail distribution,” Bruce Nightingale, who owns a large family farm operation in Kenya’s Rift Valley, told

One Kenyan scientist anticipates that new resistant varieties won’t be available commercially until 2016. In the meantime, the spread of Ug99 has many wheat farmers worried. Ug99 spores have been reportedly found in Yemen and as far east as Iran. If it reaches Pakistan, India and China, serious implications for worldwide wheat production could reach a critical point.

Read the full PBS article here.