Red Menace: Stop the Ug99 Fungus Before Its Spores Bring Starvation | Magazine

Stem rust is the polio of agriculture, a plague that was brought under control nearly half a century ago as part of the celebrated Green Revolution. After years of trial and error, scientists managed to breed wheat that contained genes capable of repelling the assaults of Puccinia graminis, the formal name of the fungus.

But now it’s clear: The triumph didn’t last. While languishing in the Ugandan highlands, a small population of P. graminis evolved the means to overcome mankind’s most ingenious genetic defenses. This distinct new race of P. graminis, dubbed Ug99 after its country of origin (Uganda) and year of christening (1999), is storming east, working its way through Africa and the Middle East and threatening India and China. More than a billion lives are at stake. “It’s an absolute game-changer,” says Brian Steffenson, a cereal-disease expert at the University of Minnesota who travels to Njoro regularly to observe the enemy in the wild. “The pathogen takes out pretty much everything we have.”