Ug99 Fungus: big ag problems ahead?

A neat follow-up to my eggplant post, with respect to how important the agricultural battles are going to be:

The enemy is Ug99, a fungus that causes stem rust, a calamitous disease of wheat. Its spores alight on a wheat leaf, then work their way into the flesh of the plant and hijack its metabolism, siphoning off nutrients that would otherwise fatten the grains. The pathogen makes its presence known to humans through crimson pustules on the plant’s stems and leaves. When those pustules burst, millions of spores flare out in search of fresh hosts. The ravaged plant then withers and dies, its grains shriveled into useless pebbles.

On the one hand, the rising population and their affluence will trigger higher demand for food of various types. On the other hand, the possibility of pests causing large-scale problems.  The report at Wired.com continues:

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.”

These are the kind of reports that make me dismiss the extraordinary events that Hollywood movies, for instance, portray as our huge dangers.  In contrast, it is such "small" and "old" problems that I worry will cause large-scale havoc on this planet.  It turns out that Yemen is at the nerve center of this problem too:

The fungus is also an efficient traveler: A single hectare of infected wheat releases upwards of 10 billion spores, any one of which can cause the epidemic to spread. The circumstances have to be just right, though — the prevailing winds must blow toward an area of wheat cultivation, and the P. graminis spores must survive the airborne journey.

That is precisely what happened in the case of Ug99. Two years after its initial discovery at Kalengyere, the pathogen drifted into the fields of central Kenya, where it caused major losses and wreaked havoc on thousands of subsistence farms. The pathogen’s next stop was Ethiopia, sub-Saharan Africa’s biggest wheat producer, followed by eastern Sudan. (So far, those two countries have escaped major damage thanks largely to dry weather, which tends to hinder.) By 2006, the pathogen had hopped over the Red Sea into Yemen, a disturbing migratory milestone. “I look at Yemen as the gateway into the Middle East, into Asia,” says David Hodson, former chief of Cimmyt’s Geographic Information Systems unit and now with the Food and Agriculture Organization in Rome, where he tracks global wheat rusts.