Billions at risk from wheat super-blight

An infection is coming, and almost no one has heard about it. This infection isn't going to give you flu, or TB. In fact, it isn't interested in you at all. It is after the wheat plants that feed more people than any other single food source on the planet. And because of cutbacks in international research, we aren't prepared. The famines that were banished by the advent of disease-resistant crops in the Green Revolution of the 1960s could return, Borlaug told New Scientist.

The disease is Ug99, a virulent strain of black stem rust fungus (Puccinia graminis), discovered in Uganda in 1999. Since the Green Revolution, farmers everywhere have grown wheat varieties that resist stem rust, but Ug99 has evolved to take advantage of those varieties, and almost no wheat crops anywhere are resistant to it....

....What's more, Ug99 will find agriculture has changed to its liking in the decades stem rust has been away. "Forty years ago most wheat wasn't irrigated and heavily fertilised," says Borlaug. Now, thanks to the Green Revolution he helped bring about, it is. That means modern wheat fields are a damper, denser thicket of stems, where dew can linger till noon - just right for fungus.

Another worry is that travel has exploded in the past 40 years. There have now been several documented cases of travellers carrying rust spores on their clothing. Some fear Ug99 will hitchhike as much as it flies - and its spread need not be innocent. New Scientist has learned that the US Department of Homeland Security met in March to discuss the possibility that someone could transport Ug99 deliberately.