The world's leading crop scientists have warned that a deadly airborne fungus could devastate wheat harvests and lead to famines and civil unrest over significant regions of central Asia and Africa.
Ug99 – so called because it was first seen in Uganda in 1999 – is a new variety of an old crop disease called "stem rust", which spread from Africa to Iran and has blighted wheat production in many parts of the world for thousands of years. The fungus was thought to have largely disappeared since the 1960s when disease-resistant varieties were developed and widely planted in both the west and in developing countries.
Scientists meeting in Mexico to exchange information on Ug99 are alarmed because the new disease specifically targets resistance genes in wheat. As a result, it is now believed that 80-90% of all wheat varieties grown in developing countries are susceptible to the fungus.
Ug99 is particularly dangerous because it can infect crops very quickly and releases vast clouds of invisible spores which can be carried by the wind for hundreds of miles.