WIREDGOV

New research reveals for the first time the most likely months and routes for the spread of new strains of airborne ‘wheat stem rust’ that may endanger global food security by ravaging wheat production across Africa, the Middle East, Asia and the wider world.

Stem rust, named for the blackening pustules that infect plant stems, caused devastating crop epidemics and famine for centuries before being tamed by fungicides and resistance genes.

Since the turn of the century, however, aggressive new strains have emerged – such as ‘Ug99’, first detected in Uganda in 1999 – that infect widely grown varieties of wheat. These diseases threaten to disperse trillions of pathogenic fungal spores on winds across countries and continents. The current global economic loss from wheat stem rust is approximately U.S. $1 billion a year.

The fear is that these airborne and highly virulent strains could spread from known sites to some of the world’s most important ‘breadbasket’ regions, such as the Punjab in South Asia, where these strains have not yet been detected.

Now, a team of scientists of the University of Cambridge, the UK Met Office and CIMMYT (International Maize and Wheat Improvement Centre) have adapted modelling systems previously used to forecast, ash dispersal from erupting volcanoes and radiation from nuclear accidents (NAME), to predict when and how Ug99 and other such strains are most likely to spread.

The research, published yesterday in the journal Nature Plants, quantifies the circumstances – routes, timings and outbreak sizes – under which dangerous strains of stem rust pose a threat from long-distance dispersal out of East Africa to the large wheat-producing areas in India and Pakistan.

Click here for full press release