Spread of damaging wheat continues in Europe, Africa, Central Asia
This is according to two new studies produced by scientists in collaboration with FAO.
The reports, highlighted in the journal Nature following their publication by Aarhus University and the International Maize and Wheat Improvement Center (CIMMYT), show the emergence of new races of both yellow rust and stem rust in various regions of the world in 2016.
At the same time, well-known existing rust races have spread to new countries, the studies confirm, underlining the need for early detection and action to limit major damage to wheat production, particularly in the Mediterranean basin.
Wheat is a source of food and livelihoods for over 1 billion people in developing countries. Northern and Eastern Africa, the Near East, and West, Central and South Asia – which are all vulnerable to rust diseases − alone account for some 37 percent of global wheat production.
Wheat rusts spread rapidly over long distances by wind. If not detected and treated on time, they can turn a healthy looking crop, only weeks away from harvest, into a tangle of yellow leaves, black stems and shriveled grains.
Fungicides can help to limit damage, but early detection and rapid action are crucial. So are integrated management strategies in the long run.
On the Italian island of Sicily, a new race of the stem rust pathogen −called TTTTF− hit several thousands of hectares of durum wheat in 2016, causing the largest stem rust outbreak that Europe has seen in decades. Experience with similar races suggests that bread wheat varieties may also be susceptible to the new race.
TTTTF is the most recently identified race of stem rust. Without proper control, researchers caution, it could soon spread over long distances along the Mediterranean basin and the Adriatic coast.
Various countries across Africa, Central Asia and Europe, meanwhile, have been battling new strains of yellow rust never before been seen in their fields. ■