Sounding the Alarm: more wheat rusts incoming

John Bakum
Friday, February 3, 2017

The first week of February saw notices and alarms sounding for new wheat rust races that are threatening vital wheat growing areas. This crucial information is is available due to the collaboration among many scientists and institutions from all over the world including surveillance workers, phenotyping and genotyping laboratories, meteorlogical scientists all willing to share resources and data. Such collaboration is key to efforts to eradicate wheat diseases and the BGRI salutes everyone involved.

With new funding arriving in the form of UK aid investment from the British people, the Delivering Genetic Gain in Wheat project aims to continue fighting these diseases of wheat, especially in the Surveillance objective, led by Dr. Dave Hodson, CIMMYT.

The first alarm is regarding stem rust race TTTTF, which was discovered in Sicily in 2016. From Rusttracker:

Results of extensive lab tests of samples of stem rust have shown that the 2016 stem rust epidemics in Sicily were caused by a new, highly virulent variant of race TTTTF. The samples were collected during serious and unusual outbreaks of wheat stem rust on both durum wheat and bread wheat in Sicily during April – June 2016.
The epidemics were estimated to cover several thousands of hectares resulting in high inoculum load that could pose a threat to surrounding wheat areas in the forthcoming 2017 crop season, if environmental conditions prove suitable. Growers in at risk areas should be aware of the possible risk (on both durum and bread wheat), monitor crops for the early appearance of stem rust and undertake timely control if necessary.

For more information, please consult CIMMYT's RustTracker website

Second is two new races of yellow rust that caused epidemics in Europe, East Africa and Central Asia in 2016. From the Global Rust Reference Centre:

Two important new races having unique molecular genotypes were detected across wide areas in Europe/North Africa and East Africa/Central Asia, respectively. One of the races, temporarily designated “Pst(new)” was detected in Morocco, Italy and northern Europe, where sampling was done systematically in 2016. The race was most prevalent in Morocco, a non-epidemic situation during the drought in winter and spring in that area, and on Sicily in a severe epidemic situation, where yellow rust until recent years was considered insignificant.

For more information please consult the Global Rust Reference Centre

Helping bring this news to the world is a news bulletin from FAO: Spread of damaging wheat rust continues: new races found in Europe, Africa, Central Asia and an article in Nature also highlights the issues.

For more information about stem rust race TTTTF, please visit the Pathogen section of this website for race nomenclature, virulence patterns for TTTTF and other stem rusts including the Digalu Race (TKTTF) and Ug99 (TTKSK) and its varients.