Rust diseases - a threat to global food security

Chronic food shortages caused by cereal rusts have happened in the past – and today international agricultural agencies are on the alert again because of a new threat in Eastern Africa, a rust known as Ug99.

A virulent disease of wheat, Ug99 has the potential to wipe out a quarter of the world’s wheat crop.

Next week, some of Australia’s and the world’s foremost experts in the field of rust diseases will be in Sydney to attend a symposium on the topic – “Rust Diseases: Threats to Global Food Security in the Context of Climate Change.”

The symposium has been organised by the NSW Centre for Plant and Animal Biosecurity, an alliance between the NSW Department of Primary Industries and the University of Sydney.

High on the agenda is the threat to global food security from Ug99, which last month was reported to have jumped from eastern Africa and is now infecting wheat in Yemen in the Arabian Peninsula.

Countries in the predicted pathway of Ug99 grow more than 65 million hectares of wheat a year.

NSW Department of Primary Industries (DPI) Principal Research Scientist, Dr Colin Wellings said: “There is international concern that this new stem rust could destroy vast quantities of wheat and threaten food security at a time that world wheat stocks are at a historic low.

“The potential for the disease to move into Central Asia is enormous and alarming.”

Speakers at the symposium include the facilitator of the Global Rust Initiative (GRI), Dr Richard Ward, who is based at the international plant breeding centre CIMMYT in Mexico.

GRI was set up in 2005 in response to recurring epidemics of Ug99 in Kenya and Ethiopia. (In the early 1950s, a major stem rust epidemic in North America destroyed up to 40 per cent of that continent’s spring wheat crop.)

Dr Ward says that “the potential for a serious international epidemic of stem rust based on Ug99 has galvanized considerable global concern to secure wheat yield protection through breeding for rust resistance.”

In NSW, wheat growers are on alert because of the discovery of a new stripe rust which disarms a resistance gene that has been bred into some popular varieties of wheat.

Dr Wellings believes that growers have two to three years before the new stripe rust becomes problematic for wheat varieties carrying the Yr17 resistance gene.

“If this proves to be the case, then there should be time for farmers to change the varieties they are planting.”

Dr Wellings said that for nearly a century, DPI and University of Sydney scientists have been working to find new genes which confer resistance and breed them into Australian cereal varieties.

He said that in 1973 a stem rust outbreak caused “historic and massive losses” in crops in northern NSW and Queensland. This galvanised government and industry to take a national approach to work towards being prepared for new incursions.

The Cooperative Research Centre (CRC) for National Plant Biosecurity is a major sponsor of the symposium.

Speakers at the symposium include:

Mr Terry Enright, Chairman, Grains Research and Development Corporation
Prof John Lovett, Chairman, CRC for National Plant Biosecurity
Dr Sanjaya Rajaram, ICARDA-CIMMYT, Syria
Dr Les Szabo, US Department of Agriculture
Dr Rick Ward, Global Rust Initiative
Professor Robert Park and Dr Harbans Bariana, University of Sydney

The symposium is being held on 21 and 22 February at the Elizabeth Macarthur Agricultural Institute at Menangle, in Sydney’s south-west. The program is at:

Bookings are only open until midday Friday 16th February.