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ANOTHER SOURCE OF UNEASE is that there is a large blind spot when it comes to gathering intelligence about stem rust. After the severe U.S. rust epidemics of the 1950s, 'trap plots' were monitored across Africa to provide advance warning of stem rust. But as Jesse Dubin, a former associate director of CIMMYT pointed out, in the 1980s the funding to maintain them was cut.
Now the United Nations Food and Agriculture Organisation (FAO) is taking charge of rebuilding that surveillance, but monitoring millions of hectares of wheat fields across remote regions of Asia and Africa for rusty pustules on wheat stems is no easy task.
That's Keith Cressman's responsibility: his job is somewhat easier because he already runs the FAO's trans-boundary locust forecasting service. This involved training local people to monitor and report locust sightings – if there are locusts in Somalia, the FAO will warn the neighbouring Ethiopians. Some of these trainees will now also monitor stem rust.
But reporting stem rust takes much more skill than reporting locusts. It's not enough to train someone to detect rusty pustules on wheat stems, and equip them with a portable GPS and a mobile phone. Not all stem rusts are equal: some might be the plant's equivalent of an annoying cold; others have killer flu potential.
The rust detective would have to try and sort this out using a panel of 'canary' wheats: for instance wheats that carry the Sr31 gene. If the rust grows on Sr31 wheat, that's likely to be the killer variety.
Sounds simple, but it's not. As Rick Ward, project coordinator for the Durable Rust Resistance in Wheat at Cornell University told me, "reading the pustules is an art form". And false alarms can have devastating consequences for global food prices and availability. With jittery futures markets paying close attention to Ug99, there is the potential to send grain prices soaring, causing the catastrophic hoarding of grain.
The diagnosis of a brewing Ug99 epidemic requires the skills of an expert plant pathology lab. And there are precious few of them: India and South Africa have them, but won't accept foreign samples of stem rust. Neither will Australia's elite lab at the University of Sydney's Plant Breeding Institute in Cobbitty, New South Wales.
The only two places where the rust detectives can send their suspects is to the USA's Cereal Disease Laboratory at the University of Minnesota, in Saint Paul, or to Canada's Cereal Research Centre at Winnipeg. "That's pretty darn thin for a planet," says Ward.
These countries are so frightened of Ug99, the labs will only test the spores in the heart of winter when there is little chance they can escape the lab. So if a virulent new strain of Ug99 is brewing in Pakistan right now, researchers won't know for sure until the northern winter – which could be a whole year later.
The worst case scenario is that breeders may have already lost the arms race without knowing it: UG99 could have mutated to a form that will overwhelm the defences of seeds being multiplied. Ug99 is particularly shifty: it has already mutated once since it was detected in 1999: Kenya has a variety that resists both Sr31 and another key resistance gene, Sr24. The rust monster may be way ahead of the breeders.
"We're in a very dynamic phase. All of a sudden the pathogen adapted – we don't where it will end," says Cobus Le Roux, a researcher at South Africa's Small Grain Institute.
Only careful intelligence gathering can help the breeders stay ahead. "There's unquestionably a problem with analysing rust [strains]," says Robert Park, director of rust research at the University of Sydney's Plant Breeding Institute and leader of Tracking and Surveillance within the Durable Rust Resistance in Wheat – a project with the Borlaug Global Rust Initiative that is funded by the Gates foundation. One of Park's jobs is to help establish expert laboratories in the regions at risk – a goal that is about two years away.
Problem is, stem rust spreads like wildfire. If weather conditions are right (moisture and warmth) and if there is plenty of fuel (susceptible wheat), then the epidemic can rage out of control. "It's a roll of the dice," says Lumpkin.
Black Harvest Report
Congratulations to Elizabeth Finkel for this report. I just StumbledUpon the article and it is the most interesting article that I have read in years.
Well Done.
George
Scary - and what about the economics of it all?
I would love to hear more about this scary issue, especially about the economic aspects. At first sight it sounds like only the big companies like Monsanto will be able to produce resistant wheats continually. They will probably patent all that - won't they? Isn't it ironic that our stock market driven greed in the north will not be able to protect us from possible starvation, but just helps the rust to grow stronger in the South and spread from there? Isn't it time that all this information becomes open source? Should we really keep on allowing patents on plants, genes etc?
Goetz
Public vs Private sector wheat improvement
Turns out that other than Western Europe and Australia, world wheat improvement (breeding, pathology, seed systems, etc.) is primarily in the hands of the public sector. Catalyzing synergies and focus within and among the enormous array of public sector science and technology capacities in wheat is largely what the Borlaug Global Rust Initiative is about. But Goetz is right to flag the risk of restrictions on use of valuable genetic resources, as IP encumbrances are as likely to emerge from the public sector as they are from the private.
Rick Ward, BGRI/Cornell
Excellent article
Great job Elizabeth Finkel, this was a great read. Until today I did not know Norman Borlaug played such a key role in solving the rust problems several decades ago. We can only hope someone is willing to put in the effort to carry on his work, whether its public or private. With current global grain reserves being so low, farmers holding off on using potash fertilizer because of high prices and less than ideal growing conditions this year for north american crops those reserves are shrinking rapidly on their own. I don't think the world can handle another grain shock due to wheat rust in the next 2 years. A grain crisis could be the next black swan.
sr31
This is a fantastic article which I thoroughly enjoyed reading. In lectures I prepared for my students last year, I concluded Ug99 is probably not a major threat to Australia, in the sense that sr31 and sr24 arn't widely used genes in our common varieties here. Lets hope so anyway.
Karen Barry, UTAS, Lecturer (Plant Pathology)
Park (2007) Stem rust of wheat in Australia. Australian Journal of Agricultural Research, 58: 558-566.