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Scientists Join In Battle To Head Off Ug99

Amutant form of stem rust that wipes out wheat crops could spread to top producers in Asia unless new resistant varieties of wheat are distributed widely, experts say.

Stem rust “annihilates, that’s not an exaggeration,” said Rick Ward, a rust expert from Cornell University.

“Basically the entire world’s wheat crop is fertile breeding ground,” Ward told Reuters ahead of a global meeting on the blight in Mexico last week.

The fungus has plagued wheat since biblical times, causing crop failure and famines. It was largely controlled in the 1950s as scientists passed out seeds with a gene to block the disease, a reddish dust that attacks the plant’s stalks.

But a deadly new strain of the rust discovered in Africa in the late 1990s poses a serious threat to 80 per cent of the world’s wheat supply, according to the United Nations.

Some of the 300 international experts at the event called for a co-ordinated push to replace the bulk of the world’s commercial wheat with new seeds bred to fight the fungus.

The effort, while costly, would be more affordable than mass spraying of expensive and potentially harmful fungicides, said Ravi Singh, a scient ist at the International Maize and Wheat Improvement Center in Mexico, or CIMMYT, hosting the conference.


The mutant rust is known as Ug99 because it first emerged in Uganda in 1999 and spread from there to Kenya and Ethiopia.

The wind then carried it to Yemen and last year it was discovered in Iran, some 2,700 miles (4,400 kms) from Uganda.

Researchers fear it will jump to India, the world’s No. 2 wheat producer after China. If weather conditions are right stem rust can devastate up to 70 per cent of an affected crop.

“If that rust goes from Iran to India it doesn’t have to take out too much before the markets just get spooked,” Thomas Lumpkin, the director of CIMMYT said.

“If it hits the No. 2 wheat producer traders will go wild. You see what happened last year, and it could be far worse than that,” Lumpkin said.

Food prices spiked last year as grain crops were diverted to make biofuels sparking food riots around the globe.

Hopes of slowing the spread of Ug99 hinge upon new wheat varieties bred with genes designed to protect against the rust. CIMMYT and researchers around the world are testing thousands of these new breeds at a giant nursery in Kenya, where Ug99 has been present since 2001.

Some 60 resistant seed strains have been discovered, and they also produce more wheat per hectare, Singh said.

Governments need to distribute the new seeds and fund more research to fight the rust, said an opinion article in the New York Times by Nobel Peace Prize-winning scientist Norman Borlaug, credited with launching the Green Revolution and fighting rust in the 1950s.

The Bill and Melinda Gates foundation has pledged $27 million to combat stem rust, which also attacks barley, and U. S. President Barack Obama has asked the U. S. Congress to approve $1.1 billion for agricultural science.

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