Contact: Tim Murray, WSU Department of Plant Pathology, CAHNRS, 509-335-7515, tim_murray@wsu.edu
WSU Professor to Lead Recovery Efforts Against Invader
PULLMAN, Wash.-A fungus that could damage U.S. wheat and barley crops is on its way from Africa, and a Washington State University professor will chair a national committee to prepare the recovery plan.
Since its discovery several years ago, this race, or variety, of stem rust fungus - Ug99 - has been travelling from Uganda to Kenya to Yemen and was most recently found in Iran.
Tim Murray, professor of plant pathology at WSU and an expert on wheat diseases, will lead a national, multiagency effort to prepare a recovery plan should Ug99 be introduced to the United States. In addition, he will participate in an international conference in March to address the threat.
"The fungus travels with the wind and will eventually spread into Central and South East Asia and Europe," said Murray. "If, or when, it arrives in the U.S. could be due to human activities, intentional or unintentional, or also by wind currents." It could take up to ten years for this race of stem rust fungus to arrive in the U.S. if it follows natural pathways.
The Ug99 is a genetic variation of the black stem rust, an ancient disease that is even named in the Bible. The fungus becomes specialized to infect different varieties of crops. Specifically, wheat and barley will be the crops at risk if Ug99 enters the U.S.
Crop varieties in the nation lack the gene that could resist the disease and Murray said it could take 10 or 12 years to develop a variety resistant to Ug99. "There are registered fungicides for effective control, but usually natural genetic resistance has worked very well," he said.
"When a plant is infected, the fungus enters the plant through its natural openings, grows in leaf tissue, produces rusty brown colored spores -hence its name-and the spores erupt through the surface of the plant, interfering with the flow of water of the plant. The result is reduced grain production. Add the cost of products such as fungicide to that and you can see how there will be a problem with a reduced production and higher costs."
Because stem rust is already a well-established crop disease in the U.S., "the challenge with Ug99 is to know when it appears and to be able to identify it, since it looks exactly as any other stem rust strain. Enhancing existing surveillance activities to improve our ability to detect Ug99 is critical. Trap plots with different varieties will be perfect indicators of when and where Ug99 appears," Murray said.
"The invitation to lead this national effort is a recognition of Dr. Murray's expertise in this area and WSU's role as a pre-eminent institution in research on various aspects of wheat," said Hanu Pappu, chair of the Plant Pathology Department.
Murray was also invited to participate in an international conference focused on Ug99. The conference is being organized by Norman Borlaug, who won the Nobel Peace Prize in 1970 for contributions to the Green Revolution. He has continued as an advocate for agriculture in the developing world.
The Borlaug Global Rust Initiative was established by several international agricultural research centers in response to Ug99. Its overarching objectives are reducing the world's vulnerability to rust diseases of wheat; advocating for a sustainable international system to contain the threat of wheat rusts; and withstanding future global threats to wheat.
"This conference brings together the world's experts on wheat rusts to discuss all aspects of the current state of knowledge of Ug99," Murray said. "We will talk about disease movement, progress on breeding lines, chemical control and surveillance and tools for identification."
Xianming Chen, research geneticist with USDA-ARS and an adjunct professor in plant pathology, also will represent WSU at the conference.