A new form of stem rust, a virulent wheat disease, has jumped from eastern Africa and is now infecting wheat in Yemen in the Arabian Peninsula.
Researchers with the Global Rust Initiative (GRI) and the Agricultural Research Service of the United States Department of Agriculture (USDA-ARS) have confirmed conclusively the existence of the disease in Yemen. There is also evidence that the disease has spread into Sudan but more tests are needed to confirm the finding. Until this discovery, this new strain of stem rust, known as Ug99, had only been seen in Uganda, Kenya and Ethiopia.
The last major epidemic of stem rust occurred in North America in the early 1950s, when a strain of stem rust destroyed as much as 40 percent of the continent's spring wheat crop. Out of this crisis came a new form of international cooperation among wheat scientists worldwide, spearheaded by Nobel laureate wheat scientist Norman Borlaug. This international alliance of scientists led to the development of wheat varieties which resisted the onslaught of stem rust for more than four decades. But in 1999, a new strain of stem rust was discovered in Uganda and Kenya capable of destroying most previously disease-resistant wheat varieties.
A year and a half ago geographic information systems specialists working at CIMMYT plotted the probable trajectory of the fungus, whose spores can travel large distances on the wind. The wind models predicted that if the fungus crossed from eastern Africa to the Arabian Peninsula it could easily spread to the vast wheat-growing areas of North Africa, the Middle East, Pakistan and India.
There is precedence for this, from a virulent strain of another wheat disease, called yellow rust, which emerged in eastern Africa in the late 1980s. Once it appeared in Yemen, it took just four years to reach wheat fields of South Asia. On its way, this new strain of yellow rust caused major wheat losses in Egypt, Syria, Turkey, Iran, Iraq, Afghanistan, and Pakistan, exceeding USD 1 billion in value. There is every reason to believe the new Ug99 strain of stem rust represents a much greater risk to world wheat production. Annual losses of as much as USD 3 billion in Africa, the Middle East and south Asia alone are possible.
According to the Food and Agriculture Organization of the United Nations (FAO), countries in the predicted, immediate pathway grow more than 65 million hectares of wheat, accounting for 25 percent of the global wheat harvest. "If we don't control this stem rust threat," says ME Tusneem, Chairman of Pakistan's Agriculture Research Council, "it will have a major impact on food security, especially since global wheat stocks are at a historic low."
Experiments conducted over the past two years by international researchers in the Global Rust Initiative in Kenya and Ethiopia demonstrate clearly that most of the world's wheat varieties are susceptible to the new Ug99 strain of stem rust. "This is a problem that goes far beyond wheat production in developing countries," warns Borlaug. "The rust pathogen needs no passport to cross national boundaries. Sooner or later Ug99 will be found throughout the world, including in North America, Europe, Australia and South America."
GRI scientists have already identified promising experimental wheat materials with resistance to Ug99. But from the first breeding trials to growing new, rust-resistant varieties in farmers' fields on millions of hectares takes time and a massive effort.
"If we fail to contain Ug99 it could bring calamity to tens of millions of farmers and hundreds of millions of consumers," says Nobel Laureate Borlaug. "We know what to do and how to do it. All we need are the financial resources, scientific cooperation and political will to contain this threat to world food security."
David Mowbray | EurekAlert!
Researchers discover natural product that could lead to new class of commercial herbicide
16.07.2018 | UCLA Samueli School of Engineering
Advance warning system via cell phone app: Avoiding extreme weather damage in agriculture
12.07.2018 | Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e.V.
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences