News / Science & Technology

    Genes Found to Fight Wheat Disease

    Varying stem rust epidemics on wheat stems (Photo: Evans Lagudah & Zakkie Pretorius)
    Varying stem rust epidemics on wheat stems (Photo: Evans Lagudah & Zakkie Pretorius)
    Scientists have isolated two genes that protect wheat plants from a disease that threatens the crop worldwide.

    In two articles in the journal Science, researchers describe a pair of genes that confer resistance to a new, virulent form of a fungal disease called stem rust.

    At its worst, stem rust can wipe out nearly an entire wheat field. After a 1953 outbreak destroyed 40 percent of the U.S. spring wheat harvest, scientists bred new varieties with resistance to the disease.

    That solved the problem for several decades.

    Out of Africa

    “But then, just in 1999, a new race evolved in Africa," says Kansas State University plant disease expert Eduard Akhunov. "And they found that it overcomes all these resistance genes.”

    First found in Uganda, this new "race" - a strain called Ug99 - has spread from South Africa to Iran.

    But experts are worried the fungus won’t stop there. Nearly all of the world’s commercial wheat varieties are susceptible to it.

    A global effort is under way to create new, Ug99-proof varieties.

    Akhunov is co-author of one article. He says both genes described in the new articles come from wheat’s wild relatives.

    New alarm system

    “Our gene is some kind of surveillance molecule that will try to sense if [the] pathogen is invading or not,” Akhunov says.

    He says wheat plants don’t sense that Ug99 is invading because the fungal proteins that used to set off alarms have mutated.

    The newly described genes restore the wheat plant’s ability to recognize the invading fungus, says plant biologist Jan Dvorak at the University of Califoria at Davis, co-author of the other new article.

    “The gene for resistance is a gene which gives the wheat plant a sensor again," says Dvorak. "It says, ‘Ah, we missed this guy.’ And the wheat plant suddenly is able to see again.”

    Breeding better wheat

    Eduard Akhunov says researchers could use genetic engineering to quickly put both genes into wheat plants at the same time. But he says now may not be the time because many people don’t trust gene-splicing technology.    

    “Maybe in the future," Akhunov says. "Because until the public is ready for that, I don’t think there is a way of using that approach.”

    Others say genetic engineering may not save much time because of advances in conventional breeding. When conventional breeders mate two plants, they use genetic markers to find offspring with the genes they want.

    “Now you have the perfect markers," says Jose Costa, head of grain crop research at the U.S. Department of Agriculture. "It makes things a lot easier and more targeted.”

    Wheat varieties resistant to Ug99 have been released in several South Asian countries. More are on the way. But experts warn that diseases will continue to evolve, and fighting them is a never-ending battle.

    You May Like

    Leaving Scalia Replacement to 2017 Would Mean Unusually Long Vacancy

    History of high court shows Obama not in unique situation during final year of presidency

    US Fact Checkers Debunk Some Republican Candidate Claims 

    Slim evidence for several claims made by Republican presidential candidates at their last debate ahead of next Saturday's key nominating election in South Carolina

    Uganda Presidential Debate a Small Victory for Democracy

    In homes and bars across country, Ugandans were fixated on their screens as eight political candidates running for president took part in national debate

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    New Technology Aims to Bring Election Transparency to Ugandai
    X
    Serginho Roosblad
    February 12, 2016 9:29 PM
    A team of recent graduates from Uganda’s Makerere University has created a mobile application designed to help monitor elections and expose possible rigging. The developers say the app, called E-Poll, will make Uganda's democratic process fairer. From Kampala, VOA's Serginho Roosblad reports.
    Video

    Video New Technology Aims to Bring Election Transparency to Uganda

    A team of recent graduates from Uganda’s Makerere University has created a mobile application designed to help monitor elections and expose possible rigging. The developers say the app, called E-Poll, will make Uganda's democratic process fairer. From Kampala, VOA's Serginho Roosblad reports.
    Video

    Video Refugees in Kenya Vie to Compete in Rio Olympics

    In Kenya, refugees from other African nations are training at a special camp and competing for a limited number of slots in this year's Rio Olympics under the flag of the International Olympic Committee (IOC). As Lenny Ruvaga reports from Ngong, this is a first in Olympic history.
    Video

    Video Gateway to Mecca: Historical Old Jeddah

    Local leader Sami Nawar's family has been in the Old City of Jeddah for hundreds of years and takes us on a tour of this ancient route to Mecca, also believed to be the final resting place of Adam's wife, Eve.
    Video

    Video Two-thirds of World Faces Water Shortage

    Four billion people — or two out of every three on the planet — do not have enough water to meet their basic needs. That is far greater than previously thought, according to a new study that presents a more accurate picture of the problem. As VOA's Rosanne Skirble reports, the findings will help policymakers and the public craft solutions to address the threat.
    Video

    Video As Refugees Perish, Greek Graveyards Fill

    Aid workers on the Greek island of Lesbos say they are struggling to bury the increasing number of bodies of refugees that have been recovered or washed up ashore in recent months.  The graveyards are all full, they say, yet as tens of thousands of people clamor to get out of Syria, it is clear refugees will still be coming in record numbers. For VOA, Hamada Elrasam reports from Lesbos, Greece.
    Video

    Video Russia Bristles at NATO Expansion in E. Europe

    Russian Foreign Minister Sergei Lavrov is meeting Friday with the head of NATO after the Western military alliance and the United States announced plans for the biggest military build-up in Europe since the Cold War. Russia has called NATO's moves a threat to stability in Europe. But NATO says the troop rotations and equipment are aimed at reassuring allies concerned about Russia as VOA's Daniel Schearf reports from Moscow.
    Video

    Video To Fight Zika, Scientists Target Mosquitoes

    Mosquitoes strike again. The Zika virus outbreak is just the latest headline-grabbing epidemic carried by these biting pests, but researchers are fighting back with new ways to control them. VOA's Steve Baragona takes a look.
    Video

    Video Mosul Refugees Talk About Life Under IS

    A top U.S. intelligence official told Congress this week that a planned Iraqi-led operation to re-take the city of Mosul from Islamic State militants is unlikely to take place this year. IS took over the city in June 2014, and for the past year and a half, Mosul residents have been held captive under its rule. VOA's Zana Omar talked to some families who managed to escape. Bronwyn Benito narrates his report.
    Video

    Video Scientists Make Progress Toward Better Diabetes Treatment, Cure

    Scientists at two of the top U.S. universities say they have made significant advances in their quest to find a more efficient treatment for diabetes and eventually a cure. According to the International Diabetes Federation, the disease affects more than 370 million people worldwide. VOA’s George Putic reports.
    Video

    Video NATO to Target Migrant Smugglers

    NATO has announced plans to send warships to the Aegean Sea to target migrant smugglers in the alliance's most direct intervention so far since a wave of people began trying to reach European shores.
    Video

    Video Used Books Get a New Life on the Streets of Lagos

    Used booksellers are importing books from abroad and selling them on the streets of Africa's largest city. What‘s popular with readers may surprise you. Chris Stein reports from Lagos.
    Video

    Video After NH Primaries All Eyes on South Carolina

    After Tuesday's primary in New Hampshire, US presidential candidates swiftly turned to the next election coming up in South Carolina. The so-called “first-in-the-South” poll may help further narrow down the field of candidates. Zlatica Hoke reports.
    Video

    Video Smartphone Helps Grow Vegetables

    One day, you may be using your smartphone to grow your vegetables. A Taipei-based company has developed a farm cube — a small, enclosed ecosystem designed to grow plants indoors. The environment inside is automatically adjusted by the cube, but it can also be controlled through an app. VOA's Deborah Block has more on the gardening system.
    Video

    Video Exhibit Turns da Vinci’s Drawings Into Real Objects

    In addition to being a successful artist, Renaissance genius Leonardo da Vinci designed many practical machines, some of which are still in use today, although in different forms. But a number of his projects were never realized — until today. VOA’s George Putic reports.