Featured Research

from universities, journals, and other organizations

Uncovering the mystery of a major threat to wheat

Date:
June 2, 2010
Source:
USDA/Agricultural Research Service
Summary:
Agricultural scientists have solved a longstanding mystery as to why a pathogen that threatens the world's wheat supply can be so adaptable, diverse and virulent.

ARS scientists have discovered that the fungus that causes stripe rust in wheat may use sexual recombination to overcome resistant wheat varieties as fast as they do.
Credit: Photo courtesy of Mary Burrows, Montana State University, Bugwood.org

Agricultural Research Service (ARS) scientists have solved a longstanding mystery as to why a pathogen that threatens the world's wheat supply can be so adaptable, diverse and virulent. It is because the fungus that causes the wheat disease called stripe rust may use sexual recombination to adapt to resistant varieties of wheat.

ARS plant pathologist Yue Jin and his colleagues Les Szabo and Marty Carson at the agency's Cereal Disease Laboratory at St. Paul, Minn., have shown for the first time that stripe rust, caused by Puccinia striiformis, is capable of sexually reproducing on the leaves of an alternate host called barberry, a common ornamental. The fungus also goes through asexual mutation. But sexual recombination offers an advantage because it promotes rapid reshuffling of virulence gene combinations and produces a genetic mix more likely to pass along traits that improve the chances for survival.

Barberry (Berberis spp) is already controlled in areas where wheat is threatened by stem rust, caused by another fungal pathogen. But the work by the ARS team is expected to lead to better control of barberry in areas like the Pacific Northwest, where cool temperatures during most of the wheat growing season make stripe rust a particular threat.

The researchers suspended wheat straw infected with the stripe rust pathogen over barberry plants and found that fungal spores from the wheat infected the barberry. They also took infected barberry leaves, treated them to promote the release of spores, and exposed them to wheat. Tests confirmed that the wheat plants were infected within about 10 days.

The researchers began the study last year after finding infected leaves on barberry plants at two sites on the University of Minnesota campus. They initially thought the symptoms were a sign that the stem rust pathogen had overcome the resistance commonly found in U.S. varieties of barberry.

Instead, they found barberry serving as a sexual or "alternate" host for stripe rust. When the overwintering spores of the stripe rust fungus germinate in the spring, they produce spores that reach barberry leaves, forming structures on the top of the leaves that allow mating between races or strains of the fungus. Spores resulting from this mating can, in turn, infect wheat.

The results were recently published in Phytopathology.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. The original article was written by Dennis O'Brien. Note: Materials may be edited for content and length.


Journal Reference:

  1. Yue Jin, Les J. Szabo, Martin Carson. Century-Old Mystery of Puccinia striiformis Life History Solved with the Identification of Berberis as an Alternate Host. Phytopathology, 2010; 100 (5): 432 DOI: 10.1094/PHYTO-100-5-0432

Cite This Page:

USDA/Agricultural Research Service. "Uncovering the mystery of a major threat to wheat." ScienceDaily. ScienceDaily, 2 June 2010. <www.sciencedaily.com/releases/2010/06/100601151112.htm>.
USDA/Agricultural Research Service. (2010, June 2). Uncovering the mystery of a major threat to wheat. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2010/06/100601151112.htm
USDA/Agricultural Research Service. "Uncovering the mystery of a major threat to wheat." ScienceDaily. www.sciencedaily.com/releases/2010/06/100601151112.htm (accessed August 21, 2014).

Share This




More Plants & Animals News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Possible Ebola Patient in Isolation at California Hospital

Possible Ebola Patient in Isolation at California Hospital

Reuters - US Online Video (Aug. 20, 2014) — A patient who may have been exposed to the Ebola virus is in isolation at the Kaiser Permanente South Sacramento Medical Center. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) — Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Unsustainable Elephant Poaching Killed 100K In 3 Years

Unsustainable Elephant Poaching Killed 100K In 3 Years

Newsy (Aug. 20, 2014) — Poachers have killed 100,000 elephants between 2010 and 2012, as the booming ivory trade takes its toll on the animals in Africa. Video provided by Newsy
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) — Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins