Navigation Links
Resistance gene found against Ug99 wheat stem rust pathogen

MANHATTAN, Kan. -- The world's food supply got a little more plentiful thanks to a scientific breakthrough.

Eduard Akhunov, associate professor of plant pathology at Kansas State University, and his colleague, Jorge Dubcovsky from the University of California-Davis, led a research project that identified a gene that gives wheat plants resistance to one of the most deadly races of the wheat stem rust pathogen -- called Ug99 -- that was first discovered in Uganda in 1999. The discovery may help scientists develop new wheat varieties and strategies that protect the world's food crops against the wheat stem rust pathogen that is spreading from Africa to the breadbaskets of Asia and can cause significant crop losses.

Other Kansas State University researchers include Harold Trick, professor of plant pathology; Andres Salcedo, doctoral candidate in genetics; and Cyrille Saintenac, a postdoctoral research associate currently working at the Institut National de la Recherche Agronomique in France. The project was funded by the U.S. Department of Agriculture and Borlaug Global Rust Initiative.

The team's study, "Identification of Wheat Gene Sr35 that Confers Resistance to Ug99 Stem Rust Race Group," appears in the journal Science.

It identifies the stem rust resistance gene named Sr35, and appears alongside a study from an Australian group that identifies another effective resistance gene called Sr33.

"This gene, Sr35, functions as a key component of plants' immune system," Akhunov said. "It recognizes the invading pathogen and triggers a response in the plant to fight the disease."

Wheat stem rust is caused by a fungal pathogen. According to Akhunov, since the 1950s wheat breeders have been able to develop wheat varieties that are largely resistant to this pathogen. However, the emergence of strain Ug99 in Uganda in 1999 devastated crops and has spread to Kenya, Ethiopia, Sudan and Yemen, though has yet to reach the U.S.

"Until that point, wheat breeders had two or three genes that were so efficient against stem rust for decades that this disease wasn't the biggest concern," Akhunov said. "However, the discovery of the Ug99 race of pathogen showed that changes in the virulence of existing pathogen races can become a huge problem."

As a first line of defense, wheat breeders and researchers began looking for resistance genes among those that had already been discovered in the existing germplasm repositories, he said.

"The Sr35 gene was one of those genes that was discovered in einkorn wheat grown in Turkey," Akhunov said. "Until now, however, we did not know what kind of gene confers resistance to Ug99 in this wheat accession."

To identify the resistance gene Sr35, the team turned to einkorn wheat that is known to be resistant to the Ug99 fungal strain. Einkorn wheat has limited economic value and is cultivated in small areas of the Mediterranean region. It has been replaced by higher yielding pasta and bread wheat varieties.

Researchers spent nearly four years trying to identify the location of the Sr35 gene in the wheat genome, which contains nearly two times more genetic information than the human genome.

Once the researchers narrowed the list of candidate genes, they used two complimentary approaches to find the Sr35 gene. First, they chemically mutagenized the resistant accession of wheat to identify plants that become susceptible to the stem rust pathogen.

"It was a matter of knocking out each candidate gene until we found the one that made a plant susceptible," Akhunov said. "It was a tedious process and took a lot of time, but it was worth the effort."

Next, researchers isolated the candidate gene and used biotechnical approaches to develop transgenic plants that carried the Sr35 gene and showed resistance to the Ug99 race of stem rust.

Now that the resistance gene has been found, Akhunov and colleagues are looking at what proteins are transferred by the fungus into the wheat plants and recognized by the protein encoded by the Sr35 gene. This will help researchers to better understand the molecular mechanisms behind infection and develop new approaches for controlling this devastating pathogen.


Contact: Eduard Akhunov
Kansas State University

Related biology news :

1. Antibiotics: Change route of delivery to mitigate resistance
2. An article in Cell reveals a new resistance mechanism to chemotherapy in breast and ovarian cancer
3. New agent inhibits HCV replication in mouse models -- No resistance seen
4. Resistance to last-line antibiotic makes bacteria resistant to immune system
5. Biosensor that detects antibiotic resistance brings us one step closer to fighting superbugs
6. Study confirms everolimus can overcome trastuzumab resistance in HER-2 positive early breast cancer
7. Cheers to better beer and disease resistance
8. New study identifies unique mechanisms of antibiotic resistance
9. Study: Widespread test-and-treat HIV policies could increase dangerous drug resistance
10. American Academy of Microbiology releases resistance report
11. COMBACTE: A new step in the fight against resistance to antibiotics
Post Your Comments:
(Date:4/26/2016)... and LONDON , ... Finacle, part of EdgeVerve Systems, a product subsidiary ... Onegini today announced a partnership to integrate the ...      (Logo: ) ... provide their customers enhanced security to access and ...
(Date:4/15/2016)... April 15, 2016 Research ... Gait Biometrics Market 2016-2020,"  report to their offering.  ... ) , ,The global gait biometrics market is ... during the period 2016-2020. Gait analysis ... can be used to compute factors that are ...
(Date:3/31/2016)... 2016  Genomics firm Nabsys has completed a financial ... Bready , M.D., who returned to the company in ... leadership team, including Chief Technology Officer, John Oliver ... Nurnberg and Vice President of Software and Informatics, ... Dr. Bready served as CEO of Nabsys from ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... Mass. , June 23, 2016   ... development of novel compounds designed to target cancer ... napabucasin, has been granted Orphan Drug Designation from ... the treatment of gastric cancer, including gastroesophageal junction ... stemness inhibitor designed to inhibit cancer stemness pathways ...
(Date:6/23/2016)... ... June 23, 2016 , ... Charm Sciences, Inc. is pleased ... received AOAC Research Institute approval 061601. , “This is another AOAC-RI approval of ... Salter, Vice President of Regulatory and Industrial Affairs. “The Peel Plate methods perform ...
(Date:6/23/2016)... ... 2016 , ... Supplyframe, the Industry Network for electronics hardware ... . Located in Pasadena, Calif., the Design Lab’s mission is to bring together ... built and brought to market. , The Design Lab is Supplyframe’s physical representation ...
(Date:6/23/2016)... June 23, 2016  Blueprint Bio, a company dedicated ... the medical community, has closed its Series A funding ... . "We have received a commitment from ... we need to meet our current goals," stated ... the runway to complete validation on the current projects ...
Breaking Biology Technology: