UZH plant researchers have tested newly developed wheat lines with improved resistance in field trials. They have demonstrated that a combination of two variations of a resistance gene provides wheat with better protection against the fungal disease.
A decent wheat harvest requires robust wheat. However, wheat crops are often infected by fungal diseases such as powdery mildew. For several years now, UZH researchers have been investigating a wheat gene that confers resistance to powdery mildew (Blumeria graminis f. sp. tritici).
The gene, called the Pm3 resistance gene, exists in different variations, so called alleles. In previous studies, plant researcher Beat Keller and his team demonstrated that single Pm3 alleles are able to confer resistance against powdery mildew fungi.
And yet, a single resistance gene can quickly lose its effectiveness. Thus when it comes to plant breeding, it is important to combine multiple resistance genes. This is exactly what researchers at UZH have now tested in field trials using transgenic wheat lines.
Combination of two Pm3 variations increases powdery mildew resistance
The researchers created new wheat lines by crossbreeding transgenic Pm3 lines (see box). This resulted in four new wheat lines, each containing two different Pm3 gene variations. “These four new wheat lines showed improved resistance against powdery mildew in field trials compared with their parental lines – during the field seasons 2015 to 2017,” explains Teresa Koller, lead author of the study.
No negative effects on wheat yield
Back in the laboratory, the scientists proved that the parental lines’ gene activity is added up in the newly created lines. Each Pm3 allele in the four new lines displayed the same activity as in the parental line, which results in increased overall activity, since it came from two different gene variations. “The improved resistance against powdery mildew is the result of the increased total transgene activity as well as the combination of the two Pm3 gene variations,” summarizes Teresa Koller. The high overall activity of resistance genes did not cause any negative effects for the development of the wheat or its yield.
Application in modern wheat breeding
The findings of these trials improve our general knowledge of the immune system of plants, and in particular of fungal disease resistance of wheat. Besides contributing to fundamental research in the area of plants’ immune systems, the findings can also be applied in wheat breeding. Thanks to the precise testing of Pm3 alleles, the best variations and combinations are identified and can then be used directly in traditional breeding by crossbreeding them into modern wheat varieties.
Teresa Koller, Susanne Brunner, Gerhard Herren, Severine Hurni, and Beat Keller. Pyramiding of transgenic Pm3 alleles in wheat results in improved powdery mildew resistance in the field. Theoretical and Applied Genetics. January 11, 2018. DOI: 10.1007/s00122-017-3043-9
Function of the Pm3 resistance gene
The Pm3 gene is the “blueprint” for a protein that can receive signals in the plant cell, i.e. a receptor. It is able to recognize avirulent proteins, or AvrPm3 for short, of the powdery mildew fungus. The receptor triggers the plant cell’s death as soon as the harmful fungus attempts to inject the AvrPm3 protein into the plant cell. By killing off the attacked cell, the rest of the plant is protected against the fungus. Different Pm3 gene variations, or Pm3 alleles, encode different variations of the receptor. These receptor variations are able to recognize different AvrPm3 proteins of the powdery mildew fungus.
Prof. Beat Keller and his team have identified various Pm3 gene variations in powdery mildew-resistant wheat varieties from across the world. To assess the function and effectiveness of the different Pm3 gene variations, they were genetically engineered into the genome of the spring wheat variety Bobwhite. Bobwhite wheat lacks its own functioning Pm3 gene and is very susceptible to powdery mildew. The transgenic Bobwhite wheat lines, each containing a single Pm3 gene variation, were assessed in field trials as part of the National Research Program NFP59 between 2008 and 2010. The findings of these trials were published in 2011 and 2012.
Prof. Beat Keller
Department of Plant and Microbial Biology
University of Zurich
Phone +41 44 634 82 30
Nathalie Huber | Universität Zürich
Cereals use chemical defenses in a multifunctional manner against different herbivores
06.12.2018 | Max-Planck-Institut für chemische Ökologie
Can rice filter water from ag fields?
05.12.2018 | American Society of Agronomy
Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.
Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
17.12.2018 | Studies and Analyses
17.12.2018 | Life Sciences
17.12.2018 | Power and Electrical Engineering