Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Wild Grasses and Man-Made Wheats Advance Research Capabilities

04.05.2005


Getting resistance to the latest biotype of greenbug or rust in wheat may require some bridge building.



Dr. Jackie Rudd, associate professor at the Texas A&M University System Agricultural Research and Extension Center and state wheat breeder, is looking at wild grass species and synthetic wheats for possible solutions.

"We’re looking for new unique sources of resistance to various biotic and abiotic stresses," Rudd said. "I’m being forced to find broader gene pools to bring in the genetic variability I believe is necessary for the gene pool here."


Karnal bunt, new races of Hessian fly, new leaf rust, stripe rust and Russian wheat aphid, as well as the need for more drought tolerance present challenges, he said. Progress in traditional breeding has been slow due to limited genetic variability for these traits.

Two projects growing in the Texas Agricultural Experiment Station greenhouses in Vernon and Bushland are designed to increase the genetic variability. These projects are being funded by the Texas Wheat Producers Board.

"My preference is to cross wheat with wheat," Rudd said. "The best chance for success is to cross High Plains wheat with High Plains wheat. But to get genetic variability, you cross state lines or even into other countries. The next step would be to cross species, if the desired traits can’t be obtained in a wheat-to-wheat cross."

A wild grass collection being mined for its genetics has 716 lines of wheat relative species. The grasses originated in Turkey and were collected in 1992 as a joint project between Texas A&M University and Centro Internacional de Mejoramiento de Maiz y Trigo, (The International Maise and Wheat Improvement Center) better known as CIMMYT.

"This is a gold mine of untapped genetics," Rudd said. "They can be tapped directly through laboratory crosses, but it is difficult."

The researcher must pollinate from a wild species to a hexaploid wheat and then rescue and nurture the developing embryo to get a plant, he said. Hexaploid wheat has three genomes or sets of chromosomes. This is the makeup of the typical bread wheat.

After such a cross, the initial plant will have genetic abnormalities. A series of crosses back to the hexaploid wheat is necessary before the desired trait from the wild species is expressed without any genetic abnormalities.

The second part of Rudd’s research, working with synthetic or man-made hexaploid wheats, provides a more accessible bridge to the wild species, he said.

Most synthetic hexaploid wheats are crosses between Durum (pasta-type) wheat, which has two genomes or sets of chromosomes, and Aegilops Tauchii or goat grass, Rudd said.

The synthetic hexaploid made from this initial cross is generally wild and unuseable, except as a bridge to the wild species, he said.

"Valuable genetics are lost in the direct cross with the wild grass due to genetic abnormalities," Rudd said. "With synthetic hexaploids, the full compliment of wild relative genes is available for selection."

Researchers in Bushland and Vernon are studying synthetic hexaploids already developed through CIMMYT. Crosses between Texas winter wheat and 117 CIMMYT synthetics have already been made and another 1,100 crosses are expected to be made available to U.S. researchers, he said.

"We want to look at them for the forage characteristics they may offer, which have not been evaluated," Rudd said. "They have been shown to have large, strong seed for rapid stand establishment and early growth in the fall."

These synthetic spring wheat varieties must be backcrossed to make them winter wheats, he said. Then they can be looked at for other characteristics.

"If we find something useful in the wild, we may make a synthetic hexaploid from it, or directly cross into wheat," Rudd said.

"Through traditional genetic variability we’ve been able to gain 1 percent a year in grain yield," he said. "Can we double our genetic gain by doubling our variability?"

CIMMYT predicted that within a few years, more than one-half of its advance lines of wheat will trace back to a synthetic wheat. And that’s from a project started less than 20 years ago, in a world where breeders spend up to 15 years trying to get a desired trait in a line of wheat.

Kay Ledbetter | EurekAlert!
Further information:
http://www.ag.tamu.edu

More articles from Agricultural and Forestry Science:

nachricht Filling intercropping info gap
16.11.2017 | American Society of Agronomy

nachricht Climate change, population growth may lead to open ocean aquaculture
05.10.2017 | Oregon State University

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>