Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Changing Climate May Make 'Super Weed' Even More Powerful

05.06.2009
Researchers at the University of Delaware have discovered a new reason why the tall, tasseled reed Phragmites australis is one of the most invasive plants in the United States. The UD research team found that Phragmites delivers a one-two chemical knock-out punch to snuff out its victims, and the poison becomes even more toxic in the presence of the sun's ultraviolet rays.

Researchers at the University of Delaware have discovered a new reason why the tall, tasseled reed Phragmites australis is one of the most invasive plants in the United States.

The UD research team found that Phragmites delivers a one-two chemical knock-out punch to snuff out its victims, and the poison becomes even more toxic in the presence of the sun's ultraviolet rays.

The study, which is published in the June issue of the scientific journal Plant Signaling & Behavior, is believed to be the first to report the effects of UV-B radiation on plant allelopathy, the production of toxins by a plant to ward off encroachment by neighboring plants.

The authors include Thimmaraju Rudrappa, a former postdoctoral researcher at UD who is now a research scientist at the DuPont Company; Harsh Bais, assistant professor of plant and soil sciences; Yong Seok Choi, postdoctoral researcher in the Department of Chemical Engineering; Delphis Levia and David R. Legates, both associate professors in the Department of Geography; and Kelvin Lee, Gore Professor of Engineering and director of the Delaware Biotechnology Institute.

The research was conducted in Delaware wetlands and in Bais's lab at the Delaware Biotechnology Institute, a major center for life sciences research at the University of Delaware.

“The toxin secreted by Phragmites is degraded by sunlight -- ultraviolet rays -- and causes severe deleterious effects on other native plants,” Bais said.

“Our research also addresses the growing questions of increased UV-B incidences because of global warming and its ultimate effect on plants. In this case, an invasive plant is accidentally utilizing the changed global conditions for its survival and invasion,” Bais noted.

Two years ago, Bais led a study which discovered that Phragmites actively secretes gallic acid to kill off plants and take over new turf. Gallic acid, also known as 3,4,5-trihydroxybenzoic acid, is used for tanning leather, making dyes and inks, and formulating astringents, among other applications.

In this research, the scientists found that the gallic acid released by Phragmites is degraded by ultraviolet light to produce another toxin, mesoxalic acid, effectively hitting susceptible plants and seedlings with a double-whammy.

The mesoxalic acid triggers a similar “cellular death cascade” in victim plants as gallic acid does, Bais said, destroying the tubulin and actin, the structural protein in the roots, within minutes of exposure.

The scientific team detected the biological concentrations of mesoxalic acid in Delaware wetlands, in stands of both exotic and native Phragmites australis. The study highlights the persistence of the photo-degraded phytotoxin, particularly potent in the exotic species of the plant, and its enhanced effects against the native species of Phragmites, which is becoming increasingly endangered in the United States.

Walnut trees, pine trees, ferns and sunflowers are among the plants that release harmful chemicals to prevent other plants from growing too close to them.

However, Phragmites uses this strategy not so much to keep other plants away, but to aggressively conquer them and invade new territory, Bais said.

Funding for the project was provided by the University of Delaware Research Foundation.

Tracey Bryant | Newswise Science News
Further information:
http://www.udel.edu

More articles from Agricultural and Forestry Science:

nachricht Advance warning system via cell phone app: Avoiding extreme weather damage in agriculture
12.07.2018 | Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e.V.

nachricht Fishy chemicals in farmed salmon
11.07.2018 | University of Pittsburgh

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: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>