Navigation Links
UD plant biologists uncover top wetland plant's hidden weapon
Date:10/12/2007

Scientists at the University of Delaware have uncovered a hidden weapon that one of the most invasive wetland plants in the United States uses to silently and efficiently bump off its neighbors.

The invasive strain of Phragmites australis, or common reed, believed to have originated in Eurasia, exudes from its roots an acid so toxic that the substance literally disintegrates the structural protein in the roots of neighboring plants, thus toppling the competition.

Phragmites is taking over the marsh world, said UD plant biologist Harsh Bais. It's a horticultural disaster.

In Delaware alone, the tall, tasseled grass has overtaken tens of thousands of acres of wetlands, decreasing biodiversity, reducing the food and habitat available to wildlife, and altering wetland hydrology, transforming marshes once dissected by tidal creeks and open pools into much drier systems with dense monocultures of the plant.

Bais, who led the project, is an assistant professor of plant and soil sciences in UD's College of Agriculture and Natural Resources and holds an appointment at the Delaware Biotechnology Institute. His collaborators included postdoctoral researcher Thimmaraju Rudrappa, undergraduate student Justin Bonstall, and marine botanists John Gallagher and Denise Seliskar, who co-direct the Halophyte Biotechnology Center in UD's College of Marine and Earth Studies.

The results of the research are reported in the latest issue of the Journal of Chemical Ecology.

Bais is an expert on allelopathy, in which one plant produces a chemical to inhibit the growth of another plant. He refers to these plants with the capability to wage chemical warfare as natural killers.

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.

We've seen this capability in a number of invasive plants that have come from Eurasia, such as garlic mustard, Bais said. The roots exude a toxin that kills native plants.

In laboratory analyses at the Delaware Biotechnology Institute, Rudrappa and Bais used activated charcoal, the material in aquarium filters, to sequester secretions from both invasive and native Phragmites plants. The charcoal attracts and traps organic chemicals.

The scientists identified the toxin produced by Phragmites as 3,4,5-trihydroxybenzoic acid. Also known as gallic acid, it is used for tanning leather, to formulating astringents.

It's nasty stuff, Bais said. If you get some of it on your skin, you definitely know it.

The toxin works, Bais said, by targeting tubulin, the structural protein that helps plant roots to maintain their cellular integrity and grow straight in the soil. Within 10 minutes of exposure to the toxin in the lab, the tubulin of a marsh plant under siege starts to disintegrate. Within 20 minutes, the structural material is completely gone.

When the roots collapse from the acid, the plant loses its integrity and dies, Bais noted. It's like having a building with no foundation--it's on its way to self-destruction.

The native Phragmites also secretes the toxin, but the exotic strain releases much higher concentrations, which could be a key to its dominance, Bais said.

Today in Delaware, stands of native Phragmites are few and far between. Bais credits Gallagher and Seliskar, who have conducted extensive research on the plant, for growing sterile cultures of the native and exotic strains for his lab tests.

This research reveals another weapon in the arsenal that Phragmites uses to overtake marshland, Seliskar said.

Screening large numbers of marsh plants to identify those that are naturally resistant to invasive Phragmites may be one avenue for preserving the native strain, as well as controlling the invasive's spread, Bais noted.

With the current discovery in hand, Bais said he hopes to pursue further research to pinpoint exactly how the invasive Phragmites has become such a super weed. Such information could help scientists and environmental managers gain a foothold in halting Phragmites' rapid advance across the United States.

We now know this plant secretes a toxin underground, but could it have a partner in crime" Bais asks. Could there be some kind of microbe, a deleterious pathogen, that is associated with this plant" And does this plant use changing environmental systems to its advantage" We just don't know the answers yet, but we'd like to find out.


'/>"/>

Contact: Tracey Bryant
tbryant@udel.edu
302-831-8185
University of Delaware
Source:Eurekalert

Related biology news :

1. Quantum Dots Research Leads to New Knowledge about Protein Binding in Plants
2. Key molecule in plant photo-protection identified
3. Plants, animals share molecular growth mechanisms
4. Plants respond similarly to signals from friends, enemies
5. Affymetrix Unveils Plans to Double Plant and Animal Genome Microarray Offering
6. Transplantation Of Monkey Embryonic Stem Cells Reverses Parkinson Disease In Primates
7. Emory Eye Center Implants Its First Retinal Chips In Patients With Retinitis Pigmentosa
8. Plant hemoglobins: Oxygen handlers critical for nitrogen fixation
9. Circles Of DNA Might Help Predict Success Of Stem Cell Transplantation
10. Plants defy Mendels inheritance laws, may prompt textbook changes
11. Antibodies from plants protect against anthrax
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/19/2016)... 2016 The new GEZE SecuLogic ... web-based "all-in-one" system solution for all door components. It ... the door interface with integration authorization management system, and ... The minimal dimensions of the access control and the ... installations offer considerable freedom of design with regard to ...
(Date:4/14/2016)... , April 14, 2016 ... Malware Detection, today announced the appointment of Eyal ... new role. Goldwerger,s leadership appointment comes at ... heels of the deployment of its platform at several ... biometric technology, which discerns unique cognitive and physiological factors, ...
(Date:3/31/2016)... R.I. , March 31, 2016  Genomics firm ... of founding CEO, Barrett Bready , M.D., who ... members of the original technical leadership team, including Chief ... President of Product Development, Steve Nurnberg and Vice President ... returned to the company. Dr. Bready served ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... Cancer experts ... they believe could be a new and helpful biomarker for malignant pleural mesothelioma. ... here to read it now. , Biomarkers are components in the blood, ...
(Date:6/27/2016)... Ginkgo Bioworks , a leading organism design company ... as one of the World Economic Forum,s Technology ... companies. Ginkgo Bioworks is engineering biology to manufacture ... the nutrition, health and consumer goods sectors. The ... Fortune 500 companies to design microbes for their ...
(Date:6/23/2016)... ... June 23, 2016 , ... Mosio, a leader ... “Clinical Trials Patient Recruitment and Retention Tips.” Partnering with experienced clinical research professionals, ... providing practical tips, tools, and strategies for clinical researchers. , “The landscape of ...
(Date:6/23/2016)... -- Houston Methodist Willowbrook Hospital has signed a ... serve as their official health care provider. As ... provide sponsorship support, athletic training services, and most ... athletes and families. "We are excited ... to bring Houston Methodist quality services and programs ...
Breaking Biology Technology: