Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Plant detectives seek sources of invasive trees

13.08.2002


Tamarix invading the southwest



Like modern day Sherlock Holmeses, plant biologists at Washington University in St. Louis have donned their deerstalkers to get to the bottom of some botanical mysteries.
Barbara A. Schaal, Ph.D., Washington University professor of biology and her graduate students use DNA sequences to reveal information on historical events. Schaal has traced the origins of cassava using molecular techniques, and now is using systematics and phylogeography to document the role of hybridization and introgression in the evolution of Phlox species and to trace the Eurasian source of invasive Tamarix species in the United States.

The Tamarix species, commonly called saltcedar, are environmental threats that have invaded the arid southwest and are contributing to the drying up of creeks and streams in that water-threatened area. Over a million acres are now infested with saltcedar monocultures along streams and riverbeds. The salt cedars’ long taproots suck up salty ground water and drop salt-crusted leaves on the soil surface. This makes it almost impossible for native plants to take root. The loss of native plants also decreases the insect and bird biodiversity.



Schaal’s graduate student, John Gaskin, has used DNA sequences to identify which species are here and to document hybridization. Their DNA analyses also help them pinpoint where the plants may have originated in Eurasia. Earlier USDA studies show that an Arizona saltcedar will not be eaten by certain Asian insects known to like saltcedars; these insects, instead, prefer plants that grow in Texas or New Mexico. So, there are different kinds of the plants in different areas.

So far Schaal and Gaskin have found that the most common invasive here is a hybrid of two species that do not grow in the same areas of Asia, and thus is a novel plant genotype. These results will help USDA biological control researchers determine which insects to import in the future to help control the invasion, but caution that any novel hybrid plants may prove to be unpalatable to species-specific insects, since they did not evolve with them.

Schall and Gaskin published their results in the Proceedings of the National Academy of Sciences (PNAS), the week of Aug. 12-16, 2002.

Tamarix is the second most evasive plant in the United States. Purple loosestrife (Lythrum salicaria) is number one and a big problem in northern areas. Invasive plants are second only to habitat loss in contributing to loss of biodiversity.

PNAS WRITE-UP

Hybrid Plants Run Rampant

Previously undetected hybrids are a major component of a non-native plant invasion that has taken over more than 600,000 hectares of U.S. wetlands and riparian areas, report the authors of article #4032. Eurasian Tamarix, commonly known as saltcedar or tamarisk, was first introduced to the United States in the 1800s for the purposes of shade and erosion control. Since then, according to a genetic analysis performed by authors John Gaskin and Barbara Schaal, two of the introduced species of Tamarix have interbred to create a hybrid that may be resistant to biological control agents currently under development. In their native environments, the two species rarely overlap--T. ramosissima was found almost exclusively west of central China, while T. chinensis was found primarily to the east--but in the U.S., the two species have been placed in close proximity to each other and given ample opportunity to hybridize. By analyzing genetic variations among more than 250 plants gathered in the U.S. and Eurasia, the authors found that overall diversity is higher in Eurasia, but the proportion of novel hybrids is higher in the U.S. In fact, the most common plant in the U.S. invasion is a hybrid of T. ramosissima and T. chinensis. The authors also found that a small region within the Republic of Georgia and Azerbaijan contains all of the genetic variation of T. ramosissima common to both the U.S. and Eurasia, a discovery that could aid in the development of effective

biological controls. The authors note that Tamarix continues to spread across the U.S. at a rate of about 18,000 hectares per year, displacing other species and altering the hydrology of watercourses in fragile, arid environments.

"Hybrid Tamarix widespread in U.S. invasion and undetected in native Asian range," by John F. Gaskin and Barbara A. Schaal


Links: For more information on Tamarix or the current biological control project, see http://www.invasivespecies.gov/profiles/saltcedar.shtml and http://wric.ucdavis.edu/saltcedar/grant/research.html

Missouri Exotic Invasive Plant Page: http://www.mobotgradstudents.org/~mobot/MOEPPC/MOEIPP1.html
Gaskin website: http://www.mobotgradstudents.org/~mobot/Gaskin/johnpage.html

Tony Fitzpatrick | EurekAlert!
Further information:
http://www.invasivespecies.gov/profiles/saltcedar.shtml
http://wric.ucdavis.edu/saltcedar/grant/research.html
http://www.mobotgradstudents.org/~mobot/MOEPPC/MOEIPP1.html

More articles from Ecology, The Environment and Conservation:

nachricht Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus

nachricht How to detect water contamination in situ?
22.09.2016 | Tomsk Polytechnic University (TPU)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: New welding process joins dissimilar sheets better

Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of light metals.
Scientists at the University of Stuttgart have now developed two new process variants that will considerably expand the areas of application for friction stir welding.
Technologie-Lizenz-Büro (TLB) GmbH supports the University of Stuttgart in patenting and marketing its innovations.

Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of...

Im Focus: First quantum photonic circuit with electrically driven light source

Optical quantum computers can revolutionize computer technology. A team of researchers led by scientists from Münster University and KIT now succeeded in putting a quantum optical experimental set-up onto a chip. In doing so, they have met one of the requirements for making it possible to use photonic circuits for optical quantum computers.

Optical quantum computers are what people are pinning their hopes on for tomorrow’s computer technology – whether for tap-proof data encryption, ultrafast...

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

European Health Forum Gastein 2016 kicks off today

28.09.2016 | Event News

Laser use for neurosurgery and biofabrication - LaserForum 2016 focuses on medical technology

27.09.2016 | Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

 
Latest News

New imaging technique in Alzheimer’s disease - opens up possibilities for new drug development

28.09.2016 | Medical Engineering

Innovate coating extends the life of materials for industrial use

28.09.2016 | Materials Sciences

Blockchain Set to Transform the Financial Services Market

28.09.2016 | Business and Finance

VideoLinks
B2B-VideoLinks
More VideoLinks >>>