Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Laurel Wilt of Redbay and Sassafras: Will Avocados be Next?

04.04.2008
Scientists with the USDA Forest Service Southern Research Station (SRS), Iowa State University, and the Florida Division of Forestry have provided the first description of a fungus responsible for the wilt of redbay trees along the coasts of South Carolina, Georgia, and Florida.

In the February issue of Plant Disease, SRS plant pathologist Stephen Fraedrich and fellow researchers provide results from their assessment of the fungus, the beetle that carries it, and their combined effect on redbay and other members of the laurel family, including sassafras, spicebush, and avocado.

Extensive mortality of redbay, an attractive evergreen tree common along the coasts of the southeastern United States, has been observed in South Carolina and Georgia since 2003. Though the wilt was at first attributed to drought, the cause was soon found to be a fungal pathogen and the exotic redbay ambrosia beetle, Xyleborus glabratus, a native to Southeast Asia that was first found in the area in 2002. Many ambrosia beetles carry species of fungi as food for their larvae; a previously undescribed fungus in the genus Raffaelea is a fungal symbiont of this ambrosia beetle.

To determine if the fungus was the cause of the wilt, Fraedrich and his colleagues inoculated redbay trees and containerized seedlings with the Raffaelea fungus; the plants died within 5 to 12 weeks. To connect fungus and beetle, they also exposed redbay seedlings to X. glabratus beetles; the ambrosia beetles tunneled into almost all of the plants, causing 70 percent of them to die. The researchers found the fungus in 91 percent of the beetle-attacked plants.

"These experiments showed that the Raffaelea species we isolated from wilted trees and from the redbay ambrosia beetle is the cause of redbay wilt," says Fraedrich. "The fungus, which is routinely isolated from the heads of X. glabratus ambrosia beetles, is apparently introduced into healthy redbay during beetle attacks on stems and branches."

Redbays are common along Southeastern coast, and both residents and visitors are disturbed by the massive mortality. Deer browse on the evergreen foliage of the tree, and the fruit is eaten by songbirds, wild turkeys, and other animals. Redbay is also the primary host for the larvae of the palamedes swallowtail butterfly. But it’s not just the redbays that plant pathologists are worried about.

"The fungus we isolated has also been associated with the death of other trees in the laurel family, and the Raffaelea sp. has been isolated from wilted sassafras, pondberry and pondspice," says Fraedrich. "Our inoculation studies have shown that the fungus is deadly to these species as well as to spicebush, and avocado, but not to red maple."

The researchers concluded that there is reason to be concerned about the spread of the wilt to other members of the laurel family, which are common components in forests across the United States and other areas of the Americas. Recent studies have shown that California laurel, a West Coast species in the Lauraceae, is also susceptible to laurel wilt.

"We are also very concerned about avocado, a species indigenous to Central America which is grown commercially in Florida and alifornia," says Fraedrich. "Our evaluation of avocado indicates that it is also susceptible to laurel wilt, and the wilt has been found recently in avocado trees growing in a residential area of Jacksonville, Florida."

For more information: Stephen Fraedrich at 706-559-4273 or sfraedrich@fs.fed.us

Read more about laurel wilt on the Forest Health Protection, Southern Region website at http://www.fs.fed.us/r8/foresthealth/laurelwilt/index.shtml

Stephen Fraedrich | EurekAlert!
Further information:
http://www.fs.fed.us

More articles from Agricultural and Forestry Science:

nachricht Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli
26.04.2017 | University of the Basque Country

nachricht New data unearths pesticide peril in beehives
21.04.2017 | Cornell 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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>