Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biocontrol of wavyleaf thistle being studied in Texas

30.11.2006
BUSHLAND û Wavy leaf thistle was difficult to find along Panhandle highways five years ago. But now the noxious weed can be found moving into pastures, said a Texas Agricultural Experiment Station researcher.

Dr. Jerry Michels, Experiment Station entomologist at Bushland, along with Nagendra Earle, a West Texas A&M University graduate student, began looking at controlling the intruding noxious weed with natural controls about two years ago.

Michels' entomology team travels the highways to Colorado frequently each year to monitor biocontrol work with the U.S. Fish and Wildlife Service. At first, they noticed wavyleaf thistle growing in small clumps along roadsides, Michels said, but in the past few years it seemed to be spreading.

Deciding they wanted to look at possible control measures, he submitted a proposal for a grant to the Joe Skeen Institute for Rangeland Restoration. His team received funding for two years.

In spring 2005, Earle began mapping the infestations across the Panhandle. The highest concentrations were found in the northern Panhandle down to U.S. Interstate 40, he said. Wavyleaf thistle has been found along I-40 from New Mexico to Colorado, but not much to the south.

"Our idea was that it was coming in through vehicle traffic, because it is common in Colorado, Nebraska and Wyoming," Michels said. "Also, thistles love disturbed areas, so any road work could have increased the infestation."

Once it was all mapped, Earle looked for naturally occurring insects that fed off the plant. He found one large beetle that fed on the seed heads, but that beetle was considered an economic pest of sunflowers, so it was undesirable for use as a biocontrol agent, Michels said.

This spring, Earle resurveyed to measure the plant's spread and density, Michels said.

"We're finding it is spreading into pastures and becoming a problem," he said. "We need to continue to monitor it for several years to get a good line on it, but we wanted to start treatments also."

A large patch covering several acres in Hutchinson County was selected as a treatment site, Michels said. Cages were set up with four treatments: no action, mowing, chemical control and biocontrol agents.

The thistle seedhead weevils used for the biocontrol study were collected around Kerrville, where the beetle has been released on wavyleaf thistle with good results, he said. This beetle feeds on the seed heads.

"This preliminary year, the biocontrol seems to be working better than the mowing or chemical control," Michels said.

However, he is going to study a musk thistle rosette weevil used in Colorado to help control musk thistle. This beetle feeds on the root of the plant.

Michels hopes the combination of beetles can control the perennial plant and keep it from resprouting each year.

The musk thistle rosette weevil is found primarily north of Texas where the growing season of thistle is different, Michels said. The problem is trying to gather enough of the beetles in Colorado and bring them to Texas while the plants are still growing.

While the musk thistle rosette weevil hasn't been established in Texas, it has been approved by the U.S. Department of Agriculture for use as a biocontrol. Neither beetle is considered a threat to crops.

"Whenever we do biocontrol work, that is our first concern," Michels said.

The ultimate goal is to get both beetles established in cages on roadside wavyleaf thistle plants at high enough numbers so they can be released around the region to naturally spread, he said.

Another part of the study will be to look at a combination of chemical or mechanical methods with the biocontrol using the beetles, Michels said. The hope is a combination will either kill out the plant or weaken it enough to lessen reproduction.

Dr. Jerry Michels | EurekAlert!
Further information:
http://www.tamu.edu

More articles from Agricultural and Forestry Science:

nachricht Faba fix for corn's nitrogen need
11.04.2018 | American Society of Agronomy

nachricht Wheat research discovery yields genetic secrets that could shape future crops
09.04.2018 | John Innes Centre

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: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Structured light and nanomaterials open new ways to tailor light at the nanoscale

23.04.2018 | Physics and Astronomy

On the shape of the 'petal' for the dissipation curve

23.04.2018 | Physics and Astronomy

Clean and Efficient – Fraunhofer ISE Presents Hydrogen Technologies at the HANNOVER MESSE 2018

23.04.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>