Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New 'green' pesticides are first to exploit plant defenses in battle of the fungi

24.03.2009
Exploiting a little-known punch/counterpunch strategy in the ongoing battle between disease-causing fungi and crop plants, scientists in Canada are reporting development of a new class of "green" fungicides that could provide a safer, more environmentally-friendly alternative to conventional fungicides.

They will report on the first pesticides to capitalize on this unique defensive strategy here today at the 237th National Meeting of the American Chemical Society.

Developed with sustainable agriculture in mind, the new fungicides — called "paldoxins" — could still do the work of conventional pesticides, helping to protect corn, wheat and other crops. These crops increasingly are used not just for food, but to make biofuels. The new fungicides also could help fight the growing problem of resistance, in which plant pests shrug off fungicides, the researchers suggest.

Most fungicides today are made based on chemicals that can kill potentially beneficial organisms and have other adverse environmental effects. The new materials are more selective, stopping fungi that cause plant diseases without harming other organisms. They work in a unique way, disrupting a key chemical signalling pathway that the fungi use to breakdown a plant's normal defenses. As a result, the plants boost their natural defenses and overcome fungal attack without harming people and the environment, the researchers say.

"Conventional fungicides kill constantly," explains study leader Soledade Pedras, Ph.D., a professor of chemistry at the University of Saskatchewan in Canada. "Our products only attack the fungus when it's misbehaving or attacking the plant. And for that reason, they're much safer."

Researchers have known for years that many plants have a defense mechanism that involves production of natural chemicals, called phytoalexins, to kill disease-causing fungi. The fungus, however, fights back. It releases enzymes that detoxify, or destroy, the phytoalexin, leaving the plant vulnerable to the fungi's attack.

To take advantage of that punch-counterpunch strategy, Pedras and her colleagues proposed the development of new anti-fungal agents to block the fungi's destruction of phytoalexins. They termed these new agents paldoxins, short for phytoalexin detoxification inhibitors.

Pedras discovered those agents after screening broccoli, cauliflower, mustard greens and other plants in the so-called "crucifer family." They discovered the most powerful phytoalexin in a flowering plant called camelina or "false flax." In laboratory tests, camelina phytoalexins blocked detoxifying enzymes produced by a wide variety of fungi.

"We found that many fungi couldn't degrade this chemical," says Pedras. "So that's what we used to design synthetic versions that were even stronger than the original."

The researchers now have developed six different synthetic versions of the paldoxins, which are essentially potent inhibitors of fungal enzymes.

The researchers have successfully tested the synthetic paldoxins in the lab on several crucifer plants, including rapeseed plants and mustard greens. Pedras' group plan field tests of their new fungicides on other important crop varieties. In the future, a similar strategy will be applied to grasses such as wheat, rye, and oat. These grassy plants tend to be more difficult to protect with fungicides than broccoli and related veggies, the researchers say.

If studies continue to show promise, the paldoxins could be marketed quickly, within a few years, Pedras says. The new fungicides could be applied like conventional pesticides.

The Natural Sciences and Engineering Research Council of Canada and the University of Saskatchewan funded the study.

The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 154,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.

Michael Bernstein | EurekAlert!
Further information:
http://www.acs.org

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>