Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pesticide resistance warning after gene discovery

27.09.2002


Scientists have raised concerns following the discovery of a single gene that gives vinegar flies resistance to a wide range of pesticides, including the banned DDT.

Scientists are worried as this single mutation unexpectedly provides the fly (Drosophila melanogaster) with resistance to a range of commonly available, but chemically unrelated, pesticides. Significant also, is this species is rarely targeted with pesticides and many of the chemicals it is resistant to, it has never been exposed to before.

Researchers at the University of Melbourne and the Centre for Environmental Stress and Adaptation Research (CESAR) that made the discovery believe the mutation arose in Drosophila soon after the introduction of DDT and has since spread throughout the world. The gene has also persisted rather than, as expected, disappearing as the use of DDT around the world declined.



"This is a warning that we may need to rethink our overall strategies to control insect pests," says University of Melbourne geneticist, Dr Phil Batterham, and Program Leader for the Chemical Stress Program within CESAR, a special research centre that includes researchers from the Universities of Melbourne, La Trobe and Monash.

"The fact that a single mutation can confer resistance to DDT and a range of unrelated pesticides, even to those the species has never encountered, reveals new risks and costs to the chemical control of pest insects. Unless we reassess our current methods of pest management, our future options for control may become severely restricted," he says.

"If this mutation was found on a pest insect, many options for the chemical control of that insect would have been removed."

The research is published in the latest edition of the prestigious journal Science.

Batterham suggests that it is now imperative that research and industry focus on refining integrated pest management, which incorporates a broad arsenal of pest control measures including biological control and crop management techniques.

The Drosophila resistance gene, named Cyp6g1, is part of a large family of genes called the Cytochrome P450 genes that are found in many species, including humans.

Previous studies have implicated some members of this P450 family in pesticide resistance. However the function of the majority of the 90 Drosophila P450 genes is unknown.

CESAR is now analysing these genes to determine their function in Drosophila and in the pest insects, the cotton bollworm (Helicoverpa armigera) and the sheep blowfly responsible for flystrike (Lucilia cuprina).

"Our capacity to control pests would be significantly improved if we understood the defence mechanisms controlled by these genes," says Batterham.

In the Drosophila, Cyp6g1 confers resistance by producing up to 100 times more than the normal level of protein that breaks down DDT and other pesticides. Given the number of P450 genes present in Drosophila, it was unexpected that a single version of one gene could be associated with such widespread resistance, and that this resistance also applied to a wide range of compounds that bear no resemblance to each other in structure or mode of function. These compounds include organochlorines, organophosphorous, carbamate and insect growth regulator insecticides.

"Our research, so far, does not unequivocally demonstrate that Cyp6g1 is the sole culprit for this resistance, but the current evidence leaves little doubt that about its central role," says Batterham.

Species will normally lose mutations that protected it against a particular pesticide once that pesticide ceases to be used. This is because, in the absence of the pesticide, the mutation suddenly confers a disadvantage. In this case, the Drosophila has maintained the resistance gene and is still ’fit’. That is, the mutation does not confer any disadvantage, so it persists in the population.

"This highlights more than ever that what we do today to control pests could irreversibly change the gene pool of that species," says Batterham.

"Researchers investigating pesticide resistance sometimes fails to take sufficient notice of research into Drosophila. It maybe a model genetic organism, but it is still an insect and things that happen to Drosophila happen to other insects," he warns.

"This research showed how easy it is for a single mutation to have such a diverse impact. A similar mutation in a pest species could have devastating consequences" he says.

The primary research was done by Dr. Phil Daborn (a former PhD student under Dr Batterham and Professor John McKenzie at the University of Melbourne) in the laboratory of Professor Richard ffrench-Constant at the University of Bath and current University of Melbourne students, Michael Bogwitz and Trent Perry, supervised by Dr. Batterham and Dr. David Heckel. Other collaborators include Professor Tom Wilson at Colorado State University and Dr. Rene Feyereisen at INRA (Centre de Recherches d’Antibes, France).

Jason Major | EurekAlert!
Further information:
http://www.unimelb.edu.au/

More articles from Agricultural and Forestry Science:

nachricht New gene for atrazine resistance identified in waterhemp
24.02.2017 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

nachricht Researchers discover a new link to fight billion-dollar threat to soybean production
14.02.2017 | University of Missouri-Columbia

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>