Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using Mother Nature to provide an environmentally friendly method for reducing mosquitoes

21.07.2010
New research at the University of Haifa has made a breakthrough in identifying chemical substances released by mosquitoes' natural predators that function as warning signals for egg laying mosquitoes.

A scientific breakthrough might assist in the fight against mosquitoes. New research carried out at the University of Haifa in collaboration with researchers from other universities has chemically identified, for the first time, compounds released by mosquitoes' natural aquatic predators that function as warning signals for egg laying mosquitoes. Introducing these natural chemicals into mosquito breeding sites will cause the mosquitoes to sense risk of predation to their progeny and avoid laying their eggs there. These findings will soon be published in the prestigious journal Ecology Letters.

Ecologists and evolutionary biologists have known for a long time that many prey species can detect predators chemically and, upon detection, take various actions to avoid being eaten or avoid having their progeny eaten. Yet, the chemical identity of the predator-released chemicals has remained elusive. Knowing the chemical identity of these compounds would greatly facilitate scientists’ understanding of predator-prey relationships and the importance of these compounds in affecting ecological communities. They may also provide an eco-friendly alternative for mosquito control.

The new breakthrough research, funded by the Israel Science Foundation, was developed in Prof. Leon Blaustein's laboratory at the University of Haifa. Prof. Blaustein’s research partners comprised a multi-disciplinary group: Alon Silberbush, a doctoral student, Dr. Shai Markman, a chemical ecologist from University of Haifa-Oranim, Dr. Efraim Lewinsohn and Einat Bar, chemists at the Newe Yaar Research Center, and Prof. Joel E. Cohen, a mathematical and population biologist at Rockefeller and Columbia Universities.

Previous research from Blaustein’s lab demonstrated that the mosquito, Culiseta longiareolata, chemically detects a voracious predator of its progeny in the water, the backswimmer, Notonecta maculata, and avoids laying eggs where the predator is detected. However, until recently, the chemical identity of these predator-released compounds was not known. By screening and comparing the chemicals released by N. maculata with those released by Anax imperator, another aquatic predator that does not elicit a chemical response by the mosquito, they were able to narrow down the potential chemicals that elicited the mosquito’s behavioral response. Blaustein’s group then conducted outdoor experiments on potential chemicals and determined that two of these N. maculata-released chemicals, n-tricosane and n-heneicosane, repelled these mosquitoes from laying eggs. The two compounds together had an additive effect.

Applying such synthetic compounds to mosquito breeding sites would not only result in much fewer mosquitoes in the immediate area but probably reduce mosquito populations overall. Increased searching by pregnant mosquitoes for a breeding site that is perceived as predator-free increases greatly the probability of dying before egg laying; mosquitoes, on average, incur a 20 percent probability of mortality per day. Moreover, mosquitoes, by concentrating their eggs in considerably fewer breeding sites perceived as predation-risk free, would increase competition among the mosquito larvae resulting in fewer and weaker emerging adults.

Prof. Blaustein explains that in the fight against mosquitoes, there are essentially three lines of defense. The first and preferred line of defense is to prevent emergence of adult mosquitoes from aquatic breeding sites. When this has not been done effectively, mosquito control workers resort to trying to kill the adults that have spread to residential areas. This is much more difficult, more expensive, and usually involves chemical pesticides of environmental and health concerns. When these two lines of defense fail, the burden falls on the public to prevent mosquitoes in search of a blood meal from biting them, such as staying indoors and using mosquito repellents applied to the human skin. Prof. Blaustein points out that options for all three lines of defense are often chemicals that negatively affect the environment and are of health concerns to humans. Moreover, mosquitoes often develop resistance to chemical pesticides so there is always a need to find new weapons against mosquitoes. A bacterial pesticide, Bacillus thuringiensis israeIensis, can be very effective in killing mosquito larvae in breeding habitats while having relatively minor non-target effects, but it is rather expensive and is not effective in highly organic-polluted water.

This research group’s new findings of chemical identification of predator-released egg-laying repellants can be a breakthrough in providing a natural, environmentally friendly and inexpensive option to the arsenal in the first line of defense.

Blaustein adds, “While we see this as a potentially large breakthrough in developing another weapon against mosquitoes, the work, is not over. We hope this breakthrough will spur further research to chemically determine other effective predator-released chemicals, particularly ones that are long lasting and then tested for their efficacy.”

For more details contact Rachel Feldman • Tel: +972-4-8288722

Rachel Feldman | University of Haifa
Further information:
http://www.haifa.ac.il

More articles from Life Sciences:

nachricht Staying in Shape
16.08.2018 | Max-Planck-Institut für molekulare Zellbiologie und Genetik

nachricht Chips, light and coding moves the front line in beating bacteria
16.08.2018 | Okinawa Institute of Science and Technology (OIST) Graduate University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Staying in Shape

16.08.2018 | Life Sciences

Diving robots find Antarctic seas exhale surprising amounts of carbon dioxide in winter

16.08.2018 | Earth Sciences

Protein droplets keep neurons at the ready and immune system in balance

16.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>