Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sex-pheromone link to insect evolution

11.09.2002


Cornell University entomologists have unlocked an evolutionary secret to how insects evolve into new species. The discovery has major implications for the control of insect populations through disruption of mating, suggesting that over time current eradication methods could become ineffective, similar to the way insects develop pesticide resistance.



The researchers, led by Wendell L. Roelofs, the Liberty Hyde Bailey Professor of Insect Biochemistry at Cornell, made the discovery while examining ways to keep European corn borers from mating, multiplying and then chewing up farmers’ fields. They discovered the existence of a previously undetected gene, the delta-14, that can regulate the attractant chemicals produced in sex-pheromone glands of female borers. The gene can be suddenly switched on, changing the pheromone components that females use to attract males for mating.

The entomologists have demonstrated that insects evolve chemical systems in leaps rather than in minute stages, as had been previously assumed. The researchers also discovered that there are rare males in the corn borer population -- about 1 in 200 -- capable of responding to chemicals produced by the delta-14 gene.


"This is one way that insects become new species," says Roelofs, whose paper, "Evolution of moth sex pheromones via ancestral genes," will be published on the web site of the Proceedings of the National Academy of Science (Sept. 9-15, 2002.) The Cornell co-authors on the paper are: Weitian Liu, research associate in entomology; Guixia Hao, postdoctoral researcher in entomology; Hongmei Jiao, laboratory technician in entomology; and Charles E. Linn Jr., senior research associate in entomology. Alejandro P. Rooney, Mississippi State University assistant professor in biological sciences also contributed to the paper. The research was funded by the National Science Foundation and will continue to be funded by the U.S. Department of Agriculture’s National Research Initiative.Roelofs explains that female insects attract males with specialized pheromones that he compares to radio frequencies. At major events with thousands of people, for instance, police might communicate on channel one, emergency medical personnel on channel two and administrators on channel three.

"With male and female borers, it’s the same thing," says Roelofs. "Certain species communicate on channel one, others on channel two, others on channel three. But when a female has a mutated delta-14 gene -- and by mutated I mean the gene is turned on -- it changes her channel from three to five. That means that out of 200 male borers, 199 cannot respond to her. It’s the one male borer capable of responding to her very selective channel that sets out to mate."

Soon other females with the delta-14 gene mate with other rare respondent males. Eventually, over time, the males and females stabilize their pheromone communication system, essentially isolating this new population from the parent species. "That’s one way species evolve," Roelofs says.

Manipulation of insect chemistry is an effective pest control strategy in that it can be used to disrupt mating behavior. For more than 20 years, Roelofs’ research at Cornell’s New York State Agricultural Experiment Station in Geneva has focused on chemical analyses of the pheromone components. Agricultural researchers have identified pheromones in over 1,000 species of insects and use them to monitor pest populations in 250 species and to disrupt mating in more than 20 species, Roelofs says.

This new research has implications for pest control. In addition to explaining how pheromone evolution might have occurred in the past, the paper also demonstrates that the conditions required for dramatic shifts in pheromone blends could well be present today and in the future. Insect populations could be capable of shifting away from a pheromone blend being used for their control in the field, making such control ineffective.

"Based on the difficulty of generating even small changes in pheromone blends in the lab, we thought that such resistance could not develop because natural pressure would prevent the species from gradually shifting to a different blend," says Roelofs. The presence of this kind of gene, capable of sudden activation, might provide a mechanism for resistance to occur, although no evidence for this has been found so far, he notes.

Roelofs expects this discovery to stimulate more research in this area, specifically to determine the breadth of the phenomenon and how it affects the evolution of many insect communication systems. His research team will be working on the genomes of fruit flies, mosquitoes, crickets and silkworms to detect if these kinds of genes are present.

Blaine P. Friedlander, Jr. | Cornell University News Service

More articles from Life Sciences:

nachricht Protein Structure Could Unlock New Treatments for Cystic Fibrosis
14.12.2017 | Universität Zürich

nachricht Closing in on advanced prostate cancer
13.12.2017 | Institute for Research in Biomedicine (IRB Barcelona)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

A whole-body approach to understanding chemosensory cells

13.12.2017 | Health and Medicine

Water without windows: Capturing water vapor inside an electron microscope

13.12.2017 | Physics and Astronomy

Cellular Self-Digestion Process Triggers Autoimmune Disease

13.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>