Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Aphids make ‘chemical weapons’ to fight off killer ladybirds

11.07.2007
Cabbage aphids have developed an internal chemical defence system which enables them to disable attacking predators by setting off a mustard oil ‘bomb’, says new research published today.

The study shows for the first time how aphids use a chemical found in the plants they eat to emit a deadly burst of mustard oil when they’re attacked by a predator, for example a ladybird. This mustard oil kills, injures or repels the ladybird, which then saves the colony of aphids from attack, although the individual aphid involved usually dies in the process.

When the aphids feed on cabbages, they consume chemicals called glucosinolates which are found in the nutrient transport vessels of the plant. Once eaten, these chemicals are then stored in the aphids’ blood. Mimicking the plants themselves, the aphids also produce an enzyme called myrosinase, which is stored in the muscles of their head and thorax. In the event of a predator attack this enzyme in the muscles comes into contact with the glucosinolates in the blood, catalysing a violent chemical reaction which releases mustard oil.

The research team from the UK and Norway confirmed their findings by controlling the diet of different groups of aphids. They found that those insects eating a diet rich in glucosinolates had a high success rate in fending off predators, whereas those without glucosinolates in their diet did not. Scientists already knew that aphids absorbed these chemicals from their food, but this study published Proceedings of the Royal Society B is the first of its kind to prove that they form the basis of a chemical defence system.

The scientists also found that the extent to which glucosinolates are stored up by the aphids from birth into adulthood depends on whether or not they develop wings. Those aphids that grow wings see a rapid decline in the amount of glucosinolates they store from the time wing buds start to develop.

Dr Glen Powell from Imperial College London’s Division of Biology, one of the paper’s authors, explains: “Our study seems to show that aphids that develop wings cease to store this chemical in their blood as they mature, as they don’t need the ‘mustard oil bomb’ to defend themselves from predators when they can just fly away. This is a great example of the way in which a species provides an ingenious method of protecting itself, whatever the circumstances.”

Dr Powell adds: “In the wild, aphids live in clonal colonies, with often many hundreds of individuals crowded together on a plant, and using this poisonous mustard oil defence provides wingless individuals with a powerful means of dispelling a predator which poses a risk to the entire colony. Unfortunately the nature of the mechanism – with the chemical stored in the insect’s blood and the catalyst stored in its muscles – means that in most cases the individual aphid responsible for seeing-off the ladybird predator dies in the process of protecting the colony.”

Danielle Reeves | alfa
Further information:
http://www.imperial.ac.uk

More articles from Ecology, The Environment and Conservation:

nachricht Value from wastewater
16.08.2017 | Hochschule Landshut

nachricht Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Gold shines through properties of nano biosensors

17.08.2017 | Physics and Astronomy

Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter

17.08.2017 | Earth Sciences

Mars 2020 mission to use smart methods to seek signs of past life

17.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>