Featured Research

from universities, journals, and other organizations

Deceitful lily fools flies: Solomon's lily imitates a yeasty odor to lure vinegar flies into a trap

Date:
October 10, 2010
Source:
Max Planck Institute for Chemical Ecology
Summary:
Scientists in Germany have solved a case of fraud that has been pending for 40 million years. Arum palaestinum, called the Solomon's lily, attracts vinegar flies as pollinators by emitting odor molecules that resemble those produced during alcoholic fermentation of rotting fruit initiated by yeast. The plant accomplishes the illusion of yeast by producing specific chemicals that create the impression of fermentation in the fly brain.

These are vinegar flies trapped in the calyx of the lily Arum palaestinum.
Credit: Johannes Stökl, Curr. Biol., Oct. 7, 2010

Scientists from the Max Planck Institute for Chemical Ecology in Jena, Germany, have solved a case of fraud that has been pending for 40 million years.

Related Articles


Arum palaestinum, also called the Solomon's lily, attracts drosophilids (vinegar flies) as pollinators by emitting odor molecules that resemble those produced during alcoholic fermentation of rotting fruit initiated by yeast. The plant accomplishes the illusion of yeast simply by producing six chemicals that -- together in a specific mix -- create the impression of fermentation in the fly brain. The produced volatiles include two chemicals which are very rarely encountered in plants but are typical of wine and vinegar -- actually byproducts of yeast activity. The scientists showed that the lily's fragrance targets a deeply conserved neuronal pathway specifically tuned to yeast odors. Thus, the Solomon's Lily is exploiting a million-year-old instinct in flies for its own purposes.

The research is published in the journal Current Biology.

Fly-napping plants

The genus Drosophila -- vinegar flies -- consists of many species that feed on a variety of sources ranging from fruit to bacterial layers on certain tropical land crab species. For most drosophilids, yeast is the main food. Their antennae and antennal lobes, the first brain region that receives input from the olfactory sensory neurons, are accordingly specialized in perceiving odor molecules typically emitted by growing yeast. The smallest concentrations are sufficient to lead vinegar flies to their food source.

Many flowering plants depend on insect pollinators; they ensure that offspring are produced and guarantee genetic variability. Flowers use colorful petals and odor bouquets to attract them. Although often pollination service is rewarded with sweet nectar, Arum palaestinum tricks its pollinators. The plant, also called the Solomon's Lily, produces an odor in its violet-black flowers that to a human nose is most similar to a fruity wine. It was obvious that the plant attracts pollinators with this odor, namely vinegar flies. But unlike other flowers, Arum palaestinum does not give a reward in form of nectar; in fact, flies are trapped in the flower overnight and not released until the next day.

Drosophila melanogaster is also deceived

Johannes Stökl and Marcus Stensmyr have not only collected and analyzed this odor, but also examined and identified the drosophilid species trapped in the plant. Together with behavioral biologist Markus Knaden, they studied the reactions of the insects to different odor molecules. In addition, their colleagues Silke Sachse and Antonia Strutz performed neurophysiological measurements on the flies. The studies provided interesting results: Arum palaestinum attracts an average of 140 flies per plant, mainly flies from eight different Drosophila species including the well-known laboratory work horse and kitchen nuisance Drosophila melanogaster. Fourteen chemical compounds that caused the flies' antennae to respond were emitted by the plant. To test these reactions, Johannes Stökl measured and recorded the action potentials in the antennae of the insects. Chemical analysis of the odor compounds released by the plants showed that most were esters.

"The most remarkable odors of the bouquet were 2,3-butandiol acetate and acetoin acetate," explains Marcus Stensmyr, leader of the study. Interestingly, these molecules are not contained in the bouquets of flowering plants, but are characteristic of vinegar, especially aceto balsamico, and wine -- or, in other words: yeast fermentation products. Those two compounds as well as four more that also emerge during yeast fermentation showed the strongest and most stable signals in the electroantennograms.

Two receptors, one fraud

In neurophysiological experiments, the flies were exposed to natural odor bouquets, such as the smells of rotting peaches or bananas as well as Lambrusco (red wine) and aceto balsamico (vinegar). The respective electroantennograms strikingly resembled the recordings from flies that had been exposed to the lily odor, suggesting that to a fly, these odors have a most similar smell.

"The flies are unable to distinguish the lily from rotting fruit -- they are deceived by the lily because it imitates the yeasty odor although it does not offer yeast as food," says Johannes Stökl. The insects' involuntary pollination service is not even rewarded; in fact, just the opposite is true: the flies are trapped in the flower until it opens again after 24 hours -- and they stay hungry.

Using transgenic flies expressing a calcium sensitive activity reporter, Silke Sachse, leader of the Functional Imaging Group, and her PhD student Antonia Strutz, were able to trace the activity of the yeast odor stimulants in the brains of the flies. This functional imaging technology helped to demonstrate that eleven different odorant receptors were activated. Because different drosophilid species were deceived by the Solomon's Lily, it seemed likely that evolutionary ancient odorant receptors were among the activated ones, and this turned out to be the case. "The sequence of two of the odorant receptors, namely Or42b and Or92a, is highly conserved. These genes are likely to have a critical function as "yeast detectors" across most, if not all drosophilid flies," explains Bill Hansson, director at the institute.

Is keeping a Solomon's lily now the ultimate solution to rid your kitchen of flies? "Well, since they only flower once per year, and then only for a few hours, a cup of vinegar is still a better option. However, during the hours it flowers, I can assure you there will be no flies left in your kitchen!" says Marcus Stensmyr.


Story Source:

The above story is based on materials provided by Max Planck Institute for Chemical Ecology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Johannes Stökl, Antonia Strutz, Amots Dafni, Ales Svatos, Jan Doubsky, Markus Knaden, Silke Sachse, Bill S. Hansson, Marcus C. Stensmyr. A deceptive pollination system targeting drosophilids through olfactory mimicry of yeast. Current Biology, 2010; DOI: 10.1016/j.cub.2010.09.033

Cite This Page:

Max Planck Institute for Chemical Ecology. "Deceitful lily fools flies: Solomon's lily imitates a yeasty odor to lure vinegar flies into a trap." ScienceDaily. ScienceDaily, 10 October 2010. <www.sciencedaily.com/releases/2010/10/101007123109.htm>.
Max Planck Institute for Chemical Ecology. (2010, October 10). Deceitful lily fools flies: Solomon's lily imitates a yeasty odor to lure vinegar flies into a trap. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2010/10/101007123109.htm
Max Planck Institute for Chemical Ecology. "Deceitful lily fools flies: Solomon's lily imitates a yeasty odor to lure vinegar flies into a trap." ScienceDaily. www.sciencedaily.com/releases/2010/10/101007123109.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) — Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) — Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
New Fish Species Discovered, Setting Record for World's Deepest

New Fish Species Discovered, Setting Record for World's Deepest

Buzz60 (Dec. 22, 2014) — A new species of fish is discovered living five miles beneath the ocean surface, making it the deepest living fish on earth. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) — Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins