Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Plants can do maths

22.01.2016

The carnivorous Venus flytrap carefully plans its meals: It can count how often it is touched by an insect to calculate the digestive effort. This discovery has been made by plant scientists of the University of Würzburg.

Usually, plants are eaten by animals and humans. With carnivorous plants, however, it's the other way round: They have specialised in animals as an extra source of nutrition to help them survive in moors or other nutrient-poor sites.


Insect on a Venus flytrap – it has not snapped shut yet.

(Photo: Sönke Scherzer)

Take the Venus flytrap (Dionaea muscipula) for example: It has a trapping structure formed by the terminal portion of leaves and is triggered by tiny hairs on their inner surface. These sensors allow the plant to discover, catch and digest flies and other fast animals.

The trap's insides are covered by a turf of red glands. This flower-like appearance combined with fruity smells attracts many insects. Looking for nectar, the visitors inevitably touch the three sensor hairs located on each of the lobes. Based on the number of times the trigger hair is stimulated, the plant decides whether to snap the trap closed and start digestion. This means that the plant is capable of counting.

The discovery was made by an international team of researchers around biophysicist Professor Rainer Hedrich from the University of Würzburg. Their work has been published in the renowned journal Current Biology.

Trap closes on "two"

If a trigger hair on the Venus flytrap is stimulated only slightly, it will signal the first prey contact by transmitting a bio-electrical signal. "One signal does not yet cause a reaction – it could be false alarm after all," says Hedrich. But a second stimulation already causes the trap to snap close in the blink of an eye.

If the prey stayed calm now, there would be no other signal. In that case, the trap will open again after a half day. But since the trapped animals usually put up quite a fight, they trigger a virtual fireworks of signals sealing their fate for good.

This is because the Venus flytrap can count further, as Hedrich's colleague Sönke Scherzer found out. He measured that a trapped insect triggers some 60 signals per hour. To imitate the contact stimuli, Scherzer nudged individual sensory hairs up to 60 times in an hour to see what happened.

Digestive juices start to flow from "five"

The result: Two or more stimuli activate the pathway of the contact and wound hormone jasmonate JA. At five and more signals, the plant additionally activates the genes for digestions enzymes in all of its 37,000 glands. This activation does not take place if the jasmonate signal pathway is suppressed in experiments prior to mechanical stimulation. "We have thus proved that the electrical signal is converted into a hormone signal in the glands," Hedrich further.

Five or more signals also stimulate the transport molecules that provide for the absorption of the digested insects into the plant. While searching for this mechanism, one gene caught the attention of Würzburg Ph.D. student Jennifer Böhm. It is activated by both touching the sensory hairs and by the hormone jasmonate. She was able to demonstrate that it is an ion channel which transports sodium. Large quantities of this nutrient salt accrue when the insects are digested.

The plant can also do maths

"We asked ourselves whether the trap can calculate how many channels it must provide to remove the sodium," Hedrich explains. Obviously, the plant is able to do that: The bigger the prey animal, the more fiercely it will struggle and the more frequently the sensory hairs are stimulated. In that case, the Venus flytrap will produce more ion channels than for a weakly struggling animal.

And what about the plant's memory? According to Hedrich, the Venus flytrap can remember the number of prey contacts for at least four hours. Now the researchers want to study the molecular bases of retentivity and learn whether the sensory performance of plants and animals share similar underlying principles.

Funded by the European Research Council

Hedrich's exploration of the Venus flytrap and other carnivorous plants is backed by top-level funding: In 2010, the European Research Council (ERC) allocated him an "Advanced Grant" worth 2.5 million euros for this purpose. Within the scope of the ERC project "Carnivorom", Hedrich's team is on the lookout for those genes that make plants carnivorous.

„The Venus flytrap Dionaea muscipula counts prey-induced action potentials to induce sodium uptake“, Böhm, J., Scherzer, S., Krol, E., Kreuzer, I., von Meyer, K., Lorey, C., Mueller, T.D., Shabala, L., Monte, I., Solano, R., Al-Rasheid, K.A.S., Rennenberg, H., Shabala, S., Neher, E., Hedrich, R., Current Biology, January 21, 2015, DOI 10.1016/j.cub.2015.11.057

Contact

Prof. Dr. Rainer Hedrich, Department of Botany I of the University of Würzburg, Phone: +49 931 31-86100, hedrich@botanik.uni-wuerzburg.de


Robert Emmerich | Julius-Maximilians-Universität Würzburg
Further information:
http://www.uni-wuerzburg.de

Further reports about: ERC Julius-Maximilians-Universität genes insects jasmonate sensory hairs sodium

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton 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: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>