Venus flytraps found to produce magnetic fields

February 02, 2021

The Venus flytrap (Dionaea muscipula) is a carnivorous plant that encloses its prey using modified leaves as a trap. During this process, electrical signals known as action potentials trigger the closure of the leaf lobes. An interdisciplinary team of scientists has now shown that these electrical signals generate measurable magnetic fields. Using atomic magnetometers, it proved possible to record this biomagnetism. "You could say the investigation is a little like performing an MRI scan in humans," said physicist Anne Fabricant. "The problem is that the magnetic signals in plants are very weak, which explains why it was extremely difficult to measure them with the help of older technologies."

Electrical activity in the Venus flytrap is associated with magnetic signals

We know that in the human brain voltage changes in certain regions result from concerted electrical activity that travels through nerve cells in the form of action potentials. Techniques such as electroencephalography (EEG), magnetoencephalography (MEG), and magnetic resonance imaging (MRI) can be used to record these activities and noninvasively diagnose disorders. When plants are stimulated, they also generate electrical signals, which can travel through a cellular network analogous to the human and animal nervous system.

An interdisciplinary team of researchers from Johannes Gutenberg University Mainz (JGU), the Helmholtz Institute Mainz (HIM), the Biocenter of Julius-Maximilians-Universität of Würzburg (JMU), and the Physikalisch-Technische Bundesanstalt (PTB) in Berlin, Germany's national meteorology institute, has now demonstrated that electrical activity in the Venus flytrap is also associated with magnetic signals. "We have been able to demonstrate that action potentials in a multicellular plant system produce measurable magnetic fields, something that had never been confirmed before," said Anne Fabricant, a doctoral candidate in Professor Dmitry Budker's research group at JGU and HIM.

The trap of Dionaea muscipula consists of bilobed trapping leaves with sensitive hairs, which, when touched, trigger an action potential that travels through the whole trap. After two successive stimuli, the trap closes and any potential insect prey is locked inside and subsequently digested. Interestingly, the trap is electrically excitable in a variety of ways: in addition to mechanical influences such as touch or injury, osmotic energy, for example salt-water loads, and thermal energy in the form of heat or cold can also trigger action potentials. For their study, the research team used heat stimulation to induce action potentials, thereby eliminating potentially disturbing factors such as mechanical background noise in their magnetic measurements.

Biomagnetism - detection of magnetic signals from living organisms

While biomagnetism has been relatively well-researched in humans and animals, so far very little equivalent research has been done in the plant kingdom, using only superconducting-quantum-interference-device (SQUID) magnetometers, bulky instruments which must be cooled to cryogenic temperatures. For the current experiment, the research team used atomic magnetometers to measure the magnetic signals of the Venus flytrap. The sensor is a glass cell filled with a vapor of alkali atoms, which react to small changes in the local magnetic-field environment. These optically pumped magnetometers are more attractive for biological applications because they do not require cryogenic cooling and can also be miniaturized.

The researchers detected magnetic signals with an amplitude of up to 0.5 picotesla from the Venus flytrap, which is millions of times weaker than the Earth's magnetic field. "The signal magnitude recorded is similar to what is observed during surface measurements of nerve impulses in animals," explained Anne Fabricant. The JGU physicists aim to measure even smaller signals from other plant species. In the future, such noninvasive technologies could potentially be used in agriculture for crop-plant diagnostics, by detecting electromagnetic responses to sudden temperature changes, pests, or chemical influences without having to damage the plants using electrodes.
The results of the study have been published in Scientific Reports. The project received financial support from the German Research Foundation (DFG), the Carl Zeiss Foundation, and the German Federal Ministry of Education and Research (BMBF).

Related links: - Budker Group at JGU and HIM ; - Helmholtz Institute Mainz ; - Hedrich Group on Molecular Plant Physiology and Biophysics at Julius-Maximilians-Universität of Würzburg ; - Metrology of Ultra-Low Magnetic Fields core facility at PTB

Read more: - press release "Danila Barskiy receives Sofja Kovalevskaja Award to develop low-cost portable spectroscopic devices" (22 Sept. 2020) ; - press release "New NMR method enables monitoring of chemical reactions in metal containers" (15 July 2020) ; - press release "New simple method for measuring the state of lithium-ion batteries" (7 May 2020) ; - press release "ERC Advanced Grant for experimental physicist Dmitry Budker" (12 May 2016)

Johannes Gutenberg Universitaet Mainz

Related Electrical Activity Articles from Brightsurf:

Knotting semimetals in topological electrical circuits
Scientists created exotic states of matter using electrical circuit enhanced by machine-learning algorithm

Physicists make electrical nanolasers even smaller
Researchers cleared the obstacle that had prevented the creation of electrically driven nanolasers for integrated circuits.

Using tiny electrodes to measure electrical activity in bacteria
Scientists at Laboratory of Organic Electronics, Linköping University, have developed an organic electrochemical transistor that they can use to measure and study in fine detail a phenomenon known as extracellular electron transfer in which bacteria release electrons.

Using electrical stimulus to regulate genes
A team of researchers led by ETH professor Martin Fussenegger has succeeded in using an electric current to directly control gene expression for the first time.

Like a molecular knob: That is how a gene controls the electrical activity of the brain
Its name is Foxg1, it is a gene, and its unprecedented role is the protagonist of the discovery just published on the journal Cerebral Cortex.

Electrical activity in living organisms mirrors electrical fields in atmosphere
A new Tel Aviv University study provides evidence for a direct link between electrical fields in the atmosphere and those found in living organisms, including humans.

3D-printed plastics with high performance electrical circuits
Rutgers engineers have embedded high performance electrical circuits inside 3D-printed plastics, which could lead to smaller and versatile drones and better-performing small satellites, biomedical implants and smart structures.

In and out with 10-minute electrical vehicle recharge
Electric vehicle owners may soon be able to pull into a fueling station, plug their car in, go to the restroom, get a cup of coffee and in 10 minutes, drive out with a fully charged battery, according to a team of engineers.

Electrical stimulation aids in spinal fusion
Spine surgeons in the U.S. perform more than 400,000 spinal fusions each year as a way to ease back pain and prevent vertebrae in the spine from wiggling around and doing more damage.

The effectiveness of electrical stimulation in producing spinal fusion
Researchers from The Johns Hopkins University School of Medicine performed a systematic review and meta-analysis of published data on the effect of electrical stimulation therapies on spinal fusion.

Read More: Electrical Activity News and Electrical Activity Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to