Do plants respond to low frequency electromagnetic waves?

[Aidyan]

I'm wondering if plants are sensitive to electromagnetic (EM) waves? Of course I'm not speaking of light but in the low frequency domain, say from 0 Hz to 100 kHz? I looked up the web but couldn't find anything, only experiments with EM waves above the range of 300 Mhz. Has there been any research for lower frequencies? I'm asking just to be sure that sensitivity in this domain can be ruled out.

 

[jim mcnamara]

Generally papers that get published assert a positive effect. The reason for this is:
finding no effect, i.e., the NULL hypothesis is accepted. BUT. It is logically impossible to prove something does not exist/happen because you have to test every single possibility. In this case every species of plant.

Because of the internet fear mongering, some kinds of papers like what you need have been published. On different topics, however:

HAARP heats the ionosphere, aspartame is poisonous, flu vaccinations cause the disease, plants "like" classical music, etc.

I think you are reasonable to conclude there is no effect. Plus detecting wavelengths like you mention requires antennas of ridiculous expense and size for an ordinary lab to incur. So the practicality of testing is remote.

https://en.wikipedia.org/wiki/Extremely_low_frequency

Which also helps to explain why plants do not "see" the frequencies you are mentioning. Plus AFAIK, these frequencies are part of interstellar background "noise". So all living things have been exposed to it since day one. The atmosphere does not block incoming "noise" like that.

Pinging: @berkeman - who may be able to give more references.

 

[david_wechsler_stl]

Yes, plants are sensitive and responsive to EM fields in that range. I wrote a book on this topic a few years ago. Plants respond to static and dynamic electric fields across a huge range of voltages and frequencies. There is quite a bit of literature available, but you need to search around for it. Most papers show positive responses on the low-end of the spectrum, say, under 50 Hz... But as a field that has had on & off research over time, there is much to be learned.

Here is some selected research:
“Effects of Electrical and Electromagnetic Fields on Plants and Related Topics”, Andrew Goldsworthy, Book Chapter (Google Books link)

“http://www.researchgate.net/publication/237158211_Electrical_stimulation_and_its_effects_on_growth_and_ion_accumulation_in_tomato_plants“, Canadian Journal of Botany

Influence of pulsed electric field on growths of soil bacteria and pepper plant, Korean Journal of Chemical Engineering

Electrostimulation in Cell Biology by Low-Frequency Electromagnetic Fields, Electromagnetic Biology and Medicine

Hope this helps!
-David

 

[berkeman]

Yes, plants are sensitive and responsive to EM fields in that range. I wrote a book on this topic a few years ago. Plants respond to static and dynamic electric fields across a huge range of voltages and frequencies. There is quite a bit of literature available, but you need to search around for it. Most papers show positive responses on the low-end of the spectrum, say, under 50 Hz... But as a field that has had on & off research over time, there is much to be learned.

Here is some selected research:
“Effects of Electrical and Electromagnetic Fields on Plants and Related Topics”, Andrew Goldsworthy, Book Chapter (Google Books link)

“http://www.researchgate.net/publication/237158211_Electrical_stimulation_and_its_effects_on_growth_and_ion_accumulation_in_tomato_plants“, Canadian Journal of Botany

Influence of pulsed electric field on growths of soil bacteria and pepper plant, Korean Journal of Chemical Engineering

Electrostimulation in Cell Biology by Low-Frequency Electromagnetic Fields, Electromagnetic Biology and Medicine

Hope this helps!
-David

At least one of those references seem questionable, IMO. But assuming these are valid peer-reviewed references, can you please summarize the mechanism that is postulated for these interactions? Thanks.

The first reference seems to refer to attaching electrodes to the plant:

>The natural endogenous current in the plant

but the others imply that they are using electric fields, not direct contact. Can you say what physical mechanism they are suggesting causes these changes? Thanks.

 

[david_wechsler_stl]

Sure, from my understanding, the underlying mechanism is the Hodgkin-Huxley model (https://en.wikipedia.org/wiki/Hodgkin–Huxley_model) that describes the generation of action potentials from changing electric field concentrations with respect to the outside of the cell wall.

 

[Dale]

Sure, from my understanding, the underlying mechanism is the Hodgkin-Huxley model (https://en.wikipedia.org/wiki/Hodgkin–Huxley_model) that describes the generation of action potentials from changing electric field concentrations with respect to the outside of the cell wall.

That doesn’t make sense to me. Plants don’t generate action potentials. They do have transmembrane potentials (mostly based on H+ instead of Na+) but they don’t generate action potentials with them as far as I know. It is not immediately apparent to me how the Hodgkin-Huxley model is relevant.

 

[Dale]

Influence of pulsed electric field on growths of soil bacteria and pepper plant, Korean Journal of Chemical Engineering

The other two journals seem to be very low quality (impact factors 1.2 and 1.5 respectively). This one is a little better (impact factor 2.4). Note that it discusses electrodes directly placed in the soil, not EM waves. I don’t know if the OP is specifically interested in EM waves or any EM.

In this article the fields seemed to inhibit growth of a disease microorganism. So the positive response of the plant seemed to be due to the microorganism’s sensitivity rather than the plant. It definitely did not claim any action potentials.

 

[Torbert]

I grew 'Dwarf Danish Flag' bread seed poppies indoors under controlled conditions for three years. Four plants at a time, two growing through 8" ring magnets, pull force 105#, and two growing without magnets. Six generations later the records were compared and the results showed fruit weight and counts within the margin of error. Rates of growth were also the same.
A shorter one year test was done on another species of herb plant with the same results.

This is a 0 Hz field on two species out a million or so available. Hz>0 is beyond my means.
Amateur effort but I also have a curiosity about this subject.

 

[TeethWhitener]

The other two journals seem to be very low quality (impact factors 1.2 and 1.5 respectively). This one is a little better (impact factor 2.4).

I don’t love this method of evaluating suitability for PF. As an example from my own field, Solid State Communications and Physica B (both very well-known and well-regarded journals) have impact factors less than 2. Phys Rev A has an impact factor of 2.4 (edit: 2.9 in 2018). In addition, it’s quite difficult to compare impact factors across disciplines. In my own field (nanoscience), impact factors tend to be pretty high because there is a lot of publishing going on. I can easily imagine that a field like botany can have inherently lower impact factors.

 

[jim mcnamara]

We used Beall's list until fringe/vanity publishers threatened to sue the the compiler of the list.
https://en.wikipedia.org/wiki/Beall's_List - gone bye bye.

@TeethWhitener, yup, you are correct, for this type of Biology question that parameter is weak.

Give us a solution for fringe/woo stuff like this thread's original question. Please. We do not debunk, it is a waste of electrons.

 

[TeethWhitener]

Give us a solution for fringe/woo stuff like this thread's original question. Please. We do not debunk, it is a waste of electrons.

I understand. There's probably no easy solution, but FWIW I think the best course of action is to keep the thread narrowly focused around the peer-reviewed references that are brought up. After all, OP has a perfectly valid scientific question, even if questions like it attract cranks.

More on-topic: I'll point out that the references in post #3 from Can. J. Botany and Korean J. Chem. Eng. both pertain to DC electric fields. (If you crank the voltage up high enough, I bet you'll get a response from just about any living thing.) The Can. J. Botany reference in particular specifically states that the observed ion accumulation under the field is not merely passive. There's a review from 1984 that cites that paper which might be of use to OP:
https://link.springer.com/article/10.1007/BF02861092

Apparently this topic sees some interest in agricultural applications for non-chemical weed control. The principal lethal effect seems to come from heating due to ionic motion.

 

[Dale]

I don’t love this method of evaluating suitability for PF

I think the best course of action is to keep the thread narrowly focused around the peer-reviewed references that are brought up

Unfortunately, with the proliferation of predatory journals "peer-reviewed" is not a good indicator of reference credibility either. I do recognize the limitations of impact factors, but given the absence of a good source like Jeff Beall's list I think that impact factors are the best "first-pass" credibility criterion.

Of course, there is no hard and fast rule here, and PF does not have an impact factor threshold. But if the impact factor is low then that does require some justification. If a particular field generally has low impact factors, then that is a potential justification that should be considered, and it could be addressed by comparison with the top few journals. A low impact factor is in fact good information indicating low credibility, it is not conclusive by itself but it is definitely informative.