The discussion revolves around the feasibility of using low-frequency ultrasound (20-40 kHz) to penetrate through air and bone, and later, soil, for the purpose of stimulating plant growth without pesticides. Participants explore the technical challenges and potential applications of ultrasound in these contexts.
Participants express differing views on the effectiveness of ultrasound in penetrating materials and stimulating plant growth. There is no consensus on the feasibility of using ultrasound as a pesticide alternative or the specific parameters needed for successful application.
The discussion highlights uncertainties regarding the acoustic impedance of soil and the practical challenges of applying ultrasound in agricultural settings. Participants also note the need for further clarification on the experimental design and objectives.
Researchers and practitioners in botany, agriculture, and acoustics may find this discussion relevant, particularly those interested in innovative pest control methods and the application of ultrasound technology in plant growth stimulation.
thanks Baluncore for your answer, the main problem is the acoustic impedance, even at such low frequencies. what are ellipsoidal reflectors and transducer arrays anyway? can they penetrate solids with sufficient power?Baluncore said:Probably not.
The inverse square law, and several impedance mismatches, would greatly reduce the power density and scatter the energy. An interference pattern would be set up in the bone, so there would be no focussed beam.
Given enough power, anything is possible, but it will not remain a neat beam unless you start with a phased array transducer, or an ellipsoidal reflector to focus the energy.
An ellipse has two focal points. You put the transmitter at one focal point, with the bone target at the other. That overcomes the inverse square law and reflects most energy onto the bone.Sibilo said:... What are ellipsoidal reflectors and transducer arrays anyway?
yes Baluncore, then I need this project for a botany experiment and therefore the solid part is not the bone, but the soil. so if I used two 20 khz ultrasound beams how can the phase coupling overcome the limit, because if I'm not mistaken two 20 khz beams couple and generate an addition wave. Maybe I'm not understanding. basically I want the beam to overcome the solid barrier in this case the groundBaluncore said:An ellipse has two focal points. You put the transmitter at one focal point, with the bone target at the other. That overcomes the inverse square law and reflects most energy onto the bone.
A transducer array uses many emitters to produce waves, each with a phase that reinforces, where you want the energy to be concentrated.
That was a very skilful and fast moving of the goal posts.Sibilo said:yes Baluncore, then I need this project for a botany experiment and therefore the solid part is not the bone, but the soil.
yes baluncore I didn't understand what you mean by "very skilled movement" however the soil is quite dense, unfortunately in the translation the word "BONE" came out however the ultrasounds must reach the root and stimulate the plants that's all. except that impedance is a big problemBaluncore said:That was a very skilful and fast moving of the goal posts.
Overcoming the soil surface barrier is one problem.
It is unlikely the ultrasonic energy will remain well-behaved in a well-structured soil.
Back to the basics ... What must the beam do once it enters the soil?
no baluncore the dimensions of the roots obviously can vary they are not always fixed, furthermore I cannot put the transducer in the ground or near the plant because it would not make the plant grow and the grasses would destroy it. for the power now I need the beam to reach the root and go beyond the ground then later I can adjust it based on the growth of the plant. yes obviously I will do the experiments with small pots or in a greenhouse, but I have to overcome the problem of acoustic impedanceBaluncore said:What is the dimension of the roots that must be stimulated?
How much stimulation power do you require?
Why not bury ultrasound transducers among the roots?
Can you do the experiment in a specially shaped flower pot?
You ask a question, and I give you four more.
So you are not working on plants as big as trees in a forest.Sibilo said:no baluncore the dimensions of the roots obviously can vary they are not always fixed, ...
Are you trying to make plants grow differently, or to image something in the ground?Sibilo said:I cannot put the transducer in the ground or near the plant because it would not make the plant grow and the grasses would destroy it.
Acoustic impedance can be sorted once we know the shape and size of the plant problem. If the experiment can be done in a pot, then the pot can be shaped to focus the energy where it is needed.Sibilo said:... yes obviously I will do the experiments with small pots or in a greenhouse, but I have to overcome the problem of acoustic impedance ...
no for now I am focusing on small plants with roots that extend over a diameter of 3 or 4 cm, ultrasound is a way to grow plants without pesticides so that they develop their defenses independently. Unfortunately I'm only using the pot now but then I'll have to go to the greenhouse or open field. but if there is a way to overcome the impedance problem I will do my best to overcome itBaluncore said:So you are not working on plants as big as trees in a forest.
Are you trying to make plants grow differently, or to image something in the ground?
Are those plants grasses?
Acoustic impedance can be sorted once we know the shape and size of the plant problem. If the experiment can be done in a pot, then the pot can be shaped to focus the energy where it is needed.
What are you really trying to do?
Why do you need ultrasound in the soil?
I know that there are studies that show an increase growth rate with ultrasound (although it's usually in the lab setting, so in the real word it remains to be seen if it works the same), but I have not seen research that show pesticide can be effectively replaced with ultrasound. Do you have any reference for this?Sibilo said:ultrasound is a way to grow plants without pesticides so that they develop their defenses independently
Baluncore said:Now I need some time to think about the concept.
Will the frequency sweep or jump between 20 kHz and 40 kHz, or be fixed?
Will sound energy travel from above the plant or from the side?
Will short pulses of sound be sufficient to kill pests, or must it be continuous?
Do you have samples of pests that can be tested?
What are the feared pest species, stage, and size?
Will dogs, snakes and other animals hunt the source of o
no baluncore the frequency is always fixed, it does not change either in frequency or in amplitude. the beam will obviously be slightly above the plant a few cm. for animals like snakes there is no problem we have systems against them. furthermore, the parasites you mention are not small animals but in addition to those also bacteria and fungi that infect the plant, with ultrasound you could stimulate the defenses in a natural way. anyway, tell me how long it will take, and also if it were possible I would like to learn too
I attended a conference where this approach was discussed. however, by creecita we mean precisely that, that is, being able to keep the plant alive despite all the bacteria and viruses, it is still an experimental wayMotore said:I know that there are studies that show an increase growth rate with ultrasound (although it's usually in the lab setting, so in the real word it remains to be seen if it works the same), but I have not seen research that show pesticide can be effectively replaced with ultrasound. Do you have any reference for this?
I repeat the answer, then the frequency is fixed and also the amplitude, furthermore the beam travels slightly higher than the plant, as far as snakes or mice are concerned there are systems to chase them away. Furthermore, ultrasound is also used to eliminate bacteria and fungi. tell me how long it will take to get the answer because I want to learn tooBaluncore said:Now I need some time to think about the concept.
Will the frequency sweep or jump between 20 kHz and 40 kHz, or be fixed?
Will sound energy travel from above the plant or from the side?
Will short pulses of sound be sufficient to kill pests, or must it be continuous?
Do you have samples of pests that can be tested?
What are the feared pest species, stage, and size?
Will dogs, snakes and other animals hunt the source of ultrasound?
Can you give a link to the Conference Proceedings? Or was this more of an "Infomercial" type get-together...?Sibilo said:I attended a conference where this approach was discussed. however, by creecita we mean precisely that, that is, being able to keep the plant alive despite all the bacteria and viruses, it is still an experimental way
https://www.aduc.it/articolo/piante+hanno+linguaggio+base+ultrasuoni_30378.phpberkeman said:Can you give a link to the Conference Proceedings? Or was this more of an "Infomercial" type get-together...?
I studied the concept of acoustic impedance and I understood that it depends on the different density of the materials, so if the density is close the attenuation decreases so if we make the passage of the ultrasound in the air before the ground similar to the density of the ground?berkeman said:Can you give a link to the Conference Proceedings? Or was this more of an "Infomercial" type get-together...?
Yikes! That looks like nonsense from what little I've translated from Italian...Sibilo said:https://www.aduc.it/articolo/piante+hanno+linguaggio+base+ultrasuoni_30378.php
Ho berkerman this is a link, but tue conference was in my town
Plants have an ultrasound-based language
It was already known that plants had incredible senses for communicating with each other and with their environment. They are therefore equipped with photoreceptors to detect light and distinguish different colors in the spectrum of the same light. They are also equipped with the sense of touch: a tree will adapt its growth based on the wind and its intensity. They are also sensitive to smells and sounds. Plants have even been discovered that fluoresce when attacked by a caterpillar! But until now it was thought that plants remained silent beings.
Mistake! Plants emit ultrasound at frequencies between 20 and 100 kHz and detectable up to several meters away. This is the surprising discovery of Itzhak Khait and his colleagues from Tel Aviv University (Israel), whose article has just been published on the bioRxiv platform.
I think this concept is still worthy of scientific experiment, though I would not fund it. It would make a good learning exercise.berkeman said:Yikes! That looks like nonsense from what little I've translated from Italian...
Do not place a clear reflector around the plant, because that will block the wind and the rain.Sibilo said:Furthermore, ultrasound is also used to eliminate bacteria and fungi. tell me how long it will take to get the answer because I want to learn too
no berkerman that was the site from which they spoke in the conference, but it is not a technology already in use, but still to be testedberkeman said:Yikes! That looks like nonsense from what little I've translated from Italian...
The article mentioned at the end of that paragraph is at least in English: https://www.biorxiv.org/content/10.1101/507590v4 but it also appears to be self-published (not peer-reviewed). Do you know if this pre-print ever made it into a peer-reviewed journal?
Baluncore said:I think this concept is still worthy of scientific experiment, though I would not fund it. It would make a good learning exercise. Do not place a clear reflector around the plant, because that will block the wind and the rain.
You have one point source of ultrasound, and I believe you want to make a cylinder of sound that will enclose the plant with an isotropic level of sound, that penetrates the surface of the soil from above, to about 30 mm depth.
A radiating wave, from a point source, can be converted to a parallel beam by a parabolic reflector. That is the same principal as a satellite receiver dish.
A dish reflector would point downwards from above the plant, with the transducer at the focus, pointing upwards at the dish. The diameter of the dish will keep some rain off the plant, but sunlight and wind will enter from the side.
The reflected wave will arrive at the soil surface as a plane wavefront, so it should penetrate the surface soil evenly. I would not expect the wave to be reflected efficiently from the soil surface, unless it was flat and wet. Energy will be dispersed and lost in an open-structured soil with a rough surface.
The height of the dish above the ground is not critical, it can be raised as the plant grows.
I expect the dish diameter will be about 300 mm, which is 10 wavelengths at 30 kHz ≈ 5° beam sides. The ratio of focal length, to the diameter of the dish, will be determined by the radiation pattern of the ultrasonic transducer selected. The theory is the same as that of microwave dish "illumination".
The transducer specification, and the power level required, have not been specified.
From what little I read, it seemed to be saying that the plants communicate with each other above ground using ultrasound. Can you point to the part that you are asking about, where driving ultrasound into the root system helps to prevent fungal infestations and pests harming the plants? Thanks.Sibilo said:no berkerman that was the site from which they spoke in the conference, but it is not a technology already in use, but still to be tested
yes berkemann then as I have already told you this technology is still experimental and we take inspiration from that article, in short it is believed that through ultrasound the plant is able to grow and defend itself in a natural way without the aid of pesticides. but in that article this is not explicitly talked about but it was deducedberkeman said:From what little I read, it seemed to be saying that the plants communicate with each other above ground using ultrasound. Can you point to the part that you are asking about, where driving ultrasound into the root system helps to prevent fungal infestations and pests harming the plants? Thanks.
Well, at PF in the technical forums we require peer-reviewed journal literature to support discussions. If this is all still highly speculative and not published yet, we may need to shut down the thread.Sibilo said:yes berkemann then as I have already told you this technology is still experimental and we take inspiration from that article, in short it is believed that through ultrasound the plant is able to grow and defend itself in a natural way without the aid of pesticides. but in that article this is not explicitly talked about but it was deduced
No but in the article it is written that there is an ultrasound effect as communication between plants, but what I want to do is prove that ultrasound can help plants defend themselves, perhaps by communicating with each other. However, it doesn't seem right to close the thread just now that I was reaching a conclusionberkeman said:Well, at PF in the technical forums we require peer-reviewed journal literature to support discussions. If this is all still highly speculative and not published yet, we may need to shut down the thread.
the clues are there, we just need to verify in practice and I want to do itberkeman said:Well, at PF in the technical forums we require peer-reviewed journal literature to support discussions. If this is all still highly speculative and not published yet, we may need to shut down the thread.
https://www.google.com/url?sa=t&sou...IQFnoECAwQBQ&usg=AOvVaw296Z0s1WhBq2md9xEIMtNSberkeman said:Well, at PF in the technical forums we require peer-reviewed journal literature to support discussions. If this is all still highly speculative and not published yet, we may need to shut down the thread.