Whiteflies communicate before and during mating through abdomen oscillations which vibrations are believed to propagate mostly in the leaf (~100-400 Hz). They are very low-energy signals which are subject to low signal-to-noise ratio when recording them.
Gold-method to record substrate vibrations (ref), and as in the most recent study about whitefly vibration communication, is the the use of laser vibrometer. However, I don't have any. I have two possibilities:
- Microphone. One of the world-leading team working on whitefly vibratory communication put the edge of the subtrate leaf in contact with a paper which acts as a diffuser to amplify the diffused vibration to the air; then they use a microphone to pick the sound in the air. It looks like it requires a great deal of fineness to be sure that the leaf is well "connected" to the paper (whiteflies are pest that usually cannot be handled freely, so it adds some practical difficulty)
Kanmiya, Kenkichi (2006), Mating Behaviour and Vibratory Signals in Whiteflies (Hemiptera: Aleyrodidae), in Sakis Drosopoulos and Michael F. Claridge (Ed.), Insect sounds and communication : physiology, behaviour, ecology, and evolution.
- Piezo. This paper about low-cost methods to record substrate vibrations advises piezoelectric sensors, and their frequency response is adequate to my application. However, I've never seen any papers about whitefly recordings using piezo sensors.
I'd like to try the piezo method, as it would be easier for me to stick a piezo to the leaf rather than to design the great setup above. The piezzo has a greater self-noise but it measure the vibration directly, while I have very good low-noise microphones but the vibro-acoustic transduction between the leaf and the air will decrease the signal intensity.
Do you have any experience in this and what would you recommend between the two in term of signal-to-noise ratio?
PS: this question is not about the technics to attach the piezzo for which I made a specific question