Electrical signals within plant tissue have been studied since the 1800s. Charles Darwin was interested in possible electrical signals in the Venus Flytrap mechanismplugin-autotooltip__plain plugin-autotooltip_bigVenus Flytrap mechanism

The Venus Flytrap (Dionaea muscipula) is a well-known carnivorous plant native to the sub-tropical wetlands of the US.

The 'trap' structure snaps shut when insects or spiders repeatedly touch specialised 'trigger hairs' on the trap's upper surface. (which is still not completely understood). In the 1920s Jagadish Chandra Bose investigated what he called The Nervous Mechanisms of Plants. His experiments, mainly on tomato plants, were not considered scientifically sound by modern day standards, and were largely forgotten.

The ideas are now under investigation again. See, for example, a report the Journal of Experimental Botany, Volume 61, Issue 13, pp. 3697–3708, one of many studies which have confirmed that plants do create relatively high-speed electrical signals (conducted through phloem and sieve-tubes), particularly when stressed.

Despite the resurgence of interest, very little is currently known about the purpose(s) of the electrical signals - though they do seem to be largely associated with plant damage, and may be involved in protection mechanisms against herbivores. Their implications for plant 'sensing' in general are largely unknown.

Also see : Plant communicationplugin-autotooltip__plain plugin-autotooltip_bigPlant communication

In the past few decades, progress has been made in various areas of plant communication studies.

It's now confirmed that individual plants can 'communicate' with each other by various means. e.g. by :

* The release of airborne Volatile Organic Chemicals (VOCs), which are sensed by other plants. and Electrical activity in fungiplugin-autotooltip__plain plugin-autotooltip_bigElectrical activity in fungi

It's been established that many species of fungi generate small electric potentials (c. 100 mV) in their webs of underground fibres.

It's unknown what significance these electrical potentials may or may not have. Some research groups have suggested that they could form the basis of 'signals' between fungi - or even between the fungi and nearby plants.