We often associate plants with calm and tranquillity, however as it turns out, scientists have discovered they can actually be tranquillised further! A recent report in the Annals of Botany has found that similar to us humans, plants are also effected by general anaesthetic drugs. This discovery came as quite a surprise due to the fact plants do not possess a central nervous systems. But perhaps what is more interesting is the fact that scientists are still not entirely certain how these anaesthetics work on humans, let alone foliage!
Why tranquillise plants?
Authors of this new study, spearheaded by Italian and German plant biologists believe that testing general anaesthetic on plants could enable us to finally understand the drugs' 'mechanism of action'. They also stated their hope that plants could prove useful in developing and learning more about new anaesthetics. 'As plants in general, and the model plant [Arabidopsis] thaliana in particular, are suitable to experimental manipulation (they do not run away) and allow easy electrical recordings, we propose them as ideal model objects to study anaesthesia and to serve as a suitable test system for human anaesthesia,' they stated.
How do they do it?
Stefano Mancuso of the University of Florence and František Baluška of the University of Bonn gathered an array of plants that are known for movement, including the venus flytrap and mimosa pudica (shown to the left), a plant when touched, leaves fold in on themselves. They also looked at growing pea tendrils and carnivorous plants that have moving tentacles that ensnare prey.
Anaesthetics were then administered to the plants using several different methods - some were put in chambers and surrounded by xenon gas or deithyl ether vapour, whilst others had their roots exposed to lidocaine.
Through the use of each method, the plants were rendered temporarily unresponsive and still. The mimosa pudica's leaves remained still when touched and the Venus flytrap no longer closed when poked. The carnivorous plants did not attempt to bend upward to catch dead flies and the pea plant’s tendrils and curled up and drooped instead of spiralling upward.
While it's still not entirely clear how these common anaesthetics work, after these experiments, researchers feel they are getting closer to some reasonable hypotheses. It is thought that the drugs react to recepters on nerve cells or change the lipids (fats) in the membranes that surround nerves cells. Both of these could 'disable gated ion channels embedded in the membranes that control electrical impulses in nerves', which could explain how the drugs are able to cause temporary loss of conscious, immobility and pain perception.