Plantwatch: how come plants can be anaesthetised?

Plants can be anaesthetised. When the sensitive Mimosa pudica is touched its leaves fold up, and in 1878 the French physiologist Claude Bernard anaesthetised the plant using ether, preventing the leaf movements. Since then other plant movements have been anaesthetised – but how these drugs work has been a mystery.

Plants can send electrical signals similar to nerve impulses. The Venus flytrap has an electrical signal that tells it to shut down if you touch atrigger hair.

A recent study shows that ether can block the electrical signal in flytraps. The flytraps were paralysed, but the triggering hairs of adult plants remained touch-sensitive.

The key to this puzzling behavior is a gene that is only found in the adult flytrap. In animals, glutamate is a chemical that passes messages between nerves, and in the anaesthetised flytrap the glutamate receptor was blocked, jamming the electrical signal and trap movement.

Plants and animals share some features of a nervous system that could shed light on how anaesthetics work in animals and humans.