"How Plants Secretly Talk to Each Other"

"The evidence for plant communication is only a few decades old, but in that short time it has leapfrogged from electrifying discovery to decisive debunking to resurrection. Two studies published in 1983 demonstrated that willow trees, poplars and sugar maples can warn each other about insect attacks: Intact, undamaged trees near ones that are infested with hungry bugs begin pumping out bug-repelling chemicals to ward off attack. They somehow know what their neighbors are experiencing, and react to it. The mind-bending implication was that brainless trees could send, receive and interpret messages.

The first few “talking tree” papers quickly were shot down as statistically flawed or too artificial, irrelevant to the real-world war between plants and bugs. Research ground to a halt. But the science of plant communication is now staging a comeback. Rigorous, carefully controlled experiments are overcoming those early criticisms with repeated testing in labs, forests and fields. It’s now well established that when bugs chew leaves, plants respond by releasing volatile organic compounds into the air...

To prove that electrical signals are at work, Ted Farmer’s team placed microelectrodes on the leaves and leaf stalks ofArabidopsis thaliana (a model organism, the plant physiologist’s equivalent of a lab rat) and allowed Egyptian cotton leafworms to feast away. Within seconds, voltage changes in the tissue radiated out from the site of damage toward the stem and beyond. As the waves surged outward, the defensive compound jasmonic acid accumulated, even far from the site of damage. The genes involved in transmitting the electrical signal produce channels in a membrane just inside the plant’s cell walls; the channels maintain electrical potential by regulating the passage of charged ions. These genes are evolutionary analogues to the ion-regulating receptors that animals use to relay sensory signals through the body. “They obviously come from a common ancestor, and are deeply rooted,” Farmer said. “There are lots of interesting parallels. There are far more parallels than differences.”...

the smell of cut grass — a blend of alcohols, aldehydes, ketones and esters — may be pleasant to us but to plants signals danger on the way."

http://www.wired.com/2013/12/secret-language-of-plants/

Whatttttt. I need to read some of these papers/make my plant geneticist friend read them and let me know how legit they are. But plants have a lot of neurotransmitters; I was just at a talk about how the GABA neurotransmitter is produced during the process that leads to alcoholism, and it turns out that it's not the typical enzymatic pathway, it's this secondary pathway that hasn't been studied that much and was first found in plants (where it has some other function).