UNITED STATES – Scientists from the University of Madison-Wisconsin now have video footage of plants responding to injuries and it turns out it’s strikingly similar to how animals respond.
Plants don’t have a nervous system or any nerves at all, so to speak. So they don’t exactly “feel” pain but they do react in a way similar to us when we get hurt.
Scientists found out about this by genetically engineering a mustard plant to observe increases in calcium levels. For this to happen, the high tech proteins were introduced to the plants so that they would glow in the presence of calcium.
In case you didn’t know, excited animal nerve cells release glutamate which triggers electrically charged calcium ions waves that travel away from the area where that excitement was triggered.
When they cut the plant, amazing things started to happen as you can see in the video below. Lights flashed from the source of injury and spread to the entire plant in over a minute.
Through this we can see that calcium is involved in signalling in plants. The scientists also believe that glutamate is responsible for triggering this response, just like us!
Although the speed of signaling is not as fast as animal nerve signals which travels 120 metres a second (that’s 431 km/h!), you gotta give our green friends some respect!
The real purpose of this response
Once the warning signal spread throughout the plant, there will be a release of defensive hormones at the site of injury.
The hormones are a cocktail of chemicals that jump-start repair as well as noxious chemicals that ward against further attacks.
Some of these defence mechanisms are very sophisticated as in the case of grass. Know that familiar smell of a freshly mowed lawn? Turns out it’s the grass’ way of telling parasitic wasps to lay eggs in potential pests. That’s pretty metal.
This is not dissimilar to our fight-or-flight response. The only difference is that plants don’t have the privilege to run away from danger like we do. Instead, they have evolved to brace whatever nature throws at them.
So the next time you take a bite of that ulam, rest assured it’s not crying in pain, but feel free to picture all that glutamate and calcium signalling happening in your mouth!