When Plants Sense Danger, They Cry Out With Calcium

17:34 minutes

a gif of the veins of a leaf glowing and dimming
Calcium signals move through a leaf in response to wounding of a different, distant leaf. Credit: Masatsugu Toyota

Plants have a unique challenge in staying alive long enough to produce offspring. Unable to move and at the mercy of their surroundings, they present a tempting source of nutrition for bacteria and animals alike. But they’re not helpless. Botanists have long known plants are capable of sensing their environments and responding to them. They can grow differently in response to shade or drought, or release noxious chemicals to fend off predators, even as a caterpillar is mid-way through chewing on a leaf.

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But how does that information travel? New research published in the journal Science shows a first glimpse, in real time, of distress signals traveling from one leaf, snipped, crushed, or chewed, to other healthy leaves in the same plant. The signal, a wave of calcium ions, seems linked to the amino acid glutamate, which in animals acts as a neurotransmitter.

University of Wisconsin-Madison botany professor Simon Gilroy, a co-author on the new research, explains this chemical signaling pathway and other advances in how we understand plant communication. Plus, why research on plants in zero gravity is still a barely explored but vital frontier in how we understand their biology.

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Segment Guests

Simon Gilroy

Simon Gilroy is a professor of botany at the University of Wisconsin-Madison.

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About Christie Taylor

Christie Taylor is an associate producer for Science Friday. Her day involves diligent research, too many phone calls for an introvert, and asking scientists if they happen to have an audio recording of their research findings.

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