Plants do not suffer silently. Instead, plants emit “airborne sounds” when they are thirsty or stressed. cell.
Water-hungry plants and recently cut stems were found to emit up to about 35 sounds per hour. However, well-drained, uncut plants are much quieter, producing only about one sound per hour.
The reason you’ve probably never heard a thirsty plant make a noise is because the sound is ultrasonic, about 20 to 100 kilohertz. I mean, they were so shrill that most people couldn’t hear them. Bats, mice and moths could live in a world filled with the sounds of plants, and previous research by the same team found that plants also respond to sounds made by animals.
weeping crops
To bug the plant, Lilach Hadany and her colleagues at Tel Aviv University in Israel placed a cigarette (nicotiana tabacum) and tomatoes (solanum tomato) A plant in a small box with a microphone. The microphone picked up every sound the plant made, even if the researchers couldn’t hear it. Noise was particularly noticeable in plants stressed by lack of water or recent cuttings. When you lower the pitch of the sound and speed it up, “it’s a bit like popcorn. It’s a very short click,” Hadany said. “It’s not singing.”
Credit: Khait and Al
Plants have neither vocal cords nor lungs. According to Hadany, the current theory of how plants make noise centers on the xylem, the tubes that carry water and nutrients from the roots to the stems and leaves. The water in the xylem is held together by surface tension, just like water sucked out of a straw. Small pops may occur when air bubbles form or break in the xylem. Bubbles are more likely to form during drought stress. But the exact mechanism needs more research, Hadany says.
The team created a machine-learning model to infer with about 70% accuracy whether plants have been felled or were under water stress based on the sounds they make. This result suggests a possible role for plant voice monitoring in agriculture and horticulture.
To test the practicality of this approach, the team attempted to record plants in greenhouses. I was able to hear the plants with the help of a computer program trained to filter out background noise from wind turbines and air conditioners. A pilot study by the authors suggests that tomatoes and tobacco are not outliers. wheat (summer wheat), corn (There Mays) and wine grapes (vine) also makes noise when thirsty.
Chattering grass?
Previously, Hadany’s team had also studied whether plants could “hear” sounds, including the beach Evening Primors (Oenothera Drummondi) releases sweeter nectar when exposed to the sound of flying bees.
So, is plant noise an important feature of ecosystems, affecting plant and animal behavior? Graham Pike, former biologist and environmental science expert at Macquarie University in Sydney, Australia. The evidence is not yet clear, according to
He is skeptical that animals hear stressed plant moans. “It’s hard to imagine that these animals can really hear sounds at that distance,” he says. Further research should shed more light on this issue. But Pike says he’s fully willing to accept that plants “squeak” when they’re stressed.
This article is reproduced with permission and was first published on March 30, 2023.
