Plants emit sounds under stress: Israeli study

Israeli researchers found for the first time that plants emit sounds, the Tel Aviv University (TAU) said on Thursday, reported Xinhua.

In a new study, published in the journal Cell, TAU researchers found that the sounds emitted by plants are click-like, similar to popcorn popping, at a volume similar to human speech.

However, the sounds are emitted at high frequencies of 40 to 80 kHz, beyond the hearing range of the human ear, and can probably be heard by various animals, such as bats, mice, and insects.

These discoveries may change how people view the plant kingdom, which has been considered to be almost silent until now, according to the study.

It was also found that these sounds are mostly emitted when the plant is under stress, and contain information about its condition. Each plant and stress type is associated with a specific identifiable sound, the researchers noted.

In their study, the researchers recorded and analyzed sounds made by tomato, tobacco, wheat, corn, cactus, and henbit plants.

Machine learning algorithms developed by the team were ultimately able to identify the plant from sound recordings and determine the type and level of stress.

It was found that unstressed plants emitted less than one sound per hour, on average, while dehydrated or injured ones emitted dozens of sounds every hour.

The researchers noted that humans will also be able to utilize this sound information, given the right tools, such as sensors that tell growers when plants need watering.

Future studies planned by the team aim to find the mechanism behind the sounds, the way moths detect and react to them, and whether other plants could hear these sounds.