Tel Aviv: Since long, researchers have debated whether plants feel pain like human beings? Now, a new study says that just like people scream when in stress or pain, plants might do the same.

A team of scientists at Tel Aviv University have discovered that some plants emit a high frequency distress sound when they undergo environmental stress. To conduct this study, researchers placed microphones a few inches from tomato and tobacco plants, deprived them of water and cut their stems.

To their surprise, the plants emitted an ultrasonic signal between 20 and 100 kilohertz. When a tomato plant’s stem is cut, it emits 25 ultrasonic distress sounds over the course of an houranad when deprived of water, they emitted 35 ultrasonic sounds in an hour.

Although only tomato and tobacco plants were studied under the research , the scientists believe other plants may make sounds when stressed too.

“These findings can alter the way we think about the plant kingdom, which has been considered to be almost silent until now,” the study notes.

However, unlike human screams, plant sounds are too high-frequency, so it is not possible for us to hear them. But some plants and animals can hear the sounds coming from the distressed plants. The scientists also believed that insects notice the distress sounds before laying eggs on certain plants.

Enabling farmers to listen for water-stressed plants could “open a new direction in the field of precision agriculture”, the researchers suggest. They add that such an ability will be increasingly important as climate change exposes more areas to drought.