Although it has been revealed in recent years that plants are capable of seeing, hearing and smelling, they are still usually thought of as silent. But now, for the first time, they have been recorded making airborne sounds when stressed, which researchers say could open up a new field of precision agriculture where farmers listen for water-starved crops.
Itzhak Khait and his colleagues at Tel Aviv University in Israel found that tomato and tobacco plants made sounds at frequencies humans cannot hear when stressed by a lack of water or when their stem is cut.
[Editor’s note: This preliminary study has not been published in a peer-reviewed journal yet.]
Microphones placed 10 centimeters from the plants picked up sounds in the ultrasonic range of 20 to 100 kilohertz, which the team says insects and some mammals would be capable of hearing and responding to from as far as 5 meters away. A moth may decide against laying eggs on a plant that sounds water-stressed, the researchers suggest. Plants could even hear that other plants are short of water and react accordingly, they speculate.
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.
Read full, original article: Recordings reveal that plants make ultrasonic squeals when stressed