BEIJING, Dec. 24 (Xinhua) — Scientists say some plants emit “high-frequency screams” when they are under environmental pressure, but the sound is high-frequency ultrasound, the Daily Mail of London reported. The researchers, who squeezed water from tomatoes and tobacco plants and cut off the stems and leaves, then placed a megaphone at a distance of 10 cm to record the plant’s reaction, and found that the two plants, when injured, released 20-100 kHz of ultrasound and passed them to nearby plants and organisms. At the same time, the experiment showed that when the tomato plant’s stems and leaves were cut off, it would send out 25 ultrasonic screams in an hour.
When the stems and leaves of tobacco plants are removed, they make 15 painful sounds, and when the researchers squeeze water from each plant, the tomato strains make more painful sounds, releasing 35 in an hour, while the tobacco plants emit only 11, which seem to produce different distress signals for different environmental pressures, with differences in strength and frequency.
The team observed that tobacco plants made a greater cry for help when they were squeezed out of water than cutting off the stems and leaves, compared with plants that were not directly threatened or damaged by the environment, releasing an average of less than one ultrasonic signal per hour.
The researchers used data from machine learning models to predict different frequency sounds that plants might release in other conditions, such as windy weather and heavy rain.
The new findings could change our perception of plants, which have previously been thought to be silent about injuries and do not seem to be as stressful as animals. The researchers used data from machine learning models to predict different frequency sounds that plants might release in other conditions, such as windy weather and heavy rain.
The team believes that listening to plants release different types of sounds can help achieve precision agriculture, while helping farmers identify potential problems with crops with less speculative work.
Last year, another study confirmed that when some plants are uprooted or even touched by leaves, they release unpleasant chemicals that are likely to drive away insects.
When a worm bites a plant leaf, the leaves release calcium at the wound, causing a chain reaction of the plant leaves and stem dry, which will spread throughout the plant for about 1-2 minutes, and calcium produces a hormone that protects the plant leaves.
Some plants also release toxic chemicals that can cause adverse taste stimuli to invasive insects, such as grass escloser hormones that attract nearby parasitic bees to devour insects that attack the grass. (Ye Ding Cheng)