Reading - Part 1

Read the text. Fill in each gap with ONE word. You must use a word which is somewhere in the rest of the text.

Plants 'talk' when stressed

Plant lovers believe that talking to plants helps them grow. Scientists have discovered there could be a grain of truth in this belief. Researchers have discovered that (1) emit sounds when they are stressed. The noises are akin to a human cry or scream. The scientists believe the (2) are specific enough for us to be able to interpret them and to attend to their needs. Unfortunately, plant sounds are at too high a frequency for the human ear to pick up. Humans can only hear frequencies of up to 16 kilohertz. The (3) used special AI algorithms to detect ultrasonic sounds emitted by plants that were up to 250 kilohertz. The AI also differentiated between different types of plant sounds. The research was conducted in an acoustic chamber in an adapted greenhouse at Israel's Tel Aviv University. Scientists discovered that vibrations from (4) tobacco and tomato plants turned into sound waves. Lead researcher Professor Lilach Hadany said: "Plants usually (5) sounds when they are under stress. Each plant and each type of stress is associated with a specific identifiable sound." She suggested that fields of crops could be quite noisy, saying: "While imperceptible to the human ear, the sounds emitted by plants can be heard by bats, mice, and insects." Interpreting these sounds could help us understand when (6) are dehydrated. Farmers could irrigate their crops more efficiently, and thus conserve water.