Tomato plants talk to themselves when approached by predators, study finds Plants throw hungry bugs off the scent by sending electrical commands to the fruit to release chemicals, making them taste unpleasant 20 July 2021 • 6:00am Hydrogen peroxide, the same chemical in hair dye, is one compound which increased in concentration after the electrical signals were triggered, according to researchers Credit: Moment RF/Getty Images The Very Hungry Caterpillar ate an apple, pears, plums, strawberries and oranges, but never a tomato. Had it tried, then the unsuspecting insect would have triggered an innate defensive mechanism of the fruit, which would make it taste worse – according to a study.