Plants talk

Plants respond to herbivore attack by releasing volatile organic compounds (VOCs) that function as a defense by attracting natural enemies of the herbivore, thereby establishing defensive mutualisms with insects. The fact that plants use VOCs to communicate with insects generates the expectation that they also use VOCs to communicate with each other. Numerous studies have examined the question of whether un-attacked neighboring plants growing adjacently to attacked plants use these VOCs to anticipate future attack and preemptively activate defense responses. Most of these experiments have been carried out under experimental conditions that unnaturally amplify or distort the effects of the VOCs on neighboring plants and none have conclusively identified the active constituents of the VOC bouquet that function as signals. Scientists from the Max Planck Institute for Chemical Ecology in Jena present a new experimental approach to these challenges that allows for the study of plant-plant signaling under natural conditions.