In the current study, we found that transgenic-plant-volatiles (VOCos), which included (E)-b-ocimene, from PlOS-overexpress- ing plants, primed defense responses to herbivory in eavesdrop- ping bean and maize plants. We examined these responses under two experimental conditions using an ‘‘open-flow chamber’’ and a ‘‘greenhouse without climate control’’.These experiments con- firmed the importance of relying on realistic experimental conditions for plant-plant communication studies Firstly, in our ‘‘open-flow’’ condition, both induced direct and indirect defenses (reflected by reduced development/reproduction and attraction of predators) were found to be primed by exposure to