Accordingly, we shifted from the ‘‘open-flow chamber’’ to a greenhouse study during the current study. To the best of our knowledge, there has been no similar attempt at combining the two systems. Although it would be best to conduct studies in the field, studies cannot be conducted with genetically modified (GM) plants in the field in Japan. This restriction, in turn, encouraged us to carry out greenhouse experiments, but without climate control. In the greenhouse experiments, it was found that T. urticae females laid their eggs on VOCos-receiver lima bean leaves at the same level as on VOCwt- receiver leaves (Figure S2). This was probably due to the weaker atmospheric impact of airborne signals in the greenhouse (without air-flow) compared to the open-flow system (with air-flow). These findings are in line with the report from [30] that b-ocimene has no detectable effect on the priming or induction of the secretion of extrafloral nectar in naturally growing lima bean tendrils. Therefore, different environments (open-flow chamber,green- house,field) seem to differently affect whether and how receiver plants respond by undertaking defensive actions.