These results were expected because a variety of plant species, including lima bean and maize, exhibit potent responses to VOCs. Moreover, several angiosperm plants have been reported to show enhanced direct and indirect defenses upon VOC-induced priming, following the transcriptional regulation of genes that mediate oxylipin signaling and defense responses [10,11]. Continuous air-pump and open-flow chamber systems would be useful for clarifying the mechanisms of plant-plant interactions via genetic manipulation and biochemical and ecological analyses.