In order to assess the impact of manipulated VOCs on plant- plant communications, we generated transgenic plants that constitutively biosynthesize and emit VOCs. We prepared gene constructs consisting of lima bean (E)-b-ocimene synthase PlOS [23] inserted downstream of the constitutive 35S cauliflower mosaic viral (CMV) promoter, and successfully generated a set of independent transgenic tobacco lines. Four representative exam- ples exhibiting substantial trans-gene (PlOS) expression and (E)-b- ocimene emission are shown in Figure 1.