Plants emit green leaf volatiles (GLVs) in response to insect or pathogen damage. GLVs consist of C6 and C9 aldehydes, alcohols, and their acetate esters, and play important roles in the plant defense response. One of the functions of GLVs in the defense response is priming. Plants pretreated by GLVs can induce a defense response more rapidly and effectively than unpretreated plants when they are damaged by pathogens or insects. In this study, we focused on the priming effects of GLVs on jasmonic acid response involved in the defense response. When Arabidopsis was pretreated with aldehyde GLVs, especially with (E)-2-hexenal, the anthocyanin content was significantly increased by a subsequent methyl jasmonate (MeJA) treatment. On the other hand, no effect of anthocyanin accumulation was observed for plants pretreated with alcohol GLVs. These results suggest that aldehyde GLVs, especially (E)-2-hexenal, could enhance sensitivity to MeJA in Arabidopsis. (C) 2012, The Society for Biotechnology, Japan. All rights reserved.