Interaction of aggregation pheromone components of the bean bug, Riptortus clavatus (Thunberg) (Heteroptera: Alydidae)

The aggregation pheromone of the bean bug, Riptortus clavatus, consists of three components; (E)-2-hexenyl (Z)-3-hexenoate (E2HZ3H), (E)-2-hexenyl (E)-2-hexenoate (E2HE2H), and myristyl isobutyrate (MI). The role of each component to attract the bug was tested in the field using synthetic chemicals. The effectiveness of using E2HZ3H, E2HE2H, or MI alone to attract R. clavatus did not vary from that of the control. Blends of E2HZ3H+E2HE2H showed no attractiveness to R. clavatus, however, the addition of MI to E2HZ3H+E2HE2H (tertiary blend) showed significantly higher attractiveness to the bug than that of the control. The E2HE2H+MI blend was also equally attractive to the tertiary blend. A mixture of 7 mg MI with E2HZ3H (7 mg) and E2HE2H (36 mg) rivaled the single use of 100 mg MI in attractiveness. These findings indicate that MI can exert full attractiveness to the bug only in the presence of E2HZ3H and E2HE2H.