Artifacts and Pheromone Blends from Nezara spp. and Other Stink Bugs (Heteroptera: Pentatomidae)

Isomeric compounds reportedly released by mature males o f Nezara viridula as attractants for conspecific females are evidently artifacts formed by dimerization o f (£)-4-oxo-2-hexenal. Additional analyses o f the male-specific volatiles from Italian, Australian, Brazilian, and Jap­ anese populations o f N. viridula verify that at least two distinctive pheromone strains exist, but an active synthetic pheromone has not yet been developed. Analyses o f volatiles from N. antennata and Acrosternum aseadum males are also reported showing that the native Japanese Nezara sp., and species in the sister genus Acrosternum, produce species-specific blends based on the same compounds as N. viridula: (Z)-a-bisabolene (l-m ethyl-4-(l,5-dim ethyl-(Z)-l,4hexadienyl)-cyclohexene), and transand cis1,2-epoxides o f (Z)-a-bisabolene. The trans-/cisI,2-epoxide ratio o f N. antennata is within the range found for most N. viridula populations, but the blend from Japanese N. viridula males deviates radically from those o f other conspe­ cific populations.