Submitted to: Journal of Chemical Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/8/2004
Publication Date: 4/20/2005
Citation: Gries, R., Khaskin, G., Gotoh, T., Schaefer, P.W., Gries, G. 2005. 2-methyl-(z,e)-7,9-octadecadiene: sex pheronome of lymantria bantaizana. Journal of Chemical Ecology. 31(4): 879-891. Interpretive Summary: As a close relative of the gypsy moth in Japan, Korea and China,Lymantria bantaizana feeds only on walnut, Juglans spp. We investigated the sex pheromone of this moth and found it communicates using a methylated diene hydrocarbon or 2-Methyl-(Z,E)-7,9-Octadecadiene. This finding can now be applied by using this compound as a lure in traps designed very specifically to trap only males of L. bantaizana.
Technical Abstract: Our objective was to identify the sex pheromone of Lymantria bantaizana (Lepidoptera: Lymantriidae) whose larvae defoliate walnut trees, Juglans spp., in China and Japan. Coupled gas chromatographic-electroantennographic (GC-EAD) detection analyses of pheromone gland extracts revealed a single EAD-active component. Retention index calculations of this compound on three fused silica columns (DB-5, DB-210, DB-23) suggested that it was a methylated octadecadiene with conjugated double bonds. In GC-EAD analyses of 2-methyloctadecenes, 2-methyl-(Z)-7-octadecene and 2-methyl-(E)-9-octadecene elicited the strongest antennal responses, suggesting that double bond positions were in C7 and C9. In comparative GC-EAD analyses of pheromone gland extract and stereospecifically synthesized isomers (E,E; E,Z; Z,E; Z,Z) of 2-methyl-7,9-octadecadiene, the (E,Z)- and (Z,E)-isomer had retention times identical to that of the candidate pheromone, but only the latter isomer had strong EAD-activity.Results of field experiments in Japan substantiated that 2-methyl-(Z,E)-7,9-octadecadiene is the L. bantaizana sex pheromone, a compound previously unknown in the Lepidoptera. Detection surveys in North America for exotic Eurasian forest defoliators should include traps baited with the L. bantaizana pheromone.