title: (Z,Z)-6,9-heneicosadien-11-one, labile sex pheromone of the whitemarked tussock moth, Orgyia leucostigma.
abstract: The whitemarked tussock moth (WMTM), Orgyia leucostigma (J. E. Smith), is a major pest of coniferous and deciduous trees in eastern Canada. Chemical identification of its sex pheromone depended primarily on GC-EAD and HPLC analysis, with confirmation of behavioral activity by wind tunnel and field tests. We identified (Z,Z)-6,9-heneicosadien-11-one (Z,Z-6,9-ket) at 4-5 ng/female as the only essential sex pheromone component. Also detected in female extracts were (Z)-6-heneicosen-11-one (Z6-ket) at 2.5 ng/female, (Z,E)-6,8-heneicosadien-11-one (Z,E-6.8-ket) at about 0.5 ng/female, and a trace amount of (Z,E)-6,9-heneicosadien-11-one. Traps containing as little as 1 microg of Z,Z-6,9-ket attracted males at low population levels, indicating it is a potent sex attractant. Traps baited with Z6-ket attracted few males, and in windtunnel bioassays it was at least 100-fold less attractive to males than Z,Z-6,9-ket. No improvement in trap catch occurred with the addition of Z6-ket in various binary mixtures with Z,Z-6,9-ket, including the female ratio, and a ternary mixture of Z,Z-6.9-ket, Z6-ket, and Z,E-6,8-ket in the 9:5:1 ratio detected in females was no better than Z,Z-6,9-ket alone. We attribute the presence of Z,E-6,8-ket and Z,E-6,9-ket in female extracts to the spontaneous and rapid stereospecific isomerization of Z,Z-6,9-ket at room temperature. Male flight began at sunset but peaked during the second half of the night.
authors.affiliation: Canadian Forest Service, Natural Resources Canada, 1219 Queen St. E., Sault Ste. Marie, Ontario, Canada P6A 2E5. ggrant@nrcan.gc.ca
authors.forename: Gary G
authors.initials: GG
authors.lastname: Grant
authors.forename: Keith N
authors.initials: KN
authors.lastname: Slessor
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Mamdouh M
authors.initials: MM
authors.lastname: Abou-Zaid
mesh_terms: D000818:Animals; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D005233:Fatty Alcohols / Q000737:chemistry; D005260:Female; D008297:Male; D009036:Moths / Q000502:physiology*; D012724:Sex Attractants / Q000737:chemistry / Q000502:physiology*; D012726:Sexual Behavior, Animal / Q000502:physiology*
chemical_list: C477785:6,9-heneicosadien-11-one; D005233:Fatty Alcohols; D012724:Sex Attractants