Sex Pheromone and Related Compounds in the Ishigaki and Okinawa Strains of the Tussock MothOrgyia postica(Walker) (Lepidoptera: Lymantriidae)

Abstract

Two distinct electroantennographycally active (EAG-active) components, A and B, and a weakly active component C were found in a solvent extract from virgin females of the Ishigaki strain of the tussock moth, Orgyia postica (Walker). Components A, B, and C were found in the extract of the females at 4.0, 0.5, and 4.0 ng/female respectively. Components A, B, and C were identified as (6Z,9Z,11S,12S)-11,12-epoxyhenicosa-6,9-diene [(11S,12S)-1: posticlure], (6Z)-henicos-6-en-11-one (2), and (6Z,9Z)-henicosa-6,9-diene (3), respectively. Component B was absent in the extract from the Okinawa strain, in which components A and C were present at 2.0 and 1.5 ng/female respectively. (11S,12S)-1 and the racemic mixture showed attractiveness for both the Okinawa and Ishigaki strains, whereas (11R,12R)-1 did not. The addition of 2 significantly reduced the trap catches with (11S,12S)-1 on the Okinawa strain which lacked 2, while there was no significant inhibitory effect on the Ishigaki strain. The addition of 3 to (11S,12S)-1 did not significantly affect trap catches at Ishigaki or Okinawa. This confirmed that the attractant pheromone of O. postica of the Ishigaki strain is also (11S,12S)-1.

Lepidopteran Sex Pheromones

“…With the epoxidation of these polyenes, novel components are created such as 9,10-epoxides derived from 1,Z3,Z6,Z9-tetraenes (1,Z3,Z6,epo9-20:H and 1,Z3,Z6,epo9-21:H) [56] and a 4,5-epoxide derived from E4,Z6,Z9-diene (t-epo4,Z6,Z9-19:H) [9]. The 4,5-epoxide has a trans-epoxy ring.Another pheromone compound with a trans-epoxy ring, Z6,Z9,t-epo11-21:H from the tussock moth in Lymantriidae [66,67], could be biosynthesized from the corresponding triene (Z6,Z9,E11-21:H). This intermediate, however, has not been found in insects.…”

“…The kinds of available chiral columns and their resolution capabilities are described later. Table 3 shows the absolute configuration of some natural pheromones as analyzed by chiral chromatography and the attractive activity of synthetic epoxides in the field [67,[71][72][73][74][75][76]. Interestingly, males were not always effectively attracted by the synthetic epoxide despite exhibiting the same configuration as produced by the corresponding females.…”

“…Additionally, the stereochemistry of a cis-epoxy ring in disparlure (Me2,epo7-18:H of Lymantria dispar) [112], two cis-epoxy rings in a diepoxy pheromone component (epo3,epo6,Z9-21:H of Perina nuda) [70], and a trans-epoxy ring in posticlure (Z6,Z9,t-epo11-21:H of Orgyia postica) [67] were defined by the same column. Besides analysis with a UV detector or RID, quantitative GC analyses of the chiral HPLC eluants have confirmed some assignments of the stereochemistry [67,70,72,76].…”

“…The coupling constant between two olefinic protons with an E configuration (~15 Hz) is bigger than the coupling constant in those with a Z configuration (~10 Hz), and the constant between two protons on a cis-epoxy ring (~5 Hz) is bigger than that on a trans-epoxy ring (~2.5 Hz). The Z-double bond of the Thaumetopoea pityocampa pheromone (ϵ11,Z13-16:OAc) [45] and the transepoxy ring of the Orgyia postica pheromone (Z6,Z9,t-epo11-21:H, posticlure) [66,67] were determined by FT-NMR analysis of the natural products. The pheromone titers of these species are rather high, and about 10 mg of the components was used for the NMR analysis.…”

The egg parasitoid Telenomus euproctidis (Hymenoptera: Scelionidae) uses sex pheromone released by immobile female tussock moth Orgyia postica (Lepidoptera: Lymantriidae) as kairomone

“…postica, is a unique trans-epoxide, (6Z,9Z,11S,12S)-11,12-epoxy-6,9-henicosadiene (Wakamura et al 2001(Wakamura et al , 2005. This compound has a quite different chemical structure from the other two tussock moth species (Fig.…”