The female sex pheromone composition and the male electro-physiological response with respect to the three main sex pheromone components, (Z)-5-decenyl acetate, (Z)-7-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, were investigated in populations ofAgrotis segetum from Armenia and Bulgaria. The percentage composition of the female-produced pheromone was 1∶52∶47 and 1∶42∶57 for the respective populations. Corresponding male receptor frequencies were 9∶90∶1 and 6∶92∶2. EAG response profiles of the male antennae were similar for the two populations. The populations from Armenia and Bulgaria differed from the earlier investigated French and Swedish populations, which have larger amounts of (Z)-5-decenyl acetate in gland extracts and have a majority of (Z)-5-decenyl acetate-sensitive receptors. Investigation of receptor frequencies on antennae of male Hungarian moths showed that individuals could be classified as either Swedish or Armenian/Bulgarian type. Males of the Swedish type were preferentially attracted to the three-component pheromone blend, whereas blends of (Z)-7-dodecenyl and (Z)-9-tetradecenyl acetate, and (Z)-7-dodecenol [pure or in mixture with (Z)-5-decenol] attracted the Armenian/Bulgarian type. The nature of pheromone variation among European and Asian populations of the turnip moth and possible mechanisms maintaining the variation are discussed.

Selected combinations of (Z)-5-decenyl, (Z)-7-dodecenyl, and (Z)-9-tetradecenyl acetates, the pheromone components of the turnip mothAgrotis Segetum were tested for field attractancy at six, two, and three sites in Europe, Asia, and Africa, respectively. At all of the sites in Eurasia and in northern Africa the ternary mixture of the acetates captured most males, while at the sites south of the Sahara in Africa, (Z)-5-decenyl acetate alone was responsible for attraction. Differences in male attraction among the populations studied confirm the existence of significant population variation in the pheromone ofA. segetum. Interpretation of the present results together with earlier studies suggests that this variation is more or less continuous in Eurasia and north Africa, while a clearly distinct pheromone type is present in the areas south of the Sahara desert.

Recently, the distribution of the Mediterranean cedar bark beetle, Phloeosinus aubei Perris (Coleoptera: Scolytidae), has expanded to Central Europe. Reported mostly on cypress in the Mediterranean area, potential host plants in the invaded range include other scale-leafed conifers, such as cultivars of arborvitae, Thuja occidentalis L. To reveal potential kairomonal cues for P. aubei, volatiles of T. occidentalis were collected and analysed by gas chromatography with electroantennographic detection (GC-EAD). Assignments of chemical structures of antennally active components were carried out by gas chromatography linked to mass spectrometry (GC-MS) using authentic reference samples. Antennal responses to synthetic samples of the identified compounds were studied by electroantennography (EAG), with antennae of female and male P. aubei. GC-EAD analysis of head space volatiles of T. occidentalis revealed 22 antennally active compounds, of which 21 were identified. The most abundant components were a-and bthujone, fenchone, camphor, terpinen-4-ol, bornyl acetate and a-terpinyl acetate, all of which are oxygenated monoterpenes. When EAG activities of synthetic samples were compared, the most intensive responses from female antennae were elicited by a mixture of a-and b-thujone, followed by (-)-terpinen-4-ol, (+)-camphor, cis-4-thujanol, (+)-sabina ketone, (+)-terpinen-4-ol, isopulegone, (-)-fenchone, borneol, (3Z)-hexen-1-ol, (-)-1-octen-3-ol and (+)-sulcatol. Male antennae responded the most to (-)-terpinen-4-ol and cis-4-thujanol followed by the mixture of a-and b-thujone. The next highest responses were elicited by (+)-camphor, borneol, (+)-terpinen-4-ol, (+)-sulcatol and (+)-sabina ketone. Striking differences were found between responses to the enantiomers of fenchone, sulcatol and 1-octen-3-ol, whereas responses to the enantiomers of terpinen-4-ol did not differ significantly from each other. Several antennally active volatiles of T. occidentalis have also been reported from cypress and various other members of the Cupressaceae, suggesting that the sensory apparatus of P. aubei may recognize the shared components, which may enable rapid adaptation to new hosts in the invaded areas.

In field trapping tests conducted in Hungary large numbers of Pyralis costalis F. (Lepidoptera: Pyralidae), a secondary pest, were attracted to traps baited with iso-amyl alcohol (3-methyl-1-butanol) and acetic acid. The same bait attracted lower numbers of P. farinalis L., a well-known stored product pest. In both spp. the capture of the two-component blend was significantly higher than the catch in traps with the single components. In tests conducted in a country mill, the blend of the above two compounds proved to be attractive towards Anagasta kuehniella Zell. and Plodia interpunctella Hbn. (Lepidoptera: Phycitidae), both important pests of stored products worldwide. The majority of captured insects were females. The optimal ratio for attracting A. kuehniella was 1:1 to 1:10 iso-amyl alcohol:acetic acid. The related iso-amyl acetate was inactive. The addition of iso-butyl alcohol (2-methyl-1-propanol) did not influence activity of the iso-amyl alcohol / acetic acid blend. Polyethylene dispensers with 0.2 ml of the blend started to loose activity only after 3 weeks of field exposure. Application possibilities of the newly discovered attractant are discussed.

Enantiomer separation of (6Z,9Z)-cis-3,4-epoxynonadecadiene and (3Z,9Z)-cis-6,7-epoxynonadecadiene could be achieved using chiral high-resolution gas chromatography and a cyclodextrin-bond column. (3Z,9Z)-(6R,7S)-Epoxynonadecadiene was identified from ovipositor extracts ofColotois pen-Naria, while inErannis defoliaria the 6S,7R-enantiomer was found. In field trapping tests pure synthetic enantiomers caught only conspecific males of these species. (3Z,6Z,9Z)-Nonadecatriene was found in both species, while the presence of (3Z,6Z,9Z)-heneicosatriene was indicated inC. Pennaria only. A 10∶10∶3 blend of (3Z,9Z)-(6R,7S)-epoxynonadecadiene, (3Z,6Z,9Z)-heneicosatriene, and (3Z,6Z,9Z)-nonadecatriene was found to be optimal for catchingC. Pennaria, whileE. Defoliaria males were optimally caught by a 1∶1 mixture of (3Z,9Z)-(6S,7R)-epoxynonadecadiene and (3Z,6Z,9Z)-nona-decatriene. (6Z,9Z)-(3S,4R)-Epoxynonadecadiene was identified from ovipositor extracts ofAgriopis (Erannis) aurantiaria. In field tests the pure enantiomer proved to be a highly specific sex attractant for both the late autumn/early winter flyingA. Aurantiaria and the late winter/early spring flyingA. Leucophearia. Males ofAgriopis marginaria, which fly in late winter/early spring, were attracted to (3Z,9Z)-(6S,7R)-epoxynonadecadiene. The addition of (3Z,6Z,9Z)-nonadecatriene to theS,R-enantiomer increased captures. Optimal catches were recorded with a 10∶3 epoxide-hydrocarbon blend. Enantiomer specificity in all species was confirmed in EAG measurements.

Short-chain unsaturated chiral methyl carbinols are identified as a new class of lepidopteran pheromone components. The natural female-produced pheromone of the banded apple pigmyStigmella malella (=Nepticula malella) (Stainton) (Lepidoptera: Nepticulidae) was identified to be a mixture of (S)-(E)-6,8-nonadien-2-ol and (S)-(Z)-6,8-nonadien-2-ol. For monitoring traps, a 10:3E:Z blend at 100-1000 µg is recommended. It is suggested that pheromones with similar structures may be specific to Nepticulidae and other related microlepidopteran families.

Four compounds, tetradecyl acetate, (Z)-9-tetradecenyl acetate, (E)-11-tetradecenyl acetate and (Z)-ll-tetradecenyl acetate were identified from female sex pheromone extracts of Hungarian and Egyptian lima-bean pod borers (Etiella zinckenella Tr., Lepidoptera: Phycitidae) by gas chromatography with flame ionization (FID) and electroantennographic (EAD) detection. In EAG studies these monounsaturated acetates gave the best responses in a series of other tetradecenyl acetates and tetradecenols. The four component blend of the identified components in similar ratios as in the pheromone extract attracted significant numbers of male lima-bean pod borers in both Hungary and Egypt. In a preliminary subtraction test best capture was achieved by the ternary mixture of the monounsaturated acetates.

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