Sex pheromone of the fall webworm moth,Hyphantria cunea

Three compounds have been identified as sex pheromone components produced by female fall webworm moths,Hyphantria cunea (Drury). These compounds are: (Z,Z)-9,12-octadecadienal (I), (Z,Z,Z)-9,12,15-octadecatrienal (II), and (Z,Z)-3,6-cis-9,10-epoxyheneicosadiene (III). The ratio of these compounds was approximately 5613, respectively, in female tip extracts prepared from U.S.S.R, insects and approximately 1821, respectively, in extracts from U.S. insects. The ratio in female effluvia trapped from U.S. insects was 1627, respectively. Compound III plus either I or II is effective in eliciting upwind flight in a wind tunnel. Compounds I, II, and III are also components of the sex pheromone system of the saltmarsh caterpillar moth,Estigmene acrea (Drury).Lepidoptera: Arctiidae.Part of this work was carried out under the sponsorship of the U.S.A.-U.S.S.R. Scientific Exchange Program and the U.S.S.R. Ministry of Agriculture. It was also supported in part by National Science Foundation grant PCM78-13241. These results were first disclosed at the EUCHEM Conference on Chemistry of Insects, held at Borgholm, Sweden, on August 13–17, 1979. We sadly note the passing away of our distinguished colleague and friend, Dr. A.S. Hill.     

Sex pheromone of the chokecherry leafroller moth,Sparganothis directana

(E)-9,11-Dodecadienyl acetate and (Z)-9,11-dodecadienyl acetate in conjunction with (E)-11-tetradecenyl acetate and (Z)-11-tetradecenyl acetate were found to comprise the sex pheromone ofSparganothis directana, based on chemical analysis, electroantennogram tests, and field trapping. (E)-9-Dodecenyl acetate and (Z)-9-dodecenyl acetate were also found in gland extracts but did not influence trap catches. The relative amounts of these compounds in the gland were 3521928 106, in the order named. Only (E)-9,1 1-dodecadienyl acetate, (E)-11-tetradecenyl acetate, and (Z)-11-tetradecenyl acetate were required for attraction of males to traps, dispensed in the relative amounts 501238, respectively.Lepidoptera: Tortricidae.Supported by National Science Foundation grant PCM 78-13241.     

Sex pheromone components of corn stalk borerSesamia nonagriodes (Lef.) isolation,identification, and field tests

Z-11-Hexadecenyl acetate (Z11–16OAc), dodecyl acetate (12OAc),Z-11-hexadecenal (Z11–16Aid), andZ-11-hexadecenol (Z11– 16OH), were found in pheromone gland extracts of femaleSesamia nonagriodes (Lef.) [Lepidoptera: Noctuidae]. These four components were also present in airborne volatiles collected from calling virgin females in a 651889 ratio. Hexadecyl acetate (16OAc) was also detected but found to be inactive. The identification was based on multicolumn GC analysis, mass spectrometry, and field activity.Z11–16OAc is the major sex pheromone component; the addition of the secondary components individually decreased male captures. The blend of the four synthetic components in 691588 ratio was highly attractive to males; 200 g per trap was the most effective concentration in field tests.Lepidoptera: Noctuidae     

Sex pheromone evidence for two distinct taxa withinGraphania mutans (Walker)

The sex pheromones of two populations ofGraphania mutans (Walker) were analyzed. Females from an Auckland population produced (Z)-9-tetradecenol (Z9-14OH), (Z)-9-tetradecenyl acetate (Z9-14OAc), (Z)-7-tetradecenol (Z7-14OH) and (Z)-7-tetradecenyl acetate (Z7-14OAc), while females from a Lincoln population produced these four compounds and a large amount of (Z)-9-tetradecenal (Z9-14Ald). Significant differences, paralleling the difference between females, were observed when the responses of males of both populations to the above and other related compounds were tested by electroantennogram, field-trapping, and wind-tunnel bioassays. The most distinct difference was observed in the wind tunnel. Males from both taxa flew upwind and touched pheromone sources containing sex pheromone extract of females of their own taxon, but either did not initiate upwind flight or arrested upwind flight shortly after taking flight in response to extract from females of the other taxon. The difference between the pheromone systems of the two populations is probably due to the presence and importance of Z9-14Ald in the pheromone blend of the Lincoln population. Thus the addition of a relatively large amount of Z9-14Aid to a four-component pheromone blend (i.e., Z9-14OH, Z9-14OAc, Z7-14OH, andZ7-14OAc) attractive to Auckland males completely suppressed trap catches of male G.Mutans in Auckland but large numbers of males were caught at both Lincoln and Nelson in traps baited with this five-component blend. In wind-tunnel studies, the addition of even small (1% of amount of Z9-14OH) amounts ofZ9-14Ald to the four-component blend resulted in a significantly greater proportion of Auckland males arresting upwind flight than to the four-com ponent blend. It is suggested that these two populations of G. nations represent distinct sibling species within the described concept.LepidopteraNoctuidaeHadeninae.     

Compounds modifying male responsiveness to main female sex pheromone component of the currant borer,Synanthedon tipuliformis clerk (Lepidoptera: Sesiidae) under field conditions

Various blends of (E,Z)-2,13-octadecadien-1-ol acetate (E,Z2,13-18: OAc), (Z)-13-octadecen-1-ol acetate (ZOAc) (two previously identified pheromone components of the currant borer,Synanthedon tipuliformis females), (E,Z)-, (Z,Z)-3,13-octadecadien-1-ol acetates (E,Z- andZ,Z3,13–18:OAc), andZ,Z-3,13-octadecadien-1-ol (Z,Z3,13–18:OH) were evaluated in field traps in three geographic regions. MaleS. tipuliformis were attracted toE,Z2,13–18:OAc in Tasmania, New Zealand, and Hungary. Captures were not influenced by the addition ofZ13–18: OAc, tested in Tasmania and Hungary. In Hungary and New Zealand, the addition ofE,Z3,13–18: OAc toE,Z2,13–18:OAc in a ratio of 100:3 was strongly synergistic; however, in Tasmania captures were reduced. The addition ofZ,Z3,13–18: OAc toE,Z2,13–18:OAc in a ratio of 101 resulted in strong inhibition of trap captures in Hungary. WhenZ,Z3,13–18: OAc was added in different ratios to a 100:3 binary mixture ofE,Z2,13–18:OAc/E,Z3,13–18:OAc in Hungary, it strongly reduced captures at, or above a ratio of 10033 but no decrease was recorded at a ratio of 10031. In New Zealand and Tasmania it reduced captures at a ratio of 10031. Observations of behavioral responses of maleS. tipuliformis in Hungary to synthetic baits in the field showed thatE,Z2,13–18:OAcby itself evoked close-range approaches to the source from only 20% of males, whereas the addition ofE,Z3,13–18:OAc in a ratio of 1003 raised that value to 65 %. Landing on the source was significant only at sources with a 10030.1310 blend ofE,Z2,13–18:OAc/E,Z3,13–18: OAc/Z,Z3,13–18: OAc/Z,Z3,13–18: OH/Z13–18: OAc. A 1003 binary mixture ofE,Z2,13–18:OAc/E,Z3,13–18:OAc in a dose range of 10–1000 g can be recommended for more effective field monitoring ofS. tipuliformis populations in Hungary and in New Zealand. In Tasmania, at present,E,Z2,13–18: OAc by itself is the most potent sex attractant of the species.     

Sex pheromone ofAdoxophyes orana: Additional components and variability in ratio of (Z)-9- and (Z)-11-tetradecenyl acetate

Twelve products related to the sex pheromone main components (Z)-9- and (Z)-11-tetradecenyl acetate (Z9–14Ac andZ11–14Ac, respectively), were identified in female pheromone gland extracts of the laboratory-reared summerfruit tortrix moth,Adoxophyes orana F.v R. These are the geometric isomers and the alcohols of the main components, (Z)-9-dodecenyl acetate, (Z)-11-hexadecenyl acetate, and saturated acetates of 12–22 carbons. The ratio ofZ9–14Ac toZ11–14Ac in individuals varied from 3.51 to 111 with an average of 6.2; their total added up to 462 ng/female with an average of 182 ng for 2- to 7-day-old individuals. No qualitative or quantitative differences were observed between laboratory and field insects.Z9–14Ac,Z11–14Ac and the corresponding alcohols were also found in female effluvia. Addition of either of the two alcohols to a blend of the two acetates augmented trap catch in the field. The same was true for (Z)-9,(E)-12-tetradecadienyl acetate which was not detected in gland extracts.     

Apple ermine moth,Yponomeuta malinellus Zeller Two components of female sex pheromone gland highly effective in field trapping tests

When electroantennographic responses of maleYponomeuta malinellus Zeller to model compounds were determined at dosages of 0.3–30 ng, the strongest responses were obtained from (Z)-9-dodecen-1-ol acetate (Z9–12Ac). Also, strong responses were obtained from (Z)-11-tetradecenal (Z11–14A1) and (Z)-11-tetradecen-1-ol (Zl1–14OH). At a dosage of 0.3 ng,Z11–14A1 produced a stronger response thanZ11–14OH, while at a dosage of 30 ng,Z11–14OH andZ11–14A1 produced equal responses. Gas chromatographic and mass spectral analysis of extracts of female sex pheromone glands showed the presence ofZ9–12Ac, tetradecan-1-ol (14OH), (E)-11-tetradecen-1-ol (E11–14OH),Z11–14OH, hexadecan-1-ol, and hexadecan-1-ol acetate in a ratio of 0.62003710014035. In field tests,Z9–12Ac andZ11–14OH together were required for trap catch, and addition ofZ11–14A1,E11–14OH, 14OH, or (Z)-11-tetradecen-1-ol acetate did not increase catch. Ratios in rubber septa of 0.599.5 to 1.598.5 (Z9–12 Ac/Z11–14OH) captured the most males and captures were statistically equivalent for dosages of 10–1000 g/rubber septum. Traps baited with the synthetic lure produced better catches than those baited with females.Lepidoptera: Yponomeutidae.     

Identification of a four-component sex pheromone of the female oriental fruit moth,Grapholitha molesta (Lepidoptera: Tortricidae)

The female-emitted pheromone ofGrapholitha molesta (Busck), the Oriental fruit moth, was collected by holding females in glass flasks during calling. Flask washes were found to contain four pheromone components: (Z)-8-dodecenyl acetate and (E)-8-dodecenyl acetate in a 1007 ratio, and (Z)-8-dodecen-1-ol and dodecanol in a 10020 ratio. The ratio of (Z)-8-acetate to (Z)-8-dodecen-1-ol was approx. 10030. Approximately 0.1–0.2 ng of pheromone was recovered per female per hour of calling.Published as Journal Article No. 8598 of the Michigan State University Agricultural Experiment Station.     

Sex pheromone ofGrapholita funebrana occurrence ofZ-8- andZ-10-Tetradecenyl acetate as secondary components

Z-8-Dodecenyl acetate (Z8–12Ac),E-8-dodecenyl acetate (E8–12Ac),Z-8-tetradecenyl acetate (Z8–14Ac),Z-10-tetradecenyl acetate (Z10–14Ac), andZ-8-dodecen-1-ol (Z8–12OH) were identified in the proportions 10013052 in female sex gland extracts ofGrapholita funebrana, accompanied by saturated acetates from 12 to 20 carbons with tetradecyl acetate predominating.Z10–14Ac has not previously been described as a lepidopteran sex pheromone component. Best attraction of males is obtained withZ8–12Ac in the presence of a higher proportion ofE8–12Ac than in the female. Inclusion of the 14-carbon acetates did not augmentG. funebrana catches but inhibitedG. molesta. On the other hand, addition ofZ8–12OH at the level optimal forG. molesta reduced attraction ofG. funebrana.     

Identification and field testing of female-produced sex pheromone components of the spring cankerworm,Paleacrita vernata Peck (Lepidoptera: Geometridae)

Two sex pheromone components, 3(Z),6(Z),9(Z)-nonadecatriene (3Z,6Z,9Z-19 H), and 3(Z),6(Z),9(Z)-eicosatriene (3Z,6Z,9Z-20 H), have been positively identified, and a third component, 6(Z),9(Z)-nonadecadiene (6(Z),9(Z)-19 H) has been tentatively identified from abdominal tip extracts of female spring cankerworm moths,Paleacrita vernata Peck (Lepidoptera Geometridae). The pheromone components were identified by a combination of gas chromatography, electroantennography, mass spectrometry, chemical tests, comparison with standards, and field testing. Only 3Z,6Z,9Z-20 H exhibited significant attractant activity when tested alone, and it was potentiated by the other two components. The attractive blend was an 821 ratio of 3Z,6Z,9Z-20H/3Z,6Z,9Z-19H/6Z,9Z-19H. However, the two-component blend of 3Z,6Z,9Z-20 H and 6Z,9Z-19 H (81 ratio) was as attractive as the three-component blend in further field tests. A series of related compounds, the diene monoepoxides available from epoxidation of C₁₉ and C₂₀ 3Z,6Z,9Z-trienes, some of which have been found in the pheromone blends of other moth species, were tested as behavioral antagonists. The attraction of male moths to synthetic lures was suppressed by the addition of 6Z,9Z-cis-3,4-epoxy-nonadecadiene to the lures. Additional experiments were performed to determine the effects of lure dosage, trap height, and trap design on the numbers of male moths captured.Issued as NRCC 30711.     

Aggregation pheromone characterization and comparison inDrosophila ananassae andDrosophila bipectinata

(Z)-11-Octadecenyl acetate (Z11–18Ac) and (Z)-11-eicosenyl acetate (Z11–20Ac) were identified as the aggregation pheromones ofDrosophila ananassae, andZ11–20Ac was identified as the aggregation pheromone ofDrosophila bipectinata. Z11–18Ac andZ11–20Ac were not attractive alone; however, in combination with fermenting food odors, the acetates attracted flies of both sexes in a wind-tunnel olfactometer. The pheromones were present in the ejaculatory bulb of sexually mature male flies and transferred to the female during mating. MaleD. bipectinata released little if anyZ11–20Ac to the food; however, recently mated females releasedZ11–20Ac to the surrounding surfaces in just a few hours after mating.D. ananassae males, on the other hand, appeared to release moreZ11–18Ac andZ11–20Ac to the surroundings than mated females. AlthoughD. bipectinata males had noZ11–18Ac, flies were as attracted toZ11–18Ac as to an equal quantity ofZ11–20Ac.D. ananassae were attracted toZ11–18Ac but not toZ11–16Ac orZ11–20Ac. However,Z11–20Ac in combination withZ11–18Ac was significantly more attractive thanZ11–18Ac alone.     

Sex pheromone components of the variegated leafroller moth,Platynota flavedana

Female tip extracts of the variegated leafroller moth,Platynota flavedana (Clemens), were analyzed and found to contain a mixture of (E)-11-tetradecen-1-ol and (Z)-11-tetradecen-1-ol (91), as well as a mixture of (E)-11-tetradecenyl acetate and (Z)-11-tetradecenyl acetate (2-31). Small amounts of tetradecen-1-ol and tetradecyl acetate probably are also present. In the field, a mixture of the two alcohols (8416,EZ ratio) attracted significantly more male moths of this species than any other mixture tested. The data indicate that the acetates are probably not used as pheromone components.Lepidoptera:Tortricidae:Tortricinae.This research was supported in part by the Rockefeller Foundation and by NSF Grant No. GB-38020.     

Components of female sex pheromone of spotted bollworm,Earias vittella F. (Lepidoptera: Noctuidae): Identification and field evaluation in Pakistan

Ovipositor washings from virgin femaleEarias vittella (F.) (Lepidoptera: Noctuidae) moths were examined by gas chromatography (GC) linked to electroantennography (EAG). Six components were detected by the male moth. These were identified by comparison of their retention times with those of a range of synthetic standards on fused silica capillary GC columns as hexadecanal, (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, octadecanal, (Z)-11-octadecenal, and (E,E)-10,12-hexadecadien-1-ol in 1210241 ratio. Field testing in Pakistan showed that a 2102 mixture of (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, and (Z)-11-octadecenal was as attractive to maleE. vittella moths as the six-component mixture and equal in attractiveness to a virgin female moth. Omitting (Z)-11-hexadecenal or (Z)-11-octadecenal greatly reduced this attractiveness. It was found that synthetic lures must be protected from sunlight to prevent loss of attractiveness caused by isomerization of the conjugated diene aldehyde, and addition of (E,Z)-10,12-hexadecadienal, one of the products of isomerization, was shown to reduce attractiveness significantly. During this work, a 101 mixture of (E,E)-10, 12-hexadecadienal and (Z)-11-hexadecenal was shown to be as attractive toE. insulana (Boisd.) male moths as a virgin female moth, and the attractiveness of this mixture was further increased by addition of (E,Z)-10,12-hexadecadienal.     

Sex pheromone of aPlanotortrix excessana sibling species and reinvestigation of related species

The sex pheromone of aPlanotortrix excessana sibling species was investigated. Females were found to produce eight potential pheromone components: dodecyl acetate, tetradecyl acetate (14OAc). (Z)-5-tetradecenyl acetate (Z5-14OAc), (Z)-7-tetradecenyl acetate (Z7-14OAc), (Z)-9-tetradecenyl acetate, hexadecyl acetate, (Z)-7-hexadecenyl acetate, and (Z)-9-hexadecenyl acetate. When these compounds were bioassayed using field-trapping and wind-tunnel techniques, only 14OAc,Z5-14OAc, andZ7-14OAc were found to be behaviorally active. The sex pheromone glands of females of other species including,Planotortrix MBS,Planotortrix M,P. notophaea, Ctenopseustis servana, and aC. obliquana sibling species, were also found to containZ5-14OAc orZ7-14OAc, singly or in combination. In the case ofPlanotortrix M, the addition ofZ7-14OAc to the previously identified sex pheromone blend ofZ5-14OAc and 14OAc was found to increase trap captures of male moths of this species. Thus in these New Zealand species (and in some Australian species),Z5-14OAc andZ7-14OAc appear to be utilized in combination in pheromonal communication just as (Z)-11-tetradecenyl acetate and (E)-11-tetradecenyl acetate are used by many species of Holarctic Tortricidae in the tribe Archipini.Lepidoptera: Tortricidae: Tortricinae.     

Identification of sex pheromone of calendula plume mothPlatyptilia williamsii

The sex pheromone of the calendula plume moth,Platyptilia williamsii was identified as (Z)-11-hexadecenal (Z11–16Aid). Extracts of female sex pheromone glands contained several compounds when analyzed by capillary and packed-column GLC. However, airborne collections of volatiles from glands contained only one of these compounds, having the same retention time asZ11–16Ald. GC-MS and microozonolysis analyses of the natural product were consistent with those of syntheticZ11–16Ald. In a flight tunnel, males oriented upwind and touched sources ofZ11–16Ald and gland extract with equal frequency. Field tests of syntheticZ11–16Ald already have shown it to be a potent sex attractant for males of this species. This study further supports the hypothesis thatP. williamsii and a sympatric species,Platyptilia carduidactyla, are not reproductively isolated by chemical differences in the composition of the sex pheromone, but rather by temporal differences in sexual activities.     

Intraspecific variation and interspecific differences in sex pheromones of sibling species inCtenopseustis obliquana complex

The specific status ofCtenopseustis obliquana pheromone-types I, II, and III has been more fully examined. Females of types I and III produce a mixture of (Z)-8- and (Z)-5-tetradecenyl acetates (Z8-14:Ac, Z5-14: Ac). The previously reported different ratios of these two components in females of the two types (type I=8020, III=9010) have been reinvestigated. The median ratios of each type differed significantly, although there was some overlap in the ranges of these ratios. A field cage trial showed that males of type III are attracted to females of type I, so the observed differences may be ascribed to intraspecific variation. In contrast to females of types I or III, females of type II produce Z5-14Ac but no Z8-14Ac. The electroantennogram (EAG) profile of antennae of type II males shows a maximum response to Z5-14Ac, while the EAG profiles of types I and III show a strong response to Z8-14Ac. In wind tunnel tests using mixtures of these two compounds, type II males prefer blends consisting of all or mostly Z5-14: Ac, while type I males showed a preference to a mix of 70% Z8-14Ac plus 30% Z5-14Ac. We found that type I males are attracted to type I females when offered a choice between type I and type II females in a field cage test and that type II males similarly prefer type II females. Males of types I and II have specialist cells for Z8-14Ac and Z5-14Ac but differ with respect to relative densities of these cells and to further cell types responsive to other alkenyl acetates. Type IIC. obliquana is considered therefore a sibling species of types I and III. In addition, the amount of Z5-14Ac produced by type II females varied geographically. Females from the North Island produced significantly less (median=1.2 ng) Z5-14Ac than females from the South Island (median=2.2 ng). Type II populations in the North Island morphologically resembled sympatric type I, rather than type II from the South Island and are designated as type II (North Island). Type II (North Island) populations have so far been found only at Rukuhia (near Hamilton) and from Kerikeri. In contrast, type II populations are sympatric with type III populations over much of the South Island. In a field cage trial, males of types II and II (North Island) were attracted to females of both II and II (North Island). We tentatively ascribe the differences between type II and type II (North Island) to intraspecific variation.     

Sex pheromone of the armyworm,Pseudaletia unipuncta (Haworth) (Lepidoptera: Noctuidae)

(Z)-11-Hexadecen-1-ol acetate (Z11–16Ac) free of theE isomer (<1%), hexadecan-1-ol acetate (16 Ac), and a hexadecen-1-ol [the (Z)-11 isomer based on the retention time on a Carbowax capillary column] were identified in extracts of the sex pheromone glands of adult virgin female armyworms,Pseudaletia unipuncta. Also, gas Chromatographic retention times on polar and nonpolar columns indicated the possible presence of (Z)-9-hexadecen-1-ol acetate (Z9–16Ac). The ratioZ11–16Ac/16Ac/Z11–16OH/Z9–16Ac was 10.150.130.02. Infield testsZ11–16 Ac was attractive alone, and the addition ofZ9–16Ac,Zll–16 OH, or 16 Ac singly or in combination in ratios found in the gland did not increase trap capture.Mention of a proprietary product does not constitute an endorsement of this product by the USDA.     

A four-component pheromone blend for optimum attraction of redbacked cutworm males,Euxoa ochrogaster (Guenée)

Four acetates,Z-5-decenyl acetate,Z-5-,Z-7-, andZ-9-dodecenyl acetates, in microgram ratios of 120021 or 120062 were excellent, specific sex pheromone blends for capturing male redbacked cutworm moths in cone traps. Blends in ratios of 120021 and 220021 at 1000 g/ rubber septum dispenser remained highly effective for 6 weeks under field conditions. The essential minor components,Z-5-decenyl,Z-7-, andZ-9-dodecenyl acetates, became inhibitory at concentrations of about 10% in the blends, and this may be an important general phenomenon in lepidopteran pheromones. Blends involving a parapheromone,Z-5-undecenyl acetate, withZ-5-,Z-7-, andZ-9-dodecenyl acetate, in microgram ratios of 820021 or 2020062 were also excellent specific attractants for this species. TheZ-8-dodecenyl acetate had no obvious effect on the attraction of the redbacked cutworm males.     

Individual variation in sex pheromone of smaller tea tortrix moth,Adoxophyes sp. (Lepidoptera: Tortricidae)

Female smaller tea tortrix mothsAdoxophyes sp. (Lepidoptera: Tortricidae), which initiated calling at 1, 2, or 3 days old, respectively, were analyzed individually for (Z)-11-tetradecenyl acetate (Z11-14:OAc) and (Z)-9-tetradecenyl acetate (Z9–14: OAc) in the pheromone gland via GLC. Among different age groups, broad and similar distributions were found for pheromone quantity (¯X=58.6±52.9 ng/female; range 1.3–219.8 ng/female). The ratio of the two pheromone components averaged 6535 but ranged from 8416 to 4060. The significance of the pheromone blend variation to the attraction of males was tested in a field experiment. The ratio of males trapped by the most attractive blend versus the least attractive one was 2.2.     

Pheromone variation among eastern European and a western Asian population of the turnip mothAgrotis segetum

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 15247 and 14257 for the respective populations. Corresponding male receptor frequencies were 9901 and 6922. 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.Schiff. (Lepidoptera: Noctuidae).