Sex pheromone components of fall cankerworm moth,Alsophila pometaria

(Z,Z,Z,E)-3,6,9,11-Nonadecatetraene and (Z,Z,Z,Z)-3,6,9,11-nonadecatetraene, sex pheromone components ofAlsophila pometaria, were synthesized by stereoselective Wittig reactions and found to be spectroscopically and chromatographically identical to isolated natural material. Flight-tunnel bioassays and field-trapping experiments confirmed that the two tetraenes together with (Z,Z,Z)-3,6,9-nonadecatriene are sex pheromone components. While traps baited with either tetraene individually captured conspecific males in field-trapping experiments, addition of the triene, which captured no males by itself, to either tetraene resulted in synergistic responses.Lepidoptera: Geometridae.Issued as NRCC No. 23462.     

Novel sex pheromone components from the fall cankerworm moth,Alsophila pometaria

A sex pheromone extract from fall cankerworm moths,Alsophila pometaria, attracted conspecific males in field tests. Four EAG-active components were isolated from the extract and identified by GC-MS, highfield PMR spectroscopy, and microchemical techniques asn-nonadecane (I), (Z,Z,Z)-3,6,9-nonadecatriene (II), (Z,Z,Z,E)-3,6,9,11-nonadecatetraene (III), and (Z,Z,Z,Z)-3,6,9,11-nonadecatetrane (IV). Studies of the behavioral responses of male moths in a flight tunnel to the isolated components showed II, III, and IV were the major components of the sex pheromone. No sex pheromone behavioral responses were observed for I.Lepidoptera: Geometridae.issued as NRCC No. 22964.     

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.     

Sabulodes caberata guenée (Lepidoptera: Geometridae)

A 6,9-nonadecadiene, (Z)-9-nonadecene, andn-nonadecane were identified in extracts of sex pheromone glands of femaleSabulodes caberata Guenée. Potential pheromonal activity of gland components was assessed by electroantennogram measurements of gas-chromatographic fractions of abdominal tip extracts. Chemical identification was based on gas chromatography and mass spectrometry of parent compounds, hydrogenation products, ozonolysis products, dimethyl disulfide adducts, and synthesis. The monoene was synthesized via coupling of alkyl and acetylenic intermediates. (Z,Z)-6,9-Nonadecadiene (Z6,Z9-19H) was synthesized from methyl linoleate via chain lengthening. SyntheticZ6,Z9-19H had the same retention times on polar and nonpolar capillary gas-chromatographic columns as the 6,9-nonadecadiene from the sex pheromone glands. In field testsZ6,Z9-19:H alone produced trap catch of maleS. caberata and addition of (Z)-9-nonadecene orn-nonadecane had no effect on trap catch.This paper reports the results of research only. Mention of a commercial product in this paper does not constitute a recommendation by the U.S. Department of Agriculture.     

Sex pheromone of the western hemlock looper,Lambdina fiscellaria lugubrosa (Hulst) (Lepidoptera: Geometridae)

The sex pheromone of the western hemlock looper (WHL),Lambdina fiscellaria lugubrosa (Hulst), comprises three methylated hydrocarbons: 5,11-dimethylheptadecane (5,11), 2,5-dimethylheptadecane (2,5), and 7-methylheptadecane (7). Compounds extracted from female pheromone glands were identified by coupled gas chromatographic-electroantennographic (GC-EAD) analysis and coupled GC-mass spectroscopy in selected ion monitoring mode. In trapping experiments, (5,11) alone attracted male moths, but addition of either (7) or (2,5) significantly enhanced attraction. (5,11) combined with both (7) and (2,5) was significantly most attractive. (5,11) and (2,5) are also sex pheromone components of the eastern hemlock looper (EHL),Lambdina fiscellaria fiscellaria (Guen.). Although (7) is produced by the EHL, it is a pheromone component only in the WHL. It constitutes the first behaviorally active monomethyl-branched hydrocarbon to be found in a geometrid and is a novel lepidopteran sex pheromone component. The different 2- versus 3-component sex pheromone supports taxonomic division of EHL and WHL.     

Sex pheromone components of the spring hemlock looper,Lambdina athasaria (Walker) (Lepidoptera: Geometridae)

Two methylated hydrocarbons, 7-methylheptadecane (7) and 7,11-dimethylheptadecane (7,11), are female sex pheromone components of the spring hemlock looper (SHL),Lambdina athasaria (Walker). Compounds extracted from female pheromone glands were identified by coupled gas chromatographic-electroantennographic detection (GC-EAD) and coupled GC-mass spectrometry (GC-MS) in selected ion monitoring mode. In field trapping experiments, (7) and (7,11) by themselves were behaviorally inactive, but in combination attracted numerous male moths. (5,11)-Dimethylheptadecane (5,11) was detected in female SHL pheromone gland extracts, but did not enhance attraction to the binary blend of (7) and (7,11). The sex pheromone of SHL is related to that of congeneric eastern hemlock looper (EHL),Lambdina fiscellaria fiscellaria (Guen.) [(5,11) and 2,5-dimethylheptadecane (2,5)] and western hemlock looper (WHL),L.f. lugubrosa (Hulst) [(5,11), (2,5) and (7)]. Specificity of the pheromonal blend, spatial separation of coseasonal EHL and WHL, and temporal separation of sympatric EHL and SHL contribute to reproductive isolation.Dedicated to my father, Johannes Dinter, in honor of his 73th birthday.     

Electrophysiological and chemical analysis of sex pheromone communication system of the mottled umber,Erannis defoliaria (Lepidoptera: Geometridae)

(Z,Z,Z)-3,6,9-nonadecatriene (Z3,Z6,Z9–19Hy) and (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3,Z9-cis-6,7-epo-19Hy) were identified in pheromone gland extracts from femaleErannis defoliaria. The two components were found in a 13 ratio, with the main component,Z3,Z9-cis-6,7-epo-19Hy present at an amount of about 1.5 ng per female. The components were identified by means of gas chromatography-mass spectrometry, gas chromatography-electroantennography and gas chromatography-single sensillum recordings. Single sensillum measurements on the male antenna showed two physiological types of sensilla. One type was characterized by a large spike amplitude cell responding toZ3,Z9-cis-6,7-epoxy-19Hy and a small spike amplitude cell responding toZ3,Z6,Z9–19Hy. A second type responded only with a large spike amplitude cell to the epoxide, and this cell was inhibited by the triene. Of the two pheromone components, the epoxide gave the higher response in the EAG tests. Preliminary field tests support the identification of the pheromone components. The epoxide was also found to be present in the extract of the pheromone gland ofColotois pennaria, and males ofC. pennaria andAgriopis marginaria were trapped by the mixture of the identified compounds.     

Sex pheromone components of the giant looper,Boarmia selenaria schiff. (Lepidoptera: Geometridae): Identification,synthesis, electrophysiological evaluation,and behavioral activity

(Z,Z)-6,9-cis-(3S,4R)-Epoxynonadecadiene9a and (Z,Z,Z)-3,6,9-nonadecatriene have been identified as sex pheromone components in female ovipositor extracts and effluvia of the geometridBoarmia selenaria. The identification was based on relative retention times on gas chromatographic columns, GC-MS, chemical enantioselective syntheses, EAG, wind-tunnel behavioral experiments, and field tests. A single female ovipositor extract contained an average of 42 ng of (Z,Z)-6,9-cis-3,4-epoxynonadecadiene and 2 ng of (Z,Z,Z)-3,6,9-nonadecatriene.EAG, wind-tunnel behavioral studies, and field tests demonstrated that maleB. selenaria exhibit preferential attraction for the (3S,4R)-enantiomer of (Z,Z)-6,9-cis-3,4-epoxynonadecadiene. Only in effluvia and ovipositor extracts of calling females was (Z,Z)-6,9-cis- 3,4-epoxynonadecadiene detected, whereas relatively high amounts of (Z,Z,Z)-3,6,9-nonadecatriene were found in noncalling females. Wind-tunnel behavioral studies showed that (Z,Z,Z)-3,6,9-nonadecatriene did not elicit any response in the males, and when tested in combination with a mixture of monoepoxynonadecadienes, (Z,Z,Z)-3,6,9-nonadecatriene decreased the observed behavioral responses. A possible precursor role for (Z,Z,Z)-3,6,9-nonadecatriene in the pheromonal system is discussed.     

Quantitative and qualitative variation in male pheromones ofPhragmatobia fuliginosa andPyrrharctia isabella (Lepidoptera: Arctiidae)

The dihydropyrrolizine pheromones, hydroxydanaidal and danaidal, were identified from the scent organs of malePhragmatobia fuliginosa (L.) andPyrrharctia isabella (J.E. Smith). Qualitative and quantitative GLC analyses were conducted on ca. 80 field-collected males of each species. The total pheromone titer was distributed bimodally in each species with most males having either a small amount (< 10 ng) of pheromone or a large amount (1–10 g inPyrrharctia and 0.3–3 g inPhragmatobia).Pyrrharctia males in the 1- to 10-g range had a predominance of hydroxydanaidal, with little if any danaidal. MostPhragmatobia males in the 0.3- to 3-g range had danaidal with little if any hydroxydanaidal. These compounds elicited a courtship response in sexually receptive females of both species. A bioassay based on this response was used to measure the thresholds of female response to these compounds.Pyrrharctia females were more sensitive to (R)-(–)-hydroxydanaidal than to danaidal.Phragmatobia females were more sensitive to danaidal then to (R)-(–)-hydroxydanaidal.     

(6Z,9Z-3R,4S)-Epoxy-heptadecadiene: major sex pheromone component of the larch looper,Semiothisa sexmaculata (Packard) (Lepidoptera: Geometridae)

Gas chromatographic-electroantennographic analysis (GC-EAD) of female larch looper,Semiothisa sexmaculata (Packard), gland extracts revealed two EAD-active compounds. Retention index calculations, GC-mass spectroscopy in selected ion monitoring mode, and GC-EAD analysis of authentic standards identified the compounds as (3Z,6Z,9Z)-heptadecatriene (3Z,6Z,9Z-17H) and (6Z,9Z)-cis-3,4-epoxy-heptadecadiene (6Z,9Z-cis-3,4-epoxy-17H). Chirality determination of the monoepoxydiene in gland extracts was impeded by small quantities, but field experiments indicated that maleS. sexmaculata were most strongly attracted to enantiomerically enriched 6Z,9Z-3R,4S-epoxy-17H (69% ee), while maleS. neptaria (Guenée) responded well to various blends of theR,S- and S,R-epoxide enantiomers. Binary combinations of theR,S-epoxide enantiomer with 3Z,6Z,9Z-17H significantly inhibited response by maleS. sexmaculata, but strongly enhanced attraction of sympatric maleS. marmorata Ferguson. Enantiomerically enriched 6Z,9Z-3R,4S-epoxy-17H can be used as a trap bait to monitor populations of the larch-defoliatingS. sexmaculata. Whether 6Z,9Z-3R,4S-epoxy-17H serves as single component sex pheromone inS. sexmaculata or small amounts of 6Z,9Z-3S,4R-epoxy-17H synergize or suppress optimal attraction, will be tested as chirally pure monoepoxydienes become available.     

Sex pheromone of lucerne leafroller,Merophyas divulsana (Walker) (Lepidoptera: Tortricidae): Evidence for two distinct populations

When specimens of the lucerne leafroller,Merophyas divulsana, were sampled from an area with a history of crop damage, they were found to have (E)-11-tetradecenyl acetate, hexadecyl acetate, and tetradecyl acetate as principal components of the pheromone gland. A synthetic mixture of these compounds proved to be a successful lure in delta traps. On the other hand, apparently identical moths collected in areas with no history of crop damage were found to have (Z)-11-tetradecenyl acetate as the major component of the sex pheromone gland. The distribution of the two moths provides the basis for a plausible explanation of the regional pest activity reported forM. divulsana.     

Chirality of 5,11-dimethylheptadecane,the major sex pheromone component of the hemlock looper,Lambdina fiscellaria (Lepidoptera: Geometridae)

Of the four possible stereoisomers of 5,11-dimethylheptadecane, the major sex pheromone component of the eastern hemlock looper (EHL),Lambdina fiscellaria fiscellaria Guen., and the western hemlock looper (WHL),Lambdina fiscellaria lugubrosa Hulst, (5R,11S)-5,11-dimethylheptadecane was the only stereoisomer eliciting electrophysiological responses by male EHL and WHL antennae. In field bioassays with EHL and WHL populations, traps baited with (5R,11S)-5, 11-dimethylheptadecane caught as many males as did traps baited with all four stereoisomers combined or a synthetic mixture of 5,11-dimethylheptadecanes. Catches in traps baited with the other three stereoisomers did not significantly differ from those in the unbaited control traps. We conclude that male antennae lack chemoreceptors for the other three stereoisomers of 5,11-dimethylheptadecane and hypothesize that only (5R,115)-5,11-dimethylheptadecane is produced by female EHLs and WHLs.     

Biological amplification for increasing electroantennogram discrimination between two female sex pheromones ofSpodoptera littoralis (Lepidoptera: Noctuidae)

MaleSpodoptera littoralis stimulated by a mixture ofS. littoralis female sex pheromone with a positional isomer and by the pheromone alone, gave greatly amplified electroantennograms (EAGs) when the antennae were connected in series. The technique is described and examples are given of its use in screening extracts for EAG activity. Dose-response curves obtained with this technique are presented and discussed. Through biological amplification, EAG discrimination between the pheromones was increased.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, No. 238-E, 1980 series.     

3,13-Dimethylheptadecane: Major sex pheromone component of the western false hemlock looper,Nepytia freemani Munroe (Lepidoptera: Geometridae)

3,13-Dimethylheptadecane (3,13-dime-17Hy) is the major sex pheromone component of the western false hemlock looper (WFHL),Nepytia freemani Munroe. It was identified in extracts of female pheromone glands by coupled gas chromatographic-electroantennographic detection (GC-EAD) and coupled GC-mass spectroscopy (GC-MS). Traps baited with 100g of 3,13-dime-17Hy attracted large numbers of male WFHL. Of five additional candidate pheromone dimethylated hydrocarbons, only 3,13-dimethylhexadecane attracted male WFHL. However, neither 3,13-dime-16Hy nor the other four compounds enhanced attraction to 3,13-dime-17Hy when tested in binary or ternary combination at respective ratios of 10010, 1001, or 10011. Identification of the complete WFHL sex pheromone requires structural elucidation of all 12 EAD-active components in gland extracts, determination of their chirality, and field testing of antennally active isomers in appropriate combinations and ratios. Stereoisomeric 3,13-dime-17Hy as trap bait may already be used to monitor WFHL populations.     

Influence of pheromone trap color and design on capture of male velvetbean caterpillar and fall armyworm moths (Lepidoptera: Noctuidae)

Three pheromone traps were evaluated in paired field trials for effectiveness in capturing wild male velvetbean caterpillar moths (VBC),Anticarsia gemmatalis Hübner, and fall armyworm moths (FAW),Spodoptera frugiperda (J.E. Smith), using a wind-oriented trapping device. The traps were: (1) the standard multicolored bucket trap consisting of a forest green canopy, yellow funnel, white bucket and open (i.e., single wire) pheromone holder; (2) a forest green monocolored bucket trap; and (3) the Multi-Pher-1 trap consisting of a blue-green canopy, white funnel, white bucket, and white, multislotted pheromone holder. The Multi-Pher-1 trap differs primarily from the other two in that its entrance is smaller in diameter and is partially obstructed by the pheromone holder. Significantly fewer VBC and FAW males were captured in pheromone-baited monocolored (forest green) bucket traps than standard multicolored bucket traps. The Multi-Pher-1 trap also caught significantly fewer VBC moths than the standard multicolored bucket trap, but there was no significant difference in numbers of FAW moths caught in the two traps. The results further demonstrate the importance of considering visual cues, in this case color, in the design of pheromone traps for nocturnal insects.This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or the recommendation for its use by USDA.     

Pheromone differences between sibling taxaDiachrysia chrysitis (linnaeus, 1758) andD. tutti (Kostrowicki, 1961) (Lepidoptera: Noctuidae)

The noctuid sibling taxaDiachrysia chrysitis s. str. andD. tutti, of yet uncertain taxonomic status, have previously been shown to possess differences in morphology and to be attracted to different mixtures of the two presumed pheromone components (Z)-5-decenyl acetate and (Z)-7-decenyl acetate. TypicalD. tutti males (clearly broken forewing marking) are known to respond to a 2: 100 mixture of the two isomers, whereasD. chrysitis males (unbroken marking) are attracted to a 100: 10 mixture. We investigated female pheromone production and male electroantennographic (EAG) response inDiachrysia families raised in the laboratory from field-collected gravid females. Extracts of individual females from typicalD. tutti andD. chrysitis families were subjected to gas chromatography with simultaneous flame ionization and electroantennographic detection. All females produced mixtures of Z5- and Z7-10:OAc, but femaleD. chrysitis produced predominantly Z5-10:OAc and the antennae of their brothers responded more strongly to the Z5 peak than to the Z7-10:OAc peak, whereas the opposite was true forD. tutti families. The pheromone components were shown to be biosynthesized from hexadecanoic and tetradecanoic acid, respectively by Z11-desaturation followed by chain shortening, reduction, and acetylation. The EAG responses of males trapped with the typicalD. tutti andD. chrysitis blends, as well as with an intermediate blend, were investigated. Males trapped with theD. tutti mixture almost exclusively had a clearly broken wing marking and showed strongest EAG response to Z7-10:OAc. The intermediate blend and theD. chrysitis mixture gave more mixed catches, but with a prevalence of males with an unbroken (or almost unbroken) wing marking and with a higher mean response to Z5-10:OAc. Some males with typicalD. tutti EAG responses were attracted in the field to theD. chrysitis pheromone. In the flight tunnel someD. chrysitis males were attracted also to theD. tutti mixture. This indicates that cross attraction may take place between the two taxa under natural conditions.     

Abraxas grossulariata L. (Lepidoptera: Geometridae): Identification of (3Z,6Z,9Z)-3,6,9-heptadecatriene and (6Z,9Z)-6,9-cis-3,4-epoxyheptadecadiene in the female sex pheromone

(3Z,6Z,9Z)-3,6,9-Heptadecatriene and (6Z,9Z)-6,9-cis-3,4-epoxyheptadecadiene have been identified in female sex pheromone gland extracts ofAbraxas grossulariata L. (Lepidoptera: Geometridae). The compounds were detected by gas chromatography with electroantennographic detection (GC-EAD) and identified by GC-mass spectrometry (GC-MS). The amounts of hydrocarbon and epoxide were 0.13 and 0.42 ng/female, respectively. These identifications were confirmed by synthesis; the absolute configuration of the epoxide remains to be determined. Another isomeric epoxide, (3Z,6Z)-3,6-cis-9,10-epoxyheptadecadiene, was tentatively identified in small amounts (0.04 ng/female). Racemic (6Z,9Z)-6,9-cis-3,4-epoxyheptadecadiene elicited the largest electroantennogram response within a series of heptadecadiene and nonadecadiene monoepoxides and the corresponding trienic hydrocarbons and, in field tests, attracted maleA. grossulariata into traps. Addition of 10% (3Z,6Z,9Z)-3,6,9-heptadecatriene to this epoxide enhanced attractiveness; addition of (3Z,6Z)-3,6-cis-9,10-epoxyheptadecadiene had no effect at low proportions while higher proportions caused a reduction in the numbers of males caught.     

Sex pheromone of tobacco stem borer,Scrobipalpa heliopa (Lower) (Lepidoptera: Gelechiidae)

The major volatile component in the extract of the female sex pheromone gland ofScrobipalpa heliopa was shown to be (E)-3-tridecen-1-ol acetate (V). The identification was based on mass spectral analyses, comparison of retention times with those of synthetic compounds on polar, nonpolar, and liquid crystal gas chromatographic columns and microchemical studies. The latter included hydrolysis and reacetylation, and mass spectral studies of the derivatives formed by epoxidation and methoxymercuration-demercuration. Analysis of gland extracts by gas chromatography linked to electroantennography showed this component to be the only one with significant biological activity, similar to that of the synthetic compound. (E)-3-Tridecenyl acetate (V) attracted male moths to traps in the field while addition of theZ isomer (III) reduced the numbers of moths caught.     

Evidence for presence and nature of female sex pheromone ofBrithys crini fabricius (Lepidoptera: Noctuidae)

The existence of a female sex pheromone of the noctuid mothBrithys crini Fabricius was confirmed in both laboratory bioassay and field tests. Crude extracts and airborne volatiles from females were analyzed by gas chromatography and mass spectrometry and the data compared with authentic compounds. The primary sex pheromonal compound was Z11-16: Ald. Scanning electron microscopy showed that the external surface of the sex pheromone gland was covered with folds that might increase the sex pheromone evaporation area.     

(E)-11,13-tetradecadienal: Major sex pheromone component of the eastern blackheaded budworm,Acleris variana (Fern.) (Lepidoptera: Tortricidae)

(E)-11,13-Tetradecadienal (E11,13–14:Ald) is the major sex pheromone component of the eastern blackheaded budworm (EBB),Acleris variana (Fern.). The compound was identified in female pheromone gland extracts by coupled gas chromatographic-electroantennographic detection (GC-EAD), coupled GC-mass spectrometry in selected ion monitoring mode, and retention index calculations of candidate pheromone components.E11,13–14:Ald alone as trap bait was very attractive to male EBB. Addition of the corresponding diene alcohol or acetate or both did not enhance attraction. (Z)-11,13-Tetradecadienal in binary combination with (E)-11,13–14:Ald neither enhanced nor reduced trap catches. Increasing the amounts of pheromone from 0.01 to 10 µg increased trap catches, but increase of pheromone quantity above 100 µg proportionately reduced attraction. Stabilization of slowly polymerizingE11,13–14:Ald and development of a sustained, adequate release rate is required for pheromone-based monitoring of EBB populations.