Chemical and behavioral studies on dufour gland contents ofManica rubida (Hymenoptera: Formicidae)

The Dufour gland ofManica rubida contains a simple mixture of (Z, E)-α-farnesene and (Z, E)-α-homofarnesene with tiny amounts of other faraesene, homofarnesene, and bishomofarnesene isomers. The gland also contains a mixture of very volatile compounds, chiefly acetone, with smaller amounts of acetaldehyde, ethanol, propanol, isobutyraldehyde, butenone, and butanone. The workers ofM. rubida are not attracted to these highly volatile compounds as are workers ofMyrmica species, butM. rubida workers show a strong increase of linear speed when stimulated by a freshly isolated gland. This response of increased speed of bothM. rubida andM. trubra to their own or each other's Dufour gland secretion is consistent with the presence of the farnesenes in them both.     

Field trapping of diamondback mothPlutella xylostella using an improved four-component sex attractant blend

In addition to three known sex lure components [(Z)-11-hexadecenyl acetate, (Z)-11-hexadecenal, and (Z)-11-hexadecenol], (Z)-9-tetradecenyl acetate was field-proven as a trace coattractant for malePlutella xylostella, with an optimal content below 0.01% in blends. This potent four-component lure for diamondback males also attractedCrymodes devastator males, and in this respect is not different in its attractancy from virgin diamondback females. Replacement of (Z)-9-tetradecenyl acetate in the four component lure with (Z)-9-tetradecen-1-ol, at the level of 10% of the total lure mixture, did not alter its attractancy for diamondback males, but it did inhibit attraction ofCrymodes devastator. The status of biologically active components as possible sex pheromones or para-pheromones is discussed.     

Sex pheromones and reproductive isolation in four european small ermine moths

Reproductive isolation among four sympatric small ermine moths (Yponomeuta) is analyzed in terms of niches in the sexual communication channel. Potential pheromone components were identified from pheromone gland secretions ofY. evonymellus,Y. cagnagellus,Y. padelius, andY. vigintipunctatus by gas chromatography with flame ionization and electroantennographic detection and tested for behavioral activity in the field. The species were found to share (Z)-11-tetradecenyl acetate (Z11-14: OAc) in combination with varying proportions of theE isomer as primary sex pheromone components.Y. cagnagellus differs from the rest of the species by having only a small amount (1.5%) ofE isomer relative toZ isomer in its pheromone. The closely relatedY. padelius has a three-component pheromone including large amounts (ca. 400%) of (Z)-11-hexadecenyl acetate (Z11–16:OAc) in addition toZ11–14: OAc (100%) andE11–14: OAc (34%).Z11–16: OAc appears to reduce trap catches ofY. evonymellus andY. vigintipunctatus when added to the pheromone. Although these species are the two most distantly related European small ermine moths, they seem to share the same sex pheromone, i.e.,Z11–14OAc (+20%E) and (Z)-11-tetradecenol. Our interpretation is that this might have been the sex pheromone of the ancestor of today'sYponomeuta species.1 Lepidoptera: Yponomeutidae Latr.     

Identification of Sex Pheromone of Adzuki Bean Borer,Ostrinia scapulalis

By means of gas chromatography with electroantennographic detection (GC-EAD), gas chromatography–mass spectrometry (GC-MS), and a series of bioassays, (Z)-11-tetradecenyl acetate (Z11–14:OAc) and (E)-11-tetradecenyl acetate (E11–14:OAc) at a ratio of 100:3 were identified as the female sex pheromone of the adzuki bean borer,Ostrinia scapulalis. The average amounts ofZ11–14: OAc andE11–14:OAc in a single sex pheromone gland were 6.6 ± 2.4 ng and 0.2 ± 0.1 ng, respectively. In a wind-tunnel bioassay, the binary blend ofZ11- andE11–14:OAc elicited almost the same male behavioral responses as did virgin females and sex pheromone gland extract. In field trapping experiments, rubber septa impregnated with the binary blend (50 g/septum) attracted more males than virgin females. The sex pheromone ofO. scapulalis thus turned out to be similar to that of theZ-type European corn borer,O. nubilalis, in both components and their ratio.     

Olefinic acetates, Δ-9,11–14: OAc and Δ-7,9–12: OAc used as sex pheromone components in three geometrid moths,Idaea aversata,I. straminata,andI. biselata (Geometridae,Lepidoptera)

Pheromone compounds so far identified from most geometrid moths consist of all-Z diene, triene, or tetraene hydrocarbons with chain lengths of C₁₇ to C₂₁, and their monoepoxide derivatives biosynthesized from linoleic and linolenic acids. The present study reports the occurrence of olefinic acetates as sex pheromones in three species of Geometridae. (Z,Z)-9,11-tetradecadienyl acetate and (Z,Z)-7,9-dodecadienyl acetate found in female gland extracts ofIdaea aversata elicited significant responses from conspecific male antennae in gas chromatography with electroantennographic detection (GCEAD). In extracts ofI. straminata, (Z,Z)-7,9-dodecadienyl acetate, (E,Z)-7,9-dodecadienyl acetate, and (Z,Z)-7,9-dodecadienyl acetate were found, and the synthetic compounds elicited strong responses from conspecific male antennae. In the third species,I. biselata, only (Z,Z)-7,9-dodecadienyl acetate was found in the female extracts, and this compound elicited a strong EAD response from the conspecific male antenna. The identities of the pheromone components inI. aversata andI. straminata were further confirmed according to their characteristic ions after GC-MS analyses. Single sensillum recordings fromI. aversata showed two types of pheromone-detecting sensilla present on the male antenna. One type contained two receptor neurons, one of which was specifically tuned to (Z,Z)-9,11-tetradecadienyl acetate, the other to (Z,E)-9,11-tetradecadienyl acetate. A second type contained one neuron responding to (Z,Z)-7,9-dodecadienyl acetate. The two types were clearly different also with respect to external morphology, the former being considerably longer and having a larger base diameter. Also inI. straminata two physiological types of sensilla could be distinguished. One type contained two neurons, one of which responded to (Z,Z)-7,9-dodecadienyl acetate, the other to (Z,E)-9,11-tetradecadienyl acetate. The second type contained one neuron, responding to (Z,Z)-7,9-dodecadienyl acetate. No correlation between external morphology and physiological response of the investigated sensilla was observed inI. straminata. In field tests, a two-component blend containing (Z,Z)-9,11-tetradecadienyl acetate and (Z,Z)-7,9-dodecadienyl acetate in a ratio of 10:1 was attractive to males ofI. aversata. This two-component blend was also attractive to males ofI. straminata, but in a ratio of 1:1. High numbers of maleI. biselata were caught in traps baited with (Z,Z)-7,9-dodecadienyl acetate alone. The incorporation of deuterium labels into pheromone components after topical application of deuterium-labeled palmitic acid confirmed that the pheromone components ofI. aversata could be synthesized from this precursor, as has been previously observed for acetate pheromone components of many other moth species. Our results suggest that an evolutionary reversal back to the production of palmitic acid-derived pheromone components has occurred within the geometrid subfamily Sterrhinae.     

Repeatability of pheromone emissions from individual female ermine mothsYponomeuta padellus andYponomeuta rorellus

The repeatability of the composition of pheromone emitted by individual female moths (Yponomeuta) was determined by gas Chromatographic analysis. An improved technique for repeated collections of airborne volatiles from the same moth was developed. The procedure did not harm the females and allowed precise quantification of 0.05 ng of pheromone components in 30-min collections. Individual females ofY. padellus (N=10) andY. rorellus (N=5) were sampled six and eight days after emergence.Y. padellus released, on average, 4.8 ng/30 min of tetradecyl acetate, (E)-11-tetradecenyl acetate, (Z)-11-tetradecenyl acetate, hexadecyl acetate, (Z)-9-hexadecenyl acetate, and (Z)-11-hexadecenyl acetate in the average ratio 4453810049435421. The amount of (E)-11-tetradecenyl acetate relative to (Z)-11-tetradecenyl acetate was less variable [coefficient of variation (CV)=15%] than the relative amounts of the other components (CV=46–61%). The repeatability of the relative amounts of compounds released by individual females was high for all components (r=0.82-0.90). The average emission of tetradecyl acetate, tetradecanol, hexadecyl acetate, and hexadecanol byY. rorellus was 8.3 ng/30 min (ratio 1008102). The repeatability was low for tetradecanol (r=0.51) but higher for hexadecyl acetate (r=0.87) and hexadecanol (r=0.89). The low interindividual variance for the (E)-11-/(Z)-11-tetradecenyl acetate ratio inY. padellus might be due to its importance for reproductive isolation, i.e., it is under strong selection pressure.Lepidoptera: Yponomeutidae Latr.     

Technique for injecting intact glands for analysis of sex pheromones of Lepidoptera by capillary gas chromatography

The structure elucidation of sex pheromones of Lepidoptera by a solid-sample injection technique in conjunction with capillary gas chromatography is described. The applicability of this method in GC and GC-MS modes was demonstrated by reanalyzing the sex attractants of females ofOstrinia nubilalis andBombyx mori. The pheromone complex ofMamestra brassicae was reinvestigated and (Z)-9-hexadecenyl acetate and (Z)-11-hexadecenol were found in addition to already known pheromone components of this species. By using the solid-sample injection, the exact site of pheromone release could be determined inM. brassicae.Pheromones 52. Pheromones, 51: Bestmann, H.J., and Schmidt, M. 1985.Tetrahedron Lett 26:6171–6174.     

Sex pheromone components of female smaller tea tortrix moth,Adoxophyes sp. (Lepidoptera: Tortricidae) in Taiwan

(Z)-11-Teiradecenyl acetate (Z11-14: Ac) and (Z)-9-tetrade-cenyl acetate (Z9–14: Ac) were isolated as major sex pheromone components from the female tips of the smaller tea tortrix moth,Adoxophyes sp., in Taiwan. The average amount ofZ11- andZ9–14: Ac in each female gland was 24.9 and 14.1 ng, in a ratio of 6436, respectively. When compared to a closely related Japanese strain, which used theZ9-14: Ac,Z11-14 Ac,E11–14:Ac, 10-Me-12:Ac four-component system (in a ratio of 633142), the Taiwan formulation of two components caught significantly more Taiwan males than the Japanese formulation of four components.     

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.     

Sex pheromone ofStenoma cecropia Meyrick (Lepidoptera: Elachistidae)

(Z,E)-9,11-tetradecadienal (Z9,E11–14: Ald; 11%), (Z,E)-9,11,13-tetradecatrienal (Z9,E11, 13–14: Ald; 67%), (Z,E)-9,11-tetradecadienyl acetate (Z9,E11–14: Ac, 5.5%), and (Z,E)-9,11,13-tetradecatrienyl acetate (Z9,E11,13–14: Ac; 16.5%) were identified in the extracts of female pheromone glands ofStenoma cecropia (Lepidoptera: Elachistidae). From electroantennograms and single sensillum recordings, receptors toZ9,E11,13–14:Ald andZ9,E11–14: Ald were found on male antenna. Behavioral data were obtained from olfactometric tests in the laboratory and field trapping experiments in Colombia. It appeared that a blend ofZ9,E11,13–14:Ald (83%) andZ9,E11–14:Ald (17%) was attractive to males. These aldehydes are assumed to be components of the sex pheromone ofS. cecropia, whereas the acetates found in gland extracts might be precursors of the pheromone.     

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 an attractant for the caneborerSesamia grisescens walker (Lepidoptera: Noctuidae)

The composition of the sex pheromone ofSesamia grisescens was investigated using gas chromatography, electroantennograms, and field trapping. (Z)-11-Hexadecenyl acetate and (Z)-11-hexadecenol were identified in field tests as the major attractants. Trapping trials identified a 3:2 blend of these compounds as the most effective bait. Gas chromatography indicated the presence of hexadecyl acetate. (Z)-9-hexadecenyl acetate, (Z)-9-hexadecenol, and (E)-11-hexadecenyl acetate in the pheromone gland, but these compounds had no significant effect on trap catches when added to the major components. Traps baited with the major components in a 1:1 ratio caught more male moths than traps baited with virgin females.     

Female sex pheromone components ofHeliothis peltigera (Lepidoptera: Noctuidae)

Ten compounds were found in the sex pheromone glands ofHeliothis peltigera (Schiff) and identified as tetradecenal, (Z)-9-tetradecenal, (Z)-9-tetradecenol, (Z)-9-tetradecenyl acetate, hexadecanal, (Z)-7-hiexadecenal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, (Z)-11-hexadecenol, and (Z)-11-hexadecenyl acetate. Behavioral tests in a wind tunnel and subsequent trapping studies conducted in the field indicated that (Z)-11-hexadecenal and (Z)-9-tetradecenal are the main pheromone components ofH. peltigera. Addition of (Z)-11-hexadecenol to the binary blend did not enhance the capture of males ofH. peltigera, but it decreased the number of males of the sympatricH. armigera. Rubber septa impregnated with a mixture of 2 mg (Z)-11-hexadecenal + 1 mg (Z)-9-tetradecenal + 0.6 mg (Z)-11-hexadecenol are recommended for monitoringH. peltigera. Contribution from the Agricultural Research Organization (ARO), No. 2454-E, 1988 series.     

Spodoptera exigua: Capture of feral males in traps baited with blends of pheromone components

Field tests were conducted with various blends of acetates and alcohols previously identified as components of the sex pheromone for the beet armyworm (BAW),Spodoptera exigua (Hübner). The compounds were formulated on rubber septa and placed in sticky traps positioned in fields populated withAmaranthus sp., a favored host of this species. Moth captures were highest in traps baited with septa containing a blend of 0.1 mg (Z,E)-9,12-tetradecadien-1-ol acetate (Z9,E12–14∶Ac) and 0.01 mg(Z)-9-tetradecen-1-ol (Z9–14∶OH). Additionally, we confirmed that all combinations of acetates tested alone captured significantly fewer males than blends containing a 10∶1 ratio ofZ9,E12–14∶Ac andZ9–14∶OH. A 10∶1 formulation ofZ9,E12–14∶Ac andZ9–14∶OH in hollow fibers was also attractive to feral BAW males.     

Identification of a sex pheromone ofHeliothis subflexa (GN.) (Lepidoptera: Noctuidae) and field trapping studies using different blends of components

Eight compounds were isolated from the sex pheromone gland ofHeliothis subflexa (Gn.) and identified as hexadecanal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, (Z)-7-hexadecen-1-ol acetate, (Z)-9-hexadecen-1-ol acetate, (Z)-11-hexadecen-1-ol acetate, (Z)-9-hexadecen-1-ol, and (Z)-11-hexadecen-1-ol. Although the whole blend was found to be an effective male attractant, the deletion of alcohols from the blend increased trap captures considerably. Further, although the binary mixture of (Z)-9-hexadecenal and (Z)-11-hexadecenal caught some maleH. subflexa, significant increases in captures were noted when the three acetate components were included in the blend.Mention of a commercial or proprietary product in this paper does not constitute an endorsement of that product by the USDA or the State of Florida.     

Role of (Z)- and (E)-11-tetradecenyl acetate pheromone components in the sexual behavior of the (Z) strain of the european corn borer,Ostrinia nubilalis (Lepidoptera: Pyralidae)

A glass tube olfactometer bioassay was used to examine pheromone response of males of the (Z)-pheromone strain ofOstrinia nubilalis (Hubner). The presence of (E)-11-tetradecenyl acetate at the natural ratio to (Z)-11-tetradecenyl acetate (973; ZE) did not consistently elevate wing-fanning, upwind walking, or clasper extrusion over (Z)-11-tetradecenyl acetate alone. This bioassay did not reveal the behavioral role of (E)-11-tetradecenyl acetate.Published as Journal Article No. 10264 of the Michigan State University Agricultural Experiment Station.     

Sex pheromone components of the oblique-banded leafroller,Choristoneura rosaceana in the Okanagan Valley of British Columbia

(Z)-11-Tetradecen-1-yl acetate, (E)-11-tetradecen-1-yl acetate, and (Z)-11-tetradecen-1-ol were previously reported as the sex pheromone in New York strains of the oblique-banded leafroller,Choristoneura rosaceana (Harris), and (E)-11-tetradecen-1-ol was tentatively identified in female tip extracts. For Okanagan Valley strains ofC. rosaceana, an additional component, (Z)-11-tetradecenal, was identified from female tip extracts by split-less capillary gas-liquid chromatography and mass spectroscopy and was strongly stimulatory in electroantennogram studies. In field tests, 3 mg of 96.521.5 (Z)-11-tetradecen-1-yl acetate, (E)-11-tetradecen-1-yl acetate, and (Z)-11-tetradecen-1-ol (containing approx. 1%E isomer) was not as attractive as female-baited traps, and significant numbers of European leafrollerArchips rosanus L. were attracted. The above blend with 1% (Z)-11-tetradecenal added was significantly more attractive than traps baited with femaleC. rosaceana, butA. rosanus males were still attracted. Increased percentages of (Z)-11-tetradecenal up to 4% caused increased catches ofC. rosaceana and decreased catches ofA. rosanus. Low amounts of (E)-11-tetradecen-1-ol and (E)-11-tetradecenal male also contribute to increased specificity of the synthetic pheromone blend toC. rosaceana.Lepidoptera: Tortricidae.Contribution No. 638, Agriculture Canada, Research Station, Summerland, British Columbia, Canada.     

Isolation,identification, and biosynthesis of compounds produced by male hairpencil glands ofHeliothis virescens (F.) (Lepidoptera: Noctuidae)

Extracts of the intact hairpencil glands and hairs from the hairpencil glands of males ofHeliothis virescens (F.) were analyzed by capillary gas chromatography (GC) and by GC-mass spectroscopy. These analyses indicated that hexadecanyl acetate (212.4 ng/male), hexadecanol (22.3 ng/male), (Z)-11-hexadecenyl acetate (3.5 ng/male), octadecanyl acetate (14.2 ng/male) octadecanol (7.5 ng/male), tetradecanoic acid (2.7 ng/male), hexadecanoic acid (22.3 ng/male), and octadecanoic acid (6.5 ng/male) were present in the extracts. These compounds also were found in volatiles released from the hairpencil glands. In addition, GC analysis using both polar and apolar capillary columns indicated that extracts of the glands and extracts of the hairs from the hairpencil glands contained small amounts of tetradecanyl acetate, (Z)-9-tetradecenyl acetate, tetradecanol, (Z)-7-hexadecenyl acetate, (Z)-9-hexadecenyl acetate, and (Z)-11-hexadecenol. No (Z)-9-tetradecenal was present. Studies indicated that titers of the compounds increased rapidly during the 36 hr after adult eclosion and then leveled off, being maintained at high levels until released when the glandular hairs were exposed. During exposure of the hair pencils substantial amounts of the compounds were released. In vivo application of 500 ng of suspensions of (Z)-11-hexadecenyl acetate, (E)-11-hexadecenyl acetate, (Z)-11-tetradecenyl acetate, or (E)-11-tetradecenyl acetate in dimethyl sulfoxide to the surface of the denuded hairpencil gland showed that biosynthesis proceeds to the alcohol via the acetate.     

Role of sex pheromone components in behavioral reproductive isolation betweenAutographa gamma (L.) and eitherTrichoplusia ni (Hübner) ORChrysodeixis chalcites (Esp.) (Lepidoptera: Noctuidae: Plusiinae)

The composition of theAutographa gamma sex pheromone was reexamined and only (Z)-7-dodecenyl acetate and (Z)-7-dodecenol were identified by capillary GC, GC-MS, and dimethyl disulfide derivatization and subsequent GC-MS analysis. The fatty acid content of the pheromone glands was also studied, and a series of saturated and unsaturated acids was identified. However, most of the related pheromonal compounds were not detected. The male response to the pheromone components was studied in a flight tunnel and compared with the response to calling females. The best synthetic baits evoked a response similar to that observed to the virgin females, but males spent significantly more time at calling females than at the synthetic baits. The preferred synthetic baits consisted of (Z)-7-dodecenyl acetate alone or of a blend with 5% (Z)-7-dodecenol. Increasing the relative amount of the alcohol caused a gradual reduction in male response, particularly in the last steps of the courtship sequence. The addition of the minor sex pheromone components of the sympatric Plusiinae species,Trichoplusia ni andChrysodeixis chalcites, to theA. gamma pheromone was also investigated in the flight tunnel. Some of these components exhibited a significantly antagonistic effect on theA. gamma male courtship behavior. The most potent antagonists were (Z)-5-dodecenyl acetate and (Z)-9-tetradecenyl acetate. The response ofA. gamma andT. ni males to conspecific and heterospecific females was also compared in the flight tunnel. WhereasA. gamma males were attracted only to their conspecific females, a small percentage ofT. ni males were also attracted toA. gamma females and 11% performed the whole courtship sequence.Contribution from the Agricultural Research Organization (ARO), No. 3459-E, 1992 series.     

Female-produced sexual pheromone ofSceliodes cordalis (Lepidoptera: Pyralidae)

(E)-11-Hexadecen-1-yl acetate and (E)-11-hexadecen-1-ol were identified in extracts from the abdominal pheromone gland of femaleSceliodes cordalis and in a 1∶1 ratio acted as a potent field attractant for males. Sustained upwind flight by males to this mixture in a wind tunnel confirmed the identity of these compounds as major components of the natural sex pheromone of this species. The synthetic pheromone was used to define the annual limits of male flight activity. In the presence of 1–10 μg of pheromone per liter of air, the mating rate of laboratory populations was halved. TheZ isomers of both pheromone components decreased the numbers of males captured in traps baited with virgin females in the field and inhibited upwind flight in the wind tunnel. The attraction of males ofMnesictena flavidalis to virgin females ofS. cordalis and synthetic mixtures was demonstrated to be due to the acetate component alone. MaleEudonia sp. nrlinealis were captured by (Z)-11-hexadecen-1-yl acetate.