Laboratory and field tests with the synthetic sex pheromone of threeMatsucoccus 1 pine bast scales

Matsunone, (2E,4E)-4.6,10,12-tetramethyl-2,4-tridecadien-7-one, is the primary sex pheromone ofMatsucoccus resinosae, M. thunbergianae, andM. matsumurae. The synthetic compound was tested in the laboratory and in field tests with all three species, and significantly more males responded to synthetic matsuone than to controls. The attraction of synthetic matsuone to males in field tests was not significantly different from that of virgin females at the same matsuone release rate. An analog of matsuone previously shown to be biologically active was also tested in the laboratory withM. resinosae andM. thunbergianae, and field tested withM. resinosae. The active analog required a dose approximately 100 times greater than matsuone to yield maximum laboratory bioassay response, and in field tests, attraction was not significantly different from controls at doses at which matsuone was significantly attractive.Homoptera: Coccoidea: Margarodidae.Deceased.     

Response ofMatsucoccus thunbergianae males to synthetic sex pheromone and its utilization for monitoring the spread of infestation

Attraction of (2E,4E,6R,10R)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one [1; (6R,10R)-matsuone] and its antipode [2; (6S,10S)-matsuone] toMatsucoccus thunbergianae males was studied in the laboratory and in the field. They showed stronger response to1. In laboratory bioassays, the threshold concentrations for male attraction with1 and2 were 16 fg and 150 pg, respectively. In the field, during the first two days after traps were set, traps baited with 50 µg of1 on rubber septa or filter paper rolls caught more males than control traps. Between the sixth day and the tenth day after traps were set, in a daily trap catch experiment, the traps with 50 µg of1 on filter paper rolls caught more males than control traps on one day only, whereas those on rubber septa were always effective. The shape of the traps did not affect male catches. Males were caught on pheromone traps in locations where no scales were found by the customary detecting procedures.     

Outdoor attractancy of males ofMatsucoccus josephi (Homoptera: Matsucoccidae) andElatophilus hebraicus (Hemiptera: Anthocoridae) to synthetic female sex pheromone ofMatsucoccus josephi

The active component of the sex pheromone ofMatsucoccus josephi is (2E,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one; the chemical is also a powerful kairomone of adult males and females of the bugElatophilus hebraicus the principal predator ofM. josephi. The presence of theZ isomer (2E,6Z,8E)-5,7-dimethyl-2,6,8-decatrien-4-one does not interfere with the attractancy of the activeE component forM. josephi males or the bug. Our results show a clear dose-response between trap catch ofM. josephi males andE. hebraicus. Conversely, increasing amounts of theZ isomer in the mixture did not affect the attraction of the scale insect males or the bug. The catch ofM. josephi males did not differ significantly among traps of different color, and was significantly higher with traps attached to the tree trunk than those suspended between trees. Comparison of the catch ofM. josephi among the three forests and between pine species suggests that the level of infestation ofPinus halepepsis andPinus brutia ssp.brutia is similar, despite the fact that the latter pine is resistant to the scale insect. Both sexes ofE. hebraicus were trapped in much lower numbers at the more infested sites. This may be related to interference with the activity ofE. hebraicus due to deterioration and drying of parts of the tree crowns and heavy colonization by generalist predators in injured trees.     

Chirality of israeli pine bast scale,Matsucoccus josephi (homoptera: Matsucoccidae) sex pheromone

The absolute configuration of the sex pheromone of the Israeli pine bast scale,Matsucoccus josephi, was determined as (2E,5R,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one, designated here asR-E with 10% (2E,5S,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one, designated asS-E. The chirality of the quantitatively minorZ isomer was (2E,5R,6Z,8E)-5,7-dimethyl-2,6,8-decatrien-4-one (R-Z). Chiral assignments were made by comparative gas chromatographic (GC) analysis of naturalM. josephi pheromone with stereoselectively synthesized stereoisomers on a chiral Cyclodex-B column, which separated the enantiomers with baseline resolution. In gas chromatographic-electroantennographic detection (GC-EAD) analysis of the racemicZ andE isomers, the latter elicited the stronger antennal response by maleM. josephi. In GC-EAD of all four stereoisomers, employing the chiral column,R-E was the most active stereoisomer. In field testsR-E attracted 10 times more males ofM. josephi than didS-E. The racemicE/Z pheromone mixture, containing all four stereoisomers in approximately equal amounts, attracted as many maleM. josephi as did an equivalent amount ofR-E, indicating that the other stereoisomers are not inhibitory. The same keto-diene moiety with the same chiral center and configuration in all three known Matsucoccidae sex pheromones implies a common biosynthetic pathway and phylogenetic relationship.Contribution from the Agricultural Research Organization, the Volcani Center, No. 1496-E, 1994 series.Part of the work was performed during a sabbatical leave of E.D. at Simon Fraser University.     

Pheromones in red pine cone beetle,Conophthorus resinosae hopkins,and its synonym,C. banksianae McPherson (Coleoptera: Scolytidae)

Analyses of abdominal extracts and beetle-produced volatiles revealed that femaleConophthorus resinosae andC. banksianae produced optically pure (E)-(+)-pityol [(2R,5S)-(+)-2-(1-hydroxy-1-methylethyl)-5-methyltetrahydrofuran]. In field tests, traps baited with (E)-(±)- or (E)-(+)-pityol captured only males. Addition of host oils to traps baited with pityol did not significantly enhance the capture of males. Males of these former sibling species produced the spiroacetal (5S,7S)-(–)-7-methyl-1,6-dioxaspiro[4.5]decane with high optical purity (96%). Addition of the racemate or the optical isomers of the spiroacetal to traps baited with (E)-(±)-pityol almost completely inhibited the capture of males. It is hypothesized that to ensure their reproductive success, males produce the spiroacetal to repel rival males. Species specificity in pityol and the spiroacetal was not found betweenC. resinosae andC. banksianae, thus supporting their synonymy.     

Identification of Sex Pheromone Components of the Hessian Fly, <Emphasis Type="Italic">Mayetiola destructor</Emphasis>

Coupled gas chromatographic (GC)–electroantennographic detection (EAD) analyses of ovipositor extract of calling Hessian fly, Mayetiola destructor, females revealed that seven compounds elicited responses from male antennae. Four of the compounds—(2S)-tridec-2-yl acetate, (2S,10Z)-10-tridecen-2-yl acetate, (2S,10E)-10-tridecen-2-yl acetate, and (2S,10E)-10-tridecen-2-ol—were identified previously in female extracts. Two new EAD-active compounds, (2S,8Z,10E)-8,10-tridecadien-2-yl acetate and (2S,8E,10E)-8,10-tridecadien-2-yl acetate, were identified by GC–mass spectroscopy (MS) and the use of synthetic reference samples. In a Y-tube bioassay, a five-component blend (1 ng (2S)-tridec-2-yl acetate, 10 ng (2S,10E)-10-tridecen-2-yl acetate, 1 ng (2S,10E)-10-tridecen-2-ol, 1 ng (2S,8Z,10E)-8,10-tridecadien-2-yl acetate, and 1 ng (2S,8E,10E)-8,10-tridecadien-2-yl acetate) was as attractive to male Hessian flies as a similar amount of female extract (with respect to the main compound, (2S,10E)-10-tridecen-2-yl acetate). The five-component blend was more attractive to male flies than a three-component blend lacking the two dienes. Furthermore, the five-component blend was more attractive than a blend with the same compounds but that contained one tenth the concentration of (2S,8E,10E)-8,10-tridecadien-2-yl acetate (more accurately mimicking the ratios found in female extract). This suggests that the ratios emitted by females might deviate from those in gland extracts. In a field-trapping experiment, the five-component blend applied to polyethylene cap dispensers in a 100:10 μg ratio between the main component and each of the other blend components attracted a significant number of male Hessian flies. Also, a small-plot field test demonstrated the attractiveness of the five-component blend to male Hessian flies and suggests that this pheromone blend may be useful for monitoring and predicting Hessian fly outbreaks in agricultural systems.     

Specificity of Pheromonal and Kairomonal Response of the Israeli Pine Bast Scale Matsucoccus josephi and Its Predator Elatophilus hebraicus

It has been demonstrated previously that the sex pheromone of the Israeli pine bast scale, Matsucoccus josephi, (2E,5R,6E,8E)-5,7-dimethyl2,6,8-decatrien-4-one (1) is also a potent kairomone of the scale insect's predator Elatophilus hebraicus. Surprisingly, the sex pheromones of M. feytaudi (2) and M. matsumurae (3) also attract E. hebraicus. These results have prompted us to prepare a series of analogs of 1 with variations in the two moieties attached to the C=O group (4–9) in order to probe the structure–activity relationship of the pheromonal/kairomonal response of M. josephi and E. hebraicus. The most selective and active pheromone analog is 8, attracting only M. josephi males and the most selective and active kairomone analog is the M. feytaudi pheromone 2, attracting only adults of E. hebraicus. A dose–response field test of these analogs and the chiral and racemic M. josephi pheromone 1 indicates that the specificity is maintained at a broad range between 25 and 400 g corresponding to 1. Analog 5, which is neither a parapheromone nor a kairomone, and analog 8, which is only a parapheromone, are not inhibitory to M. josephi or to E. hebraicus. Our study indicates that alterations in the diene side chain of 1, common to all three Matsucoccus pheromones, strongly reduce the kairomonal activity while structural changes in the second side chain significantly reduce the pheromonal activity. The discovery of selective analogs of 1 has practical implications and enables specific monitoring of M. josephi or E. hebraicus. Particularly important is the possibility to mass-trap males of M. josephi without reducing the population of E. hebraicus.     

(Z,Z)-4,7-tridecadien-(S)-2-yl acetate: sex pheromone of Douglas-fir cone gall midge,Contarinia oregonensis

Our objectives were to identify and field test the sex pheromone of female Douglas-fir cone gall midge, Contarinia oregonensis (Diptera: Cecidomyiidae). Coupled gas chromatographic–electroantennographic detection (GC-EAD) analyses of pheromone extract revealed a single compound (A) that elicited responses from male antennae. Hydrogenation of pheromone extract, followed by renewed GC-EAD analysis, revealed a new EAD-active compound with chromatographic characteristics identical to those of tridecan-2-yl acetate on five fused silica columns (DB-5, DB-210, DB-23, SP-1000, and Cyclodex-B). Syntheses, chromatography, and retention index calculations of all possible tridecen-2-yl acetates suggested that the candidate pheromone A was a tridecadien-2-yl acetate with nonconjugated double bonds. Synthetic candidate pheromone component (Z,Z)-4,7-tridecadien-2-yl acetate (Z4Z7) cochromatographed with A on all analytical columns and elicited comparable antennal activity. In GC-EAD analyses that separated the enantiomers (Z,Z)-4,7-tridecadien-(S)-2-yl acetate (2S-Z4Z7) and (Z,Z)-4,7-tridecadien-(R)-2-yl acetate (2R-Z4Z7) with baseline resolution, only 2S-Z4Z7 as a component in a racemic standard or in pheromone extract elicited antennal responses. In Douglas-fir seed orchards, sticky traps baited with 2S-Z4Z7 captured male C. oregonensis, whereas 2R-Z4Z7 was behaviorally benign. Comparable catches of males in traps baited with racemic Z4Z7 (50 g) or virgin female C. oregonensis suggested that synthetic pheromone baits could be developed for monitoring C. oregonensis populations in commercial Douglas-fir seed orchards.     

(Z,Z)-6,9-heneicosadien-11-one,labile sex pheromone of the whitemarked tussock moth,Orgyia leucostigma

The whitemarked tussock moth (WMTM), Orgyia leucostigma (J. E. Smith), is a major pest of coniferous and deciduous trees in eastern Canada. Chemical identification of its sex pheromone depended primarily on GC-EAD and HPLC analysis, with confirmation of behavioral activity by wind tunnel and field tests. We identified (Z,Z)-6,9-heneicosadien-11-one (Z,Z-6,9-ket) at 4–5 ng/female as the only essential sex pheromone component. Also detected in female extracts were (Z)-6-heneicosen-11-one (Z6-ket) at 2.5 ng/female, (Z,E)-6,8-heneicosadien-11-one (Z,E-6,8-ket) at about 0.5 ng/female, and a trace amount of (Z,E)-6,9-heneicosadien-11-one. Traps containing as little as 1 g of Z,Z-6,9-ket attracted males at low population levels, indicating it is a potent sex attractant. Traps baited with Z6-ket attracted few males, and in wind-tunnel bioassays it was at least 100-fold less attractive to males than Z,Z-6,9-ket. No improvement in trap catch occurred with the addition of Z6-ket in various binary mixtures with Z,Z-6,9-ket, including the female ratio, and a ternary mixture of Z,Z-6,9-ket, Z6-ket, and Z,E-6,8-ket in the 9:5:1 ratio detected in females was no better than Z,Z-6,9-ket alone. We attribute the presence of Z,E-6,8-ket and Z,E-6,9-ket in female extracts to the spontaneous and rapid stereospecific isomerization of Z,Z-6,9-ket at room temperature. Male flight began at sunset but peaked during the second half of the night.     

Identification Of Sex Pheromone Components Of The Painted Apple Moth: A Tussock Moth With A Thermally Labile Pheromone Component

The sex pheromone of the painted apple moth, Teia anartoides (Lymantriidae) was investigated using GC-EAD and GC-MS analysis, derivatization, TLC analysis, and field cage and field trapping bioassays. The major sex pheromone components were identified as (6Z,9Z)-henicosa-6,9-dien-11-one and (6Z,9Z)-henicosa-6,9-diene. Other minor components of pheromone gland extracts included (6Z)-9R,10S-epoxyeicos-6-ene, (6Z)-9R,10S-epoxyhenicos-6-ene, (6Z,9Z)-henicosa-6,9-dien-11-ol, (6Z)-henicos-6-en-11-one, and (6Z, 8E)-henicosa-6,8-dien-11-one, but the roles of these minor components remain equivocal. In field cage and field experiments, a blend of all seven identified components [(6Z,9Z)-henicosa-6,9-dien-11-one (relative amount 100), (6Z,9Z)-henicosa-6,9-diene (100), (6Z)-9R,10S-epoxyeicos-6-ene (5), (6Z)-9R,10S-epoxyhenicos-6-ene (10), (6Z,9Z)-henicosa-6,9-dien-11-ol (5), (6Z)-henicos-6-en-11-one (1), and (6Z,8E)-henicosa-6,8-dien-11-one (25)] was as attractive to males as calling females, but tests with blends of the major component(s) with subsets of the minor components did not produce consistent results that unequivocally showed the various minor components to be critical components of the active blend. (6Z,9Z)-henicosa-6,9-dien-11-one is thermally labile and rearranges to (6Z,8E)-henicosa-6,8-dien-11-one and other products at ambient temperature, rendering the synthetic pheromone lure inactive after two days of field exposure.     

New Pheromone Components of the Grapevine Moth <Emphasis Type="Italic">Lobesia botrana</Emphasis>

Analysis of extracts of sex pheromone glands of grapevine moth females Lobesia botrana showed three previously unidentified compounds, (E)-7-dodecenyl acetate and the (E,E)- and (Z,E)-isomers of 7,9,11-dodecatrienyl acetate. This is the first account of a triply unsaturated pheromone component in a tortricid moth. The monoenic acetate (E)-7-dodecenyl acetate and the trienic acetate (7Z,9E,11)-dodecatrienyl acetate significantly enhanced responses of males to the main pheromone compound, (7E,9Z)-7,9-dodecadienyl acetate, in the wind tunnel. The identification of sex pheromone synergists in L. botrana may be of practical importance for the development of integrated pest management systems. Electronic supplementary material Supplementary material to this paper is available in electronic form at and accessible for authorised users.     

(Z)-10-Heptadecen-2-one and other 2-ketones in the aggregation pheromone blend ofDrosophila martensis,D. buzzatii,andD. serido

(Z)-10-Heptadecen-2-one was identified as the major aggregation pheromone component inDrosophila martensis, D. buzzatii, andD. serido. Aliphatic 2-ketones were not detected in newly eclosed males or in virgin females of any age. The amount of (Z)-10-heptadecen-2-one in the ejaculatory bulb and on the cuticle of males increased with age. Only trace quantities of (Z)-10-heptadecen-2-one were transferred to the female during mating. 2-Tridecanone was found in the ejaculatory bulb and on the cuticle of maleD. martensis andD. buzzatii, but notD. serido. The amount of 2-tridecanone increased with age. Unexpectedly,2-tridecanone inhibited the aggregation activity of (Z)-10-heptadecen-2-one inD. buzzatii. InD. martensis, 2-tridecanone was significantly less attractive than controls but did not decrease the attractiveness of one fly equivalent of (Z)-10-heptadecen-2-one.D. serido males did not have any 2-tridecanone and the activity of (Z)-10-heptadecen-2-one was not diminished inD. serido by the presence of 2-tridecanone.     

Behavior of processionary males (Thaumetopoea pityocampa) induced by sex pheromone and analogs in a wind tunnel

The behavioral response of processionary males (Thaumetopoea pityocampa) to the natural pheromone (Z)-13-hexadecen-11-ynyl acetate (1) and structurally related analogs in a wind tunnel is presented. Stereomerically pureZ-1 and a mixture with theE isomer in 80:20 ratio elicited similar attraction responses at 1 µg and higher. The activity was dose-dependent, being optimum at 1 µg with 90% and 80% of males contacting with the source in the presence of theZ-1 andZ/E-1, respectively. 11-Hexadecynyl acetate (2) functioned as a pheromone mimic, being able to induce the complete mate-finding behavioral sequence, although its activity was much lower than that of the pheromone. (Z)-13-Hexadecen-11-ynyl alcohol (3) and, particularly, (Z)-13-hexadecen-11-ynal (4) were potent inhibitors of the upwind flight response in mixtures withZ-1 in 99:1, 95:5, and 91:9 ratios. (Z)-1,1,1-Trifluoro-16-nonadecen-14-yn-2-one (5) also inhibited the response of males to pheromone, particularly in the source contact behavior. Comparison with activity displayed by analogs in field tests is also reported.     

Sex Attractant Pheromone from the Neotropical Red-Shouldered Stink Bug, <Emphasis Type="Italic">Thyanta perditor</Emphasis> (F.)

Olfactometer bioassays showed that odors from mature Thyanta perditor males attracted females but not males. Furthermore, odors from females did not attract either sex, indicating that like other phytophagous pentatomid bugs, the males produce a sex pheromone. Attraction appeared to peak in late afternoon to evening. The headspace volatiles collected from male and female T. perditor were analyzed by GC-MS and HPLC. A male-specific compound, methyl (2E,4Z,6Z)-decatrienoate (2E,4Z,6Z-10:COOMe), was identified along with a number of other compounds found in extracts from both sexes. Bioassays carried out with 2E,4Z,6Z-10:COOMe showed it was as attractive to females as the crude extract of male volatiles, suggesting that the male-produced sex pheromone consists of 2E,4Z,6Z-10:COOMe as a single component. Consecutive volatiles collections from males showed that 2E,4Z,6Z-10:COOMe began appearing in extracts from males about 9 d after the final molt, as the males became sexually mature.     

Female sex pheromone of the Yunnan pine caterpillar moth Dendrolimus houi: first (E,Z)-isomers in pheromone components of Dendrolimus spp

The Yunnan pine caterpillar Dendrolimus houi Lajonquière is a serious defoliator of coniferous forests in southwestern China. Gas chromatography–electroantennography (GC–EAG) analyses of extracts of female sex pheromone glands of D. houi moths revealed the presence of three compounds eliciting antennal responses. These were identified as (5E,7Z)-5,7-dodecadien-1-ol (E5,Z7-12:OH), (5E,7Z)-5,7-dodecadien-1-yl acetate (E5,Z7-12:OAc), and (5E,7Z)-5,7-dodecadienal (E5,Z7-12:Ald) by comparison of their GC retention indices, mass spectra, and EAG activities with those of synthetic standards. Average amounts of E5,Z7-12:OH, E5,Z7-12:OAc, and E5,Z7-12:Ald per calling virgin D. houi female were 14.7 ± 12.9 ng (± SD), 5.8 ± 5.4 ng, and 0.8 ± 1.4 ng, respectively, in a ratio of 100:39.7:5.6. These three components were also collected from the headspace of calling virgin female moths by solid-phase microextraction (SPME). In addition, trace quantities of (Z)-5-dodecen-1-ol (Z5-12:OH), (5Z,7E)-5,7-dodecadien-1-ol (Z5,E7-12:OH), (5E,7E)-5,7-dodecadien-1-ol (E5,E7-12:OH), (5Z,7E)-5,7-dodecadien-1-yl acetate (Z5,E7-12:OAc), (5Z,7Z)-5,7-dodecadien-1-yl acetate (Z5,Z7-12:OAc), and (5E,7E)-5,7-dodecadien-1-yl acetate (E5,E7-12:OAc) were tentatively identified in female pheromone gland extracts by selected ion monitoring GC-MS. Field trapping experiments showed that E5,Z7-12:OH, E5,Z7-12:OAc, and E5,Z7-12:Ald were essential for attraction of male D. houi moths. Traps baited with a 20:1:1 blend (alcohol/acetate/aldehyde) loaded on gray rubber septa were as effective as traps baited with virgin female moths. The optimum ratio of acetate to aldehyde was 1:1, and this ratio was more critical than the ratio of either compound to the alcohol. This represents the first example of (E,Z)-isomers in pheromone blends of Dendrolimus species.     

(E)- and (Z)-6-nonen-2-one: Biosynthetic precursors ofEndo- andexo-brevicomin in two bark beetles (Coleoptera: Scolytidae)

The ability of (E)- and (Z)-6-nonen-2-one to serve as precursors of the common scolytid pheromonesEndo- andexo-brevicomin was examined in vivo. When mountain pine beetles (MPB),Dendroctonus ponderosae Hopkins, or western balsam bark beetles (WBBB),Dryocoetes confusus Swaine, were exposed to [6,7-D₂](E)-6-nonen-2-one, theEndo-brevicomin produced was enriched with two deuterium atoms per molecule (as determined by GC-MS), indicating that (E)-6-nonen-2-one served as a precursor of this pheromone. Similarly, when the beetles were exposed to [4,4-D₂](Z)-6-nonen-2-one, theexo-brevicomin produced was enriched with two deuterium atoms per molecule. Evidence in support of biological relevance of the latter observation include: (1) (Z)-6-nonen-2-one was found in the volatiles of male MPBs and WBBBs, indicating that this is a natural metabolite; (2) theexo-brevicomin produced by MPB was shown to be of natural (+) chirality by complexation chromatography; and (3) female WBBBs and MPBs (which are not known to produceexo-brevicomin) produced significantly lessexo-brevicomin when exposed to the precursor than did the males.     

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.     

Cross-attraction between two species ofMatsucoccus

In laboratory bioassays, males ofMatsucoccus resinosae fromPinus resinosa in New York andMatsucoccus n. sp. fromPinus thunbergiana in Korea were strongly attracted to crude hexane extracts ofM. resinosae females, andM. resinosae males responded strongly to extracts ofMatsucoccus n. sp. females. Males of the two species responded similarly to gas chromatographic fractions and subfractions of a pentane extract ofM. resinosae females. Sex pheromones of these two species appear to be the same or very similar.Homoptera: Coccoidea: Margarodidae.     

Field response of maritime pine scale,Matsucoccus feytaudi duc. (Homoptera: Margarodidae), to synthetic sex pheromone stereoisomers

The absolute configuration of the primary component of the maritime pine scale (Matsucoccus feytaudi) pheromone (i.e., (8E, 10E)-3,7,9-trimethyl-8,10-dodecadien-6-one) was determined as 3S,7R by field-trapping experiments using synthetic stereoisomers and according to previous NMR considerations. The 3R,7R isomer showed similar activity to 3S,7R, whereasM. feytaudi males responded very weakly to the two other candidates (3R,7S and 3S,7S). Further studies were conducted to optimize scale trapping for monitoring scale populations. Results of these studies showed that the trapping efficiency was related to pheromone dose, trap area, and wind speed but not to trap height.     

Sex Attractant Pheromone of Saturniid Moth Coloradia velda

The female-produced sex attractant pheromone of Coloradia velda has been identified by a combination of analytical methods and field tests as a blend of (10E,12Z)-hexadecadien-1-yl acetate (10E,12Z–16:Ac), (10E,12E)-hexadecadien-1-yl acetate (10E,12E–16:Ac), and (10E,12Z)-hexadecadien-1-ol (10E,12Z–16:OH) in a 10:1:0.33 ratio, respectively. The corresponding aldehyde (10E,12Z–16:Ald) was also found in extracts of female pheromone glands, but in blends with 10E,12Z–16:Ac and 10E,12E–16:Ac at low doses did not significantly increase the attractiveness of baits to male moths.