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Adult male and female rustic borers, Xylotrechus colonus F. (Coleoptera: Cerambycidae), aggregate on cut logs and fallen trees that are the hosts of their larvae. Our studies show that male X. colonus actively search for females, and only respond to them after contacting them with their antennae. Stripping cuticular hydrocarbons from females with solvent rendered them unattractive to males, suggesting that males did not recognize females by mechanoreception alone. Reapplying solvent extract to washed females restored their attractiveness to males, confirming the role of cuticular hydrocarbons in mate recognition. Female cuticular hydrocarbon extracts contain n-pentacosane, 9-methylpentacosane, and 3-methylpentacosane, components that were either absent or present in very small amounts on males. We demonstrate that the contact pheromone is a blend of these three cuticular hydrocarbons.

The sex pheromone of the vine mealybug Planococcus ficus Signoret has been identified as a single component, lavandulyl senecioate. Racemic lavandulyl senecioate was as attractive to male mealybugs as the insect-produced (S)-enantiomer, indicating that the unnatural enantiomer is not inhibitory. Lavandulol, which also was found in extracts from virgin females, antagonized attraction of males at higher doses. Rubber septum lures loaded with 10- to 1,000-microg doses of the pheromone were equally attractive, and lures loaded with 100 microg of racemic pheromone remained attractive for at least 12 wk under field conditions. Delta traps were more effective than double-sided sticky cards and minimized captures of nontarget insects. Pheromone-baited traps had an effective range of at least 50 m. Comparison of visual sampling methods and sampling of males with pheromone-baited traps revealed that trap catches were significantly correlated with the results from visual sampling methods, and with economic damage.

Publisher Summary This chapter reviews the methods that have been developed for the collection and isolation of insect pheromones and related compounds. The chapter provides examples from other taxa. The apparatus and techniques for collection of trace quantities of pheromones, with adjustments for scale, are dictated more by the chemical and physical properties of the pheromones, and the physical circumstances required for their production or extraction, than by the particular organism. For example, the same general sampling techniques have been used to sample pheromones from organisms as small as single-celled gametes to as large as Asian elephants. With the identification of the first insect pheromone several decades ago, a series of specialized techniques have been developed to streamline the identification process. Such dynamic collection methods provide a more accurate representation of the pheromone blends produced by organisms than tissue extractions and allow repeated sampling from the same individuals. For small-scale collections, analytes may be trapped on short beds of Porapak Q, Tenax, or activated charcoal. For large-scale collection of analytes for bioassay or for spectroscopic analysis, large numbers of organisms can be placed in appropriate sized aeration chambers supplied with food and water, with collections continued indefinitely, changing the collectors periodically.

In North America, cerambycid beetles can have significant ecological and economic effects on forest ecosystems, and the rate of introduction and/or detection of exotic species is increasing. Detection and survey programs rely on semiochemical-baited intercept traps which are often ineffective for large woodborers like cerambycid beetles. This study examined the effects of flight intercept trap design on the capture of cerambycid beetles in the subfamilies Lamiinae and Cerambycinae. These subfamilies are the two largest in the Cerambycidae and they include many of the most damaging cerambycid pests and species on regulatory watch lists in North America. This study demonstrates that intercept trap design, treatment of trap surfaces with a lubricant, and the type of collection cup all influence the capture of beetles from the subfamilies Lamiinae and Cerambycinae. It also demonstrates that the addition of a large lubricant-treated collar to the bottom funnel of a multiple-funnel trap significantly increases the capture of some Lamiinae. The best trap design for both subfamilies was a lubricant treated multiple-funnel [MF] trap equipped with a wet cup and lubricant treated large collar on the bottom funnel. This design captured between 4 and 14 times more Lamiinae and Cerambycinae than commercially-available MF and panel traps.

The terminal dienyne of (9 Z )-9,13-tetradecadien-11-ynal, the sex pheromone of the avocado seed moth, Stenoma catenifer , was constructed by coupling a vinyl iodide precursor with commercially available 1-buten-3-yne with Pd catalysis, resulting in a short and efficient synthesis of the pheromone.

A female-produced sex pheromone for the pecan nut casebearer, Acrobasis nuxvorella Neunzig, has been identified from pheromone gland extracts of calling female moths. The compound (9E,11Z)-hexadecadienal [(9E,11Z)-16:Ald] was identified by coupled GC-EAD and retention time matches with a synthetic standard on four capillary GC columns of different polarities. Corroboration of the identification of (9E,11Z)-16:Ald by other analytical chemistry methods was not possible due to the minute quantities of pheromone extracted (1 picogram/female). In field studies, gray rubber septa impregnated with 100 micrograms of synthetic (9E,11Z)-16:Ald were attractive to male moths, whereas higher and lower doses were less attractive. The homologous (9E,11Z)-15:Ald was also slightly attractive while the more highly conjugated analogues, (9E,11Z,13Z)- and (9E,11Z,13E)-16:Ald, were not.

Unmated female or male cabbage looper moths,Trichoplusia ni (Hubner), were attracted more often in a flight tunnel to a cage with moths of the opposite sex and a bouquet of cotton foliage. Increased sexual attractiveness of females with plants may be a result of stimulation of pheromone release in response to plant odor, since more males were attracted when odor of cotton foliage was passed over females than when odor of females was passed over cotton foliage before venting into the flight tunnel. Increased sexual attractiveness of males with plants is due in part to host odor enhancement of female attraction to male pheromone, since more females were attracted to synthetic male pheromone (a blend of enantiomers of linalool and isomers of cresol) and a cotton leaf extract than were attracted to male pheromone alone. A short synthesis procedure was developed for (S)-(+)-linalool, the major component of the male sex pheromone, isolated from hair pencils, used in these tests.

Adults of the wood-boring beetlePhoracantha semipunctata F. showed variability in their attractiveness to five varieties ofEucalyptus when presented with an array of logs in a natural setting. Logs of two host varieties (E. camaldulensis Dehnhardt and the hybridE. trabutii) attracted two to three times more adult beetles than did logs of other host species (E. cladocalyx F.,E. grandis Hill ex Maiden andE. tereticornis Small). In the field, high oviposition rates byP. semipunctata adults resulted in severe competition among larvae. Larval survivorship was low in field logs ofE. trabutii and high inE. cladocalyx logs, although these hosts were the most and least attractive to the adult beetles, respectively. However, when logs were hand infested at low larval densities, survivorship ofP. semipunctata larvae was highest in logs of bothE. camaldulensis andE. trabutii. These findings suggest that adult beetles in the field were most attracted to those logs ofEucalyptus species that represented the highest quality hosts for their progeny under conditions of reduced larval competition.

Physical factors, such as the color of the oviposition substrate, have seldom been compared with chemical cues in their ability to elicit oviposition behavior in mosquitoes. The role of dyed oviposition waters in attracting ovipositingCulex quinquefasciatus was examined in laboratory experiments. Oviposition waters dyed with ink were found to be significantly attractive to ovipositingCx. quinquefasciatus when compared to distilled water controls. Experiments demonstrated that the mosquitoes were responding to the increased optical density of the dyed oviposition water rather than volatile components of the dye. Ink was also considered in combination with chemical oviposition cues. No comparative data exist on the effect of physical and chemical factors presented together on the oviposition behavior ofCx. quinquefasciatus. Waters dyed with ink acted synergistically with a five-component chemical attractant mixture (3-methylindole, indole, 4-methylphenol, 4-ethylphenol, and phenol) in inducing oviposition in a 2×2 factorial experiment.

The behavioral and electrophysiological activity of a mimic [(Z,E)7,9,11-dodecatrienyl formate] of the major sex pheromone component [(Z,E) 9,11,13-tetradecatrienal] of carob moth was assessed. Wind-tunnel bioassays demonstrated that the formate was as effective as natural gland extracts, and significantly more effective than the trienal alone or than the trienal blended with two minor pheromone components, in evoking source contact. Dispensers containing the formate were as effective as trienal-containing blend lures in attracting males when placed at the same dosage in traps in date gardens. Single-cell recordings showed that at least two olfactory neurons, differentiated by spike amplitude, are located in the long trichoid hairs on male carob moth antennae. Dose-response relationships indicated that puffs from cartridges loaded with at least 0.1 μg of the formate or of the trienal were necessary to elicit spiking by either the small or the large-spiking cell within a sensillum. Cross-adaptation studies demonstrated that both compounds stimulated the same large-spiking cell. The frequencies of spikes evoked from the large cell when stimulated by emissions from 0.1-μg, 1-μg, or 10-μg cartridges of either the formate or the trienal were not significantly different, suggesting that the formate is an effective mimic of the trienal at the antennal receptor cell level.

Several properties of the compound 3,4-dihydro-2H-pyrrole(A1-pyrroline), which has been reported as a component of the male-produced Mediterranean fruit fly pheromone, have been determined by [(1)H]- and [(13)C]nuclear magnetic resonance spectroscopy. The stability of Δ(1)-pyrroline in several solvents and at moderately elevated temperatures has been investigated, and it has been established that it exists as both a monomer and trimer in solution. Although equilibrium studies indicate that the trimer is thermodynamically more stable than the monomer in solution, only the monomer was found in the vapor phase based on infrared analysis.

Comparison of theoretical and experimental vibrational circular dichroism (VCD) spectra of an enantiopure synthetic sample of the obscure mealybug sex pheromone allowed the determination of the absolute configuration of the insect's pheromone.

The major components of the sex pheromone of Dioryctria abietivorella (Grote) (Lepidoptera: Pyralidae) were recently identified as (9Z,11E)-tetradecadien-1-yl acetate (9Z,11E-14:Ac) and a polyunsaturated, long-chain hydrocarbon (3Z,6Z,9Z,12Z,15Z)-pentacosapentaene (C25 pentaene). The optimal ratio of these components and the role of potential minor components were not fully determined in the initial short report on the pheromone's identification. We tested different ratios of the two major components loaded into grey halobutyl rubber septum dispensers, placed in sticky traps deployed in conifer breeding arboreta. The optimal ratio of the two components was 200 μg 9Z,11E-14:Ac to 2000 μg C25 pentaene. (Z)-9-Tetradecen-1-yl acetate, which had been identified previously in female pheromone gland extracts, and five other potential minor pheromone components, were tested individually as additions to the optimized two-component lure blend. None of the ternary blends were more attractive than the optimized two-component blend, at the ratios tested. Two lure adjuvants, a UV stabilizer (Sumisorb 300) and the antioxidant butylated hydroxytoluene, added individually or together, did not affect the attractiveness of the optimized lure blend. The Pherotech diamond sticky trap baited with the optimized lure blend was the most effective trap design among eight types of sticky trap and a bucket style trap that were tested. Traps baited with synthetic lures were as attractive as traps baited with virgin female moths. The optimized two-component lure blend in the Pherotech diamond trap is recommended for monitoring fir coneworm infestations. The availability of an effective synthetic pheromone opens the possibility for control tactics using mating disruption or attract-and-kill techniques.

A sesquiterpene-enriched fraction of ginger oil was treated with the dienophile 4-phenyl-1,2,4-triazoline-3,5-dione (2), which selectively formed a Diels−Alder adduct with the sesquiterpene hydrocarbon zingiberene (1). The adduct was purified by flash chromatography, then hydrolyzed to return zingiberene in good yield and >99% purity.

Sexually mature male stink bugs, Thyanta pallidovirens , release a male-specific blend of volatiles, including several sesquiterpene hydrocarbons, and the highly conjugated ester methyl (2 E ,4 Z ,6 Z )-deca-2,4,6-trienoate 1 . The latter compound was synthesized, and found to rearrange under GC conditions via a 1,7 sigmatropic rearrangement. © 1997 Elsevier Science Ltd.

Wheat is the most widely cultivated plant in the world, providing more than 20 % of the food calories consumed [1]. The Hessian fly, Mayetiola destructor (Say), (Diptera: Cecidomyiidae), is one of the most destructive pests of wheat and is found in most of the major wheat-growing areas of the world [2]. Due to the feeding habit of the larva and the type of damage it produces, early infestations by Hessian fly are extremely difficult to detect or predict. Female Hessian flies are known to produce a sex pheromone that elicits upwind flight by males [3] and, given the widespread use of synthetic sex pheromones in pest management programs [4], it is very likely that this sex pheromone could find great utility in controlling this pest. As well as containing a large number of pest species, the family Cecidomyiidae is of evolutionary interest because of its rapid rate of species formation relative to a lesser rate of speciation in related families of Diptera [5]. We report here the first identification of a cecidomyiid sex pheromone, that of the Hessian fly, as (2S)(E)-10-tridecen-2-yl acetate (Fig. 1). The crude sex pheromone was obtained by dissecting the terminal segments of the ovipositors of female Hessian flies, and extracting them in pentane. The activity of extracts, fractions of extracts, and synthetic chemicals was determined

A short, convergent synthesis of 1,3Z,6Z,9Z-tetraene hydrocarbons was developed. A key step was the regioselective alkylation of 1,5-dibromo-2-pentyne. The method was used to synthesize tetraenes of chain lengths C18–C20, to be used in field trials as sex attractants and (or) inhibitors of the winter moth, Operophterabrumata L., and the Bruce span worm O. bruceata H. (Lepidoptera: Geometridae).

(Z,Z,Z)-1,3,6,9-Nonadecatetraene is a sex pheromone that attracts males of both the winter moth Operophtera brumata (L.) and the Bruce spanworm O. bruceata (Hulst). Tests were run to maximize the specificity of a pheromone trap for the winter moth by the addition of a previously discovered Bruce spanworm male inhibitor (BSMI), (E,Z,Z)-1,3,6,9-nonadecatetraene. Trap capture inhibition of O. bruceata would facilitate monitoring of winter moth as males of the two species are difficult to distinguish without dissection. Wind tunnel tests with O. bruceata males responding to the pheromone indicated that BSMI has a more potent inhibitory effect if males physically contact the compound. Field tests in an area where only O. bruceata was found demonstrated that pheromone-baited traps caught fewer O. bruceata with BSMI placed on the outside of the entrance holes than when it was placed on the inside of the trap, catching respectively 97 and 82% fewer males than traps baited with the pheromone alone. In an area where O. brumata predominated, BSMI, whether inside or outside the trap, did not affect O. brumata captures. However, O. brumata trap captures were reduced when BSMI was placed on rubber rings glued to the outside of the entrance holes to the traps even though control rings did not affect O. brumata captures. Evidence is presented indicating that hybridization is taking place between these two species where O. brumata has recently been introduced and that the response of the hybrids to the BSMI is intermediate between the two species.

α-Methylbenzylamides, useful intermediates in the resolution of carboxylic acids, are cleaved with a two step procedure; enolizable amides are not racemized.

Gas chroinatography of hexane extracts of 3-day-old virgin A.frontella adults revealed a branched saturated hydrocarbon present only in females. This compound was isolated by argentation chromotography and preparative GC, identified by GC and GC-MS as 3,7-dimethylnonadecane, and subsequently synthesized. Three-day-old virgin females contained 54.1 ± 3.5 ng (± SEM;N = 48) of 3,7-dimethylnonadecane. Male cadavers do not elicit male courtship behavior, but when treated with ∼ 18 ng of 3,7-dimethylnonadecane they were as attractive as cadavers of 3-day-old virgin females. Black cotton knots were less attractive than male cadavers when treated with 3,7-dimethylnonadecane, but all bioassays indicated that this compound is an important semiochemical modulating male mating behavior.

A single sex pherormone component was isolated from abdominal tip extracts of female Bruce spanworm.Operophtera bruceata (Hulst). This was identified as (Z,Z,Z)-1,3,6,9-nonadecatetraene by capillary gas chromatography (GC), electroantennography, and mass spectrometry. In addition, hexane extracts of female abdominal tips from Bruce spanworm and the winter moth.O. brumata L., were analyzed by GC coupled to an electroantennographic detector (GC-EAD). The extracts ofO. bruceata andO. brumata females elicited only a single response, at the same retention time, from antennae of their conspecific and reciprocal males. In field tests conducted in Saskatchewan, traps baited with the synthetic tetraene captured Bruce spanworm males. In tests carried out on Vancouver Island, British Columbia, where the two species coexist, both Bruce spanworm and winter moth males were captured. The attractancy of lures containing the synthetic pheromone alone and in combination with several structurally related analogs was field tested at both locations. One of these, an isomer of the natural pheromone, (E,Z,Z)-1,3,6,9-nonadecatetraene, inhibited the capture of Bruce spanworm males but had no effect upon the number of winter moth males which were taken. Thus, populations of these two very similar species can be distinguished by employing traps baited with pheromone ± the inhibitor. Coneorifice Hara traps were found useful for field trapping males of both species.

Two biologically active macrolides were isolated from Porapak Q-captured beetle and frass volatiles ofCryptolestes turcicus (Grouvelle) and identified spectroscopically as (Z,Z)-5,8-tetradecadien-13-olide (I) and (Z)-5-tetradecen-13-olide (II). Natural I was active alone and was synergized by inactive II. The pheromones were male-produced but attractive to both sexes. Pheromone production increased dramatically when insects were aerated on a food source. Pure (R)- and (S)-I were inactive, but mixtures of (R)- and (S)-I were active, the first reported instance of enantiomeric synergism in the Cucujidae.

Synthese de cis-epoxy-6,7 alcadienes-3,9 (chaines C18 a C22 a partir d'octadiene-2,5ol-1 et d'alcynes-1 (C10 a C14) via la reacion d'iodomethyl-2 pentene-2yl-3 oxiranne et des bromures d'alcene-1yl magnesiums (C10 a C14)