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ABSTRACT: We report identification and field testing of 2-(undecyloxy)-ethanol (monochamol) as a sex-specific, aggregation pheromone component produced by males of Monochamus scutellatus scutellatus (Say) (Coleoptera: Cerambycidae), a longhorned beetle native to North America. A congener, Monochamus notatus (Drury), which uses the same hosts as M. s. scutellatus, also was attracted to this compound in field trials, suggesting it may be a pheromone component for this species as well. Panel traps were deployed along transects at each of five field sites in May 2010 to test attraction of native beetle species to a suite of cerambycid pheromone components, including monochamol, 3-hydroxyhexan-2-one, (2R*,3R*)- and (2R*, 3S*)-2,3-hexanediol, racemic (E/Z)-fuscumol, and (E/Z)-fuscumol acetate. In total, 209 adult M. s. scutellatus (136 females, 73 males) and 20 M. notatus (16 females, four males) were captured, of which 86 and 70%, respectively, were captured in traps baited with monochamol (means significantly different). Analysis of headspace volatiles from adult M. s. scutellatus by coupled gas chromatography-mass spectrometry and gas chromatography-electroantennogram detection confirmed that monochamol was produced only by males. Monochamol was not found in headspace extracts from adult M. notatus. This study provides further evidence that monochamol is a pheromone component common to several species in the genus Monochamus. The pheromone component should prove useful for monitoring native species for management purposes or conservation efforts, and for quarantine monitoring for exotic species.
Journal of Economic Entomology 12/2012; 105(6):2029-34. · 1.70 Impact Factor
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ABSTRACT: The sex pheromone of Stenoma catenifer was evaluated in commercial avocado orchards in Guatemala to determine operational parameters, such as optimal lure type, trap height, trap density and estimates of the distances that male moths fly. Of four pheromone dispensers tested, gray and white rubber septa were of equal efficacy, whereas 1-ml low-density polyethylene vials and 2×3-cm polyethylene ziplock bags were least efficacious. The height at which wing traps were hung did not significantly affect the number of adult male S. catenifer captured. For monitoring S. catenifer, these data suggest that the pheromone should be dispensed from gray rubber septa in wing traps hung inside the tree canopy at 1.75 m, a height convenient for trap placement and monitoring. Mark-recapture studies of male S. catenifer indicated that, on average, males flew 67 m in one night. However, it is likely that this is an underestimate of the distance that male moths are capable of flying in a single night. Probabilistic modeling of S. catenifer capture data from different numbers of pheromone traps deployed in seven commercial avocado orchards of varying sizes and infestation levels suggested that 10-13 randomly deployed traps per orchard for a 7-day period are needed to detect at least one male S. catenifer with 90% confidence. These data provide sufficient information to develop effective protocols for using the S. catenifer pheromone to detect and monitor this pest in countries with endemic populations that are exporting fresh avocados, and for quarantine detection and incursion monitoring in countries receiving avocado imports from high risk areas.
Bulletin of entomological research 11/2010; 101(2):145-52. · 1.58 Impact Factor
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ABSTRACT: House flies, Musca domestica L., were collected in copula over two summers from six dairies located in three climatically distinct regions in the U.S.A. southern California, Minnesota and Georgia. Ages of males and females from a total of 511 mating pairs were estimated using pterin analysis. Cuticular hydrocarbon profiles and gonotrophic ages of females also were evaluated. Mean age of mating males ranged from 54 to 102 degree-days (DD) (4-10 days based on field air temperatures), depending on the farm. Very young males (< 10-20 DD) and old males (> 200 DD) were rare in mating pairs. Mean female age at mating ranged from 20 to 46 DD (2.5-4 days). All mating females had eggs in the early stages of vitellogenesis and 99.2% were nulliparous. However, some older and parous females were collected, demonstrating that re-mating can occur in the field. Head width measurements of mating pairs suggested that assortative mating by size did not occur. The cuticular hydrocarbon profiles of females were determined, with emphasis on (Z)-9-tricosene (muscalure). Overall, only 55% of mating females had detectable amounts (> 4 etag per fly) of (Z)-9-tricosene. Of the females that had detectable (Z)-9-tricosene, variation in amount per female was high in all fly populations, and thus was not statistically related to the size or age of the mating female. The proportion of mating females with detectable levels of (Z)-9-tricosene varied by geographic region. Seventy-one, 63, and 27% of females from southern California, Minnesota and Georgia had detectable amounts of (Z)-9-tricosene. Principal components analysis of the eight most abundant hydrocarbons from mating females, by state, revealed state-level distinctiveness of hydrocarbons in house fly populations, which may reflect genetic variation associated with environmental stresses in those geographical zones.
Medical and Veterinary Entomology 12/2009; 23(4):426-42. · 1.91 Impact Factor
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ABSTRACT: We report the identification and field bioassays of a major component of the male-produced aggregation pheromone of Anelaphus inflaticollis Chemsak, an uncommon desert cerambycine beetle. Male A. inflaticollis produced a sex-specific blend of components that included (R)-3-hydroxyhexan-2-one, (S)-2-hydroxyhexan-3-one, 2,3-hexanedione, and (2R,3R)- and (2R,3S)-2,3-hexanediols. Field trials with baited bucket traps determined that the reconstructed synthetic pheromone blend and (R)-3-hydroxyhexan-2-one alone attracted adult A. inflaticollis of both sexes, with significantly more beetles being attracted to the blend. We conclude that (R)-3-hydroxyhexan-2-one is a major pheromone component of A. inflaticollis, and our results suggest that one or more of the minor components may further increase attraction of conspecifics. Scanning electron microscopy showed that male A. inflaticollis have pores on the prothorax that are consistent in structure with sex-specific pheromone gland pores in related species. Males also displayed stereotyped calling behavior similar to that observed in other cerambycine species. This study represents the first report of volatile pheromones for a cerambycine species in the tribe Elaphidiini.
Environmental Entomology 10/2009; 38(5):1462-6. · 1.56 Impact Factor
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ABSTRACT: Large body size confers a reproductive advantage to adults of the wood-boring beetle Phoracantha semipunctata (F.) (Cerambycidae: Cerambycinae: Phoracanthini). Larvae of this species feed subcortically in stressed and dying eucalypt trees and logs. We evaluated the influence of the larval environment on larval performance and adult body size by manipulating the post-felling age of host logs (from freshly cut to 2-weeks-old) and the density of colonizing neonates (low density with minimal competition for resources vs. high density with intense competition). Adult beetles emerged in greater numbers from logs that had been subjected to the aging treatment which reduced bark moisture content and favored colonization by neonates. Survival was greatest in larger logs having lower densities of neonates, but was greatly diminished in all treatments by mortality during pupation. Development time varied from 2 months to more than a year and was shortest in smaller logs having high densities of larvae. The size of adult beetles emerging from a log was not influenced by larval density, but was positively correlated with the age of logs when the neonates colonized, and log size. These findings suggest that the optimal developmental conditions for P. semipunctata larvae, in terms of larval performance and adult body size, are available in large, aged host logs having low densities of larvae. Manipulation of the larval environment in this study resulted in a considerable variation in adult body size, but large individuals were relatively more common in the wild population that was the source of neonates for the experiment. Potential body size may have been constrained by our use of only one host species and a narrow range of log dimensions.
Entomologia Experimentalis et Applicata 12/2004; 114(1):25 - 34. · 1.53 Impact Factor
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ABSTRACT: The male-produced sex pheromone of the red-shouldered stink bug, Thyanta pallidovirens (Stål) (Hemiptera: Pentatomidae) consists of a blend of methyl (E2,Z4,Z6)-decatrienoate (E2,Z4,Z6-10:COOMe), and the sesquiterpenes (+)-alpha-curcumene, (-)-zingiberene, and (-)-beta-sesquiphellandrene. In laboratory bioassays, sexually mature males attracted sexually mature females but not males, and females did not attract either sex. Extracts of volatiles collected from sexually mature males contained compounds not present in extracts from females or sexually immature males, and male-produced extract was attractive to females. Biological activity was lost when the extract was fractionated, indicating that the pheromone consisted of at least two components having different chemical properties. Individually, pheromone components were not attractive to females, but E2,Z4,Z6-10:COOMe in combination with at least one of the three male-produced sesquiterpenes was attractive. The presence of more than one sesquiterpene in the blend did not increase attraction, indicating redundancy in the pheromone signal. Male extract was as attractive as a blend reconstructed from synthesized compounds, indicating all biologically active components had been identified. In bioassays conducted at dusk in a 1- x 1- x 1-m screen field cage, females were attracted to synthetic pheromone lures. In field trials, adult female T pallidovirens were attracted to pheromone-baited traps in relatively low numbers. The profile of volatiles released by sexually mature males of a congeneric species, Thyanta accerra custator McAtee, was remarkably similar to that of male T. pallidovirens, with the exception that the former species produced (E)-2-decenal, a compound that was not found in T. pallidovirens extracts.
Journal of Chemical Ecology 10/2002; 28(9):1797-818. · 2.66 Impact Factor
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ABSTRACT: Two species of cerambycid beetles that attack eucalypts, Phoracantha semipunctata (Fabricius) and P. recurva Newman, have been accidentally introduced from Australia into most regions of the world in which their hosts have been planted. The beetles cause extensive mortality in plantations and landscape plantings of the trees. Management programmes have focused on integration of silvicultural practices, host plant resistance and biological control. To rear and release natural enemies of the larval stages of the beetles in California, mass rearing protocols for continuous production of two species of parasitoids have been developed. The methods described represent the first long-term and large-scale techniques for mass rearing parasitoids of any wood-boring cerambycid species. In addition to providing large numbers of parasitoids for releases, the mass rearing effort has also provided large numbers of parasitoids for fundamental studies of their biology and behaviour.
Bulletin of Entomological Research 05/2002; 92(2):141-6. · 1.88 Impact Factor
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ABSTRACT: For the first 150 years following their introduction, eucalypts planted in the California landscape were free of both insect pests and diseases. In the last 15 years, numerous herbivorous insect species have been introduced accidentally into the State and have caused significant damage to the trees. Several of these species, e.g. Phoracantha semipunctata (Fabricius), Phoracantha recurva Newman (Coleoptera: Cerambycidae) and Gonipterus scutellatus Gyllenhal (Coleoptera: Curculionidae), have also been introduced into other parts of the world where eucalypts are grown, whereas others, e.g. Glycaspsis brimblecombei Moore (Hemiptera: Spondyliaspidae) and Eucalyptolyma maideni Froggatt (Hemiptera: Spondyliaspidae), are currently restricted to California and Australia. Research programmes have provided management solutions to individual pest problems, but as more pest species are introduced, these solutions must be integrated across broad geographic, horticultural, and economic scales, in a systems approach.
Bulletin of Entomological Research 05/2002; 92(2):147-52. · 1.88 Impact Factor
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ABSTRACT: The reproductive behaviors of the stink bugs Chlorochroa ligata and C. uhleri were studied in the laboratory. Adults of both species became sexually mature about 12-14 days after the final molt, and both sexes mated multiple times during their lifetimes. The mean duration of copulation was 54 +/- 24 min for virgin bugs and 46 +/- 33 min for experienced bugs for C. ligata and 78 +/- 55 min for field-collected C. uhleri of unknown mating status. Male C. ligata were found to transfer a significant fraction of their body mass (19%) to females during mating. Sexually mature C. uhleri males produced three sex-specific compounds, methyl (R)-3-(E)-6-2,3-dihydrofarnesoate, methyl (2E,6E)-farnesoate, and methyl (E)-5-2,6,10-trimethyl-5,9-undecadienoate, in a ratio of 100:0.9:0.6. These three compounds were also produced by sexually mature male C. ligata in a ratio of 100:0.5:0.4. Identifications of the compounds were confirmed by synthesis. Production of the male-specific compounds peaked in late afternoon to early evening, coincident with the peak period of reproductive activity. Laboratory and field bioassays demonstrated that female bugs were attracted to odors from live males and to reconstructed blends of the male-specific compounds.
Journal of Chemical Ecology 11/2001; 27(10):2067-95. · 2.66 Impact Factor
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ABSTRACT: Sexually mature virgin adult males of the green stink bug, Acrosternum hilare attracted sexually mature virgin adult females in laboratory bioassays using a vertical Y-tube. There was no indication that males attracted other males, or that females attracted either sex. These results suggested that A. hilare males produce a sex pheromone. Extracts of odors collected from sexually mature males contained compounds that were not present in extracts from females or sexually immature males. (4S)-Cis-(Z)-bisabolene epoxide ((4S)-cis-Z-BAE) was the major sex-specific component of the extract. The crude extract was attractive to female A. hilare, but when separated into four fractions, only the portion containing (4S)-cis-Z-BAE and the minor component (4S)-trans-Z-BAE was attractive to females. This fraction was as attractive as the crude extract, suggesting that the former contained all the pheromone components. Neither synthetic (4S)-cis-Z-BAE nor (4S)-trans-Z-BAE alone was attractive to females, but a 95:5 cis:trans blend, mimicing the ratio naturally produced by males, was attractive to females in Y-tube bioassays. Bioassays in a field cage showed that significantly more A. hilare females were attracted to cotton string lures treated with 1 mg of a 95:5 blend of (4S)-cis-Z-BAE and (4S)-trans-Z-BAE placed inside a bouquet of alfalfa than to an alfalfa bouquet containing a pentane-treated control. In field cage studies, attraction of females was greatest during the late afternoon and evening hours, and female A. hilare approached the synthetic pheromone source almost exclusively by walking.
Journal of Chemical Ecology 10/2001; 27(9):1821-39. · 2.66 Impact Factor
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ABSTRACT: The sex attractant pheromone blend of Hemileuca maia (Lepidoptera: Saturniidae) from the vicinity of Baton Rouge, Louisiana, has been identified. The major component of the blend is (E10,Z12)-hexadeca-10,12-dienal (E10,Z12-16:Ald), in combination with the minor components (E10,Z12)-hexadeca-10,12-dien-1-ol (E10,Z 12-16:OH), and (E10,Z12)-hexadeca-10,12dien-1-yl acetate (E10,Z12-16:Ac). Ratios of the compounds in extracts of female pheromone glands varied around a mean of 100:7.4:6.3. None of the three components were attractive to male moths when tested as single components. Several other compounds were tentatively identified from female pheromone gland extracts, including E10,E12-16:Ald, E10,E12-16:OH, and E10,E12-16:Ac, but addition of these components, either alone or in combination, at biologically relevant rates, did not significantly increase the attractiveness of lures. The saturated analogs, hexadecanal, hexadecanol, and hexadecyl acetate, also were identified in gland extracts, but had no apparent effect as pheromone components.
Journal of Chemical Ecology 08/2001; 27(7):1409-22. · 2.66 Impact Factor
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ABSTRACT: The reproductive behavior of the stink bug Chlorochroa sayi was studied in the laboratory. There was a sexual maturation period of about 10 days before bugs began mating. Sexually mature adult bugs engaged in courtship consisting of antennation and head-butting of the female by the male, before the female adopted a receptive posture and copulation occurred. Both sexes mated multiple times during their life-spans, with the mean duration of copulations of virgin bugs (42.3 +/- 19.6 min) and experienced bugs (37.3 +/- 28.4 min) being similar. Most matings were initiated in the late afternoon or evening, when pheromone production by males was greatest. Males transferred sperm and nutrients constituting about 17% of their body weight to females during mating. Three male-specific components, methyl geranate, methyl citronellate, and methyl (E)-6-2,3-dihydrofarnesoate in a ratio of 100:0.45:1.6, were first detected in volatiles collected from male bugs on green beans about 9-12 days after the final molt to the adult stage. In vertical Y-tube bioassays, females were attracted to odors from mature male bugs, and to a blend of the three male-produced components. Low numbers of females also were attracted in field trials with the three-component blend. The relatively weak attraction may be a result of other, as yet unknown cues being required in addition to the pheromone, such as visual or substrate-borne vibrational cues.
Journal of Chemical Ecology 07/2001; 27(6):1177-201. · 2.66 Impact Factor
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ABSTRACT: The lepidopteran genus Saturnia has three representatives in North America, S. walterorum, S. mendocino, and S. albofasciata. (E4,Z9)-Tetradecadienal (E4,Z9-14:Ald) was identified as a sex pheromone component for all three species by combinations of coupled gas chromatography-electroantennogram detection (GC-EAD), GC-mass spectrometry (MS), and field trials. In field trials, all three species were strongly attracted to (E4,Z9-14:Ald) as a single component. Small amounts of (Z)-9-tetradecenal (Z9-14:Ald) also were found in extracts of all three species, but blends of this compound with E4,Z9-14:Ald were no more attractive to male moths than E4,Z9-14:Ald alone. Extracts of pheromone glands of female S. walterorum occasionally contained a third, trace compound eliciting responses from male antennae in GC-EAD experiments, but this compound was not identified. It is suggested that the three species can use the same, single components as a sex attractant because the flight period of S. albofasciata (fall) is different than that of the other two species (spring), whereas the geographic distributions of S. mendocino and S. walterorum overlap over only small portions of their ranges. Furthermore, the latter two species readily hybridize, so there may be minimal fitness cost to cross-attraction.
Journal of Chemical Ecology 05/2001; 27(4):791-806. · 2.66 Impact Factor
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ABSTRACT: In March 1994, Gonipterus scutellatus Gyllenhal, an Australian weevil that feeds on foliage of eucalypts, was discovered in Ventura County, CA. By the time of its discovery, the weevil was defoliating eucalypt trees in citrus orchard windrows. We imported, reared, and released a parasitoid of the weevil's eggs, Anaphes nitens Siscaro (Hymenoptera: Mymaridae). A. nitens was firmly established in several southern California counties by mid-1997 and was spreading in tandem with its host. The wasp has proven to be effective in suppressing weevil populations, killing >95% of weevil eggs, except possibly in areas where insecticides are applied to manage pests of field crops. A. nitens appears to be a promising biological control agent for G. scutellatus in California.
Environmental Entomology 03/2000; 29(2):369-375. · 1.56 Impact Factor
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J G Millar
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ABSTRACT: Polyene hydrocarbons and epoxides are used as pheromone components and sex attractants by four macrolepidopteran families: the Geometridae, Noctuidae, Arctiidae, and Lymantriidae. They constitute a second major class of lepidopteran pheromones, different from the C10-C18 acetates, alcohols, and aldehydes commonly found in other species. They are biosynthesized from diet-derived linoleic or linolenic acids and are characterized by C17-C23 straight chains, 1-3 cis double bonds separated by methylene groups, and 0, 1, or 2 epoxide functions. Pheromone blends are created from components with different chain lengths, numbers of double bonds, and functional groups, or from mixtures of epoxide regioisomers or enantiomers, with several examples of synergism between enantiomers. Behavioral antagonists also limit interspecific attraction, with numerous examples of antagonism by enantiomers. This review summarizes the taxonomic distribution, mechanisms used to generate unique pheromone blends, and the identification, synthesis, and biosynthesis of these compounds.
Annual Review of Entomology 02/2000; 45:575-604. · 11.45 Impact Factor
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ABSTRACT: Laboratory bioassays demonstrated that fermented infusions of dried bulrushes (Schoenoplectus acutus) strongly attracted and stimulated oviposition by gravid female Culex quinquefasciatus and Culex tarsalis. The responses of the 2 species varied with the concentration and method of preparation of the infusions, with responses generally increasing with increasing concentration. No major differences were found in the responses of either species to infusions prepared with bulrushes alone, or with bulrushes plus lactalbumin hydrolysate and brewer's yeast. Infusions remained more attractive than distilled water controls to both species for up to 8 wk. Field tests corroborated the results from the laboratory bioassays. Culex quinquefasciatus, Cx. tarsalis, and Cx. stigmatosoma egg rafts were collected from water pan traps baited with bulrush infusions. A few Culiseta incidens eggs also were collected. In multiple-choice tests using gravid female or egg traps, Cx. quinquefasciatus preferred the most concentrated bulrush infusions, whereas Cx. tarsalis preferred intermediate concentrations. Female Cx. stigmatosoma and Culiseta incidens also were attracted. Overall, these results may provide new leads towards developing synthetic chemical baits to attract bloodfed mosquitoes.
Journal of the American Mosquito Control Association 12/1999; 15(4):500-9. · 0.91 Impact Factor
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ABSTRACT: Odors were collected from the headspace above fermented infusions of Bermuda grass, which commonly are used as attractants in traps for gravid mosquitoes. Coupled gas chromatography-electroantennogram detection (GC-EAD) was used to identify 9 compounds (phenol, p-cresol, 4-ethylphenol, indole, 3-methylindole, nonanal, 2-undecanone, 2-tridecanone, naphthalene) from odor extracts that elicited significant antennal responses from antennae of gravid female Culex quinquefasciatus Say and Culex tarsalis Coquillett mosquitoes. Several of these compounds at appropriate concentrations were weakly attractive to gravid female mosquitoes in laboratory bioassays and/or stimulated more oviposition than water controls. In addition, dimethyltrisulfide, a significant component of odor extract which did not elicit strong responses from female mosquito antennae in GC-EAD assays, also appeared to stimulate oviposition at 1 concentration. A reconstituted blend of the 10 compounds resulted in much stronger and more consistent responses than individual compounds. The blend was attractive to gravid Cx. quinquefasciatus and enhanced oviposition over a range of concentrations spanning 3 orders of magnitude. One concentration of the blend also attracted gravid Cx. tarsalis and enhanced oviposition. However, at the highest concentration tested, the blend was repellent to both species. Overall, these studies demonstrated that gravid mosquitoes are attracted to oviposition sites by blends of compounds rather than by individual chemicals, and that the concentration of compounds in the odor is a critical factor in determining whether responses are positive (attractive, stimulatory) or negative (repellent, deterrent).
Journal of Medical Entomology 04/1999; 36(2):158-66. · 1.76 Impact Factor
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ABSTRACT: 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.
Bioorganic & Medicinal Chemistry 03/1996; 4(3):331-9. · 2.92 Impact Factor
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ABSTRACT: Bioassay methods for mosquito oviposition attractants and stimulants were developed and compared, using Culex tarsalis Coq. gravid females as test insects, and distilled water, dyed water, or Bermuda grass infusions as the test stimuli. Bioassays with sticky screens covering jars containing volatile test stimuli or with colorless and odorless Triton X100 surfactant in the aqueous oviposition medium demonstrated that gravid mosquitoes were attracted to distilled water, with the attraction increased by the addition of dye, grass infusion, or the steam distillate of grass infusion to the water. A variation of the sticky screen bioassay was used to demonstrate that the grass infusion also contained oviposition stimulants. A forced oviposition bioassay was minimally useful, because it failed to discriminate between a solution known to contain oviposition stimulants and a distilled-water control. Overall, the bioassays developed can be used to distinguish between oviposition attractants and stimulants, a distinction that cannot be made by simply counting egg rafts.
Journal of Medical Entomology 08/1995; 32(4):475-83. · 1.76 Impact Factor
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ABSTRACT: Fermented infusions of organic matter were tested for their effects on Culex tarsalis oviposition. Bermuda grass infusion and polluted water collected from a natural oviposition site (La Brea tar pits, CA) enhanced oviposition rates, but an alfalfa infusion and water from a 2nd natural oviposition site (Prado Basin, CA) did not. Bermuda grass infusion was fractionated by dialysis and filter sterilization. Crude Bermuda grass infusion, and fractions of the infusion containing large molecules (> 12,000 daltons), particulates, and microorganisms significantly increased oviposition rates compared to distilled water controls. The fraction containing small molecules was no better than a distilled water control, suggesting that small molecules are not involved in oviposition stimulation in this species. However, using the egg raft counting bioassay, the possibility that the small molecules fraction contained oviposition attractants could not be ruled out. Overall, our experiments suggest that results obtained with the egg raft counting bioassay, which has been used frequently to screen for oviposition attractants, should be interpreted with caution. High oviposition rates in this bioassay may be due to responses to factors such as nonvolatile, contact oviposition stimulants rather than to volatile attractants.
Journal of the American Mosquito Control Association 04/1995; 11(1):21-8. · 0.91 Impact Factor
