Female-produced Sex Pheromone Research Articles

Sex pheromone production and perception in European corn borer moths is determined by both autosomal and sex-linked genes

Inheritance patterns for sex pheromone production in females, pheromone detection on male antennal olfactory receptor cells, and male pheromone behavioral responses were studied in pheromonally distinct populations of European corn borers from New York State. Gas chromatographic analyses of pheromone glands, single sensillum recordings, and flight tunnel behavioral analyses were carried out on progeny from reciprocal crosses, as well as on progeny from subsequent F(2) and maternal and paternal backcrosses. The data show that the production of the female pheromone blend primarily is controlled by a single autosomal factor, that pheromone-responding olfactory cells are controlled by another autosomal factor, and that behavioral response to pheromone is controlled by a sex-linked gene. F(1) males were found to possess olfactory receptor cells that give spike amplitudes to the two pheromone isomers that are intermediate to those of the high and low amplitude cells of the parent populations. Fifty-five percent of the F(1) males tested responded fully to pheromone sources ranging from the hybrid (E)-11-tetradecenyl acetate/(Z)-11-tetradecenyl acetate (E/Z) molar blend of 65:35 to the E/Z molar blend of 3:97 for the Z morph parents, but very few responded to the E/Z molar blend of 99:1 for the E morph parents. Data on the inheritance patterns support speculation that the Z morph is the ancestral and that the E morph is the derived European corn borer population.

Identification of female-produced sex pheromone from banded cucumber beetle,Diabrotica balteata leconte (Coleoptera: Chrysomelidae)

A sex pheromone produced by female banded cucumber beetle adults,Diabrotica balteata LeConte, was isolated from volatiles trapped on Porapak Q and identified as 6,12-dimethylpentadecan-2-one. The structure was elucidated by spectroscopic analyses and confirmed by synthesis. The synthesized racemic compound was equal to the purified natural pheromone in eliciting responses by banded cucumber beetle males to field traps. A doseresponse characteristic was demonstrated for the racemic material formulated on filter paper or rubber septa and placed in field traps. The absolute configuration at the C-6 and C-12 positions was not established.

Role of female-produced sex pheromone in behavioral reproductive isolation betweenTrichoplusia ni (H�bner) andPseudoplusia includens (Walker) (Lepidoptera: Noctuidae, plusiinae)

In laboratory flight tunnel bioassays, response rates of male cabbage looper,Trichoplusia ni (Hübner), to female soybean looper,Pseudoplusia includens (Walker), were similar to response rates of maleT. ni to conspecific females for plume tracking and source contact. Male soybean loopers, however, exhibited a greatly reduced response to female cabbage loopers compared to conspecific females. Similar differences were observed in male responses to extracts of female abdominal tips. Studies of flight tunnel responses of male soybean loopers to the different chemicals known to be components of the female cabbage looper sex pheromone indicated that the reduction in response was due to inhibitory effects of (Z)-5-dodecen-1-ol acetate and (Z)-9-tetradecen-1-ol acetate, when added singly to (Z)-7-dodecen-1-ol acetate (major component of both species) at release rates and at ratios close to those observed in female cabbage loopers.

DETERMINATION OF THE SEX-PHEROMONE COMPONENTS OF CHEIMOPHILA SALICELLA (LEPIDOPTERA: OECOPHORIDAE), A PEST OF BLUEBERRY IN BRITISH COLUMBIA

AbstractThe female-produced sex pheromone Cheimophila salicella (Hbn.) was found to be a mixture of E-11-tetradecenyl acetate, E-11-tetradecen-1-ol, tetradecyl acetate and E-11-tetradecenal, as determined by chemical analyses and field-trapping results. Capillary gas-liquid chromatography of individual female tip washes indicated relative ratios of 100:15:10:2. Field-trapping experiments showed the E-11 acetate to be essential and the E-11 aldehyde to be a powerful synergist for trapping of male moths.

Ethyl (Z)-9-hexadecenoate a sex pheromone ofSyndipnus rubiginosus, a sawfly parasitoid

A female-produced sex pheromone ofSyndipnus rubiginosus Walley (Hymenoptera: Ichneumonidae), a parasitoid of the yellowheaded spruce sawfly,Pikonema alaskensis (Rohwer) (Hymenoptera: Tenthredinidae), was isolated and identified from hexane extracts of 250 virgin females. Column chromatography (Florisil), gas chromatography, mass spectrometry, high performance liquid chromatography, and ozonolysis indicated the structure was ethyl (Z)-9-hexadecenoate. The optimum male response is at 300-1000 ng (3-10FE). No cross-attraction betweenS. rubiginosus and the sympatric sawfly parasitoidS. gaspesianus (Provancher) could be demonstrated.

Induction of female sex pheromone production in male houseflies by ovary implants or 20-hydroxyecdysone

Implanting ovaries or injecting 20-hydroxyecdysone into male houseflies induced sex pheromone production, including (Z)-9-tricosene (muscalure), 9,10-epoxytricosane and (Z)-14-tricosen-10-one, which normally occurs only in vitellogenic females. Control males did not produce detectable amounts of these compounds. Injection of 20-hydroxyecdysone (5 μg/insect per day) for 3 days resulted in the accumulation of 1.81 μg/insect of ( Z)-9-tricosene, 0.97 μg/insect of 9,10-epoxytricosane and 0.12 μg/insect ( Z)-14-tricosen-10-one. Multiple injections of 20-hydroxyecdysone at doses as low as 50 ng resulted in the accumulation of 23:1, C 23 epoxide and C 23 ketone; shifted the distribution of label within the alkenes from 27:1 to 23:1 and decreased the amount of label in the hydrocarbon fractions as alkenes. Structures of the C 23 alkene and epoxide produced by the males were verified by gas chromatography-mass spectrometry. Radioactivity from [1- 14C] acetate was incorporated into the C 23 alkene, epoxide and ketone in male insects after ovaries were implanted or they were injected with 20-hydroxyecdysone. Synthesis of the C 23 pheromone components decreased rapidly within several days after the administration of 20-hydroxyecdysone ceased, indicating that the enzymes involved in sex pheromone production were not permanently induced by hormone treatment. Ecdysone was also effective in initianing pheromone production in males, whereas inokosterone and cholesterol were not effective. Data presented demonstrate that male houseflies possess the metabolic capability to produce the sex pheromone components, and this suggests that 20-hydroxyecdysone alters the production of cuticular hydrocarbons such that the C 23 sex pheromone components become major products.

Identification of a female-produced sex pheromone from the southern corn rootworm,Diabrotica undecimpunctata howardi Barber

A sex pheromone has been isolated and identified from virgin females of the southern corn rootworm (SCR),Diabrotica undecimpunctata howardi Barber. The synthesized compound, 10-methyl-2-tridecanone was shown to be attractive to males of the SCR, and also to males ofD. u. undecimpunctata Mannerheim, the western spotted cucumber beetle (WSCB), and ofD. u. duodecimnotata in Mexico. Males of both the SCR and the WSCB strongly preferred theR over theS enantiomer. The resolved enantiomers were not tested againstD. u. duodecimnotata.

Temperature-mediated sex pheromone production and response of the American cockroach

Temperature affects the production of and response to sex pheromone by the American cockroach. Female sex-pheromone production is directly related to acclimation temperature and rapidly decreases 1 week after acclimation to lower temperatures. Production decreases slightly between weeks 1 and 2 and remains constant thereafter. Phermone-release rates are not affected by substrate temperature. Male response to a 1 ♀-equivalent hr pheromone dose is also temperature dependent. Maximal response was obtained at 26.7°C. Acclimated males were able to perceive pheromone (EAG technique) and capable of movement at lower temperatures (10°C), suggesting central nervous system inhibition.

Identification of a female-produced sex pheromone of the western corn rootworm

A sex pheromone has been isolated and identified from virgin females of the western corn rootworm (WCR),Diabrotica virgifera virgifera LeConte. The synthesized compound, racemic 8-methyl-2-decanol propanoate, was equal in attraction to the natural pheromone when tested in the field as a trap bait against three taxa ofDiabrotica known to respond to pheromone extracts from female WCR. Five taxa (D. virgifera virgifera; D. virgifera zeae Krysan and Smith, Mexican corn rootworm;D. longicornis barberi Smith and Lawrence, northern corn rootworm;D. longicornis longicornis (Say); andD. porracea Harold) were attracted to traps baited with 8-methyl-2-decanol propanoate. The response of male northern corn rootworms (NCR) in the field peaked at a relatively low concentration of 8-methyl-2-decanol propanoate and then was severely reduced at the higher concentrations tested. Conversely, the response of male WCR in the field continued to increase up to the highest dose tested.

Prediction and monitoring of outbreaks of orchard pests

New Zealand orchards are attacked by a complex of insect and mite pests. Repeated sprays of broad-spectrum insecticides are maintained so that the large volume of exported fruit meets stringent quarantine requirements. The nil tolerance of insect infestation places severe restraints on programmes which attempt to reduce spraying through monitoring pest status in orchards. Considerable progress has been achieved in the integrated control of mite pests in commercial orchards. This technique is reviewed. It includes monitoring of the status of pest mites and their insecticide-resistant predators so as to minimise the application of acaricides. Female-produced sex pheromones have been determined for several insects attacking fruit. The use of pheromone traps in monitoring insect activity either to reduce the frequency of insecticide application or to improve their timing is discussed.

Evidence for a multicomponent sex pheromone in the yellowheaded spruce sawfly

The existence of a female-produced sex pheromone in the yellowheaded spruce sawfly,Pikonema alaskensis (Rohwer) (Hymenoptera: Tenthredinidae) was demonstrated by field and greenhouse bioassays. Virgin females, their empty cocoons (with which they were confined during handling procedures), and the hexane extract of these cocoons were attractive in the field. The only Florisil fraction of this extract consistently attractive by itself was that eluted with hexane, but three, more polar fractions (eluted with 5%, 25%, and 50% ether in hexane) each synergized the hexane fraction, increasing bioassay responses 10-30 times. Fractions derived directly from virgin females yielded comparable results. The greenhouse data corroborated the field data, except that the 5% ether-hexane fraction, while very synergistic in the field, was consistently inactive in the greenhouse.

Female-produced sex pheromone inBrachymeria lasus andB. intermedia [Hym.: Chalcididae

A female-produced sex pheromone in these chalcid parasitoids serves to aid mate recognition by the male. InBrachymeria lasus (Walker) male response to the pheromone remains constant with increasing male age, but pheromone activity declines with age in females. The active space of the pheromone is approximately 3 cm; at greater distances males do not respond and continue random movements. The site of pheromone production in these species remains undefined, although the thorax elicited greatest male courtship response, and the Dufour's gland area the highest % of male sensory responses.

Evidence for a sex pheromone in the hide beetle,Dermestes maculatus (De Geer) (Coleoptera: Dermestidae)

Adults of the hide beetle,Dermestes maculatus (De Geer), were shown to have a female-produced sex pheromone which excited males. Male response was positively correlated with increasing age, but females produced a higher level of pheromone at 6–8 days of age than at younger or older ages. Extractable female pheromone and male response varied over the photophase with peak values that occurred during the latter hours. Quantitative bioassay indicated that the 50% male response level (RD50) would be elicited by a pheromone exposure of 0.01 female equivalents (FE). Females extracted 24 hr after mating had a lower level of extractable pheromone than did virgin females of the same age.

MONITORING FLIGHT PATTERNS OF MALE SAN JOSE SCALE (HOMOPTERA: DIASPIDIDAE)

The presence of female-produced sex pheromones in diaspidid scales has been known for several years, and was recently documented for the San Jose scale, Quadraspidiotus perniciosus (Comstock) (Rice 1974). This paper reports the results of 3 years of seasonal monitoring for male San Jose scale in an attempt to determine how and when this pheromone might be used as a monitoring technique in pest management programs in deciduous fruit orchards. These studies were conducted at the San Joaquin Valley Agricultural Research Center near Parlier, Fresno County, Calif.

Behavioral responses of maleArgyrotaenia velutinana (Lepidoptera: Tortricidae) to components of its sex pheromone

Males of the redbanded leafroller,Argyrotaenia velutinana (Walker) (Lepidoptera: Tortricidae), were studied for their behavioral responses in laboratory olfactometers and in the field to the 3 components of the female-produced sex pheromone:cis-11-tetradecenyl acetate (c11–14∶Ac),trans-11-tetradecenyl acetate (t11–14∶Ac), and dodecyl acetate (12∶Ac). Dodecyl acetate, when evaporated with c11–14∶Ac (8%trans) in the field, modified the behavior of feral males nearby the chemical source, causing an increase in the frequency of landing and close approach to the pheromone dispenser. Apparently, an inflight behavioral modification concerning landing or not landing occurs within 60 cm of the source and is mediated by 12∶Ac. In laboratory olfactometers, c11–14∶Ac (8%trans) demonstrated a lower threshold for male activation than pure c11- and t11–14∶Ac and blends of the two isomers. Additionally, over a wide range of dosages, males responded with optimum wing-fanning response to c11–14∶Ac (8%trans) compared to pure c11–14∶Ac, c11–14:Ac (30%trans), and pure t11–14∶Ac, suggesting that thecis∶trans ratio rather than absolute amounts of either isomer, is a crucial factor in eliciting male response. When presented with c11–14∶Ac (8%trans) (1∶1), dodecyl acetate caused a significant prolongation of wing-fanning over c11–14∶Ac (8%trans) alone and resulted in a greater percentage of males moving upwind to the source. Since the increase in wing-fanning and orientation occurred at higher concentrations of the 3-component mixture, the effect of 12∶Ac in the laboratory may reflect the close-range role of 12∶Ac in the field.

Electroantennogram responses of the male moth, Argyrotaenia velutinana to mixtures of sex pheromone components of the female

Electroantennogram (EAG) responses were recorded from male redbanded leafroller moth, Argyrotaenia velutinana, antennae using mixtures of the three female-produced sex pheromone components: cis-11-tetradecenyl acetate, trans-11-tetradecenyl acetate, and dodecyl acetate (12:Ac). Binary mixtures containing 3%, 8%, and 15% trans in cis elicited significantly higher amplitude responses than other isomeric mixtures as well as pure cis and trans alone. The higher responses to such mixtures were less than additive at high dosages and additive at lower dosages. Receptor adaptation studies using the two isomers support a previous single unit study demonstrating the presence of at least two functionally different receptor sites on male A. velutinana antennae; adaptation to an airstream containing one isomer did not eliminate response to the opposite isomer presented concurrently. An airstream containing the third component, 12:Ac, caused a significant slowing of the recovery rate during the entire recovery period of EAG responses to cis but not trans, suggesting that a possible temporal modulation of neuronal response by 12:Ac may be a means of coding for this component by antennal sensory neurons.

TEMPERATURE MODIFICATION OF MALE SEX PHEROMONE RESPONSE AND FACTORS AFFECTING FEMALE CALLING IN HOLOMELINA IMMACULATA (LEPIDOPTERA: ARCTIIDAE)

AbstractIn Holomelina immaculata (Reakirt) periodicity of male attraction to synthetic 2-methylheptadecane, the female-produced sex pheromone, is modified by temperature cues. In the field this response interval occurs from approximately sunset to about 4 h after sunset on a warm day and night (30° to 17 °C) and for the 2 h prior to sunset on a cool day and night (23° to 16 °C).In laboratory studies at 24 °C female H. immaculata placed in continual scotophase have an endogenous calling rhythm, but they are apparently inhibited from calling by constant photophase. In 16:8 or 12:12 light–dark cycles at 24 °C calling occurs from the 2nd to the 6th hour of scotophase, whereas at 15 °C calling takes place from the initiation to the 5th hour of scotophase. The critical cues governing initiation of calling behaviour are lights-off or a temperature decrease cue, and a temperature decrease signal overrides the apparent inhibitory effect of continual photophase.

Reproductive Biology of the Cigarette Beetle, Lasioderma serricorne1 2. Ovarian Development and Female Sexual Maturity2,3,4

The ovaries of Lasioderma serricorne (F.) females are comprised of 12–20 telotrophic ovarioles (6–10 per ovary). Ovarian development was measured on an arbitrary scale from 0 to 7. The first 3 stages, 0–2, were characteristic of pre-imaginal specimens. Stages 3–7 were associated with adult beetles. Stage 7 was represented by mature oocytes, and at 27±2°C, 97.5% of the experimental females had attained this level of development by 4–5 days of age. In behavioral tests, females younger than 10–12 hr of adult age did not stimulate copulatory attempts by sexually mature males, whereas older females did elicit male mating behavior. Females were generally not receptive to male copulatory attempts before 56–64 hr of age. Female receptivity, as determined by the percentage of females inseminated, reached a maximum at about 4–5 days of age. Physiological (ovarian) and behavioral (mating receptivity) maturity were thus coincident at 4–6 days of age, a time at which female sex pheromone production is maximal and adult emergence from the pupal cell usually occurs.

Sex Pheromones of Lepidoptera. XXVIII. Factors Modifying the Release Rate and Extractable Quantity of Pheromone from Females of Trichoplusia ni (Noctuidae)1

The following 3 aspects of female sex pheromone production and release were quantitatively studied, using a laboratory colony of Trichoplusia ni (Hubner) : the amount of pheromone contained on and in the whole gland, the amount contained on the gland surface only, and the amount evaporated into the air from the gland surface after the gland was everted (exposed to the air). The whole-gland content and the evaporation rate were strongly influenced by female age and by unexplained population variation over several weeks and months. Time of day had no pronounced effect on wholegland content or evaporation rate. In an air stream moving 10 cm per second, mean evaporation rate was 7 nanograms per minute during the first 10 minutes following gland eversion. This evaporation rate rapidly depleted the amount of pheromone initially found on the gland surface (about 48 nanograms), and a considerably reduced rate occurred during the second 10 minutes of gland eversion. Evaporation took place more rapidly in an air stream moving 100, as opposed to 10, cm per second.

Pheromone Concentrations Required to Elicit Successive Steps in the Mating Sequence of Males of the Light-Brown Apple Moth, Epiphyas postvittana1

Responses of male Lepidoptera to female-produced sex pheromones consist of a succession of behavioral steps. Quantitative bioassays of these pheromones have relied on the determination of the relationship between pheromone concentration and the frequency of occurrence of 1 of these steps (Bartell and Shorey 1969, Shorey et al. 1964). It has been assumed that the initial step in the behavioral sequence has the lowest threshold of pheromone concentration and that each successive step has a higher threshold than the preceding one (Schwinck 1955, Guerra 1968, Traynier 1968). We report here a series of experiments which demonstrate the validity of this assumption.