Female Sex Pheromone Gland Research Articles

Sex Pheromone of the Blister Coneworm Moth, Dioryctria clarioralis (Lepidoptera: Pyralidae)

Male Dioryctria clarioralis moths are attracted to a synthetic blend of 30 µg Z9–14:OAc, 12% E 9–14:OAc, and 5 to 10% Z11–16:OAc. The two tetradecenyl acetates have been characterized from the female sex pheromone gland. Due to the small quantities of pheromone stored by the female (<0.5 ng per female) we were not able to isolate Z11–16: OAc. Dodecyl acetate was identified from gland extracts yet it did not appear to be necessary for attracting males to pheromone traps. Males of a sympatric species, D. merkeli , were attracted to pheromone traps containing blends of the two 14-carbon acetates (0 to 15% E ), yet were not attracted to traps baited with virgin D. clarioralis , suggesting that an additional component(s) was used by D. clarioralis . Temporal (diel and seasonal) and pheromonal niche dimensions for four sympatric species of Dioryctria are discussed.

Behavioral responses of maleHeliothis zea moths in sustained-flight tunnel to combinations of 4 compounds identified from female sex pheromone gland

Each of the four compounds that have been identified from sex pheromone glands ofHeliothis zea female moths was examined for its ability to elicit sexual responses from male moths in a flight tunnel. Males flew upwind to (Z)-11-hexadecenal alone, but greater levels of behavioral activity were evoked with the addition of (Z)-9-hexadecenal to the treatment. Addition of hexadecanal or (Z)-7-hexadecenal to the initial two components had no effect in raising the behavioral response of the males in the flight tunnel whether added singularly at both the normal gland-emission ratio or at varying ratios or in combination at the normal ratio. Live, calling females elicited levels of sexual activity from males not significantly different from that elicited by the mixture of (Z)-11- and (Z)-9-hexadecenal on cotton wicks.

Behavioral responses of maleHeliothis virescens in a sustained-flight tunnel to combinations of seven compounds identified from female sex pheromone glands

Each of the seven compounds that have been identified from femaleHeliothis virescens sex pheromone glands was examined for its ability to elicit sexual responses from male moths in a flight tunnel. The two compounds initially described as pheromone components, (itZ)-11-hexadecenal and (itZ)-9-tetradecenal, were necessary for behavioral activity to occur. Of the remaining five compounds, hexadecanal was most consistent in elevating behavioral activity of males when it was added to treatments. Live, calling females elicited greater sexual activity from males than did the 7-compound mixture on rubber septa.

Female Sex Pheromone Glands in the Parasitic Wasps, Genus Apanteles

Female Sex Pheromone Glands in the Parasitic Wasps, Genus Apanteles

Quinone Inhibition of Sex Pheromone Activity in the Ticks Dermacentor andersoni Stiles and Dermacentor variabilis (Say)

Disruption of sex pheromone activity in female Rocky Mountain wood ticks, Dermacentor andersoni Stiles, and American dog ticks, Dermacentor variabilis (Say), was achieved by treatment with the quinones para-benzoquinone and menadione. The most effective treatments were those administered by inoculation to unfed, mature, adult females prior to feeding. Inoculation of p-benzoquinone was also effective when administered to feeding ticks, from 2 to 5 days after they had attached, though not to the same extent as when it was given to unfed ticks. Decreases in sex pheromone activity were also observed with D. andersoni females, but not D. variabilis females, allowed to feed on rabbits receiving menadione daily by oral administration. Histochemical studies and electron microscopy revealed loss of neutral lipid secretory droplets in the pheromone glands, but no damage to gland structure, following treatment with p-benzoquinone. Elemental analysis revealed more than four times as much chlorine in pheromone glands of p-benzoquinone-treated D. variabilis females than in pheromone glands from control specimens. An extract of partially fed D. variabilis females treated with p-benzoquinone before feeding contained much more 2,6-dichlorophenol than an extract of untreated, partially fed females. Evidently, the quinone affects the neutral lipid component of the female sex pheromone gland, disrupting secretion and release of pheromone to the external body surface.

Isolation and Identification of a Component of the Female Sex Pheromone Gland Attractive to Male Xylomyges curialis1

(Z)-11-Hexadecen-1-ol (Z11-16:OH) was isolated from extract of the sex pheromone gland of female Xylomyges curialis Grote (Lepidoptera: Noctuidae) and identified by gas chromatographic and by gas chromatography-mass spectrometric analysis of the parent compound, the acetate derivative, and the ozonolysis product of the acetate derivative. No other unsaturated alcohols, acetates, or aldehydes could be detected in the extract. In field tests, traps baited with synthetic Z11-16:OH effectively captured males.

Sex pheromone of the avocado pest,Amorbia cuneana (Walsingham) (Lepidoptera: Tortricidae)

The major volatile components in the extract of the female sex pheromone gland ofAmorbia cuneana consisted of (E,E)- and (E,Z)-10,12-tetradecadien-1-ol acetates. The identification was based on electroantennogram bioassay of gas Chromatographic effluent from sex pheromone gland extract, relative retention times on polar and nonpolar gas chromatographic columns, chemical degradation (ozonolysis, saponification), mass spectrometry, chemical synthetic methods, and field tests. Based on mass spectrometry and retention times by capillary gas chromatography, traces of (E)-10-tetradecen-1-ol acetate and 1-tetradecanol acetate were also present in the extract. Traps baited with a combination of synthetic (E,E)- and (E,Z)-10,12-tetradecadien-1-ol acetates caught more males than did traps baited with females.

EVIDENCE FOR NATURALLY OCCURRING, SECONDARY COMPOUNDS OF THE CODLING MOTH FEMALE SEX PHEROMONE

AbstractBioassay comparisons of gas chromatographic separations of codling moth female sex pheromone glands revealed the existence of naturally occurring compounds additional to the single, reported compound, (E, E)‐8,10‐dodecadien‐1‐o1.

Sex Pheromone Gland of the Gypsy Moth1 Parasitoid, Apanteles melanoscelus:2 Revaluation and Ultrastructural Survey

Observations of premating behavior of Apanteles melanoscelus (Ratzeburg) (Hymenoptera: Braconidae) males exposed to parts of female abdomens suggested that the sex pheromone gland of females was not Dufour's gland as previously reported but paired epidermal glands on the 8th abdominal tergum. The columnar cells of these glands contained lipid deposits, microvilli, and numerous mitochondria, which are typical of pheromone gland cells in other insects.

COMPONENTS OF THE SEX PHEROMONE GLAND OF THE EASTERN SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

The major component of the sex pheromone of the eastern spruce budwonn was established by Weatherston et al. (1971) to be trans-11-tetradecenal. Subsequently it was found (Sanders and Weatherston 1976) that a small proportion of cis-11-tetradecenal was essential to attraction and indeed was a component of the natural pheromone. In addition Weatherston and Maclean (1974) have shown that the female sex pheromone gland contains trans-11-tetradecenol, a presumed biosynthetic precursor to the aldehyde.

Isolation, identification, and synthesis of a female sex pheromone of the navel orangeworm,Amyelois transitella (Lepidoptera: Pyralidae)

A sex pheromone of the navel orangeworm,Amyelois transitella (Walker), was obtained from ether rinses of the sex pheromone gland of calling females. The pheromone was isolated by means of liquid and gas chromatography and was identified as one of four possible geometrical isomers of 11,13-hexadecadienal by means of spectroscopic and microchemical methods. Synthesis and laboratory bioassay of all four isomers revealed that only the (Z,Z) isomer was biologically active. (Z,Z)-11,13-hexadecadienal elicited quantitatively similar activation and attraction responses byA. transitella males as did the natural product.

Laboratory evaluation of the sex pheromone and mating inhibitor of the red bollworm Diparopsis castanea Hampson (Lepidoptera, Noctuidae)

AbstractThe four components of the synthesised sex pheromone of Diparopsis castanea Hmps. are dodecan-1-yl acetate (I); trans-9-dodecen-1-yl acetate (IIA); 11-dodecen-l-yl acetate (IIB); and trans-9,ll-dodecadien-l-yl acetate (IV). Increasing the proportion of IIA in a I/IIA/IIB/IV mixture progressively decreased male excitation in a laboratory bioassay, whilst in the absence of I all concentrations of IIA tested were equally inhibitory. The synthetic combination of 80% IV (93% trans: 7% cis) and 20% IIB (=dicastalure), was 485 times more potent in eliciting male activity than a female sex pheromone gland extract. Reduction in male response to crude extract occurred through exposure of males to glandular IIA and through reduced pheromone volatility caused by extracted triglycerides. Maximum quantities of pheromone were detected in the female sex pheromone gland 6–12 h into scotophase and for at least 30 min into photophase. Significantly greater bioassay responses were elicited by the optimal field combination of 80% IV and 20% IIB than for other ratios tested. Excitation and clasper extension were observed in response to the non-attractive IIB moiety and this indicates a role in close-range mating behaviour for this component. The threshold level of male response was estimated to occur in response to sex pheromone at an aerial concentration of 9·2 molecules IV mm3/s−1. This suggests that aerial concentrations of 102–103 times the male threshold response level may be sufficient to cause successful communication disruption in the field. The problems of relating the non-oriented responses in an assay of this type to directional responses in traps are briefly discussed.

Female sex pheromone release and the timing of male flight in the red bollworm Diparopsis castanea Hmps. (Lepidoptera, Noctuidae), measured by pheromone traps

AbstractThe female sex pheromone gland of Diparopsis castanea Hmps. consists of modified intersegmental tissue between the eighth and ninth abdominal segments. Glands contain an average of 12·73 ×10–3 μg of pheromone consisting of 80·4±2·0% trans-9, 11-dodecadien-l-yl acetate (range 72·7–86·7%) and 19·6±2·0% 11-dodecen-l-yl acetate (range 13·3–27·3%). Although no significant correlation exists between female body weight and pheromone content of the gland, the duration of sex pheromone release over the lifespan of a female is positively correlated with its weight on emergence. Six behavioural steps may be recognised in the precopulatory behaviour of females but the frequency and duration of sex pheromone release is strongly influenced by both temperature and light intensity. At 25°C females typically ‘call’ on two or more occasions for 41–50% of the night, calling commencing earlier at cool (13·4°C) temperatures than at moderate (19·4°C) or warm (25·0°C) temperatures. Calling by mated females increases considerably from four to five nights after mating but is typically of shorter duration than for virgins. The dispersal flight of Diparopsis males in cotton crops commences almost immediately after sunset and before the end of dusk, with peak male catches in sex pheromone traps occurring earlier in the cooler months of May and June (20.00–22.00 h) than in November (02.00–04.00 h). The Diparopsis synthetic sex pheromone, dicastalure, traps a greater proportion of males and females both earlier and later in the night than virgin females and this ‘timing advantage’ may be important in a pheromone control programme based on disruption of communication between the sexes.

Natural Inhibitor of the Gypsy Moth Sex Attractant

INHIBITION or masking of sex pheromone response by natural products occurring in the pheromone producing gland has been described in the gypsy moth1, Porihetria dispar (L.), other Lepidoptera2,3 and insects in additional orders4,5 but none of the inhibitors has been identified. We report here that an olefin, 2-methyl-cis-7-octadecene, present6 in the female sex pheromone gland of the gypsy moth, inhibits male attraction to the female sex attractant pheromone, which was identified as cis-7,8-epoxy-2-methyloctadecane6.

Bioassay, Morphology, and Histology of the Female Sex Pheromone Gland of Dioryctria abietella (Lepidoptera: Pyralidae (Phycitinae))1

The female sex pheromone gland of Dioryctria abietella (Denis & Schiffermuller) is located in the intersegmental membrane between abdominal segments 8 and 9. The gross morphology and histology of the gland are described. The function of the gland was confirmed by bioassay with male moths, and responses were different for relatively high and low concentrations of the sex pheromone. Results of the bioassays indicated that the mating behavior of the male was influenced by other stimuli in combination with the sex pheromone.

Glandes Exocrines Males et Femelles Intervenant dans le Comportement de Pariade d'Acrolepia Assectella [Lepidoptère: Plutellidae

SummaryE. Thibout: Male and female sex pheromone glands involved in the courtship behaviour of the leek moth, Acrolepia assectella (Lepidoptera).The histological and morphological studies of the female sex pheromone gland and of the male odoriferous organs are made. The female gland is situated in the intersegmental membrane between the 8th and 9th abdominal segment. The secretory cells of the male scentpencil glands are epithelial cells situated at the base of one of the two kinds of scales.

The Female Sex Pheromone Gland of the Pink Bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae)1

The female sex pheromone gland of the gelechiid moth Phthorimaea operculella (Zeller), the potato tuberworm, is an eversible sac situated dorsally in the intersegmental membrane between the 8th and 9th abdominal segments (Adeeson et al. 1969). The presence of a female sex pheromone in Pectinophora gossypiella (Saunders) was reported by Flaschentrager et al. (1957); and the source of the pheromone was shown to be in the terminal segments of the abdomen (Berger et al. 1964). When pressure is applied to the abdomen of a female pink bollworm moth, a sac-like structure is everted which is similar in location to the pheromone gland of the potato tuberworm moth.

Permanent Whole-Mount Preparation of Lepidopterous Genitalia for Complete Visibility of the Female Sex Pheromone Gland1

The sex pheromone gland of female Lepidoptera is typically situated in the abdomen close to the genital openings (Jefferson et al. 1966). As this gland originates from hypodermal cells in the intersegmental fold, generally between the 8th and 9th abdominal segments (G&tz 1951), it is hidden from view when the genitalia are in their normal retracted position. Thus, one often finds difficulty in detecting its presence and even more so in observing its exact structure. However, by applying the Feulgen reaction for deoxyribonucleic acid (DNA) to whole genitalia preserved in an extruded position, it is possible to discern the size, shape, and overall structure of this gland in permanent whole-mount preparations. As only nuclei are deeply stained by this procedure, the extensive accumulation of modified hypodermal cells―relatively large columnar cells with large round-to-oval, magenta-staining nuclei―in the intersegmental fold between the 8th and 9th abdominal segments indicate the presence of this female sexual scent organ, the true identity of which can be proven by bioassay (Roelofs and Feng 1967). The method described here for obtaining permanent whole-mount preparations of the female sex pheromone gland was devised to simplify comparative studies on the structure of this organ in adult tortricids (Bronskill et al. in press).

Sex Pheromones of Noctuid Moths.1 XVI. The Morphology of the Female Sex Pheromone Glands of Eight Species2

In Autographa californica (Speyer), Pseudoplusia includens (Walker), and Rachiplusia ou (Guenee) (Plusiinae) the female sex pheromone gland is situated dorsally in the intersegmental membrane between the 8th and 9th abdominal segments. The gland of P. includens is an eversible sac, but in A. californica and R. ou it may be either an eversible sac or an eversible fold. In Spodoptera exigua (Hubner) and Feltia subterranea (F.) (Amphipyrinae) the gland is an eversible sac situated ventrally in the intersegmental membrane between the 8th and 9th abdominal segments. The gland in Heliothis phloxiphaga Grote & Robinson, H. virescens (F.), and H. zea (Boddie) (Heliothinae) is a complete ring of glandular epithelium between the 8th and 9th abdominal segments, but in H. virescens the gland is more strongly developed ventrally. The glands of these 8 species are described and compared with the glands of Trichoplusia ni (Hubner) and Prodenia ornithogalli Guenee. Evidence of function of the glands is presented for Pseudoplusia includens, Prodenia ornithogalli, and H. virescens.

Sex Pheromones of Noctuid Moths. XI. The Ultrastructure of the Apical Region of Cells of the Female Sex Pheromone Gland of Trichoplusia ni12

Histological studies of the pheromone gland of Trichoplusia ni (Hubner) by Jefferson et al. (1966) revealed a vacuole-laden cytoplasm characteristic of secretory cells. The apical region of the cell consisted of vertical striations, the detail of which could not be determined with the light microscope. However, the structures were considered either fibers or folds of the cell membrane as found by Steinbrecht and Schneider (1964) in the pheromone gland of Bombyx mori L.