Source Of Sex Pheromone Research Articles

The odour makes the difference: male moths attracted by sex pheromones ignore the threat by predatory bats

How animals adjust their foraging or mate finding behaviour according to the risk of predation has received much attention recently. However, few studies have focused on the behaviour of prey when stimuli representing different adaptive behaviours originate from different sensory modalities. Here we present data on how male moths trade off odour‐mediated mate attraction and auditory‐mediated predator avoidance depending on the relative quality of the mate signal. Males of Agrotis segetum (Noctuidae) and Plodia interpunctella (Pyralidae), orienting towards a sex pheromone source in a flight tunnel, were exposed to ultrasound mimicking the echolocation calls of a bat, i.e. high predation risk. Males of both species accepted the predation risk when attracted to pheromone sources of high quality (female gland extract or complete synthetic blend at high dose), manifested in similar percentages reaching the pheromone source in moths with and without ultrasound exposure. In contrast, a lower proportion of ultrasound‐exposed males than unexposed ones located the pheromone source when moths were flying towards pheromone sources of low quality (incomplete synthetic blend or complete synthetic blend at low dose), due to more time invested in defence manoeuvres. Furthermore, the risk taking behaviours of these moth species seem to be similar in spite of the fact that their ultrasonic hearing systems have evolved independently.

Increased Parasitization of Aphids on Trap Plants Alongside Vials Releasing Synthetic Aphid Sex Pheromone and Effective Range of the Pheromone

Aphid-infested cereal trap plants were used to detect the effects of aphid sex pheromone components on aphid parasitoid activity in arable field margins. The presence of aphid sex pheromones significantly increased parasitization levels by aphid parasitoids on the plants. By placing plants alongside and at varying distances away from a pheromone-releasing vial, the technique was used to measure the distance over which a point source of aphid sex pheromone could increase parasitization levels. Pheromone-releasing vials significantly increased parasitization by the generalist parasitoid Praon volucre on plants adjacent to vials and on plants placed 20 cm away. When the distance between pheromone-releasing vials and aphid-infested plants was increased to 1 m, parasitization by P. volucre was increased only on the plant adjacent to the vial, whereas parasitization by the specialist parasitoid Aphidius rhopalosiphi was also increased on plants placed 1 m away. This indicates a possible difference between the parasitoids in their foraging behaviour in response to semiochemical cues during host selection. When the experiment was repeated with some trap plants placed 3 m away from the pheromone-releasing vial, parasitization was again concentrated on plants directly alongside the vial, but only P. volucre appeared to be active in the field at the time of this experiment, so the effect on A. rhopalosiphi could not be assessed. The results are encouraging for the prospects of using aphid sex pheromones to manipulate parasitoids in order to improve aphid population control.

Coordination of flipflopping neural signals and head turning during pheromone-mediated walking in a male silkworm moth Bombyx mori

Male silkworm moths, Bombyx mori, move their heads side-to-side during zigzag walking toward a source of sex pheromone. High-speed video analysis revealed that changes in walking direction were synchronized with this head turning. Thus the direction of the walking is indicated by the direction of the head turning. Head turning was regulated by neck motor neurons which innervate the cervical ventral muscles and the ventral muscles through the second cervical nerve. To determine the role of the `flipflop' state transition in spike activity carried by descending interneurons from the brain to the thoracic ganglion, we recorded pheromonal responses simultaneously from flipflop descending interneurons and a single cervical ventral 1 neck motor neuron. The activity of the cervical ventral 1 neck motor neuron was synchronized to that of the flipflop descending interneurons. The cervical ventral 1 neck motor neuron was morphologically identified using confocal imaging. Our results demonstrate that the flipflop signals play an important role in instructing turning signals during the pheromone-mediated behavior in a male B. mori.

Evidence for the Site of Female Sex Pheromone Production in Periplaneta americana

We used bioassays to determine the sex pheromone production site in the female American cockroach (Periplaneta americana). Bioassayed extracts from various body parts aroused sexual responses from unmated males. However, the extract of hindgut (including both colon and rectum) induced strong responses. Colon extract stimulated the strongest sexual response. To compare the sex pheromone contents of atrial glands, pygidium, rectum, and colon, we recorded the EAG responses of male antennae to these extracts. Among the four tissues, colon extract caused the strongest EAG response. From gas chromatographic (GC) analysis, the quantities of periplanone-A (PA) and periplanone-B (PB) (the main sex pheromone components in female American cockroach) were 0.34 and 8.31 ng, respectively, in the colon of a virgin female. The ratio of PA to PB was ca. 1:24. The present results are different from those reported in a previous study, in which it was concluded that atrial glands are the sites of sex pheromone production in P. americana, and from GC analysis the quantity of PB was estimated to be 60 ng/female. There was no difference in sexual behaviors induced by colon and atrial glands of calling virgin females. It is unclear whether the colon is the sole sex pheromone source in the female American cockroach.

Sites of release of Putative Sex Pheromone and Sexual Behaviour in FemaleCarcinus maenas(Crustacea: Decapoda)

Pre-moult femaleCarcinus maenasurine was confirmed as a source of putative sex pheromone. The sexual and temporal specificity of bioactivity in pre-moult female urine was demonstrated when urine samples taken from inter-moult and pre-moult male crabs, and inter-moult females, failed to generate a sexual response from receptive males. Detection sensitivity of male crabs to pre-moult female urine was established at a dilution factor of 1μl of urine in 10ml of seawater. Experimental blockage of the site of urine release (the antennal gland opercula) failed to diminish the chemical attractiveness of pre-moult female crabs to test males, implicating at least one further site of putative pheromone release. Observations of female sexual behaviour demonstrated an active role by pre-moult and post-moult female crabs when introduced to male crabs whose locomotor movement had been temporarily restricted.

Behaviour of flying oriental fruit moth males during approach to sex pheromone sources

Abstract. The pheromone‐modulated upwind flight tracks of Grapholita molesta (Busck) males were video recorded as they approached a point‐source of pheromone in a wind tunnel. The field of view of the video recording was divided longitudinally into 33 cm sections and the flight behaviour of the males in these sections was measured and compared as they approached from 233 cm to 50 cm downwind of the pheromone source. As the males approached the source, their mean ground speeds decreased. The mean values of their track angles increased with respect to due upwind (0d̀), indicating movement more across the wind. These changes resulted mainly from the males decreasing their air speeds as they progressed up the plume toward the source. They did not change the average direction of their steering (course angle). Thus, the increase in track angles resulted from the males allowing themselves to drift more in the wind as they approached the odour source. The males also increased their average rate of counterturning as they approached the source. The net result of all these behavioural changes was a track that slowed and grew narrower, giving the impression that the males were ‘homing‐in’ on the pheromone source as they approached. Causes of these systematic changes in behaviour are considered with respect to the known systematic changes in pheromone plume structure as the distance to the source decreases.

Pheromone-mediated responses of male cabbage looper moths,Trichoplusia ni, following various exposures to sex pheromone or (Z)-7-dodecenol

Prolonged preexposure (three days) of maleTrichoplusia ni to its six-component sex pheromone blend or its major pheromone component, (Z)-7-dodecenyl acetate, reduced subsequent upwind flight responses to a pheromone source. Preexposure to (Z)-7-dodecenol increased upwind flight responses to a pheromone source combined with (Z)-7-dodecenol. The impact of long-term preexposures was moderate when compared to the more immediate effects of background noise. When (Z)-7-dodecenyl acetate was presented as background noise, all maleT. ni failed to respond to a plume of the full pheromone blend. However, most moths succeeded in locking on to the pheromone plume and contacting the pheromone source in the presence of the five minor pheromone components as background noise. When (Z)-7-dodecenol was released as background noise the response rate to a pheromone source containing (Z)-7-dodecenol was increased dramatically. This indicates that males became adapted to (Z)-7-dodecenol while responding to the pheromone source. The results of this study indicate that both long-term preexposure treatments and immediate exposure to background noise can limit the ability of maleT. ni to respond to sex pheromone sources.

Interactions between male moths of the lightbrown apple moth, Epiphyas postvittana (Walker) (Lep.: Tort.), landing on synthetic sex pheromone sources in a wind‐tunnel

Abstract. This study was designed to determine whether landings of males of Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae) on synthetic sex pheromone sources are influenced by other males which have preceded them in flying to and landing on the sources. The investigation comprised two separate experiments. In one, using a single pheromone source, insects released singly were compared with insects released in groups of three, and in the other, insects released in groups of five were presented with a choice between two identical sources. The resolution for changes in attractancy was higher in the choice experiment which demonstrated an increase in attraction for a source on which males had already landed and remained whilst the new male flew towards it. A single resident insect increased the source attractancy by a factor of 1.40 and a pair of insects by 1.77 compared with an empty source. With the single sources the data exhibited the same trend but the result was rendered not significant by an insufficient amount of data, although approximately equal times were allocated to each experiment. To achieve a significant result with the single sources at least 6 times as much data would need to be collected.

Effects of moth size on velocity and steering during upwind flight toward a sex pheromone source byLymantria dispar (Lepidoptera: Lymantriidae)

Free-flying male gypsy moths (Lymantria dispar)head upwind in response to sex pheromone. Males typically fly in a zigzag path, with mean ground speeds modulated by pheromone concentration and ambient temperature, but not by wind speed. We studied the effect of male size on ground speeds and additional flight track parameters. Mean net ground speed along the wind line was fastest among large males and was slower in medium and small males. Similarly, mean airspeeds and ground speeds along the flight tracks increased from small to large males. Males from all three size classes steered similar mean course angles. Small males, however, had larger mean track angles than larger males, and mean drift angles were also larger for small males. Turning rates (frequency of turns across the wind line) and interturn distances (net crosswind displacement between turn apices) were not significantly different among the three size classes; however, large males had a trend toward a reduced mean turning rate and increased mean interturn distance. The steering of similar course angles by males from all three size classes and the higher airspeeds among larger males (the two variables males can actively control during free flight) suggest that changes in other flight parameters are a result primarily of increased ground speed among large males.

Attraction and learning in mate-finding by solitary bees, Lasioglossum (Dialictus) figueresi Wcislo and Nomia triangulifera Vachal (Hymenoptera : Halictidae)

Males of the solitary sweat bee, Nomia triangulifera, patrol over large areas where thousands of females emerge, searching for receptive females. The daily operational sex ratio is strongly male-biased. Males contact dead, frozen (untreated) females more frequently than they contact females which were washed in hexane, showing that olfactory cues are utilized in mate-finding. A major source of female sex pheromone is in the head. Male pouncing on females is temporally non-random, indicative of group stimulation. Bioassays show that newly emerged females are more attractive to males than are older pollen-collecting females. Female odors are individually distinctive, based on male responses, and there is much variation among females in their attractive properties. Male responses to female odors suggest that learning is important for mating in natural populations. In contrast, the following hypotheses are unlikely to account for the observed behavior: (1) dissipation of female odors; (2) site learning and avoidance behavior by males; (3) decay of male motivation; or (4) male-produced repellents effective against other males. Laboratory and field studies show that female Lasioglossum figueresi produce individually-distinctive odors, which are attractive to males. There is considerable inter-individual variation among females in their attractiveness to males among sexually immature females. Male responses to female odors decay over the course of the presentation, suggesting the importance of learning in natural populations, although several alternatives could not be tested.

Direct Measurement of the Flight Behavior of Male Moths to Calling Females and Synthetic Sex Pheromones

Abstract The approach of male Lobesia botrana (Lepidoptera: Tortricidae) in the wind tunnel to a source of sex pheromone was studied using two video cameras connected to image processing equipment. Three-dimensional records demonstrate that the flight to calling females is quite direct compared to the zigzag flight reported for other species. Convoluted paths displaying bimodal distribution of track and course angles were only obtained with a synthetic pheromone blend consisting of E-7,Z-9-dodecadienyl acetate, E-7,Z-9-dodecadien-l-ol and Z-9- dodecenyl acetate at the proportions of 1 /0.2/0.05. This suggests that this blend is still suboptimal and that zigzag flight may be due to a lack of precision in upwind motion caused by inadequate composition of the stimulus

Codling Moth: Male Moth Activity in Response to Pheromone Lures and Pheromone-Baited Traps at Different Elevations Within and Between Trees

To characterize the behavior of codling moth, Cydia pomonella (L.), males to sex pheromone sources, we determined the lapsed time for response, number responding, and number of attempted pseudocopulations directed to pheromone placed at various heights in or near apple trees. The time for and number of responses was similar at any height as long as the pheromone source was within and not outside the tree's canopy. Responses to pheromone and captures of moths were significantly lower for pheromone sources or traps outside the tree canopy, whether above, below or between trees. The maximum numerical response was at the 3.0-m level, 1.0–1.5 m from the top of the tree. In an unsprayed apple orchard, the number of moths caught in traps at 3.5 m was not significantly different from the number caught at 1.5 m, but in a sprayed orchard, the number caught at 3.5 m was significantly higher than at 1.5 m in six of 10 biweekly comparisons. Efficiency of low traps (1.5 m) relative to high traps depended on the position of the low trap in relation to the canopy. The canopy effect was larger than the height effect.

Pheromone Trap for Monitoring Insecticide Resistance in the Pink Bollworm Moth (Lepidoptera: Gelechiidae): New Tool for Resistance Management

A rapid technique using sex pheromone and insecticide-laced traps was developed for measuring insecticide resistance in pink bollworm moth, Pectinophora gossypiella (Saunders). This method was developed in the laboratory by allowing males to fly upwind to a sex-pheromone source in a wind tunnel, and then trapping them on sticky cards (laced with various doses of pyrethroid insecticides) inserted into standard delta traps. Using this technique, populations of adult male P. gossypiella trapped in the field were shown to be more resistant to permethrin and fenvalerate in fields frequently treated with pyrethroids than in fields with little or no exposure to these insecticides. The new method eliminates handling of insects that is involved in other methods of assessing toxicity, and is compatible with the current practice of monitoring populations with pheromone traps. It was important to test and standardize duration of males' postcapture exposure to insecticide-laced sticker, temperature that males were exposed to after capture, quantity of sticker used, and age of males when captured.

Role of insect sex pheromones in mating behavior. V. Profile of process on male flying approach toward sex pheromone source

Application of the kinetic theory of gas molecules to male zigzagging orientation, which is assumed as repeated encounter between sex pheromone puff and a flying male moth, derived a linear relationship between the number of turnings and the distance from the source where male began repeated turnings. Similar results are also obtained by computer simulation. This relationship was already obtained inHyphantria cunea males in the field within 2.0 meters downwind from the source. Theoretical simulation and observation results led us to conclude that male repeated turnings are restricted by the time during which males are able to take the approaching behavior to the source.

Sex pheromone source location by garter snakes:

Male plains garter snakes,Thamnophis radix, tested in a 240-cm-long arena can detect directional information from a female pheromone trail only when the female is allowed to push against pegs while laying the trail. The female's normal locomotor activity apparently deposits pheromone on the anterolateral surfaces of vertical structures in her environment. The male sensorily assays the sides of these objects and from this information determines the female's direction of travel.

Finding of a sex pheromone source by gypsy moths released in the field

“Moths display some of the most striking examples of long-distance chemical communication in the animal kingdom”1. Recent theories of how the male moths find a distant female have invoked steering by two different directional cues: (1) gradients of odour concentration in the air, used in ‘aerial odour-trail following’, and (2) the wind, used in ‘odour-modulated anemotaxis’2–7. Laboratory evidence has favoured the latter theory as well as contradicting the earlier radiation theories8–11, but the issue could not be settled without recording in the field the flight track of a male moth and, simultaneously, the track of the odour plume. This has now been done with gypsy moths and wind-borne bubbles, confirming theory (2) and showing in addition that cross-wind casting itself contributes to a moth's progressive approach to the odour source, an unexpected consequence of the way odours are dispersed by the wind12.

The analysis of flight paths of male Egyptian cotton leafworm moths, Spodoptera littoralis, to a sex pheromone source in the field

ABSTRACT. The flight of male Spodoptera littoralis (Boisd.) (Noctuidae) towards a pheromone source was recorded during the early part of the night using a cine camera and an image intensifier. The cine films were analysed frame by frame to produce flight tracks from which it was possible to calculate the mean advance rate of moths towards the pheromone source and their projected ground speed, for a series of positions downwind of the source. As wind speed was measured the moth's air speed was also estimated. The moths compensated for changes in wind speed by varying their air speed, hence maintaining a ground speed independent of wind speed. The ground speed itself was found to decrease as moths flew closer to the pheromone source.

Water in Desert Ecosystems. US/IBP Synthesis Series, Volume 11. Daniel D. Evans , John L. Thames

Previous articleNext article No AccessNew Biological BooksWater in Desert Ecosystems. US/IBP Synthesis Series, Volume 11. Daniel D. Evans , John L. Thames Boyd R. StrainBoyd R. Strain Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 57, Number 2Jun., 1982 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/412764 Citations: 16Citations are reported from Crossref Copyright 1982 Stony Brook Foundation, Inc.PDF download Crossref reports the following articles citing this article:A. G. Carton, J. C. Montgomery Evidence of a rheotactic component in the odour search behaviour of freshwater eels, Journal of Fish Biology 62, no.33 (Mar 2003): 501–516.https://doi.org/10.1046/j.1095-8649.2003.00015.xPatricia Lextrait, Jean -Claude Biemont, Jean Pouzat Comparison of walking locomotory reactions of two forms ofCallosobruchus maculatus males subjected to female sex pheromone stimulation (Coleoptera: Bruchidae), Journal of Chemical Ecology 20, no.1111 (Nov 1994): 2917–2930.https://doi.org/10.1007/BF02098398Paul Harrewijn, Albert K. Minks, Chris Mollema Evolution of plant volatile production in insect-plant relationships, Chemoecology 5-6, no.22 (Jun 1994): 55–73.https://doi.org/10.1007/BF01259434Paul A. Moore, Marc J. Weissburg, J. Michael Parrish, Richard K. Zimmer-Faust, Greg A. Gerhardt Spatial distribution of odors in simulated benthic boundary layer flows, Journal of Chemical Ecology 20, no.22 (Feb 1994): 255–279.https://doi.org/10.1007/BF02064435Steven C. Peterson, T. D. Fitzgerald Chemoorientation of eastern tent caterpillars to trail pheromone, 5?-Cholestane-3,24-dione, Journal of Chemical Ecology 17, no.1010 (Oct 1991): 1963–1972.https://doi.org/10.1007/BF00992581Paul A. Moore, Nat Scholz, Jelle Atema Chemical orientation of lobsters, homarus americanus, in turbulent odor plumes, Journal of Chemical Ecology 17, no.77 (Jul 1991): 1293–1307.https://doi.org/10.1007/BF00983763William G. Eberhard Imprecision in the behavior ofLeptomorphus sp. (Diptera, Mycetophilidae) and the evolutionary origin of new behavior patterns, Journal of Insect Behavior 3, no.33 (May 1990): 327–357.https://doi.org/10.1007/BF01052113R. Patrick Akers, David L. Wood Olfactory orientation responses by walking femaleIps paraconfusus bark beetles, Journal of Chemical Ecology 15, no.44 (Apr 1989): 1147–1159.https://doi.org/10.1007/BF01014818R. Patrick Akers, David L. Wood Olfactory orientation responses by walking femaleIps paraconfusus bark beetles I. Chemotaxis assay, Journal of Chemical Ecology 15, no.11 (Jan 1989): 3–24.https://doi.org/10.1007/BF02027770R. Patrick Akers Counterturns initiated by decrease in rate of increase of concentration, Journal of Chemical Ecology 15, no.11 (Jan 1989): 183–208.https://doi.org/10.1007/BF02027782Simone Yetman, Gerald S. Pollack Proboscis extension in the blowfly: directional responses to stimulation of identified chemosensitive hairs, Journal of Comparative Physiology A 160, no.33 (Jan 1987): 367–374.https://doi.org/10.1007/BF00613026E. Zaborski, P. E. A. Teal, J. E. Laing Kairomone-mediated host finding by spruce budworm egg parasite,Trichogramma minutum, Journal of Chemical Ecology 13, no.11 (Jan 1987): 113–122.https://doi.org/10.1007/BF01020355Yoshitoshi Hirooka Role of insect sex pheromones in mating behavior. V. Profile of process on male flying approach toward sex pheromone source, Journal of Ethology 4, no.11 (Jun 1986): 27–37.https://doi.org/10.1007/BF02348250H. Distel, R. Hudson The contribution of the olfactory and tactile modalities to the nipple-search behaviour of newborn rabbits, Journal of Comparative Physiology A 157, no.55 (Sep 1985): 599–605.https://doi.org/10.1007/BF01351354M. W. Sabelis, P. Schippers Variable wind directions and anemotactic strategies of searching for an odour plume, Oecologia 63, no.22 (Jan 1984): 225–228.https://doi.org/10.1007/BF00379881ROGER P. CROLL GASTROPOD CHEMORECEPTION, Biological Reviews 58, no.22 (May 1983): 293–319.https://doi.org/10.1111/j.1469-185X.1983.tb00391.x

Sex pheromone-induced chemolocation in the male American cockroach,Periplaneta americana

Males of the American cockroach,Periplaneta americana, have evolved an efficient search strategy enabling them to locate a source of sex pheromone in the absence of directional information derived from wind. Since these animals are able to utilize chemotaxis to orient almost directly to the source from 45-50 cm away, it is only necessary that they maximize their chances of getting within that range once they perceive the pheromone. They accomplish this by: (1) increasing their overall levels of activity and (2) initiating local search. In this way, they are able to cover a rather large area in a short period of time, i.e., before the source female changes location. If their paths take them to within 45 cm of the source, they are able to locate it soon thereafter. It is probable that very similar strategies are utilized by many other nonflying insects to locate sources of airborne odors.

Pheromone Orientation: Role of Internal Control Mechanisms

Male American cockroaches walk a zigzag path upwind toward a source of female sex pheromone. Although the maximum width of the pathway is regulated by the width of an odor plume, many turns are made before the edge of a wide plume is encountered. In addition to the pheromone regulation of the insect's orientation movements, an internal mechanism appears to influence the zigzag turning pattern.