Behavior and pheromone studies withAttagenus elongatulus Casey (Coleoptera: Dermestidae)

Males ofAttagenus elongatulus Casey responded to a source of female odor with a characteristic sequence of actions which included: extension of the antennae, elevation of the body by leg extension, rapid zig-zag running, and intermittent bobbing up and down. The courtship sequence also consisted of several activities and was usually followed by a typical copulatory act of less than 1-minute duration. Virgin females exhibited calling behavior which was associated with pheromone release. Female calling activity, female pheromone content, and male responsiveness followed a diurnal cycle with peak values occurring during the earlier hours of the 16L8D photoperiod. Quantitative bioassay indicated that a 50% male response level (RD₅₀) occurred at ca. 0.014 female equivalent (FE) exposure.     

Isolation and identification of a major sex-attracting component ofAttagenus elongatulus (Casey) (Coleoptera: Dermestidae)

A major sex-attracting component in extracts of virgin females ofAttagenus elongatulus Casey was isolated by various chromatographic techniques. The chemical was identified as (Z,Z)-3,5-tetradecadienoic acid by spectroscopic analyses.     

Chemical basis for interspecific responses to sex pheromones ofTrogoderma species (Coleoptera: Dermestidae)

Interspecific responses among severalTrogoderma species have been correlated with their pheromone components. The most important component emitted by four of the species is (Z)- or (E)-14-methyl-8-hexadecenal, which is not detectable in extracts of macerated beetles. The response to macerated beetles is probably due to the corresponding alcohol and ester. The recency of common origin of seven species is discussed.     

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.Mention of a proprietary product does not constitute an endorsement by the Minnesota Agricultural Experiment Station.     

Sex pheromone communication in the odd beetle,Thylodrias contractes motschulsky (Coleoptera: Dermestidae)

Adult virgin females of the odd beetle,Thylodrias contractus, produce a volatile sex pheromone that influences the behavior of conspecific males and attracts them in laboratory olfactometer tests. The active substance can be collected by allowing virgin females to walk on absorbent paper disks. Disks exposed to mated females do not elicit a response from males. The male odd beetle repeatedly rubs the antennae, head, and thorax of a female with a setate glandular area on his second abdominal sternum during courtship, probably secreting a reciprocally active aphrodisiac substance.Journal Paper No. J-10248 of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA 50011. Project No. 2259.     

Chemical communication in the mating behavior ofTrogoderma glabrum (Herbst) (Coleoptera: Dermestidae)

Male mating behavior of the stored product pest beetleTrogoderma glabrum (Herbst) was analyzed into three major phases: arousal/searching, preliminary recognition, and genital (copulatory). Airborne pheromone released by calling females elicits male arousal via antennal sensillae. Contact chemoreception via male mouthpart sensillae appears to be necessary for copulation to occur. A procedure was developed for quantitative bioassay of presumptive pheromone compounds in both airborne and contact chemoreception. (E)-14-methyl-8-hexadecenal, present in airborne pheromone, but not detectable in extracts of whole females, elicits both arousal and attempted copulation. The activity of (E)-14-methyl-8-hexadecenal is equal to that of the total airborne pheromone. Activity of additional possible pheromone component candidates [including (E)-14-methyl-8-hexadecen-1-ol, -caprolactone,n-hexanoic acid, and methyl (Z)-7-hexadecenoate] was investigated. Evidence for a behavioral role forn-hexanoic acid is presented.     

Sex pheromone components and calling behavior of the female dermestid beetle,Trogoderma variabile Ballion (Coleoptera: Dermestidae)

Females of the dermestid beetle,Trogoderma variabile Ballion, exhibit a diel pattern of calling behavior. A potent sexual excitant and attractant for the male beetles can be collected on Porapak Q during aeration of female beetles, but cannot be detected in extracts of macerated females. The attractant has been identified as (Z)-14-methyl-8-hexadecenal. Of the five additional compounds previously identified as attractants in otherTrogoderma species, only two were found; (Z)-14-methyl-8-hexadecen-1-ol is present in extracts of macerated female beetles, but not in extracts of Porapak Q, and -caprolactone is present in extracts of Porapak Q. Three collection procedures were necessary to ensure that all the pheromone components had been isolated. Synthetic (Z)-14-methyl-8-hexadecenal elicits attraction and sexual arousal inT. Variabile males.Mention of a commercial or proprietary product in this paper does not constitute an endorsement of that product by the USDA.     

Identification of the sex pheromone of the guernsey carpet beetle,Anthrenus sarnicus Mroczkowski (Coleoptera: Dermestidae)

It has been confirmed that adult virgin females ofAnthrenus sarnicus Mroczkowski exhibit a characteristic headstand posture that is associated with the release of a sex pheromone. Volatiles trapped on filter papers suspended above calling females were attractive to adult virgin males when tested in a two-choice target bioassay. Separate aeration extracts of males and females were analyzed by gas chromatography-mass spectrometry and showed that decanol and decyln-butyrate were released by females only. These components were present in approximately equal amounts and accounted for about 90% of the total area of the chromatogram. Decyl butyrate produced an electroantennogram response with a larger response from males than females. Behaviorally, a mixture of 10g of decanol and 10g of decyl butyrate attracted 88% of males and 10g of decyl butyrate alone attracted 82% of males in the bioassay. The role of decyl butyrate as a sex pheromone is convincing, but this is not the case for decanol.     

Olfactory behavior and receptor potentials of the khapra beetleTrogoderma granarium (Coleoptera: Dermestidae) induced by the major components of its sex pheromone,certain analogues,and fatty acid esters

On the basis of the antennal receptor potentials and the extent of attraction and copulation induced in unmated male khapra beetles, (Z)- and (E)-14-methyl-8-hexadecenal were recognized as the most important components of the pheromone system of femaleTrogoderma granarium (Everts), and were named (Z)- and (E)-trogodermal. Air blown over 10^–5 to 10^–4 g of (Z)-trogodermal produced receptor potentials equivalent to that elicited by one virgin femaleT.granarium, while 10^–2 g of (Z)-trogodermal was required to cause complete attraction and copulation of unmated males. (Z)-Trogodermal was about 10 times more active than (E)-trogodermal. (Z)-8-Hexadecenal was 10^–2 times less effective than (Z)-trogodermal in causing attraction and 10⁴ time less active in stimulating copulation. (Z)- and (E)-14-methyl-8-hexadecen-1-ol and methyl (Z)- and (E)-14-methyl-8-hexadecenoate displayed a relatively low activity for unmated male khapra beetles. Methyl and ethyl oleate, ethyl linoleate, ethyl palmitate, and ethyl stearate were less effective than (Z)-trogodermal by 6–8 orders of magnitude and are nonspecific attractants. The intensity of response to a particular compound was consistent when assessed by the essential components of mating behavior: receptor potentials, attraction, and copulation.     

Stereospecific synthesis of (Z,Z)-3,5-tetradecadienoic acid,a component ofAttagenus elongatulus (Casey) pheromone

A simple stereospecific synthesis of (Z,Z)-3,5-tetradecadienoic acid is described based upon coupling of 1-decyne and 3-butyn-1-ol to give 3,5-tetradecadiyn-1-ol. Subsequent reduction of the diyne to (Z,Z)-3,5-tetradecadien-1-ol and oxidation of the dienol gave the desired acid.Attagenus elongatulus were strongly attracted to the pure acid.     

Determination of distribution of harmful click beetle species (Coleoptera,Elateridae) by synthetic sex pheromones

By means of pheromone traps containing synthetic sex pheromones, areas of the most harmful click beetle species,Agriotes obscurus,A. lineatus, A. sputator, A. gurgistanus, A. ustulatus, A. tauricus Heyd, andA. lineatus, occurring in southern regions and differing biologically from the so-called northern species, have been specified and charted in the European and central Siberian areas of the former USSR.     

Male response to natural sex pheromone ofMigdolus fryanus westwood (Coleoptera: Cerambycidae) females as affected by daily climatic factors

Males of the sugarcane borer,Migdolus fryanus (Coleoptera: Cerambycidae), are attracted to females by means of a sex pheromone. Mating usually occurs during a few days from October to March under field conditions in São Paulo State, Brazil. This work reports on mating of this species as affected by daily climatic factors, during a single nuptial flight. Maximum male capture by the natural sex pheromone occurred from 1000 to 1100 AM at air and soil temperatures of 30.0°C and relative humidity of 57.0%. As these temperatures increased, females burrowed into the soil, as they are more sensitive to heat than males. Thus, it was concluded that sex pheromone-mediated mating in this cerambycid is directly affected by temperatures of air and soil.     

Porapak-Q collection of pheromone components and isolation of (Z)- and (E)-14-methyl-8-hexadecenal,sex pheromone components,from the females of four species ofTrogoderma (Coleoptera: Dermestidae)

A major sex pheromone component of each of fourTrogoderma species was isolated by aeration of the female beetles and absorption of the volatiles on Porapak-Q. (Z)-14-Methyl-8-hexadecenal was identified as the major component inT. inclusum andT. variabile, and (E)-14-methyl-8-hexadecenal was identified inT. glabrum. Both (Z)- and (E)-14-methyl-8-hexadecenal were found inT. granarium (Khapra beetle), in the ratio 92Z8E. In laboratory bioassays, male beetles exhibited arousal and mating responses to the aldehydes, and could discriminate between the geometric isomers. The daily production of the aldehyde was calculated for each species, and other active components were detected. These aeration-absorption studies contrast with earlier studies on macerated beetles, in which the aldehyde was not detected. The efficacy of the aeration-absorption system for collection of the sex pheromones is also described. The absorbent (Porapak-Q) efficiently collected the active pheromone; only minor amounts of activity were left in the other parts of the system.     

Sexually dimorphic setiferous sex patch in the male red flour beetle,Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae): Site of aggregation pheromone production

Evidence for the existence of a male-produced aggregation pheromone secreted from the prothoracic femoral setiferous sex patch ofTribolium castaneum is reported. Both sexes were attracted toca. 60 ng of crude secretion. Males and females perceive the pheromone on the day of emergence while perception differs between the sexes: male response reaches a maximum on day 1 posteclosion, when tested at <1, 1, and 30 days; females show a maximum response at 30 days posteclosion. Behavioral responses to pheromone odors and a complex Chromatographic profile are reported.Supported in part by a Graduate Student Alumni Research Award from the Graduate School, The Ohio State University; the National Science Foundation; and the College of Agriculture and Life Sciences, University of Wisconsin, Madison, Wisconsin.Dedicated to Dr. Alexander Sokoloff for his monumental contributions to the studies onTribolium and upon the occasion of his 60th birthday.     

3-methyl-3-buten-1-ol: An aggregation pheromone of the four-eyed spruce bark beetle,Polygraphus rufipennis (Kirby) (Coleoptera: Scolytidae)

Porapak Q-captured volatiles of malePolygraphus rufipennis (Kirby) boring in black spruce and white spruce from Newfoundland and British Columbia, respectively, contained 3-methyl-3-buten-1-ol. Volatiles from logs in which the males had been joined by females contained the compound in reduced quantities. Hindgut extracts from male and femaleP. rufipennis disclosed no male-specific volatiles, but 3-methyl-3-buten-1-ol was detected in extracts of male-produced frass. The compound was not present in extracts from fresh phloem tissue.P. rufipennis of both sexes responded strongly in the field to traps baited with 3-methyl-3-buten-1-ol released at 4390 g/day. There was little response to unbaited traps, fresh uninfested black spruce logs, or to 3-methyl-3-buten-1-ol released at lower rates. Combination of 3-methyl-3-buten-1-ol with either one of five terpenes prevalent in black spruce did not enhance beetle catch. Approximately half of 20 black spruce trees baited with 3-methyl-3-buten-1-ol were attacked, compared to 20.0% of 10 unbaited control trees. This new aggregation pheromone could be used to monitor or manageP. rufipennis populations.     

Interspecific activity of semiochemicals among sibling species ofPissodes (Coleoptera: Curculionidae)

Pissodes strobi, P. approximatus, andP. nemorensis are sibling species of pine weevils that can hybridize in the laboratory but are presumed to be reproductively isolated in nature. Males of all three species produce the terpenoids grandisol and grandisal; these compounds serve as an aggregation pheromone forP. approximatus andP. nemorensis when deployed with odors from pine bolts. A series of field experiments examined the possibility of cross-attraction among the three species. Tests in New York and Florida found that parapatrically distributedP. approximatus andP. nemorensis were cross-attractive, but different photoperiodic conditioning was required for pheromone production in males of the two species. Long-day pheromone production (P. approximatus-type.) was inherited in interspecific hybrids. Other tests showed thatP. strobi males, or hybrid males from crosses ofP. strobi withP. approximatus, were not attractive to sympatricP. approximatus. When the response ofP. strobi was assessed to males of eitherP. strobi orP. approximatus confined on white pine leaders (the breeding site ofP. strobi), no evidence of cross-attraction or pheromone activity was found;P. strobi were caught in equal numbers onP. strobi-baited leaders,P. approximatus-baited leaders, and unbaited leaders. Tests of interspecific interactions found that maleP. strobi produce an allelochemical signal that interrupts the response ofP. approximatus to its natural or synthetic aggregation pheromone. This interspecific response is apparently adaptive for members of both species (classified as an allomone-kairomone or synomone) because it may ultimately serve to prevent interspecific matings that would lower the fitness of the parents.     

Flight and landing behavior ofTrypodendron lineatum (Coleoptera: Scolytidae) in response to different semiochemicals

The responses of the striped ambrosia beetle,Trypodendron lineatum (Olivier) (Coleoptera: Scolytidae), to modified drainpipe traps baited with the host attractant ethanol, the aggregation pheromone lineatin, both alone and in combination, were studied in a wind tunnel. Exposure of males to ethanol increased their frequency of steady, upwind flight; however, only lineatin was effective in inducing them to land on and enter the traps. In contrast, exposure of females to either ethanol or lineatin alone resulted in an increased frequency of trap landing and entry. Both compounds released simultaneously did not significantly increase the frequency of trap landing and entry for either sex. These responses are consistent with the life history strategies used by both sexes to seek and colonize suitable host material.     

Identification and synthesis of female sex pheromone of Oriental beetle,Anomala orientalis (Coleoptera: Scarabaeidae)

Females of the Oriental beetle,Anomala orientalis (Waterhouse), release a sex pheromone composed of a 9:1 blend of (Z)- and (E)-7-tetradecen-2-one. The double-bond position of the pheromone was determined by DMDS derivatization and interpretation of the fragmentation patterns produced by monounsaturated ketones. In a sustained-flight tunnel, males responded by flying toward female beetles and attempting to copulate with them. Both effluvium and whole-body extracts of OB females were analyzed, and the activity was found only in the airborne extracts. Flight-tunnel bioassays also showed that a synthetic 90:10Z/E blend on a rubber septum was attractive and that the responses of males to this blend were equivalent toZ isomer alone, but much better than to the singleE isomer.     

Sex pheromone biology and behavior of the cowpea weevilCallosobruchus maculatus (Coleoptera: Bruchidae)

Female cowpea weevils,Callosobruchus maculatus (F.), emitted a pheromone which excited males. Pheromone release began soon after emergence and continued for one week. Synchronization of pheromone release with calling behavior was demonstrated. Mating reduced pheromone release but not male response. Pheromone obtained by aeration collection was utilized for determining a quantitative dose-response relationship.Mention of a commercial product does not constitute an endorsement by the USDA.Visiting scholar on leave from Shanghai Institute of Entomology, PRC.     

Field evaluation ofAnomala schonfeldti ohaus (Coleoptera: Scarabaeidae) synthetic sex pheromone

Synthetic 2-(E)-nonenol, previously identified as the sex pheromone ofAnomala schonfeldti (Coleoptera: Scarabaeidae), is demonstrated to be very attractive to males in the field. Nevertheless, no significant differences were found between treatments with 1, 5, 10, and 20 mg dosages. Males ofA. schonfeldti were more significantly attracted to traps at 30 cm high than at 90 cm. Although the observed behavior seemed to indicate a trend of more attraction to buried traps than those placed at 30 cm, there was no statistical difference between the two treatments. Pheromone-baited traps caught significantly more beetles than traps containing three virgin females. Over 70% of released beetles were recaptured in six traps surrounding the point of release and separated from each other by 50 m, suggesting a possible use of the pheromone (in combination with floral compounds) in mass trapping.