Allelochemical resistance of bald cypress,Taxodium distichum,heartwood to the subterranean termite,Coptotermes formosanus

The heartwood of bald cypress,Taxodium distichum (L.) Rich., resisted feeding attack by the Formosan subterranean termite,Coptotermes formosanus Shiraki. Hexane-extracted heartwood, however, was consumed at > 12 times the amount of sound heartwood eaten. A bioassay usingT. distichum sapwood as a feeding substrate was employed to assess the antitermitic activity of successive hexane, acetone, and methanol extracts of heartwood shavings and isolates derived from the active hexane extract. Two fractions, eluted from the crude hexane extract by liquid chromatography, significantly reduced termite feeding compared to the parent extract, while a third fraction was less active than the original hexane extract. Each fraction contained one major component. All three components were structurally related diterpenes. The two most active heartwood constituents were identified by GC-MS and NMR as ferruginol and manool, while the third and least active, but most prevalent, compound in heartwood was identified as nezukol. Results of bioassays suggest that these allelochemicals act principally as feeding deterrents with accompanying termite mortality due to starvation.     

Identification of a male-produced pheromone ofAnticarsia gemmatalis (Hübner) (Lepidoptera; Noctuidae) attractive to conspecific males

Observations in the laboratory and in the field indicated that maleAnticarsia gemmatalis (Hübner), the velvetbean caterpillar (VBC), are attracted to conspecific courting males. Male VBC subsequently were found to be attracted to extracts of male abdominal tips including the extrudable hairpencils. The active chemical in these extracts was identified as (Z,Z,Z)-3,6,9-heneicosatriene, which is also one of the major components of the female VBC sex pheromone. Male VBC in a wind tunnel and in the field exhibited a bimodal response distribution to a range of ratios of the (Z,Z,Z)-3,6,9-heneicosatriene and (Z,Z,Z)-3,6,9-eicosatriene, with one maximum at the pure heneicosatriene alone and the other at the 6040 female blend. This demonstrates that the male response to the male hairpencil component is distinct from that to the female sex pheromone.This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or the recommendation for its use by USDA.     

Sex pheromone components of the giant looper,Boarmia selenaria schiff. (Lepidoptera: Geometridae): Identification,synthesis, electrophysiological evaluation,and behavioral activity

(Z,Z)-6,9-cis-(3S,4R)-Epoxynonadecadiene9a and (Z,Z,Z)-3,6,9-nonadecatriene have been identified as sex pheromone components in female ovipositor extracts and effluvia of the geometridBoarmia selenaria. The identification was based on relative retention times on gas chromatographic columns, GC-MS, chemical enantioselective syntheses, EAG, wind-tunnel behavioral experiments, and field tests. A single female ovipositor extract contained an average of 42 ng of (Z,Z)-6,9-cis-3,4-epoxynonadecadiene and 2 ng of (Z,Z,Z)-3,6,9-nonadecatriene.EAG, wind-tunnel behavioral studies, and field tests demonstrated that maleB. selenaria exhibit preferential attraction for the (3S,4R)-enantiomer of (Z,Z)-6,9-cis-3,4-epoxynonadecadiene. Only in effluvia and ovipositor extracts of calling females was (Z,Z)-6,9-cis- 3,4-epoxynonadecadiene detected, whereas relatively high amounts of (Z,Z,Z)-3,6,9-nonadecatriene were found in noncalling females. Wind-tunnel behavioral studies showed that (Z,Z,Z)-3,6,9-nonadecatriene did not elicit any response in the males, and when tested in combination with a mixture of monoepoxynonadecadienes, (Z,Z,Z)-3,6,9-nonadecatriene decreased the observed behavioral responses. A possible precursor role for (Z,Z,Z)-3,6,9-nonadecatriene in the pheromonal system is discussed.     

Sustained Production of the Labile Pheromone Component, (Z,Z)-6,9-Heneicosadien-11-one, from a Stable Precursor for Monitoring the Whitemarked Tussock Moth

The principal sex pheromone component of the whitemarked tussock moth (WMTM), Orgyia leucostigma, was recently identified as (Z,Z)-6,9-heneicosadien-11-one (Z6Z9-11-one-21Hy). However, it is thermally unstable and quickly degrades under field conditions so that baited traps are effective for only one night. We have developed a solution to this problem that combines two techniques: (1) the use of a stable pheromone precursor, (Z,Z)-6,9-heneicosadien-11-one ethylene ketal, which is hydrolyzed to the dienone by an acidic aqueous solution (2% p-toluenesulfonic acid in 35% aqueous sorbitol), and (2) use of a small, off-the-shelf, autonomous pump (the Med-e-Cell Infu-disk™) to deliver the precursor continuously to a suitable substrate where it is converted rapidly into the attractive dienone pheromone component. The pump and hydrolysis substrate fit inside sticky traps and because generation and release of pheromone is continuous, the instability of the pheromone is not an issue. In electroantennogram bioassays, dose-dependent responses were obtained with 1 to 1000 ng of hydrolyzed ketal on filter paper, but no response was obtained to 1000 ng of the ketal itself. In wind tunnel bioassays, males were attracted to lures emitting the dienone pheromone component generated from 0.1 to 100 ng of the hydrolyzed ketal. Field tests in 2004 and 2005 showed that sticky traps fitted with the pump delivering the ketal (0.1–1 μg/μL in heptane) at 10 μL/hr to a cotton pad soaked with the hydrolyzing solution were attractive to male WMTM. No moths were caught in controls or traps baited with (Z)-6-heneicosen-11-one. An average of 0.51 moths per trap night was caught over an 18-night period in 2005. The results represent a first step toward developing a sensitive and practical monitoring tool for the WMTM by using a ketal precursor of its unstable dienone pheromone component.     

Use of a sex attractant and an inhibitor for monitoring winter moth and bruce spanworm populations

A single sex pherormone component was isolated from abdominal tip extracts of female Bruce spanworm.Operophtera bruceata (Hulst). This was identified as (Z,Z,Z)-1,3,6,9-nonadecatetraene by capillary gas chromatography (GC), electroantennography, and mass spectrometry. In addition, hexane extracts of female abdominal tips from Bruce spanworm and the winter moth.O. brumata L., were analyzed by GC coupled to an electroantennographic detector (GC-EAD). The extracts ofO. bruceata andO. brumata females elicited only a single response, at the same retention time, from antennae of their conspecific and reciprocal males. In field tests conducted in Saskatchewan, traps baited with the synthetic tetraene captured Bruce spanworm males. In tests carried out on Vancouver Island, British Columbia, where the two species coexist, both Bruce spanworm and winter moth males were captured. The attractancy of lures containing the synthetic pheromone alone and in combination with several structurally related analogs was field tested at both locations. One of these, an isomer of the natural pheromone, (E,Z,Z)-1,3,6,9-nonadecatetraene, inhibited the capture of Bruce spanworm males but had no effect upon the number of winter moth males which were taken. Thus, populations of these two very similar species can be distinguished by employing traps baited with pheromone ± the inhibitor. Coneorifice Hara traps were found useful for field trapping males of both species.Issued as NRCC No. 26107     

Enantiomers of (Z,Z)-6,9-Heneicosadien-11-OL: Sex Pheromone Components of Orgyia detrita

(6Z,9Z,11S)-6,9-Heneicosadien-11-ol (Z6Z9-11S-ol-C21) and (6Z,9Z,11R)-6,9-heneicosadien-11-ol (Z6Z9-11R-ol-C21) were identified as major sex pheromone components of female tussock moths, Orgyia detritaGuérin-Méneville (Lepidoptera: Lymantriidae), on the basis of (1) analyses of pheromone gland extracts of female O. detrita by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC mass spectrometry, and (2) field trapping experiments with synthetic standards. Z6Z9-11S-ol-C21 and Z6Z9-11R-ol-C21 in combination, but not singly, attracted significant numbers of male moths. Racemic Z6Z9-11-ol-C21 was more attractive than the 1:3.5 (R:S) blend ratio found in pheromone gland extracts from female moths. Lower and higher homologues of Z6Z9-11-ol-C21 were also detected in GC-EAD recordings of pheromone extracts, and the racemic compounds enhanced attractiveness of Z6Z9-11-ol-C21 in field experiments. Because of trace amounts of these homologues in extracts, their enantiomeric composition could not be determined. This is the first report of secondary alcohols as pheromone components in the ditrysian (advanced) Lepidoptera.     

Sex pheromone components of three species ofSemiothisa (Geometridae), (Z,Z,Z)-3,6,9-heptadecatriene and two monoepoxydiene analogs

Adult males ofSemiothisa signaria dispuncta (Walker) were attracted to field traps baited with (Z,Z,Z)-3,6,9-octadecatriene and (Z,Z)-6,9-cis-3,4-epoxy-octadecadiene. However, analyses of sex pheromone gland extracts of females of this species by GC-MS and by GC in combination with an electroantennograph detector (GC-EAD) showed the pheromone to be comprised of a mixture of the next lower homologs: (Z,Z,Z)-3,6,9-heptadecatriene and (Z,Z)-6,9-cis-3,4-epoxy-heptadecadiene. Blends of these two C₁₇ compounds were subsequently found to be more attractive to males in the field than the corresponding C₁₈ mixtures. Sex pheromones of two otherSemiothisa species were also found to contain C₁₇ components. (Z,Z,Z)-3,6,9-Heptadecatriene, detected by GC-EAD analysis of a female abdominal tip extract ofS. bicolorata (Fabricius), attracted conspecific males, and this attraction was significantly reduced by additions of (Z,Z)-6,9-cis-3,4-epoxyheptadecadiene, the major pheromone component ofS. signaria dispuncta, to the lure. (Z,Z)-3,9-cis-6,7-Epoxy-heptadecadiene was detected by GC-EAD analysis as the primary male antennal stimulatory component present in abdominal tip extracts ofS. ulsterata (Pearsall), and males of this species were attracted to traps baited with this epoxide. Each of these three C₁₇ compounds constitute previously unknown lepidopteran sex pheromone components. Blends of (Z,Z, Z)-3,6,9-heptadecatriene and (Z,Z)-3,9-cis-6,7-epoxyheptadecadiene attracted males of a fourth species,S. delectata Hulst, but no females of this species were obtained to permit analysis of its sex pheromone. The occurrence of (Z,Z,Z)-3,6,9-heptadecatriene inS. neptaria (Guenee) females was indicated by GC-MS analysis of an abdominal tip extract; however, no males were attracted to any of the fielded mixtures containing this hydrocarbon.     

Host-location kairomone fromPeriplaneta americana (L.) for parasitoidAprostocetus hagenowii (Ratzeburg)

Chemically mediated host location in the eulophid parasitoidAprostocetus hagenowii (Ratzeburg) was investigated. In Y-tube bioassays 77.6% of female parasitoids responded to aPeriplaneta americana (L.) ootheca; parasitoids did not respond to air with no volatile stimuli. Frass from adult cockroaches was as attractive as an ootheca. Bioassay of one ootheca equivalent of five lipid fractions (eluted with hexane and 1, 5, 10, and 30% ether in hexane) from silica gel column chromatography indicated that the active component was a hydrocarbon. Further separation and bioassay of oothecal hydrocarbons by AgNO₃-impregnated silica gel column chromatography indicated that the biological activity was in one fraction. Gas chromatographic (GC) analysis of this fraction revealed a single peak; this peak was identified by researchers in 1963, 1969, and 1972 as (Z,Z)-6,9-heptacosadiene. Qualitative and quantitative GC analyses of total hydrocarbons from oothecae, frass, and adult females were essentially identical; 6,9-heptacosadiene was the dominant hydrocarbon from each source. The alkadiene was 37 times more abundant in frass than on the ootheca. The volatilization of the alkadiene from oothecae was demonstrated by aeration and trapping on Super Q adsorbent. The current study is the first evidence for biological activity of (Z,Z)-6,9-heptacosadiene, a major hydrocarbon component on adult female American cockroaches, on their oothecae, and in their frass.This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation for its use by the USDA or the University of Florida.     

Sabulodes caberata guenée (Lepidoptera: Geometridae)

A 6,9-nonadecadiene, (Z)-9-nonadecene, andn-nonadecane were identified in extracts of sex pheromone glands of femaleSabulodes caberata Guenée. Potential pheromonal activity of gland components was assessed by electroantennogram measurements of gas-chromatographic fractions of abdominal tip extracts. Chemical identification was based on gas chromatography and mass spectrometry of parent compounds, hydrogenation products, ozonolysis products, dimethyl disulfide adducts, and synthesis. The monoene was synthesized via coupling of alkyl and acetylenic intermediates. (Z,Z)-6,9-Nonadecadiene (Z6,Z9-19H) was synthesized from methyl linoleate via chain lengthening. SyntheticZ6,Z9-19H had the same retention times on polar and nonpolar capillary gas-chromatographic columns as the 6,9-nonadecadiene from the sex pheromone glands. In field testsZ6,Z9-19:H alone produced trap catch of maleS. caberata and addition of (Z)-9-nonadecene orn-nonadecane had no effect on trap catch.This paper reports the results of research only. Mention of a commercial product in this paper does not constitute a recommendation by the U.S. Department of Agriculture.     

Identification of sex pheromone ofTetanolita mynesalis (Lepidoptera: Noctuidae), a prey species of bolas spider,Mastophora hutchinsoni

The bolas spider,Mastophora hutchinsoni, attracts adult males of four species of nocturnally active Lepidoptera through aggressive chemical mimicry of those species' sex pheromones. Here we report the identification of the sex pheromone of one prey species, the smoky tetanolita (Tetanolita mynesalis). In sex pheromone gland extracts, only two peaks stimulated an electrophysiological response as measured by a coupled gas chromatography-electroantennographic detection analysis. These two peaks had retention times identical to (3Z,6Z,9Z)-heneicosatriene (3Z,6Z,9Z-21:H) and (3Z,9Z)-cis-6,7-epoxy-heneicosadiene (3Z,9Z-cis-6,7-epoxy-21:H), respectively, and mass spectra identical to these two compounds. It was determined that 0.23±0.16 and 0.56±0.26 ng of 3Z,6Z,9Z-21:H and 3Z,9Z-cis-6,7-epoxy-21:H, respectively, were present in pheromone gland extracts from individual females. A 1:1 blend of 3Z,6Z,9Z-21:H and 3Z,9Z-6S,7R-epoxy-21:H was an effective attractant for adult males from feral populations. Blend ratios of these two components from 2:1 to 1:2 were equally effective as attractants. Greater deviation from the optimal blends resulted in diminished trap catches. The enantiomer 3Z,9Z-6R,7S-epoxy-21:H not only was not effective in attracting males, its presence in the effective blend shut down trap catches. These results indicate that the pheromone blend consists of 3Z,6Z,9Z-21:H and 3Z,9Z-6S,7R-epoxy-21:H. This is the first report of a hydrocarbon/epoxide pheromone for a prey species of this bolas spider. Sex attractants or pheromones for the other three prey species are composed of aldehydes or acetates.     

Antioxidant effect of the constituents of susabinori (Porphyra yezoensis)

The antioxidant activities of several extracts from Susabinori (Porphyra yezoensis) were measured by the ferric thiocyanate method and the thiobarbituric acid method. The methanol, acetone, ethyl acetate, and hexane extracts, and the chloroform-soluble and water-soluble fractions from the chloroform-methanol extract exhibited higher activities than α-tocopherol. The hot water extract showed little activity. Thin-layer chromatography analysis of the active extracts suggested the existence of several antioxidants. The activity of the chloroform soluble fraction was due to chlorophyll analogs. A strong antioxidant was isolated from the methanol extract, accompanied by several amino acids such as leucine and phenylalanine. This compound was identified as usujilene, a kind of mycosporine-glycine like amino acid.     

Abraxas grossulariata L. (Lepidoptera: Geometridae): Identification of (3Z,6Z,9Z)-3,6,9-heptadecatriene and (6Z,9Z)-6,9-cis-3,4-epoxyheptadecadiene in the female sex pheromone

(3Z,6Z,9Z)-3,6,9-Heptadecatriene and (6Z,9Z)-6,9-cis-3,4-epoxyheptadecadiene have been identified in female sex pheromone gland extracts ofAbraxas grossulariata L. (Lepidoptera: Geometridae). The compounds were detected by gas chromatography with electroantennographic detection (GC-EAD) and identified by GC-mass spectrometry (GC-MS). The amounts of hydrocarbon and epoxide were 0.13 and 0.42 ng/female, respectively. These identifications were confirmed by synthesis; the absolute configuration of the epoxide remains to be determined. Another isomeric epoxide, (3Z,6Z)-3,6-cis-9,10-epoxyheptadecadiene, was tentatively identified in small amounts (0.04 ng/female). Racemic (6Z,9Z)-6,9-cis-3,4-epoxyheptadecadiene elicited the largest electroantennogram response within a series of heptadecadiene and nonadecadiene monoepoxides and the corresponding trienic hydrocarbons and, in field tests, attracted maleA. grossulariata into traps. Addition of 10% (3Z,6Z,9Z)-3,6,9-heptadecatriene to this epoxide enhanced attractiveness; addition of (3Z,6Z)-3,6-cis-9,10-epoxyheptadecadiene had no effect at low proportions while higher proportions caused a reduction in the numbers of males caught.     

Identification of trail pheromone precursors from Subterranean termite,Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)

Whole-body extracts of the termite,Coptotermes formosanus Shiraki served for examining the presence of trail pheromone precursor(s). Three trail pheromone precursor candidates, identified as dodecatrienyl stearate, dodecatrienyl oleate, and dodecatrienyl linoleate, were isolated using various chromatographic methods in conjunction with bioassay and by capillary GC-MS analyses.     

Stereospecific synthesis of (Z,Z)-11,13-hexadecadienal,a female sex pheromone of the navel orangeworm,Amyelois transitella (Lepidoptera: Pyralidae)

A synthesis of (Z,Z)-11,13-hexadecadienal, a compound previously identified as the major component of the sex pheromone of the female navel orangeworm,Amyelois transitella (Walker), is described. The key step is the reduction of an unsymmetrical conjugated diyne with dicyclohexylborane. This reduction produced theZ,Z isomer with less than 0.5% total of other isomers.Mention of a commercial or proprietary product in this paper does not constitute endorsement of that product by the USDA.     

Sex pheromone ofStenoma cecropia Meyrick (Lepidoptera: Elachistidae)

(Z,E)-9,11-tetradecadienal (Z9,E11–14: Ald; 11%), (Z,E)-9,11,13-tetradecatrienal (Z9,E11, 13–14: Ald; 67%), (Z,E)-9,11-tetradecadienyl acetate (Z9,E11–14: Ac, 5.5%), and (Z,E)-9,11,13-tetradecatrienyl acetate (Z9,E11,13–14: Ac; 16.5%) were identified in the extracts of female pheromone glands ofStenoma cecropia (Lepidoptera: Elachistidae). From electroantennograms and single sensillum recordings, receptors toZ9,E11,13–14:Ald andZ9,E11–14: Ald were found on male antenna. Behavioral data were obtained from olfactometric tests in the laboratory and field trapping experiments in Colombia. It appeared that a blend ofZ9,E11,13–14:Ald (83%) andZ9,E11–14:Ald (17%) was attractive to males. These aldehydes are assumed to be components of the sex pheromone ofS. cecropia, whereas the acetates found in gland extracts might be precursors of the pheromone.     

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.Mention of a commercial or proprietary product in this paper does not constitute an endorsement of that product by the USDA. Accepted for publication February 28, 1979.     

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.     

(Z,E)-3,5-Tetradecadien-1-ol acetate sex attractant for the carpenterworm moth,prionoxystus robiniae (peck) (Lepidoptera: Cossidae)

Electroantennogram analyses of female gland extract and of male antennal responses to synthetic standards suggested that (Z,E)-3,5-tetradecadien-1-ol acetate is a pheromone component for the carpenterworm moth,Prionoxystus robiniae (Peck). The four 3,5-geometrical isomers were synthesized and bioassayed in the laboratory and the field in 1972, 1973, and 1974. TheZ,E isomer was found to be active in the laboratory and a good attractant in the field. The synthesis of theZ,E isomer also produced considerable quantities of theE,E isomer, which is difficult to remove completely. TheE,E isomer does not inhibit the response of males to theZ,E isomer when it is present in amounts up to 20% of theZ,E isomer. The addition of a keeper, a volatility modifier, or an antioxidant prolonged the activity of the attractant for as much as 43 days. (Z,E)-3,5-Tetradecadien-1-ol acetate may be a natural pheromone, but it has not been chemically defined from female extract. There is EAG evidence that a second pheromonal component may be present. The attractant nevertheless provides a tool for population survey, behavioral studies, evaluation of economic impact, and possibly control.     

Sex Pheromone of the Persimmon Fruit Moth, Stathmopoda masinissa: Identification and Laboratory Bioassay of (4E, 6Z)-4,6-Hexadecadien-1-ol Derivatives

Three electroantennogram (EAG)-active components were detected by gas chromatography coupled to an electroantennographic detector (GC–EAD) analysis of a hexane extract of the pheromone glands of the persimmon fruit moth, Stathmopoda masinissa. These compounds were identified as (4E,6Z)-4,6-hexadecadienal (E4,Z6-16:Ald) and the corresponding acetate (E4,Z6-16: OAc) and alcohol (E4,Z6-16:OH) by mass spectral, GC retention time (RT), and microchemical test data. The characteristic base peak of the aldehyde at m/z 84 provided a crucial piece of information suggesting the possibility of a 4,6-diene structure. The (4E,6Z)-isomer elicited the strongest EAG responses among the four geometrical isomers of each synthetic 4,6-hexadecadienyl compound. In a laboratory bioassay, only E4,Z6-16:OAc elicited male moth behavioral activity significantly different from the control; the activity of the acetate was not affected by addition of the aldehyde and alcohol. A preliminary field trial confirmed that E4,Z6-16:OAc as a single component attracted male moths. The possible roles of E4,Z6-16:Ald and E4,Z6-16:OH as components of lures for field use remain to be determined.     

Multicomponent sex pheromone inMacrocentrus grandii Goidanich (Hymenoptera: Braconidae)

A multicomponent sex pheromone inMacrocentms grandii Goidanich (Hymenoptera: Braconidae) was demonstrated using wind-tunnel and field bioassays. In wind-tunnel bioassays, three Florisii fractions from female wasps (hexane, 5%, and 50% ether in hexane) and one from male wasps (50% ether in hexane) were attractive to males. The hexane and 5% ether in hexane fractions each elicited similar male behavioral responses. These included upwind anemotaxis, casting, landing on the source, wing fanning, and mating attempts between males. The 50% ether in hexane fraction, whether male- or female-derived, initiated a strong flight response by males but few landings on the source. In addition, the 50% ether in hexane fraction was found to synergize strongly the hexane fraction. All females tested in the wind tunnel gave no responses to male- or female-derived extracts. Field tests generally supported the wind-tunnel results, although no field attraction was observed for the 5% ether in hexane fraction.