Sex pheromone components of corn stalk borerSesamia nonagriodes (Lef.) isolation,identification, and field tests

Z-11-Hexadecenyl acetate (Z11–16OAc), dodecyl acetate (12OAc),Z-11-hexadecenal (Z11–16Aid), andZ-11-hexadecenol (Z11– 16OH), were found in pheromone gland extracts of femaleSesamia nonagriodes (Lef.) [Lepidoptera: Noctuidae]. These four components were also present in airborne volatiles collected from calling virgin females in a 651889 ratio. Hexadecyl acetate (16OAc) was also detected but found to be inactive. The identification was based on multicolumn GC analysis, mass spectrometry, and field activity.Z11–16OAc is the major sex pheromone component; the addition of the secondary components individually decreased male captures. The blend of the four synthetic components in 691588 ratio was highly attractive to males; 200 g per trap was the most effective concentration in field tests.Lepidoptera: Noctuidae     

Aggregation pheromone characterization and comparison inDrosophila ananassae andDrosophila bipectinata

(Z)-11-Octadecenyl acetate (Z11–18Ac) and (Z)-11-eicosenyl acetate (Z11–20Ac) were identified as the aggregation pheromones ofDrosophila ananassae, andZ11–20Ac was identified as the aggregation pheromone ofDrosophila bipectinata. Z11–18Ac andZ11–20Ac were not attractive alone; however, in combination with fermenting food odors, the acetates attracted flies of both sexes in a wind-tunnel olfactometer. The pheromones were present in the ejaculatory bulb of sexually mature male flies and transferred to the female during mating. MaleD. bipectinata released little if anyZ11–20Ac to the food; however, recently mated females releasedZ11–20Ac to the surrounding surfaces in just a few hours after mating.D. ananassae males, on the other hand, appeared to release moreZ11–18Ac andZ11–20Ac to the surroundings than mated females. AlthoughD. bipectinata males had noZ11–18Ac, flies were as attracted toZ11–18Ac as to an equal quantity ofZ11–20Ac.D. ananassae were attracted toZ11–18Ac but not toZ11–16Ac orZ11–20Ac. However,Z11–20Ac in combination withZ11–18Ac was significantly more attractive thanZ11–18Ac alone.     

Effects of dodecyl acetate andZ-10-tridecenyl acetate on attraction ofEupoecilia ambiguella males to the main sex pheromone component,Z-9-Dodecenyl acetate

Attraction ofE. ambiguella males toZ-9-dodecenyl acetate (Z9-12Ac), alone and in combination with dodecyl acetate (12Ac) orZ-10-tridecenyl acetate (Z10-13Ac) was tested in both wind-tunnel and field experiments. In the laboratory, response toZ9-12Ac reached a distinct dosage optimum at which attraction was nearly as good as to live females. Addition of 12Ac, a minor component of female glands and effluvia, had no effect at low doses ofZ9-12Ac and only marginally improved attraction at the optimum. However, inclusion of 12Ac with an overdose ofZ9-12 Ac fully restored activity. In the field,Z9-12Ac alone was not very attractive at any dose; catches markedly increased by adding 12Ac and climbed with increasing dose of each compound up to 10 mg. Optimum ratio ofZ9-12Ac to 12Ac was 11 to 15. Another compound,Z10-13Ac, had the same effect as 12Ac in the laboratory and the field but was effective at a lower dose. In the field, inclusion of the synergist permits use of high cap loads to attract more males, perhaps from greater distances.     

Identification of sex pheromones of two sibling species in dingy cutworm complex,Feltia jaculifera (GN.) (Lepidoptera: Noctuidae)

The sex pheromone components of the two sibling species of the dingy cutworm that occur on the prairies of western Canada were identified in abdomen-tip extracts from calling female moths. Three monounsaturated acetates, (Z)-7-dodecenyl acetate, (Z)-9-tetradecenyl acetate, and (Z)-11-hexadecenyl acetate, are common to both species in ratios of 100133 for species A and 0.30.5100 for species B. The most effective synthetic blends for the attraction of male moths in the field consisted of these three components in ratios of 1010 at 8.8g/lure for species A and 112000 at 500g/lure for species B. The addition of Z5-12Ac to either blend reduced the catches and the addition of Z7-12OH orZ11-16OH to the three-component blend reduced the catches of species B males. The species are morphologically indistinguishable, but the identity of the males attracted to the synthetic blends could be confirmed by their antennal responses to a test blend of the three components using a GC-EAD system. Both synthetic attractant blends are competitive with females and will be useful for studying the distribution, biology, and relative abundances of the two species.Contribution no. 3879005 of the Lethbridge Research Station.     

Attraction ofCacoecimorpha pronubana male moths to synthetic sex pheromone blends in the wind tunnel

Attraction ofCacoecimorpha pronubana male moths to blends of four sex pheromone components was studied in the wind tunnel.Z11–14Ac alone did not elicit upwind flight, admixture of 10%Z11–14OH or more led to successful attraction of males to the source. Attractivity of these binary blends was further enhanced by addition ofE11–14Ac orZ9–14Ac; the optimum was a blend ofZ11–14Ac,Z11–14OH,E11–14Ac, andZ9–14Ac at the proportion of 1003033. In ternary and quaternary blends, the effect ofZ11–14OH andE11–14Ac was strongest at 30% and 3%, respectively. By contrast,Z9–14Ac increased behavioral responses over a wide range.     

A four-component pheromone blend for optimum attraction of redbacked cutworm males,Euxoa ochrogaster (Guenée)

Four acetates,Z-5-decenyl acetate,Z-5-,Z-7-, andZ-9-dodecenyl acetates, in microgram ratios of 120021 or 120062 were excellent, specific sex pheromone blends for capturing male redbacked cutworm moths in cone traps. Blends in ratios of 120021 and 220021 at 1000 g/ rubber septum dispenser remained highly effective for 6 weeks under field conditions. The essential minor components,Z-5-decenyl,Z-7-, andZ-9-dodecenyl acetates, became inhibitory at concentrations of about 10% in the blends, and this may be an important general phenomenon in lepidopteran pheromones. Blends involving a parapheromone,Z-5-undecenyl acetate, withZ-5-,Z-7-, andZ-9-dodecenyl acetate, in microgram ratios of 820021 or 2020062 were also excellent specific attractants for this species. TheZ-8-dodecenyl acetate had no obvious effect on the attraction of the redbacked cutworm males.     

Trail-following responses of the Argentine ant,Iridomyrmex humilis (Mayr), to a synthetic trail pheromone component and analogs

Behavioral evidence indicates that (Z)-9-hexadecenal (Z9-16ALD) is a trail pheromone component ofIridomyrmex humilis, and that the true trail pheromone may be multicomponent. Trail-following responses ofI. humilis workers to several concentrations of syntheticZ9-16ALD, a constituent of the Pavan's gland, were found to be comparable to responses to gaster extract trails containing ca. 100 times lessZ9-16ALD. Of the five aldehyde analogs tested, only (Z)-7-hexadecenal (Z7-16ALD) elicited significant trail-following. However, following responses to severalZ9-16ALD-Z7-16ALD combinations were lower than responses toZ9-16ALD alone. Trails on filter paper of biologically relevant concentrations ofZ9-16ALD lose activity within 2 hr in the laboratory. The release rate ofZ9-16ALD measured from filter paper trails was 0.25 ± 0.10 pg/cm-sec. This was used to estimate the trail-following threshold for this compound of Argentine ant workers.     

Response ofAedes triseriatus larvae to fatty acids ofCladophora

The activity of a methanol extract residue fromCladophora glomerata against larvae ofAedes triseriatus is confirmed. Fractionation of this residue by solubility in solvents of varying polarity is monitored by bioassay withA. triseriatus larvae. The presence of fatty acids in the active hexane soluble fraction and saponified material obtained therefrom is indicated by¹H NMR and IR. The identification of the individual fatty acids is achieved by co-injection and mass GLC of their methyl esters. Saturated and unsaturated fatty acids are screened against larvae and the LD₅₀ values of the most active acids are determined. The LD₅₀ of capric [100], lauric [120], myristic [140] and palmitoleic [161 (9c)] are 14,7, 4 and 3ppm respectively. The most active acids 120, 140 and 161 (9c) are present in all the fractions examined and are released to water by the powdered alga at pH 8.5.     

Sex pheromone ofEupoecilia ambiguella female: Analysis and male response to ternary blend

Sex gland extracts and washes ofEupoecilia ambiguella contain 10–20 ng/female of the primary sex pheromone componentZ-9-dodecenyl acetate (Z9–12Ac), accompanied by a number of related compounds. These areE-9-dodecenyl acetate (E9–12Ac),Z-9-dodecen-1-ol (Z9–12OH), saturated acetates of 12, 16, 18, and 20 carbons, and traces of a doubly unsaturated acetate, tentatively identified as a 9,11-dodecadienyl acetate. Octadecyl acetate predominates among the pheromone-related components, making up 1–2, occasionally 20–30 times the amount ofZ9–12Ac. The same compounds were also found in field-collected females and in effluvia.Z-9-Undecenyl acetate, which is a male attractant on its own, was also found in a sample of female effluvia. A hierarchy is observed in the ethological function of the pheromone components.Z9–12Ac is an attractant forE. ambiguella males. Dodecyl acetate (12Ac) is not attractive on its own but augments male catch when added to the main attractant. Addition of 18Ac augments attraction only when bothZ9–12Ac and 12Ac are present. Windtunnel tests demonstrate that 18Ac also raises the disorientation threshold, as previously shown for 12Ac. Other compounds, with the possible exception of additional saturated acetates, had either no effect on trap catch or, in the case ofE9–12Ac,Z9–12OH, andE-9,11-dodecadienyl acetate, were inhibitory above a certain level. A blend of roughly equal parts ofZ9–12Ac, 12Ac, and 18Ac provides the best attractant blend forE. ambiguella known to date.     

Apple ermine moth,Yponomeuta malinellus Zeller Two components of female sex pheromone gland highly effective in field trapping tests

When electroantennographic responses of maleYponomeuta malinellus Zeller to model compounds were determined at dosages of 0.3–30 ng, the strongest responses were obtained from (Z)-9-dodecen-1-ol acetate (Z9–12Ac). Also, strong responses were obtained from (Z)-11-tetradecenal (Z11–14A1) and (Z)-11-tetradecen-1-ol (Zl1–14OH). At a dosage of 0.3 ng,Z11–14A1 produced a stronger response thanZ11–14OH, while at a dosage of 30 ng,Z11–14OH andZ11–14A1 produced equal responses. Gas chromatographic and mass spectral analysis of extracts of female sex pheromone glands showed the presence ofZ9–12Ac, tetradecan-1-ol (14OH), (E)-11-tetradecen-1-ol (E11–14OH),Z11–14OH, hexadecan-1-ol, and hexadecan-1-ol acetate in a ratio of 0.62003710014035. In field tests,Z9–12Ac andZ11–14OH together were required for trap catch, and addition ofZ11–14A1,E11–14OH, 14OH, or (Z)-11-tetradecen-1-ol acetate did not increase catch. Ratios in rubber septa of 0.599.5 to 1.598.5 (Z9–12 Ac/Z11–14OH) captured the most males and captures were statistically equivalent for dosages of 10–1000 g/rubber septum. Traps baited with the synthetic lure produced better catches than those baited with females.Lepidoptera: Yponomeutidae.     

Influence of (Z)-11-hexadecen-1-ol on field performance ofHeliothis virescens pheromone in a PVC dispenser as evidenced by trap capture

Field studies were conducted to determine the effect of (Z)-11-hexadecen-1-ol (Z11-16 OH) on capture of tobacco budworm (TBW),Heliothis virescens (F.), males when added to two-component (HV-2) and six-component (HV-6) pheromone blends dispensed from a polyvinyl chloride (PVC) substrate. Numbers of males caught in traps baited with PVC dispensers containing 0.25% Z11-16 OH, relative to total pheromone content, were significantly higher than numbers caught with dispensers containing noZ11-16 OH. Catches of TBW were also increased significantly in some tests whenZ11-16 OH was formulated in the bait at a 1% concentration. Catches were significantly reduced with dispensers containing 5.95%Z11-16 OH compared with those containing noZ11-16 OH. There were no differences in catch between traps baited with HV-2 vs. HV-6 or HV-2 + 0.25%Z11-16 OH vs. HV-6 + 0.25%Z11-16 OH when formulated in PVC substrate.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA.     

Sex pheromone of the armyworm,Pseudaletia unipuncta (Haworth) (Lepidoptera: Noctuidae)

(Z)-11-Hexadecen-1-ol acetate (Z11–16Ac) free of theE isomer (<1%), hexadecan-1-ol acetate (16 Ac), and a hexadecen-1-ol [the (Z)-11 isomer based on the retention time on a Carbowax capillary column] were identified in extracts of the sex pheromone glands of adult virgin female armyworms,Pseudaletia unipuncta. Also, gas Chromatographic retention times on polar and nonpolar columns indicated the possible presence of (Z)-9-hexadecen-1-ol acetate (Z9–16Ac). The ratioZ11–16Ac/16Ac/Z11–16OH/Z9–16Ac was 10.150.130.02. Infield testsZ11–16 Ac was attractive alone, and the addition ofZ9–16Ac,Zll–16 OH, or 16 Ac singly or in combination in ratios found in the gland did not increase trap capture.Mention of a proprietary product does not constitute an endorsement of this product by the USDA.     

Comparative analysis of sex-pheromone-response antagonists in three races of European corn borer

Behavioral responses of males from three New York races of European corn borer,Ostrinia nubilalis (Hübner), to various suspected sexpheromone-response antagonists were investigated with a flight tunnel protocol. Males from a bivoltine (Z) race and from a univoltine (Z) race utilizing a natural pheromone blend of 982 (Z)-(E)-11-tetradecenyl acetates and males from a bivoltine (E) race utilizing a 199 (Z)-(E)-11-tetradecenyl acetate ratio were flown to their natural blends and to blends containing 1 % of one of the following additional compounds: Z9–12OAc,E9–12OAc,Z9–14OAc, andE9–14OAc. In each race, the added components lowered significantly the number of individuals completing the behavioral sequence. The only exception was bivoltineE males flown to a blend withE9–12OAc added. The number completing the sequence in this case was statistically not significantly lower than the number that completed the sequence to the standard blend. In all three races, theZ9–14OAc produced the most dramatic reduction in completed flights, and in the univoltineZ race, this added component was significantly more effective in reducing completed flights than any other added component. The response to the Z9–14OAc is understandable given recently published findings of an electrophysiological study of single sensilla in the European corn borer.     

Response of male potato stem borer moths,Hydraecia micacea (Esper) to conspecific females and synthetic pheromone blends in the laboratory and field

Behavior of males ofHydraecia micacea (Esper) responding to virgin females and to synthetic pheromone blends were investigated in a laboratory wind tunnel. The synthetic blend consisted of saturated 14Ac (68.9%),Z9–14Ac (3.4%),E11–14Ac (14.6%), andZ11–14Ac (13.1%). Virgin females were significantly better lures than the four-component synthetic blend for most behaviors. By deleting components individually from the four-component blend,Z9–14Ac,Z11–14Ac, and saturated 14Ac were found to be necessary for communication butE11–14Ac was found to have no effect on typical pheromone-mediated reproductive behaviors. Close-range studies suggested that chemicals of low volatility, released from moths, were important in eliciting copulation attempts. Field studies reinforced laboratory findings regarding the effectiveness of different lures and indicated thatHeliothis traps were the most effective for monitoring.     

Intraspecific variation and interspecific differences in sex pheromones of sibling species inCtenopseustis obliquana complex

The specific status ofCtenopseustis obliquana pheromone-types I, II, and III has been more fully examined. Females of types I and III produce a mixture of (Z)-8- and (Z)-5-tetradecenyl acetates (Z8-14:Ac, Z5-14: Ac). The previously reported different ratios of these two components in females of the two types (type I=8020, III=9010) have been reinvestigated. The median ratios of each type differed significantly, although there was some overlap in the ranges of these ratios. A field cage trial showed that males of type III are attracted to females of type I, so the observed differences may be ascribed to intraspecific variation. In contrast to females of types I or III, females of type II produce Z5-14Ac but no Z8-14Ac. The electroantennogram (EAG) profile of antennae of type II males shows a maximum response to Z5-14Ac, while the EAG profiles of types I and III show a strong response to Z8-14Ac. In wind tunnel tests using mixtures of these two compounds, type II males prefer blends consisting of all or mostly Z5-14: Ac, while type I males showed a preference to a mix of 70% Z8-14Ac plus 30% Z5-14Ac. We found that type I males are attracted to type I females when offered a choice between type I and type II females in a field cage test and that type II males similarly prefer type II females. Males of types I and II have specialist cells for Z8-14Ac and Z5-14Ac but differ with respect to relative densities of these cells and to further cell types responsive to other alkenyl acetates. Type IIC. obliquana is considered therefore a sibling species of types I and III. In addition, the amount of Z5-14Ac produced by type II females varied geographically. Females from the North Island produced significantly less (median=1.2 ng) Z5-14Ac than females from the South Island (median=2.2 ng). Type II populations in the North Island morphologically resembled sympatric type I, rather than type II from the South Island and are designated as type II (North Island). Type II (North Island) populations have so far been found only at Rukuhia (near Hamilton) and from Kerikeri. In contrast, type II populations are sympatric with type III populations over much of the South Island. In a field cage trial, males of types II and II (North Island) were attracted to females of both II and II (North Island). We tentatively ascribe the differences between type II and type II (North Island) to intraspecific variation.     

Identification and field testing of female-produced sex pheromone components of the spring cankerworm,Paleacrita vernata Peck (Lepidoptera: Geometridae)

Two sex pheromone components, 3(Z),6(Z),9(Z)-nonadecatriene (3Z,6Z,9Z-19 H), and 3(Z),6(Z),9(Z)-eicosatriene (3Z,6Z,9Z-20 H), have been positively identified, and a third component, 6(Z),9(Z)-nonadecadiene (6(Z),9(Z)-19 H) has been tentatively identified from abdominal tip extracts of female spring cankerworm moths,Paleacrita vernata Peck (Lepidoptera Geometridae). The pheromone components were identified by a combination of gas chromatography, electroantennography, mass spectrometry, chemical tests, comparison with standards, and field testing. Only 3Z,6Z,9Z-20 H exhibited significant attractant activity when tested alone, and it was potentiated by the other two components. The attractive blend was an 821 ratio of 3Z,6Z,9Z-20H/3Z,6Z,9Z-19H/6Z,9Z-19H. However, the two-component blend of 3Z,6Z,9Z-20 H and 6Z,9Z-19 H (81 ratio) was as attractive as the three-component blend in further field tests. A series of related compounds, the diene monoepoxides available from epoxidation of C₁₉ and C₂₀ 3Z,6Z,9Z-trienes, some of which have been found in the pheromone blends of other moth species, were tested as behavioral antagonists. The attraction of male moths to synthetic lures was suppressed by the addition of 6Z,9Z-cis-3,4-epoxy-nonadecadiene to the lures. Additional experiments were performed to determine the effects of lure dosage, trap height, and trap design on the numbers of male moths captured.Issued as NRCC 30711.     

Temporal patterns of sex pheromone titers and release rates inHolomelina lamae (Lepidoptera: Arctiidae)

Six hydrocarbon components (2-methylhexadecane,n-heptadecane, 2-methylheptadecane, 2-methyloctadecane,n-nonadecane, and 2-methylnonadecane) were identified in sex-pheromone gland extracts and in airborne collections ofHolomelina lamae. Low variability in the ratio of components among individuals indicates tight regulation of blend composition. Minor changes were evident in the quantity and ratio of the blend as a function of time of day. Based on gland extracts, the total quantity of the six components increased from day 1 (X = 6299 ng) to day 4 (X = 7498 ng) and subsequently decreased. No significant correlations were found between total gland contents and wet or dry weights of moths. Emission rates ofH. lamae females were determined from pheromone adsorbed onto Porapak Q. Quantities released peaked shortly after the onset of calling and decreased rapidly as calling continued. Peak release rates ranged from 13 to 350 ng/10 min, and from 37 to 835 ng/60 min. Noncalling females did not emit detectable quantities of pheromone. Based on release rates and the rate of pulsation of the abdominal tip, the average amount released per pulse is not constant. The mean ratio of components released (0.787.45 84.802.842.591.53) was not very different from the ratio of components in gland extracts of 2-day-old females (0.704.1990.12 1.651.911.42). We propose that the blend is atomized rather than volatilized from the gland, thus retaining nearly the same ratios in the female's effluvium as in her gland.     

Components of female sex pheromone of spotted bollworm,Earias vittella F. (Lepidoptera: Noctuidae): Identification and field evaluation in Pakistan

Ovipositor washings from virgin femaleEarias vittella (F.) (Lepidoptera: Noctuidae) moths were examined by gas chromatography (GC) linked to electroantennography (EAG). Six components were detected by the male moth. These were identified by comparison of their retention times with those of a range of synthetic standards on fused silica capillary GC columns as hexadecanal, (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, octadecanal, (Z)-11-octadecenal, and (E,E)-10,12-hexadecadien-1-ol in 1210241 ratio. Field testing in Pakistan showed that a 2102 mixture of (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, and (Z)-11-octadecenal was as attractive to maleE. vittella moths as the six-component mixture and equal in attractiveness to a virgin female moth. Omitting (Z)-11-hexadecenal or (Z)-11-octadecenal greatly reduced this attractiveness. It was found that synthetic lures must be protected from sunlight to prevent loss of attractiveness caused by isomerization of the conjugated diene aldehyde, and addition of (E,Z)-10,12-hexadecadienal, one of the products of isomerization, was shown to reduce attractiveness significantly. During this work, a 101 mixture of (E,E)-10, 12-hexadecadienal and (Z)-11-hexadecenal was shown to be as attractive toE. insulana (Boisd.) male moths as a virgin female moth, and the attractiveness of this mixture was further increased by addition of (E,Z)-10,12-hexadecadienal.     

Sex pheromone of aPlanotortrix excessana sibling species and reinvestigation of related species

The sex pheromone of aPlanotortrix excessana sibling species was investigated. Females were found to produce eight potential pheromone components: dodecyl acetate, tetradecyl acetate (14OAc). (Z)-5-tetradecenyl acetate (Z5-14OAc), (Z)-7-tetradecenyl acetate (Z7-14OAc), (Z)-9-tetradecenyl acetate, hexadecyl acetate, (Z)-7-hexadecenyl acetate, and (Z)-9-hexadecenyl acetate. When these compounds were bioassayed using field-trapping and wind-tunnel techniques, only 14OAc,Z5-14OAc, andZ7-14OAc were found to be behaviorally active. The sex pheromone glands of females of other species including,Planotortrix MBS,Planotortrix M,P. notophaea, Ctenopseustis servana, and aC. obliquana sibling species, were also found to containZ5-14OAc orZ7-14OAc, singly or in combination. In the case ofPlanotortrix M, the addition ofZ7-14OAc to the previously identified sex pheromone blend ofZ5-14OAc and 14OAc was found to increase trap captures of male moths of this species. Thus in these New Zealand species (and in some Australian species),Z5-14OAc andZ7-14OAc appear to be utilized in combination in pheromonal communication just as (Z)-11-tetradecenyl acetate and (E)-11-tetradecenyl acetate are used by many species of Holarctic Tortricidae in the tribe Archipini.Lepidoptera: Tortricidae: Tortricinae.     

Sex pheromone chemistry of the western spruce budwormChoristoneura occidentalis Free

SCOT capillary Chromatographic and SCOT capillary chromatographic-mass spectrometic analyses of gland washes and effluvia of virgin femaleChoristoneura occidentalis Free, have been conducted with both a diapausing and nondiapausing strain of this insect. The following compounds were identified in gland washes and effluvia in both strains:E andZ11–14Ald,E andZ11–14Ac,E andZ11–14OH and 14Ald, 14Ac, and 14OH. The average aldehyde: acetate: alcohol ratio found by analysis of single glands by virgin females (nondiapausing strain) was 170.73. Analysis of virgin female effluvia gave this ratio as 1038 (diapausing strain: %Z=8, 11, 15, respectively) and 1036 (nondiapausing strain: %Z=8, 11, 12, respectively). The saturated components were generally 1–2% of theE isomer in each case. Comparisons of EAG responses of bothC. occidentalis andC. fumiferana toE11–14Ald,E11–14Ac andE11–14OH were made. Correlations with both laboratory and field data previously published were also made betweenC. fumiferana andC. occidentalis.Lepidoptera: Tortricidae.