Effect of formulations and dispensers on attractiveness of virelure to the tobacco budworm

Formulations of virelure, the synthetic sex pheromone of the tobacco budworm,Heliothis virescens (F.), were developed, bioassayed in traps in field cages, and used in traps to survey populations in plant hosts. Virelure (10 mg) laminated between thin sheets of vinyl polymer plastic was attractive to male moths for 21 days, and attractiveness did not regress appreciably for the first 7 days. Another dispenser was an 8 × 30-mm cigarette filter encased in a glass shell vial. A mixture of 10 l (Z)-11-hexadecenal and 0.5 l (Z)-9-tetradecenal, the pheromone components, formulated with wheat germ oil andd-alpha tocopherol (91) in 0.5 ml CH₂Cl₂ (WGOE) was still attractive to males after 5 days. Cottonseed oil, polyethylene glycol 600 distearate (peg-600-d), and peg-6000-d also inhibited excessive vaporization and oxidation of virelure. Virelure (21.25 l) formulated on filters with WGOE and used as bait (replaced weekly) in survey traps caught 27,263 males in 1975; analysis of catches each day for 7-day periods showed that most males were caught within 3 days after baiting, and attractiveness regressed considerably during the last 3–4 days of each week. Four ratios of virelure components were tested as bait (20 mg) in saucer-type pheromone traps, and the 161 ratio caught significantly more male moths than ratios of 241, 321, or 401.Lepidoptera Noctuidae.In cooperation with the Texas Agricultural Experiment Station, Texas A & M University, College Station 77843.This paper reports the results of research only. Mention of a pesticide in this paper does not constitute a recommendation for use by the USDA nor does it imply registration under FIFRA as amended. Also, mention of a commercial or a proprietary product in this paper does not constitute an endorsement by the USDA.     

Behavioral responses of male turnip moths,Agrotis segetum,to sex pheromone in a flight tunnel and in the field

The response of individual male turnip mothsAgrotis segetum was observed in a sustained flight tunnel to a mixture of decyl acetate, (Z)-5-decenyl acetate, (Z)-7-dodecenyl acetate, and (Z)-9-tetradecenyl acetate in proportions similar to those found in gland extracts from virgin females (0.6: 1:5:2.5). Lures containing 3–30 g (Z)-5-decenyl acetate proved to be maximally attractive, with approximately 60% of the males completing all behavioral steps from activation to copulation efforts. A 300-g dosage caused significant arrestment of upwind flight. Peak response to synthetics, however, was significantly lower than to female glands. Omitting decyl acetate from the blend did not affect the activity, while omission of any of the three monounsaturated acetates caused a dramatic decrease in response. In the field maximum trap catches were achieved with 1- to 30-g lures. The subtractive assay carried out in the field confirmed the neutrality of decyl acetate and the importance of the three monoenes. Adding 1% of (Z)-8-dodecenyl acetate (earlier reported as an inhibitor) to the four-component mixture decreased the trap catch to about 50%, and increasing the amount of (Z)-8-dodecenyl acetate to 27% decreased the activity further to about 10%. (Z)-8-Dodecenyl acetate also decreased the number of successful flights in the flight tunnel.Schiff., Lepidoptera: Noctuidae.This study was made within the Swedish project Odour Signals for Control of Pest Insects.     

Identification of sex pheromone components of darksided cutworm,Euxoa messoria,and modification of sex attractant blend for adult males

Eleven pheromone-like compounds were identified in excised abdomen tip extracts of calling adult females of darksided cutworm,Euxoa messoria (Harris). The essential pheromone components were (Z)-7- and (Z)-11-hexadecenyl acetates in a ratio of 140, which agreed with an attractant blend developed empirically by field testing the attractancies of synthetic blends. The pheromone component, (Z)-11-hexadecenol, improved the attraction of darksided cutworm males whereas the components (Z)-9-tetradecenyl acetate and (Z)-7-dodecenyl acetate inhibited their attraction. The other pheromone-like compounds identified in the female extracts had no obvious effect on the attraction of darksided cutworm males. Three compounds that functioned as parapheromones when substituted for (Z)-7-hexadecenyl acetate in the two-component blend were (Z)-7-pentadecenyl, (Z)-7-tetradecenyl, and (Z)-7-tridecenyl acetates. (Z)-11-hexadecenal was not detected in the female extracts, but it had a synergistic effect on the attraction of darksided cutworm moths and inhibited the attraction of male moths of a nontarget species,Helotropha reniformis (Grote). As a trap bait for monitoring purposes, we recommend a four-component blend of (Z)-7-hexadecenyl acetate, (Z)-11-hexadecenyl acetate, (Z)-11-hexadecenol, and (Z)-11-hexadecenal at 12.5, 500, 1, and 10 g/red rubber septum dispenser containing 5 g of antioxidant 2,6-tert-butyl-4-methyl phenol. This blend is effective under field conditions for at least six weeks.     

(Z)-9-tetradecen-1-ol acetate

(Z)-9-Tetradecen-1-ol acetate [(Z)-9-TDA], identified originally as the sex pheromone of the fall armyworm,Spodoptera frugiperda (J.E. Smith), acted as a secondary sex pheromone when it was tested in sticky traps in field tests. Low-level synergism was obtained when 2 and 10% quantities of (Z)-9-TDA were added to 100 g of (Z)-9-dodecen-1-ol acetate, which is now considered the primary sex pheromone.Lepidoptera: Noctuidae.In cooperation with the University of Georgia College of Agriculture Experiment Stations, Coastal Plain Station, Tifton, Georgia 31794.Mention of a proprietary product does not constitute endorsement by the USDA.     

Onion fly trap catch as affected by release rates ofn-dipropyl disulfide from polyethylene enclosures

n-Dipropyl disulfide loadings of at least 1 l and 10 l in polyethylene enclosures were required to effect significant trap catches of onion fly,Hylemya antiqua (Meigen), females and males, respectively. Corresponding release rates for this threshold for trap catch were ca. 100 g/hr. Catches increased with loadings up to 100 l/capsule but then plateaued. As determined gravimetrically, the release rate from enclosures containing a reservoir of chemical remained constant under isothermal conditions but increased exponentially as a function of temperature.Diptera: AnthomyiidaePaper No. 9422 of the Michigan State University Agricultural Experiment Station. Received for publication April 29, 1980.     

Synergistic Sex Pheromone Components of White-Spotted Tussock Moth, Orgyia thyellina

In 1996, the exotic white-spotted tussock moth (WSTM), Orgyia thyellina (Lepidoptera: Lymantriidae), was discovered in Auckland, New Zealand. Because establishment of WSTM would threaten New Zealand's orchard industry and international trade, eradication of WSTM with microbial insecticide was initiated. To monitor and complement eradication of WSTM by capture of male moths in pheromone-baited traps, pheromone components of female WSTM needed to be identified. Coupled gas chromatographic–electroantennographic detection analysis of pheromone gland extract revealed several compounds that elicited responses from male moth antennae. Mass spectra of the two most EAD-active compounds suggested, and comparative GC-MS of authentic standards confirmed, that they were (Z)-6-heneicosen-11-one (Z6–11-one) and (Z)-6-heneicosen-9-one, the latter termed here thyellinone. In field experiments in Japan, Z6–11-one plus thyellinone at a 100:5 ratio attracted WSTM males, whereas either ketone alone failed to attract a single male moth. Addition of further candidate pheromone components did not enhance attractiveness of the binary blend. Through the 1997–1998 summer, 45,000 commercial trap lures baited with 2000 g of Z6–11-one and 100 g of thyellinone were deployed in Auckland towards eradication of the residual WSTM population.Dedicated to my dear mother in honor of her 75th birthday     

Biological activity of synthetic hydrocarbon mixtures of cuticular components of the female housefly (Musca domestica L.)

Mixtures of (Z)-9-alkenes (C₂₁-C₃₃),n-alkanes (C₂₁-C₃₃), and mono- and dimethylalkanes (C₂₇, C₂₉), as components of the cuticular lipids washed from the female housefly (Musca domestica L.), were synthesized and assayed for their biological activity on male houseflies. The (Z)-9-alkenes and their hydrogenatedn-alkanes were synthesized from jojoba wax components by the appropriate chain elongation. The methylalkanes were prepared by Grignard coupling reaction of the appropriate alkyl halides, catalyzed by Li₂CuCl₄. Six- to 7-day-old virgin male houseflies exhibited the highest mating strike activity toward 6- to 7-day-old virgin females. The mating strike activity of the synthetic hydrocarbons was studied by exposing 6- to 7-day old virgin males to petrol-ether-rinsed 1 to 2-day-old dead females treated with these chemicals. (Z)-9-Tricosene was the most active hydrocarbon tested when it was applied in amounts of 10 g to a washed dead female. Amounts of 5 g of (Z)-9-tricosene did not cause sexual activity in the males. Mixture of (Z)-9-alkenes showed low activity when applied at 10-g amounts. However, when mixtures were made of 5 g of (Z)-9-tricosene with 5 fig of each of certain mixtures of (Z)-9-alkenes, the striking activity became as high as that of 10 g of (Z)-9-tricosene. This might be a synergism effect. The mixtures ofn-alkanes, as well as the mono- and dimethylalkanes, showed moderate activity. When (Z)-9-tricosene was added to these materials no increase in male activity was observed.     

Ovipositional response of tobacco budworm moths (Lepidoptera: Noctuidae) to cuticular labdanes and sucrose esters from the green leaves ofNicotiana glutinosa L. (Solanaceae)

Field plots of three accessions ofNicotiana glutinosa L. (Nicotiana species accessions 24, 24A, and 24B) at Oxford, North Carolina and Tifton, Georgia were heavily damaged by natural populations of tobacco budworms,Heliothis virescens (F.), during 1985–1989. Experiments in outdoor screen cages demonstrated that all accessions ofN. glutinosa were as prone to oviposition byH. virescens moths as was NC 2326, a commercial cultivar of flue-cured tobacco,N. tabacum L. However, in greenhouse experiments, tobacco budworm larvae did not survive or grow as well when placed on plants ofN. glutinosa as they did when placed on plants of NC 2326. Four labdane diterpenes (manool, 2-hydroxymanool, a mixture of sclareols, and labda-13-ene-8,15-diol [labdenediol]) and two sucrose ester fractions (2,3,4-tri-O-acyl-3-O-acetyl-sucrose [G-SE-I] and 2,3,4,-tri-O-acyl-sucrose [G-SE-II]) were isolated from green leaves of the three accessions ofN. glutinosa. These components were bioassayed for their effects on the ovipositional behavior of tobacco budworm moths using small screen cages in a greenhouse at Oxford, North Carolina. Labdenediol, manool, and both sucrose ester fractions stimulated tobacco budworm moths to oviposit on a tobacco budworm-resistant Tobacco Introduction, TI 1112 (PI 124166), when these materials were sprayed onto a leaf.This article reports the results of research only. Mention of a proprietary product does not constitute endorsement or recommendation for its use by USDA, ARS, or by the North Carolina Agricultural Research Service.     

Sugar beet crown borer,Hulstia undulatella (Clemens) 1: Identification and field tests of female sex pheromone gland components

Electroantennogram profiles of saturated and monounsaturated 12-, 14-, and 16-carbon acetates, and 12- and 14-carbon alcohols implicated (Z)-9-tetradecen-1-ol acetate (Z9-14: Ac) as a component of the female sex pheromone ofHulstia undulatella (Clemens). Gas chromatography-mass spectrometric analysis of extract of the female sex pheromone glands showed the presence of Z9-14:Ac (8.5 ng/female), (Z)-9-tetradecen-1-ol (Z9-14:OH), and (Z)-11-hexadecen-1-ol acetate (Z11-16:Ac) in a ratio of 100421, respectively. In tests in sugar beet fields, Z9-14:Ac alone produced some trap catch. Addition of Z9-14: OH did not increase catch while addition of Z11-16:Ac eliminated catch, but addition of both Z9-14:OH and Z11-16: Ac increased catch sevenfold. A combination of Z9-14: OH and Z11-16: Ac without Z9-14: Ac did not produce trap catch. A lure of 200 g Z9-14:Ac+16 g Z9-14:OH+42 g Z11-16:Ac is suggested for use in monitoring traps.Lepidoptera: Pyralidae: Phycitinae.     

Female sex pheromone of iris borer,Macronoctua onusta (Lepidoptera: Noctuidae)

Chromatographic and mass spectrometry studies of heptane extracts of the ovipositors of the iris borer,Macronoctua onusta, showed that the females produce several compounds that are the same as those produced by females of the tobacco budworm,Heliothis virescens. In trapping experiments, a mixture of (Z)-11-hexadecenal, (Z)-11-hexadecen-1-ol, and (Z)-9-tetradecenal (9442) proved to be the minimum set of compounds required to cause effective capture of iris borer males in the field.     

Sex pheromone of blackheaded fireworm,Rhopobota naevana (Lepidoptera: Tortricidae), a pest of cranberry

Splitless capillary gas chromatography indicated the presence of (Z)- and (E)-11-tetradecenyl acetate and (Z)-11-tetradecenyl alcohol in the washes of female abdominal tips of the blackheaded fireworm,Rhopobota naevana (Hubner). Gas chromatography combined with mass spectroscopy confirmed the presence of tetradecenyl acetate in extracts of female tips. The low levels observed in these extracts (< 1 ng/female equivalent), prevented further chemical and spectroscopic identification. These materials were found to be stimulatory at low levels in electroantennogram studies. A combination of 9 g of (Z)-11-tetradecenyl acetate and 3 g of (Z)-11-tetradecenyl alcohol on rubber septa in wing traps provided an effective attractant. (Z)-9-Dodecenyl acetate, a previously reported attractant, did not significantly increase field trapping catches when added to the binary mixture, but was found to enhance trap catches when added to each of the primary components.     

Reinvestigation confirms action of Δ11-desaturases in spruce budworm moth sex pheromone biosynthesis

The biosynthesis of a large number of sex pheromone components of various moth species has been shown to start with common fatty acids and involve chain shortening by two carbons and introduction of a double bond at the 11–12 position. A recent report indicates that one of these common components, (E)-11-tetradecenyl acetate, is present in the eastern spruce budworm,Choristoneurafumiferana, but is not made by this pathway. Reinvestigation of this insect using in vivo and in vitro techniques indicates that the acetate indeed is made by a sequence of reactions similar to that used in other leafroller moths. In fact, evidence was found for the presence of several 11-desaturase systems in spruce budworm. One produced a large quantity of (Z)-11-hexadecanoic acid, and another produced (E)-11-tetradecanoic acid. It is not known if the small amount of (Z)-11-tetradecanoic acid is produced by either of those two systems or by a third system. A comparison with other species showed that cabbage looper moths have only the first system, redbanded leafroller moths use the last two systems, and European corn borer moths have all three.     

Electrophysiological and behavioral responses of female Helicoverpa armigera to compounds identified in flowers of African marigold, Tagetes erecta

Seven electrophysiologically active compounds were detected in air-entrained headspace samples of live flowers of Tagetes erectaanalyzed by gas chromatography (GC) linked to a female Helicoverpa armigeraelectroantennograph (EAG) using polar and nonpolar capillary columns. These compounds were subsequently identified using GC linked to mass spectrometry as benzaldehyde, (S)-(–)-limonene, (R,S)-(±)-linalool, (E)-myroxide, (Z)--ocimene, phenylacetaldehyde, and (R)-(–)-piperitone. Electrophysiological activity was confirmed by EAG with a 1-g dose of each compound on filter paper eliciting EAG responses that were significantly greater than the solvent control response from female moths. Wind-tunnel bioassays with T. erectaheadspace samples, equivalent to 0.4 flower/hr emission from a live flower, elicited a significant increase in the number of upwind approaches from female H. armigerarelative to a solvent control. Similarly, a seven-component synthetic blend of EAG-active compounds identified from T. erectapresented in the same ratio (1.0 : 1.6 : 0.7 : 1.4 : 0.4 : 5.0 : 2.7, respectively) and concentration (7.2 g) as found in the natural sample elicited a significant increase in the number of upwind approaches relative to a solvent control during a 12-min bioassay that was equivalent to that elicited by the natural T. erectafloral volatiles.     

Looplure efficacy and electrophysiological responses in three plusiinae species

Source concentration differences of (Z)-7-dodecen-1-ol acetate, or looplure, were evaluated for field trapping efficiency and electrophysiological responses with malePseudoplusia includens (Walker),Trichoplusia ni (Hubner) andRachiplusia ou (Guenné) (Lepidoptera: Noctuidae). Sticky traps baited with 1000 g of the lure captured a significantly greater (P < 0.05) number of maleP. includens andT. ni than any other concentration;R. ou males were caught at a greater rate in traps baited with 100 g of looplure, significantly more (P < 0.05) than with 1000 g. Electroantennogram (EAG) studies demonstrated that antennae of maleP. includens have a lower response threshold to looplure than eitherT. ni orR. ou antennae, the latter demonstrating the highest significant threshold of response. No differences in the stimulus-response functions of the three species were detected.Lepidoptera: Noctuidae.     

Sex pheromone chemistry of the female tobacco budworm moth,Heliothis virescens

(Z)-11 -Hexadecenal (77–91%), (Z)-7-hexadecenal (0.1–2%), (Z)-9-hexadecenal (0.3–2%), hexadecanal (3–19%), (Z)-11-hexadecen-1-ol (1–5%), tetradecanal (1–3%), and (Z)-9-tetradecenal (1–3%) were identified from the heptane washes of the ovipositor of femaleHeliothis virescens (F.) females. In field bioassays, a 152-g mixture of these seven compounds deployed in an insect trap exceeded the attractiveness of 4 virgin femaleH. virescens for males and was 5–6 times more attractive than a mixture of (Z)-1 1-hexadecenal and (Z)-9-tetradecenal (virelure) that was previously reported as the sex pheromone of the species. Four of the seven compounds produced byH. virescens females are also produced byH. zea (Boddie). Specificity of pheromonal signals among the two species is ostensibly dependent upon one or more of the three additional compounds [tetradecanal, (Z)-9-tetradecenal, and (Z)-1 1-hexadecen-1-ol] produced by femaleH. virescens.     

Sex pheromone of the black cutworm moth,Agrotis ipsilon

(Z)-7-Dodecen-1-yl acetate (I) and (Z)-9-tetradecen-1-yl acetate (II) have been identified as sex pheromone components of the black cutworm moth,Agrotis ipsilon (Hufnagel). They are emitted by the female in approximately a 51 ratio. Differential saturation studies with male antennae suggest that there are two different acceptor sites for the two pheromone components. The most effective lures found in field trapping tests were 30 g of I plus 10 g of II on a rubber septum, and a 31 mixture of I and II dispensed from a 0.2-mm-ID glass capillary tube sealed at one end.Lepidoptera: Noctuidae.Supported at Geneva, in part by the Rockefeller Foundation and by National Science Foundation Grant GB-38020; and at Wooster, in part by Environmental Protection Agency Grant EPA R802547 and by USDA Cooperative State Research Service Grant 316-15-99. Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal Paper3186. Approved for publication as Journal Article113-78 of the Ohio Agricultural Research and Development Center, Wooster, OH 44691.     

Identification and synthesis of insect pheromone XXX. Sex pheromone of mulberry clearwing mothParadoxecia pieli Lieu

(E,Z)-3,13-OctadecadienyI acetate (1a) and (E,Z)-3,13-octadecadien-1-ol(2a) were identified from the sex pheromone gland of the virgin female mulberry clearwing mothParadoxecia pieli L., by GC analysis, EAG, SCR survey, and field bioassay. One female equivalent contained 250 ng of1a and 30 ng of2a. In the field tests, 100g of synthetic1a was attractive to male moths of the species.Identification and Synthesis of Insect Pheromone XXIX. Sex Pheromone of the Vine Tree BorerParathrene Regalis B. Guo Guang-zhong, Liu Han-quan, Lin Guo-qiang, Wu Cai-hong, Meng Lian-zhong,Organic Chemistry (CH.), 504, 1990.     

Sex pheromone of femaleMyelois cribrella Hübner (Lepidoptera: Pyralidae)

Females ofMyelois cribrella contain about 20 ng/gland of the primary sex pheromone components (Z)-9-tetradecenyl acetate, (9Z,12E)-9,12-tetradecadienyl acetate, and (Z)-11-hexadecenyl acetate in proportions of 4115, respectively. These physiologically active components are accompanied by a number of related compounds such as (Z)-9-tetradecen-1-ol, hexadecyl acetate, (9Z,12E)-9,12-tetradecadien-1-ol, (Z)-11-hexadecen-1-ol, octadecyl acetate, octadecan-1-ol, and eicosyl and docosyl acetates. Octadecyl acetate, the most abundant component, represents about 42 ng/female moth; however, no physiological activity could be attributed to it. In field tests, a trap baited with a 1-mg mixture of (Z)-9-tetradecenyl acetate, (9Z,12E)-9,12-tetradecadienyl acetate, and (Z)-11-hexadecenyl acetate in a ratio of 121 caught more male moths than three live female moths.Pheromones, 58. Pheromones, 57: Bestmann et al. (1987).     

Novel Antifeedant and Insecticidal Compounds from Avocado Idioblast Cell Oil

Several insecticidal compounds have been identified by bioassaydriven fractionation of avocado, Persea americana Mill, idioblast cell oil. A flash chromatography fraction of the oil showed substantial toxicity to early instars of the generalist insect herbivore, Spodoptera exigua (Hübner) (100% mortality after seven days). Following further fractionation, five biologically active compounds, 2-(pentadecyl)furan, 2-(heptadecyl)furan, 2-(1E-pentadecenyl)furan, 2-(8Z,11Z-heptadecadienyl)furan, and the triglyceride triolein, were identified. Several minor components were also tentatively identified, including 2-(1Z-pentadecenyl)furan, 2-(1E-heptadecenyl)furan, and 2-(1E,8Z,11Z-heptadecatrienyl)furan. Several 2-alkylfurans of this type have been reported previously from avocado (Persea spp.) and have received the common name of avocadofurans. The major compounds were tested individually for toxic and growth inhibitory effects. Individually, the compounds had low to moderate toxicity. Of these, 2-(pentadecyl)furan had the greatest effects, with an LC₅₀ value of 1031 g/g. At concentrations of 600 g/g or higher in diets, larval growth was inhibited by >70% compared to controls. The analogous 2-(heptadecyl)furan had an LC₅₀ value of 1206 g/g, and also significantly reduced larval growth (>75% versus controls) at concentrations of >600 g/g. The unsaturated analogs 2-(1E-pentadecenyl)furan and 2-(8Z, 11Z-heptadecadienyl)furan were less toxic. Triolein was only weakly toxic, with an LC₅₀ value of 10,364 g/g diet. Larval growth was inhibited only at concentrations of 7000 g/g or higher. The potential of avocadofurans in insect control is discussed.     

Identification of sex pheromone components of jack pine budworm,Choristoneura pinus pinus freeman

Chemical identification and field-trapping experiments have shown that a blend of 8515 (E,Z)-11-tetradecenyl acetates and 8515 (E,Z)-11-tetradecen-1-ols (in a 91 ratio) are female sex pheromone components for jack pine budworm,Choristoneura pinus pinus. This blend of chemicals, formulated in PVC (0.1 %, w/w) sources is as effective a trap bait as virgin females. Preliminary wind tunnel observations have indicated that this blend, effective as a trap bait, is not equivalent to females.Lepidoptera: Tortricidae.