Comparison of female attractiveness and male response among populations of Choristoneura rosaceana (Harris) in western and eastern U.S. apple orchards

Female obliquebanded leafrollers, Choristoneura rosaceana (Harris), collected from Oregon, Michigan, and New York were deployed in delta traps in Michigan apple orchards to compare their relative attractiveness to Michigan males of the same species. Females originating from Oregon attracted more males than females originating from New York during both generations of leafroller flight in Michigan. Also, females from Oregon attracted more males in Michigan than did "native" Michigan females during the first generation of flight. Analysis of gland extracts from the three populations revealed significantly more of each pheromone component in females originating from Oregon (approximately nine-fold more pheromone per female overall) than those from Michigan. However, there were no significant differences in the relative amounts of each pheromone component between Oregon and Michigan females. A 100:4:5:2 blend of Z11-14:OAc, E11-14:OAc, Z11-14:OH, and Z11-14:Ald was optimal for catching males in Michigan with no added or detrimental effect of Z11-14:Ald, confirming previous studies. However, 100:1 ratios of Z11-14:OAc relative to either E11-14:OAc or Z11-14:OH (also containing 2% Z11-14:Ald) captured more males in Oregon apple orchards compared with 100:4 and 100:10 ratios of Z11-14:OAc relative to either E11-14:OAc or Z11-14:OH. Addition of increasing amounts of Z11-14:Ald relative to Z11-14:OAc (range, 0-8:100) into a blend also containing 4% E11-14:OAc and 5% Z11-14:OH increased male catch in Oregon but not in Michigan. Our results suggest that pheromone blend quantity rather than blend quality may explain greater attractiveness of western compared with eastern female C. rosaceana to males in Michigan. Also, an optimized generic blend for monitoring male C. rosaceana across North America should contain Z11-14:Ald as has been previously shown, but should not exceed 4:100 ratios of both E11-14:OAc and Z11-14:OH relative to Z11-14:OAc for optimized catch of males in the western United States.     

黄杨绢野螟雌蛾性信息素的鉴定及诱蛾活性

【目的】研究旨在深入探讨中国黄杨绢野Diaphania perspectalis 的雌蛾性信息素组成及诱蛾活性。【方法】利用气质联用仪（GC-MS）对黄杨绢野螟正常型性成熟雌蛾的性腺体提取物和合成标样比较分析,并用反-11-十六碳烯醛(E11-16:Ald) 、顺-11-十六碳烯醛（Z-11-16:Ald）、顺-9-十六碳烯醛（Z-9-16:Ald)、顺-11-十六碳烯醇（Z-11-16:OH)等物质进行触角的电生理测定,最后开展田间诱集比较试验以筛选出最佳性信息素混合物。【结果】Z-11-16:Ald为中国黄杨绢野螟正常型性信息素主要组分,E-11-16:Ald的含量极低,Z-11-16:OH未检测到。正常型雄性黄杨绢野螟触角对Z-11-16:Ald, E-11-16:Ald, Z-9-16:Ald和Z-11-16:OH产生强烈的EAG反应,并随着浓度的提高而显著增加;而对Z-11-16:Ac和E-11-16:Ac的嗅觉反应较弱,低于对植物绿叶气味顺3-己烯乙酸酯（Z-3-6:Ac）的反应。单一Z-1-16:Ald对正常型雄性黄杨绢野螟具有强烈的诱集效果,加入E-11-16:Ald有一定的增效作用,但在统计上则不显著。单一Z-11-16:Ald组分对黑化型雄性黄杨绢野螟无引诱活性,必需加入一定比例的E-11-16:Ald才显示诱蛾活性。Z-11-16:Ald:E-11-16:Ald的比例为250 μg:250 μg时诱集到的黑化型雄性黄杨绢野螟数量最多,而Z-11-16:Ald:E-11-16:Ald的比例为429 μg:71 μg时则诱集到的正常型雄性黄杨绢野螟数量最多。同时,单一Z-11-16:Ald也可引诱大量雄性粘虫Mythimna separata,但E-11-16:Ald抑制其活性。【结论】中国黄杨绢野螟的性信息素主成分是Z-11-16:Ald,单一组分即可在田间强烈引诱雄蛾,E-11-16:Ald的功能只起到微弱的增效作用,但也可能起种的专一性的作用。正常型与黑化型黄杨绢野螟对性信息素的嗅觉反应存在差异,黑化型黄杨绢野螟的性信息素接近日本种,即性信息素组成为Z-11-16:Ald和E-11-16:Ald 的混合物,其比例为1:1,且E-11-16:Ald为必需。     

Sex pheromone analysis and effective attraction of males of the cabbage webworm,Hellula undalis,inhabiting the Mekong Delta of Vietnam

Hellula undalis is a harmful insect pest of green mustard in the Mekong Delta of Vietnam. In order to establish a tool for a sustainable pest control program, the sex pheromone of H. undalis inhabiting the Mekong Delta was examined. GC-EAD and GC–MS analyses of pheromone gland extracts from the virgin females elucidated three new components, (Z)-11-tetradecenyl acetate (Z11-14:OAc), (Z)-11-hexadecenal (Z11-16:Ald), and (11E,13E)-11,13-hexadecadien-1-ol, in addition to the known pheromone component (11E,13E)-11,13-hexadecadienal (E11,E13-16:Ald). Double bond positions of the two monoenyl components were determined by GC–MS analysis of the pheromone extract treated with dimethyl disulfide. On the other hand, GC–MS analysis of the female body extract detected the unsaturated hydrocarbon (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H). Field examinations of their synthetic compounds indicated the significant role of E11,E13-16:Ald as a major component and a clear synergistic effect of the two monoenyl compounds as a minor component. Although the 3:3:7 mixture of Z11-14:OAc, E11-16:Ald, and E11,E13-16:Ald captured the largest number of males among the tested mixtures, the activity was still quite a bit lower than that of virgin females. However, the 3:3:7:1 mixture, which was prepared by adding a small amount of Z3,Z6,Z9-23:H to the 3:3:7 ternary lure, succeeded in attracting males more powerfully than the females did. This strong synergistic effect was not observed when the triene was added to unmixed E11,E13-16:Ald, indicating important roles of not only the triene but also the two monoenyl compounds as natural pheromone components.     

Reidentification of the female sex pheromone of the Indian meal moth, Plodia interpunctella: evidence for a four-component pheromone blend

Pheromone gland extracts from calling female Plodia interpunctella contained at least seven compounds that consistently elicited electroantennographic responses from male antennae upon gas chromatographic analysis. Three of these compounds were found to be the previously identified gland constituents, i.e., (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:OAc), (Z,E)-9,12-tetradecadienal (Z9,E12-14:Ald) and (Z,E)-9,12-tetradecadienol (Z9,E12-14:OH). A fourth EAD-active compound was identified as (Z)-9-tetradecenyl acetate (Z9-14:OAc). The homologue (Z)-11-hexadecenyl acetate (Z11-16:OAc) was also identified in the extracts, but showed no EAD activity. The identity of all five compounds was confirmed by comparison of GC retention times and mass spectra with those of synthetic standards. In flight tunnel tests there were no significant differences in response of male P. interpunctella to the bait containing all four EAD-active compounds and the responses to female gland extacts. A behavioural assay of different two-compound blends in the flight tunnel showed that only addition of the corresponding aldehyde to the major pheromone component Z9,E12-14:OAc raised the male response. A subtractive assay, however, revealed that the exclusion of any of the compounds from the complete four-compound blend reduced its activity significantly. We thus conclude that the female-produced sex pheromone of P. interpunctella consists of at least four components, i.e., Z9,E12-14:OAc, Z9,E12-14:Ald, Z9,E12-14:OH and Z9-14:OAc.In a field trapping test performed in a storage facility, the four-component blend attracted significantly more males of P. interpunctella than traps baited with Z9,E12-14:OAc alone. In contrast, the highest number of Ephestia kuehniella males was found in the traps baited with this major component, suggesting that the secondary pheromone components contribute to the species specificity of the blend.     

Helicoverpa zea males (Lepidoptera: Noctuidae) respond to the intermittent fine structure of their sex pheromone plume and an antagonist in a flight tunnel

Abstract. We investigated the behavioural response of male Helicoverpa zea (Boddie) to the fine-scale structure of an odour plume experimentally modified in a wind tunnel by using an air-pulsing device. Male H. zea flew upwind to pulsed filaments of a binary pheromone blend of (Z)-11-hexadecanal (Z11-16:Ald) and (Z)-9-hexadecanal (Z9-16:Ald) in the ratio of 20:1. Sustained upwind flight in experimentally altered intermittent plumes was dependent on concentration, as well as the frequency of generation of odour filaments. At a loading of 10μg of the major pheromone component, Zll-16:Ald, which gave an emission rate of approximately that released by a female H. zea , sustained upwind flight and source contact correlated positively with filament delivery rate, becoming significant at a minimum filament delivery rate of 2/s. Decreases in upwind progress and source location were recorded at a loading of 1 μg of Z11-16:Ald. At this suboptimal dosage, a high filament generation rate of 10/s was necessary for significant upwind progress and source contact. When an interspecific compound: (Z)-11-hexadecenyl acetate (Z11-16:OAc), was added to the attractive pheromone binary aldehyde blend of H. zea at a proportion of 10% of the major pheromone component, and pulsed from the same source, there was a significant reduction in sustained upwind progress and source location by males, indicating that Z11-16:OAc is antagonistic to the upwind progress of H. zea. However, Z11-16:OAc was less antagonistic when its filaments were isolated and alternated with pheromone filaments, indicating a strong effect of the synchronous arrival of odour filaments on the antenna needed for antagonism of upwind flight.     

Sex pheromone of the butterbur borer, Ostrinia zaguliaevi

The sex pheromone blend of the butterbur borer, Ostrinia zaguliaevi (Lepidoptera: Pyralidae) was analyzed by means of gas chromatography-electroantennographic detection (GC-EAD), GC-mass spectrometry and a series of wind-tunnel bioassays. Four EAD-active compounds were detected in the female sex pheromone gland extract, and these were identified as tetradecyl acetate (14:OAc), (Z)-9-tetradecenyl acetate (Z9-14:OAc), (E)-11-tetradecenyl acetate (E11-14:OAc) and (Z)-11-tetradecenyl acetate (Z11-14:OAc). The average amounts ± s.d. of the four compounds in a single sex pheromone gland were 7.9±3.7 ng, 10.1±3.2 ng, 1.1±0.5 ng and 11.6±5.1 ng, respectively. In a wind-tunnel bioassay, the ternary blend of Z9-, E11- and Z11-14:OAc at a ratio found in the sex pheromone gland (45:5:50) elicited the same behavioral responses from the males as did virgin females and pheromone gland extract. Removal of any single compound from the ternary blend significantly diminished the pheromonal activity, whereas addition of 14:OAc to the ternary blend had no effect on the males' behavioral responses. Therefore, it was concluded that the sex pheromone blend of O. zaguliaevi is composed of Z9-14:OAc, E11-14:OAc and Z11-14:OAc at a ratio of 45:5:50.     

烟青虫(Helicoverpa assulta Guenée)信息素的结构鉴定及田间试验(英语)

北京地区的烟青虫(Helicover Pa asslta Cucn(?)e)的性信息素腺体提取物经毛细管柱气相色谱分析及GC MS分析,鉴定了6种组分.这6种组分为:十六醛(16:Ald)、顺 9—十六烯醛(Z9—16:Ald)、顺11—十六烯醛(Zll 16:Ald)、顺9—十六烯醇(Z9-16:OH)、顺11—十六烯醇(Zll-16:OH)、顺9—十六烯基乙酸酯(Z9 16:OAc),比例为10.9:58.7:3.9:14.7:1.1:10.7.田间试验表明,只有16:Ald、Z9 16:Ald和Zll 16:Ald(比例为15.3:79.2:5.5)组成的三组分诱芯和Z9—16:Ald和Zll—16:Ald(比例为93.4:6.6)组成的两组分诱芯对于雄蛾有强烈的引诱活性.在3种醛为组分的诱芯中加入Z9 16:OH明显地降低引诱活性.     

Evidence of olfactory antagonistic imposition as a facilitator of evolutionary shifts in pheromone blend usage in Ostrinia spp. (Lepidoptera: Crambidae)

Olfactory receptor neuron (ORN) response was measured to assess why some males ("rare males") of the Asian corn borer (ACB), Ostrinia furnacalis, have a broad behavioral response to fly upwind to both the ACB and the European corn borer (ECB), Ostrinia nubilalis, pheromone blends. We performed single-sensillum electrophysiological recordings on ACB males that had been behaviorally assessed for upwind flight response to the ACB blend [60:40 (Z)-12-tetradecenyl acetate (Z12-14:OAc) to (E)-12-tetradecenyl acetate (E12-14:OAc)], as well as to ECB (Z-strain) and ECB (E-strain) blends [3:97 and 99:1 (Z)-11-tetradecenyl acetate (Z11-14:OAc) to (E)-11-tetradecenyl acetate (E11-14:OAc)]. Sensilla from all types of males had large- and small-spike-sized ORNs responding strongly to Z12- or E12-14:OAc, but weakly to Z11- and E11-14:OAc. In the majority of males ("normal males") that flew upwind only to the ACB blend, Z11-14:OAc elicited responses in an intermediate spike-sized ORN associated with behavioral antagonism that is mainly tuned to (Z)-9-tetradecenyl acetate (Z9-14:OAc). In the rare-type ACB males that flew to both the ACB and ECB pheromone blends, Z11-14:OAc did not stimulate this ORN. Increased responsiveness to ancestral pheromone components by ORNs associated with behavioral antagonism could be instrumental in reproductive character displacement, or in reinforcement and reproductive isolation during speciation by helping to increase assortative mating between males and females in derived populations that use novel sex pheromone blends.     

Identification of the Sex Pheromone of the Tree Infesting Cossid Moth Coryphodema tristis (Lepidoptera: Cossidae)

The cossid moth (Coryphodema tristis) has a broad range of native tree hosts in South Africa. The moth recently moved into non-native Eucalyptus plantations in South Africa, on which it now causes significant damage. Here we investigate the chemicals involved in pheromone communication between the sexes of this moth in order to better understand its ecology, and with a view to potentially develop management tools for it. In particular, we characterize female gland extracts and headspace samples through coupled gas chromatography electro-antennographic detection (GC-EAD) and two dimensional gas chromatography mass spectrometry (GCxGC-MS). Tentative identities of the potential pheromone compounds were confirmed by comparing both retention time and mass spectra with authentic standards. Two electrophysiologically active pheromone compounds, tetradecyl acetate (14:OAc) and Z9-tetradecenyl acetate (Z9-14:OAc) were identified from pheromone gland extracts, and an additional compound (Z9-14:OH) from headspace samples. We further determined dose response curves for the identified compounds and six other structurally similar compounds that are common to the order Cossidae. Male antennae showed superior sensitivity toward Z9-14:OAc, Z7-tetradecenyl acetate (Z7-14:OAc), E9-tetradecenyl acetate (E9-14:OAc), Z9-tetradecenol (Z9-14:OH) and Z9-tetradecenal (Z9-14:Ald) when compared to female antennae. While we could show electrophysiological responses to single pheromone compounds, behavioral attraction of males was dependent on the synergistic effect of at least two of these compounds. Signal specificity is shown to be gained through pheromone blends. A field trial showed that a significant number of males were caught only in traps baited with a combination of Z9-14:OAc (circa 95% of the ratio) and Z9-14:OH. Addition of 14:OAc to this mixture also improved the number of males caught, although not significantly. This study represents a major step towards developing a useful attractant to be used in management tools for C. tristis and contributes to the understanding of chemical communication and biology of this group of insects.     

SEX PHEROMONE COMPONENTS OF THE OREIENTAL TOBACCO BUDWORM, HELICOVERPA ASSULTA GUENÉE: IDENTIFICATION AND FIELD TRIALS

Abstract  The sex pheromone gland extracts of the Oriental tobacco budworm, Helicover assulta Guenée, collected from North China in Beijing area, were analyzed by capillary gas chromatograph(GC) and 6 components from the extracts were identified by capillary GC—MS as hexadecanal (16:Ald), (Z)9-hexadecenal (Z9–16:Ald), (Z)-11-hexadecenal (Z11–16:Ald), (Z)-9-hexadecen-1-ol (Z9–16:OH), Z11-hexadecen-1-ol (Z11–16:OH), Z-9-hexadecenylacetate (Z9–16:OAc) at a ratio of 10. 9: 58. 7: 3. 9: 14. 7: 1.1: 10. 7. Field studies indicated that an optimum blend of Z9–16:Ald and Z11–16:Ald was 100: 7. Addition of 16: Ald or Z9–16:Ac to the two aldehyde blend showed no significant effect on attractiveness. However presence of Z9–16:OH in the blends significantly reduced male captures.     

Altered olfactory receptor neuron responsiveness in rare Ostrinia nubilalis males attracted to the O. furnacalis pheromone blend

Three percent of E-strain Ostrinia nubilalis males fly upwind in response to the Ostrinia furnacalis pheromone blend [a 40:60 ratio of (E)-12-tetradecenyl acetate to (Z)-12-tetradecenyl acetate (E12-14:OAc to Z12-14:OAc)], in addition to their own pheromone blend [a 99:1 ratio of (E)-11-tetradecenyl acetate to (Z)-11-tetradecenyl acetate) (E11-14:OAc to Z11-14:OAc)]. We assessed the olfactory receptor neuron (ORN) responses of these behaviorally "rare" males versus those of normal males. For the three ORNs housed within each sensillum, we tested responsiveness to Z12-14:OAc, E12-14:OAc, Z11-14:OAc, E11-14:OAc, and the behavioral antagonist (Z)-9-tetradecenyl acetate (Z9-14:OAc). Z11-14:OAc, E11-14:OAc, and Z9-14:OAc stimulated ORNs exhibiting distinct small, large, and medium spike sizes, respectively. For rare and normal males, both Z12-14:OAc and E12-14:OAc usually elicited responses from the largest-spiking ORN. In many ORNs of normal males, Z12-14:OAc or E12-14:OAc stimulated the smaller-spiking ORN that is responsive to Z11-14:OAc. In rare males, detectable ORN responses from the smaller-spiking ORN in response to Z12- and E12-14:OAc were virtually non-existent. These differences in ORN tuning in rare males will tend to create an ORN firing ratio between the large- and small-spiking ORNs in response to the O. furnacalis blend that is similar to that elicited by the O. nubilalis blend.     

Identification of the sex pheromone of Ostrinia palustralis

By means of gas chromatography with electroantennographic detection, gas chromatography-mass spectrometry and a series of bioassays, (E)-11-tetradecenyl acetate (E11-14:OAc) and (Z)-11-tetradecenyl acetate (Z11-14:OAc) at a ratio of 99:1 were identified as female sex pheromone components of Ostrinia palustralis. The average amounts of E11- 14:OAc and Z11-14:OAc in a single sex pheromone gland were 37.2±24.4 ng and 0.3±0.2 ng, respectively. In a wind-tunnel bioassay, the binary blend of E11- and Z11-14:OAc elicited the same male behavioral responses as did virgin females.     

合成性信息素对柑桔潜叶蛾的田间引诱作用

目前柑桔潜叶蛾的防治主要依赖化学农药, 而且生产中缺少有效测报技术。为此, 我们于2009年6月30日至10月6日在浙江宁波通过有机合成柑桔潜叶蛾Phyllocnistis citrella（鳞翅目, 细蛾科）的3种性信息素化合物顺7, 顺11, 反13-十六碳三烯醛、顺7, 顺11-十六碳二烯醛和顺7-十六碳烯醛, 配制成不同浓度比例的混合物, 进行田间试验比较其引诱活性。结果表明, 单一的顺7, 顺11, 反13-十六碳三烯醛对柑桔潜叶蛾雄蛾就可以显示较强的引诱作用, 而顺7, 顺11-十六碳二烯醛单一成分没有引诱活性, 顺7, 顺11, 反13-十六碳三烯醛与顺7, 顺11-十六碳二烯醛的二元混合物30∶1~3∶1之间活性较强, 而在30∶1的质量比例时诱虫量最高。含顺7-十六碳烯醛的三元混合物, 当顺7, 顺11, 反13-十六碳三烯醛∶顺7, 顺11-十六碳二烯醛∶顺7-十六碳烯醛三者比例为100∶10∶3时有显著增效作用。剂量与诱捕活性试验显示每枚诱芯1 mg顺7, 顺11, 反13-十六碳三烯醛的剂量引诱作用最强, 随浓度降低, 引诱作用下降。诱捕器在0.8~1.5 m之间的不同悬挂高度对诱捕数量无显著影响。结果说明, 顺7, 顺11, 反13-十六碳三烯醛、顺7, 顺11-十六碳二烯醛和顺7-十六碳烯醛组成的三元混合物诱芯可以作为柑桔潜叶蛾的诱杀技术并应用于其生物防治和预测测报。     

Notes on New Zealand mammals 10. Effect of observer position on group size and level of aggression of mating brown hares

Abstract

The sex pheromones of two endemic New Zealand tortricid species were investigated. Females of the first species, Cnephasia jactatana, a pest of kiwifruit, were found to produce (Z)-11-tetradecenyl acetate (Z11-14:OAc) in their sex pheromone gland. When tested in the field, this compound on its own elicited significant catches of male C. jactatana. However, the addition of even very small amounts (0.3%) of the geometric isomer, (E)-11-tetradecenyl acetate (E11-14:OAc), to Z 11-14:OAc virtually suppressed trap catches. The sex pheromone of the second species, Merophyas leucaniana, was found to consist of a mixture of Z11-14:OAc, E11-14:OAc, tetradecyl acetate, and (Z)-11-tetradecenol. This species is morphologically very similar to the congeneric species, M. divulsana, the Australian lucerne leafroller. The sex pheromone of M. leucaniana is also very similar to that of the so-called “Z-type” of M. divulsana, which is now found in New Zealand. The pheromone components of C. jactatana and M. leucaniana are discussed in relation to those found in other tortricids.     

Development of pheromone-based mating disruption for control of the eye-spotted bud moth, Spilonota ocellana

The potential for pheromone-based mating disruption of eye-spotted bud moth (ESBM), Spilonota ocellana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), in apple orchards in the Okanagan Valley of British Columbia was examined in small-plot trials. In a preliminary experiment, treatment of the orchard atmosphere with a 99:1 blend of Z8-tetradecenyl acetate (Z8-14:OAc) and Z8-tetradecenyl alcohol (Z8-14:OH) completely inhibited captures of male ESBM in pheromone-baited traps, but treatment with Z8-14:OAc alone did not. Therefore, all subsequent trials used the two-component blend as a disruptant. Mean catches of male ESBM in traps baited with 0.1, 1, 10, or 20 mg of 99:1 Z8-14:OAc and Z8-14:OH were significantly reduced (81–97%) in pheromone-treated plots relative to similar traps placed in control plots. In both control and treated plots, there was a significant positive relationship between trap bait dose and trap catch. In pheromone-treated plots, this suggests that high doses of trap baits over-ride the camouflage effect of disruption or overcome the effect of sensory adaptation and habituation. The number of virgin-female baited traps capturing at least one male ESBM was reduced by 96%, and mating of virgin females on mating tables was reduced by 95% in plots treated with the two-component pheromone. The total amount of Z8-14:OAc released from pheromone disruption dispensers during the latter field trials was estimated to average 6.4 g ha^-1 over 11 days or 26.4 mg ha^-1 h^-1. The low levels of Z8-14:OH released from disruption dispensers could not be estimated by GC analysis. Dispensers loaded with a 99:1 blend of Z8-14:OAc and Z8-14:OH were highly attractive to males in baited traps, indicating that they have the potential to induce false trail following.     

Trapping effect of synthetic sex pheromone of Acleris fimbriana (Lepidoptera: Tortricidae) in Chinese northern orchard

The yellow tortrix, Acleris fimbriana Merick (Lepidoptera: Tortricidae), is an economically important insect pest on fruit trees with four generations a year in North China. In order to develop a new and effective method for forecasting and controlling the pest, the sex pheromone was studied. We have identified the female sex pheromone as (E)-11,13-tetradecadienal (E11,13-14:Ald), (E)-11,13-tetradecadienyl acetate (E11,13-14:Ac) and (E)-11-tetradecenyl acetate (E11-14:Ac). Trapping effect of synthetic chemicals E11,13-14:Ald, alone and in combination with E11,13-14:Ac or/and E11-14:Ac to A. fimbriana males was tested in Beijing Xishan Orchard (2001). E11,13-14:Ald on its own was much attractive to A. fimbriana males. Neither E11,13-14:Ac nor E11-14:Ac alone caught any moths. The catches markedly increased by adding E11,13-14:Ac to E11,13-14:Ald. The optimum ratio of E11,13-14:Ald and E11,13-14:Ac was 6:4 to 5:5. This attractiveness was apparently enhanced when 5% to 10% of E11-14:Ac was added. The best field activity was in the lure baited with a 6:4:1 ratio of E11,13-14:Ald, E11,13-14:Ac and E11-14:Ac at a dosage of 1000 microg/septum. The effect of antioxidant, 2,6-di-tert-butyl-4-methylphenol [butylated hydroxyluene (BHT)], to the synthetic pheromone blends on its duration and catching efficacy was also tested. Addition of 5-10% BHT to the synthetic pheromone could prolong the life-span of pheromone chemicals for 6-8 weeks, thereby increased its catching efficacy.     

Sex pheromone of Argyrotaenia pomililiana (Lepidoptera: Tortricidae), a leafroller pest of apples in Argentina

Sex pheromone gland extracts of Argyrotaenia pomililiana Trematerra & Brown females contained seven 14-chain compounds, the Z and E isomers of 11-tetradecenyl acetate, 11-tetradecen-1-ol, and 11-tetradecenal, respectively, together with tetradecyl acetate. In field trapping tests, a 100:5 blend of Z11-14:Ac and Z11-14:Al was shown to be suitable for detection and monitoring of A. pomililiana. This species-specific lure will facilitate the use of mating disruption against codling moth, Cydia pomonella (L.), in Argentine fruit orchards.     

Pheromone-mediated mating disruption of Choristoneura rosaceana: is the most attractive blend really the most effective?

An attractive four-component pheromone blend containing a major component Z11-tetradecenyl acetate, and three minor components, E11-tetradecenyl acetate, Z11-tetradecenyl alcohol, and Z11-tetradecenyl aldehyde was tested as a mating disruptant against western Canadian populations of the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), in organic apple orchards in British Columbia. Efficacy of this four-component blend was compared to that of partial pheromone blends containing the major component plus one or two minor components. A trapping experiment confirmed that, Conrel® fibre disruption dispensers containing the four-component blend were more attractive than disruption dispensers containing the two- or three-component partial blends. A small-plot protocol was followed to compare atmospheric treatments with these blends as mating disruptants at a release rate of 10 mg ha–1 h–1 and from 1000 dispensers ha–1. Mechanisms of mating disruption, such as false-trail following and camouflage of pheromone plumes, that may be evoked to a greater degree by an attractive blend, did not appear to augment the effectiveness of mechanisms invoked by the less attractive blends, as the proportion of mating among tethered females was equal in plots treated with these blends and was reduced by 85–90% compared to the nontreated control. When the four-component pheromone blend was tested at different release rates, mating disruption in small plots began to break down at a release rate of 1.3 mg ha–1 h–1 using a dispenser density of 1000 ha–1. Above 1.3 mg ha–1 h–1 there was no dose response in release rates tested and at release rates below this dose the proportion of tethered females mating was the same as in the nontreated control. The four-component pheromone blend was tested against, and found to be no more effective than, the two-component partial blend at the threshold release rate of 1.3 mg ha–1 h–1 when it was released from 1000 or 250 disruption dispensers. Our results suggest that disruption mechanisms evoked by the attractive blend did not enhance the mating disruption effect provided by the simple blend, therefore a two-component blend may be useful in an operational mating disruption program for C. rosaceana.     

Sustained-flight tunnel responses of male lightbrown apple moth to synthetic sex pheromone

ABSTRACT. The upwind flight response of individual male lightbrown apple moths, Epiphyas postvittana (Walker), to twenty combinations of the two pheromone components, (E)-11-tetradecenyl acetate (E11-14:OAc) and (E,E)-9,11-tetradecadienyl acetate (E,E-9,11–14:OAc), was observed in a sustained-flight tunnel. At the lowest dosage of E11-14:OAc tested (3 μg), a significantly greater percentage of males flew upwind to and landed at a source emitting 10% E1,E-9, 11–14:OAc than to all other sources. As the source dosage was increased, males showed decreased specificity of upwind flight to ratios of the two components. However, at the highest dosage of E11-14:OAc tested (300 μg), the response specificity of males shifted to blends containing lower percentages of E,E-9,11–14:OAc. The addition of tetradecyl acetate to a blend of the two components did not result in any detectable increase in male response. Analyses of the pheromone glands of individual female Iightbrown apple moths showed that females produced a range of ratios of E11-14;OAc:E,E-9,11–14:OAc from 100:2.2 to 100:11.4 with a median of approximately 100:7, reasonably paralleling the peak response of males. Pre-exposure of males to a blend of the two components, followed by exposure to E11-14:OAc alone (previously reported as a 'memory' effect) resulted in no significant response to E11-14:OAc alone.