Orientation of flying male Anobium punctatum (Coleoptera: Anobiidae) to sex pheromone: separating effects of visual stimuli and physical barriers to wind

Abstract. Flying male woodworm, Anobium punctatum , are able to locate a source of female pheromone offered as a point source but land more quickly if the same odour source is presented on a model 'tree' (cylinder). We tested the response to a two-dimensional black 'tree' marked as a silhouette on the upwind screen of the wind tunnel, with or without a hidden upwind barrier to the wind. The beetles responded equally to pheromone presented on a visual silhouette with wind barrier and to the hidden upwind wind-barrier alone, suggesting that the wind-barrier itself has a significant effect on insect orientation and landing: visual stimuli do not add to the landing response if the barrier is present. However, without the barrier upwind, landing was faster when the visual stimulus was present than without. This is the third forest-living species to be shown to respond in this way, which suggests this phenomenon may be more widespread. The possibility that this phenomenon is present in other, non-forest, phytophagous insects, their predators and parasitoids is discussed.     

Responses of Mamestra suasa male moths to synthetic pheromone compounds in a wind tunnel

The upwind flight and landing responses of male Mamestra suasa (Den. & Schiff.) (Lepidoptera; Noctuidae) to various synthetic chemicals were studied in a wind tunnel. A mixture of (Z)-11-hexadecenyl acetate (Z11-16: Ac) and (Z)-11-hexadecenal (Z11-16: Ald) elicited upwind flight responses past the midpoint of the wind tunnel, and both components were necessary for landing of the males to occur at the pheromone source point. The best response to the mixtures tested was to a ratio 100:1 (ng) of Z11-16: Ac and Z11-16: Ald (blend B).The addition of (Z)-9-tetradecenyl acetate (Z9-14: Ac) (10 ng) to blend B resulted in a significant decrease of upwind flight and landing responses. The inhibitory effect of this chemical when it is mixed with blend B, and the presence of a specific receptor for this compound in sensilla trichodea of male M. suasa, suggest that Z9-14: Ac is involved in the chemical communication between M. suasa and other sympatric species. The addition of (Z)-11-hexadecenol (Z11-16: OH) (1 or 10 ng) to blend B had no effect on male upwind flight and landing responses. This compound does not seem to be involved in the chemical communication of this species.

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Résumé L'observation et la comptabilisation des vols orientés et des atterrissages des mâles de Mamestra suasa (Den. & Schiff.) (Lepidoptera; Noctuidae) sur une source de phéromone de synthèse ont mis en évidence un mélange attractif appelé mélange B et constitué par 100 ng de Z11-16: Ac et 1 ng de Z11-16: Ald. L'attraction et l'atterrissage sont sous la dépendance du mélange de ces 2 composés. Les variations de leurs proportions relatives affectent les différentes phases du comportement de vol des mâles.L'addition de 10 ng d'acétoxy-1 tetradécène-9 Z (Z9-14: Ac) diminue significativement les proportions de vols orientés et d'atterrissages par rapport aux réponses obtenues avec le mélange B seul. L'effet inhibiteur de cette molécule sur l'attractivité du mélange B et la présence chez M. suasa d'un récepteur spécialisé dans la perception de ce composé suggèrent que le Z9-14: Ac est impliqué dans la communication chimique entre M. suasa et d'autres espèces sympatriques. L'addition d'hexadécènol-11 Z (Z11-16: OH) au mélange B à la dose de 1 ou 10 ng ne modifie pas les réponses des mâles. Ce composé ne semble pas impliqué dans la communication chimique chez M. suasa.

     

甜菜夜蛾对性信息素的行为反应及其田间诱捕效果

人工合成的甜菜夜蛾性信息素两组分（顺,反）-9,12-十四碳二烯醇醋酸酯（Z9,E12-14：Ac）和（顺）-9-十四碳烯醇（Z9-14：OH）按不同配比制成诱芯,在风洞中均能引起雄蛾搜索气迹、定向飞行及接近诱芯的行为反应.不同配比和剂量的诱芯诱虫效果差异显著（p＜0.05）.Z9,E12-14：Ac和Z9-14：OH按7：3配比,诱虫活性最高,表现在风洞中,搜索气迹、定向飞行和接近诱芯的蛾数最高,与处女蛾的引诱效果相当.以此配比制成的性诱剂在田间诱捕的虫量最多,与风洞的试验结果基本一致.诱芯剂量在0.05～0.5mg范围内均有显著的诱虫效果,但剂量过低或过高均导致诱捕率下降.同一配比诱芯在风洞中引起雄蛾接近诱芯的蛾量与田间诱蛾量呈显著相关（R1=0.968,R2=0.961）.并对这些结果在甜菜夜蛾田间性诱剂防治应用的前景进行了讨论.     

Responses of male Helicoverpa zea to single pulses of sex pheromone and behavioural antagonist

Male Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) flying in a pheromone plume respond to the loss of pheromone when they fly into a large pocket of clean air by going into crosswind casting flight in a mean of 0.48 s; 0.62 s after re‐contacting pheromone presented as a single pulse, they surge upwind in a kind of narrow zigzagging flight. After 0.36 s of surging, they lapse into casting flight once again in the clean air following the pulse. The addition of a known behavioural antagonist (Z)‐11‐hexadecenyl acetate (Z11–16:Ac), to the pheromone significantly increases the mean latency of the response to a single pulse to 0.85 s. No other aspects of the surge were significantly changed by the presence of antagonist in the single pulse of pheromone. Thus, unlike males of the related species, Heliothis virescens, which show significant changes in track and course angles when antagonist is present in single pulses, only an increased latency of response to a filament containing antagonist occurred in H. zea males. The increased latency could act cumulatively when the male is exposed rapidly and repeatedly to filaments in a natural plume and explain the profound arrestment effect of the antagonist in such plumes. The latencies to casting and surging in response to a pulse of pheromone blend are longer than those of the smaller species, H. virescens, and may be due to size‐related differences in manoeuverability of H. zea vs. H. virescens.     

斜纹夜蛾在风洞中对性信息素的行为反应及田间诱捕试验

雌蛾腺体内含量最高的组份9,11-14∶Ac（A）在风洞中能引起雄蛾从搜索气迹、定向飞行到撒开味刷企图交尾连续的行为反应,而雌蛾腺体内其它组份单独使用时均不能引起雄蛾上述行为反应。一定量的Z9,E12-14∶Ac（B）对A的活性有增效作用,诱芯中B数量过多,不但失去对A的活性增效作用,还对雄蛾接近诱芯和企图交尾有强烈的抑制作用。9-14∶Ac（C）与11-14∶Ac (D)对雄蛾的定向行为无影响,诱芯中含有50%的C时,反而对雄蛾接近诱芯和企图交尾有抑制作用。A与B在滤纸诱芯中的含量比例与诱芯释放的挥发物比例明显不同,从9∶1（A∶B）诱芯释放的挥发物比例更接近于雌蛾腺体内的天然比例。田间诱捕试验中两组份诱芯的诱捕量随两组份比例不同而变化, 9∶1（A∶B）诱芯的诱捕量最大,1∶1（A∶B）诱芯的诱捕量低于单一的A组份诱芯。     

Scoliopteryx libatrix (L.) (Lep., Noctuidae) male reaction to the synthetic main sex pheromone component and its isomers – wind tunnel and field investigations

Abstract: The four stereoisomers of 6,13-methylheneicosene were tested with Scoliopteryx libatrix (L.) males in a wind tunnel. The most active isomer was (Z6,S13)-methylheneicosene which had been identified as the main sex pheromone component of the species. Some medium activity was found for (Z6,R13)- and (E6,S13)-, while the (E6,R13)-stereoisomer showed the lowest activity. These results were confirmed in field tests with sticky traps. Monitoring of S. libatrix at two sites showed that the flight of the insects started at the end of March to the beginning of April and lasted till August to the beginning of September. It was concluded that the males of the second generation were not attracted by the pheromone.     

Behavioral responses of maleHeliothis armigera (Lepidoptera: Noctuidae) moths in a flight tunnel to combinations of components identified from female sex pheromone glands

Six compounds were identified from gland extracts of the cotton bollworm, Heliothis armigera(Hubner): (Z)-11-hexadecenal (Z11-16:Ald), (Z)-9-hexa-decenal (Z9-16:Ald), hexadecanal, (Z)-11-hexadecenol (Z11-16:OH), (Z)-7-hexadecenal (Z7-16:Ald), and (Z)-9-tetradecenal (Z9-14:Ald). Each of the compounds that were identified was examined for its ability to elicit sexual responses from male moths in a flight tunnel. Males flew upwind to Z11-16:Ald alone, but greater levels of copulatory responses were evoked with the addition of 2.5% Z9-16:Ald to the Z11-16:Ald. Addition of hexadecanal to the binary mixture had no effect in raising the behavioral response of the males in the flight tunnel. The effect of Z7-16:Ald on male flight depended on the loading. The addition of 1% of this component to 2 mg of the binary mixture reduced levels of copulatory response, but the same addition (1 %) to 10 g of the binary mixture increased copulatory response. The addition of 79-14:Ald or Z11-16:OH to the binary mixture reduced behavioral responses of males. High loadings of the binary mixture (200–2000 g) were better than a low loading (10 g) in eliciting response of males.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 2455-E, 1988 series.     

Behavioral Responses of Adult Deathwatch Beetles,Xestobium rufovillosum de Geer (Coleoptera: Anobiidae), to Light and Dark

Video tracking equipment was used to quantify the behavior of adult deathwatch beetles, Xestobium rufovillosum in a light/dark choice chamber. Effects of insect age, sex, and mating status on this behavior were analysed. The behavior recorded included the initial direction of movement, the time taken to reach the light or dark zone, the time spent in each zone, the time spent moving in each zone and the distance moved in each zone. The results show that both male and female insects 1–12 days old prefer the light zone. Insects more than 12 days old demonstrate sexually differential photoresponsive behavior. Males show a preference for the light. Females show an increasing preference for the dark, mated females more so than unmated females. The implications of these differences in behavior are discussed in relation to control programmes.     

Cowpea weevil flights to a point source of female sex pheromone: analyses of flight tracks at three wind speeds

Abstract.  Two-day-old male cowpea weevils, Callosobruchus maculatus, fly upwind to a point source of female sex pheromone at three wind speeds. All beetles initiating flight along the pheromone plume make contact with the pheromone source. Analysis of digitized flight tracks indicates that C. maculatus males respond similarly to moths tested at several wind speeds. Beetles' mean net upwind speeds and speeds along their track are similar ( P  > 0.05) across wind speeds, whereas airspeeds increase ( P <  0.01) with increasing wind speed. Beetles adjust their course angles to fly more directly upwind in higher wind speeds, whereas track angles are almost identical at each wind speed. The zigzag flight paths are generally narrow compared with most moth flight tracks and interturn distances are similar ( P  > 0.05) at the wind speeds employed. The frequency of these counterturns across the wind line is almost constant regardless of wind speed, and there is little variation between individuals. The upwind flight tracks are more directly upwind than those typically seen for male moths flying upwind toward sex pheromone sources. Male moths typically produce a bimodal distribution of track angles to the left and right of the windline, whereas C. maculatus males' track angles are centred about 0°. Preliminary examination of two other beetle species indicates that they fly upwind in a similar fashion.     

枣镰翅小卷蛾雄蛾对性信息素的行为反应

在风洞中观察了枣镰翅小卷蛾Ancylis sativa雄蛾对合成性信息素不同组分(E9-12∶Ac和Z9-12∶Ac)的行为反应。E9-12∶Ac组分能够引起少量雄蛾(8-3%)完成从兴奋到接触诱芯并呈现交配企图的全部行为反应,而雄蛾对Z9-12∶Ac组分无反应。E9-12∶Ac+Z9-12∶Ac混合物中前者占60%～65%效果最好,能使71.7%～76.7%雄蛾到达诱芯并呈现交配企图。E9-12∶Ac与Z9-12∶Ac为6.5∶3.5时,200 ng～2 000 ng的剂量效果最好,有76.7%～81.7%雄蛾到达诱芯。     

Hickory shuckworm Cydia caryana: electroantennogram and flight tunnel studies of potential sex pheromone components

Electroantennogram (EAG) measurement of male Cydia caryana moth antennal olfactory response to monounsaturated 12 and 14 carbon alcohols and acetates indicated that the (E)-8-, (E)-10- conjugated double bond system of a dodecadien-1-ol acetate is a critical chemical structural component of the C. caryana sex pheromone. Additionally, EAG measurements implicated (E)-8-dodecen-1-ol acetate, (Z)-8-dodecen-1-ol acetate, (Z)-9-dodecen-1-ol acetate and (Z)-12-tetradecen-1-ol as potential minor pheromonal components. An EAG dosage-response study suggested that there were at least two heterologous populations of pheromone acceptors. Behavioral analysis of male moth response in a flight tunnel to compounds which evoked the stronger EAG responses suggested that (E,E)-8,10-dodecadien-1-ol acetate and (Z)-9-dodecen-1-ol acetate resemble or are C. caryana sex pheromonal components, while (Z)-8-dodecen-1-ol acetate and (E)-10-dodecen-1-ol acetate are either parapheromones or are minor pheromone components. Behavioral significance of (Z)-12-tetradecen-1-ol was difficult to interpret in the flight tunnel.

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Résumé Les réponses olfactives antennaires de Cydia caryana, mesurées par électroantennogrammes (EAG), aux alcools et acétates à carbones monounsaturés en positions 12 et 14, ont montré que le système conjugué de double liaison, (E)-8-, (E)-10- du dodecadien-1-ol acétate constitue un composé chimique strutural critique de la phéromone sexuelle de C. caryana.De plus, les acétates: (E)-8-dodecen-1-ol,(Z)-8-dodecen-1-ol,(Z)-9-dodecen-1-ol, et le (Z)-12-tetradecen-1-ol, se sont révélés en AEG comme des composés secondaires de la phéromone. L'étude par AEG de la relation dose-réponse a conduit à l'hypothèse de deux catégories de populations de récepteurs de phéromones. L'analyse comportementale des résponses des papillons mâles dans le tunnel de vol aux composés qui ont provoqués les plus forts AEG, on fait estimer que les acétates (E,E)-8,10-dodécadien-1-ol et (Z)-9-dodecen-1-ol ressemblent (ou sont) les constituants de la phéromone sexuelle de C. caryana; tandis que les (Z)-8-dodecen-1-ol et (E)-10-dodecen-1-ol sont, soit des paraphéromones, soit des constituants mineurs de la phéromone.La signification biologique du (Z)-12-tétradécen-1-ol a été difficile à interprêter avec les expériences en tunnel de vol.

     

Disruption of male spruce budworm orientation to female moths by pheromone and pheromone analogues in a wind tunnel

Abstract. The ability of male spruce budworm moths, Choristoneura fumiferana (Clem.), to orientate to and locate virgin female moths was investigated in a laboratory wind tunnel. When presented with two caged ‘target female’ moths, more than 99% of the male moths locked on and flew directly to the females. When confined for 3 h before release, downwind of a three-dimensional array of thirty-five evenly distributed female moths (a density of 40/m³), over 90% of the males still successfully oriented to one or another of the females, although not always to the target females. With an array of thirty-five septa containing either E-11-tetradecenyl acetate on E-11-tetradecenol there was no visible change in behaviour; >90% of the males flew directly to the two target females, which indicates that neither the acetate nor the alcohol has potential for mating disruption. An array of thirty-five septa containing a 955 blend of E- and Z-11-tetradecenal, the main components of the spruce budworm sex pheromone, significantly reduced the numbers of male moths able to locate the target females, and effects were concentration-dependent. The highest concentration, which gave a release rate similar to that of a calling female, produced the same level of disruption as the thirty-five females, but sensory fatigue became a factor in addition to ‘false trail following’. Lower concentrations were significantly less effective, with no evidence of sensory fatigue. At all concentrations significant numbers of males flew to the septa (false trail following), but when male moths were left uncaged in the tunnel for a further 3h, most eventually located the females. This suggests that false trail following alone will not prevent mating. The level of disruption was not improved by the addition of 2% tetradecanal to the 955 blend. Similar levels of disruption to the 955 blend were obtained with an 80:20 blend. A 5050 blend still caused a significant amount of false trail following, but less than the other blends. The ability of male spruce budworm to orientate to off-blend trails was enhanced if the males were first exposed to the natural, female-produced pheromone.     

田间二化螟雄蛾对不同配比性信息素的嗅觉反应 及性信息素识别相关基因表达水平差异

【目的】本研究旨在从行为和嗅觉分子水平探究二化螟Chilo suppressalis雄蛾对性信息素嗅觉反应的地理种群差异及其机理,以明确该害虫田间种群雄成虫的嗅觉适应性及其特点。【方法】采用7种Z11-16∶Ald, Z9-16∶Ald和Z13-18∶Ald配比不同的三元性信息素诱芯(Z11-16∶Ald和Z9-16∶Ald配比分别为540 μg∶540 μg, 864 μg∶216 μg, 945 μg∶135 μg, 980 μg∶98 μg, 1 003 μg∶77 μg, 1 016 μg∶64 μg和1 045 μg∶35 μg,而Z13-18∶Ald含量保持不变),在中国6省水稻田间诱捕二化螟雄成虫;利用实验室风洞测定864 μg∶216 μg, 980 μg∶98 μg和1 016 μg∶64 μg配比诱芯在田间诱捕的越冬代和第2代二化螟雄蛾分别对这3个配比的性信息素诱芯的行为反应;并采用RT-qPCR方法测定这7种性信息素配比不同的诱芯诱捕的雄蛾触角中二化螟雄蛾12个性信息素识别相关基因的表达水平。【结果】在田间试验中,Z11-16∶Ald和Z9-16∶Ald不同配比的性信息素诱芯对水稻二化螟雄蛾均有引诱作用,但不同配比引诱的二化螟雄蛾占比不同。6省诱芯中Z11-16∶Ald和Z9-16∶Ald的最佳配比不同,并且同一配比性信息素诱芯在不同省份引诱的二化螟雄蛾占比也不同。结果表明,不仅在不同地区诱芯的性信息素最佳配比不同,而且在不同地区不同配比性信息素的诱蛾量占比也不同。实验室风洞试验中,864 μg∶216 μg和1 016 μg∶64 μg配比诱芯田间诱捕雄蛾分别对864 μg∶216 μg和1 016 μg∶64 μg配比诱芯的行为反应均显著强于对其余两种配比诱芯,980 μg∶98 μg配比诱芯田间诱捕雄蛾对1 016 μg∶64 μg, 980 μg∶98 μg和864 μg∶216 μg配比诱芯的行为反应无显著差异。在RT-qPCR测定中,除GOBP1外,其余11个性信息素识别相关基因在Z11-16∶Ald和Z9-16∶Ald不同配比诱芯诱捕雄蛾触角中的表达水平均存在显著差异,其中PBP3, PBP4, PR1, PR2, PR4, PR5和PR6 7个基因的表达水平与性信息素配比之间存在显著的线性相关。【结论】本研究明确了中国二化螟不同地理种群性信息素嗅觉差异,不仅有助于提高该害虫的性诱防控效率,而且也有助于理解其嗅觉地理种群差异的成因。     

Factors influencing response of flying Prostephanus truncatus to its male-produced aggregation pheromone

Abstract. The effects of age, sex, mating status, pre-exposure to pheromone, resource (diet) quality, and starvation on the response of Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) to its male-produced aggregation pheromone were investigated.Age was an important factor determining the level of response to pheromone: young adults were more responsive than older adults.The suitability of the resource in which P.truncatus is present affected its dispersal tendency, but not its sensitivity to pheromone per se. Sex, mating status, brief prior exposure to pheromone, and starvation did not influence the response of the larger grain borer to pheromone.The orientation behaviour of the beetle is described, and it is proposed that the pheromone primarily functions as a 'suitable resource location and colonization signal'.     

异色瓢虫对蚜虫性外激素的行为反应研究

蚜虫性外激素假荆芥内酯(Z,E-Nepetalactone,NEP)能够吸引多种捕食性和寄生性天敌昆虫,它专一性强,生物活性突出,对非靶标生物安全。异色瓢虫Harmonia axyridis(Pallas)作为一种重要的捕食性天敌,被广泛应用于农业生产中。为明确异色瓢虫对蚜虫性外激素的行为反应,本研究在室内用"Y"型嗅觉仪测定了异色瓢虫成虫对不同剂量NEP的嗅觉行为反应;并在田间,每7 d释放100μL浓度为1 mg/m L的NEP,测定了NEP对异色瓢虫种群数量变动的影响。室内嗅觉测定试验结果表明异色瓢虫雌虫对10μL剂量NEP有显著的选择性,而雄虫对1μL剂量NEP有显著的选择性;田间试验发现,释放NEP的处理区异色瓢虫数量显著高于对照区。本研究为蚜虫性外激素在害虫绿色防控中的应用提供了依据。     

榆木蠹蛾雄蛾对性信息素不同组分及其不同比例和剂量混合物的风洞行为反应

【目的】本研究旨在深入了解榆木蠹蛾Holcocerus vicarius(Walker)信息素通讯系统。【方法】在风洞中观察了榆木蠹蛾雄蛾对合成性信息素不同组分及其不同比例及剂量混合物的行为反应。【结果】单组分试验结果表明,仅有Z7-14:Ac能够引起少量雄蛾完成从兴奋到接触诱芯并出现预交尾的全部行为反应,其余4个单组分(E3-14:Ac,Z3E5-14:Ac,E3-14:OH和Z3-14:OH)只能引起雄蛾兴奋,均不能引起雄蛾向性信息素源定向飞行。二元混合物(Z7-14:Ac+E3-14:Ac)明显增加雄蛾完整的性行为反应比例,三元混合物(Z7-14:Ac+E3-14:Ac+Z3E5-14:Ac)比例为10∶4∶4,剂量为1 300μg时有71.7%雄蛾发生预交尾,剂量为1 000μg时有70.3%雄蛾发生预交尾,两者差异不显著(P0.05)。【结论】榆木蠹蛾风洞行为实验为进一步研究其性信息素相关生物学特性及应用性信息素对榆木蠹蛾进行综合防治奠定了基础。     

MaleHeliothis virescens maintain upwind flight in response to experimentally pulsed filaments of their sex pheromone (Lepidoptera: Noctuidae)

Aspects of the intermittent fine structure of an odor plume were mimicked and experimentally modified in the wind tunnel using an air-pulsing device. Filaments of a behaviorally active blend of six sex-pheromone components created by the device in a temporally regular fashion elicited sustained upwind flight and source location in male Heliothis virescens.Males did not exhibit sustained upwind flight in significant numbers until a frequency of 4 filaments/s was delivered, at a loading of 1 g of the major component, Z11-16: Ald, with the other components loaded at their appropriate ratios. A loading of 10 g Z11-16: Ald was found to be optimal at this filament delivery rate. Electroantennogram recordings to different filament delivery rates of the complete blend indicated that a stationary male antenna can respond to the pulse rates used in this study. Importantly, when a main component necessary for upwind flight, Z9-14:Ald, was isolated into its own filaments and pulsed alternately against filaments of the five other components (including the other component essential for upwind flight, Z11-16: Ald), upwind flight to the source was significantly reduced (9%) compared to upwind flight and source location in response to filaments composed of the entire blend (30%), indicating that the complete pheromone blend must arrive on the antenna simultaneously for optimal evocation of sustained upwind progress. Neurophysiological evidence from other studies suggests that higher-order interneurons whose phasic response is enhanced when the entire blend is presented simultaneously may be of importance in explaining this behavioral difference stemming from synchronous vsasynchronous arrival of the components.     

Evidence for a mounting sex pheromone in the brown ear tick Rhipicephalus appendiculatus,Neuman 1901 (Acari: Ixodidae)

The presence of a mounting sex pheromone was demonstrated on the surface of fed female Rhipicephalus appendiculatus. This pheromone, which is present on the female cuticle, allows the male to recognise the female. The pheromone was removed by cleaning the female in hexane, resulting in the loss of male mating behaviour in in vitro experiments. Male mating behaviour was resumed when extract made from fed female cuticle was replaced on cleaned females. When the extract was transferred to innanimate objects typical male mating behaviour was released. Preliminary chemical analyses indicated that the active component of the extract was contained in the sterol ester fraction of the extract.