Reduced Mating Success of Female Tortricid Moths Following Intense Pheromone Auto-Exposure Varies with Sophistication of Mating System

Mating disruption is a valuable tool for the management of pest lepidopteran species in many agricultural crops. Many studies have addressed the effect of female pheromone on the ability of males to find calling females but, so far, fewer have addressed the effect of pheromone on the mating behavior of females. We hypothesized that mating of female moth species may be adversely affected following sex pheromone auto-exposure, due to abnormal behavioral activity and/or antennal sensitivity. Our results indicate that, for Grapholita molesta and Pandemis pyrusana females, copulation, but not calling, was reduced following pre-exposure to sex pheromone. In contrast, for Cydia pomonella and Choristoneura rosaceana, sex pheromone pre-exposure did not affect either calling or copulation propensity. Adaptation of female moth antennae to their own sex pheromone, following sex pheromone auto-exposure, as measured by electroantennograms, occurred in a species for which identical exposure reduced mating success (G. molesta) and in a species for which such exposure did not affect mating success (C. rosaceana). These results suggest that pre-exposure of female moths of certain species to sex pheromone may further contribute to the success of pheromone-based mating disruption. Therefore, we conclude that, in some species, mating disruption may include a secondary mechanism that affects the mating behavior of female moths, in addition to that of males.     

Sex Pheromone of South American Tortricid Moth Argyrotaenia sphaleropa

By means of electroantennographic detection and gas chromatography-mass spectrometry, the sex pheromone of Argyrotaenia sphaleropa was identified as a mixture of (Z)-11-tetradecenal, (Z)-11,13-tetradecadienal, (Z)-11-tetradecenyl acetate, and (Z)-11,13-tetradecadienyl acetate in the ratio of 1:4:10:40. Best trap catches were obtained with mixtures of (Z)-11-tetradecenal and (Z)-11,13-tetradecadienal in the ratio of 1:4 to 1:9.     

新烟碱类杀虫剂在华专利分析

从专利申请类别、技术生命周期、专利申请人3个方面分析研究了新烟碱类杀虫剂在华专利发展现状,预测了其发展趋势。     

Interspecific Pheromone Plume Interference Among Sympatric Heliothine Moths: A Wind Tunnel Test Using Live, Calling Females

Three species of North American heliothine moths were used to determine the level at which interspecific female interference of male attraction to conspecific females occurs. We used live calling females of Heliothis virescens, H. subflexa, and Helicoverpa zea, as lures for conspecific males in a wind tunnel, and then placed heterospecific females on either side of the original species such that the plumes of the three females overlapped downwind. In nearly all combinations, in the presence of heterospecific females, fewer males flew upwind and contacted or courted the source than when only conspecific females were used in the same spatial arrangement. Males did not initiate upwind flight to solely heterospecific female arrangements. Our results show that the naturally emitted pheromone plumes from heterospecific females of these three species can interfere with the ability of females to attract conspecific males when multiple females are in close proximity. However, the fact that some males still located their calling, conspecific females attests to the ability of these male moths to discriminate point source odors by processing the conflicting information from interleaved strands of attractive and antagonistic odor filaments on a split-second basis.     

新烟碱类杀虫剂呋虫胺的合成新工艺

在调研国内外有关呋虫胺研究文献的基础上,通过反复实验,找到了合成呋虫胺的新工艺.。以1,4-丁内酯计总收率达到36%。通过正交试验对各步骤反应进行了优化,确定了最佳反应条件。相比其它方法,本工艺合成呋虫胺具有成本低、步骤少、三废少、规模化生产可行性高等优点。     

Attractiveness of a Four-component Pheromone Blend to Male Navel Orangeworm Moths

The attractiveness to male navel orangeworm moth, Amyelois transitella, of various combinations of a four-component pheromone blend was measured in wind-tunnel bioassays. Upwind flight along the pheromone plume and landing on the odor source required the simultaneous presence of two components, (11Z,13Z)-hexadecadienal and (3Z,6Z,9Z,12Z,15Z)-tricosapentaene, and the addition of either (11Z,13Z)-hexadecadien-1-ol or (11Z,13E)-hexadecadien-1-ol. A mixture of all four components produced the highest levels of rapid source location and source contact. In wind-tunnel assays, males did not seem to distinguish among a wide range of ratios of any of the three components added to (11Z,13Z)-hexadecadienal. Dosages of 10 and 100 ng of the 4-component blend produced higher levels of source location than dosages of 1 and 1,000 ng.     

The Dynamics of Pheromone Gland Synthesis and Release: a Paradigm Shift for Understanding Sex Pheromone Quantity in Female Moths

Moths are exemplars of chemical communication, especially with regard to specificity and the minute amounts they use. Yet, little is known about how females manage synthesis and storage of pheromone to maintain release rates attractive to conspecific males and why such small amounts are used. We developed, for the first time, a quantitative model, based on an extensive empirical data set, describing the dynamical relationship among synthesis, storage (titer) and release of pheromone over time in a moth (Heliothis virescens). The model is compartmental, with one major state variable (titer), one time-varying (synthesis), and two constant (catabolism and release) rates. The model was a good fit, suggesting it accounted for the major processes. Overall, we found the relatively small amounts of pheromone stored and released were largely a function of high catabolism rather than a low rate of synthesis. A paradigm shift may be necessary to understand the low amounts released by female moths, away from the small quantities synthesized to the (relatively) large amounts catabolized. Future research on pheromone quantity should focus on structural and physicochemical processes that limit storage and release rate quantities. To our knowledge, this is the first time that pheromone gland function has been modeled for any animal.     

Biodegradation and Metabolic Pathway of the Neonicotinoid Insecticide Thiamethoxam by Labrys portucalensis F11

Thiamethoxam (TMX) is an effective neonicotinoid insecticide. However, its widespread use is detrimental to non-targeted organisms and water systems. This study investigates the biodegradation of this insecticide by Labrys portucalensis F11. After 30 days of incubation in mineral salt medium, L. portucalensis F11 was able to remove 41%, 35% and 100% of a supplied amount of TMX (10.8 mg L⁻¹) provided as the sole carbon and nitrogen source, the sole carbon and sulfur source and as the sole carbon source, respectively. Periodic feeding with sodium acetate as the supplementary carbon source resulted in faster degradation of TMX (10.8 mg L⁻¹); more than 90% was removed in 3 days. The detection and identification of biodegradation intermediates was performed by UPLC-QTOF/MS/MS. The chemical structure of 12 metabolites is proposed. Nitro reduction, oxadiazine ring cleavage and dechlorination are the main degradation pathways proposed. After biodegradation, toxicity was removed as indicated using Aliivibrio fischeri and by assessing the synthesis of an inducible β-galactosidase by an E. coli mutant (Toxi-Chromo test). L. portucalensis F11 was able to degrade TMX under different conditions and could be effective in bioremediation strategies.     

Individual Variation and Repeatability of Sex Pheromone Emission of Female Turnip Moths Agrotis segetum

Individual variation of the female sex pheromone signal in Agrotis segetum was determined by gas chromatographic analysis. The individuals varied extensively, both in absolute and relative amounts of the three major pheromone components; Z5–10:OAc, Z7–12:OAc and Z9–14:OAc. Within individuals there was a strong correspondence between the sex pheromone gland content and the signal actually emitted. Both pheromone amounts and proportions of components were correlated with effluvia and extracts; with coefficients of 0.55 for total amounts and 0.66 for proportions. In addition, the repeatability of emitted pheromone components by individual females over three calling periods was high, with correlation coefficients between 0.43 and 0.72. Variation among individual females, however, was observed. There were no significant differences between wild-collected and laboratory-reared females in average ratios of the major pheromone components in pheromone gland extracts, only in total amounts. The biological significance of the inter-individual variation among females is discussed in the context of population dynamics and sexual selection.     

Tarsi of Male Heliothine Moths Contain Aldehydes and Butyrate Esters as Potential Pheromone Components

The Noctuidae are one of the most speciose moth families and include the genera Helicoverpa and Heliothis. Females use (Z)-11-hexadecenal as the major component of their sex pheromones except for Helicoverpa assulta and Helicoverpa gelotopoeon, both of which utilize (Z)-9-hexadecenal. The minor compounds found in heliothine sex pheromone glands vary with species, but hexadecanal has been found in the pheromone gland of almost all heliothine females so far investigated. In this study, we found a large amount (0.5–1.5 μg) of hexadecanal and octadecanal on the legs of males of four heliothine species, Helicoverpa zea, Helicoverpa armigera, H. assulta, and Heliothis virescens. The hexadecanal was found on and released from the tarsi, and was in much lower levels or not detected on the remaining parts of the leg (tibia, femur, trochanter, and coxa). Lower amounts (0.05–0.5 μg) of hexadecanal were found on female tarsi. This is the first known sex pheromone compound to be identified from the legs of nocturnal moths. Large amounts of butyrate esters (about 16 μg) also were found on tarsi of males with lower amounts on female tarsi. Males deposited the butyrate esters while walking on a glass surface. Decapitation did not reduce the levels of hexadecanal on the tarsi of H. zea males, indicating that hexadecanal production is not under the same neuroendocrine regulation system as the production of female sex pheromone. Based on electroantennogram studies, female antennae had a relatively high response to hexadecanal compared to male antennae. We consider the possible role of aldehydes and butyrate esters as courtship signals in heliothine moths.     

3种杀虫剂亚致死浓度胁迫对桃蚜扩散行为的影响

[目的]明确氟吡呋喃酮、氟啶虫胺腈和环氧虫啶亚致死浓度作用下桃蚜的扩散行为.[方法]实验室条件下测定3种杀虫剂对桃蚜的相对生物活性,并开展各药剂亚致死浓度对桃蚜扩散能力影响研究.[结果]"杀虫剂种类"和"作用时间"是影响桃蚜扩散行为的主要因素;氟吡呋喃酮LC10和LC30处理桃蚜2 h,其扩散率分别为12.38％和36...     

氰戊菊酯和甲氰菊酯对棉铃虫的亚致死效应

本文通过饲喂法测定了氰戊菊酯、甲氰菊酯两种拟除虫菊酯杀虫剂亚致死剂量(LC1与LC50)对棉铃虫3龄幼虫拒食、体重、生长发育以及驱避作用的影响。结果表明,各处理棉铃虫3龄幼虫,取食量均低于对照。处理后48h,LC50剂量以氰戊菊酯拒食活性较高,拒食率为38.65%,且LC50剂量的各处理与对照差异显著。所有处理对棉铃虫幼虫—蛹、蛹—成虫的存活率都有影响。药剂处理后,幼虫的历期延长,幼虫的化蛹也受到影响,出现畸蛹,但各处理畸蛹率均低于15%。亚致死剂量杀虫剂对棉铃虫的生长发育、幼虫体重及蛹重都有抑制作用。在LC1与LC50剂量下,两种药剂对棉铃虫也表现出驱避作用。处理48h,氰戊菊酯LC1与LC50剂量的驱避率分别为76.25%与98.75%。这些研究结果显示,低剂量的拟除虫菊酯对棉铃虫生物学方面存在不良影响。     

The Toxicity,Sublethal Effects,and Biochemical Mechanism of β-Asarone,a Potential Plant-Derived Insecticide,against Bemisia tabaci

Bemisia tabaci is a threat to agriculture worldwide because of its potential to cause devastating damage to various crops. β-asarone is a bioactive pesticidal chemical originating from Acorus calamus (or “Sweet Flag”) plants, and it displays significant lethal effects against insect pests. In this study, we established a baseline of susceptibility to β-asarone from China and patterns of cross-resistance to other popular insecticides. We found that all the 12 field-collected B. tabaci populations exhibited high susceptibility to β-asarone, and there was no cross-resistance detected for other tested insecticides. We subsequently evaluated the sublethal effects of β-asarone on physiology and biochemistry via LC₂₅ treatment (4.7 mg/L). LC₂₅ of β-asarone resulted in prolonged developmental duration and decreased survival rates in B. tabaci nymphs, pseudopupae, and adults. Significant reductions in oviposition duration, fecundity, and hatchability were also observed. Additionally, the metabolic enzyme activity and expression profiles of selected cytochrome P450 monooxygenase (P450) genes following the LC₂₅ treatment of β-asarone suggest that enhanced detoxification via P450s could be involved in the observed sublethal effects. These findings demonstrate the strong toxicity and significant sublethal effects of β-asarone on B. tabaci and suggest that the induced overexpression of P450 genes could be associated with the response to β-asarone.     

Subtleties in Perception and Discrimination by Cabbage Looper Moths, Trichoplusia ni, of the two 14-carbon Acetate Sex Pheromone Components

Three compounds that are emitted by virgin female cabbage looper moths, Trichoplusia ni, (Z)-7-dodecenyl acetate (Z7–12:Ac), (Z)-7-tetradecenyl acetate (Z7–14:Ac), and (Z)-9-tetradecenyl acetate (Z9–14:Ac), are detected by antennal olfactory receptor neurons specialized to detect sex pheromone components. The principal evidence signifying that either or both of Z7–14:Ac and Z9–14:Ac have an effect on male behavior comes from an observed reduction in the numbers of males trapped by Z7–12:Ac paired with a six-component mixture. The evidence conforms to a hypothesis that either or both of these compounds are the basis for discrimination between the two mixtures. However, scant evidence for this hypothesis was obtained in paired-source laboratory wind-tunnel assays, even at airborne concentrations of Z7–14:Ac and Z9–14:Ac that ranged up to 1000× that emitted by a female. Furthermore, there was little evidence from single-source laboratory or field trap assays confirming that Z7–14:Ac and Z9–14:Ac at or above natural stimulus strengths modify the moth's perception of Z7–12:Ac. The data suggest that discrimination of small mixture differences may not be resolvable within the confines of a wind tunnel.     

Physiological Effects of Neonicotinoid Insecticides on Non-Target Aquatic Animals—An Updated Review

In this paper, we review the effects of large-scale neonicotinoid contaminations in the aquatic environment on non-target aquatic invertebrate and vertebrate species. These aquatic species are the fauna widely exposed to environmental changes and chemical accumulation in bodies of water. Neonicotinoids are insecticides that target the nicotinic type acetylcholine receptors (nAChRs) in the central nervous systems (CNS) and are considered selective neurotoxins for insects. However, studies on their physiologic impacts and interactions with non-target species are limited. In researches dedicated to exploring physiologic and toxic outcomes of neonicotinoids, studies relating to the effects on vertebrate species represent a minority case compared to invertebrate species. For aquatic species, the known effects of neonicotinoids are described in the level of organismal, behavioral, genetic and physiologic toxicities. Toxicological studies were reported based on the environment of bodies of water, temperature, salinity and several other factors. There exists a knowledge gap on the relationship between toxicity outcomes to regulatory risk valuation. It has been a general observation among studies that neonicotinoid insecticides demonstrate significant toxicity to an extensive variety of invertebrates. Comprehensive analysis of data points to a generalization that field-realistic and laboratory exposures could result in different or non-comparable results in some cases. Aquatic invertebrates perform important roles in balancing a healthy ecosystem, thus rapid screening strategies are necessary to verify physiologic and toxicological impacts. So far, much of the studies describing field tests on non-target species are inadequate and in many cases, obsolete. Considering the current literature, this review addresses important information gaps relating to the impacts of neonicotinoids on the environment and spring forward policies, avoiding adverse biological and ecological effects on a range of non-target aquatic species which might further impair the whole of the aquatic ecological web.     

新烟碱类杀虫剂的研究进展

本文简要概述了新烟碱类杀虫剂的研究进展、结构特征、作用机制、抗性及治理,并对主要产品的合成方法及应用作了比较全面的综述。     

新烟碱类杀虫剂的进展与合成

对新烟碱类杀虫剂的研究进展及合成方法作了比较全面的综述。着重从中间体角度列举了此类杀虫剂的合成方法 ,并对比中间体的合成。本文进而展示了新烟碱类杀虫剂从性质到合成的相互关联性     

Pheromone Trailing Behavior of the Brown Tree Snake, Boiga irregularis

The ability of snakes to follow pheromone trails has significant consequences for survival and reproduction. Of particular importance is the ability of snakes to locate conspecifics during the breeding season via the detection of pheromone trails. In this study, the ability of male brown tree snakes (Boiga irregularis), a tropical, rear-fanged colubrid, to follow pheromone trails produced by reproductively active conspecifics was tested in the laboratory by using a Y maze. Males displayed a trailing response to both female and male pheromone trails over blank controls. As males of this species display ritualized combat behavior, these responses likely represent both direct and indirect mechanisms, respectively, for the location of potential mates in the wild. Males did not, however, discriminate between male and female trails when given a choice on the Y maze.     

Identification of Novel C20 and C22 Trienoic Acids from Arctiid and Geometrid Female Moths that Produce Polyenyl Type II Sex Pheromone Components

Gas chromatography-mass spectrometry (GC-MS) and GC-electroantennographic detection (EAD) analyses of the sex pheromone extract from a wasp moth, Syntomoides imaon (Lepidoptera: Arctiidae: Syntominae), showed that virgin females produced (Z,Z,Z)-3,6,9-henicosatriene and (Z,Z,Z)-1,3,6,9-henicosatetraene with a trace amount of their C(20) analogs. Identification of the chemical structures was facilitated by comparison with authentic standards and the double-bond positions were confirmed by dimethyl disulfide derivatization of monoenes produced by a diimide reduction. In a field test in the Yonaguni-jima Islands, males of the diurnal species were captured in traps baited with a 1:2 mixture of the above-described synthetic C(21) polyenes. Lipids were extracted from the abdominal integument and its associated oenocytes and peripheral fat bodies. Following derivatization, fatty acid methyl esters (FAMEs) were fractionated by HPLC equipped with an ODS column, and methyl (Z,Z,Z)-11,14,17-icosatrienoate and (Z,Z,Z)-13,16,19-docosatrienoate were identified by GC-MS. These novel C(20) and C(22) acid moieties are longer-chain analogs of linolenic acid, (Z,Z,Z)-9,12,15-octadecatrienoic acid. They are presumed to be biosynthetic precursors of the S. imaon pheromone because the C(21) trienyl component might be formed by decarboxylation of the C(22) acid. On the other hand, the C(20) acid, but not the C(22) acid, was found in FAMEs of Ascotis selenaria cretacea (Lepidoptera: Geometridae), which secretes C(19) pheromone components, (Z,Z,Z)-3,6,9-nonadecatriene and the monoepoxy derivative, indicating that different systems of the chain elongation might play an important role in developing species-specific communication systems mediated with polyunsaturated hydrocarbons and/or epoxy derivatives, components of Type II lepidopteran sex pheromones.     

Behavioral and Sublethal Effects of Structurally Related Lower Terpenes onMyzus persicae

The sesquiterpenes farnesol, caryophyllene oxide, and 2,10-bisaboladien-1-one (patent #9602748) and the monoterpenes citronellol and geraniol were tested for settling inhibition and chronic effects on the aphidMyzus persicae by means of an improved leaf-disk assay. Of these compounds, geraniol, famesol, and the natural bisabolene significantly inhibit settling in choice tests. Furthermore, application of the bisabolene to intactCapsicum annuum leaves did not cause phytotoxicity, but did affect the insects' probing behavior by decreasing the probing activity and the number of intracellular punctures. Both compounds significantly decreased offspring production. Of the compounds tested, the natural product bisabolene could be a promising lead for future development of aphid control agents.