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1.
Leslie Crombie 《Pest management science》1999,55(8):761-774
This paper surveys our work on natural products as potential models for defensive substances against insect and fungal predators. Insecticides and repellents included are pyrethrins, rotenoids, lipid amides, phorbol esters, cordifolia germacranolides, nicandrenoids, mammeins, dihydroagarofuran esters, and cembrene diols. The fungal H-S toxins from Alternaria, and avenacins from oat roots are briefly considered. The avenacins provide an in-situ defence of oat roots against the destructive ‘Take-all’ fungus disease. © 1999 Society of Chemical Industry 相似文献
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BACKGROUND: Mosquitoes are the most important vectors of human pathogens. Wide‐scale use of pesticides has led to the development of resistance to most common insecticide groups. The need to develop novel products that have a low impact on human health and the environment is well established. The toxicity of selected semiochemicals with molecular structures indicative of insecticidal activity was determined against adult Aedes aegypti (L.) and Anopheles quadrimaculatus (Say). The two most active insecticides against Ae. aegypti were also evaluated against Ae. albopictus (Skuse). RESULTS: Fifteen semiochemicals classified as terpenoid alcohols, ketones or carboxylic esters showed toxicity to both mosquito species. Geranyl acetone (LC50 = 38.51 µg cm?2) followed by citronellol (LC50 = 48.55 µg cm?2) were the most toxic compounds to Ae. aegypti, while geraniol and lavonax, with LC50 values of 31.88 and 43.40 µg cm?2, showed the highest toxicity to An. quadrimaculatus. Both geranyl acetone and citronellol were highly toxic to Ae. albopioctus. No semiochemical showed fumigation activity against either species. All semiochemicals persisted for less than 24 h when tested on filter paper. CONCLUSION: Quantification of LC50 values of several semiochemicals against Ae. Aegypti, An. quadrimaculatus and Ae. albopioctus showed that semiochemicals not only modify insect behaviors but also hold potential as potent insecticides for mosquito control programs. Copyright © 2010 Society of Chemical Industry 相似文献
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驱鼠剂的研究现状及展望 总被引：1，自引：0，他引：1
介绍了驱鼠剂的概念、驱避作用机理、研究方法以及国内外驱鼠剂的应用研究进展,提出当前研究中需要解决的问题,并对未来驱鼠剂的发展方向作了展望。 相似文献
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The palatability to captive, mostly laboratory-bred, Norway rats (Rattus norvegicus) of cereal-based baits containing 0.02 g kg-1 brodifacoum, with and without bird-repellent additives, was compared in a no-choice experimental design. Methyl anthranilate (25 g kg-1), dimethyl anthranilate (25 g kg-1) and cinnamamide (2.5 g kg-1) reduced bait consumption by the rats, but all except one rat ate enough bait to receive a lethal dose. Cinnamamide (1 g kg-1), ortho-aminoacetophenone (0.1 g kg-1) and tannic acid (20 g kg-1) did not reduce bait consumption and all rats died after eating baits. The concentration of cinnamamide palatable to rats has only a low and short-lived repellency to birds, so it does not warrant further investigation. However, ortho-aminoacetophenone and tannic acid should now be field-tested for palatability to all three rat species in New Zealand and for repellency to native New Zealand birds. 相似文献
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驱蚊剂定量构效关系(QSAR)的研究对指导高效新驱蚊剂开发、阐明驱蚊剂的驱避机理有重要意义。以40种酰胺类化合物对埃及伊蚊Aedes aegypti的有效保护时间为驱避活性指标,借助PCLIENT(http:∥w w w.vcclab.org/lab/pclient/start.html)量子化学计算软件获得每个化合物的1 773个初始分子描述符,经二元矩阵重排过滤器、多轮末尾淘汰实施特征非线性筛选后,保留了8个物化意义明确的分子描述符,以支持向量回归SVR建立了高精度的非线性QSAR模型,F=8 465,R2=0.999 6。SVR可解释性体系分析结果表明,保留分子描述符对酰胺类驱蚊剂的驱避活性的非线性关系明显。其中,拓扑极性分子表面积TPSA(Tot)对驱避活性影响最为重要,其值越小,活性越高;负电性对驱避活性有较大影响,其值越大,驱避活性越高。 相似文献
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Nineteen novel N-acetyl-2,2-dialkyloxazolidines ( 2 ) and N-acetyl-2-alkyl-4,4-dimethyloxazolidines ( 3 ) were synthesized from commercially available carbonyl compounds and ethanolamine or 2-amino-2-methyl-1-propanol. Their bioactivity against laboratory-reared mosquitoes was compared in patch tests to known N-acetyl-2-alkyloxazolidines ( 1 ) and N,N-diethyl-m-toluamide (deet insect repellent). Isomeric composition measurements by [13C]NMR spectroscopy favoured the Z rotational isomer for samples of 2 (91–96% Z) and the E rotational isomer for samples of 3 (66–71% E), in agreement with molecular mechanics calculations on rotational isomers of model oxazolidines. Samples of 1 were previously shown to exist in solution mostly as the Z isomer (60–70% Z). Within the optimal molecular weight range for these experimental chemicals, the duration of repellency against Aedes aegypti (L.), Anopheles quadrimaculatus Say and Anopheles albimanus Wiedemann generally followed the order: 1 > 2 >deet> 3 . Bioassay data are discussed in relation to the equilibrium populations of rotational isomers for substituted N-acetyloxazolidines. 相似文献
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Several authors have suggested that edible plants could avoid herbivory by mimicking olfactory cues of toxic plants. However, very few studies have been carried out to test this hypothesis. The aims of the present study were to identify the volatiles of three clover species and to test whether a species lacking chemical defences, such as red clover, could avoid being grazed by rabbits by mimicking the volatiles of the cyanogenic white clover. Two main volatiles were identified in all three clover species, and a further two volatiles were present in white clover only. Rabbits presented with a choice between white clover, red clover and red clover sprayed with white clover extract ate significantly more red clover than white or white-flavoured red clover. The results suggest that the volatiles of toxic plants could be used and exploited as a source of natural, safe and effective repellents to control the impact of pest herbivores on plants. 相似文献
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Avian repellents derived from natural products and human food flavorants may be less expensive to register under United States environmental pesticide registration requirements. However, one difficulty faced by workers attempting to target repellents for development is the need to screen large numbers of compounds for activity, as well as consideration of formulation and environmental constraints. In this study, we compare the bird repellent activity of aldehyde-based human food additives and compare the levels of activity with our previously elucidated model for structure–activity relationships (SAR) for bird repellents. We find that a previously elucidated SAR model for identifying acetophenone and anthranilate bird repellents is applicable to predicting the activity of aromatic aldehyde flavorants as well. In particular, of the nine flavorants tested, four, benzaldehyde, cinnamaldehyde, o-tolualdehyde, and o-anisaldehyde, warrant further consideration as bird repellents. L© 1999 Society of Chemical Industry 相似文献
14.
Jürgen Boeckh Heinz Breer Martin Geier Franz-Peter Hoever Bernd-Wieland Krüger Günther Nentwig Hinrich Sass 《Pest management science》1996,48(4):359-373
Starting from a set of known repellent compounds, a general structural framework with high probability for repellent activity was developed by molecular modelling techniques. Synthesis, structure–biological activity relationships of acylated 1,3-aminopropanols on the yellow fever mosquito Aedes aegypti and the properties and activity of the new development candidate compound KBR 3023 on Ae. aegypti, the malaria mosquito Anopheles stephensi, the common house mosquito Culex quinquefasciatus and the stable fly Stomoxys calcitrans are described. The sensory effect of KBR 3023 and deet has been studied in behavioural and neurophysiological investigations on Ae. aegypti and the American cockroach Periplaneta americana. The compounds clearly reduce or even eliminate the approach behaviour towards attractants like host odours or sexual pheromones. Electrophysiological studies on the insects' olfactory receptor organs reveal that certain cell types, which are not involved in perception of the attractive odorants, respond to deet and/or KBR 3023. As soon as one of the compounds is presented together with an attractant, a new input is active in the brain, which adds to the input from other receptors activated by the attractant. This new overall pattern clearly differs from that elicited by the attractant, so that the insect is no longer able to detect the latter. The specificity and mode of action of KBR 3023 was investigated by experiments exploring second-messenger responses elicited in antennal preparations of male P. americana. KBR 3023 induced a rapid increase in the concentration of inositol triphosphate in a dose-dependent and tissue-specific manner; other second-messenger systems were not affected. These observations suggest that KBR 3023 may act via subsets of G-protein-coupled receptors in sensory neurones. 相似文献
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Peter M. Lsel Michael Lindemann Jürgen Scherkenbeck Johann Maier Bernhard Engelhard Colin A. M. Campbell Jim Hardie John A. Pickett Lester J. Wadhams Alfred Elbert Gerhard Thielking 《Pest management science》1996,48(4):293-303
Field experiments employing yellow water-traps with vials releasing methyl salicylate, butyl isothiocyanate, 4-pentenyl isothiocyanate and diethyltoluamide were conducted during the spring migration of Phorodon humuli (Schrank), with the aim of identifying substances which might be used in the field to deter landing on hop plants. Methyl salicylate and the two isothiocyanates reduced trap catches of P. humuli. During the spring of 1994 a slow-release formulation of methyl salicylate and a β-acid-rich hop resin sprayed on to hop plants did not reduce aphid infestations significantly. In autumn cis,cis-nepetalactol, the main component of P. ‘humuli’s sex pheromone, prepared by various synthetic routes, increased trap catches of males and gynoparae equally. Catches of males in pheromone traps situated in a hop garden decreased with increasing trap height. Catches of males in traps charged with increasing doses of the cis,cis-nepetalactol peaked at 1 mg and then plateaued, whereas catches of gynoparae peaked similarly at 1 mg and then decreased. The effects of kairomones from an extract of the primary host, sex pheromone and a visual cue from yellow compared with clear water-traps were additive. The prospects for developing a semiochemicals-based control strategy against P. humuli, using some or all of the above elements, are discussed. 相似文献
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The red bud borer Resseliella oculiperda (Rübs.) is a pest insect of apple trees when rootstocks are grafted with scion buds by 'shield budding'. The female midges are attracted to the wounds of the grafted buds where they lay their eggs. The larvae feed on the cambium and destroy the buds completely or partially, leading to bad union of the buds with the rootstocks. Budding strips are used very often by growers to bind scion buds to rootstocks. These strips cannot prevent midges from reaching the damaged tissue. Chemical treatments applied to the grafts and other types of strip do not provide better protection against the pest and may cause other risks for growers. In orchard experiments in 2000 and 2001, the authors evaluated the repellent action provided by three essential oils and five compounds of plant origin against the midges by impregnating budding strips with them. The essential oils of lavender, Lavandula angustifolia (P. Mill.), and alpha-terpineol decreased the infestation of buds by more than 95 and 80% respectively. The other potential repellents tested [the essential oil of Juniperus virginiana (L.), citronellal, the essential oil of Cinnamomum camphora (L.) J. Presl, R-carvone, linalool and R-fenchone] decreased infestation by 67, 66, 51, 45, 37 and 25% respectively. The formulation and commercial development of budding strips impregnated with lavender oil is discussed. 相似文献
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Chemical irritants useful as repellents for brown treesnakes (Boiga irregularis) were identified. Exposure to various compounds produced a range of intensities for locomotory behavior in snakes. Essential oils comprised of 10 g liter-1 solutions of cedarwood, cinnamon, sage, juniper berry, lavender and rosemary each were potent snake irritants. Brown treesnakes exposed to a 2-s burst of aerosol of these oils exhibited prolonged, violent undirected locomotory behavior. In contrast, exposure to a 10 g liter-1 concentration of ginger oil aerosol caused snakes to locomote, but in a deliberate, directed manner. We also tested specific compounds, all derivative of food and flavor ingredients. 10 g liter-1 solutions delivered as aerosols of m-anisaldehyde, trans-anethole, cineole, cinnamaldehyde, citral, ethyl phenylacetate, eugenol, geranyl acetate or methyl salicylate all acted as potent irritants for brown treesnakes. The individual ingredients were classified using cluster analysis into groups that promoted different levels of response by snakes. This study is the first to systematically investigate the irritant potential of natural products for snakes. These data will be useful in the development of practical pest management tools for snakes. 相似文献
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Michael Londershausen 《Pest management science》1996,48(4):269-292
Intensive use of parasiticides has sometimes led to severe resistance in arthropods and helminths of veterinary importance. In the context of the growing awareness of parasitic diseases, this has created a public demand for effective and safe control agents. During the last two decades considerable knowledge in parasite neurophysiology and endocrinology has accumulated which allows the development of new screening procedures and target-site-directed approaches for the discovery of new drugs. The suitability of this strategic approach is discussed on the basis of recent discoveries of new chemical and natural compounds. In particular, target sites such as GABAA receptors, muscarinic and nicotinic acetylcholine receptors, cuticle synthesis and degradation, ecdysteroid receptors, the calcium release channel and semiochemicals have been selected in order to demonstrate the current approaches to identify new chemical entities, biologically active against nematodes and arthropods. 相似文献
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Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They
represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing
slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more
stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively).
Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were
significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr
s
,P=0.007 and 0.039, respectively) and perennials (Spearmanr
s
,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles. 相似文献
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Paul W. J. Taylor Rebecca Ford 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(1):127-133
Molecular diagnostic techniques have been developed to differentiate the Ascochyta pathogens that infect cool season food and feed legumes, as well as to improve the sensitivity of detecting latent infection
in plant tissues. A seed sampling technique was developed to detect a 1% level of infection by Ascochyta rabiei in commercial chickpea seed. The Ascochyta pathogens were shown to be genetically diverse in countries where the pathogen and host have coexisted for a long time. However,
where the pathogen was recently introduced, such as A. rabiei to Australia, the level of diversity remained relatively low, even as the pathogen spread to all chickpea-growing areas.
Pathogenic variability of A. rabiei and Ascochyta pinodes pathogens in chickpea and field pea respectively, appears to be quantitative, where measures of disease severity were based
on aggressiveness (quantitative level of infection) rather than on true qualitative virulence. In contrast, qualitative differences
in pathogenicity in lentil and faba bean genotypes indicated the existence of pathotypes of Ascochyta lentis and Ascochyta fabae. Therefore, reports of pathotype discrimination based on quantitative differences in pathogenicity in a set of specific genotypes
is questionable for several of the ascochyta-legume pathosystems such as A. rabiei and A. pinodes. This is not surprising since host resistance to these pathogens has been reported to be mainly quantitative, making it difficult
for the pathogen to overcome specific resistance genes and form pathotypes. For robust pathogenicity assessment, there needs
to be consistency in selection of differential host genotypes, screening conditions and disease evaluation techniques for
each of the Ascochyta sp. in legume-growing countries throughout the world. Nevertheless, knowledge of pathotype diversity and aggressiveness within
populations is important in the selection of resistant genotypes. 相似文献