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Sample records for piercing-sucking insect myzus

  1. Induced plant resistance as a pest management tactic on piercing sucking insects of sesame crop

    Directory of Open Access Journals (Sweden)

    M. F. Mahmoud

    2013-09-01

    Full Text Available Sesame, Sesamum indicum L. is the most oil seed crop of the world and also a major oil seed crop of Egypt. One of the major constraints in its production the damage caused by insect pests, particularly sucking insects which suck the cell sap from leaves, flowers and capsules. Impact of three levels of potassin-F, salicylic acid and combination between them on reduction infestation of Stink bug Nezara viridula L., Mirid bug Creontiades sp., Green peach aphid Myzus persicae (Sulzer, Leafhopper Empoasca lybica de Berg and Whitefly Bemisia tabaci (Gennadius of sesame crop cultivar Shandawil 3 was carried out during 2010-2011 crop season at Experimental farm, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt. Also, the impacts of potassin-F and salicylic acid on yield production of sesame were studied. Results indicated that percent of reduction of infestation by N. viridula, M. persicae, Creontiades sp., E. lybicae, B. tabaci and phyllody disease were significantly higher at Level 2 (Potassin-F= 2.5 cm/l, Salicylic acid= 0.001 M and Potassin + Salicylic= 2.5 cm/l + 0.001 M and consequently higher seed yield per plant were obtained.

  2. New insights into an RNAi approach for plant defence against piercing-sucking and stem-borer insect pests.

    Science.gov (United States)

    Li, Haichao; Guan, Ruobing; Guo, Huimin; Miao, Xuexia

    2015-11-01

    Insect double-stranded (ds)RNA expression in transgenic crops can increase plant resistance to biotic stress; however, creating transgenic crops to defend against every insect pest is impractical. Arabidopsis Mob1A is required for organ growth and reproduction. When Arabidopsis roots were soaked in dsMob1A, the root lengths and numbers were significantly suppressed and plants could not bolt or flower. Twenty-four hours after rice roots were immersed in fluorescent-labelled dsEYFP (enhanced yellow fluorescent protein), fluorescence was observed in the rice sheath and stem and in planthoppers feeding on the rice. The expression levels of Ago and Dicer in rice and planthoppers were induced by dsEYFP. When rice roots were soaked in dsActin, their growth was also significantly suppressed. When planthoppers or Asian corn borers fed on rice or maize that had been irrigated with a solution containing the dsRNA of an insect target gene, the insect's mortality rate increased significantly. Our results demonstrate that dsRNAs can be absorbed by crop roots, trigger plant and insect RNAi and enhance piercing-sucking and stem-borer insect mortality rates. We also confirmed that dsRNA was stable under outdoor conditions. These results indicate that the root dsRNA soaking can be used as a bioinsecticide strategy during crop irrigation. © 2015 John Wiley & Sons Ltd.

  3. Relationship Between Piercing-Sucking Insect Control and Internal Lint and Seed Rot in Southeastern Cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Medrano, Enrique G; Bell, Alois A; Greene, Jeremy K; Roberts, Phillip M; Bacheler, Jack S; Marois, James J; Wright, David L; Esquivel, Jesus F; Nichols, Robert L; Duke, Sara

    2015-08-01

    In 1999, crop consultants scouting for stink bugs (Hemiptera spp.) in South Carolina discovered a formerly unobserved seed rot of cotton that caused yield losses ranging from 10 to 15% in certain fields. The disease has subsequently been reported in fields throughout the southeastern Cotton Belt. Externally, diseased bolls appeared undamaged; internally, green fruit contain pink to dark brown, damp, deformed lint, and necrotic seeds. In greenhouse experiments, we demonstrated transmission of the opportunistic bacterium Pantoea agglomerans by the southern green stink bug, Nezara viridula (L.). Here, green bolls were sampled from stink bug management plots (insecticide protected or nontreated) from four South Atlantic coast states (North Carolina, South Carolina, Georgia, and Florida) to determine disease incidence in the field and its association with piercing-sucking insects feeding. A logistic regression analysis of the boll damage data revealed that disease was 24 times more likely to occur (P = 0.004) in bolls collected from plots in Florida, where evidence of pest pressure was highest, than in bolls harvested in NC with the lowest detected insect pressure. Fruit from plots treated with insecticide, a treatment which reduced transmission agent numbers, were 4 times less likely to be diseased than bolls from unprotected sites (P = 0.002). Overall, punctured bolls were 125 times more likely to also have disease symptoms than nonpunctured bolls, irrespective of whether or not plots were protected with insecticides (P = 0.0001). Much of the damage to cotton bolls that is commonly attributed to stink bug feeding is likely the resulting effect of vectored pathogens. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  4. A transgenic approach to control hemipteran insects by expressing insecticidal genes under phloem-specific promoters

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    Javaid, Shaista; Amin, Imran; Jander, Georg; Mukhtar, Zahid; Saeed, Nasir A.; Mansoor, Shahid

    2016-01-01

    The first generation transgenic crops used strong constitutive promoters for transgene expression. However, tissue-specific expression is desirable for more precise targeting of transgenes. Moreover, piercing/sucking insects, which are generally resistant to insecticidal Bacillus thuringiensis (Bt) proteins, have emerged as a major pests since the introduction of transgenic crops expressing these toxins. Phloem-specific promoters isolated from Banana bunchy top virus (BBTV) were used for the expression of two insecticidal proteins, Hadronyche versuta (Blue Mountains funnel-web spider) neurotoxin (Hvt) and onion leaf lectin, in tobacco (Nicotiana tabacum). Here we demonstrate that transgenic plants expressing Hvt alone or in combination with onion leaf lectin are resistant to Phenacoccus solenopsis (cotton mealybug), Myzus persicae (green peach aphids) and Bemisia tabaci (silver leaf whitefly). The expression of both proteins under different phloem-specific promoters resulted in close to 100% mortality and provided more rapid protection than Hvt alone. Our results suggest the employment of the Hvt and onion leaf lectin transgenic constructs at the commercial level will reduce the use of chemical pesticides for control of hemipteran insect pests. PMID:27708374

  5. New technologies in electrical penetration graph (EPG) monitors of insect feeding and their applications for 21st century entomology

    Science.gov (United States)

    Electrical penetration graph (EPG) monitoring of insect feeding is a rigorous means of observing and quantifying feeding behaviors of piercing-sucking arthropods, as well as fine details of chewing and oviposition behaviors not observable visually. While EPG was originally invented nearly 50 years ...

  6. Qualitative Sybr Green real-time detection of single nucleotide polymorphisms responsible for target-site resistance in insect pests: the example of Myzus persicae and Musca domestica.

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    Puggioni, V; Chiesa, O; Panini, M; Mazzoni, E

    2017-02-01

    Chemical insecticides have been widely used to control insect pests, leading to the selection of resistant populations. To date, several single nucleotide polymorphisms (SNPs) have already been associated with insecticide resistance, causing reduced sensitivity to many classes of products. Monitoring and detection of target-site resistance is currently one of the most important factors for insect pest management strategies. Several methods are available for this purpose: automated and high-throughput techniques (i.e. TaqMan or pyrosequencing) are very costly; cheaper alternatives (i.e. RFLP or PASA-PCRs) are time-consuming and limited by the necessity of a final visualization step. This work presents a new approach (QSGG, Qualitative Sybr Green Genotyping) which combines the specificity of PASA-PCR with the rapidity of real-time PCR analysis. The specific real-time detection of Cq values of wild-type or mutant alleles (amplified used allele-specific primers) allows the calculation of ΔCqW-M values and the consequent identification of the genotypes of unknown samples, on the basis of ranges previously defined with reference clones. The methodology is applied here to characterize mutations described in Myzus persicae and Musca domestica and we demonstrate it represents a valid, rapid and cost-effective technique that can be adopted for monitoring target-site resistance in field populations of these and other insect species.

  7. Perception of insect feeding by plants.

    Science.gov (United States)

    Bonaventure, G

    2012-11-01

    The recognition of phytophagous insects by plants induces a set of very specific responses aimed at deterring tissue consumption and reprogramming metabolism and development of the plant to tolerate the herbivore. The recognition of insects by plants requires the plant's ability to perceive chemical cues generated by the insects and to distinguish a particular pattern of tissue disruption. Relatively little is known about the molecular basis of insect perception by plants and the signalling mechanisms directly associated with this perception. Importantly, the insect feeding behaviour (piercing-sucking versus chewing) is a decisive determinant of the plant's defence response, and the mechanisms used to perceive insects from different feeding guilds may be distinct. During insect feeding, components of the saliva of chewing or piercing-sucking insects come into contact with plant cells, and elicitors or effectors present in this insect-derived fluid are perceived by plant cells to initiate the activation of specific signalling cascades. Although receptor-ligand interactions controlling insect perception have yet not been molecularly described, a significant number of regulatory components acting downstream of receptors and involved in the activation of defence responses against insects has been reported. Some of these regulators mediate changes in the phytohormone network, while others directly control gene expression or the redox state of the cell. These processes are central in the orchestration of plant defence responses against insects.

  8. A review on the complexity of insect-plant interactions under varying levels of resources and host resistance: the case of Myzus persicae-Prunus persica

    Directory of Open Access Journals (Sweden)

    Verdugo, JA.

    2016-01-01

    Full Text Available Introduction. Insect-plant interactions are affected directly or indirectly by stress factors. The effect of environmental resource availability on insect-plant interactions is here reviewed. Subsequently, the analysis focuses on aphid-host plant interactions, particularly in the system composed by the green peach aphid Myzus persicae and its primary host plant Prunus persica. Literature. Plant defenses arise in two ways: resistance and tolerance, both are affected by abiotic factors. The information gathered from studies (n = 29 on plant-aphid interactions addressing the reduction in water availability on plant resistance, showed that in 41,4% of the studies, drought stress elicits lower resistance, while 34.5%, 20.1% and 3.4%, showed higher, no change and conditional effects on plant resistance, respectively. Conclusions. Water stress elicits mixed effects on plant resistance to aphids. However, the literature review also suggests that cultural practices play a role in the fate of the peach-aphid interactions, whereas the development of predictive models aimed to assist crop-pest management systems still requires more basic information. Aphid responses to plant defenses under stressed conditions are still largely unexplored.

  9. Effector proteins that modulate plant--insect interactions.

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    Hogenhout, Saskia A; Bos, Jorunn I B

    2011-08-01

    Insect herbivores have highly diverse life cycles and feeding behaviors. They establish close interactions with their plant hosts and suppress plant defenses. Chewing herbivores evoke characteristic defense responses distinguishable from general mechanical damage. In addition, piercing-sucking hemipteran insects display typical feeding behavior that suggests active suppression of plant defense responses. Effectors that modulate plant defenses have been identified in the saliva of these insects. Tools for high-throughput effector identification and functional characterization have been developed. In addition, in some insect species it is possible to silence gene expression by RNAi. Together, this technological progress has enabled the identification of insect herbivore effectors and their targets that will lead to the development of novel strategies for pest resistances in plants.

  10. Structural mouthpart interaction evolved already in the earliest lineages of insects.

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    Blanke, Alexander; Rühr, Peter T; Mokso, Rajmund; Villanueva, Pablo; Wilde, Fabian; Stampanoni, Marco; Uesugi, Kentaro; Machida, Ryuichiro; Misof, Bernhard

    2015-08-01

    In butterflies, bees, flies and true bugs specific mouthparts are in close contact or even fused to enable piercing, sucking or sponging of particular food sources. The common phenomenon behind these mouthpart types is a complex composed of several consecutive mouthparts which structurally interact during food uptake. The single mouthparts are thus only functional in conjunction with other adjacent mouthparts, which is fundamentally different to biting-chewing. It is, however, unclear when structural mouthpart interaction (SMI) evolved since this principle obviously occurred multiple times independently in several extant and extinct winged insect groups. Here, we report a new type of SMI in two of the earliest wingless hexapod lineages--Diplura and Collembola. We found that the mandible and maxilla interact with each other via an articulatory stud at the dorsal side of the maxillary stipes, and they are furthermore supported by structures of the hypopharynx and head capsule. These interactions are crucial stabilizing elements during food uptake. The presence of SMI in these ancestrally wingless insects, and its absence in those crustacean groups probably ancestral to insects, indicates that SMI is a groundplan apomorphy of insects. Our results thus contradict the currently established view of insect mouthpart evolution that biting-chewing mouthparts without any form of SMI are the ancestral configuration. Furthermore, SMIs occur in the earliest insects in a high anatomical variety. SMIs in stemgroup representatives of insects may have triggered efficient exploitation and fast adaptation to new terrestrial food sources much earlier than previously supposed.

  11. Identification of aphid salivary proteins: a proteomic investigation of Myzus persicae.

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    Harmel, N; Létocart, E; Cherqui, A; Giordanengo, P; Mazzucchelli, G; Guillonneau, F; De Pauw, E; Haubruge, E; Francis, F

    2008-04-01

    The role of insect saliva in the first contact between an insect and a plant is crucial during feeding. Some elicitors, particularly in insect regurgitants, have been identified as inducing plant defence reactions. Here, we focused on the salivary proteome of the green peach aphid, Myzus persicae. Proteins were either directly in-solution digested or were separated by 2D SDS-PAGE before trypsin digestion. Resulting peptides were then identified by mass spectrometry coupled with database investigations. A homemade database was constituted of expressed sequence tags from the pea aphid Acyrtosiphon pisum and M. persicae. The databases were used to identify proteins related to M. persicae with a nonsequenced genome. This procedure enabled us to discover glucose oxidase, glucose dehydrogenase, NADH dehydrogenase, alpha-glucosidase and alpha-amylase in M. persicae saliva. The presence of these enzymes is discussed in terms of plant-aphid interactions.

  12. Double strand RNA delivery system for plant-sap-feeding insects.

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    Ghosh, Saikat Kumar B; Hunter, Wayne B; Park, Alexis L; Gundersen-Rindal, Dawn E

    2017-01-01

    Double-stranded RNA (dsRNA)-mediated gene silencing, also known as RNA interference (RNAi), has been a breakthrough technology for functional genomic studies and represents a potential tool for the management of insect pests. Since the inception of RNAi numerous studies documented successful introduction of exogenously synthesized dsRNA or siRNA into an organism triggering highly efficient gene silencing through the degradation of endogenous RNA homologous to the presented siRNA. Managing hemipteran insect pests, especially Halyomorpha halys (Stål) (Heteroptera: Pentatomidae), the brown marmorated stink bug (BMSB), is critical to food productivity. BMSB was recently introduced into North America where it is both an invasive agricultural pest of high value specialty, row, and staple crops, as well as an indoor nuisance pest. RNAi technology may serve as a viable tool to manage this voracious pest, but delivery of dsRNA to piercing-sucking insects has posed a tremendous challenge. Effective and practical use of RNAi as molecular biopesticides for biocontrol of insects like BMSB in the environment requires that dsRNAs be delivered in vivo through ingestion. Therefore, the key challenge for molecular biologists in developing insect-specific molecular biopesticides is to find effective and reliable methods for practical delivery of stable dsRNAs such as through oral ingestion. Here demonstrated is a reliable delivery system of effective insect-specific dsRNAs through oral feeding through a new delivery system to induce a significant decrease in expression of targeted genes such as JHAMT and Vg. This state-of-the-art delivery method overcomes environmental delivery challenges so that RNAi is induced through insect-specific dsRNAs orally delivered to hemipteran and other insect pests.

  13. Double strand RNA delivery system for plant-sap-feeding insects

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    Ghosh, Saikat Kumar B.; Hunter, Wayne B.; Park, Alexis L.; Gundersen-Rindal, Dawn E.

    2017-01-01

    Double-stranded RNA (dsRNA)-mediated gene silencing, also known as RNA interference (RNAi), has been a breakthrough technology for functional genomic studies and represents a potential tool for the management of insect pests. Since the inception of RNAi numerous studies documented successful introduction of exogenously synthesized dsRNA or siRNA into an organism triggering highly efficient gene silencing through the degradation of endogenous RNA homologous to the presented siRNA. Managing hemipteran insect pests, especially Halyomorpha halys (Stål) (Heteroptera: Pentatomidae), the brown marmorated stink bug (BMSB), is critical to food productivity. BMSB was recently introduced into North America where it is both an invasive agricultural pest of high value specialty, row, and staple crops, as well as an indoor nuisance pest. RNAi technology may serve as a viable tool to manage this voracious pest, but delivery of dsRNA to piercing-sucking insects has posed a tremendous challenge. Effective and practical use of RNAi as molecular biopesticides for biocontrol of insects like BMSB in the environment requires that dsRNAs be delivered in vivo through ingestion. Therefore, the key challenge for molecular biologists in developing insect-specific molecular biopesticides is to find effective and reliable methods for practical delivery of stable dsRNAs such as through oral ingestion. Here demonstrated is a reliable delivery system of effective insect-specific dsRNAs through oral feeding through a new delivery system to induce a significant decrease in expression of targeted genes such as JHAMT and Vg. This state-of-the-art delivery method overcomes environmental delivery challenges so that RNAi is induced through insect-specific dsRNAs orally delivered to hemipteran and other insect pests. PMID:28182760

  14. Pest insects at tobacco (Nicotiana tabacum L.) in Strumica region, Republic of Macedonia

    OpenAIRE

    Spasov, Dusan; Spasova, Dragica; Atanasova, Biljana; Serafimova, Mimoza

    2013-01-01

    The studies that were conducted in 2011 and 2012 about the pest insects at tobacco, at four localities in Strumica region, showed that the most important insect pests that cause damage to tobacco leaves are: the green peach aphid – Myzus persicae Sulz. (Homoptera: Aphididae), the onion trips – Thrips tabaci Lind. (Thysanoptera: Thripidae) and the tobacco flea beetle – Epitrix hirtipennis Melsh. (Coleoptera: Chrysomelidae). In both years of research the greatest number showed Myzus persica...

  15. Spatial patterns of aflatoxin levels in relation to ear-feeding insect damage in pre-harvest corn.

    Science.gov (United States)

    Ni, Xinzhi; Wilson, Jeffrey P; Buntin, G David; Guo, Baozhu; Krakowsky, Matthew D; Lee, R Dewey; Cottrell, Ted E; Scully, Brian T; Huffaker, Alisa; Schmelz, Eric A

    2011-07-01

    Key impediments to increased corn yield and quality in the southeastern US coastal plain region are damage by ear-feeding insects and aflatoxin contamination caused by infection of Aspergillus flavus. Key ear-feeding insects are corn earworm, Helicoverpa zea, fall armyworm, Spodoptera frugiperda, maize weevil, Sitophilus zeamais, and brown stink bug, Euschistus servus. In 2006 and 2007, aflatoxin contamination and insect damage were sampled before harvest in three 0.4-hectare corn fields using a grid sampling method. The feeding damage by each of ear/kernel-feeding insects (i.e., corn earworm/fall armyworm damage on the silk/cob, and discoloration of corn kernels by stink bugs), and maize weevil population were assessed at each grid point with five ears. The spatial distribution pattern of aflatoxin contamination was also assessed using the corn samples collected at each sampling point. Aflatoxin level was correlated to the number of maize weevils and stink bug-discolored kernels, but not closely correlated to either husk coverage or corn earworm damage. Contour maps of the maize weevil populations, stink bug-damaged kernels, and aflatoxin levels exhibited an aggregated distribution pattern with a strong edge effect on all three parameters. The separation of silk- and cob-feeding insects from kernel-feeding insects, as well as chewing (i.e., the corn earworm and maize weevil) and piercing-sucking insects (i.e., the stink bugs) and their damage in relation to aflatoxin accumulation is economically important. Both theoretic and applied ramifications of this study were discussed by proposing a hypothesis on the underlying mechanisms of the aggregated distribution patterns and strong edge effect of insect damage and aflatoxin contamination, and by discussing possible management tactics for aflatoxin reduction by proper management of kernel-feeding insects. Future directions on basic and applied research related to aflatoxin contamination are also discussed.

  16. Spatial Patterns of Aflatoxin Levels in Relation to Ear-Feeding Insect Damage in Pre-Harvest Corn

    Directory of Open Access Journals (Sweden)

    Alisa Huffaker

    2011-07-01

    Full Text Available Key impediments to increased corn yield and quality in the southeastern US coastal plain region are damage by ear-feeding insects and aflatoxin contamination caused by infection of Aspergillus flavus. Key ear-feeding insects are corn earworm, Helicoverpa zea, fall armyworm, Spodoptera frugiperda, maize weevil, Sitophilus zeamais, and brown stink bug, Euschistus servus. In 2006 and 2007, aflatoxin contamination and insect damage were sampled before harvest in three 0.4-hectare corn fields using a grid sampling method. The feeding damage by each of ear/kernel-feeding insects (i.e., corn earworm/fall armyworm damage on the silk/cob, and discoloration of corn kernels by stink bugs, and maize weevil population were assessed at each grid point with five ears. The spatial distribution pattern of aflatoxin contamination was also assessed using the corn samples collected at each sampling point. Aflatoxin level was correlated to the number of maize weevils and stink bug-discolored kernels, but not closely correlated to either husk coverage or corn earworm damage. Contour maps of the maize weevil populations, stink bug-damaged kernels, and aflatoxin levels exhibited an aggregated distribution pattern with a strong edge effect on all three parameters. The separation of silk- and cob-feeding insects from kernel-feeding insects, as well as chewing (i.e., the corn earworm and maize weevil and piercing-sucking insects (i.e., the stink bugs and their damage in relation to aflatoxin accumulation is economically important. Both theoretic and applied ramifications of this study were discussed by proposing a hypothesis on the underlying mechanisms of the aggregated distribution patterns and strong edge effect of insect damage and aflatoxin contamination, and by discussing possible management tactics for aflatoxin reduction by proper management of kernel-feeding insects. Future directions on basic and applied research related to aflatoxin contamination are also

  17. High-throughput phenotyping of plant resistance to aphids by automated video tracking.

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    Kloth, Karen J; Ten Broeke, Cindy Jm; Thoen, Manus Pm; Hanhart-van den Brink, Marianne; Wiegers, Gerrie L; Krips, Olga E; Noldus, Lucas Pjj; Dicke, Marcel; Jongsma, Maarten A

    2015-01-01

    Piercing-sucking insects are major vectors of plant viruses causing significant yield losses in crops. Functional genomics of plant resistance to these insects would greatly benefit from the availability of high-throughput, quantitative phenotyping methods. We have developed an automated video tracking platform that quantifies aphid feeding behaviour on leaf discs to assess the level of plant resistance. Through the analysis of aphid movement, the start and duration of plant penetrations by aphids were estimated. As a case study, video tracking confirmed the near-complete resistance of lettuce cultivar 'Corbana' against Nasonovia ribisnigri (Mosely), biotype Nr:0, and revealed quantitative resistance in Arabidopsis accession Co-2 against Myzus persicae (Sulzer). The video tracking platform was benchmarked against Electrical Penetration Graph (EPG) recordings and aphid population development assays. The use of leaf discs instead of intact plants reduced the intensity of the resistance effect in video tracking, but sufficiently replicated experiments resulted in similar conclusions as EPG recordings and aphid population assays. One video tracking platform could screen 100 samples in parallel. Automated video tracking can be used to screen large plant populations for resistance to aphids and other piercing-sucking insects.

  18. Interaction of Phytophagous Insects with Salmonella enterica on Plants and Enhanced Persistence of the Pathogen with Macrosteles quadrilineatus Infestation or Frankliniella occidentalis Feeding: e79404

    National Research Council Canada - National Science Library

    José Pablo Soto-Arias; Russell Groves; Jeri D Barak

    2013-01-01

    ... S. enterica populations were found on leaves infested with Macrosteles quadrilineatus. In contrast, pathogen populations among plants exposed to Frankliniella occidentalis or Myzus persicae were similar to those without insects...

  19. Purification and characterisation of a 31-kDa chitinase from the Myzus Persicae aphid: a target for hemiptera biocontrol.

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    Francis, Frédéric; Saguez, Julien; Cherqui, Anas; Vandermoten, Sophie; Vincent, Charles; Versali, Marie-France; Dommès, Jacques; De Pauw, Edwin; Giordanengo, Philippe; Haubruge, Eric

    2012-03-01

    Hydrolytic enzymes involved in chitin degradation are important to allow moulting during insect development. Chitinases are interesting targets to disturb growth and develop alternative strategies to control insect pests. In this work, a chitinase from the aphid Myzus persicae was purified with a 36-fold purification rate in a three step procedure by ammonium sulphate fractionation, anion-exchange chromatography on a DEAE column and on an affinity Concanavalin A column. The purified chitinase purity assessed by 1D and 2D SDS-PAGE revealed a single band and three spots at 31 kDa, respectively. Chitinases were found to have high homologies with Concanavalins A and B, two chitinase-related proteins, a fungal endochitinase and an aphid acetylhydrolase by peptide identification by Maldi-Tof-Tof. The efficiency of two potent chitinase inhibitors, namely allosamidin and psammaplin A, was tested and showed significant rate of enzymatic inhibition.

  20. Biomechanical Properties of Hemlocks: A Novel Approach to Evaluating Physical Barriers of the Plant–Insect Interface and Resistance to a Phloem-Feeding Herbivore

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    Paul Ayayee

    2014-06-01

    Full Text Available Micromechanical properties that help mediate herbivore access may be particularly important when considering herbivorous insects that feed with piercing-sucking stylets. We used microindentation to quantify the micromechanical properties of hemlock, Tsuga spp., to quantify the hardness of the feeding site of the invasive hemlock woolly adelgid, Adelges tsugae. We measured hardness of the hemlock leaf cushion, the stylet insertion point of the adelgid, across four seasons in a 1 y period for four hemlock species growing in a common garden, including eastern, western, mountain, and northern Japanese hemlocks. Leaf cushion hardness was highest in the fall and winter and lowest in summer for all species. Northern Japanese hemlock had relatively greater hardness than the remaining species. Our data contributes an additional perspective to the existing framework within which greater susceptibility and subsequent mortality of eastern hemlocks is observed. The potential application of microindentation to understanding the nature and relevance of plant mechanical defenses in plant–herbivore interactions is also demonstrated and highlighted.

  1. Methods of correlating electropenetrography waveform data to Hemipteran probing behavior and pathogen transmission

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    Hemipteran feeding behavior cannot be visualized within plant tissues by researchers studying probing and/or transmission attributes of some economically important plant pathogens transmitted by these piercing sucking insects. Electropenetrography (EPG) is currently the most precise method for study...

  2. Proteomic analysis of Arabidopsis thaliana (L.) Heynh responses to a generalist sucking pest (Myzus persicae Sulzer).

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    Truong, D-H; Bauwens, J; Delaplace, P; Mazzucchelli, G; Lognay, G; Francis, F

    2015-11-01

    Herbivorous insects can cause severe cellular changes to plant foliage following infestations, depending on feeding behaviour. Here, a proteomic study was conducted to investigate the influence of green peach aphid (Myzus persicae Sulzer) as a polyphagous pest on the defence response of Arabidopsis thaliana (L.) Heynh after aphid colony establishment on the host plant (3 days). Analysis of about 574 protein spots on 2-DE gels revealed 31 differentially expressed protein spots. Twenty out of these 31 differential proteins were selected for analysis by mass spectrometry. In 12 of the 20 analysed spots, we identified seven and nine proteins using MALDI-TOF-MS and LC-ESI-MS/MS, respectively. Of the analysed spots, 25% contain two proteins. Different metabolic pathways were modulated in Arabidopsis leaves according to aphid feeding: most corresponded to carbohydrate, amino acid and energy metabolism, photosynthesis, defence response and translation. This paper has established a survey of early alterations induced in the proteome of Arabidopsis by M. persicae aphids. It provides valuable insights into the complex responses of plants to biological stress, particularly for herbivorous insects with sucking feeding behaviour.

  3. [The origin and evolution of parasitism on terrestrial vertebrates in insects, mites, and ticks].

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    Balashov, Iu S

    2006-01-01

    Coexistence of terrestrial vertebrates and arthropods has been continuing over 200 million years; various forms of parasitism originated independently in various groups of arthropods during this period. The association of Acari and insects with nests and shelters of their hosts (nidicoly) played the main role in the origin of parasitism in these major groups of arthropods. The primary step in the evolution of parasitism was the permanent habitation in nests and borrows of mammals and birds in Mesozoic era. The second step was a substitution of various forms of schizophagy by the regular feeding on products of vital activity and dead parts of host body. The next step was the feeding on various body parts of vertebrate hosts, namely skin, hair, feathers, external excreta, and drops of blood. The final step was the development of the ability to damage skin and suck out the blood of vertebrates. In some taxa of astigmatid mites the parasitism on birds originated from phoresy: hypopi (heteromorphous deutonymphs) obtained the ability to absorb the liquid nutrients from hair follicles and subcutaneous tissues through the cuticle. The development of haematophagous feeding on mammals in several families of Diptera was the second way of the origin of parasitism. Highly mobile dipterans with the piercing-sucking or licking mouthparts were able to change easily from the accidental puncturing of the host skin or licking of the blood, pus, and mucus to the obligatory haematophagy. The evolution of some arthropod taxa did not went beyond a primary domination of spatial relations, as in many astigmatid mites, or trophic relations in the form of micropredatory, as in the haematophagous Diptera.

  4. Genomic resources for Myzus persicae: EST sequencing, SNP identification, and microarray design

    Directory of Open Access Journals (Sweden)

    Malloch Gaynor

    2007-11-01

    Full Text Available Abstract Background The green peach aphid, Myzus persicae (Sulzer, is a world-wide insect pest capable of infesting more than 40 plant families, including many crop species. However, despite the significant damage inflicted by M. persicae in agricultural systems through direct feeding damage and by its ability to transmit plant viruses, limited genomic information is available for this species. Results Sequencing of 16 M. persicae cDNA libraries generated 26,669 expressed sequence tags (ESTs. Aphids for library construction were raised on Arabidopsis thaliana, Nicotiana benthamiana, Brassica oleracea, B. napus, and Physalis floridana (with and without Potato leafroll virus infection. The M. persicae cDNA libraries include ones made from sexual and asexual whole aphids, guts, heads, and salivary glands. In silico comparison of cDNA libraries identified aphid genes with tissue-specific expression patterns, and gene expression that is induced by feeding on Nicotiana benthamiana. Furthermore, 2423 genes that are novel to science and potentially aphid-specific were identified. Comparison of cDNA data from three aphid lineages identified single nucleotide polymorphisms that can be used as genetic markers and, in some cases, may represent functional differences in the protein products. In particular, non-conservative amino acid substitutions in a highly expressed gut protease may be of adaptive significance for M. persicae feeding on different host plants. The Agilent eArray platform was used to design an M. persicae oligonucleotide microarray representing over 10,000 unique genes. Conclusion New genomic resources have been developed for M. persicae, an agriculturally important insect pest. These include previously unknown sequence data, a collection of expressed genes, molecular markers, and a DNA microarray that can be used to study aphid gene expression. These resources will help elucidate the adaptations that allow M. persicae to develop compatible

  5. Insecticide resistance mechanisms in the green peach aphid Myzus persicae (Hemiptera: Aphididae I: A transcriptomic survey.

    Directory of Open Access Journals (Sweden)

    Andrea X Silva

    Full Text Available BACKGROUND: Insecticide resistance is one of the best examples of rapid micro-evolution found in nature. Since the development of the first synthetic insecticide in 1939, humans have invested considerable effort to stay ahead of resistance phenotypes that repeatedly develop in insects. Aphids are a group of insects that have become global pests in agriculture and frequently exhibit insecticide resistance. The green peach aphid, Myzus persicae, has developed resistance to at least seventy different synthetic compounds, and different insecticide resistance mechanisms have been reported worldwide. METHODOLOGY/PRINCIPAL FINDINGS: To further characterize this resistance, we analyzed genome-wide transcriptional responses in three genotypes of M. persicae, each exhibiting different resistance mechanisms, in response to an anti-cholinesterase insecticide. The sensitive genotype (exhibiting no resistance mechanism responded to the insecticide by up-regulating 183 genes primarily ones related to energy metabolism, detoxifying enzymes, proteins of extracellular transport, peptidases and cuticular proteins. The second genotype (resistant through a kdr sodium channel mutation, up-regulated 17 genes coding for detoxifying enzymes, peptidase and cuticular proteins. Finally, a multiply resistant genotype (carrying kdr and a modified acetylcholinesterase, up-regulated only 7 genes, appears not to require induced insecticide detoxification, and instead down-regulated many genes. CONCLUSIONS/SIGNIFICANCE: This study suggests strongly that insecticide resistance in M. persicae is more complex that has been described, with the participation of a broad array of resistance mechanisms. The sensitive genotype exhibited the highest transcriptional plasticity, accounting for the wide range of potential adaptations to insecticides that this species can evolve. In contrast, the multiply resistant genotype exhibited a low transcriptional plasticity, even for the expression

  6. Effects of mti-2 Transgenic Potato Plants on the Aphid Myzus persicae (Sternorrhyncha: Aphididae

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    Julien Saguez

    2010-01-01

    Full Text Available Overexpressed in transgenic plants, protease inhibitors showed insecticidal effects against several insect taxa. We transformed potato internodes with the mustard trypsin inhibitor mti-2 gene. Among the 35 independent transgenic potato lines obtained via Agrobacterium tumefasciens transformation, four (DM6, DM7, DM11, and DM19 were selected for their high level of MTI-2 (at least to 30% of trypsin activity inhibition. Feeding assays were carried out to evaluate their effects on the green-peach aphid, Myzus persicae (Sternorrhyncha: Aphididae. Prereproductive period, nymphal mortality, adult fecundity, and doubling time of M. persicae populations were monitored on nontransformed potato plants (NT and the four selected DM lines. Compared to NT plants, DM19 did not induce any effect on M. persicae. In contrast, DM7 and DM11 increased nymphal survival by approximately 20%. DM6 and DM11 lines slightly enhanced M. persicae daily fecundity and intrinsic rate of natural increase, leading to a reduction of the doubling time of the populations by 1 day. DM6 did not impact nymphal mortality, whereas with the DM11 almost all the nymphs survived. Potato plants transformed with the mti-2 gene variably affected the life history of M. persicae but did not show any insecticidal effect on the aphid.

  7. The evolution of insecticide resistance in the peach potato aphid, Myzus persicae.

    Science.gov (United States)

    Bass, Chris; Puinean, Alin M; Zimmer, Christoph T; Denholm, Ian; Field, Linda M; Foster, Stephen P; Gutbrod, Oliver; Nauen, Ralf; Slater, Russell; Williamson, Martin S

    2014-08-01

    The peach potato aphid, Myzus persicae is a globally distributed crop pest with a host range of over 400 species including many economically important crop plants. The intensive use of insecticides to control this species over many years has led to populations that are now resistant to several classes of insecticide. Work spanning over 40 years has shown that M. persicae has a remarkable ability to evolve mechanisms that avoid or overcome the toxic effect of insecticides with at least seven independent mechanisms of resistance described in this species to date. The array of novel resistance mechanisms, including several 'first examples', that have evolved in this species represents an important case study for the evolution of insecticide resistance and also rapid adaptive change in insects more generally. In this review we summarise the biochemical and molecular mechanisms underlying resistance in M. persicae and the insights study of this topic has provided on how resistance evolves, the selectivity of insecticides, and the link between resistance and host plant adaptation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. [Use of silicon as inductor of the resistance in potato to Myzus persicae (Sulzer) (Hemiptera: Aphididae)].

    Science.gov (United States)

    Gomes, Flávia B; Moraes, Jair C; dos Santos, Custódio D; Antunes, Cristiana S

    2008-01-01

    The aphid Myzus persicae (Sulzer) is an important pest of potato and causes direct harm, due to the quantity of sap extracted and for being vector of important phytovirus. This work was carried out to evaluate the action of silicon as a resistance inducer of potato to M. persicae. Four treatments were tried: foliar fertilization with silicon acid at 1%; soil fertilization with 250 ml silicic acid solution at 1%; foliar fertilization with silicon acid at 1% + soil fertilization with 250 ml silicic acid solution at 1%; and a control. The treatments were applied thirty days after the explants emergence. Fifteen days after the application of the treatments, feeding preference and some biological aspects of the aphids were evaluated. After, the content of tannins and lignin present in the leaves and the activity of the enzymes peroxidase and phenylalanine ammonia-lyase were also determined. The silicon fertilization did not affect the preference of the aphids; however it reduced fecundity and the rate of population growth of the insects. The lignin percentage increased in the leaves of plants fertilized with silicon via soil and/or foliar and the percentage of tannins increased only in the leaves fertilized via soil plus foliar. The silicon acted as a resistance inducer to M. persicae in potato.

  9. Insecticidal activity of rhamnolipid isolated from pseudomonas sp. EP-3 against green peach aphid (Myzus persicae).

    Science.gov (United States)

    Kim, Seul Ki; Kim, Young Cheol; Lee, Sunwoo; Kim, Jin Cheol; Yun, Mi Young; Kim, In Seon

    2011-02-09

    Microorganisms capable of growth on oils are potential sources of biopesticides, as they produce complex molecules such as biosurfactants and lipopeptides. These molecules have antimicrobial activity against plant pathogens, but few data are available on their insecticidal activity. The present study describes the insecticidal activity of a rhamnolipid isolated from diesel oil-degrading Pseudomonas sp. EP-3 (EP-3). The treatment of cell-free supernatants of EP-3 grown on glucose-mineral medium for 96 h led to > 80% mortality of aphids (Myzus persicae) within 24 h. Bioassay-guided chromatography coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MADLDI-TOF MS) and (¹H, ¹³C) nuclear magnetic resonance (NMR) analyses was employed to isolate and identify the EP-3 insecticidal metabolites. Dirhamnolipid, with molecular formulas of C₃₂H₅₈O₁₃ and C₃₄H₆₂O₁₃, was identified as a main metabolite exhibiting insecticidal activity against aphids. Dirhamnolipid showed a dose-dependent mortality against aphids, producing about 50% mortality at 40 μg/mL and 100% mortality at 100 μg/mL. Microscopy analyses of aphids treated with dirhamnolipid revealed that dirhamnolipid caused insect death by affecting cuticle membranes. This is the first report of rhamnolipid as an insecticidal metabolite against M. persicae. Rhamnolipid shows potential for use as a pesticide to control agricultural pests.

  10. [Geostatistics analysis on spatial patterns of Myzus persicae and Erigonidium graminicola in plum orchard].

    Science.gov (United States)

    Ding, Chengcheng; Zou, Yunding; Bi, Shoudong; Gao, Caiqiu; Liu, Xiaolin; Cao, Cuanwang; Meng, Qinglei; Li, Changgen

    2005-07-01

    Investigations on the spatial construction and distribution of Myzus persicae and Erigonidium graminicola in a plum orchard were conducted from March 2003 to November 2003. The results indicated that the semivariogram of Myzus persicae could be described by spherical model, except on June 27 and November 22, which should be described by lined model, and that of Erigonidium graminicola could be described by spherical model, except on May 21, May 31, October 19 and November 22, which should be described by lined model. It could be concluded that the amount and spatial distribution of Erigonidium graminicola was closely related to those of Myzus persicae.

  11. Molecular and Insecticidal Characterization of a Novel Cry-Related Protein from Bacillus Thuringiensis Toxic against Myzus persicae

    Science.gov (United States)

    Palma, Leopoldo; Muñoz, Delia; Berry, Colin; Murillo, Jesús; Ruiz de Escudero, Iñigo; Caballero, Primitivo

    2014-01-01

    This study describes the insecticidal activity of a novel Bacillus thuringiensis Cry-related protein with a deduced 799 amino acid sequence (~89 kDa) and ~19% pairwise identity to the 95-kDa-aphidicidal protein (sequence number 204) from patent US 8318900 and ~40% pairwise identity to the cancer cell killing Cry proteins (parasporins Cry41Ab1 and Cry41Aa1), respectively. This novel Cry-related protein contained the five conserved amino acid blocks and the three conserved domains commonly found in 3-domain Cry proteins. The protein exhibited toxic activity against the green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae) with the lowest mean lethal concentration (LC50 = 32.7 μg/mL) reported to date for a given Cry protein and this insect species, whereas it had no lethal toxicity against the Lepidoptera of the family Noctuidae Helicoverpa armigera (Hübner), Mamestra brassicae (L.), Spodoptera exigua (Hübner), S. frugiperda (J.E. Smith) and S. littoralis (Boisduval), at concentrations as high as ~3.5 μg/cm2. This novel Cry-related protein may become a promising environmentally friendly tool for the biological control of M. persicae and possibly also for other sap sucking insect pests. PMID:25384108

  12. Molecular and Insecticidal Characterization of a Novel Cry-Related Protein from Bacillus Thuringiensis Toxic against Myzus persicae

    Directory of Open Access Journals (Sweden)

    Leopoldo Palma

    2014-11-01

    Full Text Available This study describes the insecticidal activity of a novel Bacillus thuringiensis Cry-related protein with a deduced 799 amino acid sequence (~89 kDa and ~19% pairwise identity to the 95-kDa-aphidicidal protein (sequence number 204 from patent US 8318900 and ~40% pairwise identity to the cancer cell killing Cry proteins (parasporins Cry41Ab1 and Cry41Aa1, respectively. This novel Cry-related protein contained the five conserved amino acid blocks and the three conserved domains commonly found in 3-domain Cry proteins. The protein exhibited toxic activity against the green peach aphid, Myzus persicae (Sulzer (Homoptera: Aphididae with the lowest mean lethal concentration (LC50 = 32.7 μg/mL reported to date for a given Cry protein and this insect species, whereas it had no lethal toxicity against the Lepidoptera of the family Noctuidae Helicoverpa armigera (Hübner, Mamestra brassicae (L., Spodoptera exigua (Hübner, S. frugiperda (J.E. Smith and S. littoralis (Boisduval, at concentrations as high as ~3.5 μg/cm2. This novel Cry-related protein may become a promising environmentally friendly tool for the biological control of M. persicae and possibly also for other sap sucking insect pests.

  13. Plant extracts in the control of aphids Brevicoryne brassicae (L. and Myzus persicae (SulzerExtratos vegetais no controle dos afídeos Brevicoryne brassicae (L. e Myzus persicae (Sulzer

    Directory of Open Access Journals (Sweden)

    Rafael Reginato Ávila

    2011-07-01

    Full Text Available Were accomplished the effect of plant extracts of clove basil (Ocimum gratissimum L., horsetail (Equisetum hyemale L., coriander (Coriandrum sativum L. and tobacco (Nicotiana tabacum L. on Brevicoryne brassicae (L., 1758 and Myzus persicae (Sulzer, 1776 aphids in cabbage Brassica oleracea (L.. The treatments consisted of plant extracts prepared fresh and dry (concentrations of 2.5; 5.0; and 10% and the controls insecticide acephate and water. These solutions were sprayed on cabbage discs placed on agar in Petri dishes, containing twenty adult aphids. In sequence, the Petri dishes were sealed with plastic film and this procedure was repeated for the two aphid species studied. The assessment of the number of live nymphs and adults occurred at 1, 12, 24, and 72 hours after installation. The extracts of coriander and tobacco prepared in a concentration of 10% showed toxic effects similar to the organophosphate insecticide acephate, on adults and nymphs of the aphids Brevicoryne brassicae and Myzus persicae. Coriander revealed a promising alternative that deserves detailed studies regarding the performance of its active ingredients and dosage determination in order to provide a safe herbal product to control insects.Avaliou-se o efeito de extratos vegetais de alfavaca-cravo (Ocimum gratissimum L., cavalinha (Equisetum hyemale L., coentro (Coriandrum sativum L. e fumo (Nicotiana tabacum L. sobre os pulgões Brevicoryne brassicae (L., 1758 e Myzus persicae (Sulzer, 1776 em couve Brassica oleracea (L.. Os tratamentos consistiram de extratos vegetais preparados a fresco e seco (nas concentrações de 2,5; 5,0 e 10%, do padrão inseticida acefato e de água. As soluções assim obtidas foram pulverizadas em discos de couve colocados sobre agar em placas de Petri, contendo vinte pulgões adultos. Na sequência, as placas de Petri foram vedadas com filme plástico transparente, sendo este procedimento repetido para as duas espécies de afídeos. A avalia

  14. A functional genomics approach identifies candidate effectors from the aphid species Myzus persicae (green peach aphid).

    Science.gov (United States)

    Bos, Jorunn I B; Prince, David; Pitino, Marco; Maffei, Massimo E; Win, Joe; Hogenhout, Saskia A

    2010-11-18

    Aphids are amongst the most devastating sap-feeding insects of plants. Like most plant parasites, aphids require intimate associations with their host plants to gain access to nutrients. Aphid feeding induces responses such as clogging of phloem sieve elements and callose formation, which are suppressed by unknown molecules, probably proteins, in aphid saliva. Therefore, it is likely that aphids, like plant pathogens, deliver proteins (effectors) inside their hosts to modulate host cell processes, suppress plant defenses, and promote infestation. We exploited publicly available aphid salivary gland expressed sequence tags (ESTs) to apply a functional genomics approach for identification of candidate effectors from Myzus persicae (green peach aphid), based on common features of plant pathogen effectors. A total of 48 effector candidates were identified, cloned, and subjected to transient overexpression in Nicotiana benthamiana to assay for elicitation of a phenotype, suppression of the Pathogen-Associated Molecular Pattern (PAMP)-mediated oxidative burst, and effects on aphid reproductive performance. We identified one candidate effector, Mp10, which specifically induced chlorosis and local cell death in N. benthamiana and conferred avirulence to recombinant Potato virus X (PVX) expressing Mp10, PVX-Mp10, in N. tabacum, indicating that this protein may trigger plant defenses. The ubiquitin-ligase associated protein SGT1 was required for the Mp10-mediated chlorosis response in N. benthamiana. Mp10 also suppressed the oxidative burst induced by flg22, but not by chitin. Aphid fecundity assays revealed that in planta overexpression of Mp10 and Mp42 reduced aphid fecundity, whereas another effector candidate, MpC002, enhanced aphid fecundity. Thus, these results suggest that, although Mp10 suppresses flg22-triggered immunity, it triggers a defense response, resulting in an overall decrease in aphid performance in the fecundity assays. Overall, we identified aphid

  15. Inferring the population structure of Myzus persicae in diverse agroecosystems using microsatellite markers.

    Science.gov (United States)

    Sanchez, Juan Antonio; La-Spina, Michelangelo; Guirao, Pedro; Cánovas, Fernando

    2013-08-01

    Diverse agroecosystems offer phytophagous insects a wide choice of host plants. Myzus persicae is a polyphagous aphid common in moderate climates. During its life cycle it alternates between primary and secondary hosts. A spatial genetic population structure may arise due to environmental factors and reproduction modes. The aim of this work was to determine the spatial and temporal genetic population structure of M. persicae in relation to host plants and climatic conditions. For this, 923 individuals of M. persicae collected from six plant families between 2005 and 2008 in south-eastern Spain were genotyped for eight microsatellite loci. The population structure was inferred by neighbour-joining, analysis of molecular variance (AMOVA) and Bayesian analyses. Moderate polymorphism was observed for the eight loci in almost all the samples. No differences in the number of alleles were observed between primary and secondary hosts or between geographical areas. The proportion of unique genotypes found in the primary host was similar in the north (0.961 ± 0.036) and the south (0.987 ± 0.013), while in the secondary host it was higher in the north (0.801 ± 0.159) than in the south (0.318 ± 0.063). Heterozygosity excess and linkage disequilibrium suggest a high representation of obligate parthenogens in areas with warmer climate and in the secondary hosts. The F ST-values pointed to no genetic differentiation of M. persicae on the different plant families. F ST-values, AMOVA and Bayesian model-based cluster analyses pointed to a significant population structure that was related to primary and secondary hosts. Differences between primary and secondary hosts could be due to the overrepresentation of parthenogens on herbaceous plants.

  16. Use of silicon as inductor of the resistance in potato to Myzus persicae (Sulzer) (Hemiptera: Aphididae); Uso de silicio como indutor de resistencia em batata a Myzus persicae (Sulzer) (Hemiptera: Aphididae)

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Flavia B.; Moraes, Jair C.; Antunes, Cristiana [Universidade Federal de Lavras, MG (Brazil). Dept. de Entomologia; Santos, Custodio D. dos [Universidade Federal de Lavras, MG (Brazil). Dept. de Quimica

    2008-03-15

    The aphid Myzus persicae (Sulzer) is an important pest of potato and causes direct harm, due to the quantity of sap extracted and for being vector of important phytovirus. This work was carried out to evaluate the action of silicon as a resistance inducer of potato to M. persicae. Four treatments were tried: foliar fertilization with silicon acid at 1%; soil fertilization with 250 ml silicic acid solution at 1%; foliar fertilization with silicon acid at 1% + soil fertilization with 250 ml silicic acid solution at 1%; and a control. The treatments were applied thirty days after the explants emergence. Fifteen days after the application of the treatments, feeding preference and some biological aspects of the aphids were evaluated. After, the content of tannins and lignin present in the leaves and the activity of the enzymes peroxidase and phenylalanine ammonia-lyase were also determined. The silicon fertilization did not affect the preference of the aphids; however it reduced fecundity and the rate of population growth of the insects. The lignin percentage increased in the leaves of plants fertilized with silicon via soil and/or foliar and the percentage of tannins increased only in the leaves fertilized via soil plus foliar. The silicon acted as a resistance inducer to M. persicae in potato. (author)

  17. Infection of host plants by Cucumber mosaic virus increases the susceptibility of Myzus persicae aphids to the parasitoid Aphidius colemani.

    Science.gov (United States)

    Mauck, Kerry E; De Moraes, Consuelo M; Mescher, Mark C

    2015-06-04

    Plant viruses can profoundly alter the phenotypes of their host plants, with potentially far-reaching implications for ecology. Yet few studies have explored the indirect, host-mediated, effects of plant viruses on non-vector insects. We examined how infection of Cucurbita pepo plants by Cucumber mosaic virus (CMV) impacted the susceptibility of aphids (Myzus persicae) to attack by the parasitoid wasp Aphidius colemani. In semi-natural foraging assays, we observed higher rates of aphid parasitism on infected plants compared to healthy plants. Subsequent experiments revealed that this difference is not explained by different attack rates on plants differing in infection status, but rather by the fact that parasitoid larvae successfully complete their development more often when aphid hosts feed on infected plants. This suggests that the reduced nutritional quality of infected plants as host for aphids--documented in previous studies--compromises their ability to mount effective defenses against parasitism. Furthermore, our current findings indicate that the aphid diet during parasitoid development (rather than prior to wasp oviposition) is a key factor influencing resistance. These findings complement our previous work showing that CMV-induced changes in host plant chemistry alter patterns of aphid recruitment and dispersal in ways conducive to virus transmission.

  18. Elevated CO2 impacts bell pepper growth with consequences to Myzus persicae life history, feeding behaviour and virus transmission ability

    Science.gov (United States)

    Dáder, Beatriz; Fereres, Alberto; Moreno, Aránzazu; Trębicki, Piotr

    2016-01-01

    Increasing atmospheric carbon dioxide (CO2) impacts plant growth and metabolism. Indirectly, the performance and feeding of insects is affected by plant nutritional quality and resistance traits. Life history and feeding behaviour of Myzus persicae were studied on pepper plants under ambient (aCO2, 400 ppm) or elevated CO2 (eCO2, 650 ppm), as well as the direct impact on plant growth and leaf chemistry. Plant parameters were significantly altered by eCO2 with a negative impact on aphid’s life history. Their pre-reproductive period was 11% longer and fecundity decreased by 37%. Peppers fixed significantly less nitrogen, which explains the poor aphid performance. Plants were taller and had higher biomass and canopy temperature. There was decreased aphid salivation into sieve elements, but no differences in phloem ingestion, indicating that the diminished fitness could be due to poorer tissue quality and unfavourable C:N balance, and that eCO2 was not a factor impeding feeding. Aphid ability to transmit Cucumber mosaic virus (CMV) was studied by exposing source and receptor plants to ambient (427 ppm) or elevated (612 ppm) CO2 before or after virus inoculation. A two-fold decrease on transmission was observed when receptor plants were exposed to eCO2 before aphid inoculation when compared to aCO2.

  19. Mp10 and Mp42 from the aphid species Myzus persicae trigger plant defenses in Nicotiana benthamiana through different activities.

    Science.gov (United States)

    Rodriguez, Patricia A; Stam, Remco; Warbroek, Tim; Bos, Jorunn I B

    2014-01-01

    Aphids are phloem-feeding insects that, like other plant parasites, deliver effectors inside their host to manipulate host responses. The Myzus persicae (green peach aphid) candidate effectors Mp10 and Mp42 were previously found to reduce aphid fecundity upon intracellular transient overexpression in Nicotiana benthamiana. We performed functional analyses of these proteins to investigate whether they activate defenses through similar activities. We employed a range of functional characterization experiments based on intracellular transient overexpression in N. benthamiana to determine the subcellular localization of Mp10 and Mp42 and investigate their role in activating plant defense signaling. Mp10 and Mp42 showed distinct subcellular localization in planta, suggesting that they target different host compartments. Also, Mp10 reduced the levels of Agrobacterium-mediated overexpression of proteins. This reduction was not due to an effect on Agrobacterium viability. Transient overexpression of Mp10 but not Mp42 activated jasmonic acid and salicylic acid signaling pathways and decreased susceptibility to the hemibiotrophic plant pathogen Phytophthora capsici. We found that two candidate effectors from the broad-host-range aphid M. persicae can trigger aphid defenses through different mechanisms. Importantly, we found that some (candidate) effectors such as Mp10 interfere with Agrobacterium-based overexpression assays, an important tool to study effector activity and function.

  20. Effects of Transgenic Tobacco Plants Expressing ACA Gene from Amaranthus caudatus on the Population Development of Myzus persicae

    Institute of Scientific and Technical Information of China (English)

    GUOHong-Nian; JIAYan-Tao; ZHOUYong-Gang; ZHANGZhen-Shan; OUYANGQing; JIANGYing; TIANYing-Chuan

    2004-01-01

    To investigate the possible function of the agglutinin from Amaranthus caudatus L. (ACA) in plant defending against insect pests, ACA cDNA was cloned by RT-PCR and the 5' and 3' sequences were confirmed by rapid amplification of cDNA ends (RACE). The phloem-specific expression vector of ACA gene, pBCACAc, was constructed based on the plant binary vector pBC438 and transfered into tobacco plants via Agrobacterium-mediated transformation method. Results from PCR and Southern blotting analysis showed that AOA gene was integrated into the genomes of transformed plants and the transgene integration varied from one to four estimated copies per genome. Western blotting analysis indicated that ACA gene was transcribed and translated in the transgenic plants. The bioassay of Myzus persicae Sulzer on detached leaves demonstrated that the 78% transgenic tobacco plants displayed an average aphid-resistant rate of more than 75%. Some apterous progeny of M. persicae were found dead on the resistant plants. These results indicate that ACA gene should be an effective aphid-resistant gene and could be valuable for application in crop breeding for aphid resistance.

  1. Observing Insects.

    Science.gov (United States)

    Arbel, Ilil

    1991-01-01

    Describes how to observe and study the fascinating world of insects in public parks, backyards, and gardens. Discusses the activities and habits of several common insects. Includes addresses for sources of beneficial insects, seeds, and plants. (nine references) (JJK)

  2. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Myzus persicae

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the green peach aphid, Myzus persicae, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures t...

  3. Acquisition and transmission of potato leafroll virus by Myzus persicae; quantitative aspects.

    NARCIS (Netherlands)

    Heuvel, van den J.F.J.M.

    1991-01-01

    Studying the transmission of potato leafroll virus (PLRV) by Myzus persicae from infected Physalis floridana plants, revealed that the ability of aphids to transmit the virus differed widely among individuals and strongly depended on the biotype of the vector aphid and the age of the virus source. V

  4. The site of potato leafroll virus multiplication in its vector, Myzus persicae : an anatomical study

    NARCIS (Netherlands)

    Ponsen, M.B.

    1972-01-01

    In search of the site of PLRV multiplication in its vector a detailed study was made of the anatomy of the aphid, Myzus persicae SULZ. The findings are summarized in the following lines:Alimentary canalThe most anterior part of the alimentary canal is the food canal which is firmly interlocked by th

  5. The site of potato leafroll virus multiplication in its vector, Myzus persicae : an anatomical study

    NARCIS (Netherlands)

    Ponsen, M.B.

    1972-01-01

    In search of the site of PLRV multiplication in its vector a detailed study was made of the anatomy of the aphid, Myzus persicae SULZ. The findings are summarized in the following lines:

    Alimentary canal

    The most anterior part of

  6. Influence of Silicon on Resistance of Zinnia Elegans to Myzus Persicae (Hemiptera: Aphididae)

    Science.gov (United States)

    Studies were conducted to examine the effect of treating Zinnia elegans Jacq. with soluble silicon on the performance of the green peach aphid, Myzus persicae (Sulzer). Zinnia elegans plants were irrigated every 2 days throughout the duration of the experiment with a nutrient solution amended with ...

  7. A New SAS program for behavioral analysis of electrical penetration graph data

    Science.gov (United States)

    Monitoring feeding behaviors of insects whose piercing-sucking mouthparts are inserted into plant tissue is done by making the insect part of an electronic circuit, using electropenetrography (EPG). Fluctuating voltage signals in the circuit are graphed, and resulting waveforms are interpreted as sp...

  8. Waveform library for chinch bugs (Hemiptera: Heteroptera: Blissidae): Characterization of Electrical Penetration Graph (EPG) waveforms at multiple input impedances

    Science.gov (United States)

    Electrical penetration graph (EPG) monitoring has been used extensively to elucidate mechanisms of resistance in plants to insect herbivores with piercing-sucking mouthparts, or stylets. Characterization of waveforms produced by insects during stylet probing is essential to the application of this ...

  9. Unexpected effects of chitinases on the peach-potato aphid (Myzus persicae Sulzer) when delivered via transgenic potato plants (Solanum tuberosum Linné) and in vitro.

    Science.gov (United States)

    Saguez, Julien; Hainez, Romaric; Cherqui, Anas; Van Wuytswinkel, Olivier; Jeanpierre, Haude; Lebon, Gaël; Noiraud, Nathalie; Beaujean, Antony; Jouanin, Lise; Laberche, Jean-Claude; Vincent, Charles; Giordanengo, Philippe

    2005-02-01

    With the aim of producing insect-resistant potato plants, internode explants of Solanum tuberosum L. cv. Désirée were transformed with an Agrobacterium strain C58pMP90 containing an insect (Phaedon cochleariae: Coleoptera, Chrysomelidae) chitinase gene and the neomycin phosphotransferase (nptII) gene as selectable marker, both under the control of the viral CaMV 35S promoter. Three transformed potato lines (CH3, CH5 and CH25) exhibiting the highest chitinolytic activities were selected for feeding experiments with the peach-potato aphid, Myzus persicae (Sulzer), under controlled photoperiod and temperature conditions. Aphids fed on transgenic potato plants showed a reduced pre-reproductive period and an enhanced daily fecundity. Transgenic potato lines did not affect nymphal mortality, but improved several biological parameters related to aphid population's growth. Artificial diets were used to provide active (1, 10, 100 and 500 microg ml(-1)) and inactive (500 microg ml(-1)) bacterial (Serratia marcescens) chitinase to M. persicae. These compounds increased nymph survival at all active chitinase doses when compared to the control diet, while inactive chitinase did not. Although the pre-reproductive period was slightly shortened and the daily fecundity slightly higher, active and inactive chitinase provided as food led a reduction from 1 to 1.5 day population's doubling time. Therefore chitinase activity was responsible for the probiotic effects on aphids. Our results question the relevance of a chitinase-based strategy in the context of potato culture protection.

  10. Edible Insects

    NARCIS (Netherlands)

    Huis, van A.; Dunkel, F.V.

    2016-01-01

    The interest in insects as human food in the Western world is increasingly considered as a viable alternative to other protein sources. In tropical countries it is common practice and about 2000 insect species are eaten. Insects emit low levels of greenhouse gases, need little water, and require

  11. Amplification of a cytochrome P450 gene is associated with resistance to neonicotinoid insecticides in the aphid Myzus persicae.

    Directory of Open Access Journals (Sweden)

    Alin M Puinean

    2010-06-01

    Full Text Available The aphid Myzus persicae is a globally significant crop pest that has evolved high levels of resistance to almost all classes of insecticide. To date, the neonicotinoids, an economically important class of insecticides that target nicotinic acetylcholine receptors (nAChRs, have remained an effective control measure; however, recent reports of resistance in M. persicae represent a threat to the long-term efficacy of this chemical class. In this study, the mechanisms underlying resistance to the neonicotinoid insecticides were investigated using biological, biochemical, and genomic approaches. Bioassays on a resistant M. persicae clone (5191A suggested that P450-mediated detoxification plays a primary role in resistance, although additional mechanism(s may also contribute. Microarray analysis, using an array populated with probes corresponding to all known detoxification genes in M. persicae, revealed constitutive over-expression (22-fold of a single P450 gene (CYP6CY3; and quantitative PCR showed that the over-expression is due, at least in part, to gene amplification. This is the first report of a P450 gene amplification event associated with insecticide resistance in an agriculturally important insect pest. The microarray analysis also showed over-expression of several gene sequences that encode cuticular proteins (2-16-fold, and artificial feeding assays and in vivo penetration assays using radiolabeled insecticide provided direct evidence of a role for reduced cuticular penetration in neonicotinoid resistance. Conversely, receptor radioligand binding studies and nucleotide sequencing of nAChR subunit genes suggest that target-site changes are unlikely to contribute to resistance to neonicotinoid insecticides in M. persicae.

  12. Transcriptome Analysis of Green Peach Aphid (Myzus persicae): Insight into Developmental Regulation and Inter-Species Divergence

    Science.gov (United States)

    Ji, Rui; Wang, Yujun; Cheng, Yanbin; Zhang, Meiping; Zhang, Hong-Bin; Zhu, Li; Fang, Jichao; Zhu-Salzman, Keyan

    2016-01-01

    Green peach aphid (Myzus persicae) and pea aphid (Acyrthosiphon pisum) are two phylogenetically closely related agricultural pests. While pea aphid is restricted to Fabaceae, green peach aphid feeds on hundreds of plant species from more than 40 families. Transcriptome comparison could shed light on the genetic factors underlying the difference in host range between the two species. Furthermore, a large scale study contrasting gene expression between immature nymphs and fully developed adult aphids would fill a previous knowledge gap. Here, we obtained transcriptomic sequences of green peach aphid nymphs and adults, respectively, using Illumina sequencing technology. A total of 2244 genes were found to be differentially expressed between the two developmental stages, many of which were associated with detoxification, hormone production, cuticle formation, metabolism, food digestion, and absorption. When searched against publically available pea aphid mRNA sequences, 13,752 unigenes were found to have no homologous counterparts. Interestingly, many of these unigenes that could be annotated in other databases were involved in the “xenobiotics biodegradation and metabolism” pathway, suggesting the two aphids differ in their adaptation to secondary metabolites of host plants. Conversely, 3989 orthologous gene pairs between the two species were subjected to calculations of synonymous and nonsynonymous substitutions, and 148 of the genes potentially evolved in response to positive selection. Some of these genes were predicted to be associated with insect-plant interactions. Our study has revealed certain molecular events related to aphid development, and provided some insight into biological variations in two aphid species, possibly as a result of host plant adaptation.

  13. Transcriptome analysis of green peach aphid (Myzus persicae: Insight into developmental regulation and inter-species divergence

    Directory of Open Access Journals (Sweden)

    Rui Ji

    2016-10-01

    Full Text Available Green peach aphid (Myzus persicae and pea aphid (Acyrthosiphon pisum are two phylogenetically closely related agricultural pests. While pea aphid is restricted to Fabaceae, green peach aphid feeds on hundreds of plant species from more than 40 families. Transcriptome comparison could shed light on the genetic factors underlying the difference in host range between the two species. Furthermore, a large scale study contrasting gene expression between immature nymphs and fully developed adult aphids would fill a previous knowledge gap. Here, we obtained transcriptomic sequences of green peach aphid nymphs and adults, respectively, using Illumina sequencing technology. A total of 2,244 genes were found to be differentially expressed between the two developmental stages, many of which were associated with detoxification, hormone production, cuticle formation, metabolism, food digestion and absorption. When searched against publically available pea aphid mRNA sequences, 13,752 unigenes were found to have no homologous counterparts. Interestingly, many of these unigenes that could be annotated in other databases were involved in the xenobiotics biodegradation and metabolism pathway, suggesting the two aphids differ in their adaptation to secondary metabolites of host plants. Conversely, 3,989 orthologous gene pairs between the two species were subjected to calculations of synonymous and nonsynonymous substitutions, and 148 of the genes potentially evolved in response to positive selection. Some of these genes were predicted to be associated with insect-plant interactions. Our study has revealed certain molecular events related to aphid development, and provided some insight into biological variations in two aphid species, possibly as a result of host plant adaptation.

  14. Effect of Colored Sticky Cards on Non-target Insects

    Institute of Scientific and Technical Information of China (English)

    Zhen CHEN; Yihang GE; Xia LIU; Rongping KUANG

    2015-01-01

    Field experiments to evaluate four different colored sticky cards for trap-ping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yel ow, blue, green, and red sticky cards were used to trap insects in the field. The total number of insects species caught was 54, with 3,862 individu-als recorded. Over half of the specimens caught were non-target insects, including phytophagous insects, particularly dipteran species (including many mosquitoes) (50.3%), fol owed by target pests (37.0%), and beneficial insects (12.7%). Statistical analysis revealed a significant difference in attraction to target pests, non-target pests, and beneficial insects among treatment groups. The results showed that higher numbers of target pests (Myzus persicae Sulzer, Empoasca flavescens Fabricius, Nysius ericaecshinly Schil ing) were caught on yel ow sticky card traps compared with blue, green, or red sticky card traps, indicating that yel ow was the best trap color for target pests, with green and blue being progressively less attrac-tive. For non-target insects, including phytophagous insects, flies, and mosquitoes, higher numbers of were caught on blue sticky card traps compared with yel ow, green, or red sticky card traps. Our study indicated that blue was the most attrac-tive color for flies, especial y for the housefly, Musca domestica Linnaeus. Our study also showed that most beneficial insects exhibited preferences to particular trap col-or characteristics: yel ow was the most attractive color for parasitic wasps and lady beetles; blue was the most attractive color for hoverflies and honeybees. In contrast, green and red had no significant attraction to beneficial insects.

  15. Insect Antifeedant Potential of Xanthohumol, Isoxanthohumol, and Their Derivatives.

    Science.gov (United States)

    Stompor, Monika; Dancewicz, Katarzyna; Gabryś, Beata; Anioł, Mirosław

    2015-08-05

    Xanthohumol (14) and isoxanthohumol (6) derived from hop (Humulus lupulus L., Cannabaceae) and selected chalcone and chromene derivatives, obtained by chemical synthesis, were studied for antifeedant activity against the peach-potato aphid (Myzus persicae [Sulz.]). The study used also commercially available 4-chromanone (1), flavanone (4), naringenin (5), chromone (7), flavone (8), 7-aminoflavone (9), trans-chalcone (10), and 4-methoxychalcone (12). For chromone derivatives it was observed that the presence of a phenyl substituent at C-2 in the chromone (7) skeleton increased the insect antifeedant activity, and this activity was observed for a longer time. Also, the introduction of an amino group at C-7 of flavone (8) considerably increased the insect antifeedant activity, which was observed for the whole test time. Among the compounds examined, the strongest deterrents were isoxanthohumol (6), 7-methoxy-2,2-dimethylchroman-4-one (3), 7-aminoflavone (9), and 4-ethyl-4'-methoxychalcone (13).

  16. Intercropping System for Protection the Potato Plant from Insect Infestation

    Directory of Open Access Journals (Sweden)

    Aziza Sharaby

    2015-06-01

    Full Text Available The use of intercropping system provides an option for insect control for organic farmers that are limited in their chemical use. Additionally, intercropping systems can be attractive to conventional growers as a cost-effective insect control solution. A study was carried out for two seasons 2011-2012 and 2012-2013 to evaluate the effect of intercropping of potato (Solanum tuberosum L. with onion (Allium cepa L. on whitefly (Bemicia tabasi Gennadius and aphids’ Myzus persicae Sulz. and Aphis gossypii Glover infestation in potato fields. Results indicated that intercropping significantly reduced potato plant infestation with whitefly by 42.7, 51.3% while it was 62.69% reduction with aphids during the two successive winter seasons than when potato plants were cultivated alone. Therefore, intercropping could be recommended as a protection method of reducing pest population in the fields.

  17. Eating insects

    NARCIS (Netherlands)

    Tan, Hui Shan Grace

    2017-01-01

    In recent years, edible insects have gained global attention due to their nutritional and environmental advantages over conventional meat. While numerous species of edible insects are enjoyed in various cultures around the world, most Western consumers react with disgust and aversion towards eating

  18. Insect Keepers

    Science.gov (United States)

    Moore, Virginia J.; Chessin, Debby A.; Theobald, Becky

    2010-01-01

    Insects are fascinating creatures--especially when you and your students get up close and personal with them! To that end, the authors facilitated an inquiry-based investigation with an emphasis on identification of the different types of insects found in the school yard, their characteristics, their habitat, and what they eat, while engaging the…

  19. Insect phylogenomics.

    Science.gov (United States)

    Behura, S K

    2015-08-01

    Phylogenomics, the integration of phylogenetics with genome data, has emerged as a powerful approach to study the evolution and systematics of species. Recently, several studies employing phylogenomic tools have provided better insights into insect evolution. Next-generation sequencing methods are now increasingly used by entomologists to generate genomic and transcript sequences of various insect species and strains. These data provide opportunities for comparative genomics and large-scale multigene phylogenies of diverse lineages of insects. Phy-logenomic investigations help us to better understand systematic and evolutionary relationships of insect species that play important roles as herbivores, predators, detritivores, pollinators and disease vectors. It is important that we critically assess the prospects and limitations of phylogenomic methods. In this review, I describe the current status, outline the major challenges and remark on potential future applications of phylogenomic tools in studying insect systematics and evolution.

  20. History, principles, and summary of applications of electropenetrography (EPG)

    Science.gov (United States)

    Studying feeding, plant damage, and transmission (i.e. acquisition, retention, and inoculation) of plant pathogens by hemipteran insect pests is challenging. Hemipteran piercing-sucking mouthparts, the stylets, are probed into opaque plant tissues precluding direct observation. This challenge was ov...

  1. Insertion site selection and feeding of the hemlock woolly adelgid: implications for host-plant resistance

    Science.gov (United States)

    K.L.F. Oten; A.C. Cohen; F.P. Hain

    2012-01-01

    The hemlock woolly adelgid (HWA), Adelges tsugae (Hemiptera: Adelgidae), is an invasive forest pest that threatens the existence of eastern hemlock (Tsuga canadensis (L.) Carr.) and Carolina hemlock (T. caroliniana Engelm.) in the eastern United States. It is a small, aphid like insect with piercing-sucking...

  2. The Sharpshooter X-wave: Correlation of an Electrical Penetration Graph (EPG) Waveform with Xylem Penetration During Feeding of Glassy-winged Sharpshooter

    Science.gov (United States)

    Electrical penetration graph (EPG) monitoring is a rigorous means of observing and quantifying the feeding of any piercing-sucking insect. Previous studies with aphid and leafhopper pests of agricultural crops have demonstrated the unique value of what is termed the X wave, i.e. the waveform that r...

  3. The Sharpshooter X-wave: Correlation of xylem penetration by glassy-winged sharpshooter with an electrical penetration graph (EPG) waveform

    Science.gov (United States)

    Electrical penetration graph (EPG) monitoring is a rigorous means of observing and quantifying the feeding of any piercing-sucking insect. Previous studies with aphid and leafhopper pests of agricultural crops have demonstrated the unique value of what is termed the X wave, i.e. the waveform that r...

  4. Sharpshooter X-wave: Correlation of an Electrical Penetration Graph (EPG) Waveform With Xylem Penetration Supports a Hypothesized Mechanism For Xylella Fastidiosa Inoculation

    Science.gov (United States)

    Electrical Penetration Graph (EPG) monitoring is the most rigorous means of observation and quantification of feeding by piercing-sucking arthropods. Previous EPG studies with aphids and leafhoppers have demonstrated that the X waveform identifies when the insect is ingesting from its preferred pla...

  5. Transmission of the opportunistic cotton (Gossypium hirsutum L.) boll pathogen Pantoea agglomerans by the brown stink bug (Euschistus servus Say)

    Science.gov (United States)

    Damage to developing cotton bolls by piercing-sucking insects such as stink bugs has traditionally been attributed solely to pest feeding. Previously, we showed clear differences in severity of boll damage resulting from southern green stink bug (Nezara viridula L.) fed sterile food compared to thos...

  6. Improvement of Markov Chain Model for Occurrence Degree Prediction of Myzus persicae (Sulzer) and Its Application

    Institute of Scientific and Technical Information of China (English)

    REN Guangwei; WANG Xiufang; WANG Xinwei; ZHOU Xiansheng; DONG Xiaowei

    2008-01-01

    For long-term prediction of occurrence degree of tobacco aphid Myzus persicae (Sulzer), Markov chain method was used to establish prediction model for occurrence degree of tobacco aphid. With 4 levels of occurrence degree, Markov chain model was established based on the data in 1987-2004. The results indicated that the accuracy for total prediction in 2005-2007 and the back prediction in 1987-2004 reached 88.89% and 85.12%, respectively. The method is simple and feasible for long-term prediction of occurrence degree of tobacco aphid.

  7. The NIa-Pro protein of Turnip mosaic virus improves growth and reproduction of the aphid vector, Myzus persicae (green peach aphid).

    Science.gov (United States)

    Casteel, Clare L; Yang, Chunling; Nanduri, Ananya C; De Jong, Hannah N; Whitham, Steven A; Jander, Georg

    2014-02-01

    Many plant viruses depend on aphids and other phloem-feeding insects for transmission within and among host plants. Thus, viruses may promote their own transmission by manipulating plant physiology to attract aphids and increase aphid reproduction. Consistent with this hypothesis, Myzus persicae (green peach aphids) prefer to settle on Nicotiana benthamiana infected with Turnip mosaic virus (TuMV) and fecundity on virus-infected N. benthamiana and Arabidopsis thaliana (Arabidopsis) is higher than on uninfected controls. TuMV infection suppresses callose deposition, an important plant defense, and increases the amount of free amino acids, the major source of nitrogen for aphids. To investigate the underlying molecular mechanisms of this phenomenon, 10 TuMV genes were over-expressed in plants to determine their effects on aphid reproduction. Production of a single TuMV protein, nuclear inclusion a-protease domain (NIa-Pro), increased M. persicae reproduction on both N. benthamiana and Arabidopsis. Similar to the effects that are observed during TuMV infection, NIa-Pro expression alone increased aphid arrestment, suppressed callose deposition and increased the abundance of free amino acids. Together, these results suggest a function for the TuMV NIa-Pro protein in manipulating the physiology of host plants. By attracting aphid vectors and promoting their reproduction, TuMV may influence plant-aphid interactions to promote its own transmission. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  8. Phenotypic plasticity of Myzus persicae (Hemíptera: Aphididae raised on Brassica oleracea L. var. acephala (kale and Raphanus sativus L. (radish

    Directory of Open Access Journals (Sweden)

    Peppe Fernanda Borja

    2003-01-01

    Full Text Available The study of variability generated by phenotypic plasticity is crucial for predicting evolutionary patterns in insect-plant systems. Given sufficient variation for plasticity, host race formation can be favored and maintained, even simpatrically. The plasticity of size and performance (assessed by the lifetime fitness index r m of six clones of Myzus persicae was tested, with replicates allowed to develop on two hosts, kale (Brassica oleracea var. acephala and radish (Raphanus sativus. The clones showed significant variability in their plasticity. Reaction norms varied through generations and negative genetic correlation, although not significant, tend to increase with the duration of host use. The lack of plasticity in lifetime fitness among generalist clones occurred as an after-effect of the highly plastic determinants. Significant morphological plasticity in host used was observed, but no variation in the plastic responses (GxE interaction was detected. Strong selection for a larger size occurred among individuals reared on radish, the most unfavorable host. Morphological plasticity in general body size (in a multivariate sense was not linear related to fitness plasticity. These observations suggest that a high potential for the evolution of host divergence favors host race formation.

  9. Pathogenicity of conidia-based preparations of entomopathogenic fungi against the greenhouse pest aphids Myzus persicae, Aphis gossypii, and Aulacorthum solani (Hemiptera: Aphididae).

    Science.gov (United States)

    Jandricic, S E; Filotas, M; Sanderson, J P; Wraight, S P

    2014-05-01

    Seeking new isolates of entomopathogenic fungi with greater virulence against greenhouse aphid pests than those currently registered in North America for control of these insects, single-dose screening assays of 44 selected fungal isolates and 4 commercially available strains were conducted against first-instar nymphs of Myzus persicae and Aphis gossypii. The assays identified a number of Beauveria and Metarhizium isolates with virulence equal to or greater than that of the commercial strains against the nymphal aphids, but none exhibited exceptionally high virulence. Virulence of Isaria isolates was unexpectedly low (1000conidia/mm(2)). In dose-response assays, Beauveria ARSEF 5493 proved most virulent against M. persicae and A. gossypii; however, LC50s of this isolate did not differ significantly from those of B. bassiana commercial strain JW-1. Dose-response assays were also conducted with Aulacorthum solani, the first reported evaluations of Beauveria and Metarhizium against this pest. The novel isolate Metarhizium 5471 showed virulence⩾that of Beauveria 5493 in terms of LC25 and LC50, but 5493 produced a steeper dose response (slope). Additional tests showed that adult aphids are more susceptible than nymphs to fungal infection but confirmed that infection has a limited pre-mortem effect on aphid reproduction. Effects of assay techniques and the potential of fungal pathogens as aphid-control agents are discussed.

  10. Enhanced methanol production in plants provides broad spectrum insect resistance.

    Directory of Open Access Journals (Sweden)

    Sameer Dixit

    Full Text Available Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR and spectra showed up to 16 fold higher methanol as compared to control wild type (WT plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid and Bemisia tabaci (whitefly, respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

  11. Insect Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature and environment derived from beetle and other insect fossils. Parameter keywords describe what was measured in this data set. Additional...

  12. Rice-straw mulch reduces the green peach aphid, Myzus persicae (Hemiptera: Aphididae) populations on kale, Brassica oleracea var. acephala (Brassicaceae) plants.

    Science.gov (United States)

    Silva-Filho, Reinildes; Santos, Ricardo Henrique Silva; Tavares, Wagner de Souza; Leite, Germano Leão Demolin; Wilcken, Carlos Frederico; Serrão, José Eduardo; Zanuncio, José Cola

    2014-01-01

    Organic mulches, like peel and rice-straw, besides other materials affect the UV and temperature, which cause a reduction in the aphid arrival. The aim was to evaluate the effect of covering the soil with straw on the populations of the green peach aphid, Myzus persicae on the kale, Brassica oleracea var. acephala plants. The first experiment evaluated the direct effect of the rice-straw mulch and the second its indirect effect on aphid immigration, testing the plant characteristics that could lead to the landing preference of this insect. The third experiment evaluated the direct effect of the mulch on the aphid population. In the second and third experiments, four plants, each in a 14 L polyethylene pot with holes at the bottom, were used in areas with and without soil mulching. These pots were changed between areas, after seven days, to evaluate the effects of this change on the arrival of the winged aphids to the plants. Each plant was covered with anti-aphid gauze and inoculated with one winged M. persicae. Winged and apterous adults of this insect were counted per plant after 15 days. The temperature increased in the mulched plots to a maximum of 21-36°C and to 18-32°C in the plots with or without soil covering, respectively. Plant growth reduced the numbers of the winged aphids landing before and after they were moved to the bare soil plots. The nutrient content was similar in plants in both the mulched and no mulched plots. The population growth of M. persicae was higher in the control than in the mulched plots. This was partially due to temperatures close to 30°C in these plots and changes in the plant physiology. The soil mulching with rice-straw decreased the M. persicae landing, increased the plot temperatures and improved the vegetative growth of the kale plants.

  13. Rice-straw mulch reduces the green peach aphid, Myzus persicae (Hemiptera: Aphididae populations on kale, Brassica oleracea var. acephala (Brassicaceae plants.

    Directory of Open Access Journals (Sweden)

    Reinildes Silva-Filho

    Full Text Available Organic mulches, like peel and rice-straw, besides other materials affect the UV and temperature, which cause a reduction in the aphid arrival. The aim was to evaluate the effect of covering the soil with straw on the populations of the green peach aphid, Myzus persicae on the kale, Brassica oleracea var. acephala plants. The first experiment evaluated the direct effect of the rice-straw mulch and the second its indirect effect on aphid immigration, testing the plant characteristics that could lead to the landing preference of this insect. The third experiment evaluated the direct effect of the mulch on the aphid population. In the second and third experiments, four plants, each in a 14 L polyethylene pot with holes at the bottom, were used in areas with and without soil mulching. These pots were changed between areas, after seven days, to evaluate the effects of this change on the arrival of the winged aphids to the plants. Each plant was covered with anti-aphid gauze and inoculated with one winged M. persicae. Winged and apterous adults of this insect were counted per plant after 15 days. The temperature increased in the mulched plots to a maximum of 21-36°C and to 18-32°C in the plots with or without soil covering, respectively. Plant growth reduced the numbers of the winged aphids landing before and after they were moved to the bare soil plots. The nutrient content was similar in plants in both the mulched and no mulched plots. The population growth of M. persicae was higher in the control than in the mulched plots. This was partially due to temperatures close to 30°C in these plots and changes in the plant physiology. The soil mulching with rice-straw decreased the M. persicae landing, increased the plot temperatures and improved the vegetative growth of the kale plants.

  14. Insecticidal spider venom toxin fused to snowdrop lectin is toxic to the peach-potato aphid, Myzus persicae (Hemiptera: Aphididae) and the rice brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae).

    Science.gov (United States)

    Down, Rachel E; Fitches, Elaine C; Wiles, Duncan P; Corti, Paola; Bell, Howard A; Gatehouse, John A; Edwards, John P

    2006-01-01

    The SFI1/GNA fusion protein, comprising of snowdrop lectin (Galanthus nivalis agglutinin, GNA) fused to an insecticidal spider venom neurotoxin (Segestria florentina toxin 1, SFI1) was tested for toxicity against the rice brown planthopper Nilaparvata lugens (Stål) and the peach-potato aphid Myzus persicae (Sulzer) by incorporation into artificial diets. Significant effects on the mortality of N. lugens were observed, with 100% of the insects fed on the SFI1/GNA fusion protein diet dead by day 7. The survival of the aphid M. persicae was also reduced when fed on the SFI1/GNA fusion protein. After 14 days, only 49% of the aphids that were fed on the fusion protein were still alive compared with approximately 90% of the aphids fed on the control diet or on diet containing GNA only. The SFI1/GNA fusion protein also slowed the development of M. persicae, and the reproductive capacity of the aphids fed on the SFI1/GNA fusion protein was severely reduced. The ability of GNA to act as a carrier protein, and deliver the SFI1 neurotoxin to the haemolymph of N. lugens, following oral ingestion, was investigated. The successful delivery of intact SFI1/GNA fusion protein to the haemolymph of these insects was shown by western blotting. Haemolymph taken from the insects that were fed on the fusion protein contained two GNA-immunoreactive proteins of molecular weights corresponding to GNA and to the SFI1/GNA fusion protein.

  15. Location of resistance factors in the leaves of potato and wild tuber-bearing Solanum species to aphyd Myzus persica

    NARCIS (Netherlands)

    Alvarez, A.E.; Tjallingii, W.F.; Garzo, E.; Vleeshouwers, V.; Dicke, M.; Vosman, B.

    2006-01-01

    Analysis of electrically recorded feeding behaviour of aphids was combined with colony-development tests to search for sources of resistance to Myzus persicae (Sulzer) (Homoptera: Aphididae) in tuber-bearing Solanum species (Solanaceae), aiming at a reduction of potato leaf roll virus (PLRV) transmi

  16. Insecticidal activity of three plants extracts against Myzus persicae (Sulzer, 1776 and their phytochemical screening

    Directory of Open Access Journals (Sweden)

    Billal NIA

    2015-11-01

    Full Text Available To reduce the use of synthetic pesticides and their negative effects on the environment, leaves extracts of Artemisia herba-alba Asso, Eucalyptus camaldulensis Dehnh and Rosmarinus officinalis L. were obtained with petroleum ether, ethanol and distilled water as solvents. These extracts were evaluated under laboratory conditions for their insecticidal effect against 3 to 4 days-old Myzus persicae individuals (Homoptera: Aphididae at 1, 2.5, 5, and 10 %. We made observations after 24 hours. Etheric extract of all plants was effective and caused mortalities (100 %, 53 % and 60 % respectively at the highest concentration. However, ethanolic and aqueous extracts did not show any significant insecticidal effect. The phytochemical screening showed the richness of etheric extract in terpenes. The results obtained suggest that we can make bioinsecticides based on leaves etheric extracts from these plants for use in integrated pest management.

  17. The 9-lipoxygenase Osr9-LOX1 interacts with the 13-lipoxygenase-mediated pathway to regulate resistance to chewing and piercing-sucking herbivores in rice.

    Science.gov (United States)

    Zhou, Guoxin; Ren, Nan; Qi, Jingfeng; Lu, Jing; Xiang, Caiyu; Ju, Hongping; Cheng, Jiaan; Lou, Yonggen

    2014-09-01

    Oxylipins produced by the 13-lipoxygenase (LOX) have been reported to play an important role in plant defense responses to herbivores. Yet, the role of oxylipins produced by the 9-LOX pathway in this process remains largely unknown. Here we cloned a gene encoding a chloroplast-localized 9-LOX, Osr9-LOX1, from rice. Transcriptional analysis revealed that herbivore infestation, mechanical wounding and jasmonic acid (JA) treatment either repressed or did not enhance the level of Osr9-LOX1 transcripts at early stages but did at later stages, whereas salicylic acid (SA) treatment quickly increased the transcript level of Osr9-LOX1. Antisense expression of Osr9-lox1 (as-r9lox1) decreased the amount of wound-induced (Z)-3-hexenal but increased levels of striped stem borer (SSB)-induced linolenic acid, JA, SA and trypsin protease inhibitors. These changes were associated with increased resistance in rice to the larvae of the SSB Chilo suppressalis. In contrast, although no significant differences were observed in the duration of the nymph stage or the number of eggs laid by female adults between the brown planthopper (BPH) Nilaparvata lugens that fed on as-r9lox1 lines and BPH that fed on wild-type (WT) rice plants, the survival rate of BPH nymphs that fed on as-r9lox1 lines was higher than that of nymphs that fed on WT plants, possibly because of a higher JA level. The results demonstrate that Osr9-LOX1 plays an important role in regulating an herbivore-induced JA burst and cross-talk between JA and SA, and in controlling resistance in rice to chewing and phloem-feeding herbivores.

  18. Insect abatement system

    Science.gov (United States)

    Spiro, Clifford Lawrence (Inventor); Burnell, Timothy Brydon (Inventor); Wengrovius, Jeffrey Hayward (Inventor)

    1997-01-01

    An insect abatement system prevents adhesion of insect debris to surfaces which must be kept substantially free of insect debris. An article is coated with an insect abatement coating comprising polyorganosiloxane with a Shore A hardness of less than 50 and a tensile strength of less than 4 MPa. A method for preventing the adhesion of insect debris to surfaces includes the step of applying an insect abatement coating to a surface which must be kept substantially free of insect debris.

  19. Insect Cell Culture

    NARCIS (Netherlands)

    Oers, van M.M.; Lynn, D.E.

    2010-01-01

    Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from lepidoptera

  20. Insect Cell Culture

    NARCIS (Netherlands)

    Oers, van M.M.; Lynn, D.E.

    2010-01-01

    Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from lepidoptera

  1. Allergies to Insect Venom

    Science.gov (United States)

    Allergies To Insect Venom Facts About Allergies The tendency to develop allergies may be inherited. If you have allergic tendencies and ... lives of those who are sensitive to it...insect venom! Although less common than pollen allergy, insect ...

  2. (E)-β-farnesene synthase genes affect aphid (Myzus persicae) infestation in tobacco (Nicotiana tabacum).

    Science.gov (United States)

    Yu, Xiudao; Jones, Huw D; Ma, Youzhi; Wang, Genping; Xu, Zhaoshi; Zhang, Baoming; Zhang, Yongjun; Ren, Guangwei; Pickett, John A; Xia, Lanqin

    2012-03-01

    Aphids are major agricultural pests which cause significant yield losses of the crop plants each year. (E)-β-farnesene (EβF) is the alarm pheromone involved in the chemical communication between aphids and particularly in the avoidance of predation. In the present study, two EβF synthase genes were isolated from sweet wormwood and designated as AaβFS1 and AaβFS2, respectively. Overexpression of AaβFS1 or AaβFS2 in tobacco plants resulted in the emission of EβF ranging from 1.55 to 4.65 ng/day/g fresh tissues. Tritrophic interactions involving the peach aphids (Myzus persicae), predatory lacewings (Chrysopa septempunctata) demonstrated that the transgenic tobacco expressing AaβFS1 and AaβFS2 could repel peach aphids, but not as strongly as expected. However, AaβFS1 and AaβFS2 lines exhibited strong and statistically significant attraction to lacewings. Further experiments combining aphids and lacewing larvae in an octagon arrangement showed transgenic tobacco plants could repel aphids and attract lacewing larvae, thus minimizing aphid infestation. Therefore, we demonstrated a potentially valuable strategy of using EβF synthase genes from sweet wormwood for aphid control in tobacco or other economic important crops in an environmentally benign way.

  3. Evidence for transmission of aphid-pathogenic fungi by migratory flight of Myzus persicae alates

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them for 7 d on detached cabbage leaves in Petri dishes. Among 760 alates trapped, 266 (35%) were found carrying various fungal pathogens, 87.3% of them died due to mycosis during the first 3-day period of rearing and the rest died in the following two days. Most of the deaths of the alates were attributed to entomophthoralean fungi, taking 94.4%, and the rest were the hyphomycetous fungus Beauveria bassiana. Among the Entomophthorales-killed alates, P. neoaphidis took a proportion of 66.1%, Z. anhuiensis 22.6%, E. planchoniana 9.7%, and N. fresenii 1.6%, respectively. Two alates were found suffering from cross infection of two fungal species, i.e. P. neoaphidis with Z. anhuiensis and N. fresenii, respectively. The results represent the first report on transmission of aphid-pathogenic fungi by M. persicae alates through migratory flight.

  4. Rapid method to screen resistance of potato plants against Myzus persicae (Homoptera: Aphididae) in the laboratory.

    Science.gov (United States)

    Le Roux, Vincent; Saguez, Julien; Vincent, Charles; Giordanengo, Philippe

    2004-12-01

    With the objective to develop a potato, Solanum tuberosum L., resistance program against aphids, we propose a rapid screening method with Myzus persicae (Sulzer) in the laboratory. We aimed to optimize the duration of the whole procedure and to decrease the frequency of measurements. In a first experiment, intrinsic rate of natural increase (r(m)) values were compared between adult aphids reared throughout their entire life and adults reared only during a period equivalent to their prereproductive period. No significant differences were observed. In a second experiment, four groups of aphids were distinguished according to the sampling frequency, i.e., those whose biological parameters were evaluated every single, second, third, and fourth day. Except for the fourth-day experiment, the r(m) values estimated on aphids reared on the three potato lines were not significantly different whatever sampling frequency of single, second, or third day used to check aphids. Thus, screening efforts in laboratory can be largely optimized by evaluating adult aphids only during a period equivalent to their prereproductive period and assessing M. persicae populations every third day. Our method is reliable and adapted to screen a large number of potato plants against M. persicae because it allows an average 70% reduction in the time required for the whole experimental process.

  5. Differential aphicidal effects of chitinase inhibitors on the polyphagous homopteran Myzus persicae (Sulzer).

    Science.gov (United States)

    Saguez, Julien; Dubois, Françoise; Vincent, Charles; Laberche, Jean-Claude; Sangwan-Norreel, Brigitte S; Giordanengo, Philippe

    2006-12-01

    Four chitinase inhibitors, cyclo-(Proline-Tyrosine), cyclo-(Histidine-Proline), allosamidin and psammaplin A, were selected for in vitro feeding experiments with the peach-potato aphid, Myzus persicae (Sulzer), under controlled photoperiod and temperature conditions. Artificial diets were used to provide chitinase inhibitors at 10, 50 and 100 microg mL(-1) to M. persicae. Except for cyclo-(Proline-Tyrosine), which did not modify aphid demographic parameters, chitinase inhibitors induced differential aphicidal effects on M. persicae. At all doses, cyclo-(Histidine-Proline) induced significant effects affecting daily fecundity, intrinsic rate of natural increase (r(m)) and doubling time of population. When compared with the control diet, allosamidin decreased nymph survival and daily fecundity, increasing the doubling time of population from 1 to 1.5 days. Psammaplin A was the most toxic inhibitor when delivered via artificial diet, as it induced the death of all aphids reared at 50 and 100 microg mL(-1). The results demonstrate the potential use of chitinase inhibitors as aphid management tools.

  6. Plant Essential Oils Synergize and Antagonize Toxicity of Different Conventional Insecticides against Myzus persicae (Hemiptera: Aphididae.

    Directory of Open Access Journals (Sweden)

    Nicoletta Faraone

    Full Text Available Plant-derived products can play an important role in pest management programs. Essential oils from Lavandula angustifolia (lavender and Thymus vulgaris (thyme and their main constituents, linalool and thymol, respectively, were evaluated for insecticidal activity and synergistic action in combination with insecticides against green peach aphid, Myzus persicae (Sulzer (Hemiptera: Aphididae. The essential oils and their main constituents exerted similar insecticidal activity when aphids were exposed by direct sprays, but were non-toxic by exposure to treated leaf discs. In synergism experiments, the toxicity of imidacloprid was synergized 16- to 20-fold by L. angustifolia and T. vulgaris essential oils, but far less synergism occurred with linalool and thymol, indicating that secondary constituents of the oils were probably responsible for the observed synergism. In contrast to results with imidacloprid, the insecticidal activity of spirotetramat was antagonized by L. angustifolia and T. vulgaris essential oils, and linalool and thymol. Our results demonstrate the potential of plant essential oils as synergists of insecticides, but show that antagonistic action against certain insecticides may occur.

  7. Plant Essential Oils Synergize and Antagonize Toxicity of Different Conventional Insecticides against Myzus persicae (Hemiptera: Aphididae).

    Science.gov (United States)

    Faraone, Nicoletta; Hillier, N Kirk; Cutler, G Christopher

    2015-01-01

    Plant-derived products can play an important role in pest management programs. Essential oils from Lavandula angustifolia (lavender) and Thymus vulgaris (thyme) and their main constituents, linalool and thymol, respectively, were evaluated for insecticidal activity and synergistic action in combination with insecticides against green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae). The essential oils and their main constituents exerted similar insecticidal activity when aphids were exposed by direct sprays, but were non-toxic by exposure to treated leaf discs. In synergism experiments, the toxicity of imidacloprid was synergized 16- to 20-fold by L. angustifolia and T. vulgaris essential oils, but far less synergism occurred with linalool and thymol, indicating that secondary constituents of the oils were probably responsible for the observed synergism. In contrast to results with imidacloprid, the insecticidal activity of spirotetramat was antagonized by L. angustifolia and T. vulgaris essential oils, and linalool and thymol. Our results demonstrate the potential of plant essential oils as synergists of insecticides, but show that antagonistic action against certain insecticides may occur.

  8. Concentration-mortality responses of Myzus persicae and natural enemies to selected insecticides.

    Science.gov (United States)

    Bacci, Leandro; Rosado, Jander F; Picanço, Marcelo C; Pereira, Eliseu J G; Silva, Gerson A; Martins, Júlio C

    2012-01-01

    The toxicity of six insecticides was determined for the peach-potato aphid, Myzus persicae (Hemiptera: Aphididae), and some of its natural enemies - the predatory beetles Cycloneda sanguinea (Coccinellidae) and Acanthinus sp. (Anthicidae), and the wasp parasitoid Diaeretiella rapae (Aphidiidae). Natural enemies from these groups are important natural biological control agents in a number of agroecosystems, and insecticides potentially safe to these non-target organisms should be identified using standardized tests. Thus, concentration-mortality bioassays were carried out with both the aphid and its natural enemies to assess the toxicity and selectivity of acephate, deltamethrin, dimethoate, methamidophos, methyl parathion, and pirimicarb. The latter insecticide was highly selective to all natural enemies tested, and its LC(90) for M. persicae was 14-fold lower than the field rate recommended for control of the aphid in brassica crops. Methyl parathion also showed selectivity to C. sanguinea and Acanthinus sp., but not to D. rapae. Acephate was the least potent insecticide against M. persicae and was equally or more toxic to the natural enemies relative to the aphid. Pirimicarb and methyl parathion were efficient against M. persicae and selective in favor of two of the natural enemies tested. Acanthinus sp. and C. sanguinea were more tolerant to the insecticides than was the parasitoid D. rapae. This study shows that there are selective insecticides that may be compatible with conservation of natural enemies in brassica crops, which is important practical information to improve integrated pest management systems in these crops.

  9. Preference of the green peach aphid, Myzus persicae, for plants grown in sewage sludges

    Energy Technology Data Exchange (ETDEWEB)

    Culliney, T.W.; Pimentel, D.

    1987-08-01

    Since passage of the Clean Water Act in the 1970s, disposal of the millions of tonnes of sewage sludge generated annually has become a major concern of municipalities throughout the United States. With the range of other disposal options having narrowed in recent years, application of sludge to land is increasingly viewed as a practical and economical means to recycle this waste material. However, sludges from large cities with industries may be contaminated with various toxic chemicals, including polychlorinated biphenyls (PCBs), other organic chemicals, such as pesticides, and heavy metals. Sludge application to land thus has the potential adversely to affect biota and the functioning of terrestrial ecosystems. The authors previously demonstrated marked reductions in fecundity and survival of green peach aphids, Myzus persicae, on collard plants, Brassica oleracea var. sabellica, growing in soil treated with chemically contaminated sludge as compared to aphids on plants growing either in soil treated with uncontaminated sludge of soil conventionally fertilized. Reduced plant growth and increased restlessness in aphids in the contaminated sludge treatment were also observed. The purpose of the present study was to examine more closely the influence of sludge contaminants on aphid settling behavior as indicated by differential preference of M. persicae for leaves of its collard host grown under different soil conditions.

  10. Abscisic acid deficiency increases defence responses against Myzus persicae in Arabidopsis.

    Science.gov (United States)

    Hillwig, Melissa S; Chiozza, Mariana; Casteel, Clare L; Lau, Siau Ting; Hohenstein, Jessica; Hernández, Enrique; Jander, Georg; MacIntosh, Gustavo C

    2016-02-01

    Comparison of Arabidopsis thaliana (Arabidopsis) gene expression induced by Myzus persicae (green peach aphid) feeding, aphid saliva infiltration and abscisic acid (ABA) treatment showed a significant positive correlation. In particular, ABA-regulated genes are over-represented among genes that are induced by M. persicae saliva infiltration into Arabidopsis leaves. This suggests that the induction of ABA-related gene expression could be an important component of the Arabidopsis-aphid interaction. Consistent with this hypothesis, M. persicae populations induced ABA production in wild-type plants. Furthermore, aphid populations were smaller on Arabidopsis aba1-1 mutants, which cannot synthesize ABA, and showed a significant preference for wild-type plants compared with the mutant. Total free amino acids, which play an important role in aphid nutrition, were not altered in the aba1-1 mutant line, but the levels of isoleucine (Ile) and tryptophan (Trp) were differentially affected by aphids in wild-type and mutant plants. Recently, indole glucosinolates have been shown to promote aphid resistance in Arabidopsis. In this study, 4-methoxyindol-3-ylmethylglucosinolate was more abundant in the aba1-1 mutant than in wild-type Arabidopsis, suggesting that the induction of ABA signals that decrease the accumulation of defence compounds may be beneficial for aphids. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  11. Uso de cuatro extractos organicos para el control del pulgon verde (Myzus persicae Sulz (ING

    Directory of Open Access Journals (Sweden)

    Hernán Rodríguez Navas

    2016-03-01

    Full Text Available Extracts of leaves and stems of Neurolaena lobata; leaves, stems and fruits of Momordica charantia, wood of Quassia amara and seeds of Annona muricata, were tested regarding their effectiveness for control of green peach aphid (Myzus persicae. In a first stage, groups of 10 individuals of M. persicae were placed inside petri dishes together with a small and slight piece of synthetic cloth soaked with either substance extracted. Several concentrations were used. After two hours; more than 50% of the individuals had been killed in every petri dish, which allowed all extracts to pass on to the second stage. The second stage consisted of two experiments. The first one was done in spring at a greenhouse day temperature of 10°C,  using only the first three substances, each of them diluted 1:100. The second one was conducted in Summer at about 25°C with the four substances. Distilled water acted as a control in both experiments. Tobacco plants (Nicotiana tabacum infested with M. persicae were sprayed with the solutions and survivors counted 24 and 72 hours later. In the first experiment Q amara  and M. charantia had 78% and 77% effectiveness respectively, which were statiscally (P< 0.05 higher than that of N. lobata  (63%. In the second experiment, because of the warmer weather, they improved their performance, specially N. lobata (98%. This and A. muricata were found statistically (P< 0.05 higher than the others.

  12. Bioactivity of aqueous extracts of Clibadium sylvestre (Aubl. Baill. and Derris amazonica Killip on the aphid Myzus persicae (Sulzer, 1776 (Hemiptera: Aphididae Bioatividade de extratos aquosos de Clibadium sylvestre (Aubl. Baill. e Derris amazonica Killip no controle do pulgão Myzus persicae (Sulzer (Hemiptera: Aphididae

    Directory of Open Access Journals (Sweden)

    Camila Cramer Filgueiras

    2011-12-01

    Full Text Available Studies with botanical insecticides have become more popular as an alternative to Integrated Pest Management. The purpose of this study was to evaluate the effect of leaf and fruit aqueous extracts, from the species Clibadium sylvestre, and leaves and root of Derris amazonica species at concentrations of 0, 1, 2, 4 and 8%, in the control of the aphid Myzus persicae (Hemiptera: Aphididae. Four experiments were conducted; two tests with choice preference and two tests with no choice preference, giving nine treatments and five repetitions. Phytochemical screening was carried out from the leaves and fruit of the species C. sylvestre and leaves and root of D. amazonica. Evaluations of mortality, number of nymphs, and deterrence index of the insects were conducted 24, 48 and 72 h after the application of the extracts. The aqueous extracts tested from C. sylvestre fruit concentrations had the highest mortality compared to the control; in the analysis of the number of the nymphs, the aqueous extract from fruit at 8% concentration had a higher efficiency than the other treatments. The D. amazonica leaves extract at 1% concentration showed the highest mortality and the lowest number of nymphs. The D. amazonica root extracts increased mortality at all concentrations tested, and the 8% concentration had the fewest nymphs. All treatments showed a deterrent effect. The 72 h period showed the greatest effect of the extracts, on two species of insects.Estudos com inseticidas botânicos vêm ganhando espaço como alternativa no Manejo Integrado de Pragas. Conduziu-se este trabalho com o objetivo de avaliar o efeito de extratos aquosos de folhas e frutos da espécie Clibadium sylvestre, e folhas e raízes da espécie Derris amazonica nas concentrações 0, 1, 2, 4 e 8%, no controle do pulgão Myzus persicae (Hemiptera: Aphididae. Foram conduzidos quatro ensaios, dois testes de preferência sem chance de escolha e dois testes de preferência com chance de escolha

  13. RNA interference against gut osmoregulatory genes in phloem-feeding insects.

    Science.gov (United States)

    Tzin, Vered; Yang, Xiaowei; Jing, Xiangfeng; Zhang, Kai; Jander, Georg; Douglas, Angela E

    2015-08-01

    In planta RNAi (i.e. plants engineered to synthesize active RNAi molecules) has great potential as a strategy to control insect crop pests. This study investigated the impact of RNAi against osmoregulatory genes expressed in the gut of two phloem-feeding species, the green peach aphid Myzus persicae and the potato/tomato psyllid Bactericera cockerelli. The target genes comprising candidate gut sucrase, aquaporin and sugar transporter genes were identified by mining insect genomic and transcriptomic datasets for genes orthologous to empirically-tested osmoregulatory genes of the pea aphid Acyrthosiphon pisum. Insects feeding on plants with RNAi against the target genes exhibited elevated hemolymph osmotic pressure (a predicted effect of perturbed osmotic function) and some reduction in performance, especially offspring production in M. persicae and mortality in B. cockerelli, associated with up to 50% reduction in mean expression of the target genes. The effects were particularly pronounced for insects treated with RNAi against multiple osmoregulatory genes, i.e. combinatorial RNAi, suggesting that the partial silencing of multiple genes with related roles can yield greater functional impairment than RNAi against a single gene. These results demonstrate the potential of RNAi against osmoregulatory genes, but further advances to improve the efficacy of RNAi in phloem-feeding insects are required to achieve effective pest control.

  14. The Control Efficiency of Plant Alcohol Extracts on the Laboratory Populations of Myzus persicae (Sulzer)and Lipaphis erysimi (Kaltenbach)

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qiong; LIANG Guang-wen; ZENG Ling; SHEN Shu-ping

    2002-01-01

    The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus persicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (ⅡPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr.Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant protectant to protect crops.

  15. Book Review: Insect Virology

    Science.gov (United States)

    Viruses that infect insects have long been of interest both as a means for controlling insect pest populations in an environmentally safe manner, and also as significant threats to beneficial insects of great value, such as honey bees and silkworms. Insect viruses also have been of intrinsic intere...

  16. [Effects of Beauveria bassiana on Myzus persicae and its two predaceous natural enemies].

    Science.gov (United States)

    Zhu, Hong; Luo, Xu-mei; Song, Jin-xin; Fan, Mei-zhen; Li, Zeng-zhi

    2011-09-01

    A Beauveria bassiana strain Bb21 was isolated from naturally infected green peach aphid Myzus persicae (Hemiptera: Aphididae). The effects of the strain on M. persicae and its two predaceous natural enemies Chrysoperla carnea (Neuroptera: Chrysopidae) and Harmonia axyridis (Coleoptera: Coccinellidae) were investigated under laboratory conditions. Bb21 had strong pathogenicity to M. persicae, with the LD50 of 97 conidia x mm(-2) (45-191, 95% confidence interval), but was less pathogenic to the second instar nymph of C. carnea, with the LD50 of 1089 conidia x mm(-2). The LD50 for C. carnea was 10.2 times higher than that for M. persicae. The pathogenicity of Bb21 to H. axyridis was very weak, with a low infection rate of 13% even at a high concentration 5 x 10(8) conidia x mL(-1). The Bb21 at low conidia concentration had less effect on the developmental period and fecundity of the two predaceous natural enemies. However, when applied at the high concentration 5 x 10(8) spores x mL(-1), Bb21 shortened the larval stage of H. axyridis averagely by 1.4 d and decreased the adult emergence rate and fecundity by 33% and 14%, respectively, and shortened the larval stage of C. carnea averagely by 0.7 d and decreased the adult emergence rate and fecundity by 24% and 11%, respectively. Since the LD50 for green peach aphid was much lower than that for the two predaceous natural enemies, and had very low effect on the adult emergence rate and fecundity of the two predators at the concentration recommended for field spray, Bb21 could be applied as a biocontrol agent of M. persicae in the integrated management of pernicious organisms.

  17. Host-correlated morphological variation of Myzus persicae (Hemiptera: Aphididae) populations in Greece.

    Science.gov (United States)

    Margaritopoulos, J T; Tsitsipis, J A; Zintzaras, E; Blackman, R L

    2000-06-01

    Morphological variation in nine characters of 157 clones of Myzus persicae (Sulzer) was examined by multivariate analysis. The clones were collected from peach, Prunus persica, the primary host and the secondary hosts tobacco, Nicotiana tabacum, cabbage, Brassica oleracea, sugarbeet, Beta vulgaris and pepper Capsicum annuum. The 156 clones originated from various regions of Greece, both in the north, where a large part of the population has an annual bisexual generation on peach, and in more southerly regions, where populations are predominantly unisexual. One clone was collected from tobacco in Caserta, Italy. All clones were laboratory-reared on potato. Canonical variate analysis, hierarchical cluster analysis and a non-parametric classification tree method both revealed morphological differences associated with the host-plant on which they were collected. The scores of the first two canonical variates separated the tobacco-feeding clones from those originating from other secondary host-plants. However, in tobacco-growing areas the tobacco-feeding form predominated in spring populations on peach, and was sometimes found on other secondary hosts. In addition, using cluster analysis, the clones from tobacco which were sampled in the most southeasterly region showed a relatively large phenotypic distance from those collected further north and west. Moreover, clonal phenotypes were affected both by host plant and by long-term parthenogenetic rearing. However, in spite of these effects, the tobacco form was generally distinguishable from aphids originating from other hosts, indicating that the difference must have a genetic basis. In separate analyses of the clones originating from secondary hosts no association was found between morphology and either life cycle category or colour. Discriminant analysis showed that 89% of 1723 specimens could be correctly classified into the two groups.

  18. Screening of Uruguayan plants for deterrent activity against insects.

    Science.gov (United States)

    Castillo, Lucía; González-Coloma, Azucena; González, Andrés; Díaz, Martina; Santos, Estela; Alonso-Paz, Eduardo; Bassagoda, María Julia; Rossini, Carmen

    2009-01-01

    We evaluated the anti-insectan activity of extracts from different vegetative parts of ten plant species native to Uruguay. The selected plants belong to five families: Bignoniaceae: Clytostoma callistegioides, Dolichandra cynanchoides, Macfadyena unguis-cati; Sapindaceae: Dodonaea viscosa, Allophylus edulis, Serjania meridionalis; Lamiaceae: Salvia procurrens, Salvia guaranitica; Solanaceae: Lycium cestroides; and Phytolaccaceae: Phytolacca dioica. The extracts were evaluated in independent bioassays against four insect pests and one beneficial insect. Aphid settling inhibition was evaluated with a grass specialist, Rhopalosiphum padi, and a feeding generalist, Myzus persicae (both Hemiptera: Aphididae). Antifeedant activity was tested with adults of the specialist Epilachna paenulata (Coleoptera: Coccinellidae) and larvae of the generalist Spodoptera littoralis (Lepidoptera: Noctuidae). Finally, contact toxicity was assessed with honey bees, Apis mellifera (Hymenoptera: Apidae). Strong settling inhibition (SI) activity (expressed as %SI, where 100% means complete inhibition by the extract) was found only for the twig extracts of A. edulis (Sapindaceae) against M. persicae (% SI = 77 +/- 4). Antifeedant activity (expressed as % of feeding reduction (FR), where 100% means no consumption on extract-treated diet) against E. paenulata was significant for the leaf extracts of L. cestroides (Solanaceae) (% FR = 100 +/- 0) as well as of all Bignoniaceae and Sapindaceae species. No extracts were active against S. littoralis larvae, and most of them were innocuous to honey bees, with the exception of L. cestroides and S. meridionalis leaf extracts.

  19. Evolutionary conservation of candidate osmoregulation genes in plant phloem sap-feeding insects.

    Science.gov (United States)

    Jing, X; White, T A; Luan, J; Jiao, C; Fei, Z; Douglas, A E

    2016-06-01

    The high osmotic pressure generated by sugars in plant phloem sap is reduced in phloem-feeding aphids by sugar transformations and facilitated water flux in the gut. The genes mediating these osmoregulatory functions have been identified and validated empirically in the pea aphid Acyrthosiphon pisum: sucrase 1 (SUC1), a sucrase in glycoside hydrolase family 13 (GH13), and aquaporin 1 (AQP1), a member of the Drosophila integral protein (DRIP) family of aquaporins. Here, we describe molecular analysis of GH13 and AQP genes in phloem-feeding representatives of the four phloem-feeding groups: aphids (Myzus persicae), coccids (Planococcus citri), psyllids (Diaphorina citri, Bactericera cockerelli) and whiteflies (Bemisia tabaci MEAM1 and MED). A single candidate GH13-SUC gene and DRIP-AQP gene were identified in the genome/transcriptome of most insects tested by the criteria of sequence motif and gene expression in the gut. Exceptionally, the psyllid Ba. cockerelli transcriptome included a gut-expressed Pyrocoelia rufa integral protein (PRIP)-AQP, but has no DRIP-AQP transcripts, suggesting that PRIP-AQP is recruited for osmoregulatory function in this insect. This study indicates that phylogenetically related SUC and AQP genes may generally mediate osmoregulatory functions in these diverse phloem-feeding insects, and provides candidate genes for empirical validation and development as targets for osmotic disruption of pest species. © 2016 The Authors. Insect Molecular Biology published by John Wiley & Sons Ltd on behalf of The Royal Entomological Society.

  20. Insect Bites and Stings

    Science.gov (United States)

    Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, ...

  1. Insects: An Interdisciplinary Unit

    Science.gov (United States)

    Leger, Heather

    2007-01-01

    The author talks about an interdisciplinary unit on insects, and presents activities that can help students practice communication skills (interpersonal, interpretive, and presentational) and learn about insects with hands-on activities.

  2. Insects and Scorpions

    Science.gov (United States)

    ... and Products Programs Contact NIOSH NIOSH INSECTS AND SCORPIONS Recommend on Facebook Tweet Share Compartir Stinging or biting insects or scorpions can be hazardous to outdoor workers. Stinging or ...

  3. Respiration in Aquatic Insects.

    Science.gov (United States)

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  4. Insect glutathione transferases.

    Science.gov (United States)

    Ketterman, Albert J; Saisawang, Chonticha; Wongsantichon, Jantana

    2011-05-01

    This article is an overview of the current knowledge of insect glutathione transferases. Three major topics are discussed: the glutathione transferase contributions to insecticide resistance, the polymorphic nature of the insect glutathione transferase superfamily, and a summary of the current structure-function studies on insect glutathione transferases.

  5. Exploring Sound with Insects

    Science.gov (United States)

    Robertson, Laura; Meyer, John R.

    2010-01-01

    Differences in insect morphology and movement during singing provide a fascinating opportunity for students to investigate insects while learning about the characteristics of sound. In the activities described here, students use a free online computer software program to explore the songs of the major singing insects and experiment with making…

  6. The Occurrence of Two Species of Entomophthorales (Entomophthoromycota, Pathogens of Sitobion avenae and Myzus persicae (Hemiptera: Aphididae, in Tunisia

    Directory of Open Access Journals (Sweden)

    Ibtissem Ben Fekih

    2013-01-01

    Full Text Available The natural occurrence of entomophthoralean fungi pathogenic towards aphids on cereal and potato crops was investigated in the years 2009, 2010, and 2011. Infected aphids were sampled in three bioclimatic zones in Tunisia (Beja, Cap bon, and Kairouan and fungal species were determined based on morphological characters such as shape, size, and number of nuclei in the primary conidia. Polymerase Chain Reaction (PCR on the internal transcribed spacer 1 region (ITS1 was used to verify morphological determination. Both methods gave consistent results and we documented for the first time the natural occurrence of two fungal species from the order Entomophthorales (phylum Entomophthoromycota, Pandora neoaphidis and Entomophthora planchoniana. Both fungi were recorded on the aphid species Sitobion avenae and Myzus persicae on barley ears and potato leaves, respectively. Moreover, natural mixed infections by both species (P. neoaphidis and E. planchoniana were documented on the target aphids. This investigation provides basic information of entomopathogenic fungi infecting economically important aphids in Tunisia.

  7. Probiotic effects of beta-glucuronidase on the peach-potato aphid Myzus persicae (Aphididae).

    Science.gov (United States)

    Cherqui, A; Alla, S; Saguez, J; Doury, G; Sangwan-Norreel, B S; Giordanengo, P

    2003-12-01

    beta-glucuronidase (GUS) is a reporter protein commonly expressed in transgenic plants allowing the visualization of the transformed individuals. In our recent work, we showed that consumption of transformed potato plants expressing this GUS enzyme improves performance of the phloem feeding aphid Myzus persicae. Those results led us to the conclusion that the expression of GUS in potato plants might be responsible for the probiotic effect measured in feeding aphids. In the present paper, artificial diets were used to provide active GUS (10 and 500 microg ml(-1)), inactivated heated GUS (500 microg ml(-1)), glucuronic acid (10, 100 and 500 microg ml(-1)), and bovine serum albumin (500 microg ml(-1)) to M. persicae. Our results reveal that these chemicals provided as food intake might influence the biological parameters of this aphid. Experiments showed a probiotic effect of 500 microg ml(-1) GUS diet, resulting in reduced larval mortality, and increased adult reproduction period and fecundity, which led to an increased population growth potential (r(m)=0.17+/-0.01 versus r(m)=0.12+/-0.03 for aphids fed on control diet). A lower amount of added GUS led to fewer variations, biological parameters being only slightly altered (r(m)=0.14+/-0.03). Statistically similar alterations of the biological parameters were obtained when comparing aphids fed on the diet added with inactivated GUS or the non-structural bovine serum albumin protein (r(m)=0.15+/-0.02 and 0.14+/-0.03, respectively). Feeding assays conducted with glucuronic acid supplemented diets enhanced longevity and nymph production of the adult aphids and reduced larval mortality, resulting in r(m)=0.15+/-0.02 for the highest dose (500 microg ml(-1)). Although 100 microg ml(-1) glucuronate diet did not induce any effect on M. persicae (r(m)=0.12+/-0.03), aphids fed on 10 microg ml(-1) glucuronate diet exhibited unexpected reduced demographic parameters (r(m)=0.10+/-0.03). Immuno-histological analysis showed GUS

  8. Broadening insect gastronomy

    DEFF Research Database (Denmark)

    Halloran, Afton Marina Szasz; Münke, Christopher; Vantomme, Paul

    2015-01-01

    and visual characteristics, is an example of an area of nature that requires further gastronomic exploration. Many parts of the world consume insects, neither as a novelty nor as a fall-­back famine food (FAO, 2013). Insect-­consuming populations often eat them as a delicacy, seeing each insect......In recent years there has been a trend among chefs to diversify their ingredients and techniques, drawing inspiration from other cultures and creating new foods by blending this knowledge with the flavours of their local region. Edible insects, with their plethora of taste, aromatic, textural...... as an ingredient in its own right – not collectively as ‘insects’, as it is easy for many uninitiated to do. Many of these insects frequently fetch higher prices than other meat sources in the market, and it is this approach of investigating insects as a delicious gastronomic product that interests us. Indeed...

  9. Proteomics and insect immunity

    Directory of Open Access Journals (Sweden)

    L Shi

    2006-01-01

    Full Text Available Insect innate immunity is both a model for vertebrate immunity as well as a key system that impactsmedically important pathogens that are transmitted by insects. Recent developments in proteomics andprotein identification techniques combined with the completion of genome sequences for Anophelesgambiae and Drosophila melanogaster provided the tools for examining insect immunity at a new level ofmolecular detail. Application of proteomics to insect immunity resulted in predictions of new roles inimmunity for proteins already known in other contexts (e.g. ferritin, transferrin, Chi-lectins and helped totarget specific members of multi-gene families that respond to different pathogens (e.g. serine proteases,thioester proteins. In addition, proteomics studies verify that post-translational modifications play a keyrole in insect immunity since many of the identified proteins are modified in some way. These studiescomplement recent work on insect transcriptomes and provide new directions for further investigation ofinnate immunity.

  10. Insects and sex

    OpenAIRE

    Beukeboom, Leo

    2005-01-01

    Most organisms reproduce sexually, but the evolution of sexual reproduction is not yet well understood. Sexual reproduction leads to new variation and adaptations to the environment, but sex is also costly. Some insects reproduce without sex through parthenogenesis or paedogenesis. Almost all sexual insects have two separate sexes, male and female. There are many mechanisms of sex determination. Most insects have male heterogamety (males XY, females XX). Female heterogamety and haplodiploidy ...

  11. Ability of Aphis gossypii and Myzus persicae to Transmit Cucumber mosaic virus in Single and Mixed Infection with Two Potyviruses to Zucchini Squash

    OpenAIRE

    Pinto, Zayame Vegette [UNESP; Rezende,Jorge Alberto Marques; Yuki, Valdir Atsushi; Piedade,Sônia Maria de Stefano

    2008-01-01

    The main objective of this work was to investigate the ability of Aphis gossypii and Myzus persicae to transmit Cucumber mosaic virus (CMV) singly and mixed with two potyviruses (Papaya ringspot virus - type W, PRSV-W and Zucchini yellow mosaic virus, ZYMV), to zucchini squash plants (Cucurbita pepo). The results showed that the potyviruses in general were more efficiently transmitted by both species of aphids as compared to CMV. The transmission of PRSV-W, ZYMV and CMV separately was more ef...

  12. Avaliação de inseticidas no controle de Myzus persicae (sulz. (homoptera: aphididae na cultura da alface Evaluation of insecticides to control Myzus persicae (Sulz (Homoptera: Aphididae on lettuce crop

    Directory of Open Access Journals (Sweden)

    Jeferson Zagonel

    2002-09-01

    Full Text Available Foi avaliada a eficiência de inseticidas no controle de Myzus persicae (Sulz. na cultura da alface, cv. Verônica, em experimento conduzido na UEPG, em 1999. Usou-se delineamento experimental de blocos ao acaso com seis tratamentos e quatro repetições. Os tratamentos constaram de thiamethoxam nas doses de 50; 75 e 100 g i.a./ha; imidacloprid na dose de 140 g i.a./ha; pymetrozine na dose de 150 g i.a./ha e testemunha sem pulverização. Os tratamentos foram aplicados nas mudas em bandejas, um dia antes do transplantio. Avaliou-se a fitotoxicidade, o número de pulgões por planta, a porcentagem de plantas com pulgões e a eficiência dos inseticidas. O thiamethoxam nas doses de 50; 75 e 100 g i.a./ha foi eficiente no controle de M. persicae durante todo o ciclo, mostrando eficiência igual ou superior a 98,6%, similar ao imidacloprid. O pymetrozine apresentou eficiência no controle de M. persicae até 21 dias após o transplante das mudas. Os inseticidas não causaram efeitos fitotóxicos nas plantas de alface; além disso, houve produção de plantas com maior massa fresca em relação à testemunha.A field trial was carried out at Universidade Estadual de Ponta Grossa, State of Paraná, Brazil, in 1999, to evaluate the efficiency of insecticides in controlling Myzus persicae (Sulz on lettuce cv. Veronica. The experimental design was of completely randomized blocks with six treatments and four replications. The treatments consisted of thiamethoxam (50; 75 and 100 g i.a/ha imidacloprid (140 g i.a/ha; pymetrozine (150 g i.a/ha and control. The treatments were applied to seedlings grown in polyestyrene trays one day before the transplanting. The fitotoxicity, the number of aphids/plant, the percentage of plants with aphids and the efficiency of the insecticides were evaluated. Thiamethoxan at doses of 50; 75 and 100 g i.a/ha was efficient to control M. persicae from transplanting till 43 days after showing equal or higher efficiency than 98

  13. Insects and Bugs

    Science.gov (United States)

    Sutherland, Karen

    2009-01-01

    They have been around for centuries. They sting, they bite. They cause intense itching or painful sores. They even cause allergic reactions and sometimes death. There are two types of insects that are pests to humans--those that sting and those that bite. The insects that bite do so with their mouths and include mosquitoes, chiggers, and ticks.…

  14. Insects: Bugged Out!

    Science.gov (United States)

    Piehl, Kathy

    2011-01-01

    Insects really need no introduction. They have lived on earth much longer than humans and vastly outnumber people and all other animal species combined. People encounter them daily in their houses and yards. Yet, when children want to investigate insects, books can help them start their explorations. "Paleo Bugs" carries readers back to the time…

  15. Stinging Insect Allergy

    Science.gov (United States)

    ... and perfume when outdoors. Because the smell of food attracts insects, be careful outdoors when cooking, eating or drinking sweet drinks like soda or juice. Beware of insects inside straws or canned drinks. Keep food covered until eaten. Wear closed-toe shoes outdoors ...

  16. Insect bites and stings

    Science.gov (United States)

    ... likely to cause itching than pain. Insect and spider bites cause more deaths from venom reactions than bites from snakes. ... are harmless. If possible, bring the insect or spider that bit you with you when you go for medical treatment so it can be identified.

  17. Potencial de manejo de Myzus persicae com óleo de pinhão manso armazenado em diferentes embalagens

    Directory of Open Access Journals (Sweden)

    Anderson Mathias Holtz

    2015-12-01

    Full Text Available Myzus persicae vem provocando prejuízos em diversas hortícolas. A utilização de inseticidas químicos vem proporcionando graves problemas na agricultura e meio ambiente. Métodos alternativos de controle têm-se tornado uma ferramenta eficaz no manejo de pragas, como a utilização de plantas inseticidas. Com o objetivo de reduzir e/ou substituir os agrotóxicos sintéticos por produtos ecologicamente corretos, este trabalho visou estudar a potencialidade inseticida do óleo de Jatropha curcas sobre o pulgão verde da couve, armazenado por 180 dias, em diferentes embalagens. Foram utilizados discos de folhas de couve contendo 10 pulgões, os quais foram imersos em solução de óleo de pinhão manso nas concentrações 0,0; 0,5; 1,0; 2,0 %. A mortalidade variou em função do tempo de armazenamento, concentração e do uso de diferentes tipos de recipientes, ocorrendo interação significativa entre esses fatores. Os polietilenos “pet branco”, “iogurte” e vidro de cor âmbar apresentaram maior mortalidade na concentração de 2 % ao longo do tempo, sendo que a maior mortalidade (99, 100 e 98 % foi obtida no período de 120, 150 e 60 dias de armazenamento, respectivamente. O polietileno “pet verde” também apresentou maior mortalidade na concentração de 2 % até os 150 dias. Essa foi de 100 % no tempo de armazenamento zero e de 14,6 % no tempo de 180 dias, demonstrando, nesse caso, que o tempo de armazenamento em garrafa “pet verde” interfere na ação do óleo sobre M. persicae. Conclui-se que óleo de pinhão manso, mesmo armazenado em diferentes recipientes ao longo do tempo, demonstra potencial no manejo de M. persicae. Palavras-chave: Myzus persicae. Jatropha curcas. Manejo alternativo.

  18. HrpNEa -induced deterrent effect on phloem feeding of the green peach aphid Myzus persicae requires AtGSL5 and AtMYB44 genes in Arabidopsis thaliana

    Indian Academy of Sciences (India)

    Beibei Lü; Weiwei Sun; Shuping Zhang; Chunling Zhang; Jun Qian; Xiaomeng Wang; Rong Gao; Hansong Dong

    2011-03-01

    In Arabidopsis thaliana (Arabidopsis) treated with the harpin protein HrpNEa, resistance to the green peach aphid Myzus persicae, a generalist phloem-feeding insect, develops with induced expression of the AtMYB44 gene. Special GLUCAN SYNTHESIS-LIKE (GSL) genes and -1,3-glucan callose play an important role in plant defence responses to attacks by phloem-feeding insects. Here we report that AtGLS5 and AtMYB44 are both required for HrpNEa-induced repression of M. persicae feeding from the phloem of Arabidopsis leaves. In 24 h successive surveys on large-scale aphid populations, the proportion of feeding aphids was much smaller in HrpNEa-treated plants than in control plants, and aphids preferred to feed from the 37 tested atgsl mutants rather than the wild-type plant. The atgsl mutants were generated previously by mutagenesis in 12 identified AtGSL genes (AtGSL1 through AtGSL12); in the 24 h survey, both atgsl5 and atgsl6 tolerated aphid feeding, and atgsl5 was the most tolerant. Consistently, atgsl5 was also most inhibitive to the deterrent effect of HrpNEa on the phloem-feeding activity of aphids as monitored by the electrical penetration graph technique. These results suggested an important role of the AtGSL5 gene in the effect of HrpNEa. In response to HrpNEa, AtGSL5 expression and callose deposition were induced in the wild-type plant but not in atgsl5. In response to HrpNEa, moreover, the AtMYB44 gene known to be required for repression of aphid reproduction on the plant was also required for repression of the phloem-feeding activity. Small amounts of the AtGSL5 transcript and callose deposition were detected in the atmyb44 mutant, as in atgsl5. Both mutants performed similarly in tolerating the phloem-feeding activity and impairing the deterrent effect of HrpNEa, suggesting that AtGSL5 and AtMYB44 both contributed to the effect.

  19. Sublethal Effects of Cyantraniliprole and Imidacloprid on Feeding Behavior and Life Table Parameters of Myzus persicae (Hemiptera: Aphididae).

    Science.gov (United States)

    Zeng, Xianyi; He, Yingqin; Wu, Jiaxing; Tang, Yuanman; Gu, Jitao; Ding, Wei; Zhang, Yongqiang

    2016-08-01

    The green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), is an agricultural pest that seriously infests many crops worldwide. This study used electrical penetration graphs (EPGs) and life table parameters to estimate the sublethal effects of cyantraniliprole and imidacloprid on the feeding behavior and hormesis of M. persicae The sublethal concentrations (LC30) of cyantraniliprole and imidacloprid against adult M. persicae were 4.933 and 0.541 mg L(-1), respectively. The feeding data obtained from EPG analysis indicated that the count probes and number of short probes (imidacloprid-treated plants. In addition, the phloem-feeding behavior of M persicae was significantly impaired on fed tobacco plants treated with cyantraniliprole and imidacloprid at LC30 Analysis of life table parameters indicated that the growth and reproduction of F1 generation aphids were significantly affected when initial adults were exposed to LC30 of cyantraniliprole and imidacloprid. The nymphal period, female longevity, total preoviposition period, and mean generation time were significantly prolonged when initial adults were exposed to LC30 of imidacloprid. By comparison, these parameters were prolonged but not significantly in the cyantraniliprole treatment. The fecundity and gross reproductive rate were significantly increased in the treated groups. Similarly, the net reproductive rate was greater in the treated group than the control group. Our results indicate that treatment with LC30 of imidacloprid and cyantraniliprole would lead to a hormetic response of M. persicae, with higher likelihood of occurrence when initial adults were exposed to LC30 of cyantraniliprole.

  20. Colonization of the biomass energy crop miscanthus by the three aphid species, Aphis fabae, Myzus persicae, and Rhopalosiphum padi.

    Science.gov (United States)

    Coulette, Q; Couty, A; Lasue, P; Rambaud, Z C; Ameline, A

    2013-04-01

    Miscanthus is a perennial C4-grass that has received much interest as a potential of impact on the local agroecosytem. In this context, laboratory experiments were conducted to investigate the potential colonization of this new exotic plant species by three of the main aphid pest species of common crops in Picardie, northern France. In host preference experiments, the two polyphagous aphid species studied, Aphis fabae (Scop) and Myzus persicae (Sulzer), exhibited an xclusive preference for their host plant, whereas the cereal specialist Rhopalosiphum padi (L.) showed no preference between its host plant and miscanthus. When assessed by electrical penetration graph technique, plant tissue probing activity by all three species always was characterized by pathway phases including potential drops that are typically associated to the transmission of noncirculative viruses. Phloem ingestion was observed in 5% of the polyphagous aphid individuals tested and in 20% of the R. padi tested. Aphids kept in clip-cages on miscanthus had a low survival rate and were unable to reproduce. These results demonstrate that miscanthus is not a suitable host for these three main aphid pest species but could act as a potential host for some viruses transmitted in a noncirculative manner and also in a circulative nonpropagative manner. The use of miscanthus as a barrier crop to limit the flow of aphid vectors and their phytoviruses is discussed.

  1. Vision in flying insects.

    Science.gov (United States)

    Egelhaaf, Martin; Kern, Roland

    2002-12-01

    Vision guides flight behaviour in numerous insects. Despite their small brain, insects easily outperform current man-made autonomous vehicles in many respects. Examples are the virtuosic chasing manoeuvres male flies perform as part of their mating behaviour and the ability of bees to assess, on the basis of visual motion cues, the distance travelled in a novel environment. Analyses at both the behavioural and neuronal levels are beginning to unveil reasons for such extraordinary capabilities of insects. One recipe for their success is the adaptation of visual information processing to the specific requirements of the behavioural tasks and to the specific spatiotemporal properties of the natural input.

  2. Beneficial Insects and Insect Pollinators on Milkweed in South Georgia

    Science.gov (United States)

    Insect pollinators are essential for the reproduction of more than two-thirds of the world’s crops, and beneficial insects play an important role in managing pest insects in agricultural farmscapes. These insects depend on nectar for their survival in these farmscapes. The flowers of tropical milkwe...

  3. Energetics of insect diapause.

    Science.gov (United States)

    Hahn, Daniel A; Denlinger, David L

    2011-01-01

    Managing metabolic resources is critical for insects during diapause when food sources are limited or unavailable. Insects accumulate reserves prior to diapause, and metabolic depression during diapause promotes reserve conservation. Sufficient reserves must be sequestered to both survive the diapause period and enable postdiapause development that may involve metabolically expensive functions such as metamorphosis or long-distance flight. Nutrient utilization during diapause is a dynamic process, and insects appear capable of sensing their energy reserves and using this information to regulate whether to enter diapause and how long to remain in diapause. Overwintering insects on a tight energy budget are likely to be especially vulnerable to increased temperatures associated with climate change. Molecular mechanisms involved in diapause nutrient regulation remain poorly known, but insulin signaling is likely a major player. We also discuss other possible candidates for diapause-associated nutrient regulation including adipokinetic hormone, neuropeptide F, the cGMP-kinase For, and AMPK.

  4. Annotated expressed sequence tags and xenobiotic detoxification in the aphid Myzus persicae (Sulzer)

    Institute of Scientific and Technical Information of China (English)

    C.C. FIGUEROA; N. PRUNIER-LETERME; C. RISPE; F. SEPULVEDA; E. FUENTES-CONTRERAS; B. SABATER-MUNOZ; J.-C. SIMON; D. TAGU

    2007-01-01

    Aphids (Hemiptera: Aphididae) are phytophagous insects that are importantagricultural pests. The enormous negative economic impacts caused by aphids worldwide arewell known, and are mostly due to their high multiplication rate and the transmission ofphytopathogenic viruses. Aphid management strategies mainly involve chemical treatmentswhich are pollutants and are increasingly inefficient, since aphids have developed multipleinsecticide-resistant mechanisms. Among the most economically important species is thegreen peach aphid Myzuspersicae Sulzer (Aphididae: Macrosiphini), which is able to colonizea wide range of host plants belonging to many different families, and transmits numerous plantviruses. Because of its large prevalence, M. persicae has been the target of massive insecticidetreatments; consequently, it has evolved several insecticide-resistant mechanisms. In thiswork, a collection of expressed genes from M. persicae is presented in order to identify putativegenes involved in xenobiotic detoxification. After cDNA cloning and sequencing, 959expressed sequence tags (EST) were annotated. Most sequences matched known genescorresponded to metabolism proteins (26%), ribosomal proteins (23%) and structural proteins(8%). Among them, several sequences corresponded to proteins putatively involved in sensing,degradation or detoxification of plant xenobiotic products.

  5. Beneficial Insects: Beetles

    OpenAIRE

    Hodgson, Erin W.; Patterson, Ron

    2007-01-01

    There are many beneficial beetles in Utah besides lady beetles or ladybugs. Beetles can significantly reduce common insect and weed problems and in some cases eliminate the need for chemical control. Examples of beneficial beetles include: ground beetles, rove beetles, tiger beetles and tortoise beetles. Many of these beetles are native to Utah, while others have been purposely introduced to help control damage from exotic insect and weed pests.

  6. Exploring Insect Vision

    Science.gov (United States)

    Damonte, Kathleen

    2005-01-01

    A fly is buzzing around in the kitchen. You sneak up on it with a flyswatter, but just as you get close to it, it flies away. What makes flies and other insects so good at escaping from danger? The fact that insects have eyesight that can easily detect moving objects is one of the things that help them survive. In this month's Science Shorts,…

  7. Insect immunology and hematopoiesis.

    Science.gov (United States)

    Hillyer, Julián F

    2016-05-01

    Insects combat infection by mounting powerful immune responses that are mediated by hemocytes, the fat body, the midgut, the salivary glands and other tissues. Foreign organisms that have entered the body of an insect are recognized by the immune system when pathogen-associated molecular patterns bind host-derived pattern recognition receptors. This, in turn, activates immune signaling pathways that amplify the immune response, induce the production of factors with antimicrobial activity, and activate effector pathways. Among the immune signaling pathways are the Toll, Imd, Jak/Stat, JNK, and insulin pathways. Activation of these and other pathways leads to pathogen killing via phagocytosis, melanization, cellular encapsulation, nodulation, lysis, RNAi-mediated virus destruction, autophagy and apoptosis. This review details these and other aspects of immunity in insects, and discusses how the immune and circulatory systems have co-adapted to combat infection, how hemocyte replication and differentiation takes place (hematopoiesis), how an infection prepares an insect for a subsequent infection (immune priming), how environmental factors such as temperature and the age of the insect impact the immune response, and how social immunity protects entire groups. Finally, this review highlights some underexplored areas in the field of insect immunobiology.

  8. Ability of Aphis gossypii and Myzus persicae to Transmit Cucumber mosaic virus in Single and Mixed Infection with Two Potyviruses to Zucchini Squash Eficiência dos afídeos Aphis gossypii e Myzus persicae na transmissão do Cucumber mosaic virus em infecção simples e mista com dois Potyvirus para abobrinha de moita

    OpenAIRE

    Zayame Vegette Pinto; Jorge Alberto Marques Rezende; Valdir Atsushi Yuki; Sônia Maria de Stefano Piedade

    2008-01-01

    The main objective of this work was to investigate the ability of Aphis gossypii and Myzus persicae to transmit Cucumber mosaic virus (CMV) singly and mixed with two potyviruses (Papaya ringspot virus - type W, PRSV-W and Zucchini yellow mosaic virus, ZYMV), to zucchini squash plants (Cucurbita pepo). The results showed that the potyviruses in general were more efficiently transmitted by both species of aphids as compared to CMV. The transmission of PRSV-W, ZYMV and CMV separately was more ef...

  9. Harpin-induced expression and transgenic overexpression of the phloem protein gene AtPP2-A1 in Arabidopsis repress phloem feeding of the green peach aphid Myzus persicae

    Directory of Open Access Journals (Sweden)

    Sun Weiwei

    2011-01-01

    Full Text Available Abstract Background Treatment of plants with HrpNEa, a protein of harpin group produced by Gram-negative plant pathogenic bacteria, induces plant resistance to insect herbivores, including the green peach aphid Myzus persicae, a generalist phloem-feeding insect. Under attacks by phloem-feeding insects, plants defend themselves using the phloem-based defense mechanism, which is supposed to involve the phloem protein 2 (PP2, one of the most abundant proteins in the phloem sap. The purpose of this study was to obtain genetic evidence for the function of the Arabidopsis thaliana (Arabidopsis PP2-encoding gene AtPP2-A1 in resistance to M. persicae when the plant was treated with HrpNEa and after the plant was transformed with AtPP2-A1. Results The electrical penetration graph technique was used to visualize the phloem-feeding activities of apterous agamic M. persicae females on leaves of Arabidopsis plants treated with HrpNEa and an inactive protein control, respectively. A repression of phloem feeding was induced by HrpNEa in wild-type (WT Arabidopsis but not in atpp2-a1/E/142, the plant mutant that had a defect in the AtPP2-A1 gene, the most HrpNEa-responsive of 30 AtPP2 genes. In WT rather than atpp2-a1/E/142, the deterrent effect of HrpNEa treatment on the phloem-feeding activity accompanied an enhancement of AtPP2-A1 expression. In PP2OETAt (AtPP2-A1-overexpression transgenic Arabidopsis thaliana plants, abundant amounts of the AtPP2-A1 gene transcript were detected in different organs, including leaves, stems, calyces, and petals. All these organs had a deterrent effect on the phloem-feeding activity compared with the same organs of the transgenic control plant. When a large-scale aphid population was monitored for 24 hours, there was a significant decrease in the number of aphids that colonized leaves of HrpNEa-treated WT and PP2OETAt plants, respectively, compared with control plants. Conclusions The repression in phloem-feeding activities of

  10. Herbivory by a Phloem-feeding insect inhibits floral volatile production.

    Directory of Open Access Journals (Sweden)

    Martin Pareja

    Full Text Available There is extensive knowledge on the effects of insect herbivory on volatile emission from vegetative tissue, but little is known about its impact on floral volatiles. We show that herbivory by phloem-feeding aphids inhibits floral volatile emission in white mustard Sinapis alba measured by gas chromatographic analysis of headspace volatiles. The effect of the Brassica specialist aphid Lipaphis erysimi was stronger than the generalist aphid Myzus persicae and feeding by chewing larvae of the moth Plutella xylostella caused no reduction in floral volatile emission. Field observations showed no effect of L. erysimi-mediated floral volatile emission on the total number of flower visits by pollinators. Olfactory bioassays suggested that although two aphid natural enemies could detect aphid inhibition of floral volatiles, their olfactory orientation to infested plants was not disrupted. This is the first demonstration that phloem-feeding herbivory can affect floral volatile emission, and that the outcome of interaction between herbivory and floral chemistry may differ depending on the herbivore's feeding mode and degree of specialisation. The findings provide new insights into interactions between insect herbivores and plant chemistry.

  11. Herbivory by a Phloem-feeding insect inhibits floral volatile production.

    Science.gov (United States)

    Pareja, Martin; Qvarfordt, Erika; Webster, Ben; Mayon, Patrick; Pickett, John; Birkett, Michael; Glinwood, Robert

    2012-01-01

    There is extensive knowledge on the effects of insect herbivory on volatile emission from vegetative tissue, but little is known about its impact on floral volatiles. We show that herbivory by phloem-feeding aphids inhibits floral volatile emission in white mustard Sinapis alba measured by gas chromatographic analysis of headspace volatiles. The effect of the Brassica specialist aphid Lipaphis erysimi was stronger than the generalist aphid Myzus persicae and feeding by chewing larvae of the moth Plutella xylostella caused no reduction in floral volatile emission. Field observations showed no effect of L. erysimi-mediated floral volatile emission on the total number of flower visits by pollinators. Olfactory bioassays suggested that although two aphid natural enemies could detect aphid inhibition of floral volatiles, their olfactory orientation to infested plants was not disrupted. This is the first demonstration that phloem-feeding herbivory can affect floral volatile emission, and that the outcome of interaction between herbivory and floral chemistry may differ depending on the herbivore's feeding mode and degree of specialisation. The findings provide new insights into interactions between insect herbivores and plant chemistry.

  12. Varying responses of insect herbivores to altered plant chemistry under organic and conventional treatments.

    Science.gov (United States)

    Staley, Joanna T; Stewart-Jones, Alex; Pope, Tom W; Wright, Denis J; Leather, Simon R; Hadley, Paul; Rossiter, John T; van Emden, Helmut F; Poppy, Guy M

    2010-03-07

    The hypothesis that plants supplied with organic fertilizers are better defended against insect herbivores than those supplied with synthetic fertilizers was tested over two field seasons. Organic and synthetic fertilizer treatments at two nitrogen concentrations were supplied to Brassica plants, and their effects on the abundance of herbivore species and plant chemistry were assessed. The organic treatments also differed in fertilizer type: a green manure was used for the low-nitrogen treatment, while the high-nitrogen treatment contained green and animal manures. Two aphid species showed different responses to fertilizers: the Brassica specialist Brevicoryne brassicae was more abundant on organically fertilized plants, while the generalist Myzus persicae had higher populations on synthetically fertilized plants. The diamondback moth Plutella xylostella (a crucifer specialist) was more abundant on synthetically fertilized plants and preferred to oviposit on these plants. Glucosinolate concentrations were up to three times greater on plants grown in the organic treatments, while foliar nitrogen was maximized on plants under the higher of the synthetic fertilizer treatments. The varying response of herbivore species to these strong differences in plant chemistry demonstrates that hypotheses on defence in organically grown crops have over-simplified the response of phytophagous insects.

  13. 百合病毒病媒介昆虫的研究%Studies on Insect Vectors on Lily Virus Disease

    Institute of Scientific and Technical Information of China (English)

    朱亚灵

    2013-01-01

    通过对百合病毒病媒介昆虫种类的调查与鉴定,研究其种群与百合病毒病病情间的关系。结果表明,桃蚜(Myzus persicae)是传播百合病毒病的主要种类;百合病毒病田间发病率与百株蚜量呈正相关(P<0.01, r=0.8729),说明百合种植地蚜虫数量较多,则病毒病严重;而蚜虫数量少,则病毒病发生较轻。因此控制迁入百合地的蚜虫数量是防治百合病毒病发生的关键措施。%Based on the investigation and identification of the species of insect vectors, the relationship of vectors and lily virus diseases was studied. The results showed that Myzus persicae is the most important vector. There was positive relationship between the incidence in the field and the amounts of vectors on one hundred plants. The correlation coefficient was 0.8729. This suggested that more amounts of vectors were, more severe the virus was. So reducing amounts of vectors is the essential measure for controlling lily virus disease.

  14. Insect bite reactions

    Directory of Open Access Journals (Sweden)

    Sanjay Singh

    2013-01-01

    Full Text Available Insects are a class of living creatures within the arthropods. Insect bite reactions are commonly seen in clinical practice. The present review touches upon the medically important insects and their places in the classification, the sparse literature on the epidemiology of insect bites in India, and different variables influencing the susceptibility of an individual to insect bites. Clinical features of mosquito bites, hypersensitivity to mosquito bites Epstein-Barr virus NK (HMB-EBV-NK disease, eruptive pseudoangiomatosis, Skeeter syndrome, papular pruritic eruption of HIV/AIDS, and clinical features produced by bed bugs, Mexican chicken bugs, assassin bugs, kissing bugs, fleas, black flies, Blandford flies, louse flies, tsetse flies, midges, and thrips are discussed. Brief account is presented of the immunogenic components of mosquito and bed bug saliva. Papular urticaria is discussed including its epidemiology, the 5 stages of skin reaction, the SCRATCH principle as an aid in diagnosis, and the recent evidence supporting participation of types I, III, and IV hypersensitivity reactions in its causation is summarized. Recent developments in the treatment of pediculosis capitis including spinosad 0.9% suspension, benzyl alcohol 5% lotion, dimethicone 4% lotion, isopropyl myristate 50% rinse, and other suffocants are discussed within the context of evidence derived from randomized controlled trials and key findings of a recent systematic review. We also touch upon a non-chemical treatment of head lice and the ineffectiveness of egg-loosening products. Knockdown resistance (kdr as the genetic mechanism making the lice nerves insensitive to permethrin is discussed along with the surprising contrary clinical evidence from Europe about efficacy of permethrin in children with head lice carrying kdr-like gene. The review also presents a brief account of insects as vectors of diseases and ends with discussion of prevention of insect bites and some

  15. Impact of plant growth-promoting rhizobacteria and natural enemies on Myzus persicae (Hemiptera: Aphididae) infestations in pepper.

    Science.gov (United States)

    Boutard-Hunt, Caroline; Smart, Christine D; Thaler, Jennifer; Nault, Brian A

    2009-12-01

    Management of green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), in bell pepper, Capsicum annuum L., was explored through a combination of plant growth-promoting rhizobacteria (PGPR) and endemic biological control in New York in 2006 and 2007. We hypothesized that by using PGPR-treated peppers 1) M. persicae infestations would be reduced via induced resistance, 2) natural enemies would be lured to plants through the elicitation of volatile organic compounds, and 3) yield amount and quality would be improved. Pepper seed was planted in soil containing the PGPR formulation BioYield or untreated soil. Plants were transplanted to field plots and then treated with an insecticide regimen designed to remove or conserve populations of natural enemies. Apterous aphids and natural enemies were counted weekly on plants and pepper fruit were harvested, graded and weighed three times. PGPR did not directly or indirectly reduce aphid densities in either year. In 2006, there were more natural enemies in PGPR-treated plots than untreated ones, but this was probably a density-dependent response to aphid densities rather than a response of natural enemies to volatiles from PGPR-treated plants. For the first harvest date in 2006, yield of all fruit grades, especially the premium Fancy Grade, was 1.7-2.3 times greater in PGPR-treated plots than in untreated plots. However, no differences in yield were observed for the other two harvest dates or overall yield in 2006; no differences in yield among treatments were detected in 2007. Our results suggest that PGPR will not significantly impact M. persicae infestations or natural enemy populations but could enhance yield and quality of pepper fruit in some years.

  16. Direct and Indirect Impacts of Infestation of Tomato Plant by Myzus persicae (Hemiptera: Aphididae) on Bemisia tabaci (Hemiptera: Aleyrodidae)

    Science.gov (United States)

    Tan, Xiao-Ling; Wang, Su; Ridsdill-Smith, James; Liu, Tong-Xian

    2014-01-01

    The impacts of infestation by the green peach aphid (Myzus persicae) on sweetpotato whitefly (Bemisia tabaci) settling on tomato were determined in seven separate experiments with whole plants and with detached leaves through manipulation of four factors: durations of aphid infestation, density of aphids, intervals between aphid removal after different durations of infestation and the time of whitefly release, and leaf positions on the plants. The results demonstrated that B. tabaci preferred to settle on the plant leaves that had not been infested by aphids when they had a choice. The plant leaves on which aphids were still present (direct effect) had fewer whiteflies than those previously infested by aphids (indirect effect). The whiteflies were able to settle on the plant which aphids had previously infested, and also could settle on leaves with aphids if no uninfested plants were available. Tests of direct factors revealed that duration of aphid infestation had a stronger effect on whitefly landing preference than aphid density; whitefly preference was the least when 20 aphids fed on the leaves for 72 h. Tests of indirect effects revealed that the major factor that affected whitefly preference for a host plant was the interval between the time of aphid removal after infestation and the time of whitefly release. The importance of the four factors that affected the induced plant defense against whiteflies can be arranged in the following order: time intervals between aphid removal and whitefly release > durations of aphid infestation > density of aphids > leaf positions on the plants. In conclusion, the density of aphid infestation and time for which they were feeding influenced the production of induced compounds by tomatoes, the whitefly responses to the plants, and reduced interspecific competition. PMID:24710393

  17. Systematic analysis of phloem-feeding insect-induced transcriptional reprogramming in Arabidopsis highlights common features and reveals distinct responses to specialist and generalist insects.

    Science.gov (United States)

    Foyer, Christine H; Verrall, Susan R; Hancock, Robert D

    2015-02-01

    Phloem-feeding insects (PFIs), of which aphids are the largest group, are major agricultural pests causing extensive damage to crop plants. In contrast to chewing insects, the nature of the plant response to PFIs remains poorly characterized. Scrutiny of the literature concerning transcriptional responses of model and crop plant species to PFIs reveals surprisingly little consensus with respect to the transcripts showing altered abundance following infestation. Nevertheless, core features of the transcriptional response to PFIs can be defined in Arabidopsis thaliana. This comparison of the PFI-associated transcriptional response observed in A. thaliana infested by the generalists Myzus persicae and Bemisia tabaci with the specialist Brevicoryne brassicae highlights the importance of calcium-dependent and receptor kinase-associated signalling. We discuss these findings within the context of the complex cross-talk between the different hormones regulating basal immune response mechanisms in plants. We identify PFI-responsive genes, highlighting the importance of cell wall-associated kinases in plant-PFI interactions, as well as the significant role of kinases containing the domain of unknown function 26. A common feature of plant-PFI interaction is enhanced abundance of transcripts encoding WRKY transcription factors. However, significant divergence was observed with respect to secondary metabolism dependent upon the insect attacker. Transcripts encoding enzymes and proteins associated with glucosinolate metabolism were decreased following attack by the generalist M. persicae but not by the specialist B. brassicae. This analysis provides a comprehensive overview of the molecular patterns associated with the plant response to PFIs and suggests that plants recognize and respond to perturbations in the cell wall occurring during PFI infestation.

  18. Migration strategies of insects.

    Science.gov (United States)

    Dingle, H

    1972-03-24

    Physiological and ecological results from a variety of species are consistent with what seem to be valid general statements concerning insect migration. These are as follows: (i)During migration locomotory functions are enhanced and vegetative functions such as feeding and reproduction are suppressed. (ii) Migration usually occurs prereproductively in the life of the adult insect (the oogenesis-flight syndrome). (iii)Since migrant individuals are usually prereproductive, their reproductive values, and hence colonizing abilities, are at or near maximum. (iv) Migrants usually reside in temporary habitats. (v)Migrants have a high potential for population increase, r, which is also advantageous for colonizers. (vi)Both the physiological and ecological parameters of migration are modifiable by environmental factors (that is, phenotypically modifiable)to suit the prevailing conditions. Taken together, these criteria establish a comprehensive theory and adumbrate the basic strategy for migrant insects. This basic strategy is modified to suit the ecological requirements of individual species. Comparative studies of these modifications are of considerable theoretical and practical interest, the more so since most economically important insects are migrants. No satisfactory general statements can as yet be made with respect to the genotype and migration. Certainly we expect colonizing populiations to possess genotypes favoring a high r, but genotypic variation in r depends on the heritabilities of life table statistics, and such measurements are yet to be made (10, 53). The fact that flight duration can be increased by appropriate selection in Oncopeltus fasciatus, and the demonstration of additive genetic variance for this trait in Lygaeus kalmii, suggest that heritability studies of migratory behavior would also be worth pursuing. Most interesting of course, will be possible genetic correlations between migration and life history parameters. Also, migration often

  19. Behavioral Immunity in Insects

    Directory of Open Access Journals (Sweden)

    Thierry Lefèvre

    2012-08-01

    Full Text Available Parasites can dramatically reduce the fitness of their hosts, and natural selection should favor defense mechanisms that can protect hosts against disease. Much work has focused on understanding genetic and physiological immunity against parasites, but hosts can also use behaviors to avoid infection, reduce parasite growth or alleviate disease symptoms. It is increasingly recognized that such behaviors are common in insects, providing strong protection against parasites and parasitoids. We review the current evidence for behavioral immunity in insects, present a framework for investigating such behavior, and emphasize that behavioral immunity may act through indirect rather than direct fitness benefits. We also discuss the implications for host-parasite co-evolution, local adaptation, and the evolution of non-behavioral physiological immune systems. Finally, we argue that the study of behavioral immunity in insects has much to offer for investigations in vertebrates, in which this topic has traditionally been studied.

  20. Insect Repellents: Protect Your Child from Insect Bites

    Science.gov (United States)

    ... Español Text Size Email Print Share Choosing an Insect Repellent for Your Child Page Content Mosquitoes, biting ... sunscreen needs to be reapplied often. Reactions to Insect Repellents If you suspect that your child is ...

  1. Transcriptomic responses of the aphid Myzus persicae nicotianae Blackman (Hemiptera: Aphididae to insecticides: Analyses in the single Chilean clone of the tobacco aphid

    Directory of Open Access Journals (Sweden)

    Marco Cabrera-Brandt

    2014-04-01

    Full Text Available The tobacco aphid Myzus persicae nicotianae Blackman is a subspecies of the highly polyphagous and agricultural pest Myzus persicae (Sulzer. For its control, insecticide applications are widely used, but resistance to numerous molecules has been reported, displaying at least three insecticide resistance mechanisms, including: (i elevated carboxylesterases (E-Carb, (ii modification of the acetylcholinesterase (MACE, and (iii kdr and super-kdr insensitivity mutations. In Chile, populations of the tobacco aphid are characterized by the presence of a single predominant clone, which is also present in high proportions in other countries of the Americas. This aphid clone exhibits low levels of carboxylesterase activity and is kdr susceptible, but the MACE mechanism of insecticide resistance has not been studied. In order to characterize the tobacco aphid in terms of the MACE mechanism and to identify a preliminary group of aphid genes putatively involved in insecticide resistance, a cDNA microarray was used to study the transcriptomic responses when aphids are sprayed with a carbamate insecticide. The single Chilean clone of the tobacco aphid was characterized as MACE susceptible, but we found 38 transcripts significantly regulated by insecticide exposure (13 up- and 25 down-regulated genes. The expression of six of them was validated by qRT-PCR experiments at several time points (6, 12, 18, 24, 30, 36, and 42 h after insecticide application. This mutational and transcriptomic characterization of the tobacco aphid responding to insecticide spray opens new hypotheses in the understanding of the molecular mechanisms underlying insecticide resistance.

  2. Microsatellite isolation, linkage group identification and determination of recombination frequency in the peach-potato aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae).

    Science.gov (United States)

    Sloane, M A; Sunnucks, P; Wilson, A C; Hales, D F

    2001-06-01

    Fifteen polymorphic microsatellite markers were used to establish linkage groups and relative rates of recombination in male and female Myzus persicae (Sulzer) (Hemiptera: Aphididae) (peach-potato aphid). We cloned nine markers from M. persicae and for these we report primer sequences and levels of allelic diversity and heterozygosity in four Australian M. persicae populations. Of the remaining six loci, four loci, also cloned from M. persicae, were obtained from G. Malarky (Natural History Museum, London) and two loci from Sitobion miscanthi were used. Additionally, the primer sequences of locus M77, a locus monomorphic in M. persicae but polymorphic in the closely related Myzus antirrhinii, are presented. Eleven of the 15 polymorphic markers were autosomal and four were X-linked. A linkage analysis was performed on a European pedigree of aphids containing five families with between seven and 11 offspring each. There was no linkage between any loci in females. In males, several pairwise comparisons yielded no recombinant offspring. With the exception of locus M40, these observations were supported in a linkage analysis performed on larger families produced from Australian M. persicae crosses. Locus M40 showed segregation consistent with involvement in a translocation between autosomes 1 and 3 in European samples but not in the Australian samples. From the Australian crosses we report an absence of recombination in males but high recombination rates in females. One X chromosome and four autosomal linkage groups were identified and tentatively assigned to chromosomes. The relevance of achiasmate meiosis to the evolution of sex is discussed.

  3. Mitochondrial COI and morphological evidence for host specificity of the black cherry aphids Myzus cerasi (Fabricius, 1775 collected from different cherry tree species in Europe (Hemiptera, Aphididae

    Directory of Open Access Journals (Sweden)

    Rimantas Rakauskas

    2014-03-01

    Full Text Available Partial sequences of the mitochondrial COI gene of forty eight European and two Turkish population samples of Myzus cerasi from different winter hosts (Prunus spp. were subjected to phylogenetic analyses. The analysed M. cerasi samples emerged as paraphyletic relative to a Myzus borealis sample used as an out-group, and formed two major clades in neighbor joining, maximum parsimony, maximum likelihood and Bayesian inference trees, corresponding to subspecies living specifically on Prunus avium and P. cerasus. Multivariate discriminant analysis (method of canonical variates was applied to find out if morphological variation of samples correlated with mitochondrial COI and host plant information. Mean scores on the first two canonical variables clustered samples fully in accordance with their COI haplotypes and host plants confirming the existence of two morphologically similar winter host - specific subspecies of M.cerasi in Europe. No single morphological character enabled satisfactory discrimination between apterous viviparous females of the two subspecies. A three-character linear discriminant function enabled 92.37% correct identification of apterous viviparous females of M. cerasi cerasi (n=118 and 93.64% of M. cerasi pruniavium (n=110. A key for the morphological identification of the two subspecies is presented and their taxonomic status is discussed.

  4. 长沙烟区天敌昆虫物种多样性及其与主要害虫的消长动态%Species Diversity of Natural Enemy Insects and Population Dynamic of Main Pest Insects in Changsha Tobacco Areas

    Institute of Scientific and Technical Information of China (English)

    曾维爱; 郭婷; 李密; 谭琳; 周刚; 李帆; 蔡海林; 何振; 胡秋龙; 颜学武

    2016-01-01

    Species diversity of natural enemy insects and population dynamic of main pest insects in Changsha tobacco areas were studied through wulti-site investigation and focused monitoring from 2014 to 2015. The results showed that 18 species of natural enemy insects were observed, including 5 dominant species, includingHarmonia axyridis, Propylaea japonica,Coccinella septempunctata, Paederus fuscipes andCampoletis chlorideae. The numbers of species and individuals of natural enemy insects were small, and the control capacity against main pest insects was weak. Species diversity of natural enemy insects was the highest in June. The relationship betweenMyzus persicae and its natural enemy insects exhibited a hysteresis phenomenon, while the relationship between Lepidoptera pests and natural enemy insects exhibited a following phenomenon.%采用多点调查和集中监测的方法对长沙烟区烟田天敌昆虫物种多样性及其与主要害虫的消长规律进行了调查和研究。共记录烟田害虫天敌昆虫18种,优势种5种,包括异色瓢虫、龟纹瓢虫、七星瓢虫、隐翅虫和棉铃虫齿唇姬蜂;天敌物种个体数相对较少,对烟田主要害虫的控制能力较弱;烟田天敌昆虫物种多样性系数以每年的6月最大;烟蚜及其天敌发生规律呈滞后现象,而鳞翅目害虫与其天敌主要呈跟随现象。

  5. Protecting Yourself from Stinging Insects

    Science.gov (United States)

    ... plants when possible. ■■ Keep work areas clean. Some insects are attracted to discarded food. ■■ Remain calm and still if a single stinging insect is flying around. (Swatting may cause it to ...

  6. Eicosanoid actions in insect immunity

    Science.gov (United States)

    Insects express three lines of protection from infections and invasions. Their cuticles and peritrophic membranes are physical barriers. Infections and invasions are quickly recognized within insect bodies; recognition launches two lines of innate immune reactions. Humoral reactions involve induc...

  7. Sterol metabolism of insects

    NARCIS (Netherlands)

    Ritter, F.J.; Wientjens, W.H.J.M.

    1967-01-01

    This article surveys the present knowledge of the sterol metabolism of insects. It is emphasized that a high degree of purity of the dietary sterols and the climination of the influence of symbionts are essential to present ambiguity in interpreting results. It is pointed out that a sharp distinctio

  8. Recycled Insect Models

    Science.gov (United States)

    Rule, Audrey C.; Meyer, Mary Ann

    2007-01-01

    This article presents an engaging activity in which high school students use a dichotomous key to guide the creation and classification of model insects from recycled plastic lids and containers. Besides teaching the use of a dichotomous key and the effect of evolutionary descent upon groupings of organisms, this activity focuses on an…

  9. Olfactory signaling in insects.

    Science.gov (United States)

    Wicher, Dieter

    2015-01-01

    The detection of volatile chemical information in insects is performed by three types of olfactory receptors, odorant receptors (ORs), specific gustatory receptor (GR) proteins for carbon dioxide perception, and ionotropic receptors (IRs) which are related to ionotropic glutamate receptors. All receptors form heteromeric assemblies; an OR complex is composed of an odor-specific OrX protein and a coreceptor (Orco). ORs and GRs have a 7-transmembrane topology as for G protein-coupled receptors, but they are inversely inserted into the membrane. Ligand-gated ion channels (ionotropic receptors) and ORs operate as IRs activated by volatile chemical cues. ORs are evolutionarily young receptors, and they first appear in winged insects and seem to be evolved to allow an insect to follow sparse odor tracks during flight. In contrast to IRs, the ORs can be sensitized by repeated subthreshold odor stimulation. This process involves metabotropic signaling. Pheromone receptors are especially sensitive and require an accessory protein to detect the lipid-derived pheromone molecules. Signaling cascades involved in pheromone detection depend on intensity and duration of stimuli and underlie a circadian control. Taken together, detection and processing of volatile information in insects involve ionotropic as well as metabotropic mechanisms. Here, I review the cellular signaling events associated with detection of cognate ligands by the different types of odorant receptors.

  10. Insects and sex

    NARCIS (Netherlands)

    Beukeboom, Leo

    2005-01-01

    Most organisms reproduce sexually, but the evolution of sexual reproduction is not yet well understood. Sexual reproduction leads to new variation and adaptations to the environment, but sex is also costly. Some insects reproduce without sex through parthenogenesis or paedogenesis. Almost all sexual

  11. Broadening insect gastronomy

    DEFF Research Database (Denmark)

    Halloran, Afton Marina Szasz; Münke, Christopher; Vantomme, Paul;

    2015-01-01

    In recent years there has been a trend among chefs to diversify their ingredients and techniques, drawing inspiration from other cultures and creating new foods by blending this knowledge with the flavours of their local region. Edible insects, with their plethora of taste, aromatic, textural...

  12. Colour constancy in insects.

    Science.gov (United States)

    Chittka, Lars; Faruq, Samia; Skorupski, Peter; Werner, Annette

    2014-06-01

    Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far tested. Especially the pollinating insects offer a remarkable opportunity to study the ecological significance of colour constancy since they spend much of their adult lives identifying and choosing between colour targets (flowers) under continuously changing ambient lighting conditions. In bees, whose colour vision is best studied among the insects, the compensation provided by colour constancy is only partial and its efficiency depends on the area of colour space. There is no evidence for complete 'discounting' of the illuminant in bees, and the spectral composition of the light can itself be used as adaptive information. In patchy illumination, bees adjust their spatial foraging to minimise transitions between variously illuminated zones. Modelling allows the quantification of the adaptive benefits of various colour constancy mechanisms in the economy of nature. We also discuss the neural mechanisms and cognitive operations that might underpin colour constancy in insects.

  13. Investigation--Insects!

    Science.gov (United States)

    Fay, Janice

    2000-01-01

    Presents activities on insects for second grade students. In the first activity, students build a butterfly garden. In the second activity, students observe stimuli reactions with mealworms in the larval stage. Describes the assessment process and discusses the effects of pollution on living things. (YDS)

  14. Resistance to Insecticides in Insects

    OpenAIRE

    2005-01-01

    In recent years, the frequent usage of insecticides in struggle aganist insects, has caused development of resistance to those chemicals in insects. The increase in dosage of insecticide used due to development of resistance in insects, causes important problems in terms of environment and human health. This study includes topics such as insecticides which are used frequently in insect struggle, insecticide resistant types, genetic changes posing resistance, enzymes of resistance and resistan...

  15. The promise of insect genomics

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, Cornelis J P; Cazzamali, Giuseppe; Williamson, Michael

    2007-01-01

    Insects are the largest animal group in the world and are ecologically and economically extremely important. This importance of insects is reflected by the existence of currently 24 insect genome projects. Our perspective discusses the state-of-the-art of these genome projects and the impacts tha...

  16. Activity of selected neonicotinoids and dicrotophos on nontarget arthropods in cotton: implications in insect management.

    Science.gov (United States)

    Kilpatrick, A L; Hagerty, A M; Turnipseed, S G; Sullivan, M J; Bridges, W C

    2005-06-01

    Certain neonicotinoids are used in cotton, Gossypium hirsutum (L.), to control various piercing-sucking pests. We conducted field studies using three neonicotinoids (acetamiprid, thiamethoxam, and imidacloprid) and an organophosphate (dicrotophos) to assess the activity of these insecticides against nontarget arthropods, particularly predators, and to determine the potential economic consequences of such activity. Mortality among populations of the big-eyed bug, Geocoris punctipes (Say), and the red imported fire ant, Solenopsis invicta Buren, was highest after thiamethoxam and dicrotophos treatments. Numbers of arachnids were consistently lower after dicrotophos treatments, whereas none of the neonicotinoids caused appreciable mortality. Total predators in pooled data from five separate studies revealed that numbers, compared with untreated plots, were reduced by -75% in dicrotophos, 55-60% in thiamethoxam, and only 30% in both acetamiprid and imidacloprid plots. Acetamiprid and thiamethoxam exhibited significant mortality against field-deposited eggs of bollworm, Helicoverpa zea (Boddie). Both thiamethoxam and dicrotophos plots exhibited bollworm numbers that were approximately three times higher than treatment thresholds (three per 100 plants), whereas numbers in untreated plots were below threshold levels. In one study on Bt cotton, a significant negative correlation was observed between numbers of predators and bollworm larvae. Results demonstrated that neonicotinoids differ in activity against predaceous arthropods and bollworm eggs and that high predator mortality can result in resurgence of bollworm larvae and additional insecticide costs.

  17. Venoms of Heteropteran Insects: A Treasure Trove of Diverse Pharmacological Toolkits.

    Science.gov (United States)

    Walker, Andrew A; Weirauch, Christiane; Fry, Bryan G; King, Glenn F

    2016-02-12

    The piercing-sucking mouthparts of the true bugs (Insecta: Hemiptera: Heteroptera) have allowed diversification from a plant-feeding ancestor into a wide range of trophic strategies that include predation and blood-feeding. Crucial to the success of each of these strategies is the injection of venom. Here we review the current state of knowledge with regard to heteropteran venoms. Predaceous species produce venoms that induce rapid paralysis and liquefaction. These venoms are powerfully insecticidal, and may cause paralysis or death when injected into vertebrates. Disulfide-rich peptides, bioactive phospholipids, small molecules such as N,N-dimethylaniline and 1,2,5-trithiepane, and toxic enzymes such as phospholipase A2, have been reported in predatory venoms. However, the detailed composition and molecular targets of predatory venoms are largely unknown. In contrast, recent research into blood-feeding heteropterans has revealed the structure and function of many protein and non-protein components that facilitate acquisition of blood meals. Blood-feeding venoms lack paralytic or liquefying activity but instead are cocktails of pharmacological modulators that disable the host haemostatic systems simultaneously at multiple points. The multiple ways venom is used by heteropterans suggests that further study will reveal heteropteran venom components with a wide range of bioactivities that may be recruited for use as bioinsecticides, human therapeutics, and pharmacological tools.

  18. Venoms of Heteropteran Insects: A Treasure Trove of Diverse Pharmacological Toolkits

    Directory of Open Access Journals (Sweden)

    Andrew A. Walker

    2016-02-01

    Full Text Available The piercing-sucking mouthparts of the true bugs (Insecta: Hemiptera: Heteroptera have allowed diversification from a plant-feeding ancestor into a wide range of trophic strategies that include predation and blood-feeding. Crucial to the success of each of these strategies is the injection of venom. Here we review the current state of knowledge with regard to heteropteran venoms. Predaceous species produce venoms that induce rapid paralysis and liquefaction. These venoms are powerfully insecticidal, and may cause paralysis or death when injected into vertebrates. Disulfide-rich peptides, bioactive phospholipids, small molecules such as N,N-dimethylaniline and 1,2,5-trithiepane, and toxic enzymes such as phospholipase A2, have been reported in predatory venoms. However, the detailed composition and molecular targets of predatory venoms are largely unknown. In contrast, recent research into blood-feeding heteropterans has revealed the structure and function of many protein and non-protein components that facilitate acquisition of blood meals. Blood-feeding venoms lack paralytic or liquefying activity but instead are cocktails of pharmacological modulators that disable the host haemostatic systems simultaneously at multiple points. The multiple ways venom is used by heteropterans suggests that further study will reveal heteropteran venom components with a wide range of bioactivities that may be recruited for use as bioinsecticides, human therapeutics, and pharmacological tools.

  19. Longevidade e parâmetros reprodutivos de Myzus persicae (Sulzer, 1776 (Hemiptera: Aphididae sobre berinjela em diferentes temperaturas Longevity and reproductive parameters of Myzus persicae (Sulzer, 1776 (Hemiptera: Aphididae on eggplant at different temperatures

    Directory of Open Access Journals (Sweden)

    Marcos Doniseti Michelotto

    2005-08-01

    Full Text Available O afídeo Myzus persicae (Sulzer, 1776 (Hemiptera: Aphididae é uma das principais pragas de diversas culturas em condições de campo ou em cultivo protegido. Este trabalho teve por objetivo avaliar o efeito de diferentes temperaturas na longevidade e nos aspectos reprodutivos de M. persicae sobre berinjela (Solanum melongena L.. O experimento foi conduzido sob condições controladas de temperatura (15, 20, 25 e 30°C, umidade relativa do ar (70 ± 10% e fotofase (12 horas. As unidades experimentais consistiram de placas de Petri contendo ágar-água solidificado (1%. Nestas placas, os afídeos foram mantidos individualmente sobre os discos foliares de berinjela (3 cm de diâmetro em uma das temperaturas (tratamentos, com 25 repetições. Foram determinadas as curvas mais ajustadas aos parâmetros biológicos de M. persicae, suas equações de regressão e os respectivos coeficientes de determinação (R². A temperatura influenciou todos os parâmetros avaliados. As durações dos períodos pré-reprodutivo e reprodutivo de M. persicae variaram de 0,46 dia (25°C a 1,12 dia (15°C e de 3,89 dias (25°C a 19,11 dias (15°C, respectivamente. A fecundidade total e diária foi de 17,63 ninfas/fêmea e 4,38 ninfas/fêmea/dia a 25°C; 43,63 ninfas/fêmea e 4,34 ninfas/fêmea/dia a 20°C; 60,65 ninfas/fêmea e 3,15 ninfas/fêmea/dia a 15°C. A 30°C, não houve reprodução. A duração do período pós-reprodutivo variou de 0,89 dia (25°C a 3,72 dias (15°C. A longevidade do afídeo diminuiu com o aumento da temperatura, de 23,95 dias (15°C para 5,06 dias (25°C. Temperaturas entre 15 e 20°C são mais favoráveis a M. persicae.The aphid Myzus persicae (Sulzer, 1776 (Hemiptera: Aphididae is one of the main pests in a number of crops both under field and protected conditions. The objective of this work was to study the effect of temperature on longevity and reproductive parameters of M. persicae on eggplant (Solanum melongena L.. The experiment

  20. Evaluating insect-microbiomes at the plant-insect interface.

    Science.gov (United States)

    Casteel, Clare L; Hansen, Allison K

    2014-07-01

    Plants recognize biotic challengers and respond with the appropriate defense by utilizing phytohormone signaling and crosstalk. Despite this, microbes and insects have evolved mechanisms that compromise the plant surveillance system and specific defenses, thus ensuring successful colonization. In nature, plants do not experience insect herbivores and microbes in isolation, but in combination. Over time, relationships have developed between insects and microbes, varying on a continuum from no-relationship to obligate relationships that are required for both organisms to survive. While many reviews have examined plant-insect and plant-microbe interactions and the mechanisms of plant defense, few have considered the interface where microbes and insects may overlap, and synergies may develop. In this review, we critically evaluate the requirements for insect-associated microbes to develop synergistic relationships with their hosts, and we mechanistically discuss how some of these insect-associated microbes can target or modify host plant defenses. Finally, by using bioinformatics and the recent literature, we review evidence for synergies in insect-microbe relationships at the interface of plant-insect defenses. Insect-associated microbes can influence host-plant detection and/or signaling through phytohormone synthesis, conserved microbial patterns, and effectors, however, microbes associated with insects must be maintained in the environment and located in opportunistic positions.

  1. RNAi: future in insect management.

    Science.gov (United States)

    Burand, John P; Hunter, Wayne B

    2013-03-01

    RNA interference is a post- transcriptional, gene regulation mechanism found in virtually all plants and animals including insects. The demonstration of RNAi in insects and its successful use as a tool in the study of functional genomics opened the door to the development of a variety of novel, environmentally sound approaches for insect pest management. Here the current understanding of the biogenesis of the two RNAi classes in insects is reviewed. These are microRNAs (miRNAs) and short interfering RNAs (siRNAs). Several other key approaches in RNAi -based for insect control, as well as for the prevention of diseases in insects are also reviewed. The problems and prospects for the future use of RNAi in insects are presented.

  2. Cleptobiosis in Social Insects

    Directory of Open Access Journals (Sweden)

    Michael D. Breed

    2012-01-01

    Full Text Available In this review of cleptobiosis, we not only focus on social insects, but also consider broader issues and concepts relating to the theft of food among animals. Cleptobiosis occurs when members of a species steal food, or sometimes nesting materials or other items of value, either from members of the same or a different species. This simple definition is not universally used, and there is some terminological confusion among cleptobiosis, cleptoparasitism, brood parasitism, and inquilinism. We first discuss the definitions of these terms and the confusion that arises from varying usage of the words. We consider that cleptobiosis usually is derived evolutionarily from established foraging behaviors. Cleptobionts can succeed by deception or by force, and we review the literature on cleptobiosis by deception or force in social insects. We focus on the best known examples of cleptobiosis, the ectatommine ant Ectatomma ruidum, the harvester ant Messor capitatus, and the stingless bee Lestrimellita limão. Cleptobiosis is facilitated either by deception or physical force, and we discuss both mechanisms. Part of this discussion is an analysis of the ecological implications (competition by interference and the evolutionary effects of cleptobiosis. We conclude with a comment on how cleptobiosis can increase the risk of disease or parasite spread among colonies of social insects.

  3. Polyphenism in insects.

    Science.gov (United States)

    Simpson, Stephen J; Sword, Gregory A; Lo, Nathan

    2011-09-27

    Polyphenism is the phenomenon where two or more distinct phenotypes are produced by the same genotype. Examples of polyphenism provide some of the most compelling systems for the study of epigenetics. Polyphenisms are a major reason for the success of the insects, allowing them to partition life history stages (with larvae dedicated to feeding and growth, and adults dedicated to reproduction and dispersal), to adopt different phenotypes that best suit predictable environmental changes (seasonal morphs), to cope with temporally heterogeneous environments (dispersal morphs), and to partition labour within social groups (the castes of eusocial insects). We survey the status of research on some of the best known examples of insect polyphenism, in each case considering the environmental cues that trigger shifts in phenotype, the neurochemical and hormonal pathways that mediate the transformation, the molecular genetic and epigenetic mechanisms involved in initiating and maintaining the polyphenism, and the adaptive and life-history significance of the phenomenon. We conclude by highlighting some of the common features of these examples and consider future avenues for research on polyphenism.

  4. Edible insects are the future?

    Science.gov (United States)

    van Huis, Arnold

    2016-08-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of low greenhouse gas emissions, high feed conversion efficiency, low land use, and their ability to transform low value organic side streams into high value protein products. More than 2000 insect species are eaten mainly in tropical regions. The role of edible insects in the livelihoods and nutrition of people in tropical countries is discussed, but this food source is threatened. In the Western world, there is an increasing interest in edible insects, and examples are given. Insects as feed, in particular as aquafeed, have a large potential. Edible insects have about the same protein content as conventional meat and more PUFA. They may also have some beneficial health effects. Edible insects need to be processed and turned into palatable dishes. Food safety may be affected by toxicity of insects, contamination with pathogens, spoilage during conservation and allergies. Consumer attitude is a major issue in the Western world and a number of strategies are proposed to encourage insect consumption. We discuss research pathways to make insects a viable sector in food and agriculture: an appropriate disciplinary focus, quantifying its importance, comparing its nutritional value to conventional protein sources, environmental benefits, safeguarding food safety, optimising farming, consumer acceptance and gastronomy.

  5. Experimental epizootiology of Zoophthora anhuiensis (Entomophthorales) against Myzus persicae (Homoptera: Aphididae) with a description of a modified Gompertz model for aphid epizootics.

    Science.gov (United States)

    Feng, Ming-Guang; Li, Hui-Ping

    2003-11-01

    Epizootiological features of Zoophthora anhuiensis, a fungal pathogen specific to aphids in southern China, were studied in six aptera colonies of Myzus persicae at 16 regimes of temperature (T = 10, 15, 20 and 25 degrees C) and relative humidity (H = 90%, 95%, 98% and 100% RH) with initially infected proportion (Ip) of 0.5 in experiment (Expt) 1 or at a fixed regime of 15 degrees C and 100% RH with a variable Ip of 0.17-1.00 in Expt 2. Mycosis-caused mortalities (Mp) varied with aphid densities (D) over time after colony initiation (t) were well fitted to a Gompertz growth model modified to include the variables T, H, Ip and D in the form of Mp = 91.72exp[-5.282exp[-(0.0095T + 0.0128H/T-0.5407D2/H)t

  6. Green peach aphid infestation induces Arabidopsis PHYTOALEXIN-DEFICIENT4 expression at site of insect feeding.

    Science.gov (United States)

    Louis, Joe; Mondal, Hossain A; Shah, Jyoti

    2012-11-01

    The Arabidopsis thaliana PHYTOALEXIN-DEFICIENT4 (PAD4) protein, which has homology to lipases, is required for phloem-based resistance against the green peach aphid (GPA; Myzus persicae Sülzer). PAD4 modulates antibiotic and antixenotic defenses against GPA. PAD4 in conjunction with its interacting partner ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) also functions in basal resistance to bacterial and oomycete pathogens by promoting salicylic acid (SA)-dependent and SA-independent defenses. By contrast, neither EDS1 nor SA is required for PAD4-controlled defense against GPA. Distinct molecular activities of PAD4 are involved in different aspects of Arabidopsis defense against GPA and pathogens. Histochemical analysis of plants containing a PAD4p:GUS chimera, which expresses the GUS reporter from the PAD4 promoter, indicated strong PAD4 promoter activity at the site of penetration of the vasculature by the insect stylet. GUS activity was also observed in non-vascular tissues of GPA-infested leaves, thus raising the possibility that a combination of distinct PAD4 activities in vascular and non-vascular tissues contribute to Arabidopsis defense against GPA.

  7. Two Volatile Organic Compounds Trigger Plant Self-Defense against a Bacterial Pathogen and a Sucking Insect in Cucumber under Open Field Conditions

    Directory of Open Access Journals (Sweden)

    Choong-Min Ryu

    2013-05-01

    Full Text Available Systemic acquired resistance (SAR is a plant self-defense mechanism against a broad-range of pathogens and insect pests. Among chemical SAR triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. However, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open field, their negative effects on plant growth, and their inconsistent levels of effectiveness. Here, we demonstrate the effectiveness of volatile organic compound (VOC-mediated induced resistance against both the bacterial angular leaf spot pathogen, Pseudononas syringae pv. lachrymans, and the sucking insect aphid, Myzus persicae, in the open field. Using the VOCs 3-pentanol and 2-butanone where fruit yields increased gave unexpectedly, a significant increase in the number of ladybird beetles, Coccinella septempunctata, a natural enemy of aphids. The defense-related gene CsLOX was induced by VOC treatment, indicating that triggering the oxylipin pathway in response to the emission of green leaf volatiles can recruit the natural enemy of aphids. These results demonstrate that VOCs may help prevent plant disease and insect damage by eliciting induced resistance, even in open fields.

  8. Two volatile organic compounds trigger plant self-defense against a bacterial pathogen and a sucking insect in cucumber under open field conditions.

    Science.gov (United States)

    Song, Geun Cheol; Ryu, Choong-Min

    2013-05-08

    Systemic acquired resistance (SAR) is a plant self-defense mechanism against a broad-range of pathogens and insect pests. Among chemical SAR triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. However, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open field, their negative effects on plant growth, and their inconsistent levels of effectiveness. Here, we demonstrate the effectiveness of volatile organic compound (VOC)-mediated induced resistance against both the bacterial angular leaf spot pathogen, Pseudononas syringae pv. lachrymans, and the sucking insect aphid, Myzus persicae, in the open field. Using the VOCs 3-pentanol and 2-butanone where fruit yields increased gave unexpectedly, a significant increase in the number of ladybird beetles, Coccinella septempunctata, a natural enemy of aphids. The defense-related gene CsLOX was induced by VOC treatment, indicating that triggering the oxylipin pathway in response to the emission of green leaf volatiles can recruit the natural enemy of aphids. These results demonstrate that VOCs may help prevent plant disease and insect damage by eliciting induced resistance, even in open fields.

  9. Ability of Aphis gossypii and Myzus persicae to Transmit Cucumber mosaic virus in Single and Mixed Infection with Two Potyviruses to Zucchini Squash Eficiência dos afídeos Aphis gossypii e Myzus persicae na transmissão do Cucumber mosaic virus em infecção simples e mista com dois Potyvirus para abobrinha de moita

    Directory of Open Access Journals (Sweden)

    Zayame Vegette Pinto

    2008-06-01

    Full Text Available The main objective of this work was to investigate the ability of Aphis gossypii and Myzus persicae to transmit Cucumber mosaic virus (CMV singly and mixed with two potyviruses (Papaya ringspot virus - type W, PRSV-W and Zucchini yellow mosaic virus, ZYMV, to zucchini squash plants (Cucurbita pepo. The results showed that the potyviruses in general were more efficiently transmitted by both species of aphids as compared to CMV. The transmission of PRSV-W, ZYMV and CMV separately was more efficient than in mixture.O objetivo desse trabalho foi estudar a eficiência de Aphis gossypii e Myzus persicae na transmissão do vírus do mosaico do pepino (Cucumber mosaic virus, CMV, isoladamente e em mistura com duas espécies de potyvirus (Vírus do mosaico do mamoeiro = Papaya ringspot virus - type W, PRSV-W e Vírus do mosaico amarelo da abobrinha = Zucchini yellow mosaic virus, ZYMV, para planta-testes de abobrinha de moita (Cucurbita pepo. Os dois potyvirus em geral foram transmitidos com mais eficiência pelas duas espécies de afídeos do que o CMV. A transmissão do PRSV-W, ZYMV e CMV, separadamente, foi mais eficiente do que em mistura.

  10. 1977 Kansas Field Crop Insect Control Recommendations.

    Science.gov (United States)

    Brooks, Leroy; Gates, Dell E.

    This publication is prepared to aid producers in selecting methods of insect population management that have proved effective under Kansas conditions. Topics covered include insect control on alfalfa, soil insects attacking corn, insects attacking above-ground parts of corn, and sorghum, wheat, and soybean insect control. The insecticides…

  11. Hydrodynamics of insect spermatozoa

    Science.gov (United States)

    Pak, On Shun; Lauga, Eric

    2010-11-01

    Microorganism motility plays important roles in many biological processes including reproduction. Many microorganisms propel themselves by propagating traveling waves along their flagella. Depending on the species, propagation of planar waves (e.g. Ceratium) and helical waves (e.g. Trichomonas) were observed in eukaryotic flagellar motion, and hydrodynamic models for both were proposed in the past. However, the motility of insect spermatozoa remains largely unexplored. An interesting morphological feature of such cells, first observed in Tenebrio molitor and Bacillus rossius, is the double helical deformation pattern along the flagella, which is characterized by the presence of two superimposed helical flagellar waves (one with a large amplitude and low frequency, and the other with a small amplitude and high frequency). Here we present the first hydrodynamic investigation of the locomotion of insect spermatozoa. The swimming kinematics, trajectories and hydrodynamic efficiency of the swimmer are computed based on the prescribed double helical deformation pattern. We then compare our theoretical predictions with experimental measurements, and explore the dependence of the swimming performance on the geometric and dynamical parameters.

  12. Insect symbionts as hidden players in insect-plant interactions

    NARCIS (Netherlands)

    Frago, E.; Dicke, M.; Godfray, H.C.J.

    2012-01-01

    There is growing evidence of the importance of microbial mutualistic symbioses in insect-plant interactions. Mutualists may affect host plant range and enable insects to manipulate plant physiology for their own benefit. The plant can also be a route for the horizontal transfer of mutualistic microo

  13. Environmental RNAi in herbivorous insects.

    Science.gov (United States)

    Ivashuta, Sergey; Zhang, Yuanji; Wiggins, B Elizabeth; Ramaseshadri, Partha; Segers, Gerrit C; Johnson, Steven; Meyer, Steve E; Kerstetter, Randy A; McNulty, Brian C; Bolognesi, Renata; Heck, Gregory R

    2015-05-01

    Environmental RNAi (eRNAi) is a sequence-specific regulation of endogenous gene expression in a receptive organism by exogenous double-stranded RNA (dsRNA). Although demonstrated under artificial dietary conditions and via transgenic plant presentations in several herbivorous insects, the magnitude and consequence of exogenous dsRNA uptake and the role of eRNAi remains unknown under natural insect living conditions. Our analysis of coleopteran insects sensitive to eRNAi fed on wild-type plants revealed uptake of plant endogenous long dsRNAs, but not small RNAs. Subsequently, the dsRNAs were processed into 21 nt siRNAs by insects and accumulated in high quantities in insect cells. No accumulation of host plant-derived siRNAs was observed in lepidopteran larvae that are recalcitrant to eRNAi. Stability of ingested dsRNA in coleopteran larval gut followed by uptake and transport from the gut to distal tissues appeared to be enabling factors for eRNAi. Although a relatively large number of distinct coleopteran insect-processed plant-derived siRNAs had sequence complementarity to insect transcripts, the vast majority of the siRNAs were present in relatively low abundance, and RNA-seq analysis did not detect a significant effect of plant-derived siRNAs on insect transcriptome. In summary, we observed a broad genome-wide uptake of plant endogenous dsRNA and subsequent processing of ingested dsRNA into 21 nt siRNAs in eRNAi-sensitive insects under natural feeding conditions. In addition to dsRNA stability in gut lumen and uptake, dosage of siRNAs targeting a given insect transcript is likely an important factor in order to achieve measurable eRNAi-based regulation in eRNAi-competent insects that lack an apparent silencing amplification mechanism.

  14. Insect cells for human food

    NARCIS (Netherlands)

    Verkerk, M.C.; Tramper, J.; Trijp, van J.C.M.; Martens, D.E.

    2007-01-01

    There is a need for novel protein sources. Insects are a possible interesting source of protein. They are nutritious in terms of protein (40-75 g/100g dry weight) and minerals. Insect protein is of high quality and has a high digestibility (77-98%) and concentration of essential amino acids (46-96%

  15. Polarization Imaging and Insect Vision

    Science.gov (United States)

    Green, Adam S.; Ohmann, Paul R.; Leininger, Nick E.; Kavanaugh, James A.

    2010-01-01

    For several years we have included discussions about insect vision in the optics units of our introductory physics courses. This topic is a natural extension of demonstrations involving Brewster's reflection and Rayleigh scattering of polarized light because many insects heavily rely on optical polarization for navigation and communication.…

  16. Polarization Imaging and Insect Vision

    Science.gov (United States)

    Green, Adam S.; Ohmann, Paul R.; Leininger, Nick E.; Kavanaugh, James A.

    2010-01-01

    For several years we have included discussions about insect vision in the optics units of our introductory physics courses. This topic is a natural extension of demonstrations involving Brewster's reflection and Rayleigh scattering of polarized light because many insects heavily rely on optical polarization for navigation and communication.…

  17. Eicosanoids mediate insect hemocyte migration

    Science.gov (United States)

    Hemocyte chemotaxis toward infection and wound sites is an essential component of insect defense reactions, although the biochemical signal mechanisms responsible for mediating chemotaxis in insect cells are not well understood. Here we report on the outcomes of experiments designed to test the hyp...

  18. Insect cells for human food

    NARCIS (Netherlands)

    Verkerk, M.C.; Tramper, J.; Trijp, van J.C.M.; Martens, D.E.

    2007-01-01

    There is a need for novel protein sources. Insects are a possible interesting source of protein. They are nutritious in terms of protein (40-75 g/100g dry weight) and minerals. Insect protein is of high quality and has a high digestibility (77-98%) and concentration of essential amino acids (46-96%

  19. Plant Defense against Insect Herbivores

    Science.gov (United States)

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar. Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight, defense compounds. These bioactive specialized plant defense compounds may repel or intoxicate insects, while defense proteins often interfere with their digestion. Volatiles are released upon herbivory to repel herbivores, attract predators or for communication between leaves or plants, and to induce defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects have adapted to resist plant defenses, and in some cases even sequester the compounds and reuse them in their own defense. Both plant defense and insect adaptation involve metabolic costs, so most plant-insect interactions reach a stand-off, where both host and herbivore survive although their development is suboptimal. PMID:23681010

  20. The respiratory proteins of insects.

    Science.gov (United States)

    Burmester, Thorsten; Hankeln, Thomas

    2007-04-01

    For a long time, respiratory proteins have been considered unnecessary in most insects because the tracheal system was thought to be sufficient for oxygen supply. Only a few species that survive under hypoxic conditions were known exceptions. However, recently it has become evident that (1) intracellular hemoglobins belong to the standard repertoire of insects and (2) that hemocyanin is present in many "lower" insects. Intracellular hemoglobins have been identified in Drosophila, Anopheles, Apis and many other insects. In all investigated species, hemoglobin is mainly expressed in the fat body and the tracheal system. The major Drosophila hemoglobin binds oxygen with high affinity. This hemoglobin type possibly functions as a buffer system for oxygen supply at low partial pressures and/or for the protection from an excess of oxygen. Similar hemoglobins, present in much higher concentrations, store oxygen in specialized tracheal organs of the botfly and some backswimmers. The extracellular hemoglobins in the hemolymph of chironomid midges are evolutionary derivatives of the intracellular insect hemoglobins, which emerged in response to the hypoxic environment of the larvae. In addition, several hemoglobin variants of unknown functions have been discovered in insect genomes. Hemocyanins transport oxygen in the hemolymph of stoneflies, but also in the Entognatha and most hemimetabolan taxa. Apparently, hemocyanin has been lost in Holometabola. At present, no physiological or morphological character is known that could explain the presence or loss of hemocyanins in distinct taxa. Nevertheless, the occurrence of respiratory proteins in insects adds further complexity to our view on insect respiration.

  1. Sorghum Insect Problems and Management

    Institute of Scientific and Technical Information of China (English)

    Chunshan Guo; Wei Cui; Xue Feng; Jianzhou Zhao; Guihua Lu

    2011-01-01

    Sorghum (Sorghum bicolor) has high levels of starch, sugar, and fiber and is one of the most important energy crops in the world. Insect damage is one of the challenges that impacts sorghum biomass production. There are at least 150 insect species that can infest sorghum varieties worldwide. These insects can complete several generations within a growing season, they target various parts of sorghum plants at devel- opmental stages, and they cause significant biomass losses. Genetic research has revealed the existence of resistant genetics in sorghum and insect tolerant sorghum varieties have been identified. Various control methods have been developed, yet more effective management is needed for increasing sorghum biomass production. Although there are no transgenic sorghum products on the market yet, biotechnology has been recognized as an important tool for controlling insect pests and increasing sorghum production.

  2. Forest insect pests in Canada

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The papers presented in this book cover the range of forest insect pest management activities in Canada. The first section contains papers on the current status of insect pests by region, including data on insect populations and extent of defoliation caused by the insect. The next section covers pest management technology, including the use of insecticides, insect viruses, fungal pathogens, growth regulators, antifeedants, pheromones, natural predators, and aerial spraying. The third section contains papers on the application of technology and equipment for forest pest control, and includes papers on the impacts of insecticides on the forest environment. The fourth section describes operational control programs by province. The final paper presents future strategies for the management of forest pests. An author index is included.

  3. Plant defense against insect herbivores

    DEFF Research Database (Denmark)

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects......Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar....... Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight...

  4. Plant defense against insect herbivores

    DEFF Research Database (Denmark)

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    have adapted to resist plant defenses, and in some cases even sequester the compounds and reuse them in their own defense. Both plant defense and insect adaptation involve metabolic costs, so most plant-insect interactions reach a stand-off, where both host and herbivore survive although......Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar....... Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight...

  5. Insect Immunity to Entomopathogenic Fungi.

    Science.gov (United States)

    Lu, H-L; St Leger, R J

    2016-01-01

    The study of infection and immunity in insects has achieved considerable prominence with the appreciation that their host defense mechanisms share many fundamental characteristics with the innate immune system of vertebrates. Studies on the highly tractable model organism Drosophila in particular have led to a detailed understanding of conserved innate immunity networks, such as Toll. However, most of these studies have used opportunistic human pathogens and may not have revealed specialized immune strategies that have arisen through evolutionary arms races with natural insect pathogens. Fungi are the commonest natural insect pathogens, and in this review, we focus on studies using Metarhizium and Beauveria spp. that have addressed immune system function and pathogen virulence via behavioral avoidance, the use of physical barriers, and the activation of local and systemic immune responses. In particular, we highlight studies on the evolutionary genetics of insect immunity and discuss insect-pathogen coevolution.

  6. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    Campylobacter in flies Flies of the Muscidae family forage on all kind of faeces – various fly species have different preferences. M domestica prefer pigs, horses and cattle faeces, animals which are all known to frequently excrete Campylobacter. As a result, the insects pick up pathogenic micro...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  7. Quantum Cooperation of Insects

    CERN Document Server

    Summhammer, J

    2005-01-01

    We investigate the cooperation of two insects who share a large number of maximally entangled EPR-pairs to help them decide whether to execute certain actions. In the first example, two ants must push a pebble, which may be too heavy for one ant. In the second example, two distant butterflies must find each other. In both examples the individuals make classical random choices of possible directions, followed by a quantum decision whether to move or to wait. This combination reflects scarce environmental information and the small brain's limited capacity for complex analysis. With quantum mechanical entanglement the two ants can push the pebble up to twice as far as uncorrelated ants, and the two butterflies need only between 48% and 83% of the classical flight path to find each other.

  8. Testing mechanistic models of growth in insects

    OpenAIRE

    Maino, James L.; Kearney, Michael R.

    2015-01-01

    Insects are typified by their small size, large numbers, impressive reproductive output and rapid growth. However, insect growth is not simply rapid; rather, insects follow a qualitatively distinct trajectory to many other animals. Here we present a mechanistic growth model for insects and show that increasing specific assimilation during the growth phase can explain the near-exponential growth trajectory of insects. The presented model is tested against growth data on 50 insects, and compare...

  9. Pinellia ternata agglutinin expression in chloroplasts confers broad spectrum resistance against aphid, whitefly, Lepidopteran insects, bacterial and viral pathogens.

    Science.gov (United States)

    Jin, Shuangxia; Zhang, Xianlong; Daniell, Henry

    2012-04-01

    Broad spectrum protection against different insects and pathogens requires multigene engineering. However, such broad spectrum protection against biotic stress is provided by a single protein in some medicinal plants. Therefore, tobacco chloroplasts were transformed with the agglutinin gene from Pinellia ternata (pta), a widely cultivated Chinese medicinal herb. Pinellia ternata agglutinin (PTA) was expressed up to 9.2% of total soluble protein in mature leaves. Purified PTA showed similar hemagglutination activity as snowdrop lectin. Artificial diet with purified PTA from transplastomic plants showed marked and broad insecticidal activity. In planta bioassays conducted with T0 or T1 generation PTA lines showed that the growth of aphid Myzus persicae (Sulzer) was reduced by 89%-92% when compared with untransformed (UT) plants. Similarly, the larval survival and total population of whitefly (Bemisia tabaci) on transplastomic lines were reduced by 91%-93% when compared with UT plants. This is indeed the first report of lectin controlling whitefly infestation. When transplastomic PTA leaves were fed to corn earworm (Helicoverpa zea), tobacco budworm (Heliothis virescens) or the beet armyworm (spodoptera exigua), 100% mortality was observed against all these three insects. In planta bioassays revealed Erwinia population to be 10,000-fold higher in control than in PTA lines. Similar results were observed with tobacco mosaic virus (TMV) challenge. Therefore, broad spectrum resistance to homopteran (sap-sucking), Lepidopteran insects as well as anti-bacterial or anti-viral activity observed in PTA lines provides a new option to engineer protection against biotic stress by hyper-expression of an unique protein that is naturally present in a medicinal plant.

  10. Evolution of insect P450.

    Science.gov (United States)

    Feyereisen, R

    2006-12-01

    The first fully sequenced insect genomes were those of the fruitfly and the mosquito, both from the order Diptera. Now, with an increasing number and diversity of insect genomes becoming available, the diversity of insect P450 genes can be better appreciated and tentative ideas about the evolution of the CYP (cytochrome P450) superfamily in insects can be proposed. There are four large clades of insect P450 genes that existed before the divergence of the class Insecta and that are also represented by CYP families in vertebrates: the CYP2 clade, the CYP3 clade, the CYP4 clade and the mitochondrial P450 clade. P450s with known or suspected physiological functions are present in each of these clades and only a dozen genes appear to have orthologues or very close paralogues in each insect genome. P450 enzymes from each of these clades have been linked to insecticide resistance or to the metabolism of natural products and xenobiotics. In particular, insects appear to maintain a repertoire of mitochondrial P450 paralogues devoted to the response to environmental challenges.

  11. Social-insect fungus farming

    DEFF Research Database (Denmark)

    Aanen, Duur Kornelis; Boomsma, Jacobus Jan

    2006-01-01

    Which social insects rear their own food? Growing fungi for food has evolved twice in social insects: once in new-world ants about 50 million years ago; and once in old-world termites between 24 and 34 million years ago [1] and [2] . The termites domesticated a single fungal lineage - the extant...... the farming insects with most of their food ( Figure 1 ). No secondary reversals to the ancestral life style are known in either group, which suggests that the transitions to farming were as drastically innovative and irreversible as when humans made this step about 10,000 years ago....

  12. CONTROLE QUÍMICO DO PULGÃO VERDE (Myzus persicae Sulzer, 1776 E DA VAQUINHA (Diabrotica speciosa Germ., 1824 NA CULTURA DO TOMATE RASTEIRO CHEMICAL CONTROL OF THE GREEN PEACH APHID (Myzus persicae, SULZER AND TOMATO LEAF BEETLE (Diabrotica speciosa, GERMAR IN TOMATO PLANTS

    Directory of Open Access Journals (Sweden)

    Danilo Couto

    2007-09-01

    Full Text Available

    O efeito de cinco inseticidas aplicados no tomateiro (Lycopersicum sculentum Mill, visando ao controle do pulgão verde, Myzus persicae SULZER e de vaquinha, Diabrotica speciosa GERM, foi testado em um experimento realizado na área experimental do Departamento de Horticultura da Escota de Agronomia da Universidade Federal de Goiás, no período de maio a setembro de 1994. Os tratamentos foram aplicados via pulverização e constaram de Bulldock 125 SC (dosagem de 100 ml/ 100 1 de água; Bulldock 50 CE (25 e 30 ml/100 l de água; Tamaron BR (100 ml/ 100 l de água; Orthene 750 BR (100 ml/ l00 1 de água e Folidol 600 (100 ml/l00 1 de água; e ainda uma testemunha (sem inseticida. Os resultados obtidos mostraram que todos os tratamentos foram eficientes no controle de M. persicae até sete dias após a aplicação. Aos 14 dias após a aplicação, o Bulldock 50 CE na dosagem de 25 ml/ 100 l de água e o Folidol 600 a 100 ml/ 100 l de água não apresentaram eficiência satisfatória. Com relação à D. speciosa, todos esses produtos foram igualmente eficientes até sete dias após aplicação.

    PALAVRAS-CHAVE: Myzus persicae; diabrotica speciosa; tomateiro; controle químico.

    A trial to control the green peach aphid myzus persicae and tomato leaf beetle Diabrotica speciosa was carried out in Goi

  13. Radar Observation of Insects - Mosquitoes

    Science.gov (United States)

    Frost, E.; Downing, J.

    1979-01-01

    Tests were conducted at several sites over the coastal lowlands of New Jersey and over a region of high plains and low mountains in Oklahoma. In one area, a salt marsh in New Jersey, extensive ground tests were combined with laboratory data on expected insect backscatter to arrive at an extremely convincing model of the insect origin of most Dot Angels. A great deal of insight was studied from radar on the buildup and dispersal of insect swarms, since radar can follow where other means of trapping and observation cannot. Data on large-scale behavior as a function of wind and topography are presented. Displayed techniques which show individual or small swarm motion within some larger cloud or mass, or which can show the overall motion over great distances were developed. The influence of wind and terrain on insect motion and dispersal is determined from radar data.

  14. Eicosanoid actions in insect immunology

    Science.gov (United States)

    In this chapter we review eicosanoid actions in insect immunity. Eicosanoids are oxygenated metabolites of arachidonic acid (AA) and two other C20 polyunsaturated polyunsaturated fatty acids. Groups of eicosanoids include prostaglandins, lipoxygenase products and epoxyeicosatrienoic acids. These ...

  15. Learning and cognition in insects.

    Science.gov (United States)

    Giurfa, Martin

    2015-01-01

    Insects possess small brains but exhibit sophisticated behavioral performances. Recent works have reported the existence of unsuspected cognitive capabilities in various insect species, which go beyond the traditional studied framework of simple associative learning. In this study, I focus on capabilities such as attention, social learning, individual recognition, concept learning, and metacognition, and discuss their presence and mechanistic bases in insects. I analyze whether these behaviors can be explained on the basis of elemental associative learning or, on the contrary, require higher-order explanations. In doing this, I highlight experimental challenges and suggest future directions for investigating the neurobiology of higher-order learning in insects, with the goal of uncovering l architectures underlying cognitive processing.

  16. Insect symbionts in food webs

    Science.gov (United States)

    Henry, Lee M.

    2016-01-01

    Recent research has shown that the bacterial endosymbionts of insects are abundant and diverse, and that they have numerous different effects on their hosts' biology. Here we explore how insect endosymbionts might affect the structure and dynamics of insect communities. Using the obligate and facultative symbionts of aphids as an example, we find that there are multiple ways that symbiont presence might affect food web structure. Many symbionts are now known to help their hosts escape or resist natural enemy attack, and others can allow their hosts to withstand abiotic stress or affect host plant use. In addition to the direct effect of symbionts on aphid phenotypes there may be indirect effects mediated through trophic and non-trophic community interactions. We believe that by using data from barcoding studies to identify bacterial symbionts, this extra, microbial dimension to insect food webs can be better elucidated. This article is part of the themed issue ‘From DNA barcodes to biomes’. PMID:27481779

  17. 46 CFR 108.215 - Insect screens.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Insect screens. 108.215 Section 108.215 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.215 Insect screens. (a) Accommodation spaces must be protected against the admission of insects. (b) Insect screens must be installed when natural ventilation...

  18. How Do Insects Help the Environment?

    Science.gov (United States)

    Hevel, Gary

    2005-01-01

    There are some 5 to 30 million insect species estimated in the world--and the majority of these have yet to be collected or named by science! Of course, the most well known insects are those that cause disease or compete for human agricultural products, but these insects represent only a small fraction of the world's insect population. In reality,…

  19. Clinical Application of Insect Drugs

    Institute of Scientific and Technical Information of China (English)

    钟洪; 赵洁

    2003-01-01

    @@ Chinese insect drugs are drastic in nature, capable ofclearing channels and collaterals to promote a freeflow of qi and blood, and effective in someintractable and obstinate diseases due to long-termstagnation of phlegm and blood, which are hard to betreated by ordinary Chinese drugs. In clinic, properuse of insect drugs can often help raise thetherapeutic effects. Some commonly used pairs ofinsect drugs are introduced in the following.

  20. Social insects inspire human design

    Science.gov (United States)

    Holbrook, C. Tate; Clark, Rebecca M.; Moore, Dani; Overson, Rick P.; Penick, Clint A.; Smith, Adrian A.

    2010-01-01

    The international conference ‘Social Biomimicry: Insect Societies and Human Design’, hosted by Arizona State University, USA, 18–20 February 2010, explored how the collective behaviour and nest architecture of social insects can inspire innovative and effective solutions to human design challenges. It brought together biologists, designers, engineers, computer scientists, architects and businesspeople, with the dual aims of enriching biology and advancing biomimetic design. PMID:20392721

  1. Oviposition pheromones in haematophagous insects.

    Science.gov (United States)

    Seenivasagan, T; Vijayaraghavan, R

    2010-01-01

    Pheromones influencing oviposition behavior in females of haematophagous insects have been the interest of recent past by many group of scientists working on oviposition pheromones. Finding and choosing a good site for oviposition is a challenging task for females of haematophagous insects, especially in those insects which does not have the parental care. Their decisions have far-reaching and profound consequences for the life history of the offspring. In such blood feeding insects, the choice of oviposition site is affected by pheromones, which may function either as deterrents or stimulants in short range, while they may also act as repellents or attractants in long range perception. During the location of a suitable oviposition site for egg laying or a potential host for blood feeding, haematophagous insects mainly use olfactory and visual cues. These pheromones are produced by the ovipositing female or by conspecific larvae co-occurring with gravid females. Adult females detect oviposition pheromones by odor receptors on the antennae, as well as by contact chemoreceptors on tarsi, mouthparts and antennae. Different cues exploited by gravid females from a diversified arena include egg, larva, habitat, microbes, infusions and plant produced volatiles influence the oviposition behavior. Traps baited with pheromones, infusions, and insecticides shall be promising tools for monitoring and control of target insect using integrated vector management strategies. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. Winter prevalence of obligate aphid pathogen Pandora neoaphidis mycosis in the host Myzus persicae populations in southern China: modeling description and biocontrol implication

    Directory of Open Access Journals (Sweden)

    Xiang Zhou

    2012-03-01

    Full Text Available Pandora neoaphidis overwintering had been investigated by monitoring its prevalence in Myzus persicae populations in open fields. Cabbage plants in field plots were weekly taken after mycosis initiation, to count and examine the living and dead aphids infected by P. neoaphidis. Based on the field data, infection levels (I varied with field temperature (T, relative humidity (RH and aphid count (numbers of living aphids per plant, N over days (D, fitting well to the modified logistic equation I=0.91/[1+exp(8.5+(2.0H T H RH-20.2NI0D] (r²=0.897, where H T indicated daily hours of low temperature (90% RH and I0 primary infection level. The model demonstrated the abiotic and biotic factors influencing P. neoaphidis mycosis development in winter, and also verifies the fungal overwintering by infecting available host aphids without a resting stage. Ultimately, P. neoaphidis mycosis reduced 81.4% of aphid populations, presenting great potential for biocontrol.

  3. Predation of the Peach Aphid Myzus persicae by the mirid Predator Macrolophus pygmaeus on Sweet Peppers: Effect of Prey and Predator Density

    Directory of Open Access Journals (Sweden)

    Lara De Backer

    2015-06-01

    Full Text Available Integrated Pest Management strategies are widely implemented in sweet peppers. Aphid biological control on sweet pepers includes curative applications of parasitoids and generalist predators, but with limited efficiency. Macrolophus pygmaeus is a zoophytophagous predator which has been reported to predate on aphids, but has traditionally been used to control other pests, including whiteflies. In this work, we evaluate the effectiveness of M. pygmaeus in controlling Myzus persicae (Homoptera: Aphididae by testing different combinations of aphid and predator densities in cage-experiments under greenhouse conditions. The impact of the presence of an alternative factitious prey (E. kuehniella eggs was also investigated. Macrolophus pygmaeus, at densities of four individuals/plant, caused rapid decline of newly established aphid populations. When aphid infestations were heavy, the mirid bug reduced the aphid numbers but did not fully eradicate aphid populations. The availability of a factitious prey did not influence M. pygmaeus predation on aphids. Based on our data, preventive application of M. pygmaeus, along with a supplementary food source , is recommended to control early infestations of aphids.

  4. Infestation of potato (Solanum tuberosum L.) by the peach-potato aphid (Myzus persicae Sulzer) alters cellular redox status and is influenced by ascorbate.

    Science.gov (United States)

    Kerchev, Pavel I; Fenton, Brian; Foyer, Christine H; Hancock, Robert D

    2012-02-01

    The peach-potato aphid (Myzus persicae Sulzer) is a major pest of potato (Solanum tuberosum L.) but the molecular characterization of this interaction particularly with regard to oxidants and antioxidants remains to be undertaken. Aphid colonies reared on potato leaves containing high ascorbate were twice the size of those grown on leaves with low ascorbate. Infestation-dependent decreases in the abundance of key transcripts such as chloroplastic FeSOD, peroxisomal catalase 2, PR1 and JAZ1 preceded detectable leaf H(2)O(2) or polyphenol accumulation. The leaf glutathione pool was increased 48 h after infestation, but the amount of ascorbate was unchanged. The ascorbate/dehydroacorbate (DHA) ratio was lower at 48 h but the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) was unchanged. While DHA reductase and GSSG reductase activities were unaffected by aphid feeding, non-specific peroxidase activities were enhanced 48 h following aphid infestation. Brown ethanol-insoluble deposits were observed close to leaf veins following aphid infestation. Taken together, the results demonstrate that high ascorbate favours aphid colony expansion and that perturbations in the leaf antioxidant system are intrinsic to the potato leaf response to aphids. Moreover, these changes together with the induction of hormone-related transcripts precede the deposition of defence-associated oxidized polyphenols along the stylet track.

  5. [Rearing of a biotype of Myzus persicae Sulzer on synthetic media. III. Respective nutritive value of L-methionine, L-cysteine and sulfates].

    Science.gov (United States)

    Massonie, G

    1975-01-01

    The respective influence of some different components of a synthetic diet on the survivial and the fecundity of one strain of Myzus persicae Slz. have been established by experiments with the deletion of some components and with variations of their concentrations. 1. L.methionin is the only essential amino-acid amd the variations of its concentrations are related with variations of the fecondity of the aphids. 2. When the amount of L. methionin is inadequate to satisfy the whole sulphur requirements, the supply of L. cystein or inorganic sulphur is beneficial. 3. The nutritional values of L. cystein and of inorganic sulphur seem to be identical. 4. The fecundity of the aphids is depending on the concentration of the everall L. aminoacides and on the amount of L. methionin in the synthetic diet without any interaction between these two factors. So, it can be assumed that the concentration of overall L.amino-acids and the concentration of L. methionin exert separate controls of the fecundity of the aphids.

  6. Interactions between the entomopathogenic fungi Beauveria bassiana (Ascomycota: Hypocreales) and the aphid parasitoid Diaeretiella rapae (Hymenoptera: Braconidae) on Myzus persicae (Hemiptera: Aphididae).

    Science.gov (United States)

    Silva, R J; Alencar, J R D C C; Silva, K P; Cividanes, F J; Duarte, R T; Agostini, L T; Polanczyk, R A

    2014-06-01

    The interactions between the entomopathogenic fungus Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Ascomycota: Hypocreales) and the aphid parasitoid Diaeretiella rapae McIntoch (Hymenoptera: Braconidae) were evaluated under laboratory conditions. Nymphs of Myzus persicae Sulzer (Hemiptera: Aphididae) were first exposed to parasitoid females for 24 h and then 0, 24, and 48 h afterwards sprayed with a solution of B. bassiana. Likewise, aphids were also sprayed with B. bassiana and then exposed to parasitoids at 0, 24, and 48 h afterwards. Parasitism rate varied from 13 to 66.5%, and were significantly lower in treatments where the two agents were exposed within a 0-24 h time interval compared with the control (without B. bassiana). Parasitoid emergence was negatively affected in treatments with B. bassiana spraying and subsequent exposure to D. rapae. Decreases in longevity of adult females of the D. rapae F1 generation were observed in treatments with B. bassiana spraying. The application of these two biological control agents can be used in combination on the control of M. persicae, wherein this use requires effective time management to avoid antagonistic interactions.

  7. Evaluation of the reference genes for expression analysis using quantitative real-time polymerase chain reaction in the green peach aphid, Myzus persicae.

    Science.gov (United States)

    Kang, Zhi-Wei; Liu, Fang-Hua; Tian, Hong-Gang; Zhang, Meng; Guo, Shan-Shan; Liu, Tong-Xian

    2017-04-01

    The green peach aphid, Myzus persicae Sulzer (Hemiptera, Aphididae), is an important cosmopolitan pest. Real time qRT-PCR has been used for target gene expression analysis on M. persicae. Using real time qRT-PCR, the expression levels are normalized on the basis of the reliable reference genes. However, to date, the stability of available reference genes has been insufficient. In this study, we evaluated nine candidate reference genes from M. persicae under diverse experimental conditions. The tested candidate genes were comprehensively ranked based on five alternative methods (RefFinder, geNorm, Normfinder, BestKeeper and the comparative ΔCt method). 18s, Actin and ribosomal protein L27 (L27) were recommended as the most stable reference genes for M. persicae, whereas ribosomal protein L27 (L27) was found to be the least stable reference genes for abiotic studies (photoperiod, temperature and insecticide susceptibility). Our finding not only sheds light on establishing an accurate and reliable normalization of real time qRT-PCR data in M. persicae but also lays a solid foundation for further studies of M. persicae involving RNA interference and functional gene research.

  8. Population growth of Aphis gossypii and Myzus persicae (Hemiptera: Aphididae) in the presence of Linepithema humile and Tapinoma sessile (Hymenoptera: Formicidae).

    Science.gov (United States)

    Powell, Bradford E; Silverman, Jules

    2010-10-01

    Invasive ant species can have dramatic impacts on native ants, through direct predation and by usurping common resources. Most invasive ants and many native ants use honeydew, produced by phloem-sucking hemipterans. Because colonies of invasive ants can become very large after establishment, these ants may facilitate greater hemipteran trophobiont population growth compared with their sympatric native ant counterparts. We examined the population growth of an aphid mutualist, Aphis gossypii, and a nonmutualist, Myzus persicae, exposed to two Dolichoderine ants, Linepithema humile, a globally widespread invasive species, and Tapinoma sessile, a widespread co-occurring native ant, in North America in an enemy-free laboratory study. L. humile worker foraging activity was at least twice that of T. sessile, and populations of the myrmecophile, A. gossypii, were greater when exposed to L. humile than T. sessile, possibly caused, in part, by more frequent encounters with L. humile. L. humile ignored M. persicae when A. gossypii was absent, whereas T. sessile preyed on it. Both ant species preyed on M. persicae when A. gossypii was also present. This suggested that both ants may assess nutritional gains from aphid species (i.e., honeydew versus body tissue), eliminating less productive aphids competing for host plant space. Through their impact on populations of hemipteran mutualists, we suggest that colonies of L. humile and perhaps other invasive ants may acquire more honeydew than native ants, thereby fueling colony growth that leads to numerical dominance and widespread success in introduced environments.

  9. SELECTION OF BEAUVERIA BASSIANA (BALSAMO VUILLEMIN ISOLATES FOR MANAGEMENT OF MYZUS PERSICAE (SULTZAR (HOM.: APHIDAE BASED ON VIRULENCE AND GROWTH RELATED CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Mohammad S. Al-alawi

    2014-01-01

    Full Text Available Isolates of the entomopathogenic fungus Beauveria bassiana originated from Jordan were evaluated for their efficacy against the green peach aphid, Myzus persicae under laboratory and greenhouse conditions. Efficacy evaluation involved testing all isolates at a concentration of 1×107 conidia/mL followed by concentration dependent and greenhouse bioassays for the top virulent isolates. Growth characteristics related to virulence were evaluated for high, intermediate and low virulent isolates. Results showed that three isolates namely: BAU004, BAU018 and BAU019 were highly virulent to the aphid in the laboratory causing more than 75% infection. In the greenhouse, the three isolates caused infection from 41.3 to 46.5%. For the growth characteristics, isolate BAU019 produced more spores than the other highly virulent ones including the commercial isolate GHA. Highly virulent isolates also showed faster hyphal growth than low virulent isolates. These findings indicate that isolates BAU004, Bau018 and BAU019 might be developed as commercial microbial insecticides for safe and effective control of green peach aphid.

  10. Examination of the biological effects of high anionic peroxidase production in tobacco plants grown under field conditions. I. Insect pest damage.

    Science.gov (United States)

    Dowd, Patrick F; Lagrimini, L Mark

    2006-04-01

    At least 25 wild type and high peroxidase tobacco Nicotiana tabacum L. plants were examined semiweekly over several weeks for pest insect distribution and damage in a 2 year field study. Incidence and/or severity of naturally occurring caterpillar damage (dingy cutworm (Feltia ducens Walker), black cutworm (Agrotis ipsilon (Hufnagel), tobacco hornworm (Manduca sexta L.), and false tobacco budworm (= corn earworm Helicoverpa zea (Boddie)) was significantly reduced at several sample dates for high peroxidase vs. wild type plants. These results parallel those of prior laboratory studies with caterpillars. The number of adult whiteflies (Trialeurodes vaporariorum (Westwood) per plant was significantly reduced on high peroxidase compared to wild type plants on most sample dates in both years. The number of plants with leaves containing >100 aphids (primarily Myzus persicae Sulzer) per leaf on high peroxidase plants was significantly lower that on wild type plants after an equivalent invasion period in both years. A significantly higher proportion of aphids were found dead on leaf five of high peroxidase compared to wild type plants at most sample dates in both years. These results indicate that high peroxidase plants have resistance to a wide range of insects, implicating this enzyme as a broad range resistance mechanism.

  11. Study on the Diseases and Insect Pests of Peach Tree in the Greenhouse%大棚温室桃树病虫害研究

    Institute of Scientific and Technical Information of China (English)

    李国英

    2015-01-01

    The kinds and characteristics of diseases and insect pests on the peach tree cultivated in the greenhouse are different from that in the orchard .Through the investigation of diseases and insect pests on the peach tree in the green‐house ,the author found out the kinds and occurrence characteristics of main diseases and insect pests and provided evi‐dence for control .Survey results showed that the main diseases and insect pests of peach tree in the greenhouse is 20 spe‐cies which included 6 kinds of diseases and 14 kinds of insect pests;The main diseases and insect pests must be controlled including 8 kinds ,which were peach bacterial shot hole ,peach gummosis ,peach crown gall ,Myzus persicae ,Hyaloptera amygdale ,Tetyanyhus viennensis ,Lyonetia clerkella ,Empoasca flavescens .Through observing occurrence regularity of the main diseases and insect pests ,the author summed up the characteristics of occurrence of the main diseases and insect pests of peach tree in the greenhouse .%大棚内栽培桃树与露地果园生长的桃树病虫害种类与发生特点有所不同,通过对大棚栽培桃树病虫害调查,查明主要病虫害的种类与发生特点,为防治工作提供依据。结果表明,大棚桃树主要病虫害种类共有20种,其中病害6种,虫害14种,主要的必须进行防治的病虫害有桃细菌性穿孔病、桃流胶病、桃根癌病、桃蚜、桃粉大尾蚜、山楂红蜘蛛、桃潜蛾、小绿叶蝉8种。通过对主要病虫害的发生危害规律的观察,总结出发生特点。

  12. Can insects develop resistance to insect pathogenic fungi?

    Directory of Open Access Journals (Sweden)

    Ivan M Dubovskiy

    Full Text Available Microevolutionary adaptations and mechanisms of fungal pathogen resistance were explored in a melanic population of the Greater wax moth, Galleria mellonella. Under constant selective pressure from the insect pathogenic fungus Beauveria bassiana, 25(th generation larvae exhibited significantly enhanced resistance, which was specific to this pathogen and not to another insect pathogenic fungus, Metarhizium anisopliae. Defense and stress management strategies of selected (resistant and non-selected (susceptible insect lines were compared to uncover mechanisms underpinning resistance, and the possible cost of those survival strategies. We hypothesize that the insects developed a transgenerationally primed resistance to the fungus B. bassiana, a costly trait that was achieved not by compromising life-history traits but rather by prioritizing and re-allocating pathogen-species-specific augmentations to integumental front-line defenses that are most likely to be encountered by invading fungi. Specifically during B. bassiana infection, systemic immune defenses are suppressed in favour of a more limited but targeted repertoire of enhanced responses in the cuticle and epidermis of the integument (e.g. expression of the fungal enzyme inhibitor IMPI, and cuticular phenoloxidase activity. A range of putative stress-management factors (e.g. antioxidants is also activated during the specific response of selected insects to B. bassiana but not M. anisopliae. This too occurs primarily in the integument, and probably contributes to antifungal defense and/or helps ameliorate the damage inflicted by the fungus or the host's own immune responses.

  13. Can insects develop resistance to insect pathogenic fungi?

    Science.gov (United States)

    Dubovskiy, Ivan M; Whitten, Miranda M A; Yaroslavtseva, Olga N; Greig, Carolyn; Kryukov, Vadim Y; Grizanova, Ekaterina V; Mukherjee, Krishnendu; Vilcinskas, Andreas; Glupov, Viktor V; Butt, Tariq M

    2013-01-01

    Microevolutionary adaptations and mechanisms of fungal pathogen resistance were explored in a melanic population of the Greater wax moth, Galleria mellonella. Under constant selective pressure from the insect pathogenic fungus Beauveria bassiana, 25(th) generation larvae exhibited significantly enhanced resistance, which was specific to this pathogen and not to another insect pathogenic fungus, Metarhizium anisopliae. Defense and stress management strategies of selected (resistant) and non-selected (susceptible) insect lines were compared to uncover mechanisms underpinning resistance, and the possible cost of those survival strategies. We hypothesize that the insects developed a transgenerationally primed resistance to the fungus B. bassiana, a costly trait that was achieved not by compromising life-history traits but rather by prioritizing and re-allocating pathogen-species-specific augmentations to integumental front-line defenses that are most likely to be encountered by invading fungi. Specifically during B. bassiana infection, systemic immune defenses are suppressed in favour of a more limited but targeted repertoire of enhanced responses in the cuticle and epidermis of the integument (e.g. expression of the fungal enzyme inhibitor IMPI, and cuticular phenoloxidase activity). A range of putative stress-management factors (e.g. antioxidants) is also activated during the specific response of selected insects to B. bassiana but not M. anisopliae. This too occurs primarily in the integument, and probably contributes to antifungal defense and/or helps ameliorate the damage inflicted by the fungus or the host's own immune responses.

  14. Evolutionary plasticity of insect immunity.

    Science.gov (United States)

    Vilcinskas, Andreas

    2013-02-01

    Many insect genomes have been sequenced and the innate immune responses of several species have been studied by transcriptomics, inviting the comparative analysis of immunity-related genes. Such studies have demonstrated significant evolutionary plasticity, with the emergence of novel proteins and protein domains correlated with insects adapting to both abiotic and biotic environmental stresses. This review article focuses on effector molecules such as antimicrobial peptides (AMPs) and proteinase inhibitors, which display greater evolutionary dynamism than conserved components such as immunity-related signaling molecules. There is increasing evidence to support an extended role for insect AMPs beyond defense against pathogens, including the management of beneficial endosymbionts. The total number of AMPs varies among insects with completed genome sequences, providing intriguing examples of immunity gene expansion and loss. This plasticity is discussed in the context of recent developments in evolutionary ecology suggesting that the maintenance and deployment of immune responses reallocates resources from other fitness-related traits thus requiring fitness trade-offs. Based on our recent studies using both model and non-model insects, I propose that insect immunity genes can be lost when alternative defense strategies with a lower fitness penalty have evolved, such as the so-called social immunity in bees, the chemical sanitation of the microenvironment by some beetles, and the release of antimicrobial secondary metabolites in the hemolymph. Conversely, recent studies provide evidence for the expansion and functional diversification of insect AMPs and proteinase inhibitors to reflect coevolution with a changing pathosphere and/or adaptations to habitats or food associated with microbial contamination. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Insect Cell Culture and Biotechnology

    Institute of Scientific and Technical Information of China (English)

    Robert R.Granados; Guoxun Li; G.W.Blissard

    2007-01-01

    The continued development of new cell culture technology is essential for the future growth and application of insect cell and baculovirus biotechnology. The use of cell lines for academic research and for commercial applications is currently dominated by two cell lines; the Spodoptera frugiperda line, SF21 (and its clonal isolate, SF9), and the Trichoplusia ni line, BTI 5B1-4, commercially known as High Five cells. The long perceived prediction that the immense potential application of the baculovirus-insect cell system, as a tool in cell and molecular biology, agriculture, and animal health, has been achieved. The versatility and recent applications of this popular expression system has been demonstrated by both academia and industry and it is clear that this cell-based system has been widely accepted for biotechnological applications. Numerous small to midsize startup biotechnology companies in North America and the Europe are currently using the baculovirus-insect cell technology to produce custom recombinant proteins for research and commercial applications. The recent breakthroughs using the baculovirus-insect cell-based system for the development of several commercial products that will impact animal and human health will further enhance interest in this technology by pharma. Clearly, future progress in novel cell and engineering advances will lead to fundamental scientific discoveries and serve to enhance the utility and applications of this baculovirus-insect cell system.

  16. Drosophila's view on insect vision.

    Science.gov (United States)

    Borst, Alexander

    2009-01-13

    Within the last 400 million years, insects have radiated into at least a million species, accounting for more than half of all known living organisms: they are the most successful group in the animal kingdom, found in almost all environments of the planet, ranging in body size from a mere 0.1 mm up to half a meter. Their eyes, together with the respective parts of the nervous system dedicated to the processing of visual information, have long been the subject of intense investigation but, with the exception of some very basic reflexes, it is still not possible to link an insect's visual input to its behavioral output. Fortunately for the field, the fruit fly Drosophila is an insect, too. This genetic workhorse holds great promise for the insect vision field, offering the possibility of recording, suppressing or stimulating any single neuron in its nervous system. Here, I shall give a brief synopsis of what we currently know about insect vision, describe the genetic toolset available in Drosophila and give some recent examples of how the application of these tools have furthered our understanding of color and motion vision in Drosophila.

  17. Characterization of acetylcholinesterases, and their genes, from the hemipteran species Myzus persicae (Sulzer), Aphis gossypii (Glover), Bemisia tabaci (Gennadius) and Trialeurodes vaporariorum (Westwood).

    Science.gov (United States)

    Javed, N; Viner, R; Williamson, M S; Field, L M; Devonshire, A L; Moores, G D

    2003-12-01

    Gene sequences encoding putative acetylcholinesterases have been reported for four hemipteran insect species. Although acetylcholinesterase insensitivity occurs in insecticide-resistant populations of each of these species, no mutations were detected in the gene sequences from the resistant insects. This, coupled with a series of experiments using novel reversible inhibitors to compare the biochemical characteristics of acetylcholinesterase from a range of insect species, showed that the cloned cDNA fragments are unlikely to encode the hemipteran synaptic acetylcholinesterases, and there is likely to be a second ace locus.

  18. NUMERICAL SIMULATION OF INSECT FLIGHT

    Institute of Scientific and Technical Information of China (English)

    CHENG Mu-lin; MIAO Wen-bo; ZHONG Chang-sheng

    2006-01-01

    In the non-inertial coordinates attached to the model wing, the two-dimensional unsteady flow field triggered by the motion of the model wing, similar to the flapping of the insect wings, was numerically simulated. One of the advantages of our method is that it has avoided the difficulty related to the moving-boundary problem. Another advantage is that the model has three degrees of freedom and can be used to simulate arbitrary motions of a two-dimensional wing in plane only if the motion is known. Such flexibility allows us to study how insects control their flying. Our results show that there are two parameters that are possibly utilized by insects to control their flight: the phase difference between the wing translation and rotation, and the lateral amplitude of flapping along the direction perpendicular to the average flapping plane.

  19. Neurosecretion: peptidergic systems in insects

    Science.gov (United States)

    Predel, R.; Eckert, Manfred

    Insect neuropeptides are produced in less than 1% of the cells of the central nervous system. Despite this, they are important messenger molecules which influence nearly all physiological processes, including behaviour. They can act as transmitters, modulators and classical hormones, and often exhibit pleiotropic functions when released into the haemolymph. The large number of neuropeptides that has been identified from some of the model organisms among insects underlines the complexity of the neurosecretory system; studies about the coordinated actions of these substances are in their preliminary stages. Recent advances in insect neuropeptide research will be reviewed here, concentrating on the distribution of multiple peptide forms in the central nervous system and adjacent neurohaemal organs, and the role of neuropeptides in eclosion behaviour.

  20. Insects, infestations and nutrient fluxes

    Science.gov (United States)

    Michalzik, B.

    2012-04-01

    Forest ecosystems are characterized by a high temporal and spatial variability in the vertical transfer of energy and matter within the canopy and the soil compartment. The mechanisms and controlling factors behind canopy processes and system-internal transfer dynamics are imperfectly understood at the moment. Seasonal flux diversities and inhomogeneities in throughfall composition have been reported from coniferous and deciduous forests, and in most cases leaf leaching has been considered as principle driver for differences in the amount and quality of nutrients and organic compounds (Tukey and Morgan 1963). Since herbivorous insects and the processes they initiate received less attention in past times, ecologists now emphasize the need for linking biological processes occurring in different ecosystem strata to explain rates and variability of nutrient cycling (Bardgett et al. 1998, Wardle et al. 2004). Consequently, herbivore insects in the canopies of forests are increasingly identified to play an important role for the (re)cycling and availability of nutrients, or, more generally, for the functioning of ecosystems not only in outbreak situations but also at endemic (non-outbreak) density levels (Stadler et al. 2001, Hunter et al. 2003). Before, little attention was paid to insect herbivores when quantifying element and energy fluxes through ecosystems, although the numerous and different functions insects fulfill in ecosystems (e.g. as pollinators, herbivores or detritivores) were unanimously recognized (Schowalter 2000). Amongst the reasons for this restraint was the argument that the total biomass of insects tends to be relatively low compared to the biomass of trees or the pool of soil organic matter (Ohmart et al. 1983). A second argument which was put forward to justify the inferior role of insects in nutrient cycling were the supposed low defoliation losses between 5-10% of the annual leaf biomass, or net primary production, due to insect herbivory under

  1. Biogenic Amines in Insect Antennae

    Directory of Open Access Journals (Sweden)

    Marianna I. Zhukovskaya

    2017-06-01

    Full Text Available Insect antenna is a multisensory organ, each modality of which can be modulated by biogenic amines. Octopamine (OA and its metabolic precursor tyramine (TA affect activity of antennal olfactory receptor neurons. There is some evidence that dopamine (DA modulates gustatory neurons. Serotonin can serve as a neurotransmitter in some afferent mechanosensory neurons and both as a neurotransmitter and neurohormone in efferent fibers targeted at the antennal vessel and mechanosensory organs. As a neurohormone, serotonin affects the generation of the transepithelial potential by sensillar accessory cells. Other possible targets of biogenic amines in insect antennae are hygro- and thermosensory neurons and epithelial cells. We suggest that the insect antenna is partially autonomous in the sense that biologically active substances entering its hemolymph may exert their effects and be cleared from this compartment without affecting other body parts.

  2. Calcitonin-like diuretic hormones in insects.

    Science.gov (United States)

    Zandawala, Meet

    2012-10-01

    Insect neuropeptides control various biological processes including growth, development, homeostasis and reproduction. The calcitonin-like diuretic hormone (CT/DH) is one such neuropeptide that has been shown to affect salt and water transport by Malpighian tubules of several insects. With an increase in the number of sequenced insect genomes, CT/DHs have been predicted in several insect species, making it easier to characterize the gene encoding this hormone and determine its function in the species in question. This mini review summarizes the current knowledge on insect CT/DHs, focusing on mRNA and peptide structures, distribution patterns, physiological roles, and receptors in insects.

  3. Uso potencial de aceites esenciales de Cymbopogon citratus y Laurus nobilis para el control de Myzus persicae en lechuga bajo cubierta

    OpenAIRE

    Valdés, Ramiro Julián

    2017-01-01

    El pulgón verde del duraznero, Myzus persicae (Sulzer), es un àfido polífago considerado una de las plagas de mayor dificultad de manejo en los cultivos hortícolas bajo cubierta. Su control se realiza con plaguicidas sintéticos convencionales. El uso de estos productos genera problemas de residuos tóxicos, inconvenientes en los aplicadores y resistencia de los insectos a los mismos. Los aceites esenciales constituyen productos naturales ensayados para el control de plagas, siendo una estrateg...

  4. Insects as a Nitrogen Source for Plants.

    Science.gov (United States)

    Behie, Scott W; Bidochka, Michael J

    2013-07-31

    Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively) are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF) provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates.

  5. Insects as a Nitrogen Source for Plants

    Directory of Open Access Journals (Sweden)

    Michael J. Bidochka

    2013-07-01

    Full Text Available Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates.

  6. Edible insects in China: Utilization and prospects.

    Science.gov (United States)

    Feng, Ying; Chen, Xiao-Ming; Zhao, Min; He, Zhao; Sun, Long; Wang, Cheng-Ye; Ding, Wei-Feng

    2017-02-22

    The use of edible insects has a long history in China, where they have been consumed for more than 2000 years. In general, the level of acceptance is high for the consumption of insects in China. Many studies on edible insects have been conducted in the last 20 years, and the scope of the research includes the culture of entomophagy and the identification, nutritional value, farming and breeding of edible insects, in addition to food production and safety. Currently, 324 species of insects from 11 orders are documented that are either edible or associated with entomophagy in China, which include the common edible species, some less commonly consumed species and some medicinal insects. However, only approximately 10 to 20 types of insects are regularly consumed. The nutritional values for 174 species are available in China, including edible, feed and medicinal species. Although the nutritional values vary among species, all the insects examined contain protein, fat, vitamins and minerals at levels that meet human nutritional requirements. Edible insects were, and continue to be, consumed by different ethnic groups in many parts of China. People directly consume insects or food products made from insects. The processing of products from insect protein powder, oil and chitin, and the development of healthcare foods has been studied in China. People also consume insects indirectly by eating livestock that were fed insects, which may be a more acceptable pathway to use insects in human diets. Although limited, the data on the food safety of insects indicate that insects are safe for food or feed. Incidences of allergic reactions after consuming silkworm pupae, cicadas and crickets have been reported in China. Insect farming is a unique breeding industry in rural China and is a source of income for local people. Insects are reared and bred for human food, medicine and animal feed using two approaches in China: the insects are either fully domesticated and reared

  7. Differences in the Detoxification Metabolism between Two clonal Lineages of the Aphid Myzus persicae (Sulzer (Hemiptera: Aphididae Reared on Tobacco (Nicotiana tabacum L. Diferencias en el Metabolismo de Detoxificación entre dos Linajes Clonales del Áfido Myzus persicae (Sulzer (Hemiptera: Aphididae creados sobre tabaco (Nicotiana tabacum L.

    Directory of Open Access Journals (Sweden)

    Marco A Cabrera-Brandt

    2010-12-01

    Full Text Available Myzus persicae (Sulzer is a highly polyphagous aphid species, with a subspecies (M. persicae nicotianae well adapted to tobacco (Nicotiana tabacum L.. We evaluated the effect of this host plant on the aphid performance and detoxification enzymes, in order to test the participation of xenobiotic metabolism on the ability of this aphid to overcome the tobacco chemical defences. Two genotypes, one corresponding to the only M. persicae nicotianae genotype reported in Chile on tobacco, and one genotype belonging to M. persicae sensu stricto were reared on tobacco and pepper (Capsicum annuum L., respectively. M. persicae nicotianae showed a significantly higher intrinsic rate of increase (r m on pepper than on tobacco, and M. persicae s.s. performed similarly, but with no reproduction at all on tobacco. In order to evaluate the effect of tobacco on detoxification enzymes, esterases, glutathione S-transferases (GST and cytochrome P-450 monooxygenases (MO were determined in both selected aphid genotypes after 12, 24, 36, 48 and 72 h of rearing on tobacco and pepper. M. persicae nicotianae exhibited the higher total esterase activities when reared on tobacco than on pepper after 48 h of rearing, while the activities of GST and MO did not show any significant difference between host-plants and duration of treatment. For M. persicae s.s., no significant differences were observed among host-plants for the studied enzymes. These results suggest a participation of the esterases, on the ability of this M. persicae nicotianae to overcome the tobacco defences.Myzus persicae (Sulzer es un áfido polífago que incluye a Myzus persicae nicotianae, una subespecie altamente adaptada sobre tabaco (Nicotiana tabacum L.. Evaluamos el efecto del tabaco sobre el desempeño biológico y sobre determinadas enzimas de detoxificación en áfidos, para estudiar su participación en la capacidad de M. persicae nicotianae de superar las defensas químicas del tabaco. Dos

  8. Aphicidal Activity of Illicium verum Fruit Extracts and Their Effects on the Acetylcholinesterase and Glutathione S-transferases Activities in Myzus persicae (Hemiptera: Aphididae).

    Science.gov (United States)

    Zhou, Ben-Guo; Wang, Sa; Dou, Ting-Ting; Liu, Su; Li, Mao-Ye; Hua, Ri-Mao; Li, Shi-Guang; Lin, Hua-Feng

    2016-01-01

    This study aims to explore the aphicidal activity and underlying mechanism of Illicium verum Hook. f. that is used as both food and medicine. The contact toxicity of the extracts from I. verum fruit with methyl alcohol (MA), ethyl acetate (EA), and petroleum ether (PE) against Myzus persicae (Sulzer), and the activities of acetylcholinesterase (AChE) and glutathione S-transferases (GSTs) of M. persicae after contact treatment were tested. The results showed that MA, EA, and PE extracts of 1.000 mg/l caused, respectively, M. persicae mortalities of 68.93%, 89.95% and 74.46%, and the LC50 of MA, EA, and PE extracts were 0.31, 0.14 and 0.27 mg/l at 72 h after treatment, respectively; the activities of AChE and GSTs in M. persicae were obviously inhibited by the three extracts, as compared with the control, with strong dose and time-dependent effects, the inhibition rates on the whole reached more than 50.00% at the concentration of 1.000 mg/l at 72 h after treatment. The inhibition of the extracts on AChE and GSTs activities (EA extract > PE extract > MA extract) were correlated with theirs contact toxic effects, so it is inferred that the decline of the metabolic enzymes activities may be one of important reasons of M. persicae death. The study results suggested that I. verum extracts have potential as a eco-friendly biopesticide in integrated pest management against M. persicae.

  9. The resistant mechanism of Myzus persicae to pesticide in Yunnan Province%云南烟蚜抗药性机制研究

    Institute of Scientific and Technical Information of China (English)

    宋春满; 邓建华

    2012-01-01

    通过比较云南烟蚜敏感品系和抗性品系的解毒酶(α-乙酸萘酯羧酸酯酶、β-乙酸萘酯羧酸酯酶)和靶标酶(乙酰胆碱酯酶)的活力,研究了烟蚜对有机磷、拟除虫菊酯和氨基甲酸酯类杀虫剂抗性的生化机制,并通过酯酶基因扩增检测和钠离子通道突变检测,研究了其抗性的分子机制.结果表明:α-乙酸萘酯羧酸酯酶活力增强是烟蚜对有机磷类、氨基甲酸酯类杀虫剂及拟除虫菊酯类杀虫剂的抗性机制之一;乙酰胆碱酯酶在烟蚜对有机磷杀虫剂抗性中起重要作用;3个抗性品系烟蚜均没有发生酯酶基因扩增,抗拟除虫菊酯品系烟蚜发生了钠离子通道突变.%To study the biochemical and molecular mechanism of resistance to organophosphorus, pyre- throid and carbarmate pesticide, the activity of the detoxicating enzymes (α - NA carboxylesterase, β — NA carboxylesterase) and the target enzyme ( acetylcholinesterase) were compared among the susceptible and the resistant strain of Myzus persicae. The results showed that enhanced α - NA carboxylesterase played an important role in the resistance to the three kinds of pesticides, so did the acetylcholinesterase to organophosphorus pesticide. All the three resistant strains had no amplified esterase genes, and the strain resistant to pyrethroid had a mutation in sodium channel.

  10. Metabolite Profiling Reveals a Specific Response in Tomato to Predaceous Chrysoperla carnea Larvae and Herbivore(s)-Predator Interactions with the Generalist Pests Tetranychus urticae and Myzus persicae.

    Science.gov (United States)

    Errard, Audrey; Ulrichs, Christian; Kühne, Stefan; Mewis, Inga; Mishig, Narantuya; Maul, Ronald; Drungowski, Mario; Parolin, Pia; Schreiner, Monika; Baldermann, Susanne

    2016-01-01

    The spider mite Tetranychus urticae Koch and the aphid Myzus persicae (Sulzer) both infest a number of economically significant crops, including tomato (Solanum lycopersicum). Although used for decades to control pests, the impact of green lacewing larvae Chrysoperla carnea (Stephens) on plant biochemistry was not investigated. Here, we used profiling methods and targeted analyses to explore the impact of the predator and herbivore(s)-predator interactions on tomato biochemistry. Each pest and pest-predator combination induced a characteristic metabolite signature in the leaf and the fruit thus, the plant exhibited a systemic response. The treatments had a stronger impact on non-volatile metabolites including abscisic acid and amino acids in the leaves in comparison with the fruits. In contrast, the various biotic factors had a greater impact on the carotenoids in the fruits. We identified volatiles such as myrcene and α-terpinene which were induced by pest-predator interactions but not by single species, and we demonstrated the involvement of the phytohormone abscisic acid in tritrophic interactions for the first time. More importantly, C. carnea larvae alone impacted the plant metabolome, but the predator did not appear to elicit particular defense pathways on its own. Since the presence of both C. carnea larvae and pest individuals elicited volatiles which were shown to contribute to plant defense, C. carnea larvae could therefore contribute to the reduction of pest infestation, not only by its preying activity, but also by priming responses to generalist herbivores such as T. urticae and M. persicae. On the other hand, the use of C. carnea larvae alone did not impact carotenoids thus, was not prejudicial to the fruit quality. The present piece of research highlights the specific impact of predator and tritrophic interactions with green lacewing larvae, spider mites, and aphids on different components of the tomato primary and secondary metabolism for the first

  11. Metabolite profiling reveals a specific response in tomato to predaceous Chrysoperla carnea larvae and herbivore(s-predator interactions with the generalist pests Tetranychus urticae and Myzus persicae

    Directory of Open Access Journals (Sweden)

    Audrey Errard

    2016-08-01

    Full Text Available The spider mite Tetranychus urticae Koch and the aphid Myzus persicae (Sulzer both infest a number of economically significant crops, including tomato (Solanum lycopersicum. Although used for decades to control pests, the impact of green lacewing larvae Chrysoperla carnea (Stephens on plant biochemistry was not investigated. Here we used profiling methods and targeted analyses to explore the impact of the predator and herbivore(s-predator interactions on tomato biochemistry. Each pest and pest-predator combination induced a characteristic metabolite signature in the leaf and the fruit thus, the plant exhibited a systemic response. The treatments had a stronger impact on non-volatile metabolites including abscisic acid and amino acids in the leaves in comparison with the fruits. In contrast, the various biotic factors had a greater impact on the carotenoids in the fruits. We identified volatiles such as myrcene and α-terpinene which were induced by pest-predator interactions but not by single species, and we demonstrated the involvement of the phytohormone abscisic acid in tritrophic interactions for the first time. More importantly, C. carnea larvae alone impacted the plant metabolome, but the predator did not appear to elicit particular defense pathways on its own. Since the presence of both C. carnea larvae and pest individuals elicited volatiles which were shown to contribute to plant defense, C. carnea larvae could therefore contribute to the reduction of pest infestation, not only by its preying activity, but also by priming responses to generalist herbivores such as T. urticae and M. persicae. On the other hand, the use of C. carnea larvae alone did not impact carotenoids thus, was not prejudicial to the fruit quality. The present piece of research highlights the specific impact of predator and tritrophic interactions with green lacewing larvae, spider mites and aphids on different components of the tomato primary and secondary metabolism

  12. Trapping of insects in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Pathak, S.C.; Parulekar, A.H.

    Some insects caught on RV Gaveshani, while on a cruise in the Arabian Sea in May-June 1986 is reported Of the 23 insects caught, 16 were lepidopterans An interesting flight behaviour of Psychota sp is described...

  13. The Curious Connection Between Insects and Dreams.

    Science.gov (United States)

    Klein, Barrett A

    2011-12-21

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans' dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream's significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives.

  14. FAQ: Insect Repellent Use and Safety

    Science.gov (United States)

    ... Mosquito Surveillance Software Health Education Public Service Videos Insect Repellent Use & Safety Recommend on Facebook Tweet Share ... the repellent with you. Top of Page Can insect repellents be used on children? Yes. Most products ...

  15. Insect response to plant defensive protease inhibitors.

    Science.gov (United States)

    Zhu-Salzman, Keyan; Zeng, Rensen

    2015-01-07

    Plant protease inhibitors (PIs) are natural plant defense proteins that inhibit proteases of invading insect herbivores. However, their anti-insect efficacy is determined not only by their potency toward a vulnerable insect system but also by the response of the insect to such a challenge. Through the long history of coevolution with their host plants, insects have developed sophisticated mechanisms to circumvent antinutritional effects of dietary challenges. Their response takes the form of changes in gene expression and the protein repertoire in cells lining the alimentary tract, the first line of defense. Research in insect digestive proteases has revealed the crucial roles they play in insect adaptation to plant PIs and has brought about a new appreciation of how phytophagous insects employ this group of molecules in both protein digestion and counterdefense. This review provides researchers in related fields an up-to-date summary of recent advances.

  16. The Curious Connection Between Insects and Dreams

    Directory of Open Access Journals (Sweden)

    Barrett A. Klein

    2011-12-01

    Full Text Available A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives.

  17. The Curious Connection Between Insects and Dreams

    Science.gov (United States)

    Klein, Barrett A.

    2011-01-01

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives. PMID:26467945

  18. Insect Evolution: The Origin of Wings.

    Science.gov (United States)

    Ross, Andrew

    2017-02-06

    The debate on the evolution of wings in insects has reached a new level. The study of primitive fossil insect nymphs has revealed that wings developed from a combination of the dorsal part of the thorax and the body wall.

  19. Making Connections with Insect Royalty.

    Science.gov (United States)

    Hobbie, Ann

    2000-01-01

    Describes a one-month sixth grade class activity with monarch butterflies called Monarch in the Classroom. Students learn about insects, especially the class material butterflies, including their life cycle, eating habits, migration, and how they overwinter. The lesson plan covers sorting animals, focusing on features, analyzing the community for…

  20. Anaphylaxis to Insect Venom Allergens

    DEFF Research Database (Denmark)

    Ollert, Markus; Blank, Simon

    2015-01-01

    Anaphylaxis due to Hymenoptera stings is one of the most severe consequences of IgE-mediated hypersensitivity reactions. Although allergic reactions to Hymenoptera stings are often considered as a general model for the underlying principles of allergic disease, diagnostic tests are still hampered......, and to contribute to the understanding of the immunological mechanisms elicited by insect venoms....

  1. Edible insects are the future?

    NARCIS (Netherlands)

    Huis, van Arnold

    2016-01-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of

  2. Developmental constraint of insect audition

    Directory of Open Access Journals (Sweden)

    Strauß Johannes

    2006-12-01

    Full Text Available Abstract Background Insect ears contain very different numbers of sensory cells, from only one sensory cell in some moths to thousands of sensory cells, e.g. in cicadas. These differences still await functional explanation and especially the large numbers in cicadas remain puzzling. Insects of the different orders have distinct developmental sequences for the generation of auditory organs. These sensory cells might have different functions depending on the developmental stages. Here we propose that constraints arising during development are also important for the design of insect ears and might influence cell numbers of the adults. Presentation of the hypothesis We propose that the functional requirements of the subadult stages determine the adult complement of sensory units in the auditory system of cicadas. The hypothetical larval sensory organ should function as a vibration receiver, representing a functional caenogenesis. Testing the hypothesis Experiments at different levels have to be designed to test the hypothesis. Firstly, the neuroanatomy of the larval sense organ should be analyzed to detail. Secondly, the function should be unraveled neurophysiologically and behaviorally. Thirdly, the persistence of the sensory cells and the rebuilding of the sensory organ to the adult should be investigated. Implications of the hypothesis Usually, the evolution of insect ears is viewed with respect to physiological and neuronal mechanisms of sound perception. This view should be extended to the development of sense organs. Functional requirements during postembryonic development may act as constraints for the evolution of adult organs, as exemplified with the auditory system of cicadas.

  3. Edible insects are the future?

    NARCIS (Netherlands)

    Huis, van Arnold

    2016-01-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of

  4. Allergic reactions to insect secretions.

    Science.gov (United States)

    Pecquet, Catherine

    2013-01-01

    Some products derived from insects can induce allergic reactions. The main characteristics of some products from honeybees, cochineal and silkworms are summarised here. We review allergic reactions from honey-derived products (propolis, wax, royal jelly), from cochineal products (shellac and carmine) and from silk : clinical features, allergological investigations and allergens if they are known.

  5. Buckling failures in insect exoskeletons.

    Science.gov (United States)

    Parle, Eoin; Herbaj, Simona; Sheils, Fiona; Larmon, Hannah; Taylor, David

    2016-02-01

    Thin walled tubes are often used for load-bearing structures, in nature and in engineering, because they offer good resistance to bending and torsion at relatively low weight. However, when loaded in bending they are prone to failure by buckling. It is difficult to predict the loading conditions which cause buckling, especially for tubes whose cross sections are not simple shapes. Insights into buckling prevention might be gained by studying this phenomenon in the exoskeletons of insects and other arthropods. We investigated the leg segments (tibiae) of five different insects: the locust (Schistocerca gergaria), American cockroach (Periplaneta americana), death's head cockroach (Blaberus discoidalis), stick insect (Parapachymorpha zomproi) and bumblebee (Bombus terrestris audax). These were tested to failure in cantilever bending and modelled using finite element analysis (FEA). The tibiae of the locust and the cockroaches were found to be approximately circular in shape. Their buckling loads were well predicted by linear elastic FEA, and also by one of the analytical solutions available in the literature for elastic buckling. The legs of the stick insect are also circular in cross section but have several prominent longitudinal ridges. We hypothesised that these ridges might protect the legs against buckling but we found that this was not the case: the loads necessary for elastic buckling were not reached in practice because yield occurred in the material, causing plastic buckling. The legs of bees have a non-circular cross section due to a pollen-carrying feature (the corbicula). We found that this did not significantly affect their resistance to buckling. Our results imply that buckling is the dominant failure mode in the tibia of insects; it likely to be a significant consideration for other arthropods and any organisms with stiff exoskeletons. The interactions displayed here between material properties and cross sectional geometry may provide insights for the

  6. 21 CFR 1250.95 - Insect control.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be... generally accepted methods of insect control....

  7. Genetics of insect resistance to plant defence

    NARCIS (Netherlands)

    Vermeer, K.M.C.A.

    2014-01-01

      Plants are chemically defended against insect herbivory in various ways. They produce a broad range of secondary metabolites that may be toxic or deterrent to insects. Specialist insects, however, are often capable of overcoming these defences. The yellow striped flea beetle (Phyllotreta nem

  8. Insect Control (1): Use of Pheromones

    Science.gov (United States)

    Marx, Jean L.

    1973-01-01

    Discusses current research relating to the use of pheromones as a means of controlling insect pests. These chemicals, which are secreted by insects to affect the behavior of other individuals of the same species, may be used to eliminate pests without destroying their predators and other beneficial insects. (JR)

  9. Genetics of insect resistance to plant defence

    NARCIS (Netherlands)

    Vermeer, K.M.C.A.

    2014-01-01

      Plants are chemically defended against insect herbivory in various ways. They produce a broad range of secondary metabolites that may be toxic or deterrent to insects. Specialist insects, however, are often capable of overcoming these defences. The yellow striped flea beetle (Phyllotreta nem

  10. Radar, Insect Population Ecology, and Pest Management

    Science.gov (United States)

    Vaughn, C. R. (Editor); Wolf, W. (Editor); Klassen, W. (Editor)

    1979-01-01

    Discussions included: (1) the potential role of radar in insect ecology studies and pest management; (2) the potential role of radar in correlating atmospheric phenomena with insect movement; (3) the present and future radar systems; (4) program objectives required to adapt radar to insect ecology studies and pest management; and (5) the specific action items to achieve the objectives.

  11. Genetics of insect resistance to plant defence

    NARCIS (Netherlands)

    Vermeer, K.M.C.A.

    2014-01-01

      Plants are chemically defended against insect herbivory in various ways. They produce a broad range of secondary metabolites that may be toxic or deterrent to insects. Specialist insects, however, are often capable of overcoming these defences. The yellow striped flea beetle (Phyllotreta

  12. Insect Control (1): Use of Pheromones

    Science.gov (United States)

    Marx, Jean L.

    1973-01-01

    Discusses current research relating to the use of pheromones as a means of controlling insect pests. These chemicals, which are secreted by insects to affect the behavior of other individuals of the same species, may be used to eliminate pests without destroying their predators and other beneficial insects. (JR)

  13. Plant responses to insect egg deposition

    NARCIS (Netherlands)

    Hilker, M.; Fatouros, N.E.

    2015-01-01

    Plants can respond to insect egg deposition and thus resist attack by herbivorous insects from the beginning of the attack, egg deposition. We review ecological effects of plant responses to insect eggs and differentiate between egg-induced plant defenses that directly harm the eggs and indirect

  14. Plant responses to insect egg deposition

    NARCIS (Netherlands)

    Hilker, M.; Fatouros, N.E.

    2015-01-01

    Plants can respond to insect egg deposition and thus resist attack by herbivorous insects from the beginning of the attack, egg deposition. We review ecological effects of plant responses to insect eggs and differentiate between egg-induced plant defenses that directly harm the eggs and indirect def

  15. 7 CFR 51.2122 - Insect injury.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the...

  16. 7 CFR 51.2290 - Insect injury.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury...

  17. 7 CFR 51.2008 - Insect injury.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means...

  18. Effects of 5%lmidacloprid Oil in Preventing Myzus persicae in Different Test Sites%5%吡虫啉乳油不同试验点防治烟蚜田间药效试验研究

    Institute of Scientific and Technical Information of China (English)

    沈运河

    2014-01-01

    ln the research, 5% imidacloprid oil at different doses were applied to prevent Myzus persicae in order to explore significance analysis in 3, 7, 14, and 20 d, respectively, in three fields, and the results showed that 5% imidacloprid oil per-formed significant for K326, G28 and Yunyan-87, suggesting 5% imidacloprid oil is effective in control ing Myzus persicae.%该文对5%吡虫啉乳油对烟草烟蚜进行3地田间药效试验,通过对不同剂量5%吡虫啉乳油,在药后3、7、14、20 d进行差异显著性分析。结果表明5%吡虫啉乳油对烟草K326、烟草 G28、云烟-87防效效果较好。证明5%吡虫啉对烟蚜有较好的防治效果。

  19. Insect biofuel cells using trehalose included in insect hemolymph leading to an insect-mountable biofuel cell.

    Science.gov (United States)

    Shoji, Kan; Akiyama, Yoshitake; Suzuki, Masato; Hoshino, Takayuki; Nakamura, Nobuhumi; Ohno, Hiroyuki; Morishima, Keisuke

    2012-12-01

    In this paper, an insect biofuel cell (BFC) using trehalose included in insect hemolymph was developed. The insect BFC is based on trehalase and glucose oxidase (GOD) reaction systems which oxidize β-glucose obtained by hydrolyzing trehalose. First, we confirmed by LC-MS that a sufficient amount of trehalose was present in the cockroach hemolymph (CHL). The maximum power density obtained using the insect BFC was 6.07 μW/cm(2). The power output was kept more than 10 % for 2.5 h by protecting the electrodes with a dialysis membrane. Furthermore, the maximum power density was increased to 10.5 μW/cm(2) by using an air diffusion cathode. Finally, we succeeded in driving a melody integrated circuit (IC) and a piezo speaker by connecting five insect BFCs in series. The results indicate that the insect BFC is a promising insect-mountable battery to power environmental monitoring micro-tools.

  20. Insect stereopsis demonstrated using a 3D insect cinema.

    Science.gov (United States)

    Nityananda, Vivek; Tarawneh, Ghaith; Rosner, Ronny; Nicolas, Judith; Crichton, Stuart; Read, Jenny

    2016-01-07

    Stereopsis - 3D vision - has become widely used as a model of perception. However, all our knowledge of possible underlying mechanisms comes almost exclusively from vertebrates. While stereopsis has been demonstrated for one invertebrate, the praying mantis, a lack of techniques to probe invertebrate stereopsis has prevented any further progress for three decades. We therefore developed a stereoscopic display system for insects, using miniature 3D glasses to present separate images to each eye, and tested our ability to deliver stereoscopic illusions to praying mantises. We find that while filtering by circular polarization failed due to excessive crosstalk, "anaglyph" filtering by spectral content clearly succeeded in giving the mantis the illusion of 3D depth. We thus definitively demonstrate stereopsis in mantises and also demonstrate that the anaglyph technique can be effectively used to deliver virtual 3D stimuli to insects. This method opens up broad avenues of research into the parallel evolution of stereoscopic computations and possible new algorithms for depth perception.

  1. Insect stereopsis demonstrated using a 3D insect cinema

    OpenAIRE

    Vivek Nityananda; Ghaith Tarawneh; Ronny Rosner; Judith Nicolas; Stuart Crichton; Jenny Read

    2016-01-01

    Stereopsis - 3D vision – has become widely used as a model of perception. However, all our knowledge of possible underlying mechanisms comes almost exclusively from vertebrates. While stereopsis has been demonstrated for one invertebrate, the praying mantis, a lack of techniques to probe invertebrate stereopsis has prevented any further progress for three decades. We therefore developed a stereoscopic display system for insects, using miniature 3D glasses to present separate images to each ey...

  2. Extreme adaptations for aquatic ectoparasitism in a Jurassic fly larva.

    Science.gov (United States)

    Chen, Jun; Wang, Bo; Engel, Michael S; Wappler, Torsten; Jarzembowski, Edmund A; Zhang, Haichun; Wang, Xiaoli; Zheng, Xiaoting; Rust, Jes

    2014-06-24

    The reconstruction of ancient insect ectoparasitism is challenging, mostly because of the extreme scarcity of fossils with obvious ectoparasitic features such as sucking-piercing mouthparts and specialized attachment organs. Here we describe a bizarre fly larva (Diptera), Qiyia jurassica gen. et sp. nov., from the Jurassic of China, that represents a stem group of the tabanomorph family Athericidae. Q. jurassica exhibits adaptations to an aquatic habitat. More importantly, it preserves an unusual combination of features including a thoracic sucker with six radial ridges, unique in insects, piercing-sucking mouthparts for fluid feeding, and crocheted ventral prolegs with upward directed bristles for anchoring and movement while submerged. We demonstrate that Q. jurassica was an aquatic ectoparasitic insect, probably feeding on the blood of salamanders. The finding reveals an extreme morphological specialization of fly larvae, and broadens our understanding of the diversity of ectoparasitism in Mesozoic insects.DOI: http://dx.doi.org/10.7554/eLife.02844.001.

  3. The Curious Connection Between Insects and Dreams

    OpenAIRE

    Klein, Barrett A.

    2011-01-01

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psyc...

  4. Insect diversity in the fossil record

    Science.gov (United States)

    Labandeira, C. C.; Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)

    1993-01-01

    Insects possess a surprisingly extensive fossil record. Compilation of the geochronologic ranges of insect families demonstrates that their diversity exceeds that of preserved vertebrate tetrapods through 91 percent of their evolutionary history. The great diversity of insects was achieved not by high origination rates but rather by low extinction rates comparable to the low rates of slowly evolving marine invertebrate groups. The great radiation of modern insects began 245 million years ago and was not accelerated by the expansion of angiosperms during the Cretaceous period. The basic trophic machinery of insects was in place nearly 100 million years before angiosperms appeared in the fossil record.

  5. Fungal allelochemicals in insect pest management.

    Science.gov (United States)

    Holighaus, Gerrit; Rohlfs, Marko

    2016-07-01

    Interactions between insects and fungi are widespread, and important mediators of these interactions are fungal chemicals that can therefore be considered as allelochemicals. Numerous studies suggest that fungal chemicals can affect insects in many different ways. Here, we apply the terminology established by insect-plant ecologists for categorizing the effect of fungal allelochemicals on insects and for evaluating the application potential of these chemicals in insect pest management. Our literature survey shows that fungal volatile and non-volatile chemicals have an enormous potential to influence insect behavior and fitness. Many of them still remain to be discovered, but some recent examples of repellents and toxins could open up new ways for developing safe insect control strategies. However, we also identified shortcomings in our understanding of the chemical ecology of insect-fungus interactions and the way they have been investigated. In particular, the mode-of-action of fungal allelochemicals has often not been appropriately designated or examined, and the way in which induction by insects affects fungal chemical diversity is poorly understood. This review should raise awareness that in-depth ecological studies of insect-fungus interactions can reveal novel allelochemicals of particular benefit for the development of innovative insect pest management strategies.

  6. 75 FR 47592 - Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other...

    Science.gov (United States)

    2010-08-06

    ... AGENCY Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other... Product Performance of Skin-applied Insect Repellents of Insect and Other Arthropods Test Guidelines... ``Product Performance of Skin-applied Insect Repellents of Insects and Other Arthropods'' (OPPTS...

  7. Insect immune resistance to parasitoids

    Institute of Scientific and Technical Information of China (English)

    Yves Carton; Marylène Poirié; Anthony J. Nappi

    2008-01-01

    Insect host-parasitoid interactions involve complex physiological, biochemical and genetic interactions. Against endoparasitoids, immune-competent hosts initiate a blood cell-mediated response that quickly destroys the intruders and envelops them in a multilayered melanotic capsule. During the past decade, considerable progress has been made in identifying some of the critical components of the host response, mainly because of the use of efficient molecular tools. This review examines some of the components of the innate immune response of Drosophila, an insect that has served as an exceptionally good experimental model for studying non-self recognition processes and immune cell signaling mechanisms. Topics considered in this review include hematopoiesis, proliferation and adhesion of hemocytes, melanogenesis and associated cytotoxic molecules, and the genetic aspects of the host-parasitoid interaction.

  8. Immunity in a Social Insect

    Science.gov (United States)

    Rosengaus, Rebeca B.; Traniello, James F. A.; Chen, Tammy; Brown, Julie J.; Karp, Richard D.

    Although pathogens appear to have exerted significant selective pressure on various aspects of sociality, mechanisms of disease resistance in the social insects are poorly understood. We report here on an immune response to infection by the dampwood termite, Zootermopsis angusticollis. Nymphs immunized with an injection of 7.6×107, 7.6×105, or 7.6×104 cells/ml glutaraldehyde-killed solution of the bacterium Pseudomonas aeruginosa had significantly higher survivorship than controls following a challenge with a lethal concentration of active bacteria. Similarly, nymphs exposed to a 9×10-1 spores/ml suspension of the fungus Metarhizium anisopliae had higher survivorship than controls after a challenge with a lethal concentration of spores. Prior exposure to a pathogen thus conferred upon termites a degree of protection during a subsequent encounter with the same pathogen. This represents the first demonstration of immune function in vivo in a social insect.

  9. Visual homing: an insect perspective.

    Science.gov (United States)

    Zeil, Jochen

    2012-04-01

    The ability to learn the location of places in the world and to revisit them repeatedly is crucial for all aspects of animal life on earth. It underpins animal foraging, predator avoidance, territoriality, mating, nest construction and parental care. Much theoretical and experimental progress has recently been made in identifying the sensory cues and the computational mechanisms that allow insects (and robots) to find their way back to places, while the neurobiological mechanisms underlying navigational abilities are beginning to be unravelled in vertebrate and invertebrate models. Studying visual homing in insects is interesting, because they allow experimentation and view-reconstruction under natural conditions, because they are likely to have evolved parsimonious, yet robust solutions to the homing problem and because they force us to consider the viewpoint of navigating animals, including their sensory and computational capacities. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. The Insect SNMP Gene Family

    Science.gov (United States)

    2009-01-01

    B 1 ( b o v ) Clade 3 - SNMPs Clade 2 Clade 1 CD36 Insect (Holometabola) CD36 Gene family Holometabola Phylogeny (11 Orders) Tribolium castaneum...melanogaster genes (see Nichols and Vogt, 2008). Bootstrap support (1000 replicates) is indicated for the major clades. B. Phylogeny of holometabolous...A. aegypti eggs were graciously provided by Mark Brown (University of Georgia, Department of Entomology) and raised on a larval diet (pond fish food

  11. Sensory Coordination of Insect Flight

    Science.gov (United States)

    2010-10-22

    migratory flight in the neotropical moth Urania fulgens. Biology Letters, 6, 406–409. Sane S.P.* and McHenry M.J. (2009) The biomechanics of sensory...organs. Integrative and Comparative Biology , 49(6):i8-i23. Zhao, L., Huang, Q., Deng, X. and Sane, S.P. (2010). Aerodynamic effects of flexibility...and behavioral insights into insect flight Invited Speaker, International Workshop on Nocturnal Pollination , March 24-27, 2009 Indian Institute of

  12. Benzoquinolinediones: activity as insect teratogens

    Energy Technology Data Exchange (ETDEWEB)

    Walton, B.T.; Ho, C.H.; Ma, C.Y.; O' Neill, E.G.; Kao, G.L.

    1983-10-28

    Morphological abnormalities including extra compound eyes, extra heads, and distally duplicated legs were generated in cricket embryos by treating eggs with single doses of either benz(g)isoquinoline-5,10-dione or benzo(h)quinoline-5,6-dione. Slight structural modifications of the molecules resulted in a loss of teratogenic activity, although embryotoxicity occurred. These potent insect teratogens can be used for analysis of developmental events during embryogenesis. 13 references, 4 figures, 1 table.

  13. Biophysique environnementale des insectes endophytes.

    OpenAIRE

    2005-01-01

    Physiology and life history traits of ectothermic organisms depend on microclimate temperature. In some insect - plant relationships, the herbivore manipulates physically and /or chemically its proximate environment, i.e. plant tissues. The effects of such modifications on the phytophage's microclimate are however still poorly understood. We investigated the physical modifications of apple leaf tissues made by the leaf mining moth Phyllonorycter blancardella (Lepidoptera: Gracillariidae), and...

  14. The insect cellular immune response

    Institute of Scientific and Technical Information of China (English)

    Michael R. Strand

    2008-01-01

    The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understanding of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources: progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources of a number of humoral effector molecules required for killing different foreign invaders.

  15. Evolutionary diversification of insect innexins.

    Science.gov (United States)

    Hughes, Austin L

    2014-01-01

    Phylogenetic analysis of insect innexins supported the hypothesis that six major clades of insect innexins arose by gene duplication prior to the origin of the endopterygote insects. Within one of the six clades (the Zpg Clade), two independent gene duplication events were inferred to have occurred in the lineage of Drosophila, after the most recent common ancestor of the dipteran families Culicidae and Drosophilidae. The relationships among this clades were poorly resolved, except for a sister relationship between ShakB and Ogre. Gene expression data from FlyAtlas supported the hypothesis that the latter gene duplication events gave rise to functional differentiation, with Zpg showing a high level of expression in ovary, and Inx5 and Inx6 showing a high level of expression in testis. Because unduplicated members of this clade in Bombyx mori and Anopheles gambiae showed high levels of expression in both ovary and tests, the expression patterns of the Drosophila members of this clade provide evidence of subdivision of an ancestral gene function after gene duplication. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  16. Stiffness of desiccating insect wings

    Energy Technology Data Exchange (ETDEWEB)

    Mengesha, T E; Vallance, R R [Department of Mechanical Engineering, The George Washington University, 738 Phillips Hall, 801 22nd St NW, Washington, DC 20052 (United States); Mittal, R, E-mail: vallance@gwu.edu [Department of Mechanical Engineering, Johns Hopkins University, 126 Latrobe Hall, 3400 N Charles Street, Baltimore, MD 21218 (United States)

    2011-03-15

    The stiffness of insect wings is typically determined through experimental measurements. Such experiments are performed on wings removed from insects. However, the wings are subject to desiccation which typically leads to an increase in their stiffness. Although this effect of desiccation is well known, a comprehensive study of the rate of change in stiffness of desiccating insect wings would be a significant aid in planning experiments as well as interpreting data from such experiments. This communication presents a comprehensive experimental analysis of the change in mass and stiffness of gradually desiccating forewings of Painted Lady butterflies (Vanessa cardui). Mass and stiffness of the forewings of five butterflies were simultaneously measured every 10 min over a 24 h period. The averaged results show that wing mass declined exponentially by 21.1% over this time period with a time constant of 9.8 h, while wing stiffness increased linearly by 46.2% at a rate of 23.4 {mu}N mm{sup -1} h{sup -1}. For the forewings of a single butterfly, the experiment was performed over a period of 1 week, and the results show that wing mass declined exponentially by 52.2% with a time constant of 30.2 h until it reached a steady-state level of 2.00 mg, while wing stiffness increased exponentially by 90.7% until it reached a steady-state level of 1.70 mN mm{sup -1}. (communication)

  17. Comparative analysis of Solanum stoloniferum responses to probing by the green peach aphid Myzus persicae and the potato aphid Macrosiphum euphorbiae

    Institute of Scientific and Technical Information of China (English)

    Adriana E.Alvarez; Viviana G.Broglia; Anahí M.Alberti D'Amato; Doret Wouters; Edwin van der Vossen; Elisa Garzo; W.Fred Tjallingii

    2013-01-01

    Plants protect themselves against aphid attacks by species-specific defense mechanisms.Previously,we have shown that Solanum stoloniferum Schlechtd has resistance factors to Myzus persicae Sulzer (Homoptera:Aphididae) at the epidermal/mesophyll level that are not effective against Macrosiphum euphorbiae Thomas (Homoptera:Aphididae).Here,we compare the nymphal mortality,the pre-reproductive development time,and the probing behavior of M.persicae and M.euphorbiae on S.stoloniferum and Solanum tuberosum L.Furthermore,we analyze the changes in gene expression in S.stoloniferum 96 hours post infestation by either aphid species.Although the M.euphorbiae probing behavior shows that aphids encounter more probing constrains on phloem activities-longer probing and salivation time-on S.stoloniferum than on S.tuberosum,the aphids succeeded in reaching a sustained ingestion of phloem sap on both plants.Probing by M.persicae on S.stoloniferum plants resulted in limited feeding only.Survival of M.euphorbiae and M.persicae was affected on young leaves,but not on senescent leaves of S.stoloniferum.Infestation by M.euphorbiae changed the expression of more genes than M.persicae did.At the systemic level both aphids elicited a weak response.Infestation of S.stoloniferum plants with a large number ofM.persicae induced morphological changes in the leaves,leading to the development of pustules that were caused by disrupted vascular parenchyma and surrounding tissue.In contrast,an infestation by M.euphorbiae had no morphological effects.Both plant species can be regarded as good host for M.euphorbiae,whereas only S.tuberosum is a good host for Mo persicae and S.stoloniferum is not.Infestation of S.stoloniferum by M.persicae or M.euphorbiae changed the expression of a set of plant genes specific for each of the aphids as well as a set of common genes.

  18. The influence of aphids (Myzus persicae) and pink lady beetle larvae (Coleomegilla maculata) on host plant preference of imported cabbageworm (Pieris rapae)

    Science.gov (United States)

    Oviposition decisions by herbivorous insects hinge on multiple factors; host plant quality, enemy free space, plant density, offspring performance, and competition for resources all which influence decisions by an ovipositing female. Here, we evaluate whether the presence of aphids (a competitor) or...

  19. Geostatistics and GIS analysis of spatial patterns of Myzus persicae and Hylyphantes graminicola in peach orchards under chemical pesticide stress%基于地统计学和 GIS 的化学农药胁迫下桃树桃蚜与草间钻头蛛种群空间格局

    Institute of Scientific and Technical Information of China (English)

    蒋杰贤; 万年峰; 季香云

    2015-01-01

    The overuse of chemical pesticides not only kills insect pests and natural enemies, but also affects the spatial relationship between insect pests and their natural enemies. Hylyphantes graminicola is a key predator of Myzus persicae in peach orchard eosystems. In this paper, we systematically investigated M. persicae and its predator H. graminicola populations in peach orchards under chemical pesticide stress at different times (from mid April to early September), used geostatistics and geographic information system (GIS) to analyze the spatial structure, and used ordinary Kriging interpretation with Gaussian, Exponential, Spherical and Circular models to simulate the spatial distribution of the two species.The aim of the study was to understand the spacial distribution of M. persicae and its predator H. graminicola under long-term applicaiton of chemical pestcides and provide the theoretical support for ecological control of peach garden pests. The results suggested that both H. graminicola and M. persicae had random spatial arrangement within 10 iterative times of investigations. The proportions of spatical sturcture [C0/(C+ C0)] of populations of H. graminicola and M. persicae were 0.788 8-0.983 9 and 0.811 6-0.980 6 indicating weak spacial relathship bewteen two populaitons under long-term chemical pestcide stress. The nugget values and partial sills of H. Graminicola, M. persicae were respectivel 0.254 2-4.896 3, 0.218 4-0.749 9 and 0.010 5-0.250 0, 0.004 8-0.075 7, respectively, indicating random spatial arrangement, too. Thecorrelation of spatial distribution distance of two species was relatively weak, the distance ranges for the two species was 6.863 0-43.174 1 m. Though the model parameters of semivariograms for M. persicae and H. graminicola at different times were changed greatly due to population density, temperature, and peach growth, the spatial patterns of the two populations were random under long-term chemical pesticide stress. Our study

  20. Research on predatory function reaction of three species ladybirds to wildMyzus persicae andHyalopterus arundimis%3种瓢虫对野生型桃蚜和桃粉蚜的捕食功能反应

    Institute of Scientific and Technical Information of China (English)

    任向辉; 杨萌; 李鹏; 陈燕飞; 汪治鹏; 刘婉婉; 白钰; 刘迎春; 陈丹丹

    2015-01-01

    The indoor predatory function reactions of the main natural enemies includingCoccinella septempunctata, Propylea japonica andLeis axyridis to the wildMyzus persicae andHyalopterus arundimis were studied in this paper. The results showed that the type of functional responses was Holling’s type II with the temperature of 25℃. By using disc equations regression with improved simplex method, the attack coefficients of three species ladybirds toMyzus persicae were 1.53953, 1.64510 and 1.28469 respectively, but the values toHyalopterus arundimis were 1.33421, 1.18244 and 1.12258 respectively. Furthermore, the handling time values of three species ladybirds toMyzus persicae were 0.02392, 0.02747 and 0.00908 respectively, and the values toHyalopterus arundimis were 0.01381, 0.01476 and 0.01056 respectively. In conclusion these parameters would provide the guidance for the biocontrol of these aphides.%研究桃树蚜虫的主要捕食性天敌七星瓢虫、龟纹瓢虫和异色瓢虫对野生型桃蚜和桃粉蚜个体的室内捕食功能反应,发现25℃条件下3种瓢虫的成虫的捕食功能反应类型为Hol ingI 型。圆盘方程加速单纯形法回归分析表明,七星瓢虫、龟纹瓢虫和异色瓢虫对桃蚜无翅成蚜的攻击系数依次为1.53953、1.64510、1.28469,而对桃粉蚜无翅成蚜的攻击系数依次为1.33421、1.18244、1.12258;此外,七星瓢虫、龟纹瓢虫和异色瓢虫对桃蚜无翅成蚜的处理时间依次为0.02392、0.02747、0.00908,而对桃粉蚜无翅成蚜的处理时间依次为0.01381、0.01476、0.01056。这些参数为两种蚜虫的生物防治提供了理论指导。

  1. Herbivory increases diversification across insect clades.

    Science.gov (United States)

    Wiens, John J; Lapoint, Richard T; Whiteman, Noah K

    2015-09-24

    Insects contain more than half of all living species, but the causes of their remarkable diversity remain poorly understood. Many authors have suggested that herbivory has accelerated diversification in many insect clades. However, others have questioned the role of herbivory in insect diversification. Here, we test the relationships between herbivory and insect diversification across multiple scales. We find a strong, positive relationship between herbivory and diversification among insect orders. However, herbivory explains less variation in diversification within some orders (Diptera, Hemiptera) or shows no significant relationship with diversification in others (Coleoptera, Hymenoptera, Orthoptera). Thus, we support the overall importance of herbivory for insect diversification, but also show that its impacts can vary across scales and clades. In summary, our results illuminate the causes of species richness patterns in a group containing most living species, and show the importance of ecological impacts on diversification in explaining the diversity of life.

  2. Insects

    OpenAIRE

    Brewster, Carlyle C.; Miller, Dini M.; Polanco, Andrea M.

    2011-01-01

    Four bed bug strains (Cimex lectularius) with different levels of pyrethroid resistance were evaluated to determine their ability to survive extended periods of starvation. First instar bed bugs of all strains were the most vulnerable to starvation (13.8–36.3 days mean survival time). Fifth instars and adults survived the longest during starvation (41.5–142.6 days). Significant differences in survivorship during starvation were observed between resistant and susceptible strains of bed bugs. O...

  3. Impacts of urbanization process on insect diversity

    OpenAIRE

    Shuisong Ye; Yan Fang; Kai Li

    2013-01-01

    Rapid worldwide urbanization during the last century has led to more than half the world’s population living in urban regions. Studies of how urbanization affects insect diversity have focused on the following: insect abundance, distribution, extinction, food habits and ecosystem services. Native insect populations have declined greatly in urban areas, where studies of their spatial distribution have revealed that abundance decreases along what is termed the rural–city center gradient (RCG), ...

  4. Evolutionary genetics of insect innate immunity

    OpenAIRE

    Viljakainen, Lumi

    2015-01-01

    Patterns of evolution in immune defense genes help to understand the evolutionary dynamics between hosts and pathogens. Multiple insect genomes have been sequenced, with many of them having annotated immune genes, which paves the way for a comparative genomic analysis of insect immunity. In this review, I summarize the current state of comparative and evolutionary genomics of insect innate immune defense. The focus is on the conserved and divergent components of immunity with an emphasis on g...

  5. Insect Repellent Properties of Melaleuca alternifolia

    OpenAIRE

    Mohamad Adib Bin Edris; Awang Soh Yusuff Mamat; Muhammad Shahzad Aslam; Muhammad Syarhabil Ahmad

    2016-01-01

    The aim of this study is to compare the use of plant-based insect repellents that are environment friendly with the use of insect repellents based on chemical substances which can be harmful to the environment and human health. The plant studied here is "tea tree"; its scientific name is Melaleuca alternifolia. Essential oil from this plant is extracted by steam distillation method. Based on the previous research, tea tree oil has antimicrobial, antifungal, anti-inflammatory, and insect repel...

  6. Converting pest insects into food

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim; Wiwatwittaya, Decha

    2010-01-01

    on management, 32-115 kg ant brood (mainly new queens) was harvested per ha per year without detrimental effect on colony survival and worker ant densities. This suggest that ant biocontrol and ant harvest can be sustainable integrated in plantations and double benefits derived. As ant production is fuelled...... by pest insects, problematic pests are converted into food and additional earnings. To assess the profitability of providing additional food for the ants, O. smaragdina food conversion efficiency (ECI) was estimated in the laboratory. This estimate suggests the feeding of weaver ants in ant farms...

  7. Converting pest insects into food

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim; Wiwatwittaya, Decha

    2010-01-01

    Canopy dwelling weaver ants (Oecophylla spp.) are used to control a variety of pests in a number of tropical tree crops. What is less familiar is the existence of commercial markets where these ants and their brood are sold for (i) human consumption, (ii) pet food or (iii) traditional medicine...... by pest insects, problematic pests are converted into food and additional earnings. To assess the profitability of providing additional food for the ants, O. smaragdina food conversion efficiency (ECI) was estimated in the laboratory. This estimate suggests the feeding of weaver ants in ant farms...

  8. Delayed insect access alters carrion decomposition and necrophagous insect community assembly

    Science.gov (United States)

    Vertebrate carrion in terrestrial ecosystems is an unpredictable, ephemeral resource pulse that contributes to local biodiversity and nutrient transformation dynamics. We hypothesized that delayed insect access to carrion would demonstrate marked shifts in necrophagous insect community structure, t...

  9. Review on Nutritive Value of Edible Insects

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    As an importam bio-resource, insect resources have not been put into full play as healthy food. Based on study and analysis, the nutritive value of edible insects was reviewed. The results showed that insects have rich protein (20%-70%), amino acid (30%-60%),fat (10%-50%),fatty acid, carbonhydrate (2%-10%), mineral elements, vitamins and other activated elements which are good for human 's health. As protein resources, the nutritive value of edible insects is as good as animal and plant resources. Insec...

  10. Contemporary frontiers in insect semiochemical research.

    Science.gov (United States)

    Tumlinson, J H

    1988-11-01

    Recent advances in analytical chemistry coupled with more definitive behavioral analyses have allowed more rigorous identification of many insect pheromones. This, in turn, has increased our understanding of the roles of pheromones in mediating insect behavior. Other semiochemicals that mediate insect behavior include those that enable parasitic and predatory insects to locate their hosts or prey. These may be produced by the host insects or by the plant on which they feed. Additionally, there are pheromones and plant-produced seminochemicals that regulate insect oviposition, a critical phase in the life cycle of insects. The challenge to chemists and biologists is to explore these areas to find new environmentally safe methods to control insect pests. One of the newer strategies used to investigate these semiochemicals is the study of the biochemistry of pheromone production and semiochemical perception in insects. These types of studies may reveal weak links in these systems that can be exploited to develop new, more effective and environmentally safe control methods.

  11. Predicting the potential establishment of two insect species using the simulation environment INSIM (INsect SIMulation)

    NARCIS (Netherlands)

    Hemerik, Lia; Nes, van Egbert H.

    2016-01-01

    Degree-day models have long been used to predict events in the life cycle of insects and therewith the timing of outbreaks of insect pests and their natural enemies. This approach assumes, however, that the effect of temperature is linear, whereas developmental rates of insects are non-linearly

  12. Insects diversity in lima bean (Phaseolus lunatus

    Directory of Open Access Journals (Sweden)

    WIWIN SETIAWATI

    2005-10-01

    Full Text Available Lima bean (Phaseolus lunatus is a vegetable which usually made as a home yard plant for Indonesian people to fulfill their daily needs. This plant has not been produced in the large number by the farmer. So it is hard to find in the market. Lima bean is light by many kind of insect. Inventory, identification and the study of insect taxon to this plant is being done to collect some information about the insect who life in the plant. The research was done in Balitsa experiment garden in the district of Lembang in Bandung regency on November 2003-February 2004, the experiment start at 4 weeks age, at the height of 1260 m over the sea level. The observation was made systematically by absolute method (D-vac macine and relative method (sweeping net. The research so that there were 26 species of phytofagous insect, 9 species of predator insect, 6 species of parasitoid insect, 4 species of pollinator and 14 species of scavenger insect. According to the research the highest species number was got in the 8th week (3rd sampling, which had 27 variety of species, so the highest diversity was also got in this with 2,113 point. Aphididae and Cicadellidae was the most insect found in roay plant. The research also had high number of species insect so the diversity of insect and evenness become high. A community will have the high stability if it is a long with the high diversity. High evenness in community that has low species dominance and high species number of insect so the high of species richness.

  13. Chemosterilants for Control of Insects and Insect Vectors of Disease.

    Science.gov (United States)

    Baxter, Richard H G

    2016-10-01

    Both historically and at present, vector control is the most generally effective means of controlling malaria transmission. Insecticides are the predominant method of vector control, but the sterile insect technique (SIT) is a complementary strategy with a successful track record in both agricultural and public health sectors. Strategies of genetic and radiation-induced sterilization of Anopheles have to date been limited by logistical and/or regulatory hurdles. A safe and effective mosquito chemosterilant would therefore be of major utility to future deployment of SIT for malaria control. Here we review the prior and current use of chemosterilants in SIT, and assess the potential for future research. Recent genomic and proteomic studies reveal opportunities for specific targeting of seminal fluid proteins, and the capacity to interfere with sperm motility and storage in the female.

  14. Study of drimane sesquiterpenoids from the Persicaria genus and zigiberene from Callitropsis noorkatensis and their effect on the feeding behaviour of Myzus persicae and Bemisia tabaci

    NARCIS (Netherlands)

    Prota, N.

    2015-01-01

    Summary Whitefly is an insect pest that has systematically spread into colder latitudes for the past two decades and it poses a serious threat to crops, mainly due to the viruses for which it acts as a vector. As the applica

  15. Study of drimane sesquiterpenoids from the Persicaria genus and zigiberene from Callitropsis noorkatensis and their effect on the feeding behaviour of Myzus persicae and Bemisia tabaci

    NARCIS (Netherlands)

    Prota, N.

    2015-01-01

    Summary Whitefly is an insect pest that has systematically spread into colder latitudes for the past two decades and it poses a serious threat to crops, mainly due to the viruses for which it acts as a vector. As the applica

  16. Diversity in protein glycosylation among insect species.

    Directory of Open Access Journals (Sweden)

    Gianni Vandenborre

    Full Text Available BACKGROUND: A very common protein modification in multicellular organisms is protein glycosylation or the addition of carbohydrate structures to the peptide backbone. Although the Class of the Insecta is the largest animal taxon on Earth, almost all information concerning glycosylation in insects is derived from studies with only one species, namely the fruit fly Drosophila melanogaster. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the differences in glycoproteomes between insects belonging to several economically important insect orders were studied. Using GNA (Galanthus nivalis agglutinin affinity chromatography, different sets of glycoproteins with mannosyl-containing glycan structures were purified from the flour beetle (Tribolium castaneum, the silkworm (Bombyx mori, the honeybee (Apis mellifera, the fruit fly (D. melanogaster and the pea aphid (Acyrthosiphon pisum. To identify and characterize the purified glycoproteins, LC-MS/MS analysis was performed. For all insect species, it was demonstrated that glycoproteins were related to a broad range of biological processes and molecular functions. Moreover, the majority of glycoproteins retained on the GNA column were unique to one particular insect species and only a few glycoproteins were present in the five different glycoprotein sets. Furthermore, these data support the hypothesis that insect glycoproteins can be decorated with mannosylated O-glycans. CONCLUSIONS/SIGNIFICANCE: The results presented here demonstrate that oligomannose N-glycosylation events are highly specific depending on the insect species. In addition, we also demonstrated that protein O-mannosylation in insect species may occur more frequently than currently believed.

  17. Edible insects contributing to food security?

    NARCIS (Netherlands)

    Huis, van Arnold

    2015-01-01

    Because of growing demand for meat and declining availability of agricultural land, there is an urgent need to find alternative protein sources. Edible insects can be produced with less environmental impact than livestock. Insect meal can replace scarce fishmeal as feed ingredient, in particular

  18. Potential applications of insect symbionts in biotechnology.

    Science.gov (United States)

    Berasategui, Aileen; Shukla, Shantanu; Salem, Hassan; Kaltenpoth, Martin

    2016-02-01

    Symbiotic interactions between insects and microorganisms are widespread in nature and are often the source of ecological innovations. In addition to supplementing their host with essential nutrients, microbial symbionts can produce enzymes that help degrade their food source as well as small molecules that defend against pathogens, parasites, and predators. As such, the study of insect ecology and symbiosis represents an important source of chemical compounds and enzymes with potential biotechnological value. In addition, the knowledge on insect symbiosis can provide novel avenues for the control of agricultural pest insects and vectors of human diseases, through targeted manipulation of the symbionts or the host-symbiont associations. Here, we discuss different insect-microbe interactions that can be exploited for insect pest and human disease control, as well as in human medicine and industrial processes. Our aim is to raise awareness that insect symbionts can be interesting sources of biotechnological applications and that knowledge on insect ecology can guide targeted efforts to discover microorganisms of applied value.

  19. Insects and Spiders. Environmental Education Curriculum.

    Science.gov (United States)

    Topeka Public Schools, KS.

    This unit is designed to provide information on insects and spiders that special education students are capable of understanding. The activities are aimed at level 2 and level 3 educable mentally retarded classes. There are four topics: (1) Characteristics and Life Cycles of Insects; (2) Characteristics of Spiders; (3) Habitats and Food Sources of…

  20. Edible insects contributing to food security?

    NARCIS (Netherlands)

    Huis, van Arnold

    2015-01-01

    Because of growing demand for meat and declining availability of agricultural land, there is an urgent need to find alternative protein sources. Edible insects can be produced with less environmental impact than livestock. Insect meal can replace scarce fishmeal as feed ingredient, in particular

  1. Towards the elements of successful insect RNAi.

    Science.gov (United States)

    Scott, Jeffrey G; Michel, Kristin; Bartholomay, Lyric C; Siegfried, Blair D; Hunter, Wayne B; Smagghe, Guy; Zhu, Kun Yan; Douglas, Angela E

    2013-12-01

    RNA interference (RNAi), the sequence-specific suppression of gene expression, offers great opportunities for insect science, especially to analyze gene function, manage pest populations, and reduce disease pathogens. The accumulating body of literature on insect RNAi has revealed that the efficiency of RNAi varies between different species, the mode of RNAi delivery, and the genes being targeted. There is also variation in the duration of transcript suppression. At present, we have a limited capacity to predict the ideal experimental strategy for RNAi of a particular gene/insect because of our incomplete understanding of whether and how the RNAi signal is amplified and spread among insect cells. Consequently, development of the optimal RNAi protocols is a highly empirical process. This limitation can be relieved by systematic analysis of the molecular physiological basis of RNAi mechanisms in insects. An enhanced conceptual understanding of RNAi function in insects will facilitate the application of RNAi for dissection of gene function, and to fast-track the application of RNAi to both control pests and develop effective methods to protect beneficial insects and non-insect arthropods, particularly the honey bee (Apis mellifera) and cultured Pacific white shrimp (Litopenaeus vannamei) from viral and parasitic diseases.

  2. Modeling resistance to genetic control of insects.

    Science.gov (United States)

    Alphey, Nina; Bonsall, Michael B; Alphey, Luke

    2011-02-07

    The sterile insect technique is an area-wide pest control method that reduces pest populations by releasing mass-reared sterile insects which compete for mates with wild insects. Modern molecular tools have created possibilities for improving and extending the sterile insect technique. As with any new insect control method, questions arise about potential resistance. Genetic RIDL(®)(1) (Release of Insects carrying a Dominant Lethal) technology is a proposed modification of the technique, releasing insects that are homozygous for a repressible dominant lethal genetic construct rather than being sterilized by irradiation. Hypothetical resistance to the lethal mechanism is a potential threat to RIDL strategies' effectiveness. Using population genetic and population dynamic models, we assess the circumstances under which monogenic biochemically based resistance could have a significant impact on the effectiveness of releases for population control. We assume that released insects would be homozygous susceptible to the lethal genetic construct and therefore releases would have a built-in element of resistance dilution. We find that this effect could prevent or limit the spread of resistance to RIDL constructs; the outcomes are subject to competing selective forces deriving from the fitness properties of resistance and the release ratio. Resistance that is spreading and capable of having a significant detrimental impact on population reduction is identifiable, signaling in advance a need for mitigating action.

  3. Eicosanoids: Progress Toward Manipulating Insect Immunity

    Science.gov (United States)

    Insect immunity is exclusively innate, lacking the antibody-based adaptive immunity of vertebrates. Innate immunity is a naturally occurring, non-specific system that does not require previous infectious experience. In this essay I describe insect immunity and review the roles of prostaglandins an...

  4. Applications of genome editing in insects

    Science.gov (United States)

    Insect genome editing was first reported 1991 in Drosophila melanogaster but the technology used was not portable to other species. Not until the recent development of facile, engineered DNA endonuclease systems has gene editing become widely available to insect scientists. Most applications in inse...

  5. What Do Elementary Students Know about Insects?

    Science.gov (United States)

    Barrow, Lloyd H.

    2002-01-01

    Presents an interview-based study of (n=56) elementary school students. Determines students' understanding about insect characteristics, life cycles, environmental conditions, and impact on humans. Suggests building units of instruction based on students' personal questions about insects. (Contains 16 references.) (Author/YDS)

  6. Notes on collecting flower-visiting insects

    NARCIS (Netherlands)

    Willemstein, S.C.

    1974-01-01

    Flower-visiting insects may play a role in the pollination of the flowers they visit. An important indication for this is the pollen they carry on their body. The transport of pollen does not prove pollination without observations of the behaviour of the insects on the flowers, but at least it offer

  7. Testing mechanistic models of growth in insects.

    Science.gov (United States)

    Maino, James L; Kearney, Michael R

    2015-11-22

    Insects are typified by their small size, large numbers, impressive reproductive output and rapid growth. However, insect growth is not simply rapid; rather, insects follow a qualitatively distinct trajectory to many other animals. Here we present a mechanistic growth model for insects and show that increasing specific assimilation during the growth phase can explain the near-exponential growth trajectory of insects. The presented model is tested against growth data on 50 insects, and compared against other mechanistic growth models. Unlike the other mechanistic models, our growth model predicts energy reserves per biomass to increase with age, which implies a higher production efficiency and energy density of biomass in later instars. These predictions are tested against data compiled from the literature whereby it is confirmed that insects increase their production efficiency (by 24 percentage points) and energy density (by 4 J mg(-1)) between hatching and the attainment of full size. The model suggests that insects achieve greater production efficiencies and enhanced growth rates by increasing specific assimilation and increasing energy reserves per biomass, which are less costly to maintain than structural biomass. Our findings illustrate how the explanatory and predictive power of mechanistic growth models comes from their grounding in underlying biological processes.

  8. Notes on collecting flower-visiting insects

    NARCIS (Netherlands)

    Willemstein, S.C.

    1974-01-01

    Flower-visiting insects may play a role in the pollination of the flowers they visit. An important indication for this is the pollen they carry on their body. The transport of pollen does not prove pollination without observations of the behaviour of the insects on the flowers, but at least it

  9. Beneficial Insects and Spiders of Alaska

    Science.gov (United States)

    The development of integrated pest management programs is dependent on the availability of biological information on beneficial insects and natural enemies of agricultural pests. This cooperative effort between ARS and UAF represents the first manual on beneficial insects and natural enemies of pest...

  10. Estimating Aquatic Insect Populations. Introduction to Sampling.

    Science.gov (United States)

    Chihuahuan Desert Research Inst., Alpine, TX.

    This booklet introduces high school and junior high school students to the major groups of aquatic insects and to population sampling techniques. Chapter 1 consists of a short field guide which can be used to identify five separate orders of aquatic insects: odonata (dragonflies and damselflies); ephemeroptera (mayflies); diptera (true flies);…

  11. Insect vision: controlling actions through optic flow.

    Science.gov (United States)

    Collett, Thomas S

    2002-09-17

    Insects depend upon optic flow to supply much of their information about the three-dimensional structure of the world. Many insects use translational flow to measure the distance of objects from themselves. A recent study has provided new insights into the way Drosophila use optic flow to pick out a close target to approach.

  12. Endocrine disruption in aquatic insects: a review.

    Science.gov (United States)

    Soin, Thomas; Smagghe, Guy

    2007-02-01

    There is mounting evidence that a wide variety of compounds can have endocrine disrupting effects on humans and wildlife. However, investigations so far have focused primarily on exposure to human and other vertebrates, with invertebrate findings largely restricted to marine mollusks or to the ecdysteroid and juvenile hormone agonists as purposely synthesized endocrine disrupters for the pest management of insects. This article provides a brief description of the insect hormone system, a short sum-up of the relevant insect groups with aquatic life stages, and an overview of the additional evidence for endocrine disruption in aquatic insects from laboratory and field studies since 1999. In addition, the suitability of insects as sentinels for endocrine disrupting chemicals in aquatic ecosystems is discussed. Conclusions are drawn and research needs are defined.

  13. Insect Vectors of Rice Yellow Mottle Virus

    Directory of Open Access Journals (Sweden)

    Augustin Koudamiloro

    2015-01-01

    Full Text Available Rice yellow mottle virus (RYMV is the major viral constraint to rice production in Africa. RYMV was first identified in 1966 in Kenya and then later in most African countries where rice is grown. Several studies have been conducted so far on its evolution, pathogenicity, resistance genes, and especially its dissemination by insects. Many of these studies showed that, among RYMV vectors, insects especially leaf-feeders found in rice fields are the major source of virus transmission. Many studies have shown that the virus is vectored by several insect species in a process of a first ingestion of leaf material and subsequent transmission in following feedings. About forty insect species were identified as vectors of RYMV since 1970 up to now. They were essentially the beetles, grasshoppers, and the leafhoppers. For this review, we presented the chronology of their identification. Also, the biology, ecology, host range, distribution, and caused damage of these insects were briefly summarized.

  14. A call to insect scientists: Challenges and opportunities of managing insect communities under climate change

    Science.gov (United States)

    Hellmann, Jessica J.; Grundel, Ralph; Hoving, Chris; Schuurman, Gregor W.

    2016-01-01

    As climate change moves insect systems into uncharted territory, more knowledge about insect dynamics and the factors that drive them could enable us to better manage and conserve insect communities. Climate change may also require us revisit insect management goals and strategies and lead to a new kind of scientific engagement in management decision-making. Here we make five key points about the role of insect science in aiding and crafting management decisions, and we illustrate those points with the monarch butterfly and the Karner blue butterfly, two species undergoing considerable change and facing new management dilemmas. Insect biology has a strong history of engagement in applied problems, and as the impacts of climate change increase, a reimagined ethic of entomology in service of broader society may emerge. We hope to motivate insect biologists to contribute time and effort toward solving the challenges of climate change.

  15. A call to insect scientists: challenges and opportunities of managing insect communities under climate change.

    Science.gov (United States)

    Hellmann, Jessica J; Grundel, Ralph; Hoving, Chris; Schuurman, Gregor W

    2016-10-01

    As climate change moves insect systems into uncharted territory, more knowledge about insect dynamics and the factors that drive them could enable us to better manage and conserve insect communities. Climate change may also require us to revisit insect management goals and strategies and lead to a new kind of scientific engagement in management decision-making. Here we make five key points about the role of insect science in aiding and crafting management decisions, and we illustrate those points with the monarch butterfly and the Karner blue butterfly, two species undergoing considerable change and facing new management dilemmas. Insect biology has a strong history of engagement in applied problems, and as the impacts of climate change increase, a reimagined ethic of entomology in service of broader society may emerge. We hope to motivate insect biologists to contribute time and effort toward solving the challenges of climate change. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Tin compounds and insect fauna

    Energy Technology Data Exchange (ETDEWEB)

    Butovskiy, R.O.

    1985-03-01

    A review of the literature of tin compounds serving as pesticides has resulted in the identification of 11 widely used compounds, both organic and inorganic, with largely fungicidal activity. Organotin compounds seem to be limited in use to the control of insect pests, with the majority of the compounds consisting of Sn(IV) and falling into the following four categories: R/sub 4/Sn, R/sub 3/SNX, R/sub 2/SnX/sub 2/, and RSnX/sub 3/, where R = aliphatic or aromatic hydrocarbon radicals, and X = organic or inorganic substituent. The insecticidal activity of these compounds appears to rest on inhibition of ATPase and uncoupling of oxidative phosphorylation. As a result, these compounds act as larvicides, ovicides and imagocides. 77 references.

  17. [Insect antimicrobial peptides: structures, properties and gene regulation].

    Science.gov (United States)

    Wang, Yi-Peng; Lai, Ren

    2010-02-01

    Insect antimicrobial peptides (AMPs) are an important group of insect innate immunity effectors. Insect AMPs are cationic and contain less than 100 amino acid residues. According to structure, insect AMPs can be divided into a limited number of families. The diverse antimicrobial spectrum of insect AMPs may indicate different modes of action. Research on the model organism Drosophila indicate that insect AMPs gene regulation involves multiple signaling pathways and a large number of signaling molecules.

  18. Modern Stored-Product Insect Pest Management

    Directory of Open Access Journals (Sweden)

    Hagstrum David William

    2014-07-01

    Full Text Available Stored-product entomologists have a variety of new monitoring, decision-making, biological, chemical, and physical pest management tools available to them. Two types of stored-product insect populations are of interest: insects of immediate economic importance infesting commodities, and insects that live in food residues in equipment and facilities. The sampling and control methods change as grain and grain products move from field to consumer. There are also some changes in the major insect pest species to take into consideration. In this review, we list the primary insect pests at each point of the marketing system, and indicate which sampling methods and control strategies are most appropriate. Economic thresholds for insect infestation levels developed for raw commodity storage, processing plants, and retail business allow sampling-based pest management to be done before insect infestations cause economic injury. Taking enough samples to have a representative sample (20-30 samples will generally provide enough information to classify a population as above or below an economic threshold.

  19. Induced resistance in rice against insects.

    Science.gov (United States)

    Karban, R; Chen, Y

    2007-08-01

    Vaccinations are the mainstay of western preventive medicine, and they have been used to protect some crops against disease and insect pests. We consider rice as a model for protection using induced resistance since it is one of the most important staple crops and there have been significant new developments in: cross-resistance among rice insects, chemical pathways involved in induced resistance, sequencing the rice genome and expression of genes conferring resistance against rice insect pests. Insect attack has been found to cause lesions that kill planthopper eggs and early stages of gall midges. Damaged plants released volatiles that made them less likely to be chosen by planthoppers and more attractive to parasitoids. Chemical elicitors have been developed for dicotyledonous plants and these can induce resistance in rice, although rice does not fit models developed to explain signalling in dicots. For example, salicylic acid did not increase in rice after infection by pathogens and did not appear to be the mobile signal for induced resistance against pathogens although it was involved in induced responses to phloem-feeding insects. Jasmonic acid acted as a signal in some induced responses to pathogens as well as chewing insects. Many of the genes associated with induced resistance in rice have recently been mapped, and techniques are being developed to incorporate them into the genome of cultivated varieties. Attempts to control insect pests of rice will affect interactions with pathogens, predators and parasites, and other organisms in this agroecosystem.

  20. Insect prophenoloxidase: the view beyond immunity

    Directory of Open Access Journals (Sweden)

    Anrui eLu

    2014-07-01

    Full Text Available Insect prophenoloxidase (PPO is an important innate immunity protein due to its involvement in cellular and humoral defense. It belongs to a group of type-3 copper-containing proteins that occurs in almost all organisms. Insect PPO has been studied for over a century, and the PPO activation cascade is becoming clearer. The insect PPO activation pathway incorporates several important proteins, including pattern-recognition receptors (PGRP, βGRP and C-type lectins, serine proteases, and serine protease inhibitors (serpins. Due to their complexity, PPO activation mechanisms vary among insect species. Activated phenoloxidase (PO oxidizes phenolic molecules to produce melanin around invading pathogens and wounds. The crystal structure of Manduca sexta PPO shows that a conserved amino acid, phenylalanine (F, can block the active site pocket. During activation, this blocker must be dislodged or even cleaved at the N-terminal sequence to expose the active site pockets and allow substrates to enter. Thanks to the crystal structure of M. sexta PPO, some domains and specific amino acids that affect PPO activities have been identified. Further studies of the relationship between PPO structure and enzyme activities will provide an opportunity to examine other type-3 copper proteins, and trace when and why their various physiological functions evolved. Recent researches show that insect PPO has a relationship with neuron activity, longevity, feces melanization (phytophagous insects and development, which suggests that it is time for us to look back on insect PPO beyond the view of immunity in this review.

  1. Insect-plant interactions: endocrine defences.

    Science.gov (United States)

    Bowers, W S

    1984-01-01

    It is the inevitable consequence of evolution that competitive species living together in a restricted space must try to exclude each other. Plants and insects are prime examples of this eternal competition, and although neither of these is in danger of extinction, their mutual defensive strategies are of compelling interest to the human race. Plant defences based on the insecticidal activity of certain of their secondary chemicals are readily apparent. Only through research into the fundamentals of insect physiology and biochemistry are more subtle defensive mechanisms revealed, linked to the disruption of the insect endocrine system. A diverse number of chemical structures are found in plants, which interfere with hormone-mediated processes in insects. Examples include: mimics of the insect's juvenile hormones such as juvabione from the balsam fir and the juvocimenes from sweet basil, which lethally disrupt insect development, and the precocenes found in Ageratum species, which act as anti-juvenile hormonal agents. The latter appear to serve as 'suicide substrates', undergoing activation into cytotoxins when acted on by specialized enzymes resident in the insect endocrine gland (corpus allatum) that is responsible for juvenile hormone biosynthesis and secretion. Consideration of these plant defensive strategies, which have been reached through aeons of evolutionary experimentation, may assist the human race in its defences against its principal competitors for food, fibre and health.

  2. Prostaglandins and their receptors in insect biology

    Directory of Open Access Journals (Sweden)

    David eStanley

    2011-12-01

    Full Text Available We treat the biological significance of prostaglandins (PGs and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. PGs act in several crucial areas of insect biology. In reproduction, a specific PG, PGE2, releases oviposition behavior in most crickets and a few other insect species; PGs also mediate events in egg development in some species, which may represent all insects. PGs play major roles in modulating fluid secretion in Malpighian tubules, rectum and salivary glands, although, again, this has been studied in only a few insect species that may represent the Class. Insect immunity is a very complex defense system. PGs and other eicosanoids mediate a large number of immune reactions to infection and invasion. The actions of most PGs are mediated by specific receptors. Biomedical research has discovered a great deal of knowledge about PG receptors in mammals, including their structures, pharmacology, molecular biology and cellular locations. Studies of PG receptors in insects lag behind the biomedical background, however, recent results hold the promise of accelerated research in this area. A PG receptor has been identified in a class of lepidopteran hemocytes and experimentally linked to the release of prophenoloxidase. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology.

  3. Evolutionary genetics of insect innate immunity.

    Science.gov (United States)

    Viljakainen, Lumi

    2015-11-01

    Patterns of evolution in immune defense genes help to understand the evolutionary dynamics between hosts and pathogens. Multiple insect genomes have been sequenced, with many of them having annotated immune genes, which paves the way for a comparative genomic analysis of insect immunity. In this review, I summarize the current state of comparative and evolutionary genomics of insect innate immune defense. The focus is on the conserved and divergent components of immunity with an emphasis on gene family evolution and evolution at the sequence level; both population genetics and molecular evolution frameworks are considered. © The Author 2015. Published by Oxford University Press.

  4. Technical Obstacles and Solutions for Myzus persicae Control by Large-scale Reproduction of Aphidius gifuensis%规模化应用烟蚜茧蜂防治烟蚜的主要技术障碍及应对方法

    Institute of Scientific and Technical Information of China (English)

    周子方; 任伟; 周冀衡; 邓小刚; 李春明; 陈发荣; 沈晗; 孙耿

    2011-01-01

    烟蚜Myzus persicae(Sulzer)是危害烟草Nicotina tobaccum L.的一种主要害虫,烟蚜茧蜂是烟蚜的优势寄生天敌.对烟蚜茧蜂控制烟蚜能力、繁殖技术、保护应用及规模化应用中需要研究的主要技术问题进行了分析,并总结了一些可供规模化应用烟蚜茧蜂防治烟蚜的解决方案.%Myzus persicae ( Sulzer) is a major pest for Nicotina tobaccum L. , while Aphidius gifuensis Aphidiidae is the parasitic natural enemy of Myzus persicae (Sulzer). The paper analyzes gome technical problems, such as the control capacity, reproductive technology, protection and large-scale application of Aphidius gifuensis, and introduces some available solutions to the large-scale application of Aphidius gifuensis in controlling M. Persicae.

  5. Insect Biochemistry Goes to School .

    Directory of Open Access Journals (Sweden)

    Leonardo R. Cunha

    2011-04-01

    Full Text Available Many arthropods feed on vertebrate blood and eventually transmit diseases to the human being. Ordinary citizens are continuously exposed to vectors of major diseases and thus prone to contamination. In the present study we have evaluated a new approach regarding the basic biochemistry mechanism that regulates thebiology of Triatominaes, well known as vectors of Chagas Disease. We have used a comic book "Carlos Chagas: 100 years of the discovery of a hero", produced by researchers at our laboratory. The main concepts presented include: neurochemistry of insect olfaction, hemostasis, blood digestion, redox balance to mention some. The material was applied between 60 pupils of theseventh year of elementary school. The work is divided into two phases: an assessment of the concepts that thestudents bring their experiences into the classroom by producing conceptual maps followed by the intervention with the comic and production ofnew conceptual maps under the influence of activity with the material. Analysis of 18conceptual maps obtained from 06 different groups at three different points revealedthat the average score 07 at the beginning of theevaluation went to an average of 45 at the end of the study. This result suggests that a change in the approach of content can give encouragement to students to better develop the theme of contributing to a proper process of conceptual change.

  6. TRANSGENIC PLANTS RESISTANT TO INSECTS

    Directory of Open Access Journals (Sweden)

    S. Kereša

    2009-09-01

    Full Text Available Proteinase inhibitors are secondary metabolites present in all plants and it seems that their major role is protection of plants against attacks of animals, insects and microorganisms. One of the family of proteinase inhibitors are squash inhibitors of serine proteinases purified from seeds belonging to genera Cucurbita, Cucumis and Momordica. Squash inhibitors consist of 29-32 amino acid residues and are considered to be the smallest inhibitors of the serine proteinases known. Because of shortness, genes for these inhibitors could be synthesised and modified at different ways. Modifications could lead to changes in inhibitor activity. Tobacco as a model plant was transformed with 12 different genes of squash inhibitors. Stable integration of transgenes in putative transgenic plants was determined by PCR analysis using genomic DNA and primers that anneal to promoter and terminator region. The first step of proteinase inhibitor gene expression in transgenic plants was revealed by RT-PCR analysis. In entomological tests where larvae were fed with leaves, influence of transgenic T0 plants, as well as non-transgenic control plants on retardation of larval growth of S. littoralis was examined. Results of entomological tests showed that it is possible to express squash proteinase inhibitors in plants at level that significantly reduces S. littoralis larval growth.

  7. Insect contamination protection for laminar flow surfaces

    Science.gov (United States)

    Croom, Cynthia C.; Holmes, Bruce J.

    1986-01-01

    The ability of modern aircraft surfaces to achieve laminar flow was well-accepted in recent years. Obtaining the maximum benefit of laminar flow for aircraft drag reduction requires maintaining minimum leading-edge contamination. Previously proposed insect contamination prevention methods have proved impractical due to cost, weight, or inconvenience. Past work has shown that insects will not adhere to water-wetted surfaces, but the large volumes of water required for protection rendered such a system impractical. The results of a flight experiment conducted by NASA to evaluate the performance of a porous leading-edge fluid discharge ice protection system operated as an insect contamination protections system are presented. In addition, these flights explored the environmental and atmospheric conditions most suitable for insect accumulation.

  8. Insect food aiming at Mars emigration

    Science.gov (United States)

    Katayama, Naomi; Yamashita, Masamichi; Hashimoto, Hirofumi; Nagasaka, Sanako; Kuwayama, Akemi; Sofue, Megumi

    2012-07-01

    We study insect food aiming at Mars emigration.In space agriculture, insect is the important creature which we cannot miss.It is necessary for the pollination of the plant, and it is rich to protein and lipid as food.I reported that silkworm is an insect necessary for astroponics in particular last time.We make clothes using silk thread, and the pupa becomes the food.In addition, the clothes can make food as protein when we need not to use it. The bee is a very important insect in the space agriculture,too.We examined nutrition of silkworm, bee, grasshopper, snail and the white ant which are necessary for Mars emigration.We will introduce of good balance space foods.We will report many meal menu for Mars emigration.

  9. Middle-scale navigation: the insect case

    OpenAIRE

    Wehner, R

    1996-01-01

    What is the large-scale spatial representation that insect foragers such as bees and ants form of their wider nest environs? This is the principal question which the following contributions aim to answer.

  10. Symbiont-mediated RNA interference in insects.

    Science.gov (United States)

    Whitten, Miranda M A; Facey, Paul D; Del Sol, Ricardo; Fernández-Martínez, Lorena T; Evans, Meirwyn C; Mitchell, Jacob J; Bodger, Owen G; Dyson, Paul J

    2016-02-24

    RNA interference (RNAi) methods for insects are often limited by problems with double-stranded (ds) RNA delivery, which restricts reverse genetics studies and the development of RNAi-based biocides. We therefore delegated to insect symbiotic bacteria the task of: (i) constitutive dsRNA synthesis and (ii) trauma-free delivery. RNaseIII-deficient, dsRNA-expressing bacterial strains were created from the symbionts of two very diverse pest species: a long-lived blood-sucking bug, Rhodnius prolixus, and a short-lived globally invasive polyphagous agricultural pest, western flower thrips (Frankliniella occidentalis). When ingested, the manipulated bacteria colonized the insects, successfully competed with the wild-type microflora, and sustainably mediated systemic knockdown phenotypes that were horizontally transmissible. This represents a significant advance in the ability to deliver RNAi, potentially to a large range of non-model insects.

  11. RNAi-mediated crop protection against insects.

    Science.gov (United States)

    Price, Daniel R G; Gatehouse, John A

    2008-07-01

    Downregulation of the expression of specific genes through RNA interference (RNAi), has been widely used for genetic research in insects. The method has relied on the injection of double-stranded RNA (dsRNA), which is not possible for practical applications in crop protection. By contrast, specific suppression of gene expression in nematodes is possible through feeding with dsRNA. This approach was thought to be unfeasible in insects, but recent results have shown that dsRNA fed as a diet component can be effective in downregulating targeted genes. More significantly, expression of dsRNA directed against suitable insect target genes in transgenic plants has been shown to give protection against pests, opening the way for a new generation of insect-resistant crops.

  12. Learning in Insect Pollinators and Herbivores.

    Science.gov (United States)

    Jones, Patricia L; Agrawal, Anurag A

    2017-01-31

    The relationship between plants and insects is influenced by insects' behavioral decisions during foraging and oviposition. In mutualistic pollinators and antagonistic herbivores, past experience (learning) affects such decisions, which ultimately can impact plant fitness. The higher levels of dietary generalism in pollinators than in herbivores may be an explanation for the differences in learning seen between these two groups. Generalist pollinators experience a high level of environmental variation, which we suggest favors associative learning. Larval herbivores employ habituation and sensitization-strategies useful in their less variable environments. Exceptions to these patterns based on habitats, mobility, and life history provide critical tests of current theory. Relevant plant traits should be under selection to be easily learned and remembered in pollinators and difficult to learn in herbivores. Insect learning thereby has the potential to have an important, yet largely unexplored, role in plant-insect coevolution.

  13. Biology of the CAPA peptides in insects.

    Science.gov (United States)

    Predel, R; Wegener, C

    2006-11-01

    CAPA peptides have been isolated from a broad range of insect species as well as an arachnid, and can be grouped into the periviscerokinin and pyrokinin peptide families. In insects, CAPA peptides are the characteristic and most abundant neuropeptides in the abdominal neurohemal system. In many species, CAPA peptides exert potent myotropic effects on different muscles such as the heart. In others, including blood-sucking insects able to transmit serious diseases, CAPA peptides have strong diuretic or anti-diuretic effects and thus are potentially of medical importance. CAPA peptides undergo cell-type-specific sorting and packaging, and are the first insect neuropeptides shown to be differentially processed. In this review, we discuss the current knowledge on the structure, distribution, receptors and physiological actions of the CAPA peptides.

  14. Cathepsins of lepidopteran insects: Aspects and prospects.

    Science.gov (United States)

    Saikhedkar, Nidhi; Summanwar, Aarohi; Joshi, Rakesh; Giri, Ashok

    2015-09-01

    Molecular understanding of lepidopteran physiology has revealed that proteases consist of one of the central regulatory/reacting system for insect growth and survival. Among the various proteases, cathepsins are the most crucial cellular proteases, which play vital roles during insect development. In the present review, we have discussed various aspects of the lepidopteran insect cathepsins, emphasizing their roles in processes like development, growth, metamorphosis, apoptosis and immunity. Cathepsins are categorized into different types on the basis of their sequence diversification, leading to variation in structure and catalytic function. Cathepsins exhibit tissue and stage specific expression pattern which is fine-tuned by a delicate balance of expression, compartmentalization, zymogen activation, inhibition by protein inhibitors and degradation. The indispensability of cathepsins as cellular proteases in the above mentioned processes proposes them as novel targets for designing effective and specific insect controlling strategies.

  15. Association mapping of plant resistance to insects.

    Science.gov (United States)

    Kloth, Karen J; Thoen, Manus P M; Bouwmeester, Harro J; Jongsma, Maarten A; Dicke, Marcel

    2012-05-01

    Association mapping is rapidly becoming an important method to explore the genetic architecture of complex traits in plants and offers unique opportunities for studying resistance to insect herbivores. Recent studies indicate that there is a trade-off between resistance against generalist and specialist insects. Most studies, however, use a targeted approach that will easily miss important components of insect resistance. Genome-wide association mapping provides a comprehensive approach to explore the whole array of plant defense mechanisms in the context of the generalist-specialist paradigm. As association mapping involves the screening of large numbers of plant lines, specific and accurate high-throughput phenotyping (HTP) methods are needed. Here, we discuss the prospects of association mapping for insect resistance and HTP requirements.

  16. Molecular evolutionary analyses of insect societies.

    Science.gov (United States)

    Fischman, Brielle J; Woodard, S Hollis; Robinson, Gene E

    2011-06-28

    The social insects live in extraordinarily complex and cohesive societies, where many individuals sacrifice their personal reproduction to become helpers in the colony. Identifying adaptive molecular changes involved in eusocial evolution in insects is important for understanding the mechanisms underlying transitions from solitary to social living, as well as the maintenance and elaboration of social life. Here, we review recent advances made in this area of research in several insect groups: the ants, bees, wasps, and termites. Drawing from whole-genome comparisons, candidate gene approaches, and a genome-scale comparative analysis of protein-coding sequence, we highlight novel insights gained for five major biological processes: chemical signaling, brain development and function, immunity, reproduction, and metabolism and nutrition. Lastly, we make comparisons across these diverse approaches and social insect lineages and discuss potential common themes of eusocial evolution, as well as challenges and prospects for future research in the field.

  17. Principles of Insect Identification. MP-20.

    Science.gov (United States)

    Lawson, Fred A.; Burkhardt, Chris C.

    This document provides information for the complete classification of members of the phylum Arthropoda. Both major and minor insect orders are discussed relative to their anatomical characteristics and importance. (CS)

  18. Insect Bites and Stings: First Aid

    Science.gov (United States)

    ... wasp, a hornet, a fire ant or a scorpion, can result in severe reactions. Some insects also ... Rapid heartbeat Hives Nausea, cramps or vomiting A scorpion sting and is a child Take these actions ...

  19. The Curious Connection Between Insects and Dreams

    National Research Council Canada - National Science Library

    Barrett A Klein

    ..., music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular...

  20. INSECT DIET OF SOME AFROTROPICAL INSECTIVOROUS ...

    African Journals Online (AJOL)

    Administrator

    requirements may limit populations and structure of communities. (Loiselle & Blake, 1991 ... grassland and scrub to farmlands and the few remaining patches of forest and ..... Insect species complex associated with Acacia senegalensis in the ...

  1. Comparative psychoneuroimmunology: evidence from the insects.

    Science.gov (United States)

    Adamo, Shelley A

    2006-09-01

    Interactions between immune systems, nervous systems, and behavior are well established in vertebrates. A comparative examination of these interactions in other animals will help us understand their evolution and present adaptive functions. Insects show immune-behavioral interactions similar to those seen in vertebrates, suggesting that many of them may have a highly conserved function. Activation of an immune response in insects results in illness-induced anorexia, behavioral fever, changes in reproductive behavior, and decreased learning ability in a broad range of species. Flight-or-fight behaviors result in a decline in disease resistance. In insects, illness-induced anorexia may enhance immunity. Stress-induced immunosuppression is probably due to physiological conflicts between the immune response and those of other physiological processes. Because insects occupy a wide range of ecological niches, they will be useful in examining how some immune-behavioral interactions are sculpted by an animal's behavioral ecology.

  2. Mechanics and aerodynamics of insect flight control.

    Science.gov (United States)

    Taylor, G K

    2001-11-01

    Insects have evolved sophisticated fight control mechanisms permitting a remarkable range of manoeuvres. Here, I present a qualitative analysis of insect flight control from the perspective of flight mechanics, drawing upon both the neurophysiology and biomechanics literatures. The current literature does not permit a formal, quantitative analysis of flight control, because the aerodynamic force systems that biologists have measured have rarely been complete and the position of the centre of gravity has only been recorded in a few studies. Treating the two best-known insect orders (Diptera and Orthoptera) separately from other insects, I discuss the control mechanisms of different insects in detail. Recent experimental studies suggest that the helicopter model of flight control proposed for Drosophila spp. may be better thought of as a facultative strategy for flight control, rather than the fixed (albeit selected) constraint that it is usually interpreted to be. On the other hand, the so-called 'constant-lift reaction' of locusts appears not to be a reflex for maintaining constant lift at varying angles of attack, as is usually assumed, but rather a mechanism to restore the insect to pitch equilibrium following a disturbance. Differences in the kinematic control mechanisms used by the various insect orders are related to differences in the arrangement of the wings, the construction of the flight motor and the unsteady mechanisms of lift production that are used. Since the evolution of insect flight control is likely to have paralleled the evolutionary refinement of these unsteady aerodynamic mechanisms, taxonomic differences in the kinematics of control could provide an assay of the relative importance of different unsteady mechanisms. Although the control kinematics vary widely between orders, the number of degrees of freedom that different insects can control will always be limited by the number of independent control inputs that they use. Control of the moments

  3. Synthesis of model compounds derived from natural clerodane insect antifeedants

    NARCIS (Netherlands)

    Klein Gebbinck, E.A.

    1999-01-01

    Insect antifeedants are compounds with the ability to reduce or inhibit insect feeding without directly killing the insect. Such compounds offer a number of properties that are highly desirable in environmentally friendly crop protection agents. Although the principle of insect control usin

  4. The role of mites in insect-fungus associations

    Science.gov (United States)

    R. W. Hofstetter; J. C. Moser

    2014-01-01

    The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on...

  5. Insects are Crawling in My Genital Warts

    OpenAIRE

    Jyoti Dhawan; Saurabh Singh; Somesh Gupta

    2011-01-01

    A 23-year-old woman presented with large exophytic genital wart arising from perineum, vulva, introitus of the vagina, and inner aspect of thighs. Patient developed severe itching and formication (insect-crawling sensation) in the lesions for past 1 week, though careful examination did not reveal any insects. Considering that the disease was causing psychological stress and physical symptoms, radiofrequency excision was planned. However, during the procedure, several maggots appeared from the...

  6. IMp: The customizable LEGO® Pinned Insect Manipulator

    Directory of Open Access Journals (Sweden)

    Steen Dupont

    2015-02-01

    Full Text Available We present a pinned insect manipulator (IMp constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble.

  7. Selectivity of Odorant Receptors in Insects

    Science.gov (United States)

    2012-07-13

    repellents do not elicit evolutionary adaptive behaviors in mosquitoes , but rather disrupt the final stages of host attraction (Figure 1B). It is...Dickens, J. C. (2010). Insect repellents : mod- ulators of mosquito odorant receptor activity. PLoS ONE 5, e12138. doi: 10.1371/journal.pone. 0012138...Multiple activities of insect repellents on odorant receptors in mosquitoes . Med. Vet. Entomol. 25, 436–444. Bohbot, J. D., Jones, P. L., Wang, G

  8. Linking energetics and overwintering in temperate insects.

    Science.gov (United States)

    Sinclair, Brent J

    2015-12-01

    Overwintering insects cannot feed, and energy they take into winter must therefore fuel energy demands during autumn, overwintering, warm periods prior to resumption of development in spring, and subsequent activity. Insects primarily consume lipids during winter, but may also use carbohydrate and proteins as fuel. Because they are ectotherms, the metabolic rate of insects is temperature-dependent, and the curvilinear nature of the metabolic rate-temperature relationship means that warm temperatures are disproportionately important to overwinter energy use. This energy use may be reduced physiologically, by reducing the slope or elevation of the metabolic rate-temperature relationship, or because of threshold changes, such as metabolic suppression upon freezing. Insects may also choose microhabitats or life history stages that reduce the impact of overwinter energy drain. There is considerable capacity for overwinter energy drain to affect insect survival and performance both directly (via starvation) or indirectly (for example, through a trade-off with cryoprotection), but this has not been well-explored. Likewise, the impact of overwinter energy drain on growing-season performance is not well understood. I conclude that overwinter energetics provides a useful lens through which to link physiology and ecology and winter and summer in studies of insect responses to their environment.

  9. Extracellular ice phase transitions in insects.

    Science.gov (United States)

    Hawes, T C

    2014-01-01

    At temperatures below their temperature of crystallization (Tc), the extracellular body fluids of insects undergo a phase transition from liquid to solid. Insects that survive the transition to equilibrium (complete freezing of the body fluids) are designated as freeze tolerant. Although this phenomenon has been reported and described in many Insecta, current nomenclature and theory does not clearly delineate between the process of transition (freezing) and the final solid phase itself (the frozen state). Thus freeze tolerant insects are currently, by convention, described in terms of the temperature at which the crystallization of their body fluids is initiated, Tc. In fact, the correct descriptor for insects that tolerate freezing is the temperature of equilibrium freezing, Tef. The process of freezing is itself a separate physical event with unique physiological stresses that are associated with ice growth. Correspondingly there are a number of insects whose physiological cryo-limits are very specifically delineated by this transitional envelope. The distinction also has considerable significance for our understanding of insect cryobiology: firstly, because the ability to manage endogenous ice growth is a fundamental segregator of cryotype; and secondly, because our understanding of internal ice management is still largely nascent.

  10. Insect Repellent Properties of Melaleuca alternifolia

    Directory of Open Access Journals (Sweden)

    Mohamad Adib Bin Edris

    2016-08-01

    Full Text Available The aim of this study is to compare the use of plant-based insect repellents that are environment friendly with the use of insect repellents based on chemical substances which can be harmful to the environment and human health. The plant studied here is "tea tree"; its scientific name is Melaleuca alternifolia. Essential oil from this plant is extracted by steam distillation method. Based on the previous research, tea tree oil has antimicrobial, antifungal, anti-inflammatory, and insect repellent properties. Some experiments were done on tea tree oil to determine its insect repellent properties and the suitable concentration that can be used to make sure its repelling effect is optimum. The purpose of this determination is to avoid its harmful effect on humans because it can be toxic if it is used at high concentration. The results showed that tea tree oil repelled Tribolium castaneum. Furthermore, the toxicity assays also gave positive result where the tea tree oil has toxic properties against Solenopsis invicta. The lethal dose (LD of tea tree oil to kill 50% of a group of S. invicta is 23.52 µL/mL. This LD50 is determined by using the arithmetic method of Karber. Broadly, the results showed that M. alternifolia has insect repellent properties and shows toxicity against certain insects.

  11. Tomographic Reconstruction of Neopterous Carboniferous Insect Nymphs

    Science.gov (United States)

    Garwood, Russell; Ross, Andrew; Sotty, Daniel; Chabard, Dominique; Charbonnier, Sylvain; Sutton, Mark; Withers, Philip J.

    2012-01-01

    Two new polyneopteran insect nymphs from the Montceau-les-Mines Lagerstätte of France are presented. Both are preserved in three dimensions, and are imaged with the aid of X-ray micro-tomography, allowing their morphology to be recovered in unprecedented detail. One–Anebos phrixos gen. et sp. nov.–is of uncertain affinities, and preserves portions of the antennae and eyes, coupled with a heavily spined habitus. The other is a roachoid with long antennae and chewing mouthparts very similar in form to the most generalized mandibulate mouthparts of extant orthopteroid insects. Computer reconstructions reveal limbs in both specimens, allowing identification of the segments and annulation in the tarsus, while poorly developed thoracic wing pads suggest both are young instars. This work describes the morphologically best-known Palaeozoic insect nymphs, allowing a better understanding of the juveniles’ palaeobiology and palaeoecology. We also consider the validity of evidence from Palaeozoic juvenile insects in wing origin theories. The study of juvenile Palaeozoic insects is currently a neglected field, yet these fossils provide direct evidence on the evolution of insect development. It is hoped this study will stimulate a renewed interest in such work. PMID:23049858

  12. Transgenic Tobacco Plants With Efficient Insect Resistance

    Institute of Scientific and Technical Information of China (English)

    李太元; 田颖川; 秦晓峰; 莽克强; 李文谷; 何永刚; 沈蕾

    1994-01-01

    Insecticidal protein gene CryIA(c)from Bacillus thuringiensis HD-1(B.t.toxin gene)with 5’-end modified and 3’-end deleted to 4 different lengths were inserted downstream of 35S promoterwith double enhancer and"Ω’"fragment of TMV-RNA cDNA in the binary vector pBin438 to constructthe chimeric expression vector of B.t.toxin gene.Leave stripes of tobacco plant var.NC89 widelygrown in China were transformed with A.tumefaciens LBA4404 harbouring the above expression vectorsrespectively,and kanamycin resistant tobacco plants were regenerated.Insect test with tobacco budwormH.assulta showed that insect-resistant transform.ants could be obtained from the regenerated plantstransformed with B.t.genes of different lengths though highest percentage(~50%)of plants with ahigh morality(90%-100%)to the testing insects is among those transformed with 1.8-kb toxin gene.Genetic,molecular and biological analyses of T1 and T2 progenies of plants with high efficient insect re-sistance showed that B.t.toxin gene and the character of insect resistance have been inherited in the pro-genies.Insect-resistant homozygotes D8-14 and D19-8 have been selected for small-scale field tests.

  13. Wetting Characteristics of Insect Wing Surfaces

    Institute of Scientific and Technical Information of China (English)

    Doyoung Byun; Jongin Hong; Saputra; Jin Hwan Ko; Young Jong Lee; Hoon Cheol Park; Bong-Kyu Byun; Jennifer R. Lukes

    2009-01-01

    Biological tiny structures have been observed on many kinds of surfaces such as lotus leaves, which have an effect on the coloration of Morpho butterflies and enhance the hydrophobicity of natural surfaces. We investigated the micro-scale and nano-scale structures on the wing surfaces of insects and found that the hierarchical multiple roughness structures help in enhancing the hydrophobicity. After examining 10 orders and 24 species of flying Pterygotan insects, we found that micro-scale and nano-scale structures typically exist on both the upper and lower wing surfaces of flying insects. The tiny structures such as denticle or setae on the insect wings enhance the hydrophobicity, thereby enabling the wings to be cleaned more easily. And the hydrophobic insect wings undergo a transition from Cassie to Wenzel states at pitch/size ratio of about 20. In order to examine the wetting characteristics on a rough surface, a biomimetic surface with micro-scale pillars is fabricated on a silicon wafer,which exhibits the same behavior as the insect wing, with the Cassie-Wenzel transition occurring consistently around a pitch/width value of 20.

  14. Tomographic reconstruction of neopterous carboniferous insect nymphs.

    Directory of Open Access Journals (Sweden)

    Russell Garwood

    Full Text Available Two new polyneopteran insect nymphs from the Montceau-les-Mines Lagerstätte of France are presented. Both are preserved in three dimensions, and are imaged with the aid of X-ray micro-tomography, allowing their morphology to be recovered in unprecedented detail. One-Anebos phrixos gen. et sp. nov.-is of uncertain affinities, and preserves portions of the antennae and eyes, coupled with a heavily spined habitus. The other is a roachoid with long antennae and chewing mouthparts very similar in form to the most generalized mandibulate mouthparts of extant orthopteroid insects. Computer reconstructions reveal limbs in both specimens, allowing identification of the segments and annulation in the tarsus, while poorly developed thoracic wing pads suggest both are young instars. This work describes the morphologically best-known Palaeozoic insect nymphs, allowing a better understanding of the juveniles' palaeobiology and palaeoecology. We also consider the validity of evidence from Palaeozoic juvenile insects in wing origin theories. The study of juvenile Palaeozoic insects is currently a neglected field, yet these fossils provide direct evidence on the evolution of insect development. It is hoped this study will stimulate a renewed interest in such work.

  15. International Symposium on Insect Physiology, Biochemistry and Molecular Biology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ We are building on the success of the Sixth Chinese Insect Physiology, Biochemistry and Molecular Biology Symposium, Beijing, held in 2005. The 2005 symposium saw many Chinese and international authorities share their expertise in a broad range of insect science, including analyses of insect genomes and proteomes, functional gene expression and regulation during development, insect immunity, insect neurobiology, insect-host interactions and insect chemical communication. The coming symposium, which will be held in Shandong University,Jinan, Shandong province, September 19-22, 2007, will offer material along similar lines.

  16. Wood Destroying Insects in Düzce Province

    OpenAIRE

    AKBULUT, Süleyman; KETEN, Akif; Yüksel, Beşir

    2008-01-01

    Wood destroying insects were investigated in forest depots, imported timbers, and wood products in use in Düzce province. In the collection of insect material trap logs, storage decks, and samples of wooden materials were used. In total, 63 insect species belonging to 31 families of 4 orders were found, and 34 of the identified species were categorized as pest species. In forest depots, the most common insects were bark beetles and longhorned beetles. Several wood-destroying insects were foun...

  17. Insect odorant receptors are molecular targets of the insect repellent DEET.

    Science.gov (United States)

    Ditzen, Mathias; Pellegrino, Maurizio; Vosshall, Leslie B

    2008-03-28

    DEET (N,N-diethyl-meta-toluamide) is the world's most widely used topical insect repellent, with broad effectiveness against most insects. Its mechanism of action and molecular target remain unknown. Here, we show that DEET blocks electrophysiological responses of olfactory sensory neurons to attractive odors in Anopheles gambiae and Drosophila melanogaster. DEET inhibits behavioral attraction to food odors in Drosophila, and this inhibition requires the highly conserved olfactory co-receptor OR83b. DEET inhibits odor-evoked currents mediated by the insect odorant receptor complex, comprising a ligand-binding subunit and OR83b. We conclude that DEET masks host odor by inhibiting subsets of heteromeric insect odorant receptors that require the OR83b co-receptor. The identification of candidate molecular targets for the action of DEET may aid in the design of safer and more effective insect repellents.

  18. Tritrophic interactions between transgenic potato expressing snowdrop lectin (GNA), an aphid pest (peach-potato aphid; Myzus persicae (Sulz.) and a beneficial predator (2-spot ladybird; Adalia bipunctata L.).

    Science.gov (United States)

    Down, Rachel E; Ford, Louise; Woodhouse, Stephen D; Davison, Gillian M; Majerus, Michael E N; Gatehouse, John A; Gatehouse, Angharad M R

    2003-04-01

    Tritrophic interactions between transgenic potato expressing the insecticidal lectin from snowdrop (Galanthus nivalis agglutinin; GNA), an aphid pest, Myzus persicae (Sulz.), and a beneficial predator, the 2-spot ladybird (Adalia bipunctata L.) were investigated. Clonal plants expressing GNA at 0.1-0.2% total soluble protein in leaves were used. No significant effects on development and survival of ladybird larvae fed on aphids from these transgenic plants were observed, with larval survival in the experimental group being 90% compared to 89% for controls. There were also no effects on subsequent female or male longevity. Female fecundity was also investigated. Although no significant differences (p > 0.05) were observed in egg production between control and experimental groups, a 10%, reduction (p < 0.01) in egg viability (determined by % hatch) occurred in ladybirds fed aphids reared on transgenic plants. Additional studies were carried out using aphids fed on artificial diet containing GNA, to deliver quantified levels of the protein to ladybird adults. GNA had no deleterious effects upon adult longevity, but resulted in a consistent trend for improved fecundity. Egg production was increased by up to 70% and egg viability also increased significantly. The results suggest that GNA is not deleterious to ladybirds. Results from these studies highlight the need to discriminate between direct and indirect effects when studying tritrophic interactions between plants/pests/natural enemies. Furthermore, it emphasises the importance of demonstrating 'cause and effect'.

  19. Insect cell culture in reagent bottles.

    Science.gov (United States)

    Rieffel, S; Roest, S; Klopp, J; Carnal, S; Marti, S; Gerhartz, B; Shrestha, B

    2014-01-01

    Growing insect cells with high air space in culture vessel is common from the early development of suspension cell culture. We believed and followed it with the hope that it allows sufficient air for optimal cell growth. However, we missed to identify how much air exactly cells need for its growth and multiplication. Here we present the innovative method that changed the way we run insect cell culture. The method is easy to adapt, cost-effective and useful for both academic and industrial research labs. We believe this method will revolutionize the way we run insect cell culture by increasing throughput in a cost-effective way. In our study we identified:•Insect cells need to be in suspension; air space in culture vessel and type of culture vessel is of less importance. Shaking condition that introduces small air bubbles and maintains it in suspension for longer time provides better oxygen transfer in liquid. For this, high-fill volume in combination with speed and shaking diameter are important.•Commercially available insect cells are not fragile as original isolates. These cells can easily withstand higher shaking speed.•Growth condition in particular lab set-up needs to be optimized. The condition used in one lab may not be optimum for another lab due to different incubators from different vendors.

  20. Insect antifeedant potent 9H-fluorenacylbromides

    Directory of Open Access Journals (Sweden)

    G. Thirunarayanan

    2013-04-01

    Full Text Available Background: Attempts to produce greener bromination of 2-acetyl 9H-fluorene with KBr+KBrO3 reagent using fly-ash:H2O catalyst in aqueous media gave 9H-fluorenacylbromides. Generally, the halo-keto compounds possess insect antifeedant activities. Therefore, the insect antifeedant activities of these acyl bromides have been studied using 4th instar larvae Achoea janata L against castor semilooper. Methods: Solvent free bromination method was used for synthesizing some 9H-fluorenacylbromides. They were characterized by UV, IR, NMR and mass spectroscopic data. Castor-leaf discs were used for evaluation of insect antifeedant activities of the synthesized acyl bromides. Results: The yields of synthesized acyl bromides were over 60%. The physical constants, analytical and spectral data of these ketones has been determined. Halo substituted acyl bromides gave good insect antifeedant activities. Conclusion: Easy handling, non-hazardous and environmentally benign bromination methods have been adopted for synthesizing acyl bromides with good yields. Bromo substituted acyl bromides show better insect antifeedant activity.

  1. Uncontrolled Stability in Freely Flying Insects

    Science.gov (United States)

    Melfi, James, Jr.; Wang, Z. Jane

    2015-11-01

    One of the key flight modes of a flying insect is longitudinal flight, traveling along a localized two-dimensional plane from one location to another. Past work on this topic has shown that flying insects, unless stabilized by some external stimulus, are typically unstable to a well studied pitching instability. In our work, we examine this instability in a computational study to understand whether it is possible for either evolution or an aero-vehicle designer to stabilize longitudinal flight through changes to insect morphology, kinematics, or aerodynamic quantities. A quasi-steady wingbeat averaged flapping flight model is used to describe the insect. From this model, a number of non-dimensional parameters are identified. The effect of these parameters was then quantified using linear stability analysis, applied to various translational states of the insect. Based on our understanding of these parameters, we demonstrate how to find an intrinsically stable flapping flight sequence for a dragonfly-like flapping flier in an instantaneous flapping flight model.

  2. Acoustic communication in insect disease vectors

    Directory of Open Access Journals (Sweden)

    Felipe de Mello Vigoder

    2013-01-01

    Full Text Available Acoustic signalling has been extensively studied in insect species, which has led to a better understanding of sexual communication, sexual selection and modes of speciation. The significance of acoustic signals for a blood-sucking insect was first reported in the XIX century by Christopher Johnston, studying the hearing organs of mosquitoes, but has received relatively little attention in other disease vectors until recently. Acoustic signals are often associated with mating behaviour and sexual selection and changes in signalling can lead to rapid evolutionary divergence and may ultimately contribute to the process of speciation. Songs can also have implications for the success of novel methods of disease control such as determining the mating competitiveness of modified insects used for mass-release control programs. Species-specific sound “signatures” may help identify incipient species within species complexes that may be of epidemiological significance, e.g. of higher vectorial capacity, thereby enabling the application of more focussed control measures to optimise the reduction of pathogen transmission. Although the study of acoustic communication in insect vectors has been relatively limited, this review of research demonstrates their value as models for understanding both the functional and evolutionary significance of acoustic communication in insects.

  3. Veins improve fracture toughness of insect wings.

    Directory of Open Access Journals (Sweden)

    Jan-Henning Dirks

    Full Text Available During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m. However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm. This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species.

  4. Shifting behaviour: epigenetic reprogramming in eusocial insects.

    Science.gov (United States)

    Patalano, Solenn; Hore, Timothy A; Reik, Wolf; Sumner, Seirian

    2012-06-01

    Epigenetic modifications are ancient and widely utilised mechanisms that have been recruited across fungi, plants and animals for diverse but fundamental biological functions, such as cell differentiation. Recently, a functional DNA methylation system was identified in the honeybee, where it appears to underlie queen and worker caste differentiation. This discovery, along with other insights into the epigenetics of social insects, allows provocative analogies to be drawn between insect caste differentiation and cellular differentiation, particularly in mammals. Developing larvae in social insect colonies are totipotent: they retain the ability to specialise as queens or workers, in a similar way to the totipotent cells of early embryos before they differentiate into specific cell lineages. Further, both differentiating cells and insect castes lose phenotypic plasticity by committing to their lineage, losing the ability to be readily reprogrammed. Hence, a comparison of the epigenetic mechanisms underlying lineage differentiation (and reprogramming) between cells and social insects is worthwhile. Here we develop a conceptual model of how loss and regain of phenotypic plasticity might be conserved for individual specialisation in both cells and societies. This framework forges a novel link between two fields of biological research, providing predictions for a unified approach to understanding the molecular mechanisms underlying biological complexity.

  5. Magnetoreception in eusocial insects: an update.

    Science.gov (United States)

    Wajnberg, Eliane; Acosta-Avalos, Daniel; Alves, Odivaldo Cambraia; de Oliveira, Jandira Ferreira; Srygley, Robert B; Esquivel, Darci M S

    2010-04-06

    Behavioural experiments for magnetoreception in eusocial insects in the last decade are reviewed. Ants and bees use the geomagnetic field to orient and navigate in areas around their nests and along migratory paths. Bees show sensitivity to small changes in magnetic fields in conditioning experiments and when exiting the hive. For the first time, the magnetic properties of the nanoparticles found in eusocial insects, obtained by magnetic techniques and electron microscopy, are reviewed. Different magnetic oxide nanoparticles, ranging from superparamagnetic to multi-domain particles, were observed in all body parts, but greater relative concentrations in the abdomens and antennae of honeybees and ants have focused attention on these segments. Theoretical models for how these specific magnetosensory apparatuses function have been proposed. Neuron-rich ant antennae may be the most amenable to discovering a magnetosensor that will greatly assist research into higher order processing of magnetic information. The ferromagnetic hypothesis is believed to apply to eusocial insects, but interest in a light-sensitive mechanism is growing. The diversity of compass mechanisms in animals suggests that multiple compasses may function in insect orientation and navigation. The search for magnetic compasses will continue even after a magnetosensor is discovered in eusocial insects.

  6. Neuropeptidergic regulation of reproduction in insects.

    Science.gov (United States)

    Van Wielendaele, Pieter; Badisco, Liesbeth; Vanden Broeck, Jozef

    2013-07-01

    Successful animal reproduction depends on multiple physiological and behavioral processes that take place in a timely and orderly manner in both mating partners. It is not only necessary that all relevant processes are well coordinated, they also need to be adjusted to external factors of abiotic and biotic nature (e.g. population density, mating partner availability). Therefore, it is not surprising that several hormonal factors play a crucial role in the regulation of animal reproductive physiology. In insects (the largest class of animals on planet Earth), lipophilic hormones, such as ecdysteroids and juvenile hormones, as well as several neuropeptides take part in this complex regulation. While some peptides can affect reproduction via an indirect action (e.g. by influencing secretion of juvenile hormone), others exert their regulatory activity by directly targeting the reproductive system. In addition to insect peptides with proven activities, several others were suggested to also play a role in the regulation of reproductive physiology. Because of the long evolutionary history of many insect orders, it is not always clear to what extent functional data obtained in a given species can be extrapolated to other insect taxa. In this paper, we will review the current knowledge concerning the neuropeptidergic regulation of insect reproduction and situate it in a more general physiological context.

  7. Flapping wing aerodynamics: from insects to vertebrates.

    Science.gov (United States)

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight.

  8. The rapidly changing landscape of insect phylogenetics.

    Science.gov (United States)

    Maddison, David R

    2016-12-01

    Insect phylogenetics is being profoundly changed by many innovations. Although rapid developments in genomics have center stage, key progress has been made in phenomics, field and museum science, digital databases and pipelines, analytical tools, and the culture of science. The importance of these methodological and cultural changes to the pace of inference of the hexapod Tree of Life is discussed. The innovations have the potential, when synthesized and mobilized in ways as yet unforeseen, to shine light on the million or more clades in insects, and infer their composition with confidence. There are many challenges to overcome before insects can enter the 'phylocognisant age', but because of the promise of genomics, phenomics, and informatics, that is now an imaginable future.

  9. Evolutionary interaction networks of insect pathogenic fungi.

    Science.gov (United States)

    Boomsma, Jacobus J; Jensen, Annette B; Meyling, Nicolai V; Eilenberg, Jørgen

    2014-01-01

    Lineages of insect pathogenic fungi are concentrated in three major clades: Hypocreales (several genera), Entomophthoromycota (orders Entomophthorales and Neozygitales), and Onygenales (genus Ascosphaera). Our review focuses on aspects of the evolutionary biology of these fungi that have remained underemphasized in previous reviews. To ensure integration with the better-known domains of insect pathology research, we followed a conceptual framework formulated by Tinbergen, asking complementary questions on mechanism, ontogeny, phylogeny, and adaptation. We aim to provide an introduction to the merits of evolutionary approaches for readers with a background in invertebrate pathology research and to make the insect pathogenic fungi more accessible as model systems for evolutionary biologists. We identify a number of questions in which fundamental research can offer novel insights into the evolutionary forces that have shaped host specialization and life-history traits such as spore number and size, somatic growth rate, toxin production, and interactions with host immune systems.

  10. Democratizing evolutionary biology, lessons from insects.

    Science.gov (United States)

    Dunn, Robert R; Beasley, DeAnna E

    2016-12-01

    The engagement of the public in the scientific process is an old practice. Yet with recent advances in technology, the role of the citizen scientist in studying evolutionary processes has increased. Insects provide ideal models for understanding these evolutionary processes at large scales. This review highlights how insect-based citizen science has led to the expansion of specimen collections and reframed research questions in light of new observations and unexpected discoveries. Given the rapid expansion of human-modified (and inhabited) environments, the degree to which the public can participate in insect-based citizen science will allow us to track and monitor evolutionary trends at a global scale. Copyright © 2016. Published by Elsevier Inc.

  11. RNA interference: Applications and advances in insect toxicology and insect pest management.

    Science.gov (United States)

    Kim, Young Ho; Soumaila Issa, Moustapha; Cooper, Anastasia M W; Zhu, Kun Yan

    2015-05-01

    Since its discovery, RNA interference (RNAi) has revolutionized functional genomic studies due to its sequence-specific nature of post-transcriptional gene silencing. In this paper, we provide a comprehensive review of the recent literature and summarize the current knowledge and advances in the applications of RNAi technologies in the field of insect toxicology and insect pest management. Many recent studies have focused on identification and validation of the genes encoding insecticide target proteins, such as acetylcholinesterases, ion channels, Bacillus thuringiensis receptors, and other receptors in the nervous system. RNAi technologies have also been widely applied to reveal the role of genes encoding cytochrome P450 monooxygenases, carboxylesterases, and glutathione S-transferases in insecticide detoxification and resistance. More recently, studies have focused on understanding the mechanism of insecticide-mediated up-regulation of detoxification genes in insects. As RNAi has already shown great potentials for insect pest management, many recent studies have also focused on host-induced gene silencing, in which several RNAi-based transgenic plants have been developed and tested as proof of concept for insect pest management. These studies indicate that RNAi is a valuable tool to address various fundamental questions in insect toxicology and may soon become an effective strategy for insect pest management.

  12. Insect vision as model for machine vision

    Science.gov (United States)

    Osorio, D.; Sobey, Peter J.

    1992-11-01

    The neural architecture, neurophysiology and behavioral abilities of insect vision are described, and compared with that of mammals. Insects have a hardwired neural architecture of highly differentiated neurons, quite different from the cerebral cortex, yet their behavioral abilities are in important respects similar to those of mammals. These observations challenge the view that the key to the power of biological neural computation is distributed processing by a plastic, highly interconnected, network of individually undifferentiated and unreliable neurons that has been a dominant picture of biological computation since Pitts and McCulloch's seminal work in the 1940's.

  13. The Evolution of Agriculture in Insects

    DEFF Research Database (Denmark)

    Mueller, Ulrich G.; Gerardo, Nicole M.; Aanen, Duur Kornelis

    2005-01-01

    Agriculture has evolved independently in three insect orders: once in ants, once in termites, and seven times in ambrosia beetles. Although these insect farmers are in some ways quite different from each other, in many more ways they are remarkably similar, suggesting convergent evolution. All......) sequester their gardens from the environment; (b) monitor gardens intensively, controlling pathogens early in disease outbreaks; (c) occasionally access population-level reservoirs of genetically variable cultivars, even while propagating clonal monocultures across many farmer generations; and (d) manage...

  14. Allergen immunotherapy for insect venom allergy

    DEFF Research Database (Denmark)

    Dhami, S; Zaman, H; Varga, E-M

    2016-01-01

    BACKGROUND: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines on Allergen Immunotherapy (AIT) for the management of insect venom allergy. To inform this process, we sought to assess the effectiveness, cost-effectiveness and safety...... of AIT in the management of insect venom allergy. METHODS: We undertook a systematic review, which involved searching 15 international biomedical databases for published and unpublished evidence. Studies were independently screened and critically appraised using established instruments. Data were...

  15. Aerodynamics of the Smallest Flying Insects

    CERN Document Server

    Miller, Laura A; Hedrick, Ty; Robinson, Alice; Santhanakrishnan, Arvind; Lowe, Audrey

    2011-01-01

    We present fluid dynamics videos of the flight of some of the smallest insects including the jewel wasp, \\textit{Ampulex compressa}, and thrips, \\textit{Thysanoptera} spp. The fruit fly, \\textit{Drosophila melanogaster}, is large in comparison to these insects. While the fruit fly flies at $Re \\approx 120$, the jewel wasp flies at $Re \\approx 60$, and thrips flies at $Re \\approx 10$. Differences in the general structures of the wakes generated by each species are observed. The differences in the wakes correspond to changes in the ratio of lift forces (vertical component) to drag forces (horizontal component) generated.

  16. Social insect symbionts: evolution in homeostatic fortresses

    DEFF Research Database (Denmark)

    Hughes, David P; Pierce, Naomi E; Boomsma, Jacobus J

    2008-01-01

    The massive environmentally buffered nests of some social insects can contain millions of individuals and a wide variety of parasites, commensals and mutualists. We suggest that the ways in which these homeostatic fortress environments affect the evolution of social insect symbionts are relevant...... for epidemiology, evolutionary biology and macroecology. We contend that specialized parasites will tend to become less virulent and mutualists less cooperative, compared to those associated with solitary or small-colony hosts. These processes are expected to contribute to the very high symbiont diversity observed...

  17. Selectivity of Odorant Receptors in Insects

    Directory of Open Access Journals (Sweden)

    Jonathan Daniel Bohbot

    2012-07-01

    Full Text Available Insect olfactory receptors (ORs detect chemicals, shape neuronal physiology and regulate behavior.  Although ORs have been categorized as generalists and specialists based on their ligand spectrum, both electrophysiological studies and recent pharmacological investigations show that ORs specifically recognize non-pheromonal compounds, and that our understanding of odorant-selectivity mirrors our knowledge of insect chemical ecology. As we are progressively becoming aware that ORs are activated through a variety of mechanisms, the molecular basis of odorant-selectivity and the corollary notion of broad-tuning need to be re-examined from a pharmacological and evolutionary perspective.

  18. In situ localization of proteinase inhibitor mRNA in rice plant challenged by brown planthopper

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Proteinase inhibitor (PI) mRNA was localized by in situ hybridization in tissue sections of root, stem and leaf of the resistant rice (B5) plant fed by brown planthopper nymphs. In the rice material without BPH feeding, PI gene was expressed in the root, stem and leaf, while the abundance of PI mRNA was low. In the rice material fed by BPH, PI gene was expressed substantially in the parenchyma of rice stem and leaf, but weakly in the root. The results indicated that the PI gene was up-regulated in the rice plant challenged by brown planthopper. For the first time, we reported the expression changes of proteinase inhibitor gene in plant which was infested by a piercing/sucking insect.

  19. Hormones and pheromones in regulation of insect behavior

    Science.gov (United States)

    Both pheromones and hormones are well recognized regulators of insect biology. However, the interactions between hormones and pheromones in coordinating insect biology are less well understood. We have studied the interactions between juvenile hormone, its precursor methyl farnesoate, and pheromon...

  20. Diseases in insects produced for food and feed

    DEFF Research Database (Denmark)

    Eilenberg, Jørgen; Vlak, J.M.; Nielsen-Leroux, C.

    2015-01-01

    Increased production of insects on a large scale for food and feed will likely lead to many novel challenges, including problems with diseases. We provide an overview of important groups of insect pathogens, which can cause disease in insects produced for food and feed. Main characteristics of each...... pathogen group (viruses, bacteria, fungi, protists and nematodes) are described and illustrated, with a selection of examples from the most commonly produced insect species for food and feed. Honeybee and silkworm are mostly produced for other reasons than as human food, yet we can still use them...... as examples to learn about emergence of new diseases in production insects. Results from a 2014 survey about insect diseases in current insect production systems are presented for the first time. Finally, we give some recommendations for the prevention and control of insect diseases. Key words: disease...

  1. Guild composition and seasonal distribution of insects on Protea ...

    African Journals Online (AJOL)

    1990-06-12

    Jun 12, 1990 ... test of Lawton's (1983) hypothesis that plant height is of significance in ... (PI). Species are grouped by guild, then taxon. (PS = phytophagous sucker, PC ..... Detritivores. No. insects. No.insects .40,--_ _ _ _ _ _ _ _ _ _ _---, .. 0.

  2. The role of mites in insect-fungus associations.

    Science.gov (United States)

    Hofstetter, R W; Moser, J C

    2014-01-01

    The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on fungi for nutrients, and fungi benefit from them with regard to spore dispersal, habitat provision, or nutrient resources. Mites have important impacts on community dynamics, ecosystem processes, and biodiversity within many insect-fungus systems. Given that mites are understudied but highly abundant, they likely have bigger, more important, and more widespread impacts on communities than previously recognized. We describe mutualistic and antagonistic effects of mites on insect-fungus associations, explore the processes that underpin ecological and evolutionary patterns of these multipartite communities, review well-researched examples of the effects of mites on insect-fungus associations, and discuss approaches for studying mites within insect-fungus communities.

  3. Molecular mechanisms of phenotypic plasticity in social insects

    Science.gov (United States)

    Polyphenism in insects, whereby a single genome expresses different phenotypes in response to environmental cues, is a fascinating biological phenomenon. Social insects are especially intriguing examples of phenotypic plasticity because division of labor results in the development of extreme morphol...

  4. Asymmetric radar echo patterns from insects

    Science.gov (United States)

    Radar echoes from insects, birds, and bats in the atmosphere exhibit both symmetry and asymmetry in polarimetric patterns. Symmetry refers to similar magnitudes of polarimetric variables at opposite azimuths, and asymmetry relegates to differences in these magnitudes. Asymmetry can be due to diffe...

  5. Protease inhibitor mediated resistance to insects

    NARCIS (Netherlands)

    Outchkourov, N.S.

    2003-01-01

    Protease inhibitors (PIs) are among the defensive molecules that plants produce in order to defend themselves against herbivores. A major aim of this thesis is to develop novel insect resistance traits usingheterologous, non-plant PIs. Prerequisite for the success of the th

  6. Mode of action of insect repellents

    Science.gov (United States)

    The mode of action of DEET and other insect repellents has been a topic of interest since the discovery of DEET in the mid twentieth century. Nearly 60 years have passed since DEET applied topically to the skin was shown to be effective in preventing mosquito bites. With the discovery and characte...

  7. Colour in the eyes of insects

    NARCIS (Netherlands)

    Stavenga, D.G.

    Many insect species have darkly coloured eyes, but distinct colours or patterns are frequently featured. A number of exemplary cases of flies and butterflies are discussed to illustrate our present knowledge of the physical basis of eye colours, their functional background, and the implications for

  8. Insects: Little Things That Run the World

    Science.gov (United States)

    Tilley, Luke

    2014-01-01

    Insects are easily the most abundant and diverse group of animals, with over 24,000 species in the UK alone. They can be found in almost every habitat on Earth and are fundamentally important to ecology, conservation, food production, animal and human health, and biodiversity. They are a prominent feature of almost every food web in the UK and…

  9. Alpha particle radiography of small insects

    Energy Technology Data Exchange (ETDEWEB)

    Chingshen Su [National Tsing Hua Univ., Hsinchu (Taiwan) Inst. of Nuclear Science

    1993-12-31

    Radiographies of ants, mosquitoes, cockroaches and small bugs have been done with a radioisotope {sup 244}Cm alpha source. Energy of alpha particles was varied by attenuating the 5.81 MeV alpha particles with adjustable air spacings from the source to the sample. The LR-115 was used to register radiographs. The image of the insect registered on the LR-115 was etched out in a 2.5 N NaOH solution at 52{sup o}C for certain minutes, depending on various irradiation conditions for the insects. For larger insects, a scanning device for the alpha particle irradiation has been fabricated to take the radiograph of whole body of the insect, and the scanning period can be selected to give desired irradiation dosage. A CCDTV camera system connected to a microscope interfaced to an IBM/AT computer is used to register the microscopic image of the radiograph and to print it out with a video copy processor. (Author).

  10. Measuring Asymmetry in Insect-Plant Networks

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Claudia P T [Programa de Pos-Graduacao em Fisica, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil); De Almeida, Adriana M [Departamento de Botanica, Ecologia e Zoologia, Centro de Biociencias, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil); Corso, Gilberto, E-mail: claudia@dfte.ufrn.br, E-mail: adrianam@ufrn.br, E-mail: corso@cb.ufrn.br [Departamento de Biofisica e Farmacologia, Centro de Biociencias, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil)

    2011-03-01

    In this work we focus on interaction networks between insects and plants and in the characterization of insect plant asymmetry, an important issue in coevolution and evolutionary biology. We analyze in particular the asymmetry in the interaction matrix of animals (herbivorous insects) and plants (food resource for the insects). Instead of driving our attention to the interaction matrix itself we derive two networks associated to the bipartite network: the animal network, D{sub 1}, and the plant network, D{sub 2}. These networks are constructed according to the following recipe: two animal species are linked once if they interact with the same plant. In a similar way, in the plant network, two plants are linked if they interact with the same animal. To explore the asymmetry between D{sub 2} and D{sub 1} we test for a set of 23 networks from the ecologic literature networks: the difference in size, {Delta}L, clustering coefficient difference, {Delta}C, and mean connectivity difference, {Delta}. We used a nonparametric statistical test to check the differences in {Delta}L, {Delta}C and {Delta}. Our results indicate that {Delta}L and {Delta} show a significative asymmetry.

  11. Coordination ability of insect kinin analogs

    Science.gov (United States)

    Spectroscopic data, including electronic absorption, CD and EPR results, as well as theoretical calculations have shown that the insertion of 4-aminopyroglutamate, a novel cis-ppetide bond mimic, in the insect kinin peptide leads to an effective ligand towards Cu(II) ions at basic pH ranges. The 4-a...

  12. Effects of carbon monoxide on insects

    Energy Technology Data Exchange (ETDEWEB)

    Baker, G.M.; Wright, E.A.

    1977-01-01

    Coccinella septempunctata (the seven-spot ladybird) and Carausis morosus (the stick insect) were exposed to low levels of CO which would not be expected to affect insects in the short term, but which might be detrimental when administered for several weeks. O/sub 2/ tension was maintained at the normal level of 20 percent. All survived when exposure was less than 10 days. 10 days or more in CO hastened death, killing 75 percent in 18 days. Only 7.7 percent of the controls died during the same period. It was observed that the ladybirds in CO were less active and consumed less food than controls. The results indicate that insects are more affected by the presence of CO in their environment than has previously been shown. Because the insects used in the experiments lacked myoglobin as well as Hb, the effects must surely have been due to the combination of CO with the respiratory enzymes. They were not due to deficiency in the supply of O/sub 2/ to the tissues. Thus availability of CO and O/sub 2/ in equal amounts has sufficient effect on the cytochrome chain to prevent growth and depress the activity of an animal. (MU)

  13. Novel proteinase inhibitor promotes resistance to insects

    Science.gov (United States)

    A novel Beta vulgaris serine proteinase inhibitor gene (BvSTI) and its protein are identified in response to insect feeding on B. vulgaris seedlings. BvSTI is cloned into an expression vector with constitutive promoter and transformed into Nicotiana benthamiana plants to assess BvSTI’s ability to ...

  14. Pathogenesis induced by (recombinant) baculoviruses in insects.

    NARCIS (Netherlands)

    Flipsen, J.Th.M.

    1995-01-01

    Infection of insect larvae by a baculovirus leads to cessation of feeding and finally to the death of the larva. Under optimal conditions this process may take as little as five days during which the virus multiplies approximately a billion times and transforms 30% of the larval weight into viral pr

  15. Pheromones in the life of insects.

    Science.gov (United States)

    Lamprecht, Ingolf; Schmolz, Erik; Schricker, Burkhard

    2008-09-01

    Life in insect societies asks for a permanent flow of information, often carried by rather simple organic molecules. Some originate from plants as odours of blossoms or exudates from trees. Especially important are the intra- and interspecific combinations of compounds produced by the insects themselves. These are called pheromones or ecto-hormones and serve a variety of tasks. The paper deals mainly with honeybee pheromones, but takes also into consideration those of wasps and hornets. Effects of pheromones are monitored ethologically by direct observation and filming as well as in a more quantitative manner with using direct and indirect calorimetry. In all experimental set-ups alarm pheromones were used as controls. They show an up to fourfold increase of activity after a few seconds, determined for small groups of insects as well as for a whole hornet nest placed in a 25-l calorimeter. A variety of cosmetics like soaps, shampoos, lotions and perfumes are included in the investigations because of repeated reports about unwarranted insect attacks which are said to be provoked by such products. None of the applied substances provoked a significant reaction of the bees (p > 0.05). A short appendix discusses the still questionable existence of pheromones in man, which were confirmed under laboratory conditions, but not yet for daily life.

  16. Pathogenesis induced by (recombinant) baculoviruses in insects

    NARCIS (Netherlands)

    Flipsen, H.

    1995-01-01

    Infection of insect larvae by a baculovirus leads to cessation of feeding and finally to the death of the larva. Under optimal conditions this process may take as little as five days during which the virus multiplies approximately a billion times and transforms 30% of the larval weight into

  17. Eco-Evolutionary Theory and Insect Outbreaks.

    Science.gov (United States)

    Páez, David J; Dukic, Vanja; Dushoff, Jonathan; Fleming-Davies, Arietta; Dwyer, Greg

    2017-06-01

    Eco-evolutionary theory argues that population cycles in consumer-resource interactions are partly driven by natural selection, such that changes in densities and changes in trait values are mutually reinforcing. Evidence that the theory explains cycles in nature, however, is almost nonexistent. Experimental tests of model assumptions are logistically impractical for most organisms, while for others, evidence that population cycles occur in nature is lacking. For insect baculoviruses in contrast, tests of model assumptions are straightforward, and there is strong evidence that baculoviruses help drive population cycles in many insects, including the gypsy moth that we study here. We therefore used field experiments with the gypsy moth baculovirus to test two key assumptions of eco-evolutionary models of host-pathogen population cycles: that reduced host infection risk is heritable and that it is costly. Our experiments confirm both assumptions, and inserting parameters estimated from our data into eco-evolutionary insect-outbreak models gives cycles closely resembling gypsy moth outbreak cycles in North America, whereas standard models predict unrealistic stable equilibria. Our work shows that eco-evolutionary models are useful for explaining outbreaks of forest insect defoliators, while widespread observations of intense selection on defoliators in nature and of heritable and costly resistance in defoliators in the lab together suggest that eco-evolutionary dynamics may play a general role in defoliator outbreaks.

  18. Natural products from microbes associated with insects

    DEFF Research Database (Denmark)

    Beemelmanns, Christine; Guo, Huijuan; Rischer, Maja;

    2016-01-01

    Here we review discoveries of secondary metabolites from microbes associated with insects. We mainly focus on natural products, where the ecological role has been at least partially elucidated, and/or the pharmaceutical properties evaluated, and on compounds with unique structural features. We...

  19. Biomimetic visual detection based on insect neurobiology

    Science.gov (United States)

    O'Carroll, David C.

    2001-11-01

    With a visual system that accounts for as much as 30% of the lifted mass, flying insects such as dragonflies and hoverflies invest more in vision than any other animal. Impressive visual performance is subserved by a surprisingly simple visual system. In a typical insect eye, between 2,000 and 30,000 pixels in the image are analyzed by fewer than 200,000 neurons in underlying neural circuits. The combination of sophisticated visual processing with an approachable level of complexity has made the insect visual system a leading model for biomimetic approaches to computer vision. Much neurobiological research has focused on neural circuits used for detection of moving patterns (e.g. optical flow during flight) and moving targets (e.g. prey). Research from several labs has led to great advances in our understanding of the neural mechanisms involved, and has spawned neuromorphic hardware based on key processes identified in neurobiological experiments. Despite its attractions, the highly non-linear nature of several key stages in insect visual processing presents a challenge to understanding. I will describe examples of adaptive elements of neural circuits in the fly visual system which analyze the direction and velocity of wide-field optical flow patterns and the result of experiments that suggest that these non-linearities may contribute to robust responses to natural image motion.

  20. Invasive pests—insects and diseases

    Science.gov (United States)

    Donald A. Duerr; Paul A. Mistretta

    2013-01-01

    Key FindingsNonnative pest species have increasing impacts in the South regardless of climate change, patterns of land ownership, or changes in the composition of vegetation.“New” nonnative invasive insects and diseases will have serious impacts on southern forests over the next 50 years. Some species such as emerald ash borer...

  1. Asexuality: the insects that stick with it.

    Science.gov (United States)

    Maderspacher, Florian

    2011-07-12

    One hope of trying to understand why sex is so powerful and prevalent a mode of reproduction relies on the rare examples of animals that persist long-term without having sex. Now, several species of stick insects join that illustrious circle.

  2. Wolbachia symbiosis and insect immune response

    Institute of Scientific and Technical Information of China (English)

    Stefanos Siozios; Panagiotis Sapountzis; Panagiotis Ioannidis; Kostas Bourtzis

    2008-01-01

    Bacterial intracellular symbiosis is very common in insects, having significant consequences in promoting the evolution of life and biodiversity. The bacterial group that has recently attracted particular attention is Wolbachia pipientis which probably represents the most ubiquitous endosymbiont on the planet. W. pipientis is a Gram-negative obligatory intracellular and maternally transmitted α-proteobacterium, that is able to establish symbiotic associations with arthropods and nematodes. In arthropods, Wolbachia pipientis infections have been described in Arachnida, in Isopoda and mainly in Insecta. They have been reported in almost all major insect orders including Diptera, Coleoptera, Hemiptera,Hymenoptera, Orthoptera and Lepidoptera. To enhance its transmission, W. pipientis can manipulate host reproduction by inducing parthenogenesis, feminization, male killing and cytoplasmic incompatibility. Several polymerase chain reaction surveys have indicated that up to 70% of all insect species may be infected with W. pipientis. How does W. pipientis manage to get established in diverse insect host species? How is this intracellular bacterial symbiont species so successful in escaping the host immune response? The present review presents recent advances and ongoing scientific efforts in the field. The current body of knowledge in the field is summarized, revelations from the available genomic information are presented and as yet unanswered questions are discussed in an attempt to present a comprehensive picture of the unique ability of W. pipientis to establish symbiosis and to manipulate reproduction while evading the host's immune system.

  3. The microRNA toolkit of insects

    Science.gov (United States)

    Ylla, Guillem; Fromm, Bastian; Piulachs, Maria-Dolors; Belles, Xavier

    2016-01-01

    Is there a correlation between miRNA diversity and levels of organismic complexity? Exhibiting extraordinary levels of morphological and developmental complexity, insects are the most diverse animal class on earth. Their evolutionary success was in particular shaped by the innovation of holometabolan metamorphosis in endopterygotes. Previously, miRNA evolution had been linked to morphological complexity, but astonishing variation in the currently available miRNA complements of insects made this link unclear. To address this issue, we sequenced the miRNA complement of the hemimetabolan Blattella germanica and reannotated that of two other hemimetabolan species, Locusta migratoria and Acyrthosiphon pisum, and of four holometabolan species, Apis mellifera, Tribolium castaneum, Bombyx mori and Drosophila melanogaster. Our analyses show that the variation of insect miRNAs is an artefact mainly resulting from poor sampling and inaccurate miRNA annotation, and that insects share a conserved microRNA toolkit of 65 families exhibiting very low variation. For example, the evolutionary shift toward a complete metamorphosis was accompanied only by the acquisition of three and the loss of one miRNA families. PMID:27883064

  4. Transgenic plants protected from insect attack

    Science.gov (United States)

    Vaeck, Mark; Reynaerts, Arlette; Höfte, Herman; Jansens, Stefan; de Beuckeleer, Marc; Dean, Caroline; Zabeau, Marc; Montagu, Marc Van; Leemans, Jan

    1987-07-01

    The Gram-positive bacterium Bacillus thuringiensis produces proteins which are specifically toxic to a variety of insect species. Modified genes have been derived from bt2, a toxin gene cloned from one Bacillus strain. Transgenic tobacco plants expressing these genes synthesize insecticidal proteins which protect them from feeding damage by larvae of the tobacco hornworm.

  5. Plant defences against herbivore and insect attack

    Science.gov (United States)

    Plants deploy a number of defences against attack by insects and other herbivores. Direct defence is conferred by plant products and structures that deter or kill the herbivores. Chemical toxins and deterrents vary widely among plant species, and some typical toxins include alkaloids, terpenoids, st...

  6. Riparian forestry management and adult stream insects

    Directory of Open Access Journals (Sweden)

    R. A. Briers

    2004-01-01

    Full Text Available The impacts of coniferous plantation forestry on the biology of upland streams in the UK are firmly established. Whilst benthic communities have been well studied, very little research has considered the impacts of riparian forestry management on adult stream insects, yet the essentially terrestrial adult (reproductive phase may be important in determining the abundance and distribution of larval stages. Riparian vegetation has a potentially strong impact on survival and success of adult stages through alteration of microclimate, habitat structure and potential food sources, in addition to effects carried over from larval stages. Here, current riparian management strategies are analysed in the light of available information on the ecology of adult stream insects. On the whole, management practices appear to favour adult stream insects, although an increase in tree cover in riparian areas could be beneficial, by providing more favourable microclimatic conditions for adults. This conclusion is drawn based on rather limited information, and the need for further research into the effects of riparian forestry management on adult stream insects is highlighted. Keywords: microclimate, plantation, life history, riparian vegetation

  7. Insects of war, terror and torture

    Science.gov (United States)

    From plagues to malaria transmission, insects and other arthropods have been natural or intentional health and agricultural threats to military and civilian populations throughout human history. The success or failure of military operations frequently has been determined by correctly anticipating in...

  8. Insect photoreceptor adaptations to night vision.

    Science.gov (United States)

    Honkanen, Anna; Immonen, Esa-Ville; Salmela, Iikka; Heimonen, Kyösti; Weckström, Matti

    2017-04-05

    Night vision is ultimately about extracting information from a noisy visual input. Several species of nocturnal insects exhibit complex visually guided behaviour in conditions where most animals are practically blind. The compound eyes of nocturnal insects produce strong responses to single photons and process them into meaningful neural signals, which are amplified by specialized neuroanatomical structures. While a lot is known about the light responses and the anatomical structures that promote pooling of responses to increase sensitivity, there is still a dearth of knowledge on the physiology of night vision. Retinal photoreceptors form the first bottleneck for the transfer of visual information. In this review, we cover the basics of what is known about physiological adaptations of insect photoreceptors for low-light vision. We will also discuss major enigmas of some of the functional properties of nocturnal photoreceptors, and describe recent advances in methodologies that may help to solve them and broaden the field of insect vision research to new model animals.This article is part of the themed issue 'Vision in dim light'.

  9. Colour in the eyes of insects

    NARCIS (Netherlands)

    Stavenga, D.G.

    2002-01-01

    Many insect species have darkly coloured eyes, but distinct colours or patterns are frequently featured. A number of exemplary cases of flies and butterflies are discussed to illustrate our present knowledge of the physical basis of eye colours, their functional background, and the implications for

  10. A new family of insect tyramine receptors

    DEFF Research Database (Denmark)

    Cazzamali, Giuseppe; Klærke, Dan Arne; Grimmelikhuijzen, Cornelis J P

    2005-01-01

    in the genomic databases from the malaria mosquito Anopheles gambiae and the honeybee Apis mellifera. These four tyramine or tyramine-like receptors constitute a new receptor family that is phylogenetically distinct from the previously identified insect octopamine/tyramine receptors. The Drosophila tyramine...

  11. Democratizing evolutionary biology, lessons from insects

    DEFF Research Database (Denmark)

    Dunn, Robert Roberdeau; Beasley, DeAnna E.

    2016-01-01

    The engagement of the public in the scientific process is an old practice. Yet with recent advances in technology, the role of the citizen scientist in studying evolutionary processes has increased. Insects provide ideal models for understanding these evolutionary processes at large scales...

  12. Insect overwintering in a changing climate.

    Science.gov (United States)

    Bale, J S; Hayward, S A L

    2010-03-15

    Insects are highly successful animals inhabiting marine, freshwater and terrestrial habitats from the equator to the poles. As a group, insects have limited ability to regulate their body temperature and have thus required a range of strategies to support life in thermally stressful environments, including behavioural avoidance through migration and seasonal changes in cold tolerance. With respect to overwintering strategies, insects have traditionally been divided into two main groups: freeze tolerant and freeze avoiding, although this simple classification is underpinned by a complex of interacting processes, i.e. synthesis of ice nucleating agents, cryoprotectants, antifreeze proteins and changes in membrane lipid composition. Also, in temperate and colder climates, the overwintering ability of many species is closely linked to the diapause state, which often increases cold tolerance ahead of temperature-induced seasonal acclimatisation. Importantly, even though most species can invoke one or both of these responses, the majority of insects die from the effects of cold rather than freezing. Most studies on the effects of a changing climate on insects have focused on processes that occur predominantly in summer (development, reproduction) and on changes in distributions rather than winter survival per se. For species that routinely experience cold stress, a general hypothesis would be that predicted temperature increases of 1 degree C to 5 degrees C over the next 50-100 years would increase winter survival in some climatic zones. However, this is unlikely to be a universal effect. Negative impacts may occur if climate warming leads to a reduction or loss of winter snow cover in polar and sub-polar areas, resulting in exposure to more severe air temperatures, increasing frequency of freeze-thaw cycles and risks of ice encasement. Likewise, whilst the dominant diapause-inducing cue (photoperiod) will be unaffected by global climate change, higher temperatures may

  13. Recombinant Protein Production and Insect Cell Culture and Process

    Science.gov (United States)

    Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); OConnor, Kim C. (Inventor); Francis, Karen M. (Inventor); Andrews, Angela D. (Inventor); Prewett, Tracey L. (Inventor)

    1997-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using virtually infected or stably transformed insect cells containing a gene encoding the described polypeptide. The insect cells can also be a host for viral production.

  14. Entomopathogenic Nematodes for the Biological Control of Pest Insects

    OpenAIRE

    Ljerka Oštrec

    2001-01-01

    Entomopathogenic nematodes are part of 9 families, but only some species of these families: Heterorhabditidae, Mermithidae and Steinernematidae kill insects. Infective juveniles enter the insect host through the cuticle, or through the mouth, anus, etc., to reach the haemocel. The infective juveniles also enter the insect by the foot. After that the nematodes leave the insect who usually dies. The infective juveniles are associated with symbiotic bacterium (Xenorhabdus, Photorhabdus) which h...

  15. Entomopathogenic Nematodes for the Biological Control of Pest Insects

    OpenAIRE

    Ljerka Oštrec

    2001-01-01

    Entomopathogenic nematodes are part of 9 families, but only some species of these families: Heterorhabditidae, Mermithidae and Steinernematidae kill insects. Infective juveniles enter the insect host through the cuticle, or through the mouth, anus, etc., to reach the haemocel. The infective juveniles also enter the insect by the foot. After that the nematodes leave the insect who usually dies. The infective juveniles are associated with symbiotic bacterium (Xenorhabdus, Photorhabdus) which h...

  16. Similarities between decapod and insect neuropeptidomes.

    Science.gov (United States)

    Veenstra, Jan A

    2016-01-01

    Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone), a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for decapod neuropeptides

  17. Similarities between decapod and insect neuropeptidomes

    Directory of Open Access Journals (Sweden)

    Jan A. Veenstra

    2016-05-01

    Full Text Available Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone, a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for

  18. Similarities between decapod and insect neuropeptidomes

    Science.gov (United States)

    2016-01-01

    Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone), a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for decapod neuropeptides

  19. Evolution of DNA Methylation across Insects.

    Science.gov (United States)

    Bewick, Adam J; Vogel, Kevin J; Moore, Allen J; Schmitz, Robert J

    2017-03-01

    DNA methylation contributes to gene and transcriptional regulation in eukaryotes, and therefore has been hypothesized to facilitate the evolution of plastic traits such as sociality in insects. However, DNA methylation is sparsely studied in insects. Therefore, we documented patterns of DNA methylation across a wide diversity of insects. We predicted that underlying enzymatic machinery is concordant with patterns of DNA methylation. Finally, given the suggestion that DNA methylation facilitated social evolution in Hymenoptera, we tested the hypothesis that the DNA methylation system will be associated with presence/absence of sociality among other insect orders. We found DNA methylation to be widespread, detected in all orders examined except Diptera (flies). Whole genome bisulfite sequencing showed that orders differed in levels of DNA methylation. Hymenopteran (ants, bees, wasps and sawflies) had some of the lowest levels, including several potential losses. Blattodea (cockroaches and termites) show all possible patterns, including a potential loss of DNA methylation in a eusocial species whereas solitary species had the highest levels. Species with DNA methylation do not always possess the typical enzymatic machinery. We identified a gene duplication event in the maintenance DNA methyltransferase 1 (DNMT1) that is shared by some Hymenoptera, and paralogs have experienced divergent, nonneutral evolution. This diversity and nonneutral evolution of underlying machinery suggests alternative DNA methylation pathways may exist. Phylogenetically corrected comparisons revealed no evidence that supports evolutionary association between sociality and DNA methylation. Future functional studies will be required to advance our understanding of DNA methylation in insects. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  20. Evaluation of hazardous chemicals in edible insects and insect-based food intended for human consumption.

    Science.gov (United States)

    Poma, Giulia; Cuykx, Matthias; Amato, Elvio; Calaprice, Chiara; Focant, Jean Francois; Covaci, Adrian

    2017-02-01

    Due to the rapid increase in world population, the waste of food and resources, and non-sustainable food production practices, the use of alternative food sources is currently strongly promoted. In this perspective, insects may represent a valuable alternative to main animal food sources due to their nutritional value and sustainable production. However, edible insects may be perceived as an unappealing food source and are indeed rarely consumed in developed countries. The food safety of edible insects can thus contribute to the process of acceptance of insects as an alternative food source, changing the perception of developed countries regarding entomophagy. In the present study, the levels of organic contaminants (i.e. flame retardants, PCBs, DDT, dioxin compounds, pesticides) and metals (As, Cd, Co, Cr, Cu, Ni, Pb, Sn, Zn) were investigated in composite samples of several species of edible insects (greater wax moth, migratory locust, mealworm beetle, buffalo worm) and four insect-based food items currently commercialized in Belgium. The organic chemical mass fractions were relatively low (PCBs: 27-2065 pg/g ww; OCPs: 46-368 pg/g ww; BFRs: up to 36 pg/g ww; PFRs 783-23800 pg/g ww; dioxin compounds: up to 0.25 pg WHO-TEQ/g ww) and were generally lower than those measured in common animal products. The untargeted screening analysis revealed the presence of vinyltoluene, tributylphosphate (present in 75% of the samples), and pirimiphos-methyl (identified in 50% of the samples). The levels of Cu and Zn in insects were similar to those measured in meat and fish in other studies, whereas As, Co, Cr, Pb, Sn levels were relatively low in all samples (insect species with no additional hazards in comparison to the more commonly consumed animal products. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Quantifying the Movement of Multiple Insects Using an Optical Insect Counter

    Science.gov (United States)

    2010-06-01

    insects crossed, with respect to the tunnel width. To test the OIC imaging system, 20 mosquitoes (5–15 day-old female Aedes aegypti L.) contained in a 20...Douglas LW. 1986. Female sex pheromone of the melonworm, Diaphania hylinata (Lepidoptera: Pyralidae) and analysis of male responses to pheromone in a...moving upwind in the tunnel. The time differential between the 2 triggering events can also be used to calculate velocity if individual insects passing

  2. 25 CFR 163.31 - Insect and disease control.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  3. 46 CFR 92.20-55 - Insect screens.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Insect screens. 92.20-55 Section 92.20-55 Shipping COAST... ARRANGEMENT Accommodations for Officers and Crew § 92.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  4. Metabolomics reveals insect metabolic responses associated with fungal infection.

    Science.gov (United States)

    Xu, Yong-Jiang; Luo, Feifei; Gao, Qiang; Shang, Yanfang; Wang, Chengshu

    2015-06-01

    The interactions between insects and pathogenic fungi are complex. We employed metabolomic techniques to profile insect metabolic dynamics upon infection by the pathogenic fungus Beauveria bassiana. Silkworm larvae were infected with fungal spores and microscopic observations demonstrated that the exhaustion of insect hemocytes was coupled with fungal propagation in the insect body cavity. Metabolomic analyses revealed that fungal infection could significantly alter insect energy and nutrient metabolisms as well as the immune defense responses, including the upregulation of carbohydrates, amino acids, fatty acids, and lipids, but the downregulation of eicosanoids and amines. The insect antifeedant effect of the fungal infection was evident with the reduced level of maclurin (a component of mulberry leaves) in infected insects but elevated accumulations in control insects. Insecticidal and cytotoxic mycotoxins like oosporein and beauveriolides were also detected in insects at the later stages of infection. Taken together, the metabolomics data suggest that insect immune responses are energy-cost reactions and the strategies of nutrient deprivation, inhibition of host immune responses, and toxin production would be jointly employed by the fungus to kill insects. The data obtained in this study will facilitate future functional studies of genes and pathways associated with insect-fungus interactions.

  5. 46 CFR 190.20-55 - Insect screens.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Insect screens. 190.20-55 Section 190.20-55 Shipping... ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  6. 46 CFR 72.20-55 - Insect screens.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Insect screens. 72.20-55 Section 72.20-55 Shipping COAST... Accommodations for Officers and Crew § 72.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  7. Diseases in insects produced for food and feed

    NARCIS (Netherlands)

    Eilenberg, J.; Vlak, J.M.; Nielsen-LeRoux, C.; Capellozza, S.; Jensen, A.B.

    2015-01-01

    Increased production of insects on a large scale for food and feed will likely lead to many novel challenges, including problems with diseases. We provide an overview of important groups of insect pathogens, which can cause disease in insects produced for food and feed. Main characteristics of each

  8. The insect cookbook : food for a sustainable planet

    NARCIS (Netherlands)

    Huis, van A.; Gurp, van H.; Dicke, M.

    2014-01-01

    In The Insect Cookbook, two entomologists and a chef make the case for insects as a sustainable source of protein for humans and a necessary part of our future diet. They provide consumers and chefs with the essential facts about insects for culinary use, with recipes simple enough to make at home y

  9. Diseases in insects produced for food and feed

    NARCIS (Netherlands)

    Eilenberg, J.; Vlak, J.M.; Nielsen-LeRoux, C.; Capellozza, S.; Jensen, A.B.

    2015-01-01

    Increased production of insects on a large scale for food and feed will likely lead to many novel challenges, including problems with diseases. We provide an overview of important groups of insect pathogens, which can cause disease in insects produced for food and feed. Main characteristics of each

  10. Coconut leaf bioactivity toward generalist maize insect pests

    Science.gov (United States)

    Tropical plants are often more resistant to insects than temperate plants due to evolution of robust defenses to cope with a more constant insect threat. Coconut (Cocos nucifera L.) has very few chewing leaf feeding insect pests and was tested against two omnivorous leaf feeding caterpillar species,...

  11. Viruses of insects reared for food and feed

    NARCIS (Netherlands)

    Maciel-Vergara, Gabriela; Ros, Vera I.D.

    2017-01-01

    The use of insects as food for humans or as feed for animals is an alternative for the increasing high demand for meat and has various environmental and social advantages over the traditional intensive production of livestock. Mass rearing of insects, under insect farming conditions or even in in

  12. An extreme case of plant-insect codiversification

    DEFF Research Database (Denmark)

    Cruaud, Astrid; Rønsted, Nina; Chanterasuwan, Bhanumas;

    2012-01-01

    It is thought that speciation in phytophagous insects is often due to colonization of novel host plants, because radiations of plant and insect lineages are typically asynchronous. Recent phylogenetic comparisons have supported this model of diversification for both insect herbivores and speciali...

  13. Forest Insect and Disease Tally System (FINDIT) user manual

    Science.gov (United States)

    Barbara J. Bentz

    2000-01-01

    FINDIT, the Forest Insect and Disease Tally System, is an easy-to-use tool for analyzing insect and disease population information taken during stand surveys. Incidence of insects, pathogens, and other biotic and abiotic influences on forest ecosystems are summarized using traditional mensurational measurements. Information is summarized by diameter class, tree species...

  14. 7 CFR 58.147 - Insect and rodent control program.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Insect and rodent control program. 58.147 Section 58... Service 1 Operations and Operating Procedures § 58.147 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control...

  15. 7 CFR 58.247 - Insect and rodent control program.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Insect and rodent control program. 58.247 Section 58... Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control program...

  16. 20 CFR 654.415 - Insect and rodent control.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Insect and rodent control. 654.415 Section 654.415 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR SPECIAL... Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other vermin....

  17. Evolution of holometabola insect digestive systems: physiological and biochemical aspects

    Directory of Open Access Journals (Sweden)

    Walter R. Terra

    1987-01-01

    Full Text Available This review takes into account primarily the work done in our laboratory with insects from the major Holometabola orders. Only the most significant data for each insect will be presented and a proposal on the evolution of Holometabola insect digstive systems will be advanced.

  18. Physical principles of fluid-mediated insect attachment - Shouldn't insects slip?

    Science.gov (United States)

    Dirks, Jan-Henning

    2014-01-01

    Insects use either hairy or smooth adhesive pads to safely adhere to various kinds of surfaces. Although the two types of adhesive pads are morphologically different, they both form contact with the substrate via a thin layer of adhesive fluid. To model adhesion and friction forces generated by insect footpads often a simple "wet adhesion" model is used, in which two flat undeformable substrates are separated by a continuous layer of fluid. This review summarizes the key physical and tribological principles that determine the adhesion and friction in such a model. Interestingly, such a simple wet-adhesion model falls short in explaining several features of insect adhesion. For example, it cannot predict the observed high static friction forces of the insects, which enable them to cling to vertical smooth substrates without sliding. When taking a closer look at the "classic" attachment model, one can see that it is based on several simplifications, such as rigid surfaces or continuous layers of Newtonian fluids. Recent experiments show that these assumptions are not valid in many cases of insect adhesion. Future tribological models for insect adhesion thus need to incorporate deformable adhesive pads, non-Newtonian properties of the adhesive fluid and/or partially "dry" or solid-like contact between the pad and the substrate.

  19. 5种植物源杀虫剂防治烟蚜效果研究%Field Trials of 5 Kinds of Botanical Insecticides against Myzus persicae(Sulzer)

    Institute of Scientific and Technical Information of China (English)

    罗会斌; 李忠俊; 杨洪

    2012-01-01

    In this paper,five botanical insecticides(3% matrine AS,0.2% Celastrus angulatus EC,0.3% neem EC,0.5% veratridine SLX,and 4% rotenone EC) were conducted against Myzus persicae(Sulzer) on tobacco through field trails.The results showed that 3% matrine AS and 0.2% Celastrus angulatus EC had significant effects on M.persicae with the control efficacy over 90% at 20 days after the treatment.The two botanical insecticides were recommended against M.persicae on tobacco in nonpollution or organic fields.%选用5种不同的植物源杀虫剂3%苦参碱水剂,0.2%苦皮藤素乳油,0.3%印楝素乳油,0.5%藜芦碱可溶性液剂,4%鱼藤酮乳油对烟蚜进行田间防治试验。结果表明,3%苦参碱水剂和0.2%苦皮藤素乳油对烟蚜防效皆达到90%以上,药效期可持续20 d。因此,3%苦参碱水剂和0.2%苦皮藤素乳油这两种植物源杀虫剂可作为无公害烟叶和有机烟叶生产中防治烟蚜的推荐药剂。

  20. Photorhabdus luminescens genes induced upon insect infection

    Directory of Open Access Journals (Sweden)

    Jung Kirsten

    2008-05-01

    Full Text Available Abstract Background Photorhabdus luminescens is a Gram-negative luminescent enterobacterium and a symbiote to soil nematodes belonging to the species Heterorhabditis bacteriophora. P.luminescens is simultaneously highly pathogenic to insects. This bacterium exhibits a complex life cycle, including one symbiotic stage characterized by colonization of the upper nematode gut, and a pathogenic stage, characterized by release from the nematode into the hemocoel of insect larvae, resulting in rapid insect death caused by bacterial toxins. P. luminescens appears to sense and adapt to the novel host environment upon changing hosts, which facilitates the production of factors involved in survival within the host, host-killing, and -exploitation. Results A differential fluorescence induction (DFI approach was applied to identify genes that are up-regulated in the bacterium after infection of the insect host Galleria mellonella. For this purpose, a P. luminescens promoter-trap library utilizing the mCherry fluorophore as a reporter was constructed, and approximately 13,000 clones were screened for fluorescence induction in the presence of a G. mellonella larvae homogenate. Since P. luminescens has a variety of regulators that potentially sense chemical molecules, like hormones, the screen for up-regulated genes or operons was performed in vitro, excluding physicochemical signals like oxygen, temperature or osmolarity as variables. Clones (18 were obtained exhibiting at least 2.5-fold induced fluorescence and regarded as specific responders to insect homogenate. In combination with a bioinformatics approach, sequence motifs were identified in these DNA-fragments that are similar to 29 different promoters within the P. luminescens genome. By cloning each of the predicted promoters upstream of the reporter gene, induction was verified for 27 promoters in vitro, and for 24 promoters in viable G. mellonella larvae. Among the validated promoters are some known

  1. Spectral composition of light sources and insect phototaxis, with an evaluation of existing spectral response models. Journal of Insect Conservation

    NARCIS (Netherlands)

    Grunsven, van R.H.A.; Donners, M.; Boekee, K.; Tichelaar, I.; Geffen, van K.G.; Groenendijk, D.; Berendse, F.; Veenendaal, E.M.

    2014-01-01

    Artificial illumination attracts insects, but to what extent light attracts insects, depends on the spectral composition of the light. Response models have been developed to predict the attractiveness of artificial light sources. In this study we compared attraction of insects by existing light sour

  2. External Insect Morphology: A Negative Factor in Attitudes toward Insects and Likelihood of Incorporation in Future Science Education Settings

    Science.gov (United States)

    Wagler, Ron; Wagler, Amy

    2012-01-01

    This study investigated if the external morphology of an insect had a negative effect on United States (US) preservice elementary teacher's attitudes toward insects and beliefs concerning the likelihood of incorporating insects into future science education settings. 270 US kindergarten through sixth grade preservice elementary teachers…

  3. Multi-factor climate change effects on insect herbivore performance

    DEFF Research Database (Denmark)

    Scherber, Christoph; Gladbach, David J; Stevnbak, Karen;

    2013-01-01

    The impact of climate change on herbivorous insects can have far-reaching consequences for ecosystem processes. However, experiments investigating the combined effects of multiple climate change drivers on herbivorous insects are scarce. We independently manipulated three climate change drivers (CO......, and water content. Overall, drought was the most important factor for this insect herbivore. Our study shows that weight and survival of insect herbivores may decline under future climate. The complexity of insect herbivore responses increases with the number of combined climate change drivers....

  4. Viruses of insects reared for food and feed

    DEFF Research Database (Denmark)

    Maciel Vergara, Gabriela; Ros, Vera I.D.

    2017-01-01

    The use of insects as food for humans or as feed for animals is an alternative for the increasing high demand for meat and has various environmental and social advantages over the traditional intensive production of livestock. Mass rearing of insects, under insect farming conditions or even...... for the productivity and the quality of mass rearing systems. Prevention and management of viral diseases imply the understanding of the different factors that interact in insect mass rearing. This publication provides an overview of the known viruses in insects most commonly reared for food and feed. Nowadays...

  5. [Synergism of plant volatiles to insect pheromones and related mechanisms].

    Science.gov (United States)

    Wang, Zhen-hua; Zhao, Hui; Li, Jin-fu; Zeng, Xian-dong; Chen, Jian-jun; Feng, Han-li; Xu, Jia-wen

    2008-11-01

    Host plant volatiles and insect pheromones are the most important semiochemicals for insects, and their synergism can modulate insect behaviors. The attraction to sex- and aggregation pheromones of insects can be greatly enhanced by specific plant volatiles through the increased electroantennogram, pheromone incepting neuron action potential, and pulse-frequency. When the specific plant volatiles are bound with octopamine receptors, the threshold of sex pheromone incepting neuron to sex pheromones is decreased, while the sensibility of sex pheromone incepting neuron is increased, which may be the main mechanism for the synergism of plant volatiles to insect pheromones.

  6. Social insects: from selfish genes to self organisation and beyond

    DEFF Research Database (Denmark)

    Boomsma, Jacobus Jan; Franks, Nigel R.

    2006-01-01

    Selfish gene and self-organisation approaches have revolutionised the study of social insects and have provided unparalleled insights into the highly sophisticated nature of insect social evolution. Here, we briefly review the core programs and interfaces with communication and recognition studie...... that characterise these fields today, and offer an interdisciplinary future perspective for the study of social insect evolutionary biology.......Selfish gene and self-organisation approaches have revolutionised the study of social insects and have provided unparalleled insights into the highly sophisticated nature of insect social evolution. Here, we briefly review the core programs and interfaces with communication and recognition studies...

  7. RNAi for insect control: current perspective and future challenges.

    Science.gov (United States)

    Katoch, Rajan; Sethi, Amit; Thakur, Neelam; Murdock, Larry L

    2013-10-01

    The research on the RNA interference (RNAi) for the control of insect pests has made significant growth in recent years. The availability of the genomic sequences of insects has further widened the horizons for the testing of this technology to various insect groups. Different modes of application of double-stranded RNA (dsRNA) have been tested; however, the practicability of delivery of dsRNA in insects still remains the biggest challenge. Till date, the oral delivery of dsRNA in insects is one of the efficient approaches for the practical application of this technique. The uptake of dsRNA from the insect gut is mediated either by SID-1/SID-2 transmembrane proteins or by endocytosis; however, the systemic RNAi machinery still remains to be revealed in insect species. The RNAi-mediated gene knockdown has shown striking results in different insect groups, pointing it to be the upcoming technique for insect control. However, before the successful application of this technique for insect control, some potential issues need to be resolved. This review presents the account of prospects and challenges for the use of this technology for insect control.

  8. Exploiting natural variation to identify insect-resistance genes.

    Science.gov (United States)

    Broekgaarden, Colette; Snoeren, Tjeerd A L; Dicke, Marcel; Vosman, Ben

    2011-10-01

    Herbivorous insects are widespread and often serious constraints to crop production. The use of insect-resistant crops is a very effective way to control insect pests in agriculture, and the development of such crops can be greatly enhanced by knowledge on plant resistance mechanisms and the genes involved. Plants have evolved diverse ways to cope with insect attack that has resulted in natural variation for resistance towards herbivorous insects. Studying the molecular genetics and transcriptional background of this variation has facilitated the identification of resistance genes and processes that lead to resistance against insects. With the development of new technologies, molecular studies are not restricted to model plants anymore. This review addresses the need to exploit natural variation in resistance towards insects to increase our knowledge on resistance mechanisms and the genes involved. We will discuss how this knowledge can be exploited in breeding programmes to provide sustainable crop protection against insect pests. Additionally, we discuss the current status of genetic research on insect-resistance genes. We conclude that insect-resistance mechanisms are still unclear at the molecular level and that exploiting natural variation with novel technologies will contribute greatly to the development of insect-resistant crop varieties.

  9. Emerging strategies for RNA interference (RNAi) applications in insects.

    Science.gov (United States)

    Nandety, Raja Sekhar; Kuo, Yen-Wen; Nouri, Shahideh; Falk, Bryce W

    2015-01-01

    RNA interference (RNAi) in insects is a gene regulatory process that also plays a vital role in the maintenance and in the regulation of host defenses against invading viruses. Small RNAs determine the specificity of the RNAi through precise recognition of their targets. These small RNAs in insects comprise small interfering RNAs (siRNAs), micro RNAs (miRNAs) and Piwi interacting RNAs (piRNAs) of various lengths. In this review, we have explored different forms of the RNAi inducers that are presently in use, and their applications for an effective and efficient fundamental and practical RNAi research with insects. Further, we reviewed trends in next generation sequencing (NGS) technologies and their importance for insect RNAi, including the identification of novel insect targets as well as insect viruses. Here we also describe a rapidly emerging trend of using plant viruses to deliver the RNAi inducer molecules into insects for an efficient RNAi response.

  10. Insect phylogenetics in the digital age.

    Science.gov (United States)

    Dietrich, Christopher H; Dmitriev, Dmitry A

    2016-12-01

    Insect systematists have long used digital data management tools to facilitate phylogenetic research. Web-based platforms developed over the past several years support creation of comprehensive, openly accessible data repositories and analytical tools that support large-scale collaboration, accelerating efforts to document Earth's biota and reconstruct the Tree of Life. New digital tools have the potential to further enhance insect phylogenetics by providing efficient workflows for capturing and analyzing phylogenetically relevant data. Recent initiatives streamline various steps in phylogenetic studies and provide community access to supercomputing resources. In the near future, automated, web-based systems will enable researchers to complete a phylogenetic study from start to finish using resources linked together within a single portal and incorporate results into a global synthesis.

  11. Insects are Crawling in My Genital Warts.

    Science.gov (United States)

    Dhawan, Jyoti; Singh, Saurabh; Gupta, Somesh

    2011-05-01

    A 23-year-old woman presented with large exophytic genital wart arising from perineum, vulva, introitus of the vagina, and inner aspect of thighs. Patient developed severe itching and formication (insect-crawling sensation) in the lesions for past 1 week, though careful examination did not reveal any insects. Considering that the disease was causing psychological stress and physical symptoms, radiofrequency excision was planned. However, during the procedure, several maggots appeared from the crypts. The procedure was abandoned and maggots were removed manually. Subsequently external giant warts were removed using radiofrequency device. There was no recurrence of excised warts during 3 month follow-up. To our knowledge, this is the second reported case of maggots in genital warts.

  12. Insects are crawling in my genital warts

    Directory of Open Access Journals (Sweden)

    Jyoti Dhawan

    2011-01-01

    Full Text Available A 23-year-old woman presented with large exophytic genital wart arising from perineum, vulva, introitus of the vagina, and inner aspect of thighs. Patient developed severe itching and formication (insect-crawling sensation in the lesions for past 1 week, though careful examination did not reveal any insects. Considering that the disease was causing psychological stress and physical symptoms, radiofrequency excision was planned. However, during the procedure, several maggots appeared from the crypts. The procedure was abandoned and maggots were removed manually. Subsequently external giant warts were removed using radiofrequency device. There was no recurrence of excised warts during 3 month follow-up. To our knowledge, this is the second reported case of maggots in genital warts.

  13. Culture and manipulation of insect facultative symbionts.

    Science.gov (United States)

    Pontes, Mauricio H; Dale, Colin

    2006-09-01

    Insects from many different taxonomic groups harbor maternally transmitted bacterial symbionts. Some of these associations are ancient in origin and obligate in nature whereas others originated more recently and are facultative. Previous research focused on the biology of ancient obligate symbionts with essential nutritional roles in their insect hosts. However, recent important advances in understanding the biology of facultative associations have been driven by the development of techniques for the culture, genetic modification and manipulation of facultative symbionts. In this review, we examine these available experimental techniques and illustrate how they have provided fascinating new insight into the nature of associations involving facultative symbionts. We also propose a rationale for future research based on the integration of genomics and experimentation.

  14. Specialized Pathogen of a Social Insect

    DEFF Research Database (Denmark)

    Małagocka, Joanna

    . The pattern of cadaver distribution is associated with ant density, i.e. fungus killed cadavers stay close to the nest and foraging trails. This indicates that manipulation is adaptive for the fungus, and that social exclusion of sick individuals, which has previously been reported in social insects, does......, on the other hand, are remarkably efficient at preventing disease, a trait which necessarily arose together with social organization. In the one known example of social insects, in this case wood ants of the genus Formica, being attacked by an entomophthoralean fungus – Pandora formicae, social behaviors...... provide a game changing component that shapes the interaction in quite a unique way. This thesis explores some of the aspects of biology of host-pathogen interaction between red wood ants, F. polyctena, and the fungus P. formicae. First, the taxonomy of the fungus is studied and some nomenclatural issues...

  15. Insects as vectors: systematics and biology.

    Science.gov (United States)

    Rodhain, F

    2015-04-01

    Among the many complex relationships between insects and microorganisms such as viruses, bacteria and parasites, some have resulted in the establishment of biological systems within which the insects act as a biological vector for infectious agents. It is therefore advisable to understand the identity and biology of these vectors in depth, in order to define procedures for epidemiological surveillance and anti-vector control. The following are successively reviewed in this article: Anoplura (lice), Siphonaptera (fleas), Heteroptera (bugs: Cimicidae, Triatoma, Belostomatidae), Psychodidae (sandflies), Simuliidae (black flies), Ceratopogonidae (biting midges), Culicidae (mosquitoes), Tabanidae (horseflies) and Muscidae (tsetse flies, stable flies and pupipara). The authors provide a rapid overview of the morphology, systematics, development cycle and bio-ecology of each of these groups of vectors. Finally, their medical and veterinary importance is briefly reviewed.

  16. Management of insect pests using semiochemical traps

    DEFF Research Database (Denmark)

    Baroffio, C. A.; Guibert, V.; Richoz, P.

    2016-01-01

    In the absence of effective control measures, the strawberry blossom weevil (Anthonomus rubi) (SBW) and the raspberry beetle (Byturus tomentosus) (RB) cause large (10 - >80%) losses in yield and quality in organically grown raspberry. Attractive lures for both pests were combined into a single...... multitrap for the economical management of both of these pests at the same time. This is one of the first approaches to pest management of non-lepidopteran insect pests of horticultural crops using semiochemicals in the EU, and probably the first to target multiple species from different insect orders....... The aim is to develop optimized lures and cost-effective trap designs for mass trapping and to determine the optimum density and spatial and temporal patterns of deployment of the traps for controlling these pests by mass trapping. The combination between an aggregation pheromone that attracts Anthonomus...

  17. Climate Change Effects Overwintering of Insects

    DEFF Research Database (Denmark)

    Vukasinovic, Dragana

    Climate change is modifying winter conditions rapidly and predicting species’ reactions to global warming has been the “the holy grail” of climate sciences, especially for managed systems, like agro-ecosystems. Intuitively, increased winter temperatures should release insects from coldinduced......) and could affect post-winter reproduction. In the case of D. radicum, mild winter caused earlier emergence of flies.Overall, this study showed that mild winters increased mortality of H. axyridis, but earlier onset of population growth may compensate for this, and in D. radicum mild winters decreased...... mortality and induced earli er emergence of flies. Thus, for some species, like H. axyridis, mild winters may not benefit nor conclusively stress the species, but for others like D. radicum, mild winters may benefit the population and be of concern to farmers.Agricultural insect fauna is a prime example...

  18. Specialized Pathogen of a Social Insect

    DEFF Research Database (Denmark)

    Małagocka, Joanna

    , on the other hand, are remarkably efficient at preventing disease, a trait which necessarily arose together with social organization. In the one known example of social insects, in this case wood ants of the genus Formica, being attacked by an entomophthoralean fungus – Pandora formicae, social behaviors...... provide a game changing component that shapes the interaction in quite a unique way. This thesis explores some of the aspects of biology of host-pathogen interaction between red wood ants, F. polyctena, and the fungus P. formicae. First, the taxonomy of the fungus is studied and some nomenclatural issues...... in the context of social immunity and response to disease. Ants normally remove dead nestmates and all other insects from their environment as prophylactic hygienic measure, and to use as protein source. I used behavioral choice experiments to assess whether persistent removal of Pandora-killed cadavers...

  19. Remote radio control of insect flight.

    Science.gov (United States)

    Sato, Hirotaka; Berry, Christopher W; Peeri, Yoav; Baghoomian, Emen; Casey, Brendan E; Lavella, Gabriel; Vandenbrooks, John M; Harrison, Jon F; Maharbiz, Michel M

    2009-01-01

    We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

  20. Remote radio control of insect flight

    Directory of Open Access Journals (Sweden)

    Hirotaka Sato

    2009-10-01

    Full Text Available We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely-controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

  1. Interactions between parasites and insects vectors

    Directory of Open Access Journals (Sweden)

    Hilary Hurd

    1994-01-01

    Full Text Available This review stresses the importance of studies that will provide a basic understanding of the pathology of parasite-infected vector insects. This knowledge should be a vital component of the very focussed initiatives currently being funded in the areas of vector control. Vector fecundity reduction is discussed as an example of such pathology. Underlying mechanisms are being investigated in a model system, Hymenolepis diminuta-infected Tenebrio molitor and in Onchocerca-infected blackflies and Plasmodium-infected Anopheles stephensi. In all cases, host vitellogenesis is disrupted by the parasite and, in the tapeworm/beetle model, interaction between the parasite and the endocrine control of the insect's reproductive physiology has been demonstrated.

  2. Vision and visual navigation in nocturnal insects.

    Science.gov (United States)

    Warrant, Eric; Dacke, Marie

    2011-01-01

    With their highly sensitive visual systems, nocturnal insects have evolved a remarkable capacity to discriminate colors, orient themselves using faint celestial cues, fly unimpeded through a complicated habitat, and navigate to and from a nest using learned visual landmarks. Even though the compound eyes of nocturnal insects are significantly more sensitive to light than those of their closely related diurnal relatives, their photoreceptors absorb photons at very low rates in dim light, even during demanding nocturnal visual tasks. To explain this apparent paradox, it is hypothesized that the necessary bridge between retinal signaling and visual behavior is a neural strategy of spatial and temporal summation at a higher level in the visual system. Exactly where in the visual system this summation takes place, and the nature of the neural circuitry that is involved, is currently unknown but provides a promising avenue for future research.

  3. Oxygen reperfusion damage in an insect.

    Directory of Open Access Journals (Sweden)

    John R B Lighton

    Full Text Available The deleterious effects of anoxia followed by reperfusion with oxygen in higher animals including mammals are well known. A convenient and genetically well characterized small-animal model that exhibits reproducible, quantifiable oxygen reperfusion damage is currently lacking. Here we describe the dynamics of whole-organism metabolic recovery from anoxia in an insect, Drosophila melanogaster, and report that damage caused by oxygen reperfusion can be quantified in a novel but straightforward way. We monitored CO(2 emission (an index of mitochondrial activity and water vapor output (an index of neuromuscular control of the spiracles, which are valves between the outside air and the insect's tracheal system during entry into, and recovery from, rapid-onset anoxia exposure with durations ranging from 7.5 to 120 minutes. Anoxia caused a brief peak of CO(2 output followed by knock-out. Mitochondrial respiration ceased and the spiracle constrictor muscles relaxed, but then re-contracted, presumably powered by anaerobic processes. Reperfusion to sustained normoxia caused a bimodal re-activation of mitochondrial respiration, and in the case of the spiracle constrictor muscles, slow inactivation followed by re-activation. After long anoxia durations, both the bimodality of mitochondrial reactivation and the recovery of spiracular control were impaired. Repeated reperfusion followed by episodes of anoxia depressed mitochondrial respiratory flux rates and damaged the integrity of the spiracular control system in a dose-dependent fashion. This is the first time that physiological evidence of oxygen reperfusion damage has been described in an insect or any invertebrate. We suggest that some of the traditional approaches of insect respiratory biology, such as quantifying respiratory water loss, may facilitate using D. melanogaster as a convenient, well-characterized experimental model for studying the underlying biology and mechanisms of ischemia and

  4. Chlorinated tyrosine derivatives in insect cuticle

    DEFF Research Database (Denmark)

    Andersen, Svend Olav

    2004-01-01

    during sample hydrolysis. Mono- and dichlorotyrosine are also present in cuticular samples from other insect species, such as the beetle, Tenebrio molitor, the moth Hyalophora cecropia, the cockroach Blaberus craniifer, and the bug Rhodnius prolixus, but not in the sclerotized puparial cuticle...... of the blowfly, Calliphora vicina, or in sclerotized ootheca from the cockroach, Periplaneta americana. Cuticular sclerotization and formation of chlorotyrosines occur simultaneously in locust legs; sclerotized cuticles tend to have a higher content of chlorotyrosines than unsclerotized cuticles...

  5. Expansion and evolution of insect GMC oxidoreductases

    Directory of Open Access Journals (Sweden)

    Ko Wen-Ya

    2007-05-01

    Full Text Available Abstract Background The GMC oxidoreductases comprise a large family of diverse FAD enzymes that share a homologous backbone. The relationship and origin of the GMC oxidoreductase genes, however, was unknown. Recent sequencing of entire genomes has allowed for the evolutionary analysis of the GMC oxidoreductase family. Results Although genes that encode enzyme families are rarely linked in higher eukaryotes, we discovered that the majority of the GMC oxidoreductase genes in the fruit fly (D. melanogaster, mosquito (A. gambiae, honeybee (A. mellifera, and flour beetle (T. castaneum are located in a highly conserved cluster contained within a large intron of the flotillin-2 (Flo-2 gene. In contrast, the genomes of vertebrates and the nematode C. elegans contain few GMC genes and lack a GMC cluster, suggesting that the GMC cluster and the function of its resident genes are unique to insects or arthropods. We found that the development patterns of expression of the GMC cluster genes are highly complex. Among the GMC oxidoreductases located outside of the GMC gene cluster, the identities of two related enzymes, glucose dehydrogenase (GLD and glucose oxidase (GOX, are known, and they play major roles in development and immunity. We have discovered that several additional GLD and GOX homologues exist in insects but are remotely similar to fungal GOX. Conclusion We speculate that the GMC oxidoreductase cluster has been conserved to coordinately regulate these genes for a common developmental or physiological function related to ecdysteroid metabolism. Furthermore, we propose that the GMC gene cluster may be the birthplace of the insect GMC oxidoreductase genes. Through tandem duplication and divergence within the cluster, new GMC genes evolved. Some of the GMC genes have been retained in the cluster for hundreds of millions of years while others might have transposed to other regions of the genome. Consistent with this hypothesis, our analysis indicates

  6. Phase Coherence Analysis of Insect Flight

    CERN Document Server

    Shchekinova, E Y

    2009-01-01

    During insect flight a high--frequency wing oscillatory motion is generated. Here we present analysis of kinematic data of tethered Drosophila melanogaster flight. For a reliable detection of specific regimes of frequency variation we propose phase coherence method. The approach is generic and can be applied to nonstationary biological signals that feature multi- scale frequency variations. Our analysis reveals existence of distinct oscillatory modes.

  7. Phenotypic plasticity and diversity in insects

    OpenAIRE

    Moczek, Armin P.

    2010-01-01

    Phenotypic plasticity in general and polyphenic development in particular are thought to play important roles in organismal diversification and evolutionary innovation. Focusing on the evolutionary developmental biology of insects, and specifically that of horned beetles, I explore the avenues by which phenotypic plasticity and polyphenic development have mediated the origins of novelty and diversity. Specifically, I argue that phenotypic plasticity generates novel targets for evolutionary pr...

  8. Dynamic flight stability of hovering insects

    Institute of Scientific and Technical Information of China (English)

    Mao Sun; Jikang Wang; Yan Xiong

    2007-01-01

    The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the "rigid body" assumption. On the basis of the simplified equations of motion, the longitudinal dynamic flight stability of four insects (hoverfly, cranefly, dronefly and hawkmoth) in hovering flight is studied (the mass of the insects ranging from 11 to 1,648 mg and wingbeat frequency from 26 to 157Hz). The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenvector analysis are used to solve the equations of motion. The validity of the "rigid body" assumption is tested and how differencesin size and wing kinematics influence the applicability of the "rigid body" assumption is investigated. The primary findings are: (1) For insects considered in the present study and those with relatively high wingbeat frequency (hover-fly, drone fly and bumblebee), the "rigid body" assumptionis reasonable, and for those with relatively low wingbeatfrequency (cranefly and howkmoth), the applicability of the"rigid body" assumption is questionable. (2) The same three natural modes of motion as those reported recently for a bumblebee are identified, i.e., one unstable oscillatory mode,one stable fast subsidence mode and one stable slow subsidence mode. (3) Approximate analytical expressions of the eigenvalues, which give physical insight into the genesis of the natural modes of motion, are derived. The expressions identify the speed derivative Mu (pitching moment produced by unit horizontal speed) as the primary source of the unstable oscillatory mode and the stable fast subsidence mode and Zw (vertical force produced by unit vertical speed) as the primary source of the stable slow subsidence mode.

  9. Minor lipophilic compounds in edible insects

    Directory of Open Access Journals (Sweden)

    Monika Sabolová

    2016-07-01

    Full Text Available Contemporary society is faced with the question how to ensure suffiecient nutrition (quantity and quality for rapidly growing population. One solution can be consumption of edible insect, which can have very good nutritional value (dietary energy, protein, fatty acids, fibers, dietary minerals and vitamins composition. Some edible insects species, which contains a relatively large amount of fat, can have a potential to be a „good" (interesting, new source of minor lipophilic compounds such as sterols (cholesterol and phytosterols and tocopherols in our diet. For this reason, the objective of this work was to characterize the sterols and tocopherols composition of fat from larvae of edible insect Zophobas morio L. and Tenebrio mollitor L. Cholesterol and three phytosterols (campesterol, stigmasterol and β-sitosterol were reliably identified and quantified after hot saponification and derivatization by GC-MS. Other steroid compounds, including 5,6-trans-cholecalciferol were identified only according to the NIST library. Cholesterol was the predominant sterol in all analysed samples. Both types of larvae also contained high amount of phytosterols. Different region of origin had a no significant impact on sterols composition, while the effect of beetle genus was crucial. Tocopherols were analysed by reverse phase HPLC coupled with amperometric detection. Tocopherols content in mealworm larvae was lower than content in edible oils, but important from the nutritional point of view. Change of tocopherols composition was not observed during the storage under different conditions. Larvae of edible insect can be a potential good dietary source of cholesterol, but also vitamin D3 isomers, phytosterols and tocopherols.  

  10. Oxygen Reperfusion Damage in an Insect

    OpenAIRE

    2007-01-01

    The deleterious effects of anoxia followed by reperfusion with oxygen in higher animals including mammals are well known. A convenient and genetically well characterized small-animal model that exhibits reproducible, quantifiable oxygen reperfusion damage is currently lacking. Here we describe the dynamics of whole-organism metabolic recovery from anoxia in an insect, Drosophila melanogaster, and report that damage caused by oxygen reperfusion can be quantified in a novel but straightforward ...

  11. Insect inducible antimicrobial peptides and their applications.

    Science.gov (United States)

    Ezzati-Tabrizi, Reyhaneh; Farrokhi, Naser; Talaei-Hassanloui, Reza; Alavi, Seyed Mehdi; Hosseininaveh, Vahid

    2013-12-01

    Antimicrobial peptides (AMPs) are found as important components of the innate immune system (host defense) of all invertebrates. These peptides can be constitutively expressed or induced in response to microbial infections. Indeed, they vary in their amino acid sequences, potency and antimicrobial activity spectra. The smaller AMPs act greatly by disrupting the structure or function of microbial cell membranes. Here, the insect innate immune system with emphasis on inducible antimicrobial peptide properties against microbial invaders has been discussed.

  12. Recombinant fungal entomopathogen RNAi target insect gene.

    Science.gov (United States)

    Hu, Qiongbo; Wu, Wei

    2016-11-01

    RNA interference (RNAi) technology is considered as an alternative for control of pests. However, RNAi has not been used in field conditions yet, since delivering exogenous ds/siRNA to target pests is very difficult. The laboratory methods of introducing the ds/siRNA into insects through feeding, micro feeding / dripping and injecting cannot be used in fields. Transgenic crop is perhaps the most effective application of RNAi for pest control, but it needs long-time basic researches in order to reduce the cost and evaluate the safety. Therefore, transgenic microbe is maybe a better choice. Entomopathogenic fungi generally invade the host insects through cuticle like chemical insecticides contact insect to control sucking sap pests. Isaria fumosorosea is a common fungal entomopathogen in whitefly, Bemisia tabaci. We constructed a recombinant strain of I. fumosorosea expressing specific dsRNA of whitefly's TLR7 gene. It could silence the TLR7 gene and improve the virulence against whitefly. Transgenic fungal entomopathogen has shown great potential to attain the application of RNAi technology for pests control in fields. In the future, the research interests should be focused on the selection of susceptible target pests and their vital genes, and optimizing the methods for screening genes and recombinants as well.

  13. Insect cell culture in research: Indian scenario.

    Science.gov (United States)

    Sudeep, A B; Mourya, D T; Mishra, A C

    2005-06-01

    Insect cell cultures are widely used in viral diagnosis and biotechnology, for the production of recombinant proteins, viral pesticides and vaccines as well as in basic research in genetics, molecular biology, biochemistry, endocrinology and virology. Following KRP Singh's pioneering research in 1967, a large number of cell lines from diptera, hemiptera, and lepidopteran insects were established and characterized in India. With the availability of the modern tools in molecular biology and the advancements made in biotechnology, the indigenous cell lines may prove useful in creating a future without biohazardous chemical pesticides as well as producing life saving pharmaceuticals and vaccines for many diseases. This review summarizes information gathered regarding the insect cell lines established so far in India. It also covers the familiarization of the well characterized continuous cell lines and their potential applications. Special attention is given to virus susceptibility of the cell lines, the yield of virus with a comparative analysis with other conventional systems. The potential applications of dipteran and lepidopteran cell lines in agriculture and biotechnology are also briefly discussed for prospective studies.

  14. The ubiquity and ancestry of insect doublesex.

    Science.gov (United States)

    Price, Dana C; Egizi, Andrea; Fonseca, Dina M

    2015-08-17

    The doublesex (dsx) gene functions as a molecular switch at the base of the insect sex determination cascade, and triggers male or female somatic sexual differentiation in Drosophila. Having been reported from only seven current insect orders, the exact phylogenetic distribution of dsx within the largest Arthropod sub-phylum, the Hexapoda, is unknown. To understand the evolution of this integral gene relative to other arthropods, we tested for the presence of dsx within public EST and genome sequencing projects representative of all 32 hexapod orders. We find the dsx gene to be ubiquitous, with putative orthologs recovered from 30 orders. Additionally, we recovered both alternatively spliced and putative paralogous dsx transcripts from several orders of hexapods, including basal lineages, indicating the likely presence of these characteristics in the hexapod common ancestor. Of note, other arthropods such as chelicerates and crustaceans express two dsx genes, both of which are shown to lack alternative splicing. Furthermore, we discovered a large degree of length heterogeneity in the common region of dsx coding sequences within and among orders, possibly resulting from lineage-specific selective pressures inherent to each taxon. Our work serves as a valuable resource for understanding the evolution of sex determination in insects.

  15. Genitalia-associated microbes in insects.

    Science.gov (United States)

    Otti, Oliver

    2015-03-01

    In sexual reproduction different types of symbiotic relationships between insects and microbes have become established. For example, some bacteria have evolved almost exclusive vertical transmission and even define the compatibility of insect mating partners. Many strictly sexually transmitted diseases have also been described in insects. Apart from such rather specific relationships the role of opportunistic infections in the reproductive process has been widely neglected. Opportunistic microbes transmitted passively during mating might impose an energetic cost, as the immune system will need to be alert and will use resources to fight potential intruders. Through mating wounds and contaminated reproductive organs opportunistic microbes might be transferred to mating partners and even enter the body cavity. Females as the "receiving" sex are particularly likely to have evolved adaptations to avoid or reduce opportunistic infections. Males of several species show highly complex seminal fluids, which as well as containing components that influence a males' fertilization success, also possess antimicrobial substances. The role of antimicrobials in the reproductive process is not well understood. Some evidence hints at the protection of sperm against microbes, indicating a role for natural selection in shaping the evolution of reproductive traits. By highlighting the potential importance of microbes in sexual selection and their role in reproduction in general I will make a case for studies in sexual selection, especially the ones investigating postcopulatory processes, that should incorporate environmental, as well as genotypic variation, in reproductive traits.

  16. The Azadirachtins: potent insect growth inhibitors

    Directory of Open Access Journals (Sweden)

    Heinz Rembold

    1987-01-01

    Full Text Available In the course of their coevolution with insects, plants have learnt to protect themselves by chemical means. Semiochemical act as antifeedants or deterrents, others by disrupting growth and development. By use of the Epilachna varivestis bioassay we isolated from Azadirachta indica seed a group of triterpenoids which interfee with larval growth and development in ppm range. Main components are the azadirachtins A and B with identical biological activity. Various other azadirachtins were obtained, either as minor seed components or by chemical modification of the naturally occuring compounds. Structure vs. activity relation studies enabled us to postulate a basic structural element that should still be biologically active and with much simpler chemical structure than natural compounds. What underlies the biological activity of these insect growth inhibitors? Their interference with the hormonal regulation of development and reproduction has been studied in Locusta migratoria and Rhodnius prolixus. In addition, tritiated dihydroazadirachtin A was used. With this approach, a precise correlation between administered dose, resulting effects, and retention of the compound was established. The azadirachtins either interrupt, delay, or deviate whole developmental programs. Results from these studies provide another chemical probe for studies in insect endocrinology and physiology.

  17. Ecological interaction between insect pests, climatic factors and plant traits on abundance of beneficial insects in paddy field

    Directory of Open Access Journals (Sweden)

    Norazliza, R.

    2016-04-01

    Full Text Available The presences of beneficial insects in the paddy field are very important for the ecological systems of paddy field as those insects could help managing the population of the pests. Hence, it will reduce the dependence on pesticides usage to combat the population of insect pests. This study was aimed to study on ecological interaction between environmental factors such as insect pests, plant height, rainfall, temperature and humidity with abundance of beneficial insects in paddy field of Sungai Burong, Tanjung Karang, Selangor for two seasons of paddy planting. Low number of insects composition were recorded in paddy field at Sungai Burong during the vegetative phase and highest during the reproductive and maturity phases for two seasons of paddy planting. The trend of mean composition of insects were gradually increasing from vegetative to maturity phases while, the ecological interaction between insect pests, climatic factors and plant traits were acceptable as good predictor for all beneficial insects collected in this study namely Zygoptera, Gerridae, Coccinellidae and Staphylinidae except for Anisoptera. Therefore, consideration on several stated factors by maintaining or conserving ecology and controlling practices in good manner in paddy field has high potential and more reliable to control insect pests effectively using beneficial insects.

  18. Application of Genomics for Understanding Plant Virus-Insect Vector Interactions and Insect Vector Control.

    Science.gov (United States)

    Kaur, Navneet; Hasegawa, Daniel K; Ling, Kai-Shu; Wintermantel, William M

    2016-10-01

    The relationships between plant viruses and their vectors have evolved over the millennia, and yet, studies on viruses began virus and vector interactions even more recently. The advent of next generation sequencing, including rapid genome and transcriptome analysis, methods for evaluation of small RNAs, and the related disciplines of proteomics and metabolomics offer a significant shift in the ability to elucidate molecular mechanisms involved in virus infection and transmission by insect vectors. Genomic technologies offer an unprecedented opportunity to examine the response of insect vectors to the presence of ingested viruses through gene expression changes and altered biochemical pathways. This review focuses on the interactions between viruses and their whitefly or thrips vectors and on potential applications of genomics-driven control of the insect vectors. Recent studies have evaluated gene expression in vectors during feeding on plants infected with begomoviruses, criniviruses, and tospoviruses, which exhibit very different types of virus-vector interactions. These studies demonstrate the advantages of genomics and the potential complementary studies that rapidly advance our understanding of the biology of virus transmission by insect vectors and offer additional opportunities to design novel genetic strategies to manage insect vectors and the viruses they transmit.

  19. Monitoring the agricultural landscape for insect resistance

    Science.gov (United States)

    Casas, Joseph; Glaser, J. A.; Copenhaver, Ken

    Farmers in 25 countries on six continents are using plant biotechnology to solve difficult crop production challenges and conserve the environment. In fact, 13.3 million farmers, which include 90 percent of the farming in developing countries, choose to plant biotech crops. Over the past decade, farmers increased area planted in genetically modified (GM) crops by more than 10 percent each year, thus increasing their farm income by more than 44 billion US dollars (1996-2007), and achieved economic, environmental and social benefits in crops such as soybeans, canola, corn and cotton. To date, total acres of biotech crops harvested exceed more than 2 billion with a proven 13-year history of safe use. Over the next decade, expanded adoption combined with current research on 57 crops in 63 countries will broaden the advantages of genetically modified foods for growers, consumers and the environment. Genetically modified (GM) crops with the ability to produce toxins lethal to specific insect pests are covering a larger percentage of the agricultural landscape every year. The United States department of Agriculture (USDA) estimated that 63 percent of corn and 65 percent of cotton contained these specific genetic traits in 2009. The toxins could protect billions of dollars of loss from insect damage for crops valued at greater than 165 billion US dollars in 2008. The stable and efficient production of these crops has taken on even more importance in recent years with their use, not only as a food source, but now also a source of fuel. It is in the best interest of the United States Environmental Protection Agency (USEPA) to ensure the continued efficacy of toxin producing GM crops as their use reduces pesticides harmful to humans and animals. However, population genetics models have indicated the risk of insect pests developing resistance to these toxins if a high percentage of acreage is grown in these crops. The USEPA is developing methods to monitor the agricultural

  20. Allergic risks of consuming edible insects: A systematic review.

    Science.gov (United States)

    Ribeiro, José Carlos; Cunha, Luís Miguel; Sousa-Pinto, Bernardo; Fonseca, João

    2017-06-27

    The expected future demand for food and animal-derived protein will require environment-friendly novel food sources with high nutritional value. Insects may be one of such novel food sources. However, there needs to be an assessment of the risks associated with their consumption, including allergic risks. Therefore, we performed a systematic review aiming to analyse current data available regarding the allergic risks of consuming insects. We reviewed all reported cases of food allergy to insects, and studied the possibility of cross-reactivity and co-sensitisation between edible insects, crustaceans and house dust mites. We analysed a total of 25 articles - eight assessing the cross-reactivity/co-sensitisation between edible insects, crustaceans and house dust mites; three characterizing allergens in edible insects and 14 case reports, describing case series or prevalence studies of food allergy caused by insects. Cross-reactivity/co-sensitisation between edible insects and crustaceans seems to be clinically relevant, while it is still unknown if co-sensitisation between house dust mites and edible insects can lead to a food allergy. Additionally, more information is also needed about the molecular mechanisms underlying food allergy to insects, although current data suggest that an important role is played by arthropod pan-allergens such as tropomyosin or arginine kinase. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Genomics of adaptation to host-plants in herbivorous insects.

    Science.gov (United States)

    Simon, Jean-Christophe; d'Alençon, Emmanuelle; Guy, Endrick; Jacquin-Joly, Emmanuelle; Jaquiéry, Julie; Nouhaud, Pierre; Peccoud, Jean; Sugio, Akiko; Streiff, Réjane

    2015-11-01

    Herbivorous insects represent the most species-rich lineages of metazoans. The high rate of diversification in herbivorous insects is thought to result from their specialization to distinct host-plants, which creates conditions favorable for the build-up of reproductive isolation and speciation. These conditions rely on constraints against the optimal use of a wide range of plant species, as each must constitute a viable food resource, oviposition site and mating site for an insect. Utilization of plants involves many essential traits of herbivorous insects, as they locate and select their hosts, overcome their defenses and acquire nutrients while avoiding intoxication. Although advances in understanding insect-plant molecular interactions have been limited by the complexity of insect traits involved in host use and the lack of genomic resources and functional tools, recent studies at the molecular level, combined with large-scale genomics studies at population and species levels, are revealing the genetic underpinning of plant specialization and adaptive divergence in non-model insect herbivores. Here, we review the recent advances in the genomics of plant adaptation in hemipterans and lepidopterans, two major insect orders, each of which includes a large number of crop pests. We focus on how genomics and post-genomics have improved our understanding of the mechanisms involved in insect-plant interactions by reviewing recent molecular discoveries in sensing, feeding, digesting and detoxifying strategies. We also present the outcomes of large-scale genomics approaches aimed at identifying loci potentially involved in plant adaptation in these insects.

  2. Three-way interaction among plants, bacteria, and coleopteran insects.

    Science.gov (United States)

    Wielkopolan, Beata; Obrępalska-Stęplowska, Aleksandra

    2016-08-01

    Coleoptera, the largest and the most diverse Insecta order, is characterized by multiple adaptations to plant feeding. Insect-associated microorganisms can be important mediators and modulators of interactions between insects and plants. Interactions between plants and insects are highly complex and involve multiple factors. There are various defense mechanisms initiated by plants upon attack by herbivorous insects, including the development of morphological structures and the synthesis of toxic secondary metabolites and volatiles. In turn, herbivores have adapted to feeding on plants and further sophisticated adaptations to overcome plant responses may continue to evolve. Herbivorous insects may detoxify toxic phytocompounds, sequester poisonous plant factors, and alter their own overall gene expression pattern. Moreover, insects are associated with microbes, which not only considerably affect insects, but can also modify plant defense responses to the benefit of their host. Plants are also frequently associated with endophytes, which may act as bioinsecticides. Therefore, it is very important to consider the factors influencing the interaction between plants and insects. Herbivorous insects cause considerable damage to global crop production. Coleoptera is the largest and the most diverse order in the class Insecta. In this review, various aspects of the interactions among insects, microbes, and plants are described with a focus on coleopteran species, their bacterial symbionts, and their plant hosts to demonstrate that many factors contribute to the success of coleopteran herbivory.

  3. Phylogenomics resolves the timing and pattern of insect evolution.

    Science.gov (United States)

    Misof, Bernhard; Liu, Shanlin; Meusemann, Karen; Peters, Ralph S; Donath, Alexander; Mayer, Christoph; Frandsen, Paul B; Ware, Jessica; Flouri, Tomáš; Beutel, Rolf G; Niehuis, Oliver; Petersen, Malte; Izquierdo-Carrasco, Fernando; Wappler, Torsten; Rust, Jes; Aberer, Andre J; Aspöck, Ulrike; Aspöck, Horst; Bartel, Daniela; Blanke, Alexander; Berger, Simon; Böhm, Alexander; Buckley, Thomas R; Calcott, Brett; Chen, Junqing; Friedrich, Frank; Fukui, Makiko; Fujita, Mari; Greve, Carola; Grobe, Peter; Gu, Shengchang; Huang, Ying; Jermiin, Lars S; Kawahara, Akito Y; Krogmann, Lars; Kubiak, Martin; Lanfear, Robert; Letsch, Harald; Li, Yiyuan; Li, Zhenyu; Li, Jiguang; Lu, Haorong; Machida, Ryuichiro; Mashimo, Yuta; Kapli, Pashalia; McKenna, Duane D; Meng, Guanliang; Nakagaki, Yasutaka; Navarrete-Heredia, José Luis; Ott, Michael; Ou, Yanxiang; Pass, Günther; Podsiadlowski, Lars; Pohl, Hans; von Reumont, Björn M; Schütte, Kai; Sekiya, Kaoru; Shimizu, Shota; Slipinski, Adam; Stamatakis, Alexandros; Song, Wenhui; Su, Xu; Szucsich, Nikolaus U; Tan, Meihua; Tan, Xuemei; Tang, Min; Tang, Jingbo; Timelthaler, Gerald; Tomizuka, Shigekazu; Trautwein, Michelle; Tong, Xiaoli; Uchifune, Toshiki; Walzl, Manfred G; Wiegmann, Brian M; Wilbrandt, Jeanne; Wipfler, Benjamin; Wong, Thomas K F; Wu, Qiong; Wu, Gengxiong; Xie, Yinlong; Yang, Shenzhou; Yang, Qing; Yeates, David K; Yoshizawa, Kazunori; Zhang, Qing; Zhang, Rui; Zhang, Wenwei; Zhang, Yunhui; Zhao, Jing; Zhou, Chengran; Zhou, Lili; Ziesmann, Tanja; Zou, Shijie; Li, Yingrui; Xu, Xun; Zhang, Yong; Yang, Huanming; Wang, Jian; Wang, Jun; Kjer, Karl M; Zhou, Xin

    2014-11-07

    Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relations hips. We dated the origin of insects to the Early Ordovician [~479 million years ago (Ma)], of insect flight to the Early Devonian (~406 Ma), of major extant lineages to the Mississippian (~345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects.

  4. Scale insect host ranges are broader in the tropics.

    Science.gov (United States)

    Hardy, Nate B; Peterson, Daniel A; Normark, Benjamin B

    2015-12-01

    The specificity of the interactions between plants and their consumers varies considerably. The evolutionary and ecological factors underlying this variation are unclear. Several potential explanatory factors vary with latitude, for example plant species richness and the intensity of herbivory. Here, we use comparative phylogenetic methods to test the effect of latitude on host range in scale insects. We find that, on average, scale insects that occur in lower latitudes are more polyphagous. This result is at odds with the general pattern of greater host-plant specificity of insects in the tropics. We propose that this disparity reflects a high cost for host specificity in scale insects, stemming from unusual aspects of scale insect life history, for example, passive wind-driven dispersal. More broadly, the strong evidence for pervasive effects of geography on host range across insect groups stands in stark contrast to the weak evidence for constraints on host range due to genetic trade-offs.

  5. Insect gut microbiome - An unexploited reserve for biotechnological application

    Institute of Scientific and Technical Information of China (English)

    Muthukalingan Krishnan; Chinnapandi Bharathiraja; Jeyaraj Pandiarajan; Vimalanathan Arun Prasanna; Jeyaprakash Rajendhran; Paramasamy Gunasekaran

    2014-01-01

    Metagenomics research has been developed over the past decade to elucidate the genomes of the uncultured microorganisms with an aim of understanding microbial ecology. On the other hand, it has also been provoked by the increasing biotechnological demands for novel enzymes, antibiotic and signal mimics. The gut microbiota of insects plays crucial roles in the growth, development and environmental adaptation to the host insects. Very recently, the insect microbiota and their genomes (microbiome), isolated from insects were recognized as a major genetic resources for bio-processing industry. Consequently, the exploitation of insect gut microbiome using metagenomic approaches will enable us to find novel biocatalysts and to develop innovative strategies for identifying smart molecules for biotechnological applications. In this review, we discuss the critical footstep in extraction and purification of metagenomic DNA from insect gut, construction of metagenomic libraries and screening procedure for novel gene identification. Recent innovations and potential applications in bioprocess industries are highlighted.

  6. Tracing the evolutionary origins of insect renal function.

    Science.gov (United States)

    Halberg, Kenneth A; Terhzaz, Selim; Cabrero, Pablo; Davies, Shireen A; Dow, Julian A T

    2015-04-21

    Knowledge on neuropeptide receptor systems is integral to understanding animal physiology. Yet, obtaining general insight into neuropeptide signalling in a clade as biodiverse as the insects is problematic. Here we apply fluorescent analogues of three key insect neuropeptides to map renal tissue architecture across systematically chosen representatives of the major insect Orders, to provide an unprecedented overview of insect renal function and control. In endopterygote insects, such as Drosophila, two distinct transporting cell types receive separate neuropeptide signals, whereas in the ancestral exopterygotes, a single, general cell type mediates all signals. Intriguingly, the largest insect Order Coleoptera (beetles) has evolved a unique approach, in which only a small fraction of cells are targets for neuropeptide action. In addition to demonstrating a universal utility of this technology, our results reveal not only a generality of signalling by the evolutionarily ancient neuropeptide families but also a clear functional separation of the types of cells that mediate the signal.

  7. Insect gut microbiome – An unexploited reserve for biotechnological application

    Directory of Open Access Journals (Sweden)

    Muthukalingan Krishnan

    2014-05-01

    Full Text Available Metagenomics research has been developed over the past decade to elucidate the genomes of the uncultured microorganisms with an aim of understanding microbial ecology. On the other hand, it has also been provoked by the increasing biotechnological demands for novel enzymes, antibiotic and signal mimics. The gut microbiota of insects plays crucial roles in the growth, development and environmental adaptation to the host insects. Very recently, the insect microbiota and their genomes (microbiome, isolated from insects were recognized as a major genetic resources for bio-processing industry. Consequently, the exploitation of insect gut microbiome using metagenomic approaches will enable us to find novel biocatalysts and to develop innovative strategies for identifying smart molecules for biotechnological applications. In this review, we discuss the critical footstep in extraction and purification of metagenomic DNA from insect gut, construction of metagenomic libraries and screening procedure for novel gene identification. Recent innovations and potential applications in bioprocess industries are highlighted.

  8. Delivery of intrahemocoelic peptides for insect pest management.

    Science.gov (United States)

    Bonning, Bryony C; Chougule, Nanasaheb P

    2014-02-01

    The extensive use of chemical insecticides for insect pest management has resulted in insecticide resistance now being recorded in >500 species of insects and mites. Although gut-active toxins such as those derived from Bacillus thuringiensis (Bt) have been successfully used for insect pest management, a diverse range of insect-specific insecticidal peptides remains an untapped resource for pest management efforts. These toxins act within the insect hemocoel (body cavity) and hence require a delivery system to access their target site. Here, we summarize recent developments for appropriate delivery of such intrahemocoelic insect toxins, via fusion to a second protein such as a plant lectin or a luteovirus coat protein for transcytosis across the gut epithelium, or via entomopathogenic fungi.

  9. 桃蚜虫霉病始发期的初始感染与接触传染%Primary infection and contagious transmission of the Entomophthorales at the early stage of Myzus persicae mycosis

    Institute of Scientific and Technical Information of China (English)

    尚素微; 冯明光

    2006-01-01

    自2002年10月至2005年5月在杭州上空诱获桃蚜(Myzus persicae)的迁飞性有翅蚜 2351头,将其带回室内在(21±1)℃和12L:12D 条件下单头饲养12d,其中639头在定殖后7 d内发病死亡,初始感染率达27.2%.在病死有翅蚜中,99.4%系5种蚜科专化性虫霉侵染所致,新蚜虫疠霉(Pandora neoaphidis)的发生比例高达81.4%.带病迁飞的有翅蚜在发病死亡前具有一定生殖力,定殖后第6天平均累计产若蚜(2.4±0.13)头,远低于同期未带病有翅蚜产下的(11.6±0.33)头.在带病有翅蚜建立的后代蚜群中,接触传染在母蚜死亡2 d后即可见到.在定殖后第12天,二级感染占总观察蚜群数的13.3%,三级感染占总观察蚜群数的4.4%,占二级感染蚜群数的33.3%.此时,未带病有翅蚜的后代蚜群的平均活蚜数达(50.6±2.30)头,而带病有翅蚜的后代蚜群平均仅有(21.5±1.98)头.结果表明,虫霉病能够通过寄主带病迁飞传至寄主迁入地,并在后代蚜群中相互传染而起到调节蚜虫数量增长的作用.

  10. Broomcorn millet grain cultures of the obligate aphid pathogen Zoophthora anhuiensis (Entomophthorales) and their infectivity to Myzus persicae ( Hemiptera: Aphididae)%安徽虫瘟霉的黍米培养及其对桃蚜的侵染力

    Institute of Scientific and Technical Information of China (English)

    鲍佳生; 冯明光

    2006-01-01

    安徽虫瘟霉Zoophthora anhuiensis(Li)Humber是较难人工培养的蚜虫专化性病原真菌.将灭菌并适度熟化的黍米Panicum miliaceum L.作为固体基质与挑碎的安徽虫瘟霉平板菌落混合,在20℃和12L:12D的温光条件下静止固体培养,获得了产孢潜能大、杀蚜活性强的米粒培养物.培养7天的黍米的产孢量达13.0×104个孢子/粒,产孢持续时间长达6天.用此黍米培养物弹射的孢子对桃蚜Myzus persicae(Sulzer)若蚜进行7.9~134.9个孢子/mm2共9个剂量的孢子浴接种,所获数据很好拟合时间-剂量-死亡率模型.接种后第5~7天各天的LC50依次为59.8,39.5和33.5个孢子/mm2,LC90依次为354,234和198个孢子/mm2.在57.7~134.9个孢子/mm2的接种剂量范围内,致死中时LT50从5.1天下降到4.3天.由此表明,安徽虫温霉的黍米培养不仅简单易行,而且菌种的产孢和侵染生物学特性在培养物中被充分体现,每颗米粒如同自然罹病而死的蚜尸,值得进一步研究开发和利用.

  11. UV-induced ecological response and COⅠ-Ⅱ mutation of Myzus persicae%紫外线诱导对桃蚜生态学及线粒体基因COⅠ-Ⅱ突变的影响

    Institute of Scientific and Technical Information of China (English)

    都二霞; 赵惠燕; 郭剑文

    2007-01-01

    为了揭示紫外线诱导桃蚜的生态学及分子变异的遗传效应,以在正常环境中生长的桃蚜为对照,研究了紫外线不同辐射强度(15,30,45 W)和时间(2,6 h)对桃蚜(Myzus persicae)生态学参数以及线粒体基因 COⅠ-Ⅱ突变的影响.结果表明,不同辐射处理对桃蚜F2代的主要种群参数均有不同程度的影响:当辐射时间为2 h时,紫外线强度为15 W处理的桃蚜种群内禀增长率最高,达0.265;当辐射时间为6 h时,内禀增长率随紫外线辐射强度的增加而缓慢上升.与对照相比,低强度(15 W)紫外线处理桃蚜的平均世代周期和净增殖率较其他处理明显增加.对紫外线诱导桃蚜线粒体基因COⅠ-Ⅱ进行测序可知,15 W紫外线辐射2 h处理桃蚜的线粒体基因COⅠ-Ⅱ发生单碱基突变,而45 W紫外线辐射6 h处理桃蚜的线粒体基因COⅠ-Ⅱ突变位点达9个.说明紫外线诱导对当代桃蚜的生态学和分子变异的影响已经遗传给了后代.

  12. Flower Constancy, Insect Psychology, and Plant Evolution

    Science.gov (United States)

    Chittka, Lars; Thomson, James D.; Waser, Nickolas M.

    Individuals of some species of pollinating insects tend to restrict their visits to only a few of the available plant species, in the process bypassing valuable food sources. The question of why this flower constancy exists is a rich and important one with implications for the organization of natural communities of plants, floral evolution, and our understanding of the learning processes involved in finding food. Some scientists have assumed that flower constancy is adaptive per se. Others argued that constancy occurs because memory capacity for floral features in insects is limited, but attempts to identify the limitations often remained rather simplistic. We elucidate now different sensory and motor memories from natural foraging tasks are stored and retrieved, using concepts from modern learning science and visual search, and conclude that flower constancy is likely to have multiple causes. Possible constraints favoring constancy are interference sensitivity of short-term memory, and temporal limitations on retrieving information from long-term memory as rapidly as from short-term memory, but further empirical evidence is needed to substantiate these possibilities. In addition, retrieving memories may be slower and more prone to errors when there are several options than when an insect copes with only a single task. In addition to memory limitations, we also point out alternative explanations for flower constancy. We then consider the way in which floral parameters, such as interplant distances, nectar rewards, flower morphology, and floral color (as seen through bees' eyes) affect constancy. Finally, we discuss the implications of pollinator constancy for plant evolution. To date there is no evidence that flowers have diverged to favor constancy, although the appropriate tests may not have yet been conducted. However, there is good evidence against the notion that pollinator constancy is involved in speciation or maintenance of plant species integrity.

  13. Helminthes and insects: maladies or therapies.

    Science.gov (United States)

    El-Tantawy, Nora L

    2015-02-01

    By definition, parasites cause harm to their hosts. But, considerable evidence from ancient traditional medicine has supported the theory of using parasites and their products in treating many diseases. Maggots have been used successfully to treat chronic, long-standing, infected wounds which failed to respond to conventional treatment by many beneficial effects on the wound including debridement, disinfection, and healing enhancement. Maggots are also applied in forensic medicine to estimate time between the death and discovery of a corpse and in entomotoxicology involving the potential use of insects as alternative samples for detecting drugs and toxins in death investigations. Leeches are segmented invertebrates, famous by their blood-feeding habits and used in phlebotomy to treat various ailments since ancient times. Leech therapy is experiencing resurgence nowadays in health care principally in plastic and reconstructive surgery. Earthworms provide a source of medicinally useful products with potential antimicrobial, antiviral, and anticancer properties. Lumbrokinases are a group of fibrinolytic enzymes isolated and purified from earthworms capable of degrading plasminogen-rich and plasminogen-free fibrin and so can be used to treat various conditions associated with thrombotic diseases. Helminth infection has been proved to have therapeutic effects in both animal and human clinical trials with promising evidence in treating many allergic diseases and can block the induction of or reduce the severity of some autoimmune disorders as Crohn's disease or ulcerative colitis. What is more, venomous arthropods such as scorpions, bees, wasps, spiders, ants, centipedes, snail, beetles, and caterpillars. The venoms and toxins from these arthropods provide a promising source of natural bioactive compounds which can be employed in the development of new drugs to treat diseases as cancer. The possibility of using these active molecules in biotechnological processes can

  14. Design and mechanical properties of insect cuticle.

    Science.gov (United States)

    Vincent, Julian F V; Wegst, Ulrike G K

    2004-07-01

    Since nearly all adult insects fly, the cuticle has to provide a very efficient and lightweight skeleton. Information is available about the mechanical properties of cuticle-Young's modulus of resilin is about 1 MPa, of soft cuticles about 1 kPa to 50 MPa, of sclerotised cuticles 1-20 GPa; Vicker's Hardness of sclerotised cuticle ranges between 25 and 80 kgf mm(-2); density is 1-1.3 kg m(-3)-and one of its components, chitin nanofibres, the Young's modulus of which is more than 150 GPa. Experiments based on fracture mechanics have not been performed although the layered structure probably provides some toughening. The structural performance of wings and legs has been measured, but our understanding of the importance of buckling is lacking: it can stiffen the structure (by elastic postbuckling in wings, for example) or be a failure mode. We know nothing of fatigue properties (yet, for instance, the insect wing must undergo millions of cycles, flexing or buckling on each cycle). The remarkable mechanical performance and efficiency of cuticle can be analysed and compared with those of other materials using material property charts and material indices. Presented in this paper are four: Young's modulus-density (stiffness per unit weight), specific Young's modulus-specific strength (elastic hinges, elastic energy storage per unit weight), toughness-Young's modulus (fracture resistance under various loading conditions), and hardness (wear resistance). In conjunction with a structural analysis of cuticle these charts help to understand the relevance of microstructure (fibre orientation effects in tendons, joints and sense organs, for example) and shape (including surface structure) of this fibrous composite for a given function. With modern techniques for analysis of structure and material, and emphasis on nanocomposites and self-assembly, insect cuticle should be the archetype for composites at all levels of scale.

  15. Evolutionary biology and genetic techniques for insect control

    OpenAIRE

    Leftwich, Philip; Bolton, Michael; Chapman, Tracey

    2015-01-01

    Abstract The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutil...

  16. Biocontrol: The Potential of Entomophilic Nematodes in Insect Management

    OpenAIRE

    Webster, John M.

    1980-01-01

    A review of the development of entomophilic nematology and a commentary on the potential of entomophilic nematodes in controlling insect pests. The paper considers some of the major contributions to our knowledge of entomophilic nematology; factors involved in insect pest management and how they are applicable to the use of nematodes; nematodes which are most promising as biological control agents; and problems to be solved to facilitate the use of entomophilic nematodes in insect management.

  17. Biocontrol: the potential of entomophilic nematodes in insect management.

    Science.gov (United States)

    Webster, J M

    1980-10-01

    A review of the development of entomophilic nematology and a commentary on the potential of entomophilic nematodes in controlling insect pests. The paper considers some of the major contributions to our knowledge of entomophilic nematology; factors involved in insect pest management and how they are applicable to the use of nematodes; nematodes which are most promising as biological control agents; and problems to be solved to facilitate the use of entomophilic nematodes in insect management.

  18. On methodology of foraging behavior of pollinating insects

    OpenAIRE

    Yanbing Gong; Shuangquan Huang

    2007-01-01

    Foraging behavior of pollinating insects can directly influence plant–pollinator interactions in many aspects, thus studies on pollinator behavior are important for understanding plant diversity and ecological processes of plant reproduction. In this paper, we describe the characteristics of major pollinating insects and discuss the methods for studying foraging behavior of pollinating insects and factors potentially influencing pollinator behaviors. We also suggest some practical methods for...

  19. Biocontrol: The Potential of Entomophilic Nematodes in Insect Management

    OpenAIRE

    Webster, John M.

    1980-01-01

    A review of the development of entomophilic nematology and a commentary on the potential of entomophilic nematodes in controlling insect pests. The paper considers some of the major contributions to our knowledge of entomophilic nematology; factors involved in insect pest management and how they are applicable to the use of nematodes; nematodes which are most promising as biological control agents; and problems to be solved to facilitate the use of entomophilic nematodes in insect management.

  20. Climate Change Effects Overwintering of Insects

    DEFF Research Database (Denmark)

    Vukasinovic, Dragana

    Climate change is modifying winter conditions rapidly and predicting species’ reactions to global warming has been the “the holy grail” of climate sciences, especially for managed systems, like agro-ecosystems. Intuitively, increased winter temperatures should release insects from coldinduced...... with decreasing body mass.Post-winter performance of H. axyridis was positively affected by mild winter conditions such that higher feeding capacity and shorter pre-oviposition period was recorded, but may be affected negatively by cold winters, which caused chill injury related mortality (recorded after winter...