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Sample records for insect leptinotarsa decemlineata

  1. Attacks by a piercing-sucking insect (Myzus persicae Sultzer) or a chewing insect (Leptinotarsa decemlineata Say) on potato plants (Solanum tuberosum L.) induce differential changes in volatile compound release and oxylipin synthesis.

    PubMed

    Gosset, Virginie; Harmel, Nicolas; Göbel, Cornelia; Francis, Frédéric; Haubruge, Eric; Wathelet, Jean-Paul; du Jardin, Patrick; Feussner, Ivo; Fauconnier, Marie-Laure

    2009-01-01

    Plant defensive strategies bring into play blends of compounds dependent on the type of attacker and coming from different synthesis pathways. Interest in the field is mainly focused on volatile organic compounds (VOCs) and jasmonic acid (JA). By contrast, little is known about the oxidized polyunsaturated fatty acids (PUFAs), such as PUFA-hydroperoxides, PUFA-hydroxides, or PUFA-ketones. PUFA-hydroperoxides and their derivatives might be involved in stress response and show antimicrobial activities. Hydroperoxides are also precursors of JA and some volatile compounds. In this paper, the differential biochemical response of a plant against insects with distinct feeding behaviours is characterized not only in terms of VOC signature and JA profile but also in terms of their precursors synthesized through the lipoxygenase (LOX)-pathway at the early stage of the plant response. For this purpose, two leading pests of potato with distinct feeding behaviours were used: the Colorado Potato Beetle (Leptinotarsa decemlineata Say), a chewing herbivore, and the Green Peach Aphid (Myzus persicae Sulzer), a piercing-sucking insect. The volatile signatures identified clearly differ in function with the feeding behaviour of the attacker and the aphid, which causes the smaller damages, triggers the emission of a higher number of volatiles. In addition, 9-LOX products, which are usually associated with defence against pathogens, were exclusively activated by aphid attack. Furthermore, a correlation between volatiles and JA accumulation and the evolution of their precursors was determined. Finally, the role of the insect itself on the plant response after insect infestation was highlighted.

  2. Sequencing, De Novo Assembly and Annotation of the Colorado Potato Beetle, Leptinotarsa decemlineata, Transcriptome

    PubMed Central

    Kumar, Abhishek; Congiu, Leonardo; Lindström, Leena; Piiroinen, Saija; Vidotto, Michele; Grapputo, Alessandro

    2014-01-01

    Background The Colorado potato beetle (Leptinotarsa decemlineata) is a major pest and a serious threat to potato cultivation throughout the northern hemisphere. Despite its high importance for invasion biology, phenology and pest management, little is known about L. decemlineata from a genomic perspective. We subjected European L. decemlineata adult and larval transcriptome samples to 454-FLX massively-parallel DNA sequencing to characterize a basal set of genes from this species. We created a combined assembly of the adult and larval datasets including the publicly available midgut larval Roche 454 reads and provided basic annotation. We were particularly interested in diapause-specific genes and genes involved in pesticide and Bacillus thuringiensis (Bt) resistance. Results Using 454-FLX pyrosequencing, we obtained a total of 898,048 reads which, together with the publicly available 804,056 midgut larval reads, were assembled into 121,912 contigs. We established a repository of genes of interest, with 101 out of the 108 diapause-specific genes described in Drosophila montana; and 621 contigs involved in insecticide resistance, including 221 CYP450, 45 GSTs, 13 catalases, 15 superoxide dismutases, 22 glutathione peroxidases, 194 esterases, 3 ADAM metalloproteases, 10 cadherins and 98 calmodulins. We found 460 putative miRNAs and we predicted a significant number of single nucleotide polymorphisms (29,205) and microsatellite loci (17,284). Conclusions This report of the assembly and annotation of the transcriptome of L. decemlineata offers new insights into diapause-associated and insecticide-resistance-associated genes in this species and provides a foundation for comparative studies with other species of insects. The data will also open new avenues for researchers using L. decemlineata as a model species, and for pest management research. Our results provide the basis for performing future gene expression and functional analysis in L. decemlineata and improve our

  3. Prevalence of Endosymbionts in Polish Populations of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

    PubMed

    Krawczyk, Krzysztof; Szymańczyk, Mateusz; Obrępalska-Stęplowska, Aleksandra

    2015-01-01

    Colorado potato beetle (CPB, Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) is one of the most serious insect pest feeding on wild and cultivated Solanaceae plants. This pest poses a significant threat to potato crops. CPB originated from North America but has become widespread and has adapted in new localizations. Currently, it is reported in many countries worldwide. Endosymbiotic bacteria might have an influence on insect adaptation to new conditions. They are known to play a role in invasiveness of insect hosts and to facilitate colonization of new niches; however, information on endosymbionts of the CPB is very limited. In this study, we screened CPB populations collected from 20 evenly distributed locations in Poland for the presence of Arsenophonus, Cardinium, Wolbachia, and Flavobacterium. We found the presence of Flavobacterium in the studied insects. Little is known about CPB-endosymbionts interactions, thus this study may provide a reference for future studies in this subject. PMID:26206894

  4. Prevalence of Endosymbionts in Polish Populations of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

    PubMed Central

    Krawczyk, Krzysztof; Szymańczyk, Mateusz; Obrępalska-Stęplowska, Aleksandra

    2015-01-01

    Colorado potato beetle (CPB, Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) is one of the most serious insect pest feeding on wild and cultivated Solanaceae plants. This pest poses a significant threat to potato crops. CPB originated from North America but has become widespread and has adapted in new localizations. Currently, it is reported in many countries worldwide. Endosymbiotic bacteria might have an influence on insect adaptation to new conditions. They are known to play a role in invasiveness of insect hosts and to facilitate colonization of new niches; however, information on endosymbionts of the CPB is very limited. In this study, we screened CPB populations collected from 20 evenly distributed locations in Poland for the presence of Arsenophonus, Cardinium, Wolbachia, and Flavobacterium. We found the presence of Flavobacterium in the studied insects. Little is known about CPB–endosymbionts interactions, thus this study may provide a reference for future studies in this subject. PMID:26206894

  5. Prevalence of Endosymbionts in Polish Populations of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

    PubMed

    Krawczyk, Krzysztof; Szymańczyk, Mateusz; Obrępalska-Stęplowska, Aleksandra

    2015-01-01

    Colorado potato beetle (CPB, Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) is one of the most serious insect pest feeding on wild and cultivated Solanaceae plants. This pest poses a significant threat to potato crops. CPB originated from North America but has become widespread and has adapted in new localizations. Currently, it is reported in many countries worldwide. Endosymbiotic bacteria might have an influence on insect adaptation to new conditions. They are known to play a role in invasiveness of insect hosts and to facilitate colonization of new niches; however, information on endosymbionts of the CPB is very limited. In this study, we screened CPB populations collected from 20 evenly distributed locations in Poland for the presence of Arsenophonus, Cardinium, Wolbachia, and Flavobacterium. We found the presence of Flavobacterium in the studied insects. Little is known about CPB-endosymbionts interactions, thus this study may provide a reference for future studies in this subject.

  6. Spatial and Temporal Potato Intensification Drives Insecticide Resistance in the Specialist Herbivore, Leptinotarsa decemlineata.

    PubMed

    Huseth, Anders S; Petersen, Jessica D; Poveda, Katja; Szendrei, Zsofia; Nault, Brian A; Kennedy, George G; Groves, Russell L

    2015-01-01

    Landscape-scale intensification of individual crops and pesticide use that is associated with this intensification is an emerging, environmental problem that is expected to have unequal effects on pests with different lifecycles, host ranges, and dispersal abilities. We investigate if intensification of a single crop in an agroecosystem has a direct effect on insecticide resistance in a specialist insect herbivore. Using a major potato pest, Leptinotarsa decemlineata, we measured imidacloprid (neonicotinoid) resistance in populations across a spatiotemporal crop production gradient where potato production has increased in Michigan and Wisconsin, USA. We found that concurrent estimates of area and temporal frequency of potato production better described patterns of imidacloprid resistance among L. decemlineata populations than general measures of agricultural production (% cropland, landscape diversity). This study defines the effects individual crop rotation patterns can have on specialist herbivore insecticide resistance in an agroecosystem context, and how impacts of intensive production can be estimated with general estimates of insecticide use. Our results provide empirical evidence that variation in the intensity of neonicotinoid-treated potato in an agricultural landscape can have unequal impacts on L. decemlineata insecticide insensitivity, a process that can lead to resistance and locally intensive insecticide use. Our study provides a novel approach applicable in other agricultural systems to estimate impacts of crop rotation, increased pesticide dependence, insecticide resistance, and external costs of pest management practices on ecosystem health.

  7. Spatial and Temporal Potato Intensification Drives Insecticide Resistance in the Specialist Herbivore, Leptinotarsa decemlineata.

    PubMed

    Huseth, Anders S; Petersen, Jessica D; Poveda, Katja; Szendrei, Zsofia; Nault, Brian A; Kennedy, George G; Groves, Russell L

    2015-01-01

    Landscape-scale intensification of individual crops and pesticide use that is associated with this intensification is an emerging, environmental problem that is expected to have unequal effects on pests with different lifecycles, host ranges, and dispersal abilities. We investigate if intensification of a single crop in an agroecosystem has a direct effect on insecticide resistance in a specialist insect herbivore. Using a major potato pest, Leptinotarsa decemlineata, we measured imidacloprid (neonicotinoid) resistance in populations across a spatiotemporal crop production gradient where potato production has increased in Michigan and Wisconsin, USA. We found that concurrent estimates of area and temporal frequency of potato production better described patterns of imidacloprid resistance among L. decemlineata populations than general measures of agricultural production (% cropland, landscape diversity). This study defines the effects individual crop rotation patterns can have on specialist herbivore insecticide resistance in an agroecosystem context, and how impacts of intensive production can be estimated with general estimates of insecticide use. Our results provide empirical evidence that variation in the intensity of neonicotinoid-treated potato in an agricultural landscape can have unequal impacts on L. decemlineata insecticide insensitivity, a process that can lead to resistance and locally intensive insecticide use. Our study provides a novel approach applicable in other agricultural systems to estimate impacts of crop rotation, increased pesticide dependence, insecticide resistance, and external costs of pest management practices on ecosystem health. PMID:26030877

  8. Spatial and Temporal Potato Intensification Drives Insecticide Resistance in the Specialist Herbivore, Leptinotarsa decemlineata

    PubMed Central

    Huseth, Anders S.; Petersen, Jessica D.; Poveda, Katja; Szendrei, Zsofia; Nault, Brian A.; Kennedy, George G.; Groves, Russell L.

    2015-01-01

    Landscape-scale intensification of individual crops and pesticide use that is associated with this intensification is an emerging, environmental problem that is expected to have unequal effects on pests with different lifecycles, host ranges, and dispersal abilities. We investigate if intensification of a single crop in an agroecosystem has a direct effect on insecticide resistance in a specialist insect herbivore. Using a major potato pest, Leptinotarsa decemlineata, we measured imidacloprid (neonicotinoid) resistance in populations across a spatiotemporal crop production gradient where potato production has increased in Michigan and Wisconsin, USA. We found that concurrent estimates of area and temporal frequency of potato production better described patterns of imidacloprid resistance among L. decemlineata populations than general measures of agricultural production (% cropland, landscape diversity). This study defines the effects individual crop rotation patterns can have on specialist herbivore insecticide resistance in an agroecosystem context, and how impacts of intensive production can be estimated with general estimates of insecticide use. Our results provide empirical evidence that variation in the intensity of neonicotinoid-treated potato in an agricultural landscape can have unequal impacts on L. decemlineata insecticide insensitivity, a process that can lead to resistance and locally intensive insecticide use. Our study provides a novel approach applicable in other agricultural systems to estimate impacts of crop rotation, increased pesticide dependence, insecticide resistance, and external costs of pest management practices on ecosystem health. PMID:26030877

  9. Photoperiodic effects on diapause-associated gene expression trajectories in European Leptinotarsa decemlineata populations.

    PubMed

    Lehmann, P; Piiroinen, S; Kankare, M; Lyytinen, A; Paljakka, M; Lindström, L

    2014-10-01

    Behavioural and physiological changes during diapause, an important strategy of insects for surviving harsh seasonal conditions, have been intensively studied. The genetic and molecular mechanisms underpinning diapause development are less well known. We took a candidate gene approach to study prediapause gene expression patterns in the Colorado potato beetle (Leptinotarsa decemlineata), an invasive insect that has rapidly spread northwards to high seasonality environments. Newly eclosed beetles originating from southern (Italy) and northern (Russia) Europe were reared under short- [12 h light (L):12 h dark (D)] and long-day (18L:6D) photoperiods for 10 days. This time period includes the sensitive period for the photoperiodic induction and initiation of diapause. Gene expression trajectories of 12 diapause-related genes (regulatory, metabolic and stress-resistance) were analysed from 0-, 5- and 10-day-old beetles. Gene expression differences increased with age, deviating significantly between populations and photoperiods in 10-day-old beetles. The gene expression profiles, particularly those related to energy metabolism and stress-resistance, indicate that beetles originating from Russia also prepare for diapause under the long-day photoperiod and show qualitative differences in the diapausing phenotype. Our study shows that population-dependent differences seen in behavioural and physiological traits connected with diapause in L. decemlineata are also evident in the expression trajectories of diapause-related genes. PMID:24924142

  10. A complex of genes involved in adaptation of Leptinotarsa decemlineata larvae to induced potato defense.

    PubMed

    Petek, Marko; Turnšek, Neža; Gašparič, Meti Buh; Novak, Maruša Pompe; Gruden, Kristina; Slapar, Nina; Popovič, Tatjana; Štrukelj, Borut; Gruden, Kristina; Štrukelj, Borut; Jongsma, Maarten A

    2012-03-01

    The Colorado potato beetle (Leptinotarsa decemlineata) is the most important pest of potato in many areas of the world. One of the main reasons for its success lies in the ability of its larvae to counteract plant defense compounds. Larvae adapt to protease inhibitors (PIs) produced in potato leaves through substitution of inhibitor-sensitive digestive cysteine proteases with inhibitor-insensitive cysteine proteases. To get a broader insight into the basis of larval adaptation to plant defenses, we created a "suppression subtractive hybridisation" library using cDNA from the gut of L. decemlineata larvae fed methyl jasmonate-induced or uninduced potato leaves. Four hundred clones, randomly selected from the library, were screened for their relevance to adaptation with DNA microarray hybridizations. Selected enzyme systems of beetle digestion were further inspected for changes in gene expression using quantitative PCR and enzyme activity measurements. We identified two new groups of digestive cysteine proteases, intestains D and intestains E. Intestains D represent a group of structurally distinct digestive cysteine proteases, of which the tested members are strongly upregulated in response to induced plant defenses. Moreover, we found that other digestive enzymes also participate in adaptation, namely, cellulases, serine proteases, and an endopolygalacturonase. In addition, juvenile hormone binding protein-like (JHBP-like) genes were upregulated. All studied genes were expressed specifically in larval guts. In contrast to earlier studies that reported experiments based on PI-enriched artificial diets, our results increase understanding of insect adaptation under natural conditions.

  11. Characterization of two unrelated satellite DNA families in the Colorado potato beetle Leptinotarsa decemlineata (Coleoptera, Chrysomelidae).

    PubMed

    Lorite, Pedro; Torres, M Isabel; Palomeque, Teresa

    2013-10-01

    The Colorado potato beetle (Leptinotarsa decemlineata, family Chrysomelidae),a phytophagous insect, which feeds preferably on potatoes, constitutes a serious pest of this crop and causes extensive damage to tomatoes and egg plants. It has a remarkable ability to develop resistance quickly against insecticides and shows a diversified and flexible life history. Consequently, the control of this pest has become difficult, requiring the development of new alternative biotechnology-based strategies. Such strategies require a thorough knowledge of the beetle’s genome,including the repetitive DNA. Satellite DNA (stDNA), composed of long arrays of tandemly arranged repeat units, constitutes the major component of heterochromatin and is located mainly in centromeric and telomeric chromosomal regions. We have studied two different unrelated satellite-DNA families of which the consensus sequences were 295 and 109bp in length, named LEDE-I and LEDE-II, respectively.Both were AT-rich (70.8% and 71.6%, respectively). Predictive models of sequence-dependent DNA bending and the study of electrophoretic mobility on non-denaturing polyacrylamide gels have shown that the DNA was curved in both satellite-DNA families. Among other features, the chromosome localization of both stDNAs has been studied. In situ hybridization performed on meiotic and mitoticnuclei showed chromosomes, including the X chromosome, with zero, one, or two stDNAs. In recent years, it has been proposed that the repetitive DNA may play a key role in biological diversification processes. This is the first molecular and cytogenetic study conducted on L. decemlineata repetitive DNA and specifically on stDNA, which is one of the important constituents of eukaryotic genomes.

  12. Characterization of two unrelated satellite DNA families in the Colorado potato beetle Leptinotarsa decemlineata (Coleoptera, Chrysomelidae).

    PubMed

    Lorite, Pedro; Torres, M Isabel; Palomeque, Teresa

    2013-10-01

    The Colorado potato beetle (Leptinotarsa decemlineata, family Chrysomelidae),a phytophagous insect, which feeds preferably on potatoes, constitutes a serious pest of this crop and causes extensive damage to tomatoes and egg plants. It has a remarkable ability to develop resistance quickly against insecticides and shows a diversified and flexible life history. Consequently, the control of this pest has become difficult, requiring the development of new alternative biotechnology-based strategies. Such strategies require a thorough knowledge of the beetle’s genome,including the repetitive DNA. Satellite DNA (stDNA), composed of long arrays of tandemly arranged repeat units, constitutes the major component of heterochromatin and is located mainly in centromeric and telomeric chromosomal regions. We have studied two different unrelated satellite-DNA families of which the consensus sequences were 295 and 109bp in length, named LEDE-I and LEDE-II, respectively.Both were AT-rich (70.8% and 71.6%, respectively). Predictive models of sequence-dependent DNA bending and the study of electrophoretic mobility on non-denaturing polyacrylamide gels have shown that the DNA was curved in both satellite-DNA families. Among other features, the chromosome localization of both stDNAs has been studied. In situ hybridization performed on meiotic and mitoticnuclei showed chromosomes, including the X chromosome, with zero, one, or two stDNAs. In recent years, it has been proposed that the repetitive DNA may play a key role in biological diversification processes. This is the first molecular and cytogenetic study conducted on L. decemlineata repetitive DNA and specifically on stDNA, which is one of the important constituents of eukaryotic genomes. PMID:23448367

  13. Impact of chemical manipulation of tarsal liquids on attachment in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Geiselhardt, Stefanie F; Federle, Walter; Prüm, Bettina; Geiselhardt, Sven; Lamm, Stefan; Peschke, Klaus

    2010-04-01

    Insect tarsal attachment forces are thought to be influenced by the viscosity and surface tension of a thin film of adhesive liquid (wet adhesion). In beetles, this fluid has been shown to be composed mainly of lipophilic substances that are similar to the cuticular lipids. In this study we investigate whether and how the chemical composition of footprint lipids affects attachment forces in the Colorado potato beetle, Leptinotarsa decemlineata. After application of standardised mixtures of synthetic n-alkanes or alkenes, or a concentrated hydrocarbon extract to the surface of the elytra, we tested the beetles' attachment performance using a beam force transducer. The results show that only the unsaturated components, but not the straight-chained alkanes reduced friction forces, confirming that attachment performance is influenced by the chemical composition of the adhesive secretion. We estimated the volume of footprint droplets and calculated a mean thickness of the liquid layer of 0.04 microm. The measured friction exceeded the viscous and capillary force expected for a film of this thickness. Therefore, alternative mechanisms (i.e. shear-thinning and solid-like behaviour) for the generation of attachment forces and their dependence on the chemical composition of the liquid are discussed.

  14. Effect on non-host plants on movements of Colorado potato beetle, Leptinotarsa decemlineata (Say)

    SciTech Connect

    Cort, R.P.

    1982-01-01

    Movements of Colorado potato beetles, Leptinotarsa decemlineata, (Say) (Coleoptera: Chrysomelidae) were studied in experimental plots of potatoes planted in monocultures and in polycultures with beans and/or marigolds. Rates of movement into and out of plots of varying plant composition were measured by mark-recapture of adult beetles. The amount of emigration was not affected by the presence of non-host plants. However, there were significantly more beetles moving into the pure stands of potatoes than into the plots containing non-host plants. This pattern is consistent with the idea that non-host plants act to mask host plants from potential herbivores, but do not affect the insect once it has located a host plant. It is thus unlikely that marigolds or beans repel Colorado potato beetles, since an increase in emigration would be expected if this were true. Beans are more effective than marigolds at deterring immigration, and both non-host plants together have an additive effect greater than one alone.

  15. Identification of cytochrome P450 monooxygenase genes and their expression profiles in cyhalothrin-treated Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Shi, Xiao-Qin; Kong, Ye; Zhou, Li-Tao; Guo, Wen-Chao; Ahmat, Tursun; Li, Guo-Qing

    2013-11-01

    Based on a Leptinotarsa decemlineata transcriptome dataset and the GenBank sequences, a total of 74 cytochrome P450 monooxygenase genes (Cyps) were identified. These genes fell into CYP2 clan, mitochondrial clan, CYP3 clan and CYP4 clan, and were classified into 19 families and 35 subfamilies according to standard nomenclature. Two new families were discovered in CYP4 clan, and were named CYP412 and CYP413 respectively. Four new families that were recently discovered in Tribolium castaneum, including mitochondrial family CYP353, CYP3 clan families CYP345 and CYP347, and CYP4 clan family CYP350, were also found in L. decemlineata. The phylogenetic trees of CYPs from L. decemlineata and other representative insect species were constructed, and these trees provided evolutionary insight for the genetic distance. Our results facilitate further researches to understand the functions and evolution of L. decemlineata Cyp genes. In order to find cyhalothrin-inducible Cyp genes, the expression levels of Cyps belonging to CYP12, CYP6, CYP9 and CYP4 families were determined by quantitative reverse transcriptase-PCR in cyhalothrin-treated and control fourth-instar larvae. Nine Cyp genes, i.e., Cyp12H2, Cyp6BH2, Cyp6BJ1, Cyp6BQ17, Cyp6EG1, Cyp6EH1, Cyp6EJ1 Cyp4BN13v1 and Cyp4BN15, were highly expressed in cyhalothrin-treated larvae. These CYPs are the candidates that are involved in cyhalothrin detoxification. PMID:24267698

  16. Identification of cytochrome P450 monooxygenase genes and their expression profiles in cyhalothrin-treated Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Shi, Xiao-Qin; Kong, Ye; Zhou, Li-Tao; Guo, Wen-Chao; Ahmat, Tursun; Li, Guo-Qing

    2013-11-01

    Based on a Leptinotarsa decemlineata transcriptome dataset and the GenBank sequences, a total of 74 cytochrome P450 monooxygenase genes (Cyps) were identified. These genes fell into CYP2 clan, mitochondrial clan, CYP3 clan and CYP4 clan, and were classified into 19 families and 35 subfamilies according to standard nomenclature. Two new families were discovered in CYP4 clan, and were named CYP412 and CYP413 respectively. Four new families that were recently discovered in Tribolium castaneum, including mitochondrial family CYP353, CYP3 clan families CYP345 and CYP347, and CYP4 clan family CYP350, were also found in L. decemlineata. The phylogenetic trees of CYPs from L. decemlineata and other representative insect species were constructed, and these trees provided evolutionary insight for the genetic distance. Our results facilitate further researches to understand the functions and evolution of L. decemlineata Cyp genes. In order to find cyhalothrin-inducible Cyp genes, the expression levels of Cyps belonging to CYP12, CYP6, CYP9 and CYP4 families were determined by quantitative reverse transcriptase-PCR in cyhalothrin-treated and control fourth-instar larvae. Nine Cyp genes, i.e., Cyp12H2, Cyp6BH2, Cyp6BJ1, Cyp6BQ17, Cyp6EG1, Cyp6EH1, Cyp6EJ1 Cyp4BN13v1 and Cyp4BN15, were highly expressed in cyhalothrin-treated larvae. These CYPs are the candidates that are involved in cyhalothrin detoxification.

  17. EFFECTS OF SOME BIOINSECTICIDES AND ENTOMOPATHOGENIC FUNGI ON COLORADO POTATO BEETLE (LEPTINOTARSA DECEMLINEATA L.).

    PubMed

    Öztürk, H E; Güven, Ö; Karaca, I

    2015-01-01

    In this study, biological activity of entomopathogenic fungi (4 strains) isolated from the Colorado potato beetle and the commercial biopesticides containing entomopathogenic fungi; Priority® (Paecilomyces fumosoroseus), Nibortem® (Verticillium lecanii), Nostalgist® (Beauveria bassiana), Bio-Magic* (Metarhizium anisopliae), Bio-Nematon* (Paeciliomyces sp.) and plant extracts; Nimbedicine EC* (Azadiractin) were determined against Leptinotarsa decemlineata under laboratory conditions. An Imidacloprid active ingredient commercial insecticide was also used to compare the insecticidal activity and distilled water was used as control. The biological control agents were applied to 2nd-3rd larval instars, 4th larval instars and adults with spray and leaf dipping methods. Single concentration (10⁸ conidia/mL⁻¹) of entomopathogenic fungi and recommended dose of bioinsecticides were prepared for application. The number of dead insects were determined at 3, 5, and 7 days after applications. Experiments were conducted at 25 ±1° C and 60% ± 5 relative humidity with 16:8 h light: dark conditions. Entomopathogenic fungi and bioinsecticides were found to be more effective on larval stage than 4th larval instars and adults. In spray methods, Bio-Magic®, Nibortem®, and Nostalgist® caused 96.4%, 92.9% and 82.1% mortality on 2nd larval instars and 20%, 36.7% and 33.3% mortality on adults, respectively. All local fungal isolates (B. bassiana) applied on 2nd and 4th larval instars caused 100% mortality. Adults showed 58.6-86.2% mortality. PMID:27145587

  18. EFFECTS OF SOME BIOINSECTICIDES AND ENTOMOPATHOGENIC FUNGI ON COLORADO POTATO BEETLE (LEPTINOTARSA DECEMLINEATA L.).

    PubMed

    Öztürk, H E; Güven, Ö; Karaca, I

    2015-01-01

    In this study, biological activity of entomopathogenic fungi (4 strains) isolated from the Colorado potato beetle and the commercial biopesticides containing entomopathogenic fungi; Priority® (Paecilomyces fumosoroseus), Nibortem® (Verticillium lecanii), Nostalgist® (Beauveria bassiana), Bio-Magic* (Metarhizium anisopliae), Bio-Nematon* (Paeciliomyces sp.) and plant extracts; Nimbedicine EC* (Azadiractin) were determined against Leptinotarsa decemlineata under laboratory conditions. An Imidacloprid active ingredient commercial insecticide was also used to compare the insecticidal activity and distilled water was used as control. The biological control agents were applied to 2nd-3rd larval instars, 4th larval instars and adults with spray and leaf dipping methods. Single concentration (10⁸ conidia/mL⁻¹) of entomopathogenic fungi and recommended dose of bioinsecticides were prepared for application. The number of dead insects were determined at 3, 5, and 7 days after applications. Experiments were conducted at 25 ±1° C and 60% ± 5 relative humidity with 16:8 h light: dark conditions. Entomopathogenic fungi and bioinsecticides were found to be more effective on larval stage than 4th larval instars and adults. In spray methods, Bio-Magic®, Nibortem®, and Nostalgist® caused 96.4%, 92.9% and 82.1% mortality on 2nd larval instars and 20%, 36.7% and 33.3% mortality on adults, respectively. All local fungal isolates (B. bassiana) applied on 2nd and 4th larval instars caused 100% mortality. Adults showed 58.6-86.2% mortality.

  19. Chlorantraniliprole susceptibility in Leptinotarsa decemlineata in the north Xinjiang Uygur autonomous region in China.

    PubMed

    Jiang, Wei-Hua; Lu, Wei-Ping; Guo, Wen-Chao; Xia, Zhen-Han; Fu, Wen-Jun; Li, Guo-Qing

    2012-04-01

    The Colorado potato beetle (Leptinotarsa decemlineata (Say)) in the north Xinjiang Uygur autonomous region has evolved resistance to various types of insecticides. Chlorantraniliprole is a novel anthranilic diamide insecticide that binds and activates ryanodine receptors. It exhibited excellent efficacy against L. decemlineata in several field trails in Europe. In the present paper, the susceptibility of L. decemlineata fourth-instar larvae derived from six field populations and L. decemlineata adults derived from three field populations to chlorantraniliprole was determined by a topical application. The fourth-instar larvae were substantially more susceptible to chlorantraniliprole than adults, although the range of susceptibility was far greater among the fourth-instar larvae. Regarding stomach toxicities, adult beetles were less susceptible to chlorantraniliprole than larvae. Chlorantraniliprole was most toxic to second-instar larvae, followed by third- and fourth-instar larvae. These data suggested that the appropriate timing for chlorantraniliprole spraying is the early larval stage. Moreover, the synergistic activities of chlorantraniliprole in combination with triphenyl phosphate, diethyl maleate, or piperonyl butoxide against fourth-instar larvae from two field populations and adults from one field population were tested. Piperonyl butoxide had synergistic effects with chlorantraniliprole against fourth-instar larvae but not against adult beetles. Conversely, triphenyl phosphate and diethyl maleate exerted little synergistic effects. It appears that there is a potential risk of resistance against chlorantraniliprole resulting from cytochrome P450 monooxygenase activity. PMID:22606826

  20. Characterization of gene expression patterns during the initiation and maintenance phases of diapause in the Colorado potato beetle, Leptinotarsa decemlineata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using differential display, 55 putative, diapause-regulated transcripts were isolated from the Colorado potato beetle, Leptinotarsa decemlineata (Say). The insert sizes of the clones ranged from 114 to 795 bp. Fourteen of the transcripts were confirmed by northern blot analysis to be diapause regula...

  1. Down Regulation of Gene Expression Between the Diapause Initiation and Maintenance Phases of the Colorado Potato Beetle, Leptinotarsa Decemlineata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diapause initiation and maintenance phases of the Colorado potato beetle, Leptinotarsa decemlineata were screened. Eight transcripts were found to be down regulated as the beetles enter the diapause maintenance phase of diapause development after day 15 postemergence. These transcripts were also...

  2. A comparison of internal and external lipids of nondiapausing and diapause initiation phase adult Colorado potato beetles, Leptinotarsa decemlineata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Colorado potato beetle, Leptinotarsa decemlineata, reared under diapause inducing conditions will emerge from the soil as an adult and enter the diapause initiation phase, a period where metabolic reserves are stockpiled before the beetles enter the nonfeeding diapause maintenance phase. Interna...

  3. Molecular cloning and characterization of a putative proline dehydrogenase gene in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Lü, Dong; Guo, Wen-Chao; Ahmat, Tursun; Yang, Lu; Mu, Li-Li; Li, Guo-Qing

    2014-04-01

    Leptinotarsa decemlineata adults exhibit a season-dependent activity. In spring, post-diapause beetles often fly a long distance from overwintering sites to potato fields. In summer and autumn, the flight ability is sharply reduced. Proline is the main energy substrate of L. decemlineata during flight and proline dehydrogenase (ProDH) catalyzes the first step in proline catabolism. Here we identified a putative LdProDH gene; it had three cDNA isoforms which shared the same 5'UTR and coding region, but differed in the lengths of 3'UTRs (515, 1 092 and 1 242 bp for isoforms-1, -2 and -3, respectively). LdProDH encoded a 616 amino acid protein that showed high sequence similarity to ProDH-like proteins from other insect species. LdProDH was expressed in the third and fourth instars larvae and adults, but not in pupae. Dietary ingestion of bacterially expressed LdProDH-dsRNA by adults significantly decreased its messenger RNA (mRNA) level, and caused an elevation of free proline content in the hemolymph. Further observation revealed that three canonical polyadenylation signals (AATAAA) were tandemly located in the 3'UTR of isoform-3. The first, second and third polyadenylation sites gave rise to isoforms-1, -2 and -3, respectively. Analysis of the genomic DNA uncovered that the three isoforms resulted from alternative polyadenylation. The mRNA level of isoform-1, which expressed at low levels in pre-diapause adults, became abundant in post-diapause beetles. It is indicated that the LdProDH expression is fine-tuned through 3'UTR to control proline catabolism for the season-dependent activity of L. decemlineata adults. PMID:23956209

  4. Involvement of a putative allatostatin in regulation of juvenile hormone titer and the larval development in Leptinotarsa decemlineata (Say).

    PubMed

    Meng, Qing-Wei; Liu, Xin-Ping; Lü, Feng-Gong; Fu, Kai-Yun; Guo, Wen-Chao; Li, Guo-Qing

    2015-01-01

    Juvenile hormone III (JH III) plays primary roles in regulation of metamorphosis, reproduction and diapause in Leptinotarsa decemlineata, a notorious defoliator of potato. The neurosecretory cell-borne substance(s) negatively affects the final two steps in JH biosynthesis, catalyzed respectively by an epoxidase CYP15A1 and a juvenile hormone acid methyltransferase (JHAMT). In a few insect species other than L. decemlineata, the inhibitory substance is allatostatin (AS) neuropeptide. In this study, two putative AS genes encoding LdAS-C and LdAS-B precursors were cloned. Both LdAS-C and LdAS-B were expressed in the egg, larvae, pupae and adults, and highly expressed in the brain and the gut. Dietary introduction of double-stranded RNAs (dsRNAs) targeting LdAS-C and LdAS-B successfully knocked down respective target genes. Ingestion during 3 and 6 consecutive days of dsLdAS-C significantly increased the LdJHAMT mRNA levels by 3.8 and 9.9 fold respectively. In contrast, ingestion of dsLdAS-B only slightly increased the LdJHAMT expression level by 1.1 and 1.7 fold. Moreover, after one, two and three days' ingestion of dsLdAS-C, the relative JH levels in the hemolymph of treated larvae were 2.5, 4.2 and 1.9 fold higher than those in control beetles. Furthermore, ingestion of dsLdAS-C and dsLdAS-B significantly affected larval growth and delayed larval development. Thus, we provide a line of experimental evidence in L. decemlineata to support the concept that AS-C acts as an allatostatin and inhibit JH biosynthesis. PMID:25452193

  5. Molecular cloning and characterization of a putative proline dehydrogenase gene in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Lü, Dong; Guo, Wen-Chao; Ahmat, Tursun; Yang, Lu; Mu, Li-Li; Li, Guo-Qing

    2014-04-01

    Leptinotarsa decemlineata adults exhibit a season-dependent activity. In spring, post-diapause beetles often fly a long distance from overwintering sites to potato fields. In summer and autumn, the flight ability is sharply reduced. Proline is the main energy substrate of L. decemlineata during flight and proline dehydrogenase (ProDH) catalyzes the first step in proline catabolism. Here we identified a putative LdProDH gene; it had three cDNA isoforms which shared the same 5'UTR and coding region, but differed in the lengths of 3'UTRs (515, 1 092 and 1 242 bp for isoforms-1, -2 and -3, respectively). LdProDH encoded a 616 amino acid protein that showed high sequence similarity to ProDH-like proteins from other insect species. LdProDH was expressed in the third and fourth instars larvae and adults, but not in pupae. Dietary ingestion of bacterially expressed LdProDH-dsRNA by adults significantly decreased its messenger RNA (mRNA) level, and caused an elevation of free proline content in the hemolymph. Further observation revealed that three canonical polyadenylation signals (AATAAA) were tandemly located in the 3'UTR of isoform-3. The first, second and third polyadenylation sites gave rise to isoforms-1, -2 and -3, respectively. Analysis of the genomic DNA uncovered that the three isoforms resulted from alternative polyadenylation. The mRNA level of isoform-1, which expressed at low levels in pre-diapause adults, became abundant in post-diapause beetles. It is indicated that the LdProDH expression is fine-tuned through 3'UTR to control proline catabolism for the season-dependent activity of L. decemlineata adults.

  6. Effects of Potato Cultivars on Some Physiological Processes of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

    PubMed

    Mardani-Talaee, Mozhgan; Zibaee, Arash; Nouri-Ganbalani, Gadir; Rahimi, Vahid; Tajmiri, Pejman

    2015-10-01

    Colorado potato beetle, Leptinotarsa decemlineata (Say), is an important pest of potato throughout the world. Here, the effects of six potato cultivars including 'Arinda,' 'Sprit,' 'Markiez,' 'Lotta,' 'Santae,' and 'Agria' were studied on nutritional indices, digestive enzymes, and some components involved in intermediary metabolism of L. decemlineata. Nutritional indices of the larvae and the adults were significantly different followed by feeding on various potato cultivars. The individuals fed on Agria showed the highest activity of digestive proteases although cathepsin B demonstrated same Activity on Santae and Lotta. The highest activity of α-amylase was found in the larvae fed on Arinda, but the adults demonstrated the highest amylolytic activities on Santae and Agria. Both larvae and adults of L. decemlineata fed on Santae revealed the highest α- and β-glucosidase activities. No significant differences were found in lipase activity of larvae, but the highest lipase activity was found in the adults fed on Santae. The highest activities of transaminases were found in the larvae and adults fed on the Agria except for γ-glutamyl transferase. In case of aldolase, the highest activities were observed in the larvae and adults fed on Santae and Sprit. The highest activities of lactate dehydrogenase were obtained in the larvae and adults fed on Santae. The highest amount of low-density lipophorin was measured in both individuals fed on Santae. There were no significant differences in high-density lipophorin amount of adults, but the highest value was found in the larvae fed on Agria. The lowest amounts of protein and triglyceride were observed in both individuals fed on Santae and Agria, respectively. These results revealed Santae is the most suitable cultivar for L. decemlineata based on digestion and intermediary metabolism findings, but Lotta is an unsuitable cultivar and could be considered for integrated pest management. PMID:26453726

  7. The P450 enzyme Shade mediates the hydroxylation of ecdysone to 20-hydroxyecdysone in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Kong, Y; Liu, X-P; Wan, P-J; Shi, X-Q; Guo, W-C; Li, G-Q

    2014-10-01

    Ecdysone 20-monooxygenase (E20MO), a cytochrome P450 monooxygenase (CYP314A1), catalyses the conversion of ecdysone (E) to 20-hydroxyecdysone (20E). We report here the cloning and characterization of the Halloween gene Shade (Shd) encoding E20MO in the Colorado potato beetle, Leptinotarsa decemlineata. LdSHD has five conserved motifs typical of insect P450s, ie the Helix-C, Helix-I, Helix-K, PxxFxPE/DRF (PERF) and heme-binding motifs. LdShd was expressed in developing eggs, the first to fourth instars, wandering larvae, pupae and adults, with statistically significant fluctuations. Its mRNA was ubiquitously distributed in the head, thorax and abdomen. The recombinant LdSHD protein expressed in Spodoptera frugiperda 9 (Sf9) cells catalysed the conversion of E to 20E. Dietary introduction of double-stranded RNA (dsRNA) of LdShd into the second instar larvae successfully knocked down the LdShd expression level, decreased the mRNA level of the ecdysone receptor (LdEcR) gene, caused larval lethality, delayed development and affected pupation. Moreover, ingestion of LdShd-dsRNA by the fourth instars also down-regulated LdShd and LdEcR expression, reduced the 20E titre, and negatively influenced pupation. Introduction of 20E and a nonsteroidal ecdysteroid agonist halofenozide into the LdShd-dsRNA-ingested second instars, and of halofenozide into the LdShd-dsRNA-ingested fourth instars almost completely relieved the negative effects on larval performance. Thus, LdSHD functions to regulate metamorphotic processes by converting E to 20E in a coleopteran insect species Le. decemlineata. PMID:24989229

  8. A putative Δ1-pyrroline-5-carboxylate synthetase involved in the biosynthesis of proline and arginine in Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Fu, Kai-Yun; Lü, Feng-Gong; Guo, Wen-Chao; Li, Guo-Qing

    2014-12-01

    Delta 1-pyrroline-5-carboxylate synthetase (P5CS) catalyzes the conversion of glutamate (Glu) to Glu semialdehyde (GSA). GSA spontaneously cyclizes to form P5C. P5C is then reduced to proline (Pro) or is converted to ornithine, the intermediate for arginine (Arg) biosynthesis. In the present study, a full-length Ldp5cs complementary DNA was cloned from the Colorado potato beetle Leptinotarsa decemlineata, a notorious insect defoliator of potato in most potato-growing regions of the world. Ldp5cs encodes a 792-amino-acid protein which shares high identity to homologues from other insect species. Quantitative reverse transcription polymerase chain reaction revealed that Ldp5cs was ubiquitously expressed in the eggs, first to fourth-instar larvae, wandering larvae, pupae and sexually mature adults. In the adults, Ldp5cs mRNA levels were higher in the fat body, foregut, midgut and hindgut, moderate in the ventral ganglion, lower in the thorax muscles, epidermis and Malpighian tubules. Two double-stranded RNAs (dsRNAs) (dsLdp5cs1 and dsLdp5cs2) targeting Ldp5cs were constructed and bacterially expressed. Ingestion during 3 consecutive days of dsLdp5cs1 or dsLdp5cs2 successfully silenced Ldp5cs, significantly reduced the contents of Pro and Arg in the hemolymph, decreased flight speed and shortened flight distance of the resulting adults. Furthermore, knocking down Ldp5cs significantly increased adult mortality. Thus, our results suggest that identified Ldp5cs encodes a functional P5CS enzyme that is involved in the biosynthesis of Pro and Arg in L. decemlineata. PMID:25450565

  9. The P450 enzyme Shade mediates the hydroxylation of ecdysone to 20-hydroxyecdysone in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Kong, Y; Liu, X-P; Wan, P-J; Shi, X-Q; Guo, W-C; Li, G-Q

    2014-10-01

    Ecdysone 20-monooxygenase (E20MO), a cytochrome P450 monooxygenase (CYP314A1), catalyses the conversion of ecdysone (E) to 20-hydroxyecdysone (20E). We report here the cloning and characterization of the Halloween gene Shade (Shd) encoding E20MO in the Colorado potato beetle, Leptinotarsa decemlineata. LdSHD has five conserved motifs typical of insect P450s, ie the Helix-C, Helix-I, Helix-K, PxxFxPE/DRF (PERF) and heme-binding motifs. LdShd was expressed in developing eggs, the first to fourth instars, wandering larvae, pupae and adults, with statistically significant fluctuations. Its mRNA was ubiquitously distributed in the head, thorax and abdomen. The recombinant LdSHD protein expressed in Spodoptera frugiperda 9 (Sf9) cells catalysed the conversion of E to 20E. Dietary introduction of double-stranded RNA (dsRNA) of LdShd into the second instar larvae successfully knocked down the LdShd expression level, decreased the mRNA level of the ecdysone receptor (LdEcR) gene, caused larval lethality, delayed development and affected pupation. Moreover, ingestion of LdShd-dsRNA by the fourth instars also down-regulated LdShd and LdEcR expression, reduced the 20E titre, and negatively influenced pupation. Introduction of 20E and a nonsteroidal ecdysteroid agonist halofenozide into the LdShd-dsRNA-ingested second instars, and of halofenozide into the LdShd-dsRNA-ingested fourth instars almost completely relieved the negative effects on larval performance. Thus, LdSHD functions to regulate metamorphotic processes by converting E to 20E in a coleopteran insect species Le. decemlineata.

  10. Growth and development of Colorado potato beetle larvae, Leptinotarsa decemlineata, on potato plants expressing the oryzacystatin II proteinase inhibitor.

    PubMed

    Cingel, Aleksandar; Savić, Jelena; Vinterhalter, Branka; Vinterhalter, Dragan; Kostić, Miroslav; Jovanović, Darka Šešlija; Smigocki, Ann; Ninković, Slavica

    2015-08-01

    Plant proteinase inhibitors (PIs) are attractive tools for crop improvement and their heterologous expression can enhance insect resistance in transgenic plants. PI oryzacystatin II (OCII), isolated from rice, showed potential in controlling pests that utilize cysteine proteinases for protein digestion. To evaluate the applicability of the OCII gene in enhancing plant defence, OCII-transformed potatoes were bioassayed for resistance to Colorado potato beetle (Leptinotarsa decemlineata Say). Feeding on transformed leaves of potato cultivars Desiree and Jelica significantly affected larval growth and development, but did not change mortality rates. During the L2 and L3 developmental stages larvae consumed the OCII-transformed foliage faster as compared to the nontransformed control. Also these larvae reached the prepupal stage (end of L4 stage) 2 days earlier than those fed on control leaves. However, the total amounts of consumed OCII-transformed leaves were up to 23% lower than of control, and the maximal weights of prepupal larvae were reduced by up to 18% as compared to larvae fed on nontransformed leaves. The reduction in insect fitness reported in this study in combination with other control measures, could lead to improved CPB resistance management in potato. PMID:25820664

  11. Growth and development of Colorado potato beetle larvae, Leptinotarsa decemlineata, on potato plants expressing the oryzacystatin II proteinase inhibitor.

    PubMed

    Cingel, Aleksandar; Savić, Jelena; Vinterhalter, Branka; Vinterhalter, Dragan; Kostić, Miroslav; Jovanović, Darka Šešlija; Smigocki, Ann; Ninković, Slavica

    2015-08-01

    Plant proteinase inhibitors (PIs) are attractive tools for crop improvement and their heterologous expression can enhance insect resistance in transgenic plants. PI oryzacystatin II (OCII), isolated from rice, showed potential in controlling pests that utilize cysteine proteinases for protein digestion. To evaluate the applicability of the OCII gene in enhancing plant defence, OCII-transformed potatoes were bioassayed for resistance to Colorado potato beetle (Leptinotarsa decemlineata Say). Feeding on transformed leaves of potato cultivars Desiree and Jelica significantly affected larval growth and development, but did not change mortality rates. During the L2 and L3 developmental stages larvae consumed the OCII-transformed foliage faster as compared to the nontransformed control. Also these larvae reached the prepupal stage (end of L4 stage) 2 days earlier than those fed on control leaves. However, the total amounts of consumed OCII-transformed leaves were up to 23% lower than of control, and the maximal weights of prepupal larvae were reduced by up to 18% as compared to larvae fed on nontransformed leaves. The reduction in insect fitness reported in this study in combination with other control measures, could lead to improved CPB resistance management in potato.

  12. Resting metabolic rate can vary with age independently from body mass changes in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Piiroinen, Saija; Lindström, Leena; Lyytinen, Anne

    2010-03-01

    Temperature and mass dependency of insect metabolic rates are well known, while less attention has been given to other factors, such as age. Among insect species that experience seasonal variation in environmental conditions, such as in temperate latitudes, age may also have indirect effects on the metabolic rate. We examined the effect of age on the resting metabolic rate of Leptinotarsa decemlineata during 11 days after adult emergence by using flow-through respirometry. Age had a significant mass-independent effect on metabolic rate of beetles. A twofold increase in metabolic rate occurred during the first 2 days of adult life after which metabolic rate decreased with age relatively slowly. Ten day-old adult beetles had a metabolic rate similar to newly emerged beetles. The beetles have to be able to complete their development and prepare for overwintering during the relatively short favourable summer periods. Therefore, the observed pattern in metabolic rate may reflect physiological changes in the pre-diapause beetles adapted to temperate latitudes.

  13. CHARACTERIZATION AND FUNCTIONAL STUDY OF A PUTATIVE JUVENILE HORMONE DIOL KINASE IN THE COLORADO POTATO BEETLE Leptinotarsa decemlineata (Say).

    PubMed

    Fu, Kai-Yun; Lü, Feng-Gong; Guo, Wen-Chao; Li, Guo-Qing

    2015-11-01

    Juvenile hormone diol kinase (JHDK) is an enzyme involved in JH degradation. In the present article, a putative JHDK cDNA (LdJHDK) was cloned from the Colorado potato beetle Leptinotarsa decemlineata. The cDNA consists of 814 bp, containing a 555 bp open reading frame encoding a 184 amino acid protein. LdJHDK reveals a high degree of identity to the previously reported insect JHDKs. It possesses three conserved purine nucleotide-binding elements, and contains three EF-hand motifs (helix-loop-helix structural domains). LdJHDK mRNA was mainly detected in hindgut and Malpighian tubules. Besides, a trace amount of LdJHDK mRNA was also found in thoracic muscles, brain-corpora cardiaca-corpora allata complex, foregut, midgut, ventral ganglia, fat body, epidermis, and hemocytes. Moreover, LdJHDK was expressed throughout all developmental stages. Within the first, second, and third larval instar, the expression levels of LdJHDK were higher just before and right after the molt, and were lower in the intermediate instar. In the fourth larval instar, the highest peak of LdJHDK occurred 56 h after ecdysis. Ingestion of double-stranded RNA (dsRNA) against LdJHDK successfully knocked down the target gene, increased JH titer, and significantly upregulated LdKr-h1 mRNA level. Knockdown of LdJHDK significantly impaired adult emergence. Thus, we provide a line of experimental evidence in L. decemlineata to support that LdJHDK encodes function protein involved in JH degradation. PMID:26280246

  14. CHARACTERIZATION AND FUNCTIONAL STUDY OF A PUTATIVE JUVENILE HORMONE DIOL KINASE IN THE COLORADO POTATO BEETLE Leptinotarsa decemlineata (Say).

    PubMed

    Fu, Kai-Yun; Lü, Feng-Gong; Guo, Wen-Chao; Li, Guo-Qing

    2015-11-01

    Juvenile hormone diol kinase (JHDK) is an enzyme involved in JH degradation. In the present article, a putative JHDK cDNA (LdJHDK) was cloned from the Colorado potato beetle Leptinotarsa decemlineata. The cDNA consists of 814 bp, containing a 555 bp open reading frame encoding a 184 amino acid protein. LdJHDK reveals a high degree of identity to the previously reported insect JHDKs. It possesses three conserved purine nucleotide-binding elements, and contains three EF-hand motifs (helix-loop-helix structural domains). LdJHDK mRNA was mainly detected in hindgut and Malpighian tubules. Besides, a trace amount of LdJHDK mRNA was also found in thoracic muscles, brain-corpora cardiaca-corpora allata complex, foregut, midgut, ventral ganglia, fat body, epidermis, and hemocytes. Moreover, LdJHDK was expressed throughout all developmental stages. Within the first, second, and third larval instar, the expression levels of LdJHDK were higher just before and right after the molt, and were lower in the intermediate instar. In the fourth larval instar, the highest peak of LdJHDK occurred 56 h after ecdysis. Ingestion of double-stranded RNA (dsRNA) against LdJHDK successfully knocked down the target gene, increased JH titer, and significantly upregulated LdKr-h1 mRNA level. Knockdown of LdJHDK significantly impaired adult emergence. Thus, we provide a line of experimental evidence in L. decemlineata to support that LdJHDK encodes function protein involved in JH degradation.

  15. Laboratory Evaluation of Five Chitin Synthesis Inhibitors Against the Colorado Potato Beetle, Leptinotarsa decemlineata

    PubMed Central

    Karimzadeh, R.; Hejazi, M. J.; Rahimzadeh Khoei, F.; Moghaddam, M.

    2007-01-01

    Results of laboratory experiments are reported that tested the effects of five chitin synthesis inhibitors, diflubenzuron, cyromazine, lufenuron, hexaflumuron and triflumuron. on second instars of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Crysomelidae), originally collected from potato fields of Bostanabaad, a town 66 km southeast of Tabriz, Iran. In bioassays, the larvae were fed potato leaves dipped in aqueous solutions containing chitin synthesis inhibitors. The mortalities and abnormalities of the treated larvae were recorded 72 hours after treatments. LC50 values were 58.6, 69.6, 27.3, 0.79 and 81.4 mg ai/ L for diflubenzuron, cyromazine, lufenuron, hexaflumuron and triflumuron, respectively. Compared with phosalone, which is one of the common insecticides used for controlling this pest in Iran, lufenuron and hexaflumuron seem to be much more potent, and if they perform equally well in the field, they would be suitable candidates to be considered as reduced risk insecticides in management programs for L. decemlineata due to much wider margin of safety for mammals and considerably fewer undesirable environmental side effects. PMID:20345285

  16. Laboratory evaluation of five chitin synthesis inhibitors against the colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Karimzadeh, R; Hejazi, M J; Rahimzadeh Khoei, F; Moghaddam, M

    2007-01-01

    Results of laboratory experiments are reported that tested the effects of five chitin synthesis inhibitors, diflubenzuron, cyromazine, lufenuron, hexaflumuron and triflumuron. on second instars of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Crysomelidae), originally collected from potato fields of Bostanabaad, a town 66 km southeast of Tabriz, Iran. In bioassays, the larvae were fed potato leaves dipped in aqueous solutions containing chitin synthesis inhibitors. The mortalities and abnormalities of the treated larvae were recorded 72 hours after treatments. LC(50) values were 58.6, 69.6, 27.3, 0.79 and 81.4 mg ai/ L for diflubenzuron, cyromazine, lufenuron, hexaflumuron and triflumuron, respectively. Compared with phosalone, which is one of the common insecticides used for controlling this pest in Iran, lufenuron and hexaflumuron seem to be much more potent, and if they perform equally well in the field, they would be suitable candidates to be considered as reduced risk insecticides in management programs for L. decemlineata due to much wider margin of safety for mammals and considerably fewer undesirable environmental side effects. PMID:20345285

  17. Dynamic spatial structure in the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae)

    NASA Astrophysics Data System (ADS)

    Blom, Paul Erik

    2001-07-01

    Integrating GPS with visual canopy surveys, a 1-m sampling support was used to explore within-field spatial organization of the Colorado potato beetle, Leptinotarsa decemlineata (Say), in potatoes (Solanum tuberosum (L.)). Georeferenced adult and large larvae counts were made in four ˜1.5 ha untreated potato fields during two seasons. Overwintered, immigrating adults established mean density trends, but spatial dependency (covariance structure) was not detected. Large larvae and F1 adults, in contrast, displayed covariance structure, accounting for up to ˜45% of the variation. Spatial patterns were related to population phenology, density, and mean density trends established during immigration. The stability of these patterns was tested in fields treated with a narrow perimeter (5.5 m) of systemic imidacloprid and in fields where all rows received the systemic. Perimeter treatment reduced mean densities with no effect on phenology. Immigrating adults established similar trends in both treatments, but F1 larval trends of the Perimeter treatments diverged from immigrant patterns. Immigrating adults had little to no spatial dependence (covariance structure), while covariance structure of F1 larval and F1 adult populations developed as density increased in both treatments. Yields increased at a proportion higher than the proportion of land area treated, but remained lower than the Whole-field treatment. Refinement of border width is discussed to optimize trade-offs between yield, quality, and long-term maintenance of susceptibility. To optimize perimeter width, locations of individual L. decemlineata overwintered adults were georeferenced within 24 hours of their immigration into a potato field in two field seasons. Distance was measured to the nearest field edge or to the field edge along a radial vector from the field center. The frequency of beetles captured within 1-m distance intervals was modeled as an exponential decay function of distance from the edge for

  18. Life-history parameters of the Colorado potato beetle, Leptinotarsa decemlineata, on seven commercial cultivars of potato, Solanum tuberosum.

    PubMed

    Fathi, Seyed Ali Asghar; Fakhr-Taha, Zoha; Razmjou, Jabraeil

    2013-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), is an important pest of potato, Solanum tuberosum L. (Solanales: Solanaceae), crops in the Ardabil region of Iran. In this research, the life-history parameters of L. decemlineata were investigated on seven potato cultivars, namely Agria, Aozonia, Diamant, Cosmus, Kondor, Morene, and Savalan, in a greenhouse at 23 ± 1° C and 55 ± 5% RH under a natural photoperiod. The results indicated that the development time of larvae was longest on Savalan (18.3 days) among the tested potato cultivars. The survival rates (egg to adult) on Savalan and Morene were significantly lower than on the other studied cultivars. L. decemlineata reared on Savalan had the lowest fecundity (286.3 eggs/female) among the tested potato cultivars. The oviposition period of females was significantly shorter on Savalan and Diamant than on Kondor, Aozonia, Morene, Agria, and Cosmus. The values of intrinsic rate of natural increase and population growth rate were lowest on Savalan (0.055 and 1.056, respectively). The generation time and doubling time were significantly longest on Savalan (69.5 and 12.7 days, respectively). Based on these results, it can be concluded that Savalan is the least suitable cultivar for L. decemlineata among the ones tested. These results can be useful in integrated management of L. decemlineata in potato fields. PMID:24794138

  19. Identification of carboxylesterase genes and their expression profiles in the Colorado potato beetle Leptinotarsa decemlineata treated with fipronil and cyhalothrin.

    PubMed

    Lü, Feng-Gong; Fu, Kai-Yun; Li, Qian; Guo, Wen-Chao; Ahmat, Tursun; Li, Guo-Qing

    2015-07-01

    Based on the Leptinotarsa decemlineata transcriptome dataset and the GenBank sequences, 70 novel carboxylesterases and 2 acetylcholinesterases were found. The 72 members belong to a multifunctional carboxylesterase/cholinesterase superfamily (CCE). A phylogenetic tree including the 72 LdCCEs and the CCEs from Tribolium castaneum, Drosophila melanogaster and Apis mellifera revealed that all CCEs fell into three main phylogenetic groups: dietary/detoxification, hormone/semiochemical processing, and neurodevelopmental classes. Numbers of L. decemlineata CCEs in the three classes were 52, 12 and 8, respectively. The dietary/detoxification class includes two clades: coleopteran xenobiotic metabolizing and α-esterase type CCEs. CCEs in the two clades have independently expanded in L. decemlineata. The hormone/semiochemical processing class has three clades: integument CCEs, β- and pheromone CCEs and juvenile hormone CCEs. Integument CCEs in L. decemlineata have also expanded. The neurodevelopmental CCEs are implicated the most ancient class, containing acetylcholinesterase, neuroligin, neurotactin, glutactin, gliotactin and others. Among the 70 novel CCE genes, KM220566, KM220530, KM220576, KM220527 and KM220541 were fipronil-inducible, and KM220578, KM220566, KM220542, KM220564, KM220561, KM220554, KM220527, KM220538 and KM220541 were cyhalothrin-inducible. They were the candidates involving in insecticide detoxification. Moreover, our results also provided a platform to understand the functions and evolution of L. decemlineata CCE genes. PMID:26071812

  20. Identification of carboxylesterase genes and their expression profiles in the Colorado potato beetle Leptinotarsa decemlineata treated with fipronil and cyhalothrin.

    PubMed

    Lü, Feng-Gong; Fu, Kai-Yun; Li, Qian; Guo, Wen-Chao; Ahmat, Tursun; Li, Guo-Qing

    2015-07-01

    Based on the Leptinotarsa decemlineata transcriptome dataset and the GenBank sequences, 70 novel carboxylesterases and 2 acetylcholinesterases were found. The 72 members belong to a multifunctional carboxylesterase/cholinesterase superfamily (CCE). A phylogenetic tree including the 72 LdCCEs and the CCEs from Tribolium castaneum, Drosophila melanogaster and Apis mellifera revealed that all CCEs fell into three main phylogenetic groups: dietary/detoxification, hormone/semiochemical processing, and neurodevelopmental classes. Numbers of L. decemlineata CCEs in the three classes were 52, 12 and 8, respectively. The dietary/detoxification class includes two clades: coleopteran xenobiotic metabolizing and α-esterase type CCEs. CCEs in the two clades have independently expanded in L. decemlineata. The hormone/semiochemical processing class has three clades: integument CCEs, β- and pheromone CCEs and juvenile hormone CCEs. Integument CCEs in L. decemlineata have also expanded. The neurodevelopmental CCEs are implicated the most ancient class, containing acetylcholinesterase, neuroligin, neurotactin, glutactin, gliotactin and others. Among the 70 novel CCE genes, KM220566, KM220530, KM220576, KM220527 and KM220541 were fipronil-inducible, and KM220578, KM220566, KM220542, KM220564, KM220561, KM220554, KM220527, KM220538 and KM220541 were cyhalothrin-inducible. They were the candidates involving in insecticide detoxification. Moreover, our results also provided a platform to understand the functions and evolution of L. decemlineata CCE genes.

  1. Life-history parameters of the Colorado potato beetle, Leptinotarsa decemlineata, on seven commercial cultivars of potato, Solanum tuberosum.

    PubMed

    Fathi, Seyed Ali Asghar; Fakhr-Taha, Zoha; Razmjou, Jabraeil

    2013-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), is an important pest of potato, Solanum tuberosum L. (Solanales: Solanaceae), crops in the Ardabil region of Iran. In this research, the life-history parameters of L. decemlineata were investigated on seven potato cultivars, namely Agria, Aozonia, Diamant, Cosmus, Kondor, Morene, and Savalan, in a greenhouse at 23 ± 1° C and 55 ± 5% RH under a natural photoperiod. The results indicated that the development time of larvae was longest on Savalan (18.3 days) among the tested potato cultivars. The survival rates (egg to adult) on Savalan and Morene were significantly lower than on the other studied cultivars. L. decemlineata reared on Savalan had the lowest fecundity (286.3 eggs/female) among the tested potato cultivars. The oviposition period of females was significantly shorter on Savalan and Diamant than on Kondor, Aozonia, Morene, Agria, and Cosmus. The values of intrinsic rate of natural increase and population growth rate were lowest on Savalan (0.055 and 1.056, respectively). The generation time and doubling time were significantly longest on Savalan (69.5 and 12.7 days, respectively). Based on these results, it can be concluded that Savalan is the least suitable cultivar for L. decemlineata among the ones tested. These results can be useful in integrated management of L. decemlineata in potato fields.

  2. Insecticidal metabolites from the rhizomes of Veratrum album against adults of Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Aydin, Tuba; Cakir, Ahmet; Kazaz, Cavit; Bayrak, Neslihan; Bayir, Yasin; Taşkesenligil, Yavuz

    2014-08-01

    The dried rhizomes of Veratrum album were individually extracted with CHCl3 , acetone, and NH4 OH/benzene to test the toxic effects against the Colorado potato beetle, Leptinotarsa decemlineata, which is an important agricultural pest. Fifteen compounds in various amounts were isolated from the extracts using column and thin-layer chromatography. The chemical structures of 14 compounds were characterized as octacosan-1-ol (1), β-sitosterol (2), stearic acid (3), diosgenin (4), resveratrol (5), wittifuran X (6), oxyresveratrol (7), β-sitosterol 3-O-β-D-glucopyranoside (8), diosgenin 3-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyronoside (9), oxyresveratrol 3-O-β-D-glucopyranoside (10), jervine (11), pseudojervine (13), 5,6-dihydro-1-hydroxyjervine (14), and saccharose (15) using UV, IR, MS, (1) H- and (13)C-NMR, and 2D-NMR spectroscopic methods. However, the chemical structure of 12, an oligosaccharide, has not fully been elucidated. Compounds 4, 6, 9, and 10 were isolated from V. album rhizomes for the first time in the current study. The toxic effects of three extracts (acetone, CHCl3 , and NH4 OH/benzene) and six metabolites, 2, 2+4, 5, 7, 8, and 11, were evaluated against the Colorado potato beetle. The assay revealed that all three extracts, and compounds 7, 8, and 11 exhibited potent toxic effects against this pest. This is the first report on the evaluation of the toxic effects of the extracts and secondary metabolites of V. album rhizomes against L. decemlineata. Based on these results, it can be concluded that the extracts can be used as natural insecticides. PMID:25146763

  3. IDENTIFICATION AND HORMONE INDUCTION OF PUTATIVE CHITIN SYNTHASE GENES AND SPLICE VARIANTS IN Leptinotarsa decemlineata (SAY).

    PubMed

    Shi, Ji-Feng; Mu, Li-Li; Guo, Wen-Chao; Li, Guo-Qing

    2016-08-01

    Chitin synthase (ChS) plays a critical role in chitin synthesis and excretion. In this study, two ChS genes (LdChSA and LdChSB) were identified in Leptinotarsa decemlineata. LdChSA contains two splicing variants, LdChSAa and LdChSAb. Within the first, second, and third larval instars, the mRNA levels of LdChSAa, LdChSAb, and LdChSB coincide with the peaks of circulating 20-hydroxyecdysone (20E) and juvenile hormone (JH). In vitro culture of midguts and an in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide stimulated the expression of the three LdChSs. Conversely, a reduction of 20E by RNA interference (RNAi) of an ecdysteroidogenesis gene LdSHD repressed the expression of these LdChSs, and ingestion of halofenozide by LdSHD RNAi larvae rescued the repression. Moreover, disruption of 20E signaling by RNAi of LdEcR, LdE75, LdHR3, and LdFTZ-F1 reduced the expression levels of these genes. Similarly, in vitro culture and an in vivo bioassay showed that exogenous JH and a JH analog methoprene activated the expression of the three LdChSs, whereas a decrease in JH by RNAi of a JH biosynthesis gene LdJHAMT downregulated these LdChSs. It seems that JH upregulates LdChSs at the early stage of each instar, whereas a 20E pulse triggers the transcription of LdChSs during molting in L. decemlineata. PMID:27030662

  4. Insecticidal metabolites from the rhizomes of Veratrum album against adults of Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Aydin, Tuba; Cakir, Ahmet; Kazaz, Cavit; Bayrak, Neslihan; Bayir, Yasin; Taşkesenligil, Yavuz

    2014-08-01

    The dried rhizomes of Veratrum album were individually extracted with CHCl3 , acetone, and NH4 OH/benzene to test the toxic effects against the Colorado potato beetle, Leptinotarsa decemlineata, which is an important agricultural pest. Fifteen compounds in various amounts were isolated from the extracts using column and thin-layer chromatography. The chemical structures of 14 compounds were characterized as octacosan-1-ol (1), β-sitosterol (2), stearic acid (3), diosgenin (4), resveratrol (5), wittifuran X (6), oxyresveratrol (7), β-sitosterol 3-O-β-D-glucopyranoside (8), diosgenin 3-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyronoside (9), oxyresveratrol 3-O-β-D-glucopyranoside (10), jervine (11), pseudojervine (13), 5,6-dihydro-1-hydroxyjervine (14), and saccharose (15) using UV, IR, MS, (1) H- and (13)C-NMR, and 2D-NMR spectroscopic methods. However, the chemical structure of 12, an oligosaccharide, has not fully been elucidated. Compounds 4, 6, 9, and 10 were isolated from V. album rhizomes for the first time in the current study. The toxic effects of three extracts (acetone, CHCl3 , and NH4 OH/benzene) and six metabolites, 2, 2+4, 5, 7, 8, and 11, were evaluated against the Colorado potato beetle. The assay revealed that all three extracts, and compounds 7, 8, and 11 exhibited potent toxic effects against this pest. This is the first report on the evaluation of the toxic effects of the extracts and secondary metabolites of V. album rhizomes against L. decemlineata. Based on these results, it can be concluded that the extracts can be used as natural insecticides.

  5. [An increase in the immune system activity of the wax moth Galleria mellonella and of the Colorado potato beetle Leptinotarsa decemlineata under effect of organophosphorus insecticide].

    PubMed

    2013-01-01

    There has been performed evaluation of the effect of the organophosphorus insecticide (pirimifos-methyl) on some components of the insect immune response. The cellular (a change of the number of hemocytes and of intensity of incapsulation) and the humoral (a change of phenoloxidase activity) components of the immune response were studied in larvae of representatives of two orders--the Colorado potato beetle (Leptinotarsa decemlineata, Chrysomelidae, Coleoptera) and the wax moth (Galeriia mellonella, Pyralidae, Lepidoptera). The action of the insecticide has been found to lead to stimulation of immune reactions (an increase of phenoloxidase activities and of intensity of incapsulation, a rise of the number of hemocytes) at the contact treatment of both sublethal and the half-lethal doses of pirimifos-methyl. PMID:25509049

  6. [An increase in the immune system activity of the wax moth Galleria mellonella and of the Colorado potato beetle Leptinotarsa decemlineata under effect of organophosphorus insecticide].

    PubMed

    Dubovskiy, I M; Yaroslavtseva, O N; Kryukov, V Yu; Benkovskaya, G V; Glupov, V V

    2013-01-01

    There has been performed evaluation of the effect of the organophosphorus insecticide (pirimifos-methyl) on some components of the insect immune response. The cellular (a change of the number of hemocytes and of intensity of incapsulation) and the humoral (a change of phenoloxidase activity) components of the immune response were studied in larvae of representatives of two orders--the Colorado potato beetle (Leptinotarsa decemlineata, Chrysomelidae, Coleoptera) and the wax moth (Galeriia mellonella, Pyralidae, Lepidoptera). The action of the insecticide has been found to lead to stimulation of immune reactions (an increase of phenoloxidase activities and of intensity of incapsulation, a rise of the number of hemocytes) at the contact treatment of both sublethal and the half-lethal doses of pirimifos-methyl. PMID:25490848

  7. [An increase in the immune system activity of the wax moth Galleria mellonella and of the Colorado potato beetle Leptinotarsa decemlineata under effect of organophosphorus insecticide].

    PubMed

    Dubovskiy, I M; Yaroslavtseva, O N; Kryukov, V Yu; Benkovskaya, G V; Glupov, V V

    2013-01-01

    There has been performed evaluation of the effect of the organophosphorus insecticide (pirimifos-methyl) on some components of the insect immune response. The cellular (a change of the number of hemocytes and of intensity of incapsulation) and the humoral (a change of phenoloxidase activity) components of the immune response were studied in larvae of representatives of two orders--the Colorado potato beetle (Leptinotarsa decemlineata, Chrysomelidae, Coleoptera) and the wax moth (Galeriia mellonella, Pyralidae, Lepidoptera). The action of the insecticide has been found to lead to stimulation of immune reactions (an increase of phenoloxidase activities and of intensity of incapsulation, a rise of the number of hemocytes) at the contact treatment of both sublethal and the half-lethal doses of pirimifos-methyl.

  8. Effect of insecticide management history on emergence phenology and neonicotinoid resistance in Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

    PubMed

    Huseth, A S; Groves, R L

    2013-12-01

    Emergence phenology and fitness attributes of several Colorado potato beetle, Leptinotarsa decemlineata (Say), populations were measured under field and greenhouse conditions. Anecdotal observations by producers and pest managers in many locations of the upper Midwest increasingly suggested that select populations of Colorado potato beetle were emerging over a longer period in the spring and were less sensitive to systemic neonicotinoids in cultivated potato. These changes in emergence phenology may be related to changes in systemic insecticide concentration over time. Specifically, a prolonged period of adult emergence in the spring increases the potential of low-dose chronic exposure to systemic neonicotinoid insecticides in potato. In 2010 and 2011, our objectives were twofold: 1) establish a common garden experiment to compare the emergence phenology of Colorado potato beetle populations uniquely managed with variable insecticide inputs, and 2) measure postdormancy fitness of emerged adult beetles from among these selected populations. Cumulative adult emergence was modeled with logistic regression. Results from this study found no clear evidence for direct relationships between phenology and management history or resistance. Differences in reproductive capacity, sex ratio, and body size were apparent in some instances. However, these results did not uniformly correspond to one specific form of potato pest management tested here. In this study, long-term reliance on systemic insecticides for Colorado potato beetle control did not serve as a strong predictor for variable life history for selected populations in Wisconsin. PMID:24498751

  9. Genetic relationships of introduced Colorado potato beetle Leptinotarsa decemlineata populations in Xinjiang, China.

    PubMed

    Zhang, Jing-Jie; Yang, Juan; Li, Ying-Chao; Liu, Ning; Zhang, Run-Zhi

    2013-10-01

    The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is an infamous invasive species worldwide that aggressively attacks potato and other Solanaceae crops. CPB was first found in China in 1993 and has since spread across 2.77 × 10(5) km(2) in Xinjiang Uygur Autonomous Region. To better understand genetic variation and migration patterns, we used seven polymorphic microsatellite loci to elucidate the genetic relationships and gene flow among 10 CPB populations across Xinjiang. (i) Overall low levels of genetic diversity were detected on the entire population in Xinjiang but most of the diversity was retained among populations during invasion. (ii) The mean pairwise FST was low (0.071 ± 0.043) among populations. The genetic differentiation was little (pairwise FST 0.038 ± 0.016) between the five interior populations (Wusu, Urumqi, Jimsar, Qitai and Mulei) and Tacheng population. The six populations might come from the same genetic group via Bayesian clustering and were closely related on a neighbor-joining tree. Combining the history data, the five interior populations may have originated from Tacheng. (iii) Gene flow was frequent, especially among the five interior populations. Individuals from the interior populations could be assigned to Tacheng at higher probabilities (means 0.518 ± 0.127) than vice versa (means 0.328 ± 0.074), suggesting that the beetle population has spread from the border to the interior in Xinjiang. PMID:23955877

  10. Effect of insecticide management history on emergence phenology and neonicotinoid resistance in Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

    PubMed

    Huseth, A S; Groves, R L

    2013-12-01

    Emergence phenology and fitness attributes of several Colorado potato beetle, Leptinotarsa decemlineata (Say), populations were measured under field and greenhouse conditions. Anecdotal observations by producers and pest managers in many locations of the upper Midwest increasingly suggested that select populations of Colorado potato beetle were emerging over a longer period in the spring and were less sensitive to systemic neonicotinoids in cultivated potato. These changes in emergence phenology may be related to changes in systemic insecticide concentration over time. Specifically, a prolonged period of adult emergence in the spring increases the potential of low-dose chronic exposure to systemic neonicotinoid insecticides in potato. In 2010 and 2011, our objectives were twofold: 1) establish a common garden experiment to compare the emergence phenology of Colorado potato beetle populations uniquely managed with variable insecticide inputs, and 2) measure postdormancy fitness of emerged adult beetles from among these selected populations. Cumulative adult emergence was modeled with logistic regression. Results from this study found no clear evidence for direct relationships between phenology and management history or resistance. Differences in reproductive capacity, sex ratio, and body size were apparent in some instances. However, these results did not uniformly correspond to one specific form of potato pest management tested here. In this study, long-term reliance on systemic insecticides for Colorado potato beetle control did not serve as a strong predictor for variable life history for selected populations in Wisconsin.

  11. Studies of two naturally occurring compounds which effect release of acetylcholine from synaptosomes. [Leptinotarsa decemlineata

    SciTech Connect

    Koenig, M.L.

    1985-01-01

    Two naturally occurring compounds which effect the release of neurotransmitter from synaptosomes have been purified to apparent homogeneity. Iotrochotin (IOT) isolated from wound exudate of the Caribbean purple bleeder sponge promotes release in a manner that is independent of the extracellular Ca/sup 2 +/ ion concentration. Leptinotarsin (LPT-d), a protein taken from hemolymph of the Colorado potato beetle, Leptinotarsa decemlineata, stimulates Ca/sup 2 +/-dependent release. IOT is slightly acidic and has a molecular weight of approximately 18 kD. (/sup 3/H)acetylcholine which has been introduced into synaptosomes as (/sup 3/H)choline can be released by IOT. The toxin releasable pool of labelled neurotransmitter is not depleted by depolarization of the synaptosomes with high potassium, and therefore seems to be primarily extravesicular. LPT-d is a larger protein (molecular weight = 45 kD) than IOT, and seems to effect primarily vesicular release by opening at least one type of presynaptic Ca/sup 2 +/ channel. The facilitatory effects of the toxin on synaptosomal release can be inhibited by inorganic Ca/sup 2 +/ channel antagonists, but are not generally affected by organic antagonists.

  12. Genetic relationships of introduced Colorado potato beetle Leptinotarsa decemlineata populations in Xinjiang, China.

    PubMed

    Zhang, Jing-Jie; Yang, Juan; Li, Ying-Chao; Liu, Ning; Zhang, Run-Zhi

    2013-10-01

    The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is an infamous invasive species worldwide that aggressively attacks potato and other Solanaceae crops. CPB was first found in China in 1993 and has since spread across 2.77 × 10(5) km(2) in Xinjiang Uygur Autonomous Region. To better understand genetic variation and migration patterns, we used seven polymorphic microsatellite loci to elucidate the genetic relationships and gene flow among 10 CPB populations across Xinjiang. (i) Overall low levels of genetic diversity were detected on the entire population in Xinjiang but most of the diversity was retained among populations during invasion. (ii) The mean pairwise FST was low (0.071 ± 0.043) among populations. The genetic differentiation was little (pairwise FST 0.038 ± 0.016) between the five interior populations (Wusu, Urumqi, Jimsar, Qitai and Mulei) and Tacheng population. The six populations might come from the same genetic group via Bayesian clustering and were closely related on a neighbor-joining tree. Combining the history data, the five interior populations may have originated from Tacheng. (iii) Gene flow was frequent, especially among the five interior populations. Individuals from the interior populations could be assigned to Tacheng at higher probabilities (means 0.518 ± 0.127) than vice versa (means 0.328 ± 0.074), suggesting that the beetle population has spread from the border to the interior in Xinjiang.

  13. Characterizing Molecular Mechanisms of Imidacloprid Resistance in Select Populations of Leptinotarsa decemlineata in the Central Sands Region of Wisconsin.

    PubMed

    Clements, Justin; Schoville, Sean; Peterson, Nathan; Lan, Que; Groves, Russell L

    2016-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata (Say), is a major agricultural pest in the Central Sands region of Wisconsin. Imidacloprid, a neonicotinoid insecticide, has commonly been used for control of L. decemlineata since its registration in 1995. In the last 10 years, many field populations of L. decemlineata have begun to show increasing imidacloprid resistance. We studied resistance phenotype as a phenomenon that reduces neonicotinoid efficacy and has practical consequences for potato pest management. Although we have not observed complete field failure following the use of these products, multiple studies have demonstrated that the lethal concentration to kill 50% of the test organisms (LC50) in different field populations of L. decemlineata varies greatly which may suggest that resistance of L. decemlineata is heritable and involves genetic changes. An important challenge in understanding resistance is assessing the genetic mechanisms associated with resistance and classifying up-regulated genes that may be involved in combating an insecticide insult. In this study we uncovered trends in imidacloprid phenotypic response that have developed in the region by estimating the LC50 values among different field populations against a range of imidacloprid doses. The LC50 values collected in 2008-2011, and more recently in 2013 and 2014, show that some field locations remain susceptible to imidacloprid, while nearby fields (<100km) have developed high levels of resistance. We also sought to uncover potential mechanisms of resistance at each field location. We compiled a transcriptome for populations, characterized as phenotypically 'susceptible' and 'resistant', by isolating mRNA from adult beetles and analyzing gene expression level differences. Strong differences were observed in constituently up and down-regulated genes among different field populations. Most significantly, the up-regulation of 3 cytochrome p450s and a glutathione synthetase related

  14. Characterizing Molecular Mechanisms of Imidacloprid Resistance in Select Populations of Leptinotarsa decemlineata in the Central Sands Region of Wisconsin.

    PubMed

    Clements, Justin; Schoville, Sean; Peterson, Nathan; Lan, Que; Groves, Russell L

    2016-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata (Say), is a major agricultural pest in the Central Sands region of Wisconsin. Imidacloprid, a neonicotinoid insecticide, has commonly been used for control of L. decemlineata since its registration in 1995. In the last 10 years, many field populations of L. decemlineata have begun to show increasing imidacloprid resistance. We studied resistance phenotype as a phenomenon that reduces neonicotinoid efficacy and has practical consequences for potato pest management. Although we have not observed complete field failure following the use of these products, multiple studies have demonstrated that the lethal concentration to kill 50% of the test organisms (LC50) in different field populations of L. decemlineata varies greatly which may suggest that resistance of L. decemlineata is heritable and involves genetic changes. An important challenge in understanding resistance is assessing the genetic mechanisms associated with resistance and classifying up-regulated genes that may be involved in combating an insecticide insult. In this study we uncovered trends in imidacloprid phenotypic response that have developed in the region by estimating the LC50 values among different field populations against a range of imidacloprid doses. The LC50 values collected in 2008-2011, and more recently in 2013 and 2014, show that some field locations remain susceptible to imidacloprid, while nearby fields (<100km) have developed high levels of resistance. We also sought to uncover potential mechanisms of resistance at each field location. We compiled a transcriptome for populations, characterized as phenotypically 'susceptible' and 'resistant', by isolating mRNA from adult beetles and analyzing gene expression level differences. Strong differences were observed in constituently up and down-regulated genes among different field populations. Most significantly, the up-regulation of 3 cytochrome p450s and a glutathione synthetase related

  15. Interactions between Population Density of the Colorado Potato Beetle, Leptinotarsa decemlineata, and Herbicide Rate for Suppression of Solanaceous Weeds

    PubMed Central

    Metzger, Chase; Boydston, Rick; Ferguson, Holly; Williams, Martin M.; Zack, Richard; Walsh, Doug

    2008-01-01

    The presence of volunteer potato Solanum tuberosum L., cutleaf nightshade, S. triflorum N., and hairy nightshade, S. physalifolium Rusby (Solanales: Solanaceae), throughout potato crop rotations can diminish the effectiveness of crop rotations designed to control disease and pest problems associated with growing potatoes. In greenhouse bioassays, larvae of the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) were placed in population densities of 0, 5, 10, and 40 per potato (cv. Russet Burbank) plant and 0, 5, 10, and 15 per cutleaf nightshade and hairy nightshade plant. Plants were treated with different rates of herbicides including fluroxypyr, prometryn, and mesotrione rates, and the physiological response on the potato plants was assessed by weighing shoot biomass 14 days after treatment. Consistently, across all bioassays, rate response functions were shifted as L. decemlineata density increased, such that less herbicide was required to achieve control. For instance, the herbicide rate needed to achieve 90% reduction in potato biomass was reduced from 62 to 0 g fluroxypyr per hectare and 711 to 0 g prometryn per hectare as L. decemlineata density was increased to 40 larvae per plant. Herbivory at higher L. decemlineata population densities and herbicides above certain rates resulted in large reductions in cutleaf and hairy nightshade biomass. Differences in rate response functions among L. decemlineata population densities indicated that L. decemlineata contributed to weed suppression in combination with herbicides. These data suggest that integrated weed management systems targeting volunteer potato, cutleaf nightshade, and hairy nightshade can be more effective when herbicide applications are combined with herbivory by naturally occurring Colorado potato beetles. PMID:20298117

  16. Characterizing Molecular Mechanisms of Imidacloprid Resistance in Select Populations of Leptinotarsa decemlineata in the Central Sands Region of Wisconsin

    PubMed Central

    Clements, Justin; Schoville, Sean; Peterson, Nathan; Lan, Que; Groves, Russell L.

    2016-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata (Say), is a major agricultural pest in the Central Sands region of Wisconsin. Imidacloprid, a neonicotinoid insecticide, has commonly been used for control of L. decemlineata since its registration in 1995. In the last 10 years, many field populations of L. decemlineata have begun to show increasing imidacloprid resistance. We studied resistance phenotype as a phenomenon that reduces neonicotinoid efficacy and has practical consequences for potato pest management. Although we have not observed complete field failure following the use of these products, multiple studies have demonstrated that the lethal concentration to kill 50% of the test organisms (LC50) in different field populations of L. decemlineata varies greatly which may suggest that resistance of L. decemlineata is heritable and involves genetic changes. An important challenge in understanding resistance is assessing the genetic mechanisms associated with resistance and classifying up-regulated genes that may be involved in combating an insecticide insult. In this study we uncovered trends in imidacloprid phenotypic response that have developed in the region by estimating the LC50 values among different field populations against a range of imidacloprid doses. The LC50 values collected in 2008–2011, and more recently in 2013 and 2014, show that some field locations remain susceptible to imidacloprid, while nearby fields (<100km) have developed high levels of resistance. We also sought to uncover potential mechanisms of resistance at each field location. We compiled a transcriptome for populations, characterized as phenotypically ‘susceptible’ and ‘resistant’, by isolating mRNA from adult beetles and analyzing gene expression level differences. Strong differences were observed in constituently up and down-regulated genes among different field populations. Most significantly, the up-regulation of 3 cytochrome p450s and a glutathione synthetase

  17. [Insecticidal and immunosuppressive effect of ascomycete Cordyceps militaris on the larvae of the Colorado potato beetle Leptinotarsa decemlineata].

    PubMed

    Kriukov, V Iu; Iaroslavtseva, O N; Dubovskiĭ, I M; Tiurin, M V; Kriukova, N A; Glupov, V V

    2014-01-01

    The immunosuppressive and insecticidal activity of cultures of the entomopathogenic fungus Cordyceps militaris on the larvae of the Colorado potato beetle Leptinotarsa decemlineata has been established for the first time. It was found that the peroral effect of the fungal culture resulted in dose-dependent decrease in survival, delayed in development time and molting, decreases in the total hemocyt counts, increased activity of phenoloxidases in the hemolymph, and reduced activity of the enzyme in the cuticle, as well as increased sensitivity of larvae to the fungus Beauveria bassiana at the level of the synergistic effect. PMID:25731041

  18. [Insecticidal and immunosuppressive effect of ascomycete Cordyceps militaris on the larvae of the Colorado potato beetle Leptinotarsa decemlineata].

    PubMed

    Kriukov, V Iu; Iaroslavtseva, O N; Dubovskiĭ, I M; Tiurin, M V; Kriukova, N A; Glupov, V V

    2014-01-01

    The immunosuppressive and insecticidal activity of cultures of the entomopathogenic fungus Cordyceps militaris on the larvae of the Colorado potato beetle Leptinotarsa decemlineata has been established for the first time. It was found that the peroral effect of the fungal culture resulted in dose-dependent decrease in survival, delayed in development time and molting, decreases in the total hemocyt counts, increased activity of phenoloxidases in the hemolymph, and reduced activity of the enzyme in the cuticle, as well as increased sensitivity of larvae to the fungus Beauveria bassiana at the level of the synergistic effect.

  19. Leaf surface sesquiterpene alcohols of the potato (Solanum tuberosum) and their influence on colorado beetle (Leptinotarsa decemlineata Say) feeding.

    PubMed

    Szafranek, Beata; Chrapkowska, Karolina; Waligóra, Danuta; Palavinskas, Richard; Banach, Arkadiusz; Szafranek, Janusz

    2006-10-01

    The structures of two previously unknown sesquiterpene alcohols of the potato (Solanum tuberosum) were assigned. The potato alcohols were obtained by steam-distillation, preparative column chromatography, and separation into fractions by HPLC on a silica gel column. The fractions were studied by GC-FID, GC-MS, and NMR spectroscopy. The potato sesquiterpene alcohols were identified as kunzeaol (6-alpha-hydroxygermacra-1(10),4-diene) and ledol. These two compounds were used in feeding tests with larvae and beetles of the Colorado potato beetle (Leptinotarsa decemlineata Say). In a bioassay, kunzeaol was found to act as a feeding attractant for the beetles.

  20. Suppression of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera:Chrysomelidae), on solanaceous crops with a copper-based fungicide

    SciTech Connect

    Hare, J.D.

    1984-08-01

    Field experiments were carried out to determine if a copper-based fungicide known to deter feeding by the Colorado potato beetle, Leptinotarsa decemlineata (Say), in the laboratory, could suppress the growth of L. decemlineata populations in the field when used regularly for plant disease protection on tomatoes, potatoes, and eggplants. Larval densities on plants treated with a fungicide formulated with copper hydroxide (Cu(OH)/sub 2/) were between 44 and 100% lower than on untreated control plants or plants treated with a more commonly used fungicide, mancozeb. The greatest reductions occurred on tomatoes, the least suitable host of the three for L. decemlineata growth and survival.

  1. Physicochemical comparison of chitin and chitosan obtained from larvae and adult Colorado potato beetle (Leptinotarsa decemlineata).

    PubMed

    Kaya, Murat; Baran, Talat; Erdoğan, Sevil; Menteş, Ayfer; Özüsağlam, Meltem Aşan; Çakmak, Yavuz Selim

    2014-12-01

    Chitins and chitosans obtained from larva and adult Colorado potato beetles (Leptinotarsa decemlineata) were physico-chemically characterized and differences between adults and larvae were identified. The dry weight chitin contents of the adult Colorado potato beetles and larvae were determined as 20% and 7%, respectively. The chitin produced chitosan yields of 72% from the adult Colorado potato beetles and 67% from the larvae. FTIR analysis showed that the isolated chitins were in the alpha form. Crystalline index values, determined by XRD, were 72% for larvae and 76% for adults. The degradation temperatures of the isolated chitin structures were measured by TGA, and this showed that the chitin from adult Colorado potato beetles had a more stable structure than that from the larvae. The surface morphologies of the isolated chitin and chitosan structures were analysed with SEM and it was revealed that these structures consisted of nanofibres. According to elemental analysis, the purity of chitin and chitosan from adults was greater than that from the larvae. The results of molecular analysis showed that the chitosans from adults (2.722 kDa) and larvae (2.676 kDa) of the Colorado potato beetle have low molecular weights. Antimicrobial and antioxidant activities of both adult and larval chitosans were determined. The adult potato beetle is more appropriate than the larvae as an alternative chitin source because of the fact that its dry weight chitin content, chitosan yield and purity of chitin are higher than those from the larvae, and its antimicrobial and antioxidant activities are also higher than those from the larvae. PMID:25491803

  2. Effects of landscape composition and rotation distance on Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) abundance in cultivated potato.

    PubMed

    Huseth, A S; Frost, K E; Knuteson, D L; Wyman, J A; Groves, R L

    2012-12-01

    Knowledge of the Colorado potato beetle's, Leptinotarsa decemlineata (Say), relationship to previous potato crops has contributed to the development of a pest management strategy focused upon crop rotation. Previous investigations revealed that potato rotations exceeding 0.4 km were effective in reducing colonization in current season potato. The current study examines the relationship between beetle abundance in potato (Solanum tuberosum L.) and distance from multiple, previous year potato fields in Wisconsin, and integrates information about the influence of natural habitats adjacent to previous season potato. Colorado potato beetle count data were collected in 1998 and 2008 and distance to previous potato, field areas, and landscape classes were estimated using maps from 1997 and 2007. Poisson regression was used to relate counts to combinations of distance and local landscape characteristics calculated for all fields within 1,500 m of sampled potato. In 1998, beetle counts measured in current season potato declined significantly with increasing distance from previous potato fields and field size did not influence these counts. However, there was no relationship between beetle abundance and distance to prior year potatoes in 2008. In both years, increased proportions of surrounding habitats, previously described as preferred for diapause sites (e.g., wooded field boundaries), did not relate significantly to counts. However, grassland habitat was negatively correlated with counts. Results indicate that distance from previous potato remains an important factor to reduce the magnitude of colonization. This analysis further suggests that certain landscape components (e.g., grassland) may influence infestation, which may be useful for refining future integrated pest management programs. PMID:23321104

  3. Physicochemical comparison of chitin and chitosan obtained from larvae and adult Colorado potato beetle (Leptinotarsa decemlineata).

    PubMed

    Kaya, Murat; Baran, Talat; Erdoğan, Sevil; Menteş, Ayfer; Özüsağlam, Meltem Aşan; Çakmak, Yavuz Selim

    2014-12-01

    Chitins and chitosans obtained from larva and adult Colorado potato beetles (Leptinotarsa decemlineata) were physico-chemically characterized and differences between adults and larvae were identified. The dry weight chitin contents of the adult Colorado potato beetles and larvae were determined as 20% and 7%, respectively. The chitin produced chitosan yields of 72% from the adult Colorado potato beetles and 67% from the larvae. FTIR analysis showed that the isolated chitins were in the alpha form. Crystalline index values, determined by XRD, were 72% for larvae and 76% for adults. The degradation temperatures of the isolated chitin structures were measured by TGA, and this showed that the chitin from adult Colorado potato beetles had a more stable structure than that from the larvae. The surface morphologies of the isolated chitin and chitosan structures were analysed with SEM and it was revealed that these structures consisted of nanofibres. According to elemental analysis, the purity of chitin and chitosan from adults was greater than that from the larvae. The results of molecular analysis showed that the chitosans from adults (2.722 kDa) and larvae (2.676 kDa) of the Colorado potato beetle have low molecular weights. Antimicrobial and antioxidant activities of both adult and larval chitosans were determined. The adult potato beetle is more appropriate than the larvae as an alternative chitin source because of the fact that its dry weight chitin content, chitosan yield and purity of chitin are higher than those from the larvae, and its antimicrobial and antioxidant activities are also higher than those from the larvae.

  4. Effects of landscape composition and rotation distance on Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) abundance in cultivated potato.

    PubMed

    Huseth, A S; Frost, K E; Knuteson, D L; Wyman, J A; Groves, R L

    2012-12-01

    Knowledge of the Colorado potato beetle's, Leptinotarsa decemlineata (Say), relationship to previous potato crops has contributed to the development of a pest management strategy focused upon crop rotation. Previous investigations revealed that potato rotations exceeding 0.4 km were effective in reducing colonization in current season potato. The current study examines the relationship between beetle abundance in potato (Solanum tuberosum L.) and distance from multiple, previous year potato fields in Wisconsin, and integrates information about the influence of natural habitats adjacent to previous season potato. Colorado potato beetle count data were collected in 1998 and 2008 and distance to previous potato, field areas, and landscape classes were estimated using maps from 1997 and 2007. Poisson regression was used to relate counts to combinations of distance and local landscape characteristics calculated for all fields within 1,500 m of sampled potato. In 1998, beetle counts measured in current season potato declined significantly with increasing distance from previous potato fields and field size did not influence these counts. However, there was no relationship between beetle abundance and distance to prior year potatoes in 2008. In both years, increased proportions of surrounding habitats, previously described as preferred for diapause sites (e.g., wooded field boundaries), did not relate significantly to counts. However, grassland habitat was negatively correlated with counts. Results indicate that distance from previous potato remains an important factor to reduce the magnitude of colonization. This analysis further suggests that certain landscape components (e.g., grassland) may influence infestation, which may be useful for refining future integrated pest management programs.

  5. Knockdown of a putative alanine aminotransferase gene affects amino acid content and flight capacity in the Colorado potato beetle Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Fu, Kai-Yun; Lü, Feng-Gong; Guo, Wen-Chao; Li, Guo-Qing

    2015-07-01

    Alanine aminotransferase (ALT) plays important physiological and biochemical roles in insect. In this study, a full-length Ldalt cDNA was cloned from Leptinotarsa decemlineata. It was ubiquitously expressed in the eggs, larvae, pupae and adults. In the adults, Ldalt mRNA was widely distributed in thorax muscles, fat body, midgut, foregut, hindgut, Malpighian tubules, ventral ganglion and epidermis, with the expression levels from the highest to the lowest. Two double-stranded RNAs (dsRNAs) (dsLdalt1 and dsLdalt2) targeting Ldalt were constructed and bacterially expressed. After adults fed on dsLdalt1- and dsLdalt2-immersed foliage for 3 day, Ldalt mRNA abundance was significantly decreased by 79.5 and 71.1 %, and ALT activities were significantly reduced by 64.5 and 67.6 %, respectively. Moreover, silencing Ldalt affected free amino acid contents. Lysine was decreased by 100.0 and 100.0 %, and arginine was reduced by 87.5 and 89.4 %, respectively, in the hemolymph from dsLdalt1- and dsLdalt2-ingested beetles, compared with control ones. In contrast, proline was increased by 88.7 and 96.4 %. Furthermore, ingestion of dsLdalt1 and dsLdalt2 significantly decreased flight speed, shortened flight duration time and flight distance. In addition, knocking down Ldalt significantly increased adult mortality. These data imply that LdALT plays important roles in amino acid metabolism and in flight in L. decemlineata.

  6. Northward range expansion requires synchronization of both overwintering behaviour and physiology with photoperiod in the invasive Colorado potato beetle (Leptinotarsa decemlineata).

    PubMed

    Lehmann, Philipp; Lyytinen, Anne; Piiroinen, Saija; Lindström, Leena

    2014-09-01

    Photoperiodic phenological adaptations are prevalent in many organisms living in seasonal environments. As both photoperiod and growth season length change with latitude, species undergoing latitudinal range expansion often need to synchronize their life cycle with a changing photoperiod and growth season length. Since adaptive synchronization often involves a large number of time-consuming genetic changes, behavioural plasticity might be a faster way to adjust to novel conditions. We compared behavioural and physiological traits in overwintering (diapause) preparation in three latitudinally different European Colorado potato beetle (Leptinotarsa decemlineata) populations reared under two photoperiods. Our aim was to study whether behavioural plasticity could play a role in rapid range expansion into seasonal environments. Our results show that while burrowing into the soil occurred in the southernmost studied population also under a non-diapause-inducing long photoperiod, the storage lipid content of these beetles was very low compared to the northern populations. However, similar behavioural plasticity was not found in the northern populations. Furthermore, the strongest suppression of energy metabolism was seen in pre-diapause beetles from the northernmost population. These results could indicate accelerated diapause preparation and possibly energetic adjustments due to temporal constraints imposed by a shorter, northern, growth season. Our results indicate that behavioural plasticity in burrowing may have facilitated initial range expansion of L. decemlineata in Europe. However, long-term persistence at high latitudes has required synchronization of burrowing behaviour with physiological traits. The results underline that eco-physiological life-history traits of insects, such as diapause, should be included in studies on range expansion. PMID:25012598

  7. Nuclear receptor ecdysone-induced protein 75 is required for larval-pupal metamorphosis in the Colorado potato beetle Leptinotarsa decemlineata (Say).

    PubMed

    Guo, W-C; Liu, X-P; Fu, K-Y; Shi, J-F; Lü, F-G; Li, G-Q

    2016-02-01

    20-hydroxyecdysone (20E) and juvenile hormone (JH) are key regulators of insect development. In this study, three Leptinotarsa decemlineata Ecdysone-induced protein 75 (LdE75) cDNAs (LdE75A, B and C) were cloned from L. decemlineata. The three LdE75 isoforms were highly expressed just before or right after each moult. Within the fourth larval instar, they showed a small rise and a big peak 40 and 80 h after ecdysis. The expression peaks of the three LdE75s coincided with the peaks of circulating 20E levels. In vitro midgut culture and in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide (Hal) enhanced LdE75 expression in the day 1 final larval instars. Conversely, a decrease in 20E by feeding a double-stranded RNA (dsRNA) against an ecdysteroidogenesis gene, Shade (LdSHD), repressed the expression of LdE75. Moreover, Hal upregulated the expression of the three LdE75s in LdSHD-silenced larvae. Thus, 20E pulses activate the transcription of LdE75s. Furthermore, ingesting dsE75-1 and dsE75-2 from a common fragment of the three isoforms successfully knocked down these LdE75s, and caused developmental arrest. Finally, knocking down LdE75s significantly repressed the transcription of three ecdysteroidogenesis genes, lowered the 20E titre and affected the expression of two 20E-response genes. Silencing LdE75s also induced the expression of a JH biosynthesis gene, increased JH titre and activated the transcription of a JH early-inducible gene. Thus, Ld E75s are required for larval-pupal metamorphosis and act mainly by modulating 20E and JH titres and mediating their signalling pathways. PMID:26542892

  8. Knockdown of a putative alanine aminotransferase gene affects amino acid content and flight capacity in the Colorado potato beetle Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Fu, Kai-Yun; Lü, Feng-Gong; Guo, Wen-Chao; Li, Guo-Qing

    2015-07-01

    Alanine aminotransferase (ALT) plays important physiological and biochemical roles in insect. In this study, a full-length Ldalt cDNA was cloned from Leptinotarsa decemlineata. It was ubiquitously expressed in the eggs, larvae, pupae and adults. In the adults, Ldalt mRNA was widely distributed in thorax muscles, fat body, midgut, foregut, hindgut, Malpighian tubules, ventral ganglion and epidermis, with the expression levels from the highest to the lowest. Two double-stranded RNAs (dsRNAs) (dsLdalt1 and dsLdalt2) targeting Ldalt were constructed and bacterially expressed. After adults fed on dsLdalt1- and dsLdalt2-immersed foliage for 3 day, Ldalt mRNA abundance was significantly decreased by 79.5 and 71.1 %, and ALT activities were significantly reduced by 64.5 and 67.6 %, respectively. Moreover, silencing Ldalt affected free amino acid contents. Lysine was decreased by 100.0 and 100.0 %, and arginine was reduced by 87.5 and 89.4 %, respectively, in the hemolymph from dsLdalt1- and dsLdalt2-ingested beetles, compared with control ones. In contrast, proline was increased by 88.7 and 96.4 %. Furthermore, ingestion of dsLdalt1 and dsLdalt2 significantly decreased flight speed, shortened flight duration time and flight distance. In addition, knocking down Ldalt significantly increased adult mortality. These data imply that LdALT plays important roles in amino acid metabolism and in flight in L. decemlineata. PMID:25868655

  9. Identification of ten mevalonate enzyme-encoding genes and their expression in response to juvenile hormone levels in Leptinotarsa decemlineata (Say).

    PubMed

    Li, Qian; Meng, Qing-Wei; Lü, Feng-Gong; Guo, Wen-Chao; Li, Guo-Qing

    2016-06-15

    The mevalonate pathway is responsible for the biosynthesis of many essential molecules important in insect development, reproduction, chemical communication and defense. Based on Leptinotarsa decemlineata transcriptome and genome data, we identified ten genes that encoded acetoacetyl-CoA thiolase (LdAACT1 and LdAACT2), hydroxymethylglutaryl (HMA)-CoA synthase (LdHMGS), HMG-CoA reductase (LdHMGR1 and LdHMGR2), mevalonate kinase (LdMevK), phospho-mevalonate kinase (LdPMK), mevalonate diphosphate decarboxylase (LdMDD), isopentenyl-diphosphate isomerase (LdIDI) and farnesyl pyrophosphate synthetase (LdFPPS). Nine of these genes (except for LdAACT1) were mainly expressed in the larval brain-corpora cardiaca-corpora allata complex, and adult ovary and testis. The 9 genes were transcribed at high levels right after each ecdysis, and at low levels in the mid instar. Therefore, the 9 genes were indicated to be involved in JH biosynthesis. Moreover, knockdown of a JH biosynthesis gene LdJHAMT to lower JH titer significantly downregulated the transcription of the 9 genes. Ingestion of JH to activate JH signaling also significantly suppressed the expression of the 9 genes. It appears that the accumulation of JH precursors in LdJHAMT RNAi larvae and a high JH titer in JH-fed specimens may cause negative feedbacks to repress the expression of the 9 mevalonate enzyme-encoding genes (excluding LdAACT1) to balance the enzyme quantity in L. decemlineata. PMID:26899871

  10. Northward range expansion requires synchronization of both overwintering behaviour and physiology with photoperiod in the invasive Colorado potato beetle (Leptinotarsa decemlineata).

    PubMed

    Lehmann, Philipp; Lyytinen, Anne; Piiroinen, Saija; Lindström, Leena

    2014-09-01

    Photoperiodic phenological adaptations are prevalent in many organisms living in seasonal environments. As both photoperiod and growth season length change with latitude, species undergoing latitudinal range expansion often need to synchronize their life cycle with a changing photoperiod and growth season length. Since adaptive synchronization often involves a large number of time-consuming genetic changes, behavioural plasticity might be a faster way to adjust to novel conditions. We compared behavioural and physiological traits in overwintering (diapause) preparation in three latitudinally different European Colorado potato beetle (Leptinotarsa decemlineata) populations reared under two photoperiods. Our aim was to study whether behavioural plasticity could play a role in rapid range expansion into seasonal environments. Our results show that while burrowing into the soil occurred in the southernmost studied population also under a non-diapause-inducing long photoperiod, the storage lipid content of these beetles was very low compared to the northern populations. However, similar behavioural plasticity was not found in the northern populations. Furthermore, the strongest suppression of energy metabolism was seen in pre-diapause beetles from the northernmost population. These results could indicate accelerated diapause preparation and possibly energetic adjustments due to temporal constraints imposed by a shorter, northern, growth season. Our results indicate that behavioural plasticity in burrowing may have facilitated initial range expansion of L. decemlineata in Europe. However, long-term persistence at high latitudes has required synchronization of burrowing behaviour with physiological traits. The results underline that eco-physiological life-history traits of insects, such as diapause, should be included in studies on range expansion.

  11. Nuclear receptor ecdysone-induced protein 75 is required for larval-pupal metamorphosis in the Colorado potato beetle Leptinotarsa decemlineata (Say).

    PubMed

    Guo, W-C; Liu, X-P; Fu, K-Y; Shi, J-F; Lü, F-G; Li, G-Q

    2016-02-01

    20-hydroxyecdysone (20E) and juvenile hormone (JH) are key regulators of insect development. In this study, three Leptinotarsa decemlineata Ecdysone-induced protein 75 (LdE75) cDNAs (LdE75A, B and C) were cloned from L. decemlineata. The three LdE75 isoforms were highly expressed just before or right after each moult. Within the fourth larval instar, they showed a small rise and a big peak 40 and 80 h after ecdysis. The expression peaks of the three LdE75s coincided with the peaks of circulating 20E levels. In vitro midgut culture and in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide (Hal) enhanced LdE75 expression in the day 1 final larval instars. Conversely, a decrease in 20E by feeding a double-stranded RNA (dsRNA) against an ecdysteroidogenesis gene, Shade (LdSHD), repressed the expression of LdE75. Moreover, Hal upregulated the expression of the three LdE75s in LdSHD-silenced larvae. Thus, 20E pulses activate the transcription of LdE75s. Furthermore, ingesting dsE75-1 and dsE75-2 from a common fragment of the three isoforms successfully knocked down these LdE75s, and caused developmental arrest. Finally, knocking down LdE75s significantly repressed the transcription of three ecdysteroidogenesis genes, lowered the 20E titre and affected the expression of two 20E-response genes. Silencing LdE75s also induced the expression of a JH biosynthesis gene, increased JH titre and activated the transcription of a JH early-inducible gene. Thus, Ld E75s are required for larval-pupal metamorphosis and act mainly by modulating 20E and JH titres and mediating their signalling pathways.

  12. Variation in Hsp70 levels after cold shock: signs of evolutionary responses to thermal selection among Leptinotarsa decemlineata populations.

    PubMed

    Lyytinen, Anne; Mappes, Johanna; Lindström, Leena

    2012-01-01

    Individuals of widely spread species are expected to show local adaption in temperature tolerance as they encounter a range of thermal conditions. We tracked thermal adaptations of the Colorado potato beetle (Leptinotarsa decemlineata) that invaded Europe within the last 100 years. It has occupied various conditions although, like the majority of invasive species, it lost a measurable amount of neutral genetic variation due to bottleneck effect when it invaded Europe. We exposed diapausing beetles originated from three different latitudes (54°N, 59°N, 60°N) to cold shock (-5°C, 1.5 hrs) in order to test if beetles from the northern populations express differential levels of cold-induced and constitutive Hsp70 compared to the beetles from milder temperature regime. The level of cold-induced Hsp70 was lowest in the northernmost beetle populations while the level of constitutive Hsp70 did not differ with the population. Moreover, the southernmost beetles were more plastic in their response to cold shock than the northernmost beetles. These results suggest that physiological adaptation, like the synthesis of Hsp70, can evolve very quickly.

  13. A comparison of internal and external lipids of nondiapausing and diapause initiation phase adult Colorado potato beetles, Leptinotarsa decemlineata.

    PubMed

    Yocum, George D; Buckner, James S; Fatland, Charlotte L

    2011-07-01

    The Colorado potato beetle, Leptinotarsa decemlineata, reared under diapause-inducing conditions will emerge from the soil as an adult and enter the diapause initiation phase, a period where metabolic reserves are stockpiled before the beetles enter the nonfeeding diapause maintenance phase. Internal and external lipids were characterized during the diapause initiation phase (IP) and compared to the lipid profiles of nondiapausing adults. The primary internal lipids of both diapause IP and nondiapausing adults are triacylglycerols. Only trace amounts of internal lipids were detected in day 1 diapause IP adults. A dramatic increase in internal lipids was observed between day 7 and day 15 post-emergence in the diapause IP adults. The majority of the triacylglycerol isomers were identified as C50, C52 and C54 chain lengths by GC-MS. There were no observed differences in the isomeric distribution of the major internal lipids between diapause IP and nondiapausing adults. External lipids were mainly methyl-branched alkanes containing a 25 to 53 carbon backbone. The quantity of external lipids increased from day 1 to day 7 post-emergence in both the diapause IP and nondiapausing adults, with the bulk of the increase occurring in the longer chain-length methylalkanes.

  14. Responses of parasiteEdovum puttleri to kairomone from eggs of colorado potato beetle,Leptinotarsa decemlineata.

    PubMed

    Leonard, D E; Wu, Z X; Ferro, D N

    1987-02-01

    When females of the eulophid parasiteEdovum puttleri were exposed to ann-hexane wash of eggs of the Colorado potato beetle,Leptinotarsa decemlineata, their responses indicated that the eggs contained a kairomone which elicited host-finding and host-acceptance behaviors. The hostfinding responses included an increased amount of time searching glass beads treated with kairomone, and drumming on the beads with the flagellum of the antennae. Host-acceptance responses included grasping of the beads with the legs, raising of the abdomen, and probing the kairomone-treated surface with the ovipositor. None of these responses were noted in females on beads treated only with hexane, or in males exposed to kairomone-treated beads. When kairomone was applied to a flat surface, filter paper disks, few episodes of drumming and no episodes of probing with the ovipositor were noted. Responses ofE.puttleri to eggs of Colorado potato beetle were similar to those on kairomone-treated beads, but females normally drilled into eggs and fed on host fluids after retracting the ovipositor. The kairomone is volatile, and responsiveness was reduced in parasites exposed to beads treated several hours previously.

  15. RNAi suppression of the ryanodine receptor gene results in decreased susceptibility to chlorantraniliprole in Colorado potato beetle Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Guo, Wei-Yan; Yang, Yao; Lü, Feng-Gong; Lu, Wei-Ping; Li, Guo-Qing

    2014-04-01

    Leptinotarsadecemlineata is the most important pest in potato and causes serious yield loss each year. Chlorantraniliprole acts on insect ryanodine receptors (RyRs) and is among the most active compounds against L. decemlineata. Here we cloned and characterized a 15,792-bp full-length LdRyR cDNA that encoded a 5128-amino acid protein. LdRyR shares 85-92% amino acid similarities with other insect RyR homologues, and 59-61% similarities with those from Caenorhabditis elegans and Homo sapiens. All hallmarks of the RyR proteins are conserved in LdRyR. LdRyR has a MIR domain, two RIH domains, three SPRY domains, four copies of RyR domain and a RIH-associated domain in the N-terminus, and it possesses two consensus calcium ion-binding EF-hand motifs and six predicted transmembrane helices in the C-terminus. Temporal, spatial and tissue-specific expression patterns of LdRyR were evaluated. LdRyR expression level was increased constantly from egg to wandering stages, dropped in pupal stage and was increased again in the adult stage. It was widely expressed in the head, thorax and abdomen of day 3 fourth-instar larvae. Moreover, it was ubiquitously expressed in all inspected tissues including epidermis, foregut, midgut, ileum, rectum, fat body, ventral ganglia and Malpighian tubules in day 3 fourth-instar larvae. Dietary introduction of double-stranded RNA of LdRyR significantly reduced the mRNA levels of the target gene in the larvae and adults, respectively, and significantly decreased chlorantraniliprole-induced mortalities. Thus, our results suggested that LdRyR encoded a functional ryanodine receptor in L. decemlineata. PMID:24607641

  16. RNAi suppression of the ryanodine receptor gene results in decreased susceptibility to chlorantraniliprole in Colorado potato beetle Leptinotarsa decemlineata.

    PubMed

    Wan, Pin-Jun; Guo, Wei-Yan; Yang, Yao; Lü, Feng-Gong; Lu, Wei-Ping; Li, Guo-Qing

    2014-04-01

    Leptinotarsadecemlineata is the most important pest in potato and causes serious yield loss each year. Chlorantraniliprole acts on insect ryanodine receptors (RyRs) and is among the most active compounds against L. decemlineata. Here we cloned and characterized a 15,792-bp full-length LdRyR cDNA that encoded a 5128-amino acid protein. LdRyR shares 85-92% amino acid similarities with other insect RyR homologues, and 59-61% similarities with those from Caenorhabditis elegans and Homo sapiens. All hallmarks of the RyR proteins are conserved in LdRyR. LdRyR has a MIR domain, two RIH domains, three SPRY domains, four copies of RyR domain and a RIH-associated domain in the N-terminus, and it possesses two consensus calcium ion-binding EF-hand motifs and six predicted transmembrane helices in the C-terminus. Temporal, spatial and tissue-specific expression patterns of LdRyR were evaluated. LdRyR expression level was increased constantly from egg to wandering stages, dropped in pupal stage and was increased again in the adult stage. It was widely expressed in the head, thorax and abdomen of day 3 fourth-instar larvae. Moreover, it was ubiquitously expressed in all inspected tissues including epidermis, foregut, midgut, ileum, rectum, fat body, ventral ganglia and Malpighian tubules in day 3 fourth-instar larvae. Dietary introduction of double-stranded RNA of LdRyR significantly reduced the mRNA levels of the target gene in the larvae and adults, respectively, and significantly decreased chlorantraniliprole-induced mortalities. Thus, our results suggested that LdRyR encoded a functional ryanodine receptor in L. decemlineata.

  17. The influence of potato endophytes on Leptinotarsa decemlineata endosymbionts promotes mortality of the pest.

    PubMed

    Sorokan, Antonina V; Ben'kovskaya, Galina V; Maksimov, Igor' V

    2016-05-01

    Plants are exposed to pervasive attack by diverse attackers, such as pathogens and pests. But plants have their own endophytic microflora as well as the attacking insects. These microbiomes contact face to face in the nature. It has been found that the endophytic strain Bacillus subtilis 26D increases mortality of Colorado potato beetles, disturbing the development of insect microsymbionts Enterobacter ssp. and Acinetobacter ssp. PMID:26968115

  18. The influence of potato endophytes on Leptinotarsa decemlineata endosymbionts promotes mortality of the pest.

    PubMed

    Sorokan, Antonina V; Ben'kovskaya, Galina V; Maksimov, Igor' V

    2016-05-01

    Plants are exposed to pervasive attack by diverse attackers, such as pathogens and pests. But plants have their own endophytic microflora as well as the attacking insects. These microbiomes contact face to face in the nature. It has been found that the endophytic strain Bacillus subtilis 26D increases mortality of Colorado potato beetles, disturbing the development of insect microsymbionts Enterobacter ssp. and Acinetobacter ssp.

  19. Knockdown of a nutrient amino acid transporter gene LdNAT1 reduces free neutral amino acid contents and impairs Leptinotarsa decemlineata pupation

    PubMed Central

    Fu, Kai-Yun; Guo, Wen-Chao; Ahmat, Tursun; Li, Guo-Qing

    2015-01-01

    A Leptinotarsa decemlineata SLC6 NAT gene (LdNAT1) was cloned. LdNAT1 was highly expressed in the larval alimentary canal especially midgut. LdNAT1 mRNA levels were high right after the molt and low just before the molt. JH and a JH analog pyriproxyfen activated LdNAT1 expression. RNAi of an allatostatin gene LdAS-C increased JH and upregulated LdNAT1 transcription. Conversely, silencing of a JH biosynthesis gene LdJHAMT decreased JH and reduced LdNAT1 expression. Moreover, 20E and an ecdysteroid agonist halofenozide repressed LdNAT1 expression, whereas a decrease in 20E by RNAi of an ecdysteroidogenesis gene LdSHD and disruption of 20E signaling by knockdown of LdE75 and LdFTZ-F1 activated LdNAT1 expression. Thus, LdNAT1 responded to both 20E and JH. Moreover, knockdown of LdNAT1 reduced the contents of cysteine, histidine, isoleucine, leucine, methionine, phenylalanine and serine in the larval bodies and increased the contents of these amino acids in the larval feces. Furthermore, RNAi of LdNAT1 inhibited insulin/target of rapamycin pathway, lowered 20E and JH titers, reduced 20E and JH signaling, retarded larval growth and impaired pupation. These data showed that LdNAT1 was involved in the absorption of several neutral amino acids critical for larval growth and metamorphosis. PMID:26657797

  20. Seasonal occurrence and relative abundance of aphids on potato plants with classical and transgenic characters of resistance to Colorado potato beetle Leptinotarsa decemlineata (Say).

    PubMed

    Ashouri, A

    2004-01-01

    The seasonal abundance and dynamics of potato-infesting aphids were studied in two seasons, on potato Solanum tuberosum L. with various types of transgenic and classical resistance to primary pests, especially the Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say). The lines tested were the NewLeaf potato, a transgenic expressing the Bacillus thuringiensis CryIIIA toxin (BTT); NYL 235-4 a parental line derived from S. berthaultii (NYL) with a high density of glandular trichomes; and a transgenic line expressing oryzacystatln I (OCI), a proteinase inhibitor gene from rice; potatoes from two commercial cultivars, Superior and Kennebec, served as controls. Over the two seasons, Macrosiphum euphorbiae (Thomas) and, to a lesser extent, Myzus persicae (Sulzer) were by far the most abundant aphids observed in the experimental plots. M. persicae was observed relatively late in the season, and was most abundant on the Kennebec-OCI potato. Macrosiphum euphorbiae was more regular over seasons, and its highest densities were observed on the NYL 235-4 line. The population of M. euphorbiae showed markedly different patterns on the five lines studied, which was clearly related to potato plant phenology. Density of M. euphorbiae was observed on the NYL 235-4 line, in late July and early August.

  1. Knockdown of a putative insulin-like peptide gene LdILP2 in Leptinotarsa decemlineata by RNA interference impairs pupation and adult emergence.

    PubMed

    Fu, Kai-Yun; Zhu, Tao-Tao; Guo, Wen-Chao; Ahmat, Tursun; Li, Guo-Qing

    2016-05-01

    Five insulin-like peptide LdILP genes were identified in Leptinotarsa decemlineata. All of them contained three exons and two introns, with three genes tandemly arrayed and well separated from the other two. Phylogenetic analysis revealed that the three LdILPs from three tandemly-arrayed genes grouped with TcILP1, whereas the other two resembled with TcILP2 and TcILP4 from Tribolium castaneum. Thus, the five LdILP genes were provisionally named LdILP1a, LdILP1b, LdILP1c, LdILP2 and LdILP4. LdILP2 was widely expressed in several tissues such as the brain-corpora cardiaca-corpora allata (BR-CC-CA) complex, gut and fat body. In contrast, LdILP1a and LdILP1b were only transcribed in BR-CC-CA, LdILP4 was in ovaries, and LdILP1c was in both BR-CC-CA and ovaries. Ingestion of double-stranded RNAs (dsRNAs) targeting LdILP2 (dsLdILP2-1 and dsLdILP2-2) specifically knocked down LdILP2 and upregulated the transcription of both LdInR and Ld4EBP, indicating insulin/insulin-like growth factor signaling pathway (IIS) was inhibited. Approximately 50% of the LdILP2 RNAi larvae did not normally pupate and about 50% of the LdILP2 RNAi pupae did not emerge. Moreover, silencing LdILP2 reduced the expression of a juvenile hormone (JH) biosynthesis gene, lowered JH titer and disturbed JH signaling. Finally, knocking down LdILP2 inhibited an ecdysteroidogenesis gene, decreased 20-hydroxyecdysone (20E) titer, and repressed the expression of two 20E-response genes LdHR3 and LdFTZ-F1. Thus, the IIS pathway is involved in larval-pupal metamorphosis by modification of both JH and 20E signaling in L. decemlineata. PMID:26812356

  2. Functions of nuclear receptor HR3 during larval-pupal molting in Leptinotarsa decemlineata (Say) revealed by in vivo RNA interference.

    PubMed

    Guo, Wen-Chao; Liu, Xin-Ping; Fu, Kai-Yun; Shi, Ji-Feng; Lü, Feng-Gong; Li, Guo-Qing

    2015-08-01

    Our previous results revealed that RNA interference-aided knockdown of Leptinotarsa decemlineata FTZ-F1 (LdFTZ-F1) reduced 20E titer, and impaired pupation. In this study, we characterized a putative LdHR3 gene, an early-late 20E-response gene upstream of LdFTZ-F1. Within the first, second and third larval instars, three expression peaks of LdHR3 occurred just before the molt. In the fourth (final) larval instar 80 h after ecdysis and prepupal stage 3 days after burying into soil, two LdHR3 peaks occurred. The LdHR3 expression peaks coincide with the peaks of circulating 20E level. In vitro midgut culture and in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide (Hal) enhanced LdHR3 expression in the final larval instars. Conversely, a decrease in 20E by feeding a double-stranded RNA (dsRNA) against an ecdysteroidogenesis gene Ldshd repressed the expression. Moreover, Hal rescued the transcript levels in the Ldshd-silenced larvae. Thus, 20E peaks activate the expression of LdHR3. Furthermore, ingesting dsRNA against LdHR3 successfully knocked down the target gene, and impaired pupation. Finally, knockdown of LdHR3 upregulated the transcription of three ecdysteroidogenesis genes (Ldphm, Lddib and Ldshd), increased 20E titer, and activated the expression of two 20E-response genes (LdEcR and LdFTZ-F1). Thus, LdHR3 functions in regulation of pupation in the Colorado potato beetle. PMID:26005119

  3. Target site insensitivity mutations in the AChE enzyme confer resistance to organophosphorous insecticides in Leptinotarsa decemlineata (Say).

    PubMed

    Malekmohammadi, M; Galehdari, H

    2016-01-01

    In the present study, we demonstrated the use and optimization of the tetra-primer ARMS-PCR procedure to detect and analyze the frequency of the R30K and I392T mutations in resistant field populations of CPB. The R30K mutation was detected in 72%, 84%, 52% and 64% of Bahar, Dehpiaz, Aliabad and Yengijeh populations, respectively. Overall frequencies of the I392T mutation were 12%, 8% and 16% of Bahar, Aliabad and Yengijeh populations, respectively. No I392T point mutation was found among samples from Dehpiaz field population. Moreover, only 31% and 2% of samples from the resistant field populations were homozygous for R30K and I392T mutations, respectively. No individual simultaneously had both I392T and S291G/R30K point mutations. The incidence of individuals with both S291G and R30K point mutations in the samples from Bahar, Dehpiaz, Aliabad, and Yengijeh populations were 31.5%, 44.7%, 41.6%, and 27.3% respectively. Genotypes determined by the tetra-primer ARMS-PCR method were consistent with those determined by PCR sequencing. There was no significant correlation between the mutation frequencies and resistance levels in the resistant populations, indicating that other mutations may contribute to this variation. Polymorphism in the partial L. decemlineata cDNA AChE gene Ldace2 of four field populations was identified by direct sequencing of PCR-amplified fragments. Among 45 novel mutations detected in this study, T29P mutation was found across all four field populations that likely contribute to the AChE insensitivity. Site-directed mutagenesis and protein expression experiments are needed for a more complete evaluation. PMID:26778439

  4. Independent action between DvSnf7 RNA and Cry3Bb1 protein in southern corn rootworm, Diabrotica undecimpunctata howardi and Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Levine, Steven L; Tan, Jianguo; Mueller, Geoffrey M; Bachman, Pamela M; Jensen, Peter D; Uffman, Joshua P

    2015-01-01

    In recent years, corn rootworm (CRW)-resistant maize events producing two or more CRW-active Bt proteins have been commercialized to enhance efficacy against the target pest(s) by providing multiple modes of action (MoA). The maize hybrid MON 87411 has been developed that produces the CRW-active Cry3Bb1 Bt protein (hereafter Cry3Bb1) and expresses a RNAi-mediated MoA that also targets CRW. As part of an environmental risk assessment for MON 87411, the potential for an interaction between the CRW-active DvSnf7 RNA (hereafter DvSnf7) and Cry3Bb1 was assessed in 12-day diet incorporation bioassays with the southern corn rootworm (SCR, Diabrotica undecimpunctata howardi). The potential for an interaction between DvSnf7 and Cry3Bb1 was evaluated with two established experimental approaches. The first approach evaluated each substance alone and in combination over three different response levels. For all three response levels, observed responses were shown to be additive and not significantly different from predicted responses under the assumption of independent action. The second approach evaluated the potential for a fixed sub-lethal concentration of Cry3Bb1 to decrease the median lethal concentration (LC50) of DvSnf7 and vice-versa. With this approach, the LC50 value of DvSnf7 was not altered by a sub-lethal concentration of Cry3Bb1 and vice-versa. In addition, the potential for an interaction between the Cry3Bb1 and DvSnf7 was tested with Colorado potato beetle (CPB, Leptinotarsa decemlineata), which is sensitive to Cry3Bb1 but not DvSnf7. CPB assays also demonstrated that DvSnf7 does not alter the activity of Cry3Bb1. The results from this study provide multiple lines of evidence that DvSnf7 and Cry3Bb1 produced in MON 87411 have independent action. PMID:25734482

  5. Independent Action between DvSnf7 RNA and Cry3Bb1 Protein in Southern Corn Rootworm, Diabrotica undecimpunctata howardi and Colorado Potato Beetle, Leptinotarsa decemlineata

    PubMed Central

    Levine, Steven L.; Tan, Jianguo; Mueller, Geoffrey M.; Bachman, Pamela M.; Jensen, Peter D.; Uffman, Joshua P.

    2015-01-01

    In recent years, corn rootworm (CRW)-resistant maize events producing two or more CRW-active Bt proteins have been commercialized to enhance efficacy against the target pest(s) by providing multiple modes of action (MoA). The maize hybrid MON 87411 has been developed that produces the CRW-active Cry3Bb1 Bt protein (hereafter Cry3Bb1) and expresses a RNAi-mediated MoA that also targets CRW. As part of an environmental risk assessment for MON 87411, the potential for an interaction between the CRW-active DvSnf7 RNA (hereafter DvSnf7) and Cry3Bb1 was assessed in 12-day diet incorporation bioassays with the southern corn rootworm (SCR, Diabrotica undecimpunctata howardi). The potential for an interaction between DvSnf7 and Cry3Bb1 was evaluated with two established experimental approaches. The first approach evaluated each substance alone and in combination over three different response levels. For all three response levels, observed responses were shown to be additive and not significantly different from predicted responses under the assumption of independent action. The second approach evaluated the potential for a fixed sub-lethal concentration of Cry3Bb1 to decrease the median lethal concentration (LC50) of DvSnf7 and vice-versa. With this approach, the LC50 value of DvSnf7 was not altered by a sub-lethal concentration of Cry3Bb1 and vice-versa. In addition, the potential for an interaction between the Cry3Bb1 and DvSnf7 was tested with Colorado potato beetle (CPB, Leptinotarsa decemlineata), which is sensitive to Cry3Bb1 but not DvSnf7. CPB assays also demonstrated that DvSnf7 does not alter the activity of Cry3Bb1. The results from this study provide multiple lines of evidence that DvSnf7 and Cry3Bb1 produced in MON 87411 have independent action. PMID:25734482

  6. Independent action between DvSnf7 RNA and Cry3Bb1 protein in southern corn rootworm, Diabrotica undecimpunctata howardi and Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Levine, Steven L; Tan, Jianguo; Mueller, Geoffrey M; Bachman, Pamela M; Jensen, Peter D; Uffman, Joshua P

    2015-01-01

    In recent years, corn rootworm (CRW)-resistant maize events producing two or more CRW-active Bt proteins have been commercialized to enhance efficacy against the target pest(s) by providing multiple modes of action (MoA). The maize hybrid MON 87411 has been developed that produces the CRW-active Cry3Bb1 Bt protein (hereafter Cry3Bb1) and expresses a RNAi-mediated MoA that also targets CRW. As part of an environmental risk assessment for MON 87411, the potential for an interaction between the CRW-active DvSnf7 RNA (hereafter DvSnf7) and Cry3Bb1 was assessed in 12-day diet incorporation bioassays with the southern corn rootworm (SCR, Diabrotica undecimpunctata howardi). The potential for an interaction between DvSnf7 and Cry3Bb1 was evaluated with two established experimental approaches. The first approach evaluated each substance alone and in combination over three different response levels. For all three response levels, observed responses were shown to be additive and not significantly different from predicted responses under the assumption of independent action. The second approach evaluated the potential for a fixed sub-lethal concentration of Cry3Bb1 to decrease the median lethal concentration (LC50) of DvSnf7 and vice-versa. With this approach, the LC50 value of DvSnf7 was not altered by a sub-lethal concentration of Cry3Bb1 and vice-versa. In addition, the potential for an interaction between the Cry3Bb1 and DvSnf7 was tested with Colorado potato beetle (CPB, Leptinotarsa decemlineata), which is sensitive to Cry3Bb1 but not DvSnf7. CPB assays also demonstrated that DvSnf7 does not alter the activity of Cry3Bb1. The results from this study provide multiple lines of evidence that DvSnf7 and Cry3Bb1 produced in MON 87411 have independent action.

  7. Chemical ecology of the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), and emerging control methods using semiochemicals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Colorado potato beetle (CPB) has been a major insect pest of potatoes for over 150 years and various control methods have been established to reduce its impact on potato fields. Pesticide use is currently the most widely used approach, although alternative methods are being developed. Amongst ...

  8. Impact of cell shape in hierarchically structured plant surfaces on the attachment of male Colorado potato beetles (Leptinotarsa decemlineata).

    PubMed

    Prüm, Bettina; Seidel, Robin; Bohn, Holger Florian; Speck, Thomas

    2012-01-01

    Plant surfaces showing hierarchical structuring are frequently found in plant organs such as leaves, petals, fruits and stems. In our study we focus on the level of cell shape and on the level of superimposed microstructuring, leading to hierarchical surfaces if both levels are present. While it has been shown that epicuticular wax crystals and cuticular folds strongly reduce insect attachment, and that smooth papillate epidermal cells in petals improve the grip of pollinators, the impact of hierarchical surface structuring of plant surfaces possessing convex or papillate cells on insect attachment remains unclear. We performed traction experiments with male Colorado potato beetles on nine different plant surfaces with different structures. The selected plant surfaces showed epidermal cells with either tabular, convex or papillate cell shape, covered either with flat films of wax, epicuticular wax crystals or with cuticular folds. On surfaces possessing either superimposed wax crystals or cuticular folds we found traction forces to be almost one order of magnitude lower than on surfaces covered only with flat films of wax. Independent of superimposed microstructures we found that convex and papillate epidermal cell shapes slightly enhance the attachment ability of the beetles. Thus, in plant surfaces, cell shape and superimposed microstructuring yield contrary effects on the attachment of the Colorado potato beetle, with convex or papillate cells enhancing attachment and both wax crystals or cuticular folds reducing attachment. However, the overall magnitude of traction force mainly depends on the presence or absence of superimposed microstructuring. PMID:22428097

  9. Chemical Ecology of the Colorado Potato Beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), and Potential for Alternative Control Methods

    PubMed Central

    Sablon, Ludovic; Dickens, Joseph C.; Haubruge, Éric; Verheggen, François J.

    2012-01-01

    The Colorado potato beetle (CPB) has been a major insect pest to potato farming for over 150 years and various control methods have been established to reduce its impact on potato fields. Crop rotation and pesticide use are currently the most widely used approaches, although alternative methods are being developed. Here we review the role of various volatile and nonvolatile chemicals involved in behavior changes of CPB that may have potential for their control. First, we describe all volatile and nonvolatile chemicals involved in host plant localization and acceptance by CPB beetles, including glycoalcaloids and host plant volatiles used as kairomones. In the second section, we present the chemical signals used by CPB in intraspecific communication, including sex and aggregation pheromones. Some of these chemicals are used by natural enemies of CPBs to locate their prey and are presented in the third section. The last section of this review is devoted a discussion of the potential of some natural chemicals in biological control of CPB and to approaches that already reached efficient field applications. PMID:26466794

  10. Chemical Ecology of the Colorado Potato Beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), and Potential for Alternative Control Methods.

    PubMed

    Sablon, Ludovic; Dickens, Joseph C; Haubruge, Éric; Verheggen, François J

    2012-12-20

    The Colorado potato beetle (CPB) has been a major insect pest to potato farming for over 150 years and various control methods have been established to reduce its impact on potato fields. Crop rotation and pesticide use are currently the most widely used approaches, although alternative methods are being developed. Here we review the role of various volatile and nonvolatile chemicals involved in behavior changes of CPB that may have potential for their control. First, we describe all volatile and nonvolatile chemicals involved in host plant localization and acceptance by CPB beetles, including glycoalcaloids and host plant volatiles used as kairomones. In the second section, we present the chemical signals used by CPB in intraspecific communication, including sex and aggregation pheromones. Some of these chemicals are used by natural enemies of CPBs to locate their prey and are presented in the third section. The last section of this review is devoted a discussion of the potential of some natural chemicals in biological control of CPB and to approaches that already reached efficient field applications.

  11. The effect of mode of exposure to Beauveria bassiana on conidia acquisition and host mortality of Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Fernandez, S; Groden, E; Vandenberg, J D; Furlong, M J

    2001-04-01

    The effects of the mode of exposure of second instar Colorado potato beetles to Beauveria bassiana on conidia acquisition and resulting mortality were investigated in laboratory studies. Larvae sprayed directly with a B. bassiana condial suspension, larvae exposed to B. bassiana-treated foliage, and larvae both sprayed and exposed to treated foliage experienced 76, 34, and 77% mortality, respectively. The total number of conidia and the proportion of germinating conidia were measured over time for four sections of the insect body: the ventral surface of the head (consisting mostly of ventral mouth parts), the ventral abdominal surface, the dorsal abdominal surface, and the legs. From observations at 24 and 36 h posttreatment, mean totals of 161.1 conidia per insect were found on sprayed larvae, 256.1 conidia on larvae exposed only to treated foliage, and 408.3 conidia on larvae both sprayed and exposed to treated foliage. On sprayed larvae, the majority of conidia were found on the dorsal abdominal surface, whereas conidia were predominantly found in the ventral abdominal surface and mouth parts on larvae exposed to treated foliage. Between 24 and 36 h postinoculation the percentage of conidia germinating on sprayed larvae increased slightly from 80 to 84%). On the treated foliage, the percentage of germinated conidia on larvae increased from 35% at 24 h to 50% at 36 h posttreatment. Conidia germination on sprayed larvae on treated foliage was 65% at 24 h and 75% at 36 h posttreatment. It is likely that the gradual acquisition of conidia derived from the continuous exposure to B. bassiana inoculum on the foliar surface was responsible for the increase in germination over time on larvae exposed to treated foliage. The density and germination of conidia were observed 0, 4, 8, 12, 16, 20, and 24 h after being sprayed with or dipped in conidia suspensions or exposing insects to contaminated foliage. Conidia germinated twice as fast on sprayed insects as with any other

  12. Potato, Solanum tuberosum, defense against Colorado potato beetle, Leptinotarsa decemlineata (Say): microarray gene expression profiling of potato by Colorado potato beetle regurgitant treatment of wounded leaves.

    PubMed

    Lawrence, Susan D; Novak, Nicole G; Ju, Chelsea J-T; Cooke, Janice E K

    2008-08-01

    Colorado potato beetle (CPB) is a leading pest of solanaceous plants. Despite the economic importance of this pest, surprisingly few studies have been carried out to characterize its molecular interaction with the potato plant. In particular, little is known about the effect of CPB elicitors on gene expression associated with the plant's defense response. In order to discover putative CPB elicitor-responsive genes, the TIGR 11,421 EST Solanaceae microarray was used to identify genes that are differentially expressed in response to the addition of CPB regurgitant to wounded potato leaves. By applying a cutoff corresponding to an adjusted P-value of <0.01 and a fold change of >1.5 or <0.67, we found that 73 of these genes are induced by regurgitant treatment of wounded leaves when compared to wounding alone, whereas 54 genes are repressed by this treatment. This gene set likely includes regurgitant-responsive genes as well as wounding-responsive genes whose expression patterns are further enhanced by the presence of regurgitant. Real-time polymerase chain reaction was used to validate differential expression by regurgitant treatment for five of these genes. In general, genes that encoded proteins involved in secondary metabolism and stress were induced by regurgitant; genes associated with photosynthesis were repressed. One induced gene that encodes aromatic amino acid decarboxylase is responsible for synthesis of the precursor of 2-phenylethanol. This is significant because 2-phenylethanol is recognized by the CPB predator Perillus bioculatis. In addition, three of the 16 type 1 and type 2 proteinase inhibitor clones present on the potato microarray were repressed by application of CPB regurgitant to wounded leaves. Given that proteinase inhibitors are known to interfere with digestion of proteins in the insect midgut, repression of these proteinase inhibitors by CPB may inhibit this component of the plant's defense arsenal. These data suggest that beyond the wound

  13. Physiological roles of trehalose in Leptinotarsa larvae revealed by RNA interference of trehalose-6-phosphate synthase and trehalase genes.

    PubMed

    Shi, Ji-Feng; Xu, Qing-Yu; Sun, Qiang-Kun; Meng, Qing-Wei; Mu, Li-Li; Guo, Wen-Chao; Li, Guo-Qing

    2016-10-01

    Trehalose is proposed to serve multiple physiological roles in insects. However, its importance remains largely unconfirmed. In the present paper, we knocked down either a trehalose biosynthesis gene (trehalose-6-phosphate synthase, LdTPS) or each of three degradation genes (soluble trehalases LdTRE1a, LdTRE1b or membrane-bound LdTRE2) in Leptinotarsa decemlineata by RNA interference (RNAi). Knockdown of LdTPS decreased trehalose content and caused larval and pupal lethality. The LdTPS RNAi survivors consumed a greater amount of foliage, obtained a heavier body mass, accumulated more glycogen, lipid and proline, and had a smaller amount of chitin compared with the controls. Ingestion of trehalose but not glucose rescued the food consumption increase and larval mass rise, increased survivorship, and recovered glycogen, lipid and chitin to the normal levels. In contrast, silencing of LdTRE1a increased trehalose content and resulted in larval and pupal lethality. The surviving LdTRE1a RNAi hypomorphs fed a smaller quantity of food, had a lighter body weight, depleted lipid and several glucogenic amino acids, and contained a smaller amount of chitin. Neither trehalose nor glucose ingestion rescued these LdTRE1a RNAi defects. Silencing of LdTRE1b caused little effects. Knockdown of LdTRE2 caused larval death, increased trehalose contents in several tissues and diminished glycogen in the brain-corpora cardiaca-corpora allata complex (BCC). Feeding glucose but not trehalose partially rescued the high mortality rate and recovered glycogen content in the BCC. It seems that trehalose is involved in feeding regulation, sugar absorption, brain energy supply and chitin biosynthesis in L. decemlineata larvae. PMID:27524277

  14. Two Leptinotarsa uridine diphosphate N-acetylglucosamine pyrophosphorylases are specialized for chitin synthesis in larval epidermal cuticle and midgut peritrophic matrix.

    PubMed

    Shi, Ji-Feng; Fu, Jia; Mu, Li-Li; Guo, Wen-Chao; Li, Guo-Qing

    2016-01-01

    Uridine diphosphate-N-acetylglucosamine-pyrophosphorylase (UAP) is involved in the biosynthesis of chitin, an essential component of the epidermal cuticle and midgut peritrophic matrix (PM) in insects. In the present paper, two putative LdUAP genes were cloned in Leptinotarsa decemlineata. In vivo bioassay revealed that 20-hydroxyecdysone (20E) and an ecdysteroid agonist halofenozide activated the expression of the two LdUAPs, whereas a decrease in 20E by RNA interference (RNAi) of an ecdysteroidogenesis gene LdSHD and a 20E signaling gene LdFTZ-F1 repressed the expression. Juvenile hormone (JH), a JH analog pyriproxyfen and an increase in JH by RNAi of an allatostatin gene LdAS-C downregulated LdUAP1 but upregulated LdUAP2, whereas a decrease in JH by silencing of a JH biosynthesis gene LdJHAMT had converse effects. Thus, expression of LdUAPs responded to both 20E and JH. Moreover, knockdown of LdUAP1 reduced chitin contents in whole larvae and integument samples, thinned tracheal taenidia, impaired larval-larval molt, larval-pupal ecdysis and adult emergence. In contrast, silencing of LdUAP2 significantly reduced foliage consumption, decreased chitin content in midgut samples, damaged PM, and retarded larval growth. The resulting larvae had lighter fresh weights, smaller body sizes and depleted fat body. As a result, the development was arrested. Combined knockdown of LdUAP1 and LdUAP2 caused an additive negative effect. Our data suggest that LdUAP1 and LdUAP2 have specialized functions in biosynthesizing chitin in the epidermal cuticle and PM respectively in L. decemlineata. PMID:26592348

  15. Reduced stability and intracellular transport of dsRNA contribute to poor RNAi response in lepidopteran insects.

    PubMed

    Shukla, Jayendra Nath; Kalsi, Megha; Sethi, Amit; Narva, Kenneth E; Fishilevich, Elane; Singh, Satnam; Mogilicherla, Kanakachari; Palli, Subba Reddy

    2016-07-01

    RNA interference (RNAi) has become a widely used reverse genetic tool to study gene function in eukaryotic organisms and is being developed as a technology for insect pest management. The efficiency of RNAi varies among organisms. Insects from different orders also display differential efficiency of RNAi, ranging from highly efficient (coleopterans) to very low efficient (lepidopterans). We investigated the reasons for varying RNAi efficiency between lepidopteran and coleopteran cell lines and also between the Colorado potato beetle, Leptinotarsa decemlineata and tobacco budworm, Heliothis virescens. The dsRNA either injected or fed was degraded faster in H. virescens than in L. decemlineata. Both lepidopteran and coleopteran cell lines and tissues efficiently took up the dsRNA. Interestingly, the dsRNA administered to coleopteran cell lines and tissues was taken up and processed to siRNA whereas the dsRNA was taken up by lepidopteran cell lines and tissues but no siRNA was detected in the total RNA isolated from these cell lines and tissues. The data included in this paper showed that the degradation and intracellular transport of dsRNA are the major factors responsible for reduced RNAi efficiency in lepidopteran insects. PMID:27245473

  16. Reduced stability and intracellular transport of dsRNA contribute to poor RNAi response in lepidopteran insects

    PubMed Central

    Shukla, Jayendra Nath; Kalsi, Megha; Sethi, Amit; Narva, Kenneth E.; Fishilevich, Elane; Singh, Satnam; Mogilicherla, Kanakachari; Palli, Subba Reddy

    2016-01-01

    ABSTRACT RNA interference (RNAi) has become a widely used reverse genetic tool to study gene function in eukaryotic organisms and is being developed as a technology for insect pest management. The efficiency of RNAi varies among organisms. Insects from different orders also display differential efficiency of RNAi, ranging from highly efficient (coleopterans) to very low efficient (lepidopterans). We investigated the reasons for varying RNAi efficiency between lepidopteran and coleopteran cell lines and also between the Colorado potato beetle, Leptinotarsa decemlineata and tobacco budworm, Heliothis virescens. The dsRNA either injected or fed was degraded faster in H. virescens than in L. decemlineata. Both lepidopteran and coleopteran cell lines and tissues efficiently took up the dsRNA. Interestingly, the dsRNA administered to coleopteran cell lines and tissues was taken up and processed to siRNA whereas the dsRNA was taken up by lepidopteran cell lines and tissues but no siRNA was detected in the total RNA isolated from these cell lines and tissues. The data included in this paper showed that the degradation and intracellular transport of dsRNA are the major factors responsible for reduced RNAi efficiency in lepidopteran insects. PMID:27245473

  17. Evaluation of tag entanglement as a factor in harmonic radar studies of insect dispersal.

    PubMed

    Boiteau, G; Vincent, C; Meloche, F; Leskey, T C; Colpitts, B G

    2011-02-01

    The observation of insects and other small organisms entangled in the habitat after the addition of vertical or trailing electronic tags to their body has generated concerns on the suitability of harmonic radars to track the dispersal of insects. This study compared the walking behavior of adult Colorado potato beetle (Leptinotarsa decemlineata (Say) Chrysomelidae), plum curculio (Conotrachelus nenuphar (Herbst) Curculionidae), and western corn rootworm (Diabrotica virgifera virgifera (LeConte) Chrysomelidae) with and without vertical and or trailing tags in field plots or arenas. The frequency of the larger Colorado potato beetles crossing bare ground or grassy plots was unaffected by the presence of an 8 cm trailing harmonic radar tag. However, plum curculios and western corn rootworms, were either unable to walk with a 4 cm trailing tag (plum curculio) or displayed a reduced ability to successfully cross a bare ground arena. Our results revealed the significant impact of vegetation on successful insect dispersal, whether tagged or not. The vertical movement of these insects on stems, stalks, and tubes was also unaffected by the presence of vertical tags. Trailing tags had a significant negative effect on the vertical movement of the western corn rootworm. Results show that harmonic radar technology is a suitable method for studying the walking paths of the three insects with appropriate tag type and size. The nuisance factor generated by appropriately sized tags was small relative to that of vegetation. PMID:22182617

  18. The insect abdomen--a heartbeat manager in insects?

    PubMed

    Tartes, U; Vanatoa, A; Kuusik, A

    2002-11-01

    Different possibilities of coordination between circulation, respiration and abdominal movements were found in pupae of Pieris brassicae, Tenebrio molitor, Galleria mellonella and Leptinotarsa decemlineata. Coordination principles depend on metabolic rate: the need to support circulation with abdominal movements appears only at higher metabolic rates. Integration between different abdominal movements and circulation depends on species, on physiological state and, supposedly, on internal morphology. At low metabolic rates, there is no need for a very intensive hemolymph flow, and the dorsal vessel is capable of initiating and/or maintaining necessary hemolymph flow. Starting from a certain metabolic level, it is possible that the abdomen is used to accelerate hemolymph flow in the case of a large amount of hemolymph. When the necessary flow speed has been reached, relatively weak pulsation of the dorsal vessel with accessory pulsatile organs and diaphragms can easily maintain the necessary flow intensity. Heart activity may sometimes be initiated by abdominal movements via cardiac reflex or mechanical excitation. Sometimes, when heart function is weakened by histolysis, the abdomen may temporarily take over the main circulatory function or occasionally contribute to acceleration of low-speed hemolymph flow. In this case the functions are simultaneous and may be triggered by some mediator(s). In active adult insects the whole body is moving, and hence hemolymph circulates and the tracheal system is effectively ventilated by a whole body ensemble consisting of the dorsal vessel, moving organs, body appendages and accessory pulsatile organs. The mechanism of autocirculation (analogous to autoventilation in gas exchange) is a probable mechanism in circulation in adult insects. PMID:12443919

  19. Monitoring diapause development in the Colorado potato beetle, Leptinotarsa decemlineata, under field conditions using molecular biomarkers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A multiplex PCR protocol was developed using five diapause-regulated genes to monitor diapause development of the Colorado potato beetle under field conditions. A total of 870 beetles from the Red River Valley of North Dakota and Minnesota, USA, were screened for three consecutive years. Out of the ...

  20. Monitoring diapause development in the Colorado potato beetle, Leptinotarsa decemlineata, under field conditions using molecular biomarkers.

    PubMed

    Yocum, George D; Rinehart, Joseph P; Larson, Marnie L

    2011-05-01

    A multiplex PCR protocol was developed using five diapause-regulated genes to monitor diapause development of the Colorado potato beetle under field conditions. A total of 870 beetles from the Red River valley of North Dakota and Minnesota, USA, were screened for three consecutive years. Out of the 32 possible expression profiles, eight could be arranged in chronological order of diapause development. These eight profiles account for over 92% of the beetles surveyed. Intra-population variation in diapause phenotypes was observed in the field. Some beetles were already in the diapause initiation phase in June when the day length was greater than 17 h. Inter-seasonal variation in the timing of diapause development was also noted. The greatest differences were before the day length decreased to less than 15 h. Anomalies in the results, e.g., the presence of the diapause maintenance phase profiles in beetles collected on the potato plants, argue that laboratory results are not always equivalent with what is observed under field conditions.

  1. Inhibition of insect glutathione S-transferase (GST) by conifer extracts.

    PubMed

    Wang, Zhiling; Zhao, Zhong; Abou-Zaid, Mamdouh M; Arnason, John T; Liu, Rui; Walshe-Roussel, Brendan; Waye, Andrew; Liu, Suqi; Saleem, Ammar; Cáceres, Luis A; Wei, Qin; Scott, Ian M

    2014-12-01

    Insecticide synergists biochemically inhibit insect metabolic enzyme activity and are used both to increase the effectiveness of insecticides and as a diagnostic tool for resistance mechanisms. Considerable attention has been focused on identifying new synergists from phytochemicals with recognized biological activities, specifically enzyme inhibition. Jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana (Mill.) BSP.), balsam fir (Abies balsamea (L.) Mill.), and tamarack larch (Larix laricina (Du Roi) Koch) have been used by native Canadians as traditional medicine, specifically for the anti-inflammatory and antioxidant properties based on enzyme inhibitory activity. To identify the potential allelochemicals with synergistic activity, ethanol crude extracts and methanol/water fractions were separated by Sephadex LH-20 chromatographic column and tested for in vitro glutathione S-transferase (GST) inhibition activity using insecticide-resistant Colorado potato beetle, Leptinotarsa decemlineata (Say) midgut and fat-body homogenate. The fractions showing similar activity were combined and analyzed by ultra pressure liquid chromatography-mass spectrometry. A lignan, (+)-lariciresinol 9'-p-coumarate, was identified from P. mariana cone extracts, and L. laricina and A. balsamea bark extracts. A flavonoid, taxifolin, was identified from P. mariana and P. banksiana cone extracts and L. laricina bark extracts. Both compounds inhibit GST activity with taxifolin showing greater activity compared to (+)-lariciresinol 9'-p-coumarate and the standard GST inhibitor, diethyl maleate. The results suggested that these compounds can be considered as potential new insecticide synergists. PMID:25270601

  2. Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests.

    PubMed

    Scott, I M; Jensen, H; Nicol, R; Lesage, L; Bradbury, R; Sánchez-Vindas, P; Poveda, L; Arnason, J T; Philogène, B J R

    2004-08-01

    Extracts from three species of the plant family Piperaceae, Piper nigrum [L.], Piper guineense [Schum & Thonn, and Piper tuberculatum [Jacq.], were tested for efficacy against insects from five orders. All three species contain isobutyl amides, plant secondary compounds that act as neurotoxins in insects. These materials are considered safe to mammals because Piper spp. were used for centuries for spice and medicinal purposes. When 24-h P. nigrum LC50 values were compared between common insect pests from eastern Canada and the northeastern United States, the most sensitive species in order of increasing lethal concentration were eastern tent caterpillar, Malacosoma americanum (F.) < European pine sawfly larvae, Neodiprion sertifer (Geoffroy) < spindle ermine moth larvae, Yponomeuta cagnagella [Hübner] < viburnum leaf beetle larvae, Pyrrhalta viburni [Paykull] < stripped cucumber beetle adults, Acalymma vittatum (F.) < Colorado potato beetle adults, Leptinotarsa decemlineata (Say) < Japanese beetle adults, Popillia japonica [Newman] < hairy chinch bug, Blissus leucopterus hirtis [Montandon]. The life stage tested was the point at which each species causes the greatest amount of damage to the host plant and the point at which most gardeners would likely choose to treat with a conventional synthetic insecticide. Greenhouse trials revealed that the pepper formulations also had a repellent activity, thus protecting plant leaves from 1) herbivory (lily leaf beetle, Lilioceris lilii [Scopoli], adults and larvae and stripped cucumber beetle adults) and 2) oviposition [European corn borer, Ostrinia nubilalis (Hübner)]. Combinations with other botanical extracts were additive at best in toxicity and repellent trials. Nontarget toxicity to beneficial invertebrates is a possibility because the P. nigrum LC50 for beneficial ladybird beetles was 0.2%. P. nigrum extracts can provide a reasonable level of control against lepidopteran and European pine sawfly larvae and also will

  3. Prey perception of predation risk: volatile chemical cues mediate non-consumptive effects of a predator on a herbivorous insect.

    PubMed

    Hermann, Sara L; Thaler, Jennifer S

    2014-11-01

    Predators can affect prey in two ways-by reducing their density (consumptive effects) or by changing their behavior, physiology or other phenotypic traits (non-consumptive effects). Understanding the cues and sensory modalities prey use to detect predators is critical for predicting the strength of non-consumptive effects and the outcome of predator-prey encounters. While predator-associated cues have been well studied in aquatic systems, less is known about how terrestrial prey, particularly insect larvae, detect their predators. We evaluated how Colorado potato beetle, Leptinotarsa decemlineata, larvae perceive predation risk by isolating cues from its stink bug predator, the spined soldier bug, Podisus maculiventris. When exposed to male "risk" predators that were surgically manipulated so they could hunt but not kill, beetles reduced feeding 29% compared to controls. Exposure to risk females caused an intermediate response. Beetles ate 24% less on leaves pre-exposed to predators compared to leaves never exposed to predators, indicating that tactile and visual cues are not required for the prey's response. Volatile odor cues from predators reduced beetle feeding by 10% overall, although male predators caused a stronger reduction than females. Finally, visual cues from the predator had a weak effect on beetle feeding. Because multiple cues appear to be involved in prey perception of risk, and because male and female predators have differential effects, beetle larvae likely experience tremendous variation in the information about risk from their local environment. PMID:25234373

  4. Molecular interactions between an insect predator and its herbivore prey on transgenic potato expressing a cysteine proteinase inhibitor from rice.

    PubMed

    Bouchard, Edith; Michaud, Dominique; Cloutier, Conrad

    2003-09-01

    Transgenic plants expressing resistance to herbivorous insects may represent a safe and sustainable pest control alternative if they do not interfere with the natural enemies of target pests. Here we examined interactions between oryzacystatin I (OCI), a proteinase inhibitor from rice genetically engineered into potato (Solanum tuberosum cv. Kennebec, line K52) to increase resistance to insect herbivory, and the insect predator Perillus bioculatus. This stinkbug is a relatively specialized predator of caterpillars and leaf-beetle larvae, and may also include plant sap in its predominantly carnivorous diet. One of its preferred prey is Colorado potato beetle (Leptinotarsa decemlineata), a major target of insect resistance development for potato field crops. Gelatin/sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that a major fraction of proteinase (gelatinase) activity in P. bioculatus extracts is OCI-sensitive. Among five gelatinolytic bands detected, the slowest-moving one (proteinase I) was inhibited strongly by purified OCI expressed in Escherichia coli or by OCI-transgenic potato extracts, while three other proteinases were partly sensitive to these treatments. There was also evidence of slight inhibition of proteinase I by untransformed potato foliage, suggesting the presence of a natural inhibitor related to OCI at low level in potato foliage. Interestingly, only about 50% of the maximum potential activity of proteinase I was recovered in extracts of P. bioculatus feeding on L. decemlineata larval prey on a diet of OCI-potato foliage, indicating that the predator was sensitive to OCI in the midgut of its prey. However, P. bioculatus on OCI-prey survived, grew and developed normally, indicating ability to compensate prey-mediated exposure to the OCI inhibitor. Confinement of P. bioculatus to potato foliage provided no evidence that potato plant-derived nutrition is a viable alternative to predation, restriction to potato foliage

  5. Immunocytochemical localization in the central nervous system of four different insect species of molecules immunoreactive against peptides present in the caudodorsal cells of Lymnaea stagnalis.

    PubMed

    Theunis, W; Van Minnen, J; De Loof, A

    1990-09-01

    The use of polyclonal antisera directed against three peptides (ovulation hormone (CDCH), alpha, and beta caudodorsal cell peptide (alpha- and beta-CDCP) produced by the caudodorsal cells of the snail Lymnaea stagnalis resulted in positive immunoreaction in Sarcophaga bullata (Diptera), Leptinotarsa decemlineata (Coleoptera), Locusta migratoria, and Periplaneta americana (Orthoptera). In three species, colocalization was detected using the antisera against CDCH and alpha-CDCP.

  6. Single substitutions to closely related amino acids contribute to the functional diversification of an insect-inducible, positively selected plant cystatin.

    PubMed

    Rasoolizadeh, Asieh; Goulet, Marie-Claire; Sainsbury, Frank; Cloutier, Conrad; Michaud, Dominique

    2016-04-01

    A causal link has been reported between positively selected amino acids in plant cystatins and the inhibitory range of these proteins against insect digestive cysteine (Cys) proteases. Here we assessed the impact of single substitutions to closely related amino acids on the contribution of positive selection to cystatin diversification. Cystatin sequence alignments, while confirming hypervariability, indicated a preference for related amino acids at positively selected sites. For example, the non-polar residues leucine (Leu), isoleucine (Ile) and valine (Val) were shown to predominate at positively selected site 2 in the N-terminal region, unlike selected sites 6 and 10, where polar residues are preferred. The model cystatin SlCYS8 and single variants with Leu, Ile or Val at position 2 were compared with regard to their ability to bind digestive proteases of the coleopteran pest Leptinotarsa decemlineata and to induce compensatory responses in this insect. A functional proteomics procedure to capture target Cys proteases in midgut extracts allowed confirmation of distinct binding profiles for the cystatin variants. A shotgun proteomics procedure to monitor whole Cys protease complements revealed protease family specific compensatory responses in the insect, dependent on the variant ingested. Our data confirm the contribution of closely related amino acids to the functional diversity of positively selected plant cystatins in a broader structure/function context imposing physicochemical constraints to primary structure alterations. They also underline the complexity of protease/inhibitor interactions in plant-insect systems, and the challenges still to be met in order to harness the full potential of ectopically expressed protease inhibitors in crop protection.

  7. Plant Defenses and Predation Risk Differentially Shape Patterns of Consumption, Growth, and Digestive Efficiency in a Guild of Leaf-Chewing Insects

    PubMed Central

    Kaplan, Ian; McArt, Scott H.; Thaler, Jennifer S.

    2014-01-01

    Herbivores are squeezed between the two omnipresent threats of variable food quality and natural enemy attack, but these two factors are not independent of one another. The mechanisms by which organisms navigate the dual challenges of foraging while avoiding predation are poorly understood. We tested the effects of plant defense and predation risk on herbivory in an assemblage of leaf-chewing insects on Solanum lycopersicum (tomato) that included two Solanaceae specialists (Manduca sexta and Leptinotarsa decemlineata) and one generalist (Trichoplusia ni). Defenses were altered using genetic manipulations of the jasmonate phytohormonal cascade, whereas predation risk was assessed by exposing herbivores to cues from the predaceous stink bug, Podisus maculiventris. Predation risk reduced herbivore food intake by an average of 29% relative to predator-free controls. Interestingly, this predator-mediated impact on foraging behavior largely attenuated when quantified in terms of individual growth rate. Only one of the three species experienced lower body weight under predation risk and the magnitude of this effect was small (17% reduction) compared with effects on foraging behavior. Manduca sexta larvae, compensated for their predator-induced reduction in food intake by more effectively converting leaf tissue to body mass. They also had higher whole-body lipid content when exposed to predators, suggesting that individuals convert energy to storage forms to draw upon when risk subsides. In accordance with expectations based on insect diet breadth, plant defenses tended to have a stronger impact on consumption and growth in the generalist than the two specialists. These data both confirm the ecological significance of predators in the foraging behavior of herbivorous prey and demonstrate how sophisticated compensatory mechanisms allow foragers to partially offset the detrimental effects of reduced food intake. The fact that these mechanisms operated across a wide range of

  8. Comparative ecophysiology of cold-tolerance-related traits: assessing range expansion potential for an invasive insect at high latitude.

    PubMed

    Lehmann, Philipp; Kaunisto, Sirpa; Koštál, Vladimir; Margus, Aigi; Zahradníčková, Helena; Lindström, Leena

    2015-01-01

    Survival at high latitude requires the capability to cope with seasonally imposed stress, such as low winter temperatures or large temperature fluctuations. The Colorado potato beetle, Leptinotarsa decemlineata, is an invasive pest of potato that has rapidly spread from low latitudes to higher latitudes. During the last 30 years, a decrease in range expansion speed is apparent in Europe. We use a comparative approach to assess whether this could be due to an inability of L. decemlineata to cope with the harsher winters encountered at high latitude, when compared to two native northern chrysomelid beetles with similar overwintering ecology. We investigated several cold-tolerance-related physiological traits at different time points during winter. Cold tolerance followed a latitudinal pattern; the northern species were more tolerant to short-term subzero temperatures than the invasive L. decemlineata. The other northern species, the knotgrass leaf beetle, Chrysolina polita, was found to tolerate internal freezing. Interestingly, the pattern for overwinter survival at 5°C was the opposite and higher in L. decemlineata than the northern species and could be related to behavioral differences between species in overwintering location selection and a potential physiological trade-off between tolerance to cold shock and to chronic cold exposure. Furthermore, while the northern species accumulated large amounts of different sugars and polyols with probable cryoprotectant functions, none were detected in L. decemlineata at high concentrations. This lack of cryoprotectant accumulation could explain the difference in cold tolerance between the species and also suggests that a lack of physiological capacity to tolerate low temperatures could slow further latitudinal range expansion of L. decemlineata. PMID:25860825

  9. Comparative ecophysiology of cold-tolerance-related traits: assessing range expansion potential for an invasive insect at high latitude.

    PubMed

    Lehmann, Philipp; Kaunisto, Sirpa; Koštál, Vladimir; Margus, Aigi; Zahradníčková, Helena; Lindström, Leena

    2015-01-01

    Survival at high latitude requires the capability to cope with seasonally imposed stress, such as low winter temperatures or large temperature fluctuations. The Colorado potato beetle, Leptinotarsa decemlineata, is an invasive pest of potato that has rapidly spread from low latitudes to higher latitudes. During the last 30 years, a decrease in range expansion speed is apparent in Europe. We use a comparative approach to assess whether this could be due to an inability of L. decemlineata to cope with the harsher winters encountered at high latitude, when compared to two native northern chrysomelid beetles with similar overwintering ecology. We investigated several cold-tolerance-related physiological traits at different time points during winter. Cold tolerance followed a latitudinal pattern; the northern species were more tolerant to short-term subzero temperatures than the invasive L. decemlineata. The other northern species, the knotgrass leaf beetle, Chrysolina polita, was found to tolerate internal freezing. Interestingly, the pattern for overwinter survival at 5°C was the opposite and higher in L. decemlineata than the northern species and could be related to behavioral differences between species in overwintering location selection and a potential physiological trade-off between tolerance to cold shock and to chronic cold exposure. Furthermore, while the northern species accumulated large amounts of different sugars and polyols with probable cryoprotectant functions, none were detected in L. decemlineata at high concentrations. This lack of cryoprotectant accumulation could explain the difference in cold tolerance between the species and also suggests that a lack of physiological capacity to tolerate low temperatures could slow further latitudinal range expansion of L. decemlineata.

  10. Emissive color preferences and temporal alteration of walking performance by pulsing lights in colorado potato beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Colorado potato beetle (CPB) Leptinotarsa decemlineata (Say 1824) is a diurnal insect that strongly relies on vision to guide its walk. In the present study, we investigated the orientation behavior of nondiapausing walking CPB in response to emissive colors produced by light emitting diodes (L...

  11. Harmonic radar: assessing the impact of tag weight on walking behavior of Colorado potato beetle, plum curculio and corn rootworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of electronic dipole tags on the walking behavior of three insects was determined using video tracking software. Results varied within and between the three species studied. The mean horizontal speed of the Colorado potato beetle, Leptinotarsa decemlineata (Say), was reduced by 8 percen...

  12. Insertion of miniature subterminal inverted repeat-like elements in diapause-regulated genes in the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Determining the genomic structure of diapause-associated transcripts (DAT) -2 and -3 led to the isolation of four novel miniature subterminal inverted repeat-like elements (MSITE): Mild-1, -2, -3 and -4. Mild-1a is inserted within the first intron of diapause protein-1. Mild-1a is 284 bp in length, ...

  13. Observing Insects.

    ERIC Educational Resources Information Center

    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)

  14. Antifeedant activity of fatty acid esters and phytosterols from Echium wildpretii.

    PubMed

    Santana, Omar; Reina, Matias; Fraga, Braulio M; Sanz, Jesús; González-Coloma, Azucena

    2012-03-01

    Crude extracts and fractions from Echium wildpretii H. Pearson ex Hook. f. subsp. wildpretii (Boraginaceae) have been tested against insect species Spodoptera littoralis, Leptinotarsa decemlineata, and the aphids Myzus persicae, Diuraphis noxia, Metopolophium dirhodum, Rhopalosiphum maidis, and Rhopalosiphum padi. The EtOH extract and the lipid and steroidal fractions of E. wildpretii exhibited significant antifeedant activities against the aphids and L. decemlineata. Two bioactive mixtures composed of fatty acid esters and n-alkanes were obtained from the lipid fraction. The bioguided fractionation of the steroidal fraction resulted in the isolation of glutinol, β-sitosterol, (3β,7α)-stigmast-5-ene-3,7-diol, and (3β,7α)-7-methoxystigmast-5-en-3-ol. The latter two compounds exhibited potent antifeedant activities against L. decemlineata indicating that the presence of an O-bearing C(7) was responsible for the activities of these molecules.

  15. Stress for invasion success? Temperature stress of preceding generations modifies the response to insecticide stress in an invasive pest insect.

    PubMed

    Piiroinen, Saija; Lyytinen, Anne; Lindström, Leena

    2013-02-01

    Adaptation to stressful environments is one important factor influencing species invasion success. Tolerance to one stress may be complicated by exposure to other stressors experienced by the preceding generations. We studied whether parental temperature stress affects tolerance to insecticide in the invasive Colorado potato beetle Leptinotarsa decemlineata. Field-collected pyrethroid-resistant beetles were reared under either stressful (17°C) or favourable (23°C) insecticide-free environments for three generations. Then, larvae were exposed to pyrethroid insecticides in common garden conditions (23°C). Beetles were in general tolerant to stress. The parental temperature stress alone affected beetles positively (increased adult weight) but it impaired their tolerance to insecticide exposure. In contrast, offspring from the favourable temperature regime showed compensatory weight gain in response to insecticide exposure. Our study emphasizes the potential of cross-generational effects modifying species stress tolerance. When resistant pest populations invade benign environments, a re-application of insecticides may enhance their performance via hormetic effects. In turn, opposite effects may arise if parental generations have been exposed to temperature stress. Thus, the outcome of management practices of invasive pest species is difficult to predict unless we also incorporate knowledge of the evolutionary and recent (preceding generations) stress history of the given populations into pest management. PMID:23467574

  16. Insect Allergy.

    PubMed

    Lee, Hobart; Halverson, Sara; Mackey, Regina

    2016-09-01

    Insect bites and stings are common. Risk factors are mostly associated with environmental exposure. Most insect bites and stings result in mild, local, allergic reactions. Large local reactions and systemic reactions like anaphylaxis are possible. Common insects that bite or sting include mosquitoes, ticks, flies, fleas, biting midges, bees, and wasps. The diagnosis is made clinically. Identification of the insect should occur when possible. Management is usually supportive. For anaphylaxis, patients should be given epinephrine and transported to the emergency department for further evaluation. Venom immunotherapy (VIT) has several different protocols. VIT is highly effective in reducing systemic reactions and anaphylaxis.

  17. Insect Allergy.

    PubMed

    Lee, Hobart; Halverson, Sara; Mackey, Regina

    2016-09-01

    Insect bites and stings are common. Risk factors are mostly associated with environmental exposure. Most insect bites and stings result in mild, local, allergic reactions. Large local reactions and systemic reactions like anaphylaxis are possible. Common insects that bite or sting include mosquitoes, ticks, flies, fleas, biting midges, bees, and wasps. The diagnosis is made clinically. Identification of the insect should occur when possible. Management is usually supportive. For anaphylaxis, patients should be given epinephrine and transported to the emergency department for further evaluation. Venom immunotherapy (VIT) has several different protocols. VIT is highly effective in reducing systemic reactions and anaphylaxis. PMID:27545732

  18. Insect Keepers

    ERIC Educational Resources Information Center

    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. Incredible Insects.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1989-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. Contents are organized into the following sections: (1) "What Makes an Insect an Insect?," including…

  20. Insect phylogenomics.

    PubMed

    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.

  1. The complete mitochondrial genome of the boky-boky, Mungotictis decemlineata, the first representative of the Malagasy carnivores (Mammalia, Carnivora, Eupleridae).

    PubMed

    Hassanin, Alexandre; Veron, Géraldine

    2016-01-01

    The complete mitochondrial genome of the boky-boky, Mungotictis decemlineata, was sequenced using overlapping PCRs. The genome is 16,910 base pairs in length and contains the 37 genes found in a typical mammalian genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The overall base composition on the L-strand is A: 32.1%, C: 27.8%, G: 14.5%, T: 25.6%. The control region of M. decemlineata includes both RS2 and RS3 tandem repeats.

  2. Insect Phylogenomics

    PubMed Central

    Behura, Susanta K.

    2015-01-01

    With the advent of next-generation sequencing methods, phylogenetics has taken a new turn in the recent years. Phylogenomics, the integration of phylogenetics with genome data, has emerged as a powerful approach to study systematics and evolution of species. Recently, breakthrough researches employing phylogenomic tools have provided better insights into the timing and pattern of insect evolution. The 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. Phylogenomic investigations help us better understand systematic and evolutionary relationships of insect species that play important roles as herbivores, predators, detritivores, pollinators, or 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. PMID:25963452

  3. Antifeedant C20 diterpene alkaloids.

    PubMed

    González-Coloma, Azucena; Reina, Matías; Guadaño, Ana; Martínez-Díaz, Rafael; Díaz, Jesús G; García-Rodriguez, Juan; Alva, Allenger; Grandez, Maritza

    2004-09-01

    We have tested the insect antifeedant and toxic activity of 21 C20 diterpenoid alkaloids on Spodoptera littoralis and Leptinotarsa decemlineata. The antifeedant effects of the test compounds were structure- and species-dependent. The most active antifeedants to L. decemlineata and S. littoralis were the rearranged form of hetisine (20; EC50 = 1.7 microg/cm2) and 19-oxodihydroatisine (9; EC50 = 0.1 microg/cm2), resp. Glandulosine (8) moderately affected orally injected S. littoralis larvae. A few compounds (13-oxocardiopetamine (4), 9, and atisinium chloride (13)) had cytotoxic effects to insect-derived Sf9 cells with varying degrees of selectivity with respect to mammalian CHO cells. Compounds 4 and 15,22-O-diacetyl-19-oxodihydroatisine (10) increased Trypanosoma cruzi mortality. Our results support the plant protective role of C20 diterpenoid alkaloids and open a new field for parasite control strategies.

  4. Insects: A nutritional alternative

    NASA Technical Reports Server (NTRS)

    Dufour, P. A.

    1981-01-01

    Insects are considered as potential food sources in space. Types of insects consumed are discussed. Hazards of insect ingestion are considered. Insect reproduction, requirements, and raw materials conversion are discussed. Nutrition properties and composition of insects are considered. Preparation of insects as human food is discussed.

  5. Insect evolution.

    PubMed

    Engel, Michael S

    2015-10-01

    It goes without saying that insects epitomize diversity, and with over a million documented species they stand out as one of the most remarkable lineages in the 3.5-billion-year history of life on earth (Figure 1). This reality is passé to even the layperson and is taken for granted in the same way none of us think much of our breathing as we go about our day, and yet insects are just as vital to our existence. Insects are simultaneously familiar and foreign to us, and while a small fraction are beloved or reviled, most are simply ignored. These inexorable evolutionary overachievers outnumber us all, their segmented body plan is remarkably labile, they combine a capacity for high rates of speciation with low levels of natural extinction, and their history of successes eclipses those of the more familiar ages of dinosaurs and mammals alike. It is their evolution - persisting over vast expanses of geological time and inextricably implicated in the diversification of other lineages - that stands as one of the most expansive subjects in biology. PMID:26439349

  6. Insect evolution.

    PubMed

    Engel, Michael S

    2015-10-01

    It goes without saying that insects epitomize diversity, and with over a million documented species they stand out as one of the most remarkable lineages in the 3.5-billion-year history of life on earth (Figure 1). This reality is passé to even the layperson and is taken for granted in the same way none of us think much of our breathing as we go about our day, and yet insects are just as vital to our existence. Insects are simultaneously familiar and foreign to us, and while a small fraction are beloved or reviled, most are simply ignored. These inexorable evolutionary overachievers outnumber us all, their segmented body plan is remarkably labile, they combine a capacity for high rates of speciation with low levels of natural extinction, and their history of successes eclipses those of the more familiar ages of dinosaurs and mammals alike. It is their evolution - persisting over vast expanses of geological time and inextricably implicated in the diversification of other lineages - that stands as one of the most expansive subjects in biology.

  7. Insect abatement system

    NASA Technical Reports Server (NTRS)

    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.

  8. Allergies to Insect Venom

    MedlinePlus

    ... The smell of food attracts these insects.  Use insect repellents and keep insecticide available. Treatment tips:  Venom immunotherapy (allergy shots to insect venom(s) is highly effective in preventing subsequent sting ...

  9. Insect transgenesis and the sterile insect technique

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The establishment of broadly applicable insect transgenesis systems will enable the analyses of gene function in diverse insect species. This will greatly increase our understanding of diverse aspects of biology so far not functionally addressable. Moreover, insect transgenesis will provide novel st...

  10. What Makes an Insect an Insect?

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides background information on characteristics common to all insects, activities, and student materials (ready-to-copy games, puzzles, coloring pages, worksheets, and/or mazes) which describe: how insects are classified; how they are different from other animals; and the main insect characteristics. Activities include recommended age levels,…

  11. Insect-ual Pursuits.

    ERIC Educational Resources Information Center

    Mallow, David

    1991-01-01

    Explains how insects can be used to stimulate student writing. Describes how students can create their own systems to classify and differentiate insects. Discusses insect morphology and includes three detailed diagrams. The author provides an extension activity where students hypothesize about the niche of an insect based on its anatomy. (PR)

  12. Book Review: Insect Virology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. [Assortative mating and maintenance of intrapopulation polymorphism in wild populations and laboratory cultures of insects].

    PubMed

    Benkovskaya, G V; Nikonorov, Yu M

    2015-01-01

    Speciation as a micro-evolutionary process begins with emerging of intraspecies differentiation, which is associated with establishment of reproductive isolation. One of intrinsic isolation factors ensuring physiological isolation is assortative mating. In course of long-term field observations in the Southern Urals (Republic of Bashkortostan) and prolonged laboratory experiments, we have detected assortative mating in populations of potato beetle Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae). Three morphotypes were singled out by the extent of integument melanization, namely achromists (A), melanists (M), and intermediate type (I), and frequency of occurrence of these morphotypes imago pairs significantly deviated from random distribution, thus manifesting the assortative mating. Under in copulo conditions, mating between achromist males (A) and melanist females (M) where active choice belonged to males was not registered. In.laboratory experiments, in the sample of 40 artificially formed pairs, there were detected significant differences in longevity and fecundity of different morphotype imagoes. Achromists and melanists had significantly (almost two times) higher longevity as compared with intermediate type. Females of intermediate type were significantly more fecund in homonomous crossings than achromists and melanists. It is shown that pairs offspring also differs significantly in viability, with highest viability being characteristic for offspring from females of A- and I-type. The differences revealed are indicative of different reproductive strategies that exist in populations. In laboratory line S of house fly Musca domestica L. (Diptera: Muscidae) the presence of individuals with different reproductive strategies related to longevity is detected. Maximum longevity in inbred lines Sh28 (short living) and L2 (long living), isolated from the line S, significantly differed almost twofold. In the line of short living flies, mass reproduction occurs

  14. Insects and Scorpions

    MedlinePlus

    ... gov . Workplace Safety and Health Topics Insects & Scorpions Bees, Wasps, and Hornets Fire Ants Scorpions Additional Resources ... to outdoor workers. Stinging or biting insects include bees, wasps, hornets, and fire ants. The health effects ...

  15. Insects: An Interdisciplinary Unit

    ERIC Educational Resources Information Center

    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.

  16. Ecophysiology and insect herbivory

    SciTech Connect

    Clancy, K.M.; Wagner, M.R.; Reich, P.B.

    1995-07-01

    The relationship of insect herbivory to conifer physiology is examined. Aspects of nutrient assimilation, nutrient distribution, water stress, and climatic change are correlated to defoliation by insects. Other factors examined include plant age, density, structure, soils, and plant genotype.

  17. Respiration in Aquatic Insects.

    ERIC Educational Resources Information Center

    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)

  18. Insects and Spiders.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    This set of teaching aids consists of nine Audubon Nature Bulletins, providing teachers and students with informational reading on insects and spiders. The bulletins have these titles: What Good Are Insects, How Insects Benefit Man, Life of the Honey Bee, Ants and Their Fascinating Ways, Mosquitoes and Other Flies, Caterpillars, Spiders and Silk,…

  19. Sunflower insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Like other annual crops, sunflowers are fed upon by a variety of insect pests capable of reducing yields. Though there are a few insects which are considered consistent or severe (e.g., sunflower moth, banded sunflower moth, red sunflower seed weevil), many more insects are capable of causing proble...

  20. Exploring Sound with Insects

    ERIC Educational Resources Information Center

    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…

  1. Insects and Others.

    ERIC Educational Resources Information Center

    Mills, Richard

    1984-01-01

    Several ideas for observing insects and soil animals in the classroom are provided. Also provided are: (1) procedures for making insect cages with milk cartons; (2) suggestions for collecting and feeding insects; and (3) techniques for collecting and identifying soil animals. (BC)

  2. InsectBase: a resource for insect genomes and transcriptomes

    PubMed Central

    Yin, Chuanlin; Shen, Gengyu; Guo, Dianhao; Wang, Shuping; Ma, Xingzhou; Xiao, Huamei; Liu, Jinding; Zhang, Zan; Liu, Ying; Zhang, Yiqun; Yu, Kaixiang; Huang, Shuiqing; Li, Fei

    2016-01-01

    The genomes and transcriptomes of hundreds of insects have been sequenced. However, insect community lacks an integrated, up-to-date collection of insect gene data. Here, we introduce the first release of InsectBase, available online at http://www.insect-genome.com. The database encompasses 138 insect genomes, 116 insect transcriptomes, 61 insect gene sets, 36 gene families of 60 insects, 7544 miRNAs of 69 insects, 96 925 piRNAs of Drosophila melanogaster and Chilo suppressalis, 2439 lncRNA of Nilaparvata lugens, 22 536 pathways of 78 insects, 678 881 untranslated regions (UTR) of 84 insects and 160 905 coding sequences (CDS) of 70 insects. This release contains over 12 million sequences and provides search functionality, a BLAST server, GBrowse, insect pathway construction, a Facebook-like network for the insect community (iFacebook), and phylogenetic analysis of selected genes. PMID:26578584

  3. Synthesis and Antifeedant Activity of Racemic and Optically Active Hydroxy Lactones with the p-Menthane System.

    PubMed

    Grudniewska, Aleksandra; Kłobucki, Marek; Dancewicz, Katarzyna; Szczepanik, Maryla; Gabryś, Beata; Wawrzeńczyk, Czesław

    2015-01-01

    Two racemic and two enantiomeric pairs of new δ-hydroxy-γ-lactones based on the p-menthane system were prepared from racemic and optically active cis- and trans-piperitols. The Johnson-Claisen rearrangement of the piperitols, epoxidation of the γδ-unsaturated esters, and acidic lactonization of the epoxy esters were described. The structures of the compounds were confirmed spectroscopically. The antifeedant activities of the hydroxy lactones and racemic piperitone were evaluated against three insect pests: lesser mealworm, Alphitobius diaperinus (Panzer); Colorado potato beetle, Leptinotarsa decemlineata (Say); and peach-potato aphid, Myzus persicae (Sulz.). The chemical transformation of piperitone by the introduction of a lactone moiety and a hydroxy group changed its antifeedant properties. Behavioral bioassays showed that the feeding deterrent activity depended on the insect species and the structure of the compounds. All hydroxy lactones deterred the settling of M. persicae. Among chewing insects, the highest sensitivity showed A. diaperinus adults. PMID:26132506

  4. Synthesis and Antifeedant Activity of Racemic and Optically Active Hydroxy Lactones with the p-Menthane System

    PubMed Central

    Grudniewska, Aleksandra; Kłobucki, Marek; Dancewicz, Katarzyna; Szczepanik, Maryla; Gabryś, Beata; Wawrzeńczyk, Czesław

    2015-01-01

    Two racemic and two enantiomeric pairs of new δ-hydroxy-γ-lactones based on the p-menthane system were prepared from racemic and optically active cis- and trans-piperitols. The Johnson-Claisen rearrangement of the piperitols, epoxidation of the γδ-unsaturated esters, and acidic lactonization of the epoxy esters were described. The structures of the compounds were confirmed spectroscopically. The antifeedant activities of the hydroxy lactones and racemic piperitone were evaluated against three insect pests: lesser mealworm, Alphitobius diaperinus (Panzer); Colorado potato beetle, Leptinotarsa decemlineata (Say); and peach-potato aphid, Myzus persicae (Sulz.). The chemical transformation of piperitone by the introduction of a lactone moiety and a hydroxy group changed its antifeedant properties. Behavioral bioassays showed that the feeding deterrent activity depended on the insect species and the structure of the compounds. All hydroxy lactones deterred the settling of M. persicae. Among chewing insects, the highest sensitivity showed A. diaperinus adults. PMID:26132506

  5. Cellulolytic systems in insects.

    PubMed

    Watanabe, Hirofumi; Tokuda, Gaku

    2010-01-01

    Despite the presence of many carbohydrolytic activities in insects, their cellulolytic mechanisms are poorly understood. Whereas cellulase genes are absent from the genomes of Drosophila melanogaster or Bombyx mori, other insects such as termites produce their own cellulases. Recent studies using molecular biological techniques have brought new insights into the mechanisms by which the insects and their microbial symbionts digest cellulose in the small intestine. DNA sequences of cellulase and associated genes, as well as physiological and morphological information about the digestive systems of cellulase-producing insects, may allow the efficient use of cellulosic biomass as a sustainable energy source.

  6. Insect bites and stings

    MedlinePlus

    ... 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.

  7. Insects and Bugs

    ERIC Educational Resources Information Center

    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.…

  8. Corazonin in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corazonin is a peptidergic neurohormone of insects which is expressed in neurosecretory neurons of the pars lateralis of the protocerebrum and transported via nervi corpus cardiaci in the storage lobes of the corpora cardiaca. This peptide occurs with a single isofomr in all insects studied so far,...

  9. Sterile Insect Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter discusses the history of the development of quality control tchnology, the principles and philosophy of assessing insect quality, and the relative importance of the various parameters used to assess insect quality in the context of mass-rearing for the SIT. Quality control is most devel...

  10. Sugarcane insect update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect are an important group of pests affecting sugarcane production. Agricultural consultants play an important role is assisting sugarcane farmers to choose the most appropriated means of managing damaging infestations of insects in their crop. In this presentation, information will be presented ...

  11. Insects: Bugged Out!

    ERIC Educational Resources Information Center

    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…

  12. Principal Areas of Insect Research

    ERIC Educational Resources Information Center

    Williams, Carroll M.

    1973-01-01

    Research for insect control has been quite complex. However, recent knowledge of using insect hormones against them has opened new vistas for producing insecticides which may be harmless to human population. Current areas of insect research are outlined. (PS)

  13. Extraordinary Adaptive Plasticity of Colorado Potato Beetle: "Ten-Striped Spearman" in the Era of Biotechnological Warfare.

    PubMed

    Cingel, Aleksandar; Savić, Jelena; Lazarević, Jelica; Ćosić, Tatjana; Raspor, Martin; Smigocki, Ann; Ninković, Slavica

    2016-09-13

    Expanding from remote areas of Mexico to a worldwide scale, the ten-striped insect, the Colorado potato beetle (CPB, Leptinotarsa decemlineata Say), has risen from being an innocuous beetle to a prominent global pest. A diverse life cycle, phenotypic plasticity, adaptation to adverse conditions, and capability to detoxify or tolerate toxins make this insect appear to be virtually "indestructible". With increasing advances in molecular biology, tools of biotechnological warfare were deployed to combat CPB. In the last three decades, genetically modified potato has created a new challenge for the beetle. After reviewing hundreds of scientific papers dealing with CPB control, it became clear that even biotechnological means of control, if used alone, would not defeat the Colorado potato beetle. This control measure once again appears to be provoking the potato beetle to exhibit its remarkable adaptability. Nonetheless, the potential for adaptation to these techniques has increased our knowledge of this pest and thus opened possibilities for devising more sustainable CPB management programs.

  14. Laboratory Evaluation of Isaria fumosorosea CCM 8367 and Steinernema feltiae Ustinov against Immature Stages of the Colorado Potato Beetle.

    PubMed

    Hussein, Hany M; Skoková Habuštová, Oxana; Půža, Vladimír; Zemek, Rostislav

    2016-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata, has developed resistance to most registered pesticides and has become one of the most difficult insect pests to control. Development of new biopesticides targeting this pest might solve the resistance problem and contribute to sustainable crop production. Laboratory experiments were conducted to assess the efficacy of Isaria fumosorosea (syn. Paecilomyces fumosoroseus) strain CCM 8367 against L. decemlineata when applied alone or combined with the entomopathogenic nematode Steinernema feltiae. The last-instar larvae of the Colorado potato beetle showed the highest susceptibility to I. fumosorosea followed by pre-pupae and pupae. The median lethal concentration (LC50) was estimated to be 1.03×106 blastospores/ml. The strain CCM 8367 was more virulent, causing 92.6% mortality of larvae (LT50 = 5.0 days) compared to the reference strain Apopka 97, which caused 54.5% mortality (LT50 = 7.0 days). The combined application of the fungus with the nematodes increased the mortality up to 98.0%. The best results were obtained when S. feltiae was applied simultaneously with I. fumosorosea (LT50 = 2.0 days); later application negatively affected both the penetration rate and the development of the nematodes. We can conclude that the strain CCM 8367 of I. fumosorosea is a prospective biocontrol agent against immature stages of L. decemlineata. For higher efficacy, application together with an entomopathogenic nematode is recommended. PMID:27015633

  15. Laboratory Evaluation of Isaria fumosorosea CCM 8367 and Steinernema feltiae Ustinov against Immature Stages of the Colorado Potato Beetle

    PubMed Central

    Hussein, Hany M.; Skoková Habuštová, Oxana; Půža, Vladimír; Zemek, Rostislav

    2016-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata, has developed resistance to most registered pesticides and has become one of the most difficult insect pests to control. Development of new biopesticides targeting this pest might solve the resistance problem and contribute to sustainable crop production. Laboratory experiments were conducted to assess the efficacy of Isaria fumosorosea (syn. Paecilomyces fumosoroseus) strain CCM 8367 against L. decemlineata when applied alone or combined with the entomopathogenic nematode Steinernema feltiae. The last-instar larvae of the Colorado potato beetle showed the highest susceptibility to I. fumosorosea followed by pre-pupae and pupae. The median lethal concentration (LC50) was estimated to be 1.03×106 blastospores/ml. The strain CCM 8367 was more virulent, causing 92.6% mortality of larvae (LT50 = 5.0 days) compared to the reference strain Apopka 97, which caused 54.5% mortality (LT50 = 7.0 days). The combined application of the fungus with the nematodes increased the mortality up to 98.0%. The best results were obtained when S. feltiae was applied simultaneously with I. fumosorosea (LT50 = 2.0 days); later application negatively affected both the penetration rate and the development of the nematodes. We can conclude that the strain CCM 8367 of I. fumosorosea is a prospective biocontrol agent against immature stages of L. decemlineata. For higher efficacy, application together with an entomopathogenic nematode is recommended. PMID:27015633

  16. Laboratory Evaluation of Isaria fumosorosea CCM 8367 and Steinernema feltiae Ustinov against Immature Stages of the Colorado Potato Beetle.

    PubMed

    Hussein, Hany M; Skoková Habuštová, Oxana; Půža, Vladimír; Zemek, Rostislav

    2016-01-01

    The Colorado potato beetle, Leptinotarsa decemlineata, has developed resistance to most registered pesticides and has become one of the most difficult insect pests to control. Development of new biopesticides targeting this pest might solve the resistance problem and contribute to sustainable crop production. Laboratory experiments were conducted to assess the efficacy of Isaria fumosorosea (syn. Paecilomyces fumosoroseus) strain CCM 8367 against L. decemlineata when applied alone or combined with the entomopathogenic nematode Steinernema feltiae. The last-instar larvae of the Colorado potato beetle showed the highest susceptibility to I. fumosorosea followed by pre-pupae and pupae. The median lethal concentration (LC50) was estimated to be 1.03×106 blastospores/ml. The strain CCM 8367 was more virulent, causing 92.6% mortality of larvae (LT50 = 5.0 days) compared to the reference strain Apopka 97, which caused 54.5% mortality (LT50 = 7.0 days). The combined application of the fungus with the nematodes increased the mortality up to 98.0%. The best results were obtained when S. feltiae was applied simultaneously with I. fumosorosea (LT50 = 2.0 days); later application negatively affected both the penetration rate and the development of the nematodes. We can conclude that the strain CCM 8367 of I. fumosorosea is a prospective biocontrol agent against immature stages of L. decemlineata. For higher efficacy, application together with an entomopathogenic nematode is recommended.

  17. Feeding the insect industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article reports the use of insect colloidal artificial diets suitable for the rearing of economically important arthropods, such as Lygus lineolaris, Lygus hesperus, Coleomegilla maculata, and Phytoseiulus persimilis The different diets contain key nutrients such as proteins, carbohydrates, vit...

  18. Insect Bites and Stings

    MedlinePlus

    ... they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and ... have severe allergic reactions to insect bites and stings (such as anaphylaxis), carry an emergency epinephrine kit

  19. Insects and climate change

    SciTech Connect

    Elias, S.A. )

    1991-09-01

    In this article the author describes some of the significant late glacial and Holocene changes that occurred in the Rocky Mountains, including the regional extirpation of certain beetle species. The fossil data presented here summarize what is known about regional insect responses to climate change in terms of species stability and geographic distribution. To minimize potential problems of species interactions (i.e., insect-host plant relationships, host-parasite relationships, and other interactions that tie a particular insect species' distribution to that of another organism), only predators and scavengers are discussed. These insects respond most rapidly to environmental changes, because for the most part they are not tied to any particular type of vegetation.

  20. Insect hemolymph clotting.

    PubMed

    Dushay, Mitchell S

    2009-08-01

    The clot's appearance in different large-bodied insects has been described, but until recently, little was known about any insect clot's molecular makeup, and few experiments could directly test its function. Techniques have been developed in Drosophila (fruit fly) larvae to identify clotting factors that can then be tested for effects on hemostasis, healing, and immunity. This has revealed unanticipated complexity in the hemostatic mechanisms in these larvae. While the clot's molecular structure is not yet fully understood, progress is being made, and the loss of clotting factors has been shown to cause subtle immune defects. The few similarities between coagulation in different insect species and life stages, and the current state of knowledge about coagulation in insects are discussed. PMID:19418022

  1. Evolution of the Insects

    NASA Astrophysics Data System (ADS)

    Grimaldi, David; Engel, Michael S.

    2005-05-01

    This book chronicles the complete evolutionary history of insects--their living diversity and relationships as well as 400 million years of fossils. Introductory sections cover the living species diversity of insects, methods of reconstructing evolutionary relationships, basic insect structure, and the diverse modes of insect fossilization and major fossil deposits. Major sections then explore the relationships and evolution of each order of hexapods. The volume also chronicles major episodes in the evolutionary history of insects from their modest beginnings in the Devonian and the origin of wings hundreds of millions of years before pterosaurs and birds to the impact of mass extinctions and the explosive radiation of angiosperms on insects, and how they evolved into the most complex societies in nature. Whereas other volumes focus on either living species or fossils, this is the first comprehensive synthesis of all aspects of insect evolution. Illustrated with 955 photo- and electron- micrographs, drawings, diagrams, and field photos, many in full color and virtually all of them original, this reference will appeal to anyone engaged with insect diversity--professional entomologists and students, insect and fossil collectors, and naturalists. David Grimaldi and Michael S. Engel have collectively published over 200 scientific articles and monographs on the relationships and fossil record of insects, including 10 articles in the journals Science, Nature, and Proceedings of the National Academy of Sciences. David Grimaldi is curator in the Division of Invertebrate Zoology, American Museum of Natural History and adjunct professor at Cornell University, Columbia University, and the City University of New York. David Grimaldi has traveled in 40 countries on 6 continents, collecting and studying recent species of insects and conducting fossil excavations. He is the author of Amber: Window to the Past (Abrams, 2003). Michael S. Engel is an assistant professor in the

  2. Exploring Insect Vision

    ERIC Educational Resources Information Center

    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,…

  3. Important Insect Pests of Fruit - Important Insect Pests of Nuts - Field Crop Insect Pests - Insect Pests of Vegetable Crops.

    ERIC Educational Resources Information Center

    Gesell, Stanley G.; And Others

    This document consists of four agriculture extension service publications from Pennsylvania State University. The titles are: (1) Important Insect Pests of Fruit; (2) Important Insect Pests of Nuts; (3) Field Crop Insect Pests; and (4) Insect Pests of Vegetable Crops. The first publication gives the hosts, injury, and description of 22 insect…

  4. Insect--plant adaptations.

    PubMed

    Southwood, T R

    1984-01-01

    The adaptation of insects to plants probably commenced in the early Permian period, though most current associations will be more recent. A major burst of adaptation must have followed the rise of the Angiosperms in the Cretaceous period, though some particular associations are as recent as this century. Living plants form a large proportion of the potential food in most habitats, though insects have had to overcome certain general hurdles to live and feed on them. Insects affect the reproduction and survival of plants, and thus the diversity of plant secondary chemicals may have evolved as a response. Where an insect species has a significant effect on a plant species that is its only host, coevolution may be envisaged. A spectacular example is provided by Heliconius butterflies and passion flower vines, studied by L.E. Gilbert and others. But such cases may be likened to 'vortices in the evolutionary stream': most plant species are influenced by a range of phytophagous insects so that selection will be for general defences--a situation termed diffuse coevolution. Evidence is presented on recent host-plant shifts to illustrate both the restrictions and the flexibility in current insect-plant associations.

  5. Transformation systems in insects.

    PubMed

    O'Brochta, David A; Atkinson, Peter W

    2004-01-01

    Genetic transformation is an important technology that provides unique opportunities to find, isolate, and analyze genes, as well as to create organisms with unique functional characteristics. Insect biologists have been developing genetic transformation technologies that rely extensively on transposable elements. A number of class II transposable elements isolated originally from insects have been converted into broad host range insect gene vectors. Class II transposable elements are particularly amenable to gene vector development, although they suffer from some limitations such as low rates of recombination. Use of these gene vectors requires the physical introduction of the vectors into developing insect embryos by microinjection. Microinjection methods vary to accommodate the unique physical and developmental characteristics of the target insects. All methods rely on the use of fine glass needles in conjunction with micromanipulators and a microscope. A serious constraint on the use of existing systems can be the inefficiency of successfully delivering the gene vectors to the germ cells of the developing embryo. The general method for vector delivery to insect germ cells is described, as well as variations that are useful under some conditions.

  6. Insect--plant adaptations.

    PubMed

    Southwood, T R

    1984-01-01

    The adaptation of insects to plants probably commenced in the early Permian period, though most current associations will be more recent. A major burst of adaptation must have followed the rise of the Angiosperms in the Cretaceous period, though some particular associations are as recent as this century. Living plants form a large proportion of the potential food in most habitats, though insects have had to overcome certain general hurdles to live and feed on them. Insects affect the reproduction and survival of plants, and thus the diversity of plant secondary chemicals may have evolved as a response. Where an insect species has a significant effect on a plant species that is its only host, coevolution may be envisaged. A spectacular example is provided by Heliconius butterflies and passion flower vines, studied by L.E. Gilbert and others. But such cases may be likened to 'vortices in the evolutionary stream': most plant species are influenced by a range of phytophagous insects so that selection will be for general defences--a situation termed diffuse coevolution. Evidence is presented on recent host-plant shifts to illustrate both the restrictions and the flexibility in current insect-plant associations. PMID:6559112

  7. Insect bite reactions.

    PubMed

    Singh, Sanjay; Mann, Baldeep Kaur

    2013-01-01

    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 serious adverse effects

  8. Enterococci in Insects

    PubMed Central

    Martin, Jonathan D.; Mundt, J. Orvin

    1972-01-01

    Enterococci were obtained from 213 of 403 insects cultured during a 14-month period, in numbers from 103 to 3 × 107/g of insect. Insects were taken only from nonurban, wild, and cultivated fields and woods. In species of insects carrying them, enterococci were not always present in every individual cultured, and often more than one species of enterococcus occurred within a species. Enterococci were obtained from certain insects taken in the field during the dormant season, suggesting their role as overwintering agents. They were generally present in species feeding on nectar, succulent plant parts, and on and ir forest litter, but not from insects feeding on less succulent leaves and stems. Streptococcus faecalis was recovered from 32%, Streptococcus faecium from 22.4%, and Streptococcus faecium var. casseliflavus from 43.5% of members of the 37 taxa of insects. S. faecalis and S. faecium var. casseliflavus exhibit a high percent of conformity to the properties published for them. The heterogeneity in properties of S. faecium is similar to that found for the species taken from plants. Many fail to grow in broth at 45 C or in broth containing 6.5% NaCl; 50% of the cultures ferment both melezitose and melibiose, and a few ferment neither sugar. The remainder ferment melibiose only. Failure to reduce methylene blue in milk by S. faecalis and S. faecium is correlated with the inability to ferment lactose. More than 93% of the cultures of S. faecalis digest casein in milk from the top downward, following the production of a soft, flowing curd. Because this property is not characteristic of S. faecalis taken from humans, the reaction in litmus milk is suggested as a means of differentiation between cultures of remote and innocent origin in nature and recent, human pollution. PMID:4628796

  9. Insect bite reactions.

    PubMed

    Singh, Sanjay; Mann, Baldeep Kaur

    2013-01-01

    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 serious adverse effects

  10. Migration strategies of insects.

    PubMed

    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

  11. Behavioral Immunity in Insects

    PubMed Central

    de Roode, Jacobus C.; Lefèvre, Thierry

    2012-01-01

    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. PMID:26466629

  12. Cognition in insects

    PubMed Central

    Webb, Barbara

    2012-01-01

    A traditional view of cognition is that it involves an internal process that represents, tracks or predicts an external process. This is not a general characteristic of all complex neural processing or feedback control, but rather implies specific forms of processing giving rise to specific behavioural capabilities. In this paper, I will review the evidence for such capabilities in insect navigation and learning. Do insects know where they are, or do they only know what to do? Do they learn what stimuli mean, or do they only learn how to behave? PMID:22927570

  13. Insect Repellents: Protect Your Child from Insect Bites

    MedlinePlus

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

  14. Structural diversity and defensive properties of norditerpenoid alkaloids.

    PubMed

    González-Coloma, Azucena; Reina, Matías; Medinaveitia, Alberto; Guadaño, Ana; Santana, Omar; Martínez-Díaz, Rafael; Ruiz-Mesía, Lastenia; Alva, Allenger; Grandez, Maritza; Díaz, Rafael; Gavín, José A; De la Fuente, Gabriel

    2004-07-01

    We have tested the insect antifeedant and toxic activity of 43 norditerpenoid alkaloids on Spodoptera littoralis and Leptinotarsa decemlineata including eserine (physostigmine), anabasine, and atropine. Antifeedant effects of the test compounds were structure- and species-dependent. The most active antifeedants to L. decemlineata were 1,14-diacetylcardiopetaline (9) and 18-hydroxy- 14-O-methylgadesine (33), followed by 8-O-methylconsolarine (12), 14-O-acetyldelectinine (27), karakoline (7), cardiopetaline (8), 18-O-demethylpubescenine (13), 14-O-acetyldeltatsine (18), takaosamine (21), ajadine (24), and 8-O-methylcolumbianine (6) (EC50 < 1 microg/cm2). This insect showed a moderate response to atropine. S. littoralis had the strongest antifeedant response to 24, 18, 14-O-acetyldelcosine (19), and delphatine (29) (EC50 < 3 microg/cm2). None of the model substances affected the feeding behavior of this insect. The most toxic compound to L. decemlineata was aconitine (1), followed by cardiopetalidine (10) (% mortality > 60), 14-deacetylpubescenine (14), 18-O-benzoyl-18-O-demethyl-14-O-deacetylpubescenine (17), 14-O-acetyldelcosine (19), 14-deacetylajadine (25) and methyllycaconitine (30) (% mortality > 45). Orally injected S. littoralis larvae were negatively affected by 1, cardiopetaline (8), 10, 1,14-O-acetylcardiopetalidina (11), 12, 14, 1,18-O-diacetyl-19-oxo-gigactonine (41), olivimine (43), and eserine in varying degrees. Their antifeedant or insecticidal potencies did not parallel their reported nAChR binding activity, but did correlate with the agonist/antagonist insecticidal/antifeedant model proposed for nicotininc insecticides. A few compounds [14, tuguaconitine (38), 14-demethyldelboxine (40), 19, dehydrodelsoline (36), 18-O-demethylpubescenine (13), 41, 9, and delcosine (23)] had selective cytotoxic effects to ward insect-derived Sf9 cells. None were cytotoxic to mammalian CHO cells and none increased Trypanosoma cruzi mortality. The selective cytotoxic

  15. Protecting Yourself from Stinging Insects

    MedlinePlus

    ... at risk of being stung by flying insects (bees, wasps, and hornets) and fire ants. While most ... by several stinging insects, run to get away. (Bees release a chemical when they sting, which attracts ...

  16. Dispersal of forest insects

    NASA Technical Reports Server (NTRS)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  17. Investigation--Insects!

    ERIC Educational Resources Information Center

    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)

  18. Irradiating insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a non-technical article focusing on phytosanitary uses of irradiation. In a series of interview questions, I present information on the scope of the invasive species problem and the contribution of international trade in agricultural products to the movement of invasive insects. This is foll...

  19. Insect mass production technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects provide a very promising alternative for the future production of animal protein. Their nutritional value in conjunction with their food conversion efficiency and low water requirements, make them a more sustainable choice for the production of food and animal origin. However, to realize the...

  20. Olfactory signaling in insects.

    PubMed

    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.

  1. Corn insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historically, the major corn insect pests in South Dakota have been the larvae of corn rootworms (northern and western), European corn borer, and black cutworm. Bt-corn hybrids are effective against most of these pests. However, there are also minor or sporadic pests of corn in South Dakota includin...

  2. Insects. Thematic Unit.

    ERIC Educational Resources Information Center

    Gosnell, Kathee

    This book is a captivating whole-language thematic unit about the study of insects, relating it to our understanding of the past and our hopes for using our knowledge in the present to balance the ecosystem in the future. It contains a wide variety of lesson ideas and reproducible pages designed for use with intermediate students. At its core,…

  3. Colour constancy in insects.

    PubMed

    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.

  4. Recycled Insect Models

    ERIC Educational Resources Information Center

    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…

  5. Fluorescence in insects

    NASA Astrophysics Data System (ADS)

    Welch, Victoria L.; Van Hooijdonk, Eloise; Intrater, Nurit; Vigneron, Jean-Pol

    2012-10-01

    Fluorescent molecules are much in demand for biosensors, solar cells, LEDs and VCSEL diodes, therefore, considerable efforts have been expended in designing and tailoring fluorescence to specific technical applications. However, naturally occurring fluorescence of diverse types has been reported from a wide array of living organisms: most famously, the jellyfish Aequorea victoria, but also in over 100 species of coral and in the cuticle of scorpions, where it is the rule, rather than the exception. Despite the plethora of known insect species, comparatively few quantitative studies have been made of insect fluorescence. Because of the potential applications of natural fluorescence, studies in this field have relevance to both physics and biology. Therefore, in this paper, we review the literature on insect fluorescence, before documenting its occurrence in the longhorn beetles Sternotomis virescens, Sternotomis variabilis var. semi rufescens, Anoplophora elegans and Stellognatha maculata, the tiger beetles Cicindela maritima and Cicindela germanica and the weevil Pachyrrhynchus gemmatus purpureus. Optical features of insect fluorescence, including emitted wavelength, molecular ageing and naturally occurring combinations of fluorescence with bioluminescence and colour-producing structures are discussed.

  6. Radar cross section of insects

    NASA Astrophysics Data System (ADS)

    Riley, J. R.

    1985-02-01

    X-band measurements of radar cross section as a function of the angle between insect body axis and the plane of polarization are presented. A finding of particular interest is that in larger insects, maximum cross section occurs when the E-vector is perpendicular to the body axis. A new range of measurements on small insects (aphids, and planthoppers) is also described, and a comprehensive summary of insect cross-section data at X-band is given.

  7. Insect endosymbionts: manipulators of insect herbivore trophic interactions?

    PubMed

    Clark, Emily L; Karley, Alison J; Hubbard, Stephen F

    2010-08-01

    Throughout their evolutionary history, insects have formed multiple relationships with bacteria. Although many of these bacteria are pathogenic, with deleterious effects on the fitness of infected insects, there are also numerous examples of symbiotic bacteria that are harmless or even beneficial to their insect host. Symbiotic bacteria that form obligate or facultative associations with insects and that are located intracellularly in the host insect are known as endosymbionts. Endosymbiosis can be a strong driving force for evolution when the acquisition and maintenance of a microorganism by the insect host results in the formation of novel structures or changes in physiology and metabolism. The complex evolutionary dynamics of vertically transmitted symbiotic bacteria have led to distinctive symbiont genome characteristics that have profound effects on the phenotype of the host insect. Symbiotic bacteria are key players in insect-plant interactions influencing many aspects of insect ecology and playing a key role in shaping the diversification of many insect groups. In this review, we discuss the role of endosymbionts in manipulating insect herbivore trophic interactions focussing on their impact on plant utilisation patterns and parasitoid biology.

  8. Meniscus-climbing insects

    NASA Astrophysics Data System (ADS)

    Hu, David L.; Kreider, Tim; Bush, John W. M.; Mit Department Of Mathematics Team

    2003-11-01

    Many millimetric water-walking insects are unable to climb the meniscii that border land and emerging vegetation using their traditional means of propulsion. We explore the novel means by which some insects succeed in so doing through a combined experimental and theoretical investigation. The grub Collembola ascends by distorting the free surface in order to generate a net horizontal surface tension force. The water treader Mesovelia climbs the meniscus by exploiting the Coulomb-like attraction between like-signed menisci: by lifting the free surface with its front and rear pairs of feet, it generates a tangential force that draws it up the slope. We examine the required force and torque balances on the body in order to calculate optimal leg configurations for meniscus climbers that are consistent with those observed.

  9. On quantifying insect movements

    SciTech Connect

    Wiens, J.A.; Crist, T.O. ); Milne, B.T. )

    1993-08-01

    We elaborate on methods described by Turchin, Odendaal Rausher for quantifying insect movement pathways. We note the need to scale measurement resolution to the study insects and the questions being asked, and we discuss the use of surveying instrumentation for recording sequential positions of individuals on pathways. We itemize several measures that may be used to characterize movement pathways and illustrate these by comparisons among several Eleodes beetles occurring in shortgrass steppe. The fractal dimension of pathways may provide insights not available from absolute measures of pathway configuration. Finally, we describe a renormalization procedure that may be used to remove sequential interdependence among locations of moving individuals while preserving the basic attributes of the pathway.

  10. Insect maintenance and transmission.

    PubMed

    Kingdom, Heather

    2013-01-01

    Phytoplasmas are plant pathogens of huge economic importance due to responsibility for crop yield losses worldwide. Institutions around the world are trying to understand and control this yield loss at a time when food security is high on government agendas. In order to fully understand the mechanisms of phytoplasma infection and spread, more insect vector and phytoplasma colonies will need to be established for research worldwide. Rearing and study of these colonies is essential in the research and development of phytoplasma control measures. This chapter highlights general materials and methods for raising insect vector colonies and maintenance of phytoplasmas. Specific methods of rearing the maize leafhopper and maize bushy stunt phytoplasma and the aster leafhopper and aster yellows phytoplasma strain witches' broom are also included. PMID:22987405

  11. Positive selection of digestive Cys proteases in herbivorous Coleoptera.

    PubMed

    Vorster, Juan; Rasoolizadeh, Asieh; Goulet, Marie-Claire; Cloutier, Conrad; Sainsbury, Frank; Michaud, Dominique

    2015-10-01

    Positive selection is thought to contribute to the functional diversification of insect-inducible protease inhibitors in plants in response to selective pressures exerted by the digestive proteases of their herbivorous enemies. Here we assessed whether a reciprocal evolutionary process takes place on the insect side, and whether ingestion of a positively selected plant inhibitor may translate into a measurable rebalancing of midgut proteases in vivo. Midgut Cys proteases of herbivorous Coleoptera, including the major pest Colorado potato beetle (Leptinotarsa decemlineata), were first compared using a codon-based evolutionary model to look for the occurrence of hypervariable, positively selected amino acid sites among the tested sequences. Hypervariable sites were found, distributed within -or close to- amino acid regions interacting with Cys-type inhibitors of the plant cystatin protein family. A close examination of L. decemlineata sequences indicated a link between their assignment to protease functional families and amino acid identity at positively selected sites. A function-diversifying role for positive selection was further suggested empirically by in vitro protease assays and a shotgun proteomic analysis of L. decemlineata Cys proteases showing a differential rebalancing of protease functional family complements in larvae fed single variants of a model cystatin mutated at positively selected amino acid sites. These data confirm overall the occurrence of hypervariable, positively selected amino acid sites in herbivorous Coleoptera digestive Cys proteases. They also support the idea of an adaptive role for positive selection, useful to generate functionally diverse proteases in insect herbivores ingesting functionally diverse, rapidly evolving dietary cystatins. PMID:26264818

  12. Fatigue of insect cuticle.

    PubMed

    Dirks, Jan-Henning; Parle, Eoin; Taylor, David

    2013-05-15

    Many parts of the insect exoskeleton experience repeated cyclic loading. Although the cuticle of insects and other arthropods is the second most common natural composite material in the world, so far nothing is known about its fatigue properties, despite the fact that fatigue undoubtedly limits the durability of body parts in vivo. For the first time, we here present experimental fatigue data of insect cuticle. Using force-controlled cyclic loading, we determined the number of cycles to failure for hind legs (tibiae) and hind wings of the locust Schistocerca gregaria, as a function of the applied cyclic stress. Our results show that, although both are made from cuticle, these two body parts behave very differently. Wing samples showed a large fatigue range, failing after 100,000 cycles when we applied 46% of the stress needed for instantaneous failure [the ultimate tensile strength (UTS)]. Legs, in contrast, were able to sustain a stress of 76% of the UTS for the same number of cycles to failure. This can be explained by the difference in the composition and structure of the material, two factors that, amongst others, also affect the well-known behaviour of engineering composites. Final failure of the tibiae occurred via one of two different failure modes--propagation in tension or buckling in compression--indicating that the tibia is 'optimized' by evolution to resist both failure modes equally. These results are further discussed in relation to the evolution and normal use of these two body parts.

  13. Edible insects are the future?

    PubMed

    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.

  14. Edible insects are the future?

    PubMed

    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. PMID:26908196

  15. Anaphylaxis to insect stings.

    PubMed

    Golden, David B K

    2015-05-01

    Anaphylaxis to insect stings has occurred in 3% of adults and can be fatal even on the first reaction. Large local reactions are more frequent but rarely dangerous. The chance of a systemic reaction to a sting is 5% to 10% in large local reactors and in children with mild (cutaneous) systemic reactions, and varies between 30% and 65% in adults with previous systemic reactions, depending on the severity of previous sting reactions. Baseline serum tryptase level is increased in many patients with sting anaphylaxis. Venom immunotherapy is 75% to 98% effective in preventing sting anaphylaxis.

  16. Aircraft anti-insect system

    NASA Technical Reports Server (NTRS)

    Spiro, Clifford Lawrence (Inventor); Fric, Thomas Frank (Inventor); Leon, Ross Michael (Inventor)

    1997-01-01

    Insect debris is removed from or prevented from adhering to insect impingement areas of an aircraft, particularly on an inlet cowl of an engine, by heating the area to 180.degree.-500.degree. C. An apparatus comprising a means to bring hot air from the aircraft engine to a plenum contiguous to the insect impingement area provides for the heating of the insect impingement areas to the required temperatures. The plenum can include at least one tube with a plurality of holes contained in a cavity within the inlet cowl. It can also include an envelope with a plurality of holes on its surface contained in a cavity within the inlet cowl.

  17. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  18. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture....2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of insect feeding. Metric Conversion Table...

  19. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture....2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of insect feeding. Metric Conversion Table...

  20. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  1. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence of insect feeding....

  2. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence of insect feeding....

  3. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  4. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence of insect feeding....

  5. 1977 Kansas Field Crop Insect Control Recommendations.

    ERIC Educational Resources Information Center

    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…

  6. Hydrodynamics of insect spermatozoa

    NASA Astrophysics Data System (ADS)

    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.

  7. Environmental RNAi in herbivorous insects.

    PubMed

    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. PMID:25802407

  8. Environmental RNAi in herbivorous insects

    PubMed Central

    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.

    2015-01-01

    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. PMID:25802407

  9. Environmental RNAi in herbivorous insects.

    PubMed

    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.

  10. Eicosanoids mediate insect hemocyte migration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  11. Plant Defense against Insect Herbivores

    PubMed Central

    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

  12. Chapter 21: Microsporidia in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The science of microsporidiology encompasses a diverse assemblage of pathogens from a large and varied group of hosts. Microsporidia, pathogenic protists related to the Fungi, are considered to be primary pathogens of many aquatic and terrestrial insect species and have important roles in insect po...

  13. Polarization Imaging and Insect Vision

    ERIC Educational Resources Information Center

    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.…

  14. Mosquitoes feeding on insect larvae.

    PubMed

    Harris, P; Riordan, D F; Cooke, D

    1969-04-11

    Caged Aedes aegypti and Culex tarsalis are attracted to insect larvae, engorge on their body fluids, and produce viable eggs. Attractiveness of the larvae is related to their size, shape, and color but not to their movement. The possibility that wild mosquitoes substitute insect hemolymph for vertebrate blood is discussed. PMID:5774191

  15. Reader Survey for INSECT ALERTS.

    ERIC Educational Resources Information Center

    Miller, Mason E.; Sauer, Richard J.

    To determine what might be done to improve "Insect Alerts," which is a newsletter that carries "information on insect biology, abundance, activity and interpretation of control need," put out through the Michigan Cooperative Extension Service 26 weeks a year, a survey was conducted. A mail questionnaire was sent to all 120 county extension…

  16. Population fluctuation in phytophagous insects

    SciTech Connect

    Redfearn, A.; Pimm, S.L. )

    1994-06-01

    We examined how community interactions affect year-to-year population variability in three groups of phytophagous insects: British aphids and moths, and Canadian moths. We first examined how the number of host plant species on which a given phytophagous insect species feeds affects its population variability. Specialist insect species showed a weak tendency to be more variable than generalist species. We then examined how the number of species of parasitoids from which a given phytophagous insects species suffers affects its population variability. Species that are host to few parasitoid species showed a weak tendency to be more variable than species with many parsitoid species. These relationships also depend on other aspects of the life histories of the phytophagous insect species.

  17. Insect Immunity to Entomopathogenic Fungi.

    PubMed

    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.

  18. The aerodynamics of insect flight.

    PubMed

    Sane, Sanjay P

    2003-12-01

    The flight of insects has fascinated physicists and biologists for more than a century. Yet, until recently, researchers were unable to rigorously quantify the complex wing motions of flapping insects or measure the forces and flows around their wings. However, recent developments in high-speed videography and tools for computational and mechanical modeling have allowed researchers to make rapid progress in advancing our understanding of insect flight. These mechanical and computational fluid dynamic models, combined with modern flow visualization techniques, have revealed that the fluid dynamic phenomena underlying flapping flight are different from those of non-flapping, 2-D wings on which most previous models were based. In particular, even at high angles of attack, a prominent leading edge vortex remains stably attached on the insect wing and does not shed into an unsteady wake, as would be expected from non-flapping 2-D wings. Its presence greatly enhances the forces generated by the wing, thus enabling insects to hover or maneuver. In addition, flight forces are further enhanced by other mechanisms acting during changes in angle of attack, especially at stroke reversal, the mutual interaction of the two wings at dorsal stroke reversal or wing-wake interactions following stroke reversal. This progress has enabled the development of simple analytical and empirical models that allow us to calculate the instantaneous forces on flapping insect wings more accurately than was previously possible. It also promises to foster new and exciting multi-disciplinary collaborations between physicists who seek to explain the phenomenology, biologists who seek to understand its relevance to insect physiology and evolution, and engineers who are inspired to build micro-robotic insects using these principles. This review covers the basic physical principles underlying flapping flight in insects, results of recent experiments concerning the aerodynamics of insect flight, as well

  19. Peripheral olfactory signaling in insects

    PubMed Central

    Suh, Eunho; Bohbot, Jonathan; Zwiebel, Laurence J.

    2014-01-01

    Olfactory signaling is a crucial component in the life history of insects. The development of precise and parallel mechanisms to analyze the tremendous amount of chemical information from the environment and other sources has been essential to their evolutionary success. Considerable progress has been made in the study of insect olfaction fueled by bioinformatics- based utilization of genomics along with rapid advances in functional analyses. Here we review recent progress in our rapidly emerging understanding of insect peripheral sensory reception and signal transduction. These studies reveal that the nearly unlimited chemical space insects encounter is covered by distinct chemosensory receptor repertoires that are generally derived by species-specific, rapid gene gain and loss, reflecting the evolutionary consequences of adaptation to meet their specific biological needs. While diverse molecular mechanisms have been put forth, often in the context of controversial models, the characterization of the ubiquitous, highly conserved and insect-specific Orco odorant receptor co-receptor has opened the door to the design and development of novel insect control methods to target agricultural pests, disease vectors and even nuisance insects. PMID:25584200

  20. Multi-predator effects produced by functionally distinct species vary with prey density.

    PubMed

    Werling, Ben P; Lowenstein, David M; Straub, Cory S; Gratton, Claudio

    2012-01-01

    Determining when multiple predator species provide better pest suppression than single species is a key step towards developing ecologically-informed biological control strategies. Theory and experiments predict that resource partitioning among functionally different predator species can strengthen prey suppression, because as a group they can access more prey types than functionally redundant predators. However, this prediction assumes that competition limits predation by functionally similar predators. Differences in prey density can alter the strength of competition, suggesting that prey abundance may modulate the effect of combining functionally diverse species. The experiment documented here examined the potential for functional differences among predator species to promote suppression of an insect pest, the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), at different prey densities. Predation was compared at two prey densities between microcosms that contained one predator species or two functionally distinct species: the lady beetle, Coleomegilla maculata De Geer (Coleoptera: Coccinellidae) that kills early L. decemlineata instars, and the soldier bug, Podisus maculiventris Say (Hemiptera: Pentatomidae) that kills late instars. The data show that combining these predators increased predation only when prey densities were low. This suggests that multiple predator species may only provide greater biological control than single species in systems where prey is limiting. PMID:22958369

  1. Pristionchus uniformis, should I stay or should I go? Recent host range expansion in a European nematode.

    PubMed

    D'Anna, Isabella; Sommer, Ralf J

    2011-12-01

    Pristionchus pacificus has been developed as a model system in evolutionary developmental biology, evolutionary ecology, and population genetics. This species has a well-known ecological association with scarab beetles. Generally, Pristionchus nematodes have a necromenic association with their beetle hosts. Arrested dauer larvae invade the insect and wait for the host's death to resume development. Only one Pristionchus species is known to frequently associate with a non-scarab beetle. Pristionchus uniformis has been isolated from the chrysomelid Leptinotarsa decemlineata, also known as the Colorado potato beetle, in Europe and North America, but is also found on scarab beetles. This unusual pattern of association with two unrelated groups of beetles on two continents requires the involvement of geographical and host range expansion events. Here, we characterized a collection of 81 P. uniformis isolates from North America and Europe and from both scarab beetles and L. decemlineata. We used population genetic and phylogenetic analyses of the mitochondrial gene nd2 to reconstruct the genetic history of P. uniformis and its beetle association. Olfactory tests on beetles chemical extracts showed that P. uniformis has a unique chemoattractive profile toward its beetle hosts. Our results provide evidence for host range expansion through host-switching events in Europe where P. uniformis was originally associated with scarab beetles and the nematode's subsequent invasion of North America. PMID:22393515

  2. Regeneration in insects.

    PubMed

    Marsh, J L; Theisen, H

    1999-08-01

    @9cIntroduction@21T issues exhibit an impressive ability to respond to a myriad of insults by repairing and regenerating complex structures. The elegant and orderly process of regeneration provides clues to the mechanisms of pattern formation but also offers the hope that the process might one day be manipulated to replace damaged body parts. To manipulate the process, it will be necessary to understand the genetic basis of the process. In the case of the insect leg, we are coming close to such a level of understanding and many of the lessons learned are relevant to vertebrate systems. A dynamic web of gene regulatory networks appears to create a robust self-organizing system that is at once extremely intricate but also perhaps simple in its reliance on a few key signaling pathways and a few simple processes, e.g. autoactivation and lateral inhibition. Here we will summarize what has been learned about the networks of gene regulation present in the Drosophila leg discs and then we will explore how the regenerative responses to different insults can be understood as predictable responses to these networks. Each of the regulatory networks could themselves serve as the subject of a detailed review and that is beyond the scope of this discussion. Here we will focus on the interplay between the regulatory networks in patterning the tissue.

  3. Insect symbionts in food webs

    PubMed Central

    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

  4. Insect symbionts in food webs.

    PubMed

    McLean, Ailsa H C; Parker, Benjamin J; Hrček, Jan; Henry, Lee M; Godfray, H Charles J

    2016-09-01

    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'.

  5. Freshwater Biodiversity and Insect Diversification

    PubMed Central

    Dijkstra, Klaas-Douwe B.; Monaghan, Michael T.; Pauls, Steffen U.

    2016-01-01

    Inland waters cover less than one percent of Earth’s surface, but harbor more than six percent of all insect species: nearly 100,000 species from 12 orders spend one or more life stages in freshwater. Little is known about how this remarkable diversity arose, although allopatric speciation and ecological adaptation are thought to be primary mechanisms. Freshwater habitats are exceptionally susceptible to environmental change, and exhibit marked ecological gradients. The amphibiotic lifestyles of aquatic insects result in complex contributions of extinction and allopatric and non-allopatric speciation in species diversification. In contrast to the lack of evolutionary studies, the ecology and habitat preferences of aquatic insects have been intensively studied, in part because of their widespread use as bio-indicators. The combination of phylogenetics with the extensive ecological data provides a promising avenue for future research, making aquatic insects highly suitable models for the study of ecological diversification. PMID:24160433

  6. Insect symbionts in food webs.

    PubMed

    McLean, Ailsa H C; Parker, Benjamin J; Hrček, Jan; Henry, Lee M; Godfray, H Charles J

    2016-09-01

    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

  7. Entomopathogenic nematodes and insect management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Entomopathogenic nematodes (genera Heterorhabditis, Steinernema, and Neosteinernema) are used as bioinsecticides. The nematodes are ubiquitous and have been isolated in soil of every continent except Antarctica. The nematodes kill insects through a mutualism with a bacterium (Photorhabdus spp. or ...

  8. Learning and cognition in insects.

    PubMed

    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.

  9. Radar Observation of Insects - Mosquitoes

    NASA Technical Reports Server (NTRS)

    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.

  10. Flight of the smallest insects

    NASA Astrophysics Data System (ADS)

    Miller, Laura; Santhanakrishnan, Arvind; Hedrick, Tyson; Robinson, Alice

    2009-11-01

    A vast body of research has described the complexity of flight in insects ranging from the fruit fly, Drosophila melanogaster, to the hawk moth, Manduca sexta. Over this range of scales, flight aerodynamics as well as the relative lift and drag forces generated are surprisingly similar. The smallest flying insects (Re˜10) have received far less attention, although previous work has shown that flight kinematics and aerodynamics can be significantly different. In this presentation, we have used a three-pronged approach that consists of measurements of flight kinematics in the tiny insect Thysanoptera (thrips), measurements of flow velocities using physical models, and direct numerical simulations to compute lift and drag forces. We find that drag forces can be an order of magnitude larger than lift forces, particularly during the clap and fling motion used by all tiny insects recorded to date.

  11. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of...

  12. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of...

  13. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of...

  14. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 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...

  15. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 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...

  16. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 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...

  17. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of...

  18. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    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...

  19. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of...

  20. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 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...

  1. How Do Insects Help the Environment?

    ERIC Educational Resources Information Center

    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,…

  2. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence...

  3. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence...

  4. Preface: Insect Pathology, 2nd ed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect pathology is an essential component of entomology and provides a non-chemical alternative for insect pest management. There are several groups of organisms that can infect and kill insects including viruses, fungi, microsporidia, bacteria, protists, and nematodes. The dilemma in insect patho...

  5. Spatial memory in insect navigation.

    PubMed

    Collett, Matthew; Chittka, Lars; Collett, Thomas S

    2013-09-01

    A wide variety of insects use spatial memories in behaviours like holding a position in air or flowing water, in returning to a place of safety, and in foraging. The Hymenoptera, in particular, have evolved life-histories requiring reliable spatial memories to support the task of provisioning their young. Behavioural experiments, primarily on social bees and ants, reveal the mechanisms by which these memories are employed for guidance to spatial goals and suggest how the memories, and the processing streams that use them, may be organized. We discuss three types of memory-based guidance which, together, can explain a large part of observed insect spatial behaviour. Two of these, alignment image-matching and positional image-matching, are based on an insect's remembered views of its surroundings: The first uses views to keep to a familiar heading and the second to head towards a familiar place. The third type of guidance is based on a process of path integration by which an insect monitors its distance and direction from its nest through odometric and compass information. To a large degree, these guidance mechanisms appear to involve modular computational systems. We discuss the lack of evidence for cognitive maps in insects, and in particular the evidence against a map based on path integration, in which view-based and path integration memories might be combined. We suggest instead that insects have a collective of separate guidance systems, which cooperate and train each other, and together provide reliable guidance over a range of conditions.

  6. Allergic reactions to insect stings and bites.

    PubMed

    Moffitt, John E

    2003-11-01

    Insect stings are an important cause of anaphylaxis. Anaphylaxis can also occur from insect bites but is less common. Insect venoms contain several well-characterized allergens that can trigger anaphylactic reactions. Effective methods to diagnose insect sting allergy and assess risk of future sting reactions have been developed. Management strategies using insect avoidance measures, self-injectable epinephrine, and allergen immunotherapy are very effective in reducing insect-allergic patients' risk of reaction from future stings. Diagnostic and management strategies for patients allergic to insect bites are less developed.

  7. Plant surfaces with cuticular folds and their replicas: influence of microstructuring and surface chemistry on the attachment of a leaf beetle.

    PubMed

    Prüm, Bettina; Florian Bohn, Holger; Seidel, Robin; Rubach, Stephan; Speck, Thomas

    2013-05-01

    Plant surfaces covered either with epicuticular wax crystals or cuticular folds have been shown to strongly reduce the ability of insects to attach to them. However, the relative impact of surface structuring vs. surface chemistry on insect attachment remains unclear. To understand the mechanisms reducing adhesion of insects on plant surfaces in more detail, we performed traction experiments (i) on plant surfaces covered with cuticular folds of different dimensions, and on their (ii) untreated and (iii) hydrophobized replicas. As a reference, measurements were performed on replicas of smooth plant surfaces and of glass. Traction forces were measured with a highly sensitive force transducer, using tethered male Colorado potato beetles (Leptinotarsa decemlineata) as a model insect species. Contact angle measurements with water and diiodomethane were also performed to examine the physicochemical properties of the test surfaces. We found that surface structuring has a strong influence on the magnitude of the attachment force. In contrast, under the chosen experimental conditions, surface chemistry had no significant influence. Our results indicate that attachment of the beetles is reduced solely by the dimensions of the folds, with cuticular folds of about 0.5 μm in both height and width being the most effective. Contrary to the attachment of beetles, the wettability of the surfaces was considerably influenced by both surface structuring and chemistry. These results contribute to a better understanding of plant-insect interactions and the function of microstructured surfaces, and may facilitate the development of biomimetic anti-adhesive surfaces. PMID:23391991

  8. Impact of host plant connectivity, crop border and patch size on adult Colorado potato beetle retention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tagged Colorado potato beetles (CPB), Leptinotarsa decemlineata (Say), were released on potato plants, Solanum tuberosum L., and tracked using a portable harmonic radar system to determine the impact of host plant spatial distribution on the tendency of the pest to remain on the colonized host plant...

  9. A protecting group-free synthesis of the Colorado potato beetle pheromone.

    PubMed

    Wu, Zhongtao; Jäger, Manuel; Buter, Jeffrey; Minnaard, Adriaan J

    2013-01-01

    A novel synthesis of the aggregation pheromone of the Colorado potato beetle, Leptinotarsa decemlineata, has been developed based on a Sharpless asymmetric epoxidation in combination with a chemoselective alcohol oxidation using catalytic [(neocuproine)PdOAc]2OTf2. Employing this approach, the pheromone was synthesized in 3 steps, 80% yield and 86% ee from geraniol. PMID:24367402

  10. Delayed efficacy of Beauveria bassiana foliar spray applications against Colorado potato beetle: impacts of number and timing of applications on larval and next-generation adult populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spray programs comprising multiple or single foliar applications of the fungal pathogen Beauveria bassiana strain GHA (Bb) made during morning (AM) vs. evening (PM) hours were tested against Colorado potato beetle Leptinotarsa decemlineata (CPB) in small research plots of potatoes over multiple fiel...

  11. Putative regulatory elements within the non-coding regions of Chrysomelidae Diapause Associated Transcript-1 (DAT-1) orthologs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To develop a more comprehensive understanding of diapause within Chrysomelidae, we are employing phylogenetic foot-printing to isolate and characterize the regulatory elements associated with the diapause-associated gene, DAT-1. Leptinotarsa decemlineata (Colorado potato beetle, CPB) DAT-1 has been ...

  12. A protecting group-free synthesis of the Colorado potato beetle pheromone.

    PubMed

    Wu, Zhongtao; Jäger, Manuel; Buter, Jeffrey; Minnaard, Adriaan J

    2013-01-01

    A novel synthesis of the aggregation pheromone of the Colorado potato beetle, Leptinotarsa decemlineata, has been developed based on a Sharpless asymmetric epoxidation in combination with a chemoselective alcohol oxidation using catalytic [(neocuproine)PdOAc]2OTf2. Employing this approach, the pheromone was synthesized in 3 steps, 80% yield and 86% ee from geraniol.

  13. Isolation of diapause-regulated transcripts by differential display from the Colorado potato beetle, and their expression in prediapausing and nondiapausing adults. GenBank. Accessions: FG591137-FG591192

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using differential display, 56 putatively diapause regulated transcripts were isolated from the Colorado potato beetle, Leptinotarsa decemlineata. The clones insert sizes range from 114 to 795 bp with mean length of 392 ± SD of 191 bp. Fourteen of the transcripts were confirmed by northern blot anal...

  14. Molecular characteristics of insect vitellogenins.

    PubMed

    Tufail, Muhammad; Takeda, Makio

    2008-12-01

    Vitellogenins (Vgs) are precursors of the major egg storage protein, vitellin (Vn), in many oviparous animals. Insects Vgs are large molecules ( approximately 200-kD) synthesized in the fat body in a process that involves substantial structural modifications (e.g., glycosylation, lipidation, phosphorylation, and proteolytic cleavage, etc.) of the nascent protein prior to its secretion and transport to the ovaries. However, the extent to which Vgs are processed in the fat body varies greatly among different insect groups. We provide evidence by cloning and peptide mapping of four Vg molecules from two cockroach species (Periplaneta americana and Leucophaea maderae) that, in hemimetabolous insects, the pro-Vg is cleaved into several polypeptides (ranging from 50-to 180-kD), unlike the holometabolans where the Vg precursor is cleaved into two polypeptides (one large and one small). An exception is the Vg of Apocrita (higher Hymenoptera) where the Vg gene product remains uncleaved. The yolk proteins (YPs) of higher Diptera (such as Drosophila) form a different family of proteins and are also not cleaved. So far, Vgs have been sequenced from 25 insect species; 9 of them belong to Hemimetabola and 16 to Holometabola. Alignment of the coding sequences revealed that some features, like the GL/ICG motif, cysteine residues, and a DGXR motif upstream of the GLI/CG motif, were highly conserved near the carboxy terminal of all insect Vgs. Moreover, a consensus RXXR cleavage sequence motif exists at the N-terminus of all sequences outside the Apocrita except for Lymantria dispar where it exists at the C-terminus. Phylogenetic analysis using 31 Vg sequences from 25 insect species reflects, in general, the current phylogenies of insects, suggesting that Vgs are still phylogenetically bound, although a divergence exists among them.

  15. Drosophila's view on insect vision.

    PubMed

    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.

  16. Insects as unidentified flying objects.

    PubMed

    Callahan, P S; Mankin, R W

    1978-11-01

    Five species of insects were subjected to a large electric field. Each of the insects stimulated in this manner emitted visible glows of various colors and blacklight (uv). It is postulated that the Uintah Basin, Utah, nocturnal UFO display (1965-1968) was partially due to mass swarms of spruce budworms, Choristoneura fumiferana (Clemens), stimulated to emit this type of St. Elmo's fire by flying into high electric fields caused by thunderheads and high density particulate matter in the air. There was excellent time and spatial correlation between the 1965-1968 UFO nocturnal sightings and spruce budworm infestation. It is suggested that a correlation of nocturnal UFO sightings throughout the U.S. and Canada with spruce budworm infestations might give some insight into nocturnal insect flight patterns.

  17. Neurosecretion: peptidergic systems in insects

    NASA Astrophysics Data System (ADS)

    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.

  18. Rice Reoviruses in Insect Vectors.

    PubMed

    Wei, Taiyun; Li, Yi

    2016-08-01

    Rice reoviruses, transmitted by leafhopper or planthopper vectors in a persistent propagative manner, seriously threaten the stability of rice production in Asia. Understanding the mechanisms that enable viral transmission by insect vectors is a key to controlling these viral diseases. This review describes current understanding of replication cycles of rice reoviruses in vector cell lines, transmission barriers, and molecular determinants of vector competence and persistent infection. Despite recent breakthroughs, such as the discoveries of actin-based tubule motility exploited by viruses to overcome transmission barriers and mutually beneficial relationships between viruses and bacterial symbionts, there are still many gaps in our knowledge of transmission mechanisms. Advances in genome sequencing, reverse genetics systems, and molecular technologies will help to address these problems. Investigating the multiple interaction systems among the virus, insect vector, insect symbiont, and plant during natural infection in the field is a central topic for future research on rice reoviruses. PMID:27296147

  19. Insects, infestations and nutrient fluxes

    NASA Astrophysics Data System (ADS)

    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

  20. Unsteady aerodynamics of insect flight.

    PubMed

    Ellington, C P

    1995-01-01

    Over the past decade, the importance of unsteady aerodynamic mechanisms for flapping insect flight has become widely recognised. Even at the fastest flight speeds, the old quasi-steady aerodynamic interpretation seems inadequate to explain the extra lift produced by the wings. Recent experiments on rigid model wings have confirmed the effectiveness of several postulated high-lift mechanisms. Delayed stall can produce extra lift for several chords of travel during the translational phases of the wingbeat. Lift can also be enhanced by circulation created during pronation and supination by rotational mechanisms: the fling/peel, the near fling/peel and isolated rotation. These studies have revealed large leading-edge vortices which contribute to the circulation around the wing, augmenting the lift. The mechanisms show distinctive patterns of vortex shedding from leading and trailing edges. The results of flow visualization experiments on tethered insects are reviewed in an attempt to identify the high-lift mechanisms actually employed. The fling/peel mechanism is clearly used by some insects. The near fling/peel is the wing motion most commonly observed, but evidence for the production of high lift remains indirect. For many insects, lift on the upstroke probably results from delayed stall instead of the flex mechanism of isolated rotation. The large leading-edge vortices from experiments on rigid model wings are greatly reduced or missing around the real insect wings, often making the identification of aerodynamic mechanisms inconclusive. A substantial spanwise flow component has been detected over the aerodynamic upper wing surface, which should transport leading-edge vorticity towards the wingtip before it has much time to roll up. This spanwise transport, arising from centrifugal acceleration, is probably a general phenomenon for flapping insect flight. It should reduce and stabilise any leading-edge vortices that are present, which is essential for preventing

  1. The evolution of insect societies.

    PubMed

    Page, R E

    1997-01-01

    The organization and evolution of insect societies has amazed natural historians since Aristotle. Charles Darwin considered social insects to be a major difficulty for his theory of evolution by natural selection because they demonstrate a rich diversity of adaptation among sterile workers leading to a complex division of labour, something that should not occur if variation in individual reproductive success is the grist for the mill of natural selection. This article shows how division of labour can self-organize from groups of cohabiting individuals without the necessity of a past history of natural selection for co-operative behaviour. It then explores how more complex social systems may evolve.

  2. Insect growth regulators and insect control: a critical appraisal.

    PubMed Central

    Siddall, J B

    1976-01-01

    Insect growth regulators (IGRs) of the juvenile hormone type alter physiological processes essential to insect development and appear to act specifically on insects. Three natural juvenile hormones have been found in insects but not in other organisms. Future use of antagonists or inhibitors of hormone synthesis may be technically possible as an advantageous extension of pest control by IGRs. A documented survey of the properties, metabolism, toxicology, and uses of the most commercially advanced chemical, methoprene, shows it to be environmentally acceptable and toxicologically innocuous. Derivation of its current use patterns is discussed and limitations on these are noted. Residue levels and their measurement in the ppb region have allowed exemption from the requirement of tolerances in the EPA registered use of methoprene for mosquito control. Tolerances for foods accompany its fully approved use for control of manure breeding flies through a cattle feed supplement. The human health effects of using this chemical appear to be purely beneficial, but further advances through new IGR chemicals appear unlikely without major changes in regulatory and legislative policy. PMID:976222

  3. Insects as a Nitrogen Source for Plants

    PubMed Central

    Behie, Scott W.; Bidochka, Michael J.

    2013-01-01

    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. PMID:26462427

  4. Insects as a Nitrogen Source for Plants.

    PubMed

    Behie, Scott W; Bidochka, Michael J

    2013-01-01

    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. PMID:26462427

  5. Insects as a Nitrogen Source for Plants.

    PubMed

    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.

  6. The Curious Connection Between Insects and Dreams

    PubMed Central

    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

  7. First Aid: Insect Stings and Bites

    MedlinePlus

    ... Can I Protect My Family From Ticks? Are Insect Repellents With DEET Safe for Kids? Bug Bites and Stings Can I Use Bug Killers and Repellents During Pregnancy? Insect Sting Allergy How Do I Watch for Lyme ...

  8. The Curious Connection Between Insects and Dreams.

    PubMed

    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.

  9. Introducing Virological Concepts Using an Insect Virus.

    ERIC Educational Resources Information Center

    Sheppard, Roger F.

    1980-01-01

    A technique is presented which utilizes wax moth larvae in a laboratory investigation of an insect virus. Describes how an insect virus can be used to introduce undergraduate biology students to laboratory work on viruses and several virological concepts. (SA)

  10. Palaeontology: Chinese amber insects bridge the gap.

    PubMed

    Ross, Andrew

    2014-07-21

    n the study of fossil insects, Chinese amber from Fushun has been largely overlooked. A new study now reveals a highly diverse biota and provides a wealth of new information on the past Asian insect fauna.

  11. Insects--How To Study Them

    ERIC Educational Resources Information Center

    Matthews, E. G.

    1975-01-01

    Describes an approach to the study of entomology directed at people with no special knowledge of insects. The aim of this approach is to reveal some biological principles by studying insects from an ecological point of view. (GS)

  12. The Seat of Insect Learning.

    ERIC Educational Resources Information Center

    Dyer, Fred C.

    1997-01-01

    Describes the role of mushroom bodies--cup-shaped structures perched atop the brain of an insect--in learning. Mushroom bodies may help fruit flies in learning meaningful odors, cockroaches in spatial learning, and honeybees both in locating pollen and nectar and in navigating back to the colony. (PVD)

  13. Insects Affecting Man. MP-21.

    ERIC Educational Resources Information Center

    Lawson, Fred A.; Spackman, Everett

    The insects discussed in this document are those which have a direct effect upon humans either through a permanent association, as with lice, or a temporary association in the case of flies, bees, wasps, and spiders. In each case, life cycles and identifying characteristics are presented with remarks about the specific effect incurred by man. (CS)

  14. Bug City: Aquatic Insects [Videotape].

    ERIC Educational Resources Information Center

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography, fun…

  15. Plant defense against insect herbivory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Damage to maize crops by insect herbivores such as beet and fall army worm causes significant impact in the Southern United States in terms of both yield loss and insecticide use. Enhanced understanding of how maize can defend itself against such attacks at a molecular level will enable development ...

  16. The insect SNMP gene family

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SNMPs are membrane proteins that have been shown to associate with chemosensory neurons in insects; in Drosophila melanogaster, SNMP1 has been shown to be essential for the detection of the pheromone cis vaccenyl acetate (Benton et al., 2001; Jin et al., 2008). To extend these observations to other ...

  17. Nontoxic Antifreeze for Insect Traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Propylene glycol in water is a safe and effective alternative to ethylene glycol as a capture liquid in insect traps (pitfalls, flight intercepts, pan traps). Propylene glycol formulations are readily available because it is the primary (95%) ingredient in certain automotive antifreeze formulations...

  18. Evolution of insect olfactory receptors

    PubMed Central

    Missbach, Christine; Dweck, Hany KM; Vogel, Heiko; Vilcinskas, Andreas; Stensmyr, Marcus C; Hansson, Bill S; Grosse-Wilde, Ewald

    2014-01-01

    The olfactory sense detects a plethora of behaviorally relevant odor molecules; gene families involved in olfaction exhibit high diversity in different animal phyla. Insects detect volatile molecules using olfactory (OR) or ionotropic receptors (IR) and in some cases gustatory receptors (GRs). While IRs are expressed in olfactory organs across Protostomia, ORs have been hypothesized to be an adaptation to a terrestrial insect lifestyle. We investigated the olfactory system of the primary wingless bristletail Lepismachilis y-signata (Archaeognatha), the firebrat Thermobia domestica (Zygentoma) and the neopteran leaf insect Phyllium siccifolium (Phasmatodea). ORs and the olfactory coreceptor (Orco) are with very high probability lacking in Lepismachilis; in Thermobia we have identified three Orco candidates, and in Phyllium a fully developed OR/Orco-based system. We suggest that ORs did not arise as an adaptation to a terrestrial lifestyle, but evolved later in insect evolution, with Orco being present before the appearance of ORs. DOI: http://dx.doi.org/10.7554/eLife.02115.001 PMID:24670956

  19. Transposable elements for insect transformation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The germ-line of more than 35 species from five orders of insects have been genetically transformed, using vectors derived from Class II transposable elements. Initially the P and hobo vector systems developed for D. melanogaster were not applicable to other species, but four transposons found in ot...

  20. Exaggerated trait growth in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal structures occasionally attain extreme proportions, eclipsing in size other, surrounding body parts. We review insect examples of exaggerated traits, such as the mandibles of stag beetles, the claspers of praying mantises, the elongated hindlimbs of grasshoppers, and the giant heads of soldie...

  1. Making Connections with Insect Royalty.

    ERIC Educational Resources Information Center

    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…

  2. Allergic reactions to insect secretions.

    PubMed

    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.

  3. Buckling failures in insect exoskeletons.

    PubMed

    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

  4. Antibacterial peptides isolated from insects.

    PubMed

    Otvos, L

    2000-10-01

    Insects are amazingly resistant to bacterial infections. To combat pathogens, insects rely on cellular and humoral mechanisms, innate immunity being dominant in the latter category. Upon detection of bacteria, a complex genetic cascade is activated, which ultimately results in the synthesis of a battery of antibacterial peptides and their release into the haemolymph. The peptides are usually basic in character and are composed of 20-40 amino acid residues, although some smaller proteins are also included in the antimicrobial repertoire. While the proline-rich peptides and the glycine-rich peptides are predominantly active against Gram-negative strains, the defensins selectively kill Gram-positive bacteria and the cecropins are active against both types. The insect antibacterial peptides are very potent: their IC50 (50% of the bacterial growth inhibition) hovers in the submicromolar or low micromolar range. The majority of the peptides act through disintegrating the bacterial membrane or interfering with membrane assembly, with the exception of drosocin, apidaecin and pyrrhocoricin which appear to deactivate a bacterial protein in a stereospecific manner. In accordance with their biological function, the membrane-active peptides form ordered structures, e.g. alpha-helices or beta-pleated sheets and often cast permeable ion-pores. Their cytotoxic properties were exploited in in vivo studies targeting tumour progression. Although the native peptides degrade quickly in biological fluids other than insect haemolymph, structural modifications render the peptides resistant against proteases without sacrificing biological activity. Indeed, a pyrrhocoricin analogue shows lack of toxicity in vitro and in vivo and protects mice against experimental Escherichia coli infection. Careful selection of lead molecules based on the insect antibacterial peptides may extend their utility and produce viable alternatives to the conventional antimicrobial compounds for mammalian therapy.

  5. Using new technology and insect behavior in novel terrestrial and flying insect traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect traps are commonly used for both population sampling and insect control, the former as part of an integrated pest management (IPM) program. We developed traps for two insects, one as part of a pesticide based IPM system and the other for population control. Our IPM trap is for crawling insect...

  6. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  7. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  8. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  9. Radar, Insect Population Ecology, and Pest Management

    NASA Technical Reports Server (NTRS)

    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.

  10. Insect Control (1): Use of Pheromones

    ERIC Educational Resources Information Center

    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)

  11. Applications of acoustics in insect pest management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acoustic technology has been applied for many years in studies of insect communication and in the monitoring of calling-insect population levels, geographic distributions, and diversity, as well as in the detection of cryptic insects in soil, wood, container crops, and stored products. Acoustic devi...

  12. Insect biomass to enhance food production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies have established that insects are as good source of protein as conventional animal food (between 15 and 67% dry weight content). Insects are a good source of essential amino acids and essential fatty acids. Insect fat has a higher content of polyunsaturated (essential) fatty acids and a lowe...

  13. Insect-machine interface based neurocybernetics.

    PubMed

    Bozkurt, Alper; Gilmour, Robert F; Sinha, Ayesa; Stern, David; Lal, Amit

    2009-06-01

    We present details of a novel bioelectric interface formed by placing microfabricated probes into insect during metamorphic growth cycles. The inserted microprobes emerge with the insect where the development of tissue around the electronics during the pupal development allows mechanically stable and electrically reliable structures coupled to the insect. Remarkably, the insects do not react adversely or otherwise to the inserted electronics in the pupae stage, as is true when the electrodes are inserted in adult stages. We report on the electrical and mechanical characteristics of this novel bioelectronic interface, which we believe would be adopted by many investigators trying to investigate biological behavior in insects with negligible or minimal traumatic effect encountered when probes are inserted in adult stages. This novel insect-machine interface also allows for hybrid insect-machine platforms for further studies. As an application, we demonstrate our first results toward navigation of flight in moths. When instrumented with equipment to gather information for environmental sensing, such insects potentially can assist man to monitor the ecosystems that we share with them for sustainability. The simplicity of the optimized surgical procedure we invented allows for batch insertions to the insect for automatic and mass production of such hybrid insect-machine platforms. Therefore, our bioelectronic interface and hybrid insect-machine platform enables multidisciplinary scientific and engineering studies not only to investigate the details of insect behavioral physiology but also to control it.

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

    PubMed

    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.

  15. Insect diversity in the fossil record

    NASA Technical Reports Server (NTRS)

    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.

  16. Insect diversity in the fossil record.

    PubMed

    Labandeira, C C; Sepkoski, J J

    1993-07-16

    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.

  17. Insects as alternative hosts for phytopathogenic bacteria.

    PubMed

    Nadarasah, Geetanchaly; Stavrinides, John

    2011-05-01

    Phytopathogens have evolved specialized pathogenicity determinants that enable them to colonize their specific plant hosts and cause disease, but their intimate associations with plants also predispose them to frequent encounters with herbivorous insects, providing these phytopathogens with ample opportunity to colonize and eventually evolve alternative associations with insects. Decades of research have revealed that these associations have resulted in the formation of bacterial-vector relationships, in which the insect mediates dissemination of the plant pathogen. Emerging research, however, has highlighted the ability of plant pathogenic bacteria to use insects as alternative hosts, exploiting them as they would their primary plant host. The identification of specific bacterial genetic determinants that mediate the interaction between bacterium and insect suggests that these interactions are not incidental, but have likely arisen following the repeated association of microorganisms with particular insects over evolutionary time. This review will address the biology and ecology of phytopathogenic bacteria that interact with insects, including the traditional role of insects as vectors, as well as the newly emerging paradigm of insects serving as alternative primary hosts. Also discussed is one case where an insect serves as both host and vector, which may represent a transitionary stage in the evolution of insect-phytopathogen associations.

  18. Fungal allelochemicals in insect pest management.

    PubMed

    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. PMID:27147531

  19. Insects as alternative hosts for phytopathogenic bacteria.

    PubMed

    Nadarasah, Geetanchaly; Stavrinides, John

    2011-05-01

    Phytopathogens have evolved specialized pathogenicity determinants that enable them to colonize their specific plant hosts and cause disease, but their intimate associations with plants also predispose them to frequent encounters with herbivorous insects, providing these phytopathogens with ample opportunity to colonize and eventually evolve alternative associations with insects. Decades of research have revealed that these associations have resulted in the formation of bacterial-vector relationships, in which the insect mediates dissemination of the plant pathogen. Emerging research, however, has highlighted the ability of plant pathogenic bacteria to use insects as alternative hosts, exploiting them as they would their primary plant host. The identification of specific bacterial genetic determinants that mediate the interaction between bacterium and insect suggests that these interactions are not incidental, but have likely arisen following the repeated association of microorganisms with particular insects over evolutionary time. This review will address the biology and ecology of phytopathogenic bacteria that interact with insects, including the traditional role of insects as vectors, as well as the newly emerging paradigm of insects serving as alternative primary hosts. Also discussed is one case where an insect serves as both host and vector, which may represent a transitionary stage in the evolution of insect-phytopathogen associations. PMID:21251027

  20. Fungal allelochemicals in insect pest management.

    PubMed

    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.

  1. Insect sodium channels and insecticide resistance

    PubMed Central

    2011-01-01

    Voltage-gated sodium channels are essential for the generation and propagation of action potentials (i.e., electrical impulses) in excitable cells. Although most of our knowledge about sodium channels is derived from decades of studies of mammalian isoforms, research on insect sodium channels is revealing both common and unique aspects of sodium channel biology. In particular, our understanding of the molecular dynamics and pharmacology of insect sodium channels has advanced greatly in recent years, thanks to successful functional expression of insect sodium channels in Xenopus oocytes and intensive efforts to elucidate the molecular basis of insect resistance to insecticides that target sodium channels. In this review, I discuss recent literature on insect sodium channels with emphases on the prominent role of alternative splicing and RNA editing in the generation of functionally diverse sodium channels in insects and the current understanding of the interactions between insect sodium channels and insecticides. PMID:17206406

  2. Conflict resolution in insect societies.

    PubMed

    Ratnieks, Francis L W; Foster, Kevin R; Wenseleers, Tom

    2006-01-01

    Although best known for cooperation, insect societies also manifest many potential conflicts among individuals. These conflicts involve both direct reproduction by individuals and manipulation of the reproduction of colony members. Here we review five major areas of reproductive conflict in insect societies: (a) sex allocation, (b) queen rearing, (c) male rearing, (d) queen-worker caste fate, and (e) breeding conflicts among totipotent adults. For each area we discuss the basis for conflict (potential conflict), whether conflict is expressed (actual conflict), whose interests prevail (conflict outcome), and the factors that reduce colony-level costs of conflict (conflict resolution), such as factors that cause workers to work rather than to lay eggs. Reproductive conflicts are widespread, sometimes having dramatic effects on the colony. However, three key factors (kinship, coercion, and constraint) typically combine to limit the effects of reproductive conflict and often lead to complete resolution.

  3. Corpse Management in Social Insects

    PubMed Central

    Sun, Qian; Zhou, Xuguo

    2013-01-01

    Undertaking behavior is an essential adaptation to social life that is critical for colony hygiene in enclosed nests. Social insects dispose of dead individuals in various fashions to prevent further contact between corpses and living members in a colony. Focusing on three groups of eusocial insects (bees, ants, and termites) in two phylogenetically distant orders (Hymenoptera and Isoptera), we review mechanisms of death recognition, convergent and divergent behavioral responses toward dead individuals, and undertaking task allocation from the perspective of division of labor. Distinctly different solutions (e.g., corpse removal, burial and cannibalism) have evolved, independently, in the holometabolous hymenopterans and hemimetabolous isopterans toward the same problem of corpse management. In addition, issues which can lead to a better understanding of the roles that undertaking behavior has played in the evolution of eusociality are discussed. PMID:23569436

  4. Visual homing: an insect perspective.

    PubMed

    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. PMID:22221863

  5. Unsteady Aerodynamics of Insect Flight

    NASA Astrophysics Data System (ADS)

    Wang, Z. Jane

    2000-03-01

    The myth `bumble-bees can not fly according to conventional aerodynamics' simply reflects our poor understanding of unsteady viscous fluid dynamics. In particular, we lack a theory of vorticity shedding due to dynamic boundaries at the intermediate Reynolds numbers relevant to insect flight, typically between 10^2 and 10^4, where both viscous and inertial effects are important. In our study, we compute unsteady viscous flows, governed by the Navier-Stokes equation, about a two dimensional flapping wing which mimics the motion of an insect wing. I will present two main results: the existence of a prefered frequency in forward flight and its physical origin, and 2) the vortex dynamics and forces in hovering dragonfly flight.

  6. Benzoquinolinediones: activity as insect teratogens

    SciTech Connect

    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.

  7. Visual Navigation in Nocturnal Insects.

    PubMed

    Warrant, Eric; Dacke, Marie

    2016-05-01

    Despite their tiny eyes and brains, nocturnal insects have evolved a remarkable capacity to visually navigate at night. Whereas some use moonlight or the stars as celestial compass cues to maintain a straight-line course, others use visual landmarks to navigate to and from their nest. These impressive abilities rely on highly sensitive compound eyes and specialized visual processing strategies in the brain. PMID:27053732

  8. Macroecology of local insect communities

    NASA Astrophysics Data System (ADS)

    Krüger, Oliver; McGavin, George C.

    2000-01-01

    The inter-relationships between animal body weight, range size, species richness and abundance are currently the basis of macroecology. Using 41 099 insects sampled from 31 Acacia tree canopies in north-east Tanzania, we first documented the basic macroecological patterns. The relationship between body weight and both species richness and abundance was polygonal with the highest insect species richness and abundance occurring at intermediate body weights. Across individual tree communities, the most statistically robust relationships were found between range size, abundance and species richness and they were all linear. In a second part, we focused on the positive abundance-range size relationship and we could test predictions of six of the eight proposed hypotheses to explain this widely documented pattern of community structure. The relationship is most likely explained by the metapopulation hypothesis stating that with more patches being occupied, local abundance in a given patch increases due to a higher rate of immigration from nearby patches. In addition, we found high slopes for the species-area relationship, typical of island systems and thus it seems reasonable to characterise Acacia trees in the savannah as habitat islands for insects.

  9. Herbivory increases diversification across insect clades.

    PubMed

    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.

  10. Interfacing insect brain for space applications.

    PubMed

    Di Pino, Giovanni; Seidl, Tobias; Benvenuto, Antonella; Sergi, Fabrizio; Campolo, Domenico; Accoto, Dino; Maria Rossini, Paolo; Guglielmelli, Eugenio

    2009-01-01

    Insects exhibit remarkable navigation capabilities that current control architectures are still far from successfully mimic and reproduce. In this chapter, we present the results of a study on conceptualizing insect/machine hybrid controllers for improving autonomy of exploratory vehicles. First, the different principally possible levels of interfacing between insect and machine are examined followed by a review of current approaches towards hybridity and enabling technologies. Based on the insights of this activity, we propose a double hybrid control architecture which hinges around the concept of "insect-in-a-cockpit." It integrates both biological/artificial (insect/robot) modules and deliberative/reactive behavior. The basic assumption is that "low-level" tasks are managed by the robot, while the "insect intelligence" is exploited whenever high-level problem solving and decision making is required. Both neural and natural interfacing have been considered to achieve robustness and redundancy of exchanged information.

  11. Herbivory increases diversification across insect clades

    PubMed Central

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

    2015-01-01

    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. PMID:26399434

  12. Raindrops push and splash flying insects

    NASA Astrophysics Data System (ADS)

    Dickerson, Andrew K.; Shankles, Peter G.; Hu, David L.

    2014-02-01

    In their daily lives, flying insects face a gauntlet of environmental challenges, from wind gusts to raindrop impacts. In this combined experimental and theoretical study, we use high-speed videography to film raindrop collisions upon both flying insects and dynamically scaled spherical mimics. We identify three outcomes of the collision based upon the insect's mass and characteristic size: drops push the insect while remaining intact, coat the insect, and splash. We present a mathematical model that predicts impact force and outcome consistent with those found in experiments. Small insects such as gnats and flies are pushed by raindrops that remain intact upon impact; conversely, large flyers such as locusts and micro-aerial vehicles cause drops to splash. We identify a critical mass of 0.3 g for which flyers achieve both peak acceleration (100 g) and applied force (104 dyn) from incoming raindrops; designs of similarly massed flying robots should be avoided.

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

    PubMed

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

    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 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. PMID:26740144

  14. Insect stereopsis demonstrated using a 3D insect cinema

    PubMed Central

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

    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 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. PMID:26740144

  15. Feeling what an insect feels.

    PubMed

    Mohand Ousaid, Abdenbi; Millet, Guillaume; Haliyo, Sinan; Régnier, Stéphane; Hayward, Vincent

    2014-01-01

    We describe a manually operated, bilateral mechanical scaling instrument that simultaneously magnifies microscopic forces and reduces displacements with quasi-perfect transparency. In contrast with existing micro-teleoperation designs, the system is unconditionally stable for any scaling gains and interaction curves. In the present realization, the work done by the hand is more than a million times that done by a microscopic probe so that one can feel complete interaction cycles with water and compare them to what is felt when an insect leg interacts with a wet surface.

  16. Feeling What an Insect Feels

    PubMed Central

    Mohand Ousaid, Abdenbi; Millet, Guillaume; Haliyo, Sinan; Régnier, Stéphane; Hayward, Vincent

    2014-01-01

    We describe a manually operated, bilateral mechanical scaling instrument that simultaneously magnifies microscopic forces and reduces displacements with quasi-perfect transparency. In contrast with existing micro-teleoperation designs, the system is unconditionally stable for any scaling gains and interaction curves. In the present realization, the work done by the hand is more than a million times that done by a microscopic probe so that one can feel complete interaction cycles with water and compare them to what is felt when an insect leg interacts with a wet surface. PMID:25271636

  17. Active Auditory Mechanics in Insects

    NASA Astrophysics Data System (ADS)

    Robert, D.; Göpfert, M. C.

    2003-02-01

    Evidence is presented that hearing in some insects is an active process. Audition in mosquitoes is used for mate-detection and is supported by antennal receivers, whose sound-induced vibrations are transduced by Johnston's organs. Each of these sensory organs contains ca. 15,000 sensory neurons. As shown by mechanical analysis, a physiologically vulnerable mechanism is at work that nonlinearly enhances the sensitivity and frequency selectivity of antennal hearing. This process of amplification correlates with the electrical activity of the auditory mechanoreceptor units in Johnston's organ.

  18. Feeling what an insect feels.

    PubMed

    Mohand Ousaid, Abdenbi; Millet, Guillaume; Haliyo, Sinan; Régnier, Stéphane; Hayward, Vincent

    2014-01-01

    We describe a manually operated, bilateral mechanical scaling instrument that simultaneously magnifies microscopic forces and reduces displacements with quasi-perfect transparency. In contrast with existing micro-teleoperation designs, the system is unconditionally stable for any scaling gains and interaction curves. In the present realization, the work done by the hand is more than a million times that done by a microscopic probe so that one can feel complete interaction cycles with water and compare them to what is felt when an insect leg interacts with a wet surface. PMID:25271636

  19. Insect Seminal Fluid Proteins: Identification and Function

    PubMed Central

    Avila, Frank W.; Sirot, Laura K.; LaFlamme, Brooke A.; Rubinstein, C. Dustin; Wolfner, Mariana F.

    2014-01-01

    Seminal fluid proteins (SFPs) produced in reproductive tract tissues of male insects and transferred to females during mating induce numerous physiological and behavioral post-mating changes in females. These changes include decreasing receptivity to re-mating, affecting sperm storage parameters, increasing egg production, modulating sperm competition, feeding behaviors, and mating plug formation. In addition, SFPs also have anti-microbial functions and induce expression of anti-microbial peptides in at least some insects. Here, we review recent identification of insect SFPs and discuss the multiple roles these proteins play in the post-mating processes of female insects. PMID:20868282

  20. Insect Antimicrobial Peptides and Their Applications

    PubMed Central

    Yi, Hui-Yu; Chowdhury, Munmun; Huang, Ya-Dong; Yu, Xiao-Qiang

    2014-01-01

    Insects are one of the major sources of antimicrobial peptides/proteins (AMPs). Since observation of antimicrobial activity in the hemolymph of pupae from the giant silk moths Samia Cynthia and Hyalophora cecropia in 1974 and purification of first insect AMP (cecropin) from H. cecropia pupae in 1980, over 150 insect AMPs have been purified or identified. Most insect AMPs are small and cationic, and they show activities against bacteria and/or fungi, as well as some parasites and viruses. Insect AMPs can be classified into four families based on their structures or unique sequences: the α-helical peptides (cecropin and moricin), cysteine-rich peptides (insect defensin and drosomycin), proline-rich peptides (apidaecin, drosocin and lebocin), and glycine-rich peptides/proteins (attacin and gloverin). Among insect AMPs, defensins, cecropins, proline-rich peptides and attacins are common, while gloverins and moricins have been identified only in Lepidoptera. Most active AMPs are small peptides of 20–50 residues, which are generated from larger inactive precursor proteins or pro-proteins, but gloverins (~14 kDa) and attacins (~20 kDa) are large antimicrobial proteins. In this mini-review, we will discuss current knowledge and recent progress in several classes of insect AMPs, including insect defensins, cecropins, attacins, lebocins and other proline-rich peptides, gloverins, and moricins, with a focus on structural-functional relationships and their potential applications. PMID:24811407

  1. Treatment and prevention of insect bites: mosquitoes.

    PubMed

    Williams, LaVonn A; Allen, Loyd V

    2012-01-01

    Insect bites are a common complaint of patients during the summer months, when more time is spent enjoying the warm weather. While most reactions to insect bites are mild, in rare cases, a severe allergic reaction may occur. In addition, certain insects may transmit potentially serious diseases. Counseling patients on the proper use of insect repellants and good first aid techniques can significantly reduce the risks posed by the presence of summertime pests. This article focuses on mosquitoes, the diseases they spread, and suggested treatments.

  2. Resistant potato selections contain leptine and inhibit development of the Colorado potato beetle (Coleoptera: Chrysomelidae).

    PubMed

    Lorenzen, J H; Balbyshev, N F; Lafta, A M; Casper, H; Tian, X; Sagredo, B

    2001-10-01

    We recently described a new source of host-plant resistance to the Colorado potato beetle, Leptinotarsa decemlineata (Say), in a tetraploid potato (Solanum tuberosum L.) selection, ND2858-1. This genotype, and selected backcross progeny, had little damage while check cultivars were defoliated in open-choice field assays. To further characterize the observed deterrence, we determined foliar glycoalkaloids and conducted no-choice assays with ND2858-1 backcross progeny genotypes (ND4382-n). Development of neonate L. decemlineata in detached leaf assays on resistant progeny genotypes was delayed and larval weight gain after 4 d was inhibited by 75% relative to larval development and weight gain on susceptible genotypes. Inhibition of larval development in detached leaf assays with the selected progeny genotypes was equivalent to that of high-leptine genotypes of S. chacoense Bitter. Foliar glycoalkaloids of resistant genotypes included low levels of leptines I and II. The unlikely nature of this cross and the presence of leptine in this and resistant progeny selections cast doubt on the recorded pedigree. Molecular analyses were conducted by restriction fragment-length polymorphism and amplified fragment-length polymorphisms. Both methods established a high degree of relatedness to S. tuberososum and S. chacoense but not to S. fendleri. We conclude that ND2858-1 did not originate from a cross with S. fendleri, but is likely derived from S. chacoense. Oviposition and larval survival were reduced when adult L. decemlineata were placed in cages with resistant genotypes; an effect that was enhanced by inclusion of Perillus bioculatus F. Therefore, the nonpreference previously observed in open-choice field defoliation assays is also associated with antibiotic effects on L. decemlineata. The resistance may be caused by leptines, but is greater than would be expected by the leptine content. This source of host plant resistance could be a cost-effective management strategy

  3. Smads and insect hemimetabolan metamorphosis.

    PubMed

    Santos, Carolina G; Fernandez-Nicolas, Ana; Belles, Xavier

    2016-09-01

    In contrast with Drosophila melanogaster, practically nothing is known about the involvement of the TGF-β signaling pathway in the metamorphosis of hemimetabolan insects. To partially fill this gap, we have studied the role of Smad factors in the metamorphosis of the German cockroach, Blattella germanica. In D. melanogaster, Mad is the canonical R-Smad of the BMP branch of the TGF-β signaling pathway, Smox is the canonical R-Smad of the TGF-β/Activin branch and Medea participates in both branches. In insects, metamorphosis is regulated by the MEKRE93 pathway, which starts with juvenile hormone (JH), whose signal is transduced by Methoprene-tolerant (Met), which stimulates the expression of Krüppel homolog 1 (Kr-h1) that acts to repress E93, the metamorphosis trigger. In B. germanica, metamorphosis is determined at the beginning of the sixth (final) nymphal instar (N6), when JH production ceases, the expression of Kr-h1 declines, and the transcription of E93 begins to increase. The RNAi of Mad, Smox and Medea in N6 of B. germanica reveals that the BMP branch of the TGF-β signaling pathway regulates adult ecdysis and wing extension, mainly through regulating the expression of bursicon, whereas the TGF-β/Activin branch contributes to increasing E93 and decreasing Kr-h1 at the beginning of N6, crucial for triggering adult morphogenesis, as well as to regulating the imaginal molt timing. PMID:27452629

  4. What Do Elementary Students Know about Insects?

    ERIC Educational Resources Information Center

    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)

  5. Applications of genome editing in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  6. Eric Carle-Inspired Insect Collages.

    ERIC Educational Resources Information Center

    Palamountain, Eileen; Turner, Kim

    2000-01-01

    Describes a lesson in which students create collage insects inspired by the work of Eric Carle (The Very Hungry Caterpillar). Connects art, language arts, and science. Discusses how students make paper to use as the collage material and how students create the insects. (CMK)

  7. Eicosanoids: Progress Toward Manipulating Insect Immunity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  8. Insect cadaver applications: pros and cons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Application of entomopathogenic nematodes (EPNs) formulated as insect cadavers has become an alternative to aqueous application for the control of agricultural pests. In this approach, the infected insect host cadaver is applied directly to the target site and pest suppression is achieved by the inf...

  9. Estimating Aquatic Insect Populations. Introduction to Sampling.

    ERIC Educational Resources Information Center

    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);…

  10. Towards the elements of successful insect RNAi

    PubMed Central

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

    2013-01-01

    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. PMID:24041495

  11. Secondary succession: insect-plant relationships

    SciTech Connect

    Brown, V.K.

    1984-12-01

    Botanists have dominated the study of secondary succession, and as a result, models and theories have focused on plants. Recent work, however, has revealed several complex relationships between plants and insects during succession, including adaptations of life-cycle strategies. Furthermore, insect herbivores play a key role in the course and rate of plant succession.

  12. Testing mechanistic models of growth in insects.

    PubMed

    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.

  13. Applications of genome editing in insects.

    PubMed

    Reid, William; O'Brochta, David A

    2016-02-01

    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 insects to date have been technical in nature but this is rapidly changing. Functional genomics and genetics-based insect control efforts will be major beneficiaries of the application of contemporary gene editing technologies. Engineered endonucleases like Cas9 make it possible to create powerful and effective gene drive systems that could be used to reduce or even eradicate specific insect populations. 'Best practices' for using Cas9-based editing are beginning to emerge making it easier and more effective to design and use but gene editing technologies still require traditional means of delivery in order to introduce them into somatic and germ cells of insects-microinjection of developing embryos. This constrains the use of these technologies by insect scientists. Insects created using editing technologies challenge existing governmental regulatory structures designed to manage genetically modified organisms.

  14. 2008 Sunflower Insect Trap Monitoring Network

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A regional insect trap network was developed by the National Sunflower Association, USDA-ARS, and North Dakota State University Extension Service to monitor for two major insect pests of sunflower in 2008 including the sunflower moth, Homoeosoma electellum (Hulst) (Lepidoptera: Pyralidae) and the b...

  15. Genomics of Insect-Soybean Interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dissection of plant-insect interactions has lagged behind that of interactions between plants and other types of pests. Insect pests interact with plants in a variety of ways, ranging from piercing and sucking of phloem to consumption of leaves and other tissues. Hence, a wide range of genetic m...

  16. Diversity in Protein Glycosylation among Insect Species

    PubMed Central

    Vandenborre, Gianni; Smagghe, Guy; Ghesquière, Bart; Menschaert, Gerben; Nagender Rao, Rameshwaram; Gevaert, Kris; Van Damme, Els J. M.

    2011-01-01

    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. PMID:21373189

  17. Perspectives on the state of insect transgenics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic transformation is a critical component to the fundamental genetic analysis of insect species, and holds great promise for establishing strains that improve population control and behavior for practical application. This is especially so for insects that are disease vectors, many of which a...

  18. Applications of genome editing in insects.

    PubMed

    Reid, William; O'Brochta, David A

    2016-02-01

    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 insects to date have been technical in nature but this is rapidly changing. Functional genomics and genetics-based insect control efforts will be major beneficiaries of the application of contemporary gene editing technologies. Engineered endonucleases like Cas9 make it possible to create powerful and effective gene drive systems that could be used to reduce or even eradicate specific insect populations. 'Best practices' for using Cas9-based editing are beginning to emerge making it easier and more effective to design and use but gene editing technologies still require traditional means of delivery in order to introduce them into somatic and germ cells of insects-microinjection of developing embryos. This constrains the use of these technologies by insect scientists. Insects created using editing technologies challenge existing governmental regulatory structures designed to manage genetically modified organisms. PMID:27436552

  19. Permian insect wing from antarctic sentinel mountains.

    PubMed

    Tasch, P; Riek, E F

    1969-06-27

    A homopterous insect wing was found in micaceous graywacke from the Polarstar Formation, Sentinel Mountains. The unusual venation is reminiscent of family Stenoviciidae known from the Permian and Triassic of Eastern Australia and elsewhere. This first documented account of Paleozoic insects in Antarctica bears on drift questions. PMID:17748532

  20. Insects and Spiders. Environmental Education Curriculum.

    ERIC Educational Resources Information Center

    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…

  1. Potential applications of insect symbionts in biotechnology.

    PubMed

    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.

  2. Biological control of potato insect pest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of pest insects attack the potato crop and reduce yields. This book chapter reviews the known insect natural enemies for major potato pests around the world: Coleoptera (beetles) including Colorado potato beetle, 28-spotted lady beetle, and Andean potato weevil complex; potato tuber moths,...

  3. Multiorganismal Insects: Diversity and Function of Resident Microorganisms

    PubMed Central

    Douglas, Angela E.

    2015-01-01

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests. PMID:25341109

  4. Multiorganismal insects: diversity and function of resident microorganisms.

    PubMed

    Douglas, Angela E

    2015-01-01

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests. PMID:25341109

  5. CHARACTERIZATION OF MICROBIAL GUT FLORA OF HETEROPTEROUS INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many insects harbor a robust complement of prokaryotes in their alimentary canals. These microorganisms may facilitate nutrient availability and utilization, detoxification of environmental toxins, or play other important roles in the insect's life history. Understanding insect-microorganism inter...

  6. Multiorganismal insects: diversity and function of resident microorganisms.

    PubMed

    Douglas, Angela E

    2015-01-01

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests.

  7. The smallest insects evolve anucleate neurons.

    PubMed

    Polilov, Alexey A

    2012-01-01

    The smallest insects are comparable in size to unicellular organisms. Thus, their size affects their structure not only at the organ level, but also at the cellular level. Here we report the first finding of animals with an almost entirely anucleate nervous system. Adults of the smallest flying insects of the parasitic wasp genus Megaphragma (Hymenoptera: Trichogrammatidae) have only 339-372 nuclei in the central nervous system, i.e., their ganglia, including the brain, consist almost exclusively of processes of neurons. In contrast, their pupae have ganglia more typical of other insects, with about 7400 nuclei in the central nervous system. During the final phases of pupal development, most neuronal cell bodies lyse. As adults, these insects have many fewer nucleated neurons, a small number of cell bodies in different stages of lysis, and about 7000 anucleate cells. Although most neurons lack nuclei, these insects exhibit many important behaviors, including flight and searching for hosts.

  8. Symbiont-mediated functions in insect hosts

    PubMed Central

    Su, Qi; Zhou, Xiaomao; Zhang, Youjun

    2013-01-01

    The bacterial endosymbionts occur in a diverse array of insect species and are usually rely within the vertical transmission from mothers to offspring. In addition to primary symbionts, plant sap-sucking insects may also harbor several diverse secondary symbionts. Bacterial symbionts play a prominent role in insect nutritional ecology by aiding in digestion of food or supplementing nutrients that insect hosts can’t obtain sufficient amounts from a restricted diet of plant phloem. Currently, several other ecologically relevant traits mediated by endosymbionts are being investigated, including defense toward pathogens and parasites, adaption to environment, influences on insect-plant interactions, and impact of population dynamics. Here, we review recent theoretical predictions and experimental observations of these traits mediated by endosymbionts and suggest that clarifying the roles of symbiotic microbes may be important to offer insights for ameliorating pest invasiveness or impact. PMID:23710278

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

    USGS Publications Warehouse

    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.

  10. Evolutionary ecology of periodical insects.

    PubMed

    Heliövaara, K; Väisänen, R; Simon, C

    1994-12-01

    To be periodical, a species must have a fixed life cycle length and adults must appear synchronously, reproduce only once, and die. The consequence of this life history is that, at a given location, adults of a periodical species will be absent or rare in some years and abundant in others. The relative scarcity of periodical Insect species suggests that periodicity does not evolve easily. The major obstacle to its evolution is selection favoring life cycles In which the offspring of any given female appear over a two- or three-year period. Chance events which disrupt this 'bet-hedging' strategy set the stage for periodicity. Mathematical models predict that, given certain initial conditions, intraspecific competition and predation favor its development. Recent studies suggest that periodicity is rarely perfect but that it can persist in the face of limited gene flow through time.

  11. Neural mechanisms of insect navigation.

    PubMed

    Webb, Barbara; Wystrach, Antoine

    2016-06-01

    We know more about the ethology of insect navigation than the neural substrates. Few studies have shown direct effects of brain manipulation on navigational behaviour; or measure brain responses that clearly relate to the animal's current location or spatial target, independently of specific sensory cues. This is partly due to the methodological problems of obtaining neural data in a naturally behaving animal. However, substantial indirect evidence, such as comparative anatomy and knowledge of the neural circuits that provide relevant sensory inputs provide converging arguments for the role of some specific brain areas: the mushroom bodies; and the central complex. Finally, modelling can help bridge the gap by relating the computational requirements of a given navigational task to the type of computation offered by different brain areas. PMID:27436729

  12. Exaggerated trait growth in insects.

    PubMed

    Lavine, Laura; Gotoh, Hiroki; Brent, Colin S; Dworkin, Ian; Emlen, Douglas J

    2015-01-01

    Animal structures occasionally attain extreme proportions, eclipsing in size the surrounding body parts. We review insect examples of exaggerated traits, such as the mandibles of stag beetles (Lucanidae), the claspers of praying mantids (Mantidae), the elongated hindlimbs of grasshoppers (Orthoptera: Caelifera), and the giant heads of soldier ants (Formicidae) and termites (Isoptera). Developmentally, disproportionate growth can arise through trait-specific modifications to the activity of at least four pathways: the sex determination pathway, the appendage patterning pathway, the insulin/IGF signaling pathway, and the juvenile hormone/ecdysteroid pathway. Although most exaggerated traits have not been studied mechanistically, it is already apparent that distinct developmental mechanisms underlie the evolution of the different types of exaggerated traits. We suggest this reflects the nature of selection in each instance, revealing an exciting link between mechanism, form, and function. We use this information to make explicit predictions for the types of regulatory pathways likely to underlie each type of exaggerated trait.

  13. An Automated Flying-Insect-Detection System

    NASA Technical Reports Server (NTRS)

    Vann, Timi; Andrews, Jane C.; Howell, Dane; Ryan, Robert

    2005-01-01

    An automated flying-insect-detection system (AFIDS) was developed as a proof-of-concept instrument for real-time detection and identification of flying insects. This type of system has use in public health and homeland security decision support, agriculture and military pest management, and/or entomological research. Insects are first lured into the AFIDS integrated sphere by insect attractants. Once inside the sphere, the insect's wing beats cause alterations in light intensity that is detected by a photoelectric sensor. Following detection, the insects are encouraged (with the use of a small fan) to move out of the sphere and into a designated insect trap where they are held for taxonomic identification or serological testing. The acquired electronic wing beat signatures are preprocessed (Fourier transformed) in real-time to display a periodic signal. These signals are sent to the end user where they are graphically displayed. All AFIDS data are pre-processed in the field with the use of a laptop computer equipped with LABVIEW. The AFIDS software can be programmed to run continuously or at specific time intervals when insects are prevalent. A special DC-restored transimpedance amplifier reduces the contributions of low-frequency background light signals, and affords approximately two orders of magnitude greater AC gain than conventional amplifiers. This greatly increases the signal-to-noise ratio and enables the detection of small changes in light intensity. The AFIDS light source consists of high-intensity Al GaInP light-emitting diodes (LEDs). The AFIDS circuitry minimizes brightness fluctuations in the LEDs and when integrated with an integrating sphere, creates a diffuse uniform light field. The insect wing beats isotropically scatter the diffuse light in the sphere and create wing beat signatures that are detected by the sensor. This configuration minimizes variations in signal associated with insect flight orientation.

  14. The earliest known holometabolous insects.

    PubMed

    Nel, André; Roques, Patrick; Nel, Patricia; Prokin, Alexander A; Bourgoin, Thierry; Prokop, Jakub; Szwedo, Jacek; Azar, Dany; Desutter-Grandcolas, Laure; Wappler, Torsten; Garrouste, Romain; Coty, David; Huang, Diying; Engel, Michael S; Kirejtshuk, Alexander G

    2013-11-14

    The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera) have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola (Supplementary Information); the earliest definitive beetles are from the start of the Permian period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils--a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age--and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian-Moscovian and the Kasimovian-Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era 'giant' insects. Although these discoveries reveal unexpected Pennsylvanian

  15. The earliest known holometabolous insects.

    PubMed

    Nel, André; Roques, Patrick; Nel, Patricia; Prokin, Alexander A; Bourgoin, Thierry; Prokop, Jakub; Szwedo, Jacek; Azar, Dany; Desutter-Grandcolas, Laure; Wappler, Torsten; Garrouste, Romain; Coty, David; Huang, Diying; Engel, Michael S; Kirejtshuk, Alexander G

    2013-11-14

    The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera) have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola (Supplementary Information); the earliest definitive beetles are from the start of the Permian period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils--a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age--and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian-Moscovian and the Kasimovian-Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era 'giant' insects. Although these discoveries reveal unexpected Pennsylvanian

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

    PubMed

    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.

  17. Extraordinary Adaptive Plasticity of Colorado Potato Beetle: “Ten-Striped Spearman” in the Era of Biotechnological Warfare

    PubMed Central

    Cingel, Aleksandar; Savić, Jelena; Lazarević, Jelica; Ćosić, Tatjana; Raspor, Martin; Smigocki, Ann; Ninković, Slavica

    2016-01-01

    Expanding from remote areas of Mexico to a worldwide scale, the ten-striped insect, the Colorado potato beetle (CPB, Leptinotarsa decemlineata Say), has risen from being an innocuous beetle to a prominent global pest. A diverse life cycle, phenotypic plasticity, adaptation to adverse conditions, and capability to detoxify or tolerate toxins make this insect appear to be virtually “indestructible”. With increasing advances in molecular biology, tools of biotechnological warfare were deployed to combat CPB. In the last three decades, genetically modified potato has created a new challenge for the beetle. After reviewing hundreds of scientific papers dealing with CPB control, it became clear that even biotechnological means of control, if used alone, would not defeat the Colorado potato beetle. This control measure once again appears to be provoking the potato beetle to exhibit its remarkable adaptability. Nonetheless, the potential for adaptation to these techniques has increased our knowledge of this pest and thus opened possibilities for devising more sustainable CPB management programs. PMID:27649141

  18. Herbivory responsive C2H2 zinc finger transcription factor protein StZFP2 from potato.

    PubMed

    Lawrence, Susan D; Novak, Nicole G; Jones, Richard W; Farrar, Robert R; Blackburn, Michael B

    2014-07-01

    While C2H2 zinc finger transcription factors (TF) are often regulated by abiotic stress, their role during insect infestation has been overlooked. This study demonstrates that the transcripts of the zinc finger transcription factors StZFP1 and StZFP2 are induced in potato (Solanum tuberosum L.) upon infestation by either the generalist tobacco hornworm (THW, Manduca sexta L.) or the specialist Colorado potato beetle (CPB, Leptinotarsa decemlineata Say). StZFP1 has been previously characterized as conferring salt tolerance to transgenic tobacco and its transcript is induced by Phytophthora infestans and several abiotic stresses. StZFP2 has not been characterized previously, but contains the hallmarks of a C2H2 zinc finger TF, with two conserved zinc finger domains and DLN motif, which encodes a transcriptional repressor domain. Expression studies demonstrate that StZFP2 transcript is also induced by tobacco hornworm and Colorado potato beetle. These observations expand the role of the C2H2 transcription factor in potato to include the response to chewing insect pests. PMID:24811678

  19. The involvement of clathrin-mediated endocytosis and two Sid-1-like transmembrane proteins in double-stranded RNA uptake in the Colorado potato beetle midgut.

    PubMed

    Cappelle, K; de Oliveira, C F R; Van Eynde, B; Christiaens, O; Smagghe, G

    2016-06-01

    RNA interference (RNAi) is a powerful tool in entomology and shows promise as a crop protection strategy, but variability in its efficiency across different insect species limits its applicability. For oral uptake of the double-stranded RNA (dsRNA), the RNAi trigger, two different mechanisms are known: systemic RNA interference deficient-1 (Sid-1) transmembrane channel-mediated uptake and clathrin-mediated endocytosis. So far, a wide range of experiments has been conducted, confirming the involvement of one of the pathways in dsRNA uptake, but never both pathways in the same species. We investigated the role of both pathways in dsRNA uptake in the Colorado potato beetle, Leptinotarsa decemlineata, known to have an efficient RNAi response. Through RNAi-of-RNAi experiments, we demonstrated the contribution of two different sid-1-like (sil) genes, silA and silC, and clathrin heavy chain and the 16kDa subunit of the vacuolar H(+) ATPase (vha16), elements of the endocytic pathway, to the RNAi response. Furthermore, the sid-1-like genes were examined through phylogenetic and hydrophobicity analysis. This article reports for the first time on the involvement of two pathways in dsRNA uptake in an insect species and stresses the importance of evaluating both pathways through a well-devised reporter system in any future experiments on cellular dsRNA uptake. PMID:26959524

  20. Herbivore exploits orally secreted bacteria to suppress plant defenses.

    PubMed

    Chung, Seung Ho; Rosa, Cristina; Scully, Erin D; Peiffer, Michelle; Tooker, John F; Hoover, Kelli; Luthe, Dawn S; Felton, Gary W

    2013-09-24

    Induced plant defenses in response to herbivore attack are modulated by cross-talk between jasmonic acid (JA)- and salicylic acid (SA)-signaling pathways. Oral secretions from some insect herbivores contain effectors that overcome these antiherbivore defenses. Herbivores possess diverse microbes in their digestive systems and these microbial symbionts can modify plant-insect interactions; however, the specific role of herbivore-associated microbes in manipulating plant defenses remains unclear. Here, we demonstrate that Colorado potato beetle (Leptinotarsa decemlineata) larvae exploit bacteria in their oral secretions to suppress antiherbivore defenses in tomato (Solanum lycopersicum). We found that antibiotic-untreated larvae decreased production of JA and JA-responsive antiherbivore defenses, but increased SA accumulation and SA-responsive gene expression. Beetles benefit from down-regulating plant defenses by exhibiting enhanced larval growth. In SA-deficient plants, suppression was not observed, indicating that suppression of JA-regulated defenses depends on the SA-signaling pathway. Applying bacteria isolated from larval oral secretions to wounded plants confirmed that three microbial symbionts belonging to the genera Stenotrophomonas, Pseudomonas, and Enterobacter are responsible for defense suppression. Additionally, reinoculation of these bacteria to antibiotic-treated larvae restored their ability to suppress defenses. Flagellin isolated from Pseudomonas sp. was associated with defense suppression. Our findings show that the herbivore exploits symbiotic bacteria as a decoy to deceive plants into incorrectly perceiving the threat as microbial. By interfering with the normal perception of herbivory, beetles can evade antiherbivore defenses of its host. PMID:24019469

  1. Herbivore exploits orally secreted bacteria to suppress plant defenses

    PubMed Central

    Chung, Seung Ho; Rosa, Cristina; Scully, Erin D.; Peiffer, Michelle; Tooker, John F.; Hoover, Kelli; Luthe, Dawn S.; Felton, Gary W.

    2013-01-01

    Induced plant defenses in response to herbivore attack are modulated by cross-talk between jasmonic acid (JA)- and salicylic acid (SA)-signaling pathways. Oral secretions from some insect herbivores contain effectors that overcome these antiherbivore defenses. Herbivores possess diverse microbes in their digestive systems and these microbial symbionts can modify plant–insect interactions; however, the specific role of herbivore-associated microbes in manipulating plant defenses remains unclear. Here, we demonstrate that Colorado potato beetle (Leptinotarsa decemlineata) larvae exploit bacteria in their oral secretions to suppress antiherbivore defenses in tomato (Solanum lycopersicum). We found that antibiotic-untreated larvae decreased production of JA and JA-responsive antiherbivore defenses, but increased SA accumulation and SA-responsive gene expression. Beetles benefit from down-regulating plant defenses by exhibiting enhanced larval growth. In SA-deficient plants, suppression was not observed, indicating that suppression of JA-regulated defenses depends on the SA-signaling pathway. Applying bacteria isolated from larval oral secretions to wounded plants confirmed that three microbial symbionts belonging to the genera Stenotrophomonas, Pseudomonas, and Enterobacter are responsible for defense suppression. Additionally, reinoculation of these bacteria to antibiotic-treated larvae restored their ability to suppress defenses. Flagellin isolated from Pseudomonas sp. was associated with defense suppression. Our findings show that the herbivore exploits symbiotic bacteria as a decoy to deceive plants into incorrectly perceiving the threat as microbial. By interfering with the normal perception of herbivory, beetles can evade antiherbivore defenses of its host. PMID:24019469

  2. Specificity of induced resistance in tomato against specialist lepidopteran and coleopteran species.

    PubMed

    Chung, Seung Ho; Felton, Gary W

    2011-04-01

    When challenged by herbivorous insects, plants produce a suite of antinutritive proteins that disrupt digestion and absorption of essential nutrients by the insects. We hypothesized that plants would induce distinct defense responses corresponding to the distinct midgut conditions of different herbivores. We investigated whether or not tomato responds specifically to two specialist herbivores: Colorado potato beetle (CPB; Leptinotarsa decemlineata; Coleoptera: Chrysomelidae) and tobacco hornworm (THW; Manduca sexta; Lepidoptera: Sphingidae), and we evaluated whether the induced defenses triggered by either species affect CPB growth. Tomato did not induce different defense genes in response to CPB or THW but accumulated more transcripts for some defense genes after damage by THW feeding compared to damage by CPB feeding. In addition, trypsin protease inhibitor activity and polyphenol oxidase activity were higher in plants damaged by THW than in plants damaged by CPB. Application of oral secretions from THW to wounded tomato plants increased transcripts compared to controls, but oral secretions from CPB decreased defense transcripts. CPB growth was compromised on plants damaged by either species, suggesting a low specificity of effect. Together, these data suggest distinct quantitative responses of tomato to two different specialist herbivores. Herbivore oral secretions might be responsible for these species-specific responses. PMID:21455676

  3. Extraordinary Adaptive Plasticity of Colorado Potato Beetle: "Ten-Striped Spearman" in the Era of Biotechnological Warfare.

    PubMed

    Cingel, Aleksandar; Savić, Jelena; Lazarević, Jelica; Ćosić, Tatjana; Raspor, Martin; Smigocki, Ann; Ninković, Slavica

    2016-01-01

    Expanding from remote areas of Mexico to a worldwide scale, the ten-striped insect, the Colorado potato beetle (CPB, Leptinotarsa decemlineata Say), has risen from being an innocuous beetle to a prominent global pest. A diverse life cycle, phenotypic plasticity, adaptation to adverse conditions, and capability to detoxify or tolerate toxins make this insect appear to be virtually "indestructible". With increasing advances in molecular biology, tools of biotechnological warfare were deployed to combat CPB. In the last three decades, genetically modified potato has created a new challenge for the beetle. After reviewing hundreds of scientific papers dealing with CPB control, it became clear that even biotechnological means of control, if used alone, would not defeat the Colorado potato beetle. This control measure once again appears to be provoking the potato beetle to exhibit its remarkable adaptability. Nonetheless, the potential for adaptation to these techniques has increased our knowledge of this pest and thus opened possibilities for devising more sustainable CPB management programs. PMID:27649141

  4. The involvement of clathrin-mediated endocytosis and two Sid-1-like transmembrane proteins in double-stranded RNA uptake in the Colorado potato beetle midgut.

    PubMed

    Cappelle, K; de Oliveira, C F R; Van Eynde, B; Christiaens, O; Smagghe, G

    2016-06-01

    RNA interference (RNAi) is a powerful tool in entomology and shows promise as a crop protection strategy, but variability in its efficiency across different insect species limits its applicability. For oral uptake of the double-stranded RNA (dsRNA), the RNAi trigger, two different mechanisms are known: systemic RNA interference deficient-1 (Sid-1) transmembrane channel-mediated uptake and clathrin-mediated endocytosis. So far, a wide range of experiments has been conducted, confirming the involvement of one of the pathways in dsRNA uptake, but never both pathways in the same species. We investigated the role of both pathways in dsRNA uptake in the Colorado potato beetle, Leptinotarsa decemlineata, known to have an efficient RNAi response. Through RNAi-of-RNAi experiments, we demonstrated the contribution of two different sid-1-like (sil) genes, silA and silC, and clathrin heavy chain and the 16kDa subunit of the vacuolar H(+) ATPase (vha16), elements of the endocytic pathway, to the RNAi response. Furthermore, the sid-1-like genes were examined through phylogenetic and hydrophobicity analysis. This article reports for the first time on the involvement of two pathways in dsRNA uptake in an insect species and stresses the importance of evaluating both pathways through a well-devised reporter system in any future experiments on cellular dsRNA uptake.

  5. Herbivory responsive C2H2 zinc finger transcription factor protein StZFP2 from potato.

    PubMed

    Lawrence, Susan D; Novak, Nicole G; Jones, Richard W; Farrar, Robert R; Blackburn, Michael B

    2014-07-01

    While C2H2 zinc finger transcription factors (TF) are often regulated by abiotic stress, their role during insect infestation has been overlooked. This study demonstrates that the transcripts of the zinc finger transcription factors StZFP1 and StZFP2 are induced in potato (Solanum tuberosum L.) upon infestation by either the generalist tobacco hornworm (THW, Manduca sexta L.) or the specialist Colorado potato beetle (CPB, Leptinotarsa decemlineata Say). StZFP1 has been previously characterized as conferring salt tolerance to transgenic tobacco and its transcript is induced by Phytophthora infestans and several abiotic stresses. StZFP2 has not been characterized previously, but contains the hallmarks of a C2H2 zinc finger TF, with two conserved zinc finger domains and DLN motif, which encodes a transcriptional repressor domain. Expression studies demonstrate that StZFP2 transcript is also induced by tobacco hornworm and Colorado potato beetle. These observations expand the role of the C2H2 transcription factor in potato to include the response to chewing insect pests.

  6. Changes in digestive rate of a predatory beetle over its larval stage: implications for dietary breadth.

    PubMed

    Lundgren, Jonathan G; Weber, Donald C

    2010-04-01

    Prey and non-prey foods differ substantially in their suitability for zoophytophagous omnivores, but the relative quality of these foods depends on the stage-specific digestive capabilities of the organism in question. Quantitative (or real-time) PCR was used to amplify food-specific DNA and measure consumption rates and digestion efficiencies of four foods - two prey (Aphis glycines and Leptinotarsa decemlineata eggs) and two non-prey (Zea mays pollen and the yeast Saccharomyces cerevisiae) species - over different larval stages of Coleomegilla maculata. The amount of Z. mays pollen consumed increased as larvae aged, but not proportionately with larval size, such that consumption rates decreased uniformly with insect age. While aging larvae fed A. glycines had a similar pattern in their diminishing consumption rates, they consumed similar amounts of A. glycines regardless of age, suggesting a negative feedback mechanism for consumption of this species of aphids. Older larvae digested three of the four foods significantly more efficiently than younger larvae, the exception being larvae fed A. glycines which was digested at a similar rate throughout the larval stage. There was a significant effect of time on food quantity detected for all four species of food. We conclude that C. maculata expands its physiological capacity for digesting prey and non-prey foods as they age in order to better accommodate the increased nutritional needs of the older larvae. This strategy has important implications for the life history strategies of zoophytophagous insects and how they function within foods webs.

  7. Herbivore exploits orally secreted bacteria to suppress plant defenses.

    PubMed

    Chung, Seung Ho; Rosa, Cristina; Scully, Erin D; Peiffer, Michelle; Tooker, John F; Hoover, Kelli; Luthe, Dawn S; Felton, Gary W

    2013-09-24

    Induced plant defenses in response to herbivore attack are modulated by cross-talk between jasmonic acid (JA)- and salicylic acid (SA)-signaling pathways. Oral secretions from some insect herbivores contain effectors that overcome these antiherbivore defenses. Herbivores possess diverse microbes in their digestive systems and these microbial symbionts can modify plant-insect interactions; however, the specific role of herbivore-associated microbes in manipulating plant defenses remains unclear. Here, we demonstrate that Colorado potato beetle (Leptinotarsa decemlineata) larvae exploit bacteria in their oral secretions to suppress antiherbivore defenses in tomato (Solanum lycopersicum). We found that antibiotic-untreated larvae decreased production of JA and JA-responsive antiherbivore defenses, but increased SA accumulation and SA-responsive gene expression. Beetles benefit from down-regulating plant defenses by exhibiting enhanced larval growth. In SA-deficient plants, suppression was not observed, indicating that suppression of JA-regulated defenses depends on the SA-signaling pathway. Applying bacteria isolated from larval oral secretions to wounded plants confirmed that three microbial symbionts belonging to the genera Stenotrophomonas, Pseudomonas, and Enterobacter are responsible for defense suppression. Additionally, reinoculation of these bacteria to antibiotic-treated larvae restored their ability to suppress defenses. Flagellin isolated from Pseudomonas sp. was associated with defense suppression. Our findings show that the herbivore exploits symbiotic bacteria as a decoy to deceive plants into incorrectly perceiving the threat as microbial. By interfering with the normal perception of herbivory, beetles can evade antiherbivore defenses of its host.

  8. New light shed on the oldest insect.

    PubMed

    Engel, Michael S; Grimaldi, David A

    2004-02-12

    Insects are the most diverse lineage of all life in numbers of species, and ecologically they dominate terrestrial ecosystems. However, how and when this immense radiation of animals originated is unclear. Only a few fossils provide insight into the earliest stages of insect evolution, and among them are specimens in chert from Rhynie, Scotland's Old Red Sandstone (Pragian; about 396-407 million years ago), which is only slightly younger than formations harbouring the earliest terrestrial faunas. The most well-known animal from Rhynie is the springtail Rhyniella praecursor (Entognatha; Collembola), long considered to be the oldest hexapod. For true insects (Ectognatha), the oldest records are two apparent wingless insects from later in the Devonian period of North America. Here we show, however, that a fragmentary fossil from Rhynie, Rhyniognatha hirsti, is not only the earliest true insect but may be relatively derived within basal Ectognatha. In fact, Rhyniognatha has derived characters shared with winged insects, suggesting that the origin of wings may have been earlier than previously believed. Regardless, Rhyniognatha indicates that insects originated in the Silurian period and were members of some of the earliest terrestrial faunas.

  9. Resilience in social insect infrastructure systems.

    PubMed

    Middleton, Eliza J T; Latty, Tanya

    2016-03-01

    Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience. PMID:26962030

  10. Resilience in social insect infrastructure systems.

    PubMed

    Middleton, Eliza J T; Latty, Tanya

    2016-03-01

    Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience.

  11. Insect prophenoloxidase: the view beyond immunity

    PubMed Central

    Lu, Anrui; Zhang, Qiaoli; Zhang, Jie; Yang, Bing; Wu, Kai; Xie, Wei; Luan, Yun-Xia; Ling, Erjun

    2014-01-01

    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, β GRP, 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. PMID:25071597

  12. Insect-plant interactions: endocrine defences.

    PubMed

    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.

  13. Resilience in social insect infrastructure systems

    PubMed Central

    2016-01-01

    Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience. PMID:26962030

  14. Evolutionary genetics of insect innate immunity

    PubMed Central

    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 gene family evolution and evolution at the sequence level; both population genetics and molecular evolution frameworks are considered. PMID:25750410

  15. An Automated Flying-Insect Detection System

    NASA Technical Reports Server (NTRS)

    Vann, Timi; Andrews, Jane C.; Howell, Dane; Ryan, Robert

    2007-01-01

    An automated flying-insect detection system (AFIDS) was developed as a proof-of-concept instrument for real-time detection and identification of flying insects. This type of system has use in public health and homeland-security decision support, agriculture and military pest management, and/or entomological research. Insects are first lured into the AFIDS integrated sphere by insect attractants. Once inside the sphere, the insect s wing beats cause alterations in light intensity that is detected by a photoelectric sensor. Following detection, the insects are encouraged (with the use of a small fan) to move out of the sphere and into a designated insect trap where they are held for taxonomic identification or serological testing. The acquired electronic wing-beat signatures are preprocessed (Fourier transformed) in real time to display a periodic signal. These signals are sent to the end user where they are graphically. All AFIDS data are preprocessed in the field with the use of a laptop computer equipped with LabVIEW. The AFIDS software can be programmed to run continuously or at specific time intervals when insects are prevalent. A special DC-restored transimpedance amplifier reduces the contributions of low-frequency background light signals, and affords approximately two orders of magnitude greater AC gain than conventional amplifiers. This greatly increases the signal-to-noise ratio and enables the detection of small changes in light intensity. The AFIDS light source consists of high-intensity Al-GaInP light-emitting diodes (LEDs). The AFIDS circuitry minimizes brightness fluctuations in the LEDs and when integrated with an integrating sphere, creates a diffuse uniform light field. The insect wing beats isotropically scatter the diffuse light in the sphere and create wing-beat signatures that are detected by the sensor. This configuration minimizes variations in signal associated with insect flight orientation. Preliminary data indicate that AFIDS has

  16. Public health advantages of biological insect controls.

    PubMed Central

    Bosch, R

    1976-01-01

    Biological control is not new, it is simply newly appreciated. This renewed appreciation stems from the widespread insecticide treadmill which is largely a product of insecticide disruption of the balance of insect communities. Biological control is a natural phenomenon; the regulation of plant and animal numbers by natural enemies. In this broad sense, biological control is vital to public health because it keeps the myriad insect species from out-competing us. It also has direct public health advantages as where natural enemies are manipulated to control disease vectoring insects. Insecticide distruption of biological control by insecticides and the resulting pesticide treadmill have serious public health implications. One is the increased pesticide load in the environment. The other is the acceleration of pesticide resistance in disease vectoring insects. The treadmill and its associated hazards will not abate so long as chemical control dominates our pest management strategy. PMID:976223

  17. Symbiont-mediated RNA interference in insects.

    PubMed

    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. PMID:26911963

  18. Molecular evolutionary analyses of insect societies

    PubMed Central

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

    2011-01-01

    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. PMID:21690385

  19. Variation in thermal performance among insect populations.

    PubMed

    Sinclair, Brent J; Williams, Caroline M; Terblanche, John S

    2012-01-01

    Among-population variation in insect thermal performance is important for understanding patterns and mechanisms of evolution and predicting insect responses to altered climate regimes in future or novel environments. Here we review and discuss several key examples of among-population variation in insect thermal performance, including latitudinal gradients in chill coma recovery time, variation in energy consumption and metabolic biochemistry, rapid changes in thermal biology with range expansion in invasive and introduced species, and potential constraints on variation in thermal performance traits. This review highlights that while there is substantial evidence for among-population variation that is generally correlated with local climate regimes, neither the underlying mechanisms nor the implications for whole-animal fitness in the field are well understood. We also discuss the potential limitations of interpreting evolved variation among populations and argue for a genes-to-environment approach to population-level variation in thermal biology of insects. PMID:23099457

  20. How to Find Insects Weathering the Winter.

    ERIC Educational Resources Information Center

    Brody, Jane

    1979-01-01

    Discusses how and where to find insects and other invertebrates in winter, as well as how to collect samples in order to watch those animals reappear in spring. Includes crickets, honey bees, mosquitoes, house flies, and butterflies and moths. (MA)

  1. Insect contamination protection for laminar flow surfaces

    NASA Technical Reports Server (NTRS)

    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.

  2. FAQ: Insect Repellent Use and Safety

    MedlinePlus

    ... repellents? Always follow the recommendations appearing on the product label. EPA recommends the following when using insect repellents: ... skin and/or clothing (as directed on the product label). Do not apply repellents under your clothing. Never ...

  3. Encounters with Insects: Field and Classroom Activities.

    ERIC Educational Resources Information Center

    McLure, John W.

    1995-01-01

    Describes field and classroom activities to conduct investigations of insects that emphasize capture and release rather than capture for semipermanent collections. Provides contact information for the Young Entomologists' Society, Inc. (JRH)

  4. Insect food aiming at Mars emigration

    NASA Astrophysics Data System (ADS)

    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.

  5. Molecular evolutionary analyses of insect societies.

    PubMed

    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.

  6. The evolution of color vision in insects.

    PubMed

    Briscoe, A D; Chittka, L

    2001-01-01

    We review the physiological, molecular, and neural mechanisms of insect color vision. Phylogenetic and molecular analyses reveal that the basic bauplan, UV-blue-green-trichromacy, appears to date back to the Devonian ancestor of all pterygote insects. There are variations on this theme, however. These concern the number of color receptor types, their differential expression across the retina, and their fine tuning along the wavelength scale. In a few cases (but not in many others), these differences can be linked to visual ecology. Other insects have virtually identical sets of color receptors despite strong differences in lifestyle. Instead of the adaptionism that has dominated visual ecology in the past, we propose that chance evolutionary processes, history, and constraints should be considered. In addition to phylogenetic analyses designed to explore these factors, we suggest quantifying variance between individuals and populations and using fitness measurements to test the adaptive value of traits identified in insect color vision systems.

  7. Symbiont-mediated RNA interference in insects

    PubMed Central

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

    2016-01-01

    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. PMID:26911963

  8. Principles of Insect Identification. MP-20.

    ERIC Educational Resources Information Center

    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)

  9. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors in the transmission of communicable diseases, through the use of screening, insecticides, and...

  10. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors in the transmission of communicable diseases, through the use of screening, insecticides, and...

  11. Cathepsins of lepidopteran insects: Aspects and prospects.

    PubMed

    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.

  12. Mechanics and aerodynamics of insect flight control.

    PubMed

    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

  13. DDT, pyrethrins, pyrethroids and insect sodium channels.

    PubMed

    Davies, T G E; Field, L M; Usherwood, P N R; Williamson, M S

    2007-03-01

    The long term use of many insecticides is continually threatened by the ability of insects to evolve resistance mechanisms that render the chemicals ineffective. Such resistance poses a serious threat to insect pest control both in the UK and worldwide. Resistance may result from either an increase in the ability of the insect to detoxify the insecticide or by changes in the target protein with which the insecticide interacts. DDT, the pyrethrins and the synthetic pyrethroids (the latter currently accounting for around 17% of the world insecticide market), act on the voltage-gated sodium channel proteins found in insect nerve cell membranes. The correct functioning of these channels is essential for normal transmission of nerve impulses and this process is disrupted by binding of the insecticides, leading to paralysis and eventual death. Some insect pest populations have evolved modifications of the sodium channel protein which prevent the binding of the insecticide and result in the insect developing resistance. Here we review some of the work (done at Rothamsted Research and elsewhere) that has led to the identification of specific residues on the sodium channel that may constitute the DDT and pyrethroid binding sites.

  14. Insect Pathogenic Fungi as Endophytes.

    PubMed

    Moonjely, S; Barelli, L; Bidochka, M J

    2016-01-01

    In this chapter, we explore some of the evolutionary, ecological, molecular genetics, and applied aspects of a subset of insect pathogenic fungi that also have a lifestyle as endophytes and we term endophytic insect pathogenic fungi (EIPF). We focus particularly on Metarhizium spp. and Beauveria bassiana as EIPF. The discussion of the evolution of EIPF challenges a view that these fungi were first and foremost insect pathogens that eventually evolved to colonize plants. Phylogenetic evidence shows that the lineages of EIPF are most closely related to grass endophytes that diverged c. 100MYA. We discuss the relationship between genes involved in "insect pathogenesis" and those involved in "endophytism" and provide examples of genes with potential importance in lifestyle transitions toward insect pathogenicity. That is, some genes for insect pathogenesis may have been coopted from genes involved in endophytic colonization. Other genes may be multifunctional and serve in both lifestyle capacities. The interactions of EIPF with their host plants are discussed in some detail. The genetic basis for rhizospheric competence, plant communication, and nutrient exchange is examined and we highlight, with examples, the benefits of EIPF to plants, and the potential reservoir of secondary metabolites hidden within these beneficial symbioses. PMID:27131324

  15. Linking energetics and overwintering in temperate insects.

    PubMed

    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.

  16. Extracellular ice phase transitions in insects.

    PubMed

    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.

  17. Mechanisms by which pesticides affect insect immunity.

    PubMed

    James, R R; Xu, J

    2012-02-01

    The current state of knowledge regarding the effect of pesticides on insect immunity is reviewed here. A basic understanding of these interactions is needed for several reasons, including to improve methods for controlling pest insects in agricultural settings, for controlling insect vectors of human diseases, and for reducing mortality in beneficial insects. Bees are particularly vulnerable to sublethal pesticide exposures because they gather nectar and pollen, concentrating environmental toxins in their nests in the process. Pesticides do have effects on immunity. Organophosphates and some botanicals have been found to impact hemocyte number, differentiation, and thus affect phagocytosis. The phenoloxidase cascade and malanization have also been shown to be affected by several insecticides. Many synthetic insecticides increase oxidative stress, and this could have severe impacts on the production of some antimicrobial peptides in insects, but research is needed to determine the actual effects. Pesticides can also affect grooming behaviors, rendering insects more susceptible to disease. Despite laboratory data documenting pesticide/pathogen interactions, little field data is available at the population level.

  18. The evolution of plant-insect mutualisms.

    PubMed

    Bronstein, Judith L; Alarcón, Ruben; Geber, Monica

    2006-01-01

    Mutualisms (cooperative interactions between species) have had a central role in the generation and maintenance of life on earth. Insects and plants are involved in diverse forms of mutualism. Here we review evolutionary features of three prominent insect-plant mutualisms: pollination, protection and seed dispersal. We focus on addressing five central phenomena: evolutionary origins and maintenance of mutualism; the evolution of mutualistic traits; the evolution of specialization and generalization; coevolutionary processes; and the existence of cheating. Several features uniting very diverse insect-plant mutualisms are identified and their evolutionary implications are discussed: the involvement of one mobile and one sedentary partner; natural selection on plant rewards; the existence of a continuum from specialization to generalization; and the ubiquity of cheating, particularly on the part of insects. Plant-insect mutualisms have apparently both arisen and been lost repeatedly. Many adaptive hypotheses have been proposed to explain these transitions, and it is unlikely that any one of them dominates across interactions differing so widely in natural history. Evolutionary theory has a potentially important, but as yet largely unfilled, role to play in explaining the origins, maintenance, breakdown and evolution of insect-plant mutualisms.

  19. Factors affecting the sticking of insects on modified aircraft wings

    NASA Technical Reports Server (NTRS)

    Yi, O.; Chan, R.; Eiss, N. S.; Pingali, U.; Wightman, J. P.

    1988-01-01

    The adhesion of insects to aircraft wings is studied. Insects were collected in road tests in past studies and a large experimental error was introduced caused by the variability of insect flux. The presence of such errors has been detected by studying the insect distribution across an aluminum-strip covered half-cylinder mounted on the top of a car. After a nonuniform insect distribution (insect flux) was found from three road tests, a new arrangement of samples was developed. The feasibility of coating aircraft wing surfaces with polymers to reduce the number of insects sticking onto the surfaces was studied using fluorocarbon elastomers, styrene butadiene rubbers, and Teflon.

  20. Colorado potato beetles compensate for tomato cathepsin D inhibitor expressed in transgenic potato.

    PubMed

    Brunelle, France; Cloutier, Conrad; Michaud, Dominique

    2004-03-01

    We reported earlier the importance of digestive cathepsin D-like activity for initiating dietary protein hydrolysis in Colorado potato beetle, Leptinotarsa decemlineata Say [Brunelle et al. (1999) Arch. Insect Biochem. Physiol. 42:88-98]. We assessed here whether transgenic lines of potato (Solanum tuberosum L.) expressing a cathepsin D inhibitor (CDI) from tomato would show resistance to the beetle, or if the insect would compensate for the loss of cathepsin D activity after ingesting the recombinant inhibitor. Transgenic potato lines expressing tomato CDI were developed by Agrobacterium tumefaciens genetic transformation, and selected based on their relative amount of CDI. After confirming the absence of detectable visible effects of CDI on the plant's phenotype, diet assays with control and transgenic lines were carried out to assess the impact of the inhibitor on growth and development of the insect. Leaf consumption, relative growth rate, molting incidence, and digestive protease activity were monitored at 12-h intervals over 132 h for 3rd-instar larvae provided with transgenic potato foliage. Leaf consumption and relative growth rate were slightly reduced during the first 12 h for larvae fed CDI, but no significant differences were observed thereafter. In contrast, time for molting to the 4th larval stage was significantly longer for larvae fed modified plants, with developmental delays of approximately 10 h (0.5 day) compared to control larvae. Recombinant CDI also had an impact on the insect's digestive physiology, readily inducing overproduction of digestive proteases (rubiscases), followed by a gradual decrease of total and pepstatin-sensitive activity. Overall, these observations show the ability of Colorado potato beetle to compensate for the loss of cathepsin D activity by modulating its digestive protease complement in response to aspartate-type inhibitors in the diet. From a practical viewpoint, these data stress the importance of devising improved

  1. Quantifying the movement of multiple insects using an optical insect counter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An optical insect counter (OIC) was designed and tested. The new system integrated a line-scan camera and a vertical light sheet along with data collection and image processing software to count numbers of flying insects crossing a vertical plane defined by the light sheet. The system also allows ...

  2. Naturally occurring insect growth regulators. II. Screening of insect and plant extracts as insect juvenile hormone mimics.

    PubMed

    Jacobson, M; Redfern, R E; Mills, G D

    1975-01-01

    Ethereal extracts prepared from the larvae, pupae, or eggs of 10 species of insects and from various parts of 343 species of higher plants were screened for juvenilizing effects against Tenebrio molitor and Oncopeltus fasciatus. Activity in both species was shown by an extract of the larvae of the stable fly, Stomoxys calcitrans, whereas an extract of the pupae was active in O. fasiatus only. Extracts of two plant species (Echinacea angustifolia roots and Chamaecyparis lawsoniana seeds) showed high juvenilizing activity in T. MOLITOR, AND EXtracts of five plant species (Clethra alnifolia stems, leaves, and fruits, Sassafras albidum roots and root bark, Eucalyptus camaldulensis stems and bark, Pinus rigida twigs and leaves, and Iris douglasiana roots, stems, and fruits) were highly active in O. fasciatus an extract of Tsuga canadensis leaves showed lower activity in this insect. Extracts of 16 species of plants showed high insecticidal activity (mortality) in O. fasciatus but lacked juvenilizing properties in both species of test insects.

  3. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    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. PMID:27030773

  4. Coevolution of parasitic fungi and insect hosts.

    PubMed

    Joop, Gerrit; Vilcinskas, Andreas

    2016-08-01

    Parasitic fungi and their insect hosts provide an intriguing model system for dissecting the complex co-evolutionary processes, which result in Red Queen dynamics. To explore the genetic basis behind host-parasite coevolution we chose two parasitic fungi (Beauveria bassiana and Metarhizium anisopliae, representing the most important entomopathogenic fungi used in the biological control of pest or vector insects) and two established insect model hosts (the greater wax moth Galleria mellonella and the red flour beetle Tribolium castaneum) for which sequenced genomes or comprehensive transcriptomes are available. Focusing on these model organisms, we review the knowledge about the interactions between fungal molecules operating as virulence factors and insect host-derived defense molecules mediating antifungal immunity. Particularly the study of the intimate interactions between fungal proteinases and corresponding host-derived proteinase inhibitors elucidated novel coevolutionary mechanisms such as functional shifts or diversification of involved effector molecules. Complementarily, we compared the outcome of coevolution experiments using the parasitic fungus B. bassiana and two different insect hosts which were initially either susceptible (Galleria mellonella) or resistant (Tribolium castaneum). Taking a snapshot of host-parasite coevolution, we show that parasitic fungi can overcome host barriers such as external antimicrobial secretions just as hosts can build new barriers, both within a relatively short time of coevolution. PMID:27448694

  5. Acoustic communication in insect disease vectors

    PubMed Central

    Vigoder, Felipe de Mello; Ritchie, Michael Gordon; Gibson, Gabriella; Peixoto, Alexandre Afranio

    2013-01-01

    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. PMID:24473800

  6. Insect pest management in forest ecosystems

    NASA Astrophysics Data System (ADS)

    Dahlsten, Donald L.; Rowney, David L.

    1983-01-01

    Understanding the role of insects in forest ecosystems is vital to the development of environmentally and economically sound pest management strategies in forestry Most of the research on forest insects has been confined to phytophagous species associated with economically important tree species The roles of most other insects in forest environments have generally been ignored, including the natural enemies and associates of phytophagous species identified as being important In the past few years several investigations have begun to reevaluate the role of phytophagous species responsible for perturbation in forest ecosystems, and it appears that these species may be playing an important role in the primary productivity of those ecosystems Also, there is an increasing awareness that forest pest managers have been treating the symptoms and not the causes of the problems in the forest Many insect problems are associated with poor sites or sites where trees are growing poorly because of crowding As a result, there is considerable emphasis on the hazard rating of stands of trees for their susceptibility to various phytophagous insects The next step is to manipulate forest stands to make them less susceptible to forest pest complexes A thinning study in California is used as an example and shows that tree mortality in ponderosa pine ( Pinus ponderosa) attributable to the western pine beetle ( Dendroctonus brevicomis) can be reduced by commercial thinning to reduce stocking

  7. Fungus-insect gall of Phlebopus portentosus.

    PubMed

    Zhang, Chun-Xia; He, Ming-Xia; Cao, Yang; Liu, Jing; Gao, Feng; Wang, Wen-Bing; Ji, Kai-Ping; Shao, Shi-Cheng; Wang, Yun

    2015-01-01

    Phlebopus portentosus is a popular edible wild mushroom found in the tropical Yunnan, China, and northern Thailand. In its natural habitats, a gall often has been found on some plant roots, around which fungal fruiting bodies are produced. The galls are different from common insect galls in that their cavity walls are not made from plant tissue but rather from the hyphae of P. portentosus. Therefore we have termed this phenomenon "fungus-insect gall". Thus far six root mealy bug species in the family Pseudococcidae that form fungus-insect galls with P. portentosus have been identified: Formicococcus polysperes, Geococcus satellitum, Planococcus minor, Pseudococcus cryptus, Paraputo banzigeri and Rastrococcus invadens. Fungus-insect galls were found on the roots of more than 21 plant species, including Delonix regia, Citrus maxima, Coffea arabica and Artocarpus heterophyllus. Greenhouse inoculation trials showed that fungus-insect galls were found on the roots of A. heterophyllus 1 mo after inoculation. The galls were subglobose to globose, fulvous when young and became dark brown at maturation. Each gall harbored one or more mealy bugs and had a chimney-like vent for ventilation and access to the gall. The cavity wall had three layers. Various shaped mealy bug wax deposits were found inside the wall. Fungal hyphae invaded the epidermis of plant roots and sometimes even the cortical cells during the late stage of gall development. The identity of the fungus inside the cavity was confirmed by molecular methods. PMID:25344264

  8. Uncontrolled Stability in Freely Flying Insects

    NASA Astrophysics Data System (ADS)

    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.

  9. Magnetoreception in eusocial insects: an update

    PubMed Central

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

    2010-01-01

    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. PMID:20106876

  10. Veins improve fracture toughness of insect wings.

    PubMed

    Dirks, Jan-Henning; Taylor, David

    2012-01-01

    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.

  11. Magnetoreception in eusocial insects: an update.

    PubMed

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

    2010-04-01

    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.

  12. Fungus-insect gall of Phlebopus portentosus.

    PubMed

    Zhang, Chun-Xia; He, Ming-Xia; Cao, Yang; Liu, Jing; Gao, Feng; Wang, Wen-Bing; Ji, Kai-Ping; Shao, Shi-Cheng; Wang, Yun

    2015-01-01

    Phlebopus portentosus is a popular edible wild mushroom found in the tropical Yunnan, China, and northern Thailand. In its natural habitats, a gall often has been found on some plant roots, around which fungal fruiting bodies are produced. The galls are different from common insect galls in that their cavity walls are not made from plant tissue but rather from the hyphae of P. portentosus. Therefore we have termed this phenomenon "fungus-insect gall". Thus far six root mealy bug species in the family Pseudococcidae that form fungus-insect galls with P. portentosus have been identified: Formicococcus polysperes, Geococcus satellitum, Planococcus minor, Pseudococcus cryptus, Paraputo banzigeri and Rastrococcus invadens. Fungus-insect galls were found on the roots of more than 21 plant species, including Delonix regia, Citrus maxima, Coffea arabica and Artocarpus heterophyllus. Greenhouse inoculation trials showed that fungus-insect galls were found on the roots of A. heterophyllus 1 mo after inoculation. The galls were subglobose to globose, fulvous when young and became dark brown at maturation. Each gall harbored one or more mealy bugs and had a chimney-like vent for ventilation and access to the gall. The cavity wall had three layers. Various shaped mealy bug wax deposits were found inside the wall. Fungal hyphae invaded the epidermis of plant roots and sometimes even the cortical cells during the late stage of gall development. The identity of the fungus inside the cavity was confirmed by molecular methods.

  13. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    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.

  14. Insect cell culture in reagent bottles

    PubMed Central

    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. PMID:26150948

  15. Insect societies and the social brain.

    PubMed

    Farris, Sarah M

    2016-06-01

    The 'social brain hypothesis,' the relationship between social behavior and brain size, does not apply to insects. In social insects, especially those of the Order Hymenoptera (ants, bees and wasps), sociality has not always increased individual behavioral repertoires and is associated with only subtle variation in the size of a higher brain center, the mushroom bodies. Rather than sociality, selection for novel visual behavior, perhaps spatial learning, has led to the acquisition of novel visual inputs and profound increases in mushroom body size. This occurred in nonsocial ancestors suggesting that the sensory and cognitive advantages of large mushroom bodies may be preadaptations to sociality. Adaptations of the insect mushroom bodies are more reliably associated with sensory ecology than social behavior. PMID:27436726

  16. Unraveling navigational strategies in migratory insects

    PubMed Central

    Merlin, Christine; Heinze, Stanley; Reppert, Steven M.

    2011-01-01

    Long-distance migration is a strategy some animals use to survive a seasonally changing environment. To reach favorable grounds, migratory animals have evolved sophisticated navigational mechanisms that rely on a map and compasses. In migratory insects, the existence of a map sense (sense of position) remains poorly understood, but recent work has provided new insights into the mechanisms some compasses use for maintaining a constant bearing during long-distance navigation. The best-studied directional strategy relies on a time-compensated sun compass, used by diurnal insects, for which neural circuits have begun to be delineated. Yet, a growing body of evidence suggests that migratory insects may also rely on other compasses that use night sky cues or the Earth's magnetic field. Those mechanisms are ripe for exploration. PMID:22154565

  17. Agricultural applications of insect ecological genomics.

    PubMed

    Poelchau, Monica F; Coates, Brad S; Childers, Christopher P; Peréz de León, Adalberto A; Evans, Jay D; Hackett, Kevin; Shoemaker, DeWayne

    2016-02-01

    Agricultural entomology is poised to benefit from the application of ecological genomics, particularly the fields of biofuels generation and pest control. Metagenomic methods can characterize microbial communities of termites, wood-boring beetles and livestock pests, and transcriptomic approaches reveal molecular bases behind wood-digesting capabilities of these insects, leading to potential mechanisms for biofuel generation. Genome sequences are being exploited to develop new pest control methods, identify candidate antigens to vaccinate livestock, and discover RNAi target sequences and potential non-target effects in other insects. Gene content analyses of pest genome sequences and their endosymbionts suggest metabolic interdependencies between organisms, exposing potential gene targets for insect control. Finally, genome-wide association studies and genotyping by high-throughput sequencing promise to improve management of pesticide resistance. PMID:27436554

  18. Evolutionary interaction networks of insect pathogenic fungi.

    PubMed

    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.

  19. Agricultural applications of insect ecological genomics.

    PubMed

    Poelchau, Monica F; Coates, Brad S; Childers, Christopher P; Peréz de León, Adalberto A; Evans, Jay D; Hackett, Kevin; Shoemaker, DeWayne

    2016-02-01

    Agricultural entomology is poised to benefit from the application of ecological genomics, particularly the fields of biofuels generation and pest control. Metagenomic methods can characterize microbial communities of termites, wood-boring beetles and livestock pests, and transcriptomic approaches reveal molecular bases behind wood-digesting capabilities of these insects, leading to potential mechanisms for biofuel generation. Genome sequences are being exploited to develop new pest control methods, identify candidate antigens to vaccinate livestock, and discover RNAi target sequences and potential non-target effects in other insects. Gene content analyses of pest genome sequences and their endosymbionts suggest metabolic interdependencies between organisms, exposing potential gene targets for insect control. Finally, genome-wide association studies and genotyping by high-throughput sequencing promise to improve management of pesticide resistance.

  20. Soluble proteins in insect chemical communication.

    PubMed

    Pelosi, P; Zhou, J-J; Ban, L P; Calvello, M

    2006-07-01

    Our understanding of the biochemical mechanisms that mediate chemoreception in insects has been greatly improved after the discovery of olfactory and taste receptor proteins. However, the presence of soluble polypeptides in high concentration around the dendrites of sensory neurons still poses unanswered questions. More than 2 decades after their discovery and despite the wealth of structural information available, the physiological function of odorant-binding proteins is not well understood. More recently, members of a second family of soluble polypeptides, the chemosensory proteins, were also discovered in the lymph of chemosensilla. Here we review the structural properties of both classes of soluble proteins, their affinity to small ligands, and their expression in the different parts of the insect body and subcellular localisation. Finally, we discuss current ideas and models of the role of such proteins in insect chemoreception.

  1. Antimicrobial defense and persistent infection in insects.

    PubMed

    Haine, Eleanor R; Moret, Yannick; Siva-Jothy, Michael T; Rolff, Jens

    2008-11-21

    During 400 million years of existence, insects have rarely succumbed to the evolution of microbial resistance against their potent antimicrobial immune defenses. We found that microbial clearance after infection is extremely fast and that induced antimicrobial activity starts to increase only when most of the bacteria (99.5%) have been removed. Our experiments showed that those bacteria that survived exposure to the insect's constitutive immune response were subsequently more resistant to it. These results imply that induced antimicrobial compounds function primarily to protect the insect against the bacteria that persist within their body, rather than to clear microbial infections. These findings suggest that understanding of the management of antimicrobial peptides in natural systems might inform medical treatment strategies that avoid the risk of drug resistance. PMID:19023083

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

    PubMed

    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. PMID:25987228

  3. Remote detection of insect epidemics in conifers

    NASA Technical Reports Server (NTRS)

    Heller, R. C.

    1970-01-01

    With properly exposed color or infrared color film, discolored foliage caused by insect infestations in ponderosa pine is detectable on moderately small-scale photographs with acceptable accuracies. Black and white photographs which matched the wavebands of the ERTS multispectral scanner were combined into one additive color photo. This imagery was not as useful as photographs taken on color, color infrared, or color film with a minus blue filter. Based on the high-altitude color and color infrared photos obtained, it is concluded that only insect infestations larger than 100 meters in diameter are detectable on ERTS imagery.

  4. Insect vision as model for machine vision

    NASA Astrophysics Data System (ADS)

    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.

  5. Two Dimensional Mechanism for Insect Hovering

    SciTech Connect

    Jane Wang, Z.

    2000-09-04

    Resolved computation of two dimensional insect hovering shows for the first time that a two dimensional hovering motion can generate enough lift to support a typical insect weight. The computation reveals a two dimensional mechanism of creating a downward dipole jet of counterrotating vortices, which are formed from leading and trailing edge vortices. The vortex dynamics further elucidates the role of the phase relation between the wing translation and rotation in lift generation and explains why the instantaneous forces can reach a periodic state after only a few strokes. The model predicts the lower limits in Reynolds number and amplitude above which the averaged forces are sufficient. (c) 2000 The American Physical Society.

  6. Pymetrozine causes a nontarget pest, the Colorado potato beetle (Coleoptera: Chrysomelidae), to leave potato plants.

    PubMed

    Chang, G C; Snyder, W E

    2008-02-01

    Pymetrozine is a selective insecticide that targets aphids. Published assessments of the effects of pymetrozine on nontarget organisms focus mainly on predatory insects, and they rarely indicate toxicity. In a laboratory bioassay, survival of Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), larvae was not affected by pymetrozine exposure. We subsequently used pymetrozine to implement low-aphid-density treatments in a field experiment that involved separate manipulations of Colorado potato beetle density. Unexpectedly, the addition of Colorado potato beetle adults and eggs did not increase the densities of Colorado potato beetle larvae in plots that were sprayed with pymetrozine (applied with water and an adjuvant). In control plots sprayed with water and adjuvant (without pymetrozine), addition of Colorado potato beetles increased densities of their larvae. Data collected on a smaller scale suggest that a behavioral mechanism underlies the population-level pattern: Colorado potato beetle larvae become more active and are less likely to remain on a host plant after exposure to pymetrozine. Thus, potato, Solanum tuberosum L., growers who use pymetrozine against aphids also might benefit in terms of Colorado potato beetle control.

  7. Insecticide resistance status of Colorado potato beetle (Coleoptera: Chrysomelidae) adults in northern Xinjiang Uygur autonomous region.

    PubMed

    Jiang, Wei-Hua; Wang, Zhi-Tian; Xiong, Man-Hui; Lu, Wei-Ping; Liu, Ping; Guo, Wen-Chao; Li, Guo-Qing

    2010-08-01

    Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), has become the economically most important insect defoliator of potatoes, Solanum tuberosum L., in northern Xinjiang Uygur autonomous region in China. Currently, control of Colorado potato beetle relies mainly on chemical insecticides. And this may result in insecticide resistance. In this study, LD50 values were measured by a topical bioassay for 14 conventional insecticides in seven local populations from Urumqi, Changji, Tacheng, Nilka, Gongliu, Qapqal, and Tekes counties (cities). The Tekes field population was the most susceptible population and was selected as a reference strain. Compared with the Tekes strain, the Changji, Qapqal, Nilka, Tacheng, and Gongliu populations exhibited moderate to very high levels of resistance to cyhalothrin. The Qapqal and Changji populations showed a moderate and a very high resistance to deltamethrin, respectively. And the Changji population developed a high resistance against alpha-cypermethrin. Moreover, the Qapqal population had a moderate resistance to carbofuran, and the Urumqi population reached high level of resistance to endosulfan. Possible resistance mechanisms of the Changji and Qapqal populations were determined using three enzyme inhibitors. Triphenyl phosphate (TPP), diethylmeleate, and piperonyl butoxide (PBO) had little synergism to cyhalothrin in the two populations. In contrast, PBO and TPP exhibited some synergistic effects to carbofuran in the Qapqal population, indicating the involvement of monooxygenases and esterases in conferring carbofuran resistance. It seems that additional mechanisms, such as target site insensitivity, should play an important role in Colorado potato beetle resistances to cyhalothrin and carbofuran in northern Xinjiang local populations.

  8. Host plant choice experiments of Colorado potato beetle (Coleoptera: Chrysomelidae) in Virginia.

    PubMed

    Hitchner, Erin M; Kuhar, Thomas P; Dickens, Joseph C; Youngman, Roger R; Schultz, Peter B; Pfeiffer, Douglas G

    2008-06-01

    Field and laboratory-choice experiments were conducted to understand aspects of host plant orientation by the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), in Virginia. In laboratory bioassays, L. decemlineata oriented to volatiles emitted by potato, Solanum tuberosum L., foliage over both tomato, Lycopersicon esculentum L., and eggplant, Solanum melongena L., foliage, and eggplant over tomato foliage, all of which had been mechanically damaged. Field choice tests revealed more L. decemlineata adults, larvae, and egg masses on eggplant than on tomato. In other experiments, counts of live L. decemlineata on untreated paired plants and counts of dead beetles on imidacloprid-treated plants did not differ between potato and eggplant. L. decemlineata was significantly attracted to eggplant over both tomato and pepper. To determine whether feeding adults affected orientation to host plants, an imidacloprid-treated eggplant or potato plant was paired with an untreated eggplant or potato plant covered in a mesh bag containing two adult male beetles. Significantly more adults were attracted to eggplant with feeding male beetles paired with another eggplant than any other treatment combination. These results indicate that the presence of male L. decemlineata on plants affects host plant orientation and suggests that the male-produced aggregation pheromone may be involved.

  9. Machine learning for characterization of insect vector feeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects that feed by ingesting plant and animal fluids cause devastating damage to humans, livestock, and agriculture worldwide, primarily by transmitting phytopathogenic and zoonotic pathogens. The feeding processes required for successful disease transmission by sucking insects can be recorded by ...

  10. Molecular mechanisms of phenotypic plasticity in social insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

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

    PubMed

    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.

  12. From Fossil Parasitoids to Vectors: Insects as Parasites and Hosts.

    PubMed

    Nagler, Christina; Haug, Joachim T

    2015-01-01

    Within Metazoa, it has been proposed that as many as two-thirds of all species are parasitic. This propensity towards parasitism is also reflected within insects, where several lineages independently evolved a parasitic lifestyle. Parasitic behaviour ranges from parasitic habits in the strict sense, but also includes parasitoid, phoretic or kleptoparasitic behaviour. Numerous insects are also the host for other parasitic insects or metazoans. Insects can also serve as vectors for numerous metazoan, protistan, bacterial and viral diseases. The fossil record can report this behaviour with direct (parasite associated with its host) or indirect evidence (insect with parasitic larva, isolated parasitic insect, pathological changes of host). The high abundance of parasitism in the fossil record of insects can reveal important aspects of parasitic lifestyles in various evolutionary lineages. For a comprehensive view on fossil parasitic insects, we discuss here different aspects, including phylogenetic systematics, functional morphology and a direct comparison of fossil and extant species.

  13. Hormones and pheromones in regulation of insect behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  14. Insect Biodiversity in the Palearctic Region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect biodiversity in the Palearctic Region is described. Palearctic occupies cold, temperate, and subtropical regions of Eurasia and Africa north of the Sahara Desert together with islands of the Arctic, Atlantic and Pacific oceans. Based on currently available data, there are about 200,000 speci...

  15. Prostaglandins and their receptors in insect biology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 gr...

  16. Transgenic plants protected from insect attack

    NASA Astrophysics Data System (ADS)

    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.

  17. Veins Improve Fracture Toughness of Insect Wings

    PubMed Central

    Dirks, Jan-Henning; Taylor, David

    2012-01-01

    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. PMID:22927966

  18. Asymmetric radar echo patterns from insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  19. Insect flight dynamics: Stability and control

    NASA Astrophysics Data System (ADS)

    Sun, Mao

    2014-04-01

    Insects can hover, fly forward, climb, and descend with ease while demonstrating amazing stability, and they can also maneuver in impressive ways as no other organisms can. Is their flight inherently stable? If so, how can they maneuver so well? In recent years, significant progress has been made in revealing the dynamic flight stability and flight control mechanisms of insects and has partially answered these questions. Here the most recent advances in this active area are reviewed. The aim is to provide the background necessary to do research in the area and raise questions that need to be addressed in the future. This review begins with an overview of the flapping kinematics and aerodynamics of insect flight. It is followed by a summary of the governing equations of insect motion and the simplified theoretical models used for analysis of dynamic stability and control. Next, the stability properties of hovering flight and forward flight are scrutinized. Then the flight control properties are explored, dealing in turn with flight stabilization control, steady-state control for changing from hovering to forward flight and from one forward-flight speed to another, and control for maneuvers near hovering. Finally, remarks are given on the state of the art of this research field and speculation is made on its outlook in the near future.

  20. Quantitative Analysis of Radar Returns from Insects

    NASA Technical Reports Server (NTRS)

    Riley, J. R.

    1979-01-01

    When a number of flying insects is low enough to permit their resolution as individual radar targets, quantitative estimates of their aerial density are developed. Accurate measurements of heading distribution using a rotating polarization radar to enhance the wingbeat frequency method of identification are presented.

  1. Insects: Little Things That Run the World

    ERIC Educational Resources Information Center

    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…

  2. Insect Pests of Field Crops. MP-28.

    ERIC Educational Resources Information Center

    Burkhardt, Chris C.

    This document addresses the principles of field crop insect control through biological, mechanical, and chemical processes. Identification, life history, damage, pesticides, pesticide use and environmental considerations are presented for the major pests of corn, alfalfa, beans, small grains, sugar beets, and potatoes. Each section is accompanied…

  3. Asexuality: the insects that stick with it.

    PubMed

    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.

  4. An insect pupal cell with antimicrobial properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-dwelling insects have developed various defense mechanisms to defend against pathogen infection. The pecan weevil, Curculio caryae, spends two to three years in the soil inside an earthen cell. We hypothesized that the cell may possess antimicrobial properties. In a laboratory study, we teste...

  5. Insect-Plant Relationships in Ecological Teaching.

    ERIC Educational Resources Information Center

    Fry, G. L. A.; Wratten, S. D.

    1979-01-01

    Discusses the current theories concerning the evolution of insect-plant relationships. Offers several experiments based on recent publications in this field, concerning relationships between herbivore number and plants' successional status, geographical range, geological history, and stage of growth, and also experiments on the chemical basis of…

  6. Insect Control (II): Hormones and Viruses

    ERIC Educational Resources Information Center

    Marx, Jean L.

    1973-01-01

    Discusses research in the use of hormones and viruses to control insect populations. Although entomologists do not think that pheromones, hormones, and viruses will completely replace more conventional chemical insecticides, they will become increasingly important and will reduce our dependence on traditional insecticides. (JR)

  7. Bug City: House and Backyard Insects [Videotape].

    ERIC Educational Resources Information Center

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography, fun…

  8. Almond Production Manual Chapter: Insects and Mites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The navel orangeworm, Amyelois transitella (Walker), is the most important insect pest of almond in California and can cost as much as $500 dollars per acre to control when the costs of insecticides and sanitation are included. It is a native of the southwestern United States and Mexico and was firs...

  9. Novel proteinase inhibitor promotes resistance to insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  10. Prospects for gene transmformation in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to manipulate genetic material in vitro and integrate it into a host genome has proven to be one of the more powerful methods of genetic analysis, as well as a means to manipUlate an organism's biology. In insects, the use of gene transformation is equally Significant in its potential to...

  11. Studying insect diversity in the tropics.

    PubMed Central

    Godfray, H C; Lewis, T; Memmott, J

    1999-01-01

    Understanding the extent and causes of insect diversity in the humid tropics is one of the major challenges in modern ecology. We review some of the current approaches to this problem, and discuss how future progress may be made. Recent calculations that there may be more than 30 million species of insect on earth have focused attention on the magnitude of this problem and stimulated several new lines of research (although the true figure is now widely thought to be between five and ten million species). We discuss work based on insecticidal logging surveys; studies of herbivore and parasitoid specificity; macroecological approaches; and the construction of food webs. It is argued that progress in estimating insect diversity and in understanding insect community dynamics will be enhanced by building local inventories of species diversity, and in descriptive and experimental studies of the trophic structure of communities. As an illustration of work aimed at the last goal, we discuss the construction and analysis of quantitative host-parasitoid food webs, drawing on our work on leaf miner communities in Central America. PMID:11605624

  12. Development of Baits for Insect Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article outlines the importance of baits. Baits are formulations that can be used to deliver a toxic chemical or a pathogen (active agent) via ingestion to an insect pest with the goal of killing it. A bait formulations consist of a bait matrix which is the carrier for an active agent. The bait...

  13. Coordination ability of insect kinin analogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  14. Insects of war, terror and torture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. A Sequential Insect Dispenser for Behavioral Experiments

    ERIC Educational Resources Information Center

    Gans, Carl; Mix, Harold

    1974-01-01

    Describes the construction and operation of an automatic insect dispenser suitable for feeding small vertebrates that are being maintained for behavioral experiments. The food morsels are squirted from their chambers an an air jet, and may be directed at a particluar portion of the cage or distributed to different areas. (JR)

  16. Magnetoreception in Eusocial Insects: An Update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Behavioral 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 in migratory paths. Bees show sensitivity to small changes in magnetic fields in conditioning experiments a...

  17. Mode of action of insect repellents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  18. Insect Pests Models and Insecticide Application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past, the dominant approach in theoretical pest management ecology has emphasized the use of simple analytical or mathematical models and the analysis of systems in equilibrium. Recent advancements in computer technology have provided the opportunity for ecological insect modelers to move aw...

  19. Recombinant protein production and insect cell culture and process

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn (Inventor); Prewett, Tacey (Inventor); Goodwin, Thomas (Inventor); Francis, Karen (Inventor); Andrews, Angela (Inventor); Oconnor, Kim (Inventor)

    1993-01-01

    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 the cultured insect cells as host for a virus encoding the described polypeptide such as baculovirus. The insect cells can also be a host for viral production.

  20. Recombinant Protein Production and Insect Cell Culture and Process

    NASA Technical Reports Server (NTRS)

    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.

  1. Similarities between decapod and insect neuropeptidomes

    PubMed Central

    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

  2. Similarities between decapod and insect neuropeptidomes.

    PubMed

    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

  3. Similarities between decapod and insect neuropeptidomes.

    PubMed

    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

  4. INSECT PHYLOGENOMICS. Comment on "Phylogenomics resolves the timing and pattern of insect evolution".

    PubMed

    Tong, K Jun; Duchêne, Sebastián; Ho, Simon Y W; Lo, Nathan

    2015-07-31

    Misof et al. (Reports, 7 November 2014, p. 763) used a genome-scale data set to estimate the relationships among insect orders and the time scale of their evolution. Here, we reanalyze their data and show that their method has led to systematic underestimation of the evolutionary time scale. We find that key insect groups evolved up to 100 million years earlier than inferred in their study.

  5. Coconut leaf bioactivity toward generalist maize insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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,...

  6. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 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...

  7. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 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....

  8. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 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...

  9. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 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...

  10. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    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....

  11. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 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....

  12. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 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....

  13. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 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....

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

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 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. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 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....

  16. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 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...

  17. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 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...

  18. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 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....

  19. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 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....

  20. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 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....

  1. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 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...

  2. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 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....

  3. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 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....

  4. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2010 CFR

    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....

  5. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 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....

  6. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 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...

  7. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 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....

  8. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    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....

  9. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 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....

  10. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 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....

  11. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 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....

  12. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 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....

  13. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2010 CFR

    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...

  14. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 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...

  15. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 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...

  16. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2010 CFR

    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...

  17. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 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...

  18. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true 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...

  19. Impact of distinct insect pollinators on gene flow

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vast majority of fruits and vegetables, together with some hay crops (alfalfa) and some oil-producing crops (canola) are pollinated by insects. However we have little information on how insect pollinators affect the movement of genes via pollen and even less on how distinct insect pollinators ma...

  20. Job Grading Standard for Insects Production Worker WG-5031.

    ERIC Educational Resources Information Center

    Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

    The standard is for grading nonsupervisory jobs involved in reproducing, collecting, and caring for insect collections. The work requires practical knowledge of the characteristics of insects and their needs, and skill in observing and handling them. The levels of insects production worker WG-3, WG-4, and WG-5 are differentiated by describing the…