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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 Central

    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. PMID:19221142

  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. Syspastospora parasitica, a mycoparasite of the fungus Beauveria bassiana attacking the Colorado potato beetle Leptinotarsa decemlineata: A tritrophic association.

    PubMed Central

    Posada, Francisco; Vega, Fernando E.; Rehner, Stephen A.; Blackwell, Meredith; Weber, Donald; Suh, Sung-Oui; Humber, Richard A.

    2004-01-01

    A tritrophic association is reported, involving a Colorado potato beetle (Leptinotarsa decemlineata) infected with Beauveria bassiana, which in turn was infected with Syspastospora parasitica. PMID:15861239

  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. PMID:26206894

  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. PMID:26030877

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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

  13. Involvement of FTZ-F1 in the regulation of pupation in Leptinotarsa decemlineata (Say).

    PubMed

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

    2014-11-01

    During the final instar larvae of holometabolous insects, a pulse of 20-hydroxyecdysone (20E) and a drop in juvenile hormone (JH) trigger larval-pupal metamorphosis. In this study, two LdFTZ-F1 cDNAs (LdFTZ-F1-1 and LdFTZ-F1-2) were cloned in Leptinotarsa decemlineata. Both LdFTZ-F1-1 and LdFTZ-F1-2 were highly expressed just before or right after each molt, similar to the expression pattern of an ecdysteroidogenesis gene LdSHD. Ingestion of an ecdysteroid agonist halofenozide (Hal) enhanced LdFTZ-F1-1 and LdFTZ-F1-2 expression in the final larval instar. Conversely, a decrease in 20E by feeding a double-stranded RNA (dsRNA) against LdSHD repressed the expression. Moreover, Hal rescued the expression levels in LdSHD-silenced larvae. Thus, 20E peaks seem to induce the transcription of LdFTZ-F1s. Furthermore, ingesting dsLdFTZ-F1 from a common fragment of LdFTZ-F1-1 and LdFTZ-F1-2 successfully knocked down both LdFTZ-F1s, and impaired pupation. Finally, knocking down LdFTZ-F1s significantly repressed the transcription of three ecdysteroidogenesis genes, lowered 20E titer, and reduced the expression of two 20E receptor genes. Silencing LdFTZ-F1s also induced the expression of a JH biosynthesis gene, increased JH titer, but decreased the mRNA level of a JH early-inducible gene. Thus, LdFTZ-F1s are involved in the regulation of pupation by modulating 20E and JH titers and mediating their signaling pathways. PMID:25446391

  14. 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

  15. 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...

  16. 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...

  17. 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...

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. [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

  10. [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

  11. 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

  12. 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

  13. Behavioural response of Colorado potato beetle (Leptinotarsa decemlineata) larvae to selected plant extracts.

    PubMed

    Gökçe, Ayhan; Isaacs, Rufus; Whalon, Mark E

    2006-11-01

    Potato leaves were treated with 2, 20 or 200 g kg(-1) solutions of extracts of five plant species collected in Turkey, and then exposed to larvae of Colorado potato beetle, Leptinotarsa decemlineata (Say). During the first 24 h of exposure, leaf consumption was not affected by 2 g kg(-1) extracts, whereas significantly more leaf tissue remained on leaves treated with 20 g kg(-1) extracts of Arctium lappa L., Bifora radians M Bieb, Humulus lupulus L. or Xanthium strumarium L. than on untreated control leaves. Feeding was not affected by the 20 g kg(-1) extract of Verbascum songaricum Schrenk ex Fisch & Mey. Extracts of all species at 200 g kg(-1) reduced larval feeding, with H. lupulus and X. strumarium providing the greatest protection. Observations of larval behaviour over the first 15 min of exposure to these extracts revealed that the interaction of beetles with leaf tissue was significantly affected by plant extracts. Feeding frequency was not affected by 2 g kg(-1) extracts but was reduced by all higher concentrations. Feeding was inhibited completely by 20 g kg(-1) of H. lupulus extract and reduced significantly compared with the controls by all other extracts. Suppression of feeding was caused by all extracts at 200 g kg(-1), with V. songaricum providing 91% reduction in feeding duration. Rejection behaviour, in which larvae did not return to the leaf after their interaction with it, was rare on 2 g kg(-1) extracts but seen in over 60% of larvae on 20 g kg(-1) extracts and over 80% on 200 g kg(-1) extracts. The present results demonstrate that these extracts have significant ability to protect potato leaves for up to 24 h by prevention of feeding behaviour by L. decemlineata. Further studies are needed to determine the potential of these plant extracts, or their active components, for use in biologically based pest management strategies. PMID:16886174

  14. 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.

  15. 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

  16. 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

  17. RNA interference suppression of the receptor tyrosine kinase Torso gene impaired pupation and adult emergence in Leptinotarsa decemlineata.

    PubMed

    Zhu, Tao-Tao; Meng, Qing-Wei; Guo, Wen-Chao; Li, Guo-Qing

    2015-12-01

    In Drosophila melanogaster prothoracic gland (PG) cells, Torso mediates prothoracicotropic hormone (PTTH)-triggered mitogen activated protein kinase (MAPK) pathway (consisting of four core components Ras, Raf, MEK and ERK) to stimulate ecdysteroidogenesis. In this study, LdTorso, LdRas, LdRaf and LdERK were cloned in Leptinotarsa decemlineata. The four genes were highly or moderately expressed in the larval prothoracic glands. At the first- to third-instar stages, their expression levels were higher just before and right after the molt, and were lower in the mid instars. At the fourth-instar stage, their transcript levels were higher before prepupal stage. RNA interference-mediated knockdown of LdTorso delayed larval development, increased pupal weight, and impaired pupation and adult emergence. Moreover, knockdown of LdTorso decreased the mRNA levels of LdRas, LdRaf and LdERK, repressed the transcription of two ecdysteroidogenesis genes (LdPHM and LdDIB), lowered 20E titer, and downregulated the expression of several 20E-response genes (LdEcR, LdUSP, LdHR3 and LdFTZ-F1). Furthermore, silencing of LdTorso induced the expression of a JH biosynthesis gene LdJHAMT, increased JH titer, and activated the transcription of a JH early-inducible gene LdKr-h1. Thus, our results suggest that Torso transduces PTTH-triggered MAPK signal to regulate ecdysteroidogenesis in the PGs in a non-drosophiline insect. PMID:26518287

  18. Interactions between population density of the Colorado potato beetle, Leptinotarsa decemlineata, and herbicide rate for suppression of solanaceous weeds.

    PubMed

    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

  19. 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

  20. 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

  1. 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

  2. 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.

  3. [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

  4. Long-term reduction of cold hardiness following ingestion of ice-nucleating bacteria in the Colorado potato beetle, Leptinotarsa decemlineata.

    PubMed

    Costanzo dagger, J P.; Humphreys double dagger, T L.; Lee, R E.; Moore dagger, J B.; Lee double dagger, M R.; Wyman, J A.

    1998-12-01

    We investigated the effect of ingestion of ice-nucleating bacteria on the supercooling capacity and cold hardiness of the Colorado potato beetle (Leptinotarsa decemlineata Say), a freeze-intolerant species that overwinters as adults in shallow, terrestrial burrows. Ingestion of ice-nucleating bacteria (Enterobacter agglomerans, Pseudomonas fluorescens, Pseudomonas putida, Pseudomonas syringae), fed on slices of potato tuber, caused an abrupt decrease in supercooling capacity. No change occurred in the supercooling capacity of beetles fed Escherichia coli, as this species lacks ice-nucleating activity. Ingestion rates showed that tubers treated with different species were equally palatable. During diapause induction beetles evacuated food from their guts, but nevertheless retained sufficient ice-nucleating bacteria to diminish supercooling. Beetles fed P. fluorescens and P. putida exhibited reduced supercooling even after an 8-wk exposure to simulated winter conditions. Furthermore, P. fluorescens was isolated 10-wk post-ingestion from diapausing beetles. Our data suggest that ingested bacteria may be retained by insects during entry into diapause and that the cold hardiness of candidate crop pests, such as L. decemlineata, may be reduced by feeding them ice-nucleating bacteria prior to winter diapause. PMID:12770317

  5. 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

  6. Response of digestive cysteine proteinases from the Colorado potato beetle (Leptinotarsa decemlineata) and the black vine weevil (Otiorynchus sulcatus) to a recombinant form of human stefin A.

    PubMed

    Michaud, D; Nguyen-Quoc, B; Vrain, T C; Fong, D; Yelle, S

    1996-01-01

    The effects of the cystatins, human stefin A (HSA) and oryzacystatin I (OCI) on digestive cysteine proteinases of the Colorado potato beetle (CPB), Leptinotarsa decemlineata, and the black vine weevil (BVW), Otiorynchus sulcatus, were assessed using complementary inhibition assays, cystatin-affinity chromatography, and recombinant forms of the two inhibitors. For both insects, either HSA and OCI used in excess (10 or 20 microM) caused partial and stable inhibition of total proteolytic (azocaseinase) activity, but unlike for OCI the HSA-mediated inhibitions were significantly increased when the inhibitor was used in large excess (100 microM). As demonstrated by complementary inhibition assays, this two-step inhibition of the insect proteases by HSA was due to the differential inactivation of two distinct cysteine proteinase populations in either insect extracts, the rapidly (strongly) inhibited population corresponding to the OCI-sensitive fraction. After removing the cystatin-sensitive proteinases from CPB and BVW midgut extracts using OCI- (or HSA-) affinity chromatography, the effects of the insect "non-target" proteases on the structural integrity of the two cystatins were assessed. While OCI remained essentially stable, HSA was subjected to hydrolysis without the accumulation of detectable stable intermediates, suggesting the presence of multiple exposed cleavage sites sensitive to the action of the insect proteases on this cystatin. This apparent susceptibility of HSA to proteolytic cleavage may partially explain its low efficiency to inactivate the insect OCI-insensitive cysteine proteinases when not used in large excess. It could also have major implications when planning the use of cystatin-expressing transgenic plants for the control of coleopteran pests. PMID:8920105

  7. 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

  8. 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

  9. 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

  10. 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

  11. Hemocyte Responses of the Colorado Potato Beetle, Leptinotarsa decemlineata, and the Greater Wax Moth, Galleria mellonella, to the Entomopathogenic Nematodes, Steinernema feltiae and Heterorhabditis bacteriophora

    PubMed Central

    Ebrahimi, L.; Niknam, G.; Dunphy, G. B.

    2011-01-01

    Hemocyte encapsulation reactions of infective juveniles of two Iranian isolates of the entomopathogenic nematodes, Heterorhabditis bacteriophora Poinar (Rhabditina: Heterorhabditidae) and Steinernema feltiae Filipjev (Tylenchina: Steinernematidae), were compared in the economic pest Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), and the greater wax moth, Galleria mellonella L. (Lepidoptera: Pyralidae). The former was a more responsive host than the latter and the hemocyte responses occurred sooner and more extensively. Complete encapsulation of some of the nematodes occurred by 4 h post injection for H. bacteriophora in both L. decemlineata and G. mellonella, and by 2 h pi for S. feltiae in L. decemlineata. The percentage of encapsulation from 24 h to 72 h pi in L. decemlineata was 86.2% for S. feltiae and 39% for H. bacteriophora. In G. mellonella there were no encapsulation or melanization responses against S. feltiae, whereas when H. bacteriophora was encapsulated and melanized (16.7%) the encapsulation level was lower than in L. decemlineata. This study may contribute to effectively selecting entomopathogenic nematode species active against significant economic pests based on the latter's cellular immune response. PMID:21867441

  12. 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

  13. 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

  14. Sexual contact influences orientation to plant attractant in Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemical signals emitted by insects and their hosts are important for sexual communication and feeding. Plant volatiles facilitate the location of suitable hosts for feeding and oviposition, and may moderate responses to sex and aggregation pheromones. While mating has been shown to moderate behav...

  15. Characterization of cell lines developed from the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae).

    PubMed

    Charpentier, G; Tian, L; Cossette, J; Léry, X; Belloncik, S

    2002-02-01

    In order to isolate new pathogens (viruses, microsporidia, etc.) or to evaluate the efficiency of some pathogens (serovarieties and mutants of Bacillus thuringiensis, fungi, etc.) in the control of Colorado potato beetle, an economically important pest, we established four cell lines from tissues of this insect. One was initiated from embryonated egg fragments in the M3 medium supplemented with 20% fetal bovine serum (FBS) and then transferred after several passages to the Ex-Cell 400 medium with 20% FBS. Another was initiated from larval hemocytes in Ex-Cell 400 with 5% FBS. Finally, two other cell lines were initiated from adult hemocytes: one in the Ex-Cell 400 with 20% FBS and 1% of lipid mixture and the other in the Ex-Cell 400 with 5% FBS only. These cell lines have been characterized by their morphology with light and electron microscopy, their karyotypes, cell growth, and isozyme analysis. Each cell line differed in morphologic, karyologic, growth, and isozyme patterns. The cell line initiated from embryonated eggs was growing slower than the three initiated from hemocytes. The cytotoxicity of solubilized crystal delta-endotoxins from different B. thuringiensis formulations (M-One, Trident, MYX-1806, Teknar-HPD, and Thuricide) and of destruxins, mycotoxins from Metarhizium anisopliae, was tested on these cell lines. They are sensitive to the solubilized toxins of some strains of B. thuringiensis (serovar. San Diego and serovar. tenebrionis) and to destruxins, and they can be used for the bioassay and detection of toxins and for the study of the mechanism of their action on coleopteran cells. PMID:11928998

  16. 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

  17. 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

  18. 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

  19. 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

  20. DIFFERENTIAL GENE EXPRESSION AND RESPIRATION RATES DURING THE PREDIAPAUSE PHASE OF THE COLORADO POTATO BEETLE, LEPTINOTARSA DECEMLINEATA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For an insect species to survive in any given geographic location, its life cycle must be tightly synchronized to all biotic and abiotic factors required for development and reproduction. Insects must also be able to survive predictable recurring periods of environmental stress, such as winter for ...

  1. 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

  2. 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

  3. 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 ...

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

    PubMed Central

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

    2012-01-01

    Summary 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

  5. 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

  6. 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

    2012-01-01

    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

  7. 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

  8. 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

  9. 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

  10. Effectiveness of glues used for harmonic radar tag attachment and impact on survival and behavior of three insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of three cyanoacrylate glues to ensure a durable bond between the Colorado potato beetle, Leptinotarsa decemlineata (Say), the plum curculio, Conotrachelus nenuphar (Herbst) or the Corn Rootworms, (Western Corn Rootworm, Diabrotica virgifera virgifera LeConte and Northern Corn Rootworm, ...

  11. CLONING OF THREE DESICCATION REGULATED TRANSCRIPTS FROM DIAPAUSING COLORADO POTATO BEETLE, LEPTINOTARSA DECEMLINEATA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Clones of three desiccation up-regulated transcripts (LdDes-1, -2 & -3) were isolated from diapausing Colorado potato beetle using suppression subtractive hybridization. Northern blot analysis demonstrated that LdDes-1, -2 & -3 are highly up-regulated in diapausing beetles and in desiccated nondiap...

  12. 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 ...

  13. Examining the molecular interaction between potato (Solanum tuberosum) and Colorado potato beetle Leptinotarsa decemlineata (Say)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Colorado potato beetle (CPB) is a leading pest of solanaceous plants; however, little is known about its molecular interaction with the potato plant. Using the 11,421 EST array solanaceae microarray profiling services at TIGR, we have identified genes that are differentially expressed in potato leav...

  14. 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

  15. 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

  16. 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

  17. 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. PMID:26833679

  18. Two genes become one: the genes encoding heterochromatin protein Su(var)3-9 and translation initiation factor subunit eIF-2gamma are joined to a dicistronic unit in holometabolic insects.

    PubMed Central

    Krauss, V; Reuter, G

    2000-01-01

    The Drosophila suppressor of position-effect variegation Su(var)3-9 encodes a heterochromatin-associated protein that is evolutionarily conserved. In contrast to its yeast and mammalian orthologs, the Drosophila Su(var)3-9 gene is fused with the locus encoding the gamma subunit of translation initiation factor eIF2. Synthesis of the two unrelated proteins is resolved by alternative splicing. A similar dicistronic Su(var)3-9/eIF-2gamma transcription unit was found in Clytus arietis, Leptinotarsa decemlineata, and Scoliopterix libatrix, representing two different orders of holometabolic insects (Coleoptera and Lepidoptera). In all these species the N terminus of the eIF-2gamma, which is encoded by the first two exons, is fused to SU(VAR)3-9. In contrast to Drosophila melanogaster, RT-PCR analysis in the two coleopteran and the lepidopteran species demonstrated the usage of a nonconserved splice donor site located within the 3' end of the SU(VAR)3-9 ORF, resulting in removal of the Su(var)3-9-specific stop codon from the mRNA and complete in-frame fusion of the SU(VAR)3-9 and eIF-2gamma ORFs. In the centipede Lithobius forficatus eIF-2gamma and Su(var)3-9 are unconnected. Conservation of the dicistronic Su(var)3-9/eIF-2gamma transcription unit in the studied insects indicates its origin before radiation of holometabolic insects and represents a useful tool for molecular phylogenetic analysis in arthropods. PMID:11063691

  19. Interactions between population density of the Colorado potato beetle, Leptinotarsa decemlineata, and herbicide rate for suppression of solanaceous weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence of volunteer potatoes Solanum tuberosum L., cutleaf nightshade, S. triflorum N., and hairy nightshade, S. physalifolium Rusby (Solanales: Solanceae), throughout potato crop rotations can diminish the effectiveness of crop rotations designed to control disease and pest problems associate...

  20. 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

  1. 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...

  2. 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...

  3. Integrated use of Beauveria bassiana and Bacillus thuringiensis serovar. tenebrionis for microbial biocontrol of Colorado potato beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reviews the potential for using insect pathogens to control the Colorado potato beetle, Leptinotarsa decemlineata, and summarizes results from nearly 10 years of research by USDA-ARS-PPRU scientists aimed at developing methods and strategies for integrated use of Bacillus thuringiensis an...

  4. Potato defense against Colorado potato beetle Leptinotarsa decemlineata (Say): microarray gene expression profiling of potato (Solanum tuberosum) by Colorado potato beetle infestation and regurgitant treatment of

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Colorado potato beetle is the leading pest of solanaceous plants, however little is known about the interaction of this beetle with the potato plant. Using the 11,421 EST solanaceae microarry profiling services at TIGR we have begun investigating the genes that are differentially expressed by infest...

  5. 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, ...

  6. Isolation and characterization of a novel family (Mild-4) of miniature subterminal inverted repeat transposable element from the Colorado potato beetle, Leptinotarsa decemlineata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Determining the genomic structure of DAT-2 and -3 led to the isolation of four novel families of miniature subterminal inverted repeat transposable 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, has a 14 bp tar...

  7. Host plant preference in Colorado potato beetle (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field and laboratory-choice tests were conducted to better understand host plant preference by the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), in Virginia. In laboratory olfactometer studies, L. decemlineata preferred potato over both tomato and eggplant foli...

  8. 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

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

    PubMed Central

    Piiroinen, Saija; Lyytinen, Anne; Lindström, Leena

    2013-01-01

    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

  10. 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

  11. 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…

  12. 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…

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. 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 ...

  18. 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...

  19. 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,…

  20. 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...

  1. 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)

  2. [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

  3. 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

  4. 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

  5. Insect Bites and Stings

    MedlinePlus

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

  6. 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.

  7. 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 ...

  8. 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)

  9. 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.

  10. 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…

  11. 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,…

  12. Acoustic Monitoring of Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers, grain elevator managers, and food processors often sample grain for insect damaged kernels and numbers of live adult insects but these easily obtained measurements of insect levels do not provide reliable estimates of the typically much larger populations of internally feeding immature inse...

  13. 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...

  14. Interdisciplinary Outdoor Education, Insects.

    ERIC Educational Resources Information Center

    Orsborn, Edward E.

    This manual is a teacher's resource and guide book describing activities for elementary students involving the collecting, killing, preserving, and identification of insects. Most activities relate to collecting and identifying, but activities involving terrariums and hatcheries, finding hidden insects, and insect trapping are also described.…

  15. 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)

  16. InsectBase: a resource for insect genomes and transcriptomes.

    PubMed

    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

  17. 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

  18. Insect Barcode Information System

    PubMed Central

    Pratheepa, Maria; Jalali, Sushil Kumar; Arokiaraj, Robinson Silvester; Venkatesan, Thiruvengadam; Nagesh, Mandadi; Panda, Madhusmita; Pattar, Sharath

    2014-01-01

    Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally important insects. IBIn was developed using PHP/My SQL by using relational database management concept. This database is based on the client– server architecture, where many clients can access data simultaneously. IBIn is freely available on-line and is user-friendly. IBIn allows the registered users to input new information, search and view information related to DNA barcode of agriculturally important insects.This paper provides a current status of insect barcode in India and brief introduction about the database IBIn. Availability http://www.nabg-nbaii.res.in/barcode PMID:24616562

  19. Genetic Nature, Stability, and Improved Virulence of Hybrids from Protoplast Fusion in Beauveria

    PubMed

    Couteaudier; Viaud; Riba

    1996-07-01

    Genetic improvement of two different strains of the entomopathogenic fungus Beauveria bassiana for more effective control of Ostrinia nubilalis and Leptinotarsa decemlineata was obtained by crosses with the insecticidal toxin-producing strain Beauveria sulfurescens. Protoplast fusion between diauxotrophic mutants resulted in the recovery of some stable prototrophic fusion products. The low levels of virulence of the wild type strain B. bassiana 28 isolated originally from L. decemlineata were enhanced both on L. decemlineata and O. nubilalis for one of the hybrids obtained (FP 8) from the cross B. bassiana 28xB. sulfurescens 2. Fusion product 25 obtained from the cross between B. sulfurescens and the highly pathogenic strain B. bassiana 147 showed a three-day reduction in the LT50 towards O. nubilalis. Southern blot hybridization with nine probe-enzyme combinations were conducted on genomic DNAs from the original wild strains, parental mutant strains, and fusion products. Additive banding patterns or unique banding pattern of either parental strain was observed in five hybrids, indicating their status as recombinant and/or partially diploid. Combination of RFLP markers indicative of both parental genomes was never observed with fusion product FP 25. The stability of the virulence following passage through insect-host and stability of molecular structure for the fusion products FP 8 and FP 25 suggest that asexual genetic recombination by protoplast fusion may provide an attractive method for the genetic improvement of biocontrol efficiency in entomopathogenic fungi. PMID:8661542

  20. 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

  1. 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

  2. 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…

  3. 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.…

  4. 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...

  5. 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,...

  6. Effects on Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of controlled and modified atmospheres on insects is reviewed and summarized in this chapter. Traditionally, controlled and modified atmospheres are used to store and preserve fresh fruits and vegetables. The effects on insects and the potential of these treatments are secondary to the...

  7. 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 ...

  8. 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)

  9. Mycetocyte symbiosis in insects.

    PubMed

    Douglas, A E

    1989-11-01

    1. Non-pathogenic microorganisms, known as mycetocyte symbionts, are located in specialized 'mycetocyte' cells of many insects that feed on nutritionally unbalanced or poor diets. The insects include cockroaches, Cimicidae and Lygaeidae (Heteroptera), the Homoptera, Anoplura, the Diptera Pupiparia, some formicine ants and many beetles. 2. Most mycetocyte symbionts are prokaryotes and a great diversity of forms has been described. None has been cultured in vitro and their taxonomic position is obscure. Yeasts have been reported in Cerambycidae and Anobiidae (Coleoptera) and a few planthoppers. They are culturable and those in anobiids have been assigned to the genus Torulopsis. 3. The mycetocyte cells may be associated with the gut, lie free in the abdominal haemocoel or be embedded in the fat body of the insect. The mycetocytes are large polyploid cells which rarely divide and the symbionts are restricted to their cytoplasm. 4. The mycetocyte symbionts are transmitted maternally from one insect generation to the next. In many beetles (Anobiidae, Cerambycidae, Chrysomelidae and cleonine Curculionidae), the microoganisms are smeared onto the eggs and consumed by the hatching larvae. In other insects, they are transferred from mycetocytes to oocytes in the ovary, a process known as transovarial transmission. The details of transmission in the different insect groups vary with the age of the mother (adult, larva or embryo) at which symbiont transfer to the ovary is initiated; whether isolated symbionts or intact mycetocytes are transferred; and the site of entry of symbionts to the egg (anterior, posterior or apolar). 5. Within an individual insect, the biomass of symbionts varies in a regular fashion with age, weight and sex of the insect. Suppression of symbiont growth rate and lysis of 'excess' microorganisms may contribute to the regulation of symbionts (including freshly-isolated preparations of unculturable forms) are used to investigate interactions between the

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  11. 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.

  12. 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

  13. 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...

  14. 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…

  15. 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

  16. 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,…

  17. Insect immunology and hematopoiesis.

    PubMed

    Hillyer, Julián F

    2016-05-01

    Insects combat infection by mounting powerful immune responses that are mediated by hemocytes, the fat body, the midgut, the salivary glands and other tissues. Foreign organisms that have entered the body of an insect are recognized by the immune system when pathogen-associated molecular patterns bind host-derived pattern recognition receptors. This, in turn, activates immune signaling pathways that amplify the immune response, induce the production of factors with antimicrobial activity, and activate effector pathways. Among the immune signaling pathways are the Toll, Imd, Jak/Stat, JNK, and insulin pathways. Activation of these and other pathways leads to pathogen killing via phagocytosis, melanization, cellular encapsulation, nodulation, lysis, RNAi-mediated virus destruction, autophagy and apoptosis. This review details these and other aspects of immunity in insects, and discusses how the immune and circulatory systems have co-adapted to combat infection, how hemocyte replication and differentiation takes place (hematopoiesis), how an infection prepares an insect for a subsequent infection (immune priming), how environmental factors such as temperature and the age of the insect impact the immune response, and how social immunity protects entire groups. Finally, this review highlights some underexplored areas in the field of insect immunobiology. PMID:26695127

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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 ...

  3. 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

  4. 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

  5. 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 ...

  6. 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. PMID:24647930

  7. 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,…

  8. SOCIAL INSECT PHEROMONES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Social insects include the social Hymenoptera (Formicidae, ants; Apidae, bees; Vespidae, wasps) and Isoptera (Termitidae, termites). Social interactions are required for effective food retrieval, brood and queen care, regulation of caste (sexuals/workers), recognition and exclusion of non-nestmates,...

  9. People and Insects.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides: (1) background information on how insects affect human lives, both positively and negatively, and on integrated pest management strategies; (2) student activities; and (3) materials (ready-to-copy games, puzzles, coloring pages, worksheets, and/or mazes). Each activity includes an objective, recommended age level(s), subject area(s),…

  10. 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...

  11. 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…

  12. 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.

  13. 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...

  14. 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)

  15. 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.

  16. Corn Insect Pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historically, the major corn insect pests have been corn rootworms (northern and western), European corn borer, and black cutworm. Bt-corn hybrids are effective against most of these pests. However, Bt-corn hybrids are not effective against corn leaf aphid, corn root aphid, sap beetles, corn rootwor...

  17. 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.

  18. Detection of insects in grain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Detecting insects hidden inside kernels of grain is important to grain buyers because internal infestations can result in insect fragments in products made from the grain, or, if the grain is stored before use, the insect population can increase and damage the grain further. In a study in the Unite...

  19. Insect Ferritins: typical or atypical?

    PubMed Central

    Pham, Daphne Q. D.; Winzerling, Joy J.

    2010-01-01

    Insects transmit millions of cases of disease each year, and cost millions of dollars in agricultural losses. The control of insect-borne diseases is vital for numerous developing countries, and the management of agricultural insect pests is a very serious business for developed countries. Control methods should target insect-specific traits in order to avoid non-target effects, especially in mammals. Since insect cells have had a billion years of evolutionary divergence from those of vertebrates, they differ in many ways that might be promising for the insect control field—especially, in iron metabolism because current studies have indicated that significant differences exist between insect and mammalian systems. Insect iron metabolism differs from that of vertebrates in the following respects. Insect ferritins have a heavier mass than mammalian ferritins. Unlike their mammalian counterparts, the insect ferritin subunits are often glycosylated and are synthesized with a signal peptide. The crystal structure of insect ferritin also shows a tetrahedral symmetry consisting of 12 heavy chain and 12 light chain subunits in contrast to that of mammalian ferritin that exhibits an octahedral symmetry made of 24 heavy chain and 24 light chain subunits. Insect ferritins associate primarily with the vacuolar system and serve as iron transporters—quite the opposite of the mammalian ferritins, which are mainly cytoplasmic and serve as iron storage proteins. This review will discuss these differences. PMID:20230873

  20. 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.

  1. 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

  2. Undergraduates' mental models about insect anatomy and insect life cycles

    NASA Astrophysics Data System (ADS)

    Diaz, Arlene Edith

    Educational studies focused on students' alternative conceptions have shown the importance of developing strategies to correct understanding. Identifying and comprehending student mental models are important since they may reflect alternate conceptions about scientific concepts. Mental models have been identified in various science education studies, but little is known about mental models undergraduates hold about insects. This research is significant because it identified mental models undergraduates have about insect anatomy and insect life cycles, exposed students to cognitive conflict by having them complete an online insect tutorial, and analyzed the effectiveness of this insect tutorial in correcting student understanding. An insect assessment was developed and administered pre- and post-instruction to probe students' mental models about insects. Different numbers of undergraduate students participated in different parts of the assessment; 276, 249, 166, and 58 students participated in the listing, drawing. definition, and life cycle parts of the assessment, respectively. The tutorial contained a variety of manipulated insect and non-insect images that challenged the students' understanding and generated cognitive conflict. This intervention guided students in replacing alternate conceptions with correct understanding. It was hypothesized that the tutorial would have a positive impact on student learning about insects. The results suggest that the tutorial had a positive impact on learning.

  3. [Protection against insects].

    PubMed

    Rudin, W

    2005-11-01

    Successful protection against haematophagous insects and ticks, especially in areas where transmission of diseases occurs, requires a consistent application of a combination of appropriate measures. However, this can never substitute a chemoprophylaxis. Which measures have to be used depends on the circumstances under which they have to work. Indoor, physical means such as mosquito-screens on doors and windows, air-conditioners, and bed nets can be used to keep the insects away. These measures can be supplemented or supported by insecticides used as knock-down sprays, by electrical evaporation or for the treatment of screens and bed nets. In the field, if it is not possible to avoid mosquito-areas during phases of activity, appropriate clothing and repellents must provide the protection. Bright, wide pants and shirts of dense weaving covering as much skin as bearable should be preferred. Repellents are sprays, lotions, milks or creams which are evenly applied to the skin to prevent insects from biting. They contain synthetic or natural active substances of substantially varying effectiveness. The gold standard since about 60 years is diethylbenzamine (DEET). There are a few other active substances with a lower risk of side effects, however, combined with a lower effectiveness mainly on people with a high attractiveness for mosquitoes. Products containing an extract of Eucalyptus citriodora provide the best protection amongst those with natural active substances. Wearing bracelets or necklaces treated with repellents, acoustic devices (buzzers), electrocuters, topical or systemic Vitamin B1 or eating garlic are useless measures to prevent insects from biting. PMID:16350532

  4. Interrogating an insect society

    PubMed Central

    Gadagkar, Raghavendra

    2009-01-01

    Insect societies such as those of ants, bees, and wasps consist of 1 or a small number of fertile queens and a large number of sterile or nearly sterile workers. While the queens engage in laying eggs, workers perform all other tasks such as nest building, acquisition and processing of food, and brood care. How do such societies function in a coordinated and efficient manner? What are the rules that individuals follow? How are these rules made and enforced? These questions are of obvious interest to us as fellow social animals but how do we interrogate an insect society and seek answers to these questions? In this article I will describe my research that was designed to seek answers from an insect society to a series of questions of obvious interest to us. I have chosen the Indian paper wasp Ropalidia marginata for this purpose, a species that is abundantly distributed in peninsular India and serves as an excellent model system. An important feature of this species is that queens and workers are morphologically identical and physiologically nearly so. How then does an individual become a queen? How does the queen suppress worker reproduction? How does the queen regulate the nonreproductive activities of the workers? What is the function of aggression shown by different individuals? How and when is the queen's heir decided? I will show how such questions can indeed be investigated and will emphasize the need for a whole range of different techniques of observation and experimentation. PMID:19487678

  5. 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. PMID:23393276

  6. Escape behaviors in insects.

    PubMed

    Card, Gwyneth M

    2012-04-01

    Escape behaviors are, by necessity, fast and robust, making them excellent systems with which to study the neural basis of behavior. This is especially true in insects, which have comparatively tractable nervous systems and members who are amenable to manipulation with genetic tools. Recent technical developments in high-speed video reveal that, despite their short duration, insect escape behaviors are more complex than previously appreciated. For example, before initiating an escape jump, a fly performs sophisticated posture and stimulus-dependent preparatory leg movements that enable it to jump away from a looming threat. This newfound flexibility raises the question of how the nervous system generates a behavior that is both rapid and flexible. Recordings from the cricket nervous system suggest that synchrony between the activity of specific interneuron pairs may provide a rapid cue for the cricket to detect the direction of an approaching predator and thus which direction it should run. Technical advances make possible wireless recording from neurons while locusts escape from a looming threat, enabling, for the first time, a direct correlation between the activity of multiple neurons and the time-course of an insect escape behavior. PMID:22226514

  7. 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

  8. Insect bite prevention.

    PubMed

    Moore, Sarah J; Mordue Luntz, Anne Jennifer; Logan, James G

    2012-09-01

    Protection from the bites of arthropod (insect and acarine) vectors of disease is the first line of defense against disease transmission and should be advised in all cases when traveling abroad. Details are described of the main approaches for the prevention of bites, including topical or skin repellents, impregnated clothing, bed nets, and spatial or aerial repellents and aerosols. The bionomics of the main arthropod vectors of disease are described along with photographic plates and tabulated advice to give the traveler. An in-depth treatment of the different protection methodologies provides an up-to-date overview of the technologies involved. PMID:22963776

  9. 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.

  10. 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....

  11. 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....

  12. 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...

  13. 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....

  14. 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....

  15. 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....

  16. 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...

  17. 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....

  18. 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…

  19. 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.

  20. 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

  1. RNAI: Future in insect management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA interference is a post-transcriptional, gene regulation mechanism found in virtually all plants and animals including insects. The demonstration of RNAi in insects and its successful use as a tool in the study of functional genomics opened the door to the development of a variety of novel, envir...

  2. 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

  3. 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.…

  4. 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…

  5. 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...

  6. Chickpea Ascochyta blight and insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early symptoms of Acochyta blight and insect damages were detected in the Paliuse region.This article informs chickpea scientists and growers about current disease and insect pest problems in the Palouse region. Ascochyta blight appeared in many chickpea fields and was severe in some fields. Insec...

  7. A Template for Insect Cryopreservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article is intended to update the reader on the progress made on insect embryo cryopreservation in the past 20 years and gives information for developing a protocol for cryopreserving insects by using a 2001 study as a template. The study used for the template is the cryopreservation of the Old...

  8. 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. PMID:27131327

  9. 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.

  10. 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

  11. 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

  12. 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...

  13. 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...

  14. Improving efficacy of Beauveria bassiana foliar treatments against Colorado potato beetle via manipulation of spray-application parameters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of hydraulic spray pressure and sprayer configuration on efficacy of foliar applications of B. bassiana against Leptinotarsa decemlineata larvae were evaluated during 4 field seasons. Treatments were applied to small plots using a tractor-mounted sprayer with nozzles mounted on swivels on sh...

  15. 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 ...

  16. 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...

  17. Integrated applications of Bacillus thuringiensis serovar. tenebrionis and Beauveria bassiana for biologically-based integrated pest management of Colorado potato beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research conducted over the past decade has indicated a low level of synergism and potentially high degree of complementarity between Bacillus thuringiensis (Bt)- and Beauveria bassiana (Bb)-based biopesticides applied for management of the Colorado potato beetle, Leptinotarsa decemlineata. In view...

  18. Enteric bacteria of field-collected Colorado potato beetle larvae inhibit growth of the entomopathogens Photorhabdus temperata and Beauveria bassiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In a prior study we provided evidence that the failure of the nematode Heterorhabditis marelatus Liu and Berry to reproduce in the Colorado potato beetle, Leptinotarsa decemlineata (Say), was due to interference from the enteric bacteria of the beetle. Specifically, the enteric bacteria inhibited th...

  19. 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.

  20. Eicosanoid actions in insect immunology

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  1. 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.

  2. 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 ...

  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'. PMID:27481779

  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 bites and stings (image)

    MedlinePlus

    Even though some insect bites or stings can be extremely painful they usually do not require emergency medical care. Although the stung or bitten area should be carefully observed for signs of infection or reaction to venom.

  7. 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...

  8. Pollen Recovery from Insects: Light Microscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous insect species feed on the pollen, nectar, and other plant exudates that are associated with flowers. As a result of this feeding activity, pollen becomes attached to the insects. Analysis of the pollen attached to these insects can reveal what insects eat, their dispersal patterns in and...

  9. 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...

  10. 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,…

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  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. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. Don't Let Insects Bug You!

    ERIC Educational Resources Information Center

    Abraham, Doc; Abraham, Katy

    1977-01-01

    Are you one of those people who feel that the only good insect is a dead one? Do you suffer from entomophobia--dread fear of insects? Such attitudes, fears, and prejudices stem from insect ignorance. Authors explain what insects are good for and give students a more realistic and fascinating view of their world. (Editor/RK)

  3. Multimodal stimulation of Colorado potato beetle reveals modulation of pheromone response by yellow light.

    PubMed

    Otálora-Luna, Fernando; Dickens, Joseph C

    2011-01-01

    Orientation of insects to host plants and conspecifics is the result of detection and integration of chemical and physical cues present in the environment. Sensory organs have evolved to be sensitive to important signals, providing neural input for higher order multimodal processing and behavioral output. Here we report experiments to determine decisions made by Colorado potato beetle (CPB), Leptinotarsa decemlineata, in response to isolated stimuli and multimodal combinations of signals on a locomotion compensator. Our results show that in complete darkness and in the absence of other stimuli, pheromonal stimulation increases attraction behavior of CPB as measured in oriented displacement and walking speed. However, orientation to the pheromone is abolished when presented with the alternative stimulation of a low intensity yellow light in a dark environment. The ability of the pheromone to stimulate these diurnal beetles in the dark in the absence of other stimuli is an unexpected but interesting observation. The predominance of the phototactic response over that to pheromone when low intensity lights were offered as choices seems to confirm the diurnal nature of the insect. The biological significance of the response to pheromone in the dark is unclear. The phototactic response will play a key role in elucidating multimodal stimulation in the host-finding process of CPB, and perhaps other insects. Such information might be exploited in the design of applications to attract and trap CPB for survey or control purposes and other insect pests using similar orientation mechanisms. PMID:21695167

  4. Improved Cultivation Systems for Isolation of the Colorado Potato Beetle Spiroplasma

    PubMed Central

    Konai, M.; Hackett, K. J.; Williamson, D. L.; Lipa, J. J.; Pollack, J. D.; Gasparich, G. E.; Clark, E. A.; Vacek, D. C.; Whitcomb, R. F.

    1996-01-01

    In North America, the Colorado potato beetle, Leptinotarsa decemlineata, is often infected with the host-specific, gut-inhabiting Colorado potato beetle spiroplasma (CPBS). CPBS is apparently a commensal, but it may be useful in biocontrol if it can be transformed to express an insect-lethal gene. Difficulty in cultivating the organism, however, has hindered the development of a suitable transformation system. In this study, we eliminated the need for coculturing CPBS with insect cells. CPBS was reliably isolated with the BBL Anaerobic GasPak Jar system (low redox, enhanced CO(inf2)), which was easier to use and less expensive than insect cell coculture methods. A further advantage is a reduction in contaminating insect cell components. Use of anaerobiosis should facilitate early-passage screening of isolates for extrachromosomal elements, for use in gene vector constructs. The unique spiral (decreasing amplitude of coils) morphology of CPBS was preserved by anaerobiosis. The use of low-pH (6.0 to 6.5) media allowed aerobic adaptation of CPBS to M1D and SP-4 broth media. These formulations permitted the first cultivation of CPBS on solid media, an accomplishment that will simplify the selection of molecular transformants. Potato beetles collected at four sites in Poland yielded CPBS strains similar to those previously obtained from populations in North America. PMID:16535407

  5. Discontinuous gas exchange in insects.

    PubMed

    Quinlan, Michael C; Gibbs, Allen G

    2006-11-01

    Insect respiratory physiology has been studied for many years, and interest in this area of insect biology has become revitalized recently for a number of reasons. Technical advances have greatly improved the precision, accuracy and ease with which gas exchange can be measured in insects. This has made it possible to go beyond classic models such as lepidopteran pupae and examine a far greater diversity of species. One striking result of recent work is the realization that insect gas exchange patterns are much more diverse than formerly recognized. Current work has also benefited from the inclusion of comparative methods that rigorously incorporate phylogenetic, ecological and life history information. We discuss these advances in the context of the classic respiratory pattern of insects, discontinuous gas exchange. This mode of gas exchange was exhaustively described in moth pupae in the 1950s and 1960s. Early workers concluded that discontinuous gas exchange was an adaptation to reduce respiratory water loss. This idea is no longer universally accepted, and several competing hypotheses have been proposed. We discuss the genesis of these alternative hypotheses, and we identify some of the predictions that might be used to test them. We are pleased to report that what was once a mature discipline, in which the broad parameters and adaptive significance of discontinuous gas exchange were thought to be well understood, is now a thriving and vigorous field of research. PMID:16870512

  6. Flower constancy in insect pollinators

    PubMed Central

    Ratnieks, Francis L.W.

    2011-01-01

    As first noted by Aristotle in honeybee workers, many insect pollinators show a preference to visit flowers of just one species during a foraging trip. This “flower constancy” probably benefits plants, because pollen is more likely to be deposited on conspecific stigmas. But it is less clear why insects should ignore rewarding alternative flowers. Many researchers have argued that flower constancy is caused by constraints imposed by insect nervous systems rather than because flower constancy is itself an efficient foraging method. We argue that this view is unsatisfactory because it both fails to explain why foragers flexibly adjust the degree of flower constancy and does not explain why foragers of closely related species show different degrees of constancy. While limitations of the nervous system exist and are likely to influence flower constancy to some degree, the observed behavioural flexibility suggests that flower constancy is a successful foraging strategy given the insect’s own information about different foraging options. PMID:22446521

  7. 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

  8. Line following terrestrial insect biobots.

    PubMed

    Latif, Tahmid; Bozkurt, Alper

    2012-01-01

    The present day technology falls short in offering centimeter scale mobile robots that can function effectively under unknown and dynamic environmental conditions. Insects, on the other hand, exhibit an unmatched ability to navigate through a wide variety of environments and overcome perturbations by successfully maintaining control and stability. In this study, we use neural stimulation systems to wirelessly navigate cockroaches to follow lines to enable terrestrial insect biobots. We also propose a system-on-chip based ZigBee enabled wireless neurostimulation backpack system with on-board tissue-electrode bioelectrical coupling verification. Such a capability ensures an electrochemically safe stimulation and avoids irreversible damage to the interface which is often misinterpreted as habituation of the insect to the applied stimulation. PMID:23366056

  9. 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.

  10. 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

  11. Insect Screening Results: Assessment of Corn Hybrids for Insect Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the growing season of 2006, the relatively dry environmental conditions in Tifton, Georgia were favorable for the rapid buildup of corn earworms, providing the potential for considerable damage to the corn crop. Six ear-feeding insects recorded in the order of infestation severity were: the...

  12. 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

  13. 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

  14. 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

  15. 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. PMID:25050958

  16. 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)

  17. 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

  18. 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)

  19. 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 ...

  20. The Curious Connection Between Insects and Dreams.

    PubMed

    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

  1. 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 ...

  2. 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...

  3. 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)

  4. 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)

  5. 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

  6. 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 ...

  7. 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…

  8. 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…

  9. Rearing insects on artificial diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects are reared in the laboratory for various purposes. They may be reared either on their natural food or artificial diets. Developing artificial diets may be difficult and time consuming but once optimized, artificial diets usually are simple to prepare and easy to use. Because they are process...

  10. 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...