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Find video protocols related to scientific articles indexed in Pubmed.
Genetic elimination of field-cage populations of Mediterranean fruit flies.
Proc. Biol. Sci.
PUBLISHED: 08-15-2014
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The Mediterranean fruit fly (medfly, Ceratitis capitata Wiedemann) is a pest of over 300 fruits, vegetables and nuts. The sterile insect technique (SIT) is a control measure used to reduce the reproductive potential of populations through the mass release of sterilized male insects that mate with wild females. However, SIT flies can display poor field performance, due to the effects of mass-rearing and of the irradiation process used for sterilization. The development of female-lethal RIDL (release of insects carrying a dominant lethal) strains for medfly can overcome many of the problems of SIT associated with irradiation. Here, we present life-history characterizations for two medfly RIDL strains, OX3864A and OX3647Q. Our results show (i) full functionality of RIDL, (ii) equivalency of RIDL and wild-type strains for life-history characteristics, and (iii) a high level of sexual competitiveness against both wild-type and wild-derived males. We also present the first proof-of-principle experiment on the use of RIDL to eliminate medfly populations. Weekly releases of OX3864A males into stable populations of wild-type medfly caused a successive decline in numbers, leading to eradication. The results show that genetic control can provide an effective alternative to SIT for the control of pest insects.
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Activity of flonicamid on the sweet potato whitely Bemisia tabaci (Homoptera: Aleyrodidae) and its natural enemies.
Pest Manag. Sci.
PUBLISHED: 02-19-2014
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Flonicamid is a novel systemic insecticide that acts as a feeding blocker with potential use against whiteflies within IPM control tactics. Flonicamid efficacy against Bemisia tabaci Mediterranean populations from Crete was examined, as well as side effects on selected beneficials used extensively in current IPM schemes.
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Framework for rapid assessment and adoption of new vector control tools.
Trends Parasitol.
PUBLISHED: 02-13-2014
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Evidence-informed health policy making is reliant on systematic access to, and appraisal of, the best available research evidence. This review suggests a strategy to improve the speed at which evidence is gathered on new vector control tools (VCTs) using a framework based on measurements of the vectorial capacity of an insect population to transmit disease. We explore links between indicators of VCT efficacy measurable in small-scale experiments that are relevant to entomological and epidemiological parameters measurable only in large-scale proof-of-concept randomised control trials (RCTs). We hypothesise that once RCTs establish links between entomological and epidemiological indicators then rapid evaluation of new products within the same product category may be conducted through smaller scale experiments without repetition of lengthy and expensive RCTs.
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Country-level operational implementation of the Global Plan for Insecticide Resistance Management.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 05-21-2013
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Malaria control is reliant on the use of long-lasting pyrethroid-impregnated nets and/or indoor residual spraying (IRS) of insecticide. The rapid selection and spread of operationally significant pyrethroid resistance in African malaria vectors threatens our ability to sustain malaria control. Establishing whether resistance is operationally significant is technically challenging. Routine monitoring by bioassay is inadequate, and there are limited data linking resistance selection with changes in disease transmission. The default is to switch insecticides when resistance is detected, but limited insecticide options and resistance to multiple insecticides in numerous locations make this approach unsustainable. Detailed analysis of the resistance situation in Anopheles gambiae on Bioko Island after pyrethroid resistance was detected in this species in 2004, and the IRS program switched to carbamate bendiocarb, has now been undertaken. The pyrethroid resistance selected is a target-site knock-down resistance kdr-form, on a background of generally elevated metabolic activity, compared with insecticide-susceptible A. gambiae, but the major cytochrome P450-based metabolic pyrethroid resistance mechanisms are not present. The available evidence from bioassays and infection data suggests that the pyrethroid resistance mechanisms in Bioko malaria vectors are not operationally significant, and on this basis, a different, long-lasting pyrethroid formulation is now being reintroduced for IRS in a rotational insecticide resistance management program. This will allow control efforts to be sustained in a cost-effective manner while reducing the selection pressure for resistance to nonpyrethroid insecticides. The methods used provide a template for evidence-based insecticide resistance management by malaria control programs.
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Insecticide resistance status in the major WNV vector Culex pipiens from Greece.
Pest Manag. Sci.
PUBLISHED: 04-09-2013
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One of the largest West Nile Virus (WNV) outbreaks in Europe occurred in Greece in 2010. Use of insecticides against Cx. pipiens was substantially scaled up, as an emergency tool. Although mosquito control has been based on insecticides for several decades in Greece, insecticide resistance data is not available.
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Molecular analysis of resistance to acaricidal spirocyclic tetronic acids in Tetranychus urticae: CYP392E10 metabolizes spirodiclofen, but not its corresponding enol.
Insect Biochem. Mol. Biol.
PUBLISHED: 02-01-2013
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Spirodiclofen is one of the most recently developed acaricides and belongs to the new family of spirocyclic tetronic acids (ketoenols). This new acaricidal family is an important chemical tool in resistance management strategies providing sustainable control of spider mites such as Tetranychus urticae. Spirodiclofen targets lipid biosynthesis mediated by direct inhibition of acetyl coenzyme A carboxylase (ACCase). In this study, we investigated two genetically distant spider mite strains with high resistance to spirodiclofen. Despite the strong resistance levels to spirodiclofen (up to 680-fold), only limited cross-resistance with other members of this group such as spiromesifen and spirotetramat could be detected. Amplification and sequencing of the ACCase gene from resistant and susceptible strains did not reveal common non-synonymous mutations, and expression levels of ACCase were similar in both resistant and susceptible strains, indicating the absence of target-site resistance. Furthermore, we collected genome-wide expression data of susceptible and resistant T. urticae strains using microarray technology. Analysis of differentially expressed genes revealed a broad response, but within the overlap of two resistant strains, several cytochrome P450s were prominent. Quantitative PCR confirmed the constitutive over-expression of CYP392E7 and CYP392E10 in resistant strains, and CYP392E10 expression was highly induced by spirodiclofen. Furthermore, stage specific expression profiling revealed that expression levels were not significantly different between developing stages, but very low in eggs, matching the age-dependent resistance pattern previously observed. Functional expression of CYP392E7 and CYP392E10 confirmed that CYP392E10 (but not CYP392E7) metabolizes spirodiclofen by hydroxylation as identified by LC-MS/MS, and revealed cooperative substrate binding and a Km of 43 ?M spirodiclofen. CYP392E10 also metabolizes spiromesifen, but not spirotetramat. Surprisingly, no metabolism of the hydrolyzed spirodiclofen-enol metabolite could be detected. These findings are discussed in the light of a likely resistance mechanism.
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Distribution and hybridization of Culex pipiens forms in Greece during the West Nile virus outbreak of 2010.
Infect. Genet. Evol.
PUBLISHED: 01-20-2013
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In 2010, an outbreak of West Nile virus (WNV) infections occurred in the region of Thessaloniki, Central Macedonia, in northern Greece. During this period, Culex pipiens sensu stricto mosquitoes were found infected by WNV lineage 2. Cx. pipiens s.s. presents two distinct biological forms, denoted molestus and pipiens. Hybrids between the two forms may potentiate the accidental transmission of WNV to humans. We have genetically characterized the form composition of Cx. pipiens s.s. samples collected during the outbreak from the region of Thessaloniki, where WNV cases occurred, and from the region Schinias-Marathonas, with no reported cases at the time. Information on bird fauna was also obtained for the two regions. Application of the CQ11FL diagnostic marker revealed a 350 bp variant of the pipiens-specific allele. Sympatric pipiens and molestus populations were detected in Thessaloniki, whereas Schinias-Marathonas presented a more genetically homogenous molestus population. A pattern of asymmetric introgression between molestus and pipiens was also observed in Thessaloniki. The presence of hybrids between molestus and pipiens forms suggests a greater receptivity of the Thessaloniki region for the establishment of WNV zoonotic cycles. However, the Schinias-Marathonas region also displayed characteristics to sustain WNV transmission cycles. These observations highlight the importance of maintaining active surveillance systems in selected regions geographically located within the range of major migratory bird flyways.
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Pymetrozine is hydroxylated by CYP6CM1, a cytochrome P450 conferring neonicotinoid resistance in Bemisia tabaci.
Pest Manag. Sci.
PUBLISHED: 01-16-2013
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Resistance to neonicotinoid insecticides such as imidacloprid in the cotton whitefly, Bemisia tabaci, is linked to its hydroxylation by constitutively overexpressed CYP6CM1, a cytochrome P450 enzyme. Here, an investigation was conducted to establish whether CYP6CM1 functionally expressed in Sf9 cells also detoxifies pymetrozine, a selective homopteran feeding blocker known to be cross-resistant to neonicotinoids in whiteflies.
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Analysis of the Olive Fruit Fly Bactrocera oleae Transcriptome and Phylogenetic Classification of the Major Detoxification Gene Families.
PLoS ONE
PUBLISHED: 01-01-2013
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The olive fruit fly Bactrocera oleae has a unique ability to cope with olive flesh, and is the most destructive pest of olives worldwide. Its control has been largely based on the use of chemical insecticides, however, the selection of insecticide resistance against several insecticides has evolved. The study of detoxification mechanisms, which allow the olive fruit fly to defend against insecticides, and/or phytotoxins possibly present in the mesocarp, has been hampered by the lack of genomic information in this species. In the NCBI database less than 1,000 nucleotide sequences have been deposited, with less than 10 detoxification gene homologues in total. We used 454 pyrosequencing to produce, for the first time, a large transcriptome dataset for B. oleae. A total of 482,790 reads were assembled into 14,204 contigs. More than 60% of those contigs (8,630) were larger than 500 base pairs, and almost half of them matched with genes of the order of the Diptera. Analysis of the Gene Ontology (GO) distribution of unique contigs, suggests that, compared to other insects, the assembly is broadly representative for the B. oleae transcriptome. Furthermore, the transcriptome was found to contain 55 P450, 43 GST-, 15 CCE- and 18 ABC transporter-genes. Several of those detoxification genes, may putatively be involved in the ability of the olive fruit fly to deal with xenobiotics, such as plant phytotoxins and insecticides. In summary, our study has generated new data and genomic resources, which will substantially facilitate molecular studies in B. oleae, including elucidation of detoxification mechanisms of xenobiotic, as well as other important aspects of olive fruit fly biology.
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A simple colorimetric assay for specific detection of glutathione-S transferase activity associated with DDT resistance in mosquitoes.
PLoS Negl Trop Dis
PUBLISHED: 05-05-2010
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Insecticide-based methods represent the most effective means of blocking the transmission of vector borne diseases. However, insecticide resistance poses a serious threat and there is a need for tools, such as diagnostic tests for resistance detection, that will improve the sustainability of control interventions. The development of such tools for metabolism-based resistance in mosquito vectors lags behind those for target site resistance mutations.
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Transcriptomics and disease vector control.
BMC Biol.
PUBLISHED: 04-12-2010
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Next-generation sequencing can be used to compare transcriptomes under different conditions. A study in BMC Genomics applies this approach to investigating the effects of exposure to a range of xenobiotics on changes in gene expression in the larvae of Aedes aegypti, the mosquito vector of dengue fever.
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Acaricide resistance mechanisms in the two-spotted spider mite Tetranychus urticae and other important Acari: a review.
Insect Biochem. Mol. Biol.
PUBLISHED: 04-08-2010
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The two-spotted spider mite Tetranychus urticae Koch is one of the economically most important pests in a wide range of outdoor and protected crops worldwide. Its control has been and still is largely based on the use of insecticides and acaricides. However, due to its short life cycle, abundant progeny and arrhenotokous reproduction, it is able to develop resistance to these compounds very rapidly. As a consequence, it has the dubious reputation to be the"most resistant species" in terms of the total number of pesticides to which populations have become resistant, and its control has become problematic in many areas worldwide. Insecticide and acaricide resistance has also been reported in the ectoparasite Sarcoptes scabiei, the causative organism of scabies, and other economically important Acari, such as the Southern cattle tick Rhipicephalus microplus, one of the biggest arthropod threats to livestock, and the parasitic mite Varroa destructor, a major economic burden for beekeepers worldwide. Although resistance research in Acari has not kept pace with that in insects, a number of studies on the molecular mechanisms responsible for the resistant phenotype has been conducted recently. In this review, state-of-the-art information on T. urticae resistance, supplemented with data on other important Acari has been brought together. Considerable attention is given to the underlying resistance mechanisms that have been elucidated at the molecular level. The incidence of bifenazate resistance in T. urticae is expanded as an insecticide resistance evolutionary paradigm in arthropods.
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Structural model and functional characterization of the Bemisia tabaci CYP6CM1vQ, a cytochrome P450 associated with high levels of imidacloprid resistance.
Insect Biochem. Mol. Biol.
PUBLISHED: 07-14-2009
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The neonicotinoid imidacloprid is one of the most important insecticides worldwide. It is used extensively against the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae), an insect pest of eminent importance globally, which was also the first pest to develop high levels of resistance against imidacloprid and other neonicotinoids in the field. Recent reports indicated that in both the B and Q biotypes of B. tabaci, the resistant phenotype is associated with over-expression of the cytochrome P450 gene CYP6CM1. In this study, molecular docking and dynamic simulations were used to analyze interactions of imidacloprid with the biotype Q variant of the CYP6CM1 enzyme (CYP6CM1vQ). The binding mode with the lowest energy in the enzyme active site, the key amino acids involved (i.e. Phe-130 and Phe-226), and the putative hydroxylation site (lowest distance to carbon 5 of the imidazolidine ring system of imidacloprid) were predicted. Heterologous expression of the CYP6CM1vQ confirmed the accuracy of our predictions and demonstrated that the enzyme catalyses the hydroxylation of imidacloprid to its less toxic 5-hydroxy form (K(cat) = 3.2 pmol/min/pmol P450, K(m) = 36 microM). The data identify CYP6CM1vQ as a principle target for inhibitor design, aimed at inactivating insecticide-metabolizing P450s in natural insect pest populations.
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Current status of insecticide resistance in Q biotype Bemisia tabaci populations from Crete.
Pest Manag. Sci.
PUBLISHED: 04-03-2009
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A major problem of crop protection in Crete, Greece, is the control of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) with chemical insecticides owing to the rapid development of resistance. The aim of this study was to investigate the establishment of resistance and the underlying mechanisms to major insecticide classes with classical bioassays and known biochemical resistance markers.
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Short report: a multiplex PCR assay for simultaneous genotyping of kdr and ace-1 loci in Anopheles gambiae.
Am. J. Trop. Med. Hyg.
PUBLISHED: 02-05-2009
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The selection of insecticide-resistant genotypes in Anopheles gambiae, the most important malaria vector in Africa, makes disease control problematic in several endemic areas. The early detection and monitoring of resistance associated mutations in field mosquito populations is essential for the application of successful insecticide-based control interventions. Currently, the surveillance of these mutations is performed using individual assays, some of which require sophisticated and expensive equipment. Here we describe a novel multiplex polymerase chain reaction-based assay for detecting simultaneously the five single nucleotide polymorphisms in the voltage-gated sodium channel and the ace-1 genes, which have been associated with the mosquito response to most commonly used insecticides.
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Resurgence of the cotton bollworm Helicoverpa armigera in northern Greece associated with insecticide resistance.
Insect Sci.
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Helicoverpa armigera has been controlled effectively with chemical insecticides in the major cotton crop production areas of northern Greece for many years. However, a resurgence of the pest was observed in 2010, which significantly affected crop production. During a 4-year survey (2007-2010), we examined the insecticide resistance status of H. armigera populations from two major and representative cotton production areas in northern Greece against seven insecticides (chlorpyrifos, diazinon, methomyl, alpha-cypermethrin, cypermethrin, gamma-cyhalothrin and endosulfan). Full dose-response bioassays on third instar larvae were performed by topical application. Lethal doses at 50% were estimated by probit analysis and resistance factors (RF) were calculated, compared to a susceptible laboratory reference strain. Resistance levels were relatively moderate until 2009, with resistance ratios below 10-fold for organophosphates and carbamates and up to 16-fold for the pyrethroid alpha-cypermethrin. However, resistance rose to 46- and 81-fold for chlorpyrifos and alpha-cypermethrin, respectively in 2010, when the resurgence of the pest was observed. None of the known pyrethroid resistance mutations were found in the pyrethroid-resistant insects. The possible association between resistance and H. armigera resurgence in Greece is discussed.
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A link between host plant adaptation and pesticide resistance in the polyphagous spider mite Tetranychus urticae.
Proc. Natl. Acad. Sci. U.S.A.
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Plants produce a wide range of allelochemicals to defend against herbivore attack, and generalist herbivores have evolved mechanisms to avoid, sequester, or detoxify a broad spectrum of natural defense compounds. Successful arthropod pests have also developed resistance to diverse classes of pesticides and this adaptation is of critical importance to agriculture. To test whether mechanisms to overcome plant defenses predispose the development of pesticide resistance, we examined adaptation of the generalist two-spotted spider mite, Tetranychus urticae, to host plant transfer and pesticides. T. urticae is an extreme polyphagous pest with more than 1,100 documented hosts and has an extraordinary ability to develop pesticide resistance. When mites from a pesticide-susceptible strain propagated on bean were adapted to a challenging host (tomato), transcriptional responses increased over time with ~7.5% of genes differentially expressed after five generations. Whereas many genes with altered expression belonged to known detoxification families (like P450 monooxygenases), new gene families not previously associated with detoxification in other herbivores showed a striking response, including ring-splitting dioxygenase genes acquired by horizontal gene transfer. Strikingly, transcriptional profiles of tomato-adapted mites resembled those of multipesticide-resistant strains, and adaptation to tomato decreased the susceptibility to unrelated pesticide classes. Our findings suggest key roles for both an expanded environmental response gene repertoire and transcriptional regulation in the life history of generalist herbivores. They also support a model whereby selection for the ability to mount a broad response to the diverse defense chemistry of plants predisposes the evolution of pesticide resistance in generalists.
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A new dibenzoylhydrazine with insecticidal activity against Anopheles mosquito larvae.
Pest Manag. Sci.
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Dibenzoylhydrazine (DBH) compounds have been applied successfully as environmentally safe insecticides against lepidopteran larvae and ground-dwelling coleopterans, but their potential to combat mosquito larvae is largely unknown. Here, toxicity tests of three commercial DBHs (tebufenozide, methoxyfenozide and halofenozide) and one experimental DBH (KU-106) against larvae of Anopheles gambiae, the major vector for human malaria, are reported.
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Effect of DMI-resistance mechanisms on cross-resistance patterns, fitness parameters and aflatoxin production in Aspergillus parasiticus Speare.
Fungal Genet. Biol.
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Aspergillus parasiticus mutant strains resistant to DMIs were isolated in a high mutation frequency after UV-mutagenesis and selection on media containing flusilazole. Two different resistant phenotypes, R(1) and R(2), on the basis of their aflatoxigenic ability were identified. All R(1) mutant strains produced aflatoxins at concentrations significantly higher (up to 3-fold) than the wild-type parent strain on yeast extract sucrose medium, whereas the majority of mutant strains (R(2) phenotype) lost their aflatoxigenic ability. Real-time PCR analysis of the expression levels of the aflR gene, a pathway transcriptional regulatory gene in aflatoxin biosynthesis, showed that this gene was not expressed in R(2) mutant strains tested. Study of fitness determining parameters showed that most flusilazole-resistant mutant strains had mycelial growth rate, sporulation and spore germination lower that the sensitive one. Cross-resistance studies with other fungicides showed that all R(1) mutant strains were also resistant to the DMIs imazalil and tebuconazole, but retained their parental sensitivity to fungicides affecting other metabolic pathways and/or cellular processes. Contrary to the above, all R(2) mutant strains exhibited a low to moderate multi-drug resistance to DMIs and to several other fungicide classes. Two different homologous genes, cyp51A and cyp51B, encoding C-14 alpha sterol demethylase (Cyp51) and an mdr gene encoding an ATP-binding cassette protein which may be involved in multidrug resistance were cloned and characterized. Sequence comparison of cyp51A gene revealed an amino acid substitution from glycine (GGG) to tryptophan (TGG) at position 54 (G54W) in two out of three of R(1) mutant strains. Analysis of deduced amino acid sequence of cyp51B showed that no mutations were associated with DMI resistance. Study for the transcriptional levels of cyp51A showed that this gene was over-expressed in the third aflatoxigenic mutant strain. Neither amino acid substitutions nor an overexpression of the cyp51A gene were found in the R(2) mutant strains tested. Real-time PCR analysis showed high levels (up to 25-fold higher) of the mdr transcript in all R(2) mutant strains tested. This is the first report describing the existence of two cyp51 genes and a potential mdr gene coding for an ATP binding cassette protein in A. parasiticus. These results also indicate that multiple biochemical mechanisms, including target-site modification due to mutation at cyp51A gene, overexpression of cyp51A gene and the function of an ABC transporter protein, are responsible for DMI-resistance in A. parasiticus. Our findings suggest that A. parasiticus have the genetic and biochemical potential for the appearance of highly aflatoxigenic DMI-resistant isolates in the field.
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Truncated transcripts of nicotinic acetylcholine subunit gene Bd?6 are associated with spinosad resistance in Bactrocera dorsalis.
Insect Biochem. Mol. Biol.
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Spinosad-resistance mechanisms of Bactrocera dorsalis, one of the most important agricultural pests worldwide, were investigated. Resistance levels to spinosad in a B. dorsalis strain from Taiwan were more than 2000-fold, but showed no cross resistance to imidacloprid or fipronil. Combined biochemical and synergistic data indicated that target-site insensitivity is the major resistance component. The gene encoding the nAChR subunit alpha 6 (Bd?6), the putative molecular target of spinosad, was isolated using PCR and RACE techniques. The full-length cDNA of Bd?6 from spinosad-susceptible strains had an open reading frame of 1467 bp and codes for a typical nAChR subunit. Two isoforms of exon 3 (3a and 3b) and exon 8 (8a and 8b), and four full-length splicing variants were found in the susceptible strain. All transcripts from the spinosad-resistant strain were truncated and coded for apparently non-functional Bd?6. Genetic linkage analysis further associated spinosad-resistance phenotype with the truncated Bd?6 forms. This finding is consistent with a previous study in Plutella xylostella. Small deletions and insertions and consequent premature stop codons in exon 7 were associated with the truncated transcripts at the cDNA level. Analysis of genomic DNA sequences (intron 2 and exons 3-6) failed to detect exon 5 in resistant flies. In addition, a mutation in Bd?6 intron 2, just before the truncated/mis-splicing region and in same location with a mutation previously reported in the Pxyl?6 gene, was identified in the resistant flies. RNA editing was investigated but was not found to be associated with resistance. While the demonstration of truncated transcripts causing resistance was outlined, the mechanism responsible for generating truncated transcripts remains unknown.
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Use of mutagenesis, genetic mapping and next generation transcriptomics to investigate insecticide resistance mechanisms.
PLoS ONE
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Insecticide resistance is a worldwide problem with major impact on agriculture and human health. Understanding the underlying molecular mechanisms is crucial for the management of the phenomenon; however, this information often comes late with respect to the implementation of efficient counter-measures, particularly in the case of metabolism-based resistance mechanisms. We employed a genome-wide insertional mutagenesis screen to Drosophila melanogaster, using a Minos-based construct, and retrieved a line (MiT[w(-)]3R2) resistant to the neonicotinoid insecticide Imidacloprid. Biochemical and bioassay data indicated that resistance was due to increased P450 detoxification. Deep sequencing transcriptomic analysis revealed substantial over- and under-representation of 357 transcripts in the resistant line, including statistically significant changes in mixed function oxidases, peptidases and cuticular proteins. Three P450 genes (Cyp4p2, Cyp6a2 and Cyp6g1) located on the 2R chromosome, are highly up-regulated in mutant flies compared to susceptible Drosophila. One of them (Cyp6g1) has been already described as a major factor for Imidacloprid resistance, which validated the approach. Elevated expression of the Cyp4p2 was not previously documented in Drosophila lines resistant to neonicotinoids. In silico analysis using the Drosophila reference genome failed to detect transcription binding factors or microRNAs associated with the over-expressed Cyp genes. The resistant line did not contain a Minos insertion in its chromosomes, suggesting a hit-and-run event, i.e. an insertion of the transposable element, followed by an excision which caused the mutation. Genetic mapping placed the resistance locus to the right arm of the second chromosome, within a ?1 Mb region, where the highly up-regulated Cyp6g1 gene is located. The nature of the unknown mutation that causes resistance is discussed on the basis of these results.
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Gene amplification, ABC transporters and cytochrome P450s: unraveling the molecular basis of pyrethroid resistance in the dengue vector, Aedes aegypti.
PLoS Negl Trop Dis
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Pyrethroid insecticides are widely utilized in dengue control. However, the major vector, Aedes aegypti, is becoming increasingly resistant to these insecticides and this is impacting on the efficacy of control measures. The near complete transcriptome of two pyrethroid resistant populations from the Caribbean was examined to explore the molecular basis of this resistance.
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Control of the olive fruit fly using genetics-enhanced sterile insect technique.
BMC Biol.
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The olive fruit fly, Bactrocera oleae, is the major arthropod pest of commercial olive production, causing extensive damage to olive crops worldwide. Current control techniques rely on spraying of chemical insecticides. The sterile insect technique (SIT) presents an alternative, environmentally friendly and species-specific method of population control. Although SIT has been very successful against other tephritid pests, previous SIT trials on olive fly have produced disappointing results. Key problems included altered diurnal mating rhythms of the laboratory-reared insects, resulting in asynchronous mating activity between the wild and released sterile populations, and low competitiveness of the radiation-sterilised mass-reared flies. Consequently, the production of competitive, male-only release cohorts is considered an essential prerequisite for successful olive fly SIT.
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