| digestive enzyme as benchmark for insecticide resistance development in culex pipiens larvae to chemical and bacteriologic insecticides. | this work monitored changes in some digestive enzymes (trypsin and aminopeptidase) associated with the building up of resistance in cx. pipiens larvae to two chemical insecticides (methomyl and/or malathion) and one biological insecticide (bacillus thuringiensis-h14 or b.t h 14). the lc50 value of methomyl for both field- and the 12th generation (f12) of the selected strain was 1.789 ppm and 8.925 ppm respectively. the lc50 value of malathion for both field and the f12 of the selected strain was ... | 2013 | 23697030 |
| differential role of manduca sexta aminopeptidase-n and alkaline phosphatase in the mode of action of cry1aa, cry1ab, and cry1ac toxins from bacillus thuringiensis. | aminopeptidase-n (apn1) and alkaline phosphatase (alp) proteins located in the midgut epithelium of manduca sexta have been implicated as receptors for cry1aa, cry1ab, and cry1ac insecticidal proteins produced by bacillus thuringiensis subsp. kurstaki. in this study, we analyzed the roles of alp and apn1 in the toxicity of these three cry1a proteins. ligand blot analysis using brush border membrane vesicles of m. sexta showed that cry1aa and cry1ab bind preferentially to alp during early instars ... | 2013 | 23686267 |
| decolorization of dyehouse effluent and biodegradation of congo red by bacillus thuringiensis run1. | a dye-decolorizing bacterium was isolated from a soil sample and identified as bacillus thuringiensis using 16s rrna sequencing. the bacterium was able to decolorize three different textile dyes, namely, reactive blue 13, reactive red 58, and reactive yellow 42, and a real dyehouse effluent up to 80-95% within 6 h. some non-textile industrially important dyes were also decolorized to different extents. fourier transform infrared spectroscopy and gas chromatography-mass spectrometer analysis of t ... | 2013 | 23676913 |
| high-throughput identification of promoters and screening of highly active promoter-5'-utr dna region with different characteristics from bacillus thuringiensis. | in bacteria, both promoters and 5'-untranslated regions (5'-utrs) of mrnas play vital regulatory roles in gene expression. in this study, we identified 1203 active promoter candidates in bacillus thuringiensis through analysis of the genome-wide tsss based on the transcriptome data. there were 11 types of σ-factor and 34 types of transcription factor binding sites found in 723 and 1097 active promoter candidates, respectively. moreover, within the 1203 transcriptional units (tus), most (52%) of ... | 2013 | 23675447 |
| bacillus thuringiensis cry4ba toxin employs two receptor-binding loops for synergistic interactions with cyt2aa2. | we previously demonstrated that co-expression in escherichia coli of bacillus thuringiensis (bt) subsp. israelensis cry4ba and bt subsp. darmstadiensis cyt2aa2 shows high synergistic toxicity against target mosquito larvae. here, further insights into synergistic interactions between these two toxins were revealed through bioactivity restoration of particular inactive cry4ba-mutant toxins altered within the receptor-binding domain. specific mutations at β2-β3 (y332a) or β4-β5 (f364a) loops, but ... | 2013 | 23665023 |
| [crystal formation peculiarities in pigmented cultures of bacillus thuringiensis]. | a direct correlation has been established between pink-colored pigmentation and the production of insecticide crystals (toxins) for some bacillus thuringiensis (bt) pigmented cultures. this regularity was for the first time determined by us for bt strains ofthe h3, h10, and h16 serotype. pigment-free clones of these serotypes do not produce crystals. a correlation was not observed in the case of h14 serotype strains with oval inclusions. the revealed correlation makes it possible to distinguish ... | 2013 | 23662449 |
| aphicidal efficacy of scorpion- and spider-derived neurotoxins. | insect-specific neurotoxins that act within the insect hemocoel (body cavity) represent an untapped resource for insect pest management. on the basis of recent advances made in development of appropriate delivery systems for transport of these toxins from the insect gut, across the gut epithelium to their target site, we screened neurotoxins derived from scorpion or spider venom for efficacy against the pea aphid, acyrthosiphon pisum, and the green peach aphid, myzus persicae. toxins were select ... | 2013 | 23651761 |
| sodium solute symporter and cadherin proteins act as bacillus thuringiensis cry3ba toxin functional receptors in tribolium castaneum. | understanding how bacillus thuringiensis (bt) toxins interact with proteins in the midgut of susceptible coleopteran insects is crucial to fully explain the molecular bases of bt specificity and insecticidal action. in this work, aminopeptidase n (tcapn-i), e-cadherin (tccad1), and sodium solute symporter (tcsss) have been identified by ligand blot as putative cry3ba toxin-binding proteins in tribolium castaneum (tc) larvae. rna interference knockdown of tccad1 or tcsss proteins resulted in decr ... | 2013 | 23645668 |
| existence of lysogenic bacteriophages in bacillus thuringiensis type strains. | we screened the existence of bacteriophages in 67 bacillus thuringiensis type strains by phage dna extraction and pcr using phage terminase small subunit (ters)-specific primers to the supernatants and the precipitated pellets of bt cultures, and by transmission electron microscopy. the various bacteriophages were observed from the supernatants of 22 type strains. ten type strains showed the extracted phage dnas and the amplified fragment by ters pcr but 12 type strains showed only the phage dna ... | 2013 | 23632013 |
| two's a crowd: phenotypic adjustments and prophylaxis in anticarsia gemmatalis larvae are triggered by the presence of conspecifics. | defence from parasites and pathogens involves a cost. thus, it is expected that organisms use this only at high population densities, where the risk of pathogen transmission may be high, as proposed by the "density-dependent prophylaxis" (ddp) hypothesis. these predictions have been tested in a wide range of insects, both in comparative and experimental studies. we think it pertinent to consider a continuum between solitarious and gregarious living insects, wherein: (1) solitarious insects are t ... | 2013 | 23626700 |
| field evaluation of arbuscular mycorrhizal fungal colonization in bacillus thuringiensis toxin-expressing (bt) and non-bt maize. | the cultivation of genetically engineered bacillus thuringiensis toxin-expressing (bt) maize continues to increase worldwide, yet the effects of bt crops on arbuscular mycorrhizal fungi (amf) in soil are poorly understood. in this field experiment, we investigated the impact of seven different genotypes of bt maize and five corresponding non-bt parental cultivars on amf and evaluated plant growth responses at three different physiological time points. plants were harvested 60 days (active growth ... | 2013 | 23624473 |
| microbial degradation of fipronil by bacillus thuringiensis. | fipronil, a phenyl pyrazole insecticide has been found to be effective for the control of various insect pests. due to its higher persistence in soil bioremediation is a promising approach to degrade the pesticide from soil. isolation and identification of soil microbes was conducted for bioremediation of fipronil contaminated soils. soil samples collected from different sugarcane growing fields in gurdaspur district with extensive use of pesticide history served as a source of pesticide degradi ... | 2013 | 23618775 |
| quantitative genetic analysis of cry1ab tolerance in ostrinia nubilalis spanish populations. | tolerance to bacillus thuringiensis cry1ab toxin in spanish ostrinia nubilalis populations was analyzed by quantitative genetic techniques, using isolines established from field-derived insects. f1 offspring was tested for susceptibility to trypsin activated cry1ab using a concentration that caused a mean larval mortality of 87% (±17% sd). the progeny of the most tolerant isolines (that had shown mortalities lower than 60%) was crossed to obtain the f2 generation that was exposed to the same cry ... | 2013 | 23612057 |
| expression of mosquito-larvicidal toxin genes under the control of a native promoter in enterobacter amnigenus an11. | enterobacter amnigenus an11, that can colonize the gut of mosquito larva, is an alternative toxin-producing host to be used as a mosquito control since it is able to float in the feeding zone of mosquito larvae. to produce mosquito-larvicidal toxins in this bacterium, a native promoter has been identified from its genomic dna. the promoter exhibited consensus sequences for -35 and -10 regions of bacterial promoters and constitutively drove the expression of gfp. this promoter was inserted into r ... | 2013 | 23609231 |
| highly efficient enzymatic preparation of c-di-amp using the diadenylate cyclase disa from bacillus thuringiensis. | cyclic 3',5'-diadenosine monophosphate (c-di-amp) is a newly recognized bacterial nucleotide second messenger molecule. in addition, it has been shown to be a potential vaccine adjuvant. although multiple methods are available for c-di-amp synthesis, the yields are low and the purification procedures are laborious. here, we report an enzymatic method for more efficient and economical c-di-amp synthesis using a diadenylate cyclase disa from bacillus thuringiensis bmb 171 (btdisa). after overexpre ... | 2013 | 23608499 |
| transcriptional regulation and characteristics of a novel n-acetylmuramoyl-l-alanine amidase gene involved in bacillus thuringiensis mother cell lysis. | in bacillus thuringiensis, a novel n-acetylmuramoyl-l-alanine amidase gene (named cwlb) was detected, and the cwlb protein was purified and characterized. reverse transcription-pcr (rt-pcr) results indicated that cwlb and an upstream gene (named cwla) formed one transcriptional unit. 5' rapid amplification of cdna ends (5'-race)-pcr and transcriptional fusions with the lacz gene indicated that transcription of the operon was directed by a promoter, p(cwla), which is located upstream from the cwl ... | 2013 | 23603740 |
| resistance to bt maize in mythimna unipuncta (lepidoptera: noctuidae) is mediated by alteration in cry1ab protein activation. | bt maize cultivars based on the event mon810 (expressing cry1ab) have shown high efficacy for controlling corn borers. however, their efficiency for controlling some secondary lepidopteran pests such as mythimna unipuncta has been questioned, raising concerns about potential outbreaks and its economic consequences. we have selected a resistant strain (mr) of m. unipuncta, which is capable of completing its life cycle on bt maize and displays a similar performance when feeding on both bt and non- ... | 2013 | 23603093 |
| tribolium castaneum apolipophorin-iii acts as an immune response protein against bacillus thuringiensis cry3ba toxic activity. | in this study, a 2.1-fold apolipophorin-iii mrna up-regulation was found in tribolium castaneum larvae challenged with bacillus thuringiensis cry3ba spore-crystal mixture. knockdown of apolipophorin-iii by rnai resulted in increased t. castaneum larvae susceptibility following cry3ba spore-crystal treatment, demonstrating apolipophorin-iii involvement in insect defense against b. thuringiensis. we showed that apolipophorin-iii participates in t. castaneum immune response to b. thuringiensis acti ... | 2013 | 23602900 |
| iron regulates bacillus thuringiensis haemolysin hlyii gene expression during insect infection. | bacillus thuringiensis (bt) is a spore-forming entomopathogen broadly used in agriculture crop. the haemolysin hlyii is an important bt virulence factor responsible for insect death. in this work, we focused on the regulation of the hlyii gene throughout the bacterial growth in vitro and in vivo during insect infection. we show that hlyii regulation depends on the global regulator fur. this regulation occurs independently of hlyiir, the other known regulator of hlyii gene expression. moreover, w ... | 2013 | 23598183 |
| production of the bioinsecticide bacillus thuringiensis subsp. israelensis with deltamethrin increases toxicity towards mosquito larvae. | bacillus thuringiensis subsp. israelensis is a bioinsecticide used for larval mosquito control and it represents a safe alternative to chemical insecticides. despite its environmental safety, it is less efficient and persistent than chemical insecticides. to bypass these limitations, we propose to combine the advantages of chemical and biological insecticides by producing bti in a medium supplemented with a chemical insecticide (ddt, deltamethrin, permethrin, propoxur or temephos). among the inv ... | 2013 | 23594143 |
| spaceflight-induced enhancement of 2-keto-l-gulonic acid production by a mixed culture of ketogulonigenium vulgare and bacillus thuringiensis. | two bacterial strains used for industrial production of 2-keto-l-gulonic acid (2-klg), ketogulonigenium vulgare 2 and bacillus thuringiensis 1514, were loaded onto the spacecraft shenzhou vii and exposed to space conditions for 68 h in an attempt to increase their fermentation productivities of 2-klg. an optimal combination of mutants b. thuringiensis 320 and k. vulgare 2194 (kb2194-320) was identified by systematically screening the ph and 2-klg production of 16 000 colonies. compared with the ... | 2013 | 23581457 |
| in silico cloning and annotation of genes involved in the digestion, detoxification and rna interference mechanism in the midgut of bactrocera dorsalis [hendel (diptera: tephritidae)]. | as the second largest organ in insects, the insect midgut is the major tissue involved in the digestion of food and detoxification of xenobiotics, such as insecticides, and the first barrier and target for oral rna interference (rnai). in this study, we performed a midgut-specific transcriptome analysis in the oriental fruit fly, bactrocera dorsalis, an economically important worldwide pest, with many populations showing high levels of insecticide resistance. using high-throughput sequencing, 52 ... | 2013 | 23577657 |
| genetically modified crops: detection strategies and biosafety issues. | genetically modified (gm) crops are increasingly gaining acceptance but concurrently consumers' concerns are also increasing. the introduction of bacillus thuringiensis (bt) genes into the plants has raised issues related to its risk assessment and biosafety. the international regulations and the codex guidelines regulate the biosafety requirements of the gm crops. in addition, these bodies synergize and harmonize the ethical issues related to the release and use of gm products. the labeling of ... | 2013 | 23566850 |
| activity of bacillus thuringiensis cyt1ba crystal protein against hymenopteran forest pests. | a crystal-spore suspension of ps201t6 was toxic to larvae of diprion similis (hymenoptera: diprionidae). toxicity was at least in part attributable to the cyt1ba crystal protein, as demonstrated by bioassays of solubilized protein produced by escherichia coli expressing ps201t6's cyt1ba gene. ps201t6 reduced survival and growth of d. similis in a 2-week field experiment. in laboratory bioassays, both toxin and parental strain affected acantholyda erythrocephala (pamphiliidae), pikonema alaskensi ... | 2013 | 23545068 |
| bt crops producing cry1ac, cry2ab and cry1f do not harm the green lacewing, chrysoperla rufilabris. | the biological control function provided by natural enemies is regarded as a protection goal that should not be harmed by the application of any new pest management tool. plants producing cry proteins from the bacterium, bacillus thuringiensis (bt), have become a major tactic for controlling pest lepidoptera on cotton and maize and risk assessment studies are needed to ensure they do not harm important natural enemies. however, using cry protein susceptible hosts as prey often compromises such s ... | 2013 | 23544126 |
| identification of a bacillus thuringiensis cry8da toxin-binding glucosidase from the adult japanese beetle, popillia japonica. | cry8da from bacillus thuringiensis galleriae sds-502 has insecticidal activity against both the larvae and adult japanese beetle (popillia japonica newman). the receptor determines the specificity of the insecticidal activity of cry proteins and hence, in order to reveal the mode of action of cry toxin, receptor identification is a necessary step. however, a receptor for cry8-type toxin has not been identified in the scarabaeidae family of insects. therefore, we aimed to identify the receptor of ... | 2013 | 23541518 |
| cloning and characterization of a novel cry8ab1 gene from bacillus thuringiensis strain b-jjx with specific toxicity to scarabaeid (coleoptera: scarabaeidae) larvae. | isolation of bacillus thuringiensis (bt) strain or its cry gene encoding insecticidal crystal protein (icp) with specific toxicity is of great importance to biological control of insect pests. in this study, by screening 66 strains of bt isolated from soil samples collected in shandong province, china, a new cry8-type gene from bt strain b-jjx was identified via pcr-rflp method. this novel gene, cry8ab1, was cloned from the bt strain b-jjx and expressed in an acrystalliferous mutant strain hd-73 ... | 2013 | 23541365 |
| effect of stacked insecticidal cry proteins from maize pollen on nurse bees (apis mellifera carnica) and their gut bacteria. | honey bee pollination is a key ecosystem service to nature and agriculture. however, biosafety research on genetically modified crops rarely considers effects on nurse bees from intact colonies, even though they receive and primarily process the largest amount of pollen. the objective of this study was to analyze the response of nurse bees and their gut bacteria to pollen from bt maize expressing three different insecticidal cry proteins (cry1a.105, cry2ab2, and cry3bb1). naturally cry proteins ... | 2013 | 23533634 |
| potential shortfall of pyramided transgenic cotton for insect resistance management. | to delay evolution of pest resistance to transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt), the "pyramid" strategy uses plants that produce two or more toxins that kill the same pest. in the united states, this strategy has been adopted widely, with two-toxin bt cotton replacing one-toxin bt cotton. although two-toxin plants are likely to be more durable than one-toxin plants, the extent of this advantage depends on several conditions. one key assumption favoring ... | 2013 | 23530245 |
| bacillus thuringiensis israelensis (bti) for the control of dengue vectors: systematic literature review. | to systematically review the literature on the effectiveness of bacillus thuringiensis israelensis (bti), when used as a single agent in the field, for the control of dengue vectors. | 2013 | 23527785 |
| draft genome sequence of bacillus thuringiensis strain dar 81934, which exhibits molluscicidal activity. | bacillus thuringiensis has been widely used as a biopesticide for a long time. its molluscicidal activity, however, is rarely realized. here, we report the genome sequence of b. thuringiensis strain dar 81934, a strain with molluscicidal activity against the pest snail cernuella virgata. | 2013 | 23516227 |
| complete genome sequence of bacillus thuringiensis subsp. thuringiensis strain is5056, an isolate highly toxic to trichoplusia ni. | the genome sequence of the entomopathogen bacillus thuringiensis subsp. thuringiensis strain is5056 was determined. the chromosome is composed of 5,491,935 bp. in addition, is5056 harbors 14 plasmids ranging from 6,880 to 328,151 bp, four of which contain nine insecticidal protein genes, cry1aa3, cry1ab21, cry1ba1, cry1ia14, cry2aa9, cry2ab1, vip1, vip2, and vip3aa10. | 2013 | 23516221 |
| complete genome sequence of bacillus thuringiensis subsp. kurstaki strain hd73. | bacillus thuringiensis is a gram-positive bacterium that produces intracellular protein crystals toxic to a wide variety of insect larvae. we report the complete genome sequence of bacillus thuringiensis subsp. kurstaki strain hd73 from the centre oilb (institut pasteur, france), which belongs to serotype 3ab and is toxic to lepidopteran larvae. | 2013 | 23516207 |
| constructing bacillus thuringiensis strain that co-expresses cry2aa and chitinase. | a triple recombineering technique was used with plasmid pht315 to produce phtec, a construct carrying chitinase and cry2aa genes from bacillus thuringiensis subsp. kurstaki 4.0718. transformation of wild-type b. thuringiensis strain hd73 and the acrystalliferous strain cry-b with phtec resulted in the recovery of recombinant strains that expressed cry2aa as cubic crystals in the cell pellet and soluble chitinase protein. the toxicity of hd73 (phtec) against helicoverpa armigera larvae increased ... | 2013 | 23515891 |
| cation-π interactions as lipid-specific anchors for phosphatidylinositol-specific phospholipase c. | amphitropic proteins, such as the virulence factor phosphatidylinositol-specific phospholipase c (pi-plc) from bacillus thuringiensis , often depend on lipid-specific recognition of target membranes. however, the recognition mechanisms for zwitterionic lipids, such as phosphatidylcholine, which is enriched in the outer leaflet of eukaryotic cells, are not well understood. a 500 ns long molecular dynamics simulation of pi-plc at the surface of a lipid bilayer revealed a strikingly high number of ... | 2013 | 23506313 |
| efficient genetic transformation of okra (abelmoschus esculentus (l.) moench) and generation of insect-resistant transgenic plants expressing the cry1ac gene. | agrobacterium -mediated transformation system for okra using embryos was devised and the transgenic bt plants showed resistance to the target pest, okra shoot, and fruit borer ( earias vittella ). okra is an important vegetable crop and progress in genetic improvement via genetic transformation has been impeded by its recalcitrant nature. in this paper, we describe a procedure using embryo explants for agrobacterium-mediated transformation and tissue culture-based plant regeneration for efficien ... | 2013 | 23504006 |
| enhancement of heavy metal phytoremediation by alnus firma with endophytic bacillus thuringiensis gdb-1. | phytoremediation shows potential for remediating mine tailing sites contaminated with heavy metals. our aim was to isolate, characterize, and assess the potential of endophytic bacteria to enhance growth and metal accumulation by the hyperaccumulator alnus firma. a bacterial strain isolated from roots of pinus sylvestris had the capacity to remove heavy metals from mine tailing and was identified as bacillus thuringiensis gdb-1 based on 16s ribosomal dna sequencing. gdb-1 exhibited plant growth- ... | 2013 | 23500429 |
| pest trade-offs in technology: reduced damage by caterpillars in bt cotton benefits aphids. | the rapid adoption of genetically engineered (ge) plants that express insecticidal cry proteins derived from bacillus thuringiensis (bt) has raised concerns about their potential impact on non-target organisms. this includes the possibility that non-target herbivores develop into pests. although studies have now reported increased populations of non-target herbivores in bt cotton, the underlying mechanisms are not fully understood. we propose that lack of herbivore-induced secondary metabolites ... | 2013 | 23486438 |
| bacterial chitin binding proteins show differential substrate binding and synergy with chitinases. | glycosyl hydrolase (gh) family 18 chitinases (chi) and family 33 chitin binding proteins (cbps) from bacillus thuringiensis serovar kurstaki (btchi and btcbp), b. licheniformis dsm13 (blichi and blicbp) and serratia proteamaculans 568 (spchib and spcbp21) were used to study the efficiency and synergistic action of btchi, blichi and spchib individually with btcbp, blicbp or spcbp21. chitinase assay revealed that only btchi and spchib showed synergism in hydrolysis of chitin, while there was no in ... | 2013 | 23480960 |
| a new enrichment method for isolation of bacillus thuringiensis from diverse sample types. | new or more efficient methodologies having different principles are needed, as one method could not be suitable for isolation of organisms from samples of diverse types and from various environments. in present investigation, growth kinetics study revealed a higher germination rate, a higher growth rate, and maximum sporulation of bacillus thuringiensis (bt) compared to other bacillus species. considering these facts, a simple and efficient enrichment method was devised which allowed propagation ... | 2013 | 23468005 |
| probing the fractal pattern and organization of bacillus thuringiensis bacteria colonies growing under different conditions using quantitative spectral light scattering polarimetry. | development of methods for quantification of cellular association and patterns in growing bacterial colony is of considerable current interest, not only to help understand multicellular behavior of a bacterial species but also to facilitate detection and identification of a bacterial species in a given space and under a given set of condition(s). we have explored quantitative spectral light scattering polarimetry for probing the morphological and structural changes taking place during colony for ... | 2013 | 23462968 |
| occurrence and larval movement of diatraea saccharalis (lepidoptera: crambidae) in seed mixes of non-bt and bt pyramid corn. | larval movement of target pest populations among bt and non-bt plants is a major concern in the use of a seed mixture refuge strategy for bt resistance management. in this study, occurrence and larval movement of the sugarcane borer, diatraea saccharalis (f.), were evaluated in four planting patterns of non-bt and bt plants containing genuity® smartstax(tm) traits in 2009-2011. the four planting patterns were: (1) a pure stand of 27 bt plants; (2) one non-bt plant in the center, surrounded by 26 ... | 2013 | 23456950 |
| expression of cry3a gene and its toxicity against asian gray weevil myllocerus undecimpustulatus undatus marshall (coleoptera: curculionidae). | coleopterans are the most damaging pests of many agricultural and forestry crops; there is an urgent need to develop effective biopesticides against these insects. enhancers of bt toxicity typify an opportunity to improve currently available commercial products into more effective control agents against diverse pests. a 1.9 kb dna fragment, pcr amplified from native isolates of bt using cry3a gene specific primers was cloned in expression vector pqe-80l and then used for transformation of escher ... | 2013 | 23456617 |
| characterization of the chitinase gene in bacillus thuringiensis mexican isolates. | the chitinase gene was molecularly characterized in five bacillus thuringiensis mexican isolates, mr10, mr11, mr21, mr33, and rn52. the proteins derived from these genes were tested for their chitinase activity using fluorogenic chitin derivatives. in order to verify if chitinase genes were functional, they were cloned, and enzymatic activity of recombinant chitinases was also tested. results indicated that enzymes exhibited endochitinase activity. the highest hydrolytic activity shown against t ... | 2013 | 23456349 |
| characterization of cry9da4, cry9eb2, and cry9ee1 genes from bacillus thuringiensis strain t03b001. | three cry9 genes, cry9da4, cry9eb2, and cry9ee1, were cloned from bacillus thuringiensis strain t03b001 using a high-resolution melting analysis method. all three cry9 genes were overexpressed in escherichia coli rosetta (de3), and the expressed products cry9eb2 and cry9ee1 were shown to be toxic to plutella xylostella and ostrinia furnacalis, but not to helicoverpa armigera or colaphellus bowringi. the bioassay of cry9eb2 and cry9ee1 against cry1ac-resistant p. xylostella strains indicated that ... | 2013 | 23455566 |
| risk assessment for helicoverpa zea (lepidoptera: noctuidae) resistance on dual-gene versus single-gene corn. | recent environmental protection agency (epa) decisions regarding resistance management in bt-cropping systems have prompted concern in some experts that dual-gene bt-corn (cryla.105 and cry2ab2 toxins) may result in more rapid selection for resistance in helicoverpa zea (boddie) than single-gene bacillus thuringiensis (bt)-corn (crylab toxin). the concern is that bt-toxin longevity could be significantly reduced with recent adoption of a natural refuge for dual-gene bt-cotton (crylac and cry2ab2 ... | 2013 | 23448055 |
| investigating alternatives to traditional insecticides: effectiveness of entomopathogenic fungi and bacillus thuringiensis against citrus thrips and avocado thrips (thysanoptera: thripidae). | citrus thrips, scirtothrips citri (moulton) (thysanoptera: thripidae), is a plant-feeding pest most widely recognized for causing damage to citrus (citrus spp. l. [rutaceae]) and mango (mangifera indica l. [anacardiaceae]) fruits. this insect has recently broadened its known host range to become a significant pest of california grown blueberries. avocado thrips, scirtothrips. perseae nakahara (thysanoptera: thripidae), is a recent, invasive pest of california avocados, persea americana mill. (la ... | 2013 | 23448016 |
| the effect of gamma sterilization on the insecticidal toxicity of engineered and conventional bacillus thuringiensis strains. | this study evaluates the effect of gamma radiation on the spore activity, toxicity, and crystal structures of two engineered bacillus thuringiensis (bt) strains, tnx and tny, and the reference bt strain hd-1. we attempted to identify dosages of cobalt-60 gamma radiation that would inactivate bt spores but not affect its toxicity. in the radiation dosage range of 10-15 kilogray, no viable spore formation and no significant reduction of the efficiency of bt against lepidopteran larvae were observe ... | 2013 | 23448012 |
| the atp-binding cassette transporter subfamily c member 2 in bombyx mori larvae is a functional receptor for cry toxins from bacillus thuringiensis. | bacillus thuringiensis is the most widely used biopesticide, and its cry toxin genes are essential transgenes for the generation of insect-resistant transgenic crops. recent reports have suggested that atp-binding cassette transporter subfamily c2 (abcc2) proteins are implicated in cry intoxication, and that a single amino acid insertion results in high levels of resistance to cry1 toxins. however, there is currently no available direct evidence of functional interactions between abcc2 and cry t ... | 2013 | 23432933 |
| [susceptibility of aedes aegypti (l.) strains from havana to a bacillus thuringiensis var. israelensis]. | the integration of chemical and biological methods is one of the strategies for the vector control, due to the existing environmental problems and the concerns of the community as a result of the synthetic organic insecticide actions. the bacterium called bacillus thuringiensis var. israelensis in liquid formulation has been widely used in the vector control programs in several countries and has shown high efficacy at lab in cuba. | 2013 | 23424808 |
| [influence of biotic factors on the efficacy of bacillus thuringiensis var. israelensis against aedes aegypti (diptera: culicidae)]. | bacillus thuringiensis h-14 has shown high efficacy on aedes aegypti larvae. but a number of factors could affect its effectiveness. knowing these factors is of vital importance for improving the application parameters in real conditions in order to guarantee the treatment's efficiency and to reduce environmental impact. | 2013 | 23424800 |
| further research on the biological function of inclusion bodies of anomala cuprea entomopoxvirus, with special reference to the effect on the insecticidal activity of a bacillus thuringiensis formulation. | entomopoxviruses (evs) form two types of inclusion body: spheroids, which contain virions, and spindles, which do not. the authors tested whether the spindles from a coleopteran ev, anomala cuprea ev (acev), enhanced the insecticidal activity of a commercial bacillus thuringiensis (bt) formulation and the susceptibility of scarabaeid pest species in japan to the virus's spheroids, to assess whether acev inclusion bodies are potential biological control agents for pest insects. | 2014 | 23424042 |
| insecticidal activity of vip3aa, vip3ad, vip3ae, and vip3af from bacillus thuringiensis against lepidopteran corn pests. | vip3aa, vip3ad, vip3ae, and vip3af proteins from bacillus thuringiensis were tested for their toxicity against spodoptera frugiperda and agrotis ipsilon. vip3ad was non-toxic to the two species. vip3ae and vip3af were significantly more toxic than vip3aa against s. frugiperda, both as protoxins and as toxins. against a. ipsilon, vip3ae protoxin was more toxic than vip3aa and vip3af protoxins. purification by metal-chelate affinity chromatography significantly affected vip3ae toxicity against the ... | 2013 | 23415860 |
| purification and characterization of the bacteriocin thuricin bn1 produced by bacillus thuringiensis subsp. kurstaki bn1 isolated from a hazelnut pest. | a novel bioactive molecule produced by bacillus thuringiensis subsp. kurstaki bn1 (bt-bn1), isolated from a common pest of hazelnut, balaninus nucum l. (coleoptera: curculionidae), was determined, purified, and characterized in this study. the bt-bn1 strain was investigated for antibacterial activity with an agar spot assay and well diffusion assay against b. cereus, b. weinhenstephenensis, l. monocytogenes, p. savastanoi, p. syringae, p. lemoignei, and many other b. thuringiensis strains. the p ... | 2013 | 23412058 |
| the metabolic regulation of sporulation and parasporal crystal formation in bacillus thuringiensis revealed by transcriptomics and proteomics. | bacillus thuringiensis is a well-known entomopathogenic bacterium used worldwide as an environmentally compatible biopesticide. during sporulation, b. thuringiensis accumulates a large number of parasporal crystals consisting of insecticidal crystal proteins (icps) that can account for nearly 20-30% of the cell's dry weight. however, the metabolic regulation mechanisms of icp synthesis remain to be elucidated. in this study, the combined efforts in transcriptomics and proteomics mainly uncovered ... | 2013 | 23408684 |
| complete genome sequence of bacillus thuringiensis strain 407 cry-. | bacillus thuringiensis is an insect pathogen that has been used widely as a biopesticide. here, we report the genome sequence of strain 407 cry-, which is used to study the genetic determinants of pathogenicity. the genome consists of a 5.5-mb chromosome and nine plasmids, including a novel 502-kb megaplasmid. | 2013 | 23405326 |
| complete genome sequence of bacillus thuringiensis bacteriophage bmbtp2. | bacillus thuringiensis is an insect pathogen which has been widely used for biocontrol. during b. thuringiensis fermentation, lysogenic bacteriophages cause severe losses of yield. here, we announce the complete genome sequence of a bacteriophage, bmbtp2, which is induced from b. thuringiensis strain ybt-1765, which may be helpful to clarify the mechanism involved in bacteriophage contamination. | 2013 | 23405296 |
| utilization of silkworm litter and pupal waste-an eco-friendly approach for mass production of bacillus thuringiensis. | the objective of the present study was to investigate the utilization of pupal waste and silkworm litter separately as production media for the mass cultivation of the potential biopesticide, bacillus thuringiensis (bt). bt is the most successful commercial biopesticide accounting for 90% of all biopesticides sold all over the world. biochemical analysis of the dry pupal waste revealed to be consisting of 4% carbohydrates, 44.9% proteins and 40% lipids. similarly the biochemical composition of d ... | 2013 | 23403062 |
| asian corn borer (acb) and non-acb pests in gm corn (zea mays l.) in the philippines. | the asian corn borer (acb), ostrinia furnacalis (guenée), has become the most damaging pest in corn in south-east asia. corn farmers in the philippines have incurred great yield losses in the past decades because of acb infestation. bacillus thuringiensis (bt) and bt herbicide-tolerant (btht) corns have been developed to reduce borer attacks worldwide. this study assessed the extent of acb and non-acb pest infestations in both gm and non-gm corn in isabela province, the philippines. specific aim ... | 2013 | 23401215 |
| high-level synthesis of endochitinase chia74 in escherichia coli k12 and its promising potential for use in biotechnology. | in the present study, we expressed the chia74 gene of bacillus thuringiensis in escherichia coli k12 and demonstrated that the active chia74 enzyme was produced at a high level in this strain. the chia74 enzymatic activity (in units per milliliter) was approximately 500 % greater in e. coli k12 when compared to that produced in e. coli dh5α. moreover, we showed that, when using our protocol, chia74 preparations obtained from recombinant e. coli k12 did not contain live bacteria, although transfo ... | 2013 | 23400505 |
| a differentially displayed mrna related to resistance to bacillus thuringiensis israelensis of aedes albopictus selected in vitro-activated cyt1aa6. | we compared the differential display of aedes albopictus cells, both resistant and susceptible to bacillus thuringiensis israelensis (bti), using differentially displayed reverse transcription polymerase chain reaction. we found 1 band about 200 base pairs long. after cloning and sequencing, the differentially expressed gene was similar to some partial messenger ribonucleic acid of ae. aegypti, culex quinquefasciatus, and anopheles gambiae, rather than ae. albopictus. this will be of some value ... | 2012 | 23393759 |
| influence of oxalic and malic acids in chickpea leaf exudates on the biological activity of cryiac towards helicoverpa armigera. | efforts are being made to express toxin genes from the bacterium, bacillus thuringiensis (bt) in chickpea for minimizing the losses due to the pod borer, helicoverpa armigera. however, there is an apprehension that acidic exudates in chickpea leaves may influence the protoxin-toxin conversion in the insect midgut, and thus, reduce the efficacy of bt toxins. therefore, we studied the influence of organic acids (oxalic acid and malic acid) present in the trichome exudates of chickpea on the biolog ... | 2013 | 23391855 |
| long-term survival of bacillus thuringiensis subsp. kurstaki in a field trial. | long-term survival of bacillus thuringiensis subsp. kurstaki dmu67r has been investigated in a field trial. an experimental cabbage plot was sprayed with dmu67r in 1993 and was allowed to lie fallow since then. the investigation reported here was carried out from 2001 to 2007 in a single square meter within the plot using a systematic randomized sampling approach. the bacterium survived at relative low densities in these 13 years after spraying. statistical analyses revealed that the overall den ... | 2013 | 23391227 |
| effect of vegetation on the presence and genetic diversity of bacillus thuringiensis in soil. | bacillus thuringiensis isolates were obtained from soil samples collected at different sites located in the same region but with different vegetation. the sites showed different frequencies of b. thuringiensis, depending on the type of vegetation. strains of b. thuringiensis were found to be less common in samples of riparian forest soil than in soil of other types of vegetation. the rate of occurrence of b. thuringiensis in the samples also varied according to the vegetation. these results show ... | 2013 | 23391226 |
| a phenylalanine clamp controls substrate specificity in the quorum-quenching metallo-γ-lactonase from bacillus thuringiensis. | autoinducer inactivator a (aiia) is a metal-dependent n-acyl homoserine lactone hydrolase that displays broad substrate specificity but shows a preference for substrates with long n-acyl substitutions. previously, crystal structures of aiia in complex with the ring-opened product n-hexanoyl-l-homoserine revealed binding interactions near the metal center but did not identify a binding pocket for the n-acyl chains of longer substrates. here we report the crystal structure of an aiia mutant, f107w ... | 2013 | 23387521 |
| [purification and physicochemical properties of bacillus thuringiensis imb b-7324 peptidase with elastolytic and fibrinolytic activity]. | the scheme of isolation and purification of bacillus thuringiensis imv b-7324 peptidase has been developed. this scheme includes ammonium sulfate precipitation and chromatography on neutral and charged tsk-gels. it was found that the enzyme hydrolyzes elastin and fibrin. the molecular weight is 26 kda. it was shown that the enzyme is an alkaline serine peptidase. the optimal ph of hydrolysis of elastin and fibrin were 9.0 and 10.0, respectively. the optimal temperature of elastin and fibrin hydr ... | 2015 | 23387266 |
| bacillus thuringiensis isolates from great nicobar islands. | bacillus thuringiensis (bt) strains were isolated from soil samples of great nicobar islands, one of the "hottest biodiversity hotspots," where no collection has been characterized previously. the 36 new bt isolates were obtained from 153 samples analyzed by crystal protein production with light/phase-contrast microscopy, determination of cry gene profile by sds-page, evaluation of toxicity against coleopteran, and lepidopteran insect pests, finally cloning and sequencing. majority of the isolat ... | 2013 | 23377491 |
| overexpression of polyphosphate kinase gene (ppk) increases bioinsecticide production by bacillus thuringiensis. | polyphosphate (polyp), synthesized by polyp kinase (ppk) using the terminal phosphate of atp as substrate, performs important functions in every living cell. the present work reports on the relationship between polyp metabolism and bioinsecticide production in bacillus thuringiensis subsp. israelensis (bti). the ppk gene of bti was cloned into vector pht315 and the effect of its overexpression on endotoxin production was determined. endotoxin production by the recombinant strain was found to be ... | 2013 | 23369305 |
| susceptibility and selectivity of cnaphalocrocis medinalis (lepidoptera: pyralidae) to different cry toxins. | effectiveness of four cry toxins (cry1ac, cry1aa, cry1ab, and cry1c) on cnaphalocrocis medinalis (guenée) (lepidoptera: pyralidae), collected from paddy fields in jiaxing, zhejiang province, china, was evaluated in the laboratory. bioassays showed that c. medinalis had different susceptibilities against four cry toxins. the lc50 values of cry1ac, cry1ab, cry1aa, and cry1c against c. medinalis were 0.405, 1.111, 1.939, and 1.246 microg/ml, respectively. furthermore, the mortality of c. medinalis ... | 2012 | 23356078 |
| impact of six transgenic bacillus thuringiensis rice lines on four nontarget thrips species attacking rice panicles in the paddy field. | as a key component of ecological risk assessments, nontarget effects of bacillus thuringiensis (bt) rice have been tested under laboratory and field conditions for various organisms. a 2-yr field experiment was conducted to observe the nontarget effects of six transgenic rice lines (expressing the cry1ab or fused protein of cry1ab and cry1ac) on four nontarget thrips species including frankliniella intonsa (trybom), f. tenuicornis (uzel), haplothrips aculeatus (f.), and h. tritici (kurd), as com ... | 2013 | 23339799 |
| application of box-behnken experimental design to optimize the extraction of insecticidal cry1ac from soil. | a validated method for analyzing cry proteins is a premise to study the fate and ecological effects of contaminants associated with genetically engineered bacillus thuringiensis crops. the current study has optimized the extraction method to analyze cry1ac protein in soil using a response surface methodology with a three-level-three-factor box-behnken experimental design (bbd). the optimum extraction conditions were at 21 °c and 630 rpm for 2 h. regression analysis showed a good fit of the exper ... | 2013 | 23327690 |
| laboratory assessment of the impacts of transgenic bt rice on the ecological fitness of the soil non-target arthropod, folsomia candida (collembola: isotomidae). | transgenic rice expressing bacillus thuringiensis (bt) endotoxins (bt rice) for pest control is considered an important solution to food security in china. however, tests for potential effects on non-target soil organisms are required for environmental risk assessment. the soil collembolan folsomia candida l. (collembola: isotomidae) is a potential non-target arthropod that is often used as a biological indicator in bio-safety assessments of transgenic crops. in the present study, the roots, ste ... | 2013 | 23322316 |
| electrogenerated chemiluminescence immunosensor for bacillus thuringiensis cry1ac based on fe3o4@au nanoparticles. | a highly sensitive electrochemiluminescence (ecl) immunosensor for cry1ac was fabricated. the primary antibody anti-cry1ac was immobilized onto core-shell structural fe(3)o(4)@au nanoparticles. the antigen and glucose-oxidase-labeled secondary antibody were then successively combined to form sandwich-type immunocomplexes through a specific interaction. the magnetic particles loaded with sandwich immune complexes were attracted to a magnet-controlled glass carbon electrode (gce) by an external ma ... | 2013 | 23317307 |
| cyt1aa from bacillus thuringiensis subsp. israelensis enhances mosquitocidal activity of b. thuringiensis subsp. kurstaki hd-1 against aedes aegypti but not culex quinquefasciatus. | the cyt1aa protein of bacillus thuringiensis subsp. israelensis is known to synergize mosquitocidal proteins of b. thuringiensis and bacillus sphaericus strains. cyt1aa is highly lipophilic, and after binding in vivo to the midgut microvillar membrane serves as a "receptor" for mosquitocidal cry proteins, which subsequently form cation channels that kill mosquito larvae. here we report that cyt1aa can serve a similar function for lepidopteran-specific cry proteins of b. thuringiensis in certain ... | 2013 | 23314373 |
| health effects of selected microbiological control agents. a 3-year follow-up study. | microbiological control agents (mbca) are widely used in greenhouses, replacing chemical pesticides. the presented study aims to describe health effects of exposure to three types commonly used: bacillus thuringiensis, verticillium lecanii, and trichoderma harzenianum covering seven different products in greenhouse workers with emphasis on sensitization and respiratory effects. | 2012 | 23311779 |
| [comparison of codon optimizations of cry1ah1 gene in rice]. | cry1ah1, one of holo-type cry genes, cloned in this laboratory from bacillus thuringiensis strain has been patented in china, and it encoded a protein with strong insecticidal activity against certain lepidopteran insect pests, such as chilo suppressalis. cry1ah1 gene is exhibiting good application prospects. in order to improve the expression level of cry1ah1 gene in rice, and investigate the effect of codon usage preference of gene expression, we designed five different optimized schemes for c ... | 2012 | 23311133 |
| new variants of lepidoptericidal toxin genes encoding bacillus thuringiensis vip3aa proteins. | bacillus thuringiensis is an entomopathogenic bacterium characterized by producing parasporal proteinaceous insecticidal crystal inclusions during sporulation. many strains are capable of also expressing other insecticidal proteins called vip during the vegetative growing phase. particularly, vip3a proteins have activity against certain lepidoptera species through a unique mechanism of action which emphasized their possible use in resistance management strategies against resistant pests. the aim ... | 2012 | 23307196 |
| parasporin 1ac2, a novel cytotoxic crystal protein isolated from bacillus thuringiensis b0462 strain. | two novel parasporin (ps) genes were cloned from bacillus thuringiensis b0462 strain. one was 100 % identical even in nucleotide sequence level with that of parasporin-1aa (ps1aa1) from b. thuringiensis a1190 strain. the other (ps1ac2) showed significant homology (99 % identity) to that of ps1ac1 from b. thuringiensis 87-29 strain. the 15 kda (s(113)-r(250)) and 60 kda (i(251)-s(777)) fragments consisting of an active form of ps1ac2 were expressed as his-tag fusion. upon purification under denat ... | 2013 | 23306354 |
| sex differences in host defence interfere with parasite-mediated selection for outcrossing during host-parasite coevolution. | the red queen hypothesis proposes that coevolving parasites select for outcrossing in the host. outcrossing relies on males, which often show lower immune investment due to, for example, sexual selection. here, we demonstrate that such sex differences in immunity interfere with parasite-mediated selection for outcrossing. two independent coevolution experiments with caenorhabditis elegans and its microparasite bacillus thuringiensis produced decreased yet stable frequencies of outcrossing male h ... | 2013 | 23301667 |
| non-recessive bt toxin resistance conferred by an intracellular cadherin mutation in field-selected populations of cotton bollworm. | transgenic crops producing bacillus thuringiensis (bt) toxins have been planted widely to control insect pests, yet evolution of resistance by the pests can reduce the benefits of this approach. recessive mutations in the extracellular domain of toxin-binding cadherin proteins that confer resistance to bt toxin cry1ac by disrupting toxin binding have been reported previously in three major lepidopteran pests, including the cotton bollworm, helicoverpa armigera. here we report a novel allele from ... | 2012 | 23285292 |
| greenhouse-selected resistance to cry3bb1-producing corn in three western corn rootworm populations. | transgenic corn producing the bacillus thuringiensis (bt) toxin cry3bb1 has been useful for controlling western corn rootworm, diabrotica virgifera virgifera leconte, one of the most economically important crop pests in the united states. however, rapid evolution of resistance by this beetle to bt corn producing cry3bb1 has been reported previously from the laboratory, greenhouse, and field. here we selected in the greenhouse for resistance to cry3bb1 corn in three colonies of wcr derived from k ... | 2012 | 23284656 |
| ochratoxin a management in vineyards by lobesia botrana biocontrol. | grape berries attacked by lobesia botrana larvae are more easily infected by aspergillus section nigri (black aspergilli) ochratoxigenic species. two-year field trials were carried out in apulia (italy) to evaluate a bioinsecticide control strategy against l. botrana and the indirect effect on reducing ochratoxin a (ota) contamination in vineyards. a commercial bacillus thuringiensis formulate and an experimental beauveria bassiana (item-1559) formulate were tested in two vineyards cultivated wi ... | 2013 | 23282670 |
| affinity maturation of cry1aa toxin to the bombyx mori cadherin-like receptor by directed evolution. | improvement of the activity and insecticidal spectrum of cloned cry toxins of bacillus thuringiensis should allow for their wider application as biopesticides and a gene source for gene-modified crops. the insecticidal activity of cry toxins depends on their binding to the receptor. therefore, as a model, we aimed to generate improved binding affinity mutant toxins against bombyx mori cadherin-like receptor (btr175) using methods of directed evolution with the expectation of insecticidal activit ... | 2013 | 23247992 |
| mortality and repellent effects of microbial pathogens on coptotermes formosanus (isoptera: rhinotermitidae). | two entomopathogenic fungi, isaria fumosorosea and metarhizium anisopliae, and one bacterium, bacillus thuringiensis, were tested for their ability to cause mortality of formosan subterranean termites (fst), coptotermes formosanus (shiraki), after liquid exposure, and for their lack of propensity to repel fst. | 2012 | 23241169 |
| [activity of four cry gene promoters in spoiiid mutant of bacillus thuringiensis]. | we studied the influence of spoiiid gene deletion on the activity of cry1ac, cry3a, cry4a and cry8e gene promoters in bacillus thuringiensis and compared the activity among these promoters in spoiiid mutant (hd-delta spoiiid). | 2012 | 23236841 |
| effects of cry1ab transgenic maize on lifecycle and biomarker responses of the earthworm, eisenia andrei. | a 28-day study was conducted to determine the effects of the bacillus thuringiensis cry1ab toxin on the earthworm eisenia andrei. previously, investigations have been limited to life-cycle level effects of this protein on earthworms, and mostly on e. fetida. in this study several endpoints were compared which included biomass changes, cocoon production, hatching success, a cellular metal-stress biomarker (neutral red retention time; nrrt) and potential genotoxic effects in terms of randomly ampl ... | 2012 | 23235452 |
| agcad2 cadherin in anopheles gambiae larvae is a putative receptor of cry11ba toxin of bacillus thuringiensis subsp. jegathesan. | in an effort to study the mode of action of cry11ba, we identified toxin binding proteins in anopheles gambiae larval midgut and investigated their receptor roles. previously, an aminopeptidase (agapn2) and an alkaline phosphatase (agalp1) were identified as receptors for cry11ba toxin in a. gambiae. however, an a. gambiae cadherin (agcad1) that bound cry11ba with low affinity (k(d) = 766 nm) did not support a receptor role of agcad1 for cry11ba. here, we studied a second a. gambiae cadherin (ag ... | 2013 | 23231770 |
| cloning, characterization, and expression of a new cry1ab gene from dor bt-1, an indigenous isolate of bacillus thuringiensis. | a new cry1ab gene was cloned from the promising local isolate, dor bt-1, a bacillus thuringiensis strain isolated from castor semilooper (achaea janata l.) cadavers from castor bean (ricinus communis l.) field. the nucleotide sequence of the cloned cry1ab gene indicated that the open reading frame consisted of 3,465 bases encoding a protein of 1,155 amino acid residues with an estimated molecular weight of 130 kda. homology comparisons revealed that the deduced amino acid sequence of cry1ab had ... | 2013 | 23224937 |
| bacillus thuringiensis cry1ia10 and vip3aa protein interactions and their toxicity in spodoptera spp. (lepidoptera). | the polyphagous pests belonging to the genus spodoptera are considered to be among the most important causes of damage and are widely distributed throughout the americas'. due to the extensive use of genetically modified plants containing bacillus thuringiensis genes that code for insecticidal proteins, resistant insects may arise. to prevent the development of resistance, pyramided plants, which express multiple insecticidal proteins that act through distinct mode of actions, can be used. this ... | 2013 | 23220241 |
| histopathological effects and determination of the putative receptor of bacillus thuringiensis cry1da toxin in spodoptera littoralis midgut. | bacillus thuringiensis subsp. aizawai strain hd133, known by its effectiveness against spodoptera species, produces many insecticidal proteins including cry1ab, cry1ca and cry1da. in the present study, the insecticidal activity of cry1da against spodoptera littoralis was investigated. it showed toxicity with an lc(50) of 224.4 ng/cm(2) with 95% confidence limits of (178.61-270.19) and an lc(90) of 467.77 ng/cm(2) with 95% confidence limits of (392.89-542.65). the midgut histopathology of cry1da ... | 2013 | 23220238 |
| complete genome sequence of bacillus thuringiensis serovar sichuansis strain mc28. | bacillus thuringiensis is an important microbial insecticide used in the control of agricultural pests. here we report the finished, annotated genome sequence of bacillus thuringiensis serovar sichuansis strain mc28, which can form parasporal crystals consisting of cry4cc1, cry30fa1, cry53ab1, cry54aa1, cry54ab1, cry68aa1, cry69aa1, cry69aa2, cry70ba1, cyt1da1, and cyt2aa3. it is also highly toxic to lepidopterous and dipterous insects. | 2012 | 23209229 |
| development and validation of a confirmative lc-ms/ms method for the determination of ß-exotoxin thuringiensin in plant protection products and selected greenhouse crops. | bacterial products based on bacillus thuringiensis are registered in many countries as plant protection products (ppps) and are widely used as insecticides and nematocides. however, certain b. thuringiensis strains produce harmful toxins and are therefore not allowed to be used as ppps. the serotype b. thuringiensis thuringiensis produces the beta-exotoxin thuringiensin (ßet) which is considered to be toxic for almost all forms of life including humans (who 1999). the use of a non-registered ppp ... | 2013 | 23208288 |
| molecular characterization and genetic diversity of insecticidal crystal protein genes in native bacillus thuringiensis isolates. | the western ghats of karnataka natural ecosystem are among the most diverse and is one of the eight hottest hotspots of biological diversity in the world, that runs along the western part of india through four states including karnataka. bacillus thuringiensis (bt) strains were isolated from soils of western ghats of karnataka and characterized by molecular and analytical methods as a result of which 28 new bt-like isolates were identified. bt strains were isolated from soil samples using sodium ... | 2013 | 23207696 |
| lengthening of insect development on bt zone results in adult emergence asynchrony: does it influence the effectiveness of the high dose/refuge zone strategy? | the “high dose/refuge” strategy (hd/r) is the currently recommended insect resistance management strategy (irm) to limit resistance development to bacillus thuringiensis (bt) plants. this strategy requires planting a “refuge zone” composed of non-bt plants suitable for the target insect and in close proximity to a “bt zone” expressing a high toxin concentration. one of the main assumptions is that enough susceptible adults mate with resistant insects. however, ... | 2012 | 23202319 |
| increase in larval gut proteolytic activities and bti resistance in the dengue fever mosquito. | the bioinsecticide bacillus thuringiensis var. israelensis (bti) is increasingly used worldwide for mosquito control. although no established resistance to bti has been described in the field so far, a resistant aedes aegypti strain (litox strain) was selected in the laboratory using field-collected leaf litter containing bti toxins. this selected strain exhibits a moderate resistance level to bti, but a high resistance level to individual cry toxins. as bti contains four different toxins, gener ... | 2013 | 23192850 |
| current status of genetic engineering in cotton (gossypium hirsutum l): an assessment. | cotton is considered as the foremost commercially important fiber crop and is deemed as the backbone of the textile industry. the productivity of cotton crop, worldwide, is severely hampered by the occurrence of pests, weeds, pathogens apart from various environmental factors. several beneficial agronomic traits, viz., early maturity, improved fiber quality, heat tolerance, etc. have been successfully incorporated into cotton varieties employing conventional hybridization and mutation breeding. ... | 2014 | 23190258 |
| effects of oral bt-maize (mon810) exposure on growth and health parameters in normal and sensitised atlantic salmon, salmo salar l. | responses to gm maize bt-maize, mon810) expressing cry1ab protein from the soil bacterium bacillus thuringiensis (bt) in diets for both normal and immune-sensitised (with soyabean meal (sbm)-induced enteropathy) post-smolt atlantic salmon were investigated following 33 and 97 d of exposure. triplicate tanks of salmon were fed one of four diets, all containing 20% whole-kernel meal maize, either bt-maize or its near-isogenic maternal line, without or with 15% extracted sbm inclusion. the fish fed ... | 2013 | 23182224 |
| eco-physiological response of two marine bivalves to acute exposition to commercial bt-based pesticide. | microbial products based on the entomopathogenic bacterium bacillus thuringiensis (bt) are among the most common biopesticides used worldwide to suppress insect pests in forests, horticulture and agricultural crops. some of the effects of commercial bt have been recorded for terrestrial and freshwater non-target organisms but little research is available on marine fauna. nevertheless, due to the contiguity of agro-ecosystems and coastal habitats, marine fauna may be highly influenced by this con ... | 2013 | 23168358 |
| effectiveness of the high dose/refuge strategy for managing pest resistance to bacillus thuringiensis (bt) plants expressing one or two toxins. | to delay resistance development to bacillus thuringiensis (bt) plants expressing their own insecticide, the application of the insect resistance management strategy called "high dose/refuge strategy" (hd/r) is recommended by the us environmental protection agency (us epa). this strategy was developed for bt plants expressing one toxin. presently, however, new bt plants that simultaneously express two toxins are on the market. we used a mathematical model to evaluate the efficiency of the hd/r st ... | 2012 | 23162699 |
| distribution and diversity analysis of bacillus thuringiensis cry genes in different soil types and geographical regions of india. | molecular characterization of 117 bacillus thuringiensis (bt) isolates from various geographical locations was previously done by pcr amplification of cry genes. in present investigation, diversity of cry genes from different soil types and climatic environments was studied using rarefaction method. presence of cry1, cry2, cry3, 7, 8, cry4, cry5, 12, 14, 21, cry11, cry13 and cyt1 genes from bt strains isolated from various regions of india was determined by pcr amplification. a varied distributi ... | 2013 | 23160085 |