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delivery of intrahemocoelic peptides for insect pest management.the extensive use of chemical insecticides for insect pest management has resulted in insecticide resistance now being recorded in >500 species of insects and mites. although gut-active toxins such as those derived from bacillus thuringiensis (bt) have been successfully used for insect pest management, a diverse range of insect-specific insecticidal peptides remains an untapped resource for pest management efforts. these toxins act within the insect hemocoel (body cavity) and hence require a del ...201424331760
complete genome sequence of bacillus thuringiensis ybt-1518, a typical strain with high toxicity to nematodes.bacillus thuringiensis is a ubiquitous spore-forming bacterium and has been widely used as a biopesticide for controlling agricultural insects by the production of insecticidal crystal proteins (icps). b. thuringiensis ybt-1518 displays effective toxicity to nematodes. this strain harbors three nematicidal crystal protein genes, including cry55aa1, cry6aa2 and cry5ba2, and also contains multiple potential virulence factors. here, we report the complete genome sequence of b. thuringiensis ybt-151 ...201424333130
differential activity of autochthonous bacteria in controlling drought stress in native lavandula and salvia plants species under drought conditions in natural arid soil.the effectiveness of autochthonous plant growth-promoting rhizobacteria was studied in lavandula dentata and salvia officinalis growing in a natural arid mediterranean soil under drought conditions. these bacteria identified as bacillus megaterium (bm), enterobacter sp. (e), bacillus thuringiensis (bt), and bacillus sp. (bsp). each bacteria has different potential to meliorate water limitation and alleviating drought stress in these two plant species. b. thuringiensis promoted growth and drought ...201424337805
bacillus thuringiensis as a surrogate for bacillus anthracis in aerosol research.characterization of candidate surrogate spores prior to experimental use is critical to confirm that the surrogate characteristics are as closely similar as possible to those of the pathogenic agent of interest. this review compares the physical properties inherent to spores of bacillus anthracis (ba) and bacillus thuringiensis (bt) that impact their movement in air and interaction with surfaces, including size, shape, density, surface morphology, structure and hydrophobicity. also evaluated is ...201424338558
bacillus thuringiensis poisoning related acute transverse myelitis. 201324340786
dermal toxicity, eye and dermal irritation and skin sensitization evaluation of a new formulation of bacillus thuringiensis var israelensis sh-14.bacillus thuringiensis (bt) is the best known and most widely used of all pesticidal microbes. the aim of this study was to assess the toxicity of a new formulation of bacillus thuringiensis var israelensis sh-14 in rats through acute dermal toxicity, dermal and eye irritation experiments. the acute dermal toxicity and dermal and eye irritation studies were performed using rabbits according to the united states environmental protection agency guidelines 885.3100, 870.2500 and 870.2500, respectiv ...201424342232
mechanism of killing of spores of bacillus anthracis in a high-temperature gas environment, and analysis of dna damage generated by various decontamination treatments of spores of bacillus anthracis, bacillus subtilis and bacillus thuringiensis.to determine how hydrated bacillus anthracis spores are killed in a high-temperature gas environment (htge), and how spores of several bacillus species including b. anthracis are killed by uv radiation, dry heat, wet heat and desiccation.201424344920
synthetic fusion-protein containing domains of bt cry1ac and allium sativum lectin (asal) conferred enhanced insecticidal activity against major lepidopteran pests.different transgenic crop plants, developed with δ-endotoxins of bacillus thuringiensis (bt) and mannose-specific plant lectins, exhibited significant protection against chewing and sucking insects. in the present study, a synthetic gene (cry-asal) encoding the fusion-protein having 488 amino acids, comprising di and dii domains from bt cry1ac and allium sativum agglutinin (asal), was cloned and expressed in escherichia coli. ligand blot analysis disclosed that the fusion-protein could bind to m ...201424355805
molecular characterization of bacillus thuringiensis using rep-pcr.the genetic divergence of 65 strains of bacillus thuringiensis (bt) was determined using rep-pcr. based on the repetitive sequences the box primer was the most informative with 26 fragments, followed by eric (19) and rep (10), generating a total of 55 fragments. the dendogram shows that ten groups were formed when 45% was the average distance of the population: group 1 with 41,5% of the isolates, 33,8% of the isolates were distributed in other groups and 24,6% did not formed distinct group. 53,2 ...201324363981
pre-feeding of a glycolipid binding protein lec-8 from caenorhabditis elegans revealed enhanced tolerance to cry1ac toxin in helicoverpa armigera.crystal toxins from bacillus thuringiensis bind to glycolipids and glycoproteins using two different lectin domains in the toxin protein. our previous observations suggested that the sequestration of crystal toxin depends on the functional interaction of a toxin lectin with glycolipids. given the finding that competition of a galectin lec-8 with cry5b for binding to glycolipids resulting in reduced bt toxicity in nematode, it is interesting to explore the role of lec-8 in insects. here, we repor ...201224371572
genotoxic evaluation in oreochromis niloticus (fish: characidae) of recombinant spore-crystal complexes cry1ia, cry10aa and cry1ba6 from bacillus thuringiensis.bioinsecticides from bacillus thuringiensis (bt) are widely used around the world in biological control against larval stages of many insect species. bt has been considered a biopesticide that is highly specific to different orders of insects, non-polluting and harmless to humans and other vertebrates, thus becoming a viable alternative for combating agricultural pests and insect vectors of diseases. the family of bt δ-endotoxins are crystal-protein inclusions showing toxicity to insects' midgut ...201424374720
improved insecticidal toxicity by fusing cry1ac of bacillus thuringiensis with av3 of anemonia viridis.av3, a neurotoxin of anemonia viridis, is toxic to crustaceans and cockroaches but inactive in mammals. in the present study, av3 was expressed in escherichia coli origami b (de3) and purified by reversed-phase liquid chromatography. the purified av3 was injected into the hemocoel of helicoverpa armigera, rendering the worm paralyzed. then, av3 was expressed alone or fusion expressed with the cry1ac in acrystalliferous strain cry(-)b of bacillus thuringiensis. the shape of cry1ac was changed by ...201424375189
antibacterial activity of elephant garlic and its effect against u2os human osteosarcoma cells.the present study was designed to investigate the antibacterial function and pharmacological effect of elephant garlic (allium ampeloprasum var. ampeloprasum) on u2os human osteosarcoma cells.201324379966
development of a high efficient "dual bt-plus" insecticide using a primary form of an entomopathogenic bacterium, xenorhabdus nematophila.a phase variation has been reported in an entomopathogenic bacterium, xenorhabdus nematophila. compared with a wild-type primary form, a secondary form usually loses several physiological and biochemical characters. this study showed that the phase variation of x. nematophila caused a significant alteration in its immunosuppressive activity and subsequent entomopathogenicity. a secondary form of x. nematophila was detected in laboratory colonies and exhibited significant differences in dye absor ...201424394195
hexamerin a novel protein associated with bacillus sphaericus resistance in culex quinquefasciatus.bacterial insecticides like, bacillus sphaericus and bacillus thuringiensis serovar israelensis, have been used for the control of nuisance and vector mosquitoes for more than two decades. for many years, it was assumed that the use of microbial larvicides based on b. sphaericus would not lead to resistance in mosquitoes. however, recent reports have shown that b. sphaericus toxins are not free from this problem. therefore, the resistance of mosquito populations to be will seriously threaten the ...201424395693
persistence and recycling of bioinsecticidal bacillus thuringiensis subsp. israelensis spores in contrasting environments: evidence from field monitoring and laboratory experiments.sprays of commercial preparations of the bacterium bacillus thuringiensis subsp. israelensis are widely used for the control of mosquito larvae. despite an abundant literature on b. thuringiensis subsp. israelensis field efficiency on mosquito control, few studies have evaluated the fate of spores in the environment after treatments. in the present article, two complementary experiments were conducted to study the effect of different parameters on b. thuringiensis subsp. israelensis persistence ...201424402370
coexpression of the silent cry2ab27 together with cry1 genes in bacillus thuringiensis subsp. aizawai sp41 leads to formation of amorphous crystal toxin and enhanced toxicity against helicoverpa armigera.the unexpressed cry2ab27 gene of bacillus thuringiensis subsp. aizawai sp41 (sp41) consists of a single open reading frame (orf) of 1902bp encoding for 634 amino acid residues. the cry2ab27 gene appears to be silent due to the lack of promoter and terminator sequences. in this study we fused the cry2ab27 orf with the cry1ab promoter (500bp) and the terminator (300bp) in vector pht304-18z in order to drive the expression of cry2ab27 in both sp41 and an acrystaliferous, b. thuringiensis subsp. thu ...201424412546
growth, sporulation and toxin production bybacillus thuringiensis subsp.israelensis andb. sphaericus in media based on mustard-seed meal.bacillus thuringiensis subsp.israelensis andb. sphaericus strains 2362 and 1593 were grown in media based on defatted mustard-seed meal (msm). the meal contains 40% (w/w) protein, with glutamic acid and arginine as the major amino acids. the toxic potencies of the final bacterial powders towardsculex pipens quinquefasciatus say, compared with those of the respective international reference standards, were 46% forb. thuringiensis subsp.israelensis, 62% forb. sphaericus 2362 and 88% forb. sphaeric ...199524414503
bacillus thuringiensis: ecology, the significance of natural genetic modification, and regulation.legislation and regulation in respect of genetically modified microorganisms must be based on rick-assessment principles rather than on the current european concept of pathogenicity, which is a measure of hazard. natural genetic modification has commerical attractions where the processes can be exempted from regulation. bacillus thuringiensis is used to illustrate this in the context of the european directives and uk regulation.199524414894
production of thuringiensin from bacillus thuringiensis using a net-draft-tube, modified airlift reactor.a net-draft-tube, modified airlift reactor and a stirred-tank reactor were used for thuringiensin production by bacillus thuringiensis subsp. darmstadiensis growing with various concentrations of molasses. the optimum concentration of molasses for thuringiensin production in both reactors was 15 g/l. there was a 6 h delay in sporulation in the modified airlift reactor compared with that in the stirred-tank reactor. thuringiensin yield in the modified airlift reactor (2.2 g/l) was consequently hi ...199624415084
selection of rhizosphere-competent pseudomonas strains as biocontrol agents in tropical soils.pseudomonas strains were isolated from the rhizosphere of maize grown in yellow-red latosol from rio de janeiro, brazil, to serve as a delivery system for heterologous genes and for risk assessment studies in tropical soils. selected strains were modified by insertion of the cryivb gene from bacillus thuringiensis and tested for pathogenicity gene expression against larvae of a susceptible model species, anopheles aquasalis. modified strains br8 and br12 showed similar survival performance to th ...199624415420
recoverability of heat-injured bacillus spores by lysozyme and edta or alkaline thioglycollate.the d95°c value of bacillus thuringiensis spores plated in the presence of lysozyme increased from 3.0 min to 3.6 min by post-treatment of heat-injured spores with 50mm edta. in the case of bacillus alvei and bacillus polymyxa spores d-values decreased from 4.9 to 4.3 min and from 4.7 to 4.1 min respectively. post-treatment of heat-injured spores treated with alkaline thioglycollate increased d95°c values of bacillus alvei from 4.2 to 5.3 min, b. thuringiensis 3.6 to 4.7 min, and bacillus polymy ...199624415421
algae in mosquito breeding sites and the effectiveness of the mosquito larvicide bacillus thuringiensis h-14.the presence of cyanobacteria generally decreased the effectiveness of bacillus thuringiensis h-14 (bti) as a mosquito larvicide. the effect was more pronounced when the mosquito larvae were exposed to bti in the presence of several cyanobacterial strains. no synergistic or antagonistic effect between the δ-endotoxin from bti and the hepatotoxin from cyanobacteria was seen. neurotoxic cyanobacterial strains caused very fast paralysis in mosquito larvae; the decreases in the effectiveness of bti ...199324419936
distribution of bacillus thuringiensis strains in southern sweden.bacillus thuringiensis strains were found to be naturally present in the soils of southern sweden, being isolated from nine out of 12 sites examined. forest soil samples were more rich in b. thuringiensis strains than soil samples collected from cultivated areas. a wide diversity of b. thuringiensis strains, representing different biochemical groups, was isolated; samples from aspö and fogdö regions showed the highest degree of diversity.199424420885
studies on bacillus thuringiensis strains isolated from swedish soils: insect toxicity and production of b. cereus-diarrhoeal-type enterotoxin.at moderate concentration, 23 of 40 strains of bacillus thuringiensis isolated from sweden were toxic to trichoplusia ni and five were toxic to aedes aegypti. five of the strains were toxic to diabrotica undecimpunctata at high concentration, two were toxic to heliothis virescens at low concentration and five produced thuringiensin (formerly called β-exotoxin). no strain was toxic towards the beet armyworm spodoptera exigua at low concentration. twenty-three of the strains produced a b. cereus-d ...199424421086
studies on bacillus thuringiensis h-14 strains isolated in egypt-iv. characterization of fermentation conditions for δ-endotoxin production.fermentation media formulated from inexpensive locally available ingredients, namely soya meal, proflo (a partially defatted cooked cottonseed fiour) and molasses, were assessed for growth, sporulation and δ-endotoxin production, by a mosquito-toxic strain of bacillus thuringlensis h-14 locally isolated in egypt, using an 8 i working volume fermenter. the insecticidal activity was assayed against culex piplens. good growth and sporulation were obtained with all the tested medium combinations, bu ...199124424937
studies on bacillus thuringiensis h-14 strains isolated in egypt-v. composition and toxicity of the mosquitocidal parasporal inclusions.parasporal inclusions of bacillus thuringlensis h-14 strains m1 and s128 were characterized by solubilization, electron microscopy, polyacrylamide gel electrophoresis, amino acid analysis and insecticidal activity. inclusions of both strains are composed largely of protein with 8 to 9% carbohydrate. amino acid analysis of the purlfied inclusions revealed that the two strains produce inclusions that are closely related to each other but significantly different from lepidopteran-toxic b. thuringie ...199124424938
spreading of bacillus thuringiensis var. israelensis over the water surface by a monolayer carrier.the self-spreading properties of monolayers, acting as carriers for bacillus thuringlensis var. israelensis, were examined in the laboratory. drops of mixtures of 0.5 to 5% b. thuringlensis in a liquid monolayer were placed at one end of a narrow static water course, 2 m long. in less than 2 min, a single layer of molecules spread over the water surface and deposited enough b. thuringiensis over the whole 2 m to kill test mosquito larvae in 24 h. the monolayer alone did not kill larvae in 24 h b ...199124425021
bacillus thuringiensis growth, sporulation and δ-endotoxin production in oxygen limited and non-limited cultures.the production of crystals and spores ofbacillus thuringiensis var.israelensis was studied under different aeration conditions. the results with 4 l batch cultures showed that for o2 non-limited, cultures cell yield, toxin production and spore count were constant for all oxygen transfer rates (otr). under o2 limitation, °-endotoxin concentrations and spore counts were lower than those obtained in non-limited cultures. in addition, δ-endotoxin yields diminished under o2 limitation, suggesting tha ...199224425483
microbial dynamics and diversity of bacillus thuringiensis in textile effluent polluted and non-polluted rice field soils of orissa, india.microbial diversity was assessed in the soils of non-polluted rice fields of central rice research institute and choudwar, and textile effluent contaminated (about 30 years) rice fields of choudwar about 4 years after cessation of pollution. the soils contained 0.62-1.01 % organic c and 0.07-0.12 % total n, and measured 6.18-8.24 ph and 0.6-2.68 ms/cm eh which were more in the polluted choudwar soil. the microbial populations (×10(6) cfu/g soil) in the soils were: heterotrophs 1.21-10.9, spore f ...201324426074
production of polyhydroxyalkanoate co-polymer by bacillus thuringiensis.integrative processes for the production of bioenergy and biopolymers are gaining importance in recent years as alternatives to fossil fuels and synthetic plastics. in the present study, bacillus thuringiensis strain egu45 has been used to generate hydrogen (h2), polyhydroxybutyrate (phb) and new co-polymers (np). under batch culture conditions with 250 ml synthetic media, b. thuringiensis egu45 produced up to 0.58 mol h2/mol of glucose. effluent from the h2 production stage was incubated under ...201324426082
insilico structural 3d modelling of novel cry1ib9 and cry3a toxins from local isolates of bacillus thuringiensis.three-dimensional (3d) models for the 79.2 kda activated cry1ib9 and 77.4 kda activated cry3a δ-endotoxins from bacillus thuringiensis (bt) native isolates that are specifically toxic to coleopteran insect pests were constructed by utilizing homology modeling online tool. evidences presented here, based on the identification of structural equivalent residues of cry1ib9 and cry3a toxin through homology modelling indicate that, they share a common bt toxin tridimensional structure. the main differ ...201424426173
occurrence of bacillus thuringiensis and their phages in yemen soil.bacillus thuringiensis (bt) isolates were found in all samples of soil in nine governorates of yemen. from 384 isolates of bacillus recovered from these soil samples after acetate selection, 104 isolates (27.1 %) were bt. five isolates of bt were selected and insecticidal activity was tested against culex pipiens, callosobruchus maculatus and spodoptera littoralis. the bt isolate yh18 gave toxicity to all tested insects larvae. this study extended to isolate phages active against the selected bt ...201324426317
new bacillus thuringiensis toxin combinations for biological control of lepidopteran larvae.cyt1aa from bacillus thuringiensis israelensis is known by its synergistical activity with b. thuringiensis and bacillus sphaericus toxins. it is able to improve dipteran specific toxins activity and can prevent or overcome larval resistance to those proteins. the objective of the current study was to investigate the possible improvement of larvicidal activity of b. thuringiensis kurstaki expressing heterogeneous proteins cyt1a and p20. cyt1a98 and p20 genes encoding the cytolytic protein (cyt1a ...201424444881
bacillus thuringiensis cry6a exhibits nematicidal activity to caenorhabditis elegans bre mutants and synergistic activity with cry5b to c. elegans.the group of nematicidal crystal protein cry6a shares very low identity and exhibits different structure with cry5b, another well-studied group of nematicidal crystal protein produced by bacillus thuringiensis. in this study, we assayed the susceptibility of bre mutants (caenorhabditis elegans with resistance to cry5b) to cry6aa2 and examined the synergistic activity between cry6aa2 and cry5ba2. our results show that all bre mutants are susceptible to cry6aa2 on the lethal activity, growth inhib ...201424450432
nisin a extends the shelf life of high-fat chilled dairy dessert, a milk-based pudding.the aims of this study were to evaluate the effectiveness of nisin a to control the growth of spore-forming bacteria, bacillus and paenibacillus, in chilled high-fat, milk pudding and to reduce heat treatment to improve aroma and flavour.201424450783
activation of map kinase pathways in galleria mellonella infected with bacillus thuringiensis.we followed changes in the level of phospho-map kinases in the greater wax moth galleria mellonella after infection with bacillus thuringiensis. we observed an enhanced level of phosphorylated p38 and jnk in fat bodies of the infected larvae. in hemocytes, injection of b. thuringiensis caused the highest increase in phospho-jnk, however, all pathways were activated after aseptic injection. we report that galleria mellonella larvae exposed to heat shock before infection showed an enhanced level o ...201424455757
bacillus thuringiensis cry1a toxins are versatile proteins with multiple modes of action: two distinct pre-pores are involved in toxicity.cry proteins from bacillus thuringiensis are insecticidal pfts (pore-forming toxins). in the present study, we show that two distinct functional pre-pores of cry1ab are formed after binding of the protoxin or the protease-activated toxin to the cadherin receptor, but before membrane insertion. both pre-pores actively induce pore formation, although with different characteristics, and contribute to the insecticidal activity. we also analysed the oligomerization of the mutant cry1abmod protein. th ...024456341
bacillus thuringiensis: a specific gamma-cyclodextrin producer strain.an anaerobic microbial isolate bacillus species, designated b. thuringiensis gu-2, was isolated from soil as a specific γ-cyclodextrin (cd) producer strain in alkaline medium under anaerobic conditions. the optimum ph and temperature for bacterial growth and γ-cd production were estimated to be ph 8.5 and 37°c in the presence of 1.0% starch substrate, respectively. a high purity yield >95% of γ-cd from the total cd yield in the reaction mixture was obtained from starch that was supposed to be co ...201424456970
optimization of bioinsecticides overproduction by bacillus thuringiensis subsp. kurstaki using linear regression.a multiple linear regression analyses were performed to screen for the significant factors simultaneously influencing production of deltaendotoxin, proteolytic activities and spore formation by a bacillus thuringiensis kurstaki strain. investigated factors included: ph of the medium, available oxygen and inoculum size. it was observed that oxygen availability was the most influencing setting on both deltaendotoxins production and spores counts, followed by initial ph of the medium and inoculum s ...201324459834
bacillus thuringiensis subsp. kurstaki hd1 as a factory to synthesize alkali-labile chia74∆sp chitinase inclusions, cry crystals and spores for applied use.the endochitinase chia74 is a soluble secreted enzyme produced by bacillus thuringiensis that synergizes the entomotoxigenecity of cry proteins that accumulate as intracellular crystalline inclusion during sporulation. the purpose of this study was to produce alkaline-soluble chia74∆sp inclusions in b. thuringiensis, and to determine its effect on cry crystal production, sporulation and toxicity to an important agronomical insect, manduca sexta. to this end we deleted the secretion signal peptid ...201424460864
microbial inoculants and organic amendment improves plant establishment and soil rehabilitation under semiarid conditions.the re-establishment of autochthonous shrub species is an essential strategy for recovering degraded soils under semiarid mediterranean conditions. a field assay was carried out to determine the combined effects of the inoculation with native rhizobacteria (bacillus megaterium, enterobacter sp, bacillus thuringiensis and bacillus sp) and the addition of composted sugar beet (sb) residue on physicochemical soil properties and lavandula dentata l. establishment. one year after planting, bacillus s ...201424463051
genetic resistance to bacillus thuringiensis alters feeding behaviour in the cabbage looper, trichoplusia ni.evolved resistance to xenobiotics and parasites is often associated with fitness costs when the selection pressure is absent. resistance to the widely used microbial insecticide bacillus thuringiensis (bt) has evolved in several insect species through the modification of insect midgut binding sites for bt toxins, and reports of costs associated with bt resistance are common. studies on the costs of bt-resistance restrict the insect to a single artificial diet or host-plant. however, it is well d ...201424465656
sequencing, de novo assembly and annotation of the colorado potato beetle, leptinotarsa decemlineata, transcriptome.the colorado potato beetle (leptinotarsa decemlineata) is a major pest and a serious threat to potato cultivation throughout the northern hemisphere. despite its high importance for invasion biology, phenology and pest management, little is known about l. decemlineata from a genomic perspective. we subjected european l. decemlineata adult and larval transcriptome samples to 454-flx massively-parallel dna sequencing to characterize a basal set of genes from this species. we created a combined ass ...201424465841
impacts of bt rice expressing cry1c or cry2a protein on the performance of nontarget leafhopper, nephotettix cincticeps (hemiptera: cicadellidae), under laboratory and field conditions.transgenic rice expressing bacillus thuringiensis berliner (bt) protein can effectively control target insects including stem borers and leaf folders. however, the potential effects of bt rice on nontarget organisms including nontarget herbivores have not been fully evaluated. in the current study, ecological fitness parameters of the nontarget herbivore, nephotettix cincticeps (uhler) (hemiptera: cicadellidae), fed on t1c-19 (cry1c) or t2a-1 (cry2a) rice were compared with non-bt rice (mh63) un ...201424472210
target and nontarget effects of novel "triple-stacked" bt-transgenic cotton 1: canopy arthropod communities.transgenic cotton varieties (bollgard ii) expressing two proteins (cry1ac and cry2ab) from bacillus thuringiensis (bt) have been widely adopted in australia to control larvae of helicoverpa. a triple-stacked bt-transgenic cotton producing cry1ac, cry2ab, and vip3a proteins (genuity bollgard iii) is being developed to reduce the chance that helicoverpa will develop resistance to the bt proteins. before its introduction, nontarget effects on the agro-ecosystem need to be evaluated under field cond ...201424472211
using resistant prey demonstrates that bt plants producing cry1ac, cry2ab, and cry1f have no negative effects on geocoris punctipes and orius insidiosus.geocoris punctipes (say) and orius insidiosus (say) are generalist predators found in a wide range of crops, including cotton (gossypium hirsutum l.) and maize (zea mays l.), where they provide important biological control services by feeding on an array of pests, including eggs and small larvae of caterpillars. a high percentage of cotton and maize in the united states and several other countries are transgenic cultivars that produce one or more of the insecticidal cry proteins of bacillus thur ...201424472212
established a new double antibodies sandwich enzyme-linked immunosorbent assay for detecting bacillus thuringiensis (bt) cry1ab toxin based single-chain variable fragments from a naïve mouse phage displayed library.scfvs are composed of the variable regions of the heavy and light chains via a short linker that maintain the specific antigen binding abilities of antibodies. in this study, we constructed a naïve mouse phage displayed library to generate scfvs against cry1ab toxin. after affinity panning, positive phage-scfvs were isolated, sequenced and characterized by elisa. the best binding ability scfv-g9 was expressed and purified. sds-page indicated that the relative molecular mass of scfv was estimated ...201424472345
effect of midgut proteolytic activity on susceptibility of lepidopteran larvae to bacillus thuringiensis subsp. kurstaki.bacillus thuringiensis (bt) is the most effective microbial control agent for controlling numerous species from different insect orders. all subspecies and strains of b. thuringiensis can produce a spore and a crystalline parasporal body. this crystal which contains proteinaceous protoxins is dissolved in the alkaline midgut, the resulting molecule is then cleaved and activated by proteolytic enzymes and acts as a toxin. an interesting aspect of this activation process is that variations in midg ...201324474937
aedes aegypti mos20 cells internalizes cry toxins by endocytosis, and actin has a role in the defense against cry11aa toxin.bacillus thuringiensis (bt) cry toxins are used to control aedes aegypti, an important vector of dengue fever and yellow fever. bt cry toxin forms pores in the gut cells, provoking larvae death by osmotic shock. little is known, however, about the endocytic and/or degradative cell processes that may counteract the toxin action at low doses. the purpose of this work is to describe the mechanisms of internalization and detoxification of cry toxins, at low doses, into mos20 cells from a. aegypti, f ...201424476709
dominant resistance to bt cotton and minor cross-resistance to bt toxin cry2ab in cotton bollworm from china.evolution of resistance by insect pests threatens the long-term benefits of transgenic crops that produce insecticidal proteins from bacillus thuringiensis (bt). previous work has detected increases in the frequency of resistance to bt toxin cry1ac in populations of cotton bollworm, helicoverpa armigera, from northern china where bt cotton producing cry1ac has been grown extensively for more than a decade. confirming that trend, we report evidence from 2011 showing that the percentage of individ ...201324478804
draft genome sequence of bacillus thuringiensis strain brmgv02-jm63, a chitinolytic bacterium isolated from oil-contaminated mangrove soil in brazil.here, we report the draft genome sequence and the automatic annotation of bacillus thuringiensis strain brmgv02-jm63. this genome comprises a set of genes involved in the metabolism of chitin and n-acetylglucosamine utilization, thus suggesting the possible role of this strain in the cycling of organic matter in mangrove soils.201424482524
coadministration of protoxin cry1ac from bacillus thuringiensis with metacestode extract confers protective immunity to murine cysticercosis.the bacillus thuringiensis cry1ac protoxin (pcry1ac) is a promising mucosal immunogen and adjuvant that induces protective immunity against naegleria fowleri and malaria infection models. we determined whether pcry1ac acted as a protective adjuvant against infection with taenia crassiceps. balb/c mice were thrice i.p. immunized with (i) pcry1ac, (ii) metacestode extract, (iii) extract + pcry1ac or (iv) vehicle, challenged with metacestodes on day 26 and then sacrificed 35 days later. cysticerci ...201424484070
nondestructive determination of transgenic bacillus thuringiensis rice seeds (oryza sativa l.) using multispectral imaging and chemometric methods.crop-to-crop transgene flow may affect the seed purity of non-transgenic rice varieties, resulting in unwanted biosafety consequences. the feasibility of a rapid and nondestructive determination of transgenic rice seeds from its non-transgenic counterparts was examined by using multispectral imaging system combined with chemometric data analysis. principal component analysis (pca), partial least squares discriminant analysis (plsda), least squares-support vector machines (ls-svm), and pca-back p ...201424491704
sinr controls enterotoxin expression in bacillus thuringiensis biofilms.the entomopathogen bacillus thuringiensis produces dense biofilms under various conditions. here, we report that the transition phase regulators spo0a, abrb and sinr control biofilm formation and swimming motility in b. thuringiensis, just as they control biofilm formation and swarming motility in the closely related saprophyte species b. subtilis. however, microarray analysis indicated that in b. thuringiensis, in contrast to b. subtilis, sinr does not control an eps operon involved in exopolys ...201424498128
market forces and technological substitutes cause fluctuations in the value of bat pest-control services for cotton.critics of the market-based, ecosystem services approach to biodiversity conservation worry that volatile market conditions and technological substitutes will diminish the value of ecosystem services and obviate the "economic benefits" arguments for conservation. to explore the effects of market forces and substitutes on service values, we assessed how the value of the pest-control services provided by mexican free-tailed bats (tadarida brasiliensis mexicana) to cotton production in the southwes ...201424498400
evaluation of tolerance to bacillus thuringiensis toxins among laboratory-reared western bean cutworm (lepidoptera: noctuidae).the western bean cutworm, striacosta albicosta (smith) (lepidoptera: noctuidae), is a destructive insect pest of dry beans and corn within its native range of western nebraska and eastern colorado. however, since the initiation of an eastward range expansion of s. albicosta in the late 1990s, economic damage has been observed in the midwest, and the species has now reached the atlantic coast and quebec. economic damage to corn occurs by larval feeding on ears, which is not controlled by commerci ...201324498749
indica rice cultivar irga 424, transformed with cry genes of b. thuringiensis, provided high resistance against spodoptera frugiperda (lepidoptera: noctuidae).plant expression of the entomopathogenic bacteria bacillus thuringiensis cry gene has reduced the damage created by insect pests in several economically important cultures. for this study, we have conducted genetic transformation of the indica rice "irga 424", via agrobacterium tumefaciens, using the b. thuringiensis cry1aa and cry1b genes, with the objective of obtaining rice plants resistant to the insect pests from this culture. the gene constructions harbor the promoters maize proteinase inh ...201324498761
the susceptibility of aedes aegypti populations displaying temephos resistance to bacillus thuringiensis israelensis: a basis for management.aedes aegypti is the vector of dengue virus, and its control is essential to prevent disease transmission. among the agents available to control this species, biolarvicides based on bacillus thuringiensis serovar israelensis (bti) are an effective alternative to replace the organophosphate temephos for controlling populations that display resistance to this insecticide. the major goal of this study was to determine the baseline susceptibility of brazilian ae. aegypti populations to bti, taking i ...201324499507
fitness costs and stability of cry1ab resistance in sugarcane borer, diatraea saccharalis (f.).the sugarcane borer, diatraea saccharalis (f.), is a major target species of transgenic corn expressing bacillus thuringiensis (bt) proteins in south america and the u.s. mid-south region. in this study, the fitness of seven insect genotypes of d. saccharalis were assayed on non-toxic diet, which included a cry1ab-susceptible strain (ss-2009), two cry1ab-resistant strains (rr-43a(bc), rr-l5b(bc)), and four f1 hybrids (f1-r43a(m)s(f), f1-r43a(f)s(m), f1-r5b(m)s(f), and f1-r5b(f)s(m)). the f1 hybr ...201424503242
inactivation and ultrastructure analysis of bacillus spp. and clostridium perfringens spores.bacterial endospores are resistant to many environmental factors from temperature extremes to ultraviolet irradiation and are generally more difficult to inactivate or kill than vegetative bacterial cells. it is often considered necessary to treat spores or samples containing spores with chemical fixative solutions for prolonged periods of time (e.g., 1-21 days) to achieve fixation/inactivation to enable electron microscopy (em) examination outside of containment laboratories. prolonged exposure ...201424503289
field efficacy of vectobac gr as a mosquito larvicide for the control of anopheline and culicine mosquitoes in natural habitats in benin, west africa.the efficacy of vectobac gr (potency 200 itu/mg), a new formulation of bacterial larvicide bacillus thuringiensis var. israelensis strain am65-52, was evaluated against anopheles gambiae and culex quinquefasciatus in simulated field and natural habitats in benin.201424505334
potency of insect-specific scorpion toxins on mosquito control using bacillus thuringiensis cry4aa.two insect-specific scorpion toxins, bjαit and aahit were produced as alkali-soluble protein inclusions in escherichia coli. the inclusion bodies themselves exhibited no toxicity against culex pipiens larvae. however, coadministration with cry4aa toxin enhanced the mosquitocidal activity by 2-3 fold. insect-specific scorpion toxins can be good supplements for cry toxin-based bioinsecticides.201424508022
a screening of five bacillus thuringiensis vip3a proteins for their activity against lepidopteran pests.five bacillus thuringiensis vip3a proteins (vip3aa, vip3ab, vip3ad, vip3ae and vip3af) and their corresponding trypsin-activated toxins were tested for their toxicity against eight lepidopteran pests: agrotis ipsilon, helicoverpa armigera, mamestra brassicae, spodoptera exigua, spodoptera frugiperda, spodoptera littoralis, ostrinia nubilalis and lobesia botrana. toxicity was first tested at a high dose at 7 and 10 days. no major differences were found when comparing protoxins vs. trypsin-activat ...201424508583
membrane binding and oligomer membrane insertion are necessary but insufficient for bacillus thuringiensis cyt1aa toxicity.bacillus thuringiensis cyt proteins are pore-forming toxins that have insecticidal activity mainly against dipteran insects. however, certain cyt proteins have toxicity to some insect orders, but not toxicity of cyt1aa against lepidopteran larvae has been found. insect specificity has been proposed to rely in specific binding to certain lipids on the brush border membrane of midgut cells since no protein receptors have been described so far. to determine the molecular basis of cyt1aa insect spec ...201324512949
application of statistical experimental design for optimisation of bioinsecticides production by sporeless bacillus thuringiensis strain on cheap medium.in order to overproduce bioinsecticides production by a sporeless bacillus thuringiensis strain, an optimal composition of a cheap medium was defined using a response surface methodology. in a first step, a plackett-burman design used to evaluate the effects of eight medium components on delta-endotoxin production showed that starch, soya bean and sodium chloride exhibited significant effects on bioinsecticides production. in a second step, these parameters were selected for further optimisation ...201324516462
immunotoxicological evaluation of corn genetically modified with bacillus thuringiensis cry1ah gene by a 30-day feeding study in balb/c mice.this study was to investigate the immunotoxicological potential of corn genetically modified (gm) with bacillus thuringiensis (bt) cry1ah gene in balb/c mice. female balb/c mice were randomly assigned to one of the four groups: the negative control group, the parental corn group, the gm corn group and the positive control group with 10 mice per group. mice in the gm corn group and the parental corn group were fed with diets containing 70% corresponding corn for 30 days. mice in the negative cont ...201424520311
a versatile system for functional analysis of genes and micrornas in cotton.cotton is an important economic crop worldwide. due to its long growth cycle, large genome size and recalcitrance to stable transformation, traditional methods for the analysis of gene function in this crop are difficult and labour intensive. here, we report a cotton leaf crumple virus (clcrv)-based vector and its application in gene function analysis through virus-induced gene silencing (vigs) and overexpression of micrornas (mirnas), small tandem target mimic (sttm) and artificial mirna (amirn ...201424521483
control of diatraea saccharalis by the endophytic pantoea agglomerans 33.1 expressing cry1ac7.despite the fact that bacillus thuringiensis (bt) is found in more than 90 % of the products used against insects, it has some difficulty reaching the internal regions where the larvae feed. to solve this problem, many genetically modified microorganisms that colonize the same pests have been developed. thus, the endophytic bacterium pantoea agglomerans (33.1), which has been recently described as a promising sugarcane growth promoter, was genetically modified with the pjtt vector (which carries ...201424531524
the ecological roles of bacillus thuringiensis within phyllosphere environments.bacillus thuringiensis (bt) is one of the most used bio-control agents to control plant insects, but little is known about its effect on the microbial population and communities on plant leaves. with the culture dependent method, it has been observed that the dynamics of bt within the phyllosphere varied dependent on both the doses of bt sprayed on the leaves and the plant species, however, bt's population size kept stable at about 1000 cfu g(-1) after 15 d since inoculation. by comparing the ba ...201424534157
bacterial tubulin tubz-bt transitions between a two-stranded intermediate and a four-stranded filament upon gtp hydrolysis.cytoskeletal filaments form diverse superstructures that are highly adapted for specific functions. the recently discovered tubz subfamily of tubulins is involved in type iii plasmid partitioning systems, facilitating faithful segregation of low copy-number plasmids during bacterial cell division. one such protein, tubz-bt, is found on the large pbtoxis plasmid in bacillus thuringiensis, and interacts via its extended c terminus with a dna adaptor protein tubr. here, we use cryo-electron microsc ...201424550513
assessment of a direct application of two bacillus thuringiensis israelensis formulations for immediate and residual control of aedes albopictus.the bacterial agent bacillus thuringiensis israelensis (bti) is a highly effective larvicide against various medically important mosquito and black fly vector species. recent formulations of this powerful larvicidal tool have been evaluated for their field efficacy in integrated mosquito management programs. laboratory and controlled-condition trials have indicated long periods of residual efficacy, whereas field persistence is often much lower in duration. we investigated the residual persisten ...201324551974
tradeoff between reproduction and resistance evolution to bt-toxin in helicoverpa armigera: regulated by vitellogenin gene expression.evolution of resistance to insecticides usually has fitness tradeoffs associated with adaptation to the stress. the basic regulation mechanism of tradeoff between reproduction and resistance evolution to bacillus thuringiensis (bt) toxin in the cotton bollworm, helicoverpa armigera (ha), based on the vitellogenin (vg) gene expression was analyzed here. the full-length cdna of the vg gene havg (jx504706) was cloned and identified. havg has 5704 base pairs (bp) with an open reading frame (orf) of ...201424555504
draft genome sequence of highly nematicidal bacillus thuringiensis db27.here, we report the genome sequence of nematicidal bacillus thuringiensis db27, which provides first insights into the genetic determinants of its pathogenicity to nematodes. the genome consists of a 5.7-mb chromosome and seven plasmids, three of which contain genes encoding nematicidal proteins.201424558243
function of two novel single-crd containing c-type lectins in innate immunity from eriocheir sinensis.c-type lectin is one of the pattern-recognition proteins of the non-self-innate immune system in invertebrates. in this study, two novel c-type lectin cdnas (esctl1 and esctl2) of eriocheir sinensis were cloned and characterized. esctl1 has 169 amino acids, whereas esctl2 has 164 amino acids. these two lectins contain one carbohydrate-recognition domain. phylogenetic analysis showed that esctl1 and esctl2 were not clustered with other reported lectins from crabs. esctl1 and esctl2 were expressed ...201424561128
cellular responses in bacillus thuringiensis cs33 during bacteriophage btcs33 infection.bacillus thuringiensis (bt) has been widely used for 50years as a biopesticide for controlling insect pests. however, bacteriophage infection can cause failures in 50%-80% of the batches during bt fermentation, resulting in severe losses. in the present work, the physiological and biochemical impacts of bt strain cs33 have been studied during bacteriophage infection. this study adopted a gel-based proteomics approach to probe the sequential changed proteins in phage-infected bt cells. to phage, ...201424565692
spiromastixones a-o, antibacterial chlorodepsidones from a deep-sea-derived spiromastix sp. fungus.fifteen new depsidone-based analogues named spiromastixones a-o (1-15) were isolated from the fermentation broth of a deep-sea spiromastix sp. fungus. their structures were elucidated on the basis of extensive nmr and mass spectroscopic analysis in association with chemical conversion. spiromastixones a-o are classified into two subtypes based on the orientation of ring c relative to ring a, while the n-propyl substituents on rings a and c are rarely seen in natural products. most analogues are ...201424571273
mode of action and specificity of bacillus thuringiensis toxins in the control of caterpillars and stink bugs in soybean culture.the bacterium bacillus thuringiensis (bt) produces delta-endotoxins that possess toxic properties and can be used as biopesticides, as well as a source of genes for the construction of transgenic plants resistant to insects. in brazil, the introduction of bt soybean with insecticidal properties to the velvetbean caterpillar, the main insect pest of soybean, has been seen a promising tool in the management of these agroecosystems. however, the increase in stink bug populations in this culture, in ...201424575310
diffusible signal factor (dsf) quorum sensing signal and structurally related molecules enhance the antimicrobial efficacy of antibiotics against some bacterial pathogens.extensive use of antibiotics has fostered the emergence of superbugs that are resistant to multidrugs, which becomes a great healthcare and public concern. previous studies showed that quorum sensing signal dsf (diffusible signal factor) not only modulates bacterial antibiotic resistance through intraspecies signaling, but also affects bacterial antibiotic tolerance through interspecies communication. these findings motivate us to exploit the possibility of using dsf and its structurally related ...201424575808
crustacean biodiversity as an important factor for mosquito larval control.newly established ponds, which are highly dynamic systems with changing levels of biological interactions among species, are common larval mosquito habitats. we investigated the impact of crustacean abundance and taxa diversity on mosquito oviposition and larval development. the effects of the biological larvicide bacillus thuringiensis israelensis (bti) on mosquito larvae were monitored according to fluctuations in crustacean communities. populations of the mosquito culex pipiens colonized arti ...201324581370
flavonoids from the halophyte apocynum venetum and their antifouling activities against marine biofilm-derived bacteria.eleven flavonoids were isolated from the leaves of the halophyte apocynum venetum. among them, the isolation of plumbocatechin a (1), 8-o-methylretusin (2) and kaempferol 3-o-(6″-o-acetyl)-β-d-galactopyranoside (7) was reported for the first time from this plant. their structures were identified by using spectral methods, including 2d nmr experiments, and confirmed by comparing with the literature data. in addition, the antifouling activities of these compounds against the marine fouling bacteri ...201424588258
evaluation of different culture media for improvement in bioinsecticides production by indigenous bacillus thuringiensis and their application against larvae of aedes aegypti.production of indigenous isolate bacillus thuringiensis sv2 (bt sv2) was checked on conventional and nonconventional carbon and nitrogen sources in shake flasks. the effects on the production of biomass, toxin production, and spore formation capability of mosquito toxic strain were determined. toxicity differs within the same strain depending on the growth medium. bt sv2 produced with pigeon pea and soya bean flour were found highly effective with lc50 < 4 ppm against larvae of aedes aegypti. th ...201424592157
design and synthesis of 2-styryl of 5-nitroimidazole derivatives and antimicrobial activities as fabh inhibitors.a series of 2-styryl-5-nitroimidazole derivatives (25-48) have been synthesized and their biological activities were also evaluated against two gram-negative bacterial strains: escherichia coli and pseudomonas aeruginosa and two gram-positive bacterial strains: bacillus subtilis and bacillus thuringiensis as potential fabh inhibitors. all the compounds were structurally determined by (1)h nmr, ms, and elemental analysis. e. coli β-ketoacyl-acyl carrier protein synthase iii inhibitory assay and d ...201424594526
field deposition of bt transgenic corn pollen: lethal effects on the monarch butterfly.we present the first evidence that transgenic bacillus thuringiensis (bt) corn pollen naturally deposited on asclepias syriaca; common milkweed, in a corn field causes significant mortality of danaus plexippus l. (lepidoptera: danaidae) larvae. larvae feeding for 48 h on a. syriaca plants naturally dusted with pollen from bt corn plants suffered significantly higher rates of mortality at 48 h (20±3%) compared to larvae feeding on leaves with no pollen (3±3%), or feeding on leaves with non-bt pol ...200024595835
transgenic tomato line expressing modified bacillus thuringiensis cry1ab gene showing complete resistance to two lepidopteran pests.the modified truncated bt-cry1ab gene of bacillus thuringiensis has been used for the development and selection of over expressing transgenic events in a commercially important variety of tomato (solanum lycopersicum l.) by agrobacterium-mediated leaf-disc transformation procedure. the integration and inheritance of cry1ab gene in t0 transgenic plants and their progenies were determined by pcr, rt-pcr and southern blot hybridization analysis. the toxin expression was monitored by double antibody ...201424600542
pyrethroid resistance in aedes aegypti larvae (diptera: culicidae) from singapore.we report the first comprehensive insecticide susceptibility status ofaedes aegypti (l.) larvae from singapore. the study indicated that ae. aegypti is susceptible to temephos, although resistance (rr50 = 1.29-4.43-fold) couldbe developing. of high concern is the detection of moderate to high resistance to permethrin (rr50 = 29-47-fold) and etofenprox (rr50 = 14-34-fold). biolarvicide bacillus thuringiensis israelensis (bti) remains effective. the insecticide susceptibility profile of ae. aegypt ...201424605467
evaluation of a disinfectant wipe intervention on fomite-to-finger microbial transfer.inanimate surfaces, or fomites, can serve as routes of transmission of enteric and respiratory pathogens. no previous studies have evaluated the impact of surface disinfection on the level of pathogen transfer from fomites to fingers. thus, the present study investigated the change in microbial transfer from contaminated fomites to fingers following disinfecting wipe use. escherichia coli (10(8) to 10(9) cfu/ml), staphylococcus aureus (10(9) cfu/ml), bacillus thuringiensis spores (10(7) to 10(8) ...201424610856
cry8ca2-containing layer-by-layer microcapsules for the ph-controlled release of crystal protein.to extend the activity of crystal proteins by protection from environmental stress, we developed a new type of microcapsule containing cry8ca2 protoxins. layer-by-layer (lbl) microcapsules containing cry8ca2 were successfully prepared for the first time by the alternate deposition of poly(acrylic acid) (pah) and cry8ca2 at ph 6 on the surface of poly(styrene sulphonate) (pss)-doped caco3 microbeads. scanning electron microscopy (sem) photos showed that microparticles were spherical in shape, app ...201424617704
bt rice producing cry1c protein does not have direct detrimental effects on the green lacewing chrysoperla sinica (tjeder).the effects of insect-resistant genetically engineered rice producing cry1c protein derived from bacillus thuringiensis (bt) on chrysoperla sinica (tjeder) (neuroptera: chrysopidae) were assessed in laboratory bioassays. survival and development of c. sinica larvae were not adversely affected when the larvae were fed a diet containing purified cry1c protein at 200 µg/g fresh weight, representing a worst-case exposure scenario; in contrast, c. sinica larvae were adversely affected when the diet c ...201424619941
draft genome sequence of bacillus thuringiensis serovar tolworthi strain na205-3, an isolate toxic for helicoverpa armigera.we report here the complete annotated 6,510,053-bp draft genome sequence of bacillus thuringiensis serovar tolworthi strain na205-3, which is toxic for helicoverpa armigera. this strain potentially contains nine insecticidal toxin genes homologous to cry1aa12, cry1ab1, cry1ab8, cry1ba1, cry1af1, cry1ia10, vip1bb1, vip2ba2, and vip3aa6.201424625875
bacillus thuringiensis db27 produces two novel protoxins, cry21fa1 and cry21ha1, which act synergistically against nematodes.bacillus thuringiensis has been widely used as a biopesticide, primarily for the control of insect pests, but some b. thuringiensis strains specifically target nematodes. however, nematicidal virulence factors of b. thuringiensis are poorly investigated. here, we describe virulence factors of nematicidal b. thuringiensis db27 using caenorhabditis elegans as a model. we show that b. thuringiensis db27 kills a number of free-living and animal-parasitic nematodes via intestinal damage. its virulenc ...201424632254
bacillus thuringiensis cry4aa insecticidal protein: functional importance of the intrinsic stability of the unique α4-α5 loop comprising the pro-rich sequence.the long loop connecting transmembrane α4 and α5 of the bacillus thuringiensis cry4aa toxin possesses a unique feature with pro-rich sequence (pro(193)pro(194)_pro(196)) which was shown to be crucial for toxicity. here, the structural role in the intrinsic stability of the pro-rich sequence toward toxin activity was investigated. three val-substituted mutants (p193v, p194v and p196v) and one phe-substituted mutant (p193f) were generated and over-expressed in escherichia coli as inclusions at lev ...201424632526
common virulence factors and tissue targets of entomopathogenic bacteria for biological control of lepidopteran pests.this review focuses on common insecticidal virulence factors from entomopathogenic bacteria with special emphasis on two insect pathogenic bacteria photorhabdus (proteobacteria: enterobacteriaceae) and bacillus (firmicutes: bacillaceae). insect pathogenic bacteria of diverse taxonomic groups and phylogenetic origin have been shown to have striking similarities in the virulence factors they produce. it has been suggested that the detection of phage elements surrounding toxin genes, horizontal and ...201424634779
analysis of the interaction between bacillus coagulans and bacillus thuringiensis s-layers and calcium ions by xrd, light microscopy, and ftir.s-layer is a self-assemble regularly crystalline surface that covers major cell wall component of many bacteria and archaea and exhibits a high metal-binding capacity. we have studied the effect of the calcium ions and type of solid support (glass or mica) on the structure of the s-layers from bacillus coagulans hn-68 and bacillus thuringiensis mh14 upon simple methods based on light microscopy and afm. furthermore, the fourier transform infrared spectroscopy (ftir) study is indicated that the c ...201424639088
field-evolved resistance by western corn rootworm to multiple bacillus thuringiensis toxins in transgenic maize.the widespread planting of crops genetically engineered to produce insecticidal toxins derived from the bacterium bacillus thuringiensis (bt) places intense selective pressure on pest populations to evolve resistance. western corn rootworm is a key pest of maize, and in continuous maize fields it is often managed through planting of bt maize. during 2009 and 2010, fields were identified in iowa in which western corn rootworm imposed severe injury to maize producing bt toxin cry3bb1. subsequent b ...201424639498
[biological agents for controlling the density of blood-sucking black flies (diptera: simuliidae) in the north of armenia].biological agents were found to have high larvicidal activity against simuliidae of two bacillus thuringiensis spp. israelensis strains. to reduce the number of the pre-imago stages of black flies, the biological agent blp-2477 should be used as most effective from an environmental point of view.201424640132
tri-trophic studies using cry1ac-resistant plutella xylostella demonstrate no adverse effects of cry1ac on the entomopathogenic nematode, heterorhabditis bacteriophora.the potential impacts on natural enemies of crops that produce insecticidal cry proteins from bacillus thuringiensis (bt) are an important part of an environmental risk assessment. entomopathogenic nematodes are important natural enemies of lepidopteran pests, and the effects of bt crops on these nontarget organisms should be investigated to avoid disruption of their biological control function. the objective of this study was to investigate the effects of cry1ac-expressing transgenic bt broccol ...201424665692
use of spent mushroom substrate for production of bacillus thuringiensis by solid-state fermentation.the aim of this study was to explore a cost-effective method for the mass production of bacillus thuringiensis (bt) by solid-state fermentation. as a locally available agroindustrial byproduct, spent mushroom substrate (sms) was used as raw material for bt cultivation, and four combinations of sms-based media were designed. fermentation conditions were optimized on the best medium and the optimal conditions were determined as follows: temperature 32 degrees c, initial ph value 6, moisture conten ...201424665695
bioactivity of piper hispidinervum (piperales: piperaceae) and syzygium aromaticum (myrtales: myrtaceae) oils, with or without formulated bta on the biology and immunology of spodoptera frugiperda (lepidoptera: noctuidae).the combination of essential oils and bacillus thuringiensis berliner may represent an interesting control strategy. thus, the study tested the following hypothesis: the combination of long pepper oil (piper hispidinervum l.) and clove (syzygium aromaticum l.) oils in two concentrations with xentari wg (bta) yields a more effective control of spodoptera frugiperda (je smith) (lepidoptera: noctuidae) affecting biological and reproductive parameters and leading to changes in the levels of phenolox ...201424665696
fitness costs associated with field-evolved resistance to bt maize in spodoptera frugiperda (lepidoptera: noctuidae).increasing adoption of transgenic crops expressing cry toxin genes from bacillus thuringiensis (bt crops) represents an augmented risk for development of insect resistance. while fitness costs can greatly influence the rate of resistance evolution, most available data related to bt resistance have been obtained from laboratory-selected insect strains. in this article, we test the existence of fitness costs associated with high levels of field-evolved resistance to bt maize event tc1507 in a stra ...201424665719
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