the multicomponent genome of a different cytoplasmic polyhedrosis virus isolated from heliothis armigera.the genome of a new cytoplasmic polyhedrosis virus (cpv) isolated from heliothis armigera has been shown to consist of 10 double-stranded rna segments, as in other cpvs, but the genome profile on page bears no resemblance to previously described cpvs isolated from h.armigera.1978361635
isolation of a cytoplasmic polyhedrosis virus by physical and immunological techniques.procedures are described for the separation and purification of cytoplasmic polyhedrosis viruses obtained from multiply infected heliothis armigera larvae. separation was achieved by differential centrifugation and density gradient zone electrophoresis followed by complexing with nuclear polyhedrosis virus specific antibody. the yield of cytoplasmic polyhedrosis virus was increased by passage in larvae reared on synthetic media.19751098037
the insecticidal crystal protein cryia(c) from bacillus thuringiensis is highly toxic for heliothis armigera. 19921541846
location and nucleotide sequence of the gene encoding the viral enhancing factor of the trichoplusia ni granulosis virus.the gene encoding the viral enhancing factor (vef) of trichoplusia ni granulosis virus has been cloned from a lambda gt11 expression library, and the complete nucleotide sequence determined. the vef gene encodes a protein with a predicted mr of 104k which does not share homology with any previously reported proteins. a possible promoter is located four nucleotides upstream of the initiation codon and represents a consensus baculovirus late promoter (ataag). this has been confirmed by the identif ...19911940861
photoprotection of bacillus thuringiensis kurstaki from ultraviolet irradiation.irradiation of bacillus thuringiensis var. kurstaki hd1 at 300-350 nm for up to 12 hr using a photochemical reactor results in a rapid loss of its toxicity to larvae of heliothis armigera. photoprotection of the toxic component was obtained by adsorption of cationic chromophores such as acriflavin (af), methyl green, and rhodamine b to b. thuringiensis. af gave the best photoprotection and a level of 0.42 mmol/g dye absorbed per gram of b. thuringiensis was highly toxic even after 12 hr of ultra ...19912066575
role of insects as inhalant allergens in bronchial asthma with special reference to the clinical characteristics of patients.the whole body extracts (wbes) of 13 common insects from delhi, namely musca domestica (house fly); sitophilus oryzae (rice weevil); callosobrochous maculatus (pulse beetle); anopheles stephensi, culex quinquefasciatus and aedes aegypti (mosquitoes); blattella germanica and periplaneta americana (cockroaches: male, female and nymph); spodoptera litura and heliothis armigera (moths), were prepared to evaluate their allergenic significance in patients with allergic bronchial asthma. intradermal (i ...19902253082
bacillus thuringiensis potency bioassays against heliothis armigera, earias insulana, and spodoptera littoralis larvae based on standardized diets.bacillus thuringiensis screening programs based on the official potency bioassay using third-instar larvae and on a neonate bioassay were developed for heliothis armigera, earias insulana, and spondoptera littoralis. in these bioassays, the diets were standardized to be suitable, with minor modifications, for feeding of the three lepidopterans. the bioassay protocol was based on determination of the lc50 of the microbial standard hd-1-s-80 in the insects susceptible to b. thuringiensis var. kurs ...19902351843
cytoplasmic polyhedrosis virus classification by electropherotype; validation by serological analyses and agarose gel electrophoresis.serological analyses of several different cytoplasmic polyhedrosis viruses (cpvs), including two type 1 cpvs from bombyx mori, type 1 cpv from dendrolimus spectabilis, type 12 cpv from autographa gamma, type 2 cpv from inachis io, type 5 cpv from orgyia pseudotsugata and type 5 cpv from heliothis armigera, demonstrated a close correlation between the antigenic properties of the polyhedrin or virus particle structural proteins and the genomic dsrna electropherotypes. the dsrnas of these viruses w ...19892499658
dna homology relationships between spodoptera littoralis nuclear polyhedrosis virus and other baculoviruses.the dna sequence homology relationships between spodoptera littoralis nuclear polyhedrosis virus (npv) and five other lepidopteran npvs were studied by hybridization of 32p-labeled npv dnas to southern blots of restriction-endonuclease-digested npv dna. the s. littoralis npv (slmnpv) shows extensive dna sequence homology through most of the genome with s. frugiperda npv and s. exigua npv. heliothis armigera npv, h. zea npv, and autographa californica npv (acmnpv) share fewer regions of homology ...19852995274
[properties of the nuclear polyhedrosis virus].four passages of barathra brassicae l nuclear polyhedrosis virus (npv) in heliothis armigera hbn caterpillars were carried out. b. brassicae npv was found to be highly infective for caterpillars of both species. when h. armigera caterpillars were infected with b. brassicae npv, reproduction of the latter occurred alongside with the induction of h. armigera latent virus. in subsequent passages the latent virus replaced the foreign npv. it was noted in mixed infection that in the 2nd passage the a ...19853913136
bioassay of a nuclear-polyhedrosis virus and bacillus thuringiensis against the american bollworm, heliothis armigera, in botswana. 19744597764
weight-related susceptibility of larvae of heliothis armigera to a crude nuclear-polyhedrosis virus preparation. 19744597767
midgut and viral associated proteases of heliothis armigera.the role played by the gut juice of insects in the infective process of insect viruses was examined. analysis of larval gut extract of heliothis armigera by sds-page revealed protease activity associated with components of molecular weights 48,000 and 94,000. proteases were found to be associated with occlusion bodies and virions of both nuclear polyhedrosis virus (npv) and cytoplasmic polyhedrosis virus (cpv) infecting h. armigera. cpv occlusion bodies were dissolved by gut juice extract at ph ...19836337972
utilization of fodder yeast and agro-industrial by-products in production of spores and biologically - active endotoxins from bacillus thuringiensis.a number of newly-devised fermentation media were evaluated with respect to their ability to support sporulation and biosynthesis of endotoxins by strains of bacillus thuringiensis that are biologically active against spodoptera littoralis, heliothis armigera, and spodoptera exigua. fodder yeast from dried cells of saccharomyces cerevisiae could be used as a complete mono-component medium for production of highly active spore-delta-endotoxin complexes from b. thur., vars. entomocidus, kurstaki a ...19836666415
some physical characteristics of a cytoplasmic polyhedrosis virus of heliothis armigera.a number of physical properties of a cytoplasmic polyhedrosis virus of heliothis armigera were determined. these included a buoyant density of 1.44 g/cm3, a diffusion coefficient of 0.73 x 10(-7) cm2/sec, a partial specific volume of 0.688 ml/g, and a sedimentation coefficient of 399s. three different methods were used to determine an average molecular weight of 47.4 x 10(6).19806987192
virus envelope acquisition of nuclear polyhedrosis virus in vitro.there have been several reports concerned with the replication and morphogenesis of insect baculoviruses during the past decade [1--7]. while there is general agreement as to the assembly of the virus on the basis of electron microscopic studies, there are still questions regarding the details of the replicative mechanisms, such as the acquisition of the virus envelope. three possible ways have been proposed to describe envelope formation of nuclear polyhedrosis virus: (i) acquisition of budding ...19817018096
[characters and insecticidal polypeptide of a new strain of bacillus thuringiensis subsp. kenyae in china].a new strain of bacillus thurinigiensis bt with high toxicity against noctuidae larvae has been screened for many generations since isolated from larvae candle of aphomia gularis in yiyang county, jiangxi province, in china. by comparison and analysis of results of physiological and biochemical test, flagella antigen identification and esterase type, the strain is identified as h4a-4c bt serovar. kenyae. since its crystal protein type and plasmid type are different from those of bt serovar. keny ...19957483588
functional expression of an alpha anti-insect scorpion neurotoxin in insect cells and lepidopterous larvae.the leiurus quinquestriatus hebraeus alpha anti-insect toxin (lqh alpha it) cdna was engineered into the autographa californica nuclear polyhedrosis virus (acnpv) genome. insect cells infected with the recombinant virus secreted a functional lqh alpha it polypeptide. spodoptera littoralis and heliothis armigera larvae injected with recombinant budded virus, showed typical intoxication symptoms. this recombinant virus showed enhanced insecticidal potency against h. armigera larvae compared with w ...19957498537
highly insect-resistant transgenic tobacco plants containing both b.t. and cpti genes.the cowpea trypsin inhibitor (cpti) gene was synthesized according to its cdna sequence using dna synthesizer and confirmed by dna sequencing. the cpti gene and modified bacillus thuringiensis (b.t.) delta-endotoxin gene were cotransformed to tobacco explants mediated by agrobacterium tumefaciens. the integrations of b.t and cpti genes were confirmed by pcr and southern hybridization. three kinds of transgenic plants were obtained: (1) containing cpti gene, (2) containing b.t gene, (3) containin ...19957548766
toxicity, penetration, tissue distribution, and metabolism of methyl parathion in helicoverpa armigera and h. punctigera (lepidoptera: noctuidae).toxicity of c14-ring-methyl parathion in penetration, tissue absorption, and metabolism by susceptible helicoverpa armigera (hübner) and helicoverpa punctigera (wallengren) larvae was compared. c14 methyl parathion penetrated the cuticle of h. punctigera more rapidly than of h. armigera, leading to initially higher internal insecticide concentrations in h. punctigera. the same methyl-parathion metabolites were recovered from h. armigera and h. punctigera. however, larger quantities of methyl par ...19947962948
analysis of the c-polyhedrin genes from different geographical isolates of a type 5 cytoplasmic polyhedrosis virus.the c-polyhedrin genes of two different geographic isolates of a type 5 cytoplasmic polyhedrosis virus (cpv) were cloned. a cpv infecting orgyia pseudotsugata (opcpv), isolated in the pacific northwest of the u.s.a., and a cpv infecting heliothis armigera, isolated in south africa, were studied. both genes were found to be 883 nucleotides in length and encoded a predicted protein of 246 residues (m(r) of 28,890). comparison of the nucleotide sequences of these two viruses with another type 5 geo ...19948046399
expression of beta-galactosidase and luciferase in insect cell lines infected with a recombinant acmnpv recombinant (ac-gal-luc) carrying the beta-galactosidase and luciferase genes under the control of the p10 and polyhedrin promoters, respectively, was used to study expression in nine insect cell lines. all acmnpv-permissive cell lines expressed both reporter genes with the coleopteran cell line, anthonomus grandis (age), producing the highest concentrations of beta-galactosidase (5.0 x 10(6) pg/ml) and luciferase (2.67 x 10(3) pg/ml). both enzymes were detected as early as 12 h postin ...19948069450
a gene encoding a highly expressed spindle body protein of heliothis armigera entomopoxvirus.the gene encoding the most abundant protein of purified preparations of heliothis armigera entomopoxvirus (haepv) has been cloned and sequenced. the gene sequence encodes a 40.1k polypeptide with a putative n-terminal 20 amino acid leader peptide, and a single potential n-glycosylation site. analysis of the protein, which has an apparent m(r) of 50k on polyacrylamide gels, confirmed post-translational loss of the leader peptide, but showed no evidence of glycosylation. the protein is related to ...19938376960
an entomopoxvirus homologue of the vaccinia virus d13l-encoded 'rifampicin resistance' protein.the heliothis armigera entomopoxvirus (haepv) genome encodes a predicted 68 kda polypeptide related to the 'rifampicin resistance' protein of vaccinia virus (with 30 % identity), and an homologous swinepox virus protein (27% identity). we were unable to isolate an haepv genotypic variant encoding a predicted c-terminal truncated form of the protein, suggesting that the c terminus of the molecule may be essential to protein function, and, in turn, that this function may be essential to viral repl ...19968609479
[construction of shuttle vector containing delta-endotoxin gene of bacillus thuringiensis].the bacillus thuringiensis toxin gene cryia(c) was inserted into the shuttle vector pbe-2 to construct pamy for expressing the b.t. gene in both gram-negative and -positive bacterial systems. pamy was introduced into wild type bacillus cereus, b.brevis and b.subtilis by electroporation. transformants containing delta-endotoxin gene produced proteins reacted with b.t. crystal protein antibody. upon biological toxicity tests, the transformants gave a mortality of 100% against ostrinia furnacilis, ...19968762474
cloning and sequencing of the gene for an enhancing factor from pseudaletia separata enhancing factor (ef) has been shown to increase the susceptibility of the armyworm, pseudaletia separata, to this nuclear polyhedrosis virus. using amino acid microsequencing data obtained from the purified ef protein, we cloned and sequenced the gene for ef. the deduced amino acid sequence exhibited a significant similarity to major spindle proteins, fusolins, whose function is unknown, from heliothis armigera, choristoneura biennis and melolontha melolontha entomopoxviruses.19968921880
are odorant-binding proteins involved in odorant discrimination?pheromone-sensitive sensilla trichodea of nine moth species belonging to six families and three superfamilies of lepidoptera were immunolabelled with an antiserum against the pheromone-binding protein of antheraea polyphemus. strong immunolabelling of the sensillum lymph was observed in all long sensilla trichodea of a. polyphemus, a. pernyi (saturniidae), bombyx mori (bombycidae) and manduca sexta (sphingidae). very weak labelling was found with all sensilla trichodea of dendrolimus kikuchii (l ...19968985600
sequence of rna2 of the helicoverpa armigera stunt virus (tetraviridae) and bacterial expression of its genes.the complete nucleotide sequence of rna2 of helicoverpa armigera stunt virus (hasv), a member of the tetraviridae, was determined by characterization of cloned cdna and pcr products and direct sequencing of genomic rna. the capped, positive sense, single-stranded rna is 2478 nucleotides in length and has two overlapping open reading frames (orfs) likely to be cistrons which are situated between terminal non-coding regions of 282 and 168 bases, 5' and 3', respectively. extensive secondary structu ...19959049325
laboratory screening of different bacillus thuringiensis strains against certain lepidopteran pests and subsequent field evaluation on the pod boring pest complex of pigeonpea (cajanus cajan).laboratory evaluation of different bacillus thuringiensis subspecies revealed that b. thuringiensis subsp. kurstaki (ncim 2514) at 10(8) spores/ml concentration caused more than 85% mortality to the neonate larvae of the lepidopteran insects spodoptera litura (f.) and phthorimaea operculella (z.). this strain at 10(10) spores/ml concentration was effective against the major lepidopteran pests comprising the pod boring complex of pigeonpea (cajanus cajan), viz. helicoverpa armigera (h.) and exela ...19979195006
cytochrome p450 genes from helicoverpa armigera: expression in a pyrethroid-susceptible and -resistant strain.the molecular basis of metabolic resistance to pyrethroids in helicoverpa armigera is currently under debate. substantial indirect evidence supports a role for both esterase- and cytochrome-p450-mediated metabolism. however, the relative roles played by these two mechanisms in field-based resistance is uncertain. our understanding of the importance of p450-mediated metabolism is hindered by the paucity of cloned genes from this species, and the corresponding absence of data on rates of insectici ...19979304792
cytochrome p450 (cyp)9a1 in heliothis virescens: the first member of a new cyp family.a novel cytochrome p450 cdna with its complete coding sequence and part or all of the 3' (77 nucleotides) and 5' (87 nucleotides) non-coding sequence was isolated from the tobacco budworm, heliothis virescens (f). the 1763 nucleotide sequence encodes a protein of 532 amino acids which includes a hydrophobic n-terminal region and the highly conserved heme binding regions typical of p450s. low sequence similarity to other p450 sequences and the presence of a thromboxane synthase-like insertion ups ...19979304798
molecular analysis of an enhancin gene in the lymantria dispar nuclear polyhedrosis virus.a lymantria dispar nuclear polyhedrosis virus (ldmnpv) gene has been identified that encodes a homolog to the granulovirus (gv) enhancin proteins that are capable of enhancing the infection of other baculoviruses. enhancin genes have been identified and sequenced for three species of gvs but have not been found in any other nuclear polyhedrosis virus to date. the ldmnpv enhancin gene is located between 67.6 and 70.1 kbp on the viral genome. northern and primer extension analyses of viral rnas in ...19979343163
lepidopteran peptides of the allatostatin superfamily.peptides of the allatostatin superfamily with the c-terminal amino acid sequence -yxfgl-nh2 have been isolated and identified from the lepidopterans, the codling moth, cydia pomonella (tortricidae) and the bollworm, helicoverpa armigera (noctuidae). the peptides, designated cydiastatins and helicostatins respectively, were monitored during purification with radioimmunoassays based on the callatostatins of the blowfly calliphora vomitoria. the eight peptides from each of the two species appear to ...19979392829
amylase inhibitors of pigeonpea (cajanus cajan) seeds.pigeonpea (cajanus cajan l) seeds were analysed quantitatively for amylase inhibitor (ai) activity and qualitatively, by an in-gel-detection method on polyacrylamide gels. at least four ai isoforms were identified in pigeonpea seeds. the ais inhibit human salivary and bovine pancreatic amylase but fail to inhibit bacterial, fungal and endogenous amylase. pigeonpea ais were found to be active over a ph range of 4.5 to 9.5 and were heat labile. the isoelectric point of a major inhibitor is 6.2 ais ...19989431672
learning in host selection in helicoverpa armigera (hubner) (lepidoptera: noctuidae)the effect of experience on pre- and post-alighting host selection in adult female helicoverpa armigera was tested in an indoor flight cage, and in a large greenhouse. the moths had experienced either tobacco or tomato plants (both are hosts of h. armigera) for 3 days, or were given no experience. individuals were then released and their host selection assessed. all individuals caught in the greenhouse were identified and tested for post-alighting acceptance on each host. experience significantl ...19989480690
analysis of the ecdysteroid udp-glucosyltransferase gene of heliothis armigera single-nucleocapsid ecdysteroid udp-glucosyltransferase (egt) gene was identified from the single (s) nucleocapsid nucleopolyhedrovirus of heliothis armigera (hearnpv). in baculovirus-infected insects the viral enzyme (egt) plays a pivotal role in abrogating the insect molting process. the open reading frame of the egt gene is 1545 nucleotides long, encoding a putative protein of 515 amino acids with a mr of 59.1. the 5'-noncoding region contains a putative early (cagt) and late (taag) motif for transcription in ...19979482587
novel mutations in the para-homologous sodium channel gene associated with phenotypic expression of nerve insensitivity resistance to pyrethroids in heliothine lepidoptera.coding sequences from the intracellular segment linking repeat domains iii and iv of the para-homologous sodium channel gene were amplified and cloned from two species of heliothine larvae using rt-pcr techniques. sequence comparisons between standard laboratory susceptible and nerve insensitive strains of the tobacco budworm (heliothis virescens) and the cotton bollworm (helicoverpa armigera) identified two mutations. these were an aspartic acid (gac) to valine (gtc) and a glutamic acid (gaa) t ...19989535164
in vitro and in vivo host range of anticarsia gemmatalis multiple nuclear polyhedrosis virus.a clone of the wild type (wt) anticarsia gemmatalis multiple nuclear polyhedrosis virus agmnpv, derived from a geographical isolate (hondrina, brazil) and designated agmnpv-cl4-3a1, was used to determine the host range of this virus in six established lepidopteran cell lines: anticarsia gemmatalis (bcirl-ag-am1), helicoverpa zea (bcirl-hz-am1), heliothis virescens (bcirl-hv-am1), helicoverpa armigera (bcirl-ha-am1), trichoplusia ni (tn-cl1), bombyx mori (bmn), and a coleopteran cell line anthono ...19989542640
[distribution of bacillus thuringiensis in soils of north and south of china].221 isolates of bacillus thuringiensis were isolated in 1491 soil samples from north and south of china. h-serotypes and larvicidal characters of all bt isolates have been identified. the rate of bt-harbouring soil sample and the rate of bt isolates in northeast and neimeng were in 12.6% and 17.2% respectively. predominant serotypes were h4, h10, h3, h13, h5 and h29. the most fertile bt-harbouring area was the heilongjiang province with rate of bt-harbouring sample of 21.4% and rate of bt isolat ...19969639831
processing of delta-endotoxin of bacillus thuringiensis subsp. kurstaki hd-1 in heliothis armigera midgut juice and the effects of protease inhibitors.bombyx mori was found to be more sensitive to the protoxins of hd-1 than heliothis armigera. sds-page analysis showed that a large amount of activated toxin was yielded from protoxin by b. mori gut juice while little was yielded by h. armigera. further degradation of activated toxin was observed in h. armigera midgut juice detected by sds-page. ph influenced the proteolytic activity of the midgut juice significantly, but there was no obvious effect of ph on the degradation of activated toxin. sp ...19989647704
a gloverin-like antibacterial protein is synthesized in helicoverpa armigera following bacterial challenge.a bacteria inducible antibacterial protein, p2, was isolated from the old world bollworm helicoverpa armigera. fifth-instar larvae were injected with live escherichia coli nctc 8196. p2 was isolated by hplc using reversed-phase and size-exclusion columns. in addition, p2 was isolated by an alternative method of sequential cation-exchange and reversed-phase hplc. the structure of p2 was determined by n-terminal edman degradation and mass spectrometry. p2 had similar mass (14.1 kda) structure and ...19989699484
environmental distribution and diversity of bacillus thuringiensis in spain.bacillus thuringiensis was isolated from 301 out of 1,005 samples collected in spain from agricultural and non-cultivated soils, dust from stored products, and dead insects. based on the production of parasporal crystals, 1,401 isolates were identified as b. thuringiensis after examining 11,982 b. thuringiensis-like colonies. we found a greater presence of b. thuringiensis in dust from grain storages than in other habitats. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the spore-c ...19989741114
efficacy of lepidopteran specific delta-endotoxins of bacillus thuringiensis against helicoverpa armigera 19989784360
serial passage of a helicoverpa armigera nucleopolyhedrovirus in helicoverpa zea cell cultures.the serial passaging of baculoviruses in cell lines numerous times can result in a variety of mutations or defective viral populations becoming predominant in the cultures. the generation of these mutants during cell culture passage, also known as "the passage effect," can seriously hinder the use of in vitro methods for large-scale production of baculoviruses for use as biopesticides. in an effort to develop a large-scale in vitro method of producing helicoverpa armigera singly enveloped nucleo ...199910222185
sequence of the genomic rna of nudaurelia beta virus (tetraviridae) defines a novel virus genome organization.the monopartite genome of nudaurelia beta virus, the type species of the betatetravirus genus of the family tetraviridae, consists of a single-stranded positive-sense rna (ss+rna) of 6625 nucleotides containing two open reading frames (orfs). the 5' proximal orf of 5778 nucleotides encodes a protein of 215 kda containing three functional domains characteristic of rna-dependent rna polymerases of ss+rna viruses. the 3' proximal orf of 1836 nucleotides, which encodes the 66-kda capsid precursor pr ...199910329566
the establishment of heliothine cell lines and their susceptibility to two baculoviruses.a total of eight cell lines were established from helicoverpa armigera (3) and h. punctigera (5) embryos and ovaries. cell lines were established and grown in tc100 and/or tc199-mk containing 10% fetal bovine serum. the serum-free medlium excell 400 was also used, with and without 10% supplemental fetal bovine serum, but failed to generate cell lines from fat bodies, embryos, or ovarian tissues. cell lines consisted of heterogenous cell types ranging from oval to fibroblast-like. this is the fir ...199910475263
amino acid substitution in alpha-helix 7 of cry1ac delta-endotoxin of bacillus thuringiensis leads to enhanced toxicity to helicoverpa armigera hubner.insecticidal proteins or delta-endotoxins of bacillus thuringiensis are highly toxic to a wide range of agronomically important pests. the toxins are formed of three structural domains. the n-terminal domain is a bundle of eight alpha-helices and is implicated in pore formation in insect midgut epithelial membranes. all the delta-endotoxins share a common hydrophobic motif of eight amino acids in alpha-helix 7. a similar motif is also present in fragment b of diphtheria toxin (dt). site-directed ...199910481060
the specificity of helicoverpa armigera stunt virus infectivity.helicoverpa armigera stunt virus (hasv) is a member of the tetraviridae family of rna viruses whose replication and expression strategies are not well understood due to the absence of an in vitro cell culture system. we set out to find such a system for hasv by screening an array of 13 insect and 1 mammalian cell culture lines with both virus particle infection and genomic rna transfection. no cell line was found to be permissive for replication, although entry of genomic rna was verified. the a ...199910486228
virions of heliothis armigera entomopoxvirus contain a homologue of the vaccinia vp8 major core antigenic 30 k virion protein of heliothis armigera entomopoxvirus (haepv) has been identified as a homologue of the chordopoxvirus (chpv) vp8 major virion core protein. like its homologue in vaccinia virus, the mature haepv 30 k protein is derived by post-translational cleavage of a precursor at a conserved aga motif. the haepv 30 k protein is the first epv structural virion protein to be described, and elucidation of its characteristics provides evidence for the assumption that morphologica ...199910499447
biological and biochemical relationships between the nucleopolyhedroviruses of mamestra brassicae and heliothis armigera.the multiply embedded nucleopolyhedroviruses (mnpv) originally isolated from mamestra brassicae (german and dutch isolates) and heliothis armigera have been studied comparatively to establish their relatedness, both in terms of biological activity and genomic homology. all three viral isolates replicated in m. brassicae, h. armigera, heliothis zea, and heliothis virescens, resulting in each case in progeny virus that was essentially similar to the inoculum. dose-mortality studies carried out on ...200010631051
molecular cloning and expression of cyp6b8: a xanthotoxin-inducible cytochrome p450 cdna from helicoverpa zea.xanthotoxin, a plant allelochemical, induces alpha-cypermethrin insecticide tolerance in helicoverpa zea (corn earworm); inhibition of tolerance by piperonyl butoxide implicates cytochrome p450 monooxygenases (p450s) in the detoxification of this insecticide. to characterize the xanthotoxin-inducible p450 that might mediate alpha-cypermethrin tolerance in this species, a cdna library prepared from xanthotoxin-induced h. zea fifth instar larvae was screened with cdnas encoding furanocoumarin-meta ...200010646973
insecticidal activity of transgenic tobacco plants expressing both bt and cpti genes on cotton bollworm (helicoverpa armigera).transgenic tobacco plants expressing both bacillus thuringiensis (bt) insecticidal protein and cowpea trypsin inhibitor (cpti) genes was used to evaluate the insecticidal activity on the cotton bollworm (helicoverpa armigera) compared with transgenic tobacco with bt insecticidal protein gene alone. mortality of first to third instar larvae fed on transgenic two genes tobacco for three days was significantly higher than that fed on transgenic bt tobacco. first to fourth instar larvae fed on trans ...199910668128
spindle bodies of heliothis armigera entomopoxvirus develop in structures associated with host cell endoplasmic reticulum.immunoelectron microscopy has shown that morphogenesis of spindle bodies (sb) of heliothis armigera entomopoxvirus involves an iterative process of condensation, aggregation, and crystallization of the major constituent protein (fusolin) within the perinuclear space and endoplasmic reticulum (er) of infected cells and in vesicles derived from er constituents. the er-specific chaperone bip has been observed to be associated with developing sbs at all stages of this process, and it is postulated t ...200010753594
helicoverpa armigera granulovirus interference with progression of h. zea nucleopolyhedrovirus disease in h. zea larvae.capsular proteins from helicoverpa armigera granulovirus (hagv) have previously been shown to enhance h. armigera nucleopolyhedrovirus (hasnpv) infection in h. armigera larvae. yet, hagv and has-npv, as viable viruses, interfered with one another. in our study, we have examined the effects of co-infection of the slow-killing virus hagv with the fast-killing virus helicoverpa zea npv (hzsnpv) on h. zea larvae. the mortality parameter measured was survival time. virus stocks had 50% lethal concent ...200010772322
the interactions between soybean trypsin inhibitor and delta-endotoxin of bacillus thuringiensis in helicoverpa armigera significant difference in larval mortality was observed when a sublethal dose of bacillus thuringiensis (bt) var. kurstaki hd-1 crystal was supplemented with soybean trypsin inhibitor (sti) in the artificial diet fed to helicoverpa armigera in the laboratory, but supplementing a nonlethal dose of crystal with sti in the diet led to a pronounced reduction of larval growth. this concentration of crystal and two lower concentrations of sti alone had no significant effects on larval growth. the r ...200010843832
reverse transcription of a naturally occurring nonretroviral rna produces a precise deletion in the majority of its cdna products.a precise, reproducible deletion made during in vitro reverse transcription of rna2 from the icosahedral positive-stranded helicoverpa armigera stunt virus (tetraviridae) is described. the deletion, located between two hexamer repeats, is a 50-base sequence that includes one copy of the hexamer repeat. only the moloney murine leukemia virus reverse transcriptase and its derivative superscript i, carrying a deletion of the carboxy-terminal rnase h region, showed this response, indicating a templa ...200010868914
enhancement in activity of homologous and heterologous baculoviruses infectious to beet armyworm (lepidoptera: noctuidae) by an optical brightener.the nuclear polyhedrosis virus (npv) from the beet armyworm, spodoptera exigua (hübner) (semnpv), was the most active virus tested against the beet armyworm (lc50 = 4.1 pibs/mm2), followed by nuclear polyhedrosis viruses from the alfalfa looper, autographa californica (speyer) (acmnpv; lc50 = 92.6 pibs/mm2), and the celery looper, anagrapha falcifera (kirby) (afmnpv; lc50 = 195.7 pibs/mm2). in the case of the nuclear polyhedrosis virus from the bollworm, helicoverpa armigera (hübner), lc50s coul ...200010902301
molecular and insecticidal characterization of a bacillus thuringiensis strain isolated during a natural epizootic.a new bacillus thuringiensis strain belonging to the serovar aizawai was isolated from a dead larva of the lepidopteran mythimna loreyi collected in a corn crop in spain during a natural epizootic. this strain, which was named leapi01, was compared with the kurstaki and aizawai strains isolated from dipel(r) and xentari(r), by electron microscopy, sds-page, plasmid pattern, pcr and insecticidal activity. this strain showed similar morphological and biochemical characteristics to the standard str ...200010971764
plant-toxin interactions in transgenic bt cotton and their effect on mortality of helicoverpa armigera (lepidoptera: noctuidae).in australia, transgenic cotton plants expressing the cry1ac gene from bacillus thuringiensis berliner variety kurstaki are less toxic to first-instar helicoverpa armigera (hübner) after the plant is producing fruit. we developed two bioassay methods (leaf mush, leaf disk) to test if the physiological state of the plants explained changes in toxicity and a third method (diet incorporation) was developed to quantify the toxicity of bt leaves when mixed in chickpea diet. cry1ac protein was less to ...200010985045
virus morphogenesis of helicoverpa armigera nucleopolyhedrovirus in helicoverpa zea serum-free suspension culture.helicoverpa armigera single nucleopolyhedrovirus (hasnpv) replication in helicoverpa zea serum-free suspension culture was studied in detail and the sequence of virus morphogenesis was determined by transmission electron microscopy. by 16 h post-infection (p.i.), virus replication was observed in the virogenic stroma by the appearance of nucleocapsids. polyhedron formation was detected by 24 h p.i. and the polyhedron envelope (pe) was completely formed by 72 h p.i. pe morphogenesis of hasnpv is ...200010993944
field evaluation of a slow release pheromone formulation to control the american bollworm, helicoverpa armigera (lepidoptera: noctuidae) in pakistan.trials to control the american bollworm, helicoverpa armigera (hübner) by the technique of mating disruption were carried out in the pakistan province of punjab during the 1996 cotton season. a slow release pvc resin formulation, selibate(r) ha, containing a 97:3 mixture of the major (9z-hexadecenal) and minor (11z-hexadecenal) components of the female sex pheromone of h. armigera was applied at a rate of 40 g active ingredient ha-1 during august 1996. the formulation was applied around the term ...200010996859
population structure of the pestiferous moth helicoverpa armigera in the eastern mediterranean using rapd analysis.the genetic structure of the cotton bollworm, helicoverpa armigera (hübner) (lepidoptera: noctuidae), was studied in the eastern mediterranean. moths were sampled in six locations (five in israel, and one in turkey) and their genetic relationship was analysed using rapd-pcr. three 10-oligonucleotide primers revealed 84 presumptive polymorphic loci that were used to estimate population structure. results reveal low level of genetic distances among israeli and turkish populations. the estimated va ...200011012728
the sequence of the helicoverpa armigera single nucleocapsid nucleopolyhedrovirus genome.the nucleotide sequence of the helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (hasnpv) dna genome was determined and analysed. the circular genome encompasses 131,403 bp, has a g+c content of 39.1 mol% and contains five homologous regions with a unique pattern of repeats. computer-assisted analysis revealed 135 putative orfs of 150 nt or larger; 100 orfs have homologues in autographa californica multicapsid npv (acmnpv) and a further 15 orfs have homologues in other baculoviruses ...200111125177
analysis of the capsid processing strategy of thosea asigna virus using baculovirus expression of virus-like particles.thosea asigna virus (tav), a putative member of the genus betatetravirus of the family tetraviridae, is predicted to have a novel capsid expression strategy compared with other characterized tetraviruses. the capsid precursor protein is cleaved twice to generate three proteins. two of the proteins, l (58.3 kda) and s (6.8 kda), are incorporated into the tav virion. the third, non-structural protein, produced from the n terminus of the precursor protein, is up to 17 kda in size and is of unknown ...200111125178
[the characteristics of bacillus thuringiensis strain ybt833 and its transformants that containing different icp genes].four different transformants were selected by transferring cry1c into bacillus thuringiensis strain ybt833. southern blot and plasmid profiles results all proved that cry1c was transferred into strain ybt833. however, it was found by pcr analysis that transformant ybt833-1 kept all indigenous icp(insecticidal crystal protein) genes of strain ybt833 while transformant ybt833-2 lost cry1ab, and transformant ybt833-3 lost all icp genes. sds-page showed that transformants of ybt833-1, ybt833-2 and y ...200011132501
effect of two granulosis viruses on the activity of the gypsy moth (lepidoptera: lymantriidae) nuclear polyhedrosis virus.two granulosis viruses (gv) were tested as enhancers for the gypsy moth nuclear polyhedrosis virus (ldmnpv). helicoverpa armigera (hübner) cv (hagv) had no detrimental effect upon larval growth and development, but in combination with ldmnpv it reduced both the lc50 and the lt50 for the npv. in addition, the combination also adversely affected the growth and development of gypsy moth larvae. the lc50 of ldmnpv was reduced by as much as 300-fold (hagv at 10(-2) dilution) and the lt50 was reduced ...200011142292
[transfer of cry1c gene into bacillus thuringiensis by electroporation to construct strain with broader insecticidal activity].three transformants were selected by transferring cry1c into bacillus thuringiensis strain ybt1535. plasmid profiles, pcr and southern blot result all proved that cry1c had been transferred into strain ybt1535. bioassay results showed that the transformants of strain ybt1535 displayed significantly higher toxicity against spodoptera exigua than strain ybt1535, but the toxicities against heliothis armigera and plutella xylostella did not rise except transformant ybt1535-2.200011191763
[expression of 2.1 kb enhancin gene fragment from helicoverpa armigera granulosis virus in escherichia coli].the 2.1 kb fragment of enhancin gene from helicoverpa armigera granulosis virus was inserted into vector pqe-30 and expressed successfully in e. coli m15(prep4). the synergy of expression product(p78) on acmnpv against the larvae of plutella xylostella was also studied. the results indicated that the percentage of correct mortality of the larvae increased 27.88%-32.92% in 10 post-infection days.200011191765
carbamate and organophosphate resistance in cotton pests in india, 1995 to 1999.monitoring for organophosphate and carbamate resistance was carried out on five major insect pests of cotton collected from 22 cotton-growing districts across india. resistance was monitored in helicoverpa armigera (hübner) and pectinophora gossypiella (saunders) for the period 1995-1999 and for spodoptera litura (fabricius), earias vittella (fabricius) and bemisia tabaci (gennadius) in a survey conducted during the 1997-98 cropping season. of the 53 field strains of h. armigera, only four were ...200111228586
growth inhibitory and antifeedant activity of extracts from melia dubia to spodoptera litura and helicoverpa armigera larvae.the growth inhibitory activity and deterrency of melia dubia (meliaceae) extracts to spodoptera litura and helicoverpa armigera were investigated. artificial diet bioassays using neonate larvae of both s. litura and h. armigera indicated that dichloroethane (dce) and methanol (me) extracts of m. dubia inhibited growth in a dose dependent manner. dce and me-5ii fractions also resulted in 50% deterrency at concentrations of 22.5 and 16.8 micrograms/cm2 respectively against s. litura larvae in a le ...200011233088
both lymantria dispar nucleopolyhedrovirus enhancin genes contribute to viral potency.enhancins are a group of proteins first identified in granuloviruses (gv) that have the ability to enhance nuclear polyhedrosis virus potency. we had previously identified an enhancin gene (e1) in the lymantria dispar multinucleocapsid nucleopolyhedrovirus (ldmnpv) (d. s. bischoff and j. m. slavicek, j. virol. 71:8133-8140, 1997). inactivation of the e1 gene product within the viral genome lowered viral potency by an average of 2.9-fold. a second enhancin gene (e2) was identified when the entire ...200111507209
[studies on transgenic tobacco plants expressing two kinds of insect resistant genes].a synthetic bt cry1ac gene fussed with a secretary signal coding sequences at 5' end and a modified gna gene were used to construct a plant expression vector pbsgs1m+ and this vector was transferred into tobacco (nicotiana tabacum l.) by agrobacterium-mediated transformation method. results of pcr, southern blot and slot blot analysis indicated that both the chimeric bt cry1ac and gna genes were integrated into the genomes of transformed plants. western blot analysis indicated that at least the ...200111517599
replication-independent assembly of an insect virus (tetraviridae) in plant cells.infectious virions of the insect rna virus helicoverpa armigera stunt virus (hasv; omegatetravirus, tetraviridae) were assembled in cultured plant protoplasts of nicotiana plumbaginifolia in the absence of detectable replication. assembly of the virus, which has not been grown in cell culture, required cotransfection of a dna plasmid expressing the hasv capsid gene in combination with either genomic rna or with dna plasmids carrying the complete cdnas to the two hasv genomic rnas. each cdna was ...200111543656
immunolocalization of odorant-binding proteins in noctuid moths (insecta, lepidoptera).odorant-binding proteins were studied in the noctuid moths agrotis segetum, autographa gamma, helicoverpa armigera, heliothis virescens and spodoptera littoralis using antisera raised against the pheromone-binding protein (pbp) and general odorant-binding protein 2 (gobp2) of antheraea polyphemus (saturniidae). proteins immunoreacting with these antisera were only found on the antennae and pbp and gobp2 could be identified on western blots of males and females of all five species. pbps were pred ...200111555483
aminopeptidase-n from the helicoverpa armigera (hubner) brush border membrane vesicles as a receptor of bacillus thuringiensis crylac delta-endotoxin.brush border membrane vesicles (bbmvs) were prepared from the 2nd instar larvae of helicoverpa armigera. binding of the activated cry1ac of bacillus thuringiensis (bt) toxin was shown by immunoblot. a 120-kda protein was identified as a receptor for the cry1ac type delta-endotoxin. the aminopeptidase-n activity of bbmvs was measured as the hydrolysis of l-leucine p-nitroanilide. the specific activity was 35 units/mg protein. the bbmv preparation also showed low level of alkaline phosphatase acti ...200111683359
effects of the 20-kilodalton helper protein on cry1ac production and spore formation in bacillus thuringiensis.bacillus thuringiensis produces large amounts of various pesticidal proteins during the stationary phase. in order to achieve a high yield and form crystals, some pesticidal proteins require the presence of other proteins. helper protein p20 is required for efficient production of both the cyt1a and cry11a crystal proteins in b. thuringiensis subsp. israelensis. although full-length cry1 protoxins are usually independent in terms of expression and crystallization in b. thuringiensis, in this stu ...200111722880
a uv tolerant mutant of bacillus thuringiensis subsp. kurstaki producing melanin.a uv-resistant mutant (bt-m) of bacillus thuringiensis subsp. kurstaki, producing a dark brown pigment, identified as melanin, was studied. bt-m had higher larvicidity against heliothis armigera than its parent. survival of bt-m spores and their insecticidal activity to irradiation at 254 nm and 366 nm were higher than those of the parent. the only toxic polypeptide produced by bt-m was cry1ac (130 kda); it lost cry1aa, cry2aa, and cry2ab.200211727037
cytochrome p450 and actin genes expressed in helicoverpa zea and helicoverpa armigera: paralogy/orthology identification, gene conversion and evolution.molecular phylogenetic analysis was conducted using conserved cytoplasmic actin and diversified cytochrome p450 (p450) sequences isolated from helicoverpa zea and helicoverpa armigera, two species thought to be closely related based on allozyme analyses. these sequences were compared in turn with published sequences from other insects to gain insight into how different gene families evolve. in bombyx mori and these helicoverpa species, cytoplasmic actin genes are present as a pair of tandemly du ...200211804803
assessment of foreign protein production by recombinant heliothis (helicoverpa) armigera entomopoxviruses in spodoptera frugiperda cells.this report describes the first production of recombinant forms of heliothis (helicoverpa) armigera entomopoxvirus (haepv). these haepvs are engineered at either the spheroidin or fusolin locus, to produce the green fluorescent marker protein (gfp). the growth properties of these recombinant haepvs, in comparison to the parental haepv, were assessed in cultured spodoptera frugiperda sf9 cells. additionally, gfp production by these recombinant haepvs was compared to that of a gfp-expressing recom ...200211807239
[damage and economic threshold of the third generation of cotton bollworm in the yangtze river basin cotton region of jiangsu province].the impact of the third generation of cotton bollworm helicoverpa armigera on shedding of buds and bolls and on bolling was studied by inoculating its larvae to cotton plants. the results showed that the shed rate of buds and bolls damaged by the larvae had the greatest impact on bolling, and its direct path coefficient was up to -0.8917. the larval population density and the number of buds and bolls damaged by the larvae impacted bolling mainly through the damaged shed rate during inoculating s ...200111813442
the larger genomic rna of helicoverpa armigera stunt tetravirus encodes the viral rna polymerase and has a novel 3'-terminal trna-like this paper we report the complete nucleotide sequence of the larger segment (5312 nucleotides) of the bipartite rna genome of helicoverpa armigera stunt tetravirus (hasv). hasv therefore becomes the first member of the tetraviridae, a virus family with a host range restricted to lepidopteran insects, whose genome has been completely sequenced. hasv rna 1 encodes a 187k protein which includes three domains conserved in rna-dependent rna polymerases of rna viruses in the alpha-like superfamily. ...199511831734
comparative analysis of the complete genome sequences of helicoverpa zea and helicoverpa armigera single-nucleocapsid nucleopolyhedroviruses.the complete nucleotide sequence of helicoverpa zea single-nucleocapsid nucleopolyhedrovirus (hzsnpv) has been determined (130869 bp) and compared to the nucleotide sequence of helicoverpa armigera (ha) snpv. these two genomes are very similar in their nucleotide (97% identity) and amino acid (99% identity) sequences. the coding regions are much more conserved than the non-coding regions. in hzsnpv/hasnpv, the 63 open reading frames (orfs) present in all baculoviruses sequenced so far are much m ...200211842262
effect of sublethal concentration of bacillus thuringiensis var. kurstaki on food and developmental needs of the american bollworm, helicoverpa armigera (hübner).effect of sublethal concentration of b. thuringiensis on the first, third, fourth and fifth instar larvae of the american bollworm, h. armigera was investigated to study their response to food consumption, digestion, utilization, and their development till adult formation. the young larvae surviving b. thuringiensis treatment in their first instar and third instar delayed larval period by two to three days, but did not consume more food as compared to control. however, they showed higher digesti ...200111906106
phenotypic and genotypic analysis of helicoverpa armigera nucleopolyhedrovirus serially passaged in cell culture.rapid accumulation of few polyhedra (fp) mutants was detected during serial passaging of helicoverpa armigera nucleopolyhedrovirus (hasnpv) in cell culture. 100% fp infected cells were observed by passage 6. the specific yield decreased from 178 polyhedra per cell at passage 2 to two polyhedra per cell at passage 6. the polyhedra at passage 6 were not biologically active, with a 28-fold reduction in potency compared to passage 3. electron microscopy studies revealed that very few polyhedra were ...200211907345
in-season changes in resistance to insecticides in helicoverpa armigera (lepidoptera: noctuidae) in india.discriminating doses of fenvalerate, cypermethrin, quinalphos, and endosulfan were determined with an insecticide-susceptible helicoverpa armigera (hübner) strain. in-season changes in insecticide resistance were monitored with discriminating dose assays at weekly intervals throughout the cropping season for 6 yr from 1993 to 1999 in central india. resistance to pyrethroids was high throughout all seasons. resistance to 0.75 microg of quinalphos was consistent, with seasonal averages ranging fro ...200211942748
efficient method to generate homologous recombinant baculovirus genomes in e. we describe a convenient method to generate homologous recombinant baculoviral genomes in e. coli. the recombination takes place with the aid of recombination enzymes provided by the phage lambda red system between a bacmid (a baculoviral genome that can replicate in bacteria) and a linear fragment. proof of concept was provided when the cathepsin gene (v-cath) of the helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (hasnpv) was replaced by the chloramphenicol resistance gene ( ...200211962600
contents of cry genes and insecticidal toxicity of bacillus thuringiensis strains from terrestrial and aquatic habitats.two bacillus thuringiensis collections from terrestrial and aquatic habitats were compared in order to study the possible interrelationships between habitat and biological characteristics (serovar, cry genes content and toxicity).200211966916
trichoplusia ni gloverin, an inducible immune gene encoding an antibacterial insect using differential display pcr, we obtained a cdna clone encoding a gloverin homologue from the cabbage looper, trichoplusia ni. the expression of the gene was induced by bacterial infections. the gene codes for a 174 amino acid residue protein, including a signal sequence and a prosegment. the deduced mature protein is 14 kda and shows 58% and 49% identity to p2 from helicoverpa armigera and to hyalophora gloveri gloverin, respectively. the protein was detected in hemolymph and hemocytes fro ...200212044496
the expression of a mammalian proteinase inhibitor, bovine spleen trypsin inhibitor in tobacco and its effects on helicoverpa armigera larvae.the cdna for bovine spleen trypsin inhibitor (si), a homologue of bovine pancreatic trypsin inhibitor (bpti), including the natural mammalian presequence was expressed in tobacco using agrobacterium tumefaciens-mediated transformation. stable expression required the n-terminal targeting signal presequence although subcellular localization was not proven. si was found to exist as two forms, one coinciding with authentic bpti on western blots and the second marginally larger due to retention of th ...200212054350
avidin expressed in transgenic tobacco leaves confers resistance to two noctuid pests, helicoverpa armigera and spodoptera litura.fertile transgenic tobacco plants with leaves expressing avidin in the vacuole have been produced and shown to halt growth and cause mortality in larvae of two noctuid lepidopterans, helicoverpa armigera and spodoptera litura. late first instar h. armigera larvae and neonate (< 12-h-old) s. litura larvae placed on leaves excised from t0 tobacco expressing avidin at 3.1-4.6 microm (micromoles/kg of fresh leaf tissue) had very poor growth over their first 8 days on the leaves, significant numbers ...200212054352
resistance monitoring of helicoverpa armigera (lepidoptera noctuidae) to bacillus thuringiensis insecticidal protein in china.sensitivities of helicoverpa armigera (hübner) field populations to bacillus thuringiensis (bt) insecticidal protein crylac were monitored during 1998-2000 in china. a total of 41 strains was sampled, and most of them were collected from bt cotton planting regions. the range of ic50 values (concentration producing 50% inhibition of larval development to third instar) among different populations in 1998,1999, and 2000 were 0.020-0.105 microg/ml, 0.016-0.099 microg/ml, and 0.016-0.080 microg/ml, r ...200212216827
evaluation of the natural refuge function for helicoverpa arnigera (lepidoptera: noctuidae) within bacillus thuringiensis transgenic cotton growing areas in north china.the density of helicoverpa armigera (hübner) populations on bacillus thuringiensis berliner (bt) transgenic cotton, corn, peanut, and soybean; differences in its development on bt cotton and common (nontransgenic) cotton; and the potential for mating among populations from bt cotton fields and other crop fields were investigated in the suburbs of xinxiang city (henan province) and langfang city (hebei province) in the southern and northern parts of north china, respectively. although development ...200212216828
nucleotide sequence analysis of hasnpv protein kinase.the protein kinase gene of helicoverpa armigera single nucleocapsid nuclear polyhedrosis virus (hasnpv) has been cloned and sequenced. it is located approximately 1.25 kb downstream of the polyhedrin gene. the predicted molecular mass of this 267 amino acid protein (havpk) is 31 kd. havpk shows a 43.0% amino acid homology to vpk from lymantria dispar multinucleocapsid nuclear polyhedrosis virus (ldmnpv) and a 39.0% homology to pk-1 from autographa californica multinucleocapsid nuclear polyhedros ...199712219213
toxicity of bacillus thuringiensis insecticidal proteins for helicoverpa armigera and helicoverpa punctigera (lepidoptera: noctuidae), major pests of cotton.the susceptibilities of the major pests of cotton in australia, helicoverpa armigera and helicoverpa punctigera, to some insecticidal proteins from bacillus thuringiensis were tested by bioassay. a commercial formulation, dipel, and individual purified insecticidal proteins were tested. h. armigera was consistently more tolerant to b. thuringiensis insecticidal proteins than was h. punctigera, although both were susceptible to only a limited range of these proteins. only cry1ab, cry1ac, cry2aa, ...200212234543
cloning and characterization of an insecticidal crystal protein gene from bacillus thuringiensis subspecies kenyae.a sporulating culture of bacillus thuringiensis subsp. kenyae strain hd549 is toxic to larvae of lepidopteran insect species such as spodoptera litura, helicoverpa armigera and phthorimaea operculella, and a dipteran insect, culex fatigans. a 1.9-kb dna fragment, pcr-amplified from hd549 using cryii-gene-specific primers, was cloned and expressed in e. coli. the recombinant protein produced 92% mortality in first-instar larvae of spodoptera litura and 86% inhibition of adult emergence in phthori ...200212357073
establishment of two new cell lines from bombyx mori (l.) (lepidoptera: bombycidae) & their susceptibility to baculoviruses.lepidopteran cell cultures and baculovirus expression vector systems are becoming popular due to their potential applications in biotechnology especially for the expression of foreign proteins. efforts were made to develop new, indigenous, cell lines from bombyx mori larvae and pupae.200212362558
infection of its lepidopteran host by the helicoverpa armigera stunt virus (tetraviridae).techniques of microscopy and histopathology were employed to study the positive-sense, single-stranded rna virus, the helicoverpa armigera stunt virus (hasv; omegatetravirus, tetraviridae) infecting its caterpillar host. infection of the virus per os during the first three instars of larval development is virulent and leads to rapid stunting and mortality. in contrast, no detectable symptoms occur in later larval development, signifying a high degree of developmental resistance. a quantitative s ...200212383435
a new cell line from the embryonic tissue of helicoverpa armigera hbn. (lepidoptera: noctuidae).a new cell line from the embryonic tissue of helicoverpa armigera was established and designated as niv-ha-197. it was maintained in tnm-fh medium supplemented with 10% fetal bovine serum. the cell line at passage 20 had a heterogeneous population of cells consisting of mainly epithelial-like cells (70%), followed by fibroblast-like (27%), and multinucleated giant (3%) cells. the chromosome number ranged from 45 to 185. the growth curve at passage 40 showed a fivefold increase in cell number wit ...200212418922
first steps to improve cotton crop management in thailand.thai cotton growers yearly face serious pest problems consisting of heavy infestation associated with resistance to pesticides leading to expensive and harmful pest control practices. thanks to a multi discipline research work carried out from 1991 to 1996, a decision-oriented model for cotton crop management was developed and compared to farmers' practices during the 1988 cotton growing season 1998 in klang hat district, thailand. this model, based on plant monitoring, involved a new cotton cul ...200112425063
recombinantly expressed isoenzymic aminopeptidases from helicoverpa armigera (american cotton bollworm) midgut display differential interaction with closely related bacillus thuringiensis insecticidal proteins.several investigators have independently identified membrane-associated aminopeptidases in the midgut of insect larvae as the initial interacting ligand to the insecticidal crystal proteins of bacillus thuringiensis. though several isoenzymes of aminopeptidases have been identified from the midgut of an insect and their corresponding cdna cloned, only one of the isoform has been expressed heterologously and studied for its binding to cry toxins. here we report the cloning and expression of two a ...200312441000
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