| bacillus thuringiensis insecticidal crystal proteins affect lifespan and reproductive performance of helicoverpa armigera and spodoptera exigua adults. | being delivered as sprays or expressed in plant, bacillus thuringiensis (bt) crystalline proteins (cry toxins) display insecticidal activities against numerous lepidopteran, dipteran, and coleopteran larvae. comparative study of toxicities of bt cry toxins between larvae and adults may afford important new insights into the interactions of the toxins with receptor proteins in host insect, and represent intriguing targets for the control of insect pests. however, the effectiveness of bt cry toxin ... | 2013 | 23786046 |
| use of a pooled clone method to isolate a novel bacillus thuringiensis cry2a toxin with activity against ostrinia furnacalis. | a pooled clone method was developed to screen for cry2a genes. this metagenomic method avoids the need to analyse isolated bacillus thuringiensis strains by performing gene specific pcr on plasmid-enriched dna prepared from a pooled soil sample. using this approach the novel holotype gene cry2ah1 was cloned and characterized. the toxin gene was over-expressed in escherichia coli rosetta (de3) and the expressed toxin accumulated in both the soluble and insoluble fractions. the soluble cry2ah1 was ... | 2013 | 23711413 |
| constructing bacillus thuringiensis strain that co-expresses cry2aa and chitinase. | a triple recombineering technique was used with plasmid pht315 to produce phtec, a construct carrying chitinase and cry2aa genes from bacillus thuringiensis subsp. kurstaki 4.0718. transformation of wild-type b. thuringiensis strain hd73 and the acrystalliferous strain cry-b with phtec resulted in the recovery of recombinant strains that expressed cry2aa as cubic crystals in the cell pellet and soluble chitinase protein. the toxicity of hd73 (phtec) against helicoverpa armigera larvae increased ... | 2013 | 23515891 |
| characterization of cry9da4, cry9eb2, and cry9ee1 genes from bacillus thuringiensis strain t03b001. | three cry9 genes, cry9da4, cry9eb2, and cry9ee1, were cloned from bacillus thuringiensis strain t03b001 using a high-resolution melting analysis method. all three cry9 genes were overexpressed in escherichia coli rosetta (de3), and the expressed products cry9eb2 and cry9ee1 were shown to be toxic to plutella xylostella and ostrinia furnacalis, but not to helicoverpa armigera or colaphellus bowringi. the bioassay of cry9eb2 and cry9ee1 against cry1ac-resistant p. xylostella strains indicated that ... | 2013 | 23455566 |
| influence of oxalic and malic acids in chickpea leaf exudates on the biological activity of cryiac towards helicoverpa armigera. | efforts are being made to express toxin genes from the bacterium, bacillus thuringiensis (bt) in chickpea for minimizing the losses due to the pod borer, helicoverpa armigera. however, there is an apprehension that acidic exudates in chickpea leaves may influence the protoxin-toxin conversion in the insect midgut, and thus, reduce the efficacy of bt toxins. therefore, we studied the influence of organic acids (oxalic acid and malic acid) present in the trichome exudates of chickpea on the biolog ... | 2013 | 23391855 |
| non-recessive bt toxin resistance conferred by an intracellular cadherin mutation in field-selected populations of cotton bollworm. | transgenic crops producing bacillus thuringiensis (bt) toxins have been planted widely to control insect pests, yet evolution of resistance by the pests can reduce the benefits of this approach. recessive mutations in the extracellular domain of toxin-binding cadherin proteins that confer resistance to bt toxin cry1ac by disrupting toxin binding have been reported previously in three major lepidopteran pests, including the cotton bollworm, helicoverpa armigera. here we report a novel allele from ... | 2012 | 23285292 |
| cloning, characterization, and expression of a new cry1ab gene from dor bt-1, an indigenous isolate of bacillus thuringiensis. | a new cry1ab gene was cloned from the promising local isolate, dor bt-1, a bacillus thuringiensis strain isolated from castor semilooper (achaea janata l.) cadavers from castor bean (ricinus communis l.) field. the nucleotide sequence of the cloned cry1ab gene indicated that the open reading frame consisted of 3,465 bases encoding a protein of 1,155 amino acid residues with an estimated molecular weight of 130 kda. homology comparisons revealed that the deduced amino acid sequence of cry1ab had ... | 2013 | 23224937 |
| cis-acting motifs in artificially synthesized expression cassette leads to enhanced transgene expression in tomato (solanum lycopersicum l.). | efficacy of artificial synthetic expression modules was compared with native camv35s and decamv35s promoter in transgenic tomato developed by agrobacterium-mediated transformation. the promoters under trial were camv35s-mec (pcami), camv35s (pcamii), decamv35s (pcamiii), synthetic minimal expression cassette (pmec), complete expression cassette (pcec), double enhancer expression cassette (pdec) and triple enhancer expression cassette (ptec) for driving the uida gene for β-glucuronidase (gus) act ... | 2012 | 23137727 |
| the halo effect: suppression of pink bollworm on non-bt cotton by bt cotton in china. | in some previously reported cases, transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt) have suppressed insect pests not only in fields planted with such crops, but also regionally on host plants that do not produce bt toxins. here we used 16 years of field data to determine if bt cotton caused this "halo effect" against pink bollworm (pectinophora gossypiella) in six provinces of the yangtze river valley of china. in this region, the percentage of cotton hectares pl ... | 2012 | 22848685 |
| diverse genetic basis of field-evolved resistance to bt cotton in cotton bollworm from china. | evolution of pest resistance reduces the efficacy of insecticidal proteins from bacillus thuringiensis (bt) used in sprays or in transgenic crops. although several pests have evolved resistance to bt crops in the field, information about the genetic basis of field-evolved resistance to bt crops has been limited. in particular, laboratory-selected resistance to bt toxin cry1ac based on recessive mutations in a gene encoding a toxin-binding cadherin protein has been identified in three major cotto ... | 2012 | 22689968 |
| early detection of field-evolved resistance to bt cotton in china: cotton bollworm and pink bollworm. | transgenic crops producing bacillus thuringiensis (bt) toxins kill some major insect pests, but pests can evolve resistance and thereby reduce the effectiveness of such bt crops. the main approach for slowing pest adaptation to bt crops uses non-bt host plants as "refuges" to increase survival of susceptible pests. to delay evolution of pest resistance to cotton producing bt toxin cry1ac, several countries have required refuges of non-bt cotton, while farmers in china have relied on "natural" re ... | 2012 | 22537835 |
| specific binding of radiolabeled cry1fa insecticidal protein from bacillus thuringiensis to midgut sites in lepidopteran species. | cry1fa insecticidal protein was successfully radiolabeled with (125)i-na. specific binding to brush border membrane vesicles was shown for the lepidopteran species ostrinia nubilalis, spodoptera frugiperda, spodoptera exigua, helicoverpa armigera, heliothis virescens, and plutella xylostella. homologous competition assays were performed to obtain equilibrium binding parameters (k(d) [dissociation constant] and r(t) [concentration of binding sites]) for these six insect species. | 2012 | 22447600 |
| assessing the role of non-cotton refuges in delaying helicoverpa armigera resistance to bt cotton in west africa. | non-cotton host plants without bacillus thuringiensis (bt) toxins can provide refuges that delay resistance to bt cotton in polyphagous insect pests. it has proven difficult, however, to determine the effective contribution of such refuges and their role in delaying resistance evolution. here, we used biogeochemical markers to quantify movement of helicoverpa armigera moths from non-cotton hosts to cotton fields in three agricultural landscapes of the west african cotton belt (cameroon) where bt ... | 2012 | 25568029 |
| 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 ... | 2012 | 24371572 |
| effect of different additives on the persistence and insecticidal activity of native strains of bacillus thuringiensis. | the persistence and insecticidal activity of native strains of bacillus thuringiensis was evaluated in formulations containing different additives such as arrow-root powder, carboxy methyl cellulose (cmc), gum acacia, non-food grade (nfg) starch, and soluble starch. persistence of b. thuringiensis varied with different additives used in the formulations. among the different additives used, nfg starch provided maximum protection to b. thuringiensis and native strain 42 showed maximum persistence ... | 2007 | 23100638 |
| the efficacy of beauveria bassiana, jasmonic acid and chlorantraniliprole on larval populations of helicoverpa armigera in chickpea crop ecosystems. | a robust integrated pest management (ipm) programme is needed to reduce the use of insecticides in controlling helicoverpa armigera. therefore, a 2 year field study was conducted to evaluate the use of alternative control measures (biochemical use) for h. armigera relative to exclusively using chemical insecticides. the entomopathogenic fungus beauveria bassiana, jasmonic acid and the insecticide chlorantraniliprole were each applied twice during the chickpea growing season. | 2017 | 27101405 |
| improvement in the uv resistance of baculoviruses by displaying nano-zinc oxide-binding peptides on the surfaces of their occlusion bodies. | the sensitivity of baculoviruses to uv radiation severely limits their large-scale application as biological insecticides. the polyhedron envelope of a baculovirus, which is composed of carbohydrate and polyhedron envelope protein (pep), is a significant structure for the stability and persistence of occlusion bodies (obs) under environmental conditions. the results of this study revealed that the rough pitted surface phenotype of a pep-null autographa californica multiple nucleopolyhedrovirus ( ... | 2015 | 25895092 |
| molecular cloning and characterization of α-amylase/subtilisin inhibitor from rhizome of ligusticum chuanxiong. | to clone and characterize a novel bi-functional α-amylase/subtilisin inhibitor (lasi) from the rhizome of ligusticum chuanxiong, a traditional chinese medicine. | 2017 | 27752792 |
| artificial mirna-mediated silencing of ecdysone receptor (ecr) affects larval development and oogenesis in helicoverpa armigera. | the insect pests are real threat to farmers as they affect the crop yield to a great extent. the use of chemical pesticides for insect pest control has always been a matter of concern as they pollute the environment and are also harmful for human health. bt (bacillus thuringensis) technology helped the farmers to get rid of the insect pests, but experienced a major drawback due to the evolution of insects gaining resistance towards these toxins. hence, alternative strategies are high on demand t ... | 2016 | 27476930 |
| bacterial expression and kinetic analysis of carboxylesterase 001d from helicoverpa armigera. | carboxylesterasesare an important class of detoxification enzymes involved in insecticide resistance in insects. a subgroup of helicoverpa armigera esterases, known as clade 001, was implicated in organophosphate and pyrethroid insecticide resistance due to their overabundance in resistant strains. in this work, a novel carboxylesterasegene 001d of h. armigera from china was cloned, which has an open reading frame of 1665 nucleotides encoding 554 amino acid residues. we used a series of fusion p ... | 2016 | 27049381 |
| identification of a thioredoxin peroxidase gene involved in resistance to nucleopolyhedrovirus infection in helicoverpa armigera with rna interference. | thioredoxin peroxidases (tpxs) play a crucial role in protection against oxidative damage in several insect species. however, studies on the characteristics and functions of tpxs in helicoverpa armigera are lacking. in this study, a novel 2-cys tpx gene from h. armigera (hatpx) was identified. sequence analysis revealed that hatpx is highly conserved and shares two catalysis regions (vcp) with other insect species. hatpx mrna was found to be expressed in an age-dependent manner and was ubiquitou ... | 2015 | 26238928 |
| the endoparasitoid campoletis chlorideae induces a hemolytic factor in the herbivorous insect helicoverpa armigera. | although lysis of invading organisms is a major innate form of immunity used by invertebrates, it remains unclear whether herbivorous insects have hemolysin or not. to address this general question, we tested the hemolytic (hl) activity of the hemolymph and tissue extracts from various stages of the polyphagous insect helicoverpa armigera (hübner) against the erythrocytes from chicken, duck, and rabbit. an hl activity was identified in the hemolymph of h. armigera larvae. further studies demonst ... | 2015 | 25929852 |
| rab3 is involved in cellular immune responses of the cotton bollworm, helicoverpa armigera. | rab3, a member of the rab gtpase family, has been found to be involved in innate immunity. however, the precise function of this gtpase in innate immunity remains unknown. in this study, we identified a rab3 gene (ha-rab3) from the cotton bollworm, helicoverpa armigera and studied its roles in innate immune responses. expression of ha-rab3 was upregulated in the hemocytes of h. armigera larvae after the injection of escherichia coli or chromatography beads. the dsrna-mediated knockdown of ha-rab ... | 2015 | 25662061 |
| molecular characterization of a peptidoglycan recognition protein from the cotton bollworm, helicoverpa armigera and its role in the prophenoloxidase activation pathway. | peptidoglycan recognition proteins (pgrps), which are evolutionarily conserved from invertebrates to vertebrates, function as pattern-recognition and effector molecules in innate immunity. in this study, a pgrp (hapgrp-a) from the cotton bollworm, helicoverpa armigera was identified and characterized. sequence analysis indicated that hapgrp-a is not an amidase-type pgrp. increased levels of hapgrp-a mrna were observed in the fat body and hemocytes of h. armigera larvae following the injection of ... | 2015 | 25659083 |
| isolation, structure modeling and function characterization of a trypsin inhibitor from cassia obtusifolia. | a trypsin inhibitor gene (coti1) from cassia obtusifolia was isolated and the deduced amino acid sequence was attributed to the kunitz-type trypsin inhibitor. the recombined coti1, expressed in e. coli, exhibited strong inhibitory effect on bovine trypsin and trypsin-like proteases from helicoverpa armigera, spodoptera exigua, and spodoptera litura. coti1 thus presents insecticidal properties that may be useful for the genetic engineering of plants. leu84, arg86 and thr88 were predicted as three ... | 2015 | 25479703 |
| identification and functional characterization of a peptidoglycan recognition protein from the cotton bollworm, helicoverpa armigera. | peptidoglycan recognition proteins (pgrps) specifically bind to peptidoglycans, and play crucial roles as pattern recognition receptors (prrs) in mediating innate immune responses. in this study, we identified and characterized a pgrp (hapgrp-d) from the cotton bollworm, helicoverpa armigera. sequence analysis indicated that hapgrp-d is an amidase-type pgrp. expression of hapgrp-d was upregulated in the hemocytes of h. armigera larvae after injecting gram-negative escherichia coli, gram-positive ... | 2014 | 25044262 |
| characterization of nadph-cytochrome p450 reductase gene from the cotton bollworm, helicoverpa armigera. | a complete cdna encoding the nadph-cytochrome p450 reductase (hacpr) and its genomic sequence from the cotton bollworm helicoverpa armigera were cloned and sequenced. the open reading frame of hacpr codes for a protein of 687 amino acid residues with a calculated molecular mass of 77.4kda. the hacpr gene spans over 11 kb and its coding region is interrupted by 11 introns. hacpr is ubiquitously expressed in various tissues and at various stages of development. escherichia coli produced hacpr enzy ... | 2014 | 24768738 |
| revisiting rubisco as a protein substrate for insect midgut proteases. | gene fragments encoding the large subunit (ls) of rubisco (rbcl) were cloned from various species of host plants of phytophagous lepidoptera and expressed as recombinant proteins in escherichia coli. recombinant rbcls were compared among each other along with casein and native rubisco as proteinaceous substrates for measuring total midgut protease activities of fourth instar larvae of helicoverpa armigera feeding on casein, pieris brassicae feeding on cauliflower, and antheraea assamensis feedin ... | 2014 | 24338735 |
| srp gene is required for helicoverpa armigera prophenoloxidase activation and nodulation response. | srp gene was first identified from the fall webworm, hyphantria cunea as one of genes up-regulated after bacteria injection. a rent study in spodoptera litura showed that stress-induced elevation of srp expression highly correlates with reduced feeding activities and growth retardation of larvae. in this study, we identified a srp gene from the cotton bollworm, helicoverpa armigera, namely ha-srp, and studied its precise roles in insect immunity. expressions of ha-srp were upregulated in h. armi ... | 2014 | 24333441 |
| antibody-based detection of alkaline phosphatase in lepidopteran insects (lepidoptera: noctuidae). | alkaline phosphatase (alp) of helicoverpa armigera hub. (lepidoptera; noctuidae) (genbank accession no. eu729322) was cloned and expressed. the target gene h.a-alp, having an open reading frame of 1608 bp, was reverse-transcribed from cdna by the polymerase chain reaction. the open reading frame of the target gene was cloned into the pet-32a expression vector to obtain recombinant protein in escherichia coli de-3 cells for the subsequent production of polyclonal antibody. new zealand white rabbi ... | 2013 | 24222217 |
| characterization of a novel chitinase, dkchi, from dendrolimus kikuchii nucleopolyhedrovirus. | dendrolimus kikuchii matsumura nucleopolyhedrovirus (dknpv) is a novel nucleopolyhedrovirus strain that has exhibited high potential as biological control agent against d. kikuchii. in this work, a 1755-bp dkchi gene with sequence homology to a chitinase gene was cloned from the genomic dna of dknpv using a dna fragment library. the dkchi gene, encoding 558 residues protein with a predicted mass of 61.6 kda, was expressed at high levels in escherichia coli and purified by affinity chromatography ... | 2013 | 23827975 |
| silencing the hahr3 gene by transgenic plant-mediated rnai to disrupt helicoverpa armigera development. | rna interference (rnai) caused by exogenous double-stranded rna (dsrna) has developed into a powerful technique in functional genomics, and to date it is widely used to down-regulate crucial physiology-related genes to control pest insects. a molt-regulating transcription factor gene, hahr3, of cotton bollworm (helicoverpa armigera) was selected as the target gene. four different fragments covering the coding sequence (cds) of hahr3 were cloned into vector l4440 to express dsrnas in escherichia ... | 2013 | 23630449 |
| silencing of cytochrome p450 cyp6b6 gene of cotton bollworm (helicoverpa armigera) by rnai. | rna interference (rnai) induced through double-stranded rna (dsrna) has been used widely to study gene function in insects. in this paper we demonstrate the efficacy of rnai in the cotton bollworm, helicoverpa armigera. using cyp6b6 as the target gene, which is expressed in the fat baby and midgut of the lepidopteran pest h. armigera, we constructed the vector which expressed dsrna of cyp6b6. northern blot analysis showed that dsrna expressed in the escherichia coli (ht115) was target gene. the ... | 2013 | 23590813 |
| effects of a new microbial α-amylase inhibitor protein on helicoverpa armigera larvae. | a new microbial α-amylase inhibitor gene was cloned and characterized. the encoded, recombinant, α-amylase inhibitor protein was induced and expressed by isopropyl β-d-1-thiogalactopyranoside (iptg) in escherichia coli m15 cells. the effects of the α-amylase inhibitor protein on helicoverpa armigera larvae were studied. compared to the control, the weight of h. armigera larvae fed the diet with recombinant α-amylase inhibitor protein added at a concentration of 20 μg/g was reduced by 49.8%. the ... | 2013 | 23432599 |
| identification and characterization of two peptidoglycan recognition proteins with zinc-dependent antibacterial activity from the cotton bollworm, helicoverpa armigera. | peptidoglycan recognition proteins (pgrps) specifically bind to peptidoglycan and play an important role in the innate immune responses as pattern recognition receptors (prrs). here we identified and characterized two pgrps (hapgrp-b and hapgrp-c) from the cotton bollworm, helicoverpa armigera. the comparative analysis indicated that five amino acids which are required for t7 lysozyme zn(2+) binding and amidase activity are conserved in hapgrp-b and hapgrp-c, suggesting that the two pgrps are me ... | 2013 | 23295246 |
| the characterization of sapin2b, a plant trichome-localized proteinase inhibitor from solanum americanum. | proteinase inhibitors play an important role in plant resistance of insects and pathogens. in this study, we characterized the serine proteinase inhibitor sapin2b, which is constitutively expressed in solanum americanum trichomes and contains two conserved motifs of the proteinase inhibitor ii (pin2) family. the recombinant sapin2b (rsapin2b), which was expressed in escherichia coli, was demonstrated to be a potent proteinase inhibitor against a panel of serine proteinases, including subtilisin ... | 2012 | 23203117 |
| molecular cloning and recombinant expression of cytochrome p450 cyp6b6 from helicoverpa armigera in escherichia coli. | the cytochrome p450 s play a significant role in the detoxification of plant allelochemicals and synthetic insecticides in lepidoptera. in the cotton bollworm helicoverpa armigera, 2-tridecanone and quercetin can induce p450-dependent monooxygenase activity increased, to further the characterization of p450, the cyp6b6 of cotton bollworm (h. armigera) was cloned, sequenced and expressed in pmal-p2x vector and expressed in escherichia coli. the deduced amino acid sequences of cytochrome p450 in t ... | 2013 | 23096085 |
| characterization of three pheromone-binding proteins (pbps) of helicoverpa armigera (hübner) and their binding properties. | three pheromone-binding proteins of helicoverpa armigera were cloned and expressed in escherichia coli. in order to characterize their physiological properties, ligand-binding experiments were performed using five biologically relevant substances including sex pheromones and interspecific signals. the results showed that one of the pheromone-binding proteins, harmpbp1, binds strongly to each of the two principal pheromone components of h. armigera, (z)-11-tetradecenal and (z)-9-hexadecenal, but ... | 2012 | 22549127 |
| expression profiles of six novel c-type lectins in response to bacterial and 20e injection in the cotton bollworm (helicoverpa armigera). | c-type lectins can act as pattern recognition receptors (prrs) and play an important role in innate immunity. two c-type lectins (hactl1 and hactl2) have been previously identified in the cotton bollworm (helicoverpa armigera). here we isolate six c-type lectins from h. armigera (hactl3, 4, 5, 6, 7 and 8). all six new hactls encode a signal peptide (or partial signal peptide) and complete tandem carbohydrate-recognition domains (crds). hactl4, 5, 6, 7 and 8 mrna increased in the fat body after i ... | 2012 | 22516747 |
| characterization and expression of a cecropin-like gene from helicoverpa armigera. | a cdna encoding a cecropin-like antibacterial peptide was obtained by rt-pcr from cotton budworm (helicoverpa armigera). the cloned cdna consists of 773 nucleotides with a 192 bp open reading frame encoding a peptide of 63 aa, which is comprised of a 21 aa signal peptide and a 42 amino acids mature peptide. the amino acid sequence of the mature peptide is highly similar to those d-type cecropins. the peptide was named as hacd. rt-pcr revealed that the transcript of hacd gene was inducible and co ... | 2007 | 17900955 |
| expression and purification of virus like particles (vlps) of foot-and-mouth disease virus in eri silkworm (samia cynthia ricini) larvae. | foot-and-mouth disease (fmd) is a highly contagious viral disease, which causes severe economic loss to livestock. virus like particles (vlps) produced by recombinant dna technology are gaining importance because of their immunogenic properties and safety in developing a new vaccine for fmd. in the present study, a practical and economically feasible approach of expression, purification and characterization of vlps of fmdv in eri silkworm (samia cynthia ricini) larvae was described. although thr ... | 2016 | 26925448 |
| chemical profile and defensive function of the latex of euphorbia peplus. | plant latex is an endogenous fluid secreted from highly specialized laticifer cells and has been suggested to act as a plant defense system. the chemical profile of the latex of euphorbia peplus was investigated. a total of 13 terpenoids including two previously unknown diterpenoids, (2s*,3s*,4r*,5r*,6r*,8r*,l1r*,13s*,14s*,15r*, 16r*)-5,8,15-triacetoxy-3-benzoyloxy-11,16-dihydroxy-9-oxopepluane and (2r*,3r*, 4s*,5r*,7s*,8s*,9s*,l3s*,14s*,15r*)-2,5,8,9,14-pentaacetoxy-3-benzoyloxy-15-hydroxy-7-is ... | 2017 | 28062071 |
| relationships of helicoverpa armigera, ostrinia nubilalis and fusarium verticillioides on mon 810 maize. | mon 810 maize was developed against ostrinia nubilalis and is suggested to indirectly decrease fusarium spp. infestation in maize ears. to evaluate this effect, co-occurrence of insect and fungal pests on mon 810 maize was studied. during 2009, exceptionally high maize ear infestation occurred in julianna-major (hungary). from investigation of some thousands of maize ears, the majority of the larval damage originated from helicoverpa armigera larvae, while o. nubilalis larvae contributed signifi ... | 2011 | 26467495 |
| binding and entry of a non-enveloped t=4 insect rna virus is triggered by alkaline ph. | tetraviruses are small, non-enveloped, rna viruses that exclusively infect lepidopteran insects. their particles comprise 240 copies of a single capsid protein precursor (cp), which undergoes autoproteolytic cleavage during maturation. the molecular mechanisms of capsid assembly and maturation are well understood, but little is known about the viral infectious lifecycle due to a lack of tissue culture cell lines that are susceptible to tetravirus infection. we show here that binding and entry of ... | 2016 | 27614703 |
| an encapsidated viral protein and its role in rna packaging by a non-enveloped animal rna virus. | alphatetraviruses are small (+) ssrna viruses with non-enveloped, icosahedral, t=4 particles that assemble from 240 copies of a single capsid protein precursor. this study is focused on the mechanisms underlying selection and packaging of genomic vrnas by helicoverpa armigera stunt virus. we demonstrate that the viral protein, p17, is packaged at low levels (between 4 and 8 copies per capsid) raising the possibility of icosahedral asymmetry in wild-type particles. p17 promotes packaging of vrna2 ... | 2015 | 25577149 |
| providence virus (family: carmotetraviridae) replicates vrna in association with the golgi apparatus and secretory vesicles. | providence virus (prv) is the sole member of the family carmotetraviridae (formerly tetraviridae) sharing the characteristic t=4 capsid architecture with other tetravirus families. despite significant structural similarities, prv differs from other tetraviruses in terms of genome organization, non-structural protein sequence and regulation of gene expression. in addition, it is the only tetravirus that infects tissue culture cells. previous studies showed that in persistently infected helicoverp ... | 2013 | 23343628 |
| membrane targeting of an alpha-like tetravirus replicase is directed by a region within the rna-dependent rna polymerase domain. | the members of the family tetraviridae are small positive-sense insect rna viruses that exhibit stringent host specificity and a high degree of tissue tropism, suggesting that complex virus-host interactions are likely to occur during infection and viral replication. the alpha-like replicase of helicoverpa armigera stunt virus (hasv) (genus omegatetravirus) has been proposed to associate with membranes of the endocytic pathway, which is similar to semliki forest virus, sindbis virus and rubella ... | 2012 | 22535773 |
| phylogenetic position and replication kinetics of heliothis virescens ascovirus 3h (hvav-3h) isolated from spodoptera exigua. | insect-specific ascoviruses with a circular genome are distributed in the usa, france, australia and indonesia. here, we report the first ascovirus isolation from spodoptera exigua in hunan, china. dna-dna hybridization to published ascoviruses demonstrated that the new china ascovirus isolate is a variant of heliothis virescens ascovirus 3a (hvav-3a), thus named hvav-3h. we investigated the phylogenetic position, cell infection, vesicle production and viral dna replication kinetics of hvav-3h, ... | 2012 | 22792245 |
| oral administration of tat-ptd-diapause hormone fusion protein interferes with helicoverpa armigera (lepidoptera: noctuidae) development. | diapause hormone (dh), which can terminate diapause in helicoverpa armigera hübner (lepidoptera: noctuidae), has shown promise as a pest control method. however, the main challenge in using dh as an insecticide lies in achieving effective oral delivery, since the peptide may be degraded by digestive enzymes in the gut. to improve the efficacy of oral dh application, the clostera anastomosis (l.) (lepidoptera: notodontidae) diapause hormone (cadh) was fused to the protein transduction domain (ptd ... | 2015 | 26320262 |
| fitness costs to helicoverpa armigera after exposure to sub-lethal concentrations of metarhizium anisopliae sensu lato: study on f1 generation. | the entomopathogenic fungus, metarhizium anisopliae (metsch.) sorokin is a valuable biocontrol agent attacking larval stages of many lepidopteran pests including helicoverpa armigera (hübner). sub-lethal effects of m. anisopliae sensu lato (s.l.) (isolate m14) were investigated on life table parameters of offspring from treated larvae of h. armigera. duration of different life stages was significantly affected by fungal treatments. fecundity was decreased in females derived from h. armigera larv ... | 2016 | 27247225 |
| expression of chitinase genes of metarhizium anisopliae isolates in lepidopteran pests and on synthetic media. | pathogenecity of the well characterized entomopathogenic fungus metarhizium anisopliae used for biocontrol of a wide range of insect pests secretes hydrolytic enzymes that degrade the host cuticle. the chitinolytic activity of high and low virulent isolates of m. anisopliae was assayed on minimal medium (mm) + colloidal chitin and mm supplemented with insect cuticles. ex- pression pattern of four chitinase genes (chitinase (chi), chi 1, chi 2, chi 3) was profiled during pathogenic stages of the ... | 2012 | 22581664 |
| yeast one-hybrid screening the potential regulator of cyp6b6 overexpression of helicoverpa armigera under 2-tridecanone stress. | in insect, the cytochrome p450 plays a pivotal role in detoxification to toxic allelochemicals. helicoverpa armigera can tolerate and survive in 2-tridecanone treatment owing to the cyp6b6 responsive expression, which is controlled by some regulatory dna sequences and transcription regulators. therefore, the 2-tridecanone responsive region and transcription regulators of the cyp6b6 are responsible for detoxification of cotton bollworm. in this study, we used yeast one-hybrid to screen two potent ... | 2016 | 26696496 |
| semi-selective fatty acyl reductases from four heliothine moths influence the specific pheromone composition. | sex pheromones are essential in moth mate communication. information on pheromone biosynthetic genes and enzymes is needed to comprehend the mechanisms that contribute to specificity of pheromone signals. most heliothine moths use sex pheromones with (z)-11-hexadecenal as the major component in combination with minor fatty aldehydes and alcohols. in this study we focus on four closely related species, heliothis virescens, heliothis subflexa, helicoverpa armigera and helicoverpa assulta, which us ... | 2012 | 22615947 |
| orf85 of hearnpv encodes the per os infectivity factor 4 (pif4) and is essential for the formation of the pif complex. | orf85 of helicoverpa armigera nucleopolyhedrovirus (hearnpv) encodes a homologue of the per os infectivity factor 4 (pif-4) of autographa californica multiple nucleocapsid nucleopolyhedrovirus (acmnpv). in this paper, the functions of ha85, particularly in relation to oral infection and interactions with other pifs were investigated. an ha85-disrupted recombinant hearnpv was generated and resulted in a complete loss of oral infectivity. western blotting and co-immunoprecipitation (co-ip) analyse ... | 2012 | 22386821 |
| improving the robustness of a low-cost insect cell medium for baculovirus biopesticides production, via hydrolysate streamlining using a tube bioreactor-based statistical optimization routine. | a critical component of an in vitro production process for baculovirus biopesticides is a growth medium that is efficacious, robust, and inexpensive. an in-house low-cost serum-free medium, vpm3, has been shown to be very promising in supporting helicoverpa armigera nucleopolyhedrovirus (hasnpv) production in h. zea insect cell suspension cultures, for use as a biopesticide against the heliothine pest complex. however, vpm3 is composed of a significant number of undefined components, including f ... | 2012 | 22323401 |
| identification of a toxic serralysin family protease with unique thermostable property from s. marcescens fs14. | a serralysin family protease (serralysin-like protease b, spb) with unique v-shaped thermostable property was isolated and identified from the serratia marcescens fs14 by biochemical and molecular biological methods. it is the first time to report the isolation of a native serralysin family protease directly from serratia species except the well-studied serralysin. spb has an optimum ph at 8.0 and an optimum temperature at 37°c. it shows high proteolytic activities after pretreated at 4-50°c for ... | 2016 | 27543346 |
| various bioactivity and relationship of structure-activity of matrine analogues. | for the first time, the botanic source natural product matrine was reported to have more potent inhibitory activity against tobacco mosaic virus (tmv) than the commercial virucide ribavirin. on the basis of the structural diversity modification strategy, a series of matrine derivatives was synthesized and systematically evaluated for their antiviral activity against tmv, fungicidal activity, and insecticidal activity. as a result, compounds 3 (inhibitory rate 67.3%, 69.5%, 63.7%, 63.0% at 500 μg ... | 2017 | 28248103 |
| biocontrol potential of steinernema thermophilum and its symbiont xenorhabdus indica against lepidopteran pests: virulence to egg and larval stages. | under laboratory conditions, the biocontrol potential of steinernema thermophilum was tested against eggs and larval stages of two important lepidopteran insect pests, helicoverpa armigera and spodoptera litura (polyphagous pests), as well as galleria mellonella (used as a model host). in terms of host susceptibility of lepidopteran larvae to s. thermophilum, based on the lc50 36 hr after treatment, g. mellonella (lc50 = 16.28 ij/larva) was found to be more susceptible than s. litura (lc50 = 85 ... | 2014 | 24643472 |
| extracellular novel metalloprotease from xenorhabdus indica and its potential as an insecticidal agent. | proteases produced by xenorhabdus are known to play a significant role in virulence leading to insect mortality. the present study was undertaken to purify and characterize protease from xenorhabdus indica, an endosymbiont of nematode steinernema thermophilum, and to decipher its role in insect mortality and its efficacy to control helicoverpa armigera. a set of 10 strains of xenorhabdus isolated from different regions of india were screened for protease activity on the basis of zone of clearing ... | 2013 | 23928843 |
| a novel pilin subunit from xenorhabdus nematophila, an insect pathogen, confers pest resistance in tobacco and tomato. | overexpression of insecticidal pilin subunit from xenorhabdus nematophila protects transgenic tobacco and tomato plants against helicoverpa armigera. xenorhabdus nematophila is a pathogenic bacterium producing toxins that kill the larval host. previously, we characterized a pilin subunit of x. nematophila which was found to be a pore-forming toxin and cytotoxic to the larval hemocytes of helicoverpa armigera by causing agglutination and lysis of the cells. in the present study, we report the eff ... | 2015 | 26164296 |
| ectopic expression of groel from xenorhabdus nematophila in tomato enhances resistance against helicoverpa armigera and salt and thermal stress. | the groel homolog xngroel protein of xenorhabdus nematophila belongs to a highly conserved family of molecular chaperones/heat shock proteins (hsps). xngroel was shown to possess oral insecticidal activity against a major crop pest helicoverpa armigera. under normal conditions, the hsps/chaperones facilitate folding, assembly, and translocation of cellular proteins, while in stress conditions they protect proteins from denaturation. in this study, we describe generation of transgenic tomato plan ... | 2015 | 25958082 |
| a novel insecticidal groel protein from xenorhabdus nematophila confers insect resistance in tobacco. | xenorhabdus nematophila is an entomopathogenic bacteria. it secretes a groel homolog, xngroel protein, toxic to its larval prey. groel belongs to the family of molecular chaperones and is required for proper folding of cellular proteins. oral ingestion of insecticidal xngroel protein is toxic to helicoverpa armigera, leading to cessation of growth and development of the larvae. in the present study, the insecticidal efficacy of xngroel against h. armigera has been evaluated in transgenic tobacco ... | 2014 | 23888329 |
| landscape changes in a lowland in benin: ecological impact on pests and natural enemies. | habitat management involving conservative biological control could be a good crop pest management option in poor african countries. a survey was conducted from august 2013 to july 2014 in a rainfed lowland region near pélébina, northern benin, in order to characterize spatiotemporal landscape changes and investigate their influence on the main crop pests and their associated natural enemies. the area was mapped mainly regarding crop fields and fallows. visual observations were recorded and a dat ... | 2015 | 27145573 |
| field evaluation of a botanical formulation from the milky mangrove excoecaria agallocha l. against helicoverpa armigera hübner. in abelmoschus esculentus (lady's finger) and cajanus cajan (pigeon pea). | to evaluate a formulation from the milky mangrove tree excoecaria agallocha l. (e. agallocha) against helicoverpa armigera hubner (h. armigera). | 2014 | 25312115 |
| chemically mediated prey-approaching behaviour of the reduviid predator rhynocoris fuscipes (fabricius) (insecta: heteroptera: reduviidae) by y-arm olfactometer. | the reduviid predator, rhynocoris fuscipes (fabricius) (heteroptera: reduviidae) is a potential predator inhibiting diverse agroecosystems and preying upon about 50 minor as well as major insect pests. the prey approaching behaviour of r. fuscipes (fabricius) to the hexane extracts of insect pests viz., helicoverpa armigera hubner, spodoptera litura (fabricius), achaea janata linnaeus, dysdercus cingulatus fabricius and mylabris indica thunberg was assessed in y-shaped olfactometer in terms of e ... | 2013 | 24511748 |
| functional validation of the carbon dioxide receptor in labial palps of helicoverpa armigera moths. | adult moths possess an organ in their labial palps, the labial-palp pit organ, which is specialized for sensing carbon dioxide (co2). they use co2 as a cue to detect healthy plants and find food or lay eggs on them. the molecular bases of the co2 receptor in drosophila melanogaster and aedes aegypti have been reported, but the molecular mechanisms of the co2 receptor in lepidoptera remains elusive. in this study, we first re-examined three putative helicoverpa armigera co2 gustatory receptor gen ... | 2016 | 27060445 |
| emamectin, a novel insecticide for controlling field crop pests. | emamectin is a macrocyclic lactone insecticide with low toxicity to non-target organisms and the environment, and is considered an important component in pest-management programmes for controlling field crop pests. it is a powerful compound for controlling the cotton bollworm helicoverpa armigera (hübner). a spray concentration of 25 mg ai litre-1 in a cotton field resulted in over 90% suppression of h armigera larvae up to day 28 after treatment, while similar mortality of the egyptian cotton l ... | 2002 | 12449526 |
| expression of cry1ac in transgenic bt soybean lines and their efficiency in controlling lepidopteran pests. | two transgenic lines of the soybean glycine max, mon87701 expressing the cry1ac protein and mon87701rr2y expressing cry1ac + epsps proteins, were evaluated for their resistance to four lepidopteran pests in the laboratory using detached-leaf bioassays throughout the soybean growth seasons (before anthesis, during anthesis and after anthesis) in china. enzyme-linked immunosorbent assays (elisas) were used to monitor the cry1ac expression in soybean leaves. | 2013 | 23564718 |
| molecular characterization of diapause hormone and pheromone biosynthesis activating neuropeptide from the black-back prominent moth, clostera anastomosis (l.) (lepidoptera, notodontidae). | using a strategy of rapid amplification of cdna ends, the cdna of diapause hormone (dh) and pheromone biosynthesis activating neuropeptide (pban) was cloned from the head of clostera anastomosis (l.). the cloan-dh-pban cdna contains an open reading frame encoding a 196-amino acid preprohormone, from which five putative fxprl peptides, dh, pban, alpha-sgnp(sgnp, suboesophageal ganglion neuropeptide), beta-sgnp and gamma-sgnp, are released. comparing the deduced amino acid sequences from cdnas of ... | 2007 | 17967345 |
| [expression and synergistic function of enhancin-like gene of agrotis segetum granulovirus]. | enhancin is an enhancing protein chiefly found in insect baculoviruses. one enhancin homologue was identified, by blast method, in agrotis segetum granulovirus (agsegv) genome, named enhancin-like. sequence analysis indicated that this gene includes the conserved domains, conserved in other enhancin, and it has no signal peptide or a-transmembrane helix. a proline-rich domain, which is similar to those of mammals, is present at its c-terminal. to analyze the synergistic function of agsegv enhanc ... | 2012 | 22764529 |
| entomopoxvirus of cotton bollworm, helicoverpa armigera (hbn.). | occurrence of an entomopoxvirus (epv) from a lepidopteran insect viz;. cotton bollworm, h. armigera (haepv) along with gross pathological symptoms is reported for the first time in india. histopathological study revealed that the fat body being the most favoured site of infection followed by haemocytes and gut epithelium. haepv was found to be not cross infective to six of the agricultural lepidopteran insect pests except for the potato black cutworm, agrotis segetum registering 100% mortality s ... | 2002 | 12597557 |
| identification of a kunitz inhibitor from albizzia kalkora and its inhibitory effect against pest midgut proteases. | a purification protocol, involving water extraction, ammonium sulfate precipitation, sepharose 4b-trypsin affinity and fplc superdex g-75 chromatography, was employed to isolate a trypsin inhibitor from albizzia kalkora seeds. the inhibitor, which had a molecular mass of 19,768.23 da, consisted of two disulfide-linked polypeptide chains with approximate molecular mass of 15.5 and 4.5 kda, respectively. it was stable from ph 2-12 for 24 h, whereas it was unstable either above 80 degrees c for 10 ... | 2008 | 18368297 |
| molecular characterization of nucleopolyhedrovirus of three lepidopteran pests using late expression factor-8 gene. | a pcr based method for detection of viral dna in nucleopolyhedrovirus of three lepidopterans, spodoptera litura, amsacta albistriga and helicoverpa armigera, was developed by employing the late expression factor-8 (lef-8) gene of three npv using specific primers. the amplicons of 689, 699 and 665 bp were amplified, respectively, and the nucleotide sequences were submitted to genbank and the accession numbers were obtained. the sequences of lef-8 gene of s. litura npv and h. armigera npv matched ... | 2013 | 24426259 |
| complete nucleotide sequence of the fusolin gene of an entomopoxvirus in the cupreous chafer, anomala cuprea hope (coleoptera: scarabaeidae). | the fusolin gene of anomala cuprea entomopoxvirus (acepv) was cloned and sequenced. the sequence was compared with that of fusolin genes of epvs from other insects such as melolontha melolontha (mmepv), choristoneura biennis (cbepv) and heliothis armigera (haepv) previously reported. the gene harbored a single open reading frame (orf) of 1119 nt capable of coding for a protein of 43.3 kda. the microsequencing of the protein showed the cleavage of a signal peptide of 16 amino acid (aa) residues. ... | 1997 | 9474783 |
| screening for antifeedant and larvicidal activity of plant extracts against helicoverpa armigera (hübner), sylepta derogata (f.) and anopheles stephensi (liston). | plant extracts, especially botanical insecticides, are currently studied more and more because of the possibility of their use in plant protection. biological activity of five solvent plant extracts were studied using fourth instar larvae of gram pod borer helicoverpa armigera (lepidoptera: noctuidae), cotton leaf roller sylepta derogata (lepidoptera: pyralidae) and malaria vector anopheles stephensi (diptera: culicidae). antifeedant and larvicidal activity of acetone, chloroform, ethyl acetate, ... | 2008 | 18679716 |
| do pollinator distributions underlie the evolution of pollination ecotypes in the cape shrub erica plukenetii? | according to the grant-stebbins model of pollinator-driven divergence, plants that disperse beyond the range of their specialized pollinator may adapt to a new pollination system. although this model provides a compelling explanation for pollination ecotype formation, few studies have directly tested its validity in nature. here we investigate the distribution and pollination biology of several subspecies of the shrub erica plukenetii from the cape floristic region in south africa. we analyse th ... | 2014 | 24071499 |
| cell culture for production of insecticidal viruses. | while large-scale culture of insect cells will need to be conducted using bioreactors up to 10,000 l scale, many of the main challenges for cell culture-based production of insecticidal viruses can be studied using small-scale (20-500 ml) shaker/spinner flasks, either in free suspension or using microcarrier-based systems. these challenges still relate to the development of appropriate cell lines, stability of virus strains in culture, enhancing virus yields per cell, and the development of seru ... | 2016 | 27565495 |
| differential induction of flavonoids in groundnut in response to helicoverpa armigera and aphis craccivora infestation. | flavonoids are important plant secondary metabolites, which protect plants from various stresses, including herbivory. plants differentially respond to insects with different modes of action. high performance liquid chromatography (hplc) fingerprinting of phenols of groundnut (arachis hypogaea) plants with differential levels of resistance was carried out in response to helicoverpa armigera (chewing insect) and aphis craccivora (sucking pest) infestation. the genotypes used were icgv 86699, icgv ... | 2016 | 27398031 |
| additive effects on the improvement of insecticidal activity: design, synthesis, and insecticidal activity of novel pymetrozine derivatives. | a series of new pymetrozine analogues containing both methyl on the imine carbon and phenoxy group at the pyridine ring were designed and synthesized. their insecticidal activities against bean aphid (aphis craccivora), mosquito larvae (culex pipiens pallens), cotton bollworm (helicoverpa armigera), corn borer (ostrinia nubilalis) and oriental armyworm (mythimna separata) were evaluated. the results of bioassays indicated that most of the target compounds showed good insecticidal activity agains ... | 2016 | 26342545 |
| design, synthesis, and insecticidal evaluation of new pyrazole derivatives containing imine, oxime ether, oxime ester, and dihydroisoxazoline groups based on the inhibitor binding pocket of respiratory complex i. | on the basis of complex i receptor protein binding site and commercial tebufenpyrad and tolfenpyrad, four series of novel pyrazole-5-carboxamides containing imine, oxime ether, oxime ester, and dihydroisoxazoline were designed and synthesized via the key intermediate 4-chloro-3-ethyl-n-(4-formylbenzyl)-1-methyl-1h-pyrazole-5-carboxamide. the structures of target compounds were confirmed by ¹h nmr and high-resolution mass spectrum (hrms). the results of bioassays indicated that the target compoun ... | 2013 | 23972278 |
| design, synthesis, and insecticidal activity of novel pyrazole derivatives containing α-hydroxymethyl-n-benzyl carboxamide, α-chloromethyl-n-benzyl carboxamide, and 4,5-dihydrooxazole moieties. | on the basis of commercial insecticides tebufenpyrad and tolfenpyrad, two series of novel pyrazole-5-carboxamides containing α-hydroxymethyl-n-benzyl or α-chloromethyl-n-benzyl and pyrazoles containing 4,5-dihydrooxazole moieties were designed and synthesized via the key intermediate 2-amino-1-(4-substituted) phenyl ethanol. the structures of target compounds were confirmed by (1)h nmr and elemental analysis or high-resolution mass spectrum (hrms), and their activities against cotton bollworm (h ... | 2012 | 22304385 |
| first results of the application of a new neemazal powder formulation in hydroponics against different pest insects. | neemazal pc (0.5% azadirachtin) is a new standardised powder formulation from the seed kernels of the tropical neem tree (azadirachta indica a. juss) with an inert carrier. first experiments with beans--as a model-system for hydroponics--show that active ingredient is taken up by the plants through the roots and is transported efficiently with the plant sap to the leaves. after application of neemazal pc solution (0.01-1%) to the roots sucking (aphis fabae hom., aphididae) and free feeding (heli ... | 2002 | 12696431 |
| mass rearing and augmentative biological control evaluation of rhynocoris fuscipes (hemiptera: reduviidae) against multiple pests of cotton. | rhynocoris fuscipes (fab.) (hemiptera: reduviidae) is a generalist predator of cotton pests and is commonly found inhabiting cotton-growing regions in southern india. with the goal of integrating this predator in standard management practices used against cotton pests on a commercial scale, (1) we developed a protocol for adult group rearing of this predator inside micro-environmental cages (mecs), and (2) we evaluated the biocontrol potential of mass-produced predators against cotton pests unde ... | 2017 | 28127861 |
| effects of single and dual species herbivory on the behavioural responses of three thrips species to cotton seedlings. | this study investigated the olfactory responses of three thrips species [frankliniella schultzei trybom, f. occidentalis pergrande and thrips tabaci lindeman (thysanoptera: thripidae)] to cotton seedlings [gossypium hirsutum l. (malvales: malvaceae)] simultaneously damaged by different combinations of herbivores. cotton seedlings were damaged by foliar feeding tetranychus urticae koch (trombidiforms: tetranychidae), helicoverpa armigera hübner (lepidoptera: noctuidae), aphis gossypii glover (hem ... | 2016 | 27029603 |
| impacts of transgenic poplar-cotton agro-ecosystems upon target pests and non-target insects under field conditions. | poplar-cotton agro-ecosystems are the main agricultural planting modes of cotton fields in china. with increasing acres devoted to transgenic insect-resistant poplar and transgenic insect-resistant cotton, studies examining the effects of transgenic plants on target and non-target insects become increasingly important. we systematically surveyed populations of both target pests and non-target insects for 4 different combinations of poplar-cotton eco-systems over 3 years. transgenic bt cotton str ... | 2015 | 26345739 |
| development of transgenic cryia(c) + gna cotton plants via pollen tube pathway method confers resistance to helicoverpa armigera and aphis gossypii glover. | elite cotton cultivar sumian16 was transformed with p7rpsbk-mgna-nptii containing bt (cryia(c)), galanthus nivalis agglutinin (gna) resistance genes and selectable marker nptii gene via the pollen tube pathway method and two fertile transgenic bt + gna plants were obtained in the present study. the integration and expression of the bt and gna genes were confirmed by molecular biology techniques and insect bioassays. insect bioassays showed that the transformed plants were highly toxic to bollwor ... | 2013 | 23143495 |
| temporal synergism by microencapsulation of piperonyl butoxide and alpha-cypermethrin overcomes insecticide resistance in crop pests. | a microencapsulated formulation that gives a burst release of piperonyl butoxide (pbo) several hours before a burst release of a conventional pyrethroid can effectively overcome metabolic resistance in bemisia tabaci gennadius, helicoverpa armigera (hübner), aphis gossypii glover and myzus persicae sulzer. this increase in efficacy against resistant pests was reflected in a field trial against b. tabaci on cotton, eliminating the need for two treatments. the ratio between the active insecticide ... | 2007 | 17304634 |
| bt cry1ie toxin does not impact the survival and pollen consumption of chinese honey bees, apis cerana cerana (hymenoptera, apidae). | the cry1ie gene may be a good candidate for the development of bt maize because over-expression of cry1ie is highly toxic to lepidopteran pests such as heliothis armigera hübner and ostrinia furnacalis guenée. the bt cry1ie gene also has no cross resistance with other insecticidal proteins such as cry1ab, cry1ac, cry1ah, or cry1f. chinese honey bees (apis cerana cerana) are potentially exposed to insect-resistant genetically modified (irgm) crops expressing cry1ie toxin via the collection of irg ... | 2016 | 27670271 |
| pheromone lure and trap color affects bycatch in agricultural landscapes of utah. | aerial traps, using combinations of color and attractive lures, are a critical tool for detecting and managing insect pest populations. yet, despite improvements in trap efficacy, collection of nontarget species ("bycatch") plagues many insect pest surveys. bycatch can influence survey effectiveness by reducing the available space for target species and increasing trap screening time, especially in areas where thousands of insects are captured as bycatch in a given season. additionally, bycatch ... | 2016 | 27412193 |
| pollen-mediated gene flow from transgenic cotton under greenhouse conditions is dependent on different pollinators. | with the large-scale release of genetically modified (gm) crops, there are ecological concerns on transgene movement from gm crops to non-gm counterparts and wild relatives. in this research, we conducted greenhouse experiments to measure pollen-mediated gene flow (pgf) in the absence and presence of pollinators (bombus ignitus, apis mellifera and pieris rapae) in one gm cotton (resistant to the insect helicoverpa armigera and the herbicide glyphosate) and two non-gm lines (shiyuan321 and hai712 ... | 2015 | 26525573 |
| overexpression of poplar wounding-inducible genes in arabidopsis caused improved resistance against helicoverpa armigera (hübner) larvae. | four highly inducible genes of poplar trees, ptdkti5, ptdwin4, ptdpop3 from hybrid poplar (populus trichocarpa × p. deltoides) and ptkti2 from trembling aspen (populus tremuloides michx.) have been individually transformed into arabidopsis thaliana for overexpression. high transcriptional level of each transgene in transgenic arabidopsis lines was confirmed by rt-pcr analysis. the development, body weight and survivorship of cotton bollworm (helicoverpa armigera) fed on four types of transgenic ... | 2012 | 23226090 |
| interaction of glucosinolate content of arabidopsis thaliana mutant lines and feeding and oviposition by generalist and specialist lepidopterans. | the diamondback moth, plutella xylostella l. (lepidoptera: plutellidae), is an insect specialized on glucosinolate-containing brassicaceae that uses glucosinolates in host-plant recognition. we used wild-type and mutants of arabidopsis thaliana (l.) heynh. (brassicaceae) to investigate the interaction between plant glucosinolate and myrosinase content and herbivory by larvae of the generalist helicoverpa armigera hübner (lepidoptera: noctuidae) and the specialist p. xylostella. we also measured ... | 2013 | 23218016 |
| metabolism of glucosinolate-derived isothiocyanates to glutathione conjugates in generalist lepidopteran herbivores. | the defensive properties of the glucosinolate-myrosinase system in plants of the order brassicales have been attributed to the formation of toxic isothiocyanates generated upon tissue damage. lepidopteran herbivores specialised on brassicaceous plants have been shown to possess biochemical mechanisms preventing the formation of isothiocyanates. yet, no such mechanisms are known for generalist lepidopterans which also occasionally but successfully feed on plants of the brassicales. after feeding ... | 2012 | 22193392 |
| nonuniform distribution of glucosinolates in arabidopsis thaliana leaves has important consequences for plant defense. | the spatial distribution of plant defenses within a leaf may be critical in explaining patterns of herbivory. the generalist lepidopteran larvae, helicoverpa armigera (the cotton bollworm), avoided the midvein and periphery of arabidopsis thaliana rosette leaves and fed almost exclusively on the inner lamina. this feeding pattern was attributed to glucosinolates because it was not evident in a myrosinase mutant that lacks the ability to activate glucosinolate defenses by hydrolysis. to measure t ... | 2008 | 18408160 |
| comparative host selection responses of specialist (helicoverpa assulta) and generalist (helicoverpa armigera) moths in complex plant environments. | we tested the behavioral responses of ovipositing females and natal larvae of two sibling species, a generalist helicoverpa armigera (hübner) and a specialist helicoverpa assulta (guenée), to odor sources emitted from different combinations of six plant species (tobacco, nicotiana tabacum; hot pepper, capsicum annuum; tomato, solanum esculentum; cotton, gossypium hirsutum; peanut, arachis hypogaea; maize, zea mays). under the conditions of plant materials versus corresponding controls, both stag ... | 2017 | 28182679 |
| induced resistance to helicoverpa armigera through exogenous application of jasmonic acid and salicylic acid in groundnut, arachis hypogaea. | induced resistance to helicoverpa armigera through exogenous application of jasmonic acid (ja) and salicylic acid (sa) was studied in groundnut genotypes (icgv 86699, icgv 86031, icg 2271 and icg 1697) with different levels of resistance to insects and the susceptible check jl 24 under greenhouse conditions. activities of oxidative enzymes and the amounts of secondary metabolites and proteins were quantified at 6 days after ja and sa application/insect infestation. data were also recorded on pla ... | 2015 | 25488591 |
| determining the major bt refuge crops for cotton bollworm in north china. | evaluation of the effectiveness of refuge strategies involved in cotton bollworm bt resistance management would be aided by technologies that allow monitoring and quantification of key factors that affect the process under field conditions. we hypothesized that characterization of stable carbon and nitrogen isotopes in adult bollworm, helicoverpa armigera (hübner) (lepidoptera: noctuidae) moths may aid in determining the larval host that they developed upon. we found moths reared from larvae fed ... | 2015 | 25196072 |
| detached leaf assay to screen for host plant resistance to helicoverpa armigera. | the noctuid helicoverpa armigera (hübner) is a major insect pest of chickpea cicer arietinum l., pigeonpea cajanus cajan (l.) millsp., peanut arachis hypogaea l., and cotton gossypium spp., and host plant resistance is an important component for managing this pest in different crops. because of variations in insect density and staggered flowering of the test material, it is difficult to identify cultivars with stable resistance to h. armigera across seasons and locations. to overcome these probl ... | 2005 | 15889750 |
| gene expression patterns of helicoverpa armigera gut proteases. | relative quantification of reported gut proteinase cdnas from helicoverpa armigera larvae fed on various host plants (cotton, chickpea, pigeonpea, tomato and okra), non-host plant pis (winged bean, bitter gourd, ground nut, and capsicum) and during larval development has been carried out using semi-quantitative rt-pcr. five trypsin-like and three chymotrypsin-like proteinases were categorized as insensitive or sensitive to most of the proteinase inhibitors (pis) and insensitive/sensitive to spec ... | 2005 | 15763471 |
| successive use of non-host plant proteinase inhibitors required for effective inhibition of helicoverpa armigera gut proteinases and larval growth | we report on the efficacy of proteinase inhibitors (pis) from three host plants (chickpea [cicer arietinum], pigeonpea [cajanus cajan], and cotton [gossypium arboreum]) and three non-host (groundnut [arachis hypogea], winged bean [psophocarpus tetragonolobus], and potato [solanum tuberosum]) in retarding the growth of helicoverpa armigera larvae, a devastating pest of important crop plants. enzyme assays and electrophoretic analysis of interaction of h. armigera gut proteinases (hgps) with pis r ... | 1999 | 10517841 |