Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| a deletion mutant ndv200 of the bacillus thuringiensis vip3br insecticidal toxin gene is a prospective candidate for the next generation of genetically modified crop plants resistant to lepidopteran insect damage. | ectopic expression of a deletion mutant ( ndv200 ) of bacillus thuringiensis vip3br gene in tobacco plant provided almost complete protection against major crop pests cotton boll worm ( helicoverpa armigera ), black cut worm ( agrotis ipsilon ) and cotton leaf worm ( spodoptera littoralis ). whereas vip3br transgenic tobacco plant failed to protect themselves from these insects and showed resistance towards cotton leaf worm only. an analogous form of the bacillus thuringiensis vip3aa insecticida ... | 2015 | 25912191 |
| bio-physical evaluation and in vivo delivery of plant proteinase inhibitor immobilized on silica nanospheres. | recombinant expression of capsicum annuum proteinase inhibitors (canpi-13) and its application via synthetic carrier for the crop protection is the prime objective of our study. herein, we explored proteinase inhibitor peptide immobilization on silica based nanospheres and rods followed by its ph mediated release in vitro and in vivo. initial studies suggested silica nanospheres to be a suitable candidate for peptide immobilization. furthermore, the interactions were characterized biophysically ... | 2015 | 25909183 |
| 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 |
| a toxin-binding alkaline phosphatase fragment synergizes bt toxin cry1ac against susceptible and resistant helicoverpa armigera. | evolution of resistance by insects threatens the continued success of pest control using insecticidal crystal (cry) proteins from the bacterium bacillus thuringiensis (bt) in sprays and transgenic plants. in this study, laboratory selection with cry1ac yielded five strains of cotton bollworm, helicoverpa armigera, with resistance ratios at the median lethal concentration (lc50) of activated cry1ac ranging from 22 to 1700. reduced activity and reduced transcription of an alkaline phosphatase prot ... | 2015 | 25885820 |
| transcriptome comparison of the sex pheromone glands from two sibling helicoverpa species with opposite sex pheromone components. | differences in sex pheromone component can lead to reproductive isolation. the sibling noctuid species, helicoverpa armigera and helicoverpa assulta, share the same two sex pheromone components, z9-16:ald and z11-16:ald, but in opposite ratios, providing an typical example of such reproductive isolation. to investigate how the ratios of the pheromone components are differently regulated in the two species, we sequenced cdna libraries from the pheromone glands of h. armigera and h. assulta. after ... | 2015 | 25792497 |
| carbon dioxide receptor genes in cotton bollworm helicoverpa armigera. | carbon dioxide (co2) is important in insect ecology, eliciting a range of behaviours across different species. interestingly, the numbers of co2 gustatory receptors (grs) vary among insect species. in the model organism drosophila melanogaster, two grs (dmelgr21a and dmelgr63a) have been shown to detect co2. in the butterfly, moth, beetle and mosquito species studied so far, three co2 gr genes have been identified, while in tsetse flies, four co2 gr genes have been identified. in other species i ... | 2015 | 25724420 |
| enhancement of bacillus thuringiensis insecticidal activity by combining cry1ac and bi-functional toxin hwtx-xi from spider. | in order to assess the potency of bi-functional hwtx-xi toxin from spider ornithoctonus huwena in improving the insecticidal activity of bacillus thuringiensis, a fusion gene of cry1ac and hwtx-xi was constructed and expressed in an acrystalliferous b. thuringiensis strain cry(-)b. western blot analysis and microscopic observation revealed that the recombinant strain could express 140-kda cry1ac-hwtx-xi fusion protein and produce parasporal inclusions during sporulation. bioassay using the larva ... | 2016 | 25721170 |
| molecular docking and site-directed mutagenesis of a bacillus thuringiensis chitinase to improve chitinolytic, synergistic lepidopteran-larvicidal and nematicidal activities. | bacterial chitinases are useful in the biocontrol of agriculturally important pests and fungal pathogens. however, the utility of naturally occurring bacterial chitinases is often limited by their low enzyme activity. in this study, we constructed mutants of a bacillus thuringiensis chitinase with enhanced activity based on homology modeling, molecular docking, and the site-directed mutagenesis of target residues to modify spatial positions, steric hindrances, or hydrophilicity/hydrophobicity. w ... | 2015 | 25678849 |
| establishment and characterization of a novel cell line from midgut tissue of helicoverpa armigera (lepidoptera: noctuidae). | the midgut of lepidopteran larvae serves as a target for many pathogens such as bacillus thuringiensis (bt). cell lines originating from midgut tissues will be very helpful tools in many research fields. however, to date, no bt-susceptible midgut-derived cell lines are available. here, we reported that a novel cell line, designated as hnu-ha-mg1, was established from midgut tissue of the fourth instar larvae of helicoverpa armigera. this cell line grew well in grace's insect cell culture medium ... | 2015 | 25678461 |
| the steroid hormone 20-hydroxyecdysone via nongenomic pathway activates ca2+/calmodulin-dependent protein kinase ii to regulate gene expression. | the steroid hormone 20-hydroxyecdysone (20e) triggers calcium signaling pathway to regulate 20e response gene expression, but the mechanism underlying this process remains unclear. we propose that the 20e-induced phosphorylation of ca(2+)/calmodulin-dependent protein kinase ii (camkii) serves an important function in 20e response gene transcription in the lepidopteran insect helicoverpa armigera. camkii showed increased expression and phosphorylation during metamorphosis. 20e elevated camkii pho ... | 2015 | 25670853 |
| endogenous expression of a bt toxin receptor in the cry1ac-susceptible insect cell line and its synergistic effect with cadherin on cytotoxicity of activated cry1ac. | although many insect cell lines derived from various tissues are available, it is unclear whether endogenous receptors of bacillus thuringiensis (bt) crystal toxins are expressed in these cell lines. in the present study, we demonstrated that the ovaries-derived spodoptera litura sl-hp cell line was susceptible to activated cry1ac although larvae of s. litura are not susceptible to the toxin. assays of the transcriptome revealed that thirteen atp-binding cassette transporter genes (abc) were exp ... | 2015 | 25662100 |
| 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 |
| transgenic plants expressing the aait/gna fusion protein show increased resistance and toxicity to both chewing and sucking pests. | the adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. to achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, arabidopsis, and rice plants expressing the fusion protein, aait/gna, in which an insecticidal scorpion venom neurotoxin (androctonus australis toxin, aait) is fused to snowdrop lectin (galanthus nivalis agglutinin, gna). compared with transgenic tobac ... | 2016 | 25641865 |
| cross-resistance and interactions between bt toxins cry1ac and cry2ab against the cotton bollworm. | to delay evolution of pest resistance to transgenic crops producing insecticidal proteins from bacillus thuringiensis (bt), the "pyramid" strategy uses plants that produce two or more toxins that kill the same pest. we conducted laboratory diet experiments with the cotton bollworm, helicoverpa armigera, to evaluate cross-resistance and interactions between two toxins in pyramided bt cotton (cry1ac and cry2ab). selection with cry1ac for 125 generations produced 1000-fold resistance to cry1ac and ... | 2015 | 25586723 |
| the influence of a 21 kda kunitz-type trypsin inhibitor from nonhost madras thorn, pithecellobium dulce, seeds on h. armigera (hübner) (lepidoptera: noctuidae). | a trypsin inhibitor purified from the seeds of the manila tamarind, pithecellobium dulce (pdti), was studied for its effects on growth parameters and developmental stages of helicoverpa armigera. pdti exhibited inhibitory activity against bovine trypsin (∼86%; ∼1.33 ug/ml ic50). the inhibitory activity of pdti was unaltered over a wide range of temperature, ph, and in the presence of dithiothreitol. larval midgut proteases were unable to digest pdti for up to 12 h of incubation. dixon and linewe ... | 2015 | 25580830 |
| 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 |
| 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 |
| large-scale test of the natural refuge strategy for delaying insect resistance to transgenic bt crops. | the 'natural refuge strategy" for delaying insect resistance to transgenic cotton that produces insecticidal proteins from bacillus thuringiensis (bt) relies on refuges of host plants other than cotton that do not make bt toxins. we tested this widely adopted strategy by comparing predictions from modeling with data from a four-year field study of cotton bollworm (helicoverpa armigera) resistance to transgenic cotton producing bt toxin cry1ac in six provinces of northern china. bioassay data rev ... | 2015 | 25503384 |
| 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 |
| 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 |
| bio-potency of a 21 kda kunitz-type trypsin inhibitor from tamarindus indica seeds on the developmental physiology of h. armigera. | a trypsin inhibitor purified from the seeds of tamarindus indica by sephadex g-75, deae-sepharose and trypsin-sepharose cl-4b columns was studied for its antifeedant, larvicidal, pupicidal and growth inhibitory activities against helicoverpa armigera larvae. tamarindus trypsin inhibitor (tti) exhibited inhibitory activity towards total gut proteolytic enzymes of h. armigera (~87%) and bovine trypsin (~84%). lethal doses which caused mortality and weight reduction by 50% were 1% w/w and 0.50% w/w ... | 2014 | 25454525 |
| a transferrin gene associated with development and 2-tridecanone tolerance in helicoverpa armigera. | the full-length cdna (2320 bp) encoding a putative iron-binding transferrin protein from helicoverpa armigera was cloned and named hatrf. the putative hatrf sequence included 670 amino acids with a molecular mass of approximately 76 kda. quantitative pcr results demonstrated that the transcriptional level of hatrf was significantly higher in the sixth instar and pupa stages as compared with other developmental stages. hatrf transcripts were more abundant in fat bodies and in the epidermis than i ... | 2014 | 25430818 |
| cis-mediated down-regulation of a trypsin gene associated with bt resistance in cotton bollworm. | transgenic plants producing insecticidal proteins from the bacterium bacillus thuringiensis (bt) are useful for pest control, but their efficacy is reduced when pests evolve resistance. here we examined the mechanism of resistance to bt toxin cry1ac in the laboratory-selected lf5 strain of the cotton bollworm, helicoverpa armigera. this strain had 110-fold resistance to cry1ac protoxin and 39-fold resistance to cry1ac activated toxin. evaluation of five trypsin genes revealed 99% reduced transcr ... | 2014 | 25427690 |
| ghdrin1, a novel drought-induced gene of upland cotton (gossypium hirsutum l.) confers abiotic and biotic stress tolerance in transgenic tobacco. | a novel stress tolerance cdna fragment encoding ghdrin1 protein was identified and its regulation was studied in cotton boll tissues and seedlings subjected to various biotic and abiotic stresses. phylogenetic and conserved domain prediction indicated that ghdrin1 was annotated with a hypothetical protein of unknown function. subcellular localization showed that ghdrin1 is localized in the chloroplasts. the promoter sequence was isolated and subjected to in silico study. various cis-acting eleme ... | 2015 | 25413882 |
| expression of recombinant and mosaic cry1ac receptors from helicoverpa armigera and their influences on the cytotoxicity of activated cry1ac to spodoptera litura sl-hp cells. | bacillus thuringiensis (bt) toxin receptors play important roles in the killing of pests, and investigation on characterization of the receptors is essential for utilization of bt and management of insect resistance. here, recombinant and mosaic receptors of bt cry1ac toxin from helicoverpa armigera were expressed in spodoptera litura sl-hp cells and their influences on cytotoxicity of activated cry1ac toxin were investigated. when h. armigera aminopeptidase n1 (apn1), alkaline phosphatase 2 (al ... | 2016 | 25412589 |
| molecular and insecticidal characterization of a novel cry-related protein from bacillus thuringiensis toxic against myzus persicae. | this study describes the insecticidal activity of a novel bacillus thuringiensis cry-related protein with a deduced 799 amino acid sequence (~89 kda) and ~19% pairwise identity to the 95-kda-aphidicidal protein (sequence number 204) from patent us 8318900 and ~40% pairwise identity to the cancer cell killing cry proteins (parasporins cry41ab1 and cry41aa1), respectively. this novel cry-related protein contained the five conserved amino acid blocks and the three conserved domains commonly found i ... | 2014 | 25384108 |
| life table and consumption capacity of corn earworm, helicoverpa armigera, fed asparagus, asparagus officinalis. | the life table and consumption rate of helicoverpa armigera (hübner) (lepidoptera: noctuidae) reared on asparagus, asparagus officinalis l. (asparagales: asparagaceae) were studied under laboratory conditions to assess their interaction. development, survival, fecundity, and consumption data were analyzed by the age-stage, twosex life table. this study indicated that asparagus is a natural host of h. armigera. however, the poor nutritional content in asparagus foliage and the poor fitness of h. ... | 2014 | 25373181 |
| acute, sublethal, and combination effects of azadirachtin and bacillus thuringiensis on the cotton bollworm, helicoverpa armigera. | the cotton bollworm, helicoverpa armigera hübner (lepidoptera: noctuidae) is a polyphagous and cosmopolitan insect pest that causes damage to various plants. in this study, the lethal and sublethal effects of azadirachtin and bacillus thuringiensis berliner sub sp . kurstaki (bacillales: bacillaceae) were evaluated on third instar h. armigera under laboratory conditions. the lc50 values of azadirachtin and bt were 12.95 and 96.8 µg a.i./ml, respectively. a total mortality of 56.7% was caused on ... | 2014 | 25373177 |
| in-vitro antimicrobial, antibiofilm, cytotoxic, antifeedant and larvicidal properties of novel quinone isolated from aegle marmelos (linn.) correa. | plant metabolites have wide applications and have the potential to cure different diseases caused by microorganisms. the aim of the study was to evaluate the antimicrobial, antibiofilm, cytotoxic, antifeedant and larvicidal properties of novel quinine isolated from aegle marmelos (linn.) correa. | 2014 | 25359605 |
| densovirus is a mutualistic symbiont of a global crop pest (helicoverpa armigera) and protects against a baculovirus and bt biopesticide. | mutualistic associations between symbiotic bacteria and their hosts are common within insect systems. however, viruses are often considered as pathogens even though some have been reported to be beneficial to their hosts. herein, we report a novel densovirus, helicoverpa armigera densovirus-1 (hadnv-1) that appears to be beneficial to its host. hadnv-1 was found to be widespread in wild populations of h. armigera adults (>67% prevalence between 2008 and 2012). in wild larval populations, there w ... | 2014 | 25357125 |
| 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 |
| nitrate reductase and nitrite as additional components of defense system in pigeonpea (cajanus cajan l.) against helicoverpa armigera herbivory. | amylase inhibitors serve as attractive candidates of defense mechanisms against insect attack. therefore, the impediment of helicoverpa armigera digestion can be the effective way of controlling this pest population. nitrite was found to be a potent mixed non-competitive competitive inhibitor of partially purified α-amylase of h. armigera gut. this observation impelled us to determine the response of nitrite and nitrate reductase (nr) towards h. armigera infestation in nine pigeonpea genotypes ( ... | 2014 | 25307464 |
| identification and expression profiling of helicoverpa armigera micrornas and their possible role in the regulation of digestive protease genes. | the present investigation is an effort to determine the possible roles of micrornas (mirnas) in the regulation of protease gene expression in helicoverpa armigera upon exposure to plant protease inhibitors (pis). using illumina platform, deep sequencing of 12 small rna libraries was performed from h. armigera larvae fed on artificial diet (ad) or recombinant capsicum annuum pi-7 (rcanpi-7) incorporated diet, at various time intervals (0.5, 2, 6, 12, 24, and 48 h). sequencing data were analyzed w ... | 2014 | 25263090 |
| development of pod borer-resistant transgenic chickpea using a pod-specific and a constitutive promoter-driven fused cry1ab/ac gene. | we studied pod-specific msg promoter from soybean and developed different transgenic lines of chickpea expressing fused cry1ab/ac constitutively and pod specifically for resistance against the destructive pest helicoverpa armigera. crystal (cry) proteins derived from the soil bacterium bacillus thuringiensis (bt) play an important role in controlling infestation of helicoverpa armigera, which has been considered a serious problem in chickpea productivity. this study was undertaken to overcome th ... | 2014 | 25252910 |
| 20-hydroxyecdysone transcriptionally regulates humoral immunity in the fat body of helicoverpa armigera. | 20-hydroxyecdysone (20e) increases its titre level during the wandering stage and influences innate immunity in many holometabolous insects. however, the function of 20e as an immune-activator or -suppressor needs to be determined. here, the transcriptome of the peptidoglycan-challenged fat body of the cotton bollworm, helicoverpa armigera, was analysed using illumina sequencing technology. overall, 32 073 unigenes were assembled with a mean length of 643 nucleotides. gene expression dynamics in ... | 2014 | 25224836 |
| cadherin mutation linked to resistance to cry1ac affects male paternity and sperm competition in helicoverpa armigera. | several lepidopteran pests of cotton have cadherin-based resistance to the bacillus thuringiensis (bt) toxin cry1ac. cadherins are transmembrane proteins that mediate cell-cell adhesion and tissue morphogenesis, suggesting that fitness costs associated with cadherin mutations may be present in many aspects of life history. to evaluate whether cadherin-based resistance is associated with fitness costs reducing male paternity in helicoverpa armigera, we examined the effects of a major cadherin res ... | 2014 | 25220924 |
| stable bacillus thuringiensis transgene introgression from brassica napus to wild mustard b. juncea. | transgenic canola (brassica napus) with a bacillus thuringiensis cry1ac gene and a green fluorescent protein (gfp) marker gene was used in hybridization experiments with wild brassica juncea. hybrid f1 and successive five backcross generations were obtained. the pod-set frequency on backcrossed b. juncea plants was over 66%, which suggested relatively high crossing compatibility between the hybrids and wild species. the seed setting in bc1 was the least of all generations tested, and then increa ... | 2014 | 25219305 |
| 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 |
| diversity in gut microflora of helicoverpa armigera populations from different regions in relation to biological activity of bacillus thuringiensis δ-endotoxin cry1ac. | transgenic crops expressing toxin proteins from bacillus thuringiensis (bt) have been deployed on a large scale for management of helicoverpa armigera. resistance to bt toxins has been documented in several papers, and therefore, we examined the role of midgut microflora of h. armigera in its susceptibility to bt toxins. the susceptibility of h. armigera to bt toxin cry1ac was assessed using log-dose-probit analysis, and the microbial communities were identified by 16s rrna sequencing. the h. ar ... | 2014 | 25195523 |
| dual cry2ab and vip3a resistant strains of helicoverpa armigera and helicoverpa punctigera (lepidoptera: noctuidae); testing linkage between loci and monitoring of allele frequencies. | considerable attention has been given to delaying the evolution of insect resistance to toxins produced by transgenic crops. the major pests of cotton in australia are the lepidoptera helicoverpa armigera (hubner, 1805) and helicoverpa punctigera (wallengren), and the toxins deployed in current and imminent transgenic cotton varieties are cry1ac, cry2ab and vip3a from bacillus thuringiensis. in this study, lines that carry alleles conferring resistance to cry2ab and vip3a were isolated using f2 ... | 2014 | 25195454 |
| fitness costs of reproductive capacity and ovarian development in a bt-resistant strain of the cotton bollworm helicoverpa armigera (hübner) (lepidoptera: noctuidae). | the cotton bollworm helicoverpa armigera has developed resistance to the insecticidal cry1ac toxins produced by bacillus thuringiensis (bt) in china. to gain a better understanding of the fitness cost associated with resistance evolution, reproductive capacities and ovarian development were examined in four strains of h. armigera: a cry1ac-susceptible strain (96s); a cry1ac-resistant strain fed on an artificial diet with cry1ac toxin for 135 generations (btr); two strains derived from btr: a str ... | 2015 | 25186022 |
| mis-splicing of the abcc2 gene linked with bt toxin resistance in helicoverpa armigera. | toxins from the bacterium bacillus thuringiensis (bt) are used widely for insect control in sprays and transgenic plants, but their efficacy is reduced when pests evolve resistance. previous work showed that mutations in a gene encoding the transporter protein abcc2 are linked with resistance to bt toxins cry1ab, cry1ac or both in four species of lepidoptera. here we compared the abcc2 gene of helicoverpa armigera (haabcc2) between susceptible strains and a laboratory-selected strain with >1,000 ... | 2014 | 25154974 |
| dna-based screening for an intracellular cadherin mutation conferring non-recessive cry1ac resistance in field populations of helicoverpa armigera. | a number of cadherin mutants conferring resistance to bt toxin cry1ac have been reported in three major lepidopteran pests, including helicoverpa armigera. unlike most of the cadherin mutants conferring recessive resistance, an allele (r15) with a 55aa deletion in the intracellular domain of cadherin (hacad) was previously identified to cause non-recessive resistance to cry1ac in h. armigera. in the present study, a dna-based pcr method was developed to screen the r15 allele from field populatio ... | 2013 | 25149249 |
| baseline sensitivity of maize borers in india to the bacillus thuringiensis insecticidal proteins cry1a.105 and cry2ab2. | among the major pests of maize in india are two stem borers, chilo partellus (swinhoe) and sesamia inferens (walker), and an earworm, helicoverpa armigera (hübner). as a pest control strategy, transgenic bacillus thuringiensis (bt) maize hybrids are undergoing regulatory trials in india. we have determined the sensitivity of the target lepidopterans to the insecticidal bt proteins expressed in bt maize, as this determines product efficacy and the resistance management strategy to be adopted. mai ... | 2015 | 25143318 |
| responses of 9 lepidopteran species to bacillus thuringiensis: how useful is phylogenetic relatedness for selecting surrogate species for nontarget arthropod risk assessment? | to evaluate phylogenetic relatedness as a proxy for susceptibility to bacillus thuringiensis (bt) when selecting species to act as surrogates for others in prerelease testing, we examined the responses of 11 laboratory-reared lepidopteran colonies, comprising members of 2 families, 5 genera, and 9 species, to a commercial bt preparation. survival, pupal mass, and timing of pupation and adult emergence of 2 noctuids (spodoptera litura and helicoverpa armigera) and 7 tortricids (cnephasia jactatan ... | 2015 | 25111652 |
| pigeonpea genotypes influence parasitization preference and survival and development of the helicoverpa armigera larval parasitoid, campoletis chlorideae. | studies were undertaken to identify pigeonpea, cajanus cajan (l.) millspaugh and the wild relative of pigeonpea, cajanus scarabaeoides (l.) (accession icpw 125,) genotypes that are hospitable to the pod borer, helicoverpa armigera (hübner) (lepidoptera: noctuidae) larval parasitoid, campoletis chlorideae uchida (hymenoptera: ichneumonidae) for the management of this pest in pigeonpea based cropping systems. percentage parasitization of the h. armigera larvae by the c. chlorideae females was grea ... | 2014 | 25110629 |
| juvenile hormone prevents 20-hydroxyecdysone-induced metamorphosis by regulating the phosphorylation of a newly identified broad protein. | the steroid hormone 20-hydroxyecdysone (20e) initiates insect molting and metamorphosis. by contrast, juvenile hormone (jh) prevents metamorphosis. however, the mechanism by which jh inhibits metamorphosis remains unclear. in this study, we propose that jh induces the phosphorylation of broad isoform z7 (brz7), a newly identified protein, to inhibit 20e-mediated metamorphosis in the lepidopteran insect helicoverpa armigera. the knockdown of brz7 in larvae inhibited metamorphosis by repressing th ... | 2014 | 25096576 |
| antibiotics influence the toxicity of the delta endotoxins of bacillus thuringiensis towards the cotton bollworm, helicoverpa armigera. | the cotton bollworm, helicoverpa armigera is one of the most important crop pests worldwide. it has developed high levels of resistance to synthetic insecticides, and hence, bacillus thuringiensis (bt) formulations are used as a safer pesticide and the bt genes have been deployed in transgenic crops for controlling this pest. there is an apprehension that h. armigera might develop resistance to transgenic crops in future. therefore, we studied the role of gut microbes by eliminating them with an ... | 2014 | 25059716 |
| 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 |
| quantitative analysis of fitness costs associated with the development of resistance to the bt toxin cry1ac in helicoverpa armigera. | transgenic bacillus thuringiensis (bt) crops play an increasing role in pest control, and resistance management is a major issue in large-scale cultivation of bt crops. the fitness cost of resistance in targeted pests is considered to be one of the main factors delaying resistance when using the refuge strategy. by comparing 10 resistant helicoverpa armigera (hubner) strains, showing various resistance levels to bt toxin (cry1ac), to a susceptible strain, we showed an increasing fitness cost cor ... | 2014 | 25005122 |
| induced resistance by oxidative shifts in pigeonpea (cajanus cajan l.) following helicoverpa armigera (hübner) herbivory. | oxidative responses in leaves, developing seeds and the pod wall of nine pigeonpea genotypes were investigated against helicoverpa armigera feeding. out of nine genotypes, four were moderately resistant, three were intermediate and two were moderately susceptible genotypes. | 2015 | 24974811 |
| evaluation of the synergistic activities of bacillus thuringiensis cry proteins against helicoverpa armigera (lepidoptera: noctuidae). | with the aim of identifying cry proteins that would be useful in the management of the economically important lepidopteran pest helicoverpa armigera, the larvicidal activities of binary combinations (1:1 ratios) of six cry proteins (cry1aa, cry1ab, cry1ac, cry1ca, cry2aa and cry9aa) were evaluated against h. armigera neonate larvae using droplet feeding bioassays. determination of the ld50 values of individual cry proteins and mixtures of cry proteins enabled assessment of the nature of the inte ... | 2014 | 24963598 |
| identification and characterization of the sudanese bacillus thuringiensis and related bacterial strains for their efficacy against helicoverpa armigera and tribolium castaneum. | forty-four isolates of bacillus thuringiensis like bacteria from various sources in different locations from sudan were tested for their insecticidal activity. the toxicity of these isolates ranged from 6.6 to 70% to the neonates of cotton bollworm, helicoverpa armigera at 10 ppm concentration. the most effective ones are kb-29, st-6 and wh-1 comparable with hd-1. toxicity of isolates to larvae of the red flour beetle, tribolium castaneum ranged from 20 to 100%. isolates st-2 and st-23 gave 100% ... | 2014 | 24956895 |
| response of last instar helicoverpa armígera larvae to bt toxin ingestion: changes in the development and in the cyp6ae14, cyp6b2 and cyp9a12 gene expression. | bt crops are able to produce cry proteins, which were originally present in bacillus thuringiensis bacteria. although bt maize is very efficient against corn borers, spanish crops are also attacked by the earworm h. armigera, which is less susceptible to bt maize. many mechanisms could be involved in this low susceptibility to the toxin, including the insect's metabolic resistance to toxins due to cytochrome p450 monooxygenases. this paper examines the response of last instar h. armigera larvae ... | 2014 | 24910993 |
| pirb-cry2aa hybrid protein exhibits enhanced insecticidal activity against spodoptera exigua larvae. | previous study revealed that the n-terminal region of pirb toxin from photorhabdus luminescens showed 20.5% identity and 41.5% similarity to the domain i of cry2a toxin of bacillus thuringiensis. the encoding sequence of the domain i of cry2aa protein was replaced by the encoding gene of corresponding domain of pirb protein. expression of pirb-cry2aa chimeric gene in b. thuringiensis acrystalliferous strain cry(-)b leads to the formation of crystals with irregular shape. bioassay showed that pir ... | 2014 | 24879991 |
| a nonhost peptidase inhibitor of ~14 kda from butea monosperma (lam.) taub. seeds affects negatively the growth and developmental physiology of helicoverpa armigera. | helicoverpa armigera is one of the major devastating pests of crop plants. in this context a serine peptidase inhibitor purified from the seeds of butea monosperma was evaluated for its effect on developmental physiology of h. armigera larvae. b. monosperma peptidase inhibitor on 12% denaturing polyacrylamide gel electrophoresis exhibited a single protein band of ~14 kda with or without reduction. in vitro studies towards total gut proteolytic enzymes of h. armigera and bovine trypsin indicated ... | 2014 | 24860667 |
| characterization of protein phosphatase 5 from three lepidopteran insects: helicoverpa armigera, mythimna separata and plutella xylostella. | protein phosphatase 5 (pp5), a unique member of serine/threonine phosphatases, regulates a variety of biological processes. we obtained full-length pp5 cdnas from three lepidopteran insects, helicoverpa armigera, mythimna separata and plutella xylostella, encoding predicted proteins of 490 (55.98 kda), 490 (55.82 kda) and 491 (56.07 kda) amino acids, respectively. these sequences shared a high identity with other insect pp5s and contained the tpr (tetratricopeptide repeat) domains at n-terminal ... | 2014 | 24823652 |
| 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 |
| monitoring cotton bollworm resistance to cry1ac in two counties of northern china during 2009-2013. | transgenic cotton that expresses a gene derived from the bacterium bacillus thuringiensis (bt) has been deployed for combating cotton bollworm in china since 1997. as a follow-up on research started in 2002, the quantitative shifts in larval cry1ac resistance of field helicoverpa armigera populations were monitored from 2009-2013 using bioassays of isofemale lines. | 2015 | 24753356 |
| central projections of gustatory receptor neurons in the medial and the lateral sensilla styloconica of helicoverpa armigera larvae. | food selection behavior of lepidopteran larvae is predominantly governed by the activation of taste neurons present in two sensilla styloconica located on the galea of the maxilla. in this study, we present the ultrastructure of the sensilla styloconica and the central projection pattern of their associated receptor neurons in larvae of the heliothine moth, helicoverpa armigera. by means of light microscopy and scanning electron microscopy, the previous findings of two morphologically fairly sim ... | 2014 | 24740428 |
| phospholipase cγ1 connects the cell membrane pathway to the nuclear receptor pathway in insect steroid hormone signaling. | in addition to the classical nuclear receptor pathway, there is a nongenomic pathway in the cell membrane that regulates gene expression in animal steroid hormone signaling; however, this mechanism is unclear. here, we report that the insect steroid hormone 20-hydroxyecdysone (20e) regulates calcium influx via phospholipase cγ1 (plcg1) to modulate the protein kinase c phosphorylation of the transcription factor ultraspiracle (usp1) in the lepidopteran insect helicoverpa armigera. the plcg1 mrna ... | 2014 | 24692553 |
| 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 |
| evaluation of total phenolic compounds and insecticidal and antioxidant activities of tomato hairy root extract. | tomatoes are one of the most consumed crops in the whole world because of their versatile importance in dietary food as well as many industrial applications. they are also a rich source of secondary metabolites, such as phenolics and flavonoids. in the present study, we described a method to produce these compounds from hairy roots of tomato (thrs). agrobacterium rhizogenes strain a4 was used to induce hairy roots in the tomato explants. the ri t-dna was confirmed by polymerase chain reaction am ... | 2014 | 24635720 |
| draft genome sequence of bacillus thuringiensis serovar tolworthi strain na205-3, an isolate toxic for helicoverpa armigera. | we report here the complete annotated 6,510,053-bp draft genome sequence of bacillus thuringiensis serovar tolworthi strain na205-3, which is toxic for helicoverpa armigera. this strain potentially contains nine insecticidal toxin genes homologous to cry1aa12, cry1ab1, cry1ab8, cry1ba1, cry1af1, cry1ia10, vip1bb1, vip2ba2, and vip3aa6. | 2014 | 24625875 |
| aldehyde reductase activity in the antennae of helicoverpa armigera. | in the present study, we identified two aldehyde reductase activities in the antennae of helicoverpa species, nadh and nadph-dependent activity. we expressed one of these proteins of h. armigera, aldo-keto reductase (akr), which bears 56% identity to bovine aldose reductase, displays a nadph-dependent activity and is mainly expressed in the antennae of adults. whole-mount immunostaining showed that the enzyme is concentrated in the cells at the base of chemosensilla and in the nerves. the enzyme ... | 2014 | 24580848 |
| differential antibiosis against helicoverpa armigera exerted by distinct inhibitory repeat domains of capsicum annuum proteinase inhibitors. | plant defensive serine proteinase inhibitors (pis) are known to have negative impact on digestive physiology of herbivore insects and thus have a crucial role in plant protection. here, we have assessed the efficacy and specificity of three previously characterized inhibitory repeat domain (ird) variants from capsicum annuum pis viz., ird-7, -9 and -12 against gut proteinases from helicoverpa armigera. comparative study of in silico binding energy revealed that ird-9 possesses higher affinity to ... | 2014 | 24559910 |
| tradeoff between reproduction and resistance evolution to bt-toxin in helicoverpa armigera: regulated by vitellogenin gene expression. | evolution of resistance to insecticides usually has fitness tradeoffs associated with adaptation to the stress. the basic regulation mechanism of tradeoff between reproduction and resistance evolution to bacillus thuringiensis (bt) toxin in the cotton bollworm, helicoverpa armigera (ha), based on the vitellogenin (vg) gene expression was analyzed here. the full-length cdna of the vg gene havg (jx504706) was cloned and identified. havg has 5704 base pairs (bp) with an open reading frame (orf) of ... | 2014 | 24555504 |
| complete genome sequence of agrotis segetum granulovirus shanghai strain. | the complete nucleotide sequence of agrotis segetum granulovirus shanghai strain (agsegv-l1) was determined and compared with that of agsegv xinjiang strain (agsegv-xj). the circular genome of agsegv-l1 is 131,442 bp and has a g+c content of 37.27 %. it includes 149 orfs, 24 of which are unique to agsegv (agsegv-l1 and agsegv-xj [genbank accession no. nc_005839]). the average level of amino acid sequence identity between agsegv-l1 and other granulovirus (gv) homologues (except agsegv-xj) ranged ... | 2014 | 24519461 |
| 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 |
| a screening of five bacillus thuringiensis vip3a proteins for their activity against lepidopteran pests. | five bacillus thuringiensis vip3a proteins (vip3aa, vip3ab, vip3ad, vip3ae and vip3af) and their corresponding trypsin-activated toxins were tested for their toxicity against eight lepidopteran pests: agrotis ipsilon, helicoverpa armigera, mamestra brassicae, spodoptera exigua, spodoptera frugiperda, spodoptera littoralis, ostrinia nubilalis and lobesia botrana. toxicity was first tested at a high dose at 7 and 10 days. no major differences were found when comparing protoxins vs. trypsin-activat ... | 2014 | 24508583 |
| dominant resistance to bt cotton and minor cross-resistance to bt toxin cry2ab in cotton bollworm from china. | evolution of resistance by insect pests threatens the long-term benefits of transgenic crops that produce insecticidal proteins from bacillus thuringiensis (bt). previous work has detected increases in the frequency of resistance to bt toxin cry1ac in populations of cotton bollworm, helicoverpa armigera, from northern china where bt cotton producing cry1ac has been grown extensively for more than a decade. confirming that trend, we report evidence from 2011 showing that the percentage of individ ... | 2013 | 24478804 |
| identification and characterization of a sex peptide receptor-like transcript from the western tarnished plant bug lygus hesperus. | lygus hesperus females exhibit a post-mating behavioural switch that triggers increased egg laying and decreased sexual interest. in drosophila melanogaster, these changes are controlled by sex peptide (sp) and the sex peptide receptor (dmspr). in helicoverpa armigera, spr (haspr) also regulates some post-mating behaviour; however, myoinhibiting peptides (mips) have been identified as the spr ancestral ligand, indicating that spr is a pleiotropic receptor. in the present study, we identified a t ... | 2014 | 24467643 |
| 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 |
| coexpression of the silent cry2ab27 together with cry1 genes in bacillus thuringiensis subsp. aizawai sp41 leads to formation of amorphous crystal toxin and enhanced toxicity against helicoverpa armigera. | the unexpressed cry2ab27 gene of bacillus thuringiensis subsp. aizawai sp41 (sp41) consists of a single open reading frame (orf) of 1902bp encoding for 634 amino acid residues. the cry2ab27 gene appears to be silent due to the lack of promoter and terminator sequences. in this study we fused the cry2ab27 orf with the cry1ab promoter (500bp) and the terminator (300bp) in vector pht304-18z in order to drive the expression of cry2ab27 in both sp41 and an acrystaliferous, b. thuringiensis subsp. thu ... | 2014 | 24412546 |
| combination of endophytic bacillus and beauveria for the management of fusarium wilt and fruit borer in tomato. | most of the approaches for biocontrol of pests and diseases have used a single biocontrol agent as antagonist to a single pest or pathogen. this accounts for the inconsistency in the performance of biocontrol agents. the development of a bioformulation possessing a mixture of bioagents could be a viable option for the management of major pests and diseases in crop plants. | 2014 | 24376014 |
| improved insecticidal toxicity by fusing cry1ac of bacillus thuringiensis with av3 of anemonia viridis. | av3, a neurotoxin of anemonia viridis, is toxic to crustaceans and cockroaches but inactive in mammals. in the present study, av3 was expressed in escherichia coli origami b (de3) and purified by reversed-phase liquid chromatography. the purified av3 was injected into the hemocoel of helicoverpa armigera, rendering the worm paralyzed. then, av3 was expressed alone or fusion expressed with the cry1ac in acrystalliferous strain cry(-)b of bacillus thuringiensis. the shape of cry1ac was changed by ... | 2014 | 24375189 |
| 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 |
| synthetic fusion-protein containing domains of bt cry1ac and allium sativum lectin (asal) conferred enhanced insecticidal activity against major lepidopteran pests. | different transgenic crop plants, developed with δ-endotoxins of bacillus thuringiensis (bt) and mannose-specific plant lectins, exhibited significant protection against chewing and sucking insects. in the present study, a synthetic gene (cry-asal) encoding the fusion-protein having 488 amino acids, comprising di and dii domains from bt cry1ac and allium sativum agglutinin (asal), was cloned and expressed in escherichia coli. ligand blot analysis disclosed that the fusion-protein could bind to m ... | 2014 | 24355805 |
| role of tomato lipoxygenase d in wound-induced jasmonate biosynthesis and plant immunity to insect herbivores. | in response to insect attack and mechanical wounding, plants activate the expression of genes involved in various defense-related processes. a fascinating feature of these inducible defenses is their occurrence both locally at the wounding site and systemically in undamaged leaves throughout the plant. wound-inducible proteinase inhibitors (pis) in tomato (solanum lycopersicum) provide an attractive model to understand the signal transduction events leading from localized injury to the systemic ... | 2013 | 24348260 |
| 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 |
| up-regulated death-associated lim-only protein contributes to fitness costs of bacillus thuringiensis cry1ac resistance in helicoverpa armigera. | the evolution of bacillus thuringiensis (bt) resistance provides a useful pathway for the study of fitness trade-offs associated with stress adaptation. in a previous study, we used cdna-amplification fragment length polymorphism (cdna-alfp) analysis to identify differentially expressed genes (degs) in cry1ac-susceptible (96s) and -resistant (bt-r) helicoverpa armigera larvae. among these degs, a death-associated lim-only protein (hadalp) was identified. in the current study, the full-length cdn ... | 2014 | 24326206 |
| next-generation sequencing-based transcriptome analysis of helicoverpa armigera larvae immune-primed with photorhabdus luminescens tt01. | although invertebrates are incapable of adaptive immunity, immunal reactions which are functionally similar to the adaptive immunity of vertebrates have been described in many studies of invertebrates including insects. the phenomenon was termed immune priming. in order to understand the molecular mechanism of immune priming, we employed illumina/solexa platform to investigate the transcriptional changes of the hemocytes and fat body of helicoverpa armigera larvae immune-primed with the pathogen ... | 2013 | 24302999 |
| molecular cloning and mrna expression of a ryanodine receptor gene in the cotton bollworm, helicoverpa armigera. | ryanodine receptors (ryrs) are the targets of novel diamide insecticides. the cotton bollworm, helicoverpa armigera, is one of the most important cotton pests in the world. in this study, we report the full-length ryr cdna sequence (named as haryr) of h. armigera. the 16,083-bp contiguous sequence encoded 5, 142 amino acid residues, which shares 80% and 78% overall identities with its homologues in nilaparvata lugens (nlryr) and drosophila melanogaster (dmryr), respectively. all hallmarks of ryr ... | 2013 | 24267694 |
| conserved rna cis-elements regulate alternative splicing of lepidopteran doublesex. | doublesex (dsx) is a downstream key regulator in insect sex determination pathway. in drosophila, alternative splicing of dm-dsx gene is sex-specifically regulated by transformer (tra), in which the functional tra promotes female-specific dm-dsx. however, the sex determination pathway in lepidoptera is not well understood; here we focused on alternative splicing of doublesex (dsx) in two agricultural pests, asian corn borer (ostrinia furnacalis) and cotton bollworm (helicoverpa armigera), as wel ... | 2014 | 24239545 |
| changes in the activity and the expression of detoxification enzymes in silkworms (bombyx mori) after phoxim feeding. | silkworm (bombyx mori) is an economically important insect. however, non-cocoon caused by chemical insecticide poisoning has largely hindered the development of sericulture. to explore the roles of detoxification enzymes in b. mori after insecticide poisoning, we monitored the activity changes of cytochrome p450 monooxygenase, glutathione-s-transferase, and carboxylesterase in b. mori midgut and fatbody after phoxim feeding. at the same time, the expression levels of detoxification enzyme-relate ... | 2013 | 24238284 |
| behavioral response of femalehelicoverpa (heliothis)armigera hb. (lepidoptera: noctuidae) moths to synthetic pigeonpea (cajanus cajan l.) kairomone. | femaleh. armigera moths are highly attracted by a steam distillate from pigeonpea plants, one of their main hosts. a mixture of six compounds, all sesquiterpenes (β-caryophyllene,α-humulene,α-guajene,α-muurolene,γ-muurolene, andα-bulnesene), mixed in the proportions as found in the steam distillate, elicited the same behavioral responses (oriented upwind flights and contacts with the odor source) as the steam distillate. onlyα-bulnesene was attractive by itself, but still less than the whole mix ... | 1996 | 24227588 |
| enhanced methanol production in plants provides broad spectrum insect resistance. | plants naturally emit methanol as volatile organic compound. methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. in the present study, we demonstrated that the over-expression of pectin methylesterase, derived from arabidopsis thaliana and aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. methanol content in the leaves of transgenic pl ... | 2013 | 24223989 |
| 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 |
| proteomic and metabolomic profiles of larval hemolymph associated with diapause in the cotton bollworm, helicoverpa armigera. | diapause is programmed developmental arrest coupled with the depression of metabolic activity and the enhancement of stress resistance. pupal diapause is induced by environmental signals and is prepared during the prediapause phase. in the cotton bollworm, helicoverpa armigera, the prediapause phase, which contains two sub-phases, diapause induction and preparation, occurs in the larval stage. here, we performed parallel proteomic and metabolomic analyses on h. armigera larval hemolymph during t ... | 2013 | 24180224 |
| the ha72 core gene of baculovirus is essential for budded virus production and occlusion-derived virus embedding, and amino acid k22 plays an important role in its function. | ha72 of helicoverpa armigera nucleopolyhedrovirus (a homologue of ac78) was identified as a conserved late baculovirus gene and characterized. ha72 localizes in the intranuclear ring zone. by generating mutants, we showed that ha72 is essential for budded virus (bd) production and occlusion-derived virus (odv) embedding. ha72 also interacted with p33, a baculoviral sulfhydryl oxidase. a point mutation of amino acid 22 from lysine to glutamic acid curtailed bv production and precluded odv occlusi ... | 2013 | 24089571 |
| 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 |
| isolation of an orally active insecticidal toxin from the venom of an australian tarantula. | many insect pests have developed resistance to existing chemical insecticides and consequently there is much interest in the development of new insecticidal compounds with novel modes of action. although spiders have deployed insecticidal toxins in their venoms for over 250 million years, there is no evolutionary selection pressure on these toxins to possess oral activity since they are injected into prey and predators via a hypodermic needle-like fang. thus, it has been assumed that spider-veno ... | 2013 | 24039872 |
| in silico identification of cross affinity towards cry1ac pesticidal protein with receptor enzyme in bos taurus and sequence, structure analysis of crystal proteins for stability. | any novel protein introduced into the gm crops need to be evaluated for cross affinity on living organisms. many researchers are currently focusing on the impact of bacillus thuringiensis cotton on soil and microbial diversity by field experiments. in spite of this, in silico approach might be helpful to elucidate the impact of cry genes. the crystal a protein which was produced by bt at the time of sporulation has been used as a biological pesticide to target the insectivorous pests like cry1ac ... | 2013 | 24023423 |
| comparative studies on the effects of bt-transgenic and nontransgenic cotton on arthropod diversity, seedcotton yield and bollworms control. | the effectiveness of commercial bt-cotton in pest management, influence on arthropod diversity, natural enemies, and toxin flow in the insect fauna under field conditions were studied keeping in view the need to assess bioefficacy and biosafety of bt-transgenic cotton. there were no significant differences in oviposition by helicoverpa armigera on bt-transgenic and non-transgenic cottons (9.2 versus 9.6 eggs plants(-100)), while the numbers of h. armigera larvae were significantly more on non-tr ... | 2013 | 24006809 |
| molecular characterization of novel serovars of bacillus thuringiensis isolates from india. | novel bacillus thuringiensis isolates gs4, gn24 and up1 were isolated and characterized by determination of serotyping, insecticidal protein by sds-page, plasmid composition, cry gene content and insect toxicity. serologically two isolates gs4 and up1 were allocated to the h3abce which is a new serovar while isolate gn24 was of h3ab type. isolate gs4 produced flat crystal inclusions while up1 produced cuboidal crystals. pcr analysis found that both isolates contained cry1 and cry1ac genes. the m ... | 2012 | 23997321 |
| an improved pcr-restriction fragment length polymorphism (rflp) method for the identification of cry1-type genes. | the cry1-type genes of bacillus thuringiensis represent the largest cry gene family, which contains 50 distinct holotypes. it is becoming more and more difficult to identify cry1-type genes using current methods because of the increasing number of cry1-type genes. in the present study, an improved pcr-restriction fragment length polymorphism (pcr-rflp) method which can distinguish 41 holotypes of cry1-type genes was developed. this improved method was used to identify cry1-type genes in 20 b. th ... | 2013 | 23995930 |
| 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 |
| antifeedant and larvicidal activities of rhein isolated from the flowers of cassia fistula l. | antifeedant and larvicidal activities of rhein (1,8-dihydroxyanthraquinone-3-carboxylic acid) isolated from the ethyl acetate extract of cassia fistula flower were studied against lepidopteron pests spodoptera litura and helicoverpa armigera. significant antifeedant activity was observed against h. armigera (76.13%) at 1000 ppm concentration. rhein exhibited larvicidal activity against h. armigera (67.5), s. litura (36.25%) and the lc50 values was 606.50 ppm for h. armigera and 1192.55 ppm for s ... | 2011 | 23961115 |