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an ecological genomic approach challenging the paradigm of differential plant responses to specialist versus generalist insect herbivores.a general prediction of the specialist/generalist paradigm indicates that plant responses to insect herbivores may depend on the degree of ecological specialization of the insect attacker. however, results from a single greenhouse experiment evaluating the responses of the model plant arabidopsis thaliana to three specialist (plutella xylostella, pieris rapae, and brevicoryne brassicae) and three generalist (trichoplusia ni, spodoptera exigua, and myzus persicae) insect species did not support t ...201121625984
synergistic effects of cydia pomonella granulovirus gp37 on the infectivity of nucleopolyhedroviruses and the lethality of bacillus thuringiensis.to initiate an efficient primary infection, it is important for baculovirus virions to penetrate through the peritrophic membrane (pm) of the host insect. it is frequently reported that enhancins of baculoviruses significantly enhance viral infection by degrading the various protein components of pms. however, not all baculoviruses encode enhancins. gp37s of baculoviruses share high amino acid identity with fusolins, synergistic factors found in entomopoxviruses. in this study, a truncated cydia ...201121643992
differential performance of a specialist and two generalist herbivores and their parasitoids on plantago lanceolata.the ability to cope with plant defense chemicals differs between specialist and generalist species. in this study, we examined the effects of the concentration of the two main iridoid glycosides (igs) in plantago lanceolata, aucubin and catalpol, on the performance of a specialist and two generalist herbivores and their respective endoparasitoids. development of the specialist herbivore melitaea cinxia was unaffected by the total leaf ig concentration in its host plant. by contrast, the generali ...201121691810
expression of recombinant human interferon-+¦ with antiviral activity in the bi-cistronic baculovirus-insect/larval system.a bi-cistronic baculovirus-insect/larval system containing a polyhedron promoter, an internal ribosome entry site (ires), and an egfp gene was developed as a cost-effective platform for the production of recombinant human interferon gamma (rhifn-+¦). there was no significant difference between the amounts of rhifn-+¦ produced in the baculovirus-infected spodoptera frugiferda 21 cells grown in serum-free medium and the serum-supplemented medium, while the trichoplusia ni (t. ni) and spodoptera ex ...201121737931
cloning of the heat shock protein 90 and 70 genes from the beet armyworm, spodoptera exigua, and expression characteristics in relation to thermal stress and development.two full-length cdnas of heat shock protein (hsp) genes (se-hsp90 and se-hsp70) were cloned from the beet armyworm, spodoptera exigua, and their expression was investigated in relation to cold shock, heat shock, and development. the open reading frames of se-hsp90 and se-hsp70 are 2,154 and 2,004 bp in length, encoding polypeptides of 717 and 667 amino acids with a molecular mass of 82.6 and 72.5 kda, respectively. both genes showed high similarity to their counterparts in other species. transcr ...201121842334
rna interference of β1 integrin subunit impairs development and immune responses of the beet armyworm, spodoptera exigua.integrin is a cell surface protein that is composed of α and β heterodimer and mediates cell interaction with extracellular matrix or other cells including microbial pathogens. a full length cdna sequence (2862 bp) of a β1 subunit integrin (βse1) was cloned from the beet armyworm, spodoptera exigua. phylogenetic analysis showed that βse1 was clustered with other insect β integrin subunits with the highest amino acid sequence identity (98.3%) to β1 of spodoptera litura. structural analysis of the ...201121856307
pge(2) induces oenocytoid cell lysis via a g protein-coupled receptor in the beet armyworm, spodoptera exigua.eicosanoids mediate cellular and humoral immune responses in the beet armyworm, spodoptera exigua, including activation of prophenoloxidase (ppo). ppo activation begins with release of its inactive zymogen, ppo, from oenocytoids in response to prostaglandins (pgs). based on the biomedical literature, we hypothesized that pgs exert their actions via specific g protein-coupled receptor(s) in s. exigua. this study reports a g protein-coupled receptor (se-hcpggpcr1) gene, which is expressed in the h ...201121867708
pea aphids, acyrthosiphon pisum, suppress induced plant volatiles in broad bean, vicia faba.plants defend themselves against herbivory through several means, including the production of airborne volatile organic compounds (vocs). these vocs benefit plants by attracting natural enemies of their herbivores. the pea aphid, acyrthosiphon pisum, is able to feed on its host plant, vicia faba, without inducing detectable changes in plant voc emission. levels of vocs emission are not significantly different between control plants and those fed upon by aphids for up to 5 days. using a second he ...201121870158
[Establishment of SeMNPV persistent infection in Spotoptera exigua cells].Persistent baculovirus infection is observed frequently in insect populations. Persistent infection can be transformed to a replicative and infective state caused by stress factors and plays an important role in regulating the size of insect population and in epizoology of baculoviruses. The aim of this study is to establish a persistently baculovirus-infected cell system to explore the molecular mechanisms of baculoviral persistence. Spodoptera exigua nucleopolyhedrovirus (SeMNPV) was serially ...201121874904
long-term effects of methoxyfenozide on the adult reproductive processes and longevity of spodoptera exigua (lepidoptera: noctuidae).the long-term effects of methoxyfenozide on the longevity and reproductive processes of beet armyworm, spodoptera exigua (hübner) (lepidoptera: noctuidae), adults were assessed after exposure by ingestion. methoxyfenozide significantly reduced adult male longevity compared with females by 1.1 and 1.5 d at 75 and 150 mg (ai)/liter, respectively. fecundity decreased by >60% with both concentrations at 72 and 96 h after treatment, but at 48 h, no significant effect was observed. the carbohydrate, p ...201121882687
RNA interference of an antimicrobial peptide, gloverin, of the beet armyworm, Spodoptera exigua, enhances susceptibility to Bacillus thuringiensis.Gloverin is known to be an inducible antimicrobial peptide. This study reports a gloverin gene (Seglv) identified from the beet armyworm, Spodoptera exigua. Seglv encodes 175 amino acids with a signal peptide. Its amino acid sequence is highly homologous (>95%) to other known gloverins. Seglv was expressed from egg to adult stages even without immune challenge. Especially, in larval stage, it was expressed in all tested tissues, such as hemocyte, fat body, gut, and epidermis. However, the consti ...201121925182
plasmatocyte-spreading peptide influences hemocyte behavior via eicosanoids.hemocyte-spreading behavior is required for expressing a cellular immune response, nodulation, which clears the vast majority of invading microbes from circulation. the nodulation response is completed by a layer of plasmatocytes, which spread over the nodule and initiate a malanization process leading to darkened nodules. plasmatocyte-spreading peptide (psp), the first reported insect cytokine, is responsible for mediating the spreading and attachment of some subclasses of plasmatocytes to nodu ...201122006534
genome sequence of seiv-1, a novel virus from the iflaviridae family infective to spodoptera exigua.analysis of the transcriptome of spodoptera exigua larvae revealed the presence of several ests with homology to virus of the order picornavirales and with the highest similarity to infectious flacherie virus (iflaviridae) that infects bombyx mori larvae. iflaviridae is a recently defined family of insect-infecting viruses that consist of positive single strand rna genomes translated into a single polyprotein of around 3000 amino acids long. using the sequence information derived from the obtain ...201222041201
pinellia ternata agglutinin expression in chloroplasts confers broad spectrum resistance against aphid, whitefly, lepidopteran insects, bacterial and viral pathogens.broad spectrum protection against different insects and pathogens requires multigene engineering. however, such broad spectrum protection against biotic stress is provided by a single protein in some medicinal plants. therefore, tobacco chloroplasts were transformed with the agglutinin gene from pinellia ternata (pta), a widely cultivated chinese medicinal herb. pinellia ternata agglutinin (pta) was expressed up to 9.2% of total soluble protein in mature leaves. purified pta showed similar hemag ...201122077160
Rapid detection of vip1-type genes from Bacillus cereus and characterization of a novel vip binary toxin gene.A PCR-restriction fragment length polymorphism (PCR-RFLP) method for identifying vegetative insecticidal protein (vip) 1-type genes from Bacillus cereus was developed by designing specific primers based on the conserved regions of the genes to amplify vip1-type gene fragments. PCR products were digested with endonuclease AciI, and four known vip1-type genes were identified. Vip1Ac and vip1Aa-type genes appeared in 17 of 26 B. cereus strains. A novel vip1-type gene, vip1Ac1, was identified from B ...201122092859
avian conservation practices strengthen ecosystem services in california vineyards.insectivorous western bluebirds (sialia mexicana) occupy vineyard nest boxes established by california winegrape growers who want to encourage avian conservation. experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. we compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without ne ...201122096555
plant sterols and host plant suitability for generalist and specialist caterpillars.insects, unlike plants and vertebrates, lack the ability to biosynthesize sterols. cholesterol is typically the most common sterol found in plant-feeding insects, but it is rarely found in plants above trace levels, so plant-feeding insects must produce the cholesterol they need by metabolizing the sterols found in the plants they eat. plant-feeding insects are, however, often limited in terms of which sterols can be converted to cholesterol. in the current study we used a transgenic tobacco pla ...201122154836
characterization and expression of attacin, an antibacterial protein-encoding gene, from the beet armyworm, spodoptera exigua (hübner) (insecta: lepidoptera: noctuidae).to isolate antimicrobial-related genes from the beet armyworm, spodoptera exigua, we performed genefishing, a polymerase chain reaction (pcr)-based differential display technique. an attacin-like complementary dna (cdna) including a 3'-untranslated region was identified from among 18 over-expressed genes in microbial-infected larvae. the full-length attacin cdna from s. exigua cdna (seattacin) was cloned using rapid amplification of cdna ends pcr. the attacin-like cdna transcript was 765 nucleot ...201122160467
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 ...201222193392
co-expression and synergism analysis of vip3aa29 and cyt2aa3 insecticidal proteins from bacillus thuringiensis.vegetative insecticidal protein (vip3) from bacillus thuringiensis shows high activity against lepidopteran insects. cytolytic δ-endotoxin (cyt) also has high toxicity to dipteran larvae and synergism with other crystal proteins (cry), but synergism between cyt and vip3 proteins has not been tested. we analyzed for synergism between cyt2aa3 and vip3aa29. both cyt2aa3 and vip3aa29 genes were co-expressed in escherichia coli strain bl21 carried on vector pcoladuet-1. vip3aa29 showed insecticidal a ...201222218570
long-term foliar persistence and efficacy of spinosad against beet armyworm under greenhouse conditions.the immediate lethality caused by spinosad has been widely studied on spodoptera exigua (hübner). however, long-term effects can also provide valuable information on insecticide toxic action. here, the persistence of spinosad on capsicum annuum l. foliage and the lethal and sublethal effects of greenhouse-aged foliar residues of this insecticide on third instars of s. exigua are reported.201222262560
effects of glucosinolates on a generalist and specialist leaf-chewing herbivore and an associated parasitoid.glucosinolates (gls) are secondary plant metabolites that as a result of tissue damage, for example due to herbivory, are hydrolysed into toxic compounds that negatively affect generalist herbivores. specialist herbivores have evolved specific adaptations to detoxify gls or inhibit the formation of toxic hydrolytic products. although rarely studied, gls and their breakdown products may also affect parasitoids. the objectives were to test the effects of gls in a multitrophic system consisting of ...201222281379
transcriptional activity and nuclear localization of cabut, the drosophila ortholog of vertebrate tgf-β-inducible early-response gene (tieg) proteins.cabut (cbt) is a c(2)h(2)-class zinc finger transcription factor involved in embryonic dorsal closure, epithelial regeneration and other developmental processes in drosophila melanogaster. cbt orthologs have been identified in other drosophila species and insects as well as in vertebrates. indeed, cbt is the drosophila ortholog of the group of vertebrate proteins encoded by the tgf-ß-inducible early-response genes (tiegs), which belong to sp1-like/krüppel-like family of transcription factors. se ...201222359651
genetic basis of destruxin production in the entomopathogen metarhizium robertsii.destruxins are among the most exhaustively researched secondary metabolites of entomopathogenic fungi, yet definitive evidence for their roles in pathogenicity and virulence has yet to be shown. to establish the genetic bases for the biosynthesis of this family of depsipeptides, we identified a 23,792-bp gene in metarhizium robertsii arsef 2575 containing six complete nonribosomal peptide synthetase modules, with an n-methyltransferase domain in each of the last two modules. this domain arrangem ...201222367459
hydrophobin genes of the entomopathogenic fungus, metarhizium brunneum, are differentially expressed and corresponding mutants are decreased in virulence.hydrophobins are small, cysteine-rich, secreted proteins, ubiquitously produced by filamentous fungi that are speculated to function in fungal growth, cell surface properties, and development, although this has been rigorously tested for only a few species. herein, we report identification of three hydrophobin genes from the entomopathogenic fungus, metarhizium brunneum, and functional characterization of strains lacking these genes. one gene (hyd1/ssga) encodes a class i hydrophobin identified ...201222388867
functional interactions between members of the repat family of insect pathogen-induced proteins.studies on the transcriptional response to pathogens in the insect larval gut have shown the regulation of several genes after the infection. repat (response to pathogens) genes were first identified in spodoptera exigua midgut as being up-regulated in response to the exposure to bacillus thuringiensis toxins and baculovirus. recently, new members of the repat family showed a constitutive up-regulation in a b. thuringiensis-resistant population. based on a yeast two-hybrid screening, we have det ...201222404489
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.201222447600
functional analysis of two chitinase genes during the pupation and eclosion stages of the beet armyworm spodoptera exigua by rna interference.insect chitinases are a multigene family that is encoded by a rather large and diverse group of genes. the main function of chitinases is to digest the chitin contained in tissues such as the cuticles and gut lining during molting. in this study, we examined the role of a chitinase (sechi) and a bacterial type chitinase (sechi-h) during the pupation and eclosion stages of spodoptera exigua. first, efficient silencing of the sechi and sechi-h genes through specific double-stranded rna (dsrna) inj ...201222460420
demographic parameters of spodoptera exigua (lepidoptera: noctuidae) on different soybean cultivars.life table, reproduction, and population growth parameters of the beet armyworm, spodoptera exigua (hübner) (lepidoptera: noctuidae), were determined on nine soybean (glycine max l.) cultivars ('032', '033', 'hill', 'm4', 'm7', 'm9', 'm11', 'tms', and 'zane') at 25°c. the age-specific survival rate of eggs and immature stages was higher on 033 in comparison with other cultivars. the gross fecundity rate ranged from 911 on m9 to 1,296 on zane, but the differences were not statistically significan ...201222507005
responses of arabidopsis thaliana plant lines differing in hydroxylation of aliphatic glucosinolate side chains to feeding of a generalist and specialist caterpillar.plants contain variable chemical compositions which play a role in direct defense against phytophagous insects. glucosinolates (gss) are the predominant secondary metabolites and defense compounds in brassicaceous species. as a consequence of co-evolution between adapted crucifer-feeding specialists and their associated host-plants, specific plant-insect interactions have developed in a divergent manner from non-adapted generalists. therefore, generalist and specialist insects may provoke differ ...201222543106
expression and characterization of a recombinant cry1ac crystal protein fused with an insect-specific neurotoxin ω-actx-hv1a in bacillus thuringiensis.in order to assess possible enhancement of biopesticide activity, the fusion gene of crystal protein gene cry1ac with the insect-specific neurotoxin ω-actx-hv1a gene and egfp was expressed in bacillus thuringiensis acrystalliferous strain cry-b under the control of the native gene expression system. the fusion recombinant cry-b(1ac-actx-egfp) generally produced two or three small crystal-like inclusion bodies in each cell and the gfp signal could be clearly observed. a 166 kda full-length fusion ...201222548233
salivary glucose oxidase from caterpillars mediates the induction of rapid and delayed-induced defenses in the tomato plant.caterpillars produce oral secretions that may serve as cues to elicit plant defenses, but in other cases these secretions have been shown to suppress plant defenses. ongoing work in our laboratory has focused on the salivary secretions of the tomato fruitworm, helicoverpa zea. in previous studies we have shown that saliva and its principal component glucose oxidase acts as an effector by suppressing defenses in tobacco. in this current study, we report that saliva elicits a burst of jasmonic aci ...201222558369
the transcriptome of spodoptera exigua larvae exposed to different types of microbes.we have obtained and characterized the transcriptome of spodoptera exigua larvae with special emphasis on pathogen-induced genes. in order to obtain a highly representative transcriptome, we have pooled rna from diverse insect colonies, conditions and tissues. sequenced cdna included samples from 3 geographically different colonies. enrichment of rna from pathogen-related genes was accomplished by exposing larvae to different pathogenic and non-pathogenic microbial agents such as the bacteria ba ...201222564783
eicosanoid biosynthesis is activated via toll, but not imd signal pathway in response to fungal infection.phospholipase a(2) (pla(2)) catalyzes hydrolysis of phospholipids at sn-2 position and usually releases arachidonic acid, which is oxygenated into various eicosanoids that mediate innate immune responses in insects. pla(2) activities were measured in both immune-associated tissues of hemocyte and fat body in the beet armyworm, spodoptera exigua. upon challenge of an entomopathogenic fungus, beauveria bassiana, the pla(2)s were significantly activated in both hemocyte and fat body. the fungal inf ...201222569137
improvement of pest resistance in transgenic tobacco plants expressing dsrna of an insect-associated gene ecr.the adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. recently, transgenic plant expressing double-stranded rna (dsrna) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. the steroid hormone, 20-hydroxyecdysone (20e), predominately controls insect molting via its nuclear receptor complex, ecr-usp. here we report that pest resistance is improved in transgenic tobacco ...201222685585
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, ...201222792245
baculovirus lymantria dispar multiple nucleopolyhedrovirus iap2 and iap3 do not suppress apoptosis, but trigger apoptosis of insect cells in a transient expression assay.ld652y cells derived from the gypsy moth, lymantria dispar, are permissive for productive infection with l. dispar multiple nucleopolyhedrovirus (ldmnpv), but undergo apoptosis upon infection with various other npvs, including those isolated from bombyx mori, hyphantria cunea, spodoptera exigua, orgyia pseudotsugata, and spodoptera litura. in this study, we examined whether ldmnpv-encoded inhibitor of apoptosis 2 (ld-iap2) and 3 (ld-iap3) are involved in apoptosis suppression in ldmnpv-infected ...201222798056
manduca sexta gloverin binds microbial components and is active against bacteria and fungi.hyalophora gloveri gloverin is a glycine-rich and heat stable antimicrobial protein with activity mainly against escherichia coli. however, spodoptera exigua gloverin is active against a gram-positive bacterium but inactive against e. coli. in this study, we investigated expression profile, binding ability and antimicrobial activity of manduca sexta gloverin (msglv). msglv transcript was detected in several tissues of naïve larvae with higher levels in the midgut and testis. expression of msglv ...201222858411
analysis of genes expression of spodoptera exigua larvae upon acmnpv infection.the impact of autographa californica multicapsid nucleopolyhedrovirus (acmnpv) infection on host gene expression in spodoptera exigua 4th instar larvae was investigated through the use of 454 sequencing-based rna-seq of cdna libraries developed from insects challenged with active acmnpv or heat-inactivated acmnpv.201222860129
a new cell line (ntu-se) from pupal tissues of the beet armyworm, spodoptera exigua (lepidoptera: noctuidae), is highly susceptible to s. exigua multiple nucleopolyhedrovirus (semnpv) and autographa californica mnpv (acmnpv).a new continuous cell line, ntu-se, was established from the pupal tissues of an economically important pest, the beet armyworm spodoptera exigua (lepidoptera: noctuidae). this cell line contains four major morphologic types: round, polymorphic, spindle-shaped, and comma-shaped cells. the population doubling time of this new line in tnm-fh medium supplemented with 8% fetal bovine serum (fbs) at 28°c is 35.5h. the chromosomal spread from ntu-se cells is typical to the chromosomal morphology of le ...201222867846
rna interference of broad gene expression mimics antimetamorphic effect of pyriproxyfen on the beet armyworm, spodoptera exigua.a larva-to-pupa metamorphosis is induced by a low or undetectable level of juvenile hormone (jh) during last instar in holometabolous insects. an exogenous application of jh agonist, pyriproxyfen (pyr), inhibited pupal metamorphosis of the beet armyworm, spodoptera exigua. last instar larvae of s. exigua exhibited increase of body size at first 3 days along with active feeding behavior. also, at this period, prothoracic gland increased in size, while corpora allata remained little change. storag ...201222899018
phospholipase a₂ inhibitors in bacterial culture broth enhance pathogenicity of a fungus nomuraea rileyi.an entomopathogenic fungus, nomuraea rileyi, was isolated and its identity was confirmed by its internal transcribed spacer dna sequence. the isolated n. rileyi exhibited a specific pathogenicity to lepidopteran species. this study was focused on enhancing the fungal pathogenicity by using immunosuppressive agents. in response to infection of n. rileyi, spodoptera exigua larvae significantly induced catalytic activity of phospholipase a(2) (pla(2)) in three immune-associated tissues, namely hemo ...201222923114
the utility of camptothecin as a synergist of bacillus thuringiensis var. kurstaki and nucleopolyhedroviruses against trichoplusia ni and spodoptera exigua.we studied the effect of combining microbial pesticides with camptothecin (cpt) on the mortality of two lepidopteran insects: trichoplusia ni (hübner) and spodoptera exigua (hübner). cpt is an alkaloid that is often used as an anticancer agent. here, cpt was evaluated as a microbial pesticide synergist of bacillus thuringiensis (bt) and insect baculovirus. the toxicity of cpt and its synergistic effects on two microbial pesticides were studied using the diet overlay method. bioassay results show ...201222928294
projecting overwintering regions of the beet armyworm, spodoptera exigua in china using the climex model.the beet armyworm, spodoptera exigua hübner (lepidoptera: noctuidae) is a serious agricultural pest worldwide. however, population sources of s. exigua in outbreak regions are still vague due to the lack of understanding the distribution of overwintering regions, especially in china. in the present study, the potential overwintering regions of s. exigua in china are projected using the method of compare location in the climex model in order to understand the population sources in outbreak region ...022934543
validation of reference genes for quantitative expression analysis by real-time rt-pcr in four lepidopteran insects.quantitative real-time polymerase chain reaction (qpcr) is an efficient and widely used technique to monitor gene expression. housekeeping genes (hkgs) are often empirically selected as the reference genes for data normalization. however, the suitability of hkgs used as the reference genes has been seldom validated. here, six hkgs were chosen (actin a3, actin a1, gapdh, g3pdh, e2f, rp49) in four lepidopteran insects bombyx mori l. (lepidoptera: bombycidae), plutella xylostella l. (plutellidae), ...201222938136
elongation factor 1β' gene from spodoptera exigua: characterization and function identification through rna interference.elongation factor (ef) is a key regulation factor for translation in many organisms, including plants, bacteria, fungi, animals and insects. to investigate the nature and function of elongation factor 1β' from spodoptera exigua (seef-1β'), its cdna was cloned. this contained an open reading frame of 672 nucleotides encoding a protein of 223 amino acids with a predicted molecular weight of 24.04 kda and pi of 4.53. northern blotting revealed that seef-1β' mrna is expressed in brain, epidermis, fa ...201222942694
the complete mitochondrial genome of the beet armyworm spodoptera exigua (hübner) (lepodiptera: noctuidae).the complete mitochondrial genome of the beet armyworm spodoptera exigua (hübner) (lepodiptera: noctuidae) was determined (genbank accession number jx316220). the genome is 15,365 bp long with 37 typical animal mitochondrial genes and an a+t-rich region. as in other sequenced mitochondrial genomes of lepidoptera, trnm was rearranged to the upstream of trni-trnq-trnm cluster compared with the pupative ancestral arrangement of insects. all protein-coding genes start with atn start codon except for ...201322954158
a new gene superfamily of pathogen-response (repat) genes in lepidoptera: classification and expression analysis.repat (response to pathogens) genes were first identified in the midgut of spodoptera exigua (lepidoptera: noctuidae) in response to bacillus thuringiensis and baculovirus exposure. since then, additional repat gene homologs have been identified in different studies. in this study the comprehensive larval transcriptome from s. exigua was analyzed for the presence of novel repat-homolog sequences. these analyses revealed the presence of at least 46 repat genes in s. exigua, establishing a new gen ...201323036664
neurobactrus, a novel, highly effective, and environmentally friendly recombinant baculovirus insecticide.a novel recombinant baculovirus, neurobactrus, was constructed to develop an improved baculovirus insecticide with additional beneficial properties, such as a higher insecticidal activity and improved recovery, compared to wild-type baculovirus. for the construction of neurobactrus, the bacillus thuringiensis crystal protein gene (here termed cry1-5) was introduced into the autographa californica nucleopolyhedrovirus (acmnpv) genome by fusion of the polyhedrin-cry1-5-polyhedrin genes under the c ...201323064343
metabolic and transcriptomic changes induced in arabidopsis by the rhizobacterium pseudomonas fluorescens ss101.systemic resistance induced in plants by nonpathogenic rhizobacteria is typically effective against multiple pathogens. here, we show that root-colonizing pseudomonas fluorescens strain ss101 (pf.ss101) enhanced resistance in arabidopsis (arabidopsis thaliana) against several bacterial pathogens, including pseudomonas syringae pv tomato (pst) and the insect pest spodoptera exigua. transcriptomic analysis and bioassays with specific arabidopsis mutants revealed that, unlike many other rhizobacter ...201223073694
protein tyrosine phosphatase-induced hyperactivity is a conserved strategy of a subset of baculoviruses to manipulate lepidopteran host behavior.many parasites manipulate host behavior to increase the probability of transmission. to date, direct evidence for parasitic genes underlying such behavioral manipulations is scarce. here we show that the baculovirus autographa californica nuclear polyhedrovirus (acmnpv) induces hyperactive behavior in spodoptera exigua larvae at three days after infection. furthermore, we identify the viral protein tyrosine phosphatase (ptp) gene as a key player in the induction of hyperactivity in larvae, and s ...201223077534
genomic sequence of heliothis virescens ascovirus 3g isolated from spodoptera exigua.heliothis virescens ascovirus 3a (hvav-3a), a member of the family ascoviridae, has the highest diversity among ascovirus species that have been reported in australia, indonesia, china, and the united states. to understand the diversity and origin of this important ascovirus, the complete genome of the hvav indonesia strain (hvav-3g), isolated from spodoptera exigua, was determined to be 199,721 bp, with a g+c content of 45.9%. therefore, hvav-3g has the largest genome among the reported ascovir ...201223087124
construction and characterisation of an antifungal recombinant bacillus thuringiensis with an expanded host spectrum.a novel antifungal bacillus thuringiensis strain 19-22, ssp. kurstaki (h3a3b3c), was characterised. this strain included cry1aa, cry1ab, cry1ac, and cry1d, which have high insecticidal activities against lepidopteran larvae other than spodoptera exigua. to expand the host spectrum, a cry1e gene whose product is active against s. exigua was introduced into the isolate. the transformant successfully expressed the cry1e protein without any loss of its original antifungal activities. these results i ...201223124760
interspecific interaction between spodoptera exigua multiple nucleopolyhedrovirus and microplitis bicoloratus (hymenoptera: braconidae: microgastrina) in spodoptera exigua (lepidoptera: noctuidae) larvae.baculoviruses and parasitoids are important biological control factors of insects in integrated pest management. microplitis bicoloratus chen (hymenoptera: braconidae: microgastrina) is a solitary endoparasitoid of beet armyworm, spodoptera exigua (hübner) (lepidoptera: noctuidae) larvae. m. bicoloratus parasitized first to third instars of s. exigua and most effectively parasitized second instars. the survival rate of parasitoids emerging from s. exigua multiple nucleopolyhedrovirus (semnpv)-in ...201223156143
evaluation of corn hybrids expressing cry1f, cry1a.105, cry2ab2, cry34ab1/cry35ab1, and cry3bb1 against southern united states insect pests.studies were conducted across the southern united states to characterize the efficacy of multiple bacillus thuringiensis (bt) events in a field corn, zea mays l., hybrid for control of common lepidopteran and coleopteran pests. cry1f protein in event tc1507 and cry1a.105 + cry2ab2 proteins in event mon 89034 were evaluated against pests infesting corn on above-ground plant tissue including foliage, stalks, and ears. cry34ab1/cry35ab1 proteins in event das-59122-7 and cry3bb1 in event mon 88017 w ...201223156183
toll recognition signal activates oenocytoid cell lysis via a crosstalk between plasmatocyte-spreading peptide and eicosanoids in response to a fungal infection.plasmatocyte-spreading peptide (psp) activates hemocyte-spreading behavior in response to various microbial pathogens. its homolog, growth-blocking peptide, has several functions that activate immune cells and induce oenocytoid cell lysis (ocl). ocl is required for release of prophenoloxidase from oenocytoids in the beet armyworm, spodoptera exigua. injection of psp to s. exigua larvae significantly induced in vivo ocl and resulted in significant increase of phenoloxidase (po) activity. a fungal ...201223220607
enhanced antibacterial activity of an attacin-coleoptericin hybrid protein fused with a helical linker.previously, we isolated and characterized attacin from spodoptera exigua and a coleoptericin-like protein from protaetia brevitarsis seulensis. in this study, we fused these two genes encoding antimicrobial proteins to obtain a hybrid protein with enhanced antimicrobial activity. to fuse the two antimicrobial proteins, we employed helical and non-helical linker sequences that function as inter-domain linkers in proteins. we used the gly-gly-gly-gly-ser peptide as a non-helical linker. the hybrid ...201223271135
insights into the insect salivary gland proteome: diet-associated changes in caterpillar labial salivary proteins.the primary function of salivary glands is fluid and protein secretion during feeding. compared to mammalian systems, little is known about salivary protein secretion processes and the effect of diet on the salivary proteome in insect models. therefore, the effect of diet nutritional quality on caterpillar labial salivary gland proteins was investigated using an unbiased global proteomic approach by nanolc/esi/tandem ms. caterpillars of the beet armyworm, spodoptera exigua hübner, were fed one o ...201323353727
comparative evaluation of phenoloxidase activity in different larval stages of four lepidopteran pests after exposure to bacillus thuringiensis.microbial entomopathogen-based bioinsecticides are recognized as alternatives to synthetic pesticides. insects defend themselves against microbial pathogens by innate mechanisms, including increased phenoloxidase (po) activity, but its relationship with microbial bioinsecticides efficacy is little known. this study evaluated the differences in po activity at different developmental stages of the tobacco budworm heliothis virescens fabricius (lepidoptera: noctuidae), indian meal moth plodia inter ...201223414117
altered lipid composition and enhanced nutritional value of arabidopsis leaves following introduction of an algal diacylglycerol acyltransferase 2.enhancement of acyl-coa-dependent triacylglycerol (tag) synthesis in vegetative tissues is widely discussed as a potential avenue to increase the energy density of crops. here, we report the identification and characterization of chlamydomonas reinhardtii diacylglycerol acyltransferase type two (dgtt) enzymes and use dgtt2 to alter acyl carbon partitioning in plant vegetative tissues. this enzyme can accept a broad range of acyl-coa substrates, allowing us to interrogate different acyl pools in ...201323417035
characterization of dna topoisomerase-1 in spodoptera exigua for toxicity evaluation of camptothecin and hydoxy-camptothecin.camptothecin (cpt), a plant alkaloid originally isolated from the native chinese tree, camptotheca acuminate, exerts the toxic effect by targeting eukaryotic dna topoisomerase 1 (dna topo1). besides as potent anti-cancer agents, cpt and its derivatives are now being explored as potential pesticides for insect control. in this study, we assessed their toxicity to an insect homolog, the topo1 protein from beet armyworms (spodoptera exigua hübner), a worldwide pest of many important crops. the s. e ...201323451051
identification and tissue distribution of odorant binding protein genes in the beet armyworm, spodoptera exigua.odorant binding proteins (obps) contribute to the remarkable sensitivity of the insect's olfactory system and play an important role in insect chemical communication. in this study, we identified 11 putative cdnas encoding obps (namely sexiobp1-11) from the antennal full length cdna library of the beet armyworm spodoptera exigua (lepidoptera: noctuidae) and examined their expression profiles in different adult body tissues (antennae, heads, thoraxes, abdomens, legs and wings) by real-time quanti ...201323499610
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.201323564718
toxicity of allyl esters in insect cell lines and in spodoptera littoralis larvae.we investigated the effects of five allyl esters, two aromatic (allyl cinnamate and allyl 2-furoate) and three aliphatic (allyl hexanoate, allyl heptanoate, and allyl octanoate) in established insect cell lines derived from different species and tissues. we studied embryonic cells of the fruit fly drosophila melanogaster (s2) (diptera) and the beet armyworm spodoptera exigua (se4) (lepidoptera), fat body cells of the colorado potato beetle leptinotarsa decemlineata (cpb) (coleoptera), ovarian ce ...201223589218
arabidopsis redox status in response to caterpillar herbivory.plant responses to insect herbivory are regulated through complex, hormone-mediated interactions. some caterpillar species have evolved strategies to manipulate this system by inducing specific pathways that suppress plant defense responses. effectors in the labial saliva (ls) secretions of spodoptera exigua caterpillars are believed to induce the salicylic acid (sa) pathway to interfere with the jasmonic acid (ja) defense pathway; however, the mechanism underlying this subversion is unknown. si ...201323653629
rac1 mediates cytokine-stimulated hemocyte spreading via prostaglandin biosynthesis in the beet armyworm, spodoptera exigua.cell spreading is an integral component of insect hemocytic immune reactions to infections and invasions. cell spreading is accomplished by cytoskeleton rearrangement, which is activated by three major immune mediators, biogenic monoamines, plasmatocyte-spreading peptide (psp), and eicosanoids, particularly prostaglandin e2 (pge2). however, little is known about how these immune mediators activate hemocyte spreading at the intra-cellular level. a small g protein, rac1, acts in cytoskeleton arran ...201323660478
a bhlh-type transcription factor, aba-inducible bhlh-type transcription factor/ja-associated myc2-like1, acts as a repressor to negatively regulate jasmonate signaling in arabidopsis.jasmonates (jas) are plant hormones that regulate the balance between plant growth and responses to biotic and abiotic stresses. although recent studies have uncovered the mechanisms for ja-induced responses in arabidopsis thaliana, the mechanisms by which plants attenuate the ja-induced responses remain elusive. here, we report that a basic helix-loop-helix-type transcription factor, aba-inducible bhlh-type transcription factor/ja-associated myc2-like1 (jam1), acts as a transcriptional represso ...201323673982
increased long-flight activity triggered in beet armyworm by larval feeding on diet containing cry1ac protoxin.evaluating ecological safety and conducting pest risk analysis for transgenic crops are vitally important before their commercial planting. the beet armyworm, spodoptera exigua, a long-distance migratory insect pest, is not a direct target of transgenic cry1ac-expressing cotton in china, but nevertheless it has recently become an important pest. migrants leaving their natal field arrive in other appropriate habitat far away in a short time, often followed by larval outbreaks. s. exigua has low s ...201323675489
increase in gut microbiota after immune suppression in baculovirus-infected larvae.spodoptera exigua microarray was used to determine genes differentially expressed in s. exigua cells challenged with the species-specific baculovirus semnpv as well as with a generalist baculovirus, acmnpv. microarray results revealed that, in contrast to the host transcriptional shut-off that is expected during baculovirus infection, s. exigua cells showed a balanced number of up- and down-regulated genes during the first 36 hours following the infection. many immune-related genes, including pa ...201323717206
developmental regulation and antifungal activity of a growth-blocking peptide from the beet armyworm spodoptera exigua.insect cytokine growth-blocking peptides (gbps) are involved in growth regulation and the innate immune response. however, the microbial binding and antimicrobial activities of gbps remain unclear. here, we investigate the developmental role and antifungal activity of a gbp from the beet armyworm spodoptera exigua (segbp). sequence analysis predicted that mature segbp consists of 24 amino acid residues, including 2 cysteine residues. during s. exigua development, segbp is constitutively expresse ...201323732405
an entomopathogenic bacterium, xenorhabdus nematophila, suppresses expression of antimicrobial peptides controlled by toll and imd pathways by blocking eicosanoid biosynthesis.immune-associated genes of the beet armyworm, spodoptera exigua, were predicted from 454 pyrosequencing transcripts of hemocytes collected from fifth instar larvae challenged with bacteria. out of 22,551 contigs and singletons, 36% of the transcripts had at least one significant hit (e-value cutoff of 1e-20) and used to predict immune-associated genes implicated in pattern recognition, prophenoloxidase activation, intracellular signaling, and antimicrobial peptides (amps). immune signaling and a ...201323740621
identification and functional characterization of sex pheromone receptors in beet armyworm spodoptera exigua (hübner).in moths, males can detect a distinct blend of several pheromone components by specialized olfactory receptor neurons (orns) on the antennae. four candidate pheromone receptors (pr) with seven transmembrane domains were identified by homology cloning from the antennae of spodoptera exigua (sexi). phylogenetic analyses reveal that all four odorant receptors (or) belong to pheromone receptor subtypes. expression patterns revealed that prs were male-specific in the antenna except for sexior11, whic ...201323751753
antioxidant enzyme influences germination, stress tolerance, and virulence of isaria fumosorosea.antioxidizing enzymes (superoxide dismutase, catalase, and glutathione peroxidae) are important enzymatic systems used to degrade hydrogen peroxide into water and oxygen, thereby lowering intracellular hydrogen peroxide levels. entomopathogenic fungi display increased activities of antioxidizing enzymes during growth and germination, which is necessary to counteract the hyperoxidant state produced by oxidative metabolism. we studied the influence of different carbon sources on antioxidizing enzy ...201323756951
degradation of rrna in bm-n cells from the silkworm bombyx mori during abortive infection with heterologous nucleopolyhedroviruses.cell lines derived from the silkworm, bombyx mori, are only permissive for b. mori nucleopolyhedrovirus (npv), with other npvs generally resulting in abortive infection. here, we demonstrate that rrna of b. mori bm-n cells undergoes rapid degradation through site-specific cleavage upon infection with npvs from autographa californica (acmnpv), hyphantria cunea (hycumnpv), spodoptera exigua (semnpv) and spodoptera litura (spltmnpv). no significant decreases in cellular rna were observed in ld652y, ...201323784443
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 ...201323786046
application of a frequency distribution method for determining instars of the beet armyworm (lepidoptera: noctuidae) from widths of cast head capsules.instar determination of field-collected insect larvae has generally been based on the analysis of head capsule width frequency distributions or bivariate plotting, but few studies have tested the validity of such methods. we used head capsules from exuviae of known instars of the beet armyworm, spodoptera exigua (hübner) (lepidoptera: noctuidae), to determine the larval instars with the frequency distribution method and dyar's rule. head capsule widths of s. exigua ranged from 0.313 to 1.446 mm. ...201323786067
analyzing blends of herbivore-induced volatile organic compounds with factor analysis: revisiting "cotton plant, gossypium hirsutum l., defense in response to nitrogen fertilization".many herbivorous, predaceous, and parasitic insects use constitutive and herbivore-induced volatile organic compounds (vocs) to locate their respective host plant, prey, and hosts. multivariate statistical tools (e.g., factor analysis) are recognized increasingly as an appropriate approach for analyzing intercorrelated data such as presence/absence or quantities of vocs. one challenge of implementing factor analysis is determining how many new variables (factors) to retain in the final analysis. ...201323786100
transcriptome analysis and screening for potential target genes for rnai-mediated pest control of the beet armyworm, spodoptera exigua.the beet armyworm, spodoptera exigua (hübner), is a serious pest worldwide that causes significant losses in crops. unfortunately, genetic resources for the beet armyworm is extremely scarce. to improve these resources we sequenced the transcriptome of s. exigua representing all stages including eggs, 1(st) to 5(th) instar larvae, pupae, male and female adults using the illumina solexa platform. we assembled the transcriptome with trinity that yielded 31,414 contigs. of these contigs, 18,592 wer ...201323823756
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 ...201323827975
a spodoptera exigua cadherin serves as a putative receptor for bacillus thuringiensis cry1ca toxin and shows differential enhancement of cry1ca and cry1ac toxicity.crystal toxin cry1ca from bacillus thuringiensis has an insecticidal spectrum encompassing lepidopteran insects that are tolerant to current commercially used b. thuringiensis crops (bt crops) expressing cry1a toxins and may be useful as a potential bioinsecticide. the mode of action of cry1a is fairly well understood. however, whether cry1ca interacts with the same receptor proteins as cry1a remains unproven. in the present paper, we first cloned a cadherin-like gene, secad1b, from spodoptera e ...201323835184
corn defense responses to nitrogen availability and subsequent performance and feeding preferences of beet armyworm (lepidoptera: noctuidae).many studies have reported the effect of nitrogen (n) fertilization on plant constitutive defense responses; however, little is known about their effects on plant induced defense patterns and its consequence for insect herbivores. in our experiments, the effects of n availability on growth, nutritional quality (n content, protein/carbohydrate [p:c] ratio, modified gross energy [mge]), and constitutive phenolics of corn, zea mays l. were quantified. moreover, the indirect effects of n fertilizati ...201323865189
cloning, expression analysis, and molecular modeling of the gamma-aminobutyric acid receptor alpha2 subunit gene from the common cutworm, spodoptera litura.intensive research on the molecule structures of the gamma-nminobutyric acid (gaba) receptor in agricultural pests has great significance to the mechanism investigation, resistance prevention, and molecular design of novel pesticides. the gaba receptor a2 (slgabarα2) subunit gene in spodoptera litura (fabricius) (lepidoptera: noctuidae) was cloned using the technologies of reverse transcription pcr and rapid amplification of cdna ends. the gemonic dna sequence of slgabarα2 has 5164 bp with 8 exo ...023909412
rna interference of glycerol biosynthesis suppresses rapid cold hardening of the beet armyworm, spodoptera exigua.the beet armyworm, spodoptera exigua, is a freeze-susceptible species that overwinters in temperate zones without diapause. a rapid cold hardening (rch) and supercooling capacity usually play crucial roles in survival during the overwintering period. this study identified a cryoprotectant as a rch factor of s. exigua. pre-exposure of s. exigua larvae to 4°c significantly increased survival at -10°c in all developmental stages from egg to adult. rch was dependent on the duration of the pre-exposu ...201323948473
foliar persistence and residual activity of methoxyfenozide against beet armyworm (lepidoptera: noctuidae).a greenhouse study was conducted to investigate the persistence of methoxyfenozide in pepper (capsicum annuum l.) foliage. an aqueous suspension of methoxyfenozide was sprayed on pepper plants at concentrations of 72 and 144 mg of active ingredient (a.i.)/l. foliage was collected at different intervals of time (0, 3, 5, 10, 20, 30, 40, and 50 days) after the treatment, and the methoxyfenozide residue was measured by high-performance liquid chromatography. the foliage was also used in bioassays t ...201323956070
characterization of a β-1,3-glucan recognition protein from the beet armyworm, spodoptera exigua (insecta: lepidoptera: noctuidae).the β-1,3-glucan recognition protein gene from spodoptera exigua (seβgrp) was cloned and characterized. the cdna of this gene is 1 644 nucleotides in length and the predicted polypeptide is 491 amino acids (aa) in length, with a calculated molecular mass of 54.8 kda. the first 22 aa encode a predicted secretion signal peptide. a blast search, multiple sequence alignment, and phylogenetic analysis of the aa sequence of seβgrp revealed that this protein is most similar to the β-1,3-glucan recognit ...201323956146
expression of soybean lectin in transgenic tobacco results in enhanced resistance to pathogens and pests.lectins are proteins of non-immune origin that specifically interact with carbohydrates, known to play important roles in the defense system of plants. in this study, in order to study the function of a new soybean lectin (sbl), the corresponding encoding gene lec-s was introduced into tobacco plants via agrobacterium-mediated transformation. southern blot analyses had revealed that the lec-s gene was stable integrated into the chromosome of the tobacco. the results of the reverse transcription ...201323987807
lethal and sublethal effects of spinosad on spodoptera exigua (lepidoptera: noctuidae).as a selective biological insecticide, spinosad has been used widely for the control of pests including beet armyworm, spodoptera exigua (hübner) (lepidoptera: noctuidae). to form effective pest control strategies, lethal and sublethal effects should be considered for a complete analysis of spinosad impact. however, few studies have been reported to investigate sublethal effects of spinosad on s. exigua. this study attempts to evaluate the lethal and sublethal effects of spinosad on this pest by ...201324020299
insecticide resistance status of field populations of spodoptera exigua (lepidoptera: noctuidae) from china.beet armyworm, spodoptera exigua (hübner), is a serious pest of vegetables in china, and its control is heavily dependent on chemical insecticides. the current resistance status of nine insecticides was investigated in 16 field populations collected from seven provinces of china during 2009-2012. compared with the susceptible strain wh-s, some field populations evolved various levels of resistance to eight of the nine insecticides tested: emamectin benzoate (4- to 348-fold), indoxacarb (2- to 41 ...201324020303
rna interference of cadherin gene expression in spodoptera exigua reveals its significance as a specific bt target.cadherin is a calcium-dependent cell surface molecule and has been proposed to be a target molecule of bacillus thuringiensis cry proteins. based on a partial cadherin gene obtained from 454 pyrosequencing transcripts of the fifth instar spodoptera exigua midgut, a full open reading frame of cadherin gene (secad1) was cloned. its predicted amino acid sequence encodes extracellular 9 cadherin repeats, a transmembrane, and intracellular domain. secad1 gene was expressed in all developmental stages ...201324055650
isolation and characterization of burkholderia rinojensis sp. nov., a non-burkholderia cepacia complex soil bacterium with insecticidal and miticidal activities.isolate a396, a bacterium isolated from a japanese soil sample demonstrated strong insecticidal and miticidal activities in laboratory bioassays. the isolate was characterized through biochemical methods, fatty acid methyl ester (fame) analysis, sequencing of 16s rrna, multilocus sequence typing and analysis, and dna-dna hybridization. fame analysis matched a396 to burkholderia cenocepacia, but this result was not confirmed by 16s rrna or dna-dna hybridization. 16s rrna sequencing indicated clos ...201324096416
xaxab-like binary toxin from photorhabdus luminescens exhibits both insecticidal activity and cytotoxicity.the enterobacterium photorhabdus luminescens produces a number of toxins to kill its insect host. by analyzing the genomic sequence of p. luminescens tt01, we found that amino acid sequences encoded by plu1961 and plu1962 showed high similarity to xaxab binary toxin of xenorhabuds nematophila, which has both necrotic and apoptotic activities in both insect and mammalian cells in vitro. to evaluate the biological activity of plu1961/plu1962, their coding genes were cloned and expressed in escheri ...201424188660
exogenous jasmonates simulate insect wounding in tomato plants (lycopersicon esculentum) in the laboratory and field.wounding increases the levels and activities of several defense-related proteins in the foliage of the tomato plant,lycopersicon esculentum mill. evidence indicates that two of these responses, the systemic increases in polyphenol oxidase and proteinase inhibitors, are regulated by an octadecanoid-based signalling pathway which includes the wound hormone, jasmonic acid. it is not known whether other responses to wounding are also regulated by this same signalling pathway. in this paper, we show ...199624227107
an elicitor in caterpillar oral secretions that induces corn seedlings to emit chemical signals attractive to parasitic wasps.regurgitate of corn-fed beet armyworm (baw) caterpillars,spodoptera exigua, when applied to damaged sites of corn (zea mays) seedlings, causes the release of relatively large amounts of terpenes by the seedlings several hours later. this plant response could be induced by merely placing the cut stem of seedlings in a solution of baw regurgitate for 12 hr, a response that could not be induced by placing seedlings in water only. regurgitate of baw fed various diets, including a minimal diet of fil ...199324248945
quantification of insect growth and its use in screening of naturally occurring insect control agents.in studies of the effects of allelochemicals or other factors on the development of different insect species, comparison of growth-inhibiting activities is difficult using the parameters currently employed. we introduce two new parameters, growth index (gi) and relative growth index (rgi), which can unify the quantification of insect development. this quantification can also eliminate the effects of different growth characteristics due to the genetic differences between insect species. by measur ...199324249129
host recognition by entomopathogenic nematodes: behavioral response to contact with host feces.host recognition by entomopathogenic nematodes may occur through contact with insects' excretory products, cuticle, or gut contents. we analyzed the behavioral responses of four species of entomopathogenic nematodes during contact with feces of natural or experimental hosts. host recognition by nematodes was manifested in alterations in the frequency and/or duration of one or more search parameters including forward crawling, headwaving, body-waving, stopping, backward crawling, head-rubbing, an ...199324249139
selectively fluorinated analogs reveal differential olfactory reception and inactivation of green leaf volatiles in insects.the role of the alkyl terminus of green leaf volatile (glv) molecules in olfactory reception and inactivation was examined in three diverse insect species: the beet armyworm,spodoptera exigua (lepidoptera); the colorado potato beetle,leptinotarsa decemlineata (coleoptera); and the desert locust,schistocerca gregaria (orthoptera), using selectively fluorinated analogs of glvs and electroantennograms (eags). when only the magnitude of the depolarization of the eag is considered (a measure of recep ...199324249373
detrimental effects ofcinchona leaf alkaloids on larvae of the polyphagous insectspodoptera exigua.youngcinchona ledgeriana plants contain two types of alkaloid: indole alkaloids in the leaves and quinoline alkaloids in the root. fromcinchona leaves, a crude alkaloid extract was made, containing the cinchophylline type of indole alkaloids and a small amount of 5-methoxytryptamine. the leaf alkaloid extract exerted a strong detrimental effect on the growth of larvae of the polyphagous beet armyworm,spodoptera exigua (lepidoptera). feeding of larvae on an artificial diet containing the leaf alk ...199224254775
analysis and field evaluation of volatile blend emitted by calling virgin females of beet armyworm moth,spodoptera exigua (hübner).the volatile blend emitted by calling virgin beet armyworm females was collected and analyzed by capillary gas chromatography and mass spectrometry. five compounds were detected and identified in this blend: (z)-9-tetradecenyl acetate, (z)-9-tetradecen-l-ol, (z,e)-9,12-tetradecadienyl acetate (z,z)-9,12-tetradecadienyl acetate, and (z)-l 1-hexadecenyl acetate. they were emitted in a ratio of 47.9 ∶4.0∶40.2 ∶6.5 ∶ 1.7, respectively. this five-component blend and several other blends with one or m ...199024263438
the influence of dietaryβ-carboline alkaloids on growth rate, food consumption, and food utilization of larvae ofspodoptera exigua (hubner).β-carboline alkaloids are found worldwide in many plant families. harman, harmine, and other simple β-carboline alkaloids were tested for activity against a generalist phytophagous insect, the beet army worm [spodoptera exigua (hubner)]. chronic dietary exposure tests (neonate to pupa) reveal potent antifeedant and possible toxic effects. acute dietary exposure tests on fifth-instar larvae also demonstrate antifeedant activity.198824275994
a novel cry9aa with increased toxicity for spodoptera exigua (hübner).cry9aa, produced by bacillus thuringiensis is reported to be not active against spodoptera exigua (beet armyworm). in this study we have cloned a new cry9aa5 gene encoding a protoxin with increased activity against s. exigua as compared to cry9aa1. when aligned to cry9aa1, four amino acid substitutions in domain i and one substitution in the c-terminal protein extension of cry9aa5 were identified. toxicity of cry9aa5, produced in recombinant escherichia coli was assessed and compared to the acti ...201424286660
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