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distribution, frequency, and diversity of bacillus thuringiensis in an animal feed mill.bacillus thuringiensis was isolated from 36 of 50 residue samples obtained from an animal feed mill (a stored-product environment). of 710 selected colonies having bacillus cereus-b. thuringiensis morphology isolated from the samples, 477 were classified as b. thuringiensis because of production of parasporal delta-endotoxin crystals. there was a diverse population of b. thuringiensis, as revealed by differentiation of the isolates into 36 subgroups by using (i) their spectra of toxicity to the ...199216348699
changes in permeability of brush border membrane vesicles from spodoptera littoralis midgut induced by insecticidal crystal proteins from bacillus thuringiensis.bacillus thuringiensis insecticidal crystal proteins (icps) are thought to induce pore formation in midgut cell membranes of susceptible insects. cry1ca, which is significantly active in spodoptera littoralis, made brush border membrane vesicles permeable to kcl (osmotic swelling was monitored by the light scattering technique); the marginally active icps cry1aa, cry1ab, and cry1ac did not.199816349555
development and predation of picromerus bidens (heteroptera: pentatomidae) on spodoptera littoralis (lepidoptera: noctuidae) at different constant temperatures. 200516366301
effects of feeding spodoptera littoralis on lima bean leaves. iii. membrane depolarization and involvement of hydrogen peroxide.in response to herbivore (spodoptera littoralis) attack, lima bean (phaseolus lunatus) leaves produced hydrogen peroxide (h(2)o(2)) in concentrations that were higher when compared to mechanically damaged (md) leaves. cellular and subcellular localization analyses revealed that h(2)o(2) was mainly localized in md and herbivore-wounded (hw) zones and spread throughout the veins and tissues. preferentially, h(2)o(2) was found in cell walls of spongy and mesophyll cells facing intercellular spaces, ...200616443697
structural relationships, distribution and biological activities of stemona alkaloids.stemona alkaloids represent a unique class of natural products exclusively isolated from the monocotyledonous family stemonaceae comprising three genera mainly distributed in southeast asia. structurally the alkaloids are characterised by a pyrrolo[1,2- a]azepine nucleus usually linked with two carbon chains mostly forming terminal lactone rings. based on biosynthetic considerations and their various distribution the present review describes 82 stemona alkaloids grouped into three skeletal types ...200616491444
the phytopathogen dickeya dadantii (erwinia chrysanthemi 3937) is a pathogen of the pea aphid.dickeya dadantii (erwinia chrysanthemi) is a phytopathogenic bacterium causing soft rot diseases on many crops. the sequencing of its genome identified four genes encoding homologues of the cyt family of insecticidal toxins from bacillus thuringiensis, which are not present in the close relative pectobacterium carotovorum subsp. atrosepticum. the pathogenicity of d. dadantii was tested on the pea aphid acyrthosiphon pisum, and the bacterium was shown to be highly virulent for this insect, either ...200616517643
potato expressing beetle-specific bacillus thuringiensis cry3aa toxin reduces performance of a moth.expression of the bacillus thuringiensis beetle-specific toxin cry3aa, which renders a genetically modified potato cultivar resistant to the colorado potato beetle leptinotarsa decemlineata, exerts a deleterious effect on the polyphagous moth spodoptera littoralis. the caterpillars of s. littoralis feed less and produce smaller pupae on the genetically modified cultivar (newleaf superior) than on the parental nontransgenic cultivar (superior). the conversion efficiencies of total dry matter, com ...200616525866
insect-antifeedant and antibacterial activity of diterpenoids from species of plectranthus.bio-assay guided fractionation of an acetone extract of leaf material from plectranthus saccatus benth. resulted in the isolation of a beyerane diterpenoid. this compound, characterised by spectroscopic methods as ent-3beta-(3-methyl-2-butenoyl)oxy-15-beyeren-19-oic acid, showed insect antifeedant activity against spodoptera littoralis. known quinonoid abietane diterpenoids obtained from new sources included a mixture of the (4r,19r) and (4r,19s) diastereoisomers of coleon a from p. aff. puberul ...200616631828
dof transcription factor atdof1.1 (obp2) is part of a regulatory network controlling glucosinolate biosynthesis in arabidopsis.glucosinolates are a group of secondary metabolites that function as defense substances against herbivores and micro-organisms in the plant order capparales. indole glucosinolates (igs), derivatives of tryptophan, may also influence plant growth and development. in arabidopsis thaliana, indole-3-acetaldoxime (iaox) produced from tryptophan by the activity of two cytochrome p450 enzymes, cyp79b2 and cyp79b3, serves as a precursor for igs biosynthesis but is also an intermediate in the biosyntheti ...200616740150
spider venom toxin protects plants from insect attack.many of the toxin proteins, that have been heterogeneously expressed in agricultural crops to provide resistance to insect pests, are too specific or are only mildly effective against the major insect pests. spider venoms are a complex cocktail of toxins that have evolved specifically to kill insects. here we show that the omega-actx-hv1a toxin (hvt), a component of the venom of the australian funnel web spider (hadronyche versuta) that is a calcium channel antagonist, retains its biological act ...200616779650
alkaline protease associated with virus particles of a nuclear polyhedrosis virus: assay, purification, and properties.proteolytic activity was detected within polyhedra of the nuclear polyhedrosis virus of spodoptera littoralis. the enzyme activity was detected by its ability to degrade the major structural polypeptide of polyhedra (polyhedrin). a quantitative assessment of activity was made by a radioassay technique using (3)h-labeled polyhedrin as the substrate. of the structural components of polyhedra, virus particles showed the greatest specific proteolytic activity. preparations of purified nucleocapsids ...197816789169
response of immunocompetent and immunosuppressed spodoptera littoralis larvae to baculovirus infection.the mediterranean lepidopteran pest spodoptera littoralis is highly resistant to infection with the autographa californica multiple nucleopolyhedrovirus (acmnpv) via the oral route, but highly sensitive to infection with budded virus (bv) via the intrahaemocoelic route. to study the fate of acmnpv infection in s. littoralis, vhsgfp, an acmnpv recombinant that expresses the reporter green fluorescent protein gene under the control of the drosophila heat-shock promoter, and high-resolution fluores ...200616847117
enhancement of fungicidal and insecticidal activity by reductive alkylation of chitosan.a series of n-alkyl chitosan (nac) derivatives were synthesized using a reductive alkylation reaction to examine their fungicidal and insecticidal activity. the chemical structures were characterized by ir and (1)h nmr spectroscopy, and the degree of substitution (ds) ranged from 0.02 to 0.37. their fungicidal activity was evaluated against the grey mould botrytis cinerea pers ex fr (leotiales: sclerotiniaceae) and the rice leaf blast pathogen pyricularia grisea sacc [teleomorph: magnaporthe gri ...200616847817
biosynthesis of 10,12-dienoic fatty acids by a bifunctional delta11 desaturase in spodoptera littoralis.in the biosynthetic pathway of spodoptera littoralis sex pheromone, (e,e)-10,12-tetradecadienoic acid is produced from (z)-11-tetradecenoic acid by desaturation and concomitant migration of the precursor double bond. with the aim of identifying the enzyme involved in this biotransformation, yeast deltaelo1/deltaole mutants, which are both elongase 1 and delta9 desaturase-deficient, were transformed with the s. littoralis delta11 desaturase gene using a cu+2 inducible expression vector. the trans ...200616876706
characterization in relation to development of an ecdysteroid agonist-responsive cytochrome p450, cyp18a1, in lepidoptera.cytochrome p450 enzymes are involved in a number of steps in ecdysteroid (moulting hormone) homeostasis in insects. we report the cloning and characterization of an ecdysteroid agonist-responsive cytochrome p450, cyp18a1, from the cotton leafworm, spodoptera littoralis. northern blot analysis showed that the mrna transcript was expressed at times of increasing ecdysteroid titre in final instar s. littoralis larvae and was induced by the ecdysteroid receptor agonist, rh-5992, in midgut and fat bo ...200616884680
a novel function for the cathepsin d inhibitor in tomato.proteinaceous aspartic proteinase inhibitors are rare in nature and are described in only a few plant species. one of them corresponds to a family of cathepsin d inhibitors (cdis) described in potato (solanum tuberosum), involving up to 15 isoforms with a high sequence similarity. in this work, we describe a tomato (solanum lycopersicum) wound-inducible protein called jasmonic-induced protein 21 (jip21). sequence analysis of its cdna predicted a putative function as a cdi. the jip21 gene, whose ...200617012408
pleiotropic role of quorum-sensing autoinducer 2 in photorhabdus luminescens.bacterial virulence is an integrative process that may involve quorum sensing. in this work, we compared by global expression profiling the wild-type entomopathogenic photorhabdus luminescens subsp. laumondii tt01 to a luxs-deficient mutant unable to synthesize the type 2 quorum-sensing inducer ai-2. ai-2 was shown to regulate more than 300 targets involved in most compartments and metabolic pathways of the cell. ai-2 is located high in the hierarchy, as it controls the expression of several tra ...200617021191
expression and down-regulation of cytochrome p450 genes of the cyp4 family by ecdysteroid agonists in spodoptera littoralis and drosophila melanogaster.the function of cyp4 genes in insects is poorly understood. some cyp genes are up-regulated by ecdysteroids and a number of cyp4 genes in drosophila melanogaster have been shown by microarray to be down-regulated when the ecdysteroid titre is high, suggesting hormonal regulation. here, we report the utilization of certain cloned cyp4 cdnas/fragments to probe their developmental/tissue expression in the lepidopteran, spodoptera littoralis, including the effects of ecdysteroid receptor agonists (b ...200617027846
delta11 desaturases of trichoplusia ni and spodoptera littoralis exhibit dual catalytic behaviour.the delta(11) desaturases found in moths such as spodoptera littoralis play a critical role in the biosynthesis of their sex pheromones. the ability to functionally express these enzymes in yeast has allowed one to study the transformation of long-chain fatty acyl substrates to their 11-ene products in greater mechanistic detail. in this article, we report on the detection and quantitation of a minor 11-hydroxylated byproduct (0.1% of total fatty acids), which is formed by the delta(11) desatura ...200617027848
altered glucosinolate hydrolysis in genetically engineered arabidopsis thaliana and its influence on the larval development of spodoptera littoralis.the antiherbivore potential of the glucosinolate-myrosinase defense system found in plants of the order capparales is heavily influenced by the types of hydrolysis products (e.g. isothiocyanates, nitriles) formed from the parent glucosinolates upon plant damage. however, comparison of the effects of glucosinolate hydrolysis products on insect herbivores has been hampered by the lack of suitable experimental tools for rigorous bioassays, such as intact plants differing only in the types of hydrol ...200617061170
effects of potato plants expressing a barley cystatin on the predatory bug podisus maculiventris via herbivorous prey feeding on the plant.the aim of this study was to assess the effects of potato plants expressing a barley cystatin on a potentially cystatin-susceptible natural enemy by predation on susceptible and non-susceptible preys feeding on the plant. we have focussed on the impact of the variant hvcpi-1 c68 --> g, in which the only cysteine residue was changed by a glycine, on the growth and digestive physiology of the colorado potato beetle (cpb), leptinotarsa decemlineata, and the egyptian cotton leafworm (ecw), spodopter ...200717072562
effects of temperature on predation by the stinkbugs picromerus bidens and podisus maculiventris (heteroptera: pentatomidae) on noctuid caterpillars.environmental risks associated with the use of non-indigenous organisms for augmentative biological control have received growing attention. in europe, the native pentatomid predator picromerus bidens (linnaeus) has been considered a potential alternative to the north american pentatomid podisus maculiventris (say) for the control of lepidopteran, coleopteran and hymenopteran defoliator pests. in the current study, prey consumption and developmental duration of the predatory stages of p. bidens ...200617092360
antifeedant c20 diterpene alkaloids.we have tested the insect antifeedant and toxic activity of 21 c20 diterpenoid alkaloids on spodoptera littoralis and leptinotarsa decemlineata. the antifeedant effects of the test compounds were structure- and species-dependent. the most active antifeedants to l. decemlineata and s. littoralis were the rearranged form of hetisine (20; ec50 = 1.7 microg/cm2) and 19-oxodihydroatisine (9; ec50 = 0.1 microg/cm2), resp. glandulosine (8) moderately affected orally injected s. littoralis larvae. a few ...200417191910
growth and mitogenic effects of arylphorin in vivo and in vitro.in insects, developmental responses are organ- and tissue-specific. in previous studies of insect midgut cells in primary tissue cultures, growth-promoting and differentiation factors were identified from the growth media, hemolymph, and fat body. recently, it was determined that the mitogenic effect of a manduca sexta fat body extract on midgut stem cells of heliothis virescens was due to the presence of monomeric alpha-arylphorin. here we report that in primary midgut cell cultures, this same ...200717212351
ectopically expressed leaf and bulb lectins from garlic (allium sativum l.) protect transgenic tobacco plants against cotton leafworm (spodoptera littoralis).the insecticidal activity of the leaf (asal) and bulb (asaii) agglutinins from allium sativum l. (garlic) against the cotton leafworm, spodoptera littoralis boisd. (lepidoptera: noctuidae) was studied using transgenic tobacco plants expressing the lectins under the control of the constitutive camv35s promoter. pcr analysis confirmed that the garlic lectin genes were integrated into the plant genome. western blots and semi-quantitative agglutination assays revealed lectin expression at various le ...200817265166
ca2+ stabilizes the membrane potential of moth olfactory receptor neurons at rest and is essential for their fast repolarization.the role of ca(2+) in insect olfactory transduction was studied in the moth spodoptera littoralis. single sensillum recordings were made to investigate in vivo the role of sensillar ca(2+) on the electrophysiological properties of sex pheromone responsive olfactory receptor neurons (orns). lowering the sensillar ca(2+) concentration to 2 x 10(-8) m increased orn spontaneous firing activity and induced long bursts of action potentials (aps) superimposed on spontaneous negative deflections of the ...200717267420
molecular cloning and characterization of bombyx mori sterol carrier protein x/sterol carrier protein 2 (scpx/scp2) gene.cholesterol transport is a very important process in insect. we have isolated the bombyx mori sterol carrier protein x (bmscpx) cdna and sterol carrier protein 2 (bmscp2) cdna: a 1.7 kb clone encoding scpx, a 3-ketoacyl coa thiolase, and 0.6 kb clone presumably encoding scp2, which is thought to be an intracellular lipid transfer protein. interestingly, the identical gene scpx/scp2 encodes the two types of transcripts by alternative splicing mechanism in bombyx mori. the scpx mrna spans two exon ...200617343205
cloning and characterization of the pheromone biosynthesis activating neuropeptide receptor gene in spodoptera littoralis larvae.in noctuid moths cuticular pigmentation is regulated by the pyrokinin/pheromone biosynthesis activating neuropeptide (pk/pban) family, which also mediates a variety of other functions in moths and other insects. numerous studies have shown that these neuropeptides exert their functions through activation of the pban receptor (pban-r), with subsequent ca(2+) influx, followed by either activation of camp or direct activation of downstream kinases. recently, several pban-rs have been identified, al ...200717379458
efficacy of some plant oils alone and/or combined with different insecticides on the cotton leaf-worm spodoptera littoralis (boisd.) (lepidoptera: noctuidae) in egypt.the present work was conducted to evaluate the efficiency of two essential oils ((flax or "linseed" and sesame ), five volatile plant oils ( camphor, red basil, rose, menthol and clove ), four pesticides (methoxyfenozide; permethrin; profenofos and spinosad) and their mixtures on the cotton leaf-worm spodoptera littoralis (boisd.). this study was also devoted to minimize the usage of conventional insecticides, reduce the environmental pollution, and protect human-beings and domestic animals from ...200617385497
diversity in pathogenicity of steinernema carpocapsae and its symbiotic bacterium for spodoptera spp.pathogenicity of five isolates of steinernema carpocapsae (ger: germany, buw: becker underwood, kop: koppert, cz: czech republic, bel: belgium) were tested against the fourth instar larvae of the cotton leaf worm, spodoptera littoralis and the beet armyworm, spodoptera exigua (lepidoptera: noctuidae) at different concentrations (0, 5, 10, 25, and 50 infective juveniles/cm2) in petri dishes (9 cm dia.) lined with filter paper. results obtained after 48 h exposure indicated that the pathogenicity ...200617390810
effect of exogenous ecdysteroids on growth, development, and fertility of the egyptian cotton leafworm spodoptera littoralis boisd. (lepidoptera: noctuidae). 201617425056
impact of a turkish isolate and a plaque-purified variant of splinpv-b on larval stage development of spodoptera littoralis (lepidoptera: noctuidae) boisd.baculoviruses can alter the development and physiological status of their insect hosts. in the present study, two spodoptera littoralis nucleopolyhedroviruses (splinpv-tr1 and splinpv-m2) were examined in terms of their effect on the stage development of s. littoralis at two doses/concentrations by inoculation of neonates or third instars. both isolates had an acute pathological effect on neonates. however, larval development was prolonged (6-36 h) by either infection when neonates were infected ...200717437256
a new steroid glycoside and furochromones from cyperus rotundus l.further phytochemical investigation of the aerial parts of cyperus rotundus l. afforded a new steroid glycoside named sitosteryl (6'-hentriacontanoyl)-beta-d-galactopyranoside (4) in addition to three furochromones, khellin (2), visnagin (3) and ammiol (9). furthermore, benzo-alpha-pyrone (coumarin) (1), salicylic acid (5), caffeic acid (6), protocatechuic acid (7), p-coumaric acid (8), tricin (10) and isorhamnetin (11) were isolated. the structures of these compounds were established by spectro ...200717479423
a potato carboxypeptidase inhibitor gene provides pathogen resistance in transgenic rice.a defensive role against insect attack has been traditionally attributed to plant protease inhibitors. here, evidence is described of the potential of a plant protease inhibitor, the potato carboxypeptidase inhibitor (pci), to provide resistance to fungal pathogens when expressed in rice as a heterologous protein. it is shown that rice plants constitutively expressing the pci gene exhibit resistance against the economically important pathogens magnaporthe oryzae and fusarium verticillioides. a m ...200717547659
biosafety of recombinant and wild type nucleopolyhedroviruses as bioinsecticides.the entomopathogenic autographa californica (speyer) nucleopolyhedrovirus (acmnpv) has been genetically modified to increase its speed of kill. the potential adverse effects of a recombinant acmnpv (acaait) as well as wild type acmnpv and wild type spodoptera littoralis npv (slnpv) were studied. cotton plants were treated with these viruses at concentrations that were adjusted to resemble the recommended field application rate (4 x 10(12) pibs/feddan, feddan = 4,200 m2) and 3rd instar larvae of ...200717617674
larvicidal activities against agricultural pests of transgenic escherichia coli expressing combinations of four genes from bacillus thuringiensis.the genes cry1ac and cry1ca from bacillus thuringiensis subsps. kurstaki hd-73 and aizawai 4j4, respectively, encoding delta-endotoxins against lepidopteran larvae were isolated, cloned and expressed in escherichia coli, with and without cyt1aa (encoding cytolytic protein) and p20 (accessory protein) from subsp. israelensis. nine combinations of the genes under control of an early t7, p a1 inducible promoter, produced the encoding proteins. toxicities were examined against larvae of three major ...200717665174
transcriptional analysis of polydnaviral genes in the course of parasitization reveals segment-specific patterns.polydnaviruses are symbiotic viruses of endoparasitic wasps, which are formed in their ovary and injected along with the eggs into the host. they manipulate the host in a way to allow successful parasitoid development. a hallmark of polydnaviruses is their segmented genome consisting of several circles of double-stranded dna. we are studying the solitary egg-larval parasitoid chelonus inanitus (braconidae) parasitizing spodoptera littoralis (noctuidae). the polydnavirus of chelonus inanitus (civ ...200717694561
simultaneous feeding by aboveground and belowground herbivores attenuates plant-mediated attraction of their respective natural enemies.herbivore-damaged plants emit volatile organic compounds that attract natural enemies of the herbivores. this form of indirect plant defence occurs aboveground as well as belowground, but it remains unclear how simultaneous feeding by different herbivores attacking leaves and roots may affect the production of the respective defence signals. we employed a setup that combines trapping of volatile organic signals and simultaneous measurements of the attractiveness of these signals to above and bel ...200717845293
signaling pathways controlling induced resistance to insect herbivores in arabidopsis.insect attack triggers changes in transcript level in plants that are mediated predominantly by jasmonic acid (ja). the implication of ethylene (et), salicylic acid (sa), and other signals in this response is less understood and was monitored with a microarray containing insect- and defense-regulated genes. arabidopsis thaliana mutants coi1-1, ein2-1, and sid2-1 impaired in ja, et, and sa signaling pathways were challenged with the specialist small cabbage white (pieris rapae) and the generalist ...200717977152
bioactive polychlorinated bibenzyls from the liverwort riccardia polyclada.gc-ms and (1)h nmr spectroscopic profiling of a cdcl 3 extract of the liverwort riccardia polyclada (syn. r. umbrosa) revealed the presence of four main compounds bearing several chlorine atoms on a bibenzyl skeleton. separation of a ch 2cl 2 extract was achieved using preparative tlc, and structures 1- 4 were proposed on the basis of spectroscopic evidence. compounds 1- 4 were active in a brine shrimp lethality bioassay ( artemia salina). in addition, 2 and 4 displayed moderate antifeedant acti ...200718020419
bioactivity of two major constituents isolated from the essential oil of artemisia judaica l.the essential oil of artemisia judaica l., grown on sinai peninsula of egypt, was extracted via hydrodistillation. chromatographic separation on repeated silica gel columns led to isolate two compounds namely piperitone and trans-ethyl cinnamate. insecticidal, antifeedant and antifungal properties of the isolated compounds were examined. both compounds showed pronounced insecticidal and antifeedant activity against the third instar larvae of spodoptera littoralis (boisd). trans-ethyl cinnamate ( ...200818054484
the hcar regulatory protein of photorhabdus luminescens affects the production of proteins involved in oxidative stress and toxemia.comparison of the proteomes of wild-type photorhabdus luminescens and its hcar derivative, grown in insect hemolymph, showed that hcar disruption decreased the production of toxins (tcda1, mcf, and pirab) and proteins involved in oxidative stress response (soda, ahpc, gor). the disruption of hcar did not affect growth rate in insects, but did delay the virulence of p. luminescens in bombyx mori and spodoptera littoralis larvae. this delayed virulence was associated with a lower toxemia rather th ...200718072208
effects of feeding spodoptera littoralis on lima bean leaves: iv. diurnal and nocturnal damage differentially initiate plant volatile emission.continuous mechanical damage initiates the rhythmic emission of volatiles in lima bean (phaseolus lunatus) leaves; the emission resembles that induced by herbivore damage. the effect of diurnal versus nocturnal damage on the initiation of plant defense responses was investigated using mecworm, a robotic device designed to reproduce tissue damage caused by herbivore attack. lima bean leaves that were damaged by mecworm during the photophase emitted maximal levels of beta-ocimene and (z)-3-hexenyl ...200818165324
angiotensin-converting enzyme in spodoptera littoralis: molecular characterization, expression and activity profile during development.the characterization of the full-length angiotensin-converting enzyme (ace) cdna sequence of the lepidopteran spodoptera littoralis is reported in this study. the predicted open reading frame encodes a 647 amino acids long protein (slace) and shows 63.6% identity with the bombyx mori ace sequence. a 3d-model, consisting of 26 alpha-helices and three beta-sheets, was predicted for the sequence. slace expression was studied in the embryonic, larval and pupal stages of s. littoralis and in differen ...200818207078
characterization of an egyptian spodoptera littoralis nucleopolyhedrovirus and a possible use of a highly conserved region from polyhedrin gene for nucleopolyhedrovirus detection.an egyptian isolate of spodoptera littoralis nucleopolyhedrovirus (splinpv) was tested for its potential as biocontrol agent in comparison to autographa californica multiple nucleopolyhedrovirus (acmnpv). comparative assays of splinpv and acmnpv against 2nd instar larvae of spodoptera littoralis revealed 4-fold greater susceptibility of s. littoralis to acmnpv than to splinpv based on lc50 values for the two viruses. the lt50s determined for splinpv and acmnpv using lc50 of the virus against 2nd ...200818215282
compatibility of endoparasitoid hyposoter didymator (hymenoptera: ichneumonidae) protected stages with five selected insecticides.hyposoter didymator (thunberg) (hymenoptera: ichneumonidae) is a koinobiont endoparasitoid that emerges from the parasitization of economically important noctuid pests. h. didymator also is considered one of the most important native biocontrol agents of noctuids in spain. side effects of five insecticides with very different modes of action (fipronil, imidacloprid, natural pyrethrins + piperonyl butoxide, pymetrozine, and triflumuron) at the maximum field recommended rate in spain were evaluate ...200718232395
a maize (e)-beta-caryophyllene synthase implicated in indirect defense responses against herbivores is not expressed in most american maize varieties.the sesquiterpene (e)-beta-caryophyllene is emitted by maize (zea mays) leaves in response to attack by lepidopteran larvae like spodoptera littoralis and released from roots after damage by larvae of the coleopteran diabrotica virgifera virgifera. we identified a maize terpene synthase, terpene synthase 23 (tps23), that produces (e)-beta-caryophyllene from farnesyl diphosphate. the expression of tps23 is controlled at the transcript level and induced independently by d. v. virgifera damage in r ...200818296628
bioactive triterpene derivatives from latex of two euphorbia species.we have investigated the antifeedant and toxic effects of 23 semisynthetic terpenoid derivatives obtained through chemical modifications of the major components of euphorbia resinifera (alpha-euphol and alpha-euphorbol) and e. officinarum (obtusifoliol and 31-norlanostenol) latex on several insect species (spodoptera littoralis, myzus persicae and rhopalosiphum padi), their selective cytotoxicity on insect sf9 and mammalian cho cells and their phytotoxic effects on lactuca sativa. the conversion ...200818304594
antifeeding properties of myosuppressin in a generalist phytophagous leafworm, spodoptera littoralis (boisduval).insect myosuppressins are a family of peptides with a characteristic hv/sflrfamide carboxy terminus. they are expressed in brain, neurohemal organs, stomatogastric nervous system, and in midgut endocrine cells. from a functional point of view, myosuppressins inhibit contractions of different visceral muscles, stimulate certain skeletal muscles and activate enzyme secretion from the gut. moreover, in the omnivorous cockroach blattella germanica, myosuppressin inhibits food intake. based on these ...200818374428
increased terpenoid accumulation in cotton (gossypium hirsutum) foliage is a general wound response.the subepidermal pigment glands of cotton accumulate a variety of terpenoid products, including monoterpenes, sesquiterpenes, and terpenoid aldehydes that can act as feeding deterrents against a number of insect herbivore species. we compared the effect of herbivory by spodoptera littoralis caterpillars, mechanical damage by a fabric pattern wheel, and the application of jasmonic acid on levels of the major representatives of the three structural classes of terpenoids in the leaf foliage of 4-we ...200818386096
joint action of quercetin with four insecticides on the cotton leaf-worm larvae, spodoptera littoralis boisd. (lep. : noctuidae) in egypt.the naturally occurring phytoncidal chemical component of some plant- species are responsible for controlling and/or repelling insects from host plants. the use of natural products, readily available in the environment, to control the cotton leafworm, could be of help in reducing the need for applying the synthetic conventional insecticides . moreover, crude vegetable oils application is quite safer to the non targets and the environment. the use of sex attractant pheromones as predicative tools ...200718399473
biological performance of quercetin on the cotton leaf-worm larvae, spodoptera littoralis boisd. (lep., noctuidae) and prevailing natural enemies in the egyptian cotton fields.the egyptian cotton (gossypium barbadense l.) accounts for 65 % of the world production of long stable cultivars. taking into consideration the competition of other cotton producing countries, it should be of great importance to control pests, which attack the cotton plants to improve the yield and its quality. the main objective of this study is to develop new approaches for the management of the cotton leafworm spodoptera littoralis boisd. within an ipm program, that include synthetic insectic ...200718399494
first results on the insecticidal action of saponins.in the search for new, natural insecticides, numerous scientists are currently trying to obtain useful compound from plants. a possibly interesting class of molecules are the saponins, a group of steroidal or triterpenoidal secondary plant metabolites with divergent biological activities. in this study, we investigated the activity of saponins against living caterpillars spodoptera littoralis) and aphids (acyrthosiphon pisum) via treatment on artificial diets containing different concentrations ...200718399498
global and local modulatory supply to the mushroom bodies of the moth spodoptera littoralis.the moth spodoptera littoralis, is a major pest of agriculture whose olfactory system is tuned to odorants emitted by host plants and conspecifics. as in other insects, the paired mushroom bodies are thought to play pivotal roles in behaviors that are elicited by contextual and multisensory signals, amongst which those of specific odors dominate. compared with species that have elaborate behavioral repertoires, such as the honey bee apis mellifera or the cockroach periplaneta americana, the mush ...200818406668
predicted versus expressed adipokinetic hormones, and other small peptides from the corpus cardiacum-corpus allatum: a case study with beetles and moths.this mass spectrometric study confines itself to peptide masses in the range of 500-1500da. adipokinetic hormones (akhs) that are predicted from the genome of the red flour beetle, tribolium castaneum, and the silk moth, bombyx mori, are shown to exist as expressed peptides in the corpora cardiaca (cc) of the respective species as evidenced by various mass spectrometric methods. additionally, some related species were included in this study, such as the tenebrionid beetles tribolium brevicornis ...200818448200
antifeedant activity of some polygodial derivatives.polygodial (1) and its derivatives acetal 2 (propylene) and 3 (ethylene) were prepared and their antifeedant activity and toxic effects evaluated on several insect species with different feeding ecologies (spodoptera littoralis, leptinotarsa decemlineata, myzus persicae and rhopalosiphum padi) along with that of polygonone (4). we also tested their selective cytotoxic effects on insect-derived (spodoptera frugiperda ovarian sf9 cells) and mammalian chinese hamster ovary (cho) cells. the antifeed ...200818533465
induction of a nonoccluded baculovirus persistently infecting heliothis zea cells by heliothis armigera and trichoplusia ni nuclear polyhedrosis viruses.a nonoccluded singly enveloped baculovirus (baculovirus x) persistently infects heliothis zea (imc-hz-1) cells in culture. singly enveloped nuclear polyhedrosis viruses from h. zea and heliothis armigera, and multiply enveloped nuclear polyhedrosis viruses from trichoplusia ni, spodoptera frugiperda, and spodoptera littoralis were all found to induce baculovirus x. experiments are reported which use metabolic inhibitors and inactivated inducing virus to show that it is probable that a structural ...198118635066
dna restriction-pattern differences from geographic isolates of spodoptera littoralis nuclear polyhedrosis virus.two nuclear polyhedrosis viruses were isolated from spodoptera littoralis larvae collected from several areas in israel. the two viruses were characterized and compared by restriction endonuclease cleavage of their dna and southern blot hybridization. the two viruses have no detectable sequence homology. a variant, homologous to the more common virus isolate, was also found.198218635146
hahb4, a sunflower hd-zip protein, integrates signals from the jasmonic acid and ethylene pathways during wounding and biotic stress responses.the helianthus annuus (sunflower) hahb4 transcription factor belongs to the hd-zip family and its transcript levels are strongly induced when sunflower plants are attacked by herbivores, mechanically damaged or treated with methyl-jasmonic acid (meja) or ethylene (et). promoter fusion analysis, in arabidopsis and in sunflower, demonstrated that induction of hahb4 expression by these treatments is regulated at the transcriptional level. in transiently transformed sunflower plants hahb4 expression ...200818643970
independently silencing two photosynthetic proteins in nicotiana attenuata has different effects on herbivore resistance.insect attack frequently down-regulates photosynthetic proteins. to understand how this influences the plant-insect interaction, we transformed nicotiana attenuata to independently silence ribulose-1,5-bisphosphate carboxylase/oxygenase (rubpcase) activase (rca) and rubpcase and selected lines whose photosynthetic capacity was similarly reduced. decreases in plant growth mirrored the decreases in photosynthesis, but the effects on herbivore performance differed. both generalist (spodoptera litto ...200818723666
in vitro and in vivo effects of myo-active peptides on larvae of the tomato moth lacanobia oleracea and the cotton leaf worm spodoptera littoralis (lepidoptera; noctuidae).neuropeptides from five different neuropeptide families [manduca sexta allatostatin (manse-as), and manse-as deletion analogue(5-15), m. sexta allatotropin (manse-at), leucomyosuppressin, perisulfakinin, and myoinhibitory peptide i (mip i)] were assayed for their ability to affect the development and food consumption of penultimate and last larval instars of two lepidopteran species, l. oleracea and s. littoralis. injections of manse-as deletion analogue(5-15), manse-at, perisulfakinin, and mip ...200818780345
molecular identification and characterization of two new lepidoptera chemoreceptors belonging to the drosophila melanogaster or83b family.in insect antennae, olfaction depends on olfactory receptors (ors) that function through heterodimerization with an unusually highly conserved partner orthologue to the drosophila melanogaster dor83b. here, we report the identification of two cdnas encoding new dor83b orthologues that represent the first members, although nonconventional, of the or families of two noctuid crop pests, the cotton leafworm spodoptera littoralis and the cabbage armyworm mamestra brassicae. they both displayed high p ...200818828844
the effect of vibrio alginolyticus infection on caspase-3 expression and activity in white shrimp litopenaeus vannamei.complementary (c)dna encoding cysteine aspartate protease-3 (caspase-3) messenger (m)rna of the white shrimp litopenaeus vannamei was obtained from haemocytes by a reverse-transcription polymerase chain reaction (rt-pcr) and rapid amplification of cdna ends (race) using oligonucleotide primers based on the caspase sequences of penaeus merguiensis, spodoptera frugiperda, spodoptera littoralis, and penaeus monodon. the 1212-bp cdna contained an open reading frame (orf) of 951bp, a 56-bp 5'-untrans ...200818840531
plant enemy-derived elicitors increase the foliar tannin concentration of onobrychis viciifolia without a trade-off to growth.molecular experiments suggest that the regulation of the biosynthesis of condensed tannin (ct) is sensitive to the presence of plant enemies. the enemy-specific response of ct concentrations to simulated attacks by pathogenic fungi, bacteria or herbivores was studied in onobrychis viciifolia grown at four levels of nutrient availability. it was hypothesized that ct concentrations increase in response to an attack, and that constitutive and induced levels of ct are higher at low than at high nutr ...200818845664
an amphiphilic, pk/pban analog is a selective pheromonotropic antagonist that penetrates the cuticle of a heliothine insect.a linear pyrokinin (pk)/pheromone biosynthesis activating neuropeptide (pban) antagonist lead (ryf[df]prla) was structurally modified to impart amphiphilic properties to enhance its ability to transmigrate the hydrophobic cuticle of noctuid moth species and yet retain aqueous solubility in the hemolymph to reach target pk/pban receptors within the internal insect environment. the resulting novel pk/pban analog, hex-suc-a[df]prla (ppk-aa), was synthesized and evaluated as an antagonist in a phero ...200918992778
3-o-acetyl-narcissidine, a bioactive alkaloid from hippeastrum puniceum lam. (amaryllidaceae).in the context of the study on plant defensive compounds we have isolated the main alkaloid from hippeastrum puniceum (amaryllidaceae), 3-o-acetyl-narcissidine (1), and its biological activities tested against two divergent insect species and several plant species. 1 was isolated from the bioactive alkaloidal fraction of h. puniceum. its chemical structure was established by spectroscopic analysis. the biological activity tests showed that 1 is an antifeedant against the polyphagous insect spodo ...200819040099
bt maize fed-prey mediated effect on fitness and digestive physiology of the ground predator poecilus cupreus l. (coleoptera: carabidae).we investigated the effects of a bt maize hybrid on fitness and digestive physiology of the ground-dwelling predator poecilus cupreus l., as compared with the near-isogenic hybrid. a tritrophic assay revealed that there was a great decline in the detection of cry1ab toxin through the trophic chain, the concentration of the toxin being 945, 349 and 37 ng g(-1) of fresh weight in bt maize leaves, spodoptera littoralis (boisduval) larvae and p. cupreus larvae, respectively. moreover, the toxin was ...200919041318
screening spanish isolates of steinernematid nematodes for use as biological control agents through laboratory and greenhouse microcosm studies.entomopathogenic nematodes (epns) are one of the best non-chemical alternatives for insect pest control, with native epn strains that are adapted to local conditions considered to be ideal candidates for regional biological control programs. virulence screening of 17 native mediterranean epn strains was performed to select the most promising strain for regional insect pest control. steinernema feltiae (filipjev) (rhabditida: steinernematidae) rioja strain produced 7%, 91% and 33% larval mortalit ...200919073191
antifeedant and toxic activity of some plant extracts against larvae of cotton leafworm spodoptera littoralis (lepidoptera: noctuidae).the biological activity of crude petroleum ether extracts of oshar (calotropis procera); harmal (rhazya stricta) and hargal (solenostemma argel) were assessed using the 4th larval instar of cotton leafworm spodoptera littoralis (boisd.) (lepidoptera: noctuidae). all extracts exhibited a significant antifeedant activity at the lc50 levels. harmal extract deterred feeding potential of insect larvae by 52.96% but decreased to 26.76 and 18.00% for hargal and oshar, respectively. in nutritional assay ...200719093513
rna interference of the period gene affects the rhythm of sperm release in moths.the period (per) gene is 1 of the core elements of the circadian clock mechanism in animals from insects to mammals. in clock cells of drosophila melanogaster, per mrna and per protein oscillate in daily cycles. consistent with the molecular clock model, per moves to cell nuclei and acts as a repressor of positive clock elements. homologs of per are known in many insects; however, specific roles of per in generating output rhythms are not known for most species. the aim of this article was to de ...200919150927
the effects of different prey regimes on the proteolytic digestion of nymphs of the spined soldier bug, podisus maculiventris (hemiptera: pentatomidae).the effects of different prey regimes on the performance and digestive physiology of the spined soldier bug, podisus maculiventris (say) (hemiptera: pentatomidae), were assessed. specifically, p. maculiventris nymphs were fed on colorado potato beetle (cpb), leptinotarsa decemlineata say (coleoptera: chrysomelidae), larvae; egyptian cotton leafworm (ecw); spodoptera littoralis (boisduval) (lepidoptera: noctuidae); larvae; calliphora spp. (cal) (diptera: calliphoridae) pupae or a mixture of the t ...200919203402
clock-controlled rhythm of ecdysteroid levels in the haemolymph and testes, and its relation to sperm release in the egyptian cotton leafworm, spodoptera littoralis.in spodoptera littoralis, testicular sperm release occurs in a daily rhythm, which is controlled by endogenous circadian oscillator located in the male reproductive system. although this rhythm is essential for male fertility, factors that initiate and maintain daily sperm release are not understood. in this study, we investigated a modulatory role for ecdysteroids in the sperm release rhythm and identified the source of ecdysteroids in adult males. we found that the onset of sperm release occur ...200919233333
morphological and ecological characterization of steinernema feltiae (rhabditida: steinernematidae) rioja strain isolated from bibio hortulanus (diptera: bibionidae) in spain.a new strain of steinernema feltiae (rhabditida: steinernematidae) was isolated in la rioja (spain) from larvae of bibio hortulanus (diptera: bibionidae). a comparative morphometric analysis of this new strain and four additional s. feltiae isolates was performed. although significant differences in morphometric measurements were observed, pcr-rflp profiles and sequence analysis of the its region of rdna confirmed the identity of the new strain as a2 rflp type of s. feltiae. a comparative morpho ...200619259432
signal signature of aboveground-induced resistance upon belowground herbivory in maize.plants activate local and systemic defence mechanisms upon exposure to stress. this innate immune response is partially regulated by plant hormones, and involves the accumulation of defensive metabolites. although local defence reactions to herbivores are well studied, less is known about the impact of root herbivory on shoot defence. here, we examined the effects of belowground infestation by the western corn rootworm diabrotica virgifera virgifera on aboveground resistance in maize. belowgroun ...200919392694
peripheral modulation of olfaction by physiological state in the egyptian leaf worm spodoptera littoralis (lepidoptera: noctuidae).insects show behavioural plasticity based on their physiological state. deprivation from a resource will normally make them more responsive to it or to perform behaviour increasing the probability of encountering such a resource. modulation of the olfactory system has been shown mainly in the central nervous system, but also in the periphery. in this study, antennal sensitivity of females of the egyptian cotton leaf worm spodoptera littoralis to different plant and sex pheromone odours was measu ...200919414013
spodoptera littoralis-induced lectin expression in tobacco.the induced defense response in plants towards herbivores is mainly regulated by jasmonates and leads to the accumulation of so-called jasmonate-induced proteins. recently, a jasmonate (ja) inducible lectin called nicotiana tabacum agglutinin or nictaba was discovered in tobacco (n. tabacum cv samsun) leaves. tobacco plants also accumulate the lectin after insect attack by caterpillars. to study the functional role of nictaba, the accumulation of the ja precursor 12-oxophytodienoic acid (opda), ...200919416954
heterologous expression of bacillus thuringiensis vegetative insecticidal protein-encoding gene vip3lb in photorhabdus temperata strain k122 and oral toxicity against the lepidoptera ephestia kuehniella and spodoptera littoralis.photorhabdus temperata and bacillus thuringiensis are entomopathogenic bacteria exhibiting toxicities against different insect larvae. vegetative insecticidal protein vip3lb is a bacillus thuringiensis insecticidal protein secreted during the vegetative growth stage exhibiting lepidopteran specificity. in this study, we focused for the first time on the heterologous expression of vip3lb gene in photorhabdus temperata strain k122. firstly, western blot analyses of whole cultures of recombinant ph ...200919462262
pban receptor: employment of anti-receptor antibodies for its characterization and for development of a microplate binding assay.this study describes generation of an anti-pban receptor (pban-r) antiserum and its employment for the characterization of the pk/pban-r(s). the antiserum recognized, in a specific and dose-dependent manner, the presence of pban-r in pheromone gland membrane preparations of three female moths: heliothis peltigera, helicoverpa armigera and spodoptera littoralis. it also reacted specifically with the s. littoralis larval receptor in vivo, most likely by competing with the ligand on the binding sit ...200919482031
ala-val-phe and val-phe: ace inhibitory peptides derived from insect protein with antihypertensive activity in spontaneously hypertensive rats.in this study, we evaluated the stability/bioavailability and in vivo antihypertensive activity of the tripeptide, ala-val-phe, that was recently purified from insect protein (spodoptera littoralis; lepidoptera) and that showed in vitro angiotensin converting enzyme (ace) inhibitory activity. this tripeptide is partly hydrolyzed by mucosal peptidases to val-phe, a more potent in vitro ace inhibitor. in organ bath experiments using rat aorta, val-phe showed ace inhibition, while ala-val-phe did n ...201019524628
potential of "lure and kill" in long-term pest management and eradication of invasive species."lure and kill" technology has been used for several decades in pest management and eradication of invasive species. in lure and kill, the insect pest attracted by a semiochemical lure is not "entrapped" at the source of the attractant as in mass trapping, but instead the insect is subjected to a killing agent, which eliminates affected individuals from the population after a short period. in past decades, a growing scientific literature has been published on this concept. this article provides ...200919610395
characterization of xenorhabdus isolates from la rioja (northern spain) and virulence with and without their symbiotic entomopathogenic nematodes (nematoda: steinernematidae).eighteen xenorhabdus isolates associated with spanish entomopathogenic nematodes of the genus steinernema were characterized using a polyphasic approach including phenotypic and molecular methods. two isolates were classified as xenorhabdus nematophila and were associated with steinernema carpocapsae. sixteen isolates were classified as xenorhabdus bovienii, of which fifteen were associated with steinernema feltiae and one with steinernema kraussei. two x. bovienii phase ii were also isolated, o ...200919682458
identification and expression profile of halloween genes involved in ecdysteroid biosynthesis in spodoptera littoralis.20-hydroxyecdyone (20e), an active form of ecdysteroid, is the key hormone in insect growth and development. the biosynthesis of ecdysteroid is triggered and under the control of the neuropeptide, prothoracicotropic hormone (ptth). to date, five cytochrome p450 enzymes, namely spook (spo), phantom (phm), disembodied (dib), shadow (sad) and shade (shd) related to ecdysteroid biosynthesis, are identified and the character of last four enzymes is well studied in drosophila melanogaster, bombyx mori ...201019682519
insecticidal activity of scorpion toxin (butait) and snowdrop lectin (gna) containing fusion proteins towards pest species of different orders.the toxicity of a fusion protein, butalt/gna, comprising a venom toxin (butait) derived from the red scorpion, mesobuthus tamulus (f.), and galanthus nivalis agglutinin (gna), was evaluated under laboratory conditions against several pest insects. insecticidal activity was compared with sfi1/gna, a fusion comprising a venom toxin (sfi1) derived from the european spider segestria florentina (rossi) and gna, which has been previously demonstrated to be effective against lepidopteran and hemipteran ...201019728320
the dlt operon of bacillus cereus is required for resistance to cationic antimicrobial peptides and for virulence in insects.the dlt operon encodes proteins that alanylate teichoic acids, the major components of cell walls of gram-positive bacteria. this generates a net positive charge on bacterial cell walls, repulsing positively charged molecules and conferring resistance to animal and human cationic antimicrobial peptides (amps) in gram-positive pathogenic bacteria. amps damage the bacterial membrane and are the most effective components of the humoral immune response against bacteria. we investigated the role of t ...200919767427
identification of an atypical insect olfactory receptor subtype highly conserved within noctuids.olfaction is primarily mediated by the large family of olfactory receptors. although all insect olfactory receptors share the same structure with seven transmembrane domains, they present poor sequence homologies within and between species. as the only exception, drosophila melanogaster or83b and its orthologues define a receptor subtype singularly conserved between insect species. in this article, we report the identification of a new subtype of putative olfactory receptors exceptionally conser ...200919804411
the phytohormone precursor opda is isomerized in the insect gut by a single, specific glutathione transferase.oxylipins play important roles in stress signaling in plants. the compound 12-oxophytodienoic acid (cis-opda) is an early biosynthetic precursor of jasmonic acid (ja), the key phytohormone orchestrating the plant anti-herbivore defense. when consumed by feeding lepidopteran larvae, plant-derived cis-opda suffers rapid isomerization to iso-opda in the midgut and is excreted in the frass. unlike opda epimerization (yielding trans-opda), the formation of iso-opda is enzyme-dependent, and is catalyz ...200919805297
belowground aba boosts aboveground production of dimboa and primes induction of chlorogenic acid in maize.plants are important mediators between above- and belowground herbivores. consequently, interactions between root and shoot defenses can have far-reaching impacts on entire food webs. we recently reported that infestation of maize roots by larvae of the beetle diabrotica virgifera virgifera induced shoot resistance against herbivores and pathogens. root herbivory also enhanced aboveground dimboa and primed for enhanced induction of chlorogenic acid, two secondary metabolites that have been assoc ...200919820311
venom of the egg-larval parasitoid chelonus inanitus is a complex mixture and has multiple biological effects.the egg-larval parasitoid chelonus inanitus injects bracoviruses (bvs) and venom along with the egg into the host egg; both components are essential for successful parasitoid development. all stages of eggs of its natural host, spodoptera littoralis, can be successfully parasitized, i.e. from mainly a yolk sphere to a fully developed embryo. here, we show that the venom contains at least 25 proteins with masses from 14kda to over 300kda ranging from acidic to basic. the majority is glycosylated ...201020006617
synthesis and insecticidal activity of heptafluoroisopropyl-containing benzoylphenylurea structures.fourteen novel heptafluoroisopropyl-containing benzoylphenylureas were designed and synthesized. their insecticidal activities against armyworm ( pseudaletia separata walker) were examined and compared with the commercial product diflubenzuron. three compounds (iii, iij, and iik) showed excellent insecticidal effect, and their activity resembled that of diflubenzuron. compound iii also showed nearly the same insecticidal activity as novaluron on african cotton leafworm ( spodoptera littoralis ). ...201020014763
nicotiana tabacum agglutinin is active against lepidopteran pest insects.a jasmonate-inducible lectin called nicotiana tabacum agglutinin or nictaba was found in tobacco (nicotiana tabacum cv samsun) leaves. since nictaba expression is also induced after insect herbivory, a role in the defence response of tobacco was suggested. in this report, a detailed analysis was made of the entomotoxic properties of nictaba using different transgenic approaches. first, purified nictaba was shown to be strongly resistant to proteolytic degradation by enzymes present in the lepido ...201020018900
screening of uruguayan plants for deterrent activity against insects.we evaluated the anti-insectan activity of extracts from different vegetative parts of ten plant species native to uruguay. the selected plants belong to five families: bignoniaceae: clytostoma callistegioides, dolichandra cynanchoides, macfadyena unguis-cati; sapindaceae: dodonaea viscosa, allophylus edulis, serjania meridionalis; lamiaceae: salvia procurrens, salvia guaranitica; solanaceae: lycium cestroides; and phytolaccaceae: phytolacca dioica. the extracts were evaluated in independent bio ...020046902
assessment of species specificity of moulting accelerating compounds in lepidoptera: comparison of activity between bombyx mori and spodoptera littoralis by in vitro reporter and in vivo toxicity assays.dibenzoylhydrazine analogues have been developed successfully as a new group of insect growth regulators, called ecdysone agonists or moulting accelerating compounds. a notable feature is their high activity against lepidopteran insects, raising the question as to whether species-specific analogues can be isolated. in this study, the specificity of ecdysone agonists was addressed through a comparative analysis in two important lepidopterans, the silkworm bombyx mori l. and the cotton leafworm sp ...201020069627
r2r3-namyb8 regulates the accumulation of phenylpropanoid-polyamine conjugates, which are essential for local and systemic defense against insect herbivores in nicotiana attenuata.although phenylpropanoid-polyamine conjugates (ppcs) occur ubiquitously in plants, their biological roles remain largely unexplored. the two major ppcs of nicotiana attenuata plants, caffeoylputrescine (cp) and dicaffeoylspermidine, increase dramatically in local and systemic tissues after herbivore attack and simulations thereof. we identified namyb8, a homolog of ntmybjs1, which in by-2 cells regulates ppc biosynthesis, and silenced its expression by rna interference in n. attenuata (ir-myb8), ...201020089770
insect eggs suppress plant defence against chewing herbivores.plants activate direct and indirect defences in response to insect egg deposition. however, whether eggs can manipulate plant defence is unknown. in arabidopsis thaliana, oviposition by the butterfly pieris brassicae triggers cellular and molecular changes that are similar to the changes caused by biotrophic pathogens. in the present study, we found that the plant defence signal salicylic acid (sa) accumulates at the site of oviposition. this is unexpected, as the sa pathway controls defence aga ...201020230509
penetration and biodegradation of carbaryl in susceptible and resistant strains of the egyptian cotton leafworm. 197120333837
identification and functional analysis of the putative anti-apoptotic gene iap4 of spodoptera litura nucleopolyhedrovirus.baculoviruses possess two types of anti-apoptotic genes, p35 and inhibitor of apoptosis (iap). in this study, we cloned a novel iap family member, splt-iap4, from spodoptera litura nucleopolyhedrovirus (spltnpv). scanprosite analysis of splt-iap4 amino acid sequence show that it contain a baculovirus iap repeat (bir) motif at the n-terminal portion from 18 to 61 amino acid and a zinc finger ring motif near its c-terminus. baculovirus iaps could be divided into five types from iap1 to iap5 accord ...201020625923
imd pathway is involved in the interaction of drosophila melanogaster with the entomopathogenic bacteria, xenorhabdus nematophila and photorhabdus luminescens.xenorhabdus nematophila/steinernema carpocapsae and photorhabdus luminescens/heterorhabditis bacteriophora are nemato-bacterial complexes highly pathogenic for insects. using a syringe as artificial vector, we have analyzed the effects of the two bacteria, x. nematophila and p. luminescens on the genetic tool insect, drosophila melanogaster. both bacteria were found to kill adult flies in a dose dependent manner with x. nematophila being the fastest. on the other hand, when an injection of non-p ...201020627393
expression of pheromone biosynthesis activating neuropeptide and its receptor (pbanr) mrna in adult female spodoptera exigua (lepidoptera: noctuidae).the full-length cdna of pheromone biosynthesis activating neuropeptide receptor (pbanr) was cloned from the beet armyworm, spodoptera exigua (hübner) (lepidoptera: noctuidae); it included an open reading frame of 1,053 bp encoding 350 amino acids. the pbanr of s. exigua (sepbanr) was structurally characteristic of g protein-coupled receptor and its amino acid sequence shared 98% identity with the pbanr of spodoptera littoralis. both pheromone biosynthesis activating neuropeptide (pban) and pbanr ...201020665850
the role of abscisic acid and water stress in root herbivore-induced leaf resistance.• herbivore-induced systemic resistance occurs in many plants and is commonly assumed to be adaptive. the mechanisms triggered by leaf-herbivores that lead to systemic resistance are largely understood, but it remains unknown how and why root herbivory also increases resistance in leaves. • to resolve this, we investigated the mechanism by which the root herbivore diabrotica virgifera induces resistance against lepidopteran herbivores in the leaves of zea mays. • diabrotica virgifera infested pl ...201120840610
flufenerim, a novel insecticide acting on diverse insect pests: biological mode of action and biochemical aspects.a new chemical compound was tested for its insecticidal activity against several major insect pests. the compound, called "flufenerim", has a core pyrimidine structure and an unknown mode of action and showed potent activity against the sweet potato whitefly bemisia tabaci (gennadius), the green peach aphid myzus persicae (sulzer), and the african cotton leafworm spodoptera littoralis (boisduval); however, it did not show any activity against two thrips species: western flower thrips frankliniel ...201020958045
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