| molecular characterization of the first intact transib transposon from helicoverpa zea. | transib is a superfamily of dna transposons recently reconstructed in silico from degenerate elements in the genomes of drosophila melanogaster and anopheles gambiae. here we report characterization of the first intact transib transposon designated hztransib from helicoverpa zea. at least two hztransib copies (one full-length, one internally-deleted) exist in the genomes of a midgut cell line and a laboratory strain of h. zea. the full-length hztransib has 3518 bp including a 5' terminal inverte ... | 2008 | 18031956 |
| effects of defoliating insect resistance qtls and a cry1ac transgene in soybean near-isogenic lines. | the crystal proteins coded by transgenes from bacillus thuringiensis (bt) have shown considerable value in providing effective insect resistance in a number of crop species, including soybean, glycine max (l.) merr. additional sources of soybean insect resistance would be desirable to manage the development of tolerance/resistance to crystal proteins by defoliating insects and to sustain the deployment of bt crops. the objective of this study was to evaluate the effects and interactions of three ... | 2008 | 18064435 |
| diapause hormone in the corn earworm, helicoverpa zea: optimum temperature for activity, structure-activity relationships, and efficacy in accelerating flesh fly pupariation. | diapause hormone (dh) effectively terminated pupal diapause in helicoverpa zea. this effect was temperature-dependent, with an optimum of 21 degrees c. the dose-response curve indicated an ed50 of dh for diapause termination of approximately 100 pmol. the core sequence and essential amino acids were determined by bioassays using modified and truncated dh analogs. a c-terminal hepta-peptide, lwfgprla, was the core sequence required for diapause termination. activity was lost when alanine was subs ... | 2008 | 18206265 |
| insect resistance to bt crops: evidence versus theory. | evolution of insect resistance threatens the continued success of transgenic crops producing bacillus thuringiensis (bt) toxins that kill pests. the approach used most widely to delay insect resistance to bt crops is the refuge strategy, which requires refuges of host plants without bt toxins near bt crops to promote survival of susceptible pests. however, large-scale tests of the refuge strategy have been problematic. analysis of more than a decade of global monitoring data reveals that the fre ... | 2008 | 18259177 |
| responses of helicoverpa armigera to tomato plants previously infected by tomv or damaged by h. armigera. | we report the comparative inducing effects of a phytopathogen and a herbivorous arthropod on the performance of an herbivore. tomato, lycopersicon esculentum mill., was used as the test plant, and tomato mosaic virus (tomv) and corn earworm, helicoverpa armigera hübner, were used as the phytopathogen and herbivore, respectively. there were decreases in the efficiency of conversion of ingested food and efficiency of conversion of digested food when h. armigera was reared on tomato plants that had ... | 2008 | 18286340 |
| a naturally occurring plant cysteine protease possesses remarkable toxicity against insect pests and synergizes bacillus thuringiensis toxin. | when caterpillars feed on maize (zea maize l.) lines with native resistance to several lepidopteran pests, a defensive cysteine protease, mir1-cp, rapidly accumulates at the wound site. mir1-cp has been shown to inhibit caterpillar growth in vivo by attacking and permeabilizing the insect's peritrophic matrix (pm), a structure that surrounds the food bolus, assists in digestion and protects the midgut from microbes and toxins. pm permeabilization weakens the caterpillar defenses by facilitating ... | 2008 | 18335057 |
| new cell lines derived from the black cutworm, agrotis ipsilon, that support replication of the a. ipsilon multiple nucleopolyhedrovirus and several group i nucleopolyhedroviruses. | new cell lines were recently developed from the embryos of the black cutworm, agrotis ipsilon (lepidoptera: noctuidae). a primary culture was initiated from 4-day-old a. ipsilon eggs in excell420 medium supplemented with 5% fetal bovine serum. this initial culture produced sufficient cell growth to allow subcultivation and eventually led to the establishment of eight distinct strains. two of these strains (aie1611t and aied6t) were selected for further characterization. extracts of these strains ... | 2008 | 18395741 |
| toxicity and characterization of cotton expressing bacillus thuringiensis cry1ac and cry2ab2 proteins for control of lepidopteran pests. | cry1ac protoxin (the active insecticidal toxin in both bollgard and bollgard ii cotton [gossypium hirsutum l.]), and cry2ab2 toxin (the second insecticidal toxin in bollgard ii cotton) were bioassayed against five of the primary lepidopteran pests of cotton by using diet incorporation. cry1ac was the most toxic to heliothis virescens (f.) and pectinophora gossypiella (saunders), demonstrated good activity against helicoverpa zea (boddie), and had negligible toxicity against spodoptera exigua (hü ... | 2008 | 18459423 |
| interspecific pheromone plume interference among sympatric heliothine moths: a wind tunnel test using live, calling females. | three species of north american heliothine moths were used to determine the level at which interspecific female interference of male attraction to conspecific females occurs. we used live calling females of heliothis virescens, h. subflexa, and helicoverpa zea, as lures for conspecific males in a wind tunnel, and then placed heterospecific females on either side of the original species such that the plumes of the three females overlapped downwind. in nearly all combinations, in the presence of h ... | 2008 | 18461401 |
| slow cell infection, inefficient primary infection and inability to replicate in the fat body determine the host range of thysanoplusia orichalcea nucleopolyhedrovirus. | thysanoplusia orichacea multicapsid nucleopolyhedrovirus (thormnpv) carrying an enhanced green fluorescent protein (egfp) gene expression cassette (vthgfp) was used to study host-range mechanisms. infection kinetics showed that vthgfp replication in sf21 cells was too slow to suppress cell growth. wide-host-range autographa californica mnpv (acmnpv) could speed up vthgfp infection and enhance the vthgfp infection rate in sf21 cells. the enhancement was not due to recombination, as no recombinant ... | 2008 | 18474556 |
| aflatoxin b1 detoxification by cyp321a1 in helicoverpa zea. | the polyphagous corn earworm helicoverpa zea frequently encounters aflatoxins, mycotoxins produced by the pathogens aspergillus flavus and a. parasiticus, which infect many of this herbivore's host plants. while aflatoxin b1 metabolism by midgut enzymes isolated from fifth instars feeding on control diets was not detected, this compound was metabolized by midgut enzymes isolated from larvae consuming diets supplemented with xanthotoxin, coumarin, or indole-3-carbinol, phytochemicals that are lik ... | 2008 | 18615618 |
| fmrf-amide immunoreactivity in a moth larva (heliothis zea): the cerebral nervous system. | the cerebral nervous system of the larval corn earworm, heliothis zea, was examined using light microscopy and immunocytochemistry. immunoreactivity for the molluscan cardioactive peptide fmrf-amide (fmrfa) is widely distributed. staining is localized in perikarya and axons of the brain, subesophageal ganglion and first thoracic ganglion. immunoreactive axons are also found in the frontal ganglion and the corpora cardiaca. crossreactivity studies for fmrfa and bovine pancreatic polypeptide (bpp) ... | 1989 | 18620278 |
| a new gland associated with the retrocerebral complex of the adult corn earworm, helicoverpa zea. | we report the discovery of a single-celled putative new gland associated with the retrocerebral complex in the adults of helicoverpa zea. the gland was not observed in manduca sexta and few other species of moths. the pair of glands, each 50.6+/-5.5 microm in diameter, is located on either side of the recurrent nerve. each gland is connected on one end through a fine nerve to the nervus corporis cardiaci-3 (ncc-3) and at the opposite end to the corpora allata through a thin fiber. the gland is c ... | 2008 | 18635395 |
| differences in cuticular lipid composition of the antennae of helicoverpa zea, heliothis virescens, and manduca sexta. | analyses of the hexane washes of antennae, forelegs and whole bodies of helicoverpa zea, heliothis virescens, and manduca sexta revealed notable differences in the components of the cuticular coatings of each species. most striking were the differences between the cuticular coatings of male and female antennae of both h. zea and h. virescens. novel esters of short-chain acids (c2-c4) and long-chain secondary alcohols (c25-c32) were identified in the hexane washes of the male antenna and forelegs ... | 2008 | 18703068 |
| survivorship of helicoverpa zea and heliothis virescens on cotton plant structures expressing a bacillus thuringiensis vegetative insecticidal protein. | a series of tests quantified bollworm, helicoverpa zea (boddie), and tobacco budworm, heliothis virescens (f.), larval survival on plant structures of a nontransgenic cotton (gossypium hirsutum l.), 'coker 312', and two transgenic cottons expressing vip3a protein or both vip3a + crylab proteins (vipcot). vegetative and reproductive structures including terminal leaves, flower bud (square) bracts, whole debracted squares, flower petals, flower anthers, and intact capsules (bolls) were harvested f ... | 2008 | 18767734 |
| fitness costs associated with cry1ac-resistant helicoverpa zea (lepidoptera: noctuidae): a factor countering selection for resistance to bt cotton? | the heritability, stability, and fitness costs in a cry1ac-resistant helicoverpa zea (boddie) (lepidoptera: noctuidae) colony (ar) were measured in the laboratory. in response to selection, heritability values for ar increased in generations 4-7 and decreased in generations 11-19. ar had significantly increased pupal mortality, a male-biased sex ratio, and lower mating success compared with the unselected parental strain (sc). ar males had significantly more mating costs compared with females. a ... | 2008 | 18767756 |
| identification of multiple ear-colonizing insect and disease resistance in cimmyt maize inbred lines with varying levels of silk maysin. | ninety four corn inbred lines selected from international center for the improvement of maize and wheat (cimmyt) in mexico were evaluated for levels of silk maysin in 2001 and 2002. damage by major ear-feeding insects [i.e., corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae); maize weevil, sitophilus zeamais (motschulsky) (coleoptera: curculionidae); brown stink bug, euschistus servus (say); southern green stink bugs, nezara viridula (l.) (heteroptera: pentatomidae)], and common smu ... | 2008 | 18767760 |
| cloning and characterization of the secreted hemocytic prophenoloxidases of heliothis virescens. | the plasma enzyme phenoloxidase plays an important role in host resistance against viral, bacterial, fungal, filarial, and parasitoid challenge. two heliothis virescens prophenoloxidase transcripts, hvppo-1 and hvppo-2, were assembled from ests derived from a hemocyte cdna library. the 2,363-bp hvppo-1 contig encoded a 696-amino acid protein. the 3,255-bp hvppo-2 contig encoded a 684-amino acid protein. hemocyte and fat body transcript levels of hvppo-1 were slightly elevated by bacterial infect ... | 2008 | 18839417 |
| specific binding of bacillus thuringiensis cry2a insecticidal proteins to a common site in the midgut of helicoverpa species. | for a long time, it has been assumed that the mode of action of cry2a toxins was unique and different from that of other three-domain cry toxins due to their apparent nonspecific and unsaturable binding to an unlimited number of receptors. however, based on the homology of the tertiary structure among three-domain cry toxins, similar modes of action for all of them are expected. to confirm this hypothesis, binding assays were carried out with (125)i-labeled cry2ab. saturation assays showed that ... | 2008 | 18931285 |
| yield response of dual-toxin bt cotton to helicoverpa zea infestations. | field cage experiments were conducted to determine the impact of bollworms, helicoverpa zea (boddie), on yields of bollgard ii and widestrike cotton, gossypium hirsutum l. one-day-old bollworm larvae were infested in white flowers of bollgard ii and in white flowers and terminals of widestrike cotton. the infestation levels included 0, 50, and 100% of white flowers for each type of cotton. terminal infestations included one or two larvae per terminal on widestrike cotton. larvae were placed in f ... | 2008 | 18950041 |
| transfection of insect cell lines using polyethylenimine. | insect cell lines have been widely used in recombinant baculovirus expression systems and transient gene expression studies. critical to these applications have been the transfection of foreign dna. this has been frequently done using labor intensive and cytotoxic liposome-based transfection reagents. in the current study we have optimized a new kind of polyethylenimine-based dna transfection reagent on the spodoptera frugiperda sf9 insect cell line. a plasmid vector that transiently expresses g ... | 2006 | 19002899 |
| growth, viral production and metabolism of a helicoverpa zea cell line in serum-free culture. | insect cell cultures have been extensively utilised for means of production for heterologous proteins and biopesticides. spodoptera frugiperda (sf9) and trichoplusia ni (high fivetrade mark) cell lines have been widely used for the production of recombinant proteins, thus metabolism of these cell lines have been investigated thoroughly over recent years. the helicoverpa zea cell line has potential use for the production of a biopesticide, specifically the helicoverpa armigera single-nucleocapsid ... | 2003 | 19002933 |
| effect of racemic, (+)- and (-)-gossypol on survival and development of heliothis virescens larvae. | gossypol is a constituent of the lysigenous foliar glands of cotton plants and is also found in glands in cottonseed. gossypol exists as enantiomers because of restricted rotation around the binaphthyl bond. the biological activities of the enantiomers differ. for example, (+)-gossypol can be fed safely to nonruminants such as chickens, but (-)-gossypol cannot. most commercial cottonseed contain a (+)- to (-)-gossypol ratio of approximately 3:2. conventional breeding techniques can be used to de ... | 2008 | 19036185 |
| identification and characterization of protease inhibitors in diplotaxis species. | pcr analysis of the genomes of two wild brassicaceae plants, diplotaxis muralis and diplotaxis tenuifolia, demonstrated the presence of several genes coding for potential protease inhibitors, classifiable within the mustard inhibitor family (msi). this is a small family of plant protease inhibitors named after the mustard trypsin inhibitor mti-2, the first protease inhibitor characterized in brassicaceae. from identified sequences two recombinant inhibitors were expressed in pichia pastoris. in ... | 2009 | 19070500 |
| genomic structure and promoter analysis of pathogen-induced repat genes from spodoptera exigua. | the repat gene family encodes midgut proteins overexpressed in response to pathogen infection in the lepidopteran spodoptera exigua. up-regulation of repat genes has been observed after challenging the larvae with both bacillus thuringiensis toxins and after infection with the baculovirus autographa californica multiple nucleopolyhedrovirus. in our study, pcr amplification of the genomic region and genome walking were used to obtain the genomic structure and the sequence of the 5'-upstream regio ... | 2009 | 19076251 |
| efficacy of transgenic cotton expressing cry1ac and cry1f insecticidal protein against heliothines (lepidoptera: noctuidae). | cotton, cossypium hirsutum l, plants expressing cry1ac and cry1f (phytogen 440w) insecticidal crystal proteins of bacillus thuringiensis (bt) berliner, were evaluated against natural populations of tobacco budworm, heliothis virescens (f.), and bollworm, helicoverpa zea (boddie) (lepidoptera: noctuidae), across 13 southern u.s. locations that sustained low, moderate, and high infestations. the intrinsic activity of phytogen 440w was compared with nontreated non-bt cotton (psc355) and with manage ... | 2008 | 19133479 |
| do caterpillars secrete "oral secretions"? | the oral secretions or regurgitant of caterpillars contain potent elicitors of plant induced responses. these elicitors are recognized by host plants to differentiate between simple mechanical injury and the presence of herbivores. in some cases, this level of recognition is highly specific. despite the in-depth chemical characterization of these elicitors, little is known about the amounts delivered in regurgitant during feeding. in this study, we use a fluorescent dye to label regurgitant in o ... | 2009 | 19221841 |
| multiple pest interactions in soybean: effects on heterodera glycines egg populations and crop yield. | population changes of heterodera glycines eggs on soybean in small field plots were influenced by the lepidopterous insect pest, helicoverpa zea; however, few effects on eggs due to the presence of annual weeds were detected. soybeans defoliated 15-35% by h. zea during august remained green and continued to produce new flowers and pods later into the season than soybeans without h. zea, resulting in higher numbers of h. glycines eggs at harvest on insect-defoliated soybeans. final h. glycines po ... | 1993 | 19279740 |
| evaluation of the spatial pattern of steinernema riobravis in corn plots. | the vertical and horizontal spatial patterns of a naturally occurring population of the entomopathogenic nematode steinernema riobravis (rhabditida: steinernematidae) were investigated in corn field soil by laboratory and field bioassays. this nematode appears to be endemic to the lower rio grande valley of texas, where it was found parasitizing prepupae and pupae of both corn earworm, helicoverpa zea, and fall armyworm, spodoptera frugiperda (lepidoptera: noctuidae). corn earworm prepupa was th ... | 1994 | 19279865 |
| analysis of ests generated from immune-stimulated hemocytes of larval heliothis virescens. | heliothis virescens immunome components responding to baculoviral and bacterial infection were identified from expressed sequence tags (ests) generated from an immune-stimulated larval hemocyte cdna library. a total of 5548 ests were generated comprising 448 contigs and 1114 singletons, totaling 1606 putative transcripts 1101 of which had blast scores, including many known orthologs from other insect species. orthologs of known or putative immune function were identified among them melanization ... | 2009 | 19442669 |
| optimizing helicoverpa zea (lepidoptera: noctuidae) insecticidal efficacy in minnesota sweet corn: a logistic regression to assess timing parameters. | late-season plantings of sweet corn in minnesota result in an abundant supply of silking corn, zea mays l., throughout august to early september that is highly attractive to the corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae). during a 10-yr period, 1997-2006, insecticide efficacy trials were conducted in late-planted sweet corn in minnesota for management of h. zea. these data were used to develop a logistic regression model to identify the variables and interactions that most i ... | 2009 | 19449649 |
| nudiviruses and other large, double-stranded circular dna viruses of invertebrates: new insights on an old topic. | nudiviruses (nvs) are a highly diverse group of large, circular dsdna viruses pathogenic for invertebrates. they have rod-shaped and enveloped nucleocapsids, replicate in the nucleus of infected host cells, and possess interesting biological and molecular properties. the unassigned viral genus nudivirus has been proposed for classification of nudiviruses. currently, the nudiviruses comprise five different viruses: the palm rhinoceros beetle virus (oryctes rhinoceros nv, ornv), the hz-1 virus (he ... | 2009 | 19460388 |
| bioavailability of insect neuropeptides: the pk/pban family as a case study. | the ability of unmodified linear peptides to penetrate the insect cuticle and exert bioactivity (e.g., stimulation of sex pheromone biosynthesis) was tested by topical application onto heliothis peltigera moths of four insect neuropeptides (nps) of the pyrokinin (pk)/pheromone biosynthesis activating neuropeptide (pban) family: helicoverpa zea pban (hez-pban), pseudaletia (mythimna) separata pheromonotropin (pt), leucophaea maderae pk (lpk) and locusta migratoria myotropin (lom-mt-ii). the time ... | 2009 | 19463734 |
| manduca sexta (lepidoptera: sphingidae) cadherin fragments function as synergists for cry1a and cry1c bacillus thuringiensis toxins against noctuid moths helicoverpa zea, agrotis ipsilon and spodoptera exigua. | specific bacillus thuringiensis berliner (bt) toxins are effective against a narrow spectrum of species. while specificity is an advantage for limiting adverse effects on non-target organisms, it is also the primary drawback of bt's application for controlling multiple pest species in agriculture, forestry and other areas. recently, it was reported that a small toxin-binding fragment of manduca sexta (joh.) cadherin acts as a synergist of bt toxins to m. sexta, heliothis virescens f. and helicov ... | 2009 | 19489014 |
| plasma phenoloxidase of the larval tobacco budworm, heliothis virescens, is virucidal. | heliothis virescens larval plasma contains high levels of an antiviral activity against the budded form of the helicoverpa zea single nucleopolyhedrovirus (hzsnpv) in vitro. preliminary results indicated that phenoloxidase is primarily responsible for this virucidal effect. however it is known that other enzymes that generate antimicrobial reactive oxygen intermediates and reactive nitrogen intermediates are present in hemolymph that could contribute to the observed virucidal activity. to elucid ... | 2006 | 19537988 |
| bacterial, but not baculoviral infections stimulate hemolin expression in noctuid moths. | lepidopteran larvae are regularly infected by baculoviruses during feeding on infected plants. the differences in sensitivity to these infections can be substantial, even among closely related species. for example, the noctuids cotton bollworm (helicoverpa zea) and tobacco budworm (heliothis virescens), have a 1000-fold difference in sensitivity to autographa californica multiple nucleopolyhedrovirus (acmnpv) infection. recent data were interpreted to indicate that the lepidopteran immunoglobuli ... | 2009 | 19540262 |
| synergistic interactions between cry1ac and natural cotton defenses limit survival of cry1ac-resistant helicoverpa zea (lepidoptera: noctuidae) on bt cotton. | larvae of the bollworm helicoverpa zea (boddie) show some tolerance to bacillus thuringiensis (bt) cry1ac, and can survive on cry1ac-expressing bt cotton, which should increase resistance development concerns. however, field-evolved resistance has not yet been observed. in a previous study, a population of h. zea was selected for stable resistance to cry1ac toxin. in the present study, we determined in laboratory bioassays if larvae of the cry1ac toxin-resistant h. zea population show higher sur ... | 2009 | 19588197 |
| supplemental control of lepidopterous pests on bt transgenic sweet corn with biologically-based spray treatments. | biologically-based spray treatments, including nucleopolyhedroviruses, neem, and spinosad, were evaluated as supplemental controls for the fall armyworm, spodoptera frugiperda (j. e. smith), and corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae), on transgenic sweet corn, zea mays (l.) (poales: poaceae), expressing a cry1ab toxin from bacillus thuringiensis berliner (bacillales: bacillaceae) (bt). overall, transgenic corn supported lower densities of both pests than did nontransgeni ... | 2009 | 19611255 |
| comparative toxicity of mycotoxins to navel orangeworm (amyelois transitella) and corn earworm (helicoverpa zea). | mycotoxins, such as aflatoxins and ochratoxins, are widely distributed in nature and are frequently problematic crop contaminants that cause millions of dollars of annual losses in the united states. insect infestations of crop plants significantly exacerbate mycotoxin contamination. damage to a variety of nut species by amyelois transitella walker (navel orangeworm, now) is associated with infection by aspergillus species and concomitant production of aflatoxins and ochratoxins. resistance to a ... | 2009 | 19680726 |
| molecular characterization of neuropeptide f from the eastern subterranean termite reticulitermes flavipes (kollar) (isoptera: rhinotermitidae). | neuropeptide f (npf)-like immunoreactivity was previously found to be abundant in the eastern subterranean termite, reticulitermes flavipes. purification of the npf from a whole body extract of worker termites was accomplished in the current study by hplc and heterologous radioimmunoassay for an npf-related peptide, helicoverpa zea midgut peptide-i. a partial amino acid sequence allowed determination of the corresponding cdna that encoded an open reading frame deduced for authentic r. flavipes n ... | 2010 | 19747517 |
| eicosanoids influence insect susceptibility to nucleopolyhedroviruses. | nine pharmaceutical inhibitors of eicosanoid biosynthesis (e.g., bromophenacyl bromide, clotrimazole, diclofenamic acid, esculetin, flufenamic acid, indomethacin, nimesulide, sulindac, tolfenamic acid) that increased the susceptibility of the gypsy moth, lymantria dispar (l.), to the nucleopolyhedrovirus ldmnpv were tested against the beet armyworm spodoptera exigua (hübner), the corn earworm helicoverpa zea (boddie) and the fall armyworm spodoptera frugiperda (j.e. smith) and their respective n ... | 2009 | 19761772 |
| texas is the overwintering source of fall armyworm in central pennsylvania: implications for migration into the northeastern united states. | fall armyworm, spodoptera frugiperda (j. e. smith) (lepidoptera: noctuidae), infestations in most of north america arise from annual migrations of populations that overwinter in southern texas and florida. cytochrome oxidase i haplotype profiles within the fall armyworm corn strain, the subgroup that preferentially infests corn (zea mays l.), can differentiate the texas and florida populations. we use this molecular metric to show that fall armyworms in central pennsylvania originate from texas, ... | 2009 | 20021748 |
| activity of oil-formulated conidia of the fungal entomopathogens nomuraea rileyi and isaria tenuipes against lepidopterous larvae. | the fungi nomuraea rileyi and isaria tenuipes (=paecilomyces tenuipes) are ecologically obligate, widespread pathogens of lepidopterans. bioassays were carried out to evaluate the activity of oil-suspended conidia of n. rileyi and i. tenuipes against larvae of spodoptera frugiperda, spodoptera exigua, helicoverpa zea, and heliothis virescens. the tests consisted of two bioassay sets. in the first set, conidia of n. rileyi and i. tenuipes were suspended in water+tween 80, and in vegetable (canola ... | 2010 | 20025883 |
| comparative virulence of beauveria bassiana isolates against lepidopteran pests of vegetable crops. | forty-three isolates of the entomopathogenic fungus beauveria bassiana were screened for virulence against second-instar larvae of diamondback moth (plutella xylostella) (dbm), european corn borer (ostrinia nubilalis) (ecb), corn earworm (helicoverpa zea) (cew), and fall armyworm (spodoptera frugiperda) (faw); 30 of these isolates were tested against beet armyworm (spodoptera exigua) (baw). highly virulent isolates were also tested against black cutworm (agrotis ipsilon) (bcw), and the most viru ... | 2010 | 20060396 |
| field-evolved insect resistance to bt crops: definition, theory, and data. | transgenic crops producing bacillus thuringiensis (bt) toxins for insect pest control have been successful, but their efficacy is reduced when pests evolve resistance. here we review the definition of field-evolved resistance, the relationship between resistance and field control problems, the theory underlying strategies for delaying resistance, and resistance monitoring methods. we also analyze resistance monitoring data from five continents reported in 41 studies that evaluate responses of fi ... | 2009 | 20069826 |
| associations of planting date, drought stress, and insects with fusarium ear rot and fumonisin b1 contamination in california maize. | fusarium ear rot, caused by fusarium verticillioides, is one of the most common diseases of maize, causing yield and quality reductions and contamination of grain by fumonisins and other mycotoxins. drought stress and various insects have been implicated as factors affecting disease severity. field studies were conducted to evaluate the interactions and relative influences of drought stress, insect infestation, and planting date upon fusarium ear rot severity and fumonisin b1 contamination. thre ... | 2010 | 20127546 |
| intraguild competition and enhanced survival of western bean cutworm (lepidoptera: noctuidae) on transgenic cry1ab (mon810) bacillus thuringiensis corn. | the effect of genetically modified corn (event mon810, yieldgard corn borer) expressing the bacillus thuringiensis sp. kurstaki (berliner) (bt) endotoxin, cry1ab, on the survival of western bean cutworm, striacosta albicosta (smith), larvae was examined during intraguild competition studies with either european corn borer, ostrinia nubilalis (hübner), or corn earworm, helicoverpa zea (boddie), larvae. competition scenarios were constructed by using either a laboratory or field competition arena ... | 2010 | 20214368 |
| distribution of neuropeptide f-like immunoreactivity in the eastern subterranean termite, reticulitermes flavipes. | the nervous system and gut of worker, soldier and alate castes of the eastern subterranean termite, reticulitermes flavipes kollar (isoptera: rhinotermitidae) were examined for immunoreactivity to an antiserum to helicoverpa zea (boddie) (leipidoptera: noctuidae) mp-i (qaarprf-nh(2)), a truncated form of neuropeptide f. more than 145 immunostained axons and cell bodies were seen in the brain and all ganglia of the ventral nerve cord. immunoreactive axons exiting the brain projected anteriorly to ... | 2008 | 20302462 |
| isolation and characterization of a baculovirus associated with the insect parasitoid wasp, cotesia marginiventris, or its host, trichoplusia ni. | a multiple nucleopolyhedrovirus (mnpv) was isolated from trichoplusia ni (hübner) (lepidoptera: noctuidae) larvae that had been stung by the parasitoid cotesia marginiventris (cresson) (hymenoptera: braconidae). the wild type virus was plaque purified by infecting a heliothis subflexa (bcirl- hsam1) cell line and isolating several clones. the mean estimated genomic size of this virus based on psti, bsteii, styi, hindiii restriction profiles was estimated to be 106 +/- 2.5 kbp (mean+/-se). a clon ... | 2008 | 20334593 |
| effects of vegetated field borders on arthropods in cotton fields in eastern north carolina. | the influence, if any, of 5m wide, feral, herbaceous field borders on pest and beneficial arthropods in commercial cotton, gossypium hirsutum (l.) (malvales: malvaceae), fields was measured through a variety of sampling techniques over three years. in each year, 5 fields with managed, feral vegetation borders and five fields without such borders were examined. sampling was stratified from the field border or edge in each field in an attempt to elucidate any edge effects that might have occurred. ... | 2008 | 20345293 |
| suitability of different lepidopteran host species for development of bracon hebetor (hymenoptera: braconidae). | bracon hebetor say (hymenoptera: braconidae) is a gregarious larval ectoparasitoid of several species of lepidoptera that are associated with stored products. the suitability of 12 potential lepidopteran host species representing four families was studied in this study for the development and reproduction of b. hebetor. the lepidoptera species used were the indianmeal moth, plodia interpunctella (hübner), mediterranean flour moth, ephestia kuehniella (zeller), almond moth, e. cautella (walker), ... | 2010 | 20388274 |
| egf1.5 is a second phenoloxidase cascade inhibitor encoded by microplitis demolitor bracovirus. | the three-member egf gene family from the polydnavirus microplitis demolitor bracovirus (mdbv) encodes novel proteins distinguished by a shared cysteine-rich motif. prior studies determined that one family member, egf1.0, inhibits melanization of hemolymph from the moth manduca sexta by disabling phenoloxidase activating proteinases (paps). here we characterized a second family member, egf1.5, which shares an identical cysteine-rich motif with egf1.0, but possesses an extended c-terminal repeat ... | 2010 | 20417280 |
| analysis by phage display selection and site-directed retromutagenesis of the mustard trypsin inhibitor 2 reactive site. | the mustard trypsin inhibitor (msi) family is a small family of plant protease inhibitors so far only found in brassicaceae. using a phage display selection, mti-2 (mustard trypsin inhibitor 2) mutants were detected and analysed for their biochemical characteristics. retromutants of the selected mti-2 proteins were constructed and expressed in the pichia pastoris system. the recombinant proteins were analysed by activity assays against bovine trypsin and helicoverpa zea trypsin, and by circular ... | 2010 | 20692717 |
| comparative kinetics of fatty acid-amino acid conjugate elicitor biosynthesis by midgut tissue microsomes of lepidopterous caterpillar larvae. | n-linolenoyl-l-glutamine is one of several structurally similar fatty acid-amino acid conjugate (fac) elicitors found in the oral secretions of lepidopterous caterpillars and its biosynthesis is catalyzed by membrane-associated alimentary tissue enzyme(s). fac elicitors comprise 17-hydroxylated or non-hydroxylated linolenic acid coupled with l-glutamine or l-glutamate by an amide bond. we demonstrate in vitro biosynthesis of n-linolenoyl-l-glutamine by manduca sexta, heliothis virescens, and hel ... | 2010 | 21104884 |
| agroinfiltration as a technique for rapid assays for evaluating candidate insect resistance transgenes in plants. | functional analysis of candidate transgenes for insect resistance in stably transformed plants is a time-consuming task that can take months to achieve in even the fastest of plant models. in this study, a rapid screening technique is described, which employs candidate transgene transient expression using agroinfiltration in nicotiana benthamiana combined with a simple insect bioassay. using this system the known insecticidal protein cry1ac is demonstrated to effectively control helicoverpa zea. ... | 2010 | 21140154 |
| development of insect-resistant transgenic cotton with chimeric tvip3a* accumulating in chloroplasts. | an optimized vip3a gene, designated as vip3a* was chemically synthesized and a thi1 gene chloroplast transit peptide coding sequence was attached to its 5' end to produce the tvip3a*. vip3a* and tvip3a* genes were transformed into gossypium hirsutum cv. zhongmiansuo35. of 42 independent transformants, 36 were positive for the vip3a* or tvip3a* gene. four independent transgenic t1 lines with single-copy insertions and unchanged phenotypes (ctv1 and ctv2 for tvip3a*, and cv1 and cv2 for vip3a*) we ... | 2011 | 21246398 |
| genetic variation and virulence of nucleopolyhedroviruses isolated worldwide from the heliothine pests helicoverpa armigera, helicoverpa zea, and heliothis virescens. | to assess the diversity and relationships of baculoviruses found in insects of the heliothine pest complex, a pcr-based method was used to classify 90 samples of nucleopolyhedrovirus (npv; baculoviridae: alphabaculovirus) obtained worldwide from larvae of heliothis virescens, helicoverpa zea, and helicoverpa armigera. partial nucleotide sequencing and phylogenetic analysis of three highly conserved genes (lef-8, lef-9, and polh) indicated that 67 of these samples contained isolates of the h. zea ... | 2011 | 21439295 |
| differential activity of multiple saponins against omnivorous insects with varying feeding preferences. | a variety of glycosylated and unglycosylated saponins from seven different plant families (aquifoliaceae, asparagaceae, caryophyllaceae, dioscoreaceae, leguminosae, rosaceae, sapindaceae) were tested against the corn earworm, helicoverpa zea, and the fall armyworm, spodoptera frugiperda. the corn earworm feeds readily on both monocots and dicots, while the fall armyworm is primarily a grass feeder. most of the saponins were similarly effective or ineffective against both insect species, with the ... | 2011 | 21503618 |
| novel vip3a bacillus thuringiensis (bt) maize approaches high-dose efficacy against helicoverpa zea (lepidoptera: noctuidae) under field conditions: implications for resistance management. | sweet corn, zea mays l., transformed to express a novel vegetative insecticidal protein, vip3a (event mir162, syngenta seeds, inc..), produced by the bacterium, bacillus thuringiensis (bt), was evaluated over four field seasons in maryland and two field seasons in minnesota for efficacy against the corn earworm, helicoverpa zea (boddie). -áhybrids expressing the vip3a protein and pyramided in hybrids also expressing the cry1ab bt protein (event bt11, attribute (-«) , syngenta seeds, inc.) were c ... | 2010 | 21844691 |
| a host-plant specialist, helicoverpa assulta, is more tolerant to capsaicin from capsicum annuum than other noctuid species. | plant secondary compounds not only play an important role in plant defense, but have been a driving force for host adaptation by herbivores. capsaicin (8-methyl-n-vanillyl-6-nonenamide), an alkaloid found in the fruit of capsicum spp. (solanaceae), is responsible for the pungency of hot pepper fruits and is unique to the genus. the oriental tobacco budworm, helicoverpa assulta (lepidoptera: noctuidae), is a specialist herbivore feeding on solanaceous plants including capsicum annuum, and is one ... | 2011 | 21704632 |
| noctuid migration in texas within the nocturnal aeroecological boundary layer. | long-distance migration of adult corn earworm moths (helicoverpa zea), and several other noctuid moth species, facilitates seasonal expansion of pest populations and consequent increased infestations of agricultural crops on a continental scale in north america. long-term field studies of population dynamics and migratory flights of h. zea and fall armyworm (spodoptera frugiperda) in the united states were evaluated using x-band radar observations and profiles of atmospheric conditions. these st ... | 2008 | 21669776 |
| impact of applying edible oils to silk channels on ear pests of sweet corn. | the impact of applying edible oils to corn silks on ear-feeding insects in sweet corn, zea mays l., production was evaluated in 2006 and 2007. six edible oils used in this experiment were canola, corn, olive, peanut, sesame, and soybean. water and two commercial insecticidal oils (neemix neem oil and nc21 sunspray ultrafine, a horticultural mineral oil) were used as the controls for the experiment. six parameters evaluated in this experiment were corn earworm [helicoverpa zea (boddie) (lepidopte ... | 2011 | 21735916 |
| Spatial patterns of aflatoxin levels in relation to ear-feeding insect damage in pre-harvest corn. | Key impediments to increased corn yield and quality in the southeastern US coastal plain region are damage by ear-feeding insects and aflatoxin contamination caused by infection of Aspergillus flavus. Key ear-feeding insects are corn earworm, Helicoverpa zea, fall armyworm, Spodoptera frugiperda, maize weevil, Sitophilus zeamais, and brown stink bug, Euschistus servus. In 2006 and 2007, aflatoxin contamination and insect damage were sampled before harvest in three 0.4-hectare corn fields using a ... | 2011 | 22069748 |
| baculovirus induced transcripts in hemocytes from the larvae of heliothis virescens. | using rna-seq digital difference expression profiling methods, we have assessed the gene expression profiles of hemocytes harvested from heliothis virescens that were challenged with helicoverpa zea single nucleopolyhedrovirus (hzsnpv). a reference transcriptome of hemocyte-expressed transcripts was assembled from 202 million 42-base tags by combining the sequence data of all samples, and the assembled sequences were then subject to blastx analysis to determine gene identities. we used the fully ... | 2011 | 22163334 |
| development of quenching and washing protocols for quantitative intracellular metabolite analysis of uninfected and baculovirus-infected insect cells. | metabolomics refer to the global analysis of small molecule metabolites in a biological system, and can be a powerful tool to elucidate and optimize cellular processes, particularly when integrated into a systems biology framework. determining the endometabolome in cultured animal cells is especially challenging, due to the conflicting demands for rapid quenching of metabolism and retention of membrane integrity, while cells are separated from the complex medium. the challenge is magnified in vi ... | 2011 | 22166686 |
| 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 ... | 2011 | 22077160 |
| cross-pollination of nontransgenic corn ears with transgenic bt corn: efficacy against lepidopteran pests and implications for resistance management. | the efficacy of nontransgenic sweet corn, zea mays l., hybrids cross-pollinated by bacillus thuringiensis (bt) sweet corn hybrids expressing cry1ab toxin was evaluated in both field and laboratory studies in minnesota in 2000. non-bt and bt hybrids (maternal plants) were cross-pollinated with pollen from both non-bt and bt hybrids (paternal plants) to create four crosses. subsequent crosses were evaluated for efficacy in the field against european corn borer, ostrinia nubilalis (hübner), and cor ... | 2011 | 22066174 |
| herbivore-induced changes in tomato (solanum lycopersicum) primary metabolism: a whole plant perspective. | induced changes in primary metabolism are important plant responses to herbivory, providing energy and metabolic precursors for defense compounds. metabolic shifts also can lead to reallocation of leaf resources to storage tissues, thus increasing a plant's tolerance. we characterized whole-plant metabolic responses of tomato (solanum lycopersicum) 24 h after leaf herbivory by two caterpillars (the generalist helicoverpa zea and the specialist manduca sexta) by using gc-ms. we measured 56 primar ... | 2011 | 22161151 |
| a larval specific lipoprotein: purification and characterization of a blue chromoprotein from heliothis zea. | the green color of the hemolymph of last instar larvae of the corn earworm, heliothis zea (boddie), is caused by the appearance of a blue chromoprotein. this protein (mr approximately 560,000) is composed of 4 subunits (mr approximately 150,000). it contains 8.4% lipid and has an equilibrium density of 1.26 g/ml. this protein is absent during all early larval stages, in pupae and in adult animals, but is a major hemolymph protein in 5th instar larvae. although its physiological function remains ... | 2013 | 3947340 |
| transposable elements are enriched within or in close proximity to xenobiotic-metabolizing cytochrome p450 genes. | transposons, i.e. transposable elements (tes), are the major internal spontaneous mutation agents for the variability of eukaryotic genomes. to address the general issue of whether transposons mediate genomic changes in environment-adaptation genes, we scanned two alleles per each of the six xenobiotic-metabolizing helicoverpa zea cytochrome p450 loci, including cyp6b8, cyp6b27, cyp321a1, cyp321a2, cyp9a12v3 and cyp9a14, for the presence of transposon insertions by genome walking and sequence an ... | 2007 | 17381843 |
| atp hydrolyzing salivary enzymes of caterpillars suppress plant defenses. | the oral secretions of herbivores are important recognition cues that can be used by plants to mediate induced defenses. in this study, a degradation of adenosine-5'-triphosphate (atp) in tomato leaves was detected after treatment with helicoverpa zea saliva. correspondingly, a high level of atpase activity in saliva was detected and three atp hydrolyzing enzymes: apyrase, atp synthase and atpase 13a1 were identified in salivary glands. to determine the functions of these proteins in mediating d ... | 2012 | 22848670 |
| 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 ... | 2012 | 22558369 |
| plant dependence on rhizobia for nitrogen influences induced plant defenses and herbivore performance. | symbiotic rhizobia induce many changes in legumes that could affect aboveground interactions with herbivores. we explored how changing the intensity of bradyrhizobium japonicum, as modulated by soil nitrogen (n) levels, influenced the interaction between soybean (glycine max) and herbivores of different feeding guilds. when we employed a range of fertilizer applications to manipulate soil n, plants primarily dependent on rhizobia for n exhibited increased root nodulation and higher levels of fol ... | 2014 | 24451132 |
| analysis of the genome of the sexually transmitted insect virus helicoverpa zea nudivirus 2. | the sexually transmitted insect virus helicoverpa zea nudivirus 2 (hznv-2) was determined to have a circular double-stranded dna genome of 231,621 bp coding for an estimated 113 open reading frames (orfs). hznv-2 is most closely related to the nudiviruses, a sister group of the insect baculoviruses. several putative orfs that share homology with the baculovirus core genes were identified in the viral genome. however, hznv-2 lacks several key genetic features of baculoviruses including the late t ... | 2012 | 22355451 |
| natural history and intragenomic dynamics of the transib transposon hztransib in the cotton bollworm helicoverpa zea. | hztransib, recently identified from helicoverpa zea, represents the first intact and transcriptionally active transib element. its open reading frame was detected in helicoverpa armigera, from which h. zea evolved, and in helicoverpa assulta, the common ancestor of h. zea and h. armigera, but its remaining parts were found only in h. armigera. thirty-nine hztransib insertion sites, all of which are polymorphic, were detected from eight populations of h. zea. out of the 39 insertion sites, 35 wer ... | 2010 | 21166910 |
| molecular cloning and functional characterization of the diapause hormone receptor in the corn earworm helicoverpa zea. | the diapause hormone (dh) in the heliothine moth has shown its activity in termination of pupal diapause, while the orthology in the silkworm is known to induce embryonic diapause. in the current study, we cloned the diapause hormone receptor from the corn earworm helicoverpa zea (hzdhr) and tested its ligand specificities in a heterologous reporter system. hzdhr was expressed in chinese hamster ovary (cho) cells, which were co-transfected with the aequorin reporter, and was used to measure the ... | 2013 | 24257143 |
| bioprospecting for secondary metabolites in the entomopathogenic bacterium photorhabdus luminescens subsp. sonorensis. | crude extracts of in vitro and in vivo cultures of two strains of photorhabdus l. sonorensis (enterobacteriaceae) were analyzed by tlc, hplc-uv and lc-ms. nine unique compounds with mass/charge ratios (m/z) ranging from 331.3 to 713.5 were found in ms analyses. bioactivity of extracts was assessed on a selection of plant pathogens/pests and non-target species. caborca strain extracts showed the highest activity against helicoverpa zea (lepidoptera: noctuidae) neonates at all concentrations teste ... | 2016 | 27702563 |
| expression of a wolf spider toxin in tobacco inhibits the growth of microbes and insects. | lycotoxin i, from the wolf spider (lycosa carolinensis), is an amphipathic pore-forming peptide that has antimicrobial and anti-insect activity. constitutive expression of a lycotoxin i modified for oral toxicity to insects in tobacco (nicotiana tabacum) conferred significantly enhanced resistance to larvae of the corn earworm (helicoverpa zea) and cigarette beetle (lasioderma serricorne). gene expression levels of modified lycotoxin i were negatively correlated to the survival of corn earworm l ... | 2014 | 24770871 |
| field-evolved resistance in corn earworm to cry proteins expressed by transgenic sweet corn. | transgenic corn engineered with genes expressing insecticidal toxins from the bacterium bacillus thuringiensis (berliner) (bt) are now a major tool in insect pest management. with its widespread use, insect resistance is a major threat to the sustainability of the bt transgenic technology. for all bt corn expressing cry toxins, the high dose requirement for resistance management is not achieved for corn earworm, helicoverpa zea (boddie), which is more tolerant to the bt toxins. | 2016 | 28036388 |
| impact of lepidoptera (crambidae, noctuidae, and pyralidae) pests on corn containing pyramided bt traits and a blended refuge in the southern united states. | blended refuge for transgenic plants expressing bacillus thuringiensis (bt) toxins has been approved in the northern united states as a resistance management strategy alternative to a structured refuge. a three-year study (2012-2014) was conducted with 54 trials across nine states in the southern united states to evaluate plant injury from lepidopteran pests of corn and yield in a corn hybrid expressing cry1f × cry1ab × vip3aa20 (pioneer brand optimum leptra) planted as a pure stand and in refug ... | 2016 | 27329627 |
| balancing bt toxin avoidance and nutrient intake by helicoverpa zea (lepidoptera: noctuidae) larvae. | to evaluate how the cry1ac bacillus thuringiensis (bt) toxin and the ratio of dietary protein to carbohydrate (p:c) independently and jointly affect helicoverpa zea (boddie) larval feeding performance and behavior, we conducted no-choice and binary choice experiments using chemically defined diets. we tested two related strains of this polyphagous pest: a strain selected for resistance to cry1ac in the laboratory (ga-r), and its field-derived parent strain (ga). in no-choice tests, feeding perfo ... | 2015 | 26470372 |
| intraear compensation of field corn, zea mays, from simulated and naturally occurring injury by ear-feeding larvae. | ear-feeding larvae, such as corn earworm, helicoverpa zea boddie (lepidoptera: noctuidae), can be important insect pests of field corn, zea mays l., by feeding on kernels. recently introduced, stacked bacillus thuringiensis (bt) traits provide improved protection from ear-feeding larvae. thus, our objective was to evaluate how injury to kernels in the ear tip might affect yield when this injury was inflicted at the blister and milk stages. in 2010, simulated corn earworm injury reduced total ker ... | 2015 | 26470235 |
| lepidoptera (crambidae, noctuidae, and pyralidae) injury to corn containing single and pyramided bt traits, and blended or block refuge, in the southern united states. | fall armyworm, spodoptera frugiperda (j. e. smith) (lepidoptera: noctuidae); corn earworm, helicoverpa zea boddie (lepidoptera: noctuidae); southwestern corn borer, diatraea grandiosella dyar (lepidoptera: crambidae); sugarcane borer, diatraea saccharalis f. (lepidoptera: crambidae); and lesser cornstalk borer, elasmopalpus lignosellus zeller (lepidoptera: pyralidae), are lepidopteran pests of corn, zea mays l., in the southern united states. blended refuge for transgenic plants expressing the i ... | 2015 | 26470116 |
| a challenge for the seed mixture refuge strategy in bt maize: impact of cross-pollination on an ear-feeding pest, corn earworm. | to counter the threat of insect resistance, bacillus thuringiensis (bt) maize growers in the u.s. are required to plant structured non-bt maize refuges. concerns with refuge compliance led to the introduction of seed mixtures, also called rib (refuge-in-the-bag), as an alternative approach for implementing refuge for bt maize products in the u.s. maize belt. a major concern in rib is cross-pollination of maize hybrids that can cause bt proteins to be present in refuge maize kernels and negativel ... | 2014 | 25409442 |
| a comparison of bt transgene, hybrid background, water stress, and insect stress effects on corn leaf and ear injury and subsequent yield. | experimentally manipulated water and insect stresses were applied to field-grown corn with different bacillus thuringiensis (bt) transgenes and no bt transgenes, and different nontransgenic hybrid backgrounds (2011 and 2012, corpus christi, tx). differences in leaf injury, ear injury, and yield were detected among experimental factors and their interactions. under high and low water stress, injury from noctuid larvae (lepidoptera: noctuidae) on leaves during vegetative growth (primarily from fal ... | 2014 | 24780114 |
| managing the sugarcane borer, diatraea saccharalis, and corn earworm, helicoverpa zea, using bt corn and insecticide treatments. | the sugarcane borer, diatraea saccharalis (fabricius) (lepidoptera: crambidae) and the corn earworm, helicoverpa zea (boddie) (lepidoptera: noctuidae), are important pests of corn in brazil and have not been successfully managed, because of the difficulty of managing them with pesticides. the objective of this study was to evaluate the effect of bt corn mon810, transformed with a gene from bacillus thuringiensis berliner (bacillales: bacillaceae) insecticide seed treatment, and foliar insecticid ... | 2013 | 24735131 |
| efficacy of pyramided bt proteins cry1f, cry1a.105, and cry2ab2 expressed in smartstax corn hybrids against lepidopteran insect pests in the northern united states. | commercial field corn (zea mays l.) hybrids transformed to express some or all of the lepidopteran insect-resistant traits present in smartstax corn hybrids were evaluated for insecticidal efficacy against a wide range oflepidopteran corn pests common to the northern united states, during 2008 to 2011 at locations in 15 states. smartstax hybrids contain a pyramid of two bacillus thuringiensis (bt) derived events for lepidopteran control: event tc1507 expressing cry1f protein and mon 89034 expres ... | 2014 | 24665726 |
| risk assessment for helicoverpa zea (lepidoptera: noctuidae) resistance on dual-gene versus single-gene corn. | recent environmental protection agency (epa) decisions regarding resistance management in bt-cropping systems have prompted concern in some experts that dual-gene bt-corn (cryla.105 and cry2ab2 toxins) may result in more rapid selection for resistance in helicoverpa zea (boddie) than single-gene bacillus thuringiensis (bt)-corn (crylab toxin). the concern is that bt-toxin longevity could be significantly reduced with recent adoption of a natural refuge for dual-gene bt-cotton (crylac and cry2ab2 ... | 2013 | 23448055 |
| 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 ... | 2012 | 23156183 |
| identification of a g protein-coupled receptor for pheromone biosynthesis activating neuropeptide from pheromone glands of the moth helicoverpa zea. | pheromone biosynthesis-activating neuropeptide (pban), a peptide produced by the subesophageal ganglion, is used by a variety of moths to regulate pheromone production. pban acts directly on pheromone gland cells by using calcium and camp as second messengers. we have identified a gene encoding a g protein-coupled receptor (gpcr) from pheromone glands of the female moth helicoverpa zea. the gene was identified based on sequence identity to a group of gpcrs from drosophila that are homologous to ... | 2003 | 12888624 |
| enhanced pest resistance of maize leaves expressing monocot crop plant-derived ribosome-inactivating protein and agglutinin. | although many insect resistance genes have been identified, the number of studies examining their effects in combination using transgenic systems is limited. this study introduced a construct into maize containing the coding sequence for maize ribosome-inactivating protein (mrip) and wheat germ agglutinin (wga). many transformants produced both the mrip and wga in leaves. mature leaves expressing higher levels of these two proteins were more resistant to feeding by first-instar larvae of fall ar ... | 2012 | 23078237 |
| providence virus (family: carmotetraviridae) replicates vrna in association with the golgi apparatus and secretory vesicles. | providence virus (prv) is the sole member of the family carmotetraviridae (formerly tetraviridae) sharing the characteristic t=4 capsid architecture with other tetravirus families. despite significant structural similarities, prv differs from other tetraviruses in terms of genome organization, non-structural protein sequence and regulation of gene expression. in addition, it is the only tetravirus that infects tissue culture cells. previous studies showed that in persistently infected helicoverp ... | 2013 | 23343628 |
| genome sequence and organization analysis of heliothis virescens ascovirus 3f isolated from a helicoverpa zea larva. | the complete genome sequence of heliothis virescens ascovirus 3f (hvav-3f) was obtained. the hvav-3f genome has a circular genome of 198,157bp with a g+c content of 46.0%, and encodes 190 open reading frames (orfs) longer than 69 amino acids. two major homologous regions (hrs) and 29 'baculovirus repeat orfs' (bro) were found in the genome. blast analyses revealed that three hvav-3f genes were homologous to that of lepidopteran insects. nine orfs were unique to hvav-3f, in which two orfs showed ... | 2014 | 25149038 |
| specificity of induced resistance in the tomato, lycopersicon esculentum. | specificity in the induced responses of tomato foliage to arthropod herbivores was investigated. we distinguished between two aspects of specificity: specificity of effect (the range of organisms affected by a given induced response), and specificity of elicitation (ability of the plant to generate distinct chemical responses to different damage types). specificity of effect was investigated by examining the effect of restricted feeding by helicoverpa zea on the resistance of tomato plants to an ... | 1997 | 28307296 |
| evaluation of corn germplasm lines for multiple ear-colonizing insect and disease resistance. | ear-colonizing insects and diseases that reduce yield and impose health threats by mycotoxin contaminations in the grain, are critical impediments for corn (zea mays l.) production in the southern united states. ten germplasm lines from the germplasm enhancement of maize (gem) program in ames, ia, and raleigh, nc, and 10 lines (derived from gem germplasm) from the texas agricultural experiment station in lubbock, tx, were examined in 2007 and 2008 with local resistant and susceptible controls. f ... | 2012 | 22928329 |
| the kinin peptide family in invertebrates. | kinins comprise a family of peptides that were first found in the central nervous system of insects and recently also in mollusks and crustaceans. after the isolation of the first members of the kinin family, the leukokinins from leucophaea maderae, leukokinin-related peptides were found in the cricket acheta domesticus and the locust locusta migratoria, all through their ability to induce leucophaea maderae hindgut contraction. subsequently, kinins were found in the mosquitoes culex salinarius ... | 1999 | 10676463 |
| minimum rates of insecticides on soybeans: mexican bean beetle, green clover worm, corn earworm and velvetbean caterpillar. | | 2016 | 4857577 |
| study of the pest community of velvetleaf (abutilon theophrasti medic.). | velvetleaf (abutilon theophrasti medicus 1787) is one of the most economically threatening weed plant in hungary. researching biological control against it, and identifying a possible and effective biocontrol agent is an important challenge, as chemical control is difficult and expensive, and there is an increasing claim to practice slight plant protection. entomological studies were made in several parts of the world, for evaluating the species, occuring in velvetleaf, but none of these kind of ... | 2011 | 22696962 |
| changes in trace metals in hemolymph of baculovirus-infected noctuid larvae. | we studied how biologically relevant trace metals (i.e., micronutrients) in the hemolymph of larval heliothis virescens and helicoverpa zea (lepidoptera: noctuidae) changed in response to per os baculovirus infection, larval development, and injection of heat-killed bacteria. concentrations of hemolymph co, cr, cu, fe, mg, mn, mo, ni, and zn were measured using inductively coupled plasma-mass spectrometry. h. virescens larvae exhibited greater fluctuations in hemolymph trace metal levels in resp ... | 2011 | 22083423 |
| susceptibility of helicoverpa zea and heliothis virescens (lepidoptera: noctuidae) to vip3a insecticidal protein expressed in vipcot™ cotton. | susceptibility of laboratory and field colonies of helicoverpa zea (boddie) and heliothis virescens f. to vip3a insecticidal protein was studied in diet incorporation and diet overlay assays from 2004 to 2008. responses of field populations were compared to paired responses of university of arkansas laboratory susceptible h. zea (labza) and h. virescens (labvr) colonies. after 7d of exposure, observations were made on number of dead larvae (m) and the number of larvae alive but remaining as firs ... | 2011 | 21767545 |