Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| interactions of alternate hosts, postemergence grass control, and rootworm-resistant transgenic corn on western corn rootworm (coleoptera: chrysomelidae) damage and adult emergence. | field studies were conducted in 2003 and 2004 to determine the effects of grassy weeds, postemergence grass control, transgenic rootworm-resistant corn, zea mays l., expressing the cry3bb1 endotoxin and glyphosate herbicide tolerance (bt corn), and the interactions of these factors on western corn rootworm, diabrotica virgifera virgifera leconte, damage and adult emergence. three insect management tactics (bt corn, its nontransgenic isoline, and isoline plus tefluthrin) were evaluated with two w ... | 2007 | 17461083 |
| a global approach to resistance monitoring. | transgenic crops producing insecticidal toxins from the bacterium bacillus thuringiensis (bt) have been grown in many parts of the world since 1996. in the united states, the environmental protection agency (epa) has required that industry submit insect resistance management (irm) plans for each bt corn and cotton product commercialized. a coalition of stakeholders including the epa, usda, academic scientists, industry, and grower organizations have cooperated in developing specific irm strategi ... | 2007 | 17467005 |
| genetic diversity in laboratory colonies of western corn rootworm (coleoptera: chrysomelidae), including a nondiapause colony. | laboratory-reared western corn rootworms, diabrotica virgifera virgifera, from colonies maintained at the north central agricultural research laboratory (ncarl) in brookings, sd, are used extensively by many researchers in studies of the biology, ecology, behavior, and genetics of this major insect pest. a nondiapause colony developed through artificial selection in the early 1970s is particularly attractive for many studies because its generation time is much shorter than that of typical diapau ... | 2007 | 17540076 |
| toxicity of chromobacterium subtsugae to southern green stink bug (heteroptera: pentatomidae) and corn rootworm (coleoptera: chrysomelidae). | diabrotica spp. (coleoptera: chrysomelidae) beetles and southern green stink bugs, nezara viridula (l.) (heteroptera: pentatomidae), are pests on corn, zea mays l., and soybean, glycine max (l.) merr., as well as on cucurbits. control of these insects has depended on chemicals. an alternative to chemical control is the use of biologicals. use of bacteria, fungi, viruses, pheromones, and metabolites to control these insects can potentially improve resistance management and reduce pesticide use. o ... | 2007 | 17598525 |
| insect pest densities across site-specific management zones of irrigated corn in northeastern colorado. | the ability to manage insect pests in a site-specific manner is hindered by the costs and time required to describe pest densities and distributions. the purpose of this study was to determine whether insect pest distributions are related to site-specific management zones (ssmzs). site-specific management zones, as described in this study, delineate fields into three zones of similar yield potential: high, medium, and low productivity. if insect densities vary across ssmzs, it is possible that m ... | 2007 | 17598539 |
| a novel cadherin-like gene from western corn rootworm, diabrotica virgifera virgifera (coleoptera: chrysomelidae), larval midgut tissue. | a cadherin-like gene associated with larval midgut tissues was cloned from western corn rootworm (diabrotica virgifera virgifera: coleoptera), an economically important agricultural pest in north america and europe and the primary target pest species for corn hybrids expressing cry3 toxins from bacillus thuringiensis (bt). the full-length cdna (5371 bp in length) encodes an open reading frame for a 1688 amino acid polypeptide. the putative protein has similar architecture to cadherin-like protei ... | 2007 | 17725800 |
| 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 ... | 2007 | 17845293 |
| population dynamics of a western corn rootworm (coleoptera: chrysomelidae) variant in east central illinois commercial maize and soybean fields. | three on-farm sites in iroquois county, il, each containing an adjacent 16.2-ha commercial production maize, zea mays l., and soybean, glycine max (l.) merr., field, were monitored for western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), adults from june through september 1999-2001. mean captures of d. v. virgifera adults as measured with pherocon am yellow sticky traps were significantly greater in maize than in soybean. overall mean numbers of d. v. virgif ... | 2007 | 17849858 |
| effectiveness of corn rootworm (coleoptera: chrysomelidae) areawide pest management in south dakota. | diabrotica barberi smith & lawrence and diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae) are serious pests of maize, zea mays l. to reduce the amount of toxicants released into the environment, the agricultural research service implemented a 5-yr (1997-2001) areawide pest management program in five geographic locations, including one in south dakota. the objective was to use integrated pest management tactics to suppress adult diabrotica populations over a broad geographic area ... | 2007 | 17972631 |
| control of coleopteran insect pests through rna interference. | commercial biotechnology solutions for controlling lepidopteran and coleopteran insect pests on crops depend on the expression of bacillus thuringiensis insecticidal proteins, most of which permeabilize the membranes of gut epithelial cells of susceptible insects. however, insect control strategies involving a different mode of action would be valuable for managing the emergence of insect resistance. toward this end, we demonstrate that ingestion of double-stranded (ds)rnas supplied in an artifi ... | 2007 | 17982443 |
| utility of est-derived ssrs as population genetics markers in a beetle. | microsatellite, or simple sequence repeat (ssr), loci can be identified by mining expressed sequence tag (est) databases, and where these are available, marker development time and expense can be decreased considerably over conventional strategies of probing the entire genome. however, it is unclear whether they provide information on population structure similar to that generated by anonymous genomic ssrs. we performed comparative population genetic analyses between est-derived ssrs (est-ssrs) ... | 2008 | 18222933 |
| 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 ... | 2008 | 18296628 |
| anthropogenic increase in carbon dioxide compromises plant defense against invasive insects. | elevated levels of atmospheric carbon dioxide (co2), a consequence of anthropogenic global change, can profoundly affect the interactions between crop plants and insect pests and may promote yet another form of global change: the rapid establishment of invasive species. elevated co2 increased the susceptibility of soybean plants grown under field conditions to the invasive japanese beetle (popillia japonica) and to a variant of western corn rootworm (diabrotica virgifera virgifera) resistant to ... | 2008 | 18375762 |
| diabrotica virgifera virgifera leconte: inconspicuous leaf beetle--formidable challenges to agriculture. | in the universe of entomology with its close to one million described and an estimated ten million undescribed species, diabrotica virgifera virgifera leconte (coleoptera: chrysometidae), the western corn rootworm (wcr), is one of the economically most important pests. it causes annual treatment costs and damages of a billion dollars in the us (metcalf 1986). similar costs are predicted for europe which the beetle invaded 15 years ago. due to lack of natural enemies it is now expanding its terri ... | 2007 | 18399421 |
| a core set of microsatellite markers for western corn rootworm (coleoptera: chrysomelidae) population genetics studies. | interest in the ecological and population genetics of the western corn rootworm, diabrotica virgifera virgifera leconte, has grown rapidly in the last few years in north america and europe. this interest is a result of a number of converging issues related to the increasing difficulty in managing this pest and the need to characterize and understand gene flow in the context of insect resistance management. one of the key components needed for successful population genetics studies is the availab ... | 2008 | 18419899 |
| belowground chemical signaling in maize: when simplicity rhymes with efficiency. | maize roots respond to feeding by larvae of the beetle diabrotica virgifera virgifera by releasing (e)-beta-caryophyllene. this sesquiterpene, which is not found in healthy maize roots, attracts the entomopathogenic nematode heterorhabditis megidis. in sharp contrast to the emission of virtually only this single compound by damaged roots, maize leaves emit a blend of numerous volatile organic compounds in response to herbivory. to try to explain this difference between roots and leaves, we studi ... | 2008 | 18443880 |
| identification of feeding stimulants in corn roots for western corn rootworm (coleoptera: chrysomelidae) larvae. | using a bioassay-driven approach, we have isolated and identified a blend of compounds from the roots of germinating corn, zea mays l., that serve as feeding stimulants for neonate western corn rootworm larvae, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae). the active blend is a combination of simple sugars (30:4:4 mg/ml glucose:fructose:sucrose in the corn root) plus at least one of the free fatty acids in germinating corn roots (2:5 mg/ml oleic acid:linoleic acid in the co ... | 2008 | 18459397 |
| increased expression of a cgmp-dependent protein kinase in rotation-adapted western corn rootworm (diabrotica virgifera virgifera l.). | a new 'variant' behavior in western corn rootworm (wcr) has resulted in egg-laying into non-cornfields, compared to 'normal' deposition of eggs in cornfields, allowing these insects to circumvent crop rotation. no morphological or genetic characteristics have been defined to differentiate between the normal and variant biotypes. cyclic gmp-dependent protein kinases (pkg) have been implicated in the regulation of behaviors in vertebrates, insects, and nematodes, including foraging behavior in dro ... | 2008 | 18549955 |
| examining cuphea as a potential host for western corn rootworm (coleoptera: chrysomelidae): larval development. | in previous crop rotation research, adult emergence traps placed in plots planted to cuphea psr-23 (a selected cross of cuphea viscosissma jacq. and cuphea lanceolata ait.) caught high numbers of adult western corn rootworms, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), suggesting that larvae may have completed development on this broadleaf plant. because of this observation, a series of greenhouse and field experiments were conducted to test the hypothesis that cuphea cou ... | 2008 | 18613580 |
| invasion of europe by the western corn rootworm, diabrotica virgifera virgifera: multiple transatlantic introductions with various reductions of genetic diversity. | the early stages of invasion involve demographic bottlenecks that may result in lower genetic variation in introduced populations as compared to source population/s. low genetic variability may decrease the adaptive potential of such populations in their new environments. previous population genetic studies of invasive species have reported varying levels of losses of genetic variability in comparisons of source and invasive populations. however, intraspecific comparisons are required to assess ... | 2008 | 18662220 |
| papain-like cysteine proteases: key players at molecular battlefields employed by both plants and their invaders. | papain-like cysteine proteases (plcps) play crucial roles in plant-pathogen/pest interactions. during these parasitic interactions, plcps act on non-self substrates, provoking the selection of counteracting inhibitors and other means to evade proteolysis. we review examples of plcps acting on molecular battlefields in the extracellular space, plant cytoplasm and herbivore gut. examples are maize mir1 (maize inbred resistance 1), tomato rcr3 (required for cladosporium resistance-3), pseudomonas a ... | 2008 | 18705889 |
| the nutritive value of dying maize and setaria faberi roots for western corn rootworm (coleoptera: chrysomelidae) development. | the timing that dying root tissues of setaria faberi r.a.w. herrm. and maize, zea mays l., no longer support growth and development of neonate and second-instar western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), larvae was evaluated to enhance our understanding of the basic ecology of this pest. three separate greenhouse experiments were conducted. in the first experiment, glyphosate was used to kill s. faberi. in the second experiment, glyphosate was used ... | 2008 | 18950036 |
| physiological time model for predicting adult emergence of western corn rootworm (coleoptera: chrysomelidae) in the texas high plains. | field observations at three locations in the texas high plains were used to develop and validate a degree-day phenology model to predict the onset and proportional emergence of adult diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae) adults. climatic data from the texas high plains potential evapotranspiration network were used with records of cumulative proportional adult emergence to determine the functional lower developmental temperature, optimum starting date, and the sum of ... | 2008 | 18950040 |
| increased survival of western corn rootworm on transgenic corn within three generations of on-plant greenhouse selection. | to delay evolution of insect resistance to transgenic crops producing bacillus thuringiensis (bt) toxins, nearby "refuges" of host plants not producing bt toxins are required in many regions. such refuges are expected to be most effective in slowing resistance when the toxin concentration in bt crops is high enough to kill all or nearly all insects heterozygous for resistance. however, bt corn, zea mays, introduced recently does not meet this "high-dose" criterion for control of western corn roo ... | 2008 | 19047626 |
| molecular level lignin patterns of genetically modified bt-maize mon88017 and three conventional varieties using tetramethylammonium hydroxide (tmah)-induced thermochemolysis. | bt-maize mon88017, its near-isogenic line dkc5143, and the two conventional varieties dk315 and benicia were subjected to tetramethylammonium hydroxide (tmah)-induced thermochemolysis to reveal molecular level lignin patterns. mon88017 is genetically modified to express the cry3bb1 protein aimed at the western corn rootworm diabrotica virgifera virgifera, a serious threat for european maize production. the results indicated that roots of the bt-maize were characterized by a slightly enhanced tot ... | 2008 | 19053395 |
| adaptation and invasiveness of western corn rootworm: intensifying research on a worsening pest. | the western corn rootworm, diabrotica virgifera virgifera leconte, is an established insect pest of maize (zea mays l.) in north america. the rotation of maize with another crop, principally soybeans, glycine max (l.), was the primary management strategy utilized by north american producers and remained highly effective until the mid-1990s. in 1995, widespread and severe root injury occurred in east-central illinois and northern indiana maize fields that had been annually rotated with soybeans o ... | 2009 | 19067634 |
| maize phenology affects establishment, damage, and development of the western corn rootworm (coleoptera: chrysomelidae). | the effects of maize (zea mays l.) phenology on establishment and adult emergence of the western corn rootworm (diabrotica virgifera virgifera leconte) and plant damage to maize was evaluated in field trials in 2001 and 2002 and in the greenhouse. although neonate western corn rootworm larvae were able to initially establish on maize roots during anthesis and early reproductive stages, these older roots were apparently unsuitable for complete western corn rootworm larval development. the number ... | 2008 | 19161700 |
| experiences with population dynamics of diabrotica virgifera virgifera leconte in the swiss canton of ticino up to 2007. | the western corn rootworm (wcr) diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae) is a vexing alien invasive insect pest. it occupies the attention of entomologists in most countries of europe and beyond. in spite of numerous research advances (e.g., diabrotica symposium at engelberg, switzerland 2004) its behavior is still incompletely understood and cannot be predicted for a specific growing season with any degree of certainty. nonetheless, by comparing several years in sequen ... | 2008 | 19226781 |
| the western corn rootworm (diabrotica virgifera virgifera) and its first appearance in germany 2007. | diabrotica v. virgifera (wcr) is one of the most successful invasive insect species and owes this success to its close association with mankind, to worldwide trade and commerce connections, and to widely practiced, monoculturally oriented production patterns which are characteristic for contemporary agriculture in several parts of the world. without a drastic change in attitudes and approaches of a globalizing agriculture, wcr will in the foreseeable future have invaded all maize growing areas. ... | 2008 | 19226788 |
| monitoring diabrotica v. virgifera (col.: chrysomelidae) in southeastern slovenia: increasing population trend and host spectrum expansion. | ever since the western corn rootworm (wcr) (diabrotica virgifera virgifera), an alien invasive species from north america, has been introduced into europe on at least 3 separate occasions, it spread within 15 years over the entire area of south-eastern and central europe (except denmark). until quite recently, zea mays l. was the only known host plant whereas in north america wcr also attacks members of the plant family cucurbitaceae. in august of 2006, we were able to validate these findings al ... | 2008 | 19226789 |
| natural enemies in control of invasive species diabrotica virgifera virgifera from maize crops. | the invasive diabrotico virgifera virgifera le conte (western corn rootworm) species has become a very important pest of maize growing areas from europe. incidence of this pest in europe and romania attract the specialist's attention and european organisms regarding substantial changes which save the yield. current trends in control regard the using natural enemies' because non-pollutants effects. in this way it follows protection of useful scale from agroecosystems and their exploitation in con ... | 2008 | 19226790 |
| parasitism of western corn rootworm larvae and pupae by steinernema carpocapsae. | virulence and development of the insect-parasitic nematode, steinernema carpocapsae (weiser) (mexican strain), were evaluated for the immature stages of the western corn rootworm, diabrotica virgifera virgifera leconte. third instar rootworm larvae were five times more susceptible to nematode infection than second instar larvae and 75 times more susceptible than first instar larvae and pupae, based on laboratory bioassays. rootworm eggs were not susceptible. nematode development was observed in ... | 1995 | 19277256 |
| effects of pesta-pelletized steinernema carpocapsae (all) on western corn rootworms and colorado potato beetles. | pesta-pelletized steinernema carpocapsae (all) nematodes were used in soil treatments in the greenhouse against larvae of western corn rootworm and prepupae of colorado potato beetle. the pesta-pellets delivered 100,000 living nematodes/g. infective-stage nematodes and their associated bacteria survived the pesta-pellet process, emerged from the pellets in large numbers in the soil, and reduced adult emergence of both pest insects by more than 90%. | 1994 | 19279889 |
| protease activities in the midgut of western corn rootworm (diabrotica virgifera virgifera leconte). | the western corn rootworm is one of the most economically important pests in corn. one possibility for controlling this pest is the cultivation of transgenic corn expressing bacillus thuringiensis (bt) toxins, such as cry3a, cry34ab1/cry35ab1, and cry3bb1. however, widespread cultivation of the resulting bt corn may result in the development of resistant pest populations. the bt toxins are processed by proteases in the midgut of susceptible insects. thus, protease activity studies were conducted ... | 2009 | 19320044 |
| acute and repeated dose (28 day) mouse oral toxicology studies with cry34ab1 and cry35ab1 bt proteins used in coleopteran resistant das-59122-7 corn. | expression of the cry34ab1 and cry35ab1 proteins from bacillus thuringiensis (bt) berliner strain ps149b1 in genetically modified maize (event das-59122-7) protects the crop from damage due to feeding by diabrotica larvae including the western corn rootworm (diabrotica virgifera virgifera). as part of the safety assessment of this maize, mammalian toxicology studies were conducted with heterologously produced cry34ab1 and cry35ab1 proteins. no evidence of acute toxicity was observed in mice foll ... | 2009 | 19328831 |
| enhancement of bacillus thuringiensis cry3aa and cry3bb toxicities to coleopteran larvae by a toxin-binding fragment of an insect cadherin. | the cry3aa and cry3bb insecticidal proteins of bacillus thuringiensis are used in biopesticides and transgenic crops to control larvae of leaf-feeding beetles and rootworms. cadherins localized in the midgut epithelium are identified as receptors for cry toxins in lepidopteran and dipteran larvae. previously, we discovered that a peptide of a toxin-binding cadherin expressed in escherichia coli functions as a synergist for cry1a toxicity against lepidopteran larvae and cry4 toxicity against dipt ... | 2009 | 19329664 |
| pyrosequencing of the midgut transcriptome of the poplar leaf beetle chrysomela tremulae reveals new gene families in coleoptera. | the insect midgut is the primary target site for bt-derived insecticides and bt alternatives. however, despite extensive recent study, the precise role and nature of different bt receptors remains a subject of considerable debate. this problem is fuelled by a lack of understanding of the genes expressed in the insect midgut and their physiological roles. the poplar leaf beetle, chrysomela tremulae, is an important model for understanding the mode of action of, and resistance to, coleopteran-spec ... | 2009 | 19364528 |
| susceptibility of diabrotica virgifera virgifera (coleoptera: chrysomelidae) to the entomopathogenic fungus metarhizium anisopliae when feeding on bacillus thuringiensis cry3bb1-expressing maize. | genetically engineered maize producing the insecticidal protein cry3bb1 from bacillus thuringiensis (bt maize) is protected against corn rootworms (diabrotica spp.), which are serious maize pests in north america and europe. the aim of the present study was to investigate the interaction of bt maize (event mon88017) and the entomopathogenic fungus metarhizium anisopliae for controlling the western corn rootworm, diabrotica virgifera virgifera. exposure to cry3bb1 expressed in bt maize seedlings ... | 2009 | 19376921 |
| 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 ... | 2009 | 19392694 |
| localized search cues in corn roots for western corn rootworm (coleoptera: chrysomelidae) larvae. | cues that elicit a characteristic localized search behavior by neonate larvae of the western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), were extracted from living corn, zea mays l., roots with acetone. larvae were exposed to corn roots or to an acetone extract of corn roots and then transferred into a bioassay arena where their movements were tracked and recorded. after a 5-min exposure to live corn roots, larvae produced highly convoluted tracks that were ... | 2009 | 19449635 |
| comparative performance of single nucleotide polymorphism and microsatellite markers for population genetic analysis. | microsatellite loci are standard genetic markers for population genetic analysis, whereas single nucleotide polymorphisms (snps) are more recent tools that require assessment of neutrality and appropriate use in population genetics. twelve snp markers were used to describe the genetic structure of diabrotica virgifera virgifera (leconte; coleoptera: chrysomelidae) in the united states of america and revealed a high mean observed heterozygosity (0.40 +/- 0.059) and low global f(st) (0.029). pairw ... | 2009 | 19525239 |
| conventional screening overlooks resistance sources: rootworm damage of diverse inbred lines and their b73 hybrids is unrelated. | the western corn rootworm, diabrotica virgifera virgifera (leconte), is a major pest of maize, zea mays l., in the united states and europe, and it is likely to increase in importance as a trend toward increased nonrotated maize favors larger rootworm populations. options for rootworm management in nonrotated maize in europe and in nontransgenic "refuge" areas in countries that permit transgenic maize are limited to insecticides. development of additional options for growers would be helpful. sc ... | 2009 | 19610453 |
| inferring introduction routes of invasive species using approximate bayesian computation on microsatellite data. | determining the routes of introduction provides not only information about the history of an invasion process, but also information about the origin and construction of the genetic composition of the invading population. it remains difficult, however, to infer introduction routes from molecular data because of a lack of appropriate methods. we evaluate here the use of an approximate bayesian computation (abc) method for estimating the probabilities of introduction routes of invasive populations ... | 2010 | 19654609 |
| impact of mon863 transgenic roots is equivalent on western corn rootworm larvae for a wide range of maize phenologies. | the effects of maize, zea mays l., phenology on establishment, damage, and adult emergence of the western corn rootworm, diabrotica virgifera virgifera leconte, on mon863 transgenic maize expressing the cry3bb1 protein and its isoline was evaluated in field trials in 2002 and 2003. as expected, plant damage, western corn rootworm larval recovery, and adult emergence were significantly lower on mon863 than isoline maize. the average weight of larvae and adults recovered from mon863 and isoline ma ... | 2009 | 19736775 |
| effectiveness of glues used for harmonic radar tag attachment and impact on survival and behavior of three insect pests. | the ability of three cyanoacrylate glues to ensure a durable bond between the colorado potato beetle, leptinotarsa decemlineata (say), the plum curculio, conotrachelus nenuphar (herbst), or the corn rootworms (western corn rootworm, diabrotica virgifera virgifera leconte and northern corn rootworm, diabrotica longicornis smith and lawrence) and the harmonic radar tag without impact on behavior and survival was assessed as part of a study on the use of harmonic radar technology to track these ins ... | 2009 | 19791611 |
| dispersal and mating behavior of diabrotica virgifera virgifera (coleoptera: chrysomelidae) in bt cornfields. | understanding of the mating and dispersal behavior of the western corn rootworm, diabrotica virgifera virgifera (leconte), is essential to predicting potential resistance to bt corn technologies recently deployed to combat this pest. to quantify movement of male beetles, field studies were conducted during 2006 and 2007 in commercial bt cornfields that included the environmental protection agency-mandated 20% refuge acreage. wing traps containing a single virgin female beetle were placed along t ... | 2009 | 19791612 |
| cadherin fragments from anopheles gambiae synergize bacillus thuringiensis cry4ba's toxicity against aedes aegypti larvae. | a peptide from cadherin agcad1 of anopheles gambiae larvae was reported as a synergist of bacillus thuringiensis subsp. israelensis cry4ba's toxicity to the anopheles mosquito (g. hua, r. zhang, m. a. abdullah, and m. j. adang, biochemistry 47:5101-5110, 2008). we report that cr11 to the membrane proximal extracellular domain (mped) (cr11-mped) and a longer peptide, cr9 to cr11 (cr9-11), from agcad1 act as synergists of cry4ba's toxicity to aedes aegypti larvae, but a diabrotica virgifera virgif ... | 2009 | 19801487 |
| 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 ... | 2009 | 19820311 |
| analysis of the predator community of a subterranean herbivorous insect based on polymerase chain reaction. | the identity and impact of trophic linkages within subterranean arthropod communities are challenging to establish, a fact that hinders the development of conservation biological control programs of subterranean herbivores. diabrotica virgifera (the western corn rootworm) is a severe agricultural pest that lives subterraneously during its pre-imaginal stages and succumbs to high levels of pre-imaginal mortality from unknown agents. the guts of 1500 field-collected arthropod predators were analyz ... | 2009 | 20014585 |
| refuge or reservoir? the potential impacts of the biofuel crop miscanthus x giganteus on a major pest of maize. | interest in the cultivation of biomass crops like the c4 grass miscanthus x giganteus (miscanthus) is increasing as global demand for biofuel grows. in the us, miscanthus is promoted as a crop well-suited to the corn belt where it could be cultivated on marginal land interposed with maize and soybean. interactions (direct and indirect) of miscanthus, maize, and the major corn belt pest of maize, the western corn rootworm, (diabrotica virgifera virgifera leconte, wcr) are unknown. adding a perenn ... | 2009 | 20016814 |
| likelihood of multiple mating in diabrotica virgifera virgifera (coleoptera: chrysomelidae). | we evaluated the mating ability of male western corn rootworms, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), for 20 d after initial mating, using a series of laboratory experiments. males mated an average of 2.24 times within 10 d after their first mating and averaged 0.15 matings between days 11 and 20 after their first mating. because estimating the mating frequency in bt/refuge cornfields is critical to developing robust and reliable models predicting bt resistance deve ... | 2009 | 20069837 |
| native resistance to western corn rootworm (coleoptera: chrysomelidae) larval feeding: characterization and mechanisms. | seven maize, zea mays l., genotypes selected for native resistance to western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), larval feeding damage (sum2068, sum2162, crw3(s1)c6, nss1 x crw3(s1)c6, pi583927, crw2(c5), and ar17056-16) were evaluated along with three control maize genotypes in the field for plant damage, larval recovery, adult emergence, root size, and root regrowth. larvae recovered were further analyzed for head capsule width and dry weight and ... | 2009 | 20069867 |
| new syntheses of 1,7-dimethylnonyl propanoate, the western corn rootworm pheromone, in four different ways via cross metathesis, alkylation and coupling reactions. | a mixture of the four stereoisomers of 1,7-dimethylnonyl propanoate, the female sex pheromone of the western corn rootworm (diabrotica virgifera virgifera leconte), was synthesized in four different ways by employing one of the following four reactions as the key step: (i) cross metathesis using the grubbs i catalyst, (ii) cross metathesis using the grubbs ii catalyst, (iii) alkylation of an alkynide anion, and (iv) grignard coupling in the presence of dilithium tetrachlorocuprate. although the ... | 2010 | 20208352 |
| harmonic radar: assessing the impact of tag weight on walking activity of colorado potato beetle, plum curculio, and western corn rootworm. | the impact of electronic dipole tags on the walking activity of three insects was determined using video tracking software. results varied within and between the three species studied. the heaviest tag mounted on the pronotum of the colorado potato beetle, leptinotarsa decemlineata (say), reduced its mean horizontal speed slightly but significantly. the mean horizontal speed of plum curculio, conotrachelus nenuphar (herbst), was significantly reduced by a light tag but not by heavier tags. the m ... | 2010 | 20214369 |
| density-dependent and density-independent mortality of the western corn rootworm: impact on dose calculations of rootworm-resistant bt corn. | the percentage of viable eggs of the western corn rootworm, diabrotica virgifera virgifera leconte, which survived to the adult stage was evaluated for the effect of egg density in 2005 and 2007 in central missouri. in 2005, each plot was 2.44 by 3.05 m and contained 64 maize (corn), zea mays l., plants. in 2007, plots were 3.05 by 3.05 m and again contained 64 corn plants. seven egg densities (2,400, 1,200, 600, 300, 100, 50, and 25 viable eggs per 30.5 cm) were evaluated with four to six repli ... | 2010 | 20214371 |
| evaluating western corn rootworm (coleoptera: chrysomelidae) emergence and root damage in a seed mix refuge. | resistance management is essential for maintaining the efficacy and long-term durability of transgenic corn engineered to control western corn rootworm (diabrotica virgifera virgifera le conte). theoretically, a refuge can be provided by growing susceptible (refuge) plants in either a separate section of the field adjacent to resistant (transgenic) plants, or as a seed mixture. we examined the effects of varying the structure of a 10 and 20% refuge between currently approved structured refuges ( ... | 2010 | 20214380 |
| containment of the western corn rootworm diabrotica v.virgifera: continued successful management 2008 in southern switzerland by monitoring and crop rotation. | diabrotica virgifera virgifera leconte (col.: chrysomelidae), known as western corn rootworm (wcr) and endemic in north america, invaded europe about two decades ago. various unsuccessful attempts have been made to eradicate it from the old world. management with a variety of strategies is the option now remaining. wcr management in southern switzerland by a unique containment approach has been practiced successfully since 2003 using biotechnical means. without any chemical pesticides or gmo inp ... | 2009 | 20222583 |
| lepidopteran-active variable-region sequence imparts coleopteran activity in ecry3.1ab, an engineered bacillus thuringiensis hybrid insecticidal protein. | a unique, coleopteran-active protein, termed ecry3.1ab, was generated following variable-region exchange of a bacillus thuringiensis lepidopteran-active protein, cry1ab, with a cry3a region. our results support the hypothesis that this variable-region exchange is responsible for imparting strong bioactivity against the larvae of western corn rootworm (wcr) (diabrotica virgifera virgifera leconte), a pest species which is not susceptible to either parent protein sequence. this study demonstrates ... | 2010 | 20305020 |
| isolation of transcripts from diabrotica virgifera virgifera leconte responsive to the bacillus thuringiensis toxin cry3bb1. | crystal (cry) proteins derived from bacillus thuringiensis (bt) have been widely used as a method of insect pest management for several decades. in recent years, a transgenic corn expressing the cry3bb1 toxin has been successfully used for protection against corn rootworm larvae (genus diabrotica). the biological action of the bt toxin in corn rootworms has not yet been clearly defined. because development of resistance to bt by corn rootworms will have huge economic and ecological costs, insigh ... | 2010 | 20337747 |
| winter annual cover crop has only minor effects on major corn arthropod pests. | we studied the effects of downy brome, bromus tectorum l., winter cover crop on several corn, zea mays l., pests in the summer crop after the cover crop. an experiment was conducted that consisted of two trials with two levels of irrigation, two levels of weed control, and two levels of downy brome. corn was grown three consecutive years after the downy brome grown during the winter. banks grass mites, oligonychus pratensis (banks), twospotted spider mites, tetranychus urticae koch, and predator ... | 2010 | 20429447 |
| enhancing cry1ac toxicity by expression of the helicoverpa armigera cadherin fragment in bacillus thuringiensis. | insect cadherin proteins localized in the midgut epithelium were identified as receptors for bacillus thuringiensis insecticidal crystal proteins (cry toxins). these cadherins facilitated toxin monomer oligomerization and mediated oligomer binding to secondary receptors. it has been reported that manduca sexta, helicoverpa armigera, anopheles gambiae and diabrotica virgifera cadherin toxin binding regions function as synergists for cry1a, cry4ba and cry3a toxicity against target insects. in the ... | 2010 | 20438837 |
| modeling evolution of diabrotica virgifera virgifera (coleoptera: chrysomelidae) to transgenic corn with two insecticidal traits. | a simulation model of the population dynamics and genetics of western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), was created to evaluate the use of refuges in the management of resistance to transgenic insecticidal corn, zea mays l., expressing one or two toxin traits. hypothetical scenarios and a case study of a corn hybrid pyramided with existing toxins are simulated. in the hypothetical situations, results demonstrated that evolution is generally delaye ... | 2010 | 20568632 |
| microbial symbionts in insects influence down-regulation of defense genes in maize. | diabrotica virgifera virgifera larvae are root-feeding insects and significant pests to maize in north america and europe. little is known regarding how plants respond to insect attack of roots, thus complicating the selection for plant defense targets. diabrotica virgifera virgifera is the most successful species in its genus and is the only diabrotica beetle harboring an almost species-wide wolbachia infection. diabrotica virgifera virgifera are infected with wolbachia and the typical gut flor ... | 2010 | 20596533 |
| evaluation of five methods for total dna extraction from western corn rootworm beetles. | dna extraction is a routine step in many insect molecular studies. a variety of methods have been used to isolate dna molecules from insects, and many commercial kits are available. extraction methods need to be evaluated for their efficiency, cost, and side effects such as dna degradation during extraction. | 2010 | 20730102 |
| the western corn rootworm, a new threat to european agriculture: opportunities for biotechnology? | during the early 1990s, the western corn rootworm, diabrotica virgifera virgifera le conte (wcr), a maize pest, invaded the european continent. the continuous spread of the pest has introduced a new constraint into european maize production. as the damage caused by the invasive species is highly variable and different crop protection (cp) strategies are available, farmers' optimal strategies are not obvious. this study uses a simulation model to assess the competitiveness of different cp strateg ... | 2010 | 20730987 |
| 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 ... | 2011 | 20840610 |
| planting patterns of in-field refuges observed for bt maize in minnesota. | the u.s. environmental protection agency (usepa) requires the use of nontransgenic refuges to slow the evolution of insect resistance to transgenic crops. in-field refuges, or refuges that are planted within the same field as the transgenic crop, are allowed; however, these refuges are required to be at least four rows wide. we described in-field planting patterns used by growers for both crylab [against ostrinia nubilalis (hübner)] and cry3bb (against diabrotica virgifera virgifera leconte) mai ... | 2010 | 20857753 |
| a novel method for estimating soybean herbivory in western corn rootworm (coleoptera: chrysomelidae). | the western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), is the key pest of corn, zea mays l., in north america. the western corn rootworm variant is a strain found in some parts of the united states that oviposits in soybean, glycine max (l.) merr., thereby circumventing crop rotation. soybean herbivory is closely associated with oviposition; therefore, evidence of herbivory could serve as a proxy for rotation resistance. a digital image analysis method bas ... | 2010 | 20857762 |
| relevance of traditional integrated pest management (ipm) strategies for commercial corn producers in a transgenic agroecosystem: a bygone era? | the use of transgenic bt maize hybrids continues to increase significantly across the corn belt of the united states. in 2009, 59% of all maize planted in illinois was characterized as a "stacked" gene variety. this is a 40% increase since 2006. stacked hybrids typically express one cry protein for corn rootworm control and one cry protein for control of several lepidopteran pests; they also feature herbicide tolerance (to either glyphosate or glufosinate). slightly more than 50 years has passed ... | 2010 | 20873716 |
| harmonic radar: efficacy at detecting and recovering insects on agricultural host plants. | in pest management research, harmonic radar systems have been largely used to study insect movement across open or vegetation-poor areas because the microwave signal is attenuated by the high water content of vegetation. this study evaluated whether the efficacy of this technology is sufficient to track insects in vegetative landscapes. | 2011 | 21058275 |
| rna interference as a method for target-site screening in the western corn rootworm, diabrotica virgifera virgifera. | to test the efficacy of rna interference (rnai) as a method for target-site screening in diabrotica virgifera virgifera leconte (coleptera: chrysomelidae) larvae, genes were identified and tested for which clear rnai phenotypes had been identified in the coleopteran model, tribolium castaneum. here the cloning of the d. v. vergifera orthologs of laccase 2 (dvvlac2) and chitin synthase 2 (dvvchs2) is reported. injection of dvvlac2-specific double-stranded rna resulted in prevention of post-molt c ... | 0 | 21067417 |
| influence of soil on the efficacy of entomopathogenic nematodes in reducing diabrotica virgifera virgifera in maize. | the use of entomopathogenic nematodes is one potential non-chemical approach to control the larvae of the invasive western corn rootworm (diabrotica virgifera virgifera leconte, coleoptera: chrysomelidae) in europe. this study investigated the efficacy of heterorhabditis bacteriophora poinar (rhabditida: heterorhabditidae), heterorhabditis megidis poinar, jackson and klein (rh., heterorhabditidae) and steinernema feltiae filipjev (rh., steinernematidae) in reducing d. v. virgifera as a function ... | 2010 | 21124754 |
| antixenosis in maize reduces feeding by western corn rootworm larvae (coleoptera: chrysomelidae). | sum2162 is the first known example of a naturally occurring maize, zea mays l., genotype with antixenosis (nonpreference) resistance to western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), larval feeding. behavioral responses of neonate western corn rootworm larvae were evaluated in laboratory bioassays with seven maize genotypes selected for native resistance to rootworm feeding damage. two susceptible maize genotypes and one transgenic (bacillus thuringien ... | 2010 | 21309225 |
| mortality of western corn rootworm larvae on mir604 transgenic maize roots: field survivorship has no significant impact on survivorship of f1 progeny on mir604. | mortality of western corn rootworm, diabrotica virgifera virgifera leconte, larvae due to mir604 transgenic corn, zea mays l., expressing the modified cry3a (mcry3a) protein relative to survivorship on corn with the same genetic background without the gene (isoline corn) was evaluated at three missouri sites in both 2005 and 2006. we made these comparisons by using wild-type western corn rootworm at three different egg densities (6,000, 3,000, and 1,500 eggs per m) so that the role of density-de ... | 2010 | 21309243 |
| impact of cry3bb1-expressing bt maize on adults of the western corn rootworm, diabrotica virgifera virgifera (coleoptera: chrysomelidae). | genetically engineered maize producing insecticidal cry3bb1 protein from bacillus thuringiensis (bt) is protected from root damage by corn rootworm larvae. an examination was made to establish whether western corn rootworm (diabrotica virgifera virgifera) adults are affected by cry3bb1-expressing maize (mon88017) when feeding on above-ground tissue. | 2011 | 21360646 |
| belowground resistance to western corn rootworm in lepidopteran-resistant maize genotypes. | several maize, zea mays l., inbred lines developed from an antiguan maize population have been shown to exhibit resistance to numerous aboveground lepidopteran pests. this study shows that these genotypes are able to significantly reduce the survival of two root feeding pests, western corn rootworm, diabrotica virgifera virgifera leconte, and southern corn rootworm, diabrotica undecimpunctata howardi barber. the results also demonstrated that feeding by the aboveground herbivore fall armyworm, s ... | 2011 | 21404871 |
| systemic root signalling in a belowground, volatile-mediated tritrophic interaction. | plants attacked by leaf herbivores release volatile organic compounds (vocs) both locally from the wounded site and systemically from non-attacked tissues. these volatiles serve as attractants for predators and parasitoids. this phenomenon is well described for plant leaves, but systemic induction of vocs in the roots has remained unstudied. we assessed the spatial and temporal activation of the synthesis and release of (e)-β-caryophyllene (eβc) in maize roots upon feeding by larvae of diabrotic ... | 2011 | 21477121 |
| assessing the risk posed to free-living soil nematodes by a genetically modified maize expressing the insecticidal cry3bb1 protein. | before pest-resistant genetically modified maize can be grown commercially, the risks for soil-beneficial, non-target organisms must be determined. here, a tiered approach was used to assess the risk to free-living soil nematodes posed by maize genetically modified to express the insecticidal cry3bb1 protein (event mon88017), which confers resistance towards western corn rootworm (diabrotica virgifera; coleoptera). the toxicity of purified cry3bb1 for the nematode caenorhabditis elegans was dete ... | 2011 | 21511326 |
| the influence of weather and geographical conditions on flight dynamics of wcr adults. | since the appearance of western corn rootworm (diabrotica virgifera virgifera le conte) (coleoptera: chrysometidae) in romania, many researchers have been made, in more or less success. in this study we try to clarify the ecology of the species in order to predict its evolution and its potential area of distribution. in romania, this species was signalled for the first time in 1996, in western part of country neighbouring with hungary. this region is an important area for maize production for se ... | 2010 | 21539248 |
| attraction of heterorhabditis sp. toward synthetic (e)-beta-cariophyllene, a plant sos signal emitted by maize on feeding by larvae of diabrotica virgifera virgifera. | most plants, when damaged by herbivore insects, synthesize and release various chemicals as indirect defence mechanism that attract parasitic or predatory insects that are natural enemies of the herbivores. when attacked by western corn rootworms, the roots of many maize plant varieties emit (e)-beta-caryophyllene that attracts the neighbouring entomopathogenic nematodes to kill the feeding pest. through plant genetics and biotechnology it was possible to manipulate this volatile compound in ord ... | 2010 | 21539265 |
| weed control in conventional and transgenic maize with resistance to glyphosate. | the researches were conducted in order to observe the behaviour of conventional and glyphosate resistant transgenic maize to different weed control methods. in this paper, the obtained results are presented. the study was conducted in experimental years 2008-2009 in the frame of didactical station usamvb timisoara. in order to conduct this study, 4 variants cultivated with conventional maize dkc 5143 and 8 variants cultivated with transgenic maize dkc-mon88017 with resistance against diabrotica ... | 2010 | 21542472 |
| polymorphic microsatellite loci from northern and mexican corn rootworms (insecta: coleoptera: chrysomelidae) and cross-amplification with other diabrotica spp. | the northern corn rootworm (diabrotica barberi) and mexican corn rootworm (diabrotica virgifera zeae) are significant agricultural pests. for the northern corn rootworm, and to a lesser extent, the mexican corn rootworm, high resolution molecular markers are needed. here we present 14 polymorphic microsatellite loci isolated from libraries constructed using pooled northern and mexican corn rootworm genomic dna. polymorphism in other diabrotica, including the banded cucumber beetle, southern corn ... | 2008 | 21585878 |
| generalist-feeding subterranean mites as potential biological control agents of immature corn rootworms. | predatory mites are important components of subterranean food webs and may help regulate densities of agricultural pests, including western corn rootworms (chrysomelidae: diabrotica virgifera virgifera). implementing conservation and/or classical biocontrol tactics could enhance densities of specialist or generalist predatory mites and lead to pest suppression, but first relevant mite species must be identified and their predatory capabilities evaluated. we conducted lab assays to quantify consu ... | 2011 | 21598089 |
| effects of the training dataset characteristics on the performance of nine species distribution models: application to diabrotica virgifera virgifera. | many distribution models developed to predict the presence/absence of invasive alien species need to be fitted to a training dataset before practical use. the training dataset is characterized by the number of recorded presences/absences and by their geographical locations. the aim of this paper is to study the effect of the training dataset characteristics on model performance and to compare the relative importance of three factors influencing model predictive capability; size of training datas ... | 2011 | 21701579 |
| bt maize and integrated pest management-a european perspective. | the european corn borer (ostrinia nubilalis), the mediterranean corn borer (sesamia nonagrioides) and the western corn rootworm (diabrotica virgifera virgifera) are the main arthropod pests in european maize production. practised pest control includes chemical control, biological control and cultural control such as ploughing and crop rotation. a pest control option that is available since 1996 is maize varieties that are genetically engineered (ge) to produce insecticidal compounds. ge maize va ... | 2011 | 21710684 |
| selection for cry3bb1 resistance in a genetically diverse population of nondiapausing western corn rootworm (coleoptera: chrysomelidae). | five short-diapause laboratory lines of western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), were selected for resistance to mon863, a variety of corn genetically modified with the bacillus thuringiensis berliner (bt) transgene that expresses the cry3bb1 delta-endotoxin. three of the selected lines were developed by incremental increase in the duration of exposure to mon863 over 11 generations (moderate selected lines). two selected lines were developed from ... | 2011 | 21735927 |
| selection for resistance to mcry3a-expressing transgenic corn in western corn rootworm. | to investigate the development of resistance to mcry3a, a laboratory colony of the western corn rootworm, diabrotica virgifera virgifera leconte, was established from field survivors of mcry3a-expressing (mir604) corn, zea mays l. feral adults emerging from mir604 (selected) and isoline (control) field plots were collected and returned to the laboratory. progeny of each colony was reared one generation on isoline corn and then crossed reciprocally with a nondiapausing colony. the resulting nondi ... | 2011 | 21735928 |
| field-evolved resistance to bt maize by western corn rootworm. | crops engineered to produce insecticidal toxins derived from the bacterium bacillus thuringiensis (bt) are planted on millions of hectares annually, reducing the use of conventional insecticides and suppressing pests. however, the evolution of resistance could cut short these benefits. a primary pest targeted by bt maize in the united states is the western corn rootworm diabrotica virgifera virgifera (coleoptera: chrysomelidae). | 2011 | 21829470 |
| a multi-scale, landscape approach to predicting insect populations in agroecosystems. | landscape composition affects ecosystems services, including agricultural pest management. however, relationships between land use and agricultural insects are not well understood, and many complexities remain to be explored. here we examine whether nonagricultural landscapes can directly suppress agricultural pests, how multiple spatial scales of land use concurrently affect insect populations, and the relationships between regional land use and insect populations. we tracked densities of three ... | 2011 | 21830718 |
| mortality impact of bt transgenic maize roots expressing ecry3.1ab, mcry3a, and ecry3.1ab plus mcry3a on western corn rootworm larvae in the field. | mortality of the western corn rootworm, diabrotica virgifera virgifera leconte, larvae due to feeding on maize, zea mays l., expressing bacillus thuringiensis berliner (bt) was evaluated in five missouri sites in 2007, 2008, and 2009. specifically, ecry3.1ab (5307), mcry3a (mir604), and ecry3.1ab plus mcry3a proteins relative to survivorship on maize with the same genetic background without these genes (isoline maize) was evaluated. an average of 890.8 +/- 152.3 beetles emerged from isoline plot ... | 2011 | 22066188 |
| a specialist root herbivore exploits defensive metabolites to locate nutritious tissues. | the most valuable organs of plants are often particularly rich in essential elements, but also very well defended. this creates a dilemma for herbivores that need to maximise energy intake while minimising intoxication. we investigated how the specialist root herbivore diabrotica virgifera solves this conundrum when feeding on wild and cultivated maize plants. we found that crown roots of maize seedlings were vital for plant development and, in accordance, were rich in nutritious primary metabol ... | 2012 | 22070646 |
| the effects of a winter cover crop on diabrotica virgifera (coleoptera: chrysomelidae) populations and beneficial arthropod communities in no-till maize. | the effects of an autumn-planted, spring-killed, grass cover crop (elymus trachycaulus [link] gould ex shinners) on populations of diabrotica virgifera virgifera leconte and its predator community were evaluated in south dakota maize fields over two seasons. abundance and size of d. virgifera larvae and adults and sex ratio of adults were measured in maize produced under two treatments (i.e., a winter cover crop or bare soil), as were maize root damage and the abundance and diversity of the pred ... | 2010 | 22182547 |
| oviposition behaviors in relation to rotation resistance in the western corn rootworm. | across a large area of the midwestern united states corn belt, the western corn rootworm beetle (diabrotica virgifera virgifera leconte, coleoptera: chrysomelidae) exhibits behavioral resistance to annual crop rotation. resistant females exhibit increased locomotor activity and frequently lay eggs in soybean (glycine max l.) fields, although they also lay eggs in fields of corn (zea mays l.) and other locations. the goals of this study were (1) to determine whether there were any differences in ... | 2010 | 22182558 |
| Evaluation of tag entanglement as a factor in harmonic radar studies of insect dispersal. | The observation of insects and other small organisms entangled in the habitat after the addition of vertical or trailing electronic tags to their body has generated concerns on the suitability of harmonic radars to track the dispersal of insects. This study compared the walking behavior of adult Colorado potato beetle (Leptinotarsa decemlineata (Say) Chrysomelidae), plum curculio (Conotrachelus nenuphar (Herbst) Curculionidae), and western corn rootworm (Diabrotica virgifera virgifera (LeConte) ... | 2011 | 22182617 |
| mating success and spermatophore composition in western corn rootworm (coleoptera: chrysomelidae). | western corn rootworm (diabrotica virgifera virgifera leconte) resistance management for transgenic (or bt) corn hinges on understanding the mating behavior and biology of this adaptable insect pest. during mating, the male transfers sperm and additional, previously uncharacterized material, to the female in the form of a spermatophore. we investigated the composition of rootworm spermatophores. proteins were found to be a major component, and the stable isotope (15)n was used to assess the fate ... | 2011 | 22217777 |
| western corn rootworm (coleoptera: chrysomelidae) dispersal and adaptation to single-toxin transgenic corn deployed with block or blended refuge. | a simulation model of the temporal and spatial dynamics and population genetics of western corn rootworm, diabrotica virgifera virgifera leconte, was created to evaluate the use of block refuges and seed blends in the management of resistance to transgenic insecticidal corn (zea mays l.). this bt corn expresses one transgenic corn event, das-59122-7, that produces a binary insecticidal protein toxin (cry34ab1/cry35ab1) and provides host-plant resistance. the model incorporates the latest informa ... | 2011 | 22251698 |
| effect of mir604 transgenic maize at different stages of development on western corn rootworm (coleoptera: chrysomelidae) in a central missouri field environment. | the establishment and survival of western corn rootworm, diabrotica virgifera virgifera leconte, was evaluated on transgenic bacillus thuringiensis berliner maize, zea mays l., expressing the mcry3a protein (mir604) and non-bt maize with the same genetic background (isoline maize) at different stages of development in 2007 and 2008. overall, western corn rootworm larval recovery, root damage, and adult emergence were significantly higher on isoline maize compared with mir604. the number of larva ... | 2011 | 22299370 |
| herbivore-induced plant volatiles mediate host selection by a root herbivore. | in response to herbivore attack, plants mobilize chemical defenses and release distinct bouquets of volatiles. aboveground herbivores are known to use changes in leaf volatile patterns to make foraging decisions, but it remains unclear whether belowground herbivores also use volatiles to select suitable host plants. we therefore investigated how above- and belowground infestation affects the performance of the root feeder diabrotica virgifera virgifera, and whether the larvae of this specialized ... | 2012 | 22486361 |
| validation of rna interference in western corn rootworm diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae) adults. | rna interference (rnai) is commonly used in insect functional genomics studies and usually involves direct injection of double-stranded rna (dsrna). only a few studies have involved exposure to dsrnas through feeding. for western corn rootworm (diabrotica virgifera virgifera) larvae, ingestion of dsrna designed from the housekeeping gene, vacuolar atpase (vatpase) triggers rnai causing growth inhibition and mortality; however, the effect of dsrna feeding on adults has not been examined. in this ... | 2012 | 22500293 |
| induced immunity against belowground insect herbivores- activation of defenses in the absence of a jasmonate burst. | roots respond dynamically to belowground herbivore attack. yet, little is known about the mechanisms and ecological consequences of these responses. do roots behave the same way as leaves, or do the paradigms derived from aboveground research need to be rewritten? this is the central question that we tackle in this article. to this end, we review the current literature on induced root defenses and present a number of experiments on the interaction between the root herbivore diabrotica virgifera ... | 2012 | 22527052 |