Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| negative phototactic activity used to determine larval toxicity of insecticides to diabrotica virgifera. | 1975 | 1141486 | |
| insecticidal activity of monoterpenoids to western corn rootworm (coleoptera: chrysomelidae), twospotted spider mite (acari: tetranychidae), and house fly (diptera: muscidae). | acute toxicities of 34 naturally occurring monoterpenoids were evaluated against 3 important arthropod pest species; the larva of the western corn rootworm, diabrotica virgifera virgifera leconte; the adult of the twospotted spider mite. tetranychus urticae koch; and the adult house fly. musca domestica l. potential larvicidal or acaricidal activities of each monoterpenoid were determined by topical application, leaf-dip method, soil bioassay, and greenhouse pot tests. phytotoxicity was also tes ... | 1997 | 9260540 |
| the role of wolbachia bacteria in reproductive incompatibilities and hybrid zones of diabrotica beetles and gryllus crickets. | a rickettsial bacterium in the genus wolbachia is the cause of a unidirectional reproductive incompatibility observed between two major beetle pests of maize, the western corn rootworm, diabrotica virgifera virgifera, and the mexican corn rootworm, d. v. zeae. these subspecies are allopatric except for two known regions of sympatry in texas and mexico. we demonstrate that populations of d. v. virgifera, with the exception of two populations in southern arizona, are infected with a strain of wolb ... | 1997 | 9326628 |
| interaction of insecticides, entomopathogenic nematodes, and larvae of the western corn rootworm (coleoptera: chrysomelidae). | chemical insecticides and entomopathogenic nematodes have been independently used to suppress corn rootworm damage in maize. we report on the mortality response of larvae of the western corn rootworm, diabrotica virgifera virgifera leconte, to the combined treatment with 1 of 3 insecticides (terbufos, fonofos, and tefluthrin) and the entomopathogenic nematode steinernema carpocapsae weiser (mexican strain). corn rootworm mortality with combinations of the insecticides terbufos or fonofos and s. ... | 1998 | 9589627 |
| purification and kinetic analysis of acetylcholinesterase from western corn rootworm, diabrotica virgifera virgifera (coleoptera: chrysomelidae). | acetylcholinesterase (ache, ec 3.1.1.7) was purified from western corn rootworm (wcr, diabrotica virgifera virgifera) beetles by affinity chromatography. the purification factor reached over 20,000-fold with a specific activity of 169.5 mumol/min/mg and a yield of 23%. the vmax values for hydrolyzing acetylthiocholine (atc), acetyl-(beta-methyl) thiocholine (a beta mtc), propionylthiocholine (ptc), and s-butyrylthiocholine (btc) were 184.8, 140.5, 150.2, and 18.8 mumol/min/mg, respectively, and ... | 1998 | 9880902 |
| lipid, polyamide, and flavonol phagostimulants for adult western corn rootworm from sunflower (helianthus annuus l.) pollen. | adult diabroticites including western corn rootworm (wcr), diabrotica virgifera virgifera leconte, consume pollen of corn, squash, sunflower, and other species. short-chain neutral amino acids in methanol-water extracts of pollen have been previously identified in our laboratory as strong phagostimulants for diabrotica. bioassay-driven fractionation was used to characterize the interacting lipid and midpolarity phagostimulants for adult wcr in giant gray stripe sunflower, helianthus annuus l., p ... | 1999 | 10552441 |
| genetic variation in geographical populations of western and mexican corn rootworm. | genetic variation in the nuclear rdna its1 region of western corn rootworm, diabrotica virgifera virgifera (wcr), and mexican corn rootworm, d. v. zeae (mcr) was studied. two sites were detected which differentiated wcr and mcr in the 642-base sequence. polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) analysis of the first internal transcribed spacer region (its1) sequence revealed no variation within or among the twelve wcr and two mcr populations. pcr-rflp of 75% o ... | 1999 | 10620046 |
| allozyme gene diversities in some leaf beetles (coleoptera: chrysomelidae). | gene diversity at allozyme loci was investigated in the bean leaf beetle, ceratoma trifurcata forster; the elm leaf beetle, xanthogaleruca luteola (muller); the cottonwood leaf beetle, chrysomela scripta fabricus; the western corn rootworm, diabrotica virgifera virgifera leconte; the southern corn rootworm, also called the spotted cucumber beetle, d. undecimpunctata howardi baker; the northern corn rootworm, d. barberi smith and lawrence; and the colorado potato beetle, leptinotarsa decemlineata ... | 1999 | 10624512 |
| a plant defensive cystatin (soyacystatin) targets cathepsin l-like digestive cysteine proteinases (dvcals) in the larval midgut of western corn rootworm (diabrotica virgifera virgifera). | feeding bioassay results established that the soybean cysteine proteinase inhibitor n (soyacystatin n, scn) substantially inhibits growth and development of western corn rootworm (wcr), by attenuating digestive proteolysis [zhao, y. et al. (1996) plant physiol. 111, 1299-1306]. recombinant scn was more inhibitory than the potent and broad specificity cysteine proteinase inhibitor e-64. wcr digestive proteolytic activity was separated by mildly denaturing sds-page into two fractions and in-gel as ... | 2000 | 10760514 |
| an in-gel assay of a recombinant western corn rootworm (diabrotica virgifera virgifera) cysteine proteinase expressed in yeast. | 2000 | 10860514 | |
| cdna cloning, biochemical characterization and inhibition by plant inhibitors of the alpha-amylases of the western corn rootworm, diabrotica virgifera virgifera. | we report the characterization and cdna cloning of two alpha-amylase isozymes from larvae of the western corn rootworm (diabrotica virgifera virgifera leconte). larvae raised on artificial media have very low levels of amylase activity, and much higher levels are found in larvae raised on maize seedlings. at ph 5.7, the optimum ph for enzyme activity, the alpha-amylases are substantially but not completely inhibited by amylase inhibitors from the common bean (phaseolus vulgaris) and from wheat ( ... | 2000 | 10899464 |
| foraging resources of adult mexican corn rootworm (coleoptera: chrysomelidae) in bell county, texas. | pollen analyses were used to determine pollen foraging resources of adult mexican corn rootworms, diabrotica virgifera zeae krysan & smith, captured near temple, bell county, tx, in 1996 and 1997. in 1996, adult mexican corn rootworms were captured in a corn, zea mays l., field. in 1997, nine locations outside of cornfields were added. overall, 92% of the beetles (n = 1,323) contained pollen. more than 142,000 pollen grains were counted, representing 45 families, 63 genera, and 27 species. overa ... | 2000 | 10902309 |
| impact of western corn rootworm (coleoptera: chrysomelidae) on sweet corn and evaluation of insecticidal and cultural control options. | the western corn rootworm, diabrotica virgifera virgifera leconte, is an important pest of corn, zea mays l., causing yield losses from root damage, plant lodging, and silk feeding. because little is known about its impact on sweet corn, we conducted research to evaluate the combined effects of insecticide, planting date, and cultivar on root damage, plant lodging, and yield in central new york sweet corn. we also examined the influence of planting date and cultivar on the emergence of adult wes ... | 2000 | 10902334 |
| identification and quantification of hydroxamic acids in maize seedling root tissue and impact on western corn rootworm (coleoptera: chrysomelidae) larval development. | hydroxamic acid content was analyzed in the root tissue of four maize, zea mays l., lines using high-performance liquid chromatography (hplc) and related to western corn rootworm, diabrotica virgifera virgifera leconte, larval development and survivorship. maize lines evaluated included mp710 (pi 596627), mpswcb-4, (pi 550498), sc213 (pi 548792), and dk580 (dekalb commercial hybrid). maize plants from each line were grown in test tubes containing a transparent agarose gel medium in a growth cham ... | 2000 | 10902360 |
| evaluation of conventional resistance to european corn borer (lepidoptera: crambidae) and western corn rootworm (coleoptera: chrysomelidae) in experimental maize lines developed from a backcross breeding program. | plant resistance is a promising control method for the two most damaging insect pests of maize, zea mays l.: the european corn borer, ostrinia nubilalis (hübner), and the western corn rootworm diabrotica virgifera virgifera leconte. fifteen experimental lines of maize, derived from a backcross breeding program designed to introgress resistance to european corn borer from peruvian maize into two u.s. corn belt adapted inbred lines, were evaluated for resistance to european corn borer and western ... | 2000 | 11142317 |
| influence of western corn rootworm (coleoptera: chrysomelidae) larval injury on yield of different types of maize. | two field experiments were conducted in 1995-1996 to determine if there are common yield responses among maize hybrids to larval western corn rootworm, diabrotica virgifera virgifera leconte injury. three yellow dent hybrids, five white food grade dent hybrids, and a popcorn hybrid were included in the study. the minimum level of rootworm injury as measured by root damage ratings (3.2-4.2) that significantly reduced yield was similar across the hybrids included in the study. however, the pattern ... | 2001 | 11233098 |
| predicting western corn rootworm (coleoptera: chrysomelidae) larval injury to rotated corn with pherocon am traps in soybeans. | crop rotation for portions of east central illinois and northern indiana no longer adequately protects corn (zea mays l.) roots from western corn rootworm, diabrotica virgifera virgifera leconte. seventeen growers in east central illinois monitored western corn rootworm adults in soybean (glycine max l.) fields with unbaited pherocon am traps during 1996 and 1997. in the following years (1997 and 1998), growers left untreated strips (no insecticide applied) when these fields were planted with co ... | 2001 | 11233140 |
| modeling the dynamics of adaptation to transgenic corn by western corn rootworm (coleoptera: chrysomelidae). | a simulation model of the population dynamics and genetics of the western corn rootworm, diabrotica virgifera virgifera leconte, was created for a landscape of corn, soybean, and other crops. although the model was created to study a 2-locus problem for beetles having genes for resistance to both crop rotation and transgenic corn, during this first phase of the project, the model was simulated to evaluate only resistance management plans for transgenic corn. allele expression in the rootworm and ... | 2001 | 11332850 |
| linkages between fao agroclimatic data resources and the development of gis models for control of vector-borne diseases. | the food and agriculture organization (fao) of the united nations is the largest specialized un agency dealing with agriculture, forestry and fishery, particularly in the developing countries. one of its technical services, placed under the sustainable development department, has the responsibility to provide information on environment and natural resources as related to food and agriculture. it includes, among others, expertise in remote sensing, geographic information systems and agrometeorolo ... | 2001 | 11378139 |
| expression and induction of three family 4 cytochrome p450 (cyp4)* genes identified from insecticide-resistant and susceptible western corn rootworms, diabrotica virgifera virgifera. | we have previously determined that cytochrome p450-based oxidation is involved in resistance to the insecticides methyl parathion and carbaryl in geographically distinct nebraska western corn rootworm populations. three new family 4 cytochrome p450 (cyp4) gene fragments (cyp4aj1, cyp4g18 and cyp4ak1) were cloned and sequenced from insecticide-resistant and -susceptible western corn rootworms. insecticide bioassays indicated the resistant population employed in this study was significantly resist ... | 2001 | 11422509 |
| insecticidal proteins from bacillus thuringiensis protect corn from corn rootworms. | field tests of corn co-expressing two new delta-endotoxins from bacillus thuringiensis (bt) have demonstrated protection from root damage by western corn rootworm (diabrotica virgifera virgifera leconte). the level of protection exceeds that provided by chemical insecticides. in the bacterium, these proteins form crystals during the sporulation phase of the growth cycle, are encoded by a single operon, and have molecular masses of 14 kda and 44 kda. corn rootworm larvae fed on corn roots express ... | 2001 | 11433280 |
| single and blended maize volatiles as attractants for diabroticite corn rootworm beetles. | synthetic maize volatiles and analogs dispensed singly and blended were tested for attractiveness to western (wcr, diabrotica virgifera virgifera) and northern corn rootworm beetles (ncr, d. barberi) in maize fields. newly identified attractants included syn-benzaldoxime, especially for ncr, and beta-caryophyllene for wcr females. (+/-)-linalool was more effective than was (-)-linalool. myrcene, (+)-beta-pinene, and (-)-beta-pinene were unattractive. adding methyl salicylate to (+/-)-linalool, ( ... | 2001 | 11504034 |
| evidence of evolving carbaryl resistance in western corn rootworm (coleoptera: chrysomelidae) in areawide-managed cornfields in north central kansas. | susceptibility of adult populations of the western corn rootworm, diabrotica virgifera virgifera leconte, to carbaryl was determined by a survey in 1996 before the implementation of an areawide management program near scandia in north central kansas. subsequently, the susceptibility of western corn rootworm adults to carbaryl has been monitored throughout the program from 1997 to 2000 in both control and managed areas. in 1996, adults were highly susceptible to carbaryl with a mean lc50 value of ... | 2001 | 11561854 |
| evolution of diabroticite rootworm beetle (chrysomelidae) receptors for cucurbita blossom volatiles. | the diabroticite rootworm beetles coevolved with plants of the family cucurbitaceae as demonstrated by their feeding dependence on the tetracyclic triterpenoid cucurbitacins. these beetles also exhibit strong attraction to phenylpropanoid volatile components of cucurbita blossoms. a mixture of 1,2,4-trimethoxybenzene, indole, and (e)-cinnamaldehyde, all blossom components, is highly attractive to the several species of diabroticite cucumber beetles and corn rootworms and is considered a simplifi ... | 1991 | 11607158 |
| consumption of residue containing cucurbitacin feeding stimulant and reduced rates of carbaryl insecticide by western corn rootworm (coleoptera: chrysomelidae). | application of insecticide at a reduced rate with a cucurbitacin-based feeding stimulant is a viable alternative to a broadcast insecticide application for control of adult western corn rootworms, diabrotica virgifera virgifera, leconte. because of the small amount of material applied, it is conceivable that a high density of beetles could consume all of the spray residue before economic control is achieved. a laboratory experiment was conducted to determine the amount of cucurbitacin-based spra ... | 2001 | 11777045 |
| field resistance of two soybean germplasm lines, hc95-15mb and hc95-24mb, against bean leaf beetle (coleoptera: chrysomelidae), western corn rootworm (coleoptera: chrysomelidae), and japanese beetles (coleoptera: scarabaidae). | two recently released, mexican bean beetle, epilachna varivestis, mulsant, resistant soybean, glycine max (l.) merrill, germplasm lines, hc95-15mb and hc95-24mb, were examined for foliar and pod feeding resistance to adult bean leaf beetles, cerotoma trifurcata (forster), western corn rootworms, diabrotica virgifera virgifera leconte, and japanese beetles, popillia japonica newman. both lines were planted along with a susceptible control cultivar in 18 by 30-m plots and separate 0.8-ha size fiel ... | 2001 | 11777070 |
| novel bacillus thuringiensis binary insecticidal crystal proteins active on western corn rootworm, diabrotica virgifera virgifera leconte. | a new family of insecticidal crystal proteins was discovered by screening sporulated bacillus thuringiensis cultures for oral activity against western corn rootworm (wcr) larvae. b. thuringiensis isolates ps80jj1, ps149b1, and ps167h2 have wcr insecticidal activity attributable to parasporal inclusion bodies containing proteins with molecular masses of ca. 14 and 44 kda. the genes encoding these polypeptides reside in apparent operons, and the 14-kda protein open reading frame (orf) precedes the ... | 2002 | 11872461 |
| effects of a potato cysteine proteinase inhibitor on midgut proteolytic enzyme activity and growth of the southern corn rootworm, diabrotica undecimpunctata howardi (coleoptera: chrysomelidae). | the major proteinase activity in extracts of larval midguts from the southern corn rootworm (scr), diabrotica undecimpunctata howardi, was identified as a cysteine proteinase that prefers substrates containing an arginine residue in the p1 position. gelatin-zymogram analysis of the midgut proteinases indicated that the artificial diet-fed scr, corn root-fed scr, and root-fed western corn rootworms (diabrotica virgifera virgifera) possess a single major proteinase with an apparent molecular mass ... | 2002 | 11886775 |
| comparison of adult corn rootworm (coleoptera: chrysomelidae) sampling methods. | studies were conducted in kansas corn and soybean fields during 1997 to compare various sampling methods, traps, and trap components for capturing three species of adult corn rootworms: western (diabrotica virgifera virgifera leconte), southern (d. undecimpunctata howardi barber), and northern (d. barberi smith & lawrence). lure constituents affected the species of beetle attracted to the trap. traps with a lure containing 4-methoxycinnamaldehyde attracted more western corn rootworms, those with ... | 2002 | 11942770 |
| effects of row spacing and plant density on corn rootworm (coleoptera: chrysomelidae) emergence and damage potential to corn. | planting corn, zea mays l., in row spacings less than the conventional width of 76 cm has been shown to increase grain yields. this study was conducted to determine if row spacing and plant density affected corn rootworm, diabrotica virgifera virgifera leconte and d. barberi smith & lawrence, adult emergence, larval injury to the roots, and plant tolerance to injury. field experiments were conducted at ames and nashua, ia, in 1998, 1999, and 2000. treatments were row spacings of 38 and 76 cm, an ... | 2002 | 12076002 |
| binary insecticidal crystal protein from bacillus thuringiensis, strain ps149b1: effects of individual protein components and mixtures in laboratory bioassays. | a family of novel binary insecticidal crystal proteins, with activity against western corn rootworm, diabrotica virgifera virgifera leconte, was identified from bacillus thuringiensis berliner. a binary insecticidal crystal protein (bicp) from b. thuringiensis strain ps149b1 is composed of a 14-kda protein (cry34abl) and a 44-kdaprotein (cry35ab1). these proteins have been co-expressed in transgenic maize plants, zea mays l., and effectively control western corn rootworm larvae under field condi ... | 2002 | 12076012 |
| distribution patterns of mca-coated corn grit formulation after aerial application to maize fields. | field studies in corn (zea mays l.) were conducted during the summer of 2000 to evaluate distribution patterns of corn grits treated with mca (4-methoxy cinnamaldehyde). aerial application was used in a 8 ha corn field situated in south-east hungary. corn granules ('grits') of 10-12 mesh size were applied on july 18th, august 1st and august 28th at rates of 18.3, 21.9 and 20.2 kg grits/ha and were covered with 80, 119 and 120 g mca/ha. experiments were evaluated by collecting grits in 30-cm plas ... | 2001 | 12425055 |
| diagnostic assays based on esterase-mediated resistance mechanisms in western corn rootworms (coleoptera: chrysomelidae). | resistance to methyl-parathion among nebraska western corn rootworm, diabrotica virgifera virgifera leconte, populations is associated with increased hydrolytic metabolism of an organophosphate insecticide substrate. an electrophoretic method to identify resistant individuals based on the staining intensity of esterase isozymes on nondenaturing polyacrylamide gels was developed. three groups of esterases (i, ii, and iii) were visible on the gels, but only group ii esterase isozymes were intensif ... | 2002 | 12539840 |
| impact of cysteine proteinase inhibition in midgut fluid and oral secretion on fecundity and pollen consumption of western corn rootworm (diabrotica virgifera virgifera). | cysteine proteinases predominate in the midgut fluid (mf) and oral secretion (os) of adult western corn rootworm (wcr) based on their mild acidic ph optima (ph 6.0), enhanced activities after treatment with thiol reducing agents, and inhibition by selective cysteine proteinase inhibitors (pis). four cysteine pis including e-64, calpeptin, calpain inhibitor ii, and leupeptin (also a serine pi) strongly inhibited azocaseinolytic activity in a dose-dependent manner in both the mf and os. the most s ... | 2003 | 12587142 |
| inheritance of methyl-parathion resistance in nebraska western corn rootworm populations (coleoptera: chrysomelidae). | field populations of western corn rootworm, diabrotica virgifera virgifera leconte, were collected from three different sites (york co., phelps co., and saunders co.) in nebraska during 1996. adult bioassays of these three populations were conducted with different concentrations of methyl-parathion and at a diagnostic concentration (1.0 microg/ml) to determine resistance levels among these populations. self and reciprocal crosses were made between the two resistant and one susceptible laboratory ... | 2003 | 12650355 |
| distribution of mca-coated grits in maize fields after high wheel tractor application for disrupting orientation of diabrotica virgifera virgifera leconte. | high wheel tractor applications of 4-methoxycinnamaldehyde (mca)-coated corn granules ('grits') were conducted in ruski krstur (serbia) in summer 2001 in a 5 ha corn field. grits are a by-product after corn is harvested and separated from the cob and used as a carrier medium to disseminate mca into the corn field. mca is a kairomone mimic derived form cucurbita maxima (duchesne) used to disrupt orientation of diabrotica virgifera virgifera leconte towards different mca and pheromone baited traps ... | 2002 | 12696417 |
| behavioral and electrophysiological dose-response relationships in adult western corn rootworm (diabrotica virgifera virgifera leconte) for host pollen amino acids. | a strong correlation is shown between taste cell inputs and phagostimulatory outputs with predominant dietary pollen amino acids for western corn rootworm, diabrotica virgifera virgifera. behavioral and electrophysiological dose-response profiles in adult beetles are presented for five major free amino acids in host pollens. differential responses were found with strongest phagostimulation and sensory response elicited by l-alanine and l-serine, followed in order by l-proline and beta-alanine. g ... | 1998 | 12770166 |
| antifeedant effects of proteinase inhibitors on feeding behaviors of adult western corn rootworm (diabrotica virgifera virgifera). | low-molecular-weight peptidyl proteinase inhibitors (pis) including leupeptin, calpain inhibitor i, and calpeptin were found to be potent antifeedants for adult western corn rootworm (wcr) against the phagostimulation of cucurbitacin b (cuc b) or a corn pollen extract (cpe). leupeptin was the strongest (ed50 = 0.36 and 0.55 nmol/disk for cuc b and cpe, respectively) among pis tested with an antifeedant potency much stronger than the steroid progesterone (ed50 = 2.29 and 5.05 nmol/disk for cuc b ... | 2003 | 12775144 |
| post-establishment movement of western corn rootworm larvae (coleoptera: chrysomelidae) in central missouri corn. | if registered, transgenic corn, zea mays l., with corn rootworm resistance will offer a viable alternative to insecticides for managing diabrotica spp. corn rootworms. resistance management to maintain susceptibility is in the interest of growers, the environmental protection agency, and industry, but little is known about many aspects of corn rootworm biology required for an effective resistance management program. the extent of larval movement by the western corn rootworm, diabrotica virgifera ... | 2003 | 12852594 |
| multiplex polymerase chain reaction method for differentiating western and northern corn rootworm larvae (coleoptera: chrysomelidae). | western corn rootworm, diabrotica virgifera virgifera leconte, and northern corn rootworm, d. barberi smith and lawrence, are sympatric species and serious pests of corn cultivation in north america. comparison of nucleotide sequence of mitochondrial cytochrome oxidase i and ii was used to design polymerase chain reaction (pcr) primers that discriminate immature stages of the two species based on differences in amplicon size. multiplex pcr can be used to give a positive test for each species in ... | 2003 | 12852603 |
| captures of western corn rootworm (coleoptera: chrysomelidae) adults with pherocon am and vial traps in four crops in east central illinois. | it is hypothesized that the long-term rotation of maize (zea mays l.) and soybean (glycine max l.) in east central illinois has caused a significant change in the ovipositional behavior of the western corn rootworm, diabrotica virgifera virgifera leconte. since the mid 1990s in east central illinois, western corn rootworm adults have been observed feeding on soybean foliage and also now use soybean fields as egg laying sites. this behavioral adaptation has greatly decreased the effectiveness of ... | 2003 | 12852611 |
| rapid digestion of cry34ab1 and cry35ab1 in simulated gastric fluid. | two genes were identified in bacillus thuringiensis berliner (bt) that code for the proteins that comprise a cry34ab1/cry35ab1 binary insecticidal crystal protein. maize, zea mays l., plants have been transformed to express the cry34ab1/cry35ab1 proteins, and as a result, these plants are resistant to attack by western corn rootworm, diabrotica virgifera virgifera leconte, a major pest in the midwestern corn-growing area of the u.s.a. as part of the safety assessment for the proteins, digestibil ... | 2003 | 14582981 |
| transect sampling to enhance efficiency of corn rootworm (coleoptera: chrysomelidae) monitoring in corn. | crop monitoring for adult corn rootworms, diabrotica virgifera virgifera leconte and diabrotica barberi smith and lawrence, remains the best means to assess fields at risk from this pest if replanted to corn, zea mays (l.). improvements in sampling methodology, including the development of a sequential sampling plan, have reduced the minimum sampling time required to make a management decision to 20 min or less per field per visit. however, many growers and crop consultants still find this time ... | 2003 | 14650514 |
| a spatially explicit model simulating western corn rootworm (coleoptera: chrysomelidae) adaptation to insect-resistant maize. | a stochastic spatially explicit computer model is described that simulates the adaptation by western corn rootworm, diabrotica virgifera virgifera leconte, to rootworm-resistance traits in maize. the model reflects the ecology of the rootworm in much of the corn belt of the united states. it includes functions for crop development, egg and larval mortality, adult emergence, mating, egg laying, mortality and dispersal, and alternative methods of rootworm control, to simulate the population dynami ... | 2003 | 14650529 |
| larval susceptibility of an insecticide-resistant western corn rootworm (coleoptera: chrysomelidae) population to soil insecticides: laboratory bioassays, assays of detoxification enzymes, and field performance. | soil insecticides were evaluated in laboratory and field studies against larvae of an insecticide resistant population (phelps county, ne) of western corn rootworm, diabrotica virgifera virgifera leconte. insecticide toxicity was evaluated by topical application of technical insecticides to 3rd instars from saunders county, ne (susceptible) and phelps county populations. resistance ratios (ld50 phelps county/ld50 saunders county) for the insecticides methyl parathion, tefluthrin, carbofuran, ter ... | 2000 | 14658504 |
| basic biology and small-scale rearing of celatoria compressa(diptera: tachinidae), a parasitoid of diabrotica virgifera virgifera (coleoptera: chrysomelidae). | the tachinid celatoria compressa wulp has been evaluated as a candidate biological control agent for the western corn rootworm, diabrotica virgifera virgiferaleconte, in europe, where it is an invasive alien pest of maize. special emphasis has been placed on understanding aspects of the parasitoid basic biology and on developing a rearing technique for a small-scale production of c. compressapuparia. the age of c. compressa adults was found to be the most crucial factor in achieving mating. only ... | 2003 | 14704104 |
| use of transgenic plants to measure insect herbivore movement. | use of ingested transgenic corn tissue as a marker for measuring movement of adult diabrotica virgifera virgifera (leconte) (coleoptera: chrysomelidae; western corn rootworm) was investigated. laboratory observations of beetles feeding on corn foliage, pollen, silks, or soybean foliage provided background on feeding patterns. the interval between food consumption and its appearance in feces (gut passage time) ranged from 102.7 +/- 11 min for soybean foliage to 56.7 +/- 2.9 min for corn silks. in ... | 2003 | 14977111 |
| in-field labeling of western corn rootworm adults (coleoptera: chrysomelidae) with rubidium. | field and laboratory studies were conducted in 2000 and 2001 to determine the feasibility of mass marking western corn rootworm adults, diabrotica virgifera virgifera leconte, with rbcl in the field. results showed that application of rubidium (rb) in solution to both the soil (1 g rb/plant) and whorl (1 g rb/plant) of corn plants was optimal for labeling western corn rootworm adults during larval development. development of larvae on rb-enriched corn with this technique did not significantly in ... | 2003 | 14977112 |
| characterization of general esterases from methyl parathion-resistant and -susceptible populations of western corn rootworm (coleoptera: chrysomelidae). | a consistent correlation between elevated esterase activity and methyl parathion resistance among nebraska western corn rootworm, diabrotica virgifera virgifera leconte, populations has previously been documented. characterization of general esterase activity using naphtholic esters as model substrates indicated that differences between resistant and susceptible strains could be maximized by optimizing assay conditions. the optimal conditions identified here were similar to those reported for ot ... | 2003 | 14977127 |
| economics versus alleles: balancing integrated pest management and insect resistance management for rotation-resistant western corn rootworm (coleoptera: chrysomelidae). | western corn rootworm, diabrotica virgifera virgifera leconte, has overcome crop rotation in several areas of the central united states. we expanded a simple model of adult behavior and population genetics to explain how rotation resistance may have developed and to study ways to manage the western corn rootworm in a landscape of corn, soybean, and winter wheat where evolution of resistance may occur. we modeled six alternative management strategies over a 15-yr time horizon, as well as a strate ... | 2003 | 14977129 |
| characterisation of cysteine proteinases responsible for digestive proteolysis in guts of larval western corn rootworm (diabrotica virgifera) by expression in the yeast pichia pastoris. | cysteine proteinases are the major class of enzymes responsible for digestive proteolysis in western corn rootworm (diabrotica virgifera), a serious pest of maize. a larval gut extract hydrolysed typical cathepsin substrates, such as z-phe-arg-amc and z-arg-arg-amc, and hydrolysis was inhibited by z-phe-tyr-dmk, specific for cathepsin l. a cdna library representing larval gut tissue mrna contained cysteine proteinase-encoding clones at high frequency. sequence analysis of 11 cysteine proteinase ... | 2004 | 15041015 |
| entomopathogenic nematodes in the european biocontrol market. | in europe total revenues in the biocontrol market have reached approximately 200 million euros. the sector with the highest turn-over is the market for beneficial invertebrates with a 55% share, followed by microbial agents with approximately 25%. annual growth rates of up to 20% have been estimated. besides microbial plant protection products that are currently in the process of re-registration, several microbial products have been registered or are in the process of registration, following the ... | 2003 | 15149088 |
| introduction of diabrotica virgifera virgifera into the old world and its consequences: a recently acquired invasive alien pest species on zea mays from north america. | diabrotica v. virgifera leconte (coleoptera: chrysomelidae), (in short d.v.v.), with common name western corn rootworm, is endemic to the new world. originating in the regions from south america to mexico where it was in biological equilibrium with its natural enemies, predators and pathogens, it moved north with its food plants. probably due to human agricultural farm practices with preference for monoculture of maize, the insect found open niches for expanding to the midwestern us where lecont ... | 2003 | 15149091 |
| effects of different growing systems and fertiliser rates on attractiveness of maize crop to beetles of diabrotica virgifera virgifera leconte and larvae dammage. | monitoring of plant lodging, yield reaction due to root injures caused by western corn rootworm larvae (wcr) (diabroticia virgifera virgifera le conte) and adults abundance with yellow multigard and pherocone am and pheromone csalomon traps, were performed in three field trials. first one with 4 variants of maize growing system; maize continuous cropping, two crop rotation (wheat-maize, soybean-maize) and three crop rotation (wheat-soybean-maize), set up in 1985. second one with 54 variants, bot ... | 2003 | 15149092 |
| a monitoring trap for diabrotica virgifera virgifera and d. barberi adults lured with a poisoned cucurbitacin bait. | a trap is described that uses as a simple natural ingredient a cucurbitacin mixture to capture and carbaryl insecticide to kill northern and western corn rootworm beetles (diabrotica barberi smith and lawrence, and diabrotica virgifera virgifera leconte (d.v.v.), respectively). the trap is consistent in numbers of beetles captured per trap per day, and it should be useful in integrated pest management programs to monitor the population density of rootworm beetles in corn fields. captures between ... | 2003 | 15149093 |
| time of planting and choice of maize hybrids in controlling wcr (diabrotica virgifera virgifera le conte) in serbia and montenegro. | effects of the length of growing season of maize hybrids (fao maturity groups 400, 500, 600 and 700) and planting dates on the maize crop, as an attractive supplemental feeding for western corn rootworm (wcr) beetles and larval survival, were observed in two locations of south banat, during a three-year (1997-1999) and a two-year period (2001 and 2002). the feeding attraction of the maize crop for wcr beetles and survival of larvae were evaluated in dependency of the variable "plant lodging". th ... | 2003 | 15149095 |
| distribution patterns of mca-coated granules aerially applied to corn fields of southern hungary between 2000 and 2002. | field studies in corn (zea mays l.) were conducted to evaluate distribution patterns of 4-methoxy-cinnamaldehyde (mca) coated corn grits after aerial application with a dromader fixed wing aircraft. the kairomone mimic mca is synthetically available and a quite specific and efficient adult attractant for the invasive alien maize pest western corn rootworm (wcr) diabrotica virgifera virgifera leconte. orientation disruptive properties of mca for wcr when applied at unphysiologically high concentr ... | 2003 | 15149096 |
| orientation disruption of diabrotica virgifera virgifera in maize by a liquid mca formulation released from paper squares in the banat region of serbia and montenegro. | serbia-montenegro, formerly the republic of yugoslavia, is the first european country where diabrotica virgifera virgifera le conte (col.: chrysomelidae) (d.v.v.) was reported in 1992 as an invasive alien pest species, baca (1993), camprag and baca, (1995): from a focal point near belgrade airport, the maize pest quickly spread in all directions reaching the economic threshold in a number of surrounding countries around 1995. the field experiments described took place in the banat region east of ... | 2003 | 15149097 |
| disruption of host location of western corn rootworm larvae (coleoptera: chrysomelidae) with carbon dioxide. | elevated concentrations of carbon dioxide (co2) prevented neonate larvae of the western corn rootworm, diabrotica virgifera virgifera leconte, from locating the roots of growing corn in behavioral bioassays conducted in soil tubs. when co2 was pumped into one end of a soil tub, significantly more larvae were recovered from soil at the treated end than from soil around a growing corn plant at the opposite end of the tub. in controls with ambient air pumped into one end of a soil tub, significantl ... | 2004 | 15154452 |
| ovarian development and ovipositional preference of the western corn rootworm (coleoptera: chrysomelidae) variant in east central illinois. | the rotation of maize, zea mays l., and soybean, glycine max (l.) merr., has been the traditional cultural tactic to manage the western corn rootworm, diabrotica virgifera virgifera leconte, in the corn belt. the reduced effectiveness of this rotation as a pest management tool in east central illinois, northern indiana, and southern michigan can be explained by the shift in the ovipositional behavior of the new variant of western corn rootworm. the objective of this study was to evaluate the inf ... | 2004 | 15154460 |
| population patterns of mexican corn rootworm (coleoptera: chrysomelidae) adults indicated by different sampling methods. | the mexican corn rootworm, diabrotica virgifera zeae krysan & smith, is a serious pest of corn, zea mays l., in several areas of texas. recent demonstrations of areawide adult control suggest this tactic has promise for rootworm management, but additional information regarding treatment thresholds and sampling methodology is needed. in 2000 and 2001 we examined the influence of distance into the field on rootworm captures by crw and pherocon am traps, the fidelity of trap captures to population ... | 2004 | 15154499 |
| role of egg density on establishment and plant-to-plant movement by western corn rootworm larvae (coleoptera: chrysomelidae). | the effect of egg density on establishment and dispersal of larvae of the western corn rootworm, diabrotica virgifera virgifera leconte, was evaluated in a 3-yr field study. implications of these data for resistance management plans for bt crops are discussed. viable egg levels of 100, 200, 400, 800, and 1600 eggs per infested plant were evaluated in 2000, 2001, and 2002. a 3200 viable egg level was also tested in 2001 and 2002. all eggs were infested on one plant per subplot in a field that was ... | 2004 | 15279266 |
| binary toxins from bacillus thuringiensis active against the western corn rootworm, diabrotica virgifera virgifera leconte. | the western corn rootworm, diabrotica virgifera virgifera leconte, is a significant pest of corn in the united states. the development of transgenic corn hybrids resistant to rootworm feeding damage depends on the identification of genes encoding insecticidal proteins toxic to rootworm larvae. in this study, a bioassay screen was used to identify several isolates of the bacterium bacillus thuringiensis active against rootworm. these bacterial isolates each produce distinct crystal proteins with ... | 2004 | 15294828 |
| a novel bacillus thuringiensis (ps149b1) containing a cry34ab1/cry35ab1 binary toxin specific for the western corn rootworm diabrotica virgifera virgifera leconte forms ion channels in lipid membranes. | the binary bacillus thuringiensis ps149b1 insecticidal crystal (cry) protein is comprised of two components, cry34ab1, a 14-kda protein, and cry35ab1, a 44-kda protein, the combination of which forms a novel binary toxin active on western corn rootworm larvae. the permeabilizing behavior of the native binary toxin and its two individual components expressed as recombinant proteins was studied using calcein efflux determination in liposomes and by ion channel activity measurements in planar lipid ... | 2004 | 15379574 |
| response of larvae of invasive maize pest diabrotica virgifera virgifera (coleoptera: chrysomelidae) to carbon/nitrogen ratio and phytosterol content of european maize varieties. | we studied the performance of larvae of diabrotica virgifera virgifera leconte (chrysomelidae, galerucinae) on 17 different maize, zea mays l., varieties from six european countries. food conversion efficiency studies were performed using a newly established method. the growth of d. v. virgifera (western corn rootworm) larvae and the amount of ingested food was measured and the food conversion efficiency was calculated. in addition, we analyzed the carbon/nitrogen ratio and the phytosterol conte ... | 2004 | 15384346 |
| monitoring western corn rootworm (coleoptera: chrysomelidae) susceptibility to carbaryl and cucurbitacin baits in the areawide management pilot program. | areawide pest management involves the uniform application of a pest control strategy over wide geographic areas. therefore, these programs are likely to impose intense selective pressures, and the risk for resistance development among pest species for which areawide management programs are implemented is likely to be high. pilot studies for areawide management of western corn rootworm, diabrotica virgifera virgifera leconte, were conducted from 1996 to 2002 at four different sites across the cor ... | 2004 | 15568365 |
| immunological assessment of an insecticide resistance-associated esterase in the western corn rootworm. | in previous investigations, we have determined that organophosphate resistance in the western corn rootworm, diabrotica virgifera virgifera, is at least partially attributed to a group of non-specific carboxylesterases referred to as group ii. antiserum raised against a purified 66-kda group ii esterase is specific for the denatured enzyme. this antiserum reacts similarly with both beetle homogenates from resistant and susceptible populations, although there is much higher signal intensity in im ... | 2005 | 15717320 |
| effective control method of larvae of diabrotica virgifera virgifera leconte. | larvae of wcr are feeding on the roots of corn while plants fall down. the egg hatching is continuous and soil insecticides are not effective to kill larvae. unfortunately the recent control methods while we incorporate disinfectors into the soil under seeding are not able to give enough effect on larvae of wcr under the whole period of larval development. we use to saw corn in the middle of april but eggs hatching start in the middle of may. the effectiveness of insecticides takes about one mon ... | 2004 | 15759402 |
| first report of the western corn rootworm diabrotica virgifera in belgium. | 2004 | 15759426 | |
| expressed sequence tags from diabrotica virgifera virgifera midgut identify a coleopteran cadherin and a diversity of cathepsins. | the western corn rootworm is the major pest of corn in the usa and has recently become the target for insect-resistant transgenic crops. transgenic crops have switched the focus for identifying insecticide targets from the insect nervous system to the midgut. here we describe a collection of 691 sequences from the western corn rootworm midgut, 27% of which predict proteins with no matches in current databases. of the remaining sequences, most predict proteins with either catalytic (62%) or bindi ... | 2005 | 15796746 |
| characterization of cry34/cry35 binary insecticidal proteins from diverse bacillus thuringiensis strain collections. | bacillus thuringiensis crystal proteins of the cry34 and cry35 classes function as binary toxins showing activity on the western corn rootworm, diabrotica virgifera virgifera leconte. we surveyed 6,499 b. thuringiensis isolates by hybridization for sequences related to cry35a genes, identifying 78 strains. proteins of the appropriate molecular mass (ca. 44 kda) for cry35 were observed in 42 of the strains. full-length, or nearly full-length, sequences of 34 cry34 genes and 16 cry35 genes were al ... | 2005 | 15811999 |
| recruitment of entomopathogenic nematodes by insect-damaged maize roots. | plants under attack by arthropod herbivores often emit volatile compounds from their leaves that attract natural enemies of the herbivores. here we report the first identification of an insect-induced belowground plant signal, (e)-beta-caryophyllene, which strongly attracts an entomopathogenic nematode. maize roots release this sesquiterpene in response to feeding by larvae of the beetle diabrotica virgifera virgifera, a maize pest that is currently invading europe. most north american maize lin ... | 2005 | 15815622 |
| analysis of the dynamics of adaptation to transgenic corn and crop rotation by western corn rootworm (coleoptera: chrysomelidae) using a daily time-step model. | western corn rootworm, diabrotica virgifera virgifera leconte, has overcome crop rotation in several areas of the north central united states. the effectiveness of crop rotation for management of corn rootworm has begun to fail in many areas of the midwestern united states, thus new management strategies need to be developed to control rotation-resistant populations. transgenic corn, zea mays l., effective against western corn rootworm, may be the most effective new technology for control of thi ... | 2005 | 15889747 |
| effectiveness of recombinant soybean cysteine proteinase inhibitors against selected crop pests. | three recombinant soybean cysteine proteinase inhibitors (rscpis), l1, r1 and n2, were assessed for their potential to inhibit the growth and development of three major agricultural crop pests known to utilize digestive cysteine proteinases: western corn rootworm (diabrotica virgifera virgifera, wcr), colorado potato beetle (leptinotarsa decemlineata, cpb) and cowpea weevil (callosobruchus maculatus, cw). in vitro experiments showed that cysteine proteinase activities in the crude gut extracts o ... | 2005 | 15907768 |
| economic analysis of dynamic management strategies utilizing. transgenic corn for control of western corn rootworm (coleoptera: chrysomelidae). | we studied management strategies for western corn rootworm, diabrotica virgifera virgifera leconte, using transgenic corn, zea mays l., from both a biological and an economic perspective. in areas with and without populations adapted to a 2-yr rotation of corn and soybean (rotation-resistant), the standard management strategy was to plant 80% of a cornfield (rotated and continuous) to a transgenic cultivar each year. in each area, we also studied dynamic management strategies where the proportio ... | 2005 | 16022329 |
| effect of cry3bb1-expressing transgenic corn on plant-to-plant movement by western corn rootworm larvae (coleoptera: chrysomelidae). | dispersal of larvae of the western corn rootworm, diabrotica virgifera virgifera leconte, in specific combinations of transgenic corn expressing the cry3bb1 protein and nontransgenic, isoline corn was evaluated in a 2-yr field study. in total, 1,500 viable western corn rootworm eggs were infested in each subplot. each year, plant damage and larval recovery were evaluated among four pedigree combinations (straight transgenic; straight nontransgenic corn; nontransgenic corn with a transgenic centr ... | 2005 | 16156562 |
| insecticide enhancement with feeding stimulants in corn for western corn rootworm larvae (coleoptera: chrysomelidae). | amounts of the insecticide thiamethoxam required for 50% mortality of western corn rootworm larvae, diabrotica virgifera virgifera leconte, were reduced 100-fold when extracts of germinating corn, zea mays l., were used to entice neonate larvae to feed on it. in behavioral bioassays, neonate rootworm larvae fed vigorously on filter paper disks treated with liquid pressed from corn roots. moreover, disks treated with an acetone extract of corn (dried and rewetted with water) also elicited strong ... | 2005 | 16156565 |
| flight behavior of methyl-parathion-resistant and -susceptible western corn rootworm (coleoptera: chrysomelidae) populations from nebraska. | relative flight behavior of methyl-parathion-resistant and -susceptible western corn rootworm, diabrotica virgifera virgifera leconte populations, was studied as part of a larger effort to characterize the potential impact of insecticide resistance on adult life history traits and to understand the evolution and spread of resistance. a computer interfaced actograph was used to compare flight of resistant and susceptible individuals, and flight of resistant individuals with and without prior expo ... | 2005 | 16156583 |
| baseline susceptibility of western corn rootworm (coleoptera: crysomelidae) to cry3bb1 bacillus thuringiensis toxin. | susceptibility to cry3bb1 toxin from bacillus thuringiensis (bt) was determined for western corn rootworm, diabrotica virgifera virgifera leconte, neonates from both laboratory and field populations collected from across the corn belt. rootworm larvae were exposed to artificial diet treated with increasing cry3bb1 concentrations, and mortality and growth inhibition were evaluated after 4-7 d. the range of variation in bt susceptibility indicated by growth inhibition was similar to that indicated ... | 2005 | 16156586 |
| screening of entomopathogenic nematodes for virulence against the invasive western corn rootworm, diabrotica virgifera virgifera (coleoptera: chrysomelidae) in europe. | entomopathogenic nematode species available in europe were screened for their efficacy against both the root-feeding larvae and silk-feeding adults of the western corn rootworm, diabrotica virgifera virgifera leconte. laboratory screening tests were aimed at the selection of candidate biological control agents for the management of this invasive alien pest in europe. steinernema glaseri, s. arenarium, s. abassi, s. bicornutum, s. feltiae, s. kraussei, s. carpocapsae and heterorhabditis bacteriop ... | 2005 | 16197568 |
| effect of four cropping systems on variant western corn rootworm (coleoptera: chrysomelidae) adult and egg densities and subsequent larval injury in rotated maize. | the cultural practice of rotating corn, zea mays l., with soybean, glycine max (l.) merrill, to manage larval injury by the western corn rootworm, diabrotica virgifera virgifera leconte, was used extensively throughout east central illinois and northern indiana until the mid-1990s. the effectiveness of this management tactic diminished due to a shift in the ovipositional behavior of the western corn rootworm. the variant western corn rootworm has since spread as far as northwestern illinois, sou ... | 2005 | 16334328 |
| western corn rootworm (coleoptera: chrysomelidae) beetle emergence from weedy cry3bbl rootworm-resistant transgenic corn. | three greenhouse experiments were conducted to evaluate western corn rootworm, diabrotica virgifera virgifera leconte, beetle emergence from individual pots containing glyphosate-tolerant transgenic corn, zea mays l., expressing the cry3bbl endotoxin from the soil bacterium bacillus thuringiensis berliner (mon863), nontransgenic glyphosate-tolerant isoline corn, grassy weeds (giant foxtail, setariafaberi r.a.w. herrm; and large crabgrass, digitaria sanguinalis (l.) scop.), and combinations there ... | 2005 | 16334339 |
| discovery and characterization of sip1a: a novel secreted protein from bacillus thuringiensis with activity against coleopteran larvae. | bioassay screening of bacillus thuringiensis culture supernatants identified strain eg2158 as having larvicidal activity against colorado potato beetle (leptinotarsa decemlineata) larvae. ion-exchange fractionation of the eg2158 culture supernatant resulted in the identification of a protein designated sip1a (secreted insecticidal protein) of approximately 38 kda having activity against colorado potato beetle (cpb). an oligonucleotide probe based on the n-terminal sequence of the purified sip1a ... | 2006 | 16489451 |
| evaluation of cuphea as a rotation crop for control of western corn rootworm (coleoptera: chrysomelidae). | the ability to prevent significant root feeding damage to corn, zea mays l., by the western corn rootworm, diabrotica virgifera virgifera leconte, by crop rotation with soybean, glycine max (l.) merr., has been lost in portions of the corn belt because this pest has adapted to laying eggs in soybean fields. cuphea spp. has been proposed as a new broadleaf crop that may provide an undesirable habitat for rootworm adults because of its sticky surface and therefore may reduce or prevent oviposition ... | 2005 | 16539123 |
| comparative susceptibility of western corn rootworm (coleoptera: chrysomelidae) adults to selected insecticides in kansas. | susceptibility of adult populations of the western corn rootworm, diabrotica virgifera virgifera leconte, to several insecticides was evaluated in seven kansas counties, including dickinson, ford, finney, pottawatomie, republic, riley, and stevens, between 1996 and 2002. all populations surveyed were highly susceptible to methyl parathion with the largest difference in susceptibility of only three-fold based on 16 complete bioassays for the populations from six counties over a 5-yr period. notic ... | 2005 | 16539149 |
| a promising biotechnical approach to pest management of diabrotica virgifera virgifera in illinois maize fields under kairomonal shielding with the new msd technique. | environmentally compatible and sustainable plant protection requires novel approaches to pest management characterized by minimal emphasis on toxicants. classical toxicants traditionally dominated economic entomology for half a century. but worldwide problems with environmental pollution and with increasing resistance levels in all major pesticide classes and in many key insect species including diabrotica virgifera virgifera (d.v.v.) strongly advocate a rethinking and a change in management par ... | 2005 | 16628896 |
| the western corn rootworm diabrotica virgifera virgifera en route to germany. | the western corn rootworm diabrotica virgifera virgifera leconte (col.:chrysomelidae) (d.v.v.) is one of the most important maize pests in north america. ever since its invasion into europe and its detection near belgrade airport by baca in 1993 it quickly spread all over southeastern europe and is now advancing towards central europe. up until summer 2004 considered free of d.v.v., germany is, with the exception of its northern and northeastern borders, surrounded by countries with proven d.v.v ... | 2005 | 16628903 |
| monitoring presence and advance of the alien invasive western corn rootworm beetle in eastern slovenia with highly sensitive metcalf traps. | the american chrysomelid beetle diabrotica virgifera virgifera leconte (d.v.v.), also called the western corn rootworm, spread from the location of its original introduction into europe, belgrade airport (baca 1993), in all directions. within a decade it occupied almost all countries of south-eastern and central europe. however, it reached slovenia as late as 2003: only 19 specimen were found in maize fields of the eastern and also western provinces. already in the summer of 2004, their number h ... | 2005 | 16628904 |
| quick scouting of eggs of western corn rootworm (diabrotica virgifera virgifera leconte, 1868) from soil. | main method to control the american corn rootworm is crop rotation (camprag et. al., 1994) but we don't know how to determine the possible number of larvae under fall so we cannot use autumn cereals to change the row of cultivated plants. the pest spends almost 10 months in soil in egg and larval state (chiang, 1973). there are two methods for scouting diabrotica eggs and larval instars from soil over the winter. one of the two most important methods is holding soil samples on fixed temperature ... | 2005 | 16628905 |
| assessing risk of resistance to aerial applications of methyl-parathion in western corn rootworm (coleoptera: chrysomelidae). | we validated a stochastic model of the evolution of resistance to adulticidal sprays of methyl-parathion in western corn rootworm, diabrotica virgifera virgifera leconte, populations in nebraska. the population dynamics predicted by the model resembled that reported for field populations, and time until control failures occurred closely matched reports by commercial crop consultants. we incorporated uncertainty about the values used for 18 model parameters by replacing default values with random ... | 2006 | 16686151 |
| absence of genetic divergence between western corn rootworms (coleoptera: chrysomelidae) resistant and susceptible to control by crop rotation. | the western corn rootworm, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae), is a major pest of corn, zea mays l., in north america that has recently invaded europe. a loss of ovipositional fidelity to cornfields has allowed the species to circumvent crop rotation as a means of control in part of its range in the united states. analyses of variation at eight microsatellite loci provided no evidence for general genetic differentiation between samples of western corn rootworm col ... | 2006 | 16813299 |
| diabrotica virgifera virgifera (coleoptera: chrysomelidae) larval feeding behavior on transgenic maize (mon 863) and its isoline. | diabrotica species (coleoptera: chrysomelidae) larval behavior studies have posed a challenge to researchers because of the subterranean life cycle of this pest. to fully understand how the western corn rootworm, diabrotica virgifera virgifera leconte, injures the maize, zea mays l., root system, its behavior must be studied. for example, larvae that can detect an area of the root that has a lower amount of toxin, whether from an insecticide or a transgenic maize plant, have an increased chance ... | 2006 | 16813304 |
| planting transgenic insecticidal corn based on economic thresholds: consequences for integrated pest management and insect resistance management. | a simulation model of the western corn rootworm, diabrotica virgifera virgifera leconte, was used to investigate whether sampling and economic thresholds can improve integrated pest management (ipm) and insect resistance management (irm) when transgenic insecticidal crops are used for insect pest management. when transgenic corn killed at least 80% of susceptible larvae, the calculated economic threshold increased linearly as the proportion of susceptible beetles surviving the toxin increased. t ... | 2006 | 16813328 |
| effect of bacillus thuringiensis cry3bb1 protein on the feeding behavior and longevity of adult western corn rootworms (coleoptera: chrysomelidae). | the first transgenic corn hybrids expressing the bacillus thuringiensis (bt) cry3bb1 protein to control corn rootworm (diabrotica spp.) larvae were registered for commercial use in 2003. this study was conducted to investigate the effect of cry3bb1 protein in combination with a cucurbitacin bait on adult feeding and longevity of both organophosphate-resistant and -susceptible western corn rootworms, diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae). in choice and no-choice tests ... | 2006 | 16813332 |
| adult movements of newly introduced alien diabrotica virgifera virgifera (coleoptera: chrysomelidae) from non-host habitats. | mark-release-recapture experiments were undertaken in order to investigate the movement of adult diabrotica virgifera virgifera leconte from accidental introduction points towards suitable habitats, such as its host plant, zea mays l. in hungary in 2003 and 2004, nine mark-release-recapture experiments were carried out in a grass steppe area and lucerne field, in which two small maize fields (10x10 m) had been planted 300 m distant from the central release point. after each release of 5500 to 60 ... | 2006 | 16923199 |
| field measures of western corn rootworm (coleoptera: chrysomelidae) mortality caused by cry34/35ab1 proteins expressed in maize event 59122 and implications for trait durability. | maize, zea mays l., has been transformed to express the cry34ab1 and cry35ab1 proteins from bacillus thuringiensis strain ps149b1. these two proteins act together as a binary insecticidal protein that is effective against corn rootworm (coleoptera: chrysomelidae) species. the design of the resistance management plan to preserve the long-term durability of this trait largely depends on the level of rootworm mortality induced by cry34/35ab1 corn rootworm-protected maize (frequently referred to as ... | 2006 | 16937696 |
| an isorhamnetin rhamnoglycoside serves as a costimulant for sugars and amino acids in feeding responses of adult western corn rootworms (diabrotica virgifera virgifera) to corn (zea mays) pollen. | adult beetles of diabrotica virgifera virgifera leconte (western corn rootworm) feed on pollen of zea mays l. (corn) and other plant species. to identify d. virgifera feeding stimulants, beetle responses to mixtures of known and novel phagostimulants, presented at their naturally occurring concentrations in maize pollen, were compared to individual component responses applying the amount occurring in 0.2 mg of pollen per cellulose feeding disk. on a molar basis, three major sugars (fructose, glu ... | 2007 | 17268822 |
| diabrotica virgifera virgifera in switzerland: future invasion trend into germany via transalpine, terrestrial routes. | the western corn rootworm diabrotica v.virgifera (d.v.v.) (coleoptera:chrysomelidae) is endemic to the new world. on at least 3 occasions, it invaded europe (miller et al. 2005). the first of these invasions took place in or before 1992 (baca 1993) to belgrade, serbia, and gave rise to a rapidly expanding beetle population in se europe. its larvae are causing economic damage to zea mays for the last ten years, with increasing severity both in acreage and density. meanwhile germany is still witho ... | 2006 | 17385500 |
| diabrotica virgifera virgifera in eastern slovenia: increasing population trend 2005. | the first invasion of the western corn rootworm (wcr), diabrotica virgifera virgifera leconte (coleoptera: chrysomelidae) into slovenia was recorded in 2003. a few beetles were found in the western province of slovenia near italy. more beetles were detected in the eastern district of prekmurje bordering austria, hungary and croatia. while the western population remained the same in 2005, the eastern population increased considerably. by means of the very sensitive metcalf sticky trap baited with ... | 2006 | 17385526 |
| diabrotica flight in time and space as monitored with a high capacity trap placed in zea mays fields of illinois, usa. | monitoring of insects by trapping is one of the prime tools of field entomologists. the leaf beetle diabrotica virgifera virgifera leconte (coleoptera:chrysomelidae) is no exception. since its numbers (and consequently its mass) in a field population can be enormous, tools must be adapted to hold this many insects for later counting, sexing, biomass determinations, and additional investigations to follow. since counting the high numbers during the flight peak may not be feasible at all, weighing ... | 2006 | 17385527 |