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Entomology Commons™

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2004

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Articles 91 - 112 of 112

Full-Text Articles in Entomology

Atrazine Induction Of A Family 4 Cytochrome P450 Gene In Chironomus Tentans (Diptera: Chironomidae), Diana K. Londono, Blair D. Siegfried, Michael J. Lydy Jan 2004

Atrazine Induction Of A Family 4 Cytochrome P450 Gene In Chironomus Tentans (Diptera: Chironomidae), Diana K. Londono, Blair D. Siegfried, Michael J. Lydy

Department of Entomology: Faculty Publications

Cytochrome P450-dependent microsomal monooxygenase (P450) activity was measured in control and atrazine-exposed third instar midge larvae, Chironomus tentans. Significantly elevated O-demethylase activity was observed in gut homogenates taken from midges exposed to atrazine concentrations from 1 to 10 ppm for 90 h. No significant induction was observed at atrazine concentrations below 1 ppm. A region of a cytochrome P450 family 4 gene was amplified and sequenced from C. tentans larvae. Alignments of inferred amino acid sequences with other insect CYP4 gene homologues indicate a high degree of similarity. Northern blot analysis employing the CYP4 gene fragment as a …

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Within-Field Distribution Of The Sunflower Midge (Diptera: Cecidomyiidae), E. W. Hodgson, I. V. Macrae, Gary J. Brewer Jan 2004

Within-Field Distribution Of The Sunflower Midge (Diptera: Cecidomyiidae), E. W. Hodgson, I. V. Macrae, Gary J. Brewer

Department of Entomology: Faculty Publications

The sunßower midge, Contarinia schulzi Gagne (Diptera: Cecidomyiidae), is a pest of cultivated sunflower (Helianthus annuus L.). Larval feeding can cause damage and yield loss to the sunflower head. Adult emergence is extended and larvae are well protected in the sunflower receptacle, making chemical control methods difficult and expensive. Sunflower midge enter sunflower fields at the edges but fieldwide distributions occur, although the dynamics are not fully understood. Two commercial fields in 1999 and one field in 2000 were systematically sampled by dividing each field into fixed sample points. Mean egg and larval densities from each sample point were …

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Flight Muscle–Specific Expression Of Act88f: Gfp In Transgenic Culex Quinquefasciatus Say (Diptera: Culicidae), Margaret L. Allen, Bruce M. Christensen Jan 2004

Flight Muscle–Specific Expression Of Act88f: Gfp In Transgenic Culex Quinquefasciatus Say (Diptera: Culicidae), Margaret L. Allen, Bruce M. Christensen

Department of Entomology: Faculty Publications

A strategy to engineer a strain of Culex mosquitoes refractory to filarial transmission is described. A requirement for success of the strategy is identification of a flight muscle–specific promoter that functions in the mosquito. A GFP marker gene under the control of the promoter region of the Drosophila melanogaster act88F gene was inserted into the genome of Culex quinquefasciatus. Transformation was confirmed by Mendelian genetics. Hy-bridization of a genomic Southern blot to a radiolabeled probe verified that the entire donor plasmid integrated into the mosquito genome. GFP expression in the transgenic mosquitoes was restricted to the flight muscles.

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Supercooling Differences In The Eastern Subterranean Termite (Isoptera: Rhinotermitidae), Brian J. Cabrera, Shripat T. Kamble Jan 2004

Supercooling Differences In The Eastern Subterranean Termite (Isoptera: Rhinotermitidae), Brian J. Cabrera, Shripat T. Kamble

Department of Entomology: Faculty Publications

Supercooling points were determined for untreated field-collected and untreated laboratory-maintained Reticulitermes flavipes (Kollar) workers and soldiers. Workers treated with antibiotics or had their hindgut-protozoa removed by exposing them to oxygen under pressure to determine the effects of absence of the hindgut fauna on supercooling. Supercooling points were compared be-tween live and freshly killed workers to determine whether supercooling in this species might be simply due to the biochemical properties of body fluids. Laboratory-maintained workers were also subjected to desiccation, starvation, or atmospheric pressure to determine their effects on supercool-ing. Supercooling points were lowest for laboratory workers treated with antibiotics and …

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Molecular Differentiation Of Two Sibling Species Of The Black Fly Simulium Vittatum (Diptera: Simuliidae) Based On Random Amplified Polymorphic Dna, G. A. Duncan, P. H. Alder, K. P. Pruess, T. O. Powers Jan 2004

Molecular Differentiation Of Two Sibling Species Of The Black Fly Simulium Vittatum (Diptera: Simuliidae) Based On Random Amplified Polymorphic Dna, G. A. Duncan, P. H. Alder, K. P. Pruess, T. O. Powers

Department of Entomology: Faculty Publications

Larvae of the black fly morphospecies Simulium vittatum from Colorado, Montana, Nebraska, and New Hampshire were cytologically identified as either the IS-7 or the IIIL-1 cytospecies. DNA was PCR amplified from cytotyped larvae using eight 10-mer primers, labeled with 33P, and run on pol-yacrylamide gels. The entire data set of 96 amplicons produced incomplete separation of the two cytospecies when subjected to neighbor-joining and maximum parsimony analyses. However, when analyzed within geographical regions, separate species status was supported. Bootstrap support for distinctness of the two cytospecies was best in Colorado where they were collected in true sympatry. The IS-7 cytospecies …

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Impact Of Ceutorhynchus Litura Feeding On Root Carbohydrate Levels In Canada Thistle (Cirsium Arvense), Gary L. Hein, Robert G. Wilson Jan 2004

Impact Of Ceutorhynchus Litura Feeding On Root Carbohydrate Levels In Canada Thistle (Cirsium Arvense), Gary L. Hein, Robert G. Wilson

Department of Entomology: Faculty Publications

Canada thistle is a serious perennial weed found throughout the northern regions of the United States and Canada. The weevil, Ceutorhynchus litura (F.), was first released in Canada in 1965 as a potential biological control agent for Canada thistle; however, its impact as a control agent has been sporadic. The objective of this study was to characterize C. litura impacts on the carbohydrate profile in Canada thistle roots through the growing season and to evaluate the potential for this biological control agent in causing stress to Canada thistle. Field plots, infested with C. litura, were established and extensively sampled …

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Alfalfa: Simulated Clover Leaf Weevil Injury And Alfalfa Yield And Quality, Rodney A. Madsen, Thomas E. Hunt, Leon G. Higley Jan 2004

Alfalfa: Simulated Clover Leaf Weevil Injury And Alfalfa Yield And Quality, Rodney A. Madsen, Thomas E. Hunt, Leon G. Higley

Department of Entomology: Faculty Publications

The clover leaf weevil (Hypera punctata F.) is a sporadic but potentially serious pest of alfalfa (Medicago sativa L.). Feeding of newly emerged adult fourth instar clover leaf weevil was simulated in a field study at the University of Nebraska Haskell Agricultural Research Lab near Concord, Nebraska, in May 2001 and 2002. Twelve 1- by 1-m plots were arranged in a randomized complete block design with three treatments and four replications. Treatments consisted of two levels of simulated clover leaf weevil defoliation of alfalfa and an undefoliated check. Leaflets were removed over 10 d. Dry matter yield and …

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Natural Distribution Of Hymenopteran Parasitoids Of Spodoptera Frugiperda (Lepidoptera: Noctuidae) Larvae In Mexico, Jaime Molina-Ochoa, James E. Carpenter, Roberto Lezama-Gutiérrez, John E. Foster, Martín González-Ramírez, César Andres Angel-Sahagún, Javier Farías-Larios Jan 2004

Natural Distribution Of Hymenopteran Parasitoids Of Spodoptera Frugiperda (Lepidoptera: Noctuidae) Larvae In Mexico, Jaime Molina-Ochoa, James E. Carpenter, Roberto Lezama-Gutiérrez, John E. Foster, Martín González-Ramírez, César Andres Angel-Sahagún, Javier Farías-Larios

Department of Entomology: Faculty Publications

Se llevó a cabo un inventario de parasitoides de larvas del gusano cogollero, Spodoptera frugiperda (J. E. Smith) (FAW) colectadas principalmente de maizales en estado de verticilio en seis estados mexicanos durante Agosto y Septiembre de 2000. Trece géneros de parasitoides himenópteros fueron recuperados, representando a tres familias, Braconidae: Aleoides, Chelonus, Cotesia, Glyptapanteles, Homolobus, y Meteorus); Ichneumonidae: Campoletis, Eiphosoma, Ophion, y Pristomerus; y Eulophidae: Aprostocetus, Euplectrus, y Horismenus. De un total de 5591 larvas colectadas, 772 produjeron parasitoides, para una tasa de parasitismo de 13.8%. La tasa de parasitismo más alta para una colecta simple fué …

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Effect Of Environment On Resistance To The European Corn Borer (Lepidoptera: Crambidae) In Maize, David B. Willmot, Bruce E. Hibbard, Larry L. Darrah, Linda M. Pollak, Kevin Montgomery, Richard C. Pratt, Craig A. Abel, James A. Hawk, Tecle Weldekidan, John E. Foster Jan 2004

Effect Of Environment On Resistance To The European Corn Borer (Lepidoptera: Crambidae) In Maize, David B. Willmot, Bruce E. Hibbard, Larry L. Darrah, Linda M. Pollak, Kevin Montgomery, Richard C. Pratt, Craig A. Abel, James A. Hawk, Tecle Weldekidan, John E. Foster

Department of Entomology: Faculty Publications

The European corn borer, Ostrinia nubilalis (Hu¨ bner) (Lepidoptera: Crambidae), is a major pest of maize, Zea mays L., in many temperate parts of the world. Genotype-by-environment interaction effects can make relative performance unpredictable and may hamper selection for resistance to European corn borer. The objective of this study was to determine the effect of environment on genotypic reaction to European corn borer resistance in maize. A set of 12 maize inbred lines was chosen to represent a range of European corn borer responses. Eleven testing environments ranged from Delaware, Ohio, Illinois, Iowa, Nebraska, Missouri, to Mississippi. For length of …

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Phospholipase A2 In Salivary Glands Isolated From Tobacco Hornworms, Manduca Sexta, Hasan Tunaz, David W. Stanley Jan 2004

Phospholipase A2 In Salivary Glands Isolated From Tobacco Hornworms, Manduca Sexta, Hasan Tunaz, David W. Stanley

Department of Entomology: Faculty Publications

We describe a phospholipase A2 (PLA2) associated with the salivary glands of tobacco hornworms, Manduca sexta. This enzyme is able to hydrolyze arachidonic acid from the sn-2 position of PLs. Addition of the calcium chelator, EGTA, or calcium, to the Tris reaction buffer impaired the PLA2 activity, from which we infer the enzyme requires very low concentrations of calcium or perhaps other ions for optimal activity. PLA2 activity was sensitive to protein concentration (highest activity at 25 μg protein per μl), reaction time (optimal at 30 min), buffer pH (optimal at pH 8–10), …

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An Entomopathogenic Bacterium, Xenorhabdus Nematophila, Inhibits Hemocytic Phospholipase A2 (Pla2) In Tobacco Hornworms, Manduca Sexta, Youngjin Park, Yonggyun Kim, Hasan Tunaz, David W. Stanley Jan 2004

An Entomopathogenic Bacterium, Xenorhabdus Nematophila, Inhibits Hemocytic Phospholipase A2 (Pla2) In Tobacco Hornworms, Manduca Sexta, Youngjin Park, Yonggyun Kim, Hasan Tunaz, David W. Stanley

Department of Entomology: Faculty Publications

The entomopathogenic bacterium, Xenorhabdus nematophila, induces immunodepression in target insects and finally leads to lethal septicemia of the infected hosts. A hypothesis has been raised that the bacteria inhibit eicosanoid-biosynthesis pathway to interrupt immune signaling of the infected hosts. Here, we show direct evidence that X. nematophila inhibits the activity of phospholipase A2 (PLA2), the initial step in the eicosanoid-biosynthesis pathway. Inhibition of PLA2 was dependent on both incubation time with X. nematophila and the bacterial concentration in in vitro PLA2 preparations of Manduca sexta hemocytes. While living bacteria inhibited PLA2 activity, heat-killed X. nematophila rather increased PLA2 activity. X. …

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Acaricidal Efficacy Of Various Agents In The Treatment Of Naturally Occurring Ornithonyssus Sylviarum (Acari: Macronyssidae) Infestations Of Chickens, Maggie Phillips, T. A. Yazwinski, C. A. Tucker, Jennifer Robins, Jeremy Powell, Linda Stamps Jan 2004

Acaricidal Efficacy Of Various Agents In The Treatment Of Naturally Occurring Ornithonyssus Sylviarum (Acari: Macronyssidae) Infestations Of Chickens, Maggie Phillips, T. A. Yazwinski, C. A. Tucker, Jennifer Robins, Jeremy Powell, Linda Stamps

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The northern fowl mite (NFM), Ornithonyssus sylviarum, is a commonly occurring external parasite of chickens. Primarily, caged layers have the greatest incidence of this mite, with bird unrest, unthriftiness and lowered production as some of the adverse effects of the infestation. In the current study, birds with natural NFM infestations were randomized into five treatment groups, placed in individual cages in treatment-specific batteries (all in one room), and evaluated for 28 d for infestation quantification by way of index scoring and feather digest. No treatments were 100% effective in eliminating all life stages of the mite. Tetrachlorvinphos in combination with …

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Host Suitability And Thermal Requirements Of Lathromeris Ovicida Risbec (Hymenoptera: Tricliogrammatidae), An Egg Parasitoid Of Cereal Stemborers In Africa, A. Chabi-Olaye, M. K. Fiaboe, F. Schulthess Jan 2004

Host Suitability And Thermal Requirements Of Lathromeris Ovicida Risbec (Hymenoptera: Tricliogrammatidae), An Egg Parasitoid Of Cereal Stemborers In Africa, A. Chabi-Olaye, M. K. Fiaboe, F. Schulthess

All Peer-Reviewed Publications

Factors affecting the bionomics of the trichogrammatid egg parasitoid Lathromeris ovicida and its association with the two sympatric scelionid egg parasitoids Telenomus busseolae and Telenomus isis were studied in the laboratory. The potential host species employed were the noctuids Sesamia calamistis and Sesamia botanephaga, and the pyralids Eldana saccharina and Mussidia nigrivenella. Using eggs of S. calamistis Hampson as hosts, the lower and upper thresholds for development were estimated at 14.8 and 34°C, respectively. The percent parasitism, total progeny, and sex ratio decreased gradually from 42.0 to 10.2, from 56.4 to 10.8, and from 0.74 to 0.61, respectively, with host …

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Bees Associated With Louisiana Longleaf Pine Savannas, Chanda Sara Bartholomew Jan 2004

Bees Associated With Louisiana Longleaf Pine Savannas, Chanda Sara Bartholomew

LSU Master's Theses

Longleaf pine savannas are perhaps the most threatened ecosystems in North America. Despite a well documented and highly diverse flora, little has been published on insects in general and, in particular, on bees that provide the valuable service of plant pollination. Thus, the aims of this study were to: 1) survey bees found in two savanna types in southeastern Louisiana; and 2) contrast the diversity and species composition of these two savanna types. An ancillary goal was to contrast two collecting protocols for bees in the savanna habitat. Overall, a total of 3,407 bees were collected representing 125 species. Of …

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Volatiles Associated With Formosan Subterranean Termites And Related Methods Development, Paul Mclaughlin Jan 2004

Volatiles Associated With Formosan Subterranean Termites And Related Methods Development, Paul Mclaughlin

LSU Master's Theses

An investigation was conducted to identify volatiles associated with active Formosan termites. Using a combined technique of short path thermal desorption-gas chromatography/mass spectrometry (SPTD-GC/MS), qualitative comparisons were made between compounds detected in treatments containing active Formosan termites versus those detected in controls without Formosan termites. Except for dimethyl disulfide, none of the compounds were consistently detected in the treatments but not the controls for the four termite groups tested. However, in each of the three groups that dimethyl disulfide was detected, dead termites that were decomposing along with active termites were present. Therefore, none of the compounds could be classified …

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Abiotic And Biotic Factors Affecting The Distribution Of Solenopsis Invicta Buren, Brachymyrmex Sp., And Linepithema Humile (Mayr) In East Baton Rouge Parish, Louisiana, Jessica Lynn Rosson Jan 2004

Abiotic And Biotic Factors Affecting The Distribution Of Solenopsis Invicta Buren, Brachymyrmex Sp., And Linepithema Humile (Mayr) In East Baton Rouge Parish, Louisiana, Jessica Lynn Rosson

LSU Master's Theses

Ant populations and their distribution are affected by many circumstances. Abiotic factors such as weather, water availability, and soil characteristics may determine if a habitat is suitable for ants. Other factors such as level of disturbance, available food resources, reproductive biology, and natural enemies also contribute to defining ant distribution. Three ant species in East Baton Rouge parish, Louisiana were studied to determine what factors affected their distribution by measuring abiotic and biotic factors at sampling sites throughout the parish. These factors included weather, water availability, vegetation types, level of disturbance, and soil characteristics. Factors which predict abundance of Solenopsis …

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Integration Of Management Tactics For The Rice Water Weevil Lissorhoptrus Oryzophilus Kuschel With Particular Emphasis On Use Of Plant Resistance (Tolerance), Li Zou Jan 2004

Integration Of Management Tactics For The Rice Water Weevil Lissorhoptrus Oryzophilus Kuschel With Particular Emphasis On Use Of Plant Resistance (Tolerance), Li Zou

LSU Doctoral Dissertations

Studies were conducted to test the hypothesis, significant benefits can be achieved for the management of rice water weevil, Lissorhoptrus oryzophilus Kuschel, by the use of rice varieties with low levels of host plant resistance coupled with the judicious use of cultural practices and insecticides. Tolerant traits of a current commercial variety of rice, "Bengal", was manifested consistently over multiple years. Study on rice growth as effected by weevil injury showed that pruning of root systems by larvae of weevil resulted in a decrease in tiller number and shoot biomass of rice plants in the vegetative stage of growth. Yield …

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Interactions Of Insect Herbivory And Multiple Abiotic Stress Agents On Two Wetland Tree Species In Southeast Louisiana Swamps, Rebecca Faye Souther-Effler Jan 2004

Interactions Of Insect Herbivory And Multiple Abiotic Stress Agents On Two Wetland Tree Species In Southeast Louisiana Swamps, Rebecca Faye Souther-Effler

LSU Doctoral Dissertations

Forested wetlands in Louisiana are hydrologically isolated from the Mississippi River, impounded by manmade structures, impacted by saltwater intrusion, and are sinking, resulting in more frequent flooding for longer periods. Additionally, defoliation of the two dominant trees, baldcypress (Taxodium distichum L. Rich) and water tupelo (Nyssa aquatica L.), occur frequently during spring. In Louisiana, the baldcypress leafroller, BCLR, (Archips goyerana Kruse) and the forest tent caterpillar, FTC, (Malacosoma disstria Hubner) defoliate up to 120,000ha of baldcypress-tupelo swamps. Restoration plans call for reintroducing Mississippi River water (diversions) to increase sediment elevation, promote natural regeneration, and enhance primary and secondary productivity. In …

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Biology And Host Finding Of Predaceous Hister Beetles (Coleoptera: Histeridae) Associated With Ips Spp. (Coleoptera: Scolytidae) In Loblolly Pine (Pinus Taeda L.), William Pinson Shepherd Jan 2004

Biology And Host Finding Of Predaceous Hister Beetles (Coleoptera: Histeridae) Associated With Ips Spp. (Coleoptera: Scolytidae) In Loblolly Pine (Pinus Taeda L.), William Pinson Shepherd

LSU Doctoral Dissertations

The most common predaceous Histeridae (Coleoptera) found associated with Ips engraver beetles (Coleoptera: Scolytidae) in Louisiana were Platysoma attenuata LeConte, Pla. cylindrica (Paykull), Pla. parallelum (Say), and Plegaderus transversus (Say). Seasonal abundance of histerids in flight traps coincided with Ips spp. activity in the area. Histerid adults arrived at loblolly pine (Pinus taeda L.) logs one wk after Ips attacks had begun. As a group, histerids exhibited a bimodal emergence pattern with the first peak occurring during Ips emergence and a second four wks later, indicating that they fed on bark beetles and associated organisms arriving later in the colonization …

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Evaluation Of Injury And Management Strategies For Stink Bugs (Heteroptera: Pentatomidae) On Cotton, Gossypium Hirsutum L., Melissa Marie Willrich Jan 2004

Evaluation Of Injury And Management Strategies For Stink Bugs (Heteroptera: Pentatomidae) On Cotton, Gossypium Hirsutum L., Melissa Marie Willrich

LSU Doctoral Dissertations

The effects of brown stink bug, Euschistus servus (Say), and southern green stink bug, Nezara viridula (L.), feeding on pre-flowering, flowering, and senescing cotton, Gossypium hirsutum L., plants were evaluated in field studies. Vegetative stage seedlings and flower buds (squares) were not significantly injured by adults or nymphs of either species in no-choice studies. Brown stink bug adults induced boll abscission, and reduced seedcotton yield and seed germination in bolls accumulating „T 350, „T 550, and 101 to „T 600 heat units beyond anthesis, respectively. In free-choice tests, boll preference was evaluated during each of the initial five weeks of …

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Seasonal Occurrence Of Phyllophaga Species And Biological Studies Of Phyllophage Ephilida (Say) On Sweet Potato, Ipomoea Batatas (L) Lam, In Louisiana, Aboubacar Diagne Jan 2004

Seasonal Occurrence Of Phyllophaga Species And Biological Studies Of Phyllophage Ephilida (Say) On Sweet Potato, Ipomoea Batatas (L) Lam, In Louisiana, Aboubacar Diagne

LSU Doctoral Dissertations

The biology of Phyllophaga ephilida (Say) was studied in Louisiana with both laboratory and field experiments from 1998 through 2003. The seasonal occurrence of common adult Phyllophaga species in sweet potato growing areas was surveyed with blacklight traps. P. ephilida and P. crinita (Burmeister) were the most common species at all locations. The attractiveness of seven methyl esters of L-isoleucine and L-valine blends to P. ephilida males was evaluated in sweet potato fields in 1999 and 2000. The 100% methyl ester of L-isoleucine was significantly more attractive than all other blend ratios that were tested. The life cycle of P. …

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Investigation Of Insect-Weed Interactions In The Rice Agroecosystem, Kelly V. Tindall Jan 2004

Investigation Of Insect-Weed Interactions In The Rice Agroecosystem, Kelly V. Tindall

LSU Doctoral Dissertations

Interactions between graminaceous weed and insect pests of rice and between management practices for these pests were investigated. Studies were conducted to examine preference and performance of rice water weevil, Lissorhoptrus oryzophilus Kuschel, on several weeds commonly found in rice fields. Several weeds were more preferred than rice, and larvae were present on several dicotyledonous weeds, suggesting the host range of L. oryzophilus is broader than previously thought. Effects of the presence of barnyardgrass, (Echinochloa crus-galli Beauv.), on rice stink bugs, Oebalus pugnax F., and L. oryzophilus populations in rice fields were investigated. Presence of barnyardgrass and the synchrony …

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