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Full-Text Articles in Life Sciences

Genome-Wide Analysis Of The Interaction Between The Endosymbiotic Bacterium Wolbachia And Its Drosophila Host, Zhiyong Xi, Laurent Gavotte, Yan Xie, Stephen L. Dobson Jan 2008

Genome-Wide Analysis Of The Interaction Between The Endosymbiotic Bacterium Wolbachia And Its Drosophila Host, Zhiyong Xi, Laurent Gavotte, Yan Xie, Stephen L. Dobson

Entomology Faculty Publications

BACKGROUND: Intracellular Wolbachia bacteria are obligate, maternally-inherited, endosymbionts found frequently in insects and other invertebrates. The success of Wolbachia can be attributed in part to an ability to alter host reproduction via mechanisms including cytoplasmic incompatibility (CI), parthenogenesis, feminization and male killing. Despite substantial scientific effort, the molecular mechanisms underlying the Wolbachia/host interaction are unknown.

RESULTS: Here, an in vitro Wolbachia infection was generated in the Drosophila S2 cell line, and transcription profiles of infected and uninfected cells were compared by microarray. Differentially-expressed patterns related to reproduction, immune response and heat stress response are observed, including multiple genes that have …


Trophic Interactions Between Two Herbivorous Insects, Galerucella Calmariensis And Myzus Lythri, Feeding On Purple Loosestrife, Lythrum Salicaria, And Two Insect Predators, Harmonia Axyridis And Chrysoperla Carnea, Bethzayda Matos, John J. Obrycki Jan 2007

Trophic Interactions Between Two Herbivorous Insects, Galerucella Calmariensis And Myzus Lythri, Feeding On Purple Loosestrife, Lythrum Salicaria, And Two Insect Predators, Harmonia Axyridis And Chrysoperla Carnea, Bethzayda Matos, John J. Obrycki

Entomology Faculty Publications

The effects of two herbivorous insects, Galerucella calmariensis Duftschmid and Myzus lythri L. (Coleoptera: Chrysomelidae), feeding on purple loosestrife, Lythrum salicaria L. (Myrtiflorae: Lythraceae), were measured in the presence of two insect predators, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) and Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). A greenhouse cage experiment examined the direct effects of these predators on these herbivores, and indirect effects of predation on aboveground biomass, defoliation, number of leaves, and internode length. Eight treatment combinations with G. calmariensis, M. lythri, H. axyridis and C. carnea were applied to caged L. salicaria. The experiment ended …


Prevalence And Association Of The Laboulbenialean Fungus Hesperomyces Virescens (Laboulbeniales: Laboulbeniaceae) On Coccinellid Hosts (Coleoptera: Coccinellidae) In Kentucky, Usa, James D. Harwood, Carlo Ricci, Roberto Romani, Kevin M. Pitz, Alex Weir, John J. Obrycki Oct 2006

Prevalence And Association Of The Laboulbenialean Fungus Hesperomyces Virescens (Laboulbeniales: Laboulbeniaceae) On Coccinellid Hosts (Coleoptera: Coccinellidae) In Kentucky, Usa, James D. Harwood, Carlo Ricci, Roberto Romani, Kevin M. Pitz, Alex Weir, John J. Obrycki

Entomology Faculty Publications

The laboulbenialean fungi occur throughout the world and are closely associated with a range of arthropods, including many coleopteran hosts. Throughout the summer of 2004, coccinellids were collected from a Bluegrass savanna woodland ecosystem, dominated by blue ash Fraxinus quadrangulata and Chinkapin Oak Quercus muehlenbergii, and the adults were examined for the presence of Hesperomyces virescens using binocular and scanning electron microscopy. Over 80% of adult Harmonia axyridis, a species previously reported as having a persistent association with the fungus, were infected. No significant differences were observed in incidence on male and female hosts, however, the distribution of …


Comparative Genetic Studies Of Native And Introduced Coccinellidae In North America, Elliot S. Krafsur, John J. Obrycki, James D. Harwood Aug 2005

Comparative Genetic Studies Of Native And Introduced Coccinellidae In North America, Elliot S. Krafsur, John J. Obrycki, James D. Harwood

Entomology Faculty Publications

During the past four decades, several species of aphidophagous Coccinellidae became established in North America, including Coccinella septempunctata, Harmonia axyridis, Hippodamia variegata, and Propylea quatuordecimpunctata. After their establishment, unknown circumstances favoured a rapid increase in population densities and distribution of H. axyridis and C. septempunctata at localities hundreds and thousands of kilometers from their release sites. Propylea quatuordecimpunctata and Hippodamia variegata have spread more slowly after becoming established in northeastern North America. Comparative studies based upon allozyme variation in these four introduced species and in six native North American species of ladybird beetles revealed …


Quantifying Aphid Predation Rates Of Generalist Predators In The Field, James D. Harwood, John J. Obrycki Aug 2005

Quantifying Aphid Predation Rates Of Generalist Predators In The Field, James D. Harwood, John J. Obrycki

Entomology Faculty Publications

The community of predators within agroecosystems has the potential to restrict aphid populations, especially early in the season before exponential increases in density and prior to the arrival of specialist natural enemies. Although direct observations of predation, laboratory feeding trials and manipulative field studies have been used to estimate levels of biological control exerted by different species (or potentially negative interactions between them), it is often difficult to extrapolate results to naturally occurring interactions in the field.

Over 100 investigations have utilized gut-content analysis to estimate aphid predation rates by predators. Throughout the last century, gut dissection, which enables the …


Quantitative Analysis Of Hemocyte Morphological Abnormalities Associated With Campoletis Sonorensis Parasitization, Matthew W. Turnbull, Stacy B. Martin, Bruce A. Webb Jan 2004

Quantitative Analysis Of Hemocyte Morphological Abnormalities Associated With Campoletis Sonorensis Parasitization, Matthew W. Turnbull, Stacy B. Martin, Bruce A. Webb

Entomology Faculty Publications

Endoparasitoids of arthropods evoke host cellular immune responses that result in hemocytic encapsulation of the endoparasitoid, unless these responses are disrupted by the parasite. Our interest has focused on mutualistic viruses found in some hymenopteran endoparasitoids that disrupt hemocyte function and prevent encapsulation. Specifically, the Campoletis sonorensis polydnavirus interacts with wasp factors to suppress immunity via expression of intracellular and secreted viral proteins. To study the roles of specific parasitization-associated factors on immunocyte morphology, fluorescence microscopy was used to visualize the actin cytoskeleton in infected and uninfected cells, or after treatment with C. sonorensis ovarian proteins or plasma from infected …


Viral And Insect Genes That Inhibit The Immune System And Methods Of Use Thereof, Bruce A. Webb, Liwang Cui Oct 1998

Viral And Insect Genes That Inhibit The Immune System And Methods Of Use Thereof, Bruce A. Webb, Liwang Cui

Entomology Faculty Patents

Viral, endoparasitoid and/or host genes that specifically inhibit the immune response of insect pests, useful for broadening the host range of insect viruses. Symbiont viruses of insect pests are genetically modified to express immune-suppressing proteins or biologically active fragments thereof and, optionally toxins, to increase the virus host range and/or improve the efficacy of insect pathogens.


Automated Adjustable Interval Insect Trap, Yongbiao Liu, Kenneth F. Haynes Jul 1994

Automated Adjustable Interval Insect Trap, Yongbiao Liu, Kenneth F. Haynes

Entomology Faculty Patents

An automated, adjustable-interval insect trap includes a plurality of individual cards having a surface coated with insect adhesive to capture insects. The cards are received on trays having wheels that engage a series of four parallel guide rails. By operation of a positioning mechanism, the trays carrying the cards are moved along the guide rails, one at a time, into an insect capturing position for a selected time interval. The positioning mechanism includes a timer, a drive motor, an axle operatively connected to the drive motor and a series of spaced fan plates mounted on the axle at longitudinally spaced …