Entomology Commons^™

Benthic Collector And Grazer Communities Are Threatened By Hemlock Woolly Adelgid-Induced Eastern Hemlock Loss, Joshua K. Adkins, Lynne K. Rieske

Entomology Faculty Publications

Eastern hemlock (Tsuga canadensis (L.) is a foundation species in eastern North America where it is under threat from the highly invasive, exotic hemlock woolly adelgid (Adelges tsugae). Eastern hemlock is especially important in riparian areas of Central and Southern Appalachia, so we compared the spatial and temporal composition of benthic collector-gatherers, collector-filterers, and grazers in headwater streams with hemlock-dominated riparian vegetation to those with deciduous tree-dominated riparian vegetation to evaluate the extent to which adelgid-induced hemlock loss could influence composition and abundance of these two functional feeding groups. We found differences in benthic invertebrate abundance and …

Temperature And Development Impacts On Housekeeping Gene Expression In Cowpea Aphid, Aphis Craccivora (Hemiptera: Aphidiae), Chunxiao Yang, Huipeng Pan, Yong Liu, Xuguo Zhou

Entomology Faculty Publications

Quantitative real-time PCR (qRT-PCR) is a powerful technique to quantify gene expression. To standardize gene expression studies and obtain more accurate qRT-PCR analysis, normalization relative to consistently expressed housekeeping genes (HKGs) is required. In this study, ten candidate HKGs including elongation factor 1 α (EF1A), ribosomal protein L11 (RPL11), ribosomal protein L14 (RPL14), ribosomal protein S8 (RPS8), ribosomal protein S23 (RPS23), NADH-ubiquinone oxidoreductase (NADH), vacuolar-type H+-ATPase (ATPase), heat shock protein 70 (HSP70), 18S ribosomal RNA (18S), and 12S ribosomal RNA (12S …

Colemanus Keeleyorum (Braconidae, Ichneutinae S. L.): A New Genus And Species Of Eocene Wasp From The Green River Formation Of Western North America, J. Ray Fisher, Erika Tucker, Michael Sharkey

Entomology Faculty Publications

A new genus and species of Ichneutinae s. l., Colemanus keeleyorum Fisher, is described from the Eocene Green River Formation in Colorado, USA. Colemanus was placed on a phylogenetic hypothesis using morphological data. Using a parsimony criterion, Colemanus is placed within Proteropini (Ichneutinae s. l.). Reconstructions of well-preserved regions (mesosomal dorsum and wings) are included. A previously described species from lower Oligocene Baltic amber is transferred to Colemanus, resulting in the new combination C. contortus (Brues, 1933).

Insecticide Resistance In The Bed Bug Comes With A Cost, Jennifer R. Gordon, Michael F. Potter, Kenneth F. Haynes

Entomology Faculty Publications

Adaptation to new environmental stress is often associated with an alteration of one or more life history parameters. Insecticide resistant populations of insects often have reduced fitness relative to susceptible populations in insecticide free environments. Our previous work showed that three populations of bed bugs, Cimex lectularius L., evolved significantly increased levels of resistance to one product containing both β-cyfluthrin and imidacloprid insecticides with only one generation of selection, which gave us an opportunity to explore potential tradeoffs between life history parameters and resistance using susceptible and resistant strains of the same populations. Life history tables were compiled by collecting …

Nutrition Regulation Of Male Accessory Gland Growth And Maturation In Tribolium Castaneum, Jingjing Xu, Ashlee L. Anciro, Subba R. Palli

Entomology Faculty Publications

Insulin/IGF-1 signaling (IIS) pathway is known to control growth, development and reproduction. Insulin-like peptide mediated body size plasticity in Drosophila melanogaster has been reported. Here, our studies showed that IIS pathway and nutrition regulate growth and maturation of the male accessory gland (MAG) in the red flour beetle, Tribolium castaneum. The size of MAG increased from day 1 to day 5 post-adult emergence (PAE). This increase in the size of MAG is contributed by an increase in cell size, but not cell number. The growth of MAG was impaired after double-stranded RNA (dsRNA)-mediated knockdown in the expression of genes …

Selection Of Reference Genes For Rt-Qpcr Analysis In The Monarch Butterfly, Danaus Plexippus (L.), A Migrating Bio-Indicator, Huipeng Pan, Xiaowei Yang, Keith Bidne, Richard L. Hellmich, Blair D. Siegfried, Xuguo Zhou

Entomology Faculty Publications

Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a powerful technique to quantify gene expression. To facilitate gene expression study and obtain accurate results, normalization relative to stably expressed reference genes is crucial. The monarch butterfly, Danaus plexippus (L.), is one of the most recognized insect species for its spectacular annual migration across North America. Besides its great voyages, D. plexippus has drawn attention to its role as a bio-indicator, ranging from genetically modified organisms (GMOs) to natural ecosystems. In this study, nine reference genes from D. plexippus genome were selected as the candidate reference genes. The expression profiles of these …

Bacterial Symbionts, Buchnera, And Starvation On Wing Dimorphism In English Grain Aphid, Sitobion Avenae (F.) (Homoptera: Aphididae), Fangmei Zhang, Xiangrui Li, Yunhui Zhang, Brad Coates, Xuguo Joe Zhou, Dengfa Cheng

Entomology Faculty Publications

Wing dimorphism in aphids can be affected by multiple cues, including both biotic (nutrition, crowding, interspecific interactions, the presence of natural enemies, maternal and transgenerational effects, and alarm pheromone) and abiotic factors (temperature, humidity, and photoperiod). The majority of the phloem-feeding aphids carry Buchnera, an obligate symbiotic proteobacteria. Buchnera has a highly reduced genome size, but encode key enzymes in the tryptophan biosynthetic pathway and is crucial for nutritional balance, development and reproduction in aphids. In this study, we investigated the impact of two nutritional-based biotic factors, symbionts and starvation, on the wing dimorphism in the English grain aphid, …

Flow Cytometry And K-Mer Analysis Estimates Of The Genome Sizes Of Bemisia Tabaci B And Q (Hemiptera: Aleyrodidae), Li T. Guo, Shao L. Wang, Qing J. Wu, Xuguo Zhou, Wen Xie, You J. Zhang

Entomology Faculty Publications

The genome sizes of the B- and Q-types of the whitefly Bemisia tabaci (Gennnadius) were estimated using flow cytometry (Drosophila melanogaster as the DNA reference standard and propidium iodide (PI) as the fluorochrome) and k-mer analysis. For flow cytometry, the mean nuclear DNA content was 0.686 pg for B-type males, 1.392 pg for B-type females, 0.680 pg for Q-type males, and 1.306 pg for Q-type females. Based on the relationship between DNA content and genome size (1 pg DNA = 980 Mbp), the haploid genome size of B. tabaci ranged from 640 to 682 Mbp. For k-mer analysis, genome …

The Relationship Between Manuscript Title Structure And Success: Editorial Decisions And Citation Performance For An Ecological Journal, Charles W. Fox, C. Sean Burns

Entomology Faculty Publications

A poorly chosen article title may make a paper difficult to discover or discourage readership when discovered, reducing an article's impact. Yet, it is unclear how the structure of a manuscript's title influences readership and impact. We used manuscript tracking data for all manuscripts submitted to the journal Functional Ecology from 2004 to 2013 and citation data for papers published in this journal from 1987 to 2011 to examine how title features changed and whether a manuscript's title structure was predictive of success during the manuscript review process and/or impact (citation) after publication. Titles of manuscripts submitted to Functional Ecology …

A Comprehensive Selection Of Reference Genes For Rt-Qpcr Analysis In A Predatory Lady Beetle, Hippodamia Convergens (Coleoptera: Coccinellidae), Huipeng Pan, Xiaowei Yang, Blair D. Siegfried, Xuguo Zhou

Entomology Faculty Publications

Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable, rapid, and reproducible technique for measuring and evaluating changes in gene expression. To facilitate gene expression studies and obtain more accurate RT-qPCR data, normalization relative to stable reference genes is required. In this study, expression profiles of seven candidate reference genes, including β-actin (Actin), elongation factor 1 α (EF1A), glyceralde hyde-3-phosphate dehydro-genase (GAPDH), cyclophilins A (CypA), vacuolar-type H+-ATPase (ATPase), 28S ribosomal RNA (28S), and 18S ribosomal RNA (18S) from Hippodamia convergens were investigated. H. …

Mapk Signaling Pathway Alters Expression Of Midgut Alp And Abcc Genes And Causes Resistance To Bacillus Thuringiensis Cry1ac Toxin In Diamondback Moth, Zhaojiang Guo, Shi Kang, Defeng Chen, Qingjun Wu, Shaoli Wang, Wen Xie, Xun Zhu, Simon W. Baxter, Xuguo Zhou, Juan Luis Jurat-Fuentes, Youjun Zhang

Entomology Faculty Publications

Insecticidal crystal toxins derived from the soil bacterium Bacillus thuringiensis (Bt) are widely used as biopesticide sprays or expressed in transgenic crops to control insect pests. However, large-scale use of Bt has led to field-evolved resistance in several lepidopteran pests. Resistance to Bt Cry1Ac toxin in the diamondback moth, Plutella xylostella (L.), was previously mapped to a multigenic resistance locus (BtR-1). Here, we assembled the 3.15 Mb BtR-1 locus and found high-level resistance to Cry1Ac and Bt biopesticide in four independent P. xylostella strains were all associated with differential expression of a midgut membrane-bound alkaline phosphatase (ALP …

Pyrosequencing Reveals A Shift In Symbiotic Bacteria Populations Across Life Stages Of Bactrocera Dorsalis, Awawing A. Andongma, Lun Wan, Yong-Cheng Dong, Ping Li, Nicolas Desneux, Jennifer A. White, Chang-Ying Niu

Entomology Faculty Publications

Bactrocera dorsalis is one of the most economically important fruit flies around the world. In this study, 454 pyrosequencing was used to identify the bacteria associated with different developmental stages of B. dorsalis. At ≥ 97% nucleotide similarity, total reads could be assigned to 172 Operational Taxonomic Units belonging to six phyla. Proteobacteria dominated in immature stages while Firmicutes dominated in adult stages. The most abundant families were Enterococcaceae and Comamondaceae. The genus Comamonas was most abundant in pupae whereas completely absent in adults. Some identified species had low sequence similarity to reported species indicating the possibility of …

Stably Expressed Housekeeping Genes Across Developmental Stages In The Two-Spotted Spider Mite, Tetranychus Urticae, Chunxiao Yang, Huipeng Pan, Yong Liu, Xuguo Zhou

Entomology Faculty Publications

Quantitative real-time PCR (qRT-PCR) is a reliable and reproducible technique for measuring mRNA expression. To facilitate gene expression studies and obtain more accurate qRT-PCR analysis, normalization relative to stable housekeeping genes is mandatory. In this study, ten housekeeping genes, including beta-actin (Actin), elongation factor 1 α (EF1A), glyceralde hyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein L13 (RPL13), ribosomal protein 49 (RP49), α-tubulin (Tubulin), vacuolar-type H+-ATPase (v-ATPase), succinate dehydrogenase subunit A (SDHA) , 28S ribosomal RNA (28S), and 18S ribosomal RNA (18S) from …

Methyl Farnesoate Plays A Dual Role In Regulating Drosophila Metamorphosis, Di Wen, Crisalejandra Rivera-Perez, Mohamed Abdou, Qiangqiang Jia, Qianyu He, Xi Liu, Ola Zyaan, Jingjing Xu, William G. Bendena, Stephen S. Tobe, Fernando G. Noriega, Subba R. Palli, Jian Wang, Sheng Li

Entomology Faculty Publications

Corpus allatum (CA) ablation results in juvenile hormone (JH) deficiency and pupal lethality in Drosophila. The fly CA produces and releases three sesquiterpenoid hormones: JH III bisepoxide (JHB3), JH III, and methyl farnesoate (MF). In the whole body extracts, MF is the most abundant sesquiterpenoid, followed by JHB3 and JH III. Knockout of JH acid methyl transferase (jhamt) did not result in lethality; it decreased biosynthesis of JHB3, but MF biosynthesis was not affected. RNAi-mediated reduction of 3-hydroxy-3-methylglutaryl CoA reductase (hmgcr) expression in the CA decreased biosynthesis and titers of the three sesquiterpenoids, resulting in …

Finding Our Way Through Phenotypes, Andrew R. Deans, Suzanna E. Lewis, Eva Huala, Salvatore S. Anzaldo, Michael Ashburner, James P. Balhoff, David C. Blackburn, Judith A. Blake, J. Gordon Burleigh, Bruno Chanet, Laurel D. Cooper, Mélanie Courtot, Sándor Csösz, Hong Cui, Wasila Dahdul, Sandip Das, T. Alexander Dececchi, Agnes Dettai, Rui Diogo, Robert E. Druzinsky, Michel Dumontier, Nico M. Franz, Frank Friedrich, George V. Gkoutos, Melissa Haendel, Luke J. Harmon, Terry F Hayamizu, Yongqun He, Heather M. Hines, Nizar Ibrahim, Laura M. Jackson, Pankaj Jaiswal, Christina James-Zorn, Sebastian Köhler, Guillaume Lecointre, Hilmar Lapp, Carolyn J. Lawrence, Nicolas Le Novère, John G. Lundberg, James Macklin, Austin R. Mast, Peter E. Midford, István Mikó, Christopher J. Mungall, Anika Oellrich, David Osumi-Sutherland, Helen Parkinson, Martín J. Ramírez, Stefan Richter, Peter N. Robinson, Alan Ruttenberg, Katja S. Schulz, Erik Segerdell, Katja C. Seltmann, Michael Sharkey, Aaron D. Smith, Barry Smith, Chelsea D. Specht, R. Burke Squires, Robert W. Thacker, Anne Thessen, Jose Fernandez-Triana, Mauno Vihinen, Peter D. Vize, Lars Vogt, Christine E. Wall, Ramona L. Walls, Monte Westerfeld, Robert A. Wharton, Christian S. Wirkner, James B. Woolley, Matthew J. Yoder, Aaron M. Zorn, Paula Mabee

Entomology Faculty Publications

Despite a large and multifaceted effort to understand the vast landscape of phenotypic data, their current form inhibits productive data analysis. The lack of a community-wide, consensus-based, human- and machine-interpretable language for describing phenotypes and their genomic and environmental contexts is perhaps the most pressing scientific bottleneck to integration across many key fields in biology, including genomics, systems biology, development, medicine, evolution, ecology, and systematics. Here we survey the current phenomics landscape, including data resources and handling, and the progress that has been made to accurately capture relevant data descriptions for phenotypes. We present an example of the kind of …

Spatial And Temporal Dynamics Of Predator-Prey Interactions In Winter Wheat, Katelyn A. Kowles

Theses and Dissertations--Entomology

Aphids (Hemiptera: Aphididae) are pests of multiple cropping systems, primarily due to the viruses they vector and direct crop damage that is exacerbated by their rapid population growth. In Kentucky, grain aphids (Rhopalosiphum padi and Sitobion avenae) cause significant yield loss to winter wheat as vectors of Barley Yellow Dwarf virus (BYDV), prompting the routine application of insecticides. Coupled with increasing human populations and decreasing arable land, it is increasingly evident that biological control services provided by natural enemies represent a viable long-term management option. Aphids are preyed upon by a diverse array of predators that can be …

A Revision Of The New World And Select Old World Species Of Cremnops Förster (Hymenoptera: Braconidae: Agathidinae), Erika M. Tucker

Theses and Dissertations--Entomology

Parasitoid wasps are an important group of organisms in need of systematic revision. This dissertation examines the cosmopolitan parasitoid wasp genus Cremnops. It is a compilation of three projects and significantly advances the taxonomic foundation of the genus.

The New World species of the genus Cremnops are revised. Thirty-three species of Cremnops are treated; five are described as new, i.e., C. bertae sp. nov., C. cluttsis sp. nov., C. nymphius sp. nov., C. wileycoyotius sp. nov. and C. witkopegasus sp. nov. Six species are synonymized, i.e., Cremnops caribensis Berta 1998, is synonymized under C. guanicanus Wolcott 1924; C. nigrosternum (Morrison …

A Comprehensive Understanding Of Corpse Management In Termites, Qian Sun

Theses and Dissertations--Entomology

Undertaking behavior is the disposal of dead individuals in social colonies to prevent potential pathogenic attack. This behavioral trait has convergently evolved in social insects (primarily termites, ants, and honeybee), and is considered an essential adaptation to social living. In honey bee and ants, workers recognize dead colony members through the postmortem change of chemical profile, and corpses are usually removed out of nest. However, in termites, little is known about the behavioral pattern, chemical cue or molecular basis. In the eastern subterranean termite, Reticulitermes flavipes, this study investigated undertaking behavior toward corpses of different origins and postmortem times. …

Invasiveness Of An Exotic Gall Wasp Is Influenced By Interactions With Exotic And Endemic Organisms, Ignazio Graziosi

Theses and Dissertations--Entomology

American chestnut was once a crucial component of North American forests, but it was functionally eliminated by the introduction of the chestnut blight fungus. Chestnut is recently experiencing resurgence, but the introduced Asian chestnut gall wasp, a specialist herbivore, threatens chestnut recovery. I characterized this invasion and the interactions developing with host associates as the gall wasp spread in North America. Gall wasp dispersal is attributable to host plant distribution, effects of prevailing winds during adult insect emergence, and to topography. This knowledge may be useful to more accurately predict locations of future gall wasp infestations. Gall wasp invasiveness is …

Evaluating A Novel Endophytic Grass For Its Potential To Reduce Invertebrate Populations And Associated Bird Strike Risk At Airports, Diana M. Miller

Theses and Dissertations--Entomology

Aircraft strikes are a significant safety hazard on airports worldwide. Wildlife management at airfields is the most effective tactic to reduce airstrike risk – to modify the habitat to be undesirable to animals. Tall fescue grasses containing a fungal symbiont may serve that purpose. They produce alkaloids that convey resistance to some grass-feeding invertebrates, which might in turn reduce incidence of insectivorous birds. A commercial endophytic grass (Avanex™) consisting of ‘Jackal’ tall fescue infected with a unique endophyte (AR 601) is purported to contain especially high levels of alkaloids and to reduce bird populations if planted at airports. I evaluated …

Mechanical Exclusion And Biological Control Strategies For The Invasive Brown Marmorated Stink Bug, Halyomorpha Halys (Hemiptera: Pentatomidae), Rachelyn Dobson

Theses and Dissertations--Entomology

The brown marmorated stink bug (Halyomorpha halys) is an invasive, agriculturally destructive pest present in most of the United States. Because organic farmers have few effective control options to combat this pest, three potential control options were investigated. Screens of different mesh sizes (0.42cm, 0.32cm, and 0.10cm) that covered vegetable crops were evaluated for their ability to exclude H. halys, allow the entry of beneficial insects, and protect the crop from various types of damage. H. halys and native stink bug egg masses were placed in an organic field and evidence of predation and parasitism from native …

Taxonomic And Molecular Studies In Cleridae And Hemiptera, John Moeller Leavengood Jr.

Theses and Dissertations--Entomology

Taxonomic changes are made based on checkered beetle (Coleoptera: Cleridae) types of the Natural History Museum, London (BMNH).Lectotypes are designated (and holotypes and paralectotypes recognized) for 44 species of Hydnocerinae, including the type species for Isolemidia, Parmius, Paupris, Allelidea, Blaesiopthalmus and Lemidia, four species of Enoclerus (Clerinae), and 14 species of Cymatodera (Tillinae). Annotations include comments on additional type material, new type locality, previous (type series) locality, and questionable or missing types. Phyllobaenus pallipes(Gorham) and P. rufithorax (Gorham) are synonymized with P. flavifemoratus(Gorham), P. chapini (Wolcott) is synonymized under P. lateralis (Gorham), and P. villosus (Schenkling) …

Developing A Sustainable Approach To Emerald Ash Borer Management, William C. Davidson

Theses and Dissertations--Entomology

Emerald ash borer, Agrilus planipennis Fairmaire, is an invasive wood boring beetle native to eastern Asia which was first detected in North America in 2002. All North American Fraxinus (ash) species are suitable hosts and susceptible to attack. Emerald ash borer larvae feed on phloem beneath the bark of infested trees resulting in girdling and mortality in as little as five years following initial infestation. Since its introduction near Detroit, Michigan, emerald ash borer has rapidly spread throughout much of the United States and portions of Canada, threatening the persistence of ash in invaded regions.

I tested a management strategy …

A Comparative Study Of Eastern And Western North American Populations Of Hippodamia Convergens (Coleoptera: Coccinellidae), Joshua S. Mccord

Theses and Dissertations--Entomology

Hippodamia convergens is a widely distributed insect predator in the United States and parts of Canada and Mexico. Several insectaries collect overwintering adults from aggregation sites in the Rocky Mountains during their winter dormancy. Collected beetles are then sold throughout the United States for augmentative biological control. This practice could have negative impacts on local populations of Hippodamia convergens in the Eastern United States. Intra-specific variation among H. convergens populations was examined for two characteristics of adults: photoperiodic induction of diapause and the presence of three known male-killing endosymbiont bacteria; Wolbachia, Spiroplasma, and Rickettsia. Four populations of H. …

New Insights Into The Function And Development Of The Soldier Caste In Termites, Li Tian

Theses and Dissertations--Entomology

The evolution of nonreproductive castes is a defining characteristic of eusociality. The function and developmental regulation of the altruistic worker and soldier caste is the central element contributing to major advantages of eusociality over solitary animals. The soldier caste is the first evolved sterile caste in termites. Their primary function is believed to be colony defense. However, the function and development of termite soldiers remains largely unknown. Because of their apparent morphological adaptation for fighting and their limited behavior repertoire, our understanding of colony defense by termite soldiers is limited to their physical defense. In addition, we know little about …

Transcriptome Analysis Of Host-Associated Differentiation In Bemisia Tabaci (Hemiptera: Aleyrodidae), Wen Xie, Qingjun Wu, Shaoli Wang, Xiaoguo Jiao, Litao Guo, Xuguo Zhou, Youjun Zhang

Entomology Faculty Publications

Host-associated differentiation is one of the driving forces behind the diversification of phytophagous insects. In this study, host induced transcriptomic differences were investigated in the sweetpotato whitefly Bemisia tabaci, an invasive agricultural pest worldwide. Comparative transcriptomic analyses using coding sequence (CDS), 5′ and 3′ untranslated regions (UTR) showed that sequence divergences between the original host plant, cabbage, and the derived hosts, including cotton, cucumber and tomato, were 0.11–0.14%, 0.19–0.26%, and 0.15–0.21%, respectively. In comparison to the derived hosts, 418 female and 303 male transcripts, respectively, were up-regulated in the original cabbage strain. Among them, 17 transcripts were consistently up-regulated …

Selection Of Reference Genes For Expression Analysis Using Quantitative Real-Time Pcr In The Pea Aphid, Acyrthosiphon Pisum (Harris) (Hemiptera, Aphidiae), Chunxiao Yang, Huipeng Pan, Yong Liu, Xuguo Zhou

Entomology Faculty Publications

To facilitate gene expression study and obtain accurate qRT-PCR analysis, normalization relative to stable expressed housekeeping genes is required. In this study, expression profiles of 11 candidate reference genes, including actin (Actin), elongation factor 1 α (EF1A), TATA-box-binding protein (TATA), ribosomal protein L12 (RPL12), β-tubulin (Tubulin), NADH dehydrogenase (NADH), vacuolar-type H+-ATPase (v-ATPase), succinate dehydrogenase B (SDHB), 28S ribosomal RNA (28S), 16S ribosomal RNA (16S), and 18S ribosomal RNA (18S) from the pea aphid Acyrthosiphon pisum, …

Novel Mutations And Mutation Combinations Of Ryanodine Receptor In A Chlorantraniliprole Resistant Population Of Plutella Xylostella (L.), Lei Guo, Pei Liang, Xuguo Zhou, Xiwu Gao

Entomology Faculty Publications

A previous study documented a glycine to glutamic acid mutation (G4946E) in ryanodine receptor (RyR) was highly correlated to diamide insecticide resistance in field populations of Plutella xylostella (Lepidoptera: Plutellidae). In this study, a field population collected in Yunnan province, China, exhibited a 2128-fold resistance to chlorantraniliprole. Sequence comparison between resistant and susceptible P. xylostella revealed three novel mutations including a glutamic acid to valine substitution (E1338D), a glutamine to leucine substitution (Q4594L) and an isoleucine to methionine substitution (I4790M) in highly conserved regions of RyR. Frequency analysis of all four mutations in this field population showed that the three …

Validation Of Reference Housekeeping Genes For Gene Expression Studies In Western Corn Rootworm (Diabrotica Virgifera Virgifera), Thaís Barros Rodrigues, Chitvan Khajuria, Haichuan Wang, Natalie Matz, Danielle Cunha Cardoso, Fernando Hercos Valicente, Xuguo Zhou, Blair Siegfried

Entomology Faculty Publications

Quantitative Real-time PCR (qRT-PCR) is a powerful technique to investigate comparative gene expression. In general, normalization of results using a highly stable housekeeping gene (HKG) as an internal control is recommended and necessary. However, there are several reports suggesting that regulation of some HKGs is affected by different conditions. The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a serious pest of corn in the United States and Europe. The expression profile of target genes related to insecticide exposure, resistance, and RNA interference has become an important experimental technique for study of western corn rootworms; however, lack …

Factors Limiting The Spread Of The Protective Symbiont Hamiltonella Defensa In Aphis Craccivora Aphids, Hannah R. Dykstra, Stephanie R. Weldon, Adam J. Martinez, Jennifer A. White, Keith R. Hopper, George E. Heimpel, Mark K. Asplen, Kerry M. Oliver

Entomology Faculty Publications

Many insects are associated with heritable symbionts that mediate ecological interactions, including host protection against natural enemies. The cowpea aphid, Aphis craccivora, is a polyphagous pest that harbors Hamiltonella defensa, which defends against parasitic wasps. Despite this protective benefit, this symbiont occurs only at intermediate frequencies in field populations. To identify factors constraining H. defensa invasion in Ap. craccivora, we estimated symbiont transmission rates, performed fitness assays, and measured infection dynamics in population cages to evaluate effects of infection. Similar to results with the pea aphid, Acyrthosiphon pisum, we found no consistent costs to infection using …