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Full-Text Articles in Life Sciences

Distinct Fitness Costs Associated With The Knockdown Of Rnai Pathway Genes In Western Corn Rootworm Adults, Ke Wu, Carolina Camargo, Elane Fishilevich, Kenneth E. Narva, Xiuping Chen, Caitlin E. Taylor, Blair D. Siegfried Jan 2017

Distinct Fitness Costs Associated With The Knockdown Of Rnai Pathway Genes In Western Corn Rootworm Adults, Ke Wu, Carolina Camargo, Elane Fishilevich, Kenneth E. Narva, Xiuping Chen, Caitlin E. Taylor, Blair D. Siegfried

Department of Entomology: Faculty Publications

RNA interference (RNAi) based approaches can potentially be used to control insect pests. These approaches may depend on the usage of microRNA (miRNA) or double stranded RNA (dsRNA) mediated gene knockdown, which likely involves proteins that regulate these pathways, such as Argonaute 1 (Ago1), Argonaute 2 (Ago2), Dicer 1 (Dcr1), Dicer 2 (Dcr2), and Drosha in insects. We previously performed functional characterization of Ago2 and Dcr2 of western corn rootworm (WCR), Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) and observed that knockdown of Ago2 and Dcr2 ameliorated the lethal effect induced by the dsRNA-mediated knockdown of an essential gene in WCR, thereby …


“Hummingbird” Floral Traits Interact Synergistically To Discourage Visitation By Bumble Bee Foragers, Robert J. Gegear, Rebecca Burns, Katharine A. Swoboda-Bhattarai Jan 2017

“Hummingbird” Floral Traits Interact Synergistically To Discourage Visitation By Bumble Bee Foragers, Robert J. Gegear, Rebecca Burns, Katharine A. Swoboda-Bhattarai

Department of Entomology: Faculty Publications

Pollination syndromes are suites of floral traits presumed to reflect adaptations to attract and utilize a “primary” type of animal pollinator. However, syndrome traits may also function to deter “secondary” flower visitors that reduce plant fitness through their foraging activities. Here we use the hummingbird-pollinated plant species Mimulus cardinalis as a model to investigate the potential deterrent effects of classic bird syndrome traits on bumble bee foragers. To establish that M. cardinalis flowers elicit an avoidance response in bees, we assessed the choice behavior of individual foragers on a mixed experimental array of M. cardinalis and its bee-pollinated sister species …


Reproductive Status Of Drosophila Suzukii (Diptera: Drosophilidae) Females Influences Attraction To Fermentation-Based Baits And Ripe Fruits, Katharine A. Swoboda-Bhattarai, Douglas R. Mcphie, Hannah Burrack Jan 2017

Reproductive Status Of Drosophila Suzukii (Diptera: Drosophilidae) Females Influences Attraction To Fermentation-Based Baits And Ripe Fruits, Katharine A. Swoboda-Bhattarai, Douglas R. Mcphie, Hannah Burrack

Department of Entomology: Faculty Publications

Drosophila suzukii (Matsumura) is an invasive species that is a devastating pest of soft-skinned fruit crops. Although much effort has been directed toward developing traps and attractants to monitor for D. suzukii, current monitoring tools do not reliably predict fruit infestation. The objective of this study was to determine if D. suzukii females at different developmental stages are differentially attracted to monitoring traps with fermentation-based baits and ripe fruits. Females were collected on the surface of traps, within traps, and on ripe fruits during three experiments at field locations in North Carolina, USA, and were dissected to determine their reproductive …


Dr. Kenneth P. Pruess Obituary, Robert J. Wright, Marion D. Ellis Jan 2017

Dr. Kenneth P. Pruess Obituary, Robert J. Wright, Marion D. Ellis

Department of Entomology: Faculty Publications

Dr. Kenneth P. Pruess, age 84, of Lincoln, Nebraska, died 11 December 2016. Kenneth was Professor of Entomology Emeritus at the University of Nebraska-Lincoln. He was born 21 June 1932 in Troy, Indiana, to Elmer and Clara (Grass) Pruess. Kenneth graduated from Purdue University in 1954 and earned his M.S. in Entomology in 1955 and Ph.D. in 1957, both from The Ohio State University. His dissertation was titled “Studies on the Clover Root Borer, Hylastinus obscurus (Marsham).” He married Neva Currie on 15 June 1963. He worked at the University of Nebraska’s North Platte Experiment Station from 1957–1965, Entomology Department …


Population Growth Rate Of Dry Bulb Mite, Aceria Tulipae (Acariformes: Eriophyidae), On Agriculturally Important Plants And Implications For Its Taxonomic Status, Agnieszka Kiedrowicz, Brian G. Rector, Suzanne Lommen, Lechosław Kuczyński, Wiktoria Szydło, Anna Skoracka Jan 2017

Population Growth Rate Of Dry Bulb Mite, Aceria Tulipae (Acariformes: Eriophyidae), On Agriculturally Important Plants And Implications For Its Taxonomic Status, Agnieszka Kiedrowicz, Brian G. Rector, Suzanne Lommen, Lechosław Kuczyński, Wiktoria Szydło, Anna Skoracka

Department of Entomology: Faculty Publications

Dry bulb mite (DBM), Aceria tulipae, is an economically important mite with a worldwide distribution and a broad host range. As a generalist, it is the most important eriophyoid mite attacking bulbous plants such as garlic, onion and tulip. To date, DBM has been recorded on host plants belonging to the families Liliaceae, Amaryllidaceae, Melanthiaceae and Asparagaceae. However, a precise understanding of DBM host range is lacking as it is largely based on casual records of mites on plants, some of which may include accidental hosts. Moreover, the possible existence of cryptic species has not been considered. In this …


Insect And Plant-Derived Mirnas In Greenbug (Schizaphis Graminum) And Yellow Sugarcane Aphid (Sipha Flava) Revealed By Deep Sequencing, Haichuan Wang, Chi Zhang, Yongchao Dou, Bin Yu, Yunfeng Liu, Tiffany Heng-Moss, Guoqing Lu, Michael Wachholtz, Jeffery D. Bradshaw, Paul Twigg, Erin Scully, Nathan Palmer, Gautam Sarath Jan 2017

Insect And Plant-Derived Mirnas In Greenbug (Schizaphis Graminum) And Yellow Sugarcane Aphid (Sipha Flava) Revealed By Deep Sequencing, Haichuan Wang, Chi Zhang, Yongchao Dou, Bin Yu, Yunfeng Liu, Tiffany Heng-Moss, Guoqing Lu, Michael Wachholtz, Jeffery D. Bradshaw, Paul Twigg, Erin Scully, Nathan Palmer, Gautam Sarath

Department of Entomology: Faculty Publications

Schizaphis graminum (green bug; GB) and Sipha flava (yellowsugarcane aphid; YSA) are two cereal aphid species with broad host ranges capable of establishing on sorghum (Sorghum bicolor) and several switchgrass (Panicum virgatum) cultivars. Switchgrass and sorghum are staple renewable bioenergy crops that are vulnerable to damage by aphids, therefore, identifying novel targets to control aphids has the potential to drastically improve yields and reduce losses in these bioenergy crops. Despite thewealth of genomic and transcriptomic information available from a closely related model aphid species, the pea aphid (Acyrthosiphon pisum), similar genomic information, including the …


A Comparison Of Honey Bee-Collected Pollen From Working Agricultural Lands Using Light Microscopy And Its Metabarcoding, M. D. Smart, R. S. Cornman, D. D. Iwanowicz, M. Mcdermott-Kubeczko, J. S. Pettis, M. S. Spivak, C. R.V. Otto Jan 2017

A Comparison Of Honey Bee-Collected Pollen From Working Agricultural Lands Using Light Microscopy And Its Metabarcoding, M. D. Smart, R. S. Cornman, D. D. Iwanowicz, M. Mcdermott-Kubeczko, J. S. Pettis, M. S. Spivak, C. R.V. Otto

Department of Entomology: Faculty Publications

Taxonomic identification of pollen has historically been accomplished via light microscopy but requires specialized knowledge and reference collections, particularly when identification to lower taxonomic levels is necessary. Recently, next-generation sequencing technology has been used as a cost-effective alternative for identifying beecollected pollen; however, this novel approach has not been tested on a spatially or temporally robust number of pollen samples. Here, we compare pollen identification results derived from light microscopy and DNA sequencing techniques with samples collected from honey bee colonies embedded within a gradient of intensive agricultural landscapes in the Northern Great Plains throughout the 2010–2011 growing seasons. We …


Parameters For Successful Parental Rnai As An Insect Pest Management Tool In Western Corn Rootworm, Diabrotica Virgifera Virgifera, Ana Maria Vélez, Elane Fishilevich, Natalie Matz, Nicholas P. Storer, Kenneth E. Narva, Blair D. Siegfried Jan 2017

Parameters For Successful Parental Rnai As An Insect Pest Management Tool In Western Corn Rootworm, Diabrotica Virgifera Virgifera, Ana Maria Vélez, Elane Fishilevich, Natalie Matz, Nicholas P. Storer, Kenneth E. Narva, Blair D. Siegfried

Department of Entomology: Faculty Publications

Parental RNAi (pRNAi) is an RNA interference response where the gene knockdown phenotype is observed in the progeny of the treated organism. pRNAi has been demonstrated in female western corn rootworms (WCR) via diet applications and has been described as a potential approach for rootworm pest management. However, it is not clear if plant-expressed pRNAi can provide effective control of next generation WCR larvae in the field. In this study, we evaluated parameters required to generate a successful pRNAi response in WCR for the genes brahma and hunchback. The parameters tested included a concentration response, duration of the dsRNA …


Fitness Costs Associated With Cry1f Resistance In The European Corn Borer, J. L. Petzold-Maxwell, Blair D. Siegfried, R. L. Hellmich, C. A. Abel, B. S. Coates, Terrence A. Spencer, R. J. Horikoshi, Aaron J. Gassmann Jan 2017

Fitness Costs Associated With Cry1f Resistance In The European Corn Borer, J. L. Petzold-Maxwell, Blair D. Siegfried, R. L. Hellmich, C. A. Abel, B. S. Coates, Terrence A. Spencer, R. J. Horikoshi, Aaron J. Gassmann

Department of Entomology: Faculty Publications

Crops producing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) are widely planted to manage insect pests. Bt crops can provide an effective tool for pest management; however, the evolution of Bt resistance can diminish this benefit. The European corn borer, Ostrinia nubilalis H€ubner, is a significant pest of maize and is widely managed with Bt maize in the Midwest of the United States. When Bt crops are grown in conjunction with non-Bt refuges, fitness costs of Bt resistance can delay the evolution of resistance. Importantly, fitness costs often vary with ecological factors, including host-plant genotype and diapause. In …


Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2015, Débora G. Montezano, Kayla A. Mollet, Grace E. Hirzel, Julie A. Peterson Jan 2017

Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2015, Débora G. Montezano, Kayla A. Mollet, Grace E. Hirzel, Julie A. Peterson

Department of Entomology: Faculty Publications

The western bean cutworm (WBC) is an important pest of corn and dry beans. This study was conducted within the historic range of WBC in western Nebraska; however, it has undergone a rapid range expansion into the eastern Corn Belt within the last 16 years. This field trial was established to evaluate the efficacy of a single application of foliar insecticides against this pest to prevent feeding damage to non-Bt corn ears. The trial was located at the University of Nebraska-Lincoln’s West Central Water Resources Field Laboratory in Keith County, Nebraska, USA (41.160246° N, –102.035695° W). A RCB design with …


Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2016, Débora G. Montezano, Kayla A. Mollet, Grace E. Hirzel, Julie A. Peterson Jan 2017

Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2016, Débora G. Montezano, Kayla A. Mollet, Grace E. Hirzel, Julie A. Peterson

Department of Entomology: Faculty Publications

The western bean cutworm (WBC) is an important pest of corn and dry beans. In addition to yield loss due to direct feeding on developing kernels in the ear, WBC infestation can also lead to secondary fungal infections. This study was conducted within the historic range of WBC in western Nebraska; however, it has undergone a rapid range expansion into the eastern Corn Belt within the last 16 years. This field trial was established to evaluate the efficacy of a single application of foliar insecticides against this pest to prevent feeding damage to non-Bt corn ears. The trial was located …


Thiamethoxam Toxicity And Effects On Consumption Behavior In Orius Insidiosus (Hemiptera: Anthocoridae) On Soybean, Carolina Camargo, Thomas Hunt, Loren J. Giesler, Blair D. Siegfried Jan 2017

Thiamethoxam Toxicity And Effects On Consumption Behavior In Orius Insidiosus (Hemiptera: Anthocoridae) On Soybean, Carolina Camargo, Thomas Hunt, Loren J. Giesler, Blair D. Siegfried

Department of Entomology: Faculty Publications

Neonicotinoid residues can be present in soybean vegetative tissue, prey insects, and flower tissues, possibly making them toxic to pollinators and natural enemies. Baseline information on the toxicity of neonicotinoids to beneficial insects other than pollinators through multiple routes of insecticide exposure is limited. The objectives of this study were 1) to evaluate the toxicity of thiamethoxam to the hemipteran predator, Orius insidiosus Say, exposed to residues through treated vegetative tissue and insect prey, and 2) to evaluate the effect of thiamethoxam on the abundance of this predator species in soybean fields. Predators were exposed to thiamethoxam in soybean leaves …


Amitraz And Its Metabolite Modulate Honey Bee Cardiac Function And Tolerance To Viral Infection, Scott T. O'Neal, Carlyle C. Brewster, Jeffrey R. Bloomquist, Troy D. Anderson Jan 2017

Amitraz And Its Metabolite Modulate Honey Bee Cardiac Function And Tolerance To Viral Infection, Scott T. O'Neal, Carlyle C. Brewster, Jeffrey R. Bloomquist, Troy D. Anderson

Department of Entomology: Faculty Publications

The health and survival of managed honey bee (Apis mellifera) colonies are affected by multiple factors, one of the most important being the interaction between viral pathogens and infestations of the ectoparasitic mite Varroa destructor. Currently, the only effective strategy available for mitigating the impact of viral infections is the chemical control of mite populations. Unfortunately, the use of in-hive acaricides comes at a price, as they can produce sublethal effects that are difficult to quantify, but may ultimately be as damaging as the mites they are used to treat. The goal of this study was to …


Atp-Sensitive Inwardly Rectifying Potassium Channel Modulators Alter Cardiac Function In Honey Bees, Scott T. O'Neal, Daniel R. Swale, Jeffrey R. Bloomquist, Troy D. Anderson Jan 2017

Atp-Sensitive Inwardly Rectifying Potassium Channel Modulators Alter Cardiac Function In Honey Bees, Scott T. O'Neal, Daniel R. Swale, Jeffrey R. Bloomquist, Troy D. Anderson

Department of Entomology: Faculty Publications

ATP-sensitive inwardly rectifying potassium (KATP) channels couple cellular metabolism to the membrane potential of the cell and play an important role in a variety of tissue types, including the insect dorsal vessel, making them a subject of interest not only for understanding invertebrate physiology, but also as a potential target for novel insecticides. Most of what is known about these ion channels is the result of work performed in mammalian systems, with insect studies being limited to only a few species and physiological systems. The goal of this study was to investigate the role that KATP channels play in …


Acute-Contact And Chronic-Systemic In Vivo Bioassays: Regional Monitoring Of Susceptibility To Thiamethoxam In Soybean Aphid (Hemiptera: Aphididae) Populations From The North Central United States, Matheus G.P.M. Ribeiro, Thomas E. Hunt, Blair Siegfried Jan 2017

Acute-Contact And Chronic-Systemic In Vivo Bioassays: Regional Monitoring Of Susceptibility To Thiamethoxam In Soybean Aphid (Hemiptera: Aphididae) Populations From The North Central United States, Matheus G.P.M. Ribeiro, Thomas E. Hunt, Blair Siegfried

Department of Entomology: Faculty Publications

The risks associated with soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in the North Central soybean systems has fostered the adoption of prophylactic chemical control practices, such as planting seeds treated with neonicotinoid insecticides, especially thiamethoxam. Consequently, there is a concern that increased selection pressure imposed on the arthropod–pest complex by this insecticide may lead to resistance. Therefore, in vivo bioassays were conducted to determine the susceptibility of soybean aphid to thiamethoxam among North Central U.S. populations. Concentration-mortality data were collected using contact glass-vial and detached-leaf systemic bioassays. The results of these experiments indicate that both bioassays were reliable to …