Life Sciences Commons^™

Managing Threats To The Urban Forest: From Dutch Elm Disease To Emerald Ash Borer - Learning From Experience, Christopher J. Borman

Doctor of Plant Health Program: Dissertations and Student Research

The urban forest provides important essential services to all municipalities; however, its value is often overlooked. The urban forest contributes to energy savings, environmental benefits, psychological well-being, and social benefits. Managing the urban forest in a sustainable manner is important if we wish to benefit from these services well into the future. Reliable management techniques have been created through previous experiences with pests, and these should be utilized and improved for use on urban forests.

American elm (Ulmus americana L.) was once a major component of the urban forests of North America. In 1927, Dutch elm disease (DED) was …

The Effect Of Agricultural Practices On Sugar Beet Root Aphid (Pemphigus Betae Doane) And Beneficial Epigeal Arthropods, Rudolph J. Pretorius

Department of Entomology: Dissertations, Theses, and Student Research

This study investigated the effect of several agricultural practices on the sugar beet root aphid (Pemphigus betae Doane) and beneficial epigeal natural enemies in western Nebraska sugar beet agroecosystems. Eight glyphosate-tolerant sugar beet varieties were evaluated under field conditions for their resistance to root aphids. High levels of aphid resistance were detected for some varieties. In conjunction to this, pitfall sampling was conducted to determine the beneficial epigeal natural enemy complex in the area, which could contribute to the management of both root aphids and glyphosate-resistant weeds. Ground beetles comprised an important and abundant component of this fauna, with …

Hexapod Herald - Vol. 26, No. 6, December 2014

Hexapod Herald and Other Entomology Department Newsletters

Contents: Welcome - Congratulations - Grants - Publications - Meeting an Off-Campus Students - Faculty News - Blasts from the Past - Calendar of Events

Eight Legged Encounters, Eileen A. Hebets

Eileen Hebets Publications

This program was funded in part by a National Science Foundation grant (DRL–1241482 to EAH). Material was developed in collaboration with Marie- Claire Chelini, Jessie Rose Storz, Cody Storz, and Malcolm Rosenthal. Steven Schwartz, Jason Stafstrom, Kathy French, Priscilla Grew, and Judy Diamond were all extremely helpful in grant writing, facilitating the first live event, and/or discussions. Pawl Tisdale (artist) was phenomenal to work with on all aspects of the project!

TABLE OF CONTENTS

CLASSIFICATION & TAXONOMY STATIONS
I. WHAT IS AN ARTHROPOD? page 4 a. The goal of this station is to introduce the audience to some basic information …

Multimodal Sensory Reliance In The Nocturnal Homing Of The Amblypygid Phrynus Pseudoparvulus (Class Arachnida, Order Amblypygi)?, Eileen A. Hebets, Alfonso Aceves-Aparicio, Samuel Aguilar-Argüello, Verner P. Bingman, Ignacio Escalante, Eben J. Gering, David R. Nelson, Jennifer Rivera, José Ángel Sánchez-Ruiz, Laura Segura-Hernández, Virginia Settepani, Daniel D. Wiegmann, Jay A. Stafstrom

Eileen Hebets Publications

Like many other nocturnal arthropods, the amblypygid Phrynus pseudoparvulus is capable of homing. The environment through which these predators navigate is a dense and heterogeneous tropical forest understory and the mechanism(s) underlying their putatively complex navigational abilities are presently unknown. This study explores the sensory inputs that might facilitate nocturnal navigation in the amblypygid P. pseudoparvulus. Specifically, we use sensory system manipulations in conjunction with field displacements to examine the potential involvement of multimodal—olfactory and visual—stimuli in P. pseudoparvulus’ homing behavior. In a first experiment, we deprived individuals of their olfactory capacity and displaced them to the opposite side of …

Dangerous Mating Systems: Signal Complexity, Signal Content And Neural Capacity In Spiders, Marie E. Herberstein, Anne E. Wignall, Eileen Hebets, Jutta M. Schneider

Eileen Hebets Publications

Spiders are highly efficient predators in possession of exquisite sensory capacities for ambushing prey, combined with machinery for launching rapid and determined attacks. As a consequence, any sexually motivated approach carries a risk of ending up as prey rather than as a mate. Sexual selection has shaped courtship to effectively communicate the presence, identity, motivation and/or quality of potential mates, which help ameliorate these risks. Spiders communicate this information via several sensory channels, including mechanical (e.g. vibrational), visual and/or chemical, with examples of multimodal signaling beginning to emerge in the literature. The diverse environments that spiders inhabit have further shaped …

Hexapod Herald - Vol. 26, No. 5, October 2014

Hexapod Herald and Other Entomology Department Newsletters

Content: Welcome - Publications - Faculty News - Meeting an Off-Campus Student - Grants and Other Funding - Bruner Club News - Student News - Travel - BUGFEST Success

De Novo Transcriptome Of The Hemimetabolous German Cockroach (Blattella Germanica), Xiaojie Zhou, Kun Qian, Ying Tong, Junwei Jerry Zhu, Xinghui Qiu, Xiaopeng Zeng

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: The German cockroach, Blattella germanica, is an important insect pest that transmits various pathogens mechanically and causes severe allergic diseases. This insect has long served as a model system for studies of insect biology, physiology and ecology. However, the lack of genome or transcriptome information heavily hinder our further understanding about the German cockroach in every aspect at a molecular level and on a genome-wide scale. To explore the transcriptome and identify unique sequences of interest, we subjected the B. germanica transcriptome to massively parallel pyrosequencing and generated the first reference transcriptome for B. germanica.

Methodology/Principal Findings: A …

Characterization Of Greenbug Feeding Behavior And Aphid (Hemiptera: Aphididae) Host Preference In Relation To Resistant And Susceptible Tetraploid Switchgrass Populations, Kyle G. Koch, Nathan Palmer, Mitch Stamm, Jeff D. Bradshaw, Erin Blankenship, Lisa M. Baird, Gautam Sarath, Tiffany M. Heng-Moss

Department of Entomology: Faculty Publications

Two choice studies were performed to evaluate greenbug, Schizaphis graminum (Rondani), and yellow sugarcane aphid, Sipha flava (Forbes), preference for two tetraploid switchgrass populations, Summer and Kanlow, and one experimental hybrid, K×S, derived by crossing Kanlow (male)×Summer (female) plants. Additionally, an assessment of S. graminum feeding behavior was performed on the same switchgrass populations, by using the electrical penetration graph (EPG) technique. Choice studies for S. flava indicated a lack of antixenosis, with no preference by aphids among any of the switchgrass populations at any time point. However, choice studies with S. graminum indicated a preference for the K×S plants …

Rna Interference As A Tool For The Functional Analysis Of Genes In The Colorado Potato Beetle, Leptinotarsa Decemlineata (Say), Ashley Danielle Yates

Department of Entomology: Dissertations, Theses, and Student Research

RNA interference (RNAi) is a naturally occurring phenomenon in eukaryotes in which a double-stranded RNA (dsRNA) suppresses the expression of a target gene. RNAi has markedly changed the way in which functional genetics studies are performed, especially in non-model organisms. In insects, the efficacy of RNAi is influenced by several factors, including the species and the methods of dsRNAs delivery.

The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is a pest of the plant family Solanaceae. RNAi in the CPB is of interest for potential use in insect management and as a tool to study the interaction with host plants. …

Hexapod Herald - Vol. 26, No. 4, August 2014

Hexapod Herald and Other Entomology Department Newsletters

Contents: Welcome - Congratulations - Faculty News - Publications - Grants - Travel - Meet an Off-Campus Student - Student News

An Evaluation Of Watermelon (Citrullus Spp.) Germplasm For Additional Sources Of Resistance To The Twospotted Spider Mite (Tetranychus Urticae Koch)., Hector Cantu Jr.

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Fourteen U.S plant introduction (PI) accessions of C. lanatus var. lanatus (4), C. lanatus var. citroides (5) C. colocynthis (5) and a known susceptible commercial cultivar ‘Sugar Baby’ were evaluated for resistance to the twospotted spider mite, Tetranychus urticae Koch, in a limited free-choice and free-choice bioassay under laboratory conditions. The limited free choice bioassay, involved nine Petri dish cages that held five randomly assigned leaves individually inoculated with two adult females and one adult male. Eggs, larva, and adults were counted over a nine day period. The free choice bioassay involved the even distribution of three mite infested …

Cercyonis Pegala Agawamensis (Satyridae): A New Butterfly Subspecies From The Coastal Salt Marshes Of The Northeastern United States Of America, Matthew D. Arey, Alex Grkovich

The Taxonomic Report of the International Lepidoptera Survey

A new subspecies of the Common Wood Nymph (Cercyonis pegala) from the New England coastline in the northeastern region of the United States is described on the basis of phenotype, behavior, habitat, seasonality, flight period, and phenology. Agawamensis is univoltine as in all pegala. The newly described subspecies occurs almost entirely in coastal salt marshes and estuarine meadows, quite atypical as understood for Cercyonis pegala. The newly described subspecies agawamensis predominately prefers and occurs within large open salt marshes but can also be found in similar habitat along smaller tidal rivers, coastal inlets and streams

A Case Of Sympatric Celastrina Ladon (Cramer), Celastrina Lucia (W. Kirby) And Celastrina Neglecta (Edwards) (Lycaenidae: Polyommatinae) In Northern Virginia, With Additional Records Of C. Lucia In Virginia, Harry Pavulaan

The Taxonomic Report of the International Lepidoptera Survey

A case of fully sympatric Celastrina ladon, C. lucia, and early spring brood C. neglecta is documented at a site in northern Virginia. Observations indicate that all three species occupy the same habitat, fly during the same flight period and utilize the same hostplant with no evidence of hybridization. C. ladon and C. lucia are obligate univoltines while C. neglecta is multivoltine. A later flight (second brood) of Celastrina neglecta at the same site utilizes eriophyid mite-induced leaf galls on the very same host tree species. Additional Virginia records of C. lucia are documented.

Larval Host Plants Of Enodia Anthedon, Satyrodes Appalachia And S. Eurydice In Vermont, Usa, David J. Hoag

The Taxonomic Report of the International Lepidoptera Survey

Field observation and captive rearing was used to clarify larval host plant use in Enodia anthedon, Satyrodes appalachia, and S. eurydice in Vermont, USA. In nature S. appalachia larvae were found on Carex lacustris, C. lupulina, C. gracillima, and C. tuckermanii. Enodia anthedon in nature was found to oviposit on grass and on Carex lacustris. Larvae of E. anthedon were found on C. lacustris and C. lupulina. In captivity, all but two E. anthedon larvae chose Carex over grass. Both E. appalachia and E. anthedon …

Obligate Male Death And Sexual Cannibalism In Dark Fishing Spiders, Steven Schwartz, William E. Wagner, Eileen A. Hebets

Eileen Hebets Publications

Male dark fishing spiders (Dolomedes tenebrosus Araneae, Pisauridae) always die during their first and only copulation, making all males monogynous. Such obligate male death can be adaptive if it facilitates sexual cannibalism, and if sexual cannibalism results in male reproductive benefits, such as an advantage in sperm competition through reduced female remating. We first conducted an experiment to determine the extent to which D. tenebrosus (1) males are cannibalized by females and (2) females engage in remating, both of which are prerequisites for several adaptive hypotheses of male self-sacrifice. We then conducted an experiment to test the hypothesis that …

Hexapod Herald - Vol. 26, No. 3, June 2014

Hexapod Herald and Other Entomology Department Newsletters

Content: Welcome - Congratulations - Faculty News - Grants - Publications - Meet an Off-Campus Student - Student News

Investigations Into Sensory Ecology And Gene Evolution Of The Pea Aphid (Acyrthosiphon Pisum), Swapna R. Purandare

School of Biological Sciences: Dissertations, Theses, and Student Research

Organisms use environmental cues to gather information required to perform activities that are essential for their survival and reproduction, such as searching for food, avoiding danger, and finding mates. They respond to the acquired information by changing their behavior or physiology, which may result in increased fitness. Due to the fundamental importance of information in an organism’s life, it is important to understand its acquisition, processing, and the organism’s response to it. In the work presented here, we used the pea aphid (Acyrthosiphon pisum), an insect that produces multiple phenotypes, or morphs, that are genetically identical, but differ …

Diversity And Ecology Of Host-Seeking Mosquitoes In Irrigated Agro-Ecosystems Of Clay County, Nebraska, Alister K. Bryson

Department of Entomology: Dissertations, Theses, and Student Research

In the United States, Nebraska has the third highest incidence of human West Nile virus (WNV). Since WNV was first detected in the state in 2002, 3,422 confirmed cases and 57 deaths have been reported. Irrigated agro-ecosystems, which have been associated with elevated WNV incidences in other states, are prevalent in Nebraska. The objectives of this investigation were to 1) characterize mosquito abundance and diversity in irrigated agro-ecosystems, and 2) evaluate associations of two primary vectors of WNV, Culex tarsalis and Culex pipiens, with irrigation methods (sprinkler vs. surface) and crop type (corn vs. soybean). Investigations were conducted …

Development Modeling Of Lucilia Sericata And Phormia Regina (Diptera: Calliphoridae), Amanda L. Roe

School of Natural Resources: Dissertations, Theses, and Student Research

The relationship between insect development and temperature has been well established and has a wide range of uses, including using blow flies for postmortem (PMI) interval estimations in death investigations. To use insects in estimating PMI, we must be able to determine the insect age at the time of discovery and backtrack to time of oviposition. Unfortunately, existing development models of forensically important insects are only linear approximations and do not take into account the curvilinear properties experienced at extreme temperatures. A series of experiments were conducted with two species of forensically important blow flies (Lucilia sericata and Phormia …

A Male Spider’S Ornamentation Polymorphism Maintained By Opposing Selection With Two Niches, Bo Deng, Alex Estes, Brett Grieb, Douglas Richard, Brittney Hinds, Eileen Hebets

Eileen Hebets Publications

The Levene mechanism to maintain genotypic polymorphism by opposing selection on genotypes in multiple niches was proposed 60 years ago, and yet no systems were found to satisfy the mechanisms rather restrictive conditions. Reported here is such an example that a wolf spider population lives in a habitat of mixed rocks and leafy litter for which the females are phenotypically indistinguishable and the males have two distinct phenotypes subject to opposing selection with respect to the substrates. Census data is best-fitted to a population genetics model of the Levene type. A majority of the best fit support polymorphism, with many …

Tactical Adjustment Of Signaling Leads To Increased Mating Success And Survival, Laura Sullivan-Beckers, Eileen A. Hebets

Eileen Hebets Publications

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioral solutions exist for overcoming such environmental variability, including the adjustment of signaling behavior based upon receiver feedback. Few studies have directly examined the relationship between such tactical signaling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following …

Mechanisms Of Differential Toxicity Between Honey Bee (Apis Mellifera L.) Castes With An Emphasis On Coumaphos, Lizette Dahlgren

Department of Entomology: Dissertations, Theses, and Student Research

Acaricides are used to treat honey bee (Apis mellifera L.) colonies to control the parasitic Varroa mite (Varroa destructor Anderson & Trueman), a worldwide threat to honey bee health. As such, these compounds act as drugs to mitigate bee losses but may also stress the bees. This dissertation quantifies differences between queen and worker tolerance of five acaricides and clarifies the honey bee mechanism of tolerance for coumaphos. Selected acaricides were topically applied to adult queen and worker bees to generate dose-response curves and LD₅₀s. Twenty-four hours after treatment, queens were 3-times more tolerant of tau-fluvalinate …

A Review Of New World Laemophloeus Dejean (Coleoptera: Laemophloeidae): 2. Neotropical Species With Antennal Club Of Three Antennomeres, Michael C. Thomas

Insecta Mundi

Eleven Neotropical species of Laemophloeus Dejean with antennal clubs composed of three antennomeres are reviewed, diagnosed, and illustrated. Six of the species are described as new: L. capitesculptus Thomas, n. sp., L. corporeflavus Thomas, n. sp., L. dozieri Thomas, n. sp., L. insulatestudinorum Thomas, n. sp., L. planaclavatus Thomas, n. sp., and L. taurus Thomas, n. sp. Four new synonymies are proposed: L. catharinensis Kessel (=L. incisus Sharp), new synonym; L. similans Kessel (=L. incisus Sharp), new synonym; L. distinguendus Sharp (=L. megacephalus Grouvelle), new synonym, and L. chevrolati …

Using Insects To Teach Stats: Creating Flipped Classroom Materials That Support Student Learning Of The Statistical Analysis Skills Requisite Within The International Baccalaureate Higher Level Biology Course Syllabus, John C. Gasparini

Department of Entomology: Distance Master of Science Projects

I work as a science teacher at a school in Germany. While I have enjoyed taking all of my classes within the UNL Masters in Entomology Program, I am not, and will not be a practicing entomologist in my career. That is why I would like my thesis project to focus on using the lessons that I have learned in completing this distance education program to improve my teaching.

I feel as if I learned a great deal about insects in this program, but in addition I also learned quite a bit about what works and what does not work …

Hexapod Herald - Vol. 26, No. 2, April 2014

Hexapod Herald and Other Entomology Department Newsletters

Contents: Welcome - Congratulations - Grants - Publications - Faculty News - Meet an Off-Campus Student - Student News - Bruner Club News - Meeting/Workshop News - Buzzing along - Calendar of Events

Molecular Evolution Of Glycoside Hydrolase Genes In The Western Corn Rootworm (Diabrotica Virgifera Virgifera), Seong-Il Eyun, Haichuan Wang, Yannick Pauchet, Richard H. Ffrench-Constant, Andrew K. Benson, Arnubio Valencia-Jimenez, Etsuko N. Moriyama, Blair Siegfried

Department of Entomology: Faculty Publications

Cellulose is an important nutritional resource for a number of insect herbivores. Digestion of cellulose and other polysaccharides in plant-based diets requires several types of enzymes including a number of glycoside hydrolase (GH) families. In a previous study, we showed that a single GH45 gene is present in the midgut tissue of the western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae). However, the presence of multiple enzymes was also suggested by the lack of a significant biological response when the expression of the gene was silenced by RNA interference. In order to clarify the repertoire of cellulose-degrading enzymes and related …

An Updated And Annotated Checklist Of The Larger Butterflies (Papilionoidea) Of Trinidad, West Indies: Papilionidae, Pieridae And Nymphalidae, Matthew J. W. Cock

Insecta Mundi

A revised checklist for the butterfly families Papilionidae, Pieridae and Nymphalidae of Trinidad (Trinidad and Tobago) is presented, bringing nomenclature in line with modern usage, indicating synonyms from earlier lists and adding new records since the last checklist was published in 1970. Migrant and vagrant species are provisionally recognised, and records considered incorrect are discussed. The checklist includes 204 species: 15 Papilionidae, 29 Pieridae and 160 Nymphalidae. The only taxonomic change is to treat Hamadryas feronia insularis (Fruhstorfer) as a synonym of H. f. feronia (Linnaeus), syn. nov., and not as a synonym of H. feronia farinulenta (Fruhstorfer).

A New Species Of Xylotrechus (Coleoptera: Cerambycidae: Clytini) From Utah, Ronald L. Alten

Insecta Mundi

Xylotrechus rameyi, new species, (Coleoptera: Cerambycidae) is described from southern Utah. Comments on its biology including habitat, host plants and larval history are provided along with photographs of the holotype, allotype, the related species X. insignis LeConte, and the larval galleries and pupal chamber.

Hexapod Herald - Vol. 26, No. 1, February 2014

Hexapod Herald and Other Entomology Department Newsletters

Content: Welcome - Congratulations - Grants - Publications - Meet an Off-Campus Student - Faculty News - Bruner Club News - Blasts from the Past - Condolences (Dr. John (Jack) Campbell) - Retirement Receptions