Genetics and Genomics Commons^™

Appendage Abnormalities In Spiders Induced By An Alternating Temperature Protocol In The Context Of Recent Advances In Molecular Spider Embryology, Teresa Napiorkowska, Julita Templin, Pawel Napiorkowski, Mark A. Townley

Faculty Publications

In the literature there are numerous reports of developmental deformities in arthropods collected in their natural habitat. Since such teratogenically affected individuals are found purely by chance, the causes of their defects are unknown. Numerous potential physical, mechanical, chemical, and biological teratogens have been considered and tested in the laboratory. Thermal shocks, frequently used in teratological research on the spider Eratigena atrica, have led to deformities on both the prosoma and the opisthosoma. In the 2020/2021 breeding season, by applying alternating temperatures (14 °C and 32 °C, changed every 12 h) for the first 10 days of embryonic development, …

Urbanization Affects Web Abundance And Aggregation Of A Funnel‑Weaving Spider, Agelenopsis Pennsylvanica (Agelenidae), Brandi J. Pessman, Madison Hays, Earl Agpawa, Eileen Hebets

Eileen Hebets Publications

Animals distribute themselves within habitats based on a variety of environmental conditions, including those impacted by urbanization. Suspected global declines in urban arthropod biodiversity have required that we examine how urban conditions affect the distribution of this ecologically important group. Throughout North America, funnel-weaving spiders (Agelenidae) are prevalent across urban habitats and actively choose sites to build webs. We compared Agelenopsis pennsylvanica abundance and distribution between two distinct urban habitats: an urban center (university campus) and an urban forest (city park). These urban habitats differed significantly in features like plant diversity and proximity to roads and highways. We searched along …

Additional Taxonomic Refinements Suggested By Genomic Analysis Of Butterflies, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Paul A. Opler, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Comparative analyses of genomic data reveal further insights into the phylogeny and taxonomic classification of butterflies presented here. As a result, 2 new subgenera and 2 new species of Hesperiidae are described: Borna Grishin, subgen. n. (type species Godmania borincona Watson, 1937) and Lilla Grishin, subgen. n. (type species Choranthus lilliae Bell, 1931) of Choranthus Scudder, 1872, Cecropterus (Murgaria) markwalkeri Grishin, sp. n. (type locality in Mexico: Sonora), and Hedone yunga Grishin, sp. n. (type locality in Bolivia: Yungas, La Paz). The lectotype is designated for Aethilla toxeus Plötz, 1882. The type locality of Dion uza (Hewitson, 1877) is likely …

Diversity In Darkness: Shedding Light On Cryptic Species In The Cave Beetle Genus Darlingtonea Valentine Using 3rad Sequencing And Consequences Of Climate Change Based On Thermal Tolerance And Dehydration Resistance, Athanasios S. Apostolopoulos

Masters Theses & Specialist Projects

The relationship between geographic distribution and phylogeny is pronounced in patchy, discontinuous habitats that limit gene flow, such as cave ecosystems. The isolating nature and selective pressures of cave environments can result in relatively high levels of endemism and cryptic speciation in cave faunas. Cryptic speciation exhibited in cave faunas is poorly studied, though it is an integral aspect to consider when discussing conservation efforts.

Our study employed the 3RAD genomic sequencing technique and robust population sampling across the distribution of a monotypic genus of cave beetle, Darlingtonea Valentine, that inhabits karst systems in a nearly 200 square mile range …

Increased Signal Complexity Is Associated With Increased Mating Success, Noori Choi, Matt Adams, Kasey Fowler-Finn, Elise Knowlton, Malcolm Rosenthal, Aaron Rundus, Roger D. Santer, Dustin J. Wilgers, Eileen Hebets

Eileen Hebets Publications

The evolution of complex signals has often been explored by testing multiple functional hypotheses regarding how independent signal components provide selective benefits to offset the costs of their production. In the present study, we take a different approach by exploring the function of complexity per se. We test the hypothesis that increased vibratory signal complexity— based on both proportional and temporal patterning—provides selective benefits to courting male Schizocosa stridulans wolf spiders. In support of this hypothesis, all of our quantified metrics of vibratory signal complexity predicted the mating success of male S. stridulans. The rate of visual signalling, which is …

Description Of The Courtship And Copulation Behaviours Of The Wall Spider Oecobius Concinnus (Oecobiidae), Diego Solano-Brenes, Laura Segura-Hernández, Gilbert Barrantes

Eileen Hebets Publications

Courtship and copulation behaviours are yet scantily described in many spider families, and this lack of information limits our understanding of the evolution of such behaviours within and across families. Here, we provide a detailed description of both courtship and copulation behaviour for Oecobius concinnus Simon, 1893. A striking characteristic of the male courtship is the construction of a tubular web (mating web) in which most courtship and copulation occurs. This web likely functions to restrain the female in a reduced space and as a substrate for male pheromones. The courtship consists of a complex web of interactions between both …

Two New Species Of Byrrhinus Motschulsky, 1858 (Coleoptera, Limnichidae, Limnichinae) From Negros, Philippines, Emmanuel D. Delocado, Hendrik Freitag

Biology Faculty Publications

Two new species of Limnichidae beetles, Byrrhinus negrosensis sp. nov. and Byrrhinus villarini sp. nov., are described from the Island of Negros in the Philippines. The adult specimens of the new species can be differentiated by patterns of body punctation, colour and orientation of elytral pubescence, posterolateral angle of pronotum, tarsomere length ratio and aedeagal form. Two clades, representing the two new species, were retrieved in the Maximum Likelihood gene tree using the 3’-end of the COI gene. Maximum genetic divergence within B. negrosensis sp. nov. and B. villarini sp. nov. were recorded to be 2.3% and 1.3%, respectively, while …

Foe To Friend: Parallel Domestication Of Ophiocordyceps From Fungal Parasite To Beneficial Symbiont In Cicadas, Jason Vailionis, Eric Rl Gordon, Chris Simon

University Scholar Projects

Nutritional symbioses are integral to the survival and diversity of many insects. The majority of herbivorous insects in the order Hemiptera possess stable, inherited symbionts that produce essential amino acids and vitamins. However, instability has been observed in cicadas, with one bacterial symbiont, Hodgkinia cicadicola, being repeatedly replaced by a new fungal symbiont, Ophiocordyceps. The fungal symbionts are thought to be derived from parasitic Ophiocordyceps species, but little is known about these parasitic ancestors or how the transition from parasite to mutualist occurs. We used a combination of targeted amplified genes and metagenomic sequencing to investigate the evolution …

Changes In Both Trans- And Cis-Regulatory Elements Mediate Insecticide Resistance In A Lepidopteron Pest, Spodoptera Exigua, Bo Hu, He Huang, Songzhu Hu, Miaomiao Ren, Qi Wei, Xiangrui Tian, Mohammed Esmail Abdalla Elzaki, Chris Bass, Jianya Su, Subba Reddy Palli

Entomology Faculty Publications

The evolution of insect resistance to insecticides is frequently associated with overexpression of one or more cytochrome P450 enzyme genes. Although overexpression of CYP450 genes is a well-known mechanism of insecticide resistance, the underlying regulatory mechanisms are poorly understood. Here we uncovered the mechanisms of overexpression of the P450 gene, CYP321A8 in a major pest insect, Spodoptera exigua that is resistant to multiple insecticides. CYP321A8 confers resistance to organophosphate (chlorpyrifos) and pyrethroid (cypermethrin and deltamethrin) insecticides in this insect. Constitutive upregulation of transcription factors CncC/Maf are partially responsible for upregulated expression of CYP321A8 in the resistant strain. Reporter gene assays …

Spatio-Temporal Selection Of Reference Genes In The Two Congeneric Species Of Glycyrrhiza, Yuping Li, Xiaoju Liang, Xuguo Zhou, Yu An, Ming Li, Ling Yuan, Yongqing Li, Ying Wang

Entomology Faculty Publications

Glycyrrhiza, a genus of perennial medicinal herbs, has been traditionally used to treat human diseases, including respiratory disorders. Functional analysis of genes involved in the synthesis, accumulation, and degradation of bioactive compounds in these medicinal plants requires accurate measurement of their expression profiles. Reverse transcription quantitative real-time PCR (RT-qPCR) is a primary tool, which requires stably expressed reference genes to serve as the internal references to normalize the target gene expression. In this study, the stability of 14 candidate reference genes from the two congeneric species G. uralensis and G. inflata, including ACT, CAC, CYP, …

De Novo Whole Genome Assembly Of The Swede Midge (Contarinia Nasturtii), A Specialist Of Brassicaceae, Using Linked-Read Sequencing, Boyd A. Mori, Cathy Coutu, Yolanda H. Chen, Erin O. Campbell, Julian R. Dupuis, Martin A. Erlandson, Dwayne D. Hegedus

Entomology Faculty Publications

The swede midge, Contarinia nasturtii, is a cecidomyiid fly that feeds specifically on plants within the Brassicaceae. Plants in this family employ a glucosinolate-myrosinase defense system, which can be highly toxic to non-specialist feeders. Feeding by C. nasturtii larvae induces gall formation, which can cause substantial yield losses thus making it a significant agricultural pest. A lack of genomic resources, in particular a reference genome, has limited deciphering the mechanisms underlying glucosinolate tolerance in C. nasturtii, which is of particular importance for managing this species. Here, we present an annotated, scaffolded reference genome of C. nasturtii using linked-read …

Physical Mapping Of The Anopheles (Nyssorhynchus) Darlingi Genomic Scaffolds, Míriam Silva Rafael, Leticia Cegatti Bridi, Igor V. Sharakhov, Osvaldo Marinotti, Maria V. Sharakhova, Vladimir A. Timoshevskiy, Giselle Moura Guimarães-Marques, Valéria Silva Santos, Carlos Gustavo Nunes Da Silva, Spartaco Astolfi-Filho, Wanderli Pedro Tadei

Biology Faculty Publications

The genome assembly of Anopheles darlingi consists of 2221 scaffolds (N50 = 115,072 bp) and has a size spanning 136.94 Mbp. This assembly represents one of the smallest genomes among Anopheles species. Anopheles darlingi genomic DNA fragments of ~37 Kb were cloned, end-sequenced, and used as probes for fluorescence in situ hybridization (FISH) with salivary gland polytene chromosomes. In total, we mapped nine DNA probes to scaffolds and autosomal arms. Comparative analysis of the An. darlingi scaffolds with homologous sequences of the Anopheles albimanus and Anopheles gambiae genomes identified chromosomal rearrangements among these species. Our results confirmed that physical mapping …

Solifuge (Camel Spider) Reproductive Biology: An Untapped Taxon For Exploring Sexual Selection, Alfredo V. Peretti, David E. Vrech, Eileen Hebets

Eileen Hebets Publications

The exploration of new and diverse animal groups in the study of sexual selection is both necessary and important to help better understand broad patterns and test sexual selection hypotheses regarding the evolutionary origins and maintenance of reproductive tactics and associated traits. Solifuges are, in this matter, an exceptional group and very little explored from the sexual selection point of view. At first glance, mating is apparently quite simple and conserved within this arachnid order, but solifuge reproductive behavior is unique among arachnids and more diverse than previously thought. In particular, these voracious animals appear to exhibit high sexual conflict, …

Spiders (Araneae) Collected As Prey By The Mud-Dauber Wasps Sceliphron Caementarium And Chalybion Californicum (Hymenoptera: Sphecidae) In Southeastern Nebraska1, Tyler B. Corey, Earl Agpawa, Eileen Hebets

Eileen Hebets Publications

Predator diets represent a potential interaction between local prey availability, prey antipredator defenses, and predator foraging behavior. Female spider-specialist muddauber wasps (Hymenoptera: Sphecidae) collect spiders and provision them intact, but paralyzed, to their developing larvae, providing a unique means of quantifying the diversity and abundance of prey that they capture. Mud-dauber wasps are hypothesized to be a major source of selection on antipredator defenses in web-building spiders, and the spiny and thickened abdomens of female spiny orb-weaving spiders (Araneae: Araneidae) are hypothesized to function as antiwasp defenses. We inventoried spider prey from nests of the mud-dauber wasps Sceliphron caementarium (Drury) …

Up-Regulation Of Apoptotic- And Cell Survival-Related Gene Pathways Following Exposures Of Western Corn Rootworm To B. Thuringiensis Crystalline Pesticidal Proteins In Transgenic Maize Roots, Brad S. Coates, Emeline Deleury, Aaron J. Gassmann, Bruce E. Hibbard, Lance Meinke, Nicholas J. Miller, Jennifer L. Petzold-Maxwell, B. Wade French, Thomas W. Sappington, Blair D. Siegfried, Thomas Guillemaud

Department of Entomology: Faculty Publications

Background: Resistance of pest insect species to insecticides, including B. thuringiensis (Bt) pesticidal proteins expressed by transgenic plants, is a threat to global food security. Despite the western corn rootworm, Diabrotica virgifera virgifera, being a major pest of maize and having populations showing increasing levels of resistance to hybrids expressing Bt pesticidal proteins, the cell mechanisms leading to mortality are not fully understood.

Results: Twenty unique RNA-seq libraries from the Bt susceptible D. v. virgifera inbred line Ped12, representing all growth stages and a range of different adult and larval exposures, were assembled into a reference transcriptome. Ten-day exposures …

Multisensory Integration Supports Configural Learning Of A Home Refuge In The Whip Spider Phrynus Marginemaculatus, Kaylyn A.S. Flanigan, Daniel D. Wiegmann, Eileen Hebets, Verner Peter Bingman

Eileen Hebets Publications

Predator diets represent a potential interaction between local prey availability, prey antipredator defenses, and predator foraging behavior. Female spider-specialist muddauber wasps (Hymenoptera: Sphecidae) collect spiders and provision them intact, but paralyzed, to their developing larvae, providing a unique means of quantifying the diversity and abundance of prey that they capture. Mud-dauber wasps are hypothesized to be a major source of selection on antipredator defenses in web-building spiders, and the spiny and thickened abdomens of female spiny orb-weaving spiders (Araneae: Araneidae) are hypothesized to function as antiwasp defenses. We inventoried spider prey from nests of the mud-dauber wasps Sceliphron caementarium (Drury) …

Visual Control Of Refuge Recognition In The Whip Spider Phrynus Marginemaculatus, Kaylyn A.S. Flanigan, Daniel D. Wiegmann, Patrick Casto, Vincent J. Coppola, Natasha R. Flesher, Eileen Hebets, Verner Peter Bingman

Eileen Hebets Publications

Amblypygids, or whip spiders, are nocturnally active arachnids which live in structurally complex environments. Whip spiders are excellent navigators that can re-locate a home refuge without relying on visual input. Therefore, an open question is whether visual input can control any aspect of whip spider spatial behavior. In the current study, Phrynus marginemaculatus were trained to locate an escape refuge by discriminating between differently oriented black and white stripes placed either on the walls of a testing arena (frontal discrimination) or on the ceiling of the same testing arena (overhead discrimination). Regardless of the placement of the visual stimuli, the …

Identification And Quantification Of 11 Airborne Biochemicals Emitted By The Brown Recluse And Another Primitive Hunting Spider Using Headspace Solid-Phase Microextraction-Gc/Ms, Zachary Foulks, Jennifer Parks, William Stoecker, Charles Kristensen, Eileen A. Hebets, Honglan Shi

Eileen Hebets Publications

Loxosceles reclusa, or brown recluse spider, is a harmful household spider whose habitat extends throughout the Midwest in the USA and other regions in the world. The pheromones and other biomolecules that facilitate signaling for brown recluses and other spider species are poorly understood. A rapid and sensitive method is needed to analyze airborne spider signaling biomolecules to better understand the structure and function of these biochemicals in order to control the population of the spiders. In this study, we developed a novel headspace solid-phase microextraction (HS-SPME)-GC/MS method to analyze potential pheromones and biomolecules emitted by the brown recluse …

Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Pennsylvania Baptisia australis var. australis is restricted to is also in decline and considered vulnerable. Because of these conservation concerns, insights into the natural history of the taxon in the state is valuable and will inform conservation efforts. Field surveys and fruit collections along the Allegheny River and herbarium collections were used …

Ogre-Faced, Net-Casting Spiders Use Auditory Cues To Detect Airborne Prey, Jay A. Stafstrom, Gil Menda, Eya I. Nitzany, Eileen A. Hebets, Ronald R. Hoy

Eileen Hebets Publications

Prey-capture behavior among spiders varies greatly from passive entrapment in webs to running down prey items on foot. Somewhere in the middle are the ogre-faced, net-casting spiders (Deinopidae: Deinopis) that actively capture prey while being suspended within a frame web. Using a net held between their front four legs, these spiders lunge downward to ensnare prey from off the ground beneath them. This “forward strike” is sensorially mediated by a massive pair of hypersensitive, night-vision eyes. Deinopids can also intercept flying insects with a “backward strike,” a ballistically rapid, overhead back-twist, that seems not to rely on visual cues. Past …

Exploring A Novel Substrate-Borne Vibratory Signal In The Wolf Spider Schizocosa Floridana, Malcolm F. Rosenthal, Eileen Hebets, Rowan H. Mcginley, Cody Raiza, James Starrett, Lin Yan, Damian O. Elias

Eileen Hebets Publications

Animals communicate using a diversity of signals produced by a wide array of physical structures. Determining how a signal is produced provides key insights into signal evolution. Here, we examine a complex vibratory mating display produced by male Schizocosa floridana wolf spiders. This display contains three discrete substrate-borne acoustic components (known as “thumps”, “taps”, and “chirps”), each of which is anecdotally associated with the movement of a different body part (the pedipalps, legs, and abdomen respectively). In order to determine the method of production, we employ a combination of high-speed video/audio recordings and SEM imaging of possible sound-producing structures. Previous …

Testing The Hypothesized Antipredator Defence Function Of Stridulation In The Spiny Orb-Weaving Spider, Micrathena Gracilis, Tyler B. Corey, Eileen A. Hebets

Eileen Hebets Publications

The observable diversity of antipredator defenses across organisms demonstrates predation’s impact on trait evolution. The functions of many traits that are presumed to have an antipredator function have never been directly tested. The spiny orb-weaving spider, Micrathena gracilis, for example, stridulates when grasped. While stridulation was first hypothesized to be an antipredator defense nearly 50 years ago, no data exist to support this hypothesis. To explore the form and function of M. gracilis stridulation, we first quantified the behavioral and acoustical properties of sound production. Next, using laboratory assays, we directly tested the effect of stridulation on survival with …

A Deeper Meaning For Shallow-Level Phylogenomic Studies: Nested Anchored Hybrid Enrichment Offers Great Promise For Resolving The Tiger Moth Tree Of Life (Lepidoptera: Erebidae: Arctiinae), Nicolas J. Dowdy, Shannon Keating, Alan R. Lemmon, Emily M. Lemmon, William E. Conner, Clare H. Scott Chialvo, Susan Weller, Rebecca B. Simmons, Melissa S. Sisson, Jennifer M. Zaspel

Department of Entomology: Faculty Publications

Anchored hybrid enrichment (AHE) has emerged as a powerful tool for uncovering the evolutionary relationships within many taxonomic groups. AHE probe sets have been developed for a variety of insect groups, though none have yet been shown to be capable of simultaneously resolving deep and very shallow (e.g., intraspecific) divergences. In this study, we present NOC1, a new AHE probe set (730 loci) for Lepidoptera specialized for tiger moths and assess its ability to deliver phylogenetic utility at all taxonomic levels. We test the NOC1 probe set with 142 individuals from 116 species sampled from all the major lineages of …

Distortion Of The Local Magnetic Field Appears To Neither Disrupt Nocturnal Navigation Nor Cue Shelter Recognition In The Amblypygid Paraphrynus Laevifrons, Daniel D. Wiegmann, Patrick Casto, Eileen Hebets, Verner P. Bingman

Eileen Hebets Publications

Many arthropods are known to be sensitive to the geomagnetic field and exploit the field to solve spatial problems. The polarity of the geomagnetic field is used, for instance, as an orientation cue by leafcutter ants as they travel on engineered trails in a rainforest and by Drosophila larvae as they move short distances in search of food. A ubiquitous orientation cue like the geomagnetic field may be especially useful in complex, cluttered environments like rainforests, where the reliability of celestial cues used to navigate in more open environments may be poor. The neotropical amblypygid Paraphrynus laevifrons is a nocturnal …

Delineation Of Undescribed, Morphologically Cryptic Cave Beetles Of The Pseudanophthalmus Pubescens Species-Group (Coleoptera: Carabidae: Trechinae), Jedidiah John Nixon

Masters Theses & Specialist Projects

The genus Pseudanophthalmus Jeannel is a widespread and extremely diverse taxon of troglobiont beetle endemic to the karst of eastern North America, with its distribution centered in Tennessee and Kentucky. Despite lying near the heart of this region, the pubescens species-group was thought to contain many undescribed species. In this study, the validities of several of the late Dr. Thomas Barr’s unpublished putative new species in the pubescens-group were tested both morphologically and molecularly. Body measurements (length and width for head, thorax, and abdomen), as well as male genital morphology were compared to see if they reflected theorized species limits.. …

An Intergrative Ecological And Taxonomic Assessment Of The Stoneflies (Insecta, Plecoptera) Of The Black Mountains, North Carolina, Usa, Madeline Lake Metzger

Masters Theses & Specialist Projects

The Black Mountains are a part of the Blue Ridge region of the Appalachian Mountains and include Mount Mitchell, the highest peak east of the Mississippi River at 2,037 m (= 6,684 ft). A comprehensive inventory of the stonefly fauna was conducted between 2014-2019 within Mt. Mitchell State Park and adjacent Pisgah National Forest. Collections occurred seasonally from 44 unique locations, covering a broad range of stream sizes and elevations in the region. Sequencing of the mitochondrial cytochrome c oxidase subunit I (mtCOI) gene was completed to assist with making positive determinations to species for females of taxonomically challenging genera …

Vertical‑Surface Navigation In The Neotropical Whip Spider Paraphrynus Laevifrons (Arachnida: Amblypygi), Patrick Casto, Daniel D. Wiegmann, Vincent J. Coppola, Daniele Nardi, Eileen A. Hebets, Verner P. Bingman

Eileen Hebets Publications

Studies on whip spider navigation have focused on their ability to locate goal locations in the horizontal plane (e.g., when moving along the ground). However, many species of tropical whip spiders reside and move along surfaces in the vertical plane (e.g., trees). Under controlled laboratory conditions, the current study investigated the ability of the tropical whip spider, Paraphrynus laevifrons, to return to a home shelter on a vertical surface in the presence of numerous, similar, and competing refuge sites, as well as the distribution of navigational errors in the vertical, horizontal, and diagonal plane. We also assessed the relative …

Demonstrating Mate Choice Copying In Spiders Requires Further Research, R. Tucker Gilman, Kasey Fowler-Finn, Eileen A. Hebets

Eileen Hebets Publications

Mate choice copying—when individuals learn to prefer mates or mate types that have been chosen by others—can influence trait evo-lution and speciation (Varela et al. 2018; Dion et al. 2019). Most examples of mate choice copying are from fish, birds, and mammals including humans (Varela et al. 2018). However, 2 invertebrate examples—fruit flies and wolf spiders—have been used to argue that the phenomenon may be phylogenetically widespread, and perhaps the rule rather than the exception in nature (Varela et al. 2018). Here, we revisit the evidence for mate choice copying in wolf spiders (Fowler-Finn et al. 2015) in light of …

Geographic Distribution Of Bacillus Thuringiensis Cry1f Toxin Resistance In Western Bean Cutworm (Lepidoptera: Noctuidae) Populations In The United States, Brad S. Coates, Craig A. Abel, Katharine A. Swoboda-Bhattarai, Debra E. Palmquist, Débora Goulart Montezano, Sarah N. Zukoff, Yangzhou Wang, Jeffery D. Bradshaw, Christina D. Difonzo, Elson Shields, Kelley J. Tilmon, Thomas Hunt, Julie A. Peterson

West Central Research and Extension Center, North Platte

The western bean cutworm (WBC), Striacosta albicosta (Lepidoptera: Noctuidae), can be a severe pest of transgenic corn in the western Plains and Great Lakes regions of North America, including on hybrids expressing the Bacillus thuringiensis (Bt) Cry1F toxin. The level and geographic distribution of Cry1F resistance are not completely known. Neonate S. albicosta from 10 locations between Nebraska and New York state were subjected to dose–response trypsin-activated native Cry1F toxin overlay bioassays. In 2017, the mean estimated lethal concentration causing 50% larval mortality (LC50) ranged from 15.1 to 18.4 μg Cry1F cm−2, and were not significantly different among locations. In …

Transcriptional Responses Of Soybean Aphids To Sublethal Insecticide Exposure, Laramy S. Enders, Leslie C. Rault, Tiffany Heng-Moss, Blair Siegfried, Nicholas J. Miller

Department of Entomology: Faculty Publications

Insecticides are a key tool in the management of many insect pests of agriculture, including soybean aphids. The selection imposed by insecticide use has often lead to the evolution of resistance by the target pest through enhanced detoxification mechanisms. We hypothesised that exposure of insecticide-susceptible aphids to sublethal doses of insecticides would result in the up-regulation of genes involved in detoxification of insecticides, revealing the genes upon which selection might act in the field. We used the soybean aphid biotype 1 reference genome, version 6.0 as a reference to analyze RNA-Seq data. We identified multiple genes with potential detoxification roles …