Entomology Commons^™

Wolbachia Infection In Gall Associated Insect Communities In Illinois And Indiana, Jakeb Watts

Masters Theses

Wolbachia is a maternally inherited, gram-negative bacterium and has been found to be associated with up to 60% of all insects, frequently resulting in male-killing, feminization, and cytoplasmic incompatibility in the hosts. Gall wasps and other gall-forming insects induce on various host plants abnormal tissue growths, or plant galls, with distinct morphology. They are considered as obligatory parasites to their host plant. The presence of Wolbachia infection in gall wasp populations in North America has not been extensively documented. Given the strong influence on host reproduction, not knowing Wolbachia infection in insect populations prevents the understanding of how populations are …

Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina

Masters Theses

Human body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, have been hematophagous ectoparasites of humans for thousands of years. Despite being ecotypes, only body lice are known to transmit bacterial diseases to humans, and it appears that lower humoral and cellular immune responses allow body lice to possess a higher vector competence. We previously observed that the transcription level of the defensin 1 gene was up-regulated only in head lice following oral challenge of Bartonella quintana, a causative agent of trench fever, and also that body lice excreted more viable B. quintana in their …

Evaluation Of Insecticide Resistance In Populations Of Tobacco Thrips, Frankliniella Fusca (Hinds), And Plant Density Effects On Thrips Injury To Cotton, Jessica L. Krob

Masters Theses

Two field studies were performed in Tennessee to evaluate the effects of plant density and seed spacing on thrips injury to upland cotton (Gossypium hirsutum L.). The plant density study consisted of seeding rate treatments that were low, normal, high, and very high, relative to university Extension recommendations. In the plant spacing study, treatments were implemented using nearly identical seeding rates but with relatively uniform seed spacing versus a clumped, “hill-dropped” spacing. In both studies, the seed was either treated with an insecticide (imidacloprid) and a fungicide or only with a fungicide. Due to variable environmental conditions, the results …

Effects Of Land-Use And Disturbance On Pollinators In Wetlands, Nicholas V. Oldham

Masters Theses

While pollinators and wetlands both provide important ecosystem services (e.g., the pollination of flowering plants and improving water quality), the relationship between the two is not well understood. Wetland quality can determine the local floral community, which likely mediates local pollinator populations. In this study, we investigated how land-use, including a gradient of urban development at the landscape scale, and anthropogenic disturbance affects pollinators in wetlands. We surveyed the abundance and diversity of plant communities in a range of different wetlands across two years. We also measured abiotic factors, such as water quality, light availability, and temperature for insights into …

Evaluating The Ecological Relationships Among Beauveria Bassiana, Kudzu Bug And Kudzu, Kassie L. Hollabaugh

Masters Theses

When kudzu bug, Megacopta cribraria, was identified in the United States in 2009 as an invasive species, populations began to establish, increase, and spread throughout the southeastern region at intense rates. Kudzu bug invades urban structures, causing unpleasant scenes for homeowners, and reduces crop yield, such as soybean. Kudzu bug caused about $2.8 million in soybean yield loss and treatment in Tennessee in 2020. Although initial spread was rapid throughout the southeastern U.S., spatial modeling has shown populations of kudzu bug are declining and reducing risk of crop damage to growers. These local and regional declines in populations appear …

Songbird-Mediated Insect Pest Control In Low Intensity New England Agriculture, Samuel J. Mayne

Masters Theses

Global agricultural intensification has caused large-scale wildlife declines, but agricultural lands that maintain natural habitats can support healthy wildlife populations and receive significant ecosystem services from these natural communities. However, how on-farm biodiversity results in beneficial ecosystem services is highly variable and is reported to differ among taxa and guilds. One group that has attracted attention for their potential beneficial role in reducing pest abundance are birds. Understanding the role of bird communities and individual species in pest control could be important for managing farms under a low intensity agroecological framework. In New England, farmers are increasingly applying low intensity …

Deciphering The Role Of Mitochondrial Physiology And Thermal Acclimation In Shaping Whole Organismal Performance Of An Invasive Forest Pest, Essa Alrashdi

Masters Theses

Environmental factors such as temperature are substantial determinants of the spongy moth, L. dispar, distribution, reproduction, and growth. Accumulating energy reserves at the larval stage is particularly important to L. dispar, since the larvae metamorphose into a fully-grown, non-feeding adult. As non-feeding adults, the energy balance of the pupae must be adequate, to ensure enough energy reserves for adult dispersal, egg maturation and overall persistence of the species in the region. At this stage, environmental temperature also determines daily metabolic demands, and the overall cost of sustaining ecologically relevant activities. Various hypotheses describing a mismatched growth and metabolic …

Comparing Macroinvertebrate Total Abundance And Total Biomass On Five Substrate Types From Upstream To Downstream On The North Branch Of The Au Sable River, Paul David Dingman

Masters Theses

The North Branch of the Au Sable River is located in the northern lower peninsula of Michigan and is known for prolific hatches of Ephemeroptera (mayflies), Trichoptera (caddisflies), and Plecoptera (stoneflies). Macroinvertebrates play an important role in processing and recycling organic material in rivers and are a valuable food source for trout. In 2018, anglers were reporting catching fewer numbers of brook and brown trout (Salmo trutta and Salvelinus fontinalis). The Michigan Department of Natural Resources (MDNR) determined significantly lower abundance than the historical average. We hypothesized that trout abundances were lower due to a lack of prey …

Seasonality, Distribution, And Biological Control Of Crapemyrtle Bark Scale, A New Invasive Threat In Tennessee, Amira Cornish

Masters Theses

Crapemyrtle bark scale, Acanthococcus (= Eriococcus) lagerstroemiae (Kuwana), an invasive pest from Asia, is a threat in the United States. to crape myrtles grown in ornamental nurseries and in landscapes. Although mortality to crape myrtles is rare, its negative effects on aesthetics is considerable. It should affect the sale (valued at >$66 million wholesale) and use of crape myrtle in landscapes. This pest species has been found in numerous states, including Tennessee, where little is known about its state-wide distribution, lifecycle, biology, natural enemies, and impact on crape myrtles. The purpose of this two-year study is to gain additional knowledge …

Feeding Behavior And Influence Of Hemp Varieties And Fertilization Rates On Damage Caused By Corn Earworm, Helicoverpa Zea, Julian Cosner

Masters Theses

Production of industrial hemp, Cannabis sativa L., has increased tremendously in the U.S. after its legalization through the Agricultural Improvement Act of 2018, known as the 2018 Farm Bill, which allowed commercial hemp production. By grower number, in 2020, Tennessee was the nation’s largest hemp program with over 1,800 producers licensed to grow up to 6,500 hectares (16,000 acres) according to the Tennessee Department of Agriculture. Though fiber and seed have a role in the industry, most growers (ca. 98%) concentrate on cannabidiol production because of the expected higher cash value potential per hectare. Introducing hemp as a monocrop system …

Pollinator Community Homogenization And Pollination Services In Agroecosystems, Devon S. Eldridge .

Masters Theses

Pollination, or the transfer of pollen to plant stigmas, is an essential part of plant reproduction. The term “pollination system” refers to the floral phenotype and pollinator of a given plant. Although angiosperms exhibit a variety of different pollination systems, most rely partially or completely on animals, particularly insects, to vector their pollen. In agricultural systems, understanding the pollination system of the crop species is necessary to produce an economically valuable yield. Moreover, agricultural management may affect pollination systems by altering the abundance, diversity, or function of the pollinator community. In natural ecosystems, there is a great diversity of pollinating …

Supplementing East Tennessee Landscapes For Pollinators With Native Perennials, Amani Khalil

Masters Theses

Tennessee, home to the Great Smoky Mountains, is a biodiversity hotspot for many plant and animal species, yet it receives relatively few conservation dollars (Jenkins et al., 2015). As a biodiversity hotspot, this region may be home to many endemic species, but little is known about the abundance or diversity of insect pollinators. In order to both estimate pollinator communities in East Tennessee and pollinator forage preferences for native Tennessee plants, we established four plots, comprised of three plant families across five common land use types. Over two field seasons we collected nearly 7,300 insect specimens with a total sampling …

Impact Of Predators On Hemlock Woolly Adelgid (Hemiptera: Adelgidae) In The Eastern And Western United States, Ryan Crandall

Masters Theses

Hemlock woolly adelgid, Adelges tsugae, native to Asia and the Pacific Northwest of North America (Pacific Northwest), has devastated eastern hemlock (Tsuga canadensis) in a major portion of its range in the eastern U.S. After many years and much effort directed towards rearing and releasing biological control agents to manage HWA, one of these agents, Laricobius nigrinus, native to the Pacific Northwest, is now well-established in sites from the southern to the mid-Atlantic states of the eastern U.S. However, there have yet to be studies of its efficacy in lowering A. tsugae densities, and there has …

Defining Bee Pollinator Community Composition In Tennessee Soybean, Andrew L. Lawson

Masters Theses

Two planting dates of various soybean varieties were planted in Jackson and Knoxville, TN during 2018 and 2019 with the overall intent of surveying the diversity bee (Hymenoptera) genera in these agroecosystems and also to assess the potential for using late maturing soybean as a food resource for bees during the dearth of floral resources that often occurs during the fall. We also investigated how manipulating planting dates and soybean variety selection affected the occurrence of insect pests that occurred in the soybean.

Both active (netting) and passive (bee bowls and blue-vane traps) sampling were used to collect the bees, …

Influence Of Traditional And Dual-Use Cropping On Arthropods And Slugs In Soybean In Tennessee, Matthew L. Longmire

Masters Theses

Soybean is the number one agricultural crop in Tennessee for both number of hectares planted and economic value. Soybean, used in various products, is marketed globally. In recent years, Tennessee soybean growers have shown an increased interest in the use of cover crops with soybean. A cover crop is planted before the cash crop and can minimize some weeds, diseases, insects, and other pests. Traditionally, cover crops are terminated in the spring before cash crop planting. Traditional methods of cover cropping provide many benefits but can also produce some undesired results. Dual-use cover cropping is a newer method of cover …

Helicoverpa Zea (Boddie) (Lepidoptera: Noctuidae) Larval Distribution On Different Bt Technologies And Evaluating Cotton Plant Tissue Assays For Resistance Monitoring, Dawson David Kerns

Masters Theses

Field trials were conducted in 2018 at the West Tennessee Research and Education Center (WTREC) in Jackson, TN and in 2019 at locations in College Station, TX, Tillar, AR, and Jackson, TN. Non-Bt, Cry1Ac + Cry1F, and Cry1Ac + Cry2Ab cotton varieties were either treated with an insecticide or left untreated. After five days, cotton plants were mapped for signs of bollworm, Helicoverpa zea (Lepidoptera: Noctuidae), feeding on floral structures (i.e., bolls, squares, flowers) and the physical presence of larvae. Bt technologies reduced the number of H. zea larvae and the amount of feeding injury, but no major differences in …

Effects Of Chemical Variation On Competition And Insect Communities Across Solidago Altissima Genotypes, Bryan Scott Foster Ii

Masters Theses

Individuals within a plant species can differ greatly from one another, especially regarding the range of chemical compounds produced. However, the functions of many of these chemicals are unknown, but likely include defenses against herbivores, attractants for pollinators and seed dispersers, as well as mechanisms for resource competition. To assess the effects of foliar chemical composition on interspecific plant competition and insect communities, I conducted a common garden and greenhouse experiment using 24 genotypes of the allelopathic species Solidago altissima for which the foliar chemistry had been characterized. Using these data and chemical profiles of S. altissima, I linked …

Effects Of Insect Opportunists On A Four-Level Trophobiotic System Involving Nectar-Producing Galls Of The Cynipid Wasp Disholcaspis Quercusmamma (Hymenoptera: Cynipidae), Stephanie L. Smith

Masters Theses

The induction of plant galls is considered an adaptive life history trait found in many insect groups. The formation of galls provides several advantages to the gall maker, such as enhanced nutrition, favorable microclimate, and protection from natural enemies, including parasitoids, inquilines, and predators. Order Hymenoptera has many gall-making species, belonging to the gall wasp family Cynipidae. As an extended phenotype of the gall makers, some galls exhibit very sophisticated adaptive mechanisms involving multilevel species interactions. In particular, the oak galls of the Cynipid species Disholcaspis quercusmamma, found in much of Illinois, produce a palatable, sugary nectar-like secretion, attracting …

Visual Attention In Jumping Spiders, Margaret Bruce

Masters Theses

The different ways that animals extract and analyze visual information from their environment is of interest to sensory ecologists. Jumping spiders, well-known for visually guided mating and hunting behavior, are an interesting model for the study of visual attention because they quickly and efficiently integrate information from eight eyes with a small brain. Stimuli in front of the spider are examined by two functionally and morphologically distinct pairs of forward-facing eyes. The principal eyes discern fine details and have small retinas and thus a small visual field. However, their position at the back of moveable tubes within the cephalothorax expands …

Haplotype Diversity And Population Genetic Structure Of Antistrophus Gall Wasps Associated With Two Silphium Species And Implication For Host Mediated Speciation, Jiaxin Deng

Masters Theses

Gall making insects form a special feeding guild of phytophagous animals, and by manipulating host plant tissue differentiation, are able to avoid plant chemical defenses and thus have no need for counter defense mechanisms. Host plant selection is crucial to the evolution of these insects because successful gall formation is largely dependent on host plant ability to respond to stimuli. In Illinois and neighboring states, Antistrophus gall wasps associated with the rosin weed (S. integrifolium) and the cup plant (S. perfoliatum) are morphologically indistinguishable and thus have been treated as belonging to single species. However, the wasps from the host …

Investigating The Prevalence Of An Insecticide Resistance Gene In Culex Mosquito Populations Of Central Illinois, Kylee R. Noel

Masters Theses

The globalization of society has led to the spread of the vectors, mosquitoes, and diseases. Each year millions of people are killed by diseases vectored by mosquitoes. For example, West Nile Virus alone killed over 2,000 people in North America in 2017; 8 of those deaths being in Illinois. Two prominent vectors of West Nile Virus are Culex pipiens and Culex restuans; which are difficult to differentiate based upon morphological features. In this study, mosquitoes collected from two Illinois counties, Coles County and Champaign County, were first identified based upon morphology and this identification was then compared to probe-based …

Plants, Parasites, And Pollinators: The Effects Of Medicinal Pollens On A Common Gut Parasite In Bumble Bees, George Locascio

Masters Theses

Declines in several pollinator species are due to a variety of factors, including pathogens. Incorporating pollinator-friendly plant species into wild and agricultural habitats could reduce the stress of pathogens if food sources act medicinally against pathogens. Previous research demonstrated one domesticated sunflower cultivar (Helianthus annuus) can dramatically reduce a gut pathogen (Crithidia bombi) of the common eastern bumble bee, Bombus impatiens. To ascertain the breadth of this medicinal trait, we tested whether pollen from several H. annuus cultivars and four relatives could also reduce C. bombi infections in B. impatiens. We also investigated whether …

Surveillance Of Ticks Parasitizing Tennessee Beef Cattle And Investigations Into The Microbial Communities Of Cattle Associated And Questing Amblyomma Maculatum, David Paul Theuret

Masters Theses

Despite the risks that ticks and tick-borne disease pose to the beef cattle industry, many Tennessee producers are unaware of the dangers they represent. This mindset could facilitate the invasion and establishment of exotic ticks and pathogens that would devastate the cattle industry. Current control practices rely on chemical methods, which are not effective long-term; therefore, investigations into creating an integrated approach to control would create more sustainable methods. This study aims to address this through two objectives: The first is to determine the species composition, seasonal prevalence, geographic distribution and diversity of ticks on Tennessee cattle. The second is …

Factors Influencing Impact Of Biological Control Agents Of The Emerald Ash Borer, Theresa Murphy

Masters Theses

Agrilus planipennis, the emerald ash borer (EAB), is a destructive invasive forest pest decimating North American ash trees. Population-wide management of EAB focuses on biological control, with the introduction of four parasitic wasps; one egg parasitoid, Oobius agrili and three larval parasitoids- Spathius galinae, Spathius agrili and Tetrastichus planipennisi. This thesis examines some of the factors influencing the establishment of these larval biocontrol agents. Chapter 1 examines the relationship between woodpeckers and the parasitoids S. agrili and T. planipennisi. Both woodpeckers and these parasitoids attack the larval stage of EAB, which means their impacts overlap and …

Rapid Molecular Detection And Population Genetics Of Pityophthorus Juglandis, A Vector Of Thousand Cankers Disease In Juglans Spp., Emel Oren

Masters Theses

Thousand Cankers Disease (TCD) is a disease complex involving the fungal pathogen Geosmithia morbida, an insect vector Pityophthorus juglandis, and the hosts, Juglans spp. and Pterocarya spp. Signs and symptoms of TCD include crown thinning due to branch dieback, yellowing and wilting of the leaves, appearance of epicormic shoots, numerous entrance/exit holes, gallery formation by P. juglandis, and the development of small, dark brown cankers underneath the bark. TCD originally described from western U.S., has now expanded to eastern U.S. and northwestern Italy. The disease complex is often difficult to diagnose due to the absence of symptoms …

Evaluation Of Total Mercury And Methylmercury Concentrations Of Terrestrial Invertebrates Along Lower East Fork Poplar Creek In Oak Ridge, Tennessee, Chelsea Lynden Standish

Masters Theses

Mercury (Hg) and methylmercury (MeHg) are environmental concerns due to their abilities to cause neurological, reproductive, and other physical damage to wildlife. Lower East Fork Poplar Creek (LEFPC), stemming from the Y-12 National Security Complex, located in Oak Ridge, TN, has elevated concentrations of inorganic mercury, a majority of which was released between 1950 and 1963. This inorganic mercury has been, and is currently, converted to methylmercury. An ecological assessment in 2011 revealed high concentrations of methylmercury in riparian spiders along LEFPC. These results suggested the transfer of mercury from aquatic to terrestrial systems may be higher than previously expected …

Improving Aedes Mosquito Surveillance And La Crosse Virus Screening In Eastern Tennessee, Cassandra Urquhart

Masters Theses

La Crosse virus (LACV), transmitted by infected Aedes triseriatus, Ae. albopictus, and Ae. japonicus mosquitoes is the leading cause of pediatric arboviral encephalitis. Severe cases of LAC encephalitis occur in individuals 16-years-old or younger and may cause permanent neurological damage or fatality. No vaccines exist making mosquito control and disease prevention crucial to public health. Effective screening and surveillance practices are key components to these goals. While a number of standard mosquito surveillance methods exist, continuous testing and improved understanding of vector biology to determine the best ways to implement these methods is important. Additionally, the current standard …

Soil-Water Transport Of A Seed Coated Neonicotinoid Pesticide In Soybean/Maize Cultivation Systems, Geoffrey Nathaniel Duesterbeck

Masters Theses

The current decline of the honey bee (Apis mellifera L.) and other beneficial pollinator species is well documented. Several causes have been cited in this decline including: pathogens, pests, nutrition, and pesticide exposure. Since the advent of the neonicotinoid family of pesticides in the 1990’s an increase in honey bee colony loss has been observed. Neonicotinoid pesticides are commonly applied as a seed treatment to cotton, soybean and maize row crops. As the seed germinates, it absorbs the pesticide from the coating then spreads systemically throughout the entire plant. However, a large portion of the seed coating may stay …

An Ecological Study Of The Kudzu Bug In East Tennessee: Life History, Seasonality, And Phenology, Kadie Elizabeth Britt

Masters Theses

The kudzu bug, Megacopta cribraria (Hemiptera: Plataspidae), an invasive species from Asia, was first discovered in the United States in 2009 in Georgia. It has since spread to other states, including Tennessee, where it has spread rapidly to numerous counties in four years. Its common name, kudzu bug, implies a potential benefit to management of the invasive species kudzu; unfortunately, the kudzu bug has shown little impact on reducing growth of kudzu. The kudzu bug causes agricultural, urban, and health-related concerns in the United States. Soybean losses by kudzu bug have exceeded 20% in some areas of the southeastern United …

Effectiveness Of Entomopathogenic Nematode-Induced Systemic Resistance Against Pests And Pathogens Of Tobacco And Soybeans In Tennessee, Julia Grace Ferguson

Masters Theses

Entomopathogenic nematodes (EPNs) Steinernema and Heterorhabditis are currently used as biological control agents in multiple cropping systems. EPNs also have been shown to induce resistance in some treated plant species, such as tomatoes and hostas. Recent studies where EPNs are applied to the soil have shown reduction in the number of plant parasitic nematodes and foliar nematodes. Other studies have also shown reduction in development of above-ground chewing and sucking insect pests as well as a pathogen. However, the mechanisms that cause these reductions are poorly understood. This research hypothesized that EPNs could induce resistance in tobacco and soybean plants. …