Entomology Commons^™

A Transcriptomic Exploration Of Hawaiian Drosophilid Development And Evolution, Madeline M. Chenevert

University of New Orleans Theses and Dissertations

One in four known species of fruit flies inhabit the Hawaiian Islands. From a small number of colonizing flies, a wide range of species evolved, some of which managed to reverse-colonize other continental environments. In order to explore the developmental pathways, which separate the Hawaiian Drosophila proper and the Scaptomyza group that contains reverse-colonized species, the transcriptomes of two better-known species in each group, Scaptomyza anomala and Drosophila grimshawi, were analyzed to find changes in gene expression between the two groups. This study describes a novel transcriptome for S. anomala studies as well as unusual changes in gene expression …

The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga

Electronic Theses and Dissertations

Dickeya dianthicola (Samson) causing blackleg and soft rot was first detected in potatoes grown in Maine in 2014. Previous work has suggested that insects, particularly aphids, may be able to vector bacteria in this genus between plants, but no conclusive work has been done to confirm this theory. In order to determine whether insect-mediated transmission is likely to occur in potato fields, two model potato pests common in Maine were used: the Colorado potato beetle (Leptinotarsa decimlineata Say) and the green peach aphids (Myzus persicae Sulzer). Olfactometry and recruitment experiments evaluated if either insect discriminates between infected and …

Mosquito Diversity And Positive Pools For The West Nile Virus In Forested Versus Non-Forested Areas, Elizabeth C. Paul

Honors Projects

The West Nile virus (WNV) is one of the leading causes of mosquito borne illness in the United States (CDC, 2018). This virus is a neurotropic pathogen that can cause fever and encephalitis. It is known that the Culex species is the primary vector for WNV. Humans infected with the WNV are typically asymptomatic. There is a small portion of individuals that experience West Nile fever which could include symptoms like high fever, vision loss, and coma (CDC, 2018). Previous studies have shown that mosquitoes tend to favor forests and wetlands (Hay et al., 1998), however, it is unknown if …

Spatial And Temporal Variation In The Aquatic Invertebrate Community Structure Of Rock Pools Along The Penobscot River, Maine, Chase R. Gagne

Electronic Theses and Dissertations

Pools of water that form in the fissures and depressions of rock outcrops, known as rock pools, are fairly common aquatic habitats that can easily be found along the rocky banks of many of Maine’s major rivers. In general, rock pools and the aquatic invertebrates inhabiting them have received little research attention and, though ubiquitous, have never been studied in Maine. My research addressed this knowledge gap by surveying 40 rock pools at four sites along the Penobscot River in Maine. The rock pools themselves had highly variable environmental characteristics and differed across sites and over time, especially in hydroperiod. …

Influence Of The Annual Flood Pulse Of The Atchafalaya River And Updates On The Ecology Of Floodplain Aquatic And Semi-Aquatic Hemiptera And Their Associates, Patricia Ls Wooden

LSU Master's Theses

Understanding the biodiversity of insects in an area provides key insights into the health and uniqueness of an ecosystem. Here we increase the breadth of knowledge of Louisiana aquatic Hemiptera through field and natural history collection research. The Atchafalaya River floodplain is variably inundated throughout the course of the year, peaking with the spring flood pulse, resulting in spatiotemporally dynamic habitats for aquatic organisms. Buffalo Cove Water Management Unit (BC) is within the river system, whereas Lake Fausse Pointe (LFP) has been leveed from the influence of the river for over 50 years. We collected aquatic macroinvertebrates with quatrefoil light …

The Evolution Of Spinosad Resistance In Colorado Potato Beetles (Leptinotarsa Decemlineata), Coby Michael Klein

Dissertations, Theses, and Capstone Projects

Colorado potato beetles (Leptinotarsa decemlineata) are a major pest of cultivated potato plants worldwide. They are well-known for their ability to rapidly evolve resistance to all major classes of pesticides. Defoliation of potato plants by L. decemlineata can reduce potato yields by a considerable margin. The damage done by resistant beetles is steep and much research is focused on developing new chemical controls, especially those derived from naturally occurring compounds. Spinosad is a relatively new natural product insecticide, introduced approximately a decade ago, suitable for use in organic farming. Potato beetles on Long Island, NY developed very strong …

The Relative Importance Of Larval And Adult Nutrition In The Isotopic Profile Of The Spermatophore Produced By The Male True Armyworm Moth (Mythimna Unipuncta) (Haworth)., Aida Parvizi

Electronic Thesis and Dissertation Repository

The wings of true armyworm (Mythimna unipuncta) are metabolically inactive tissue and as their isotopic profiles are determined by resources obtained during larval development, they provide information on natal origin of immigrants. The majority of female immigrants are mated so could the isotopic profiles of spermatophores dissected from her reproductive tract provide information about the natal origin of her mates? However, as spermatophores are produced by metabolically active male accessory glands and could use resources obtained from larval and adult feeding I conducted experiments to determine the relative importance of these two dietary sources on the isotopic profiles …

Seed Predation By Owyhee Harvester Ants And The Potential Of Seed Introductions In Recovery Efforts For Slickspot Peppergrass, Jennifer A. Brown

Boise State University Theses and Dissertations

Slickspot peppergrass (Lepidium papilliferum) is a rare plant endemic to the sagebrush-steppe habitat in southwestern Idaho. Within sagebrush-steppe, the plant is restricted to microsites known as “slick spots”– shallow depressions of soil characterized by distinct clay layers and surface water retention that is higher than that of surrounding areas. Having one of the highest extirpation rates among rare plant taxa in Idaho, and considering its unique habitat requirements, limited range, and declining numbers, land managers and conservationists have voiced concern regarding the species’ long-term viability. While range-wide declines in slickspot peppergrass have been attributed largely to the loss …

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Graduate Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the …

Temperature Influence On Insecticide Resistance In Aedes Aegypti And Aedes Albopictus Mosquitoes From South Texas, Wendy Soledad Salinas

Theses and Dissertations

Aedes aegypti and Aedes albopictus are vectors for several emerging arboviruses including Zika, chikungunya and dengue. Both mosquitoes are found along the Rio Grande River in South Texas, along the border between Mexico and the United States of America. These mosquito species typically reside near human settlements. A preventative measure public health official use to help halt the spread of diseases is by controlling vector population with the use of insecticides, but as temperature vary, and with the constant exposure to commonly used insecticides, mosquitoes from South Texas may be developing a resistance to the insecticides. Resistance to insecticides may …

Determining The Presence Or Absence Of Euscepes Postfasciatus In Haiti And Use Of Molecular Markers For The Distinction Of Cylas Formicarius Elangantulus Biotypes, Marie Rachele Lexidort

LSU Master's Theses

Cylas formicarius elegantulus (Summers) and Euscepes postfaciatus (Fairmaire) are the most destructive sweetpotato weevils in the Caribean Basin. However, damage occurring in sweetpotato production in Haiti is attributed to C. formicarius (S), since it is known to be the most prevalent species while, conflicting information is available pertaining to the occurrence of the E. postfaciatus (F). This study was conducted in the summer of 2018 to determine the presence or absence of E. postfaciatus (F) in Haiti. 98 weevil samples from field (70% ) and infested sweetpotato roots from field and regional markets were collected (30%) in the most relevant …

Assessing The Stability And Distribution Of A Newly Discovered Endangered Bumble Bee Population In Northeastern Illinois, Barbara Locascio

Pence-Boyce STEM Student Scholarship

Many species of bumble bees (Bombus spp.) have been declining in abundance across North America. In the Midwest declines, including that of B. affinis, recently listed as a federally endangered species, are attributed to several factors including habitat loss. Native tallgrass prairies could be ideal areas for Bombus spp. communities to sustain populations, due to native floral resources. However, few studies have been done to determine this. Our objective was to determine the stability and consistency of B. affinis populations at Midewin National Tallgrass Prairie and to investigate whether Goose Lake Prairie, a nearby prairie remnant, …

Effects Of Virus Infection And Volatiles On Aphid Virus Vector Behavior On Sweetpotato, John Lawrence Dryburgh

LSU Doctoral Dissertations

Sweetpotato is affected by a wide variety of viruses worldwide, which can cause yield losses of up to 90%. Many of these viruses are transmitted by aphids in a non-persistent manner. Non-persistent viruses are acquired and transmitted within minutes, and thus conventional control, such as insecticides, are ineffective. Altering aphid movement and feeding behavior may affect the rate of virus transmission. One potential method to alter aphid behavior is volatile organic compounds (VOC), including volatiles emitted by virus infected plants, plant hormones, and commercial control agents. Aphid movement near sweetpotato fields was monitored to determine trends throughout the growing season. …

The Role Of Atp-Sensitive Inward Rectifier Potassium Channels In The Regulation Of Reactive Oxygen Species In The Western Honey Bee, Apis Mellifera L., Christopher J. Fellows

LSU Master's Theses

Colonies of managed honey bees are annually being lost at an unsustainable rate, partly due to reduced immunocompetence that leads to acute viral outbreaks and mortality. To aid in restoring honey bee health despite the myriad of environmental stressors, this thesis focuses on identifying novel physiological pathways that can mitigate virus-mediated mortality through increased immune function. Previous work has demonstrated that a family of potassium ion channels, termed K_ATP channels, mediate the survival of honey bees during infection from a model virus, suggesting K_ATP channels may drive antiviral immunity. Interestingly, these channels have been linked to the regulation …

Using Pseudo Nomarski Contrast To Study Hemocytes Of Galleria Mellonella, Westley David Peterson

MSU Graduate Theses

Differentiation of insect hemocytes requires microscopes equipped with differential interference contrast (DIC), s.c. Nomarski’s contrast. However, the high price of DIC limits speed and efficacy of hemocyte studies. For my thesis, I developed two low cost microscope sets equipped with custom oblique illumination filters. The oblique illumination filters, that I produced, provided high quality images comparable with those produced by DIC, for a fraction of the cost and allowed me to train laboratory personnel quickly. Microscopes with these oblique illumination filters were used in studies of spherulocytes and for rapid screening of plant essential oils to impair insect immune system. …

Recovery Of Domestic Behaviors By A Parasitic Ant (Formica Subintegra) In The Absence Of Its Host (Formica Subsericea), Amber Nichole Hunter

MSU Graduate Theses

Dulosis is a type of social parasitism in which a parasitic ant has become dependent on captured workers (hosts) of a closely related species. Dulosis can be either facultative or obligate depending on the degree of dependence on host workers. As parasites become more specialized over evolutionary time, their domestic abilities degenerate until they become unable to survive without the host. However, the ‘lost’ behaviors may display some degree of recovery when host workers are unavailable to do the tasks. The Formica sanguinea group consists of 12 species of parasitic ants, which are all traditionally considered to be facultative parasites. …

Vertical Connectivity Influences Secondary Production, Community Diversity, And Resilience In An Ozark Stream, Nathan C. Dorff

MSU Graduate Theses

The hyporheic zone, a key component of stream vertical connectivity, supports stream function (e.g., nutrient regeneration) and provides habitat for aquatic biota. The Ozark Highlands ecoregion contains gravel-bed streams that have extensive hyporheic zones and that are subject to recurrent flash floods. I sampled Leuctra tenuis(Pictet) nymphs from the hyporheic habitat (30-45 cm below the streambed) in a gravel-bed reach and an intermittent tributary of an Ozark stream from early instar to adult emergence. Concurrently, I sampled benthic insects in two reaches of the same stream that differed primarily in amount of hyporheic habitat (bedrock vs. gravel) and monitored …

Physiological Characterization Of Inward Rectifier Potassium (Kir) Channels In Insect Neural Systems, Rui Chen

LSU Master's Theses

A complete understanding of the physiological pathways critical for proper function of the insect nervous system is still lacking. The recent development of potent and selective small-molecule modulators of insect inward rectifier potassium channels has enabled the interrogation of the physiological role and toxicological potential of Kir channels within various insect tissue systems. Therefore, we aimed to highlight the physiological and functional role of neural Kir channels in the central nervous system, muscular system, and neuromuscular system through pharmacological and genetic manipulations. Our data provide significant evidence that Drosophila neural systems rely on the inward conductance of K+ ions for …

Landscape Pattern And Wild Bee Communities In Maine, Brianne Du Clos

Electronic Theses and Dissertations

Commercial production of lowbush blueberry (Vaccinium angustifolium Aiton) in Maine relies primarily on managed honeybee hives; however, naturally occurring wild bees are more efficient pollinators of the crop. Wild bees have short foraging distances and must nest near crop fields to provide pollination services. After crop bloom, the surrounding landscape must provide sufficient forage to maintain wild bee populations for the remainder of the growing season. Lowbush blueberries in Maine are produced in a mixed-use landscape with two distinct landscape contexts. Here, we document bee communities and habitat resources (nesting and floral) in power line rights-of-way and eight land …

Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias

Electronic Theses and Dissertations

Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To …

Mesopredator Distribution, Abundance And Potential Competition With The American Burying Beetle (Nicrophorus Americanus) At Fort Chaffee Joint Maneuver Training Center, Karisa Fenton

Theses and Dissertations from 2019

The American burying beetle (Nicrophorus americanus, hereafter ABB) was listed as an endangered species in 1989 and many hypotheses have been developed to explain their rangewide decline. I investigated the carcass competition hypothesis that implicates increased competition between vertebrate scavengers and ABBs for appropriate-sized carcasses as a cause for ABB decline. Predators of medium size that occupy an intermediate trophic level (hereafter mesopredators) are potential competitors for carcasses. I used camera trapping to assess mesopredator abundances in nine different habitats at Fort Chaffee Joint Maneuver Training Center (FCJMTC) in western Arkansas because this area supports the largest known population of …

Reproductive Character Displacement In Calopteryx Aequabilis And C. Maculata: Improving Species Recognition Through The Divergence Of Male Mating Preferences, Melissa Encinias

Masters Theses, 2010-2019

An ongoing evolutionary question is how co-occurring species maintain reproductive barriers when they are morphologically, behaviorally, and ecologically similar. Without geographic isolation, traits involved in species recognition may be under selection to enhance reproductive barriers. Exaggerated trait differences between species in sympatric populations may reflect selection to reduce misdirected mating between species, or reproductive character displacement. While this phenomenon is widely recognized as an important stage in the speciation process, there is little direct evidence of this process in nature. In two North American damselfly species, Calopteryx aequabilis and C. maculata, wing pigmentation is sexually dimorphic and also shows …

Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys

Graduate Theses and Dissertations

A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …

The Impact Of Fall Armyworm, Spodoptera Frugiperda (J.E. Smith), Feeding And Mechanical Defoliation On Growth And Yield Of Rice, Oryza Sativa (L.), Layton Denman Mccullars

Graduate Theses and Dissertations

The fall armyworm, Spodoptera frugiperda (J.E. Smith), (FAW) is a serious pests of many crops, and can be observed feeding throughout the entire growing season on rice, Oryza sativa, (L.). A new defoliation based threshold would help rice growers and consultants make more economically sound decisions for FAW. Work from this thesis focuses on determining the amount of damage caused by FAW feeding at different growth stages and effective insecticide seed treatments for controlling this pest.

Field plots were mechanically defoliated to determine grain yield loss across multiple growth stages and defoliation percentages. Results indicated that defoliation in late vegetative …

Geospatial Analysis Of Rickettsial Species, Amy Frank

Entomology Undergraduate Honors Theses

Rickettsia species are obligate intracellular, arthropod-borne bacteria with a potential to cause multiple diseases including Rocky Mountain spotted fever (RMSF). Fleas, mites, and ticks serve as vectors for Rickettsia, but ticks are the primary vector of interest. RMSF and other rickettsial diseases have continued to gain importance in both human and veterinary medicine as RMSF is the most common tick-borne disease within the United States according to the Lyme and Tick-Borne Disease Research Center. A statewide citizen science project was utilized to determine the prevalence of Spotted Fever Group (SFG) Rickettsia in Arkansas. This project yielded results in 64 …

Do Enallagma Exsulans From Streams And Lakes Show Patterns Of Divergence?, Savannah Rae Graham

Graduate Theses and Dissertations

Divergent selection across heterogenous environments could lead to adaptive divergence in populations resulting in potential local adaption. These populations have phenotypic differences that are fitness related and make native individuals more fit than non-native individuals. My research focuses on a species of damselfly, Enallagma exsulans, to explore local adaptation and morphological differences as a result of divergent selection or plasticity. My first study explored potential local adaptation of wild caught stream and lake E. exsulans using a reciprocal transplant design, a classic approach for this objective. The stream and lake sites chosen were on a small spatial scale allowing for …

Indole Sensitivity In Various Insect Herbivores., Rakhi Patel

College of Arts & Sciences Senior Honors Theses

When plants in nature are attacked by herbivores, they frequently release airborne volatiles. These herbivore-induced plant volatiles (HIPVs) help plants defend themselves against herbivore attack by calling in natural enemies, but HIPVs may also be directly toxic to herbivores. Indole (C₈H₇N) is a common HIPV that is toxic to caterpillars, but its relative toxicity to different caterpillars has not been explored. I tested the toxicity of indole on six caterpillar species (Spodoptera frugiperda, Trichoplusia ni, Spodoptera exigua, Anticarsia gemmatalis, Heliothis virescens, and Helicoverpa zea). Results show that indole is …

Effects Of Polystrene Foam On The Growth And Development Of Darkling Beetles (Tenebrio Molitor), Nick Langlois

Undergraduate Distinction Papers

The growing field of entomoremediation explores the use of insects and other invertebrates as biological agents for the natural removal of hazardous substances, and recent research has investigated the potential for using mealworms (Tenebrio molitor) to digest and decompose polystyrene. Two experiments conducted over two years tested the tolerance of mealworm populations to the inclusion of polystyrene in their diet, and the ability of these diets to support multi-generational populations. The first experiment compared mealworms raised on a diet of 100% polystyrene foam with mealworms raised on a control diet of wheat bran and potatoes. The second experiment …

Effects Of Plant Viruses On Vectors And Non-Vector Herbivores In Three Different Pathosystems, Sunil Paudel

LSU Doctoral Dissertations

Plant viruses are an important component of agro-ecosystems and the knowledge of impacts they can cause on their hosts, and on different vectors and non-vector herbivores associated with the hosts, is very crucial in devising sound management strategies for virus disease and vector control in the landscape. The interactions between these components, however, are difficult to predict and vary according to the system under investigation. In order to understand some of these interrelationships, different sets of experiments were carried out in three different pathosystems to look at the impacts of plant viruses on vector and non-vector herbivores. Firstly, in Sorghum …

Mosquito Image Classification Using Convolutional Neural Networks, Sumanth Vissamsetty

LSU Master's Theses

Human life has always been affected by insects, especially mosquitoes, since it's early beginnings. This pesky insect acts as a vector that transmit pathogens through feeding on our blood, spreading life-threatening diseases like Zika Virus, Malaria, Dengue fever, Chikungunya and more. It is important to prevent these mosquitoes from harming humans and one way to do so is to control the mosquito population, or mosquito abatement as it is commonly known. It is important to note that not all mosquitoes are the same and each of them live, reproduce and attack in their own unique way. Hence it is crucial …