Life Sciences Commons^™

Impact Of Oxytocin And Tetrahydrocannabinol On Signs Of Fear In The Rat, Jair E. Alvarez Jr.

EWU Masters Thesis Collection

BACKGROUND: Oxytocin (OXT) has been used as a post-treatment for post-traumatic stress disorder (PTSD). Previous research suggests that pre-treatment of intranasal OXT attenuates signs of fear in rats; however, the impact of intraperitoneal (i.p) OXT pre-treatment on signs of fear in rats is unknown. We also explored the effects of delta-9 (psychoactive component of cannabidiol) and delta-8 (delta-9 isomer) THC pre-treatment on attenuating signs of fear in the rat. METHODS: For each experiment, male Sprague-Dawley rats were divided into 5 groups, (n=8 per group); 1.) controls (vehicle and no foot shock), 2.) shock (vehicle and foot shock), 3.) low dose …

The Sources And Fates Of Nutrients In The Deep Lake Watershed, Kiler Austin Kenison

EWU Masters Thesis Collection

This water quality survey determined the sources and fates of nutrients within the Deep Lake watershed located in Stevens County, WA. Deep Lake is a 191-acre exorheic lake found just below the Canadian border in northeast Washington state. It is situated at the bottom of a narrow valley with steep walls and is fed throughout the year by snowmelt from tributaries descending the mountains surrounding it. Above and to the north of the lake, the tributaries are utilized by cattle ranchers as a water source for livestock while a small community of homes surrounds the lake. Water samples, discharge, and …

Sialylation As A Mechanism For Preferential Ligand Binding In Cfs1r, Eric J. Beaulaurier

EWU Masters Thesis Collection

Macrophages are immune cells that help provide the first line of defense against a wide range of internal and external insults and create the bridge between innate and adaptive immune responses. When macrophage homeostasis is disrupted, disease states occur. Associated disease states include rheumatoid arthritis, Alzheimer’s disease, and multiple sclerosis. The survival and proliferation of macrophages is largely controlled by signaling through colony stimulating factor 1 receptor (CSF1R). Notably, this receptor can be activated by two non-homologous ligands, colony stimulating factor 1 (CSF1) and interleukin- 34 (IL-34). These two ligands are differentially required for macrophage homeostasis across body systems and …

Investigating The Relationships Between Biotic And Abiotic Factors Affecting Migratory Behavior In Westslope Cutthroat Trout Within The Priest River System, Kyle M. Keenan

EWU Masters Thesis Collection

Numerous salmonid species demonstrate diverse life histories, encompassing both resident and migratory behaviors. Migratory life histories play a pivotal role in maintaining metapopulations for various reasons, facilitating genetic exchange between populations and yielding larger-sized females with increased fecundity relative to residents. This study took place in northern Idaho, within the lower Priest River system, which is highly susceptible to degrading habitat. Previous research has discovered this system as a significant contributor to migratory Westslope Cutthroat Trout (Oncorhynchus lewisi, WCT) in the Lake Pend Oreille and Priest River systems. Expanding on these results, we compared four Priest River tributaries that produced …

Tetrodotoxin, Fungal Pathogen Infection, And Bacterial Microbiome Associations Are Variable In The Skin Microecosystems Of Two Taricha Newt Species, Talon B. Jost

EWU Masters Thesis Collection

Chytridiomycosis is an amphibian disease linked to population declines and species extinctions, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). While chytridiomycosis can result in host death, some amphibians are less susceptible to severe infections through intrinsic factors including host-associated skin microbes aiding defense through resource competition and antifungal metabolite production. Amphibians can also release toxins in response to stress cues to defend against disease, parasitism, and predation. Tetrodotoxin (TTX) is a potent low molecular weight neurotoxin found in genus Taricha, and despite a previously observed negative relationship between differential levels of TTX concentration and Bd infection presence within a …

Revegetation Of Two Drained Reservoirs On The Elwha River Ten Years After Dam Removal, Michael Trier

EWU Masters Thesis Collection

The Elwha and Glines Canyon dams on the Elwha River, Washington, USA were removed between 2011 and 2014 after being in place for a century, and at the time were the largest dams ever removed. The resulting dewatering of Lake Aldwell, the reservoir of the Elwha dam, and Lake Mills, the reservoir of the Glines Canyon dam exposed over 270 hectares of land that had been submerged. While several studies have examined the revegetation of these drained reservoirs, none have gone beyond 5 years since dam removal. These studies found that sediment grain size and reservoir landform (valley walls, terraces …

Synthesis Of Dihydro-Β-Carbolines By Tandem C-H Activation And Aza-Michael Reaction In The Presence Of Rh(Ii)/Squaramide Catalysis: Investigation Of The Mechanism Via Computational Methods, Syed Wasiuddin

Senior Honors Theses and Projects

N-heterocycles are the major component of various bioactive natural products, pharmaceuticals, and their precursors. In particularly, β-carbolines are examples of substituted indole and its derivatives that serve as the basic structures of diverse, therapeutically important molecules with broad pharmacological properties. Rajasekar and Anbarasan have suggested a novel one-pot synthesis for dihydro-β-carbolines involving more than one catalytic system: a rhodium acetate dimer for C-H insertion on the indole and a basic organo-catalyst for the subsequent aza-Michael addition. The product can be obtained enantioselectively by using a chiral squaramide as the organo-catalyst. Since the mechanism of this reaction, including the rate determining …

Quantum Dot Effect On Endocytic Pathways And Eisosome Organization, Onyinye Dorathy Okafor

Graduate Theses/Dissertations

Despite the promising applications of Quantum Dots (QDs) in the biomedical field, the long-lasting effects of QDs on the cell remain poorly understood. To comprehend the mechanisms underlying the toxic effects of QDs in yeast, I characterized defects associated with receptor-mediated endocytosis (RME) as well as on pinocytosis using Saccharomyces cerevisiae as a model in the presence of CdSe/ZnS QDs. My findings revealed that QDs led to an inefficient RME at the early, intermediate, and late stage of endocytic patch maturation at the endocytic site, with the prolonged lifespan of GFP-fused yeast fimbrin (Sac6-GFP), a late marker of endocytosis. The …

The Effect Of Body Size On Mate Choice By Ambystoma Laterale Breeding With Unisexual Salamanders, Cole Christian Duvall

Senior Honors Theses and Projects

Within the genus Ambystoma exists a complex of unisexual (all female) polyploid salamanders, which can breed with males of five sexual species of salamander. Unisexuals face intense sexual selection from diploid males, who prefer to mate with females of their own species. At the Edwin S. George Reserve (ESGR), it has been observed that LLJ unisexuals with large body sizes migrate to breeding ponds earlier than small unisexuals. A possible explanation for this behavior is that large LLJ unisexuals are sexually selected against, when compared to small unisexuals. We hypothesized that A. laterale males would prefer smaller LLJ unisexuals, when …

Sensitivity To Artificial Light And Sound In Bats Using Urban Landscapes, Aleana R. Savage

Graduate Theses/Dissertations

Anthropogenic activity has prompted range shifts, extirpations, and behavioral change of native wildlife. Although humans have long altered the landscape, recent (post-1950s) increases in land use intensification has significantly impacted wildlife habitat and biodiversity. As anthropogenic developments and disturbances compromise habitat, some species have begun to exploit urban areas. While there are some commonalities among synurbic species, such as generalist diets and high fecundity, not all urban wildlife share these characteristics. As urban areas expand, it will be essential to distinguish what drives unique species to select for urban habitat. The gray bat, Myotis grisescens, is an endangered species …

Temporal Distribution Of Potential Waterborne Pathogens In Sequiota Spring, William J. Durstock

Graduate Theses/Dissertations

Waterborne pathogens from human fecal matter pose a significant health risk in karst environments, where domestic wastewater can easily be transferred to the shallow groundwater system via old, leaky septic tanks and damaged sewer lines. This study monitored fecal indicator bacteria (FIB) and potential pathogens in Sequiota Spring located in the karst region of southwest Missouri, using Microbial Source Tracking (MST) and Illumina DNA sequencing of bacterial 16S rRNA genes. MST identified high levels of human fecal indicator bacteria (HFIB) (up to 110,000 cells/L) in July 2020. By June 2022, HFIB levels had dropped significantly (55-fold reduction) after the City …

Patterns Of Epiphytic Bacterial Growth On Flower Surfaces: Relationships With Flower Longevity And Environmental Factors, Rita Nkem Afagwu

Graduate Theses/Dissertations

Flowers host diverse communities of epiphytic bacteria, which can impact floral functions, pollinator interactions, and overall plant fitness. However, little is known about how the abundance of these bacteria change as flowers age, and how these shifts may correlate with floral longevity. In this study I investigate the change in bacterial abundance across the lifespan of a flower from anthesis (opening of bud to flower) to senescence (wilting of flower) and to explore the potential implications for floral longevity. We tracked the age of the flowers by determining the average age to senescence in flowers of 8 plant species over …

Demographics And Recruitment Patterns In A Reintroduced Population Of Alligator Snapping Turtles (Macrochelys Temminckii), Melisa P. Blasky

Graduate Theses/Dissertations

Reintroductions have increasingly become a useful tool for managing wildlife populations, but post-reintroduction studies to evaluate the success of these efforts are often lacking. In 2007, 265 Alligator Snapping Turtles (Macrochelys temminckii) were released into several semi-impounded wetlands in the Washita River drainage basin in southeastern Oklahoma, where surveys in the late 1990s suggested that the species was functionally extirpated. I conducted turtle trapping surveys using baited hoop nets to assess demographics and recruitment patterns in the population 11–12 years after the initial reintroduction. I estimated the age of juveniles by counting scute annuli and compared the data …

Upa-Mediated Polyamidoamine Dendrimer-Based Targeted Gene Delivery System On Triple-Negative Breast Cancer, Hsin-Yin Chuang

Masters Theses

"Around 15% of breast cancers are triple-negative breast cancer (TNBC), which is characterized by the absence of three common receptors—ER, PR, and HER2, and therefore do not respond to hormonal or anti-HER2 therapies. It is urgent to explore targeted therapeutic strategies for TNBC due to its poor prognosis and rare effective targeted therapy. In this study, we developed a polyamidoamine (PAMAM) dendrimer-based targeted gene delivery system—GDP-uPA, to utilize urokinase-type plasminogen activator (uPA) to target uPA receptor (uPAR), which is highly expressed in both TNBC cells and cancer-associated stromal cells. Our results of 1H NMR spectrum, TEM imaging, and MTT assay …

Environmental Health And Impact Of Workload On Errors For Wildland Fire Personnel, Michael Bryan Held

Masters Theses

"This thesis offers an analysis of how environmental health and workload affect wildland fire dispatchers and firefighters, combining results from two studies. The first study, "Environmental Health of Wildland Firefighters: A Scoping Review," performs a scoping review of scientific literature that examines the unique environmental health challenges wildland firefighters face. The review points out the increased risks to safety, health, and well-being from more exposure to natural hazards, identifying key research gaps and priorities. It stresses the need to broaden the geographic and demographic scope of studies, improve analytical methods, and increase research funding and focus for wildland firefighters.

The …

Metal-Ion Doped Borate Bioactive Glasses- A Novel Direction In Minimizing Nosocomial Infections And Antibiotic Resistance, Sarah Fakher

Masters Theses

"Nosocomial infections represent a formidable challenge and induce a substantial burden on patients and healthcare systems. These infections result from the interaction of numerous pathogenic microorganisms, particularly bacteria, and lead to increased morbidity, mortality, and healthcare costs. Extensive research has been carried out to devise innovative solutions, mainly focusing on antimicrobial natural and synthetic substances. However, the proclivity of bacterial strains to form biofilms complicates treatment and elevates antibiotic resistance, prompting research into pioneering more effective and versatile antibacterial strategies. Borate bioactive glasses (BBGs) are the latest, remarkable classes of biomaterials with a wide array of medical applications, owing to …

Differential Conservation And Loss Of Chicken Repeat 1 (Cr1) Retrotransposons In Squamates Reveal Lineage-Specific Genome Dynamics Across Reptiles, Simone M. Gable, Nicholas A. Bushroe, Jasmine M. Mendez, Adam Wilson, Brendan J. Pinto, Tony Gamble, Marc Tollis

Biological Sciences Faculty Research and Publications

Transposable elements (TEs) are repetitive DNA sequences which create mutations and generate genetic diversity across the tree of life. In amniote vertebrates, TEs have been mainly studied in mammals and birds, whose genomes generally display low TE diversity. Squamates (Order Squamata; including ∼11,000 extant species of lizards and snakes) show as much variation in TE abundance and activity as they do in species and phenotypes. Despite this high TE activity, squamate genomes are remarkably uniform in size. We hypothesize that novel, lineage-specific genome dynamics have evolved over the course of squamate evolution. To understand the interplay between TEs and host …

It’S A Trap?! Escape From An Ancient, Ancestral Sex Chromosome System And Implication Of Foxl2 As The Putative Primary Sex-Determining Gene In A Lizard (Anguimorpha; Shinisauridae), Brendan J. Pinto, Stuart V. Nielsen, Kathryn A. Sullivan, Ashmika Behere, Shannon E. Keating, Mona Van Schingen-Khan, Truong Q. Nguyen, Thomas Ziegler, Jennifer Pramuk, Melissa A. Wilson, Tony Gamble

Biological Sciences Faculty Research and Publications

Although sex determination is ubiquitous in vertebrates, mechanisms of sex determination vary from environmentally to genetically influenced. In vertebrates, genetic sex determination is typically accomplished with sex chromosomes. Groups like mammals maintain conserved sex chromosome systems, while sex chromosomes in most vertebrate clades are not conserved across similar evolutionary timescales. One group inferred to have an evolutionarily stable mode of sex determination is Anguimorpha, a clade of charismatic taxa including monitor lizards, Gila monsters, and crocodile lizards. The common ancestor of extant anguimorphs possessed a ZW system that has been retained across the clade. However, the sex chromosome system in …

A “War” Over Lobster And Whales: The Issue-Attention Cycle, Media Discourse, And Political Ecology Of Right Whale Science And Conservation In Six Us Newspapers, Marcus Reamer, Catherine Macdonald, Julia Wester, Russell Fielding, Meryl Shriver-Rice

Honors College Faculty Publications

News organizations and journalists are important and influential actors in environmental politics. Their reporting on social and environmental issues often follows issue-attention cycles (IACs) that emphasize drama and problematization to maintain public interest. This study examined nearly 13 years of news coverage to understand the media discourse about the Critically Endangered North Atlantic right whale (NARW) and its conservation. Content analysis and critical discourse analysis were used to analyze 356 texts published in six large US newspapers between January 1, 2010 and March 15, 2023. NARW conservation and management received increased public attention and an IAC began in 2017 after …

Non-Target Site Mechanisms Of Cross-Resistance Evolution To Florpyrauxifen-Benzyl In 2,4-D-Resistant Palmer Amaranth (Amaranthus Palmeri), Jeong-In Hwang, Jason K. Norsworthy, L. Tom Barber, Thomas R. Butts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

The evolution of herbicide resistance in weeds can reduce the herbicide’s efficacy, depleting crop yield and quality. Our group previously confirmed 2,4-D resistance in three Palmer amaranth (Amaranthus palmeri S. Watson) populations (R1 to R3). In the current study, the first filial (F₁) seeds of 2,4-D–resistant populations were subjected to screening tests for resistance to other auxin-mimicking herbicides, florpyrauxifen-benzyl (FPB; 30 g ai ha⁻¹) and dicamba (560 g ae ha⁻¹). Dicamba killed all resistant populations. FPB provided 100% control of only the R3 population. Sensitivities to FPB were reduced by 2 and 35 percentage …

Association Of Plasma Neurofilament Light Chain With Microstructural White Matter Changes In Down Syndrome, Herminia Diana Rosas, Nathaniel David Mercaldo, Yasemin Hasimoglu, Melissa Petersen, Lydia R. Lewis, Florence Lai, David Powell, Asim Dhungana, Ali Demir, David Keater, Michael Yassa, Adam M. Brickman, Sid O'Bryant

Neuroscience Faculty Publications

INTRODUCTION: Both micro- and macrostructural white matter (WM) abnormalities, particularly those related to axonal degeneration, are associated with cognitive decline in adults with Down syndrome (DS) prior to a diagnosis of Alzheimer disease. Neurofilament light chain (NfL) is a support protein within myelinated axons released into blood following axonal damage. In this study we investigated cross-sectional relationships between WM microstructural changes as measured by diffusion tensor imaging (DTI) and plasma NfL concentration in adults with DS without dementia.

METHODS: Thirty cognitively stable (CS) adults with DS underwent diffusion-weighted MRI scanning and plasma NfL measurement. DTI measures of select WM tracts …

The Differential Proteomic Response To Ischemic Stroke In Appalachian Subjects Treated With Mechanical Thrombectomy, Christopher J. Mclouth, Benton Maglinger, Jacqueline A. Frank, Kristin J. Hazelwood, Jordan P. Harp, Will Cranford, Shivani Pahwa, David Dornbos Iii, Amanda L. Trout, Ann M. Stowe, Justin F. Fraser, Keith R. Pennypacker

Neurology Faculty Publications

Introduction The Appalachia region of North America is known to have significant health disparities, specifically, worse risk factors and outcomes for stroke. Appalachians are more likely to have comorbidities related to stroke, such as diabetes, obesity, and tobacco use, and are often less likely to have stroke interventions, such as mechanical thrombectomy (MT), for emergent large vessel occlusion (ELVO). As our Comprehensive Stroke Center directly serves stroke subjects from both Appalachian and non-Appalachian areas, inflammatory proteomic biomarkers were identified associated with stroke outcomes specific to subjects residing in Appalachia. Methods There were 81 subjects that met inclusion criteria for this …

Adgrl1 Is A Glucose Receptor Involved In Mediating Energy And Glucose Homeostasis, Kavaljit H Chhabra, Siresha Bathina, Tumininu S Faniyan, Dennis J Samuel, Muhammad Ummear Raza, Leticia Maria De Souza Cordeiro, Gonzalo Viana Di Prisco, Brady K Atwood, Jorge Robles, Lauren Bainbridge, Autumn Davis

Pharmacology and Nutritional Sciences Faculty Publications

AIMS/HYPOTHESIS: The brain is a major consumer of glucose as an energy source and regulates systemic glucose as well as energy balance. Although glucose transporters such as GLUT2 and sodium-glucose cotransporter 2 (SGLT2) are known to regulate glucose homeostasis and metabolism, the identity of a receptor that binds glucose to activate glucose signalling pathways in the brain is unknown. In this study, we aimed to discover a glucose receptor in the mouse hypothalamus.

METHODS: Here we used a high molecular mass glucose-biotin polymer to enrich glucose-bound mouse hypothalamic neurons through cell-based affinity chromatography. We then subjected the enriched neurons to …

Rare Variant Analyses Validate Known Als Genes In A Multi-Ethnic Population And Identifies Antxr2 As A Candidate In Pls, Tess D. Pottinger, Joshua E. Motelow, Gundula Povysil, Cristiane A. Martins Moreno, Zhong Ren, Hemali Phatnani, The New York Genome Center Als Sequencing Consortium, Timothy J. Aitman, Javier Santoyo‑Lopez, Scottish Genomes Partnership, Hiroshi Mitsumoto, Als Cosmos Study Group, Pls Cosmos Study Group, Gtac Investigators, David B. Goldstein, Matthew B. Harms

Neurology Faculty Publications

Background Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting over 300,000 people world‑ wide. It is characterized by the progressive decline of the nervous system that leads to the weakening of muscles which impacts physical function. Approximately, 15% of individuals diagnosed with ALS have a known genetic variant that contributes to their disease. As therapies that slow or prevent symptoms continue to develop, such as antisense oligonucleotides, it is important to discover novel genes that could be targets for treatment. Additionally, as cohorts continue to grow, performing analyses in ALS subtypes, such as primary lateral sclerosis (PLS), becomes possible …

Relationships Between Cliff Swallows (Petrochelidon Pyrrhonota) And Feather Coloration, Morphological Characteristics, And Colony Size, Sonja M. Brandt

Master's Theses or Doctor of Nursing Practice

Environmental stressors such as drought and roadways can strongly affect breeding birds. Cliff Swallows (Petrochelidon Pyrrhonota) are aerial insectivores that experience mortality from car collisions, because they often nest and hunt under bridges and road culverts. Individual traits that may convey social information, such as body condition, or feather coloration, might be associated with better coping around cars and other environmental stressors. Few studies have investigated relationships between coloration and other environmental stressors, such as water loss due to drought near the colony and foraging areas. Colony size can be heavily affected by various environmental factors such as water level …

The Physiological And Behavioral Effects Of A Centrally Administered Oxytocin Receptor Antagonist On Maternal Buffering In Infant Guinea Pigs, Kendra A. Carter

Browse all Theses and Dissertations

This study investigates the role of endogenous oxytocin (OT) in maternal buffering of infant stress responses in guinea pigs. Infants received intracerebroventricular infusion of an oxytocin receptor antagonist (OTA) or artificial cerebrospinal fluid (aCSF) immediately before being placed with the mother in a novel environment for 60 minutes. Blood cortisol levels and behavioral responses, including vocalizations and crouching, were measured throughout the testing period. Results indicate only a significant effect of time, with cortisol levels increasing with time spent in the novel environment. Otherwise, no significant differences were observed either physiologically or behaviorally between aCSF and OTA conditions. This study …

Detecting Cognitive Decline In High-Functioning Older Adults: The Relationship Between Subjective Cognitive Concerns, Frequency Of High Neuropsychological Test Scores, And The Frontoparietal Control Network, Justin E. Karr, Jonathan G. Hakun, Daniel B. Elbich, Cristina N. Pinheiro, Frederick A. Schmitt

Neurology Faculty Publications

Objective: Neuropsychologists have difficulty detecting cognitive decline in high-functioning older adults because greater neurological change must occur before cognitive performances are low enough to indicate decline or impairment. For high-functioning older adults, early neurological changes may correspond with subjective cognitive concerns and an absence of high scores. This study compared high- functioning older adults with and without subjective cognitive concerns, hypothesizing those with cognitive concerns would have fewer high scores on neuropsychological testing and lower frontoparietal network volume, thickness, and connectivity.

Method: Participants had high estimated premorbid functioning (e.g., estimated intelligence ≥75th percentile or college-educated) and were divided based on …

Impact Of Amyloid And Cardiometabolic Risk Factors On Prognostic Capacity Of Plasma Neurofilament Light Chain For Neurodegeneration, Keun You Kim, Eosu Kim, Jun-Young Lee, Alzheimer’S Disease Neuroimaging Initiative

Neurology Faculty Publications

Background Plasma neurofilament light chain (NfL) is a blood biomarker of neurodegeneration, including Alzheimer’s disease. However, its usefulness may be influenced by common conditions in older adults, including amyloid‑β (Aβ) deposition and cardiometabolic risk factors like hypertension, diabetes mellitus (DM), impaired kidney function, and obesity. This longitudinal observational study using the Alzheimer’s Disease Neuroimaging Initiative cohort investigated how these conditions influence the prognostic capacity of plasma NfL. Methods Non‑demented participants (cognitively unimpaired or mild cognitive impairment) underwent repeated assessments including the Alzheimer’s Disease Assessment Scale‑Cognitive subscale (ADAS‑Cog) scores, hippocampal volumes, and white matter hyperintensity (WMH) volumes at 6‑ or 12‑month …

Astrocytic Stress Response Is Induced By Exposure To Astrocyte-Binding Antibodies Expressed By Plasmablasts From Pediatric Patients With Acute Transverse Myelitis, Chad Smith, Kiel M. Telesford, Sara G. M. Piccirillo, Yamhilette Licon‑Munoz, Wei Zhang, Key M. Tse, Jacqueline R. Rivas, Chaitanya Joshi, Dilan S. Shah, Angela X. Wu, Ritu Trivedi, Scott Christley, Yu Qian, Lindsay G. Cowell, Richard H. Scheuermann, Ann M. Stowe, Linda Nguyen, Benjamin M. Greenberg, Nancy L. Monson

Neurology Faculty Publications

Background Pediatric acute transverse myelitis (ATM) accounts for 20–30% of children presenting with a first acquired demyelinating syndrome (ADS) and may be the first clinical presentation of a relapsing ADS such as multiple sclerosis (MS). B cells have been strongly implicated in the pathogenesis of adult MS. However, little is known about B cells in pediatric MS, and even less so in pediatric ATM. Our lab previously showed that plasmablasts (PB), the earliest B cell subtype producing antibody, are expanded in adult ATM, and that these PBs produce self‑reactive antibodies that target neurons. The goal of this study was to …

A Case Of One Step Forward And Two Steps Back? An Examination Of Herbicide-Resistant Weed Management Using A Simple Agroecosystem Dynamics Model, Srinadh Kodali, Chris Flores-Lopez, Isabelle Lobdell, Branson Kim, James C. Russell, Lane Michna, Benjamin L. Turner

Mechanical & Aerospace Engineering Faculty Publications

Global herbicide-resistant weed populations continue rising due to selection pressures exerted by herbicides. Despite this, herbicides continue to be farmers’ preferred weed-control method due to cost and efficiency relative to physical or biological methods. However, weeds developing resistance to herbicides not only challenges crop production but also threatens ecosystem services by disrupting biodiversity, reducing soil health, and impacting water quality. Our objective was to develop a simulation model that captures the feedback between weed population dynamics, agricultural management, profitability, and farmer decision-making processes that interact in unique ways to reinforce herbicide resistance in weeds. After calibration to observed data and …