Other Plant Sciences Commons^™

Characterizing Gut Microbial Communities And Symbiont-Mediated Detoxification In Herbivorous Insects, Rachel C. Vargas

Biology Dissertations

Insect gut bacteria are vital contributors to host physiology, yet the broader prevalence and fitness implications of symbiont-mediated detoxification remain poorly understood. This thesis investigates these dynamics across three research chapters. Chapter 1 uses 16S rRNA sequencing to characterize how grasshopper gut microbial communities vary across species, dietary breadths, and gastrointestinal segments. Chapter 2 evaluates the detoxification capacity of over 150 bacterial isolates from diverse herbivores against the plant allelochemicals phenethyl isothiocyanate, rutin, and chlorogenic acid to determine if host dietary specialization predicts microbial metabolic ability. Finally, Chapter 3 employs fitness bioassays to test whether inoculating generalist herbivores with detoxifying …

Optimizing Plant Nutrient Uptake: Cost Function Sensitivity Analysis Of The Fun Model, Gabriel Alpay, Joshua B. Fisher, Renato K. Braghiere, Edward R. Brzostek, Gabriella R. Dauber, Kara Allen, Rosemary A. Fisher

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study explores the cost functions of the Fixation & Uptake of Nutrients (FUN) model, which aims to optimize the amount of carbon used when plants acquire their necessary nutrients from the soil to maximize nitrogen (N) and phosphorus (P) uptake while minimizing the carbon cost. Specifically, we aimed to quantify the sensitivity of FUN outputs to the parameters belonging to the cost of nitrogen and phosphorus uptake functions by arbuscular mycorrhizal and ectomycorrhizal fungi. We present three dimensions of sensitivity analysis: (1) adjusting all parameters at the same time; (2) keeping one parameter constant while varying the other; and, …

Does Green Stem Photosynthesis Affect Plant Drought Tolerance And Recovery In Avocado?, Nadia A. Valverdi, Paula Guzmán-Delgado, Gregory R. Goldsmith, Eleinis Ávila-Lovera

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Woody plants with green stems may have advantages over non-green-stemmed plants in that extra photosynthetic carbon gain has the potential to improve plant drought tolerance and aid drought recovery. However, most studies relating to green stem photosynthesis and drought tolerance have been conducted on non-horticultural plants under natural growing conditions. We investigated whether avocado green stem photosynthesis enhances drought tolerance and recovery. We applied light exclusion and drought treatments to 3-year-old potted trees of cultivars ‘Hass’ and ‘Fuerte’. Measurements of soil moisture, midday stem water potential, stem photosynthesis, bark chlorophyll concentration, concentration of sugars + starch and stem hydraulic conductivity …

Gubic: The Global Urban Biological Invasions Compendium For Plants, Daijiang Li, Luke J. Potgieter, Myla F. J. Aronson, Irena Axmanová, Benjamin Baiser, Marta Carboni, Laura Celesti-Grapow, Sonja Knapp, Ingolf Kühn, Ana Carolina Lacerda De Matos, Zdeňka Lososová, Flavia A. Montaño-Centellas, Petr Pyšek, David M. Richardson, Lauren B. Trotta, Rafael D. Zenni, Sarel S. Cilliers, Bruce D. Clarkson, Amy J. S. Davis, Rebecca W. Dolan, Marcin M. Dyderski, Franz Essl, Orou G. Gaoue, Joanne Gui, Charly Géron, Gustavo Heringer, Cang Hui, Anzar A. Khuroo, Stefan Klotz, Peter M. Kotanen, Holger Kreft, Frank A. Sorte, Jonas J. Lembrechts, Bernd Lenzner, Christopher A. Lepczyk, Scott Macivor, Cristina Martínez-Garza, Akira S. Mori, Charles Nilon, Jan Pergl, Stefan J. Siebert, Alyona S. Tretyakova, Toby P. N. Tsang, Kei Uchida, Mark Van Kleunen, Montserrat Vilà, Hua-Feng Wang, Patrick Weigelt, Peter Werner, Nicholas S. G. Williams, Marten Winter, Marc Cadotte

Scholarship and Professional Work - LAS

Abstract Urban areas are foci for the introduction of non-native plant species, and they often act as launching sites for invasions into the wider environment. Although interest in biological invasions in urban areas is growing rapidly, and the extent and complexity of problems associated with invasions in these systems have increased, data on the composition and numbers of non-native plants in urbanized areas remain scattered and idiosyncratic. We assembled data from multiple sources to create the Global Urban Biological Invasions Compendium (GUBIC) for vascular plants representing 553 urban centres from 61 countries across every continent except Antarctica. The GUBIC repository …

Ms Environmental Biology Capstone: Evaluating Environmental Risks And Conflicts In Golf Course Landscapes, Meredith Boos

Regis University Student Publications (comprehensive collection)

1) This review investigates the relationship between pesticide use on golf courses and in agriculture to determine whether the adverse health effects documented in agricultural settings also apply to golf course environments. While the negative health effects from agricultural pesticide use are well established, golf courses use pesticides with greater frequency and intensity, suggesting a potentially higher exposure risk for both workers and players.

2) This study proposes methods to quantify pesticide bioaccumulation on golf courses and adjacent lands. We hypothesize that areas surrounding golf courses will exhibit a spatial gradient of pesticide accumulation, increasing with proximity to treated sites …

Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez

Journal of Earth and Life Science

Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …

Salinity Effects On Cu(Ii) Bioremediation By Chlamydomonas Reinhardtii Microalgae, Jennifer Hughes

Honors Undergraduate Theses

Microalgae offer a sustainable approach to wastewater treatment by removing pollutants such as excess nutrients, CO₂, and heavy metals. Among various species, Chlamydomonas reinhardtii shows strong potential in removing Cu(II) ions from wastewater. In addition, salinity stress in C. reinhardtii has been linked to morphological and metabolic changes that enhance lipid and phytochemical production. While salinity stress has been studied for enhancing biofuel production, its impact on microalgal removal of heavy metals, particularly Cu(II), remains largely unexplored. Understanding how varying salinity conditions affect both algal growth and the efficiency of Cu(II) remediation could provide critical insights for improving integrated wastewater …

Characterizing The Quorum Sensing (Qs) System In The Model Eukaryote Chlamydomonas Reinhardtii, Kirstin Donnette Cutshaw

Theses and Dissertations

Group behaviors in microorganisms are often regulated by low-molecular weight molecules that enable them to sense population density, a signaling system known as quorum sensing (QS). QS in prokaryotes has provided insight into the role ‘social’ behaviors play in the bacterial world and refined our models of virulence, bacterial motility, and more. While less common, similar behaviors are observed in certain fungi, primarily yeasts, in which QS controls cell morphology, biofilm production, and other phenotypes. We have recently pursued the potential for QS to be more broadly distributed among unicellular eukaryotes, which could significantly alter our understanding of social behaviors …

Climate And Shared Evolutionary History Drive Trait Variation Among Species Of Neotropical Understory Monocots, Eleinis Ávila-Lovera, Oscar M. Vargas, Jennifer L. Funk, Kathleen M. Kay, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Environmental variation commonly drives functional trait diversity within species, among species, and across communities. Climate and shared evolutionary history can both influence trait–environment relationships. We studied variation in plant functional traits among closely related Costus species occurring across environmental gradients, the extent to which this variation occurs within single species, and how that variation may be influenced by shared evolutionary history. We measured leaf, aboveground stem, rhizome, and fine root traits of 17 species of Costus in eight sites in Costa Rica and Panama, which varied in elevation, temperature, and precipitation. We then assessed the relationships among traits and environmental …

Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel

Honors Theses

Coastal dune ecosystems are globally distributed ecosystems that occur from the tropics to the poles and serve as the first line of defense during storms. They are critical habitats for a variety of organisms and also play a critical role in stabilizing coastal habitats. These systems face increased pressure via urban development, recreational expansion, and sea-level rise (Newman et al. 2023; Webster et al. 2005). Insects are vital consumers in coastal ecosystems and act as regulators of plant growth. Low-diversity ecosystems, like coastal dune systems, often contain a higher abundance of low-diverse insect consumers (Ripple et al. 2021), which can …

Multiple Light Signaling Pathways Control Solar Tracking In Sunflowers, Christopher J. Brooks, Hagop S. Atamian, Stacey L. Harmer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Sunflowers are famous for their ability to track the sun throughout the day and then reorient at night to face east the following morning. This occurs by differential growth patterns, with the east sides of stems growing more during the day and the west sides of stems growing more at night. This process, termed heliotropism, is generally believed to be a specialized form of phototropism; however, the underlying mechanism is unknown. To better understand heliotropism, we compared gene expression patterns in plants undergoing phototropism in a controlled environment and in plants initiating and maintaining heliotropic growth in the field. We …

Lichens Of Iller Creek: A Checklist For The Iller Creek Unit, A Division Of Dishman Hills Conservation Area, Spokane Valley, Wa, Devin M. Mumey, Giovanna Bishop, Jessica L. Allen

2023 Symposium

The field of biodiversity documentation encompasses a broad range of research including new species discovery and description, compilation of species present in a given area, and investigation of interspecies interaction. In an era of increasingly devastating and rapid environmental change, documenting biodiversity has become increasingly important. Anthropogenic effects on urban-adjacent natural areas are especially significant, as they can cause numerous, often drastic, responses in ecosystems. Our objective here was to document the lichen biodiversity in a large urban-adjacent protected area: the Iller Creek Unit of the Dishman Hills Conservation Area in Spokane Valley, Washington. This unit encompasses a diversity of …

Isolation Of Arabidopsis Thaliana Plants Homozygous For An Insertional Inactivation Mutation Within Atprp4., Sydney Raitz, Timothy D. Trott

Research in Biology

The AtPRP4 gene in Arabidopsis thaliana has been shown to function in several specific parts of the plant’s cell wall. It is shown to be expressed in the seeds, radicles, roots, leaves, inflorescences, and embryos of Arabidopsis thaliana. These patterns have suggested unique functions for ATPRP4 in determining cell-type-specific wall structure during the development of a plant as well as contributing to defense reactions against physical damage to the plant and pathogen infection within the plant. In this study, a simple DNA prep was performed on the true leaves of Arabidopsis thaliana. Subsequent PCR reactions were performed using …

Cadmium And Salinity Stressor Antagonism On Vallisneria Neotropicalis, Christopher P. Mikolaitis

Graduate Theses and Dissertations (2019 - present)

Submerged macrophytes form the foundation of freshwater ecosystems. These organisms are sessile and are very susceptible to shifts in their environment. Heavy metals are of particular concern as they can be sequestered indefinitely in sediments and are readily taken up by rooted vegetation. In the presence of saltwater intrusions, these metals can interact with salt ions potentially changing their availability to submerged vegetation. In this study a freshwater macrophyte, Vallisneria neotropicalis, was used as a test species for interactive effects between Cd, a non-essential heavy metal, and salt stress. The metrics used to establish the individual as well as …

Where The Wild Mushrooms Are: Species And Secondary Metabolite Diversity In Fungal Species On The Saint Mary’S College Campus, Lex K. Gilman

2023 Midwest Ecology & Evolution Conference

Secondary metabolites in fungi have three main ecological functions: protection against predation, communication with other mushrooms, and assistance in pathogenic interactions. These compounds have also led to the common use of mushrooms as food and in traditional Chinese or other medicinal applications. However, there are currently few good resources for identifying mushroom species in North-Central Indiana. In addition, limited research exists on secondary metabolites in mushrooms. The objective of this research was to create a preliminary database of mushroom species at Saint Mary’s College and conduct preliminary research on the secondary metabolites of these local species. Fungal specimens were identified …

Effects Of Heavy Metal Uptake On Growth, Chlorophyll Content, And Calcium Oxalate Crystals In Lemna Minor (Duckweed), Olivia F. Miller

Undergraduate Honors Thesis Projects

Lemna minor L., duckweed, is a common aquatic plant used for the phytoremediation of wastewater. Heavy metal contamination poses a significant issue, and numerous studies have been conducted on the efficiency of L. minor’s hyperaccumulation ability of these metals. Calcium oxalate crystals are an important aspect of the growth and development of L. minor, but how they are influenced by the uptake of heavy metal has not been extensively studied. This study aims to determine the effects that lead, cadmium, and copper have on the formation of calcium oxalate crystals, vegetative growth, and chlorophyll a and b content on L. …

Getting To The Root Cause: The Genetic Underpinnings Of Root System Architecture And Rhizodeposition In Sorghum, Farren Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Plants are some of the most diverse organisms on earth, consisting of more than 350,000 different species. To understand the underlying processes that contributed to plant diversification, it is fundamental to identify the genetic and genomic components that facilitated various adaptations over evolutionary history. Most studies to date have focused on the underlying controls of above-ground traits such as grain and vegetation; however, little is known about the “hidden half” of plants. Root systems comprise half of the total plant structure and provide vital functions such as anchorage, resource acquisition, and storage of energy reserves. The execution of these key …

Above- And Below-Ground Functional Trait Coordination In The Neotropical Understory Genus Costus, Eleinis Ávila-Lovera, Gregory R. Goldsmith, Kathleen M. Kay, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The study of plant functional traits and variation among and within species can help illuminate functional coordination and trade-offs in key processes that allow plants to grow, reproduce and survive. We studied 20 leaf, above-ground stem, below-ground stem and fine-root traits of 17 Costus species from forests in Costa Rica and Panama to answer the following questions: (i) Do congeneric species show above-ground and below-ground trait coordination and trade-offs consistent with theory of resource acquisition and conservation? (ii) Is there correlated evolution among traits? (iii) Given the diversity of habitats over which Costus occurs, what is the relative contribution of …

Three Lc-Ms Plant Metabolomics Studies Of Hop (Humulus) Species: Wild H. Neomexicanus, Drought Stress, And Agricultural Terroir, Taylan Morcol

Dissertations, Theses, and Capstone Projects

The hop plant (Humulus L., Cannabaceae) is a dioecious, perennial, twining vine with a long history of human use. Nowadays, hop plants are generally grown for their inflorescences (“cones”), which are used in brewing for their phytochemical metabolites. Many of these metabolites are involved in plant stress response and communication. Genetics and environment are two major factors that affect plant metabolism. In three separate metabolomics studies, this project examined the effects of both genetic and environmental factors on hop phytochemistry.

In the first study, 23 hop genotypes were grown in two different locations in the Pacific Northwest region of …

Seed Rain–Successional Feedbacks In Wet Tropical Forests, Nohemi Huanca Nuñez, Robin L. Chazdon, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

Abstract

Tropical forest regeneration after abandonment of former agricultural land depends critically on the input of tree seeds, yet seed dispersal is increasingly disrupted in contemporary human-modified landscapes. Here, we introduce the concept of seed rain–successional feedbacks as a deterministic process in which seed rain is shaped by successional dynamics internal to a forest site and that acts to reinforce priority effects. We used a combination of time series and chronosequence approaches to investigate how the quantity and taxonomic and functional composition of seed rain change during succession and to evaluate the strength of seed rain–successional feedbacks, relative to other …

A Microbiome Engineering Framework To Evaluate Rhizobial Symbionts Of Legumes, Kenjiro W. Quides, Hagop S. Atamian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background

For well over a century, rhizobia have been recognized as effective biofertilizer options for legume crops. This has led to the widespread use of rhizobial inoculants in agricultural systems, but a recurring issue has emerged: applied rhizobia struggle to provide growth benefits to legume crops. This has largely been attributed to the presence of soil rhizobia and has been termed the ‘rhizobial competition problem.’

Scope

Microbiome engineering has emerged as a methodology to circumvent the rhizobial competition problem by creating legume microbiomes that do not require exogenous rhizobia. However, we highlight an alternative implementation of microbiome engineering that focuses …

Assessing Short-Term Microalgal Community Responses Over Altering Hydrological Conditions In Experimental Wetlands Of Costal Georgia, Maggie M. Kuhn

College of Graduate Studies: Theses & Dissertations

Wetlands provide valuable ecosystem services such as nutrient cycling and carbon storage. Microalgae (i.e., diatoms) provide the foundation of primary production and determine rates of energy transfer throughout the system. Climate change models predict an increase in frequency of intense storms and severe drought conditions that pose a threat to known hydrological regimes and wetland ecosystem stability. The purpose of my study was to assess the effects of water permanence (i.e., duration of flooding) on diatom community structure in experimental wetlands. I predicted that wetlands with prolonged periods of flooding (i.e., permanent) would harbor a consistent diatom community throughout flooding …

Lichens And Biofilms: Common Collective Growth Imparts Similar Developmental Strategies, Erin C. Carr, Steven D. Harris, Joshua R. Herr, Wayne Riekhof

Department of Plant Pathology: Faculty Publications

Lichens are traditionally defined as a symbiotic relationship between fungi and algae and/or cyanobacteria. This union forms a unique structure called the thallus, which attaches to surfaces such as rocks and tree bark. Recent reports challenge the view that lichens are comprised of one fungus and one photobiont, and instead suggest that they are a consortium of microbes. Much of lichen biology remains unknown as most of our knowledge of lichens is limited to morphological characteristics with little to no functional analysis of lichen genes. However, lichens and biofilms share many similar physiological traits which when compared may assist in …

The Mechanisms And Consequences Of Shrub Encroachment On The Virginia Barrier Islands, Lauren K. Wood

Theses and Dissertations

Shrub encroachment is a global phenomenon driven by direct and indirect anthropogenic influence which alters plant communities and ecosystem function. Many studies have investigated drivers and consequences of woody plant establishment, but mesic landscapes are underrepresented in the literature. My objective was to assess the mechanisms of Morella cerifera encroachment into coastal mesic grassland, the potential for self-reinforcement, and consequences on community composition, nutrients, and landscape productivity. I studied temperature and water microclimate modification by Morella cerifera presence and removal to understand ecosystem engineering and community composition changes. Additionally, I examined the influence of shrubs on surrounding grassland species traits …

De Novo Sequencing And Analysis Of Salvia Hispanica Tissue-Specific Transcriptome And Identification Of Genes Involved In Terpenoid Biosynthesis, James Wimberley, Joseph Cahill, Hagop S. Atamian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Salvia hispanica (commonly known as chia) is gaining popularity worldwide as a healthy food supplement due to its low saturated fatty acid and high polyunsaturated fatty acid content, in addition to being rich in protein, fiber, and antioxidants. Chia leaves contain plethora of secondary metabolites with medicinal properties. In this study, we sequenced chia leaf and root transcriptomes using the Illumina platform. The short reads were assembled into contigs using the Trinity software and annotated against the Uniprot database. The reads were de novo assembled into 103,367 contigs, which represented 92.8% transcriptome completeness and a diverse set of Gene Ontology …

Comparison Of The Effects Of Growing-Season Burns And Dormant-Season Burns On Vegetation Structure And Grassland Bird Diversity In East-Central Illinois Prairies, Joseph Lee Boise

Masters Theses

For managed grasslands, prescribed burns are a method to manage species composition by preventing crowding by bunch grasses and woody encroachment. While dormant-season (spring) burns are routinely performed, managers have recently introduced growing-season (late summer/fall) burns to prairies in east-central Illinois. The purpose of this study was to compare the effects of dormant-season and growingseason burns on vegetation structure and associated avian diversity. Specifically, objectives were to determine if: (1) Growing-season burns increase bird diversity or density of rare/declining species relative to dormant season burns; (2) Growing-season burns cause more bare ground to open and reduce litter and woody species …

Vines In The Neotropics: Phylogenomics, Biogeography And Systematics In Passion Flowers (Passiflora Subgenus Decaloba Section Decaloba), Serena Acha

Dissertations

With 600 species, Passiflora is a large, morphologically complex and broadly distributed genus in Passifloraceae that represents a major challenge to scientists interested in understanding the evolutionary history of tropical vines. Passiflora has been divided into subgenera, super sections and sections. One of the most enigmatic and species-rich (~120 spp.) groups in Passiflora is section Decaloba, which occurs in the Neotropics and is particularly diverse in Andean montane forests. In this study, we used phylogenomic and population genomic approaches to investigate the evolutionary history, biologeography, species boundaries, and taxonomy of Passiflora section Decaloba. We sampled herbarium specimens, extracted …

Seasonal Origins Of Soil Water Used By Trees, Scott T. Allen, James W. Kirchner, Sabine Braun, Rolf T. W. Siegwolf, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Rain recharges soil water storages and either percolates downward into aquifers and streams or is returned to the atmosphere through evapotranspiration. Although it is commonly assumed that summer rainfall recharges plant-available water during the growing season, the seasonal origins of water used by plants have not been systematically explored. We characterize the seasonal origins of waters in soils and trees by comparing their midsummer isotopic signatures (δ2H) to seasonal isotopic cycles in precipitation, using a new seasonal origin index. Across 182 Swiss forest sites, xylem water isotopic signatures show that summer rain was not the predominant water source …

Relationship Of Ndvi And Oak (Quercus)Pollen Including A Predictive Model In The Sw Mediterranean Region, Rocío González-Naharro, Elia Quirós, Santiago Fernández-Rodríguez, Inmaculada Silva-Palacios, J. M. Maya-Manzano, Rafael Tormo-Molina, Raúl Pecero-Casimiro, Alejandro Monroy-Colin, Ángela Gonzalo-Garijo

Articles

Techniques of remote sensing are being used to develop phenological studies. Our goal is to study the correlation among the Normalized Difference Vegetation Index (NDVI) related with oak trees included in three set data polygons (15, 25 and 50 km to aerobiological sampling point as NDVI-15, 25 and 50), and oak (Quercus) daily average pollen counts from 1994 to 2013. The study was developed in the SW Mediterranean region with continuous pollen recording within the mean pollen season of each studied year. These pollen concentrations were compared with NDVI values in the locations containing the vegetation under a study based …

Foraging Preferences Of Barnacle Geese On Endophytic Tall And Red Fescues, Tuuli-Marjaana Koski, Kari Saikkonen, Tero Klemola, Marjo Helander

Human–Wildlife Interactions

Many grasses (Poaceae) have symbiotic fungal endophytes, which affect livestock by producing unpalatable or harmful secondary compounds. Less is known about the repelling effects of fungal endophytes on avian grazers despite potential wildlife management implications. Herbivorous goose (Branta spp.) species may become a nuisance in recreational use areas via fecal littering. Planting these areas with grasses that avian grazers avoid may help mitigate this damage. In 2016, we studied the foraging preference of the barnacle geese (B. leucopsis) with endophytic (E+) or endophyte-free (E-) red fescue (Festuca rubra) and/or tall fescue (Schedonorus phoenix) in …