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Oxalic Acid Leaf Disk Soak Assay Is A New Possibility In Screening For Blight Resistance In Castanea Species, Kaitlyn Harden May 2023

Oxalic Acid Leaf Disk Soak Assay Is A New Possibility In Screening For Blight Resistance In Castanea Species, Kaitlyn Harden

Honors Theses

Chestnut blight is a disease caused by the ascomycete fungus Cryphonectria parasitica in the Castanea species. The fungus uses oxalic acid (OA) to attack the tree’s cells. Castanea dentata, the American chestnut, was wiped out by chestnut blight in the early to mid-20th century, but several East Asian Castanea species appear highly resistant to the fungus. To breed resistant American type trees, screening methods are used to enable selection of interspecific hybrids. The alternative small stem assay (aSSA) is a method of screening container-grown hybrid seedlings during their first growing season by directly infecting them with C. parasitica. Some plant …


A Small Stem Assay Using Hypovirulent Cryphonectria Parasitica To Screen Castanea Dentata Backcross F2 Families May Set The Stage For Long-Term Survival, Trish Nguyen May 2023

A Small Stem Assay Using Hypovirulent Cryphonectria Parasitica To Screen Castanea Dentata Backcross F2 Families May Set The Stage For Long-Term Survival, Trish Nguyen

Honors Theses

By combining the results of blight resistance breeding and the application of hypovirulence as a biocontrol, populations of resistant hybrid trees could be deployed together with a less pathogenic strain of Cryphonectria parasitica (Murr.) Barr. I used a small stem assay to screen seedlings in thirteen half-sibling backcross F2 families with an attenuated strain of C. parasitica containing the Cryphonectria parasitica hypovirus-1 (CHV-1) Euro7 virus. The experiment was set up as a randomized complete block design in 2-gallon containers. Measurements of canker length and morphology were gathered at 90 days post-inoculation. Although statistically significant differences were seen between canker lengths …


Bryophytes Of Goochland County, Virginia, Mikayla Quinn Apr 2023

Bryophytes Of Goochland County, Virginia, Mikayla Quinn

Honors Theses

Bryophytes are non-vascular land plants that include mosses, liverworts, and hornworts. Although easier to overlook because of their smaller size, bryophytes are a fundamental part of the ecosystem. As such, maintaining record of their biodiversity is important. Yet, records of bryophyte species in Goochland County, VA were low compared to more thoroughly documented counties such as Prince Edward County. This study expands the documentation of bryophyte flora and presents a checklist of bryophyte species found Virginia’s Goochland County from 2020-2023. Fieldwork conducted at public and privately-owned properties throughout the county between January 2020 and March 2023 yielded 702 specimens that …


Heading For A Breakdown: Assessing Evolution Through The Hybridization Of Two Sexual Systems, Diamanda A. Zizis Jan 2023

Heading For A Breakdown: Assessing Evolution Through The Hybridization Of Two Sexual Systems, Diamanda A. Zizis

Honors Theses

Hybridization is an important evolutionary pathway that has contributed to the world’s vast biodiversity. In plants, especially angiosperms, hybridization is known to be an important mechanism for speciation, phenotypic divergence, and changes in reproductive systems. Solanum species present an ideal system to investigate how hybridization between two different sexual systems impacts the reproductive and phenotypic biology of the hybrid progeny. Hybrid seeds were acquired from crosses between Australian Solanum species Solanum dioicum (dioecious) and S. ultraspinosum (andromonoecious) in order to track what happens when you cross two plants with different sexual systems. Vegetative and floral morphological measurements were conducted, and …


Changes In Ecosystem Processes And Functional Traits Over An Elevational Gradient, Tiana Issa Jan 2023

Changes In Ecosystem Processes And Functional Traits Over An Elevational Gradient, Tiana Issa

Honors Theses

Elevation gradients have been used to understand how climate change impacts various ecosystems processes by substituting distance across elevation with time, reflecting a previous, colder climate. To monitor the changes in soil organic carbon (SOC), plant community, and functional traits across time in the face of climate change, this study used space-for-time substitution to emulate a long-term study with elevational gradients and revisited the same gradient for nearly two decades to monitor elevational effects across time. With this research, I aim to answer the following questions: (1) How does elevation impact ecosystem processes and alpine plant traits? (2) How does …


Effects Of Red Light Intensity On Cultivation & Oxygen Production In Arthrospira Plantensis, Abigail Roberts Dec 2022

Effects Of Red Light Intensity On Cultivation & Oxygen Production In Arthrospira Plantensis, Abigail Roberts

Honors Theses

Maintaining life sustaining resources during long-term space travel has encouraged scientists to turn their attention to the potential benefits of a cyanobacteria named Arthrospira platensis, commonly known as Spirulina algae. This experiment measures the oxygen production and cell population growth of two structurally different Spirulina cultures under two different levels of red light intensities, 8 µmol/m 2Js (high); 3 µmol/m2/s (low). The cell population, oxygen produced, and oxygen produced per cell measurements were observed and recorded at three 24 hour intervals. It was found there was not a significant difference between high and low light intensities when considering the cell …


A Small Stem Assay For Chestnut Blight Resistance In Hybrid American Chestnut Trees, Evelyn Odle May 2022

A Small Stem Assay For Chestnut Blight Resistance In Hybrid American Chestnut Trees, Evelyn Odle

Honors Theses

Cryphonectria parasitica (Murr.) Barr is the causal agent for the chestnut blight disease, which was brought to North America in the late 19th century on nursery stock from Japan (Anagnostakis 1987). A pandemic of chestnut blight lasted for the next half century, nearly wiping out all American chestnut trees (Castanea dentata Borkh.). Restoration works to restoring the American chestnut to its native range in North America’s canopy has been going on for the past century. The American Chestnut Foundation has strived to breed a resistant American chestnut by backcross breeding with Chinese species (C. mollissima Blume) since the 1980s. The …


The Effect Of Clay On The Inhibitory Effect Of Mustard Seed Meal On Velvetleaf Seedling Growth, Heeyun Oh Apr 2022

The Effect Of Clay On The Inhibitory Effect Of Mustard Seed Meal On Velvetleaf Seedling Growth, Heeyun Oh

Honors Theses

Mustard seed meal (MSM) has been studied as a biofumigant in suppressing weed growth in an organic-friendly way. Previous studies have shown that MSM in the presence of elevated sand content was highly effective in suppressing the germination of velvetleaf seeds, and that as clay/silt in sand content increased, MSM effectiveness decreased in suppressing seed germination. Based on these results, it was postulated that clay may have effects on MSM by inhibiting this biofumigant from suppressing weed growth. Two different types of pure clay--kaolin and montmorillonite--were selected with their increasing concentrations. Low concentrations of clay do not seem to influence …


A Rapid Species-Specific Diagnostic Assay For Xylaria Necrophora, The Pathogen Behind Taproot Decline Of Soybean In The Southern United States, Sophie Baron Sheffield Apr 2022

A Rapid Species-Specific Diagnostic Assay For Xylaria Necrophora, The Pathogen Behind Taproot Decline Of Soybean In The Southern United States, Sophie Baron Sheffield

Honors Theses

No abstract provided.


Modeling Jadera Haematoloma’S Phenotypic Variation In The Context Of Its Developmental Plasticity, Michael C. Yorsz Jan 2022

Modeling Jadera Haematoloma’S Phenotypic Variation In The Context Of Its Developmental Plasticity, Michael C. Yorsz

Honors Theses

Phenotypic plasticity is the ability of an organism to integrate information from environmental cues to inform the development of its phenotype and remains understudied in biology. Models of plasticity are needed because evolution in the presence of plasticity is poorly understood. Jadera haematoloma, a hemimetabolous true bug, is an excellent animal model of plasticity, exhibiting a non-linear plastic response to juvenile nutrition that biases adult development into groups with differences in flight capability, wing shape, and fecundity. However, there is a lack of literature consensus regarding the range of developmental outcomes in the species. Some publications report the presence …


Exploring Secondary Metabolite Profiles Of Sloth Algae, Valerie Quach, Paige Smith May 2021

Exploring Secondary Metabolite Profiles Of Sloth Algae, Valerie Quach, Paige Smith

Honors Theses

In this experiment, we investigated the composition of the secondary metabolites in sloth algal cultures. Additionally, we investigated the effects of secondary metabolites in sloth algal cultures on insects. The three outlets of investigation include insect avoidance tests, sending samples to the Natural Center for Natural Products Research, and analyzing sequencing data with AntiSMASH to identify secondary metabolite biosynthetic gene clusters. While our data from the Drosophila fly tests were inconclusive, we found that our samples contain many different gene clusters for terpenes, NRPS, PKS, RiPPs, which are volatile compounds with a wide array of biosynthetic functions. This research can …


Responses Of The Carnivorous Pink Spoonleaf Sundew (Drosera Capillaris) To Nitrogen Addition, Phosphorus Addition, And Simulated Fire, Karina Rodriguez Castillo May 2021

Responses Of The Carnivorous Pink Spoonleaf Sundew (Drosera Capillaris) To Nitrogen Addition, Phosphorus Addition, And Simulated Fire, Karina Rodriguez Castillo

Honors Theses

This study investigated how the carnivorous plant, Drosera capillaris(pink sundew), responded to changes in the resources of its habitat, the fire-prone, nutrient-poor wet savannas. It is of interest to determine what soil nutrient(s), nitrogen or phosphorus, limits the survival and growth of pink sundew, and to what extent, if any, does fire affect the survival and growth of this carnivorous plant. My field experiments had twenty plots with two replicate groups consisting of four pink sundews in each plot. From the fall of 2017 to the fall of 2019, only half of the plots were clipped annually, and there …


The Importance Of A Multidisciplinary Approach To Public Health: Addressing Food Insecurity Through A Biological And Sociological Lens, Chloe Grant May 2021

The Importance Of A Multidisciplinary Approach To Public Health: Addressing Food Insecurity Through A Biological And Sociological Lens, Chloe Grant

Honors Theses

Plants can sense the change of 1 oC in their growth environment and thus global climate change has a great impact on plant growth and development. The phenomenon that warm non-stress temperatures promote stem and petiole elongation, as well as leaf hyponastic growth, is collectively known as thermomorphogenesis. While it is known that the basic helix-loop-helix (bHLH) transcription factor PIF4 is highly inducible by temperature elevations and controls thermomorphogenesis in dicots (e.g., Arabidopsis thaliana), the molecular mechanism underlying thermomorphogenetic growth in monocots is not clear. In this study, I identify PIF4 orthologs in several economically important monocotyledonous species and …


An Analysis Of The Pollinators Of Echinacea Purpurea In Relation To Their Perceived Efficiency And Color Preferences, Carmen Black May 2021

An Analysis Of The Pollinators Of Echinacea Purpurea In Relation To Their Perceived Efficiency And Color Preferences, Carmen Black

Honors Theses

This study aimed to better understand how insects interacted with species of Echinacea in Tennessee and specifically their preference to floral color. Based on previous studies I expected the main visitors to be composed of various bees, beetles and butterflies. Based on previous studies, I hypothesized that most bees (especially social bees) would most likely pollinate the purple/violet morphs of the flower versus the white morph. I also expected the bees would have the most visits to the coneflowers versus any other taxonomic group. I believe bees to be the majority of pollinators based upon the results of Stucky, Gadd, …


A Baseline Documentation Report For The Delta Wind Birds Sky Lake Nature Reserve, James Dubberly Apr 2021

A Baseline Documentation Report For The Delta Wind Birds Sky Lake Nature Reserve, James Dubberly

Honors Theses

The purpose of this baseline documentation is to conduct a report on our subject property and discuss the findings. A conservation easement is established by upholding a certain standard of a property’s current condition which makes a baseline documentation necessary for an easement to be enacted. Baseline documentation reports are used as a resource to monitor and enforce the legal agreements of the conservation easement. The subject property is currently owned by the Delta Wind Birds organization. In our scenario, this documentation report will serve to aid in the conversion of our subject property into a conservation easement in which …


Transcriptional Activation Of Phytochrome-Interacting Factor 4 Is A Conserved Mechanism Of Thermomorphogenesis In Dicotyledenous Plants, Caroline Clutton Apr 2021

Transcriptional Activation Of Phytochrome-Interacting Factor 4 Is A Conserved Mechanism Of Thermomorphogenesis In Dicotyledenous Plants, Caroline Clutton

Honors Theses

In the model dicotyledonous plant Arabidopsis thaliana, the basic helix-loop-helix (bHLH) transcription factor Phytochrome-Interacting Factor 4 (AtPIF4) plays a central role in regulating the ambient temperature-regulated hypocotyl growth response. Warm temperatures induce AtPIF4 transcription and the accumulated AtPIF4 promotes thermomorphogenesis by enhancing the expression of a group of growth-related genes. However, whether this thermo-induced growth response is universal, and more importantly, whether there is a conserved thermomorphogenetic mechanism shared in dicots is largely unknown. Here we show that higher ambient temperatures promote the hypocotyl growth in four other dicotyledonous plants, including Brassica rapa, Camelina sativa, Nicotiana benthamiana …


A Baseline Documentation Report For The Delta Wind Birds Sky Lake Nature Reserve, Preston T. Perkins, J Hays Dubberly, Michael J. Thomas Apr 2021

A Baseline Documentation Report For The Delta Wind Birds Sky Lake Nature Reserve, Preston T. Perkins, J Hays Dubberly, Michael J. Thomas

Honors Theses

The purpose of this baseline documentation is to conduct a report on our subject property and discuss the findings. A conservation easement is established by upholding a certain standard of a property’s current condition which makes a baseline documentation necessary for an easement to be enacted. Baseline documentation reports are used as a resource to monitor and enforce the legal agreements of the conservation easement. The subject property is currently owned by the Delta Wind Birds organization. In our scenario, this documentation report will serve to aid in the conversion of our subject property into a conservation easement in which …


Genetic Diversity & Connectivity Of Chasmanthium Latifolium (Poaceae) In Pennsylvania & The Effect On Conservation Status Of A Rare Species, Jonathan D. Hayes Jan 2021

Genetic Diversity & Connectivity Of Chasmanthium Latifolium (Poaceae) In Pennsylvania & The Effect On Conservation Status Of A Rare Species, Jonathan D. Hayes

Honors Theses

Chasmanthium latifolium (Michx.) Yates (Poaceae) is a loosely colonial, rhizomatous, perennial grass species that lives in riparian habitats, making it fittingly referred to as river oats. Native to the southern Midwest and the eastern half of the United States, C. latifolium reaches the northeastern edge of its range in Pennsylvania. Within Pennsylvania, eleven extant C. latifolium populations are found along four waterways: the Monongahela River, the Susquehanna River, and two tributaries to the Susquehanna River. This limited state distribution exhibits an east-west disjunct distribution, where western populations are largely separated from eastern populations with one centrally located population. Between the …


A Meta-Analysis Of The Human Uses Of Pteridophytic Species In Tennessee, Diana Sevier Aug 2020

A Meta-Analysis Of The Human Uses Of Pteridophytic Species In Tennessee, Diana Sevier

Honors Theses

Pteridophytes are an ancient lineage of plants, composed of ferns and fern allies, which are spread across the globe. There is also a long record of humans using pteridophytes to their benefit, which includes the broad categories of medicine, ornamentation, food, phytoremediation, and agriculture. Understanding these concepts, the goal of this thesis was to conduct a meta-analysis which pulled together data from many resources on the 94 Tennessee pteridophyte species to create a repository of human use information, as well as to examine, analyze, and comment on the trends present within and between taxonomic groups of pteridophytes. The methods used …


Analyzing Thermal Gradients Using Terrestrial Laser Scanning In Scrub Oak Habitats, Alyssa Silbey Jun 2020

Analyzing Thermal Gradients Using Terrestrial Laser Scanning In Scrub Oak Habitats, Alyssa Silbey

Honors Theses

Thermal microclimates are an important component of natural ecosystems because they provide appropriate niche space for many organisms; however, they are not widely studied because of their small scale. Likewise, variation in these microclimates may significantly impact animal thermoregulation and plant physiological processes and be especially important in the face of climate change. The goal of this study is to determine how the size and structure of Quercus ilicifolia shrubs influences ground temperature gradients. We hypothesized that differences in leaf cover and leaf area index (LAI) would cause temperature under shrubs to cool relative to the ambient temperature, and that …


A Contribution To The Macrofungi Of Cloudland Canyon State Park, Peyden Valentine May 2020

A Contribution To The Macrofungi Of Cloudland Canyon State Park, Peyden Valentine

Honors Theses

I conducted a survey of the macroscopic fungi within Cloudland Canyon State Park, Dade County, GA that consisted of twenty-three forays from May through December of 2019, and one foray in March 2020. The results of my survey add baseline data to our knowledge of the mushrooms present within the park, allow for the future construction of an All Taxa Biodiversity Index, and allow comparisons to other surveys of fungal diversity in similar areas of the Cumberland Plateau: the Tennessee River Gorge Trust (Starrett 2005), and the Lula Lake Land Trust (De Guzman 2000). My survey resulted in an overall …


A Contribution To The Characterization Of The Diversity Of Ectomycorrhizal Fungi Associated With American Chestnut At The Utc Fortwood Street Nursery, Colton Jones May 2020

A Contribution To The Characterization Of The Diversity Of Ectomycorrhizal Fungi Associated With American Chestnut At The Utc Fortwood Street Nursery, Colton Jones

Honors Theses

Ectomycorrhizas play several essential roles in the biosphere and have immeasurable implications on the ecosystems in which they exist. Much has been discovered about the relationships between ectomycorrhizal fungi and the trees with which they associate, but there is still much to learn. Due to the nature of ectomycorrhizal morphology, DNA analysis is frequently required in order to accurately identify the fungal partner. Some ectomycorrhizal fungi produce above-ground fruiting bodies that presumably contain the same DNA sequences as the fungi encapsulating corresponding plant root tips below the soil; these fruiting bodies have been frequently observed growing in nursery containers at …


Checklist Of The Vascular Flora, Restoration Plans, And Educational Interpretive Signs For A Remnant Prairie At The Lakewood Memorial Cemetery, Hinds County, Mississippi, Olivia Shelton May 2019

Checklist Of The Vascular Flora, Restoration Plans, And Educational Interpretive Signs For A Remnant Prairie At The Lakewood Memorial Cemetery, Hinds County, Mississippi, Olivia Shelton

Honors Theses

A floristic survey was conducted on the eastern margin of the Lakewood Memorial Park Cemetery, located between Jackson and Clinton, Mississippi, near the western edge of the Jackson Prairie ecoregion. From soil map data and preliminary observations of the landform and flora, the eastern part of the cemetery was hypothesized to be remnant prairie now mostly covered by exotic grasses (pasture) and woodland. Plant specimens were collected, identified, and preserved in the herbarium of The University of Southern Mississippi (USMS). The survey yielded 119 species of vascular plants, of which 98 (82%) were native and 21 (18%) were non-native. Indicative …


Use Of Co-Immunoprecipitations And 2d Gel Electrophoresis To Identify Protein-Protein Interactions Of Maturase K, Lauren Angello Dec 2018

Use Of Co-Immunoprecipitations And 2d Gel Electrophoresis To Identify Protein-Protein Interactions Of Maturase K, Lauren Angello

Honors Theses

Maturase K (MatK) is the only group II intron encoded protein in the chloroplast of land plants. Maturases are prokaryotic enzymes that catalyze formation of the lariat structure needed for intron removal from precursor RNAs. The chloroplast maturase MatK, is a descendant of prokaryotic maturases, however, unlike its prokaryotic relatives, MatK is thought to catalyze excision of, not only its own intron, but also the introns of other group II introns in the plastome. Similar to the multiprotein and snRNA spliceosomal complex of the nucleus, it is postulated that MatK is not working alone to excise these introns but most …


Biological Soil Crusts In A Northeastern Pine Barren: Composition And Ecological Effects, Jessica Gilbert Jun 2018

Biological Soil Crusts In A Northeastern Pine Barren: Composition And Ecological Effects, Jessica Gilbert

Honors Theses

Biological soil crusts (BSCs), otherwise known as cryptogamic soil crusts, biocrusts, or cyanobacterial crusts, are soil aggregations hosting diverse biotic communities. They are composed of cyanobacteria and algae, and generally have a covering of moss and/or lichen. BSCs are typically found in arid to semi-arid regions throughout the world, and are integral soil stabilizers, moisture retainers, and nitrogen fixers in these communities. Along with these factors, BSCs are able to impact germination and establishment of plants, either as an accompanying influence, or direct result of those listed above. BSCs have yet to be formally described in the inland northeastern United …


On The Maintained Significance Of Botanical Illustration In Modern Plant Identification Guides, Andi Kur May 2018

On The Maintained Significance Of Botanical Illustration In Modern Plant Identification Guides, Andi Kur

Honors Theses

This project began over 2.5 years ago when I, an artist by hobby, contacted Dr. Joey Shaw, the director of the Herbarium at the University of Tennessee Chattanooga, with a request to sketch from specimens in the UCHT collection. Dr. Shaw, fortuitously in need of an illustrator, prompted me with the opportunity to collaborate with him in the creation of illustrations for the second edition of the Guide to the Vascular Plants of Tennessee. From here, this project has grown as we have attempted to determine the most effective way to illustrate the guide, our questions manifesting in a myriad …


Investigating Phosphorylation Patterns And Their Effect On The Activity Of Transcription Factor Taabf1 In Imbibing Cereal Grains, Grace Uwase Jan 2018

Investigating Phosphorylation Patterns And Their Effect On The Activity Of Transcription Factor Taabf1 In Imbibing Cereal Grains, Grace Uwase

Honors Theses

The wheat transcription factor TaABF1 plays an important role in hormone-mediated regulation of seed dormancy and germination of cereal grains. Evidence shows that TaABF1 activity is regulated by phosphorylation, and previous work in our lab showed that when serine residues in its conserved regions; S36, S37, S113, S115 were altered to phosphomimetic aspartate, the 4xD TaABF1 mutant had increased activity as a transcription factor. However, when only S113 was altered, TaABF1’s activity was greatly reduced. The work presented here explored whether the S36D/S37D/S115D mutant would have stronger activity than the 4xD mutant. Using the particle bombardment technique to introduce the …


Phylogenetic Relationships Of The Genera Of Achariaceae Based On Analyses Of Morphological And Dna Data, Corey L. Pagart May 2017

Phylogenetic Relationships Of The Genera Of Achariaceae Based On Analyses Of Morphological And Dna Data, Corey L. Pagart

Honors Theses

Achariaceae are a mostly tropical family of flowering plants consisting of about 29 genera and 150 species of trees and shrubs. Although they are closely related to passionflowers (Passifloraceae), violets (Violaceae), and willows and cottonwoods (Salicaceae), phylogenetic relationships of the genera remain unclear because the only studies have been focused on particular genera or had limited sampling. Few studies of the family in general have been conducted, except for some on species that produce chaulmoogra oil, a commonly used historical treatment for leprosy. For my study, I investigated the relationships of the genera within the family using morphological and molecular …


Phylogenetic Relationships Of Salicaceae Based On Analyses Of Nuclear Dna Data, John Marshall Diffey May 2017

Phylogenetic Relationships Of Salicaceae Based On Analyses Of Nuclear Dna Data, John Marshall Diffey

Honors Theses

Salicaceae are an economically and ecologically important family of flowering plants. The family includes willows and cottonwoods and was recently enlarged to include a large number of tropical species formerly placed in the family Flacourtiaceae. Relationships of these tropical relatives to willows and cottonwoods have been explored at a basic level using morphology and plastid DNA data, but to date no molecular phylogenies have been constructed with significant sampling of nuclear DNA, which sometimes results in a different picture of relationships because of its biparental inheritance. For this project, I sampled one region of nuclear DNA (GBSSI) across the family …


Organics: Exploring The Parallels Between Botany And Human Anatomy Through Sculpture And Watercolor Painting, Allison Borek Jun 2016

Organics: Exploring The Parallels Between Botany And Human Anatomy Through Sculpture And Watercolor Painting, Allison Borek

Honors Theses

Integrating my two passions of the visual arts and science for my senior thesis, I created a collection of paintings that represent human organs and the parallels between plant biology and animal biology. Genetically, plants are just as complex – if not more – than many animals. They have intricate sensory and regulatory systems highly comparable to humans, and on a cellular level, we share many analogous features. In addition, every single carbon atom that makes up the human body was at one time fixed in a plant during photosynthesis. We also rely on photosynthesis to give us the oxygen …