Botany Commons^™

Climate Change And Conservation Of Milkweed: Evidence Of Extensive Admixture Between Common Milkweed And Poke Milkweed, Elizabeth Davies

Undergraduate Honors Theses

Global climate change can drive many changes in species interactions. One primary way it affects species is by changing climates, causing species to expand their ranges and allowing them to interact with species from whom they were previously isolated. In plants, new species interactions can result in hybridization – the creation of hybrid offspring between two separate species. This hybridization can increase gene flow between the species and lead to introgression, the transfer of genetic material from one species to another through hybrid backcrossing with the parent species. My thesis investigates hybridization in the model system Asclepias (milkweed) by analyzing …

Investigating The Effect Of Longhorned Milkweed Beetle Larval Root Feeding On Resprouting In Common Milkweed, Margaret Donnan

Undergraduate Honors Theses

Clonal reproduction is an important form of reproduction for many plants, and plants can grow clonally through a variety of methods, such as belowground stems, specialized organs, or adventitious buds on their roots (Herben and Klimešová 2020). In plants that reproduce via buds on their roots, researchers have shown that damage to roots can stimulate bud production and sprouting (Bartušková and Klimešová 2010). Common milkweed (Asclepias syriaca) is a root- sprouting perennial plant that receives yearly damage to its roots via the feeding of the larvae of the specialist longhorned milkweed beetle (Tetraopes tetrophthalmus) (Erwin et al. 2013). In this …

Three Centuries Of Vegetation Change In The William & Mary College Woods Reconstructed Using Phytoliths, Timothy Terlizzi

Undergraduate Honors Theses

The College Woods, west of William & Mary’s campus, consists of ~900 acres of protected southern mixed hardwood forest. The woods surround Lake Matoaka, a former millpond established in ~1700. Despite the rich history of the area, little is known about how the dominant vegetative landcover has shifted over the last 300 years. This study set out to quantify the modern vegetation within the College Woods via the phytolith assemblages within the soil and identify shifts in the assemblages since the creation of Lake Matoaka and whether these changes are distinct from the vegetation that existed in the area before …

The Regulatory Network For Petal Anthocyanin Pigmentation Is Shaped By The Myb5a/Negan Transcription Factor In Mimulus, Xingyu Zheng, Kuenzang Om, Kimmy A. Stanton, (...), Gregory D. Conradi Smith, Joshua R. Puzeyn, Et Al.

Arts & Sciences Articles

Much of the visual diversity of angiosperms is due to the frequent evolution of novel pigmentation patterns in flowers. The gene network responsible for anthocyanin pigmentation, in particular, has become a model for investigating how genetic changes give rise to phenotypic innovation. In the monkeyflower genus Mimulus, an evolutionarily recent gain of petal lobe anthocyanin pigmentation in M. luteus var. variegatus was previously mapped to genomic region pla2. Here, we use sequence and expression analysis, followed by transgenic manipulation of gene expression, to identify MYB5a—orthologous to the NEGAN transcriptional activator from M. lewisii—as the gene responsible …

Subgenome Dominance In An Interspecific Hybrid, Synthetic Allopolyploid, And A 140-Year-Old Naturally Established Neo-Allopolyploid Monkeyflower, Patrick P. Edger, Ronald Smith, Micheal R. Mckain, (...), Gregory D. Conradi Smith, Joshua R. Puzey

Arts & Sciences Articles

Recent studies have shown that one of the parental subgenomes in ancient polyploids is generally more dominant, having retained more genes and being more highly expressed, a phenomenon termed subgenome dominance. The genomic features that determine how quickly and which subgenome dominates within a newly formed polyploid remain poorly understood. To investigate the rate of emergence of subgenome dominance, we examined gene expression, gene methylation, and transposable element (TE) methylation in a natural, <140-year-old allopolyploid (Mimulus peregrinus), a resynthesized interspecies triploid hybrid (M. robertsii), a resynthesized allopolyploid (M. peregrinus), and progenitor species (M. guttatus …

Misregulation Of Genomic Imprinting Drives Abnormal Seed Development In Hybrid Monkeyflowers (Mimulus), Taliesin Kinser

Dissertations, Theses, and Masters Projects

Genomic imprinting is the preferential expression of one allele over the other. It is an epigenetic phenomenon that occurs in the placentas of mammals and the endosperm of angiosperms. Endosperm, like placentas, is a nutrient rich tissue that supports the growing embryo within the seed. All grains are predominantly composed of this tissue. It is the product of a second fertilization event, resulting in both maternal and paternal alleles. Some alleles are regulated differentially, resulting in imprinted genes. There are both paternally expressed imprinted genes (PEGs) and maternally expressed imprinted genes (MEGs) in the endosperm. In general PEGs tend to …

Associated Dataset: Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity And Export, Daniel E. Kaufman, Marjorie A.M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C.P. Hemmings

Data

This dataset includes data used in the publication Kaufman et al., 2017, JGR-Oceans, which investigates how these climatic changes in the Ross Sea, Antarctica, may alter phytoplankton composition, primary productivity and export. A one-dimensional version of the Model of Ecosystem Dynamics, nutrient Utilisation, Sequestration and Acidification was adapted for use in the Ross Sea (MEDUSA-RS). Glider measurements were used to force MEDUSA-RS, which includes diatoms and both solitary and colonial forms of Phaeocystis antarctica. Model performance was evaluated with glider observations, and experiments were conducted using projections of physical drivers for mid- and late-21st century. Additional scenarios examined the …

Native Plants For Southeast Virginia Including Hampton Roads Region, Virginia Institute Of Marine Science – Center For Coastal Resources Management, Virginia Coastal Zone Management Program - Virginia Department Of Environmental Quality, Partner Organizations

Reports

This guide showcases the attractive variety of plants native to Southeast Virginia, which includes the Hampton Roads region. Native plant species have evolved within specific areas and been dispersed through their range without known human involvement. These plants form the primary structure of the living landscape and provide food and shelter for native animal species.

The Influence Of Environmental Factors And Resource Availability On Zostera Marina Flowering Intensity, Andrew J. Johnson

Dissertations, Theses, and Masters Projects

Sexual reproduction and the production of seeds are important for the resilience of all angiosperm species. For clonal species, such as the seagrass Zostera marina, resource allocation is complicated because these species reproduce both asexually and sexually, and the factors contributing to allocation to these two processes remains unknown. The goal of this study was, therefore, to investigate the importance of critical light, nutrient, and rhizome resources on Z.

marina sexual reproduction and flowering intensity. To evaluate the importance of sediment nutrients on Z. marina flowering intensity two distinct field manipulative experiments and one field survey were initiated: 1. Sediments …

The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley

Dissertations, Theses, and Masters Projects

Seed dispersal and seed predation are two important processes in the early life history of plants. The interaction between these two processes influences the population recruitment from a parent plant. These mechanisms have been studied extensively in terrestrial plants and have resulted in various models to describe plant recruitment (e.g. Janzen-Connell, Hubbell, McCanny). However, seed dispersal and predation may also influence the population recruitment of marine angiosperms, such as Zostera marina (eelgrass). The objectives of this study were to determine: 1.) the patterns of seed dispersal as a function of distance from the seed source, 2.) the predation pressure on …

The Fruits Of Their Labors: Exploring William Hamilton's Greenhouse Complex And The Rise Of American Botany In Early Federal Philadelphia, Sarah Jane Chesney

Dissertations, Theses, and Masters Projects

This dissertation explores the world of early American botany and the transatlantic community of botanical enthusiasts from the perspective of William Hamilton, gentleman botanical collector in late eighteenth and early nineteenth century Philadelphia. Drawing on both existing documentary sources and three seasons of archaeological excavation at The Woodlands, Hamilton's country estate on the west bank of the Schuylkill River, I analyze both the physical requirements of botanical collecting as well as the more nuanced social, cultural, and economic elements of this trade and its early modern participants.;The personal experiences of individual participants in this exchange are often traced through the …

The Effects Of Salinity Pulses Of Varying Duration And Intensity On Three Freshwater Submerged Aquatic Vegetation Species, Rebecca Wright

Dissertations, Theses, and Masters Projects

No abstract provided.

The Effects Of Seagrass Species And Trophic Interactions In Experimental Seagrass Communities, Althea F. P. Moore

Dissertations, Theses, and Masters Projects

No abstract provided.

Vascular Flora Of The Totuskey Creek Watershed, Richmond County, Virginia, Christopher W. Johnstone

Dissertations, Theses, and Masters Projects

No abstract provided.

Field Guide To Virginia Salt And Brackish Marsh Plants, Virginia Institute Of Marine Science, Center For Coastal Resources Management

Reports

No abstract provided.

Investigation Of Relationships Between Short-Term Photosynthetic Performance And Long-Term Growth Of Zostera Marina, Elizabeth Amy Lewis

Dissertations, Theses, and Masters Projects

No abstract provided.

Vegetation Dynamics Of A Tidal Freshwater Marsh: Long-Term And Inter-Annual Variability And Their Relationship To Salinity, Sarah B. Davies

Dissertations, Theses, and Masters Projects

No abstract provided.

Microevolutionary Processes In Chesapeake Bay (Virginia, Usa) Eelgrass, Zostera Marina L, Jennifer Michelle Rhode

Dissertations, Theses, and Masters Projects

Eelgrass (Zostera marina L.) is the northern hemisphere's dominant marine angiosperm, a species with both ecological and economic importance. Initial allozyme surveys of eelgrass populations in Chesapeake Bay (Virginia, USA) revealed substantial amounts of geographically-partitioned genetic variation, which could be the result of nonselective demographic processes, including founder events and drift. However, strong spatial variation in the environment and in eelgrass morphology suggests that differential adaptation of isolated beds to local environmental conditions could also produce these patterns. This dissertation used three sets of studies to investigate microevolutionary processes might produce the observed variation among Chesapeake eelgrass beds: (1) an …

Effects Of Light And Salinity Stress On Vallisneria Americana (Wild Celery), Gail T. French

Dissertations, Theses, and Masters Projects

No abstract provided.

Spatial And Temporal Variation In Plant Communities Of Three Tidal Salt Marshes Along The York River, Virginia, Rosemary E. Laird

Dissertations, Theses, and Masters Projects

No abstract provided.

An Introduction To Wetland Seed Banks, Douglas A. Deberry, James E. Perry, Virginia Institute Of Marine Science, Wetlands Program

Reports

No abstract provided.

Plant Species Of The Virginia Coastal Plain Flora That Are Disjunct From The Mountains: Their Distribution, Abundance And Substrate Selectivity, Leah E. Mcdonald

Dissertations, Theses, and Masters Projects

No abstract provided.

A Systematic Treatment Of Acacia Coulteri (Fabaceae, Mimosoideae) And Similar Species In The New World, Jennifer T. Jawad, David S. Seigler, John E. Ebinger

VIMS Articles

Detailed descriptions, habitat preferences, geographic ranges, and representative specimens are given for the 13 taxa of the Acacia coulteri group from Mexico, Central America, and the southwestern United States. These species form a distinct group within Acacia series Vulgares, lacking prickles and usually having persistent stipules. A principal components analysis (PCA) of vegetative and floral features shows that the specimens examined form discrete units in plots of the first three principal components. The groups established by PCA mostly coincide with previously described species. The taxa within this group are phenetically similar, sharing many morphological features. These data also suggest …

Ecological Dispersal Mechanisms, Reproductive Ecology, And The Importance Of Scale In Zostera Marina In Chesapeake Bay, Matthew C. Harwell

Dissertations, Theses, and Masters Projects

Previous knowledge of the seed ecology of the clonal seagrass Zostera marina L. (eelgrass) suggests that sexual reproduction is not very important to the population dynamics of eelgrass; however, researchers have hypothesized long-distance dispersal for nearly a century. From a bay-wide sampling effort, viable eelgrass seeds in the seed bank were found throughout most of the lower and middle Chesapeake Bay, but abundance of seeds was highly variable. Lower seed-bank densities were found in middle Chesapeake Bay, the region with slow recovery of eelgrass populations. From natural and artificially created eelgrass populations, regional environmental conditions were found to have a …

Increasing The Probability Of Success In Restored Forested Wetlands, Kirk J. Havens, Gene Silberhorn

Reports

This study investigated survival and growth of two distinct ecotypic populations, with varying tolerance to waterlogging, of four species, Taxodium distichum (L.) Richard, Carpinus caroliniana Walt., Quercus michauxii Nutt. and Quercus pagoda Raf. (Syn. Q.falcata var. pagodifolia Ell.).

Systematic And Population Genetic Analyses Of Northern Vs Southern Yellow Lady's Slippers (Cypripedium Parviflorum Vars Parviflorum, Pubescens, And Makasin): Inference From Isozyme And Morphological Data, Lisa Ellen Wallace

Dissertations, Theses, and Masters Projects

No abstract provided.

The Vascular Flora Of The Carrotoman River Watershed, Lancaster County, Virginia, Troy W. Weldy

Dissertations, Theses, and Masters Projects

No abstract provided.

Phylogenetic Implications Of Sporogenesis Ultrastructure In The Genus Bossiella (Corallinales, Rhodophyta), Kimberly Joy Karnas

Dissertations, Theses, and Masters Projects

No abstract provided.

An Ultra Structural Study Of Sporogenesis, Vegatative Morphology, And Host-Parasite Interactions In Choreonema Thuretii (Corallinales, Rhodophyta), Elizabeth Anne Lapointe

Dissertations, Theses, and Masters Projects

No abstract provided.

Measurement Of In Situ Eelgrass Community Metabolism In Standing And Flowing Waters: Methods And Models, William James Seufzer

Dissertations, Theses, and Masters Projects

No abstract provided.