Digital Commons Network^™

Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown

Dissertations, Theses, and Capstone Projects

This dissertation examined the seasonal freeze/thaw activity in boreal-Arctic soils and vegetation physiology in Alaska, USA and Alberta, Canada, using in situ environmental measurements and passive microwave satellite observations. The boreal-Arctic high-latitudes have been experiencing ecosystem changes more rapidly in comparison to the rest of Earth due to the presently warming climatic conditions having a magnified effect over Polar Regions. Currently, the boreal-Arctic is a carbon sink; however, recent studies indicate a shift over the next century to become a carbon source. High-latitude vegetation and cold soil dynamics are influenced by climatic shifts and are largely responsible for the regions …

Csi Botany: Dna Barcode “Fingerprints” Identify Cryptic Urban Flora, Luis R. Vega

Theses

As short genomic markers, DNA barcodes can play a role in conservation by identifying cryptic species and hybrids when morphological approaches fall short. Here we present our application of barcodes to the identities of two wetland taxa as part of an ongoing floristic inventory of Van Cortlandt Park (VCP), Bronx, NY. Previous barcode data by Marriott et al. (2018) identified the VCP lake water lily as the exotic Nymphaea alba, rather than the native N. odorata as historically described. In addition, cattails in the park were historically identified as the native Typha latifolia and the exotic T. angustifolia …

Conservation, Comparative Genomics And Species Delimitation Of The Reindeer Lichens (Cladonia), Jordan R. Hoffman

Dissertations, Theses, and Capstone Projects

The genus Cladonia represents one of the most speciose genera of lichenized fungi, with more than 500 known species encompassing a diverse array of morphologies and habits. These lichens form keystone species in many habitats, serving a variety of ecological roles. However, despite being among of the more well studied lichens, there is much still unknown or under-studied about them. As is the case with most lichen study systems, phylogenetic study has been limited to a small number of partial loci, while adoption of next-generation sequence methods has been slow. As a consequence, there are still knowledge gaps in Cladonia …

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 …

Evolution And Development Of The Seed Coat In Gymnosperms, Cecilia Zumajo

Dissertations, Theses, and Capstone Projects

Gymnosperms and angiosperms are the most abundant plant lineages on earth and constitute a turning point in the evolution of plants because they are at the origin of the seed, a key morphological and developmental novelty in the evolution of land plant. Although the morphological variation of the seed, across seed plants, may on its own, explain the complexity of this structure, the origin, and evolution are even more, the understanding of these topics is still under discussion. Evidence shows that previous studies have often lacked the component of gene expression, particularly in species that are not model species. The …

Some (Im)Material Girls, Living In (Im)Material Worlds, With Seeds, Stars, And Shit, Matthew Weiderspon

Theses and Dissertations

This writing situates material and gestural vocabularies cultivated in my artwork in relation to my lived experience; primarily my rural upbringing in Colorado. Scattered floor dispersals, calling sounds, and bodily movements desire reconsiderations of hope in precarity through a disorientation of place, association, scale, and language.

Chloroplast Genome Evolution In The Klebsormidiophyceae And Streptofilum, Sarah Glass

Theses

The Klebsormidiophyceae are a class of green microalgae found globally in both freshwater and terrestrial habitats. Morphology-based classification schemes of this class have been shown to be insufficient, particularly due to the simple morphology of these algae, the tendency of morphology to vary in culture versus in field conditions, and rampant morphological homoplasy. Molecular studies revealing cryptic diversity have renewed interest in this group. We sequenced the complete chloroplast genomes of taxa in the Klebsormidiophyceae representing the known taxonomic breadth of this class, as well as the chloroplast genomes of three strains of Streptofilum, a recently discovered algal lineage …

Method Development For Identifying Counterfeit Cigarettes Using Environmental Pollen Analysis, Tiffany Chan

Student Theses

Cigarette counterfeiting negatively impacts government revenue and undermines tobacco control policies. Tracking geographical origins and potential trade routes of counterfeit cigarettes is important for investigation illegal trade in tobacco products. Traditional pollen extraction techniques provide clear residues of pollen trapped on tobacco leaves and used for geographical identification; however, such methods are time-consuming and utilize concentrated chemicals. This study developed a simple, fast and environmentally friendly method for extraction of pollen grains used in differentiating genuine and counterfeit cigarettes. Experimental factors that may affect pollen recovery including number of cigarettes, extraction solution, and extraction temperature, were optimized. The optimum parameters …

Systematics And Ecology Of The Andean Neotropical Schefflera (Araliaceae) With Globose Capitate Inflorescences And Use Of Niche Modeling For Iucn Red List Threat Assessment Of Plerandra Elegantissima (Araliaceae), Carlos V. Rodrigues

Dissertations, Theses, and Capstone Projects

Since the end of the 19^thcentury, ScheffleraJ.R. Forst. & G. Forst.has been recognized as the largest and most wide-ranging genus of Araliaceae. It can be found throughout the humid tropics and subtropics, is not particularly diverse at low elevations in the warmest regions, and a few taxa extend into warm-temperate areas. As currently circumscribed, the genus contains 605 described species and many hundreds more awaiting formal description. However, a succession of phylogenetic studies have confirmed that Schefflera, as currently circumscribed,is polyphyletic, comprising five geographically centered lineages scattered across the phylogenetic tree of Araliaceae, and …

Systematics Of Carex Section Laxiflorae (Cyperaceae), Jenna Dorey

Dissertations, Theses, and Capstone Projects

Carex, with more than 2100 species, is the most species-rich genus of flowering plants in temperate regions of the world. Members of the family Cyperaceae are colloquially known as sedges, and members of the genus Carex are called “true sedges.” Carex occur on every continent except for Antarctica, they thrive in a panoply of habitats, and are ecologically important as a forage source for wildlife, carbon sequestration, prevention of soil erosion, and providing habitat for fresh water invertebrates. Despite their importance many sedges are still poorly known, such as the woodland sedges in Carex section Laxiflorae, which is …

Distribution And Population Structure Of The Invasive Nitellopsis Obtusa (Desv. In Loisel.) J. Groves And Native Species Of Characeae In The Northeast U.S.A., Robin Sleith

Dissertations, Theses, and Capstone Projects

Freshwater ecosystems are some of the most biologically diverse environments on Earth. Billions of humans rely on functioning freshwater ecosystems for drinking water and many other services. These ecosystems are increasingly threatened by human impacts including nutrient pollution, invasive species, and climate change. Here I contribute four research chapters that investigate freshwater diversity and ecosystem threats using the Characeae, a family of freshwater green macroalgae, as a study system. Characeae are a diverse and ancient group with more than 500 extant species and a fossil history spanning at least 250 million years. These algae are macrophytes in freshwater ecosystems, and …

A Contribution Toward A Global Monograph Of Gyroporus: Taxonomy, Phylogeny, Biogeography, Naveed Davoodian

Dissertations, Theses, and Capstone Projects

Gyroporus (Sclerodermatineae, Boletales, Agaricomycetes, Basidiomycota, Fungi) is a genus of ectomycorrhizal mushroom-forming fungi distributed throughout the world in suitable habitats. Previous attempts to untangle the diversity of this genus proved difficult due to the presence of semi-cryptic species and equivocal results from phylogenetic analysis of ribosomal RNA markers. To overcome these obstacles, a combined taxonomic and phylogenetic (emphasizing protein-coding genes) approach is used here to delimit species and elucidate geographic and evolutionary patterns of Gyroporus. Careful study of relevant literature and herbarium specimens was augmented by field work in North America, Australia, and East Asia for observation and collection …

Binding Of Maize Necrotic Streak Virus (Mnesv) 3’ I-Shaped Structure (3’ Iss) To Eukaryotic Translation Factors (Eifs) And Implication In Eif4f Mediated Translation Initiation, Qiao Liu

Dissertations, Theses, and Capstone Projects

5' m⁷GpppN cap and the 3' poly adenosine (A) tail of eukaryotic mRNAs are key elements for recruiting translation initiation machinery in canonical translation initiation. Unlike host mRNAs, many viruses lack these elements and yet they are translated efficiently. Plant viruses, in particular, have complex structures within their untranslated regions (UTR) that allow them to bypass some cellular translation control steps. In Maize necrotic streak virus (MNeSV) 3' UTR, an I-Shaped RNA Structure (ISS) has been reported to mediate the virus translation initiation progress. 3’ ISS binding with eIF4F has been shown to facilitate translation. 5’ -3’ kissing …

Anti-Proliferative Effects Of Garcinia Fruits In Breast Cancer Cells, Harini Anandhi Senthilkumar

Dissertations, Theses, and Capstone Projects

Breast cancer continues to be the second leading cause of death in women, even with the recent advances in research that has led to an improved understanding of molecular pathways and targets. Increasing mortality due to recurrence and lack of targeted drugs, especially in aggressive breast cancer subtypes such as triple negative breast cancer, has gained attention from the research community. With nearly 50% of the commonly used cancer drugs being sourced from plants, bioactive small molecules derived from a natural origin have immense potential as therapeutics. This study focuses on the anti-proliferative activities of benzophenones isolated from the edible …

The Therapeutic Potential Of Natural Products From Vaccinium Berries For Viral And Lung Diseases Through An Improved Lc-Ms-Based Chemometric Approach, Vanya I. Petrova

Dissertations, Theses, and Capstone Projects

Smoking is a global epidemic that creates serious health and economic burden. It is the primary, preventative factor for the majority of causes of death worldwide. Analysis of publicly available data revealed that smoking prevalence rates among the youth in developing countries, especially in Bulgaria, are alarmingly high. The Bulgarian population has one of the highest percentages of smokers and the second highest rate among teenage girls. Consequently, chronic diseases affected by smoking, such as chronic obstructive pulmonary disorder (COPD), have been increasing there in the last five years. Poland, on the other hand, is an exemplary outlier for the …

Evolution Of Floral Morphology And Symmetry In The Miconieae (Melastomataceae), Maria Gavrutenko

Dissertations and Theses

Analyses of evolution of floral morphology and symmetry broaden our understanding of the drivers of angiosperm diversification. Integrated within a flower, labile floral characters produce different phenotypes that promote variable interactions with pollinators. Thus, investigation of floral evolution may help infer potential historic transitions in pollinator modes and ecological pressures that generated present diversity. This study aims to explore morphological evolution of flowers in Miconieae, a species-rich Neotropical tribe within family Melastomataceae. Despite a constrained floral plan, Melastomataceae manage to achieve a variety of floral traits appealing to diverse pollinator types, with majority of the species requiring specialized “buzz pollination” …

Lichen Conservation In Eastern North America: Population Genomics, Climate Change, And Translocations, Jessica Allen

Dissertations, Theses, and Capstone Projects

Conservation biology is a scientific discipline that draws on methods from diverse fields to address specific conservation concerns and inform conservation actions. This field is overwhelmingly focused on charismatic animals and vascular plants, often ignoring other diverse and ecologically important groups. This trend is slowly changing in some ways; for example, increasing number of fungal species are being added to the IUCN Red-List. However, a strong taxonomic bias still exists. Here I contribute four research chapters to further the conservation of lichens, one group of frequently overlooked organisms. I address specific conservation concerns in eastern North America using modern methods. …

Are Weevils Picky Eaters? Community Structure And Host Specificity Of Neotropical Saproxylic Beetles (Coleoptera: Curculionidae), Jhunior A. Morillo

Dissertations and Theses

Abstract Primary saproxylic beetles play a major role in forest nutrient cycling and making deadwood accessible to other decomposers. Understanding beetle host preferences and patterns of community assembly is critical for their conservation, and for predicting which species might become invasive. This project aims to investigate the ecological and host specificity, as well as the community composition of curculionids in a mosaic of old-growth (OG) and secondary forest on the Osa Peninsula, Costa Rica. The subfamily Scolytinae was expected to be the most species-rich and abundant. Ambrosia beetles were expected to have more generalist species than other curculionids. Old growth …

Metabolic Profiling And Polymer Formation Of Gene Silenced Potato Periderms, Qing Cai

Dissertations, Theses, and Capstone Projects

Suberin is a biopolyester constituent of specialized plant periderm tissues formed within the phellem cell walls. Suberin and waxes of the periderm layer act to prevent water diffusion, mechanical breakdown and pathogenic invasion in plants. Ferulic esters, ω-hydroxyacids and α,ω-fatty diacids are considered to be the most important linkage between aliphatic and aromatic suberin domains and also linked with cell-wall polysaccharides. The potato gene FHT (fatty ω- hydroxyacid/fatty alcohol hydroxycinnamoyl transferase) esterifies ferulic acid to suberin. Diminished levels of feruloyl transferase activity have been associated with lowered amounts of feruloyl esters of fatty acids in both suberin-associated waxes and suberin …

Explorations In Advancing Microalgae Productivity, Peter Neofotis

Dissertations, Theses, and Capstone Projects

This thesis is part of an effort to advance microalgae cultivation for biofuel and high value products. The first chapters describe a large scale screening effort in which novel strains that hold great promise in large outdoor cultivation systems were isolated. Among these are strains of Scenedesmus obliquus, Borodinellopsis texensis, Chlorella sorokiniana, Ankistrodesmus, Coelastrella, and a previously uncharacterized species in the Chlamydomonadales. These species are characterized in terms of their phylogenetic relationship, biomass productivity, and, for some, lipid and carotenoid profiles under growth and stress conditions. Also discussed in regards to growth metabolism and oil …

Search For Host Factors Involved In Attachment Of Agrobacterium Tumefaciens To Plants, Anna Petrovicheva

Dissertations, Theses, and Capstone Projects

Agrobacterium tumefaciens is able to infect a diverse array of plants and causes crown gall disease. Typically these bacteria attach to plant roots and transform the plant cells to induce tumors. The mechanism of this attachment in the infection process is not yet fully understood. Using wild type Arabidopsis thaliana, Columbia-0, and several Arabidopsis mutant lines as a binding target, we screened for A. thaliana mutants with altered adhesion.

The A. thaliana mutant lines were selected in The Arabidopsis Information Resource (TAIR) according to possible location of the resulting protein and similarity to known transformation mutants. Of these mutants …

Systematics And Biogeography Of Orthaea Kloztsch (Ericaceae: Vaccinieae), Nelson Salinas

Dissertations, Theses, and Capstone Projects

In the first chapter a study of the distribution patterns of the neotropical Vaccinieae (Ericaceae) is presented. Five areas of endemism were recovered: Central America, northern Chocó, southern Chocó, eastern Ecuador, and Yungas. Divergence times estimations indicate that the Andean clade of Vaccinieae migrated to South America during the Late Oligocene or Early Miocene (28.9-17.84 MA), and most of the subsequent diversification took place during the Tertiary. The Yungas was the first Andean area to be colonized, and several dispersals towards the north expanded their distribution range. Both areas of endemism and dispersal events were influenced by geological processes, such …

Systematics And Evolution Of Leandra S.Str. (Melastomataceae, Miconieae), Marcelo Reginato

Dissertations, Theses, and Capstone Projects

Phylogenetic studies in the Melastomataceae have demonstrated the need of taxonomic rearrangements in the current classification. Melastomes are among the most diverse groups of plants and several cases of known artificial taxa are observed and awaiting further resolution. One example is the Leandra s.str. clade, which includes the majority of the taxa traditionally treated in the genus Leandra. Some attempts have been made to infer the relationships of Leandra s.str., but the sampling in these earlier studies was sparse and the resolution low inside the clade. The main objective here is to propose a comprehensive phylogenetic framework for this group …

Ethnomedical, Ecological And Phytochemical Studies Of The Palauan Flora, Christopher Kitalong

Dissertations, Theses, and Capstone Projects

There has been a serious deterioration of Palauan culture, language and traditional practices over the last century. To promote health and avoid this deterioration of tradition, ecological, ethnobotanical and phytochemical studies have been carried out on the plant Phaleria nisidai Kaneh. (Thymelaeaceae), "Delal a Kar", Palauan for "Mother of Medicine". This study is the first study that sets the foundations for the development of natural Palauan therapeutics, through validation of ethnomedically significant plants. Validations of these plants is done through documenting Palauan plant ethnomedical data; mapping the distribution of Palauan plants on limestone Rock Islands; and analyzing ethnopharmacological and phytochemical …

A Systematic Revision Of North American Tolypella A. Braun (Charophyceae, Charophyta), William Perez

Dissertations, Theses, and Capstone Projects

Charophyta comprises the algal classes Mesostigmatophyceae, Chlorokybophyceae, Klebsormidiophyceae, Coleochaetophyceae and Zygnematophyceae and the land plants. However, the precise phylogenetic position of these algal classes with respect to land plants is unresolved as are the phylogenetic relationships among genera in Charophyceae (Characeae). Characeae contains two tribes with six genera: tribe Chareae (Chara, Lamprothamnium, Lychnothamnus and Nitellopsis) and tribe Nitelleae (Nitella and Tolypella). Tolypella was considered the third most species-rich genus but, in the most comprehensive taxonomic treatment of Characeae, 16 Tolypella species were consolidated into two species, T. nidifica and T. intricata in sections Rothia …

An Ethnobotanical, Ecological And Lc-Ms-Based Chemometric Investigation Of Phaleria Nisidai, A Traditional Adaptogen Containing Diterpene Esters From Palau, Micronesia, Daniel Kulakowski

Dissertations, Theses, and Capstone Projects

An ethnobotanical, ecological and LC-MS-based chemometric investigation of Phaleria nisidai, a traditional adaptogen containing diterpene esters from Palau, Micronesia

Palau is a country with a rich heritage of traditional medicine still being practiced. One of the most popular and respected remedies in Palau is a tea made from fresh leaves of Phaleria nisidai Kaneh. (Thymelaeaceae). Interviews conducted to determine the use of this plant revealed that it is employed non-specifically to treat a variety of general health concerns. Its use as a prophylactic to keep away sickness, as a 'system cleaner', as well as for strength and energy indicate …

Phylogeny And Population Genetics Of The Endangered Dwarf Bear-Poppy, Arctomecon Humilis Coville (Papaveraceae) Using Microsatellite Markers, Joshua Simpson

Dissertations, Theses, and Capstone Projects

The genus Arctomecon (Papaveraceae) is comprised of three narrowly endemic rare species that are largely restricted to gypsum soils of the eastern Mojave Desert. The small, remaining populations of these species have become increasingly isolated by urban development and habitat fragmentation. Arctomecon humilis is federally listed as endangered due to its limited distribution within a ~15 km radius of an actively expanding city. Organizations involved with land management and conservation have called for greater insight into the genetic variation and population structure of the remaining subpopulations as they make important decisions regarding where to focus their efforts and resources.

The …