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Population Ecology Of A Caribbean Epiphyte Trichocentrum Undulatum (Orchidaceae): Defining Habitat And The Effects Of Herbivory And Hurricanes At Its Peripheral And Core Range, Haydee Borrero

FIU Electronic Theses and Dissertations

Population ecology studies are central to species conservation. My dissertation focused on the Florida state-listed endangered orchid, Trichocentrum undulatum at its northern-most range in the Everglades National Park (ENP), Florida and multiple populations throughout its core range in Cuba. Through surveying populations of T. undulatum across this range from 2013-2021, I made a new reporting on the occurrence of a specialized insect herbivore, Melanagromyza miamensis in Cuba (Chapter 1). This flower-crippling herbivore was previously known only in the ENP. With this discovery I assess the intensity and impacts of this herbivore, as well as others on T. undulatum across the …

Evaluating Changes In Visible To Short-Wave Infrared Spectral Reflectance Of Arctic Mosses In Response To Experimental Drying To Find The Best Predictors Of Moisture Content, Steven L. Unger

FIU Electronic Theses and Dissertations

Mosses are a dominant understory component in the Arctic and because of sparse canopy cover, contribute to spectral signals used in remote sensing estimates of various ecologically important characteristics such as productivity, phenology, and vegetation mapping. However, little is known about their contributions to community level spectra or how moisture content influences those spectral signals. Unlike vascular plants, mosses cannot actively regulate moisture content and are highly susceptible to desiccation. Previous research has shown that moss reflectance is sensitive to tissue moisture content. Here, a lab-controlled drying experiment was conducted to identify the best spectral predictors of moisture content of …

Functional Strategies Of Tree Fine-Roots In Relation To The Soil Environment And Microbiome: Variaiton In Root Morphology, Tissue Chemistry And Physiology, James Aaron Hogan

FIU Electronic Theses and Dissertations

Tree root systems have evolved multidimensional functioning, specializing in water and nutrient acquisition via different strategies. Root functional strategies vary among tree species and are adapted to the abiotic and biotic soil environment. This dissertation explores how three facets of root system functional strategies – morphology and chemistry, biotic associations with fungi, and respiration rates – vary within and among tree species along environmental gradients. Chapter one examines how root system morphology varies with forest succession and soil environment in a tropical forest of Hainan, China, finding that root systems had larger diameters and fewer root tips in the younger …

Hydrology And Fire History Drive Patterns In Post-Fire Recovery In Everglades Wetland Ecosystem, Jenisha Oli

FIU Electronic Theses and Dissertations

Although fire-adapted ecosystems in Everglades require regular burning to maintain wetland ecosystems, land management and climate-change have altered natural fire-regime. Due to changes in climate and hydrology, historical fire-regimes may become irrelevant. To understand changing fire return intervals, I look at patterns in ecosystem recovery, where fast recovery is indicative of resilience and adaption with an objective of understanding post-fire recovery time in Everglades. I evaluated how post-fire recovery rates were influenced by hydrology and fire-history (1948-2019) by measuring changes in normalized difference vegetation index following fires that burned between 2005-2019 within Everglades. Hydrology had stronger effect on post-fire recovery …

How Weeds Affect Insects In Mango Cultivation Of South Florida, Blaire Kleiman

FIU Electronic Theses and Dissertations

The use of weeds as insectary plants is an emerging management tactic by agroecologists and entomologists to sustain beneficial insect species. Fallow lands have always been used by insects and are an important part of their diet in fragmented ecosystems. Weeds provide floral resources to beneficial insects such as pollinators, parasitoids, and predators and resources to keep them within a field in between crop flowering. Using weeds as a tool in tropical fruit production reliant on pollination like Mango (Mangifera indica) allows farmers to reduce herbicide use, increases the biodiversity of both plants and insects, and increases pollination of crops …

Taxonomy And Systematics Of Plumeria L. (Apocynaceae) In The Caribbean Islands, Nichole M. Tiernan

FIU Electronic Theses and Dissertations

Plumeria L. (Apocynaceae) is a genus of flowering trees and shrubs that are often cultivated in tropical gardens worldwide. The majority of its species occur in the Greater Antilles with many as single-island endemics. The only comprehensive revision for the genus was done by Robert E. Woodson Jr. (1937) who recognized only seven species and created a ‘Plumeria obtusa complex’ with a plethora of synonyms. The first study provides an overview of the Caribbean Island members of the genus with a focus on Plumeria filifolia Griseb., a thin-leaved species endemic to Cuba that is featured because of its incredible …

Invasion Ecology And Response To Fire Of The Nonnative Fern Lygodium Microphyllum In The South Florida Everglades, Nicole Sebesta

FIU Electronic Theses and Dissertations

Lygodium microphyllum (Old World Climbing Fern (OWCF)) is a climbing fern native to tropical and subtropical regions of Australia, Asia, and Africa. First introduced to Florida as an ornamental in the 1960s, the fern has become a serious invasive in numerous Florida habitats, severely degrading native herbaceous and woody vegetation and altering fire behavior. One area with the greatest increase in OWCF cover is the sawgrass marsh of southern Everglades National Park (ENP), where prescribed fire is used for both maintenance of sawgrass marshes and management of OWCF infestations. However, the efficacy of OWCF control using fire in this habitat …

Evaluation Of Harvesting Time For Industrial Hemp (Cannabis Sativa L,) Pilot Project Varieties Grown In South Florida, Jordan W. Prats

FIU Electronic Theses and Dissertations

A field study was conducted to observe the natural development of cannabinoids in three daylength sensitive industrial hemp varieties Bubba Kush (BK), Emerald Flower (EF), and Golden Sunset (GS). Plants were configured in a randomized block design with 3 replications. Once 50% of the plants within a variety reached reproductive growth, plants were sampled weekly until senescence and analyzed through a HPLC-UV/DAD. The results from the study indicate that all three varieties of industrial hemp tested in field study reached reproductive growth within the first week of transplanting. This is due to a 12-hour day-length at the time and the …

Developing Sustainable Soil Building Strategies For Tropical Fruit Groves Within The South Florida Redland, Ariel Freidenreich

FIU Electronic Theses and Dissertations

Tropical fruit production has become a lucrative industry in Miami-Dade County. Consequently, developing sustainable farming practices to be applied to these systems to ensure healthy soils and economically viable fruit production is becoming increasingly important. The study is focused on the incorporation of cover cropping as a management strategy for perennial tropical fruit production and its applications for local growers. Cover crops are plants that are grown to cover soil to reduce erosion, increase soil fertility, and enhance farmland biodiversity. The project was specifically designed to test the impacts of highly prolific legumes sunn hemp (Crotalaria juncea) and …

Growth Of Diatom Fistulifera Alcalina In Bacterial Co-Culture And Comparative Mitogenomics Of Fistulifera Species, Erwin David Berthold

FIU Electronic Theses and Dissertations

Diatoms are excellent biological models of growth and intracellular oil generation. The productivity and compounds of diatoms, especially oils, support aquatic food chains and human medical and industrial needs. The qualities that made diatoms prolific producers, specifically diatom physiological features such as growth rates with intracellular lipid storage in alkaline environments, are however poorly understood. Another physiological aspect that remains unexplored is the effects of bacteria on the growth and lipid production of alkaliphilic diatoms. More studies, especially co-cultures, are needed for advances in diatom biology and strain performance for the algal biotechnological field. Besides physiology, diatom genetics using next-generation …

Production And Characterization Of Twelve Different Biochars And Evaluating Their Effects On Soil Health And Plant Growth, Shagufta Gaffar

FIU Electronic Theses and Dissertations

Biochar has been a topic of growing interest in the scientific community. It is a product derived from carbon rich organic materials through the process of pyrolysis. It has received wide attention as a means to improve soil fertility and crop productivity, absorb pollutants in soil, and sequester carbon to mitigate climate change. Recent research on biochar explores its impacts on the environment with particular focus on use as a soil amendment in agriculture. Biochar produced from different biomass and under different production process effects the environmental and agronomic impacts of its application in different ways. This means biochar can …

Systematic Studies In Myrtaceae Of The Greater And Lesser Antilles, Jonathan A. Flickinger

FIU Electronic Theses and Dissertations

The Myrtaceae, or myrtle family, are a group of flowering trees and shrubs represented in the Americas by over 2000 species of the predominantly Neotropical tribe Myrteae. Recent progress on the challenging systematics of the group has been achieved through molecular phylogenetics, but few of the almost 500 species endemic to the islands of the Greater and Lesser Antilles in the Caribbean have been included in either phylogenetic or revisionary studies. The purpose of my dissertation is therefore to contribute to the description and phylogenetic classification of Antillean Myrtaceae. The first study describes Eugenia walkerae, a new species of …

Influence Of Vermicompost Tea On Secondary Metabolites In Solanum Lycopersicum Within South Florida, Daphne K. Sugino Souffront

FIU Electronic Theses and Dissertations

Fresh Market Tomatoes provide a high revenue stream for Florida’s agricultural sector. To attain profitable yields, farmers introduce high inputs of pesticides to suppress pest invasion/damage. Heavy usage of pesticides has adverse effects on human and environmental health. A possible solution might be the incorporation of vermicompost in pest management. Typically used as a fertilizer, vermicompost has pest suppressant properties. Mechanisms influencing enhanced pest resistance are unknown. To identify such mechanisms, a study was conducted to evaluate physical and chemical changes of the BHN589 tomato plant following the addition of varying vermicompost tea treatments (T5%, T10%, and T20%) . Results …

Evolutionary Genetics Of The Genus Zamia (Zamiaceae, Cycadales), Michael Calonje

FIU Electronic Theses and Dissertations

The genus Zamia L. (Zamiaceae), consisting of 77 species, is the most species-rich and widely distributed cycad genus in the New World and is arguably the most morphologically and ecologically diverse genus in the Cycadales. We utilized a multilocus sequence dataset of 10 independent loci (9 single copy nuclear genes + 1 plastid) and extensive taxon sampling (over 90% of species) to infer phylogenetic relationships within Zamia. We infer a robust phylogenetic tree for the genus with a strong geographic delimitation of clades and find that four morphological characters typically used for diagnostic purposes in the genus exhibit a high …

Exploring The Potential Of Endophytes And Medicinal Plants As Sources Of Antimicrobials To Control Citrus Greening, Jessica Dominguez

FIU Electronic Theses and Dissertations

Citrus greening is an economically disastrous bacterial disease that infects all species of citrus, and currently has no cure. It is caused by Candidatus Liberibacter asiaticus (CLas), an unculturable phloem-limited bacteria vectored by the sap-sucking insect Diaphorina citri. Citrus greening has spread to every citrus-producing county in Florida; thus, there is a crucial need to develop environmentally safe treatments to reduce or eliminate CLas. It was hypothesized that endophytic microorganisms isolated from survivor citrus trees would show antagonistic activity against CLas; also, that plant extracts with known antimicrobial properties could suppress CLas. Oregano, thyme and turmeric extracts in the …

Inoculating Rhizobium And Arbuscular Mycorrhizal Fungi On Snap Bean Under Salinity Stress To Study Plant Growth And Glomalin Production Effects, Claudia Lyl Garcia

FIU Electronic Theses and Dissertations

Groundwater salinization from saltwater intrusion threatens Southeastern Florida’s commercially important snap bean (Phaseolus vulgaris) production because of the crop’s low salt-tolerance threshold. The present study was carried out to determine if co-inoculating salt-stressed snap beans with beneficial microbial symbionts (i.e., Rhizobium and arbuscular mycorrhizal fungi) can mitigate growth reductions. Additionally, the study also assessed whether co-inoculation had an effect on the production of glomalin, a protein secreted by arbuscular mycorrhizal fungi that improves soil aggregation. Snap beans were inoculated (-AMF/-Rhizobium, +AMF/-Rhizobium, +AMF/+Rhizobium) and irrigated with varying salinity levels (0.6, 1.0, 2.0 dS …

Factors Affecting Green Turtle Foraging Ecology Across Multiple Spatial Scales, Elizabeth Rose Whitman

FIU Electronic Theses and Dissertations

The hierarchical levels at which resource selection occurs can have important consequences for individual and population energy budgets and structure the impacts of a forager on its ecosystem. Assessing factors affecting resource selection of large marine herbivores across scales is important because of their potentially large impacts on seagrass community dynamics and historical and current changes in their population sizes and those of their potential predators. I explored the factors (predation risk, resource abundance, quality and identity) affecting resource use of large marine herbivores (green turtles, Chelonia mydas) from the scale of habitat patches to forage species within patches. …

The Evolution And Domestication Genetics Of The Mango Genus, Mangifera (Anacardiaceae), Emily Warschefsky

FIU Electronic Theses and Dissertations

Domesticated species are vital to global food security and have also been foundational to the formulation and advancement of evolutionary theory. My dissertation employs emerging molecular genomic tools to provide an evolutionary context for crop improvement. I begin by providing a contemporary perspective on two components of domestication biology that have long been used to improve crop production: wild relatives of crop species and grafted rootstocks. First, I propose a method to systematically introgress crop wild relative diversity into crop breeding programs. Then, I explore rootstocks, the lesser-known half of the perennial crop equation, documenting prevalence and diversity, cataloging rootstock …

Drivers And Mechanisms Of Peat Collapse In Coastal Wetlands, Benjamin J. Wilson

FIU Electronic Theses and Dissertations

Coastal wetlands store immense amounts of carbon (C) in vegetation and sediments, but this store of C is under threat from climate change. Accelerated sea level rise (SLR), which leads to saltwater intrusion, and more frequent periods of droughts will both impact biogeochemical cycling in wetlands. Coastal peat marshes are especially susceptible to saltwater intrusion and changes in water depth, but little is known about how exposure to salinity affects organic matter accumulation and peat stability. I investigated freshwater and brackish marsh responses to elevated salinity, greater inundation, drought, and increased nutrient loading. Elevated salinity pulses in a brackish marsh …

Top-Down And Bottom-Up Approaches To Understanding The Fate Of The Federally Endangered Schaus’ Swallowtail Butterfly (Heraclides Aristodemus Ponceanus), Jaeson T. Clayborn

FIU Electronic Theses and Dissertations

The federally endangered Schaus’ swallowtail butterfly (Heraclides aristodemus ponceanus) populations have declined precipitously over the years. Despite tremendous efforts to augment the numbers of this butterfly through captive-bred releases and habitat enhancements, it remains imperiled and federally endangered. The dissertation’s objectives were: 1) to restore dry forest habitat in Biscayne National Park (BNP) for Schaus’ swallowtails; 2) to assess host plant (torchwood and wild lime) survivorship and growth in the restoration sites (BNP) and project dry forest habitat loss because of imminent sea level rise (SLR); 3) to quantify ant activity and record predator-prey interactions against Heraclides caterpillars …

A Historical Floristic Inventory Of Pine Rockland Fabaceae (Leguminosae), Adel L. Pena

FIU Electronic Theses and Dissertations

The objectives of this study were to investigate temporal changes in the diversity of pine rockland Fabaceae, induced by anthropogenic factors. Herbarium collections spanning 170 years were used to analyze species frequency and richness. The results indicated temporal fluctuations in diversity with frequency of native species highest previous to the year 1920, and exotic-invasive species richness peaking after the 1960s. The accompanying species list resulting from the inventory included 122 Fabaceae species, in 56 genera, with an additional 19 species not previously listed for pine rocklands. The results emphasize the damage caused by early and deliberate introductions of exotic species, …

Laurel Wilt Disease: Early Detection Through Canine Olfaction And "Omics" Insights Into Disease Progression, Julian L. Mendel

FIU Electronic Theses and Dissertations

Laurel wilt disease is a vascular wilt affecting the xylem and water conductivity in trees belonging to the family Lauraceae. The disease was introduced by an invasive species of ambrosia beetle, Xyleborus glabratus. The beetle, together with its newly described fungal symbiont Raffaelea lauricola (pathogenic to host trees), has lead to the devastation and destruction of over 300 million wild redbay trees in southeastern forests. Ambrosia beetles make up a very unique clade of beetle and share a co-evolved obligatory mutualistic relationship with their partner fungi. Rather than consuming host tree material, the beetles excavate galleries or canals …

A Floristic Study Of Halmahera, Indonesia Focusing On Palms (Arecaceae) And Their Seed Dispersal, Melissa E. Abdo

FIU Electronic Theses and Dissertations

The dispersal services of frugivores affect plant community assembly, persistence, and gene flow in the short-term, and in the long-term are critical to ensuring that tropical trees and palms can regenerate in disturbed areas and can migrate amidst climate change. Halmahera is the largest Moluccan island within the Wallacea biodiversity hotspot, yet data on its plant and animal distributions and interactions are almost null. I studied the tropical trees and palms of Halmahera and their seed dispersal dynamics. Chapter I explores the palms of the Moluccan islands through field-, herbarium-, and literature- based studies. The results of herbarium specimen collections …

Morphology, Architecture And Growth Of A Clonal Palm, Acoelorrhaphe Wrightii, Sara M. Edelman

FIU Electronic Theses and Dissertations

Palms provide valuable commercial resources in the tropics and are dominant species in tropical lowland forests. While general biology of palms is well studied, there are gaps in the literature on palm growth through life stages and in response to environmental conditions. Literature gaps on palm growth could be caused by the slow growth of palms; it is difficult to monitor morphology and architecture for the periods of time necessary to capture changes. Acoelorrhaphe wrightii is a threatened palm native to southern Florida with an unusual adult architecture. The purpose of this dissertation was to study growth A. wrightii throughout …

A Framework For Assessing Alternative Agro-Ecosystems: Finding Multi-Functional Solutions For Sustainable Urban Landscapes., Thais H. Thiesen Ms.

FIU Electronic Theses and Dissertations

Creating sustainable urban landscapes in light of growing population pressures requires interdisciplinary multi-functional solutions. Alternative agro-ecosystems described as food forests, permaculture gardens, and/or edible landscapes among others could offer potential ways to address the social, economic and ecological goals of various stakeholders simultaneously. The present research used a unique rubric, the Permaculture and Agro-ecosystems Sustainability Scorecard (PASS) that combines existing agricultural and landscape sustainability indicators in order to assess alternative agro-ecosystems. The rubric evaluates provisioning, regulating, supporting and cultural ecosystem services such as pollinator presence, biodiversity, pesticides and fertilizer use, carbon sequestration and human interactions. The PASS was used to …

Screening Of Plants For Antibacterial Properties: Growth Inhibition Of Staphylococcus Aureus By Artemisia Tridentata, Steven Ross Eichelbaum

FIU Electronic Theses and Dissertations

Drug-resistant pathogenic and opportunistic bacteria are increasing in occurrence and prevalence, and pose a dangerous threat to human health. In the search for novel antibiotics with which to combat this threat, plants, specifically those used in traditional medicine with ascribed antibacterial properties, offer a promising and potentially vast source of such therapeutic compounds. The purpose of this study was therefore to screen chemical extracts created from various plant species for antibacterial properties versus pathogenic bacterial species. In the course of these antibacterial assays, we successfully identified a methanol extract derived from Artemisia tridentata tridentata plant material as capable of inhibiting …

Medicinal Plants Of Trinidad And Tobago: Selection Of Antidiabetic Remedies, Angelle L. Bullard-Roberts

FIU Electronic Theses and Dissertations

Diabetes mellitus (DM) is a group of non-infectious diseases that cause hyperglycemia. DM symptoms were first clinically described by ancient Greek physicians whose prescriptions included plant-based remedies. Today, DM affects >400 million people globally and prevalence rates are rapidly increasing in developing countries where basic healthcare relies on local knowledge of botanical remedies. Many developing countries are home to diverse peoples and plants—providing fodder for varied plant-selection strategies and unique botanical pharmacopoeias.

I addressed the plant-selection strategies used in a multi-ethnic, developing country, Trinidad and Tobago (T&T), to ascertain their role in shaping the local antidiabetic pharmacopoeia and to assess …

Effects Of Host-Plant Density On Herbivores And Their Parasitoids: A Field Experiment With A Native Perennial Legume, Andrea Salas

FIU Electronic Theses and Dissertations

Senna mexicana chapmanii (Fabaceae: Caesalpinoideae), an attractive and threatened species native to pine rocklands of southern Florida, is consumed by folivorous caterpillars of Sulfur butterflies (Lepidoptera: Pieridae). Caterpillars may be deterred or eaten by predators, but also very important are parasitoids, both flies and wasps. This study investigated the effects of plant density on Sulfur caterpillar numbers and rates of parasitization.

Senna mexicana chapmanii plantations were established at agricultural and urban areas; both sites are adjacent to protected pine rockland areas. Sulfur butterfly immature stages were collected and reared to glean information regarding number of herbivores and rates of parasitization. …

Pesticides And Pollination Of Imperiled Plants Of The Lower Florida Keys, Brittany M. Harris

FIU Electronic Theses and Dissertations

Degraded pollinator habitat may have far-reaching consequences for recovery of imperiled flowering plant populations. Studies indicate that broad-spectrum insecticides used in mosquito abatement are detrimental to non-target invertebrates, including pollinators. A decline in efficient pollinators can reduce plant fitness by decreasing reproductive output and constraining genetic diversity, a challenge for rare plants.

In 2015, I monitored flower visitation and fruit set of three imperiled plant species throughout protected areas on three islands in The Lower Florida Keys. These islands consist of conservation land fragmented by intermittently dispersed residential neighborhoods that seasonally spray insecticides for mosquito control. Flowers open at treatment …

Comparison Of Synthetic Versus Organic Herbicides/Insecticides On Arbuscular Mycorrhizal Fungi In Abelmoschus Esculentus, Ariel Freidenreich

FIU Electronic Theses and Dissertations

Arbuscular mycorrhizal fungi (AMF) play a crucial role in improving the growth of a vast majority of plants. Past researchers have discovered that agricultural practices have a significant negative effect on the diversity of AMF. Arbuscular mycorrhizal fungi are reported to enhance plant nutrient uptake, stress tolerance, and soil aggregate formation which are key aspects of productive low-input farming. The objective of this study was to investigate the effects of four pesticides on the ability of AMF to colonize the roots of okra plants (Abelmoschus esculentus). The pesticides being tested include two synthetic chemicals (glyphosate and carbaryl) and …