Botany Commons^™

Investigation Into Mycorrhizae Associated With Native Venus' Flytrap Root Tissue, Anna Carnaggio

Electronic Theses and Dissertations

Dionaea muscipula, a plant commonly known as the Venus' flytrap, is found native to the southeast corner of North Carolina and the northeast corner of South Carolina. Several populations of native Venus' flytraps are known to exist in the nutrient-poor peat bog conditions in and around Lewis Ocean Bay Heritage Preserve (LOBHP) in Northeastern South Carolina. Anthropogenic pressures in Horry County, specifically surrounding LOBHP, have resulted in a loss of habitat for several native and endangered species. As a result, conservation efforts are focused on relocating native Venus' flytraps into adjacent habitats to ensure survival. This is only a temporary …

Elevation And Population Size Effects On The Survival Of Drosera Rotundifolia, Jessica Williams

Electronic Theses and Dissertations

Carnivorous plants face significant conservation challenges due to habitat destruction, climate change, and illegal harvesting. This study explores how elevation and population size influence key-life history traits of D. rotundifolia, such as flowering phenology, prey capture efficiency, seed production, and germination rates. Higher elevations and larger populations are associated with extended flowering durations and increased prey capture. However, seed production and germination rates show complex patterns that are likely influenced by genetic diversity, resource availability, or environmental conditions. These insights inform targeted conservation strategies, emphasizing habitat preservation, enhancing prey availability, and maintaining genetic diversity. Public education and community engagement …

Monarch Butterfly (Danaus Plexippus) Oviposition Preferences And A Survey Of Fungal Pathogens On Native Milkweeds (Asclepias) Of The Northern Great Plains, Grace Damiano

Electronic Theses and Dissertations

North American monarch butterfly (Danaus plexippus) populations are experiencing significant declines due to habitat loss caused by land use changes. Much of the American Midwest where milkweed, the only host plant of the monarch butterfly, was once much more abundant has been converted to a predominantly agricultural landscape. There are nineteen species of milkweed native to the northern Great Plains region occupied by South Dakota, North Dakota, and Minnesota. Some of these milkweed species may be preferable to monarch butterflies for different reasons, including morphological factors such as stem length, species-level chemical factors, and temporal factors. As monarch …

Impacts Of Urbanization On Pollination Success For Common Milkweed (Asclepias Syriaca), David Rockow

Electronic Theses and Dissertations

Urbanization is among the greatest threats to biodiversity on the planet, and is projected to increase in magnitude in coming years. This growing threat makes it important to better understand how urbanization may impact vital ecosystem services, such as pollination. Studies on the impact of urbanization on pollination vary wildly in their findings. This study analyzed multiple aspects of pollination success in common milkweed populations varying in urbanization level, including insect community composition, pollen removal/deposition, and fruit/seed production. By analyzing multiple pollination aspects we can determine the overall mechanism in which urbanization instills on the entire pollination process. Overall, urbanization …

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …

Flora Of Doe Mountain Recreation Area, Johnson County, Tennessee, Benjamin Mccullough

Electronic Theses and Dissertations

A botanical inventory of Doe Mountain Recreation Area (DMRA) in northeastern Tennessee was conducted to help guide conservation-based management. A total of 484 species were found in DMRA, comprising 94 families, and 285 genera, 10 species listed in the state rare plant list, and 76 exotic species. Two species, Liatris virgata and Lycopodiella inundata, were new state records. Water in the Lycopodiella seep was an order of magnitude more acid than at other sites. An analysis of the wildland-urban interface showed that only 13% of the area was classified as uninhabited. The inventory-invasion index, introduced to quantify the relative …

Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson

Electronic Theses and Dissertations

Increasing evidence documenting the decline of insect populations, resulting from increasing human disturbances has resulted in efforts to establish pollinator gardens to provide additional resources for insect populations. However, our understanding of biotic and abiotic garden characteristics important for attracting and sustaining pollinator diversity is limited. Here, we evaluated 17 pollinator gardens to evaluate the effect of five biotic and three abiotic garden characteristics on pollinator species richness, abundance, and proportional representation of four pollinator functional groups. Plant species richness positively influenced pollinator richness and negatively influenced flower visitation. Bombus proportional abundance responded to several variables (distance to vegetation, plant …

Characterizing Patterns In Texas Gulf Coast Beach Dune Plant Species Composition, Cody Foster

Electronic Theses and Dissertations

Regional vegetation patterns of Texas beach plant communities were analyzed using cluster analysis, ANOSIM, SIMPER, NMDS, and ISA for fives zones representing the foredune complex of twenty Gulf Coast beaches. ANOVA revealed that zones differ in terms of percent bare sand, percent vegetative cover, and species richness. Cluster Analysis, ANOSIM, and SIMPER results indicate that Texas beaches can be divided into northern and southern regions based on differences in species composition of plant communities. Indicator Species Analysis (ISA) indicates that northern beaches are characterized by the presence of Rayjacksonia phyllocephala, Ambrosia Strophostyles, Ambrosia psilostachya, and Panicum amarum …

Reverse Genetic Analysis Of Ehd1 For An Association Between Flowering Time And Seed Dormancy In Rice (Oryza Sativa L.), Yeter Karakoc

Electronic Theses and Dissertations

This research aimed to understand the evolutionary mechanism of seed dormancy and flowering time and to provide basic knowledge for the manipulation of germination features in crop breeding. Flowering time and seed dormancy are two adaptive traits for flowering plants. Seed dormancy (SD) helps regulate the timing of germination to promote the survival of seed-bearing plants in adverse environments. Cereal crops and weedy/wild relatives, such as Asian cultivated rice and weedy rice (Oryza sativa L.), have weak and strong seed dormancy, respectively. Thus, weedy and cultivated rice has been used as a model system to investigate mechanisms of seed dormancy …

Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey

Electronic Theses and Dissertations

Increased nutrient availability has been widely linked to the success of invasive plants, however a general mechanism explaining these observations is lacking. Stoichiometric homeostasis (H), which is the regulation of internal nutrient concentrations, has been used to explain changes in plant community diversity under alterations in nutrient availability. One hypothesis holds that plants with high regulation (larger H) decrease in abundance in nutrient enriched conditions but are stable in nutrient deficient and drought conditions, likely due to extensive root systems. Additionally, plants with low regulation (lower H) increase in abundance under nutrient enriched conditions but are sensitive to drought …

Sunflower Pollinators In South Dakota: An Evaluation Of Species Composition, Abundance And Influence On Yield, Mackenzie Mattern

Electronic Theses and Dissertations

In 2017 and 2018, South Dakota was the largest producer of sunflowers, Helianthus annuus L. (Asterales: Asteraceae) in the US, grossing approximately $178 million per year. In South Dakota, both confection and oilseed sunflower cultivars are grown. Despite breeding efforts to increase sunflower's ability to self-pollinate there is evidence that pollinator visitation results in increased sunflower yields. In addition, there is evidence that sunflower pollen is beneficial for pathogen resistance in various bee species, suggesting the importance of a mutualistic relationship between pollinators and sunflowers. In some areas, observed increases in sunflower yield is attributed to the presence of Apis …

Soil Ecology Of The Exotic Dune Grass Leymus Arenarius., Matthew L. Reid

Electronic Theses and Dissertations

Exotic plants can alter the structure and function of native communities both above- and belowground, which is particularly important in primary successional sand dune ecosystems where plant-soil interactions are critical drivers of successional dynamics. In Great Lakes sand dunes, the native foundation grass Ammophila breviligulata dominates early in succession until an accumulation of detrimental soil organisms causes its die-back of the grasses. Die-back of this native foundation species can be slowed by mutualistic interactions between plants and mycorrhizal fungi. Changes to the plant community resulting from invasion, and subsequent effects on the soil community have the potential to disrupt the …

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens

Electronic Theses and Dissertations

Phenotypic plasticity, the ability of an individual to alter its growth in response to environmental conditions, is an attribute that is considered a likely invader attribute, as it provides the opportunity to expand its ecological niche breadth. Adaptive phenotypic plasticity can affect not only the ability to establish in a new environment, but also the ability to outperform the existing vegetation over time. Bromus inermis (smooth brome) and Poa pratensis (Kentucky bluegrass) are invasive species in tall- and mixed-grass prairie ecosystems. The objectives of this two-part study were to quantify the adaptive plasticity of biomass accumulation and tiller production in …

The Ecology And Evolution Of Rare, Soil Specialist Astragalus Plants In The Arid Western U.S., Joseph M. Statwick

Electronic Theses and Dissertations

Organisms that specialize in uncommon habitats are, by their very nature, inherently uncommon. Specialization has its advantages, namely reduced competition and predation, but it also incurs costs. Specialists often have small population sizes, narrow ranges, and fragmented habitat, all of which engender negative consequences on an evolutionary timescale. Herein, I examine benefits and costs of specialization in selenium-hyperaccumulating plants in the genus Astragalus (Fabaceae). These plants are disproportionately likely to be rare and of conservation concern. Thus, I optimized germination pretreatments for Astragalus species such that seed loss can be minimized during ex situ cultivation, and found that physical scarification …

Classifying And Mapping Native Grasslands Of South Dakota's Northern Prairie Coteau And Characterizing Habitat For Dakota Skipper Conservation, Diane M. Narem

Electronic Theses and Dissertations

Native tallgrass prairie is becoming increasingly rare due to conversion and degradation, putting pressure on endemic prairie species such as the federally threatened Dakota skipper butterfly (Hesperia dacotae). To develop a conservation plan for the butterfly in South Dakota, accurate vegetation classification, mapping, and characterization are critical. The objectives of this study were to 1) rank prairie condition, 2) classify and map upland prairie, 3) characterize and compare vegetation at Dakota skipper inhabited and formerly inhabited sites, and 4) identify potential Dakota skipper habitat within a 225 mi2 (58,275 hectares) study area of the SD Prairie Coteau. Condition metrics were …

Cause And Impacts Of The Early Season Collapse Of Lilium Grayi (Gray’S Lily), On Roan Mountain, Tn/Nc, Russell J. Ingram

Electronic Theses and Dissertations

A population of the rare Southern Appalachian endemic species Lilium grayi, (Gray’s lily) Roan Mountain, TN/NC was monitored for 2 years to determine the cause and impact of an early season collapse. High concentrations of the Lilium spp. host-specific fungal phytopathogen, Pseudocercosporella inconspicua (G. Winter) U. Braun were associated with 19/20 symptomatic and 0/30 asymptomatic plants. Strength of the association between pathogen and disease and the replication of disease symptoms in 4/4 healthy hosts showed that P. inconspicua was the causal agent of the disease referred to as lily leaf spot. Disease had a severe impact on the population …

Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler

Electronic Theses and Dissertations

This study examined the long-term patterns in vascular plant composition on three islands in Lake Winnipesaukee, NH. It also tested the role of island biogeography in ecology as it analyzed the effectiveness of a land use plan implemented on the islands. Samplings were made on the islands in the summer of 2011 and were compared to earlier samplings in 1978, 1991, and 2001. The flora was observed and measured in 25 permanent plots that were established on the three islands in 1978. The understory flora was measured by presence and percent cover and the overstory was measured by frequency and …

Reestablishing The Juneberry On The Fort Berthold Indian Reservation: Cultural, Horticultural, And Educational Connections, Kerry E. Hartman

Electronic Theses and Dissertations

Tribal people of the Northern Great Plains have utilized plants for centuries. Amelanchier anifolia (Juneberries/Serviceberries) historically played an important part in the diet and culture of the Mandan, Hidatsa, and Arikara (MHA) Tribal Nations. Research conducted as part of this study into historical and contemporary uses of the Juneberry by MHA Tribal Members indicated extensive historical use and a high interest in Juneberry reestablishment for cultural, nutritional, and economic reasons. Previous research on Juneberries has investigated factors including state of dormancy, propagation method, transplant type, and mulch type. Another purpose of this study was to elucidate the impact of presence …

Evidence Of Ecological Speciation In Phacelia., Pamela Michele Glass

Electronic Theses and Dissertations

Phacelia purshii Buckley and P. fimbriata Micheaux are two species that are nearly morphologically indistinguishable. Seed germination experiments showed that the high elevation endemic, P. fimbriata requires lower temperatures to trigger germination. Following interspecific crosses, pollen tubes enter ovules and maternal tissue of the gynoecium matures but hybrid diploid and triploid organs fail to develop. DNA sequences from the ribosomal DNA internal transcribed region showed that P. fimbriata and P. purshii comprise a monophyletic clade but that P. fimbriata is more differentiated from related species. In contrast, P. purshii supported significantly higher levels of intraspecific polymorphism. Phacelia fimbriata and P. …

The Columnar Junipers Of Western North Dakota (An Investigation Into The Cause Of Their Columnarity), James M. Murphy

Electronic Theses and Dissertations

The objective of this report is to focus on the evaluation of the presence and amount of ethylene in the burning lignite fumes and to search for morphogenetic factors in the lignite at the Slope County site. The former was considered to be more important and was investigated more thoroughly.

The Development Of The Megagametophyte Of Ailanthus Altissima., Esther L. Bossung 1912-1994

Electronic Theses and Dissertations

No abstract provided.

A Study Of Mahogany., Roy A. Lawrence

Electronic Theses and Dissertations

No abstract provided.

The Abortion Of Essential Organs In The Imperfect Flowers Of Benzoin Aestivale, Norris M. Paulson

Electronic Theses and Dissertations

There have been a number of investigations dealing with the abortion of essential organs in the imperfect flowers. Ulvin submitted a paper on Abortive Stamens and Carpels in Lychnis alba, Simon described stamen and carpel abortion in Cucumis stativus, Schaffner was able to control sex expression in Arisamea triphyllum and secure sex reversal in Cannabis stiva, Bessey determined the relationship of sex to the age of pollen in Cannabis sativa.

A Comparison Of Certain Methods Of Assay Oil Of Chenopodium, Orville Peterson

Electronic Theses and Dissertations

As defined in the United States Pharmacoposis, tenth revision, oil of Chenopodiumis the volatile oil distilled with steam from the fresh, over-ground parts of the flowering and fruiting plant of Chenopodium embrosiesdes war antheimintieum. (Family Chenopodiasene) oil of chenopodium yields not less than 65 per cent of accaridel.

The Latex System In The Root Of Taraxacum Officinale, Eleanor Kelton Evenson

Electronic Theses and Dissertations

In 1930 Mr. Emil Madsen of this laboratory began some experimental work upon the roots of dandelions, for the purpose of determining the means by which a dandelion root, which has been cut off below the surface of the ground, regenerates new shoots. He found that such roots form adventitious buds in exposed pericycle and secondary phloem. Several such buds may be formed in a single root. They grow and appear above the ground as leafy shoot.

The Factors Affecting The Method Of Branching In Ailanthus Glandulosa., Emory W. Theiss

Electronic Theses and Dissertations

No abstract provided.

Certain Cultural Characteristics Of Digitalis Pupurea, (Linne) With A Proposed Chemical Assay, Clark W, Eidsmoe

Electronic Theses and Dissertations

Since its introduction into modern medicine digitalis has occupied a very important position in our material medica. Its widespread use as a remedy in conditions of failing heart, and its effectiveness as a diuretic in certain dropsical conditions have gained for it a reputation which is equaled by few other drugs. The opinion of pharmacologiate and physicians as to its mode of action and its field of clinical usefulness has been revised a number of times, and there is much diversity of teaching as to its use in special ailments. Among some workers there is a tendency to restrict its …

The Anatomy Of The Germinating Bulbil Of Lilium Tigrinum, Katherine Harris Tripp

Electronic Theses and Dissertations

Apparently very little, if any, anatomical investigation has been made of the bulbil of Lilium tigrinum, though it has often been used as a propagating organ and consequently, the problem suggested attractive possibilities in an almost virgin field of investigation. Collections were made from five different plants beginning Sept. 27, 1928 until July 22, 1929. The older bulbils were removed from the axils of the foliage leaves and fixed in formalin acetic alcohol. They were gradually dehydrated by treatment with alcohol increasing the percentage 10% from 50 up to 100%. Xylol treatment in increasing percentages was then resorted to, until …

The Effect Of Treatment With Ethylene Chlorhydrin Upon The Respiration Of Sweet Potatoes (Ipomea Batatas), Leon J. Tyler

Electronic Theses and Dissertations

1. Treatment with ethylene chlorhydrin produced marked results in the respiration of four of five varieties of sweet potatoes tried.
2. Not all varieties of sweet potatoes respond alike to the same treatment. Porto Rico variety of sweet potatoes did not respond to the treatment.
3. There was a considerable difference in the amount of CO₂ respired by different varieties.
4. The need for further research here with respect to the specific effect of chemicals upon the cell system becomes apparent and again emphasizes the importance of Biochemistry.
5. There was possibly an accelerative effect on sprouting due to increased respiratory processes brought about …