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Lifespan Of Prokaryote Model Organism Escherichia Coli K-12, Hyrum Gillespie

Undergraduate Honors Capstone Projects

Bacteria are amazingly resilient organisms, in that they have evolved and adapted to the many extreme environments of Earth (from salt, to pH, to temperature extremes etc.). The bacterial lifespan and death rates are as important as its growth rates in these extreme environments. Bacteria would be useful to determine the effects of age on single cells, but because bacteria reproduce asexually by binary cell fission (clonal replication), calculating the lifespan has proven elusive. Without the determination of a lifespan, age studies using bacteria have limited application. Further, it has been proposed that organisms whose somatic cell line is not …

Optimizing The Physical And Nutritional Environment Of Unleached Root-Zones, Curtis B. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unleached root-zones represent an environmental ideal by eliminating wasteful leaching of nutrients and water. NASA grows plants in space in unleached root-zones, incorporating polymer-coated fertilizer (PCF) into a ceramic media (Turface or Profile). However, lack of growth productivity in space has led to the need for research to improve the nutritional and physical environment of the root-zone, which is the objective of this research. PCF types are diverse in release characteristics and the effects of temperature and substrate water content have not been well characterized. In spite of widespread use, studies on chemical properties and applied studies to verify soil …

Evaluating Native Wheatgrasses For Restoration Of Sagebrush Steppes, Jayanti Ray Mukherjee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pseudoroegneria spicata and Elymus wawawaiensis are two native perennial bunchgrasses of North America's Intermountain West. Frequent drought, past overgrazing practices, subsequent weed invasions, and increased wildfire frequency have combined to severely degrade natural landscapes in the region, leading to a decline in the abundance of native vegetation. Being formerly widespread throughout the region, P. spicata is a favorite for restoration purposes in the Intermountain West. Elymus wawawaiensis, which occupies a more restricted distribution in the Intermountain West, is often used as a restoration surrogate for P. spicata. However, since most restoration sites are outside the native range of …

Ethnobotanical History And Seed Oil Chemistry Of The Physic Nut, Jatropha Curcas, Nathan M. Leclear

Theses and Dissertations - UTB/UTPA

Jatropha curcas L., Euphorbiaceae, is a small tree native to the neotropics. Despite renewed economic interests in Physic Nut, mainly for biodiesel production, a comprehensive analysis of the ethnobotanical history of J. curcas is lacking. An account of the pre-Columbian neotropical distribution of this species and its historical uses are presented. Using capillary gas chromatography, studies were conducted to quantify the natural variation in seed oil content and fatty acid composition of the seed oil from several species of Jatropha, including assessment of how these parameters change during seed maturation. Natural variation in seed oil content was detected (F7,93 = …

Refinement Of Innovative Watermelon Grafting Methods With Appropriate Choice Of Developmental Stage, Rootstock Type, And Root Treatment To Increase Grafting Success, Frederic Memmott

All Theses

ABSTRACT
Watermelon grafting methods used in Europe and Asia vary, but are based on efficiency, skill and needs. China mainly practices the whole insertion grafting method, whereas, Europe and Japan employ the one cotyledon (splice/slant–cut) grafting method. These methods are not suitable for grafting production in the U.S. due to the labor intensive and high labor cost necessary to successfully produce grafted transplants. This thesis introduced a modified grafting technique called the “Cotyledon Devoid Method” and in three experiments determined; 1) the rootstock leaf number stage (RLNS) at which the greatest grafting success is achieved; 2) the relationship between total …

Classification And Fertility Of Soils In The Big South Fork National River And Recreation Area Based On Landscape Position And Geology, Ryan H. Blair

Masters Theses

The Big South Fork National River and Recreation Area encompasses more than 50,585 hectares (125,000 acres) of the Cumberland Plateau along the border of Tennessee and Kentucky. Highly dissected and steep terrain have made accessibility to much of the park limited, thus little work has been done to investigate the formation of these soils. Seven native soil profiles were selected for chemical and physical analysis representing Pennsylvanian-aged acidic sandstone and shale geology and landforms. The objectives of this study included the characterization of selected native profiles by physical and chemical analysis, as well as classification using US Soil Taxonomy, to …

Establishing Buffalograss In Fine Fescue Turfgrass On The Central Coast Of California, Brittani Jean Axtell

Master's Theses

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] is a warm season, perennial grass native to the Great Plains from southern Canada to Mexico (Beetle, 1950). This newly developed, low input, turf-type grass is recommended for use on low maintenance sites (Falkenberg-Borland and Butler, 1982; Pozarnsky, 1983; Wu and Harivandi, 1989; Shearman et al., 2005). Recently, the use of buffalograss as a turfgrass has increased due to its drought tolerance, low nutrient requirements, and low growing height (Harivandi and Wu, 1995; Frank et al., 2004). It is an excellent choice in California where water use is limited. Unsightly winter dormancy of buffalograss …

Biomechanical And Morphological Changes In Leaf Abscission Zones During The Ontogeny Of Kalanchoe Pinnatum, Jillian Hodge

Undergraduate Honors Thesis Collection

Kalanchoe pinnatum is able to asexually reproduce with the help of its leaves. In K. pinnatum, embryos are embedded in the notches of a leafs margin. Through the process of abscission, when the plant is disturbed a leaf with embryos falls to the ground and the embryos grow into new plants. Thus, as leaves mature, they face conflicting functional demands to stay on the plant and continue their role in photosynthesis or fall off the plant and asexually reproduce. To examine if there is a point in the leafs development where abscission occurs more readily, I examined breaking strength in …

Interisland Variability Of Dune Plant Community Structure On Virginia's Barrier Islands, Justin K. Shafer

Biological Sciences Theses & Dissertations

The barrier islands of the Virginia Coast Reserve LTER site provide an opportunity to study interisland variability of dune plant communities. My research focused on the variation in biomass and diversity of communities among islands and dune positions. Grassy dunes of young, intermediate and old age were sampled on Smith, Hog, and Parramore Islands. Aboveground biomass was obtained from harvest plots, and roots were extracted from cores. Data were collected on depth to groundwater and total soil nitrogen. Variation in mean aboveground biomass was evident among the islands with the highest values on Hog Island, followed by Smith, then Parramore …

Ecological And Genetic Status Of The Purple Pitcher Plant, Sarracenia Purpurea L., In Maryland And Virginia, Philip M. Sheridan

Biological Sciences Theses & Dissertations

Sarracenia purpurea is a rare wetland plant in Virginia and a threatened species in Maryland, with two potential subspecies in the region. I utilized restriction fragments from the intron of the chalcone synthase gene to compare S. purpurea populations and determine whether the subspecies concept was supported. I performed a census of existing populations, compiled all known historical data on the species, and investigated the reasons for the species demise and predicted dates of extinction. Bloom phenology was examined to see if climate change may have influenced bloom period. Soil, vegetation, and climatic information was obtained to determine if taxonomic …

Analyses Of Arabidopsis Yellow Stripe-Like (Ysl) Family Of Metal Transporters, Heng-Hsuan Chu

Open Access Dissertations

Iron is one of the most important micronutrients used by living organisms. Iron is frequently a limiting nutrient for plant growth, and plants are a major source of iron for human nutrition. The most prominent symptom of iron deficiency in plants is interveinal chlorosis, or yellowing between the veins, which appears first in the youngest leaves. Iron deficiency anemia (IDA) is the number one human nutritional deficiency worldwide. In order to solve the problem of iron deficiency, it is desirable to breed plants that have increased iron in those parts that are consumed by humans. To do this, we must …

Evolutionary Perspective Of Nicotine To Nornicotine Conversion, Its Regulation And Characterization Of Ein2 Mediated Ethylene Signaling In Tobacco, Manohar Chakrabarti

University of Kentucky Doctoral Dissertations

Nicotine, nornicotine, anabasine and anatabine are four major alkaloids in tobacco, of which nicotine is predominant. In many tobacco cultivars and also in other Nicotiana species, nicotine is converted to nornicotine, which in turn gives rise to potent carcinogen NNN. Nicotine to nornicotine conversion via nicotine-N-demethylation is mediated by the CYP82E family of P450 enzymes. Tobacco (Nicotiana tabacum) converts in senescing leaves, while its diploid progenitors N.tomentosiformis and N.sylvestris convert in both green and senescing and only in senescing leaves, respectively. Previously it has been shown that N.tomentosiformis has different active conversion loci in green and senescing leaves. …

Cover Crops And Tillage Systems For Organic Corn Production In Kentucky, Alfonso Suarez

University of Kentucky Master's Theses

Organic corn (Zea mays L.) producers generally use intensive tillage for weed control. No-till methods reduce soil erosion, conserve water, maintain soil structure and reduce CO₂ emissions. The objective of this study was test different cover crops, tillage systems, N sources and N rates for organic corn production. Two tillage systems (no-till and moldboard plow), two cover crops [hairy vetch (Vicia villosa) and rye (Secale cereale)] and two organic N sources [Louisville Green (LG) and Nature Safe (NF)] at four N rates (45, 90, 135, 180 kg N ha^-1) were evaluated …

Chromium, Copper, And Arsenic Concentration And Speciation In Soil Adjacent To Chromated Copper Arsenate (Cca) Treated Lumber Along A Topohydrosequence, Donald Roy Schwer Iii

University of Kentucky Master's Theses

Arsenic (As), Chromium (Cr), and Copper (Cu) are ubiquitous in soils as a result of anthropogenic and geogenic processes. The fate of As, Cr, and Cu in the environment is largely governed by their speciation, which is influenced by soil physiochemical properties. This study investigated the influence of soil physiochemical properties and landscape position on As, Cr, and Cu concentration and speciation in soils adjacent to Chromated Copper Arsenate (CCA) treated lumber fence posts. Concentration gradients showed elevated total As and Cu adjacent to the three fence posts, which decreased with increasing distance from the posts. In addition, As and …

Improvement Of New Oil Crops For Kentucky, Watchareewan Jamboonsri

University of Kentucky Doctoral Dissertations

Three oil crops, chia (Salvia hispanica L.), flax (Linum usitatissimum L.), and castor (Ricinus communis L.), were studied because of their nutritional and industrial values. Chia and flax are rich in an ω3 fatty acid, α-linolenic acid, and castor is a very high oil producer and high in a hydroxy fatty acid. Ethyl methanesulfonate (EMS) and gamma rays were employed to mutagenize chia seeds to produce early flowering mutants. The M₁ population was grown and induced to flower by short-day photoperiods. The M₂ population was planted in the field in Lexington, KY in 2008. Early …

Modeling Water Use In Nursery Crops, Amy Fulcher

University of Kentucky Doctoral Dissertations

Water use is an important topic in the global agriculture community and is a critical input in nursery crop production. Several plants in the genus Cornus are important nursery crops. Not only are they economically relevant, they are found in grafted and seedling forms and parents and their hybrid are readily available in the trade, facilitating an assessment of water requirements. Anecdotal information suggests that Cornus taxa have differing stress tolerance and water use requirements. Research was conducted to characterize and model water use among Cornus taxa. Scanning electron microscopy and anatomy‐based micromorphological studies as well as transpiration chamber‐based studies …

Phylloplanins: Novel Antifungal Proteins On Plant Leaf Surfaces, Ryan William Shepherd

University of Kentucky Doctoral Dissertations

Secreted surface proteins are an innate immune defense component employed by animals to inhibit invading microbes. Surface proteins have not been documented in plants, even though the aerial leaf surface, or phylloplane, is a major site of pathogen ingress. We have discovered novel proteins, termed phylloplanins, which accumulate on leaf surfaces of Nicotiana tabacum, and we have isolated the gene Phylloplanin that is unique in gene databases. Natural and E. coli-expressed phylloplanins inhibit spore germination and limit leaf infection by the oomycete pathogen Peronospora tabacina.

We investigated the site of phylloplanin biosynthesis using biochemical techniques. These techniques …

Soil Water And Crop Growth Processes In A Farmer's Field, Susmitha Surendran Nambuthiri

University of Kentucky Doctoral Dissertations

The study was aimed to provide information on local biomass development during crop growth using ground based optical sensors and to incorporate the local crop status to a crop growth simulation model to improve understanding on inherent variability of crop field. The experiment was conducted in a farmer’s field located near Princeton in Caldwell County, Western Kentucky. Data collection on soil, crop and weather variables was carried out in the farm from 2006 December to 2008 October. During this period corn (Zea mays L.) and winter wheat (Triticum sp) were grown in the field. A 450 m …

Science Based Authentication Of Dietary Supplements: Studies On The Chemical Constituents, Analytical Method And Biological Activities Of Scutellaria Spp And Pfaffia Paniculata, Jing Li

Electronic Theses and Dissertations

During the last decade, the use of herbal medicine has expanded globally and gained popularity. With the tremendous expansion in the use of herbal medicine worldwide, safety and efficacy as well as quality control of herbal medicines have become more and more issues of concern for both health authorities and the public. Although herbal medicine has been in use for hundreds to thousands years, very limited science-based data exist to explicit its chemical constituents, pharmacological activities and toxicity. Therefore, lack of scientific evidence for herbal medicine usage elicits the need for systematic studies of herbal medicine, including phytochemical, analytical, and …

Field Scale Bromide Tranport As A Function Of Precipitation Amount, Intensity And Application Time Delay, Vicente Vasquez

University of Kentucky Master's Theses

Rapid and deep transport of solutes in soils can potentially pollute groundwater resources. Field estimates of solute leaching depth based on randomized sampling provide extremely variable field average estimates that confound the treatment effects of the leaching study with the high spatial variation of soil hydraulic properties. The purpose of this study was to investigate the spatial scale of variation of solute (Bromide) leaching depth, and apply this scale of variation to study the leaching depth of Bromide as a function of a sinusoidal application of transport causing factors, i.e., rainfall amount, intensity and application time delay. Solute leaching depth …

Efecto Del Biofertilizante Agroplux® Sobre La Producción De Biomasa Y La Calidad De Un Cultivo De Pasto De Corte Maralfalfa Pennisetum Sp. En El Municipio De Montenegro Quindío, Maria Fernanda Escudero Sierra, Juan Manuel Hernandez Patiño

Zootecnia

El estudio se realizó en la finca el Mirador ubicada en el municipio de Montenegro, Quindío, con el fin de analizar el efecto que tiene el Agroplux® asociado con bovinaza sobre el pasto Maralfalfa (Pennisetum sp.), utilizando tres tratamientos denominados: Testigo (TO), Agroplux® (AP) y Agroplux® + Bovinaza (APB). Cada uno de los tratamientos tuvo cuatro parcelas, divididas a su vez en cuatro subparcelas para los cuatro cortes realizados a los días 40, 60, 80 y 100. Para esto diariamente se realizó el conteo de hojas, macollos, medición de altura de las plantas y se tomó la temperatura máxima y …

Grazing Evaluation Of A Novel Endophyte Tall Fescue Developed For The Upper Transition Zone, Jennifer Michelle Johnson

University of Kentucky Doctoral Dissertations

A wild-type endophyte (Neotyphodium coenophialum [(Morgan-Jones & Gams) Glen Bacon & Hanlin]) that infects tall fescue [Lolium arundinaceum (Schreb.) Darbysh. = Schedonorous arundinaceum (Schreb.) Dumort.] imparts tolerances to moisture, heat, and grazing stresses, but also produces ergot alkaloids that adversely affect performance and physiology of cattle. Novel endophytes, developed by AgResearch Ltd. NZ, can sustain fescue persistence and productivity, but do not produce toxic ergot alkaloids. University of Kentucky Plant Breeder, T. D. Phillips Ph.D, developed a tall fescue experimental population (KYFA9301) for the upper transition zone. A 2-yr grazing experiment was conducted with steers to evaluate steer …

The Vascular Flora Of Greater San Quintín, Baja California, Mexico, Sula E. Vanderplank

CGU Theses & Dissertations

The plants of San Quintín (Baja California, Mexico) were documented through intensive fieldwork and the collection of herbarium specimens to create a checklist of species. This region is home to a diverse flora with high levels of local endemism and many rare plants. The flora documented in this study was compared to historical records from the region and shows the impact of agriculture and urbanization on the plants, including several extirpated species. A study of the perennial vegetation using a 1 km grid provides species distribution data for 140 native species, which were assessed to highlight areas of significant species …

Genetic Diversity, Micro Propagation, And Cold Hardiness Of Ilex Glabra (L.) A. Gray, Youping Sun

Electronic Theses and Dissertations

Ilex glabra (L.) A.Gray (inkberry) is a native evergreen shrub with dark green foliage and compact habit. This shrub has gained popularity in the northern landscapes of the United States and more nursery growers would like to produce it. To better understand genetic relationships among inkberry cultivars and breed cold-hardy cultivars for northern nursery growers and landscape specialists, the following projects were conducted. A group of 48 inkberry accessions and two other Ilex species (Ilex crenata Thunb. and I. mutchagara Makino) were studied using amplified fragment length polymorphism (AFLP) markers. A total of 229 markers between 50 and 500 base …

The Role Of Cuticle, Fatty Acids, And Lipid Signaling In Plant Defense, Ye Xia

Theses and Dissertations--Plant Pathology

Systemic acquired resistance (SAR) is initiated upon recognition of specific microbial effectors by cognate plant resistance proteins and immunizes distal tissues of plants against secondary infections. SAR involves the generation of a mobile signal at the site of primary infection, which then translocates to and activates defense responses in the distal tissues via some unknown mechanism(s). This study shows that an ACYL CARRIER PROTEIN 4 (ACP4), GLABRA1 (GL1) and ACYL CARRIER BINDING PROTEINS (ACBP) are required for the processing of the mobile SAR signal in distal tissues of Arabidopsis. Although acp4, gl1 and acbp plants generate the mobile signal, …

Assessing Genetic Differentiation Among Populations Of The Invasive Plant Impatiens Glandulifera In Maine, Jordan R. Schoonover

Honors Theses

The annual herbaceous plant Impatiens glandulifera Royle is native to the Himalayas and is a significant invasive species in Europe. In the past century, it was introduced to the United States, where it has become established in 12 states. This study evaluated genetic differentiation among four Maine populations, to address a theory that posits hybridization of distinct lineages as a trigger for invasiveness. Regions of microsatellite repeats were evaluated at two polymorphic loci for 41 plants sampled from the four populations. A striking finding was that the observed heterozygosity was substantially higher than the heterozygosity expected from random combination of …

The Wheat Bzip Factor, Taabf1, Mediates Aba-Induced Gene Expression In Bombarded Barley Aleurone Layers, Benjamin R. Keyser

Honors Theses

The plant hormone Abscisic acid (ABA) plays a central role in maturation and germination in seeds, as well as mediating adaptive responses to abiotic environmental stresses. ABA induces the expression of many genes, including late-embryogenesis-abundant genes such as HVA1. To elucidate the ABA signaling pathway leading to HVA1 expression, we focus on the bZIP factor TaABF1. Analysis of the interplay between ABA and TaABF1 in the aleurone cells of imbibing cereal grains indicated that the two are not additive in their induction of the HVA1 promoter. A synthetic ABA analog, PBI-51, did not specifically inhibit the effect of exogenous ABA …

Insights Into The World Of Pea Nodulation Using The Low Nodulator R50, Scott Clemow

Theses and Dissertations (Comprehensive)

Cytokinin oxidase (CKX) is the enzyme responsible for the degradation of cytokinin, a class of adenine-based plant hormones that stimulate cell division, among other physiological processes. The pea mutant R50 is characterized by having a pale leaf phenotype, dwarf stature, few lateral roots, low nodule formation, and elevated levels of endogenous cytokinins in its shoots, roots and nodules. When compared to that of the wild-type Sparkle, total CKX activity is low but the transcript levels of PsCKX1 are significantly higher. In this study, I investigated the expression of PsCKX1 throughout the development of a nodule and the localization of PsCKX1 …

The Pleiotropic Mutant R50 (Sym16): A Link Between Cytokinin And Starch Metabolism May Explain Its Seed Phenotype, Chengli Long

Theses and Dissertations (Comprehensive)

Cytokinins are a class of adenine-based plant hormones that stimulate cell divisions and are therefore essential for organ growth and development. The role that cytokinin plays in nodulation and that of R50 (syml6) in particular is very complex. In this study, a cytokinin antagonist and a cytokinin oxidase (CKX) inhibitor were used as tools to study the effects of cytokinin perception or cytokinin degradation on nodulation in pea, the cytokinin transduction pathway, especially that induced by CRE1/AHK4, and CKX play a significant role in pea nodulation. Comparison of the full length sequences PsCKX2 cDNAs from Sparkle and R50 …

Unrooted Stem Cutting Physiology; Water Use And Leaf Gas Exchange Of Severed Stem Cuttings, Peter Alem

All Theses

Stem cuttings are one of the most frequently used and successful methods of vegetative plant propagation. The understanding of unrooted cutting physiology, especially gas exchange and water flux, is crucial for successful propagation of healthy plants. Prior to root initiation, water uptake is limited and leafy stem cuttings are most vulnerable to wilting.
Experiments were carried out in the greenhouse with poinsettia cuttings to determine water uptake, photosynthesis, transpiration and stomatal conductance from the time of severing to rooting, including time spent in storage. Water uptake through the severed stem was investigated in the laboratory and growth chamber. Cutting gas …