Life Sciences Commons^™

In Vitro Propagation, Regeneration, Attempted Tetraploid Induction, And Agrobacterium-Mediated Transformation Of Euphorbia Pulchurrima ‘Winter Rose’™, Kimberly Ann Pickens

Doctoral Dissertations

Poinsettia, Euphorbia pulchurrima, is the number one potted flowering plant in the United States. ‘Winter Rose’™ is a very popular cultivar with more than one million plants sold each year. To further improve this cultivar, particularly for larger flower heads and free branching, this research aimed at establishing some in vitro systems for application of biotechnology to poinsettia genetic improvement.

A protocol was established for in vitro axillary bud proliferation using greenhouse grown terminal buds. Buds were placed on Murashige-Skoog (MS) basal medium supplemented with benzlyaminopurine (BA). Explants produced the greatest number of axillary buds on medium containing between 2.2-8.8 …

Levels And Patterns Of Genetic Diversity In The Rare And Endangered Cumberland Stitchwort, Minuartia Cumberlandensis (Caryophyllaceae), Charles Thomas Winder

Masters Theses

Sequences of a highly variable nuclear gene (G3pdh) were used to characterize genetic diversity within and among populations of the endangered rockhouse endemic, Minuartia cumberlandensis (Wofford and Kral) McNeill (Caryophyllaceae), and compared to a widespread and abundant related species, M. glabra (Michaux) McNeill. By reconstructing phylogenetic relationships among G3pdh variants (haplotypes) and observing the geographical distribution of those ordered variants, an attempt was made to gauge the effects of historical and contemporary population processes acting within the species, particularly those with potential implications for long-term conservation. Both M. cumberlandensis and M. glabra were found to have high overall …

Evaluation Of Botanical Oil Formulations For Management Of Powdery Mildew And Mites, Adriane Lorraine Cannon

Masters Theses

Experiments were conducted to evaluate the effects of newly created soybean oil formulations on powdery mildew (Erysiphe pulphra ), photosynthesis, phytotoxicity, and broad mites (Polyphagotarsonemus latus (Banks)) on dogwood ( Cornus florida (L.) 'Cloud Nine') trees, and to evaluate the amounts of formulations that are deposited and washed off of peach (Prunus persica, (L.)) leaves, dormant oak (Quercus phellos, (L.) ), and viburnum ( Viburnum x juddii) twigs after simulated rainfall. Oil treatments were applied using a back pack mist blower sprayed pre- and post- inoculation of powdery mildew to evaluate powdery mildew, …

Seasonal Abundance Of Mosquitoes (Diptera: Culicidae) At A High And Low Prevalence Site For La Crosse Encephalitis In Eastern Tennessee, Nathan David Caldwell

Masters Theses

La Crosse (LAC), a California (CAL) serogroup bunyavirus, is the most prevalent pediatric arboviral disease in the United States and accounts for virtually all encephalitis cases associated with CAL serogroup arboviruses. In Tennessee, USA, prior to the drastic increase of confirmed La Crosse (LAC) encephalitis cases in 1997, the sum of documented cases reported to the Tennessee Department of Health totaled 9. During subsequent years in Tennessee (1997 to 2003), an average of 12 cases has been reported annually. Approximately 62% of these reported cases have occurred in the months of July and August. The native, container-inhabiting mosquito Ochlerotatus triseriatus …

Systematics And Species Concepts In The Genera Lentinus Fr. And Panus Fr., With Emphasis On The Lentinus Tigrinus, L. Crinitus And Panus Lecomtei Complexes, Edward A. Grand

Doctoral Dissertations

The monographic work of Pegler (1983) on Lentinus has established the taxonomic guidelines for most recent studies involving members of the genus (Moncalvo et al. 2002, Rolen 2001, Krüger 2002). Pegler’s taxonomic hierarchy combined both Lentinus Fr. and Panus Fr. into one large genus, Lentinus Fr. The combination of these genera and its validity was one of the reasons for beginning this study. For generic level comparisons, ribosomal DNA sequence data can be helpful for determining relationships among taxa (Binder and Hibbett 2002, Hibbett and Vilgalys 1991, 1993, Hibbett and Donoghue 2001, Moncalvo et al. 2002, Thorn et al. 2000). …

Vegetation Characteristics Associated With Small Mammal Populations In The Las Vegas Wash, Christine Therese Herndon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Percent litter, average litter depth, percent bare ground, vegetation density, vegetation canopy, and distance to an ecotone boundary were measured and compared to small mammal capture locations in the Las Vegas Wash. Neotoma lepida appear to be greatly dependent upon the foliage litter of T. ramosissima. Alternatively, ecotone boundaries appear to be the most important factor affecting Dipodomys merriami distributions. Peromyscus eremicus distributions may be predicted based on vegetation density and increased canopy during shorter, winter torpor periods. Chaetodipus penicillatus were consistently associated with dense, seed-bearing vegetation, although C. penicillatus is extremely opportunistic and vegetation density should not limit their …

Examining Varroa-Resistant Honey Bee Queens From Commercial Breeders: Colony Productivity, Hygienic Behavior, Suppression Of Mite Reproduction, And The Relationship Of Juvenile Hormone Iii To Mite Abundance, Laura L. Bryant

Masters Theses

This research was conducted to assess the performance of commercially bred honey bee queens sold as resistant to the parasitic mite, Varroa destructor. The study’s objectives were to: 1) Compare honey and pollen stores and V. destructor infestation in colonies established with hybrid Russian, SMR, and control queens, 2) Determine levels of hygienic behavior and mite non-reproduction in the same colonies, and 3) Determine the relationship between juvenile hormone III in honey bee larvae and V. destructor reproduction.

In Part One, when honey, pollen, and V. destructor levels were measured, no significant differences were found among types of queens. …

The Effects Of Elevated Co2 And Environmental Variation On Plant Phenotype, Herbivore Performance, And Evolutionary Potential In A Brassicacae Model System, John Michael Landosky

Dissertations

No abstract provided.

Assessment Of Insects, Primarily Impacts Of Biological Control Organisms And Their Parasitoids, Associated With Spotted Knapweed (Centaurea Stoebe L. S. L.) In Eastern Tennessee, Amy Lynn Kovach

Masters Theses

Spotted knapweed [Centaurea stoebe L. ssp. micranthos (Gugler) Hayek] (formerly C. maculosa Lam. and C. biebersteinii DC.) (Asteracea) (referred to here as C. stoebe L. sensu lato) a non-indigenous, invasive weed, has been the focus of a biological control program using a complex of insects for more than 30 years in North America. Spotted knapweed is a prolific seed producer and produces two phytotoxic chemicals (catechin and cnicin), both enhancing the invasiveness of the weed. In Tennessee, information about this common weed of roadsides and its associated insects is not well known.

This research consists of five components: …

Mycorrhizal Symbiosis And The Response Of Sorghum Plants To Combined Drought And Saline Stresses, Keun Ho Cho

Masters Theses

Arbuscular mycorrhizal (AM) symbiosis has been reported often to improve the abilities of host plants to tolerate drought stress. The physiological mechanism is uncertain, but one idea is that the effect might be linked to resistance to salt stress. Several studies have shown more growth in crop plants colonized with AM fungi than nonAM control plants under salt stress. Drought and salt stresses frequently occur together in nature and their initial symptoms in plants are similar. It may be interesting to scrutinize their physiological interaction in host plant as a function of AM fungi. Therefore, the objectives of my studies …

Molecular Systematics Of North American Eupatorium, Kunsiri Chaw Siripun

Doctoral Dissertations

This study had two primary goals: first, to prepare a thorough taxonomic revision of North American Eupatorium, and second, to conduct initial evaluations using molecular techniques of how diploid and polyploid populations of Eupatorium rotundifolium and E. sessilifolium relate to one another. Nuclear ribosomal internal transcribed spacer (ITS) region and chloroplast DNA (trnC-psbM) sequences were used for molecular analysis, which allowed assessment of relationships of the polyploidy samples based on both a biparentally and a maternally inherited marker. The Inter Simple Sequence Repeat (ISSR) method was used for examining the relationships among diploid and polyploid populations …

An Evaluation Of Submersed Aquatic Vegetation Transplanting Methods For Lake Pontchartrain Restoration, Donald Anthony Rodrigue Jr.

University of New Orleans Theses and Dissertations

The general goals of this study were to evaluate transplant methods for Lake Pontchartrain submersed aquatic vegetation (SAV) restoration, and to compare survival and expansion of transplanted SAV among four sites. Two experiments were conducted from summer 2000 through spring 2001 at two north shore and two south shore sites in Lake Pontchartrain. Experiment 1 involved testing the effects of transplanting with matting, staples, exclosures, and interspecific interaction on survival and expansion of Ruppia maritima and Vallisneria americana transplants in Lake Pontchartrain. Experiment 2 involved testing the effects of transplanting with matting, staples, and plugs on Ruppia survival and expansion. …

Does Seed Size Affect The Rate Of Germination And Early Seedling Growth In Hairy Vetch?, Joy Ekpo

McCabe Thesis Collection

Size is an important characteristic of seed quality because larger seeds with larger volume contain more resources and are likely to exhibit greater vigor than smaller seeds (Ellis, 1992). In a range of plant species, seed size has been shown to affect germination rate, emergence rate, success of establishment, and growth (Black 1957; Bentley et al. 1980; Sanderson et al. 2002). Hairy vetch is an annual legume that is used for improvement of soil for pasture and to provide ground cover protecting against erosion (Duke 1981; Undersander 2002; Sattell et al 1988). Problems facing the establishment of hairy vetch are …

Moisture Potential Affects Rate Of Leaf Appearance In Cool Season Grasses, Nina Cherone Terrell

McCabe Thesis Collection

The rate of leaf appearance and onset of growth in cool season grasses may be influenced by soil moisture potential and exposure to below freezing temperatures. Levels of moisture potential and days exposed to freezing temperatures, which will restrict leaf appearance, are not well defined. The first part of this study was to determine the effects of different moisture potentials on the leaf appearance rates in two cool season grasses. Italian ryegrass (IRG) and tall wheat grass (TWG) were grown hydroponically at 4 moisture potentials in seed pouches in an incubator under a photoperiod of 13 hours light and 11 …

A Study Of Invasive Species Cover Near Roads In A Red Rock Canyon Blackbrush Community, Christopher Keough

UNLV Theses, Dissertations, Professional Papers, and Capstones

The monitoring of Mojave Desert plant communities during and following disturbance is an important process that could provide invaluable information about disturbance/recovery regimes in similar arid environments across the globe. Blackbrush communities are of particular interest because of their low replacement rate, which makes them highly susceptible to disturbance. Roads in the Mojave Desert have been associated with soil compaction resulting in a lack of vegetation as well as an increase in invasive species cover in the immediate proximity. To investigate these statements, eight fifty-foot line transects were established in each of three plot types (perpendicular to dirt roads, perpendicular …

Structural Changes In The Red Spruce-Fraser Fir Forest, Michael R. Mancusi

Masters Theses

Since the early 1900s the southern Appalachian red spruce (Picea rubens Sarg.)-Fraser fir (Abies piceae (Pursh) Poir.) forests have been subjected to numerous destructive influences. Historical logging practices, fire, exotic insect infestations, acidic deposition, and global climate change have demonstratively altered the structure and composition of this fragile ecosystem. Most profound was the discovery in 1957 of the balsam woolly adelgid (Adelges piceae Ratz. Homoptera: Adelgidae ), an exotic sap-sucking aphid. A study was initiated in the Great Smoky Mountains National Park, which contains 74% of the red spruce-Fraser ecosystem. Thirty-six 20x20 m permanent plots untouched by logging …

Insect Fauna Associated With Eastern Hemlock, Tsuga Canadensis (L.), In The Great Smoky Mountains National Park, Stanley Earl Buck Iii

Masters Theses

Eastern hemlock, Tsuga Canadensis (L.), is an integral part of the forest system in eastern North America. These trees contribute to the biological diversity, environmental health, and economic stability of the regions that they inhabit by producing unique microclimates, cool shady recreational areas, and unmatched beauty. Information regarding the insect fauna associated with eastern hemlock is sparse and scattered with in the literature. Because of this, the insect fauna associated with eastern hemlock was assessed at four sites, representing new and old growth, and nine alternate sites in the Great Smoky Mountains National Park (GSM). Sites were sampled using malaise …

Quantifying Losses Of Understory Forage In Aspen Stands On The Dixie And Fishlake National Forests, Barton R. Stam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The West has lost up to 60% of its historic aspen stands over the last century, probably as a result of the successional tendency of aspen to be replaced by coniferous species in the absence of periodic fires. One of several major impacts of this change is the loss of understory forage as conifer canopy cover increases. I measured understory biomass in aspen stands ranging from 0% to 81 % absolute conifer cover in the canopy and found that understory production declines exponentially as conifers replace aspen. I also did an economic analysis to determine the value of the forage …

Cattle As Grazing Management And Seed Dispersal Tools For Increasing Native Species Diversity On Great Basin Rangelands, Marina K. Whitacre

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments evaluated: 1) the influence of seed intake and gut retention time on seed passage, recovery, and germinability; 2) fecal seeding and broadcast /trampling as techniques to incorporate seeds into a well-established Agropyron desertorum (Fisch.) Schult. stand in Skull Valley , Utah; 3) intensive grazing as a means to reduce Agropyron biomass and increase establishment and survival of seeded species; and 4) the recovery and germinability of seed extracted from dung collected from the field. Two shrubs (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young and Atriplex confertifolia Torr. & Frem.), a grass (Elymus elymoides (Raf.) …

Defining Soil Type And Habitat Characteristics Of The Arctomecon Californica, Philip S. Childers

UNLV Theses, Dissertations, Professional Papers, and Capstones

A. californica can be considered a rare endemic species, which is believed to be restricted by unique soil relationships. These relationships make the species vulnerable to anthropogenic habitat disturbance. Although A. californica is listed as critically endangered by the state of Nevada, further research is needed before the species can be listed as federally endangered or threatened. This study used primary observational data and secondary GIS compatible data to characterize A. californica habitat. Representative sampling techniques were used to select observations from derived soil types. Although a majority of A. californica populations were found to occur in gypsic soil types, …

Seed Bank Response To Fire And Successional Trajectory Of A Virginia Small Depression Pocosin, Jay F. Bolin

Biological Sciences Theses & Dissertations

Pocosins are depressional wetlands maintained by fire. Plants in fire adapted systems can use a variety of mechanisms for survival and recruitment. I examined the seed bank response to fire (500 to 700 °C) and wet heat treatments (50 and 75 °C) in a Virginia small depression pocosin. I quantified seedling abundance, richness, and Sphagnum density. Extant vegetation was sampled with a nested plot design at each seed bank sampling area. The seed flora was compared with the extant vegetation at three size classes with Sorenson similarity values. Data from the fire treatment indicates that a simulated drought burn may …

Loline Alkaloid Biosynthesis In Neotyphodium Uncinatum, A Fungal Endophyte Of Lolium Pratense, Jimmy Douglas Blankenship

University of Kentucky Doctoral Dissertations

Some endophytes in mutualistic associations with Festuca, Lolium and other grass species produce insecticidal loline alkaloids (1-aminopyrrolizidines; LA). These loline alkaloids have a saturated pyrrolizidine ring system (two-rings sharing a carbon and nitrogen atom), a 1-amine substituted with methyl, acetyl, or formyl groups, and an oxygen bridge between C-2 and C-7. The development of a reliable system of production of LA in cultures of the Lolium pratense (meadow fescue) endophyte, Neotyphodium uncinatum, facilitated work on the LA biosynthetic pathway. N. uncinatum produced norloline, loline, methylloline, N-acetylnorloline (NANL), N-formylloline (NFL), and N-acetylloline as detected in culture filtrates. The total production …

An Analysis Of Vegetation And Environmental Parameters At Mitigated Wetland Sites Located In The Upper Scioto River Drainage Basin, Central Ohio, Desiree L. Lawson

Theses, Dissertations and Capstones

The construction of wetland mitigation sites to compensate for authorized losses is necessary under Section 404 of the Clean Water Act. Many mitigation sites have been determined to be unsuccessful. Monitoring of sites is necessary to determine if functions of natural wetlands have been replaced. Six mitigation sites in the Upper Scioto River watershed in central Ohio were chosen for study. Representative transects were established beginning in uplands adjacent to the wetlands (old field, OF), running through areas characterized by seasonal inundation (seasonally pooled, SP) and ending in permanent pools of inundation characterized by little or no vegetation (permanent pooled …

Effect Of Light Duration On Pulvinar Motor Organ Movements In Phaseolus Vulgaris, Thomas William Rinehart

Presidential Scholars Theses (1990 – 2006)

With a well established model in place, the main objective of this study will be to determine if the pulvinar motor organs have a threshold radiation level to elicit paraheliotropic movements. Plants will be illuminated with full spectrum light at varying intensities and periods. Observation will take place minute-by-minute in an effort to denote certain lighting conditions which might trigger paraheliotropism.

The Use Of Proline To Determine Salt Tolerance In Eucalyptus Species And Clones, Andrew J. Woodward

Theses: Doctorates and Masters

There have been a number of studies that have examined the Eucalyptus spp. for their salt and waterlogging tolerance: but they have done so using conventional methods. A wide range of plants are known to produce greater amounts of proline when stressed, be it salt, temperature, 'drought or several other types of stress. This study looked at production of proline in salt stressed eucalypts to determine whether it can be used to differentiate between individuals andspecies. A range of Eucalyptus species and salt tolerant clones of E. camaldulensis were grown to investigate their proline response to salt stress.

Development And Light Response Of Leaves Of Metasequoia And Close Relatives, Xiaochun Li

Electronic Theses and Dissertations

Metasequoia glyptostroboides is a useful nearest living relative (NLR) of the Eocene fossil Metasequoia. Research on modern Metasequoia might give us some clues about its fossil counterpart. During this study the leaf anatomy of Metasequoia, Glyptostrobus, Sequoia and Taxodium was investigated with light microscopy and transmission electron microscopy. Metasequoia exhibits several characteristics of typical sciaphilic plants, such as slightly arched outer cell walls in the adaxial epidermal cells, strongly arched outer cell walls in the abaxial epidermal cells, mesophyll composed of spongy cells, chloroplasts with well-developed grana not only in mesophyll cells but in both the adaxial and abaxial epidermis. …

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

Dissertations, Theses, and Masters Projects

No abstract provided.

Identification Of Bacterial Pathogens Causing Panicle Blight Of Rice In Louisiana, Xianglong Yuan

LSU Master's Theses

Four hundred and two bacterial isolates isolated on the semi-specific S-PG medium from diseased rice tissues showing symptoms of panicle blighting. These isolates were purified using serial dilution in sterile water and replating on S-PG medium. A total of 420 single isolates were obtained. These isolates were subjected to pathogenicity tests on rice (Oryza sative L. cv. Cypress). Based on these tests, 339 isolates were used in BiologTM tests and identified to the species level. Bacterial strains from 39 species in 16 genera were identified, including 52 isolates representing15 Pseudomonas species and 261 isolates representing six Burkholderia species. The remaining …

Cercospora Leaf Blight Of Soybean: Pathogen Vegetative Compatibility Groups, Population Structure, And Host Resistance, Guohong Cai

LSU Doctoral Dissertations

Nitrogen nonutilizing mutants were used to assess vegetative compatibility of 58 isolates of Cercospora kikuchii, 55 of which were isolated from soybean plants in Louisiana. Only 16 of 56 self-compatible isolates were assigned to six multi-member vegetative compatibility groups (VCGs), 01-06, with two or three isolates in each VCG. The other 40 isolates were not vegetatively compatible with any isolates other than themselves. All six multi-member VCGs contained isolates from different soybean cultivars, and three included isolates from different locations. Only one VCG included isolates both from soybean leaves and from seeds, while two and three multi-member VCGs included isolates …

Tissue Culture And Transformation Of Introducing Genes Useful For Pest Management In Rice, Shuli Zhang

LSU Doctoral Dissertations

Sheath blight (SB), caused by Rhizoctonia solani K¨¹hn, is a major rice disease internationally and in the southern rice area of the Unites States, including Louisiana. Breeders have incorporated partial resistance into commercial rice varieties to control the disease, but a higher level of resistance is needed. It has been demonstrated that the pathogenesis-related (PR) proteins ¦Â-1, 3-glucanase and chitinase are components of effective defense mechanisms for protecting plants against fungal pathogens. This research was conducted to co-transform the ¦Â-1, 3-glucanase, chitinase and bar genes into the rice variety Taipei 309 using the hpt gene for resistance to hygromycin B …