Plant Biology Commons^™

Role Of The Sexual Cycle In Development Of Genotypic And Phenotypic Diversity In Gibberella Zeae, Sladana Bec

Theses and Dissertations--Plant Pathology

Gibberella zeae (anamorph Fusarium graminearum) is a homothallic ascomycete pathogen that is responsible for causing Fusarium head blight (FHB) of wheat and small grains. In addition to causing a reduction in yield, harvested grain is frequently contaminated with trichothecene mycotoxins that are harmful for human and animal health. Use of wheat varieties with resistance to FHB is an important strategy to lower its impact. In order to produce varieties with durable resistance, we must understand the origin and degree of genetic diversity present in the pathogen population. In my research, I focused my efforts on an investigation of the …

Saplings 2011, Sean M. Goins, Joseph Braner, Amy L. Myers, Charlie Jackson, Julia I. Chapman, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Sapling data (woody species >50 centimeters in height and <2.5 cm diameter at breast height) collected in 2011 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Overstory 2011, Sean M. Goins, Joseph Braner, Amy L. Myers, Charlie Jackson, Albert J. Burky, Julia I. Chapman, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Overstory data (woody species ≥2.5 centimeters in diameter at breast height) collected in 2011 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Elucidating The Biochemical Wizardry Of Triterpene Metabolism In Botroycoccus Braunii, Thomas Daniel Niehaus

Theses and Dissertations--Plant and Soil Sciences

B. braunii is a green alga that has attracted attention as a potential renewable fuel source due to its high oil content and the archeological record of its unique contribution to oil and coal shales. Three extant chemotypes of B. braunii have been described, namely race A, race B, and race L, which accumulate alkadienes and alkatrienes, botryococcene and squalene and their methylated derivatives, and lycopadiene, respectively. The methylated triterpenes, particularly botryococcenes, produced by race B can be efficiently converted to high quality combustible fuels and other petrochemicals; however, botryococcene biosynthesis has remained enigmatic.

It has been suggested that botryococcene …

Molecular And Chemical Dissection Of Cellulose Biosynthesis In Plants, Darby M. Harris

Theses and Dissertations--Plant and Soil Sciences

Plant cell walls are complex structures that must not only constrain cellular turgor pressure but also allow for structural modification during the dynamic processes of cell division and anisotropic expansion. Cell walls are composed of highly glycosylated proteins and polysaccharides, including pectin, hemicellulose and cellulose. The primary cell wall polysaccharide is cellulose, a polymer composed of high molecular weight !- 1,4-glucan chains. Although cellulose is the most abundant biopolymer on Earth, there is still a lot to learn about its biosynthesis and regulation. This research began by applying a variety of analytical techniques in an attempt to understand differences in …

2011 Wildflower Of The Year: White Oak, Quercus Alba, W. John Hayden

Biology Faculty Publications

Emblematic of strength and longevity, white oaks grace the deciduous forests of eastern North America.

Establishment Of Endomycorrhizal Fungi On Micropropagated Teak (Tectona Grandis L.F.), Maria I. Ramirez Caro, Ian Bennett, Nick Malajczuk

Research outputs 2011

No abstract available.

Plants As Objects: Challenges For An Aesthetics Of Flora, John Charles Ryan

Research outputs 2011

This paper presents the conceptual challenges to an aesthetic model of living plants based in embodied interaction with flora through smell, taste, touch, sound and sight. I argue that the science of aesthetics is deterministically visual. Drawing from theories of landscape aesthetics put forth by Carlson and Berleant, I outline four primary obstacles to an embodied aesthetics: plants as objects of sight, plants as objects of art, plants as objects of disinterestedness and plants as objects of scientific discourse. A multi-sensorial aesthetics of flora requires auto-centric proximity and degrees of intersubjectivity between the appreciator and the appreciated plant that raise …

Anthoethnography: Emerging Research Into The Culture Of Flora, Aesthetic Experience Of Plants, And The Wildflower Tourism Of The Future, John C. Ryan

Research outputs 2011

How does anthoethnography contribute to the development of understandings of aesthetic experiences of wild plants and wildflower tourism? As exemplified by the quintessentially aesthetic industry of wildflower tourism, the culture of flora represents diverse engagements between people and plants. Such complex engagements offer further avenues for research. The critical methodology of anthoethnography has been one such approach to circumscribing the values, practices and rhetoric of wildflower tourism. Interviews have revealed perceptual phenomena such as the orchid and everlasting effects as two counterpoised examples of the differences between visual aesthetic values occurring in the region. For appreciators such as Tinker, botanical …

Plants, Processes, Places: Sensory Intimacy And Poetic Enquiry, John Ryan

Research outputs 2011

As an arts-based research approach, poetic enquiry has been theorised and applied recently in the social sciences and in education. In this article, I extend its usage to eco-critical studies of Australian flora and fauna. The Southwest corner of Western Australia affords opportunities to deploy arts-based methodologies, including field poetry, for celebrating the natural heritage of a region of distinguished biodiversity. I suggest that lyric practices in places such as Lesueur National Park and Anstey-Keane Damplands in southern Perth can catalyse embodied engagements with flora. The outcome of these practices is the invocation of the multiple senses— including the proximities …

Heterogeneous Stress Response In A Clonal Invader (Imperata Cylindrica): Implications For Management, Sarah Grace Sanford

USF Tampa Graduate Theses and Dissertations

Life history traits such as growth, survival, and clonality can vary within a population. When such variation exists in a population of an invasive species, it can affect population dynamics, and if any part of the variation has a genetic basis the population can evolve in response to control regimes. Evolutionary responses to control efforts may shift the population towards a few more resilient genotypes, or towards different types in different microenvironments, depending on the scale of gene flow with respect to the patchiness of the environment. The purpose of this study is to examine whether the application of stress …

Edaphic, Microtopographic, And Light Characteristics Associated With The Endangered Running Buffalo Clover (Trifolium Stoloniferm) At The Blue Grass Army Depot, Madison County, Kentucky, Lance Austin Watt

Online Theses and Dissertations

Soil, microtopographic, and light parameters associated with federally endangered running buffalo clover (Trifolium stoloniferum) plants on the Blue Grass Army Depot, Richmond, KY, were examined during the 2004 and 2005 growing season. Study samples or measurements were determined at 27 "long-term" sites (plots which have had clover present since 1992-1994), 23 "disappeared" sites (plots which had clover in 1992-1994, but did not have plants present at the time of this study) and 25 random/control sites (randomly selected 1 m2 plots in areas in which running buffalo clover has never been reported).

Average precipitation on the Blue Grass Army Depot was …

Control Of Glucosylceramide Production And Morphogenesis By The Bar1 Ceramide Synthase In Fusarium Graminearum, William B. Rittenour, Ming Chen, Edgar B. Cahoon, Steven D. Harris

Department of Plant Pathology: Faculty Publications

The contribution of plasma membrane proteins to the virulence of plant pathogenic fungi is poorly understood. Accordingly, the objective of this study was to characterize the acyl-CoA dependent ceramide synthase Bar1 (previously implicated in plasma membrane organization) in the wheat pathogen Fusarium graminearum. The role of Bar1 in mediating cell membrane organization was confirmed as DBAR1 mutants failed to display a distinct sterol-rich domain at the hyphal tip. The DBAR1 mutants were non-pathogenic when inoculated onto wheat heads, and their in vitro growth also was severely perturbed. DBAR1 mutants were incapable of producing perithecia (sexual fruiting structures) and only produced …

The Sugar Sensor, Trehalose-6-Phosphate Synthase (Tps1), Regulates Primary And Secondary Metabolism During Infection By The Rice Blast Fungus: Will Magnaporthe Oryzae’S “Sweet Tooth” Become Its “Achilles’ Heel”?, Jesse Fernandez, Richard Wilson

Department of Plant Pathology: Faculty Publications

Rice blast disease is considered one of the most serious diseases of cultivated rice and is mediated by the causal agent, Magnaporthe oryzae. During infection, dome-shaped fungal cells, called appressoria, form on the surface of the leaf and generate turgor through the accumulation of glycerol. This enormous pressure is directed down onto a thin penetration hypha emerging from the base of the cell, forcing it through the surface of the rice leaf and allowing fungal colonization of the plant interior. The non-reducing disaccharide, trehalose, is present in conidia of M. oryzae and is mobilized during appressorium formation. The first …

Mechanisms Of Contact-Mediated Killing Of Yeast Cells On Dry Metallic Copper Surfaces, Davide Quaranta, Travis Krans, Christophe Espirito Santo, Christian Elowsky, Dylan W. Domaille, Christopher J. Chang, Gregor Grass

Department of Plant Pathology: Faculty Publications

Surfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivate Candida albicans and Saccharomyces cerevisiae within minutes in a process called contact-mediated killing. Cellular copper ion homeostasis systems influenced the kinetics of contact-mediated killing in both organisms. Deregulated copper ion uptake through a hyperactive S. cerevisiae Ctr1p (ScCtr1p) copper uptake transporter in Saccharomyces resulted in faster inactivation of mutant cells than of wild-type cells. Similarly, lack of the …

Synthesis, Linda H. Pardo, Linda H. Geiser, Mark E. Fenn, Charles T. Driscoll, Christine L. Goodale, Edith B. Allen, Jill S. Baron, Roland Bobbink, William D. Bowman, Christopher M. Clark, Bridget Emmett, Frank S. Gilliam, Tara Greaver, Sharon J. Hall, Erik A. Lilleskov, Lingli Liu, Jason A. Lynch, Knute Nadelhoffer, Steven S. Perakis, Molly J. Robin-Abbott, John L. Stoddard, Kathleen C. Weathers

Biological Sciences Faculty Research

Human activity in the last century has led to a substantial increase in nitrogen (N) emissions and deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the level of pollution that would be harmful to ecosystems is the critical loads approach. The critical load is dei ned as the level of a pollutant below which no detrimental ecological effect occurs over the long term according to present knowledge.

The objective of this project was to synthesize …

Intermediate Steps Of Loline Alkaloid Biosynthesis, Jerome Ralph Faulkner

University of Kentucky Doctoral Dissertations

Epichloë species and their anamorphs, Neotyphodium species, are fungal endophytes that inhabit cool-season grasses and often produce bioprotective alkaloids. These alkaloids include lolines, which are insecticidal and insect feeding deterrents. Lolines are exo-1-aminopyrrolizidines with an oxygen bridge between carbons 2 and 7, and are usually methylated and formylated or acetylated on the 1-amine. In previously published studies lolines were shown to be derived from the amino acids L-proline and L-homoserine. In addition the gene cluster involved in loline-alkaloid biosynthesis has also been characterized. In this dissertation a survey of plant-endophyte symbioses revealed a phenotype with only N-acetylnorloline. This …

Cloning, Expression Analysis, And Transformation Vector Construction Of Dam Homologs In Peach And Poplar, Yuhui Xie

All Theses

Genetic fine mapping and sequencing of the EVG locus in peach [Prunus persica (L.) Batsch] identified six tandem arrayed Dormancy-Associated MADS-box (DAM) genes as candidates for regulating growth cessation and terminal bud formation in the non-dormant evergrowing (evg) mutant. Since the mutant is lacking expression of six genes in the mapped locus, further functional analysis is needed to narrow the list of gene candidates for the non-dormant evg phenotype. Here I report three sets of experiments designed to functionally test DAM genes in peach and their homologs in a model tree, hybrid poplar.
First I constructed overexpression and knockdown vectors …

Registration Of Seven Winter Wheat Germplasm Lines Carrying The Wsm1 Gene For Wheat Streak Mosaic Virus Resistance, Jasdeep S. Mutti, P. Stephen Baenziger, Robert A. Graybosch, Roy French, Kulvinder S. Gill

Department of Agronomy and Horticulture: Faculty Publications

Seven winter wheat (Triticum aestivum L.) germplasm lines carrying the Wsm1 gene conferring resistance to Wheat streak mosaic virus (WSMV)—Alliance-Wsm1 (Reg. No. GP-858, PI 653710), Arrowsmith-Wsm1 (Reg. No. GP-859, PI 653711), Goodstreak-Wsm1 (Reg. No. GP-860, PI 653712), Harry-Wsm1 (Reg. No. GP-861, PI 653713), Millennium-Wsm1 (Reg. No. GP-862, PI 653714), Wahoo-Wsm1 (Reg. No. GP-863, PI 653715), and Wesley-Wsm1 (Reg. No. GP-864, PI 653716)—were codeveloped by Washington State University, Pullman, WA; the University of Nebraska, Lincoln, NE; and the USDA-ARS. These seven different winter wheat cultivars were selected to provide more sources of effective …

Can Resource-Use Traits Predict Native Vs. Exotic Plant Success In Carbon Amended Soils?, Robert J. Steers, Jennifer L. Funk, Edith B. Allen

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Productivity in desert ecosystems is primarily limited by water followed by nitrogen availability. In the deserts of southern California, nitrogen additions have increased invasive annual plant abundance. Similar findings from other ecosystems have led to a general acceptance that invasive plants, especially annual grasses, are nitrophilous. Consequently, reductions of soil nitrogen via carbon amendments have been conducted by many researchers in a variety of ecosystems in order to disproportionately lower invasive species abundance, but with mixed success. Recent studies suggest that resource-use traits may predict the efficacy of such resource manipulations; however, this theory remains largely untested. We report findings …