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Articles 121 - 150 of 767

Full-Text Articles in Animal Sciences

Habitat Selection And Response To Disturbance By Pygmy Rabbits In Utah, Robert John Edgel Mar 2013

Habitat Selection And Response To Disturbance By Pygmy Rabbits In Utah, Robert John Edgel

Theses and Dissertations

The pygmy rabbit (Brachylagus idahoensis) is a sagebrush (Artemisia sp.) obligate that depends on sagebrush habitats for food and cover throughout its life cycle. Invasive species, frequent fires, overgrazing, conversion of land to agriculture, energy development, and many other factors have contributed to recent declines in both quantity and quality of sagebrush-steppe habitats required by pygmy rabbits. Because of the many threats to these habitats and the believed decline of pygmy rabbit populations, there is a need to further understand habitat requirements for this species and how they respond to disturbance. This study evaluated habitat selection by pygmy rabbits in …

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Microbial Responses To Coarse Woody Debris In Juniperus And Pinus Woodlands, Deborah Monique Rigby Mar 2013

Microbial Responses To Coarse Woody Debris In Juniperus And Pinus Woodlands, Deborah Monique Rigby

Theses and Dissertations

The ecological significance of coarse woody debris (CWD) is usually highlighted in forests where CWD constitutes much of an ecosystem's carbon (C) source and stores. However, a unique addition of CWD is occurring in semi-deserts for which there is no ecological analog. To stem catastrophic wildfires and create firebreaks, whole Juniperus osteosperma (Torr.) and Pinus edulis (Engelm.) trees are being mechanically shredded into CWD fragments and deposited on soils previously exposed to decades of tree-induced changes that encourage "tree islands of fertility." To investigate consequences of CWD on C and nitrogen (N) cycling, we evaluated microbial metabolic activity and N …

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The Influence Of Anthropogenic Development Of Water On Coyotes And Kit Foxes In The Great Basin And Mojave Deserts, Lucas Keith Hall Mar 2013

The Influence Of Anthropogenic Development Of Water On Coyotes And Kit Foxes In The Great Basin And Mojave Deserts, Lucas Keith Hall

Theses and Dissertations

Anthropogenic provisioning of water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence distribution, competition dynamics, and behavior of native species. To elucidate the potential influences of water developments on native species, we tested hypotheses concerning the occurrence and behavior of native kit foxes (Vulpes macrotis). First, we tested the indirect effect of water hypothesis (IEWH) which proposes that water developments negatively affect the arid-adapted kit fox by enabling a …

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Application Of Genome Reduction, Next Generation Sequencing, And Kaspar Genotyping In Development, Characterization, And Linkage Mapping Of Single Nucleotide Polymorphisms In The Grain Amaranths And Quinoa, Scott Matthew Smith Mar 2013

Application Of Genome Reduction, Next Generation Sequencing, And Kaspar Genotyping In Development, Characterization, And Linkage Mapping Of Single Nucleotide Polymorphisms In The Grain Amaranths And Quinoa, Scott Matthew Smith

Theses and Dissertations

The grain amaranths (Amaranthus sp.) and quinoa (Chenopodium quinoa Willd.) are important seed crops in South America. These crops have gained international attention in recent years for their nutritional quality and tolerance to abiotic stress. We report the identification and development of functional single nucleotide polymorphism (SNP) assays for both amaranth and quinoa. SNPs were identified using a genome reduction protocol and next generation sequencing. SNP assays are based on KASPar genotyping chemistry and were detected using the Fluidigm dynamic array platform. A diversity screen consisting of 41 amaranth accessions showed that the minor allele frequency (MAF) of the amaranth …

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Transcriptome And Methylation Analysis Of Gossypium Petal Tissue, Aditi Rambani Dec 2012

Transcriptome And Methylation Analysis Of Gossypium Petal Tissue, Aditi Rambani

Theses and Dissertations

Polyploidization instantly doubles all genome content by combining two genomes that have markedly different methylation and gene expression levels. This process may be accompanied by genetic and epigenetic changes in each genome. Sequencing of the transcriptome (RNA-seq) and the methylome (bisulfite treated libraries whole genome libraries) were used to measure gene expression and methylation levels of genic regions of allopolyploid cotton petals and petals of their diploid relatives. Many differentially expressed genes detected by RNA-seq were consistent with expression levels previously detected by microarrays. RNA-seq results also reconfirmed the presence of general polyploid gene expression trends like expression level dominance …

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Transcriptome Analysis Of Drought Induced Stress In Chenopodium Quinoa, Joshua Arthur Raney Dec 2012

Transcriptome Analysis Of Drought Induced Stress In Chenopodium Quinoa, Joshua Arthur Raney

Theses and Dissertations

RNA-seq transcriptome analysis of Chenopodium quinoa at different water treatment levels was conducted in a greenhouse study using four water treatments (field capacity to drought) on a valley ecotype quinoa (variety Ingapirca) and an Altiplano Salares ecotype quinoa (variety Ollague). Physiological results support the earlier findings that the Salares ecotypes display greater tolerance to drought-like stress conditions than the valley ecotypes (as determined by growth rate, photosynthetic rate, stomatal conductance, and stem water potential). cDNA libraries from root tissue sample for each treatment x variety combination were sequenced using Illumina Hi-Seq technology in an RNA-seq experiment. De novo assembly of …

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Thin Soils And Sacbes: The Soil Resources Of Uci, Yucatan, Mexico, Zachary S. Larsen Dec 2012

Thin Soils And Sacbes: The Soil Resources Of Uci, Yucatan, Mexico, Zachary S. Larsen

Theses and Dissertations

The objective of this study was to use pedological evidence in conjunction with Geographic Information Systems, and soil physical and chemical analyses as means to better understand the agricultural landscape surrounding the ancient Maya city of Uci. Specifically, the query of this thesis is to determine whether there is an association between settlement density and soil resources, and what relationship if any there is between the ancient sacbe of Uci and its surrounding agricultural potential. Stable carbon isotope analysis of the humin fraction of the soil organic matter was conducted on several profiles from karst depressions known as rejolladas near …

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Cultural Thinning Of Native Sagebrush Stands To Increase Seed Yields, Kurt David Elder Dec 2012

Cultural Thinning Of Native Sagebrush Stands To Increase Seed Yields, Kurt David Elder

Theses and Dissertations

Wyoming big sagebrush (Artemisia tridentata Nutt.) is an important native shrub in the Great Basin because of its wide distribution where it dominates over 60 million ha and provides essential habitat and forage for many varied species. The hand collection of sagebrush seed often results in seed scarcity and the available seed quantities are at times inadequate to revegetate large areas that have been disturbed, resulting in a demand for sagebrush seed. Study locations were selected near Scipio and Sahara sand dunes of Utah, and treatments were 1-) control, no treatment applied area left undisturbed 2-) general chemical strip …

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Improving Phosphorus Use Efficiency Through Organically Bonded Phosphorus, Micheal W. Hill Dec 2012

Improving Phosphorus Use Efficiency Through Organically Bonded Phosphorus, Micheal W. Hill

Theses and Dissertations

Current maximum efficiency of phosphorus (P) fertilizers that is utilized by plants in the same year of application ranges from near zero to thirty percent. Despite low utilization of P in crop production, yields are often limited by P deficiencies. Innovative technology is requisite to achieve greater efficiency as fertilizer demands are increasing, while phosphorus mineral resources are rapidly being depleted. A growing environmental concern for nutrient pollution of surface waters also carries significant weight. A novel new product, Carbond® P, is promising technology to increase P use efficiency. Research is needed to understand its capabilities and the functioning mechanisms …

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A Survey Of Invasive Exotic Ants Found On Hawaiian Islands: Spatial Distributions And Patterns Of Association, Camie Frandsen Martin Dec 2012

A Survey Of Invasive Exotic Ants Found On Hawaiian Islands: Spatial Distributions And Patterns Of Association, Camie Frandsen Martin

Theses and Dissertations

An intensive sampling of all ant species encountered on 6 Hawaiian Islands: Big Island, Maui, Oahu, Kauai, Molokai, and Lanai took place between 1988 and 1996. Species presence and absence was recorded at each site. Using remote sensing, variables were added insitu and used throughout my analysis. Species accumulation curves suggest that sampling was comprehensive. There is a significant trend between island area and species richness which validates the Theory of Island Biogeography for invasive species. Islands were found to be significantly nested by area, order, and tourism. Cluster analysis shows a link between elevation, land-use and island, and species …

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Summer Watering Patterns Of Mule Deer And Differential Use Of Water By Bighorn Sheep, Elk, Mule Deer, And Pronghorn In Utah, Andrew V. Shields Dec 2012

Summer Watering Patterns Of Mule Deer And Differential Use Of Water By Bighorn Sheep, Elk, Mule Deer, And Pronghorn In Utah, Andrew V. Shields

Theses and Dissertations

Changes in the abundance and distribution of free (drinking) water can influence wildlife in arid regions. In the western USA, free water is considered by wildlife managers to be important for bighorn sheep (Ovis canadensis), elk (Cervus elaphus), mule deer (Odocoileus hemionus), and pronghorn (Antilocapra americana). Nonetheless, we lack information on the influence of habitat and landscape features surrounding water sources, including wildlife water developments, and how these features may influence use of water by sexes differently. Consequently, a better understanding of differential use of water by the sexes could influence the conservation and management of those ungulates and water …

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Habitat Selection Of Greater Sage-Grouse Centrocercus Urophasianus And Northern River Otters Lontra Canadensis In Utah, Matthew D. Westover Dec 2012

Habitat Selection Of Greater Sage-Grouse Centrocercus Urophasianus And Northern River Otters Lontra Canadensis In Utah, Matthew D. Westover

Theses and Dissertations

Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed imagery, we proceeded to 1) determine which features of brood-rearing habitat could be identified using widely available, fine-scale imagery 2) assess the scale at which sage-grouse selected brood-rearing habitat in our study area, and 3) create a predictive habitat model that could be applied across our large study area to …

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Alteration Of Behavior By Desert Bighorn Sheep From Human Recreation And Desert Bighorn Sheep Survival In Canyonlands National Park: 2002 - 2010, Kanalu K. Sproat Dec 2012

Alteration Of Behavior By Desert Bighorn Sheep From Human Recreation And Desert Bighorn Sheep Survival In Canyonlands National Park: 2002 - 2010, Kanalu K. Sproat

Theses and Dissertations

Human encroachment into wilderness areas can influence the persistence of wildlife populations by decreasing and degrading habitat, displacement, and decreasing survival. For bighorn sheep (Ovis canadensis), some human activities are detrimental, causing both physiological stress and habitat abandonment. Between 1979 and 2000, human recreation has increased over 300% in areas occupied by desert bighorn sheep (O. c. nelsonii) in southeastern Utah. We investigated if an increase in human activity in areas used by bighorns affected their behavior. We observed 34 bighorn sheep using focal-animal sampling for >14 hrs to compare time spent grazing and scanning between areas of high and …

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Effectiveness Of Phosphorus Fertilizers In Hydroponics And Glasshouse Settings With Moderate And High Organic Matter Soils, Jeffrey Sean Christian Summerhays Aug 2012

Effectiveness Of Phosphorus Fertilizers In Hydroponics And Glasshouse Settings With Moderate And High Organic Matter Soils, Jeffrey Sean Christian Summerhays

Theses and Dissertations

Phosphorus (P) is poorly soluble in most soils and, thus, has poor plant uptake efficiency. AVAIL® and Carbond P (CBP) are new fertilizer products shown to increase P use efficiency (PUE) and increase crop yields when grown in P limiting soils. Carbond P has specifically been seen to increases P uptake and crop yields in soils low in P, although effectiveness in regards to soil organic matter is unknown. The objectives of these studies were to determine if the mode of action for these products is related to physiological response, to determine if Carbond P is toxic to plant roots …

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Characterization And Variable Expression Of The Cslf6 Homologs In Oat (Avena Sp.), Melissa A. Coon Aug 2012

Characterization And Variable Expression Of The Cslf6 Homologs In Oat (Avena Sp.), Melissa A. Coon

Theses and Dissertations

(1,3;1,4)-β- D-glucan (β-glucan) is a plant cell wall hemicellulose and a main component of endosperm cell walls. The Cellulose Synthase F family of genes is involved in the synthesis of β-glucan. In this study full-length genomic sequences of CslF6 were obtained from multiple Avena species. Three unique alleles were found in each A. sativa line. Comparisons of these alleles to diploid Avena species allowed for identification of the genomic origin of each allele. The A and D genome alleles had identical amino acid sequences while the C-genome had 13 different amino acids. Global expression of CslF6 was completed at three …

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Translocation Mortality And Local, Regional, And Continental Diet Of The Northern River Otter (Lontra Canadensis), Casey Craig Day Aug 2012

Translocation Mortality And Local, Regional, And Continental Diet Of The Northern River Otter (Lontra Canadensis), Casey Craig Day

Theses and Dissertations

The northern river otter (Lontra canadensis) is a semi-aquatic carnivore whose range extends throughout most of the United States and Canada. The northern river otter experienced a severe range contraction post-European settlement, but due to widespread management has in recent decades begun to recover much of its former range and habitat. We translocated 27 river otters from Utah and Idaho to the Provo River, Utah from November 2009 through January 2012 in a reintroduction effort to restore the northern river otter to its native range. Of these 27 otters, 6 died as a result of effects related to the translocation. …

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Plant Establishment And Soil Microenvironments In Utah Juniper Masticated Woodlands, Kert R. Young Jul 2012

Plant Establishment And Soil Microenvironments In Utah Juniper Masticated Woodlands, Kert R. Young

Theses and Dissertations

Juniper (Juniperus spp.) encroachment into sagebrush (Artemisia spp.) and bunchgrass communities has reduced understory plant cover and allowed juniper trees to dominate millions of hectares of semiarid rangelands. Trees are mechanically masticated or shredded to decrease wildfire potential and increase desirable understory plant cover. When trees are masticated after a major increase in tree population density and associated decrease in perennial understory cover, there is a risk that invasive annual grasses will dominate because they are highly responsive to the increased resource availability that commonly follows removal of the main resource user. To determine if tree mastication increases …

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Post-Fire Soil Water Repellency: Extent, Severity And Thickness Relative To Ecological Site Characteristics Within Piñon-Juniper Woodlands, Daniel Lewis Zvirzdin Jun 2012

Post-Fire Soil Water Repellency: Extent, Severity And Thickness Relative To Ecological Site Characteristics Within Piñon-Juniper Woodlands, Daniel Lewis Zvirzdin

Theses and Dissertations

Erosion and weed dominance often limit the recovery of burned piñon-juniper woodlands. Soil water repellency (SWR) is one factor that may contribute to this by increasing overland flow and impeding seedling establishment. In spite of these effects, the extent of SWR within piñon-juniper woodlands is unknown. In this study, the extent, severity and thickness of SWR were sampled across 41 1,000 m2 plots within three 2009 Utah wildfires. Predictive models of SWR were built from ecological site characteristic data collected at each site. Across the study, SWR was found at 37% of the points sampled. SWR extent was strongly related …

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Plant-Soil Feedbacks And Subalpine Fir Facilitation In Aspen-Conifer Forests, Joshua R. Buck Mar 2012

Plant-Soil Feedbacks And Subalpine Fir Facilitation In Aspen-Conifer Forests, Joshua R. Buck

Theses and Dissertations

This thesis includes two studies. The first study examined changes in soil characteristics as a result of prolonged conifer dominance in successional aspen-conifer forests. Changing disturbance patterns in aspen-conifer forests appear to be altering successional dynamics that favors conifer expansion in aspen forests. The primary objective of this paper was to identify how increasing conifer dominance that develops in later successional stages alters forest soil characteristics. Soil measurements were collected along a stand composition gradient: aspen dominated, aspen-conifer mix, conifer dominated and open meadow, which includes the range of conditions that exists through the stages of secondary succession in aspen-conifer …

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An Object-Based Image Analysis Of Treated And Untreated Pinyon And Juniper Woodlands Across The Great Basin, April Hulet Mar 2012

An Object-Based Image Analysis Of Treated And Untreated Pinyon And Juniper Woodlands Across The Great Basin, April Hulet

Theses and Dissertations

Land managers need to rapidly assess vegetation composition and bare ground to effectively evaluate, manage, and restore shrub steppe communities that have been encroached by pinyon and juniper (P-J) trees. A major part of this process is assessing where to apply mechanical and prescribed fire treatments to reduce fuel loads and maintain or restore sagebrush steppe rangelands. Geospatial technologies, particularly remote sensing, offers an efficient option to assess rangelands across multiple spatial scales while reducing the need for ground-based sampling measurements. High-spatial resolution color-infrared imagery (0.06-m pixels) was acquired for sagebrush steppe communities invaded by P-J trees at five sites …

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Cheatgrass (Bromus Tectorum), Native Grasses, And Small Mammals In The Great Basin: A Test Of The Apparent Competition Hypothesis Facilitated By A Novel Method Of Decanting Seeds From A Flotation Solution, Jacob Elias Lucero Mar 2012

Cheatgrass (Bromus Tectorum), Native Grasses, And Small Mammals In The Great Basin: A Test Of The Apparent Competition Hypothesis Facilitated By A Novel Method Of Decanting Seeds From A Flotation Solution, Jacob Elias Lucero

Theses and Dissertations

The effect of shared enemies between invasive and native species has been argued to facilitate biological invasions (i.e., the apparent competition hypothesis or ACH). This study investigated a previously untested possibility: whether granivorous small mammals facilitate cheatgrass (Bromus tectorum) invasion by driving food-mediated apparent competition between cheatgrass and native grasses. Specifically, we tested three predictions that must be true if such apparent competition occurs. First, cheatgrass invasion augments total seeds available to granivorous small mammals. Second, density of granivorous small mammals increases in response to increased seed availability (simulated with experimental additions of cheatgrass seeds). Third, granivorous small …

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Seasonal Habitat Selection By Greater Sage Grouse In Strawberry Valley Utah, Riley D. Peck Dec 2011

Seasonal Habitat Selection By Greater Sage Grouse In Strawberry Valley Utah, Riley D. Peck

Theses and Dissertations

This study examined winter habitat use and nesting ecology of greater sage grouse (Centrocercus urophasianus) in Strawberry Valley (SV), Utah located in the north-central part of the state. We monitored sage grouse with the aid of radio telemetry throughout the year, but specifically used information from the winter and nesting periods for this study. Our study provided evidence that sage grouse show fidelity to nesting areas in subsequent years regardless of nest success. We found only 57% of our nests located within the 3 km distance from an active lek typically used to delineate critical nesting habitat. We …

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Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist Dec 2011

Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist

Theses and Dissertations

Feral horse management has become a subject of significant controversy in the United States. This is because of differing opinions and minimal recent empirical data on feral horses. In recent years, numbers of feral horses have increased due to governmental horse removal restrictions (specifically the Wild Horse and Burro act of 1971). With increasing numbers of feral horses on rangelands, land managers are challenged with identifying the appropriate course of action for satisfying groups with differing opinions. The purpose of this study is to characterize diet consumption through the use of stable isotope dietary analysis (δ15N and δ13C). We did …

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Geochemical Analysis Of Ancient Activities At Two Plazas In Cobá, Mexico, Eric G. Coronel Dec 2011

Geochemical Analysis Of Ancient Activities At Two Plazas In Cobá, Mexico, Eric G. Coronel

Theses and Dissertations

Two plazas at Cobá, Mexico, may have been the place of market activity during the classic Maya period. The intense decomposition in the warm, moist soils of the Yucatan Peninsula precludes the identification of organic artifacts in archaeological contexts, but phosphorus and trace elements accumulation in soils may provide evidence of marketing activities. The spatial patterns of P and trace element concentrations were used to elucidate the types of ancient Maya activities that took place in those plazas. Phosphorus concentrations are highly correlated (p-value <0.01) with Fe, Mn, and Zn levels in both Plaza B and D. Although the soil geochemistry of Plaza B does not show a marketplace pattern in comparison with previous studies, the elemental concentrations and distributions within Plaza D join other lines of evidence to support the premise that marketplace activities took place at that location. Soil samples were analyzed using DTPA extraction, Mehlich II, Olsen, and Portable X-Ray Fluorescence (PXRF). Experiments were performed to study the suitability of PXRF for field studies. Aspects that were studied include granule size, soil moisture content, protective plastic films that could interfere with the X-Ray signal when placing the samples on top of the analyzer, and a comparison of certified soil standards to the PXRF elemental concentration readings. The results suggest that a field laboratory could be set up to air-dry and sieve soil samples to a minimum mesh size of #10 (> 2 mm).

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Scarification And Cultural Practice Of Four Lupine Species Native To The Great Basin, Covy Dennis Jones Aug 2011

Scarification And Cultural Practice Of Four Lupine Species Native To The Great Basin, Covy Dennis Jones

Theses and Dissertations

The Great Basin is North America's largest desert, encompassing 135 million acres. Grazing and other anthropogenic activities in the Great Basin have put heavy demands on the landscape over the last 150 years. Heavily grazed areas lack diversity which allows the spread of exotic weed species. Cheatgrass (Bromus tectorum L [Poaceae]) has invaded and shortened fire frequency intervals from historic 30—100 years to as few as three to five years. Post-fire reseeding of native species is requisite for restoration of highly invaded ecosystems thus, preventing complete conversion to exotic weeds. Most native shrubs and grasses are available for restoration …

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Oat Snp Marker Discovery And Mapping Based On 454 Pyrosequencing Of Genome-Reduced Avena Magna Murphy Et Terrell, Rachel Rebecca Redman Jul 2011

Oat Snp Marker Discovery And Mapping Based On 454 Pyrosequencing Of Genome-Reduced Avena Magna Murphy Et Terrell, Rachel Rebecca Redman

Theses and Dissertations

The size and complexity of the oat genomes (Avena L., x = 7) have made genetic studies, including the discovery of molecular markers, difficult. Recent attention to these species has resulted in the development of many DArT -based markers in the tetraploid A. magna Murphy et Terrill (2n = 28, CCDD genomes), along with numerous RFLP's, SSR's, DArT's, and EST-based SNPs in hexaploid A. sativa L. (2n = 42, AACCDD). Here we report the first SNP markers for tetraploid oat based on genome reduction and high-throughput pyrosequencing in two inbred lines of A. magna: A-169 (wild) and Ba …

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Marker Discovery In Allotetraploid Cotton Using 454 Pyrosequencing, Robert L. Byers Jul 2011

Marker Discovery In Allotetraploid Cotton Using 454 Pyrosequencing, Robert L. Byers

Theses and Dissertations

A narrow germplasm base and a complex allotetraploid genome have historically made the discovery of single nucleotide polymorphism (SNP) markers difficult in cotton (Gossypium hirsutum). We conducted a genome reduction experiment to identify SNPs from two accessions of G. hirsutum and two accessions of G. barbadense. Approximately 2 million sequence reads were assembled into contigs with an N50 of 508 bp and analyzed for SNPs. A total of 11,834 and 1,679 SNPs between the accessions G. hirsutum and G. barbadense, respectively, were identified with highly conservative parameters (a minimum read depth of 8x at each SNP …

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Reproductive Success And Soil Seed Bank Characteristics Of Astragalus Ampullarioides And A. Holmgreniorum (Fabaceae): Two Rare Endemics Of Southwestern Utah, Allyson B. Searle Jul 2011

Reproductive Success And Soil Seed Bank Characteristics Of Astragalus Ampullarioides And A. Holmgreniorum (Fabaceae): Two Rare Endemics Of Southwestern Utah, Allyson B. Searle

Theses and Dissertations

Astragalus ampullarioides and A. holmgreniorum are two rare endemics of southwestern Utah. Over two consecutive field seasons (2009-2010) we examined pre-emergent reproductive success, based on F/F and S/O ratios, from populations of both Astragalus ampullarioides and A. holmgreniorum, estimated the density of the soil seed bank of A. holmgreniorum as a measure of potential post-emergent reproductive success, and estimated seed persistence within the soil seed bank. Fruit/flower (F/F) ratios and seed/ovule (S/O) ratios varied significantly between populations and among years in both species, and showed low reproductive output in both taxa. In Astragalus ampullarioides F/F and S/O were 0.06±0.01 …

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Evaluating Nutrient Availability In Low Fertility Soils With Resin Capsules And Conventional Soil Tests, Mary Pletsch Jones Jul 2011

Evaluating Nutrient Availability In Low Fertility Soils With Resin Capsules And Conventional Soil Tests, Mary Pletsch Jones

Theses and Dissertations

Commonly used soil analysis and resin capsule procedures are used to assess nutrient status in fertile soils, but their validity in semi-arid ecosystems is unknown. Three studies were performed to assess resin capsule effectiveness in semi-arid ecosystems. An incubation study was completed in which loamy sand and sandy clay loam soils were treated with rates of N, P, Fe and Zn. Each soil treatment was implanted with a resin capsule and incubated for 60 or 120 days. Resin capsules reflected NH4-N and P fertilizer at low rates in the loamy sand. NO3-N reflected rates in both soils, but did not …

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Genome Snapshot And Molecular Marker Development In Penstemon (Plantaginaceae), Rhyan B. Dockter Jul 2011

Genome Snapshot And Molecular Marker Development In Penstemon (Plantaginaceae), Rhyan B. Dockter

Theses and Dissertations

Penstemon Mitchell (Plantaginaceae) is one of the largest, most diverse plant genera in North America. Their unique diversity, paired with their drought-tolerance and overall hardiness, give Penstemon a vast amount of potential in the landscaping industry—especially in the more arid western United States where they naturally thrive. In order to develop Penstemon lines for more widespread commercial and private landscaping use, we must improve our understanding of the vast genetic diversity of the genus on a molecular level. In this study we utilize genome reduction and barcoding to optimize 454-pyrosequencing in four target species of Penstemon (P. cyananthus, …

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