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Use Of Plant Growth Regulators To Expand The Period Of Sagebrush Seed Germination And Reduce The Risk Of Restoration Failure: Laboratory Trials, Chelsea Elizabeth Keefer

Theses and Dissertations

Seed germination during unhospitable environmental conditions can be a major barrier to direct seeding efforts in dryland systems. In the sagebrush steppe, Artemisia tridentata Nutt. ssp. wyomingensis and Artemisia arbuscula are important shrub species that are being used in restoration, but seeding success is highly sporadic due to inter-annual and intra-seasonal weather variability. Altering and expanding the period of germination, as a form of bet-hedging, may improve plant establishment. Our objective was to determine if we could expand the period of germination using plant growth regulators (PGRs) applied in a conglomerated seed coating treatment. In a laboratory study, the seed …

Whole-Genome Assembly Of Atriplex Hortensis L. Using Oxfordnanopore Technology With Chromatin-Contact Mapping, Spencer Philip Hunt

Theses and Dissertations

Atriplex hortensis (2n = 2x = 18, 1C genome size ~1.1 gigabases), also known as garden orach, is a highly nutritious, broadleaf annual of the Amaranthaceae-Chenopodiaceae family that has spread from its native Eurasia to other temperate and subtropical environments worldwide. Atriplex is a highly complex and polyphyletic genus of generally halophytic and/or xerophytic plants, some of which have been used as food sources for humans and animals alike. Although there is some literature describing the taxonomy and ecology of orach, there is a lack of genetic and genomic data that would otherwise help elucidate the genetic variation, phylogenetic position, …

Hydrologic And Biologic Responses Of Anthropogenically Altered Lentic Springs To Restoration In The Great Basin, Leah Nicole Knighton

Theses and Dissertations

Water is a limited and highly valued resource in the semi-arid Great Basin. Surface water sources are often small and widely spaced apart, comprising only 1-3% of the surface area of the overall landscape. Despite their small size, these springs and surrounding wet meadows have a substantial effect on the surrounding environment. Springs provide drinking water, forage and cover for livestock and wildlife, habitat for diversity of plant species and a resource for human-related activities. In recent years, many of these springs have become dewatered due to diversions of groundwater for municipal water and agriculture, and climatic shifts in precipitation …

The Effect Of Chenopodium Quinoa On Salinization Levels In Soil, Angel Mirae Morris, P. Jeff Maughan, Bryan G. Hopkins, Neil Hansen

Journal of Undergraduate Research

Chenopodium quinoa is native to the Peruvian Andes and has been an important food crop for more than 5,000 years. C. quinoa can adapt to a wide variety of climates and altitudes, making it a viable food source for areas of the world that have little rainfall or experience dramatic seasonal changes in temperature. Further, according to a study conducted in 20161, quinoa was found to be extremely salt tolerant without detriment to the grain. High salinity tolerance suggests that planting quinoa may potentially improve soil conditions, however, little research has been conducted on the bioremediation effects of C. quinoa. …

Remote Sensing Approaches To Improve Water And Nitrogen Management Of Kentucky Bluegrass (Poa Pratensis), Austin Hopkins, Dr. Neil C. Hansen

Journal of Undergraduate Research

This project identifies remote sensing practices to conserve water by optimizing nitrogen (N) fertilization and irrigation strategies. Turfgrass is the most irrigated crop by area (163,800 km2 ), accounting for 1.9% of the continental U.S. This causes negative environmental impacts and puts the future of irrigated turfgrass in question due to increasing water scarcity, especially in the western U.S. More information is needed on how to irrigate in droughts and water limited areas as turf provides significant benefits in our environment such as aesthetics, cooling effects, carbon sequestration, and preventing soil erosion.

Addressing The Global Eutrophication Crisis From The Ground Up: Quantifying Ecosystem Resilience To Nutrient Loading, Rebeccas Frei, Banjamin Abbott

Journal of Undergraduate Research

I conducted a project assessing the components of aquatic ecosystems to characterize their resilience to ever-increasing nutrient pollution. Since the Industrial Revolution, humans have more than doubled nitrogen inputs, and quintupled phosphorus inputs. Some of these nutrients run off into streams and rivers, resulting in an overabundance of nutrients, a state called eutrophication. Major threats of eutrophication include toxic algal blooms and waterbody oxygen depletion, which kill aquatic life, harm local economies, threaten human health, and endanger water security.

A Metagenomic Approach To Understand Stand Failure In Bromus Tectorum, Nathan Joseph Ricks

Theses and Dissertations

Bromus tectorum (cheatgrass) is an invasive annual grass that has colonized large portions of the Intermountain west. Cheatgrass stand failures have been observed throughout the invaded region, the cause of which may be related to the presence of several species of pathogenic fungi in the soil or surface litter. In this study, metagenomics was used to better understand and compare the fungal communities between sites that have and have not experienced stand failure. Samples were taken from the soil and surface litter in Winnemucca, Nevada and Skull Valley, Utah. Results show distinct fungal communities between Winnemucca and Skull Valley, as …

The Genome Of Cañahua: An Emerging Andean Super Grain, Hayley Jennifer Mangelson

Theses and Dissertations

Chenopodium pallidicaule, known commonly as cañahua, is a semi-domesticated crop grown in high-altitude regions of the Andes. It is an A-genome diploid (2n = 2x = 18) relative of the allotetraploid (AABB) Chenopodium quinoa and shares many of its nutritional benefits. Both species contain a complete protein, a low glycemic index, and offer a wide variety of nutritionally important vitamins and minerals. Due to its minor crop status, few genomic resources for its improvement have been developed. Here we present a fully annotated, reference-quality assembly of cañahua. The reference assembly was developed using a combination of established techniques, including multiple …

Evaluating Nitrogen And Carbon Differences In Standing Litter From Normal And Prematurely Senesced Bromus Tectorum Plants, Alexa Lunt Jensen

Theses and Dissertations

Bromus tectorum, an invasive winter annual, has displaced native vegetation throughout the western United States. Bromus tectorum litter influences nutrient cycling near the soil surface as well as plant establishment. Failed seed production of B. tectorum occasionally occurs in the field, with plants exhibiting weak flowering culms that turn straw-colored in spring when normal plants are green or purple in color. Because annual grasses transport most soluble carbon (C) and nitrogen (N) to reproductive organs, seed production failure results in significantly different fates for these nutrients compared with normal plants. As part of larger efforts to understand events leading to …

The Effects Of Dixie Harrow Treatments On Greater Sage-Grouse Resource Selection And The Nutritional Value Of Sagebrush During Winter, Jason Alan Wood

Theses and Dissertations

Sagebrush (Artemisia spp.) is an important source of food and cover for many animals, especially during winter months. Understanding how wildlife species respond to sagebrush management actions can help improve conservation planning. Dixie harrow is a method of improving spring/summer habitat for many herbivores by reducing sagebrush cover to stimulate the growth of grasses and forbs. These treatments, however, may influence the quantity and quality of sagebrush available to greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) during winter. We evaluated the effects of Dixie harrow on sage-grouse resource selection during winter (Chapter 1) and on the nutritional value of sagebrush (Chapter …

Impacts Of Novel Fire And Herbivory Regimes On Snow-Waterresources And Resilience Of Aspen Forests, Jordan Daniel Maxwell

Theses and Dissertations

Human activities and expansion have created novel disturbance patterns across Earth’s landscapes. Disturbance is an ecological interruption after which ecosystem recovery or transition into a new state can occur, affecting biodiversity, ecosystem functioning, and theavailability of ecosystem services. Fire and herbivory are two of the most widespread forces of disturbance which shape ecosystems globally. In temperate forest ecosystems, fire affects forest composition, which influences the diversity and resilience of ecosystems (chapters 1 and 2) and forest canopy structure, which is important to snowpack accumulation and the availability of water resources (chapters 3 and 4). In chapter one, the effects of …

Evaluating Fungal Pathogen Inoculum Loads In Field Seed Banks, Taryn Lori Williamson

Theses and Dissertations

Quantification of soilborne pathogen inoculum loads is important in both agricultural and wildland settings. Quantitative Polymerase Chain Reaction (qPCR) methods using SYBR Green chemistry have been shown to be useful for quantifying fungal inoculum loads in environmental samples. The purpose of this study was to develop a method to quantify fungal pathogen inoculum loads in soil seed banks using a qPCR method with SYBR Green chemistry. The invasive annual grass Bromus tectorum was chosen for this seed bank study. There were three objectives: 1) to design target-specific primers for three fungal pathogens known to be important in Bromus tectorum seed …

Effectiveness Of The Smallholder Sustainability Assessment Of Food And Agricultural Systems App For Subsistence Farm Systems In Ecuador, Carter D. Allred, H. L. Boman, S. J. Clawson, C. A. Freestone, S. N. Hockett, C. A. Holden, E. R. Phipps, C. N. Quigley, M. M. Rupard, N. C. Hansen

Library/Life Sciences Undergraduate Poster Competition 2019

Small-scale agriculture is the primary source of food for the majority of the developing world. It is a vital component of the total global land usage for agricultural production, and sustaining and improving subsistence farms is critical for meeting global food demand as well as maintaining the integrity of agro-ecological systems. Due to the important role that smallholder farmers play in global agriculture, the Food and Agriculture Organization of the UN developed the Smallholder Sustainability Assessment of Food and Agricultural Systems App (SAFA), a 100-question survey tool created for simplicity and wide-reaching applicability. SAFA is flexible in nature in that …

Molecular Characterization Of Penstemon Scariosus (Plantaginaceae), Mikel R. Stevens

Journal of Undergraduate Research

The objectives of this project: Our objective was “to develop an understanding of the genetic structure of the varieties within P. scariosus. With a specific intent to test the hypothesis that P. scariosus var. albifluvis is distinct within P. scariosus” while mentoring no less than four undergraduate students. We have meet and exceeded the academic objectives proposed and then funded by this MEG as attested to in the following paragraphs and attachments to this report. As a result of our most excellent success in this project we have four additional students who are volunteering on the project. It is our …

Characterizing Endophyte Interactions That Enhance Tolerance Of Water Stress And Disease In Economically And Culturally Important Succulent Crops, Agave And Yucca, Claire Poore, Ryan Stewart

Journal of Undergraduate Research

Agave and Yucca species are both cultural and economically important in the south western United States and Mexico. As desert plants, Agave and Yucca have adapted to hot and dry conditions and with increasing global temperatures, have the potential to fill even more important roles in modern agriculture¹. The Navajo people place immense value on Yucca due to its source for food, twine, hair cleanser as well and its role in religious ceremonies. Agave has long been valued as a crop in Mexico and is used for food, fiber and beverages. Fusarium oxysporum is a major plant disease …

Increases In Fresh Weight Yield From Low Tunnels And Nitrogen Fertilization In Opuntia (Cactus Pear, Nopal) Species In Utah, Kennedy Christian, Mena Nicolas, J. Ryan Stewart

Journal of Undergraduate Research

With the global human population spiraling upward and the intensity of climate-change-induced drought events increasing, there is a growing need for identifying and developing highly productive, stress-tolerant crops that can be cultivated in marginal lands (Yang et al., 2015). Species within the Opuntia genus exhibit several traits, which enable them to withstand drought while growing in nutrient-poor soils (Nobel, 2010). However, these Opuntia species lack sufficient cold hardiness to be produced beyond northern Mexico (Felker et al., 2006) despite an increase in consumer demand of these pads from the Intermountain West and other parts of the U.S (Huffcut, 2004). Our …

Increasing Water Use Efficiency By Nitrogen Management In Turfgrass, Austin Hopkins, Dr. Neil C. Hansen

Journal of Undergraduate Research

This project identifies turfgrass practices to conserve water by optimizing nitrogen (N) fertilization and irrigation strategies. Turfgrass is the most irrigated crop by area (163,800 km2), accounting for 1.9% of the continental U.S. This causes negative environmental impacts and puts the future of irrigated turfgrass in question due to increasing water scarcity, especially in the western U.S. More information is needed on how to irrigate in droughts as turf provides significant benefits in our environment such as aesthetics, cooling effects, carbon sequestration, and preventing soil erosion.

Composition Of The Community Of Small Mammals In The Great Basin Desert, Samantha Elizabeth Phillips

Theses and Dissertations

Small mammals are a keystone guild in arid ecosystems; often exhibiting top-down control of the diversity and structure of plant communities. However, changing climate, shifting fire regimes, and the invasion of exotic plants are modifying the structure of arid systems. Environmental changes in these arid systems are likely altering small mammal communities, and therefore, their ecological role. We examined two aspects of the community composition of small mammals in the Great Basin: changes in community composition since large scale sampling of the region began in 1930, and the current population of a sensitive species of small mammal, the dark kangaroo …

An Ecological And Distributional Analysis Of Great Basin Bristlecone Pine (Pinus Longaeva), Gregory Watson Taylor

Theses and Dissertations

Understanding the impacts of climate change is critical for improving the conservation and management of ecosystems worldwide. Ecosystems vary along a precipitation and temperature gradient, ranging from tropical jungles to arid deserts. The Great Basin is a semi-arid eco-region that is found within the western United States. Plant communities within the Great Basin range from sagebrush valleys to sub-alpine conifer forests found at high elevation areas. It is predicted that the Great Basin will experience prolonged periods of drought, more intense fires, and greater variability in average annual and monthly precipitation, all in response to changes in climate patterns. At …

Biochemical Characterization Of The Oat Cslf6 Mixed-Linkage Glucan Synthase, Alexander E. Chu, Eric N. Jellen

Journal of Undergraduate Research

The central dogma of molecular biology teaches that the information of life is stored in DNA, a linear chain of nucleotide molecules. The information in DNA nucleotides is then transcribed into RNA, which encodes the amino acids needed to make proteins. These chemically active proteins are responsible for nearly all the processes of life in the cell. Thus, a single gene, consisting of relatively inert DNA, can give rise to a protein with a highly specialized function, and the collection of genes contained in a genome can give rise to the diversity of biomolecular function needed to sustain a living …

A Metagenome-Wide Association Study Of Gut Microbiota In Drosophila Cancer Metastasis., Anthony Caruso, John Chaston

Journal of Undergraduate Research

It has been established by past scientific research that the gastrointestinal microbiome plays a defined role in many human diseases. Some of these diseases include inflammatory bowel disease, autism, hypertension, and even cancer. A common symptom seen in many of these diseases is the dysbiosis of intestinal microbiota. Studies investigating several of these ailments have shown that model organisms can be rescued from negative symptoms through the addition of health promoting bacteria to their gastrointestinal tracts. While these fascinating correlations between levels of gut microbiota and disease have been well established, the specific genes of the bacteria and the inter-organism …

Incorporating Ground Juniper Wood Into Sagebrush Seed Agglomerates As A Fungicide Alternative, Benjamin Hoose, Matthew Madsen

Journal of Undergraduate Research

Sagebrush seed agglomerates (referred to as ‘agglomerates’ in the remainder of the report) are small balls of seed, clay, and compost that allow us to treat sagebrush seeds with germination enhancers. The goal of my project was to determine whether we could use the antimicrobial properties of juniper wood to reduce fungal attack of sagebrush seed by replacing the compost component of agglomerates with ground juniper. We met our goal, and determined that juniper wood does not act as an effective fungal deterrent. However, we did successfully incorporate juniper into agglomerates, which added consistency and repeatability to the agglomerate recipe …

Bioactivity Of Secondary Metabolites Of The Alaskan Fungus, Phellinus Igniarius, Johnathon Kreider, Brad Geary

Journal of Undergraduate Research

Drug testing is one of the most important activities of the Life Sciences. As biotechnological resources like genetically modified mice or artificial skin become more commonplace and accessible to drug researchers, testing has become more efficient. One of the reoccurring problems, though, is that for new drugs to be tested they must first be found. Research has shown that plants and fungi are the best places to look: over 70 percent of drugs that have been introduced in the last quarter century have been derived from natural resources (Newman& Cragg 2012). Notable examples such as Taxol from the Yew tree, …

Microbiota Effects On Ethanol Tolerance In Drosophila Melanogaster, Rebekah Rushforth, John Chaston

Journal of Undergraduate Research

Drosophila melanogaster, the common fruit fly, is one of the primary organisms for genetic study because it contains a small genome that allows for easy study of mutations. Furthermore, Drosophila is a choice model for host genetics. The human gut microbiome contains hundreds to thousands of different species of microbiota; where the microbiota of a fruit fly is approximately 40 species. In addition, we can make the flies axenic (bacteria free). This allows us to mono or multi associate different bacteria groups in order to identify causation in phenotype changes in the host organism. In this project, we test axenic …

Exploration Of The Gossypium Raimondii Genome Using Bionano Genomics Physical Mapping Technology, Christopher Jon Hanson

Theses and Dissertations

Cotton is a crop with a large global economic impact as well as a large, complex genome. Most industrial cotton production is from two tetraploid species (Gossypium hirsutum L. and Gossypium barbadense L.) which contain two subgenomes, specifically the AT and DT subgenomes. The DT subgenome is nearly half the size of the AT subgenome in tetraploid cotton and is closely related to an extant D-genome Gossypium species, G. raimondii Ulbr. Characterization of the structural variants present in diploid D-genome should provide greater insight into the evolution of the DT subgenome in the tetraploid cotton. Bionano (BNG) optical mapping uses …

Characterizing The Spatial Variation Of Crop Water Productivity For Variable-Rate Irrigation Management, Jeffrey David Svedin

Theses and Dissertations

Irrigated agriculture is the primary consumer of limited worldwide freshwater resources. Drought, growing world populations, and environmental demands compete with irrigation for freshwater resources"”threatening sustainable global food, fuel, and fiber production. This escalating global crisis demands that agriculture produce more food using less water. Traditional irrigation management has used technology to apply uniform irrigation rates across landscapes"”ignoring natural environmental variation. This provides inherent inefficiencies of over- or under- irrigation within individual fields. Variable-rate irrigation (VRI) is modern technology that employs global positioning systems and geographic information systems to match irrigation to spatially variable crop water demands within a field. Although …

Plane Of Energy Nutrition On Blood Metabolites, Milk Production And Lamb Growth In Friesian Sheep, Rebekah Paige Jensen

Theses and Dissertations

Small ruminant species are utilized for their diverse products including meat, dairy products, and wool. Effective and humane management are essential to maintain high production rates and comfortable animals. To attain this objective, managers needs to have an extensive knowledge of husbandry techniques, understanding of physiological processes, and familiarity with nutritional requirements. We examined the effects of varying feed components on two different ruminal species. In Chapter 1, we conducted a study to evaluate"¯the effects"¯of a low metabolizable energy (LME) and high metabolizable energy (HME) diet on twenty-two Friesian/Lacuane"¯cross ewes and lamb nutritional status."¯Effects on milk production during early lactation …

Plant Functional Groups And Success In A Changing Environment: Modeling Physiological Niches Of Colorado Plateau Plants, Anne Thomas

Undergraduate Honors Theses

Quantifying the environmental and physiological niches of plant species is crucial to predicting their sensitivity to global change, and aggregating plant species by functional type is fundamental both to ecological theory and to the practicality of large-scale efforts to predict the consequences of global change. However, traditional functional types are not always predictive of individual species’ responses to change. Here, an inverse species distribution modeling approach is used to identify functionally similar species based on physiological niche in order to better anticipate the consequences of climate change on the Colorado Plateau, USA. The Colorado Plateau is a semiarid region particularly …

Microbial And Co2 Responses To Water Stresses Show Decreased Productivity And Diversity Through Time, David Michael Robinson

Theses and Dissertations

Some bacterial taxa when stimulated by water additions will break dormancy, grow, and become dominant members of the community and contribute significant pulses of CO₂ associated with the rewetting event. These pulses of activity are associated with high levels of bacterial productivity in soils. (Aanderud et al. 2011) We examined the bacterial taxa that resuscitate and become metabolically active following two forms of water stress (soil drying-rewetting and freeze-thaw cycles) and we captured and measured the CO₂ emanating from those soils. Specifically, We used target metagenomics, which uses a specific gene pool within bacteria that is associated with …

Landscape Foundations: A Practical & Technical Guide To Landscape Maintenance, Marco Crosland

Undergraduate Honors Theses

Many homeowners struggle to maintain healthy landscapes. Often, they simply don’t understand basic principles that, if followed, would make a significant difference in the health and appearance of their landscape. The hope of Landscape Foundations is to help homeowners maintain healthy and excellent landscapes by teaching these “correct principles”.

What makes Landscape Foundations different than other landscape guides is that it brings in current research and explains it in a simple way. This guidebook provides pictures and additional resources to explain landscape maintenance principles. It teaches both the practical and technical sides.

Landscape Foundations is written for both beginners and …