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Plant-Plant Interaction In Early- Vs. Late-Successional Varieties Of The Hawaiian Landscape-Dominant Tree, Metrosideros Polymorpha, Tomoko Sakishima

UNLV Theses, Dissertations, Professional Papers, and Capstones

Plant-plant interactions play an important role in assembling plant communities. Interactions between neighboring plants can vary as a result of the genetic relatedness of neighbors, impacting rates of growth and patterns of resource allocation. When growing alongside close relatives, some species decrease their growth in a form of cooperation, while others grow faster through facilitation. A complication of plant interaction studies arises because decreased growth in the presence of close relatives can also be due to competition for resources, which increases with phenotypic similarity. Further complicating matters, mycorrhizal fungi, through their connections with plant roots, may strongly influence plant interactions. …

Contrasting Nitrogen Sources Impact Nitrogen Use Efficiency And Soil Health Under Silage Corn Production In A Semi-Arid Environment, Phearen Kit Miller

All Graduate Theses and Dissertations, Fall 2023 to Present

Silage corn production challenges sustainable intensification and soil health in semi-arid environments because the entire aboveground biomass is harvested and removed from the field. An irrigated silage corn field study was conducted over a decade comparing nitrogen fertility sources using a complete randomized block design with four treatments: control with no nitrogen fertilizer (control), low ammonium sulfate at 112 kg N ha⁻¹ (AS100), high ammonium sulfate at 224 kg N ha⁻¹ (AS200), and steer manure compost at 224 kg total N ha⁻¹ (compost). Research focused on the impact of these contrasting nitrogen sources on silage corn production, …

Morphological And Physio-Biochemical Responses And Gene Expression Analyses Of Landscape Plants Under Salinity Stress, Asmita Paudel

All Graduate Theses and Dissertations, Fall 2023 to Present

Soil salinity is a significant global issue that adversely impacts the growth and development of landscape plants. One of the effective strategies to prevent salinity damage to landscape plants is to cultivate species that are tolerant to the prevailing salinity levels. Salinity tolerance varies among plant species and cultivars. Therefore, this research aimed to investigate the salinity tolerance of nine landscape plants [Albizia julibrissin (mimosa tree), Arctostaphylos uva-ursi (kinnikinnick), Cercocarpus ledifolius (curl-leaf mountain mahogany), Cercocarpus montanus ‘Coy’ (alder-leaf mountain mahogany), Penstemon barbatus ‘Novapenblu’ (rock candy blue^® penstemon), Penstemon strictus ‘Rocky Mountain’ (rocky mountain beardtongue), Punica granatum ‘Wonderful’ (pomegranate), …

Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti

All Graduate Theses and Dissertations, Fall 2023 to Present

Growing nursery plants in containers requires a timely supply of mineral nutrients for optimum growth. However, there is a misconception among growers that the application of higher doses of fertilizers hastens plant growth; instead, it can lead to runoff and leaching loss of nutrients. Reducing fertilizer application while sustaining healthy plants can not only negate environmental consequences but also save fertilizer costs. For example, two ground covers, Lysimachia nummularia (creeping jenny, moneywort) and Vinca minor 'Bowles' (periwinkle), can be grown for three months by applying 6 mg/L of phosphorus (P) as reduction of P to single application of 6 mg/L …

Nutrient Management Of Cannabis In Controlled Environments, Julie A. Hershkowitz

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis has been cultivated for millennia as a multipurpose crop for food, fiber, and medicine. Secondary metabolites called cannabinoids, including cannabidiol (CBD) and the psychoactive Δ-9 tetrahydrocannabinol (Δ-9 THC), are responsible for the medicinal properties of cannabis. The intoxicating nature of THC resulted in legislation prohibiting the possession and production of cannabis within the United States during the 20^th century. As a result, research programs on cannabis production were halted at most institutions. In recent years, cannabis production has become widespread within the US as a result of increasing legalization. However, modern cannabis production nutrient management programs often include …

Analysis Of Water Pollutants Across Greater Omaha, Desmond Marshall

Theses/Capstones/Creative Projects

Water is a finite resource, and most water has the potential to become contaminated in sitting bodies. Health complications have an increased chance of occurring when these water sources have pollutants. Preventative and treatment methods are components of the legislation put in place to prevent concentrations from reaching levels capable of causing these ailments. However, sites sometimes fail to keep them under tolerated levels. This study is intended to examine if several locations across Omaha are keeping pollutants under legal concentrations and analyze any trends in the data. Locations (n=10) are sampled twice, with exactly two-weeks between collections. The water …

Effects Various Distilled Water Brands Have On Chlorophytum Comosum., Brooke Bluhm

Theses/Capstones/Creative Projects

When first attempting home gardening, one of the challenges many home-renters are starting to face is being able to supply enough clean water to one’s plants. In order to overcome this challenge, many plant enthusiasts are utilizing prepackaged distilled water from price friendly brands available at most regional Walmart locations. With the number of choices available on the shelves of today’s grocery stores, and vague ingredient lists on packaging it can be challenging to determine which brand is actually best suited for one’s specific needs. In order to determine the best distilled water suited to grow Chlorophytum comosum, various gallons …

How Is International Orchid Trade Regulated, And How Effective Are Those Regulations?, Madeline Roubik

Mary Ann Bolton Undergraduate Research Award

When investigating the trafficking of wild species, animals are often considered before plants (Phelps et al. 2015). This is especially detrimental to members of the orchidaceae family, which are victims of an extensive illegal trade. It spans the entire globe but is especially concentrated in Southeastern Asia (Phelps et al. 2015). When regarding legislation, however, orchidaceae species are some of the most protected in the world. International legislation such as CITES restricts the movement of endangered orchidaceae across borders (Hinsley 2018). The 1992 Convention on Biodiversity (Lawson et al. 2019) also has policies regarding international orchid trade. National laws regulate …

Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling

All Graduate Reports and Creative Projects, Fall 2023 to Present

The rapid urbanization occurring in arid environments like the Intermountain West region of the U.S. significantly alters soil conditions. Construction of roads, buildings, and other infrastructure leads to the disturbance of soil structure, nutrient depletion, and reduced fertility. This research addresses the need for sustainable soil management practices that may restore soil health post-construction. In this study, the effectiveness of various soil amendments and application methods on specific soil parameters and turfgrass establishment in construction-disturbed soils was evaluated. The study highlights the critical role of soil amendments, particularly municipal solid waste (MSW) compost, in improving soil quality and plant growth. …

Vegetation Management During Establishment Of Native Grasses And Forb Plantings On Roadsides And Prairie Restoration, Rachel Woody-Pumford

Graduate Theses and Dissertations

North American prairies have been shrinking due to agricultural production, overgrazing, development of cities and towns, and climate change. However, integrated roadside vegetation management (IRVM) creates the opportunity to reestablish prairies along roadsides through planting native grasses and forbs. Utilizing postememergence (POST) herbicides registered for use along rights-of-way has the potential to remove invasive species and create space for newly establishing native grass and forb species. The use of clopyralid, florpyrauxifen-benzyl, metsulfuron, and quinclorac were found to be safe for use in plantings containing big bluestem (Andropogon gerardii Vitman) and butterfly milkweed (Asclepias tuberosa L.). However, florpyrauxifen-benzyl injured and stunted …

Clonal Growth And Trait Variation In The Colorado Front Range: The Influence Of Elevation And Ecosystem, Jordan Conley

Master's Theses

Amid global climate change, exploring adaptive strategies among alpine flora, particularly through clonal growth, becomes critical for biodiversity conservation. This study aims to explore the patterns of dominance and distributions among clonal species across environmental gradients in the Colorado Front Range, employing a trait-based comparative analysis to understand the adaptive strategies of alpine flora and their implications for conservation amid rapid climate change. We focused on two species, studying traits like lateral spread, bud count, and bulbil numbers. Advanced statistical methods such as Permutational Multivariate Analysis of Variance (PerMANOVA) and Multi-Response Permutation Procedures (MRPP) were used to evaluate community compositions …

Evaluation Of Essential Oils And Their Major Components For Disease Resistance, Serkan Tokgöz

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Essential oils (EOs) are natural hydrophobic compounds, which are highly complex, typically comprising 20 to 60 constituents, with two or three main components making up 20% to 95% of their composition, alongside other minor constituents. Research has firmly established the potent antibacterial and antifungal properties of EOs and their primary components. To assess their efficacy, one EO, nutmeg oil, and seven main components, including safrole, toscanol, safraleine, cinnamaldehyde, carvacrol, carvone, and thymol, were tested against four economically significant fungal pathogens (Alternaria solani, Fusarium graminearum, Rhizoctonia solani, and Sclerotiorum sclerotiorum), one oomycete pathogen (Phytium ultimum …

Malt Quality Parameters For Malting Barley, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Have you ever wondered how beer is made and what makes barley varieties different from each other in the eyes of the brewer? The barley malting process and main barley malt quality characteristics are briefly described on this page.

Effective Furrow Sowing For Water Repellent Soils, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Furrow sowing creates micro-relief, small ridges, and furrows into which water can be harvested. Sloping water repellent surfaces induce run-off, which collects at the base of the sown furrow, enhancing water entry through increased hydraulic pressure.

Salinity Tolerance Of Flowering Rush, Butomus Umbellatus, Andrew Coomes

Master's Theses

Flowering rush is an invasive aquatic plant in North America that causes deleterious effects to native ecosystems. There are two cytotypes, a triploid and diploid, and multiple genotypes contained within the diploid cytotype currently established in the U.S. Despite its presence in river drainages connected to estuarine areas, documentation on the salinity tolerance of flowering rush is scarce. Currently, information is limited to anecdotal reports suggesting intolerance to saline conditions. A better understanding of the osmotic tolerance of this species is essential to providing insight into its’ invasive range and better inform management efforts. These studies investigated vegetative propagule germination …

Ability Of Genomic Prediction To Bi-Parent-Derived Breeding Population Using Public Data For Soybean Oil And Protein Content, Chenhui Li, Qing Yang, Bingqiang Liu, Xiaolei Shi, Zhi Liu, Chunyan Yang, Tao Wang, Fuming Xiao, Mengchen Zhang, Ainong Shi, Long Yan

Horticulture Faculty Publications and Presentations

Genomic selection (GS) is a marker-based selection method used to improve the genetic gain of quantitative traits in plant breeding. A large number of breeding datasets are available in the soybean database, and the application of these public datasets in GS will improve breeding efficiency and reduce time and cost. However, the most important problem to be solved is how to improve the ability of across-population prediction. The objectives of this study were to perform genomic prediction (GP) and estimate the prediction ability (PA) for seed oil and protein contents in soybean using available public datasets to predict breeding populations …

Relationships, Species Boundaries, And Speciation Of Piper Section Enckea, Cara Jean Hastings

Boise State University Theses and Dissertations

Species are fundamental biological units but defining what constitutes a species has been debated by biologists, philosophers, and other scholars. Our concept of what constitutes a species has evolved over time, reflecting progress and advances in technology and types of data available as well as increased understanding of the complexity of the speciation process. To understand how extant species evolved, it is useful to evaluate their relationships using molecular data in a phylogenetic framework. By pairing phylogenetic data with other types of data including morphological and fossil data as well as topographical and climatic history, we can gain understanding of …

Genetic Dissection Of Diverse Seed Coat Patterns In Cowpea Through A Comprehensive Gwas Approach, Haizheng Xiong, Yilin Chen, Waltram Ravelombola, Beiquan Mou, Xiaolun Sun, Qingyang Zhang, Yiting Xiao, Yang Tian, Qun Luo, Ibtisam Alatawi, Kenani Edward Chiwina, Hanan Mohammedsaeed Alkabkabi, Ainong Shi

Poultry Science Faculty Publications and Presentations

This study investigates the genetic determinants of seed coat color and pattern variations in cowpea (Vigna unguiculata), employing a genome-wide association approach. Analyzing a mapping panel of 296 cowpea varieties with 110,000 single nucleotide polymorphisms (SNPs), we focused on eight unique coat patterns: (1) Red and (2) Cream seed; (3) White and (4) Brown/Tan seed coat; (5) Pink, (6) Black, (7) Browneye and (8) Red/Brown Holstein. Across six GWAS models (GLM, SRM, MLM, MLMM, FarmCPU from GAPIT3, and TASSEL5), 13 significant SNP markers were identified and led to the discovery of 23 candidate genes. Among these, four specific …

Turfgrass Soil Surfactants: Examining Active Ingredients, Application Strategies, And The Structure–Function Relationship In Sand-Based Putting Greens, Daniel O'Brien

Graduate Theses and Dissertations

Soil surfactants, commonly referred to as wetting agents, are a leading water management strategy for golf courses. Non-ionic block copolymers are the most common type of turfgrass soil surfactant. However, differences in the registration process and labeling requirements allow soil surfactants to enter the marketplace accompanied by far-less data compared to other products used on golf courses. This has led to considerable confusion among golf course superintendents. Three primary sources of confusion are: (i) the widely-used marketing terminology of “penetrants” and “retainers” to classify wetting agents; (ii) active ingredients which in some cases are not disclosed at all; and (iii) …

Identifying Grassland Cores In The Southeast: Relating Spatial Covariance To Avian Communities And Vegetation Structure, Lauren L. Berry

Graduate Theses and Dissertations

Globally, grasslands are declining in range, which is leading to a decline in grassland-dependent taxa. These declines can be attributed to a variety of issues, a major one being the encroachment of woody species into historic grasslands. There is a new framework for strategizing grassland management, referred to as “Defend the Core,” which calls for proactive management of intact grasslands, meaning conserving remaining grasslands by preventing woody encroachment in the first place. To successfully defend the core, it is imperative that we develop rapid methods to identify intact grassland cores for management priority. One method that can be used for …

Genome-Wide Association Study/ Genomic Prediction Of Cowpea Seed Protein And Black Seed Coat Color In Cowpea, Yilin Chen

Graduate Theses and Dissertations

Cowpea (Vigna unguiculata [L.] Walp) is a crucial crop in many regions, serving as a vital protein source for humans and livestock. Addressing the need to enhance its nutritional quality and make it easier to cultivate cowpeas of specific colors, this study utilized genome-wide association studies (GWAS) to identify markers associated with protein content and seed coat color patterns in cowpea.

In the protein content study, a GWAS was conducted on 161 cowpea accessions using 110,155 high-quality single-nucleotide polymorphisms (SNPs). Seven significant SNP markers were identified, all located at a locus on chromosome 8 associated with the gene Vigun08g039200, enhancing …

Combining Temperature-Dependent Life Table Data Into Insect Life Cycle Model To Forecast Fall Armyworm Spodoptera Frugiperda (Je Smith) Distribution In Maize Agro-Ecological Zones In Africa, Marian Adan, Henri E.Z. Tonnang, Cojdo E.F. Kassa, Klaus Greve, Christian Borgemeister, Georg Goergen

All Peer-Reviewed Publications

The fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an invasive agricultural pest, has significantly impacted crop yields across Africa. This study investigated the relationship between temperature and FAW life history traits, employing life cycle modeling at temperatures of 20, 25, 28, 30, and 32̊C. The development time for eggs, larvae, and pupae varied from 0–3 days, 10–18 days, and 7–16 days, respectively. The optimal temperature range for immature stage survival and female fecundity was identified as 21–25̊C, with the intrinsic rate of increase (rm) and gross reproductive rate (GRR) peaking at 25–28̊C. Model validation confirmed the accuracy of …

Plastid Translation As A Developmental Checkpoint? Plastid Ribosomal Protein Emb27 Is Required For Maize Embroyogenesis, Janlo M. Robil

Biology Faculty Publications

No abstract provided.

Mapping Quaking Aspen Using Seasonal Sentinel-1 And Sentinel-2 Composite Imagery Across The Southern Rockies, Usa, Maxwell Cook, Teresa Chapman, Sarah Hart, Asha Paudel, Jennifer Balch

Aspen Bibliography

Quaking aspen is an important deciduous tree species across interior western U.S. forests. Existing maps of aspen distribution are based on Landsat imagery and often miss small stands ( < 0.09 ha or 30 m²), which rapidly regrow when managed or following disturbance. In this study, we present methods for deriving a new regional map of aspen forests using one year of Sentinel-1 (S1) and Sentinel-2 (S2) imagery in Google Earth Engine. Using observed annual phenology of aspen across the Southern Rockies and leveraging the frequent temporal resolution of S1 and S2, ecologically relevant seasonal imagery composites were developed. We derived spectral indices and …

Green And Blue Water Footprints Of Major Crops In The Wami/Ruvu Basin, Tanzania: Implications For Water Scarcity And Sustainability, Benson Hm Lazaro, Martine M. Hagai, Rubhera Ram Mato

Tanzania Journal of Science

Accurate estimation of the blue and green water requirements of the various crops cultivated in a water basin is essential for planning specific plant/crop irrigation schedules. In this study, the crop water requirements of the major crops grown in the Wami/Ruvu basin were determined using the FAO-CROPWAT model based on meteorological parameters: monthly maximum and minimum temperature, wind speed, mean relative humidity, sunshine hours, rainfall data, and effective rainfall for 23 hydro-meteorological stations distributed in the study area. The studied crops are rice, maize, beans, tomatoes, and sugarcane. The crop reference evapotranspiration (ETo) and actual evapotranspiration (ETc) for each crop …

Microbiological Quality Of Irrigation Water And Leafy Vegetables In Dar Es Salaam, Tanzania, Bubelwa L. Kamara, Godwill D. Mrema, Thomas J. Lyimo

Tanzania Journal of Science

The quality of water used for the irrigation of leafy vegetables in urban settings is in doubt due to contamination associated with poor hygiene and water pollution. This study examined the microbiological quality of irrigation water and leafy vegetables at Chang’ombe in Dar es Salaam, Tanzania as well as the perceptions and level of awareness of nearby consumers. Water and leafy vegetable samples were analysed for faecal coliform (FC) using standard techniques. Perception and awareness of consumers were collected using a questionnaire survey. The results showed an average FC count of 406.1 ± 16.40 MPN/100 ml for the irrigation water. …

Extraction Of Natural Dyes From Delonix Regia Flowers For Cotton Fibres, Lutamyo Nambela, Liberato V Haule

Tanzania Journal of Science

Textile colouration is among the major industry that pollutes the environment with effluents rich in dye chemicals. Most of the dyes used are synthetics which possess health and environmental impacts. Potentially, the use of bio-based dyes and other chemicals can lessen the environmental challenges of the textile effluents. This study reports on sustainable extraction and dyeing of cotton fabric using extract of Delonix regia flowers. The extraction process was done using acidified water as a solvent and the dyeing process was free from hazardous auxiliary chemicals. To improve the dyeing performance, banana sap was used as an affordable and eco-friendly …

Genetic Characterization Of Water Yam (Dioscorea Alata L.) And Production Constraints Of Yam In Pwani Region And Unguja Island, Tanzania, Gladness E Temu, Veneranda E Mlegi, Nessie D Luambano

Tanzania Journal of Science

Yam (Dioscorea spp.) is a tuber crop cultivated in over 30% of all regions in Tanzania, contributing to the carbohydrate needs of many households. The morphological and genetic diversity of water yam (D. alata L.) local cultivars collected from Pwani region and Unguja Island were evaluated using 26 agro-morphological characters and 10 Short Sequence Repeat (SSR) markers. Cluster analysis using morphological characters classified nine water yam local cultivars into two main clusters with three subclusters. Tuber flesh and leaf colour were the main descriptors for clustering. The genetic diversity of 128 water yam genotypes using ten polymorphic SSR markers generated …

Modeling The Transmission Dynamics Of Tuberculosis In Humans, Farida Kisinda, Joshua A. Mwasunda, Mbwiga S. Aloni

Tanzania Journal of Science

Tuberculosis (TB) is a major threat to human health particularly in most of developing countries. In this article, we formulate and analyze a deterministic model for the transmission dynamics of pulmonary and extra-pulmonary tuberculosis. The next generation method is employed to find the basic reproduction number which helps to determine whether TB clears or persists in the human population. Global stability of model equilibria is done through Lyapunov functions whereas the normalized forward sensitivity index method is adopted to determine parameters that drive tuberculosis. Analysis shows that both TB free and endemic equilibria exist. The TB free equilibrium is globally …

Ecosystem Response To Increasing Hurricane Disturbance: Comparing Nutrient Cycling Dynamics Associated With Early- And Late-Successional Tree Species In A Wet Tropical Forest, Miriam Kleit

Biology Honors Projects

Puerto Rico has seen changes in the frequency and severity of disturbances in recent years as hurricanes become more frequent and more intense under climate change. In ecosystems experiencing increasing disturbances, we expect that species composition will shift as early successional trees become more common. These changes to species composition and community ecology are likely to affect terrestrial nutrient cycling both directly and indirectly, and it is still not well understood how shifting community composition may alter ecosystem functioning. To address this gap, I measured carbon (C) and nitrogen (N) variables in soils, microbial biomass, roots, leaves, and soil greenhouse …