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Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample
Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample
Theses and Dissertations
Increasing wetland restoration in the Lower Mississippi Alluvial Valley has been identified as a method to reduce nutrient loading in the Gulf of Mexico. Wetlands have historically been used to treat water through processes facilitated by wetland plants, and relatively few species and plant traits have been identified as important in carrying out these processes. This study focuses on some of those species and traits and aims to identify species differences and plant traits that may be important for wetland nutrient mitigation. Chapter I provides background information on nutrient pollution, wetland biogeochemical mechanisms for nutrient sequestration, and the focal species …
Interactive Effects Of Bark Beetles, Ophiostomatoid Fungi, And Subterranean Termites On Wood Decomposition And The Biogeochemical Cycling Of Pine Forests, Kimberlyn Pace
Theses and Dissertations
A frequent source of pine tree mortality in recent years can be attributed to pine bark beetles and their vectored Ophiostomatoid fungi, an organism that has been observed to attract subterranean termites that preferentially recruit to this downed woody debris. This interaction may significantly modify biogeochemical fluxes in bark beetle mass mortality events, but studies are often limited to singular regions or single pine-dominated ecosystems. Two studies were designed to test the interactive effects of these associations on terrestrial biogeochemical cycles and decomposition processes, the first using replicated field trials in Mississippi, Arizona, and Honduras across two years and the …
Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby
Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby
Theses and Dissertations
12 N treatments in 2020 and 11 in 2021 were replicated four times over four locations in a randomized complete block design. The first research tested the efficacy of CYG for Mississippi corn (Zea mays L.) production. The optimum N rates were calculated by fitting four models. Differences between the CYG rate and AONR were compared. AONR varied from 134 to 301 kg N ha–1 at different management levels. When we compared the AONR to the CYG rate, the CYG rate over-recommended N in 12 of the 14 possible comparisons. The second study compared different VIs, methods, and sensors at …
An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew
Theses and Dissertations
Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …
Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker
Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker
Theses and Dissertations
Nitrogen run-off from agriculture have been linked to human health problems on a global level. Large-scale conventional producers struggle to redefine themselves as sustainable because reducing nitrogen (N) inputs without justification or validation may lead to severe profit losses. Small unmanned aerial systems (sUAS) sensing may allow for decreased N runoff. Failure to address this problem will exacerbate already excessive N runoff into the Mississippi River and beyond. The purpose of this study was to reduce fertilizer N input using sUAS technology to assess crop canopy needs. In 2020 and 2021, variable rate nitrogen (VRN) side-dress N application maps were …
Determining The Effectfs Of Introducing Pseudomonas Putida 3p To Black Soldier Fly (Hermetia Illucens) Gainesville Diet, Rebecca Waters
Determining The Effectfs Of Introducing Pseudomonas Putida 3p To Black Soldier Fly (Hermetia Illucens) Gainesville Diet, Rebecca Waters
Theses and Dissertations
With a growing global population, food security and waste management strategies are needed (FAO, 2002b); insects have been promoted for these goals. Black soldier fly larvae (BSFL) are endorsed for their ability in decomposition and use as feed (Bava et al., 2019; Swett Walker, 2018). Studies show the life cycle of BSFL is impacted by bacterial supplementation (Franks et al., 2021; Kooienga et al., 2020). We seek to determine the effects of supplementing BSFL diet with Pseudomonas putida 3P. We conducted two forms of a 10-day bench-top study observing larval mass, frass conversion, C:N content, and ammonia production with supplementation …
Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne
Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne
Theses and Dissertations
Corn is one of American agriculture's greatest success stories, where we have witnessed incredible increases in yield potential over the last half-century. However, abiotic stress is still the primary limiting factor preventing plants from reaching their true yield potential. In addition, agriculture is not exempt from the deleterious effects of changing weather patterns and the altered climate our world will face as time progresses. Thus, increasing our understanding of how crops interact with their environment both above and below the soil will be crucial to increasing production on a global scale while maximizing profitability at a local level. Five studies …
Multispectral In-Field Sensors Observations To Estimate Corn Leaf Nitrogen Concentration And Grain Yield Using Machine Learning, Razieh Barzin
Multispectral In-Field Sensors Observations To Estimate Corn Leaf Nitrogen Concentration And Grain Yield Using Machine Learning, Razieh Barzin
Theses and Dissertations
Nitrogen (N) is the most critical fertilizer applied nutrient for supporting plant growth. It is a critical part of photosynthesis as a component of chlorophyl, hence it is a key indicator of plant health. In recent years, rapid development of multispectral sensing technology and machine learning (ML) methods make it possible to estimate leaf chemical components such as N for predicting yield spatially and temporally. The objectives of this study were to compare the relationships between canopy reflectance and corn (Zea mays L.) leaf N concentration acquired by two multispectral sensors: red-edge multispectral camera mounted on the Unmanned Aerial Vehicle …
Evaluation Of Narrow Corn (Zea Mays L.) Production And Management In Mississippi And Management Of Glufosinate Herbicide Applications On Palmer Amaranth (Amaranthus Palmeri) Control In Cotton (Gossypium Hirsutum), John Joseph Williams
Theses and Dissertations
Narrow row corn production has gained interest in the Mid-South region over the last several years. This narrow row spacing interest has been inspired by increase of soybean grain yield from narrow rows. Therefore, production practices were evaluated for proper management of narrow row corn production. Additionally, the management of glyphosate- and potentially auxin-resistant weeds place pressure on other POST chemistries. Therefore, optimizing glufosinate applications are essential for control of Palmer amaranth. The objectives of this research were four-fold: 1) evaluate the phenotypic and grain yield responses of narrow row corn production under irrigated conditions, 2) test corn hybrids for …
Agronomic And Physiological Responses Of Resistant And Susceptible Cotton Genotypes To Reniform Nematode Severity And Soil Nitrogen, Bhupinder Singh
Agronomic And Physiological Responses Of Resistant And Susceptible Cotton Genotypes To Reniform Nematode Severity And Soil Nitrogen, Bhupinder Singh
Theses and Dissertations
Rotylenchulus reniformis (RN) nematode infection has been identified as a major biotic factor limiting cotton yield (~8%) in Mississippi. Cotton researchers are striving to develop resistance to RN and develop management practices to mitigate the problem. Reniform nematode and soil nitrogen (N) directly affect cotton growth and physiology, however, responses to RN and N may vary across a wide genetic background. The overall objective of this research was to determine the role that host plant resistance to reniform nematode and soil nitrogen plays in cotton growth, physiology, and yield and controlling RN populations. In experiment 1, the effect of RN …
Multi-Platform Comparison Of Canopy Reflectance On Corn Whole Plant And Leaf Tissue Nitrogen Status, Zachary Thomas Sumner
Multi-Platform Comparison Of Canopy Reflectance On Corn Whole Plant And Leaf Tissue Nitrogen Status, Zachary Thomas Sumner
Theses and Dissertations
Single-rate blanket application of fertilizer nitrogen (N) can result in an over or under application. Variable rate (VR) applications tailored to actual crop demands can improve N use efficiency in spatially variable soils. The objective of this study was to compare and improve relationships derived between corn canopy reflectance and corn N status acquired with two sensing platforms. Four fertilizer N rates were used, from deficient to excess, to create varying corn N status. Sensing and biophysical sampling was taken throughout the season for analysis and comparison to calculated vegetation indices (VIs). Results show strong relationships between VIs and corn …
Rice (Oryza Sativa) Response And Management Following Exposure To Sub-Lethal Rates Of Non-Target Herbicides, Benjamin Lawrence
Rice (Oryza Sativa) Response And Management Following Exposure To Sub-Lethal Rates Of Non-Target Herbicides, Benjamin Lawrence
Theses and Dissertations
Research was conducted at the Mississippi State University Delta Research and Extension Center from 2015 to 2018 to (1) determine the effects of sub-lethal concentrations of paraquat, metribuzin, fomesafen, and cloransulam-methyl applied at different rice growth stages, determine the effects on rice growth of simulated off-target paraquat applications at varying concentration based on a proportionally decreased carrier volume characterize rice response to a sub-lethal concentration of paraquat in combination with common POST and residual herbicides, assess whether starter N fertilizer or different N fertilizer management strategies can aide in rice recover after exposure to a sub-lethal concentration of paraquat, and …
(Meso-Tetra(N-Methyl-4-Pyridyl)Porphyrin)Manganese(Iii) Iodide: A Water Stable Catalyst For The Aziridination Of Olefins, Daniel Karl Wolgemuth
(Meso-Tetra(N-Methyl-4-Pyridyl)Porphyrin)Manganese(Iii) Iodide: A Water Stable Catalyst For The Aziridination Of Olefins, Daniel Karl Wolgemuth
Theses and Dissertations
Aziridines are important building blocks for the synthesis of a wide range of organic compounds, including biologically active compounds and pharmaceuticals. The development of more cost-effective catalysts for atom transfer reactions is a continuing area of research in chemistry. Transition metal complexes have been shown to catalyze the aziridination of olefins, however, most require expensive metal ions or complex ligands. Meso-tetra(N-methyl-4-pyridyl)porphyrin (TMPyP4) is a highly charged, planar ligand that has been used to support manganese(III) in complexes like Mn[TMPyP4]I5. Herein we report the optimization of the reaction conditions for the aziridination of olefins in water and buffered solutions catalyzed by …
Could Mesophyte Canopy, Bark, And Leaf Litter Traits Drive Future Flammability Of Upland Oak Forests?, Emily Kathleen Babl
Could Mesophyte Canopy, Bark, And Leaf Litter Traits Drive Future Flammability Of Upland Oak Forests?, Emily Kathleen Babl
Theses and Dissertations
In the absence of canopy-opening disturbances, upland oak forests in the eastern United States are shifting to shade-tolerant, fire-sensitive tree species (i.e. mesophytes) via a hypothesized positive feedback loop of less flammable, self-promoting conditions, termed mesophication. To evaluate species-specific impacts on mesophication, I quantified canopy, bark, and leaf litter traits of five hypothesized mesophytes [red maple (Acer rubrum), sugar maple (A. saccharum), American beech (Fagus grandifolia), hickory (Carya spp.), and tulip poplar (Liriodendron tulipifera)] and four upland oaks [black oak (Quercus velutina), chestnut oak (Q. montana), scarlet oak (Q. coccinea), and white oak (Q. alba)] in central Kentucky. Red maple, …
Alternative Post Emergence Nitrogen Management Strategies For Delayed-Flood Rice Production, Richard Edward Turner
Alternative Post Emergence Nitrogen Management Strategies For Delayed-Flood Rice Production, Richard Edward Turner
Theses and Dissertations
Rice (Oryza sativa L.) that is grown in the U.S. is predominantly grown in the mid-south. Current Mississippi State University recommendations for nitrogen (N) fertilization of rice suggest a single application of 168 kg N ha-1 on soils with CEC ¡Ü 20 and 202 kg N ha-1 on soils with CEC > 20. The primary objective was to identify alternative N management strategies that may potentially be used to reduce costs associated with aerial application of N fertilizer to rice. Research was established at the Delta Research and Extension Center, at Stoneville, MS, on two soil textures during 2015 and 2016. …
Stabilized Urea Fertilizer Effects On Corn Nitrogen Use Efficiency And Soil Nitrogen Transformations, Michael Paul Nattrass
Stabilized Urea Fertilizer Effects On Corn Nitrogen Use Efficiency And Soil Nitrogen Transformations, Michael Paul Nattrass
Theses and Dissertations
Urea based fertilizers are susceptible to N losses through volatilization, denitrification, and leaching. A field and incubation experiment were conducted at Mississippi State between 2013 and 2015 to evaluate the effect of fertilizer stabilizers on grain yield, N use, and N transformations in various soil textures. Stabilizers were applied to liquid urea-ammonium-nitrate (UAN) solution (32%) and granular urea (46-0-0) at labeled rates for 179 and 112 kg N ha-1 for the field and incubation experiments, respectively. Grain yield and N content at tasseling and physiological maturity were measured for the field experiment. Extracts from the incubation experiment were measured for …
Strategies For Establishment And Low Input Forage Production Of Southeastern Wildrye, Matthew Thomas Thornton
Strategies For Establishment And Low Input Forage Production Of Southeastern Wildrye, Matthew Thomas Thornton
Theses and Dissertations
Southeastern wildrye (Elymus glabriflorus (Vasey ex L.H. Dewey) Scrib & C.R. Ball) is a relatively new perennial cool-season grass that has shown potential as a forage crop in the Southeastern United States. However, there is a lack of research on this species assessing its agronomic performance. To assess the agronomic performance and it’s tolerance to imazapic field trials were established in Newton and Starkville, MS. A forage production trial included five nitrogen (N) 0, 56, 112, 168, and 224 kg N ha -1 (high input) and five annual clover (low input) treatments. Tolerance to imazapic was assessed with applications of …
Utilization Of Canopy Reflectance To Predict Yield Response Of Corn And Cotton To Varying Nitrogen Rates, Totsanat Rattanakaew
Utilization Of Canopy Reflectance To Predict Yield Response Of Corn And Cotton To Varying Nitrogen Rates, Totsanat Rattanakaew
Theses and Dissertations
Fertilizer N is one of the most costly inputs in corn (Zea mays L.) and cotton (Gossypium hirsutum L.) production and is a strong yield determining factor. Variable rate N fertilization has the potential to improve resource use efficiency, profitability, and help to minimize adverse environmental impacts. Vegetation indices (VIs) may be useful for in-season crop health monitoring to assist in fertilizer N management and yield prediction. This research determined the utility of aerial imagery in detecting corn and cotton response to varying N supply using five selected VIs. The VIs derived from aerial images, chlorophyll readings and tissue N …
Evaluating The Relationship Between Cotton (Gossypium Hirsutum L.) Crop Management Factors And Tarnished Plant Bug (Lygus Lineolaris) Populations, Chase Allen Samples
Evaluating The Relationship Between Cotton (Gossypium Hirsutum L.) Crop Management Factors And Tarnished Plant Bug (Lygus Lineolaris) Populations, Chase Allen Samples
Theses and Dissertations
Tarnished plant bug is the most important insect pest of cotton in Mississippi. Management of this insect is difficult because of insecticide resistance as well and the overwhelming population densities in many areas of the Mississippi Delta. Given the level of plant bug infestation and damage observed in cotton over the past several growing seasons, information is needed to improve management of vegetative growth once fruit retention is reduced. Little data exists regarding the impact of nitrogen application on infestation by tarnished plant bug. In addition, growers have been progressively reducing seeding rates as seed and technology fees have increased …
Genotype, Nitrogen And Harvest Management Effects On Switchgrass Production, Ramdeo Seepaul
Genotype, Nitrogen And Harvest Management Effects On Switchgrass Production, Ramdeo Seepaul
Theses and Dissertations
Use of switchgrass (Panicum virgatum L.) as a forage and feedstock species requires knowledge of fertilizer application rates and harvest timing to optimize yield and quality. Three experiments were conducted at the Brown Loam Branch Experiment Station, Raymond, MS to quantify nitrogen rates, harvest timing, and genotype effects on biomass, nutrient removal, chemical composition and ethanol yield. Dry matter yield varied with N rate, genotype, harvest frequency and timing. Yields among genotypes were: NF/GA992 = NF/GA001 (13.7 Mg ha-1) > Alamo (11.6 Mg ha-1) > Cave-in-Rock (6.1 Mg ha-1). A single (9.5 Mg ha-1) or two harvests annually (10.3 Mg ha-1) produced …
Evaluation Of Sediment And Nutrient Loss During The Revegetation Of Mississippi Roadsides, Kyle R. Briscoe
Evaluation Of Sediment And Nutrient Loss During The Revegetation Of Mississippi Roadsides, Kyle R. Briscoe
Theses and Dissertations
Runoff during the revegetation of roadsides can transport sediment and nutrients offsite, leading to surface water quality reductions. Two field experiments were conducted near Starkville, MS in 2011 and 2012 to evaluate the influence of N and P sources and rates, fertilization timing, and mulch type on vegetative establishment and nutrient and sediment runoff losses. Stainless steel runoff frames (0.75 x 2.0 m) were installed on 10% and 15% slopes for Experiment I and Experiment II, respectively. A bahiagrass (Paspalum notatum Flugge), tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.], sericea lespedeza [Lespedeza cuneata (Dum. Cours.) G. Don], and common …
Development Of Mathematical Model For Abiotic Stresses And Cotton Fiber Quality, Suresh Bajirao Lokhande
Development Of Mathematical Model For Abiotic Stresses And Cotton Fiber Quality, Suresh Bajirao Lokhande
Theses and Dissertations
Abiotic stresses cause extensive losses to agriculture production worldwide. Cotton (Gossypium hirsutum L.) is an important fiber crop grown widely in subtropical region where temperature, water and nutrients are the common factors limiting crop production. Such losses could be more severe in the future climate as intensity and frequency of those stresses are projected to increase. The overall goal of this study was to evaluate effects of abiotic stresses on cotton reproductive performance and develop functional algorithms for fiber properties in response to different stress factors. Three experiments were conducted to evaluate the effects of temperature, water, and nitrogen in …
The Effect Of Variable Organic Matter On Site Productivity, Soil Nutrients, And Carbon On A Southern Loblolly Pine Plantation, Jason Craig Mack
The Effect Of Variable Organic Matter On Site Productivity, Soil Nutrients, And Carbon On A Southern Loblolly Pine Plantation, Jason Craig Mack
Theses and Dissertations
This study examined the effect of manipulating forest floor and harvest residue inputs on nutrient availability and carbon content in the context of intensive forest management. Treatments were removal and addition of forest floor and slash, and a reference. Tree volume, litterfall, and root biomass were measured to assess aboveground productivity and soil moisture and temperature, available nitrogen and phosphorus, O-horizon, and mineral soil for below ground processes. Organic matter additions increased stand bole volume, carbon at 20-60cm, and total nitrogen in the mineral soil. Severely removing the floor and harvest residues did not result in any large differences in …
Study Of Food Digestion And Morphology Of Subterranean Termites From Mississippi, Timothy Joseph Arquette
Study Of Food Digestion And Morphology Of Subterranean Termites From Mississippi, Timothy Joseph Arquette
Theses and Dissertations
The overall aim of this study was to provide new and updated information about subterranean termite morphology and digestive physiology. Scanning electron microscopy was used to obtain high resolution images of morphological features of the termite cuticle not discernable by light microscopy. In addition, digital scanning electron micrographs clearly show the appearance of wood particles recovered from the termite digestive tract at different stages of digestion. The ability of termites to obtain and conserve nitrogen in their diet was demonstrated by establishing whether the insect can digest chitin, as well as from determination of levels of soluble proteins and uric …
Effectiveness Of Crop Reflectance Sensors On Detection Of Cotton (Gossypium Hirsutum L.) Growth And Nitrogen Status, Tyson Brant Raper
Effectiveness Of Crop Reflectance Sensors On Detection Of Cotton (Gossypium Hirsutum L.) Growth And Nitrogen Status, Tyson Brant Raper
Theses and Dissertations
Cotton (Gossypium hirsutum L.) reflectance has potential to drive variable rate N (VRN) applications, but more precise definitions of relationships between sensor-observed reflectance, plant height, and N status are necessary. The objectives of this study were to define effectiveness and relationships between three commercially available sensors, and examine relationships of wavelengths and indices obtained by a spectrometer to plant height and N status. Field trials were conducted during 2008-2010 growing seasons at Mississippi State, MS. Fertilizer N rates ranged from 0-135 kg N ha-1 to establish growth differences. Sensor effects were significant, but sensors monitoring Normalized Difference Vegetation Index (NDVI) …
Nitrogen Doping In Low Temperature Halo-Carbon Homoepitaxial Growth Of 4h-Silicon Carbide, Kritsa Chindanon
Nitrogen Doping In Low Temperature Halo-Carbon Homoepitaxial Growth Of 4h-Silicon Carbide, Kritsa Chindanon
Theses and Dissertations
With the low-temperature halo-carbon epitaxial growth technique developed at MSU prior to this work, use of a halo-carbon growth precursor enabled low-temperature homoepitaxial process for 4H-SiC at temperatures below 1300 °C with good quality. Investigations of the nitrogen doping dependence are reported. It has been demonstrated that the efficiency of the nitrogen incorporation may be different for different substrate orientations, with the Cace showing the higher value of doping. The Si/C ratio is known to influence the doping during the epitaxial growth due to the site-competition mechanism. The doping on the Cace showed weak dependence on the Si/C ratio. On …
Integrated Optical Fiber Laser Raman Sensor For Cryogenic Application, Appolinaire Tifang Luanje
Integrated Optical Fiber Laser Raman Sensor For Cryogenic Application, Appolinaire Tifang Luanje
Theses and Dissertations
An integrated fiber optical Raman sensor was designed for real-time, non –intrusive detection of liquid and gaseous mixtures at high pressure and high flow rates. The integrated sensor employs a high-power solid-state pumped Nd:YAG frequency doubled (532nm) laser (3W), a modified In Photonics Raman probe which has built-in Raman signal filter optics, and two high-resolution spectrometers and photomultiplier tubes (PMT) with selected bandpass filters to collect both N2 and O2 Raman signals. The detection unit was also integrated with Lab View software interfaced PMT modules for fast data acquisition.
Development Of A Nutrient And Dissolved Oxygen Water Quality Model For The Saint Louis Bay Watershed, Janna Marie Kieffer
Development Of A Nutrient And Dissolved Oxygen Water Quality Model For The Saint Louis Bay Watershed, Janna Marie Kieffer
Theses and Dissertations
Nutrient enrichment, which can be detrimental to the health of aquatic systems, is one of the leading causes of impairment of our Nations? waters. Development and initial calibration of a hydrologic, hydrodynamic, and water quality model of dissolved oxygen and nutrient concentration for the St. Louis Bay watershed in coastal Mississippi is documented herein. The model was developed using the USEPA BASINS 3.0 analysis system and WinHSPF, a comprehensive watershed loading and transport modeling software. The resulting model simulates significant watershed and instream physical, chemical and biological processes including rainfall runoff and associated water quality from a variety of land …