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Assessing The Evaporation Method For Soil-Water Retention Curve Development And Comparison Of Soil-Water Characteristics Across Different Tillage Practices In A Furrow-Irrigated Corn (Zea Mays L.) System, Jeferson Prass Pimentel Dec 2023

Assessing The Evaporation Method For Soil-Water Retention Curve Development And Comparison Of Soil-Water Characteristics Across Different Tillage Practices In A Furrow-Irrigated Corn (Zea Mays L.) System, Jeferson Prass Pimentel

Graduate Theses and Dissertations

The thesis comprises three studies. The first study in this thesis (Chapter I) focused on a six-year corn field experiment to assess the influence of conservation agricultural practices on soil properties and their long-term effects on water-use efficiency and yield. Non-tillage management did not significantly reduce soil bulk density compared to conventional tillage, as no differences were observed between non-tillage and tillage systems throughout the 6-year experiment. There was no difference in total water-use efficiency among soil management practices in 2018, 2019, 2020, and 2021. Even though in one year of the study, a significant 24 kg ha-1 mm-1 improvement …


Survey And Prevalence Of Palmer Amaranth Herbicide Resistance In South Carolina, Mitchell Williams Aug 2023

Survey And Prevalence Of Palmer Amaranth Herbicide Resistance In South Carolina, Mitchell Williams

All Theses

Palmer amaranth is a troublesome weed for growers to control, not only due to its aggressive growth characteristics that limit row-crop production, but because of its resistance to different herbicide modes of action. The first case of herbicide resistance in Palmer amaranth was detected in 1989 and has since grown to nine different herbicide classes throughout the United States. New herbicide modes of action have not been developed since the 1980s, so proper stewardship of the remaining modes of action is important for effective control of Palmer amaranth. Increased herbicide resistance from states bordering South Carolina have been reported; therefore, …


Effect Od Different Sources And Application Rates Of Sulfur On Corn And Soybean Production Systems In Louisiana, Diego Mayorga Valladares Jan 2023

Effect Od Different Sources And Application Rates Of Sulfur On Corn And Soybean Production Systems In Louisiana, Diego Mayorga Valladares

LSU Master's Theses

Sulfur (S) is a structural component of amino acids such as cysteine and methionine and is involved in important functions within the plant like photosynthesis, carbon and nitrogen metabolism, protein synthesis of oils, and detoxification mechanisms. Sulfur deficiency in crops has intensified around the world. Some of the reasons are improvement in controlling SO2 emissions from industries, growing usage of high analysis S-free fertilizers and augmented cropping intensity. Sulfur fertilization has become an important factor in crop production systems and fertilization guidelines for S need to be up-to-date to improve use efficiency and compensate for rising prices of fertilizers. …


Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer Jan 2023

Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer

Electronic Theses and Dissertations

Corn (Zea mays L.) is a vital commodity in South Dakota’s agricultural sector. Optimal corn production occurs when there are sufficient mineral nutrients in the soil, especially potassium (K). Applications of K fertilizer are used when soil test K (STK) levels are deficient. Therefore, producers need reliable, thoroughly tested fertilizer recommendations to make profitable decisions and maintain environmental stewardship. South Dakota K fertilizer recommendations have not been updated in nearly 20 years. Simultaneously, changes in corn genetics, management practices, and climate patterns suggest that the critical soil test value (CSTV) for STK may have shifted in that same time frame. …


Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers Dec 2022

Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers

Theses and Dissertations

A long-held practice is to mix agricultural soil with a soil amendment to improve growing conditions in crops. A common soil amendment is biosolids produced from both municipal and dairy wastewater due to the macro- and micronutrients within it. Both the agricultural and wastewater industries are participating in the Circular Economy concept (CEC). Two experiments explored using expended bioelectrochemical systems (BES) that treated either synthetic dairy wastewater (DWW) or synthetic municipal wastewater (SWW) as soil amendments to improve corn plant growth when treated with three different nutrient treatments: 100%- 50%- and 0% Hoagland Nutrient Solutions. Biochar and used terracotta clay …


Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby Dec 2022

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 …


Corn (Zea Mays L.) Production In Living Mulch Systems, Grazing Potential, And Economic Viability, Marcia Peireira Quinby Aug 2022

Corn (Zea Mays L.) Production In Living Mulch Systems, Grazing Potential, And Economic Viability, Marcia Peireira Quinby

Doctoral Dissertations

Living mulch (LM) is a practice in which forages are grown simultaneously with the main crop, serving as a living cover throughout the growing season. The LM systems were developed to alleviate concerns of soil depletion and finding ways to reduce tillage negative effects on soil productivity. In addition, when legumes are use can decrease the reliance on N fertilizer. The use of corn in LM have been previously studied due to the crop being a large commodity in the U.S.; In addition, the ability to graze the LM after corn production can increase the land use efficiency. To determine …


Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne May 2022

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 …


Corn Nitrogen Management Under Different Tillage Systems, Akshara Athelly Nov 2021

Corn Nitrogen Management Under Different Tillage Systems, Akshara Athelly

LSU Master's Theses

Adoption of no-tillage (NT) and cover crops (CC) significantly effect soil physicochemical properties and nutrient cycling that necessitates modified nutrient management to maximize crop yields. Two field experiments were conducted to evaluate N-sources Urea Ammonium Nitrate (UAN), urea, and urea+ N-stabilizer (urea+ stab) and N-split applications 100%N at V2 (S1), 25%N at V2+75%N at V6 (S2), 25%N at V2+ 50%N at V6+ 25%N at VT (S3) in a sandy loam soil and three CC wheat (Triticum aestivum), hairy vetch (Vicia villosa) , and radish (Raphanus sativus) and their combinations along with three N-rates ( …


Innovative Water Management Using Advanced Irrigation Systems And Biochar, Jonathan A. Holt May 2021

Innovative Water Management Using Advanced Irrigation Systems And Biochar, Jonathan A. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two approaches to water optimization in agriculture are to increase soil water retention and improve the efficiency of irrigation. A soil amendment that has received attention for its ability to increase soil water retention is biochar, the remaining biomass after high C materials have been pyrolyzed (burned with limited oxygen and heat). Two studies were conducted at a total of 10 site-years in Utah from 2018 to 2020 to evaluate how wood biochar influences the productivity and crop quality of irrigated alfalfa (Medicago Sativa L.), corn (Zea mays L.), and wheat (Triticum L.), along with soil water tension. One study …


Evaluation Of Corn Agronomic Management Practices Following A Rye Cover Crop, Daniel John Quinn Jan 2021

Evaluation Of Corn Agronomic Management Practices Following A Rye Cover Crop, Daniel John Quinn

Theses and Dissertations--Plant and Soil Sciences

Fall implementation of a rye (Secale cereale L.) cover crop (RCC) prior to spring corn (Zea mays L.) planting is a management practice used to improve soil conservation, water quality, and limit herbicide dependence. However, corn growth and yield following a RCC is often reduced due to early-season nitrogen (N) stress and decreased plant emergence, which can limit RCC adoption. The objective(s) of this research were to evaluate corn agronomic management practices (e.g., N and seeding rate management, in-furrow (IF) starter use) following a RCC and determine which management practices can be used to limit corn stress following …


Cover Cropping In Soybean-Corn Rotation System: Economic, Agronomic, And Soil Fertility Impact, Jose Rodolfo Mite Jun 2020

Cover Cropping In Soybean-Corn Rotation System: Economic, Agronomic, And Soil Fertility Impact, Jose Rodolfo Mite

LSU Doctoral Dissertations

Planting winter-annual cover crops prevent soil erosion, reduces water runoff, and improves soil structure and soil quality. This research was conducted from 2017 to 2019 to evaluate the nutrient turnover of different species of cover crops in soils under different row crop production systems in Northeast and Central Louisiana. In Northeast Louisiana (Site 1, 2, and 3), treatments (cover crops and no cover crop) were arranged in a strip trial with three replications. At the Ben Hur Research Station, the treatments included three planting dates (September, October, and November) with [7 kg ha-1 of phosphorus (P) and potassium (K)] …


Midseason Nitrogen Sufficiency Guidelines For Corn Production In Arkansas Based On Tissue Analysis And Remote Sensing, Caio Luiz Dos Santos May 2020

Midseason Nitrogen Sufficiency Guidelines For Corn Production In Arkansas Based On Tissue Analysis And Remote Sensing, Caio Luiz Dos Santos

Graduate Theses and Dissertations

There are a lack of tools to assess midseason nitrogen (N) status in corn (Zea mays L.) production systems and identify the need for additional N fertilization. This study was conducted to determine the ability of leaf N concentration (LN) and the Dark Green Color Index (DGCI) at the 10th collared leaf stage (V10), the 12th collared leaf stage (V12), and tasseling (VT) to predict if midseason N is required to maximize corn grain yield. From 2017 to 2019, eight field studies with 11 N treatments ranging from 0 to 258 kg N ha-1 were conducted on silt loam soils …


Characterization Of Bacterial Endophytes Isolated From Brassica Carinata And Their Potential Use To Decrease Nutrient Requirements In Crops, Alex Soupir Jan 2020

Characterization Of Bacterial Endophytes Isolated From Brassica Carinata And Their Potential Use To Decrease Nutrient Requirements In Crops, Alex Soupir

Electronic Theses and Dissertations

Bacterial endophytes have the capability to enhance plant growth by producing plant growth hormones, solubilizing phosphates, suppressing pathogenic fungi, and reducing plant stress hormones. These capabilities make them desirable limiting the amount of nutrients and pesticides that are applied to crops. Through these assays and isolations, it is possible to identify novel bacterial species. In-vitro testing had shown 9 of the 20 isolates possess the ability to produce indole-3-acetic acid (IAA) with Pantoea agglomerans BC09 producing a concentration of 30.2 ng/μl over 4 days. BC09, Bacillus subilis BC10, and Pantoea sp. BC12 were able to solubilize calcium phosphate, 7 endophytes …


Sistema De Ensilaje Como Modelo De Producción En El Municipio De San José Departamento Del Guaviare, Nelby Nerieth Urrego Ramos Jan 2020

Sistema De Ensilaje Como Modelo De Producción En El Municipio De San José Departamento Del Guaviare, Nelby Nerieth Urrego Ramos

Ingeniería Agronómica

El presente trabajo se basó en el desarrollo del proyecto productivo a través de un sistema de ensilaje como modelo de producción en el municipio de San José departamento del Guaviare, en el que se describe la metodología y resultados obtenidos del desarrollo de cada uno de los componentes trabajados en el proyecto. En cuanto al componente de ingeniería agronómica se implementó una hectárea de maíz (Zea mays) del híbrido ATL 200 en el municipio de San José, con fines de ensilaje para consumo animal principalmente ganado bovino. De tal forma, que el componente de emprendimiento se basó en la …


Proyecto Productivo De Maíz (Zea Mays) Variedad Ica V109 Como Alternativa Económica En El Municipio De La Primavera, Departamento De Vichada, Raúl Andrés Aldana Andueza Jan 2020

Proyecto Productivo De Maíz (Zea Mays) Variedad Ica V109 Como Alternativa Económica En El Municipio De La Primavera, Departamento De Vichada, Raúl Andrés Aldana Andueza

Ingeniería Agronómica

Se realizó el establecimiento de un proyecto productivo agrícola de maíz (Zea mays) variedad ICA V109 en el resguardo La Pascua, municipio de La Primavera, departamento del Vichada, en un área de 15.000 m2, teniendo en cuenta todos los requerimientos técnicos necesarios en este sistema de producción agrícola, buscando así una alternativa económica para los habitantes del resguardo. Dentro del proyecto productivo se realizó un plan de manejo técnico que incluyó un plan de fertilización basado en un análisis de suelo, se efectúo un plan de manejo integrado de plagas, enfermedades y arvenses con los controles y umbrales de acción …


Microbial Degradation Of Urea Oligomers: Potential Slow Release Nitrogen Fertilizers, Maddy Bygd Jan 2020

Microbial Degradation Of Urea Oligomers: Potential Slow Release Nitrogen Fertilizers, Maddy Bygd

Departmental Honors Projects

Urea is the most commonly used nitrogen compound in fertilizers across the world. It provides the most nitrogen at the lowest cost. However, with the size and solubility of this compound, it is easily washed out of the soil. This results in the need to continuously add fertilizer to fields, creating adverse effects on the environment due to nitrogen runoff and leading to increased expenses for farmers. Triuret, a urea oligomer, is a compound with promising potential for use as a nitrogen source, providing a slower release of nitrogen into the soil. It is hypothesized that this compound can be …


Factors Influencing The Spatial Distribution Of Southern Rust In Corn, Justin Bailey May 2019

Factors Influencing The Spatial Distribution Of Southern Rust In Corn, Justin Bailey

Graduate Theses and Dissertations

Southern rust caused by the fungus Puccinia polysora (Underwood) is the most economically important foliar disease in corn (Zea mays) (Linnaeus) (Cyperales: Poaceae)) for Arkansas. The objective of this work was to determine distribution of southern rust in corn and to determine factors that may control its distribution.

During the 2017 and 2018 season, seven corn fields in Arkansas were rated for southern rust. After disease confirmation, fields were marked with GPS sample point locations in a grid pattern across the entire field. Ratings for disease severity were taken below, at, and above the ear leaf at each point every …


Nitrogen Availability And Use Efficiency In Corn Treated With Contrasting Nitrogen Sources, Avneet Kakkar Dec 2017

Nitrogen Availability And Use Efficiency In Corn Treated With Contrasting Nitrogen Sources, Avneet Kakkar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plant-soil nitrogen cycle plays a significant role in allocation of available N to plants, and improved understanding of N cycling helps sustainably increase fertilizer use efficiency. There are various processes (nitrogen mineralization and nitrification) involved in the availability and mobility of nitrogen in the soil. The primary objective of this study was to determine the NUE under contrasting nitrogen treatments over a period of five years. Additionally, we examined the effect of different N treatments on N mineralization and nitrification in conventional and organic farming systems.

This project was funded by Agriculture and Food Research Initiative Competitive Grants Program …


Temporal Evaluation Of Corn Respiration Rates Using Pressure Sensors, Gagandeep Singh Ubhi May 2017

Temporal Evaluation Of Corn Respiration Rates Using Pressure Sensors, Gagandeep Singh Ubhi

Graduate Theses and Dissertations

High respiration rate of a grain indicates faster degradation of its dry matter. Proper grain management requires chronological and precise measurements of carbon dioxide evolved from grain respiration during the postharvest storage duration. Therefore the main goal of this research was to develop a new technique that evaluates temporal corn respiration rate using pressure sensors. It was based on measuring pressure drop associated with the grain respiration in a closed container and using it to calculate the grain respiration rates.

Dry corn (Zea Mays L.) was procured from a local farmer and stored at 4ºC. Corn rewetting technique was applied …


Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser Dec 2016

Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser

Open Access Theses

Given the dynamic nature of soil nitrogen (N), inorganic N fertilization to corn (Zea mays L.) has potential to alter N pool balance by creating an accumulation or depletion of soil N. Current corn N recommendations in the common corn-soybean rotation of Indiana strive to find the best N rate that maximizes producer profit. Increasing our understanding of soil N will inform producers if they should adjust fertilizer rates for corn to influence maintenance of organic N and Carbon. Our objective was to determine residual N effects from fertilized corn in a corn-soybean rotation by measuring (1) soil N …


Evaluation Of Tillage, Crop Rotation, And Cover Crop Impacts On Corn Nitrogen Requirements In Southeastern South Dakota, Sara Louise Berg Jan 2016

Evaluation Of Tillage, Crop Rotation, And Cover Crop Impacts On Corn Nitrogen Requirements In Southeastern South Dakota, Sara Louise Berg

Electronic Theses and Dissertations

Nitrogen (N) is a vital factor of corn (Zea mays) production. Previous work in South Dakota has shown that there is uncertainty as to whether nitrogen requirements are the same for corn raised under no-till (NT) versus conventional till (CT) production systems. The objective of this study was to evaluate whether N requirements continue to be greater under long-term NT versus CT production systems in southeastern South Dakota, while also considering effects from cover crops and crop rotation. This was a two year study conducted at the SDSU Southeast Research Farm near Beresford, SD; it was superimposed on a long-term …


Evaluation Of Flame Weeding In Southeastern South Dakota, Benjamin William Arlt Jan 2016

Evaluation Of Flame Weeding In Southeastern South Dakota, Benjamin William Arlt

Electronic Theses and Dissertations

Weed management is the main yield-limiting factor in production of organic crops. Currently, organic producers have limited resources available for in-row weed management. Flame weeding has been recognized for its potential as one part of an integrated approach at weed management in organic systems. Flame weeding uses propane fueled torches to heat plant tissue and denature proteins, thus injuring or destroying the affected tissue. When properly timed, flame weeding can effectively be used for weed control in corn and soybean fields. Corn and soybean have both shown tolerances to flame weeding and minimal yield loss with well-managed and timed flame …


Physiological Evaluation And Root Morphological Differences Associated With Novel Drought Tolerant Corn (Zea Mays L.) Hybrids, Austin Gentry Scott Dec 2015

Physiological Evaluation And Root Morphological Differences Associated With Novel Drought Tolerant Corn (Zea Mays L.) Hybrids, Austin Gentry Scott

Masters Theses

Corn hybrids designated “drought tolerant” (DT) from three commercial seed companies were evaluated in order to determine the benefit of DT technology in a mid-south environment that may receive adequate but often poorly timed rainfall. Field research was conducted in 2014 and 2015 at Milan, TN where hybrid response to stress was evaluated at two planting dates and in non-irrigated and irrigated environments and greenhouse research was conducted in Jackson, TN to evaluate early season drought to plant physiology and root structure.

In 2014 and 2015, the non-irrigated trials received enough rainfall to create a high yielding environment. Since the …


Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker Dec 2015

Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker

Theses and Dissertations

Current Central American agricultural practices are environmentally and economically unsustainable, yet the ancient Maya who lived in the same region thrived for thousands of years. Archaeologists have attempted to understand the factors enabling the prolonged success and ultimate collapse of the Maya societies. Some have proposed that the karst seasonal wetlands, called bajos, that border many Maya sites in the region were an influential factor in the Maya's ability to flourish. For the past decade, researchers have used carbon isotope analyses to identify areas of ancient maize agriculture at Maya archaeological sites. In this study, we collected soil samples from …


Increasing Expression Of Hepatitis B Surface Antigen In Maize Through Breeding, Erin Suzanne Miller Mar 2015

Increasing Expression Of Hepatitis B Surface Antigen In Maize Through Breeding, Erin Suzanne Miller

Master's Theses

The hepatitis B virus (HBV) is a common virus, with two billion people infected worldwide. It causes approximately 600,000 deaths each year, despite the availability of an effective vaccine since 1982. Maize as a platform for oral vaccination can supply a heat stable vaccine, which does not require syringes or trained personnel to administer. The Hepatitis B Surface antigen was transformed into maize and this seed was used to evaluate expression levels through the breeding process. The transgene was transferred into two elite maize inbreds by backcrossing. Highest expressing ears were selected each generation until approximately 99% commercial parent was …


Managing Swine Manure In Double-Crop Soybean, Donald Joseph Graper Jul 2014

Managing Swine Manure In Double-Crop Soybean, Donald Joseph Graper

Open Access Theses

Animal production, especially swine (Sus scrofa domesticus ) and poultry, has increased in the United States prompting the need to manage the larger volume of manure beyond land applications to supply nitrogen (N) for corn (Zea mays ) production. Applying swine manure to soybean (Glycine max ) has been shown to increase grain yield due to N supply. The goal of this research was to determine if swine manure applications to double-crop soybean following wheat can limit manure N loading to the soil by extending management options, increase soybean biomass and grain production, and increase N removal …


The Effect Of Increasing Rates Of Biochar On Corn Grown In Salinas Clay Loam, Joshua Fridlund Jun 2014

The Effect Of Increasing Rates Of Biochar On Corn Grown In Salinas Clay Loam, Joshua Fridlund

Agricultural Education and Communication

In order to sustain the ever growing global population, agriculture needs to not only increase yields but to increase yields in a way that is sustainable and is either environmentally neutral or has a positive effect on the environment. Biochar offers a solution to this challenge with numerous environmental benefits, as well as agricultural benefits (Lehman and Joseph 2009). The agricultural benefits of biochar have been well documented in tropical climates, with the benefits of biochar for other climates, such as temperate climates and Mediterranean climates, relatively unknown (Blackwell et. al. 2009). To determine the effect of biochar on agricultural …


Risk Return Of Farmer-Elevator Contracts For Soybeans And Corn In Arkansas, Marei Undine Houpert Dec 2013

Risk Return Of Farmer-Elevator Contracts For Soybeans And Corn In Arkansas, Marei Undine Houpert

Graduate Theses and Dissertations

In Arkansas the contribution of Agriculture to the states GDP is comparatively high. To help farmer's return risk the grain industry developed several marketing tools to support farmers. Literature in this research field finds different results for different locations, commodities, marketing tools and marketing years. As Agriculture in Arkansas is important for its economy this study focuses on soybeans and corn produced in the fertile north-eastern area of Arkansas that uses Memphis Tennessee as a spot market palace. The examined marketing tools are pre-harvest futures hedges and forward contracts as well as post-harvest storage strategies and minimum price contracts. All …


Colonization Of Zea Mays By The Nitrogen Fixing Bacterium Gluconacetobacter Diazotrophicus, Nikita Eskin Jun 2012

Colonization Of Zea Mays By The Nitrogen Fixing Bacterium Gluconacetobacter Diazotrophicus, Nikita Eskin

Electronic Thesis and Dissertation Repository

To achieve high yields, corn fields are supplemented with nitrogen fertilizers. Nitrogen fertilizers account for a significant portion of production costs, and are harmful to the environment. Gluconacetobacter diazotrophicus, an endophytic nitrogen-fixing bacterium supplies its natural host sugarcane with a significant amount of nitrogen. This study investigated the colonization of G. diazotrophicus in seven different corn genotypes consisting of sweet and grain corn via three different methods of inoculation: soil drench, root dip, and aseptic inoculation. Sucrose content of the corn genotypes and nitrogenase activity were also analysed. Colonization was confirmed by PCR analysis. G. diazotrophicus colonization was detected using …