Plant Sciences Commons^™

Soil Health As Influenced By The Integration Of Cover Crops And Poultry Litter In North-Central Mississippi, Nikitha Reddy Kovvuri

Theses and Dissertations

Soil health-based agricultural management practices are widely promoted to improve soil structure, infiltration and reduce erosion. This study was conducted at two locations in North-Central Mississippi to evaluate the influence of different cover crop species and poultry litter on soil health that can impact crop production, climate change, and resilience. The results indicated that the cover crops showed a little effect on some soil health indicators compared to control treatment. However, in one location, rye, and a mixture of cover crops decreased bulk density and increased available water content and organic matter. The poultry litter had a positive effect on …

Managing Iron Deficiency Chlorosis (Idc) In Soybean Through A Cropping System Approach, Katelin Savannah Waldrep

Theses and Dissertations

Iron deficiency chlorosis (IDC) is a frequent problem throughout many areas of the United States where soils are high in calcium carbonate (CaCO₃), including the Blackland Prairie regions of Mississippi. The main objectives of this study were to 1) determine the effects of seven different cropping systems on IDC visual symptomology and grain yield in rainfed soybeans grown in calcareous soils, and 2) evaluate the effects of soil water tension (SWT) on IDC. Rotating soybeans with corn produced significantly higher yields for both tolerant and susceptible soybean varieties. IDC symptomology was worse, and yields were lower in cropping …

Evaluation Of Early Maturing Cultivars, Optimal Harvest Timing, And Canopy Reflectance Of Peanut To Maximize Grade And Yield, Joseph Bryan Whittenton

Theses and Dissertations

Peanut digging timing is difficult to predict due to indeterminate growth and peanut pods maturing underground, resulting in the need to research methods that provide consistent measurements, while reducing time and effort for farmers and researchers. Experiments were conducted to evaluate the accuracy of the Maturity Index 1 and Maturity Index 2 in predicting peanut grade, the accuracy of the North Carolina 2 degree day method in predicting peanut yield, and remote sensing vegetative indices sensitivity equivalence (SEq) to peanut Maturity Index 2 and harvest grade (TSMK) for cultivars IPG-914 and Georgia-06G in Mississippi.

Maturity Index 1 and …

Identification And Quantification Of Allelochemicals Associated With Weed Suppression In Sweetpotato, Varsha Varsha

Theses and Dissertations

Mississippi ranks among the leading states in sweetpotato production in the US. However, managing weeds in sweetpotato fields presents a significant challenge, and the limited availability of herbicides labeled for use in sweetpotato makes it even more challenging. The widespread and repeated use of herbicides has led to the development of weed resistance. In addition, herbicides are incompatible with the organic production system. Finding sustainable weed management strategies to provide weed control options for organic cultivation and detain the development of herbicide-resistant weeds under conventional crop production is imperative. The natural chemicals released by the plants, also called allelochemicals, can …

Physiological And Yield Responses Of Soybean Cultivars To Heat And Drought Stresses, Sadikshya Poudel

Theses and Dissertations

Soybean (Glycine max L.) is an important legume crop often exposed to heat and drought stresses during reproductive and early-seed setting stages, resulting in lower yields and seed quality. Ten soybean cultivars were phenotyped for individual (drought or heat) and combined stress tolerance. Under drought, reduced stomatal conductance and increased canopy temperature significantly reduced seed number (46%) and weight (35%). Heat stress alone reduced seed number (19%) and weight (23%) compared to control. Moreover, a degree increase in daytime temperature above 32 °C during the reproductive stage reduced seed weight by 4% and 7% under well-watered and drought conditions, respectively. …

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 …

Evaluating The Impacts Of Waterlogging Stress On Cowpea (Vigna Unguiculata L.) Growth Traits And Physiological Performance, Omolayo Joshua Olorunwa

Theses and Dissertations

The progressive increase in the global population and the rapidly changing climate have put unprecedented pressure on crop production. Cowpea is one of the world’s most important leguminous crops, contributing to food security and environmental sustainability. However, cowpea productivity is limited due to waterlogging stress. The main objective of this study was to explore physiological and biochemical mechanisms to understand how cowpea genotypes respond to waterlogging stress. Four studies were conducted in controlled and field conditions to achieve these objectives. Study 1 characterized the waterlogging tolerance of 30 cowpea genotypes in a controlled environment using 24 morphophysiological parameters with waterlogging …

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 …

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 …

Evaluation Of Soybean [Glycine Max (L.) Merr.] Cultivar Response To Prophylactic Fungicide Application, Steven B. Stoker

Theses and Dissertations

Soybean growers in the southern United States commonly deal with disease issues that can limit yield potential. As a result, growers have adopted prophylactic fungicide application targeted at specific growth stages as a standard management practice. However, yield responses to prophylactic applications have become sporadic over time. One major change that has occurred is adoption of cultivars with improved disease tolerances. Therefore, the objective of this research was to evaluate yield response of cultivars representing multiple genetic backgrounds to fungicides applied prophylactically at the R4 soybean growth stage. Experiments were conducted in 2020 and 2021 to determine the yield impact …

Effects Of Soil Management Practices On Water Infiltration And Maize Yield To Improve Mississippi River Valley Alluvial Aquifer Sustainability, Jacob Rix

Theses and Dissertations

Surface sealing and hardpans in loam soils are problematic in the Mid-South U.S. because of intense tillage. Two experiments quantified the effects of soil management practices on infiltration and maize yield in loam soils. The first study measured the impacts of in-row subsoiling frequency × furrow irrigation frequency. In-row subsoiling significantly improved the infiltration of irrigation but not the infiltration of precipitation. In-row subsoiling with low irrigation frequency is optimal to achieve profitable maize yields while encouraging groundwater conservation. In the second study, six soil management treatments were imposed. For single-ring infiltrometer tests, infiltration rates were different between the two …

Classification Models For 2,4-D Formulations In Damaged Enlist Crops Through The Application Of Ftir Spectroscopy And Machine Learning Algorithms, Benjamin Blackburn

Theses and Dissertations

With new 2,4-Dichlorophenoxyacetic acid (2,4-D) tolerant crops, increases in off-target movement events are expected. New formulations may mitigate these events, but standard lab techniques are ineffective in identifying these 2,4-D formulations. Using Fourier-transform infrared spectroscopy and machine learning algorithms, research was conducted to classify 2,4-D formulations in treated herbicide-tolerant soybeans and cotton and observe the influence of leaf treatment status and collection timing on classification accuracy. Pooled Classification models using k-nearest neighbor classified 2,4-D formulations with over 65% accuracy in cotton and soybean. Tissue collected 14 DAT and 21 DAT for cotton and soybean respectively produced higher accuracies than the …

Phenotypic Evaluation Of Energycane (Saccharum Spp.) Genotypes In Northcentral Mississippi, Wyatt Armistead Eason

Theses and Dissertations

As fossil fuel supplies decrease and concerns of climate change increase, the search for alternative sources of fuel has pushed biomass crops to the forefront of discussion. Saccharum spontaneum readily hybridizes with commercial sugarcane and lends cold tolerance and greater yields to the hybrid progeny, called energycane. Twenty genotypes were tested against an energycane variety (Ho 02-113) as a control. Two locations were tested: the HH Leveck Animal Research Center (planted in 2019), and the Bearden Dairy Research Center (planted in 2020). The Bearden Dairy Research Center yielded significantly higher than the HH Leveck Animal Research Center regarding dry matter …

Effect Of Cover Crops, Grazing And Tillage Practices On Soil Microbial Community Composition, Function, And Soil Health In East Central Mississippi Soybean Production System., Namita Sinha

Theses and Dissertations

Integrating crop and livestock is being considered to improve soil health by carbon sequestration. A two-year study (2019-2021) at CPBES in Newton, MS was aimed to evaluate soil microbial diversity in the warm, humid regions, specifically southeastern USA. Amplicons targeting bacterial 16S rRNA genes and fungal ITS2 regions were sequenced. Taxonomic assignment and microbial diversity characterization were performed using QIIME2^®. Soil fungal diversity showed significant differences (alpha diversity, p = 0.031 in yr. 2020 and beta diversity, p = 0.037 in yr. 2021). Canonical Correspondence Analysis (CCA) and Mantel test showed significant influence on fungal diversity due to …

Cover Crops And Irrigation Impacts On Corn And Soybean Production In The Mid-Southern Usa, Dillon Aaron Russell

Theses and Dissertations

Reducing groundwater withdrawals from the Mississippi River Valley Alluvial Aquifer is imperative to sustain future irrigated cropping systems in the mid-southern USA. This research was conducted to determine the impacts of cover crops and irrigation sensor thresholds on corn (Zea mays L.) and soybean (Glycine max L.) production, water productivity, irrigation water use efficiency, and soil physical properties in the Mississippi Delta. The cover crop treatments included cereal rye (Secale cereale L.), hairy vetch (Vicia villosa R.), wheat (Triticum aestivum L.)-radish (Raphanus sativus L.)-turnip (Brassica rapa L.) mix, and no cover crop. The irrigation thresholds included -40 kPa, -90 kPa, …

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 …

Evaluation Of Alternate Wetting And Drying Irrigation Management In Rice, Richard Lee Atwill Ii

Theses and Dissertations

Water level declines in the Mississippi River Valley Alluvial Aquifer (MRVAA) are attributed largely to withdrawals for rice (Oryza sativa L.) irrigation. This study was performed to determine if alternative irrigation strategies for rice could reduce withdrawal from the MRVAA without having an adverse effect on grain yield, grain quality, control of barnyardgrass, and profitability. Research was conducted in Stoneville, MS and 19 on-farm locations across the Delta region of Mississippi from 2014 through 2017 to determine the irrigation threshold for alternate wetting and drying (AWD) rice irrigation, the effect of AWD management on barnyardgrass control, and effects of …

Quantifying The Variability In Heavy Metal Concentrations In Produce Grown In Metals-Rich Soil, Harris Lowell Byers

Theses and Dissertations

Childhood Pb exposure is associated with a multitude of poor health outcomes. In food-insecure areas, growing fresh produce in residential backyard gardens is one option for parents; however, commonly grown crops are known to accumulate Pb in consumable tissues when grown in metals-rich soils. A variety of produce representing a continuum of consumable tissues were grown in soils collected from two residential vegetable gardens, a former metal foundry, and commercial topsoil purchased from a local hardware store. The concentrations of heavy metals in crop tissues were measured with custom wavelength dispersive X-ray Fluorescence (WD-XRF) spectroscopy and portable energy dispersive X-ray …

Nutrient Loading Reduction In A Tile Drained Agricultural Watershed Through Watershed-Scale Cover Cropping: A High Resolution Analysis, Benjamin Gerald Bruening

Theses and Dissertations

Nutrient pollution originating from agricultural regions in the Midwest is a serious issue, leading to pollution of drinking water sources as well as large hypoxic zones in the Gulf of Mexico. The source of much of this contamination has been shown to be runoff from agricultural fields in the Upper Mississippi River Basin. One method that has been shown to reduce this pollution from the Upper Mississippi River Basin is the planting of winter cover crops. Winter cover crops such as rye and tillage radish have been shown to significantly reduce nitrate exported from agricultural fields, even in tile-drained watersheds …

Determining The Effects Of Sulfur Fertility Levels On Edamame Soybean [ Glycine Max ( L. ) Merrill ] Protein Components, Theoneste Nzaranyimana

Theses and Dissertations

Edamame [Glycine max (L.) Merr.] a vegetable type soybean is harvested and consumed before reaching its maturity stage (R6). Its health properties drew attention to U.S. consumers because of its high protein content. Proteins are the major structural component of all cells in the living organisms. They are made of essential and non-essential amino acids which play a big role in growth and development and are source of energy. Proteins act as enzymes, antibodies, and hormones and blood protein. Sulfur (S) is a component of the amino acids cysteine (Cys) and methionine (Met) which are the building blocks for proteins. …

Winter Cover Crops Impact On The Distribution Of Soil Inorganic Nitrogen And Subsequent Crop Uptake And Yield Following Fall Applied Anhydrous Ammonium, William Travis Deppe

Theses and Dissertations

The pairing of cover crops with spring application of nitrogen has shown improved nitrogen efficiency in corn production systems. However, studies have shown that only 50% of central Illinois farmers practice spring application of nitrogen. Furthermore, the literature demonstrates that in years with above average rainfall, fall applied N management systems are more susceptible to N loading relative to spring systems. Therefore, the objective of this research was to determine the efficacy of winter cover crops to impact the distribution of soil inorganic N following fall applied anhydrous ammonium. The experimental site is located at the Illinois State University Research …

Plant Functional Trait And Hyperspectral Reflectance Responses To Comp B Exposure: Efficacy Of Plants As Landmine Detectors, Paul V. Manley Ii

Theses and Dissertations

At least 110 million landmines have been planted since the 1970s in about 70 nations, many of which remain in place today. Some risk of detection may be mitigated using currently available remote sensing techniques when vegetation is present. My study focused on using plants as phytosensors to detect buried explosives. I exposed three species representing different functional types (Cyperus esculentus (sedge), Ulmus alata (tree), Vitis labrusca (vine)) to 500 mg kg^-1 of Composition B (Comp B; 60/40 mixture of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT)), a commonly used explosive mixture, and measured functional traits and reflectance over …

Nitrogen Rate Optimization For Grain Yield Within Fall And Spring Applications, Justin Wheeler

Theses and Dissertations

This thesis is a comprehensive analysis of research, investigating the impact of fall and spring applied nitrogen at various rates on the vulnerability of fall applied nitrogen, nitrogen uptake, and corn yields. In addition, optimal nitrogen rates and timing were evaluated across East Central Illinois.

Improving The Efficiency Of Fall Applied N With Cover Crops, Corey Lacey

Theses and Dissertations

Nitrate loss studies in Midwestern tile-drained fields have found that fall applied nitrogen (N) resulted in elevated nitrate concentrations in tile water during both the corn and soybean year of a 2 year rotation. The effectiveness of cover crops to reduce nitrate leaching when N is spring applied has been well demonstrated, however there is a dearth of knowledge on the ability of cover crops to reduce nitrate leaching in a system where N is fall applied. Thus, the objectives of this research were to (i) investigate the efficacy of winter cover crops to reduce nitrate leaching from fall applied …

The Effects Of Planting Techniques On Maize Grain Yield And Silage Production, Tyler D. Kaufman

Theses and Dissertations

This thesis is a comprehensive analysis of the effects of seed orientation, row direction and planting population on grain yield, kernel composition, and silage yield and composition. Producers are striving to increase profit by efficiently using their available land area to maximize crop production. However, little research is available testing the effect of seed orientation on grain or silage production. Quantifying the impacts of seed orientation and row direction on grain and silage is essential for maximum crop production. Dissemination of the results should benefit grain and silage producer.

Two experiments were conducted to evaluate the effects of manipulating seed …

Agronomic Performance Of Five Varieties Of Forage Grasses Inroduced In Carmen Pampa, Province Of Nor Yungas, La Paz, Joel Eliseo Bautista Vargas

Theses and Dissertations

This study was done with the objective of evaluating the agronomic performance of five varieties of forage grasses introduced to the community of Carmen Pampa in the province of Nor Yungas, La Paz from 2005-2006. The average temperature during the study was 11.93ºC and the average precipitation was 801.75 mm. The trial was done with a design of randomized blocks having five species and six repetitions. The species studied were: Panicum virgatum, Sorghastrum nutans, Andropogon gerardii, Tripsacum dactyloides, and Eragrostis curvula. Variables evaluated were: plant height (cm), coverage (%), number of plants, bunches of florets, and dry matter yield (kg/ha). …

Production Of The Edible Mushroom (Agaricus Sp.) Under Laboratory Conditions For Their Multiplication In Different Culture Media, Mercedes Victoria Galeón Alcón

Theses and Dissertations

Edible mushroom production has two different stages: the vegetative stage and the fruiting stage. The vegetative phase is performed in a biotechnology laboratory and covers the technique for obtaining “spawns”, which parameters include the multiplication and reproduction of the mycelium. The fruiting phase begins with the appearance of edible mushrooms and includes everything that occurs outside the laboratory. In our country, production of edible mushrooms is limited and generally unknown. So, in this study, the vegetative phase was divided into two stages and conducted in the laboratory. Stage 1: We inoculated spores and implants of the edible mushroom species Agaricus …

Resistance Of Different Tomato Varieties (Lycopersicon Esculentum) To Late Blight (Phytophthora Infestans) In Laboratory Conditions At Uac Carmen Pampa, In The Province Of Nor Yungas, Department Of La Paz, Andrez Faustino Florez Paxi

Theses and Dissertations

In order to respond to the low economic and harvesting yields caused by diseases that attack the tomato, we considered using tomato varieties resistant to late blight (Phytophthora infestans) of tomato (Lycopersicon esculentum) and potato (Solanum tuberosum). The evaluation of the percentage of infestation was performed with tomato leaflets over a 168 hour period. The percentage of infestation was recorded every eight hours from the time of inoculation until maximum infestation was reached. The methodology applied was at random and included six treatments and five replications. The experiment consisted of collecting healthy leaflets from five improved varieties and one local …

Adaptations Of Five Pale-Type Grain Amaranth Accessions (Amaranthus Caudatus) And Five Ataco Or Sangorache Accessions (Amaranthus Hybridus) In The Cities Of Otavalo And Antonio Ante, Sixto Stalin Tuston Torres

Theses and Dissertations

This study was conducted in two locations: Pucará (2,413m above sea level) and Mojandita (2,922m above sea level), both of which are found in the province of Imbabura, Ecuador. The objectives of this study were to: characterize the morphological and agronomic traits as well as the overall quality of the ten amaranth accessions in this study; identify the accessions with the highest yield and biomass; determine the nutritional characteristics of the experimental accessions; and determine the cost of production of amaranth per hectare. The following null hypothesis was assumed: the agronomic and nutritional characteristics of the ten accessions in this …

Agronomic Evaluation And Comparison Of The Yield Of Six Multiannual Forage Species, Under Dry Land Conditions In The Ingavi Province, Freddy Óscar Paye Paye

Theses and Dissertations

The agronomical evaluation and the comparative work of six multiannual forage species was conducted in the facilities of the Benson Institute, in the community of Contorno de Letanias, Ingavi province, La Paz. The objectives were to evaluate the agronomic behavior, as well as to evaluate the dry matter (DM) yield of six multiannual forage species (grasses) under local conditions, and to determine the partial cost of production of the studied species. The annual mean temperature was 9.14°C, and 517.6 mm of precipitation. The test was conducted under the random block design test, with six different forage species, and three repetitions. …