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Full-Text Articles in Plant Sciences

Nitrogen Application Timing And Cereal Rye (Secale Cereale L.) Cover Crop Influence Greenhouse Gas Emissions, Graig Reicks Jan 2024

Nitrogen Application Timing And Cereal Rye (Secale Cereale L.) Cover Crop Influence Greenhouse Gas Emissions, Graig Reicks

Electronic Theses and Dissertations

Dryland contributions to greenhouse gas (GHG) emissions are increased by N fertilizer applications and high soil water contents. Fertilizer timing and spring growth of cover crops prior to cash crop planting were investigated in separate studies to examine impacts on overall GHG emissions using a near continuous measurement system. There was a significant interaction between N fertilizer rate (0 vs. 224 kg N ha-1 surface-applied as urea) and application date (p= 0.01) for CO2 emissions. This interaction occurred because N fertilizer increased CO2 emissions by 35% for the 21 d interval following early spring application. When application was delayed until …


Integrating Early Season Clover Cover Crops As A Living Mulch In Broccoli And Transitional Organic Winter Squash Production In Eastern South Dakota, Alexis Rose Barnes Jan 2024

Integrating Early Season Clover Cover Crops As A Living Mulch In Broccoli And Transitional Organic Winter Squash Production In Eastern South Dakota, Alexis Rose Barnes

Electronic Theses and Dissertations

Managing weeds, improving soil health, and reducing the use of plastic mulch continue to be priorities for South Dakota vegetable farmers. Farmers have expressed an interest in integrating cover crops into their farm systems. Clover cover crops used as a living mulch within and along cash crop rows may aid in weed suppression, nitrogen fixation, and prevent soil erosion. However, prior research has shown challenges of incorporating living mulch due to yield decreases. Research conducted in 2022 and 2023 in eastern South Dakota investigated the effects of four clover and four in-row soil management treatments on broccoli and organic winter …


The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson Jan 2024

The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson

Electronic Theses and Dissertations

Long-term and intensified agricultural land management has resulted in increased rates of soil erosion and has altered much of the carbon cycle at regional and global scales. Anthropogenic degradation of soil resources is a barrier to sustainable production, soil functioning, and ecosystem services. It is difficult to quantify the scope of pedogenic changes due to the lack of legacy data and short temporal scales. This study utilized decades to century-old soil information to quantify historical soil erosion losses and changes in soil carbon pools of eastern South Dakota soils. The results show that soils in the region have been significantly …


Utilizing Soil Sensors To Assess Soil Health And Investigating Cover Crops Impact On Methane Emission, Shailesh Pandit Jan 2024

Utilizing Soil Sensors To Assess Soil Health And Investigating Cover Crops Impact On Methane Emission, Shailesh Pandit

Electronic Theses and Dissertations

Soil health is influenced by climate change, cultural practices, topography, crop rotations, cover crops, soil parent materials, and soil biota. Interactions between these factors can improve or reduce soil health. This thesis investigates two topics, using soil sensors to provide a rapid assessment of soil health, and the impact of cover crops on soil biological activity and greenhouse gas emissions. Chapter 1 explores the use of two types of sensors to measure apparent electrical conductivity (ECa) and provides examples on the use of these sensors. Even though both sensors measure ECa using different processes, they provide useful information about temporal …


The Relationship Between Soil Test Phosphorus And Soil Biology - A Natural Management Of Soil Phosphorus Through Conservation Practices, Clarence Frederick Winter Jan 2024

The Relationship Between Soil Test Phosphorus And Soil Biology - A Natural Management Of Soil Phosphorus Through Conservation Practices, Clarence Frederick Winter

Electronic Theses and Dissertations

Phosphorus (P) management is an ongoing challenge in modern agriculture. Due to the importance of P in agriculture, P fertilizer additions are made throughout the U.S. to avoid nutrient-depleted soil. However, the application of P is problematic, as an excess of P in an agricultural system elevates the risk of environmental degradation, and current synthetic P sources are a fleeting resource. Additionally, a majority of P found in agricultural soils are insoluble, in the form of secondary and primary P minerals, making this large pool of P unavailable to plants. Fortunately, soil fungi organisms, such as arbuscular mycorrhizal fungi (AMF) …


Plant Pathways Associated With Competition For Soybean Root Colonization By Bradyrhizobium Strains, Athira Sethu Madhavan Jan 2024

Plant Pathways Associated With Competition For Soybean Root Colonization By Bradyrhizobium Strains, Athira Sethu Madhavan

Electronic Theses and Dissertations

Nitrogen is a crucial nutrient for the growth and development of plants. Legume crops like soybeans develop symbiotic associations with soil bacteria from the genus, Bradyrhizobium to obtain fixed nitrogen. In this mutualistic association, rhizobia are released into root nodules that provide a compatible environment for rhizobia to grow and fix nitrogen (Symbiotic Nitrogen Fixation (SNF)). A caveat in such beneficial associations is the competition between different rhizobium strains in soil for infection and nodule occupancy. The elite inoculant strains encounter competition by indigenous rhizobial population in the soil to infect and nodulate a susceptible legume host, because of which …


Ecophysiology Of Bradyrhizobium Diazoefficiens Usda 110, Armaan Kaur Sandhu Jan 2024

Ecophysiology Of Bradyrhizobium Diazoefficiens Usda 110, Armaan Kaur Sandhu

Electronic Theses and Dissertations

With increasing demand for soybean, maximizing plant yield is important yiel is dependent on nitrogen availability, but nitrogen fertilizers can meet the plant's needs but have severe environmental impacts. An economically and environmentally sustainable approach is to enhance nitrogen availability through Biological Nitrogen Fixation by symbiotic rhizobia, Bradyrhizobium, an efficient nitrogen fixer for soybean. This symbiosis begins with attachment of rhizobia to legume roots. Root and rhizobia surface properties play a significant role in this attachment. Another major factor affecting root colonization is bacterial competition ability. There is a lack of knowledge on the role of bacterial surface properties, competition …


Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin Jan 2024

Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin

Electronic Theses and Dissertations

Saline and sodic soils are an increasing concern across the Northern Great Plains (NGP) due to factors of climate change and land management that are drawing geologically derived salts to the land surface. Traditional laboratory assessments, such as electrical conductivity (EC) and sodium adsorption ratio (SAR), are time and resource consumptive. Portable X-ray fluorescence (PXRF) may be a viable proximal sensing alternative, as it is able to provide elemental data in minutes, in situ or ex situ, and can directly quantify salinity-associated elements like Ca, Mg, and S. PXRF paired with predictive models has proven useful for a range of …


Various Surfactant Soil Conditioner Effect On Plant Nutrient Concentration, Soil Nutrient Depletion, Soil Volumetric Water Content, Plant Biomass And Yield In Corn, Timothy Veldkamp Jan 2024

Various Surfactant Soil Conditioner Effect On Plant Nutrient Concentration, Soil Nutrient Depletion, Soil Volumetric Water Content, Plant Biomass And Yield In Corn, Timothy Veldkamp

Electronic Theses and Dissertations

Soil conditioners help improve soil structure by increasing aeration, water infiltration and water holding capacity leading to nutrient availability and reduced irrigation needs. The goal of this study was to evaluate the impact of multiple soil conditioners (SC1, SC2, SC3, SC4, and SC5) on corn (Zea mays L.) and their ability to reduce irrigation by 30%. This was evaluated in the field in 2022 and 2023 by Aurora, SD using a Randomized Complete Block Design with six replications. Conditioners were applied as broadcast pre-emergence treatments with 70% irrigation. Control treatments of 70% and 100% irrigation, respectively were included. SC1 application …


Building No-Tillage Maize Nitrogen Recommendation Algorithm That Considers Improvements In Soil Health, Dwarika Bhattarai Jan 2023

Building No-Tillage Maize Nitrogen Recommendation Algorithm That Considers Improvements In Soil Health, Dwarika Bhattarai

Electronic Theses and Dissertations

In long-term no-till fields, farmers have reported that less N is required to optimize maize (Zea mays L.) yields in long term no-tillage fields than conventional tillage fields. These reductions may be attributed to improved soil health resulting from increasing soil organic matter, higher soil microbial activities, and improved water and nutrient use efficiency. However, the impact of soil health measurements on fertilizer-N requirement has not been determined. The objective of this dissertation was to compare different regional N recommendation models to measured values and develop a maize fertilizer-N recommendation model, using machine learning approaches, that includes adjustments based on …


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. …


Improving The Utility Of Precision Agriculture Through Machine Learning And Climate-Smart Practices, Skye Brugler Jan 2023

Improving The Utility Of Precision Agriculture Through Machine Learning And Climate-Smart Practices, Skye Brugler

Electronic Theses and Dissertations

Climate Smart Practices are management strategies that focus on increasing soil and crop productivity, utilize site-specific strategies to increase resiliency against the effects of climate change, and mitigate these negative effects by reducing greenhouse gas (GHG) emissions. Decision Support Systems (DSSs) using machine learning (ML) can adjust models based on new information and help farmers make climate smart decisions within their operation. The 4R nutrient management model of right source, rate, location, and time also demonstrates a framework that may be considered climate smart by improving soil and crop productivity. However, when initially conceptualized, the 4R model did not consider …


Expanding The Use Of High-Performance Liquid Chromatography For Varietal Identification Or Verification Of Selected Cereal Crops, Johnna Jorgensen Jan 2023

Expanding The Use Of High-Performance Liquid Chromatography For Varietal Identification Or Verification Of Selected Cereal Crops, Johnna Jorgensen

Electronic Theses and Dissertations

High-performance liquid chromatography (HPLC) is a form of analytical chemistry where adsorption is a key factor in which the purpose is to separate, identify and quantify each component in a mixture. It is the optimal separation technique of chemical and biological compounds that are non-volatile including proteins and natural products (i.e., plant extracts). As each sample component interacts differently with the absorbent material within the column, the flow rates change leading to the separation of peaks, which are plotted via computer software. Most commonly HPLC analysis has been used for chemical manufacturing and pharmaceutical purposes. When using HPLC for crop …


Fusarium Head Blight Resistance Assessment In Barley, Tasneem Fathima Jan 2023

Fusarium Head Blight Resistance Assessment In Barley, Tasneem Fathima

Electronic Theses and Dissertations

Fusarium head blight (FHB), commonly called scab is the most devastating disease of wheat and barley caused by the ascomycete fungus, Fusarium graminearum. FHB affects both the quality and quantity of cereal grains affecting the supply chain of the food and feed industry and the marketability of the produce. Barley (Hordeum vulgare L.) is among the several crop species most vulnerable to FHB infection. An estimated 25% of Spring barley grain production in the United States is used to make malted beverages such as beer. Malting barley is a relatively high-value crop with high demands regarding grain quality. FHB directly …


Effect Of Foliar And Preplant Sulfur Application On Soybean Nutrient Uptake, Yield, And Seed Protein And Oil Content, Gena Ram Mahato Jan 2023

Effect Of Foliar And Preplant Sulfur Application On Soybean Nutrient Uptake, Yield, And Seed Protein And Oil Content, Gena Ram Mahato

Electronic Theses and Dissertations

In recent years, Sulfur (S) deficiency has been observed in soybean producing regions in the US and different parts of the world. The major factors behind the frequent occurrence of S deficiency are reduced atmospheric S deposition due to strict regulations on emissions from fossil fuels, large S removal from high yielding crops, less use of fertilizers containing S, and intensive cultivation practices. To test S limitations, I conducted two independent studies from 2019 to 2021 at two locations in Eastern South Dakota to determine the effect of foliar and preplant S application on soybean. The objectives of this research …


Soil Profile Properties And Greenhouse Gas Emissions As Influenced By Long-Term Cattle Manure And Inorganic Fertilizer Applications Under Corn-Soybean-Spring Wheat Rotation In Eastern South Dakota, Anuoluwa Ojonoka Sangotayo Jan 2023

Soil Profile Properties And Greenhouse Gas Emissions As Influenced By Long-Term Cattle Manure And Inorganic Fertilizer Applications Under Corn-Soybean-Spring Wheat Rotation In Eastern South Dakota, Anuoluwa Ojonoka Sangotayo

Electronic Theses and Dissertations

The application of manure and inorganic fertilizer in row crops may significantly influence soil and greenhouse gas (GHG) emissions. Understanding the long-term influence of these management practices on soil pore characteristics, hydro-physical properties and greenhouse gas emission is essential in developing proper conservation practices. However, there is limited information on the impact of cattle manure and inorganic fertilizer application on soil hydro-physical properties, soil pore characteristics at lower depths and surface GHGs emissions. Therefore, the objectives of this study were to; (i) utilize X-ray computed tomography (XCT) technique to quantify the impact of manure and fertilizer amendments under a corn …


Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel Jan 2023

Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel

Electronic Theses and Dissertations

Understanding soil N transformations in agricultural systems of the Northern Great Plains is crucial for guiding effective soil and nutrient management of this vital cropland. While the use of biochar in agriculture has attracted great attention recently, little has been reported on the seasonal dynamics of soil nitrogen (N) transformation and its response to biochar application. A field experiment was conducted over 2 seasons, spring (6/3/19-6/24/19) and summer (7/26/19-8/16/19), using four treatments or control soil, urea (224 kg N/ha), biochar (46,250 kg/ha), and urea+biochar (224 kg N/ha and 46,250 kg/ha, respectively). The results for both seasons showed biochar had no …


Identifying Optimum Germination Temperatures And Analysis Weights In Seed Testing For Stiff Goldenrod (Solidago Rigida) And River Bulrush (Bolboschoenus Fluviatilis), Rachel Geary Jan 2023

Identifying Optimum Germination Temperatures And Analysis Weights In Seed Testing For Stiff Goldenrod (Solidago Rigida) And River Bulrush (Bolboschoenus Fluviatilis), Rachel Geary

Electronic Theses and Dissertations

Federal and state seed laws require seed lots offered for sale to be tested and labeled with the appropriate information before they can be sold. Those tests are conducted in seed testing labs all around the world. In the United States, accredited seed testing labs follow the Association of Official Seed Analysts (AOSA) Rules for Testing Seeds to provide information for labeling. The rules lack instructions for weights and germination for many native species. Stiff goldenrod (Solidago rigida) and river bulrush (Bolboschoenus fluviatilis) are two species that lack any information required for testing. When seed testing labs use correct weights …


The Effects Of Residue Amounts And Variety Selection On The Development Of Wheat Fungal Pathogens In South Dakota, Abrielle Tembreull Jan 2023

The Effects Of Residue Amounts And Variety Selection On The Development Of Wheat Fungal Pathogens In South Dakota, Abrielle Tembreull

Electronic Theses and Dissertations

Roughly 50% of South Dakota cropland is under the practice of no-till, with large increases in acres of no-till in the last 20 or so years. No-till is beneficial for Great Plains states, such as South Dakota, as soil residues are withheld. Residues are shown to increase soil health through retention of moisture and increase of microorganisms, but residues can serve as a source of inoculum for fungal pathogens that can overwinter on them. As wheat is one of the most important food crops in the world, it is important to protect this vital crop from diseases. Diseases of wheat …


Fungicide Sensitivity In P. Tritici-Repentis Diverse Population And Phenotyping Of Spelt Wheat For Multiple Diseases, Zunera Shabbir Jan 2023

Fungicide Sensitivity In P. Tritici-Repentis Diverse Population And Phenotyping Of Spelt Wheat For Multiple Diseases, Zunera Shabbir

Electronic Theses and Dissertations

Pyraclostrobin, a QoI fungicide, is extensively used in the management of fungal leaf spot diseases. In this study, 215 P. tritici-repentis isolates collected from wheat fields in South Dakota were evaluated for their sensitivity to Pyraclostrobin. Of 215 isolates, 48 isolates (22%) exhibited insensitivity based on G143A mutation and EC50 values using spore germination assay. Our results indicate reduced sensitivity to insensitivity to pyraclostrobin in some isolates suggesting regular monitoring of the P. tritici-repentis population to QoI fungicides is essential to track the evolution of insensitive population. Spelt wheat (Triticum spelta L.) is an ancient cereal that is gaining small …


Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden Jan 2023

Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden

Electronic Theses and Dissertations

Regenerative agriculture is a pressing matter for the dairy industry to address cropland sustainability and carbon sequestration. One regenerative management practice that has been identified to help with row crop sustainability for key metrics like soil organic carbon (SOC) is complex covers. When producers use complex covers one of the main challenges is that it takes time to detect a change in SOC. However, simulation models are a tool that can be used to help determine if a regenerative practice is a strategy that gives the best results (i.e., increased SOC) while aligning with long-term production goals. Therefore, our objectives …


Genomics-Assisted Approaches To Improve Grain Yield And End-Use Quality In Hard Winter Wheat (Triticum Aestivum L.), Harsimardeep Singh Gill Jan 2023

Genomics-Assisted Approaches To Improve Grain Yield And End-Use Quality In Hard Winter Wheat (Triticum Aestivum L.), Harsimardeep Singh Gill

Electronic Theses and Dissertations

Global wheat production needs to be increased by 60% to meet the future demand of feeding nine billion people by 2050. Simultaneously, it is important to improve the enduse quality to meet the requirements of producers, grain markets, processors, and consumers. Thus, the development of more productive wheat varieties with better enduse quality remains the primary focus for all wheat breeding programs. However, direct phenotypic selection for improving grain yield and end-use quality is difficult as it is highly influenced by environmental factors. This dissertation focuses on harnessing advancements in genomics applications, including genome-wide association studies (GWAS), for the genetic …


Phosphate2 And Pin-Likes7 Affect Symbiotic Nodule Phenotypes In Soybean, Bhawandeep Kaur Jan 2023

Phosphate2 And Pin-Likes7 Affect Symbiotic Nodule Phenotypes In Soybean, Bhawandeep Kaur

Electronic Theses and Dissertations

Legumes and soil rhizobia share a symbiotic relationship, wherein rhizobia fix atmospheric dinitrogen in exchange for photosynthates from the host plant. This exchange of mutual benefits occurs in a specialized root structure called ‘nodule’. Soybean (Glycine max) nodules arise from root outer cortical cells. De novo cell differentiation of cortical cells during nodule development leads to the formation of two distinct nodule zones in the mature nodule: the central infection zone where nitrogen fixation occurs and the peripheral parenchyma zone that houses vascular bundles. Plant signaling mechanisms that dictate the development of these nodule zones are not known. To address …


Phomopsis Stem Canker Of Sunflower (Helianthus Annuus L.): Etiology And Epidemiological Conditions Affecting Endophytic Population Of Diaporthe Spp., And Fungicide Efficacy, Nabin Kumar Dangal Jan 2022

Phomopsis Stem Canker Of Sunflower (Helianthus Annuus L.): Etiology And Epidemiological Conditions Affecting Endophytic Population Of Diaporthe Spp., And Fungicide Efficacy, Nabin Kumar Dangal

Electronic Theses and Dissertations

Phomopsis stem canker (PSC), caused by species of Diaporthe, is a major disease of sunflower (Helianthus annuus L.) in the U.S., which can cause yield loss over 40%. The disease prevalence increased since 2010 in the major sunflower producing U.S. states of Nebraska, Minnesota, North Dakota, and South Dakota. Previous studies on the use of foliar fungicides in managing Phomopsis stem canker indicated mixed results on their efficacy in disease reduction and yield gain. Additionally, we do not have sufficient information on asymptomatic colonization by endophytic Diaporthe on sunflower tissue and how foliar fungicide and weather parameters affect the prevalence …


Response Of Soil Biochemical And Physical Properties To Long Term Prairie Cordgrass And Kura Clover Intercropping System, Vaishnavi Varikuti Jan 2022

Response Of Soil Biochemical And Physical Properties To Long Term Prairie Cordgrass And Kura Clover Intercropping System, Vaishnavi Varikuti

Electronic Theses and Dissertations

Prairie cordgrass (Spartina pectinata) (PCG) is a warm-season perennial grass that can be used as a biofuel feedstock and can be grown on marginal lands. Previous studies on intercropping of a perennial legume i.e., kura clover (Trifolium ambiguum) (KC) with PCG can improve soil biochemical properties, increase biomass production, mitigate greenhouse gas (GHG) emissions while reducing the chemical fertilizer requirement. However, there is a lack of evidence about the effects of PCG production on soil biochemical and physical properties during the cropping season and at deeper soil depths in reference to support plant growth, environmental implications and enhance the soil …


Soil Hydro-Physical Properties, Computed Tomography Measured Pore Parameters, And Soil Health Indicators As Influenced By Tillage And Crop Rotation Systems, Goutham Thotakuri Jan 2022

Soil Hydro-Physical Properties, Computed Tomography Measured Pore Parameters, And Soil Health Indicators As Influenced By Tillage And Crop Rotation Systems, Goutham Thotakuri

Electronic Theses and Dissertations

Long-term tillage and crop rotation systems are important agricultural management practices as these can have direct impact on the soil’s key properties. The objectives of this study were to (ⅰ) quantify the soil pore characteristics under long-term tillage and crop rotation using X-ray computed tomography (XCT) and to assess the relationships between XCT-measured pore parameters and soil hydro-physical properties; and (ⅱ) evaluate the impacts of long-term tillage and crop rotation on select soil health indicators. The objective (ⅰ) was carried out at Haskell Agricultural Laboratory (HAL), Concord, NE; and objective (ⅰi) was carried out at South Central Agricultural Laboratory (SCAL), …


It's Not Just No-Till: Crop Rotations Are Key To Improving Soil Quality And Grain Yields At Dakota Lakes Research Farm, Natalie Sturm Jan 2022

It's Not Just No-Till: Crop Rotations Are Key To Improving Soil Quality And Grain Yields At Dakota Lakes Research Farm, Natalie Sturm

Electronic Theses and Dissertations

No-till is increasingly promoted as a vital agricultural practice to address the challenge of improving soil quality while maintaining the ability to produce food, feed, fuel, and fiber. However, questions remain regarding 1) how different crop rotations impact soil quality under no-till management specifically and 2) whether significant improvements in soil quality can be made without negatively impacted crop yields. In this study, we demonstrate that even under the same long-term no-till management, differences in grain yields and soil biological, chemical, and physical properties exist between crop rotations at Dakota Lakes Research Farm in central South Dakota. We propose that …


Evaluating Fungicide Timing, Efficacy, And Sensitivity As Well As Candidate Resistance Genes Against Fungi Causing Phomopsis Stem Canker In Sunflower, Ruchika Kashyap Jan 2022

Evaluating Fungicide Timing, Efficacy, And Sensitivity As Well As Candidate Resistance Genes Against Fungi Causing Phomopsis Stem Canker In Sunflower, Ruchika Kashyap

Electronic Theses and Dissertations

Phomopsis stem canker is one of the major diseases of sunflower (Helianthus annuus L.) caused by complex of Diaporthe spp., in the U.S. This disease became of economic importance after 2010 epidemic in Minnesota, North Dakota, and South Dakota and since then the prevalence of this diseases has increased due to increased average precipitation in these major sunflower growing regions of the U.S. The two important disease management strategies involve the use of fungicides and partially resistant hybrids. However, over the years, researchers and growers have seen varied results on Phomopsis stem canker disease severity reduction and yield gains, when …


Genome-Wide Association Mapping And Genomic Prediction For Enhancing Fhb Resistance In Hard Winter Wheat, Jinfeng Zhang Jan 2022

Genome-Wide Association Mapping And Genomic Prediction For Enhancing Fhb Resistance In Hard Winter Wheat, Jinfeng Zhang

Electronic Theses and Dissertations

Wheat is one of the most important staple crops providing 20% of energy for 35% of the world population. Fusarium head blight (FHB), primarily caused by the fugal Fusarium graminearum Schwabe, is a damaging disease in wheat that affects global wheat production every year and causes food safety issues. The disease not only reduces the grain yield and quality but also produces mycotoxin in the diseased kernels making them unsuitable for human consumption or as livestock feeds. Breeding FHB resistant cultivar is the most effective and economical approach to managing the disease. This study combines genome-wide association study (GWAS) and …


Study Of Root System Architectural Traits Of Oat And Response To Endophyte Inoculation And Drought Stress, Krishna Ghimire Jan 2022

Study Of Root System Architectural Traits Of Oat And Response To Endophyte Inoculation And Drought Stress, Krishna Ghimire

Electronic Theses and Dissertations

Oat is an important cereal crop grown worldwide. Oats have the potential to contribute to human health due to their unique nutritional attributes. Developing oat cultivars with efficient root systems able to extract heterogeneously distributed soil resources can help maintain yield under drought conditions and in nutrient poor soil. Various root traits determine the soil volume that is explored by the root system for resource acquisition. Knowledge about the genetic control of oat root traits and response to biotic and abiotic environmental factors is lacking. Identifying quantitative trait loci associated with root traits and understanding the response of roots to …