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Full-Text Articles in Life Sciences

Machine-Learning And Meta-Analysis Techniques To Quantify And Predict Soil Organic Carbon, N2O-N And Co2-C Emissions In Cover Crop Systems, Deepak Raj Joshi Jan 2022

Machine-Learning And Meta-Analysis Techniques To Quantify And Predict Soil Organic Carbon, N2O-N And Co2-C Emissions In Cover Crop Systems, Deepak Raj Joshi

Electronic Theses and Dissertations

People worldwide are challenged by multiple threats including climate change, growing populations, and soil degradation. Addressing these challenges requires understanding of the local environment, farming systems and modern technologies. These technologies include new ways to process information that include artificial intelligence, machine learning and meta-analysis. Models produced using these technologies may be useful for predicting the consequences of implementing conservation practices that reduce GHG emissions as well as for determining the carbon footprint of cropping systems that include environmentally friendly conservation technologies such as growing cover crop. Therefore, our objectives of this study were to: 1) provide an overview of …


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 …


Efficacy Of Nanomaterials And Biorationals On The Bacterial Leaf Streak Management In Wheat, Abraham Hangamaisho Jan 2022

Efficacy Of Nanomaterials And Biorationals On The Bacterial Leaf Streak Management In Wheat, Abraham Hangamaisho

Electronic Theses and Dissertations

Wheat (Triticum aestivum L.) is one of the most important cereal crops in the United States. Most wheat varieties are susceptible to bacterial leaf streak (BLS), a major disease caused by Xanthomonas translucens pv. undulosa (Xtpvu). BLS is challenging to manage since common chemicals do not provide adequate control. Nanomaterials and plant extracts have shown potential to provide a sustainable environmentally friendly control of animal and plant diseases. However, limited data are available on the efficacy of plant extracts and nanomaterials controlling BLS in wheat. The objective of this study was to evaluate the antibacterial activity of plant extracts and …


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 …


Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis Jan 2022

Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis

Electronic Theses and Dissertations

Phosphorus (P) pollution has become a concern among multiple scientific organizations as it leads to eutrophication, an algal bloom that depletes lacustrine and marine ecosystems of native species. Multiple strategies can be implemented to reduce phosphorus loss from agriculture fields, which is often implicated as a cause of eutrophication. Soil phosphorus chemistry results in phosphate fertilizers absorbing to clay minerals over time. Soil phosphorus is lost from agricultural fields primarily through wind and water erosion. No-till practices prevent soil erosion, which reduces the phosphorus from loading into waterways. Fertilizer placement affects phosphorus loss. Surface application of phosphorus fertilizers increases the …


Combining Soil Health And Fertility Measurements To Improve The Accuracy Of Predicting Corn Grain Yield Responses To P And K Fertilization, Benjamin Groebner Jan 2022

Combining Soil Health And Fertility Measurements To Improve The Accuracy Of Predicting Corn Grain Yield Responses To P And K Fertilization, Benjamin Groebner

Electronic Theses and Dissertations

Researchers have pointed to changes in climate and land management practices to justify the need to reevaluate the accuracy of current South Dakota (SD) corn (Zea mays L.) P and K fertilizer recommendations. Also, an increase in soil health understanding has created the potential for soil health measurements to be used to improve the accuracy of these recommendations. The objectives for this study were to 1) evaluate the current P and K critical values and 2) determine the effect of including soil health indicators on improving fertilizer recommendation accuracy. This project was conducted throughout central and eastern SD from 2019-2021 …


Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain Jan 2022

Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain

Electronic Theses and Dissertations

Conservation management practice adoption on agricultural land has increased in recent years due to increasing public and private investment. The anticipated impact of increasing conservation management practice adoption are reduced greenhouse gas emissions and improved soil, water, and air quality. Understanding how these conservation management practices affect agricultural producers economically is vital to properly incentivize these practices. The existing literature on how conservation management practices affect soil health and crop yields is mixed and generally has been conducted on experimental research stations. These studies may not fully account for the on-farm effects of conservation management practices. The objectives of this …


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 …


Design Of Affordable Polyaniline - Based Wearable Sensor For Real Time Plant Growth Monitoring, Temitope Borode Jan 2022

Design Of Affordable Polyaniline - Based Wearable Sensor For Real Time Plant Growth Monitoring, Temitope Borode

Electronic Theses and Dissertations

The need for precision agriculture in today and future farming cannot be overstressed. Recent agriculture is characterized by numerous challenges such as environmental stressors and resource constraints resulting in low crop yield and unsustainable agriculture practices. Understanding plant growth mechanism and growth rate under the external influence is a bedrock towards precision agriculture practices ensuring optimum yield and sustainable utilization of resources. The current study addresses this need by developing and applying an affordable and stable sensor for monitoring plant growth. The sensor was fabricated by in-situ chemical polymerization of aniline on an elastic band substrate by dip coating. The …


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 …


Effect Of Essential Oils In The Control Of Fungal Diseases In Small Grains, Esneider Mahecha Bojaca Jan 2022

Effect Of Essential Oils In The Control Of Fungal Diseases In Small Grains, Esneider Mahecha Bojaca

Electronic Theses and Dissertations

Spring wheat (Triticum aestivum L.) and oats (Avena sativa L.) are important crops due to their high consumption in our daily diet worldwide. They are the main food of consumption per capita due to the high amino-acid content as well of vitamins. However, grain production is limited due to the negative impact of the diseases that cause significant yield loss. Diseases in oats, such as crown rust caused by Puccinia coronata f. sp. avenae (Pca), and in wheat such as Fusarium head blight (FHB) caused by the fungus Fusarium graminearum. Foliar diseases such as tan spot incited by the fungi …


Northern Great Plains Saline Sodic Soil Development, Classification, Remediation, And Management., Shaina Westhoff Jan 2022

Northern Great Plains Saline Sodic Soil Development, Classification, Remediation, And Management., Shaina Westhoff

Electronic Theses and Dissertations

Soil salinity and sodicity are issues of growing concern in the United States (U.S.) and globally. Knowledge gaps for glaciated, dryland salt-affected soils exist because much original salinity and sodicity research focused on irrigated systems. Land managers are being asked to produce food, feed, fiber, and fuel for an expanding global population. The number of land managers and crop advisors who are affected by these soils is increasing. Addressing salinity and sodicity knowledge gaps will be critical for their success. Salinity and sodicity have been impeding crop productivity since the advent of cultivation. Saline and sodic soils form via multiple …


Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels Jan 2022

Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels

Electronic Theses and Dissertations

Conventional agricultural practices can have unintended consequences on the environment and wildlife. Insects and birds are declining at rapid rates around the world, and the current conventional agricultural paradigm is a major driver through habitat loss and the intensification of production. Invertebrates in agroecosystems provide services to both farmers and the rest of society. Regenerative systems may promote the functioning of an agroecosystem by influencing invertebrate abundance, diversity, and ecosystem services and mitigate bird and insect declines through conservation practices that increase soil health, reduce disturbances, and increase biological diversity. Here I address knowledge gaps of the effects of regenerative …


Development Of Genomic Resources In Vitis Riparia For Discoveries On Pre- And Post-Transcriptional Molecular Regulators Of Early Induction Into Endodormancy, Michael Robben Jan 2022

Development Of Genomic Resources In Vitis Riparia For Discoveries On Pre- And Post-Transcriptional Molecular Regulators Of Early Induction Into Endodormancy, Michael Robben

Electronic Theses and Dissertations

Grapevine is one of the most important fruit crops in the world, responsible for billions in global sales annually. The largest threat to grapevine and other crop production is global climate change resulting human activities. This brings unpredictable and drastic changes in ambient air temperatures to many climates in which grapes are grown. Lower temperatures and inclement weather are already responsible for millions in lost revenue due to tissue damage of established plants. Thus, protecting grapevine crops from weather-related damage is the biggest concern to growers aside from pathogen- and diseaserelated crop damage. The primary mechanism for winter survival in …


Identifying Sources Of Resistance And Fungicide Efficacy Against Fungi Causing Phomopsis Stem Canker In Sunflower, Renan Guidini Jan 2022

Identifying Sources Of Resistance And Fungicide Efficacy Against Fungi Causing Phomopsis Stem Canker In Sunflower, Renan Guidini

Electronic Theses and Dissertations

Phomopsis stem canker is a major threat to sunflower (Helianthus annuus L.) production worldwide and its prevalence has increased from 1.5% in 2001 to 61.0% in 2015 in the sunflower producing U.S. states of Colorado, Kansas, Minnesota, Nebraska, North Dakota, South Dakota, and Texas. The disease causes early senescence and lodging of sunflower plants resulting in yield losses up to 40% and oil content up to 25%. Several species of Diaporthe have been reported to cause Phomopsis stem canker. In the United States, Diaporthe helianthi Munyt.-Cvetk. et al. and D. gulyae Shivas et al., have been reported as predominant causal …


E. Coli Persister Cell Survival And Rhizobia Attachment To Soybean Roots, Tanim Islam Jan 2022

E. Coli Persister Cell Survival And Rhizobia Attachment To Soybean Roots, Tanim Islam

Electronic Theses and Dissertations

The theme of this thesis revolves around how bacteria respond and thrive during stress. Chapters 1-3 are about how bacteria deal with life-threatening antibiotics. Chapter 4 covers new research on how bacteria can move from a stressful individual lifestyle (free-living bacteria) to initiating a symbiotic relationship with a plant (a less stressful lifestyle). In Chapter 1, I briefly summarize the current state of knowledge in the field of antibiotic resistance and persistence. In Chapter 2, I add to this knowledge by providing new insights into several antibiotics' potency and exploring the antibiotic Eagle effect. In Chapter 3, I use pyruvate …


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), …


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 …


Exploring Bioprocessing Technologies For Diverse Industrial Application Of Canola, Ahmad Fawzi N Alhomodi Jan 2022

Exploring Bioprocessing Technologies For Diverse Industrial Application Of Canola, Ahmad Fawzi N Alhomodi

Electronic Theses and Dissertations

Globally, canola is the second largest oilseed crop after soybean, which is processed for the commercial production of high value oil. The industrial processing steps for canola oil extraction include preprocessing (cleaning, pressing, flaking, and cooking), mechanical pressing, and/or organic solvents. This process results in large quantities of protein-rich (~ 40% dry basis) meal as a co-product. The meal is used partially in animal diet (<30% inclusion) due to high levels of antinutritional factors (ANFs) such as high fibers, phytic acid, and glucosinolates, and low metabolizable energy. Thus, this research was designed to examine various bioprocessing technologies (i.e., traditional sprouting, solid state fermentation, submerged state fermentation, co-culture fermentation, mild pretreatments, and their combinations) for possible advancement in canola use. Canola seed sprouting for 6-day period led to an increase in protein content and a reduction in ANFs and oil content of sprouts compared to ungerminated seed. Subsequent submerged state fermentation of 6- day old sprouts using three different strains (Aureobasidium pullulans, Trichoderma reesei and Neurospora crassa) further increased protein content and lowered ANFs. Solid-state fermentation of 144 h old sprouts using A. pullulans, N. crassa and T. reesei enhanced the protein content and reduced ANFs of sprouts. Sprouting canola seed for three days helped in hull removal, leading to high protein meal accompanied by low fiber and phytic acid level. Three-day seed sprouting had no effect on oil yield, but free fatty acid content was higher compared to seed oil. Co-culture fermentation of HECM under solid state process showed maximum reduction in fiber content with co-culture of A. pullulans and N. crassa while a combination of A. pullulans and T. reesei promoted the highest GLS and phytic acid reductions compared to other combinations, which indicated the advantage of coculture inoculation over monoculture in terms of ANFs reduction. Mild pretreatment of HECM using deionized water resulted in washed HECM (WHECM) with lower soluble sugars and GLS compared to untreated HECM, whereas protein and amino acid were concentrated due to the removal of soluble components. WHECM compared to HECM showed higher protein digestibility when fed to rainbow trout. Subsequent mono- and coculture fermentation of HECM and WHECM under submerged process resulted in higher protein and amino acid content and lower ANFs levels compared to uninoculated controls. The results of cellulase, endoglucanase and β-glucosidase activity indicated the crucial role of used substrates, fungi, fermentation modes (solid state/submerged stated) and inoculation methods (mono-/co-culture) on enzyme activities.


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 …


Genome-Wide Identification Of Wrky Transcription Factor Encoding Genes In Amborella Trichopoda Baill. (Amborellaceae), Bijaya Pradhan Jan 2022

Genome-Wide Identification Of Wrky Transcription Factor Encoding Genes In Amborella Trichopoda Baill. (Amborellaceae), Bijaya Pradhan

Electronic Theses and Dissertations

WRKY transcription factors (TFs) are DNA-binding proteins, which play important roles in managing plant stresses and regulating growth and development processes. The WRKY TF family has expanded significantly through genome/gene duplications in the plant evolutionary process. Although the WRKY TFs have been identified in hundreds of plant species, they are yet to be identified in Amborella trichopoda, a species that represents the most basal group of Angiosperms. The main objectives of this study were to conduct genome-wide identification of the WRKY gene family in A. trichopoda and to assess their homologs in Angiosperms. In this study, we identified …