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Full-Text Articles in Life Sciences

Modeling Soil Organic Carbon In Select Soils Of Southeastern South Dakota, Shaina Westhoff Jan 2018

Modeling Soil Organic Carbon In Select Soils Of Southeastern South Dakota, Shaina Westhoff

Electronic Theses and Dissertations

Soil organic matter (SOM) is composed of living biomass, dead plant and animal residues, and humus. Humus is a class of complex, organic molecules that are largely responsible for improving soil water holding capacity, nutrient mineralization, nutrient storage, and other critical soil functions. Soil organic carbon (SOC) accounts for approximately 60 percent of SOM and thus SOC is recognized as a strong indicator of soil health. Land use changes and intense cultivation of arable soils in the United States over the past century have led to large decreases in SOM. The objective of this research was to develop a multiple …


Stability Analysis Of Immunogenic Gliadin Accumulation In Hard Red Spring Wheat (Triticum Aestivum L.), Stacy Lindblom-Dreis Jan 2018

Stability Analysis Of Immunogenic Gliadin Accumulation In Hard Red Spring Wheat (Triticum Aestivum L.), Stacy Lindblom-Dreis

Electronic Theses and Dissertations

Misconceptions regarding plant breeding objectives have led to speculation regarding the increasing prevalence of gluten intolerance, wheat allergy, and celiac disease. It is thought that contemporary wheat cultivars accumulate more immunogenic proteins than older cultivars because of supposed genetic changes effected through plant breeding strategies. This study evaluated the stability of gliadin accumulation in 191 hard red spring wheat cultivars grown in 12 location-years. Two enzyme-linked immunosorbent assays (ELISAs) were developed. A paired t test (N = 34) failed to find a statistically significant difference between the experimental ELISAs and the commercial R5 assay measures of mean gliadin (t = …


Expression Analyses And Identification Of Key Molecular Participants In Plant Responses To Environmental Cues, Praveena Kanchupati Jan 2018

Expression Analyses And Identification Of Key Molecular Participants In Plant Responses To Environmental Cues, Praveena Kanchupati

Electronic Theses and Dissertations

Plants constantly engage and interact with the environment and respond to the changes in conditions like temperature, water, and photoperiod, by regulating expression of genes of multiple regulatory and signaling pathways. Insight into these pathways and their participants has provided and will provide candidates to improve various agronomically important traits in crops through marker-assisted breeding and genetic manipulation. With this aim in mind, in the present study, I attempted to identify key candidate genes that are involved in the regulation of; i) plant response to low temperature stress, ii) plant roots’ response to soil moisture content and iii) flowering time. …


Quantifying The Short-Term Impacts Of Cover Crops And Grazing On Soil Health Under An Integrated Crop-Livestock System In South Dakota, Vishal Seth Jan 2018

Quantifying The Short-Term Impacts Of Cover Crops And Grazing On Soil Health Under An Integrated Crop-Livestock System In South Dakota, Vishal Seth

Electronic Theses and Dissertations

Cover crops and grazing under Integrated Crop-Livestock System (ICLS) can impact the rhizosphere nutrient cycling and may have potential to increase the long-term sustainability and economic profitability of agricultural production system. In South Dakota, crop production practices and livestock husbandry are both common which provide the opportunity for ICLS to be successful in this region. However, little is known about the impacts of the cover crops and grazing under ICLS on soil properties in this region. The present study was conducted at South Dakota State University Research Farm (44°20'34.8"N, 96°48'14.8"W), Brookings, SD, to quantify the impacts of cover crops and …


Air-Propelled Organic Fertilizer Grits Can Be Used To Control Weeds And Provide Nitrogen, Michael Carlson Jan 2018

Air-Propelled Organic Fertilizer Grits Can Be Used To Control Weeds And Provide Nitrogen, Michael Carlson

Electronic Theses and Dissertations

Weeds are one of the biggest challenges for organic growers because of the alternative weed control methods. Air-propelled abrasive grit management has been reported to control weed seedlings in corn and soybeans while maintaining yield. This research examined the weed control, corn and soybean yields, nitrogen mineralization, and nitrogen yield responses from grits. The grits used in this research included: Phytaboost Plant Food 7-1-2 (soybean meal), Sustane 8-2-4 and 4-6-4 (turkey litters), and two non-fertilizer grits: Agra Grit (walnut shells) and corn cob meal. Field studies were conducted from 2015 to 2017 in Aurora, SD, Beresford, SD and Morris, MN. …


Land Use Change Sustainability And Carbon Turnover Rate In The Northern Great Plains Soil, Deepak Raj Joshi Jan 2018

Land Use Change Sustainability And Carbon Turnover Rate In The Northern Great Plains Soil, Deepak Raj Joshi

Electronic Theses and Dissertations

Sustainable land management involves the management of land, water, biodiversity and other resources that meet human requirements while maintaining ecosystem services. In the northern Great Plains (NGP), the combined impacts of landuse and climate variability have placed many soils at the tipping point of sustainability. The objectives of this study were to: 1) calculate land-use changes from 2006 to 2012 and from 2012 to 2014 in South Dakota and Nebraska; 2) assess if land use changes had impacted on soil sustainability; 3) calculate variation in total carbon budget and turnover due to seasonal climate variability, biomass quality and soil properties; …


Palmer Amaranth In South Dakota: Growth, Herbicidal Control, And Soybean Yield Loss, Brian Van De Stroet Jan 2018

Palmer Amaranth In South Dakota: Growth, Herbicidal Control, And Soybean Yield Loss, Brian Van De Stroet

Electronic Theses and Dissertations

Palmer amaranth is a growing concern in the United States. Previously thought to only be able to occupy the southern United States, this plant can now be found throughout the northern states as well. Infestations of Palmer amaranth can now be found in South Dakota and is raising many concerns. Palmer amaranth is characterized by large growth and can be highly competitive with many important crops. Soybean is an important crop in South Dakota, as well as the rest of the world, and has not escaped the detrimental aspects of an infestation of Palmer amaranth. The objectives of this study …


Insecticidal Seed And In-Furrow Treatment Recommendations For Soybean And Sunflower, Brady Hauswedell Jan 2018

Insecticidal Seed And In-Furrow Treatment Recommendations For Soybean And Sunflower, Brady Hauswedell

Electronic Theses and Dissertations

Throughout the 2016 and 2017 growing season, field research experiments were replicated across South Dakota. Many times seed treatments are used prophylactic, which is neither good for the producers or the environment. Producers will be able to reduce production costs, if they only use a seed treatment when necessary. The purpose of the first experiment was to determine the effects of seed treatments in combination with planting date and seeding rate on soybean yield. To determine the effects, two years of field data from four eastern South Dakota locations were compared. Within each year and location we compared two planting …


Assessment And Development Of Cold Temperature Germination Tolerance In Oat And Hard Red Spring Wheat, Jacob Baustian Jan 2018

Assessment And Development Of Cold Temperature Germination Tolerance In Oat And Hard Red Spring Wheat, Jacob Baustian

Electronic Theses and Dissertations

Oat (Avena Sativa) and hard red spring wheat (HRSW; Triticum aestivum L.) are both spring planted cereal crops that yield best when planted early in the spring. These crops would benefit from improvements in cold temperature germination tolerance (CTGT) by allowing them faster and more uniform germination and emergence early in the spring. This study aimed to (i) evaluate germination in oat genotypes over a range of sub-optimal temperatures and (ii) establish a methodology for selection of hard red spring wheat for CTGT. Seed samples of ten different oat genotypes were evaluated for CTGT in a germination chamber …


Soybean Aphid Biotype 4 Resistance In Soja And Soybean Plant Introductions, Sophia R. Conzemius Jan 2018

Soybean Aphid Biotype 4 Resistance In Soja And Soybean Plant Introductions, Sophia R. Conzemius

Electronic Theses and Dissertations

Soybean aphid, Aphis glycines Matsumura, is a major pest to soybean, Glycine max (L.) Merr. Host plant resistance is a management tactic that uses naturally occurring soybean plant defenses to limit soybean aphid pest damage. Virulent soybean aphid biotypes are able to successfully colonize on certain aphid resistant soybean. Soybean aphid biotype 4 is most virulent, overcoming all commercially available soybean aphid resistant soybeans (Rag1, Rag2, and Rag1+Rag2). Additional sources of resistance to avirulent biotypes have been identified in soja and soybean plant introductions (PIs). This study examined those resistant soja and soybean for resistance to the newly found soybean …


Greenhouse Gas Emissions From Soil Applied Nitrogen Fertilizers, Samuel Thies Jan 2018

Greenhouse Gas Emissions From Soil Applied Nitrogen Fertilizers, Samuel Thies

Electronic Theses and Dissertations

Greenhouse gases (GHG) absorb and emit radiant energy in the thermal range. Their concentrations in the atmosphere are increasing and becoming an ever increasing issue as the Earth’s average temperature continues to rise. Agricultural practices, such as applying nitrogen fertilizer to increase crop yield can be a major source of GHG emissions and methods are needed to decrease these emissions. The measurements of GHG emissions have been difficult, expensive, and erratic. However, advancing technologies have increased the accuracy and confidence in measuring GHG emissions. The objectives of this study were to determine the 1) effects of different nitrogen fertilizer sources, …


Genetic Component Effects Of Two Loci On Seed Dormancy, Awn, Low-Temperature Germination, Plant Height, And Flowering Time In Rice (Oryza Sativa L.), Ugur Korkmaz Jan 2018

Genetic Component Effects Of Two Loci On Seed Dormancy, Awn, Low-Temperature Germination, Plant Height, And Flowering Time In Rice (Oryza Sativa L.), Ugur Korkmaz

Electronic Theses and Dissertations

Seed dormancy (SD) is an adaptive trait of both ecological and agricultural importance. Cereal crops have been selected for reduced SD to promote germination, which also caused the pre-harvest sprouting (PHS) problem in crop production. The previous research identified a set of quantitative trait loci (QTL) for SD, including qSD1- 2 and qSD8, in the conspecific weedy and cultivated rice (Oryza sativa). qSD1-2 carries a dormancy-enhancing allele from the cultivated rice and has a pleiotropic effect on plant height. qSD8 carries a dormancy-enhancing allele from the weedy rice and tightly links to qAL8 for awn length. The …


Soybean Iron Deficiency Chlorosis: Quantitative Trait Locus Validation And Grain Yield Evaluation, Ahmed Charif Jan 2018

Soybean Iron Deficiency Chlorosis: Quantitative Trait Locus Validation And Grain Yield Evaluation, Ahmed Charif

Electronic Theses and Dissertations

Soybean production in most of the Northern Great Plain area has been challenged by iron deficiency chlorosis (IDC), which is a physiological problem with a plant grown in high pH, calcareous soil. Developing IDC-resistant cultivars is the best approach to meet this challenge. Currently, this approach is limited by lack of knowledge about genetic resources and mechanisms for resistance to IDC. The objectives of this research were to validate quantitative trait loci (QTL) associated with IDC and to evaluate the effect of IDC on yield in soybean cultivars. To validate the QTL, a population of 201 recombinant inbred lines, which …


Efficacy Of Seed Treatments, Microbial And Biochemical Pesticides For Managing Early Tan Spot And Stripe Rust Diseases Of Wheat, Collins Bugingo Jan 2018

Efficacy Of Seed Treatments, Microbial And Biochemical Pesticides For Managing Early Tan Spot And Stripe Rust Diseases Of Wheat, Collins Bugingo

Electronic Theses and Dissertations

Wheat is a major cereal crop in the U.S.A and in the world. However, its production is hampered by a number of factors both biotic and abiotic. Foliar diseases like tan spot caused by Pyrenophora tritici-repentis and stripe rust caused by Puccinia striiformis f. sp. tritici, are economically important diseases causing over 5-55 % yield loss. To assess the efficacy of fungicide seed treatments in the management of early tan spot, two hard red spring wheat cultivars “Select” and “Brick” were treated with seedapplied commercially available combo fungicides metalaxyl + pyraclostrobin + triticonazole and difenoconazole + mefenoxam + sedaxane …