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Effects Of Phase Feeding During Gestation On Gilt Performance, Offspring Quality And Robustness, Agatha Ampaire Jan 2017

Effects Of Phase Feeding During Gestation On Gilt Performance, Offspring Quality And Robustness, Agatha Ampaire

Electronic Theses and Dissertations

A total of 51 gilts in 6 blocks were randomly assigned to one of 3 feeding regimens: Constant (Constant-f), 2.21 kg/d of a standard diet from breeding to d 112 of gestation (1.7 g Lys/kcal ME; 3276 kcal ME/kg); Bump feeding (Bump-f), the standard diet at 2.21 kg/d from breeding to d 89 and 2.61 kg/d from d 90 - 112; Phase feeding (Phase-f ), 2.21 kg/d from breeding to d 89 (1.5 g Lys/kcal ME; 3275 kcal ME/kg) and 2.61 kg/d from d 90 - 112 (2.1 g Lys/Kcal ME; 3290 Kcal ME/kg) over 2 reproductive cycles. Sows received …


Diaporthe, Soybean Cyst Nematode, And Soybean Aphid: An Evaluation Of Potential Interactions Occurring Among Pests On Soybean In South Dakota, John Philip Posch Jan 2017

Diaporthe, Soybean Cyst Nematode, And Soybean Aphid: An Evaluation Of Potential Interactions Occurring Among Pests On Soybean In South Dakota, John Philip Posch

Electronic Theses and Dissertations

Soybean Glycine max (L.) Merr., is an important crop grown in South Dakota, with an estimated production of $2.33 billion in 2015. However, soybean production in South Dakota is compromised by four pests, the fungal pathogens Diaporthe longicolla (Hobbs) Santos, Vrandecic, and Phillips and Diaporthe caulivora (Athow and Caldwell) Santos, Vrandecic, and Phillips, the soybean cyst nematode Heterodera glycines Ichinohe (SCN), and the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae). Additionally, these pest can co-occur in fields within South Dakota and the implications associated with interactions among these pests are unknown. We hypothesized that both Diaporthe species would interact with …


Identification Of Physiological And Morphological Traits Governing High Water Use Efficiency In Alfalfa, Krishna Ghimire Jan 2017

Identification Of Physiological And Morphological Traits Governing High Water Use Efficiency In Alfalfa, Krishna Ghimire

Electronic Theses and Dissertations

Alfalfa is an important forage crop worldwide. Being deep-rooted, N2-fixing and high yielding, alfalfa has great economic, ecological and nutritional benefits. While alfalfa is a high yielding crop, its high productivity depends on irrigation water in many areas and consumes the greatest amount of water among all the major crops. With a growing demand for water resources due to an increase in human population and industrial water use, plus frequent drought due to climate change, irrigation water has become increasingly scarce and expensive. To sustain high production of alfalfa with limited water resource, alfalfa cultivars with improved water use efficiency …


Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens Jan 2017

Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens

Electronic Theses and Dissertations

Phenotypic plasticity, the ability of an individual to alter its growth in response to environmental conditions, is an attribute that is considered a likely invader attribute, as it provides the opportunity to expand its ecological niche breadth. Adaptive phenotypic plasticity can affect not only the ability to establish in a new environment, but also the ability to outperform the existing vegetation over time. Bromus inermis (smooth brome) and Poa pratensis (Kentucky bluegrass) are invasive species in tall- and mixed-grass prairie ecosystems. The objectives of this two-part study were to quantify the adaptive plasticity of biomass accumulation and tiller production in …


Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid Jan 2017

Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid

Electronic Theses and Dissertations

Diverse cropping systems and no-till (NT) are beneficial in improving soil organic carbon (SOC) and other soils properties. The present study was conducted to evaluate the interactions and impacts of long-term tillage and diverse crop rotation systems on soil quality indicators that include a range of soil chemical, physical, hydrological, and microbial properties. The study was established in 1991 at Beresford, South Dakota and included three crop rotation systems [2-yr; maize (Zea mays L.)-soybean (Glycine max L.), 3-yr; maize-soybean-oat (Avena sativa L.), and 4-yr; maize-soybean-oat-wheat (Triticum aestivum L.)] managed under two tillage systems (NT and CT; conventional- tillage). Soil sampling …


Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel Jan 2017

Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel

Electronic Theses and Dissertations

From 2015-2017, we evaluated a newly established bighorn sheep (Ovis canadensis) herd in the Deadwood Region of the Black Hills, South Dakota. Our objectives were to 1a) determine annual survival rates, 1b) determine cause-specific mortality, 1c) estimate population size, 2a) assess genetic diversity, 2b) assess disease prevalence, 3) evaluate movement patterns post-release, 4a) evaluate 3rd-order habitat selection, and 4b) estimate herbaceous biomass at foraging sites post-release of translocated bighorn sheep. In February 2015, we captured and translocated 26 bighorn sheep from the Luscar Mine near Hinton, Alberta, Canada to the Deadwood Region of the Black Hills, South Dakota. Overall annual …


Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez Jan 2017

Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez

Electronic Theses and Dissertations

Irrigation water is scarce. Hence, accurate estimation of crop water use is necessary for proper irrigation managements and water conservation. Satellite-based remote sensing is a tool that can estimate crop water use efficiently. Several models have been developed to estimate crop water requirement or actual evapotranspiration (ETa) using remote sensing. One of them is the Mapping EvapoTranspiration at High Resolution using Internalized Calibration (METRIC) model. This model has been compared with other methods for ET estimations including weighing lysimeters, pan evaporation, Bowen Ratio Energy Balance System (BREBS), Eddy Covariance (EC), and sap flow. However, comparison of METRIC model outputs to …


Macropinosome Maturation Is A Clathrin Dependent Process In Bone Marrow Macrophages, Susmita Poudel Jan 2017

Macropinosome Maturation Is A Clathrin Dependent Process In Bone Marrow Macrophages, Susmita Poudel

Electronic Theses and Dissertations

Macrophages nonspecifically take up extracellular fluids, solutes and macromolecules by macropinocytosis. Understanding the mechanisms of macropinosome maturation will inform the study of lipid uptake, viral entry, antigen processing and presentation, as well as regulation of cell growth. Colony stimulating factor-1 receptor (CSF-1R) is internalized by small vesicle endocytosis, trafficked to nascent macropinosomes and degraded. These CSF-1R positive macropinosomes mature through a sequence similar to endosomes, progressing from EEA1 and Rab5 to Rab7 positive vesicles before fusing with lysosomes. Here we report the assembly of clathrin on internalized macropinosomes shown both by live-cell microscopy of cells expressing clathrin light chain-yellow fluorescent …


Studying Microflora Of Semi-Hard Cheese, And Sporulation Within Contact Surface Biofilms, Dalia Khan Jan 2017

Studying Microflora Of Semi-Hard Cheese, And Sporulation Within Contact Surface Biofilms, Dalia Khan

Electronic Theses and Dissertations

The first study was conducted on commercial Italian semi-hard cheese samples that were analyzed microbiologically to understand the effect of fast and slow rate of cooling on cheese microflora during ripening process at different temperatures. A cheese plant noticed an active growth of non-starter lactic acid bacteria, especially the heterofermentative bacteria, in ripened cheese blocks, which weren’t fully cooled. For that, three cheese sample sets, each having 8 samples, were received from the cheese plant for microbiological analysis. The first set included a group of fast cooled cheese samples to 38°F, and the other group was slow cooled to 50°F. …


Mountain Lion (Puma Concolor) Population Characteristics And Resource Selection In The North Dakota Badlands, Randy D. Johnson Jan 2017

Mountain Lion (Puma Concolor) Population Characteristics And Resource Selection In The North Dakota Badlands, Randy D. Johnson

Electronic Theses and Dissertations

Mountain lions (Puma concolor) have significant ecological impacts on the ecosystems they inhabit, leading to both biological and social ramifications. Yet, due to the relatively recent natural recolonization by mountain lions of the Little Missouri Badlands Region of western North Dakota, detailed data regarding many aspects of this population have been lacking. Therefore, we studied mountain lions occupying the Badlands Region to improve our understanding of mountain lion population ecology, resource selection, and occurrence in North Dakota. Our objectives were to: 1) improve the accuracy of home range size, subadult movement, and survival estimates of mountain lions in …


Impacts Of Crop Residue And Cover Crops On Soil Hydrological Properties, Soil Water Storage And Water Use Efficiency Of Soybean Crop, Kopila Subedi-Chalise Jan 2017

Impacts Of Crop Residue And Cover Crops On Soil Hydrological Properties, Soil Water Storage And Water Use Efficiency Of Soybean Crop, Kopila Subedi-Chalise

Electronic Theses and Dissertations

Cover crops and crop residue play a multifunctional role in improving soil hydrological properties, soil water storage and water use efficiency (WUE). This study was conducted to better understand the role of crop residue and cover crop on soil properties and soil water dynamics. The study was conducted at the USDA-ARS North Central Agricultural Research Laboratory, located in Brookings, South Dakota. Two residue removal treatments that include low residue removal (LRR) and high residue removal (HRR) were established in 2000 with randomized complete block design under no-till corn (Zea mays L.) and soybean (Glycine max L.) rotation. In 2005, cover …


Cardiovascular Risk, Remote Ischemic Postconditioning, And Endothelial Ischemia-Reperfusion Injury, Brian A. Hemenway Jan 2017

Cardiovascular Risk, Remote Ischemic Postconditioning, And Endothelial Ischemia-Reperfusion Injury, Brian A. Hemenway

Electronic Theses and Dissertations

Remote ischemic postconditioning (rIpost) is a potent vasculoprotective stimulus that is thought to reduce reperfusion injury associated with heart disease. However, certain animal models of cardiometabolic risk factors such as dyslipidemia, diabetes, and hypertension suggest the beneficial effects of rIpost to lessen reperfusion injury may be diminished. These findings have not been studied in clinically relevant humans. The aim of this study was to determine whether the protective effects of rIpost are reduced in the context of raised cardiometabolic risk in humans. Seven participants with raised cardiometabolic risk burden (age:57±7 years; BMI: 31±4kgm2participated in this 2X2 randomized cross-over …


Native Species For Biomass Production And Roadside Habitat In South Dakota, Jacob Foley Jan 2017

Native Species For Biomass Production And Roadside Habitat In South Dakota, Jacob Foley

Electronic Theses and Dissertations

Native grasses and forbs are being considered for planting along South Dakota roadsides to create a favorable habitat for wildlife while also allowing landowners a source of forage and biomass production. South Dakota is host to 54,900 hectares (145,000 acres) of right-of-way that are managed by the South Dakota Department of Transportation. Approximately 80% of the roadsides are used by landowners for hay production. Species diversity and potential biomass yield were determined for the current roadside vegetation along four transects (SD Highways 14, 34 and 50) and SD I- 29 between White, SD and Elk Point, SD. Smooth bromegrass (Bromus …


Improving Survey Methodology To Monitor Rare Grassland Birds In South Dakota, Kassondra Hendricks Jan 2017

Improving Survey Methodology To Monitor Rare Grassland Birds In South Dakota, Kassondra Hendricks

Electronic Theses and Dissertations

Breeding Bird Survey (BBS) data for grassland bird species has shown the most rapid population decline of any other bird group. Current roadside survey techniques, however, may fall short of providing accurate numbers of rare grassland bird species such as chestnut-collared longspur (Calcarius ornatus), lark bunting (Calamospiza melanocorys), Sprague’s pipit (Anthus spragueii), and Baird’s sparrow (Ammodramus bairdii). Trends resulting from roadside data for grassland birds are oftentimes determined to be statistically insignificant because many grassland bird species occur on too few routes, occur in low numbers per route, and show high annual fluctuations in number. It is possible roadside surveys …


Investigation Of Candidate Loci Associated With Maize Perennialism, Anjun Ma Jan 2017

Investigation Of Candidate Loci Associated With Maize Perennialism, Anjun Ma

Electronic Theses and Dissertations

Developing perennial grain crops is an effective and crucial way to prevent soil erosion caused by conventional agriculture of using annual crops while meeting the increasing need of global food demand. We hypothesized that the regrowth in Zea might be controlled by two dominant complementary genes. F1 hybrids were created by crossing Zea diploperennis Iltis, Doebley & R. Guzman with annual Zea mays L. ssp. mays inbred line B73. A Total of 134 F2 plants derived from nine F1 were planted and phenotyped. A subpopulation of 94 F2 plants were genotyped with Genotype-by- Sequencing (GBS) and called 10,431 SNPs after …


Swift Foxes In Southwestern South Dakota: Assessing The Current Status Of A Reintroduced Population, Sarah Ann Nevison Jan 2017

Swift Foxes In Southwestern South Dakota: Assessing The Current Status Of A Reintroduced Population, Sarah Ann Nevison

Electronic Theses and Dissertations

Swift foxes (Vulpes velox) were reintroduced into Badlands National Park between 2003 and 2006 after being nearly extirpated from South Dakota in the early 1900’s. Genetic analysis provided strong evidence that the reintroduction was successful, but viability analysis indicated the population may be in jeopardy with a high probability of extinction. Recently, the population has declined due to various biotic and abiotic factors (e.g., recent weather patterns, effects of plague [Yersinia pestis], and increased coyote [Canis latrans] numbers). No information on the status of swift foxes has been collected since 2009. Between 2014 and 2016, the objectives of this study …


Using Gluten Index To Improve Spring Wheat Loaf Volume Prediction, Yaming Lu Jan 2017

Using Gluten Index To Improve Spring Wheat Loaf Volume Prediction, Yaming Lu

Electronic Theses and Dissertations

Wheat (Triticum aestivum L.) is the most widely cultivated crop in the world and contributes about 20% of the total dietary calories and proteins globally. Unique properties of doughs formed from wheat flour make it feasible to produce a range of food, including bread. Loaf volume is the most perceptible indicator for breadmaking quality. Selection in the early generations for loaf volume is difficult due to the requirement of the large volume of grains and due to the costly, time-consuming, and labor-intensive evaluation process. Identification of simple and reliable predictive tests for loaf volume is highly desirable. This study …


Biofilm Formation By Common Dairy Sporeformers On Native And Modified Stainless Steel Surfaces, Shivali Jindal Jan 2017

Biofilm Formation By Common Dairy Sporeformers On Native And Modified Stainless Steel Surfaces, Shivali Jindal

Electronic Theses and Dissertations

Aerobic sporeformers can be traced in a variety of dairy products such as milk powders, evaporated milk, and canned products, which demonstrates their capability of resisting high temperature treatments such as pasteurization and Ultra high temperatures. These bacilli also actively attach to the stainless steel surfaces, consequently resulting in the formation of biofilms. Product quality as well as its safety is undesirably affected by the growth of these sporeforming bacteria. Therefore, creating an ideal environment for the processing of dairy products is a critical challenge for the dairy industry. Hence, the objective of this research was to analyze various surface …


Factors Affecting Feedlots' Decisions On Cattle Marketing Options: A National Study, Charlotte Owusu-Smart Jan 2017

Factors Affecting Feedlots' Decisions On Cattle Marketing Options: A National Study, Charlotte Owusu-Smart

Electronic Theses and Dissertations

This thesis investigates the economic implication of changing slaughter volume patterns across the cash and contract markets in the US cattle industry. Weekly time series data that spans from November 2002 to December 2015 was used in the analysis. Empirical evidence suggests that Mandatory Price Reporting (MPR) played an important role in changing slaughter volumes across the cash and contract markets. Additionally, price of feeder cattle, cattle quality characteristics (Choice-Select spread and the percentage of animals grading choice or better) among others influence feedlots’ decision to use a particular marketing arrangement.


Senecavirus A: Epidemiology, Pathogenesis And Infection Dynamics, Lok Raj Joshi Jan 2017

Senecavirus A: Epidemiology, Pathogenesis And Infection Dynamics, Lok Raj Joshi

Electronic Theses and Dissertations

Senecavirus A (SVA) is a positive sense single-stranded virus that belongs to the genus Senecavirus within the family Picornaviridae. Senecavirus has been present in US swine population since 1988. However, there have been only a few reports of SVA associated with disease in last two decades. In late 2014 early 2015, a sudden increase in the number of cases of Senecavirus A associated with vesicular disease was observed in Brazil, the US and China. Affected pigs presented vesicles on snout, coronary band, and dewclaw. Additionaly, increased neonatal mortality has been reported in the field. Many aspects of SVA epidemiology, …


Enhancing Cellulase Production Of Aureobasidium Pullulans For Use In Converting Dried Distillers’ Grains With Solubles Into A Higher Protein Feed, Emily L. Baldwin Jan 2017

Enhancing Cellulase Production Of Aureobasidium Pullulans For Use In Converting Dried Distillers’ Grains With Solubles Into A Higher Protein Feed, Emily L. Baldwin

Electronic Theses and Dissertations

Main limitations of dried distillers’ grains with solubles (DDGS) as meal for monogastric animals is the presence of high fiber content, reduced fat content, and poor amino acid balance. This causes a reduced economic value of DDGS for these species due to its low inclusion rates. The goal of this theses was to create new strains of a fungus, Aureobasidium pullulans, with enhanced cellulase production and use it to optimize an enzymatic saccharification, pretreatment, and fungal conversion process to enhance the nutritional value of DDGS. Various combinations of enzymatic saccharification, physical/chemical pretreatments, and mutant strains of fungi were investigated …


Measuring Aquatic Organism Responses To Grassland Restoration: Does The Field Of Dreams Really Exist?, David A. Schumann Jan 2017

Measuring Aquatic Organism Responses To Grassland Restoration: Does The Field Of Dreams Really Exist?, David A. Schumann

Electronic Theses and Dissertations

Landscape homogenization and the degradation of riparian areas has greatly impaired stream ecosystems throughout North America. Conservation programs may repair riparian ecosystems to indirectly improve water quality and instream habitat heterogeneity in hopes to elicit biological responses. However, focused manipulations on isolated stream fragments have rarely achieved biological goals. Prairie streams with restored riparian areas were appraised (chemical, physical, and biological variables) to quantify the indirect effects of prevalent grassland conservation practices on aquatic resources. Riparian rehabilitation, via passive methods, promoted bank-stabilizing vegetation along all conservation stream reaches. Riparian vegetation and function quickly recovered from previous agricultural disturbances at conservation …


Performance Of The Producer Accumulator In Corn And Soybean Commodity Markets, Chad Te Slaa Jan 2017

Performance Of The Producer Accumulator In Corn And Soybean Commodity Markets, Chad Te Slaa

Electronic Theses and Dissertations

This research quantifies risk reduction and performance of the producer accumulator contract in corn and soybean markets. To quantify performance, we use three alternative theoretical pricing models to estimate historical producer accumulator contract specifications in corn and soybean markets. We then compare the performance of the producer accumulator to eight alternative agricultural marketing strategy portfolios that are also used in new generation grain contracts. The performance measures we compare are: average bushel price that would be received by the producer, daily portfolio risk, and the Sharpe ratio. The period we examine performance was between 2008 and 2017. We investigate performance …


A Survey Of Non-Crop Plants As Alternative Hosts To Raspberries For Drosophila Suzukii (Spotted Wing Drosophila), Bennur Agbaba Jan 2017

A Survey Of Non-Crop Plants As Alternative Hosts To Raspberries For Drosophila Suzukii (Spotted Wing Drosophila), Bennur Agbaba

Electronic Theses and Dissertations

The spotted wing fruit fly (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is a pest of small fruit crops. Unlike most other Drosophila species, this insect can oviposit into ripe fruits, rendering them unmarketable. Drosophila suzukii is spreading quickly throughout the continental United States including South Dakota, and causing serious damage to horticultural crops, particularly those within the fruit industry. This study determines the D. suzukii host plant both commercial crops and native plants, and defines non-crop host plants by season in South Dakota. Further, it confirms the occurrence of the fly in southeastern South Dakota and identifies high-risk infestation areas …


Differential Gene Expression In Two Nodule Zones Of Soybean, Sunita Pathak Jan 2017

Differential Gene Expression In Two Nodule Zones Of Soybean, Sunita Pathak

Electronic Theses and Dissertations

Soybean, a leguminous plant and rhizobia establishes symbiotic relationships, forming root nodules. Nodule organogenesis starts with cortical cell division forming infection and parenchyma zones which houses N-fixing bacteria and block O2 for nitrogenase enzyme function, respectively. The mechanism by which root cortical cells give rise to two structurally and functionally different nodule tissues is not known. One approach to address this knowledge gap is to evaluate global gene expression patterns in these two tissue types during nodule development. Using INTACT method, we developed two promoters, ENOD2 (nodule parenchyma) and ENOD40 (infection zone) driven nuclear envelope biotin tagging constructs and isolated …


Phylogenetic And Associated Phenotypic Analysis Of Salmonella Enterica Serovar Mbandaka, Linto Antony Jan 2017

Phylogenetic And Associated Phenotypic Analysis Of Salmonella Enterica Serovar Mbandaka, Linto Antony

Electronic Theses and Dissertations

Food borne salmonellosis is a global public health concern caused by Salmonella, that causes enteric disease both in humans and animals. Most of the pathogenic Salmonella serovars fall under Salmonella enterica subspecies enterica, a major subspecies group that includes more than 50% of total identified Salmonella serovars. New serovars are identified each year and overall incidence of salmonellosis may mask the outbreak incidences caused by individual serovars. Infrequently reported serovar outbreaks can be a significant threat to public health. Salmonella enterica serovar Mbandaka is one of the infrequently reported causative agents of non-typhoidal salmonellosis in USA. But it …


Surveillance Of Emerging Livestock Viruses, Faten A. Okda Jan 2017

Surveillance Of Emerging Livestock Viruses, Faten A. Okda

Electronic Theses and Dissertations

Accurate and rapid diagnostic tests are essential for the management and control of emerging infectious diseases. Therefore, the overall goals of studies presented in this dissertation were to provide improved diagnostic and surveillance capabilities for several emerging viral diseases impacting the livestock industry and to provide insight into appropriate control strategies. Recent, severe outbreaks of porcine epidemic diarrhea virus (PEDV) in Asia and North America highlighted the need for well-validated diagnostic tests for identification of PEDV infected animals and evaluation of their immune status. PEDV was first detected in the U.S. in May 2013 and another swine coronavirus, porcine deltacoronavirus …


Design, Synthesis And Biological Screening Of Novel Cucsinspired Estrone Analogues Towards Treatment Of Hepatocellular Carcinoma, Mater Hussen Mahnashi Jan 2017

Design, Synthesis And Biological Screening Of Novel Cucsinspired Estrone Analogues Towards Treatment Of Hepatocellular Carcinoma, Mater Hussen Mahnashi

Electronic Theses and Dissertations

Cucurbitacins (CUCS) are natural products with highly oxygenated tetracyclic triterpenes produced mostly by Cucurbitaceae family plant. They are known for their therapeutic efficiency with different biological activities, such as anti-inflammatory, hepatoprotective and anti-cancer. Hepatocellular carcinoma (HCC) is the third leading cause of death worldwide. Previous reports have shown the ability of CUCS to inhibit the growth of hepatocellular carcinoma cell lines (HepG-2) significantly. Structural activity relationship studies suggested the potential of the 23, 24 enone side chain of CUCS to bind to the Epidermal Growth Factor Receptor (EGFR). Due to the limited quantities of CUCS upon isolation and the challenges …


Managing Phomopsis Stem Canker Of Sunflower Using Improved Diagnosis And Quantification Of The Causal Pathogens, Taylor Rae Olson Jan 2017

Managing Phomopsis Stem Canker Of Sunflower Using Improved Diagnosis And Quantification Of The Causal Pathogens, Taylor Rae Olson

Electronic Theses and Dissertations

Phomopsis stem canker is a disease that severely affects sunflower (Helianthus annuus) in the United States. From 2001 to 2015, disease prevalence has increased from 1.5% to 61%, and two new causal agents, Diaporthe gulyae and Diaporthe stewartii, have been described along with Diaporthe helianthi, which was always regarded as the main causal pathogen of the disease. At this time, options to manage the disease are limited. Currently, no commercial sunflower hybrids have resistance to all three species of Diaporthe, and no fungicides are labeled for control of Phomopsis stem canker of sunflower in the United …


Phytophthora Sojae Infecting Soybean: Pathotype Diversity, New Sources Of Resistance And Interaction With The Soybean Cyst Nematode, Rawnaq Nazneen Chowdhury Jan 2017

Phytophthora Sojae Infecting Soybean: Pathotype Diversity, New Sources Of Resistance And Interaction With The Soybean Cyst Nematode, Rawnaq Nazneen Chowdhury

Electronic Theses and Dissertations

Phytophthora root and stem rot, caused by Phytophthora sojae Kaufmann and Gerdemann, is an important disease of soybean (Glycine max L.) in South Dakota. To gain a better understanding of the importance of P. sojae in South Dakota, specifically pathotype diversity, identification of new resistance sources and the interaction with the soybean cyst nematode (Heterodera glycines Ichinohe, SCN), this research was undertaken with the following objectives - 1) to characterize the pathotype diversity of P. sojae causing Phytophthora root and stem rot on soybean in commercial fields in South Dakota; 2) to compare inoculation methods to evaluate for …