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Monitoring Soft-Mast Production In Pine Woodland Restoration Areas On The Ouachita National Forest, Tamara B. Wood Dec 2017

Monitoring Soft-Mast Production In Pine Woodland Restoration Areas On The Ouachita National Forest, Tamara B. Wood

Electronic Theses and Dissertations

The use of prescribed fire is integral to the restoration of open woodland habitats in the southeast, including shortleaf pine (Pinus echinata) woodlands in the Ouachita Mountains. Mature pine habitats maintained with recurrent disturbances have an open understory with a rich floristic diversity that provides quality habitat for many wildlife species, including the endemic and endangered red-cockaded woodpecker (Picoides borealis). Fire has many potential benefits for wildlife; however, the effects of fire on several important woody soft-mast producing species are not fully understood. Soft-mast quantity and quality is a key component in determining year-round habitat quality …


Evaluating Mine Soil Prepared By Scraper Pans For Herbaceous Plants And Pine Seedlings At An East Texas Lignite Surface Mine, Hannah Z. Angel Aug 2017

Evaluating Mine Soil Prepared By Scraper Pans For Herbaceous Plants And Pine Seedlings At An East Texas Lignite Surface Mine, Hannah Z. Angel

Electronic Theses and Dissertations

Since 1974, Luminant Mining Company, LLC (Luminant) has planted over 38.7 million trees on its reclaimed lignite surface mine operations in Texas. For decades, the use of improved reclamation techniques on Luminant’s mined lands have resulted in over 31,160 ha reclaimed to forests, wildlife habitat, and pastures with productivity levels similar to those found on unmined lands. The development of new reclamation methodologies offers opportunities to further improve productivity of planted trees at Luminant’s Martin Lake Oak Hill Mine in east Texas. The conventional haulback or ‘truck shovel’ reclamation method uses haul trucks for the selective transport and placement of …


Pinching And Spacing Effects On Cut Sunflower (Helianthus Annuus) Production In East Texas, Rebecca B. Burnett Aug 2017

Pinching And Spacing Effects On Cut Sunflower (Helianthus Annuus) Production In East Texas, Rebecca B. Burnett

Electronic Theses and Dissertations

Three experiments evaluated pinching and spacing on Helianthus annuus in East Texas to determine their effects on growth and development. Experiment 1 was designed to determine the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold’ sunflowers. Results from experiment 1 showed non-pinched plants produced marketable stem lengths and flower sizes, while pinched plants’ stem length, stem diameter, flower diameter, and disk diameter decreased compared to the non-pinched plants. The objective for experiment 2 was to evaluate pinching and spacing treatments on ‘Pro Cut Gold’ sunflowers. All spacings for non-pinched plants in experiment 2 produced marketable …


Cultivar, Season Extension, Fertilizer Trials Of Swiss Chard And Pedagogy Of Assessing Cultivars Using Technology, Chanelle Angeny Aug 2017

Cultivar, Season Extension, Fertilizer Trials Of Swiss Chard And Pedagogy Of Assessing Cultivars Using Technology, Chanelle Angeny

Electronic Theses and Dissertations

Abstract. Diversity of species is a cornerstone of horticulture, and the constant stream of new plant cultivars broadens the palette of options available to the industry. Fifteen Swiss chard (Beta vulgaris var. cicla) cultivars were evaluated during the fall/winter of 2014-2015 season (season 1) and 27 cultivars during the fall/winter of 2015-2016 season (season 2) to determine the best performing cultivars for production and landscape use for east Texas and the southeast by assessing survivability and yield. There was an increase in production of 3.0 ± 0.5 g per plant per harvest under the low tunnel. The cultivar …


Advancing Development Of Porphyra Umbilicalis As A Red Algal Model System And Aquaculture Crop, Charlotte Royer May 2017

Advancing Development Of Porphyra Umbilicalis As A Red Algal Model System And Aquaculture Crop, Charlotte Royer

Electronic Theses and Dissertations

The marine red alga Porphyra umbilicalis (Rhodophyta, Bangiaceae) has ideal traits to allow it to become a model organism, including its economic value, reproduction in the northwestern Atlantic through asexual neutral spores (NS), and availability of fully-sequenced nuclear and organelle genomes. Research on the bacterial component of the Porphyra microbiome is ongoing. To advance model organism development and support microbial studies, data on natural reproductive trends and early embryonic development are needed, along with a system for genetic transformation, and ways of visualizing the attached microbial community. To meet these needs, two years of phenological data were analyzed, revealing seasonal …


Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett May 2017

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …


Perimeter Cropping As A Means Of Reducing Insect Injury And Increasing Crop Yield, Brett L. Owens Jan 2017

Perimeter Cropping As A Means Of Reducing Insect Injury And Increasing Crop Yield, Brett L. Owens

Electronic Theses and Dissertations

The squash vine borer, Melittia cucurbitae Harris, (Lepidoptera: Sesiidae) is a destructive insect known to injure a broad range of cucurbit crops. Many studies have focused on insecticide management of this insect in squash (Cucurbita) and pumpkin (Cucurbita pepo Linnaeus) production; however, little work has been documented on organic approaches to reduce or eliminate injury from this pest to these crops in the Midwest. This study used trap cropping and pollinator mixtures to test whether a reduction of squash vine borer could be achieved in a specific cultivar of pumpkins, Cucurbita pepo ‘Howden’. The study was …


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 …


Impacts Of Landscape Position And Nitrogen Fertilizer On Soils, Carbon And Nitrogen Leaching, And Greenhouse Gas Fluxes From Switchgrass Production In South Dakota, Liming Lai Jan 2017

Impacts Of Landscape Position And Nitrogen Fertilizer On Soils, Carbon And Nitrogen Leaching, And Greenhouse Gas Fluxes From Switchgrass Production In South Dakota, Liming Lai

Electronic Theses and Dissertations

Switchgrass (Panicum virgatum L.) production for biofuels has potential economic values. It can also improve soil properties and perform better under marginal lands than the other major biomass crops. However, little is known about its potential ecological impacts assessed in terms of soils, water, and air quality in the northern Great Plains region of United States of America. The objectives of this study were to (i) evaluate the impacts of nitrogen fertilization rate (N rate) and landscape position on soil pH, soil organic carbon (SOC), total nitrogen (TN), bulk density (ρb), and phosphorus (P) in switchgrass field; (ii) assess …


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 …


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 …


Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne Jan 2017

Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne

Electronic Theses and Dissertations

The adoption of regenerative farming practices is gaining traction, but the costs and benefits are not often considered on a systems level. Encouraging biodiversity and soil health is the goal of many agricultural practices used in regenerative farming; regenerative systems employ practices which abide by the two main principles of increasing biodiversity and decreasing disturbance, with the goal of encouraging ecosystem functioning to minimize inputs and maximize the productivity of a farm. I examined the management of corn (Zea mays) fields across four states in the Upper Midwest region of the United States. Regenerative systems in this study …


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 …


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 …


Soil Response To Cropping Sequences And Grazing Under Integrated Crop-Livestock System, Hanxiao Feng Jan 2017

Soil Response To Cropping Sequences And Grazing Under Integrated Crop-Livestock System, Hanxiao Feng

Electronic Theses and Dissertations

Integrated crop-livestock system (ICLS) is helpful in diversifying a farm for improving its long-term sustainability and economic benefits. In the United States, the ICLS has been increasing in recent years because of its economic and environmental benefits. However, the impacts of ICLS on soil quality is not well documented in North Dakota. The objective of our study is to assess the impacts of cropping sequences and cattle grazing on the selected soil properties in the crop diversity and livestock integration practice. This study site was established in 2010 at the Dickinson Research Extension Center, Dickinson, North Dakota. The study design …


Development Of Best Management Practices For Production Of Ethiopian Mustard (Brassica Carinata) In South Dakota, Phillip Kenneth Alberti Jan 2017

Development Of Best Management Practices For Production Of Ethiopian Mustard (Brassica Carinata) In South Dakota, Phillip Kenneth Alberti

Electronic Theses and Dissertations

Ethiopian mustard (Brassica carinata) is an alternative non-food oilseed crop which has received interest for its potential as a low-input option for production in the Northern Great Plains (NGP). As B. carinata is a new crop to the NGP, the best management practices have yet to be developed. The overall goal of this project was to develop best management practices for B. carinata production in two diverse agroenvironments in South Dakota. Two field experiments were conducted to assess the response of two B. carinata varieties to i) four seeding rates (4.5, 9, 13.5, and 18 kg ha-1 …


Improvement Of Milling And Nutritional Quality Characteristics Of Oats Through Genomic Selection, Sudha Neupane Adhikari Jan 2017

Improvement Of Milling And Nutritional Quality Characteristics Of Oats Through Genomic Selection, Sudha Neupane Adhikari

Electronic Theses and Dissertations

Oats can lower cholesterol, reduce risks of type-2 diabetes, and help prevent heart diseases when consumed daily. Therefore, it is important to evaluate and select breeding lines with desirable milling and nutritional quality traits. Genomic selection, which uses genotyping data to predict the breeding value of an individual, is a promising method to increase genetic gain by selecting for quality traits earlier in the line development process. In this study, we collected phenotypic data for three nutritional traits (protein, β- glucan, and fat content) and five milling quality traits (percent plumps, percent thins, percent plump groat, groat percent and thousand …


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 …


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 …


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 …


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 …


Assessment Of Hard Red Spring Wheat Germplasm For Cold Temperature Germination Tolerance, Ulas Cinar Jan 2017

Assessment Of Hard Red Spring Wheat Germplasm For Cold Temperature Germination Tolerance, Ulas Cinar

Electronic Theses and Dissertations

When planted early in the season, hard red spring wheat (HRSW; Triticum aestivum L.) can help for both vegetative growth and yield providing maximum agronomic productivity. The north-central Great Plains growing region is considered best for developing varieties that germinate in sub-optimal temperatures. Within limited regions, spring wheat planting typically occurs between mid-April and late May, when soil temperatures are 8 °C to 14 °C. Early season planting may result in freezing stress, while late season planting can result in heat and drought stress. Our study tested the germination rate of hard red spring wheat (HRSW) over a range of …


Regulation Of Arf16-2 By Microrna160 During Soybean Root Nodule Development, Spencer Schreier Jan 2017

Regulation Of Arf16-2 By Microrna160 During Soybean Root Nodule Development, Spencer Schreier

Electronic Theses and Dissertations

Soybean is an excellent candidate for sustainable agriculture due to its production of nutritious, versatile beans and the ability to form symbiotic organs called root nodules that perform nitrogen fixation. As demand for both yield and sustainable agriculture continue to increase, root nodules offer an attractive alternative to expensive and environmentally harmful nitrogen fertilizers. Understanding root nodule formation may open genetic engineering avenues for optimizing nitrogen fixation performance and transferring the nodule-formation ability to other plants. A major determinant of nodule numbers and quality in soybean is microRNA 160 (miR160), which dictates developmental stage-specific auxin sensitivity by targeting repressor auxin …


Impacts Of Integrated Crop-Livestock System On Soil Surface Greenhouse Gas Fluxes At A Farm Scale In South Dakota, Brant Douville Jan 2017

Impacts Of Integrated Crop-Livestock System On Soil Surface Greenhouse Gas Fluxes At A Farm Scale In South Dakota, Brant Douville

Electronic Theses and Dissertations

Grazing and cover crops (CC) can impact soil nutrient cycling but may increase the greenhouse gas (GHG) emissions from soils. However, little is known about their impacts on soil properties and soil surface GHG emissions in an integrated crop-livestock system (ICLS) in South Dakota, USA. The present study was conducted at a farm scale at the Research Farm of South Dakota State University, Brookings, South Dakota, to assess the impact of cover crops and grazing on soil pH, electrical conductivity (EC), and bulk density (BD), and soil surface carbon dioxide (CO2), methane (CH4), and nitrous oxide …


Molecular Characterization Of Spot Blotch And Bacterial Leaf Streak Resistance In Bread Wheat, Girma Ayana Jan 2017

Molecular Characterization Of Spot Blotch And Bacterial Leaf Streak Resistance In Bread Wheat, Girma Ayana

Electronic Theses and Dissertations

Spot blotch (SB), caused by Bipolaris sorokiniana (Sacc.) Shoem, and bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa (Smith et al.), two important foliar diseases of wheat in the major production regions of the US and the world. Deployment of adequate host resistance against them depends on determining the resistance genes or quantitative trait loci (QTLs) responsible for the trait and identification of genetic markers linked to QTL that facilitate markers assisted breeding. We conducted two independent studies and characterized QTLs for BLS and SB resistance. In the first study, we constructed a genetic linkage map of 1,211 …


Effects Of Root Isoflavonoids And Hairy Root Transformation On The Soybean Rhizosphere Bacterial Community Structure, Laura White Jan 2017

Effects Of Root Isoflavonoids And Hairy Root Transformation On The Soybean Rhizosphere Bacterial Community Structure, Laura White

Electronic Theses and Dissertations

Rhizodeposits play a key role in shaping rhizosphere microbial communities. In soybean, isoflavonoids are a key rhizodeposit component that aid in plant defense and enable symbiotic associations with rhizobia. However, it is uncertain if and how they influence rhizosphere microbial communities. Isoflavonoid biosynthesis was silenced via RNA interference of isoflavone synthase in soybean hairy root composite plants. Successive sonication was implemented to isolate soil fractions from 3 different rhizosphere zones at 1 and 3 weeks post planting. PCR amplicons from 16S rRNA gene variable regions V1- V3 and V3-V5 from these soil fractions were analyzed via denaturing gradient gel electrophoresis …


Mitigating Risks Of Ochratoxin A Contamination In Oats, Bandana Dhungana Jan 2017

Mitigating Risks Of Ochratoxin A Contamination In Oats, Bandana Dhungana

Electronic Theses and Dissertations

Ochratoxin A (OTA) is a toxic metabolite produced by several species of fungal genera Penicillium and Aspergillus. The major OTA producer in temperate regions (i.e. U.S., Canada, Europe) is Penicillium verrucosum. Oat (Avena sativa), like any other cereal grain, can be contaminated with OTA when storage conditions are favorable for fungal growth. The presence of OTA exceeding the European Union maximum limit of 3 ppb in processed food has been reported in some samples of oat-based breakfast cereals from the US. The use of oat genotypes with limited OTA accumulation would be an effective way to …


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 …


Characterization Of Pyrenophora Tritici-Repentis In Wheat And Rye To Study Tan Spot Susceptibility And Insights Into Its Relationship With Stem Rust Resistance, Sidrat Abdullah Jan 2017

Characterization Of Pyrenophora Tritici-Repentis In Wheat And Rye To Study Tan Spot Susceptibility And Insights Into Its Relationship With Stem Rust Resistance, Sidrat Abdullah

Electronic Theses and Dissertations

Tan spot, caused by the ascomycete fungus, Pyrenophora tritici-repentis (Ptr), is a major foliar fungal disease of wheat worldwide. To date, Ptr isolates have been grouped into eight races based on the production of three host selective effectors (toxins), Ptr ToxA, ToxB, and ToxC, which are associated with necrosis and chlorosis symptoms on wheat differential lines. In order to see the correlation between stem rust resistance and tan spot susceptibility in 1970’s, to know the pathogen virulence profile, and explore the sources of tan spot resistance, we recovered isolates from wheat and rye and evaluated wheat and rye lines with …