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Full-Text Articles in Life Sciences

Key Interplay Between The Co-Opted Sorting Nexin-Bar Proteins And Pi3p Phosphoinositide In The Formation Of The Tombusvirus Replicase, Zhike Feng, Nikolay Kovalev, Peter D. Nagy Dec 2020

Key Interplay Between The Co-Opted Sorting Nexin-Bar Proteins And Pi3p Phosphoinositide In The Formation Of The Tombusvirus Replicase, Zhike Feng, Nikolay Kovalev, Peter D. Nagy

Plant Pathology Faculty Publications

Positive-strand RNA viruses replicate in host cells by forming large viral replication organelles, which harbor numerous membrane-bound viral replicase complexes (VRCs). In spite of its essential role in viral replication, the biogenesis of the VRCs is not fully understood. The authors identified critical roles of cellular membrane-shaping proteins and PI(3)P (phosphatidylinositol 3-phosphate) phosphoinositide, a minor lipid with key functions in endosomal vesicle trafficking and autophagosome biogenesis, in VRC formation for tomato bushy stunt virus (TBSV). The authors show that TBSV co-opts the endosomal SNX-BAR (sorting nexin with Bin/Amphiphysin/Rvs- BAR domain) proteins, which bind to PI(3)P and have membrane-reshaping function during …


Role Reversal Of Functional Identity In Host Factors: Dissecting Features Affecting Pro-Viral Versus Antiviral Functions Of Cellular Dead-Box Helicases In Tombusvirus Replication, Cheng-Yu Wu, Peter D. Nagy Oct 2020

Role Reversal Of Functional Identity In Host Factors: Dissecting Features Affecting Pro-Viral Versus Antiviral Functions Of Cellular Dead-Box Helicases In Tombusvirus Replication, Cheng-Yu Wu, Peter D. Nagy

Plant Pathology Faculty Publications

Positive-stranded (+)RNA viruses greatly exploit host cells to support viral replication. However, unlike many other pathogens, (+)RNA viruses code for only a limited number of genes, making them highly dependent on numerous co-opted host factors for supporting viral replication and other viral processes during their infections. This excessive dependence on subverted host factors, however, renders (+)RNA viruses vulnerable to host restriction factors that could block virus replication. Interestingly, cellular ATP-dependent DEAD-box RNA helicases could promote or inhibit the replication of Tomato bushy stunt virus (TBSV) replication. However, it is currently unknown what features make a particular DEAD-box helicase either pro-viral …


Modeling The Relationship Between Estimated Fungicide Use And Disease-Associated Yield Losses Of Soybean In The United States I: Foliar Fungicides Vs Foliar Diseases, Ananda Y. Bandara, Dilooshi K. Weerasooriya, Shawn P. Conley, Carl A. Bradley, Tom W. Allen, Paul D. Esker Jun 2020

Modeling The Relationship Between Estimated Fungicide Use And Disease-Associated Yield Losses Of Soybean In The United States I: Foliar Fungicides Vs Foliar Diseases, Ananda Y. Bandara, Dilooshi K. Weerasooriya, Shawn P. Conley, Carl A. Bradley, Tom W. Allen, Paul D. Esker

Plant Pathology Faculty Publications

Fungicide use in the United States to manage soybean diseases has increased in recent years. The ability of fungicides to reduce disease-associated yield losses varies greatly depending on multiple factors. Nonetheless, historical data are useful to understand the broad sense and long-term trends related to fungicide use practices. In the current study, the relationship between estimated soybean yield losses due to selected foliar diseases and foliar fungicide use was investigated using annual data from 28 soybean growing states over the period of 2005 to 2015. For national and regional (southern and northern United States) scale data, mixed effects modeling was …


A Transcriptional Regulatory Network Of Rsv3-Mediated Extreme Resistance Against Soybean Mosaic Virus, Lindsay C. Demers, Neelam R. Redekar, Aardra Kachroo, Sue A. Tolin, Song Li, M. A. Saghai Maroof Apr 2020

A Transcriptional Regulatory Network Of Rsv3-Mediated Extreme Resistance Against Soybean Mosaic Virus, Lindsay C. Demers, Neelam R. Redekar, Aardra Kachroo, Sue A. Tolin, Song Li, M. A. Saghai Maroof

Plant Pathology Faculty Publications

Resistance genes are an effective means for disease control in plants. They predominantly function by inducing a hypersensitive reaction, which results in localized cell death restricting pathogen spread. Some resistance genes elicit an atypical response, termed extreme resistance, where resistance is not associated with a hypersensitive reaction and its standard defense responses. Unlike hypersensitive reaction, the molecular regulatory mechanism(s) underlying extreme resistance is largely unexplored. One of the few known, naturally occurring, instances of extreme resistance is resistance derived from the soybean Rsv3 gene, which confers resistance against the most virulent Soybean mosaic virus strains. To discern the regulatory mechanism …


Dissecting The Economic Impact Of Soybean Diseases In The United States Over Two Decades, Ananda Y. Bandara, Dilooshi K. Weerasooriya, Carl A. Bradley, Tom W. Allen, Paul D. Esker Apr 2020

Dissecting The Economic Impact Of Soybean Diseases In The United States Over Two Decades, Ananda Y. Bandara, Dilooshi K. Weerasooriya, Carl A. Bradley, Tom W. Allen, Paul D. Esker

Plant Pathology Faculty Publications

Soybean (Glycine max L. Merrill) is an economically important commodity for United States agriculture. Nonetheless, the profitability of soybean production has been negatively impacted by soybean diseases. The economic impacts of 23 common soybean diseases were estimated in 28 soybean-producing states in the U.S., from 1996 to 2016 (the entire data set consisted of 13,524 data points). Estimated losses were investigated using a variety of statistical approaches. The main effects of state, year, pre- and post-discovery of soybean rust, region, and zones based on yield, harvest area, and production, were significant on “total economic loss” as a function of …


Improving Kentucky's Winter Wheat And Double Crop Soybean Rotation, Katherine Susan Rod Jan 2020

Improving Kentucky's Winter Wheat And Double Crop Soybean Rotation, Katherine Susan Rod

Theses and Dissertations--Plant and Soil Sciences

The winter wheat double crop soybean rotation is an economically viable rotation for Kentucky farmers. Recent decreases in commodity prices has warranted the need to evaluate intensive management practices that can increase yields and profitability in this crop rotation. There were three goals of this dissertation: 1.) identify management practices that would decrease deoxynivalenol (DON) in harvested wheat grain and increase wheat heading and anthesis uniformity, 2.) evaluate double crop soybean planting timing and identify intensive management practices to increase seed yield, and 3.) determine the profitability of these management options. These studies were conducted in Princeton KY between 2016 …


Inhibition Of Fusarium Oxysporum F. Sp. Nicotianae Growth By Phenylpropanoid Pathway Intermediates, Timothy E. Shull, Jasmina Kurepa, Robert D. Miller, Natalia Martinez-Ochoa, Jan A. Smalle Jan 2020

Inhibition Of Fusarium Oxysporum F. Sp. Nicotianae Growth By Phenylpropanoid Pathway Intermediates, Timothy E. Shull, Jasmina Kurepa, Robert D. Miller, Natalia Martinez-Ochoa, Jan A. Smalle

Plant and Soil Sciences Faculty Publications

Fusarium wilt in tobacco caused by the fungus Fusarium oxysporum f. sp. nicotianae is a disease‑management challenge worldwide, as there are few effective and environmentally benign chemical agents for its control. This challenge results in substantial losses in both the quality and yield of tobacco products. Based on an in vitro analysis of the effects of different phenylpropanoid intermediates, we found that the early intermediates trans‑cinnamic acid and para‑coumaric acid effectively inhibit the mycelial growth of F. oxysporum f. sp. nicotianae strain FW316F, whereas the downstream intermediates quercetin and caffeic acid exhibit no fungicidal properties. Therefore, our in …


Virus-Induced Changes In Nuclear Proteins And Membranes In Nicotiana Benthamiana Cells, Caleb Mathias Jan 2020

Virus-Induced Changes In Nuclear Proteins And Membranes In Nicotiana Benthamiana Cells, Caleb Mathias

Theses and Dissertations--Plant Pathology

Viruses rely on host proteins to complete their life cycles. This results in alterations to normal cell physiology to processes which benefit viral processes such as replication and movement to other cells. This may involve the relocalization of host proteins away from their original subcellular targets to sites which may benefit the virus, a process that is not as well understood as it relates to the nucleus. To identify nuclear proteins that may be involved in such processes, a library of random Nicotiana benthamiana cDNAs were expressed as GFP fusions in a transgenic marker lines expressing a histone 2B:RFP nuclear …


Characterizing The Roles Of Pipecolic Acid And Reactive Oxygen Species Metabolic Enzymes In Plant Systemic Immunity, Ruiying Liu Jan 2020

Characterizing The Roles Of Pipecolic Acid And Reactive Oxygen Species Metabolic Enzymes In Plant Systemic Immunity, Ruiying Liu

Theses and Dissertations--Plant Pathology

Systemic acquired resistance (SAR), initiated by a plant upon recognition of microbial effectors, involves the generation of mobile signals at the primary infection site, which translocate to and activate defense responses in distal tissues. Among the signals contributing to SAR include salicylic acid (SA), nitric oxide (NO), reactive oxygen species (ROS), glycerol-3-phosphate (G3P), and pipecolic acid (Pip). Our previous studies show there are two branches of SAR signaling pathways in Arabidopsis: one regulated by NO/ROS-G3P and the other by SA. Both NO/ROS-G3P and SA-mediated signaling branches function in parallel during SAR. To better understand the role of Pip in SAR …


Pathogenicity, Toxigenic Potential, And Genomics Of Fusarium Graminearum And F. Meridionale Causing Ear And Stalk Rot Of Maize, Franklin Jackson Machado Jan 2020

Pathogenicity, Toxigenic Potential, And Genomics Of Fusarium Graminearum And F. Meridionale Causing Ear And Stalk Rot Of Maize, Franklin Jackson Machado

Theses and Dissertations--Plant Pathology

Gibberella ear (GER) and stalk rot (GSR) diseases of maize in Brazil are caused mainly by Fusarium meridionale, a species belonging to the Fusarium graminearum species complex (FGSC). Another species within this complex, F. graminearum sensu stricto (hereafter F. graminearum), is second in importance on maize, but is the most common species found causing Fusarium Head Blight disease of wheat in Brazil. The latter species is the predominant cause of GER and GSR in North America, where F. meridionale has not been found thus far. In this dissertation I undertook a comparative analysis of pathogenic, saprophytic, toxigenic and …


Diversity And Cross-Infection Potential Of Colletotrichum On Apples And Small Fruits In Kentucky Mixed-Fruit Orchards, Madison Julia Eaton Jan 2020

Diversity And Cross-Infection Potential Of Colletotrichum On Apples And Small Fruits In Kentucky Mixed-Fruit Orchards, Madison Julia Eaton

Theses and Dissertations--Plant Pathology

Fungi in the genus Colletotrichum cause apple, blueberry, and strawberry fruit rots, which result in significant losses for Kentucky growers. Most orchards in Kentucky are agritourism-focused and grow multiple fruits in close proximity. These mixed-fruit orchards may facilitate Colletotrichum cross-infection, which has serious management implications. Small fruit and apple Colletotrichum isolates from Kentucky orchards were characterized by morphotype, phylogenetic species identification, cross-inoculation, genome sequencing, and telomere fingerprinting. The small fruit isolates grouped into seven morphotypes, representing two species complexes: C. acutatum and C. gloeosporioides. All blueberry isolates belonged to the species C. fioriniae, and the majority of strawberry …


Arthropod Resistant Tomatoes: Screening Tools, Yield And Nutritional Quality Of Interspecific Hybrids, Mohammad Hasan Salman Ali Dawood Jan 2020

Arthropod Resistant Tomatoes: Screening Tools, Yield And Nutritional Quality Of Interspecific Hybrids, Mohammad Hasan Salman Ali Dawood

Theses and Dissertations--Plant and Soil Sciences

Tomato (Solanum lycopersicum) is one of the most economically important vegetable crops grown around globe but is a host for numerous pests and pathogens. In the future, tomato breeders will have to focus on increasing fruit quantity and on enhancing pest resistance. Many accessions of the wild relative of tomato, S. habrochaites display high levels of resistance towards arthropods such as spider mites. The presence of the sesquiterpene hydrocarbon, 7-epi-zingiberene, found in S. habrochaites type IV trichomes has been associated with arthropod resistance. However, the presence of other compounds in its trichome secretions may also be related …