Pseudomonas Syringae Type Iii Effectors: Targets And Roles In Plant Immunity,
2014
University of Nebraska-Lincoln
Pseudomonas Syringae Type Iii Effectors: Targets And Roles In Plant Immunity, Tania Y. Toruño
Center for Plant Science Innovation: Faculty Publications
Pseudomonas syringae is a Gram-negative bacterial pathogen that infects many crops. A central virulence strategy P. syringae uses to successfully infect plants is the injection of type III effector proteins (T3Es) into plant cells through a type IIII protein secretion system (T3SS). The T3SS is a molecular syringe found in many Gram-negative bacterial pathogens of plants and animals that transport T3Es from the bacterial cytosol into eukaryotic cells. T3Es disrupt host processes in the plant immune system required to restrict pathogen ingress. The plant innate immune system is divided in two branches, pathogen-associated molecular patterns (PAMP)-triggered immunity (PTI) and effector-triggered …
Reniform Nematode (Rotylenchulus Reniformis) Manipulation Of Host Root Gene Expression During Syncytium Formation In Upland Cotton (Gossypium Hirsutum),
2014
Clemson University
Reniform Nematode (Rotylenchulus Reniformis) Manipulation Of Host Root Gene Expression During Syncytium Formation In Upland Cotton (Gossypium Hirsutum), Wei Li
All Theses
Background: The semi-endoparasitic reniform nematode (Rotylenchulus reniformis) is a major yield-limiting pest of multiple crops in the tropics and sub-tropics, including upland cotton (Gossypium hirsutum). Reniform-resistant cotton varieties are urgently needed, but genes that confer resistance to reniform nematode have not been identified in any species. Parasitism by reniform nematode involves significant developmental changes in plant roots, leading to the formation of multicellular feeding structures called syncytia. Here, we present de novo transcriptomes assembled from syncytial and non-syncytial cotton roots on three sampling dates across a 12-day time course. Results: Total mRNA samples extracted from reniform-infected …
Characterization Of A Novel Fungal-Specific Gene, Fug1, In Fusarium Verticillioides,
2014
University of Arkansas, Fayetteville
Characterization Of A Novel Fungal-Specific Gene, Fug1, In Fusarium Verticillioides, John Byron Ridenour
Graduate Theses and Dissertations
Filamentous fungi are responsible for numerous plant and animal diseases. The filamentous ascomycete Fusarium verticillioides is a globally important pathogen of maize, capable of causing severe yield reductions and economic losses. Also of substantial concern is the contamination of infected kernels with fumonisins, toxic secondary metabolites linked to toxicoses in humans and livestock. The number of sequenced fungal genomes is rapidly increasing. However, functional characterization of fungal genes has not progressed at a comparable rate. In pathogenic fungi, uncharacterized genes represent a source for novel virulence factors or anti-fungal targets. Therefore, to fully understand the genetic mechanisms underlying fungal pathogenesis, …
Identification Of Root-Knot Nematodes (Meloidogyne Spp.) Of Arkansas Using Molecular Diagnostics,
2014
University of Arkansas, Fayetteville
Identification Of Root-Knot Nematodes (Meloidogyne Spp.) Of Arkansas Using Molecular Diagnostics, Churamani Khanal
Graduate Theses and Dissertations
Root-knot nematodes (Meloidogyne spp.) are highly-adaptable, obligate plant parasites distributed worldwide. In addition, root-knot nematodes are an economically important genus of plant-parasitic nematodes. Meloidogyne incognita, M. arenaria, M. javanica, M. hapla and M. graminis have been reported from Arkansas during 1964 to 1994. Previous identifications were based primarily on morphological characters and host differentials. In this study, identification using molecular diagnostics methods was performed to identify Meloidogyne species present in Arkansas. A total of 106 soil and root samples from 36 of the 75 counties were collected and processed to obtain root-knot nematodes. Polymerase chain reaction (PCR) was performed …
Dissection Of Gray Leaf Spot Of Maize Through Functional Genomics,
2014
University of Arkansas, Fayetteville
Dissection Of Gray Leaf Spot Of Maize Through Functional Genomics, Robert Louis Hirsch
Graduate Theses and Dissertations
Gray leaf spot, caused by Cercospora zeae-maydis, is a devastating disease of maize that reduces yields and increases management costs. C. zeae-maydis penetrates maize leaves through stomata, but the biological and molecular bases of this process are poorly understood. The goal of this research was to elucidate the biological parameters of stomatal infection in C. zeae-maydis, and to identify and characterize novel genetic pathways involved in stomatal sensing and pathogenesis. Histopathological observations of a GFP-expressing strain of C. zeae-maydis during infection of maize indicated that the fungus responded to host-derived stomatal cues during the infection process. C. zeae-maydis was observed …
Evaluation Of Medicago Truncatula Accessions For Triterpene Saponins And Their Potential Impacts On Plant Pests,
2014
University of Arkansas, Fayetteville
Evaluation Of Medicago Truncatula Accessions For Triterpene Saponins And Their Potential Impacts On Plant Pests, Samantha Roberson
Graduate Theses and Dissertations
Plants have developed numerous ways to protect themselves from microbes and insects, including producing secondary metabolites that negatively impact an invading pathogen or pest. Saponins are specialized metabolites found in many plant species and may play a role in protecting the plant. Though saponins are found in many plant species, triterpene saponins are found primarily in dicotyledons, including legumes. Medicago truncatula is a model system for studying legume biology and some accessions accumulate high concentrations of saponins. Accessions of M. truncatula known to have differing levels of saponins in both foliar and root tissues were tested for their suitability as …
The Phenotypic Effects And Transcript Response Of Salt Stress, The Impact Of Viral Infection On Salt Stress Symptoms, And The Effect Of Salt Stress On Soybean Virus Vector Activity In Soybean Varieties That Vary In Chloride Uptake,
2014
University of Arkansas, Fayetteville
The Phenotypic Effects And Transcript Response Of Salt Stress, The Impact Of Viral Infection On Salt Stress Symptoms, And The Effect Of Salt Stress On Soybean Virus Vector Activity In Soybean Varieties That Vary In Chloride Uptake, Alma Glenn Laney
Graduate Theses and Dissertations
With the increase in saline soils worldwide, understanding the mechanisms for salt tolerance in plants is important to reduce yield loss due to salt stress. Soybean, Glycine max (L.) Merr., genotypes differ in chloride uptake with genotypes that take up chloride into foliar tissues tending to be salt-sensitive whereas those that partially exclude chloride from the leaves are more salt-tolerant. Transcriptional and physiological responses were measured in two soybean cultivars, Clark and Manokin, which differ in chloride uptake in response to salt stress and in combination with Soybean mosaic virus (SMV) and its aphid vector, Aphis glycines . The interaction …
First Report Of Goss's Bacterial Leaf Blight And
Wilt Of Corn Caused By Clavibacter Michiganensis
Subsp. Nebraskensis In North Dakota,
2014
North Dakota State University
First Report Of Goss's Bacterial Leaf Blight And Wilt Of Corn Caused By Clavibacter Michiganensis Subsp. Nebraskensis In North Dakota, A. Friskop, K. Kinzer, M. Mcconnell, Z. Liu, K. A. Korus, A. Timmerman, T. Jackson
Department of Plant Pathology: Faculty Publications
In August of 2011, the North Dakota State University Plant Diagnostic Lab received a hybrid corn (Zea mays) leaf sample from Burleigh County in southcentral North Dakota (ND). The leaf had long, irregular, water-soaked lesions consistent with Goss's leaf blight of corn. Using a light microscope at 10× magnification, bacterial streaming was observed from the excised edge of leaf tissue. A bacterial suspension was created, streaked onto a semi-selective CNS medium (1), and incubated at 22°C. Dark yellow-orange colonies appeared on the medium after 5 days. Single colonies were subcultured onto additional CNS media. To verify the identity …
The Effect Of Agricultural Practices On Sugar Beet Root Aphid (Pemphigus Betae Doane) And Beneficial Epigeal Arthropods,
2014
University of Nebraska-Lincoln
The Effect Of Agricultural Practices On Sugar Beet Root Aphid (Pemphigus Betae Doane) And Beneficial Epigeal Arthropods, Rudolph J. Pretorius
Department of Entomology: Dissertations, Theses, and Student Research
This study investigated the effect of several agricultural practices on the sugar beet root aphid (Pemphigus betae Doane) and beneficial epigeal natural enemies in western Nebraska sugar beet agroecosystems. Eight glyphosate-tolerant sugar beet varieties were evaluated under field conditions for their resistance to root aphids. High levels of aphid resistance were detected for some varieties. In conjunction to this, pitfall sampling was conducted to determine the beneficial epigeal natural enemy complex in the area, which could contribute to the management of both root aphids and glyphosate-resistant weeds. Ground beetles comprised an important and abundant component of this fauna, with …
Spatial Distribution And Genetic Variability Of Reniform And Lance Nematodes In Cotton Agroecosystems,
2014
Clemson University
Spatial Distribution And Genetic Variability Of Reniform And Lance Nematodes In Cotton Agroecosystems, Claudia Holguin
All Dissertations
Rotylenchulus reniformis (reniform nematode) and Hoplolaimus columbus (Columbia lance nematode) are two of the main plant-pathogenic nematode species affecting cotton production in the United States. For the selection and implementation of effective management practices it is important to understand distribution patterns and population genetic structure of these two nematodes in cotton agroecosystems. In a three-year field study, the spatial distribution of reniform nematode was characterized in two commercial fields in South Carolina to determine the effects of relations with soil texture and crop rotation on reniform nematode distribution (Chapter 1). Results of this project suggest that population densities of reniform …
Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal
Virome And Is Associated With Changes In Cognitive
Functions In Humans And Mice,
2014
Johns Hopkins School of Medicine
Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Robert H. Yolken, Lorraine Jones-Brando, David D. Dunigan, Geetha Kannan, Faith Dickerson, Emily Severance, Sarven Sabunciyan, C. Conover Talbot Jr., Emese Prandovszky, James R. Gurnon, Irina V. Agarkova, Flora Leister, Kristin L. Gressitt, Ou Chen, Bryan Deuber, Fangrui Ma, Mikhail V. Pletnikov, James L. Van Etten
James Van Etten Publications
Chloroviruses (family Phycodnaviridae) are large DNA viruses known to infect certain eukaryotic green algae and have not been previously shown to infect humans or to be part of the human virome. We unexpectedly found sequences homologous to the chlorovirus Acanthocystis turfacea chlorella virus 1 (ATCV-1) in a metagenomic analysis of DNA extracted from human oropharyngeal samples. These samples were obtained by throat swabs of adults without a psychiatric disorder or serious physical illness who were participating in a study that included measures of cognitive functioning. The presence of ATCV-1 DNA was confirmed by quantitative PCR with ATCV-1 DNA being …
Co-Opted Oxysterol-Binding Orp And Vap Proteins Channel Sterols To Rna Virus Replication Sites Via Membrane Contact Sites,
2014
University of Kentucky
Co-Opted Oxysterol-Binding Orp And Vap Proteins Channel Sterols To Rna Virus Replication Sites Via Membrane Contact Sites, Daniel Barajas, Kai Xu, Isabel Fernández De Castro Martín, Zsuzsanna Sasvari, Federica Brandizzi, Cristina Risco, Peter D. Nagy
Plant Pathology Faculty Publications
Viruses recruit cellular membranes and subvert cellular proteins involved in lipid biosynthesis to build viral replicase complexes and replication organelles. Among the lipids, sterols are important components of membranes, affecting the shape and curvature of membranes. In this paper, the tombusvirus replication protein is shown to co-opt cellular Oxysterol-binding protein related proteins (ORPs), whose deletion in yeast model host leads to decreased tombusvirus replication. In addition, tombusviruses also subvert Scs2p VAP protein to facilitate the formation of membrane contact sites (MCSs), where membranes are juxtaposed, likely channeling lipids to the replication sites. In all, these events result in redistribution and …
Genetic And Aggressiveness Variation Among Sclerotinia Sclerotiorum Dry Bean Isolates From Brazil Fields,
2014
Universidade Federal de Lavras – UFLA
Genetic And Aggressiveness Variation Among Sclerotinia Sclerotiorum Dry Bean Isolates From Brazil Fields, Willian Luis Antonio Zancan, James R. Steadman, Rebecca Higgins, Rachana Jhala, Jose Da Cruz Machado
Department of Plant Pathology: Faculty Publications
Sclerotinia sclerotiorum, infection of bean fields, has increased in Brazil. Fungicides application is the control strategy used due to lack of cultivars with complete disease resistance. To guide the use of isolates in resistance screening 25 S. sclerotiorum isolates from Brazilian dry bean fields were characterized using microsatellite markers, mycelial compatibility groups (MCGs) and aggressiveness. Microsatellite primer pairs were used to identify polymorphisms among the S. sclerotiorum isolates and MCGs were determined from interaction of all isolates grown side by-side. Aggressiveness was derived from a straw test where fungal mycelium was placed over a cut bean stem and rated for …
An Eriophyid Mite-Transmitted Plant Virus Contains Eight Genomic Rna Segments With Unusual Heterogeneity In The Nucleocapsid Protein,
2014
USDA-ARS
An Eriophyid Mite-Transmitted Plant Virus Contains Eight Genomic Rna Segments With Unusual Heterogeneity In The Nucleocapsid Protein, Satyanarayana Tatineni, Anthony J. Mcmechan, Everlyne N. Wosula, Stephen N. Wegulo, Robert A. Graybosch, Roy French, Gary L. Hein
Department of Plant Pathology: Faculty Publications
Eriophyid mite-transmitted, multipartite, negative-sense RNA plant viruses with membrane-bound spherical virions are classified in the genus Emaravirus. We report here that the eriophyid mite-transmitted Wheat mosaic virus (WMoV), an Emaravirus, contains eight genomic RNA segments, the most in a known negative-sense RNA plant virus. Remarkably, two RNA 3 consensus sequences, encoding the nucleocapsid protein, were found with 12.5% sequence divergence, while no heterogeneity was observed in the consensus sequences of additional genomic RNA segments. The RNA-dependent RNA polymerase, glycoprotein precursor, nucleocapsid, and P4 proteins of WMoV exhibited limited sequence homology with the orthologous proteins of other emaraviruses, while …
Effect Of Post-Anthesis Fungicide Applications To Manage Fusarium Head Blight In Winter Wheat,
2014
Purdue University
Effect Of Post-Anthesis Fungicide Applications To Manage Fusarium Head Blight In Winter Wheat, Anna Noversoke
Open Access Theses
Fusarium head blight (FHB) of wheat, caused by the fungus Fusarium graminearum, is currently considered one of the most economically important diseases on wheat in the North Central United States. The fungus causes light-weight "tombstone" grains to form and produces the mycotoxin deoxynivalenol (DON), reducing the yield and quality of the grain. Currently, farmers rely heavily on the sterol demethylase Inhibitor (DMI) triazole fungicide Prosaro (Bayer CropScience) to protect their crop from this disease. The optimal fungicide application timing is traditionally believed to be early anthesis - Feekes Growth Stage (FGS) 10.5.1. However, environmental conditions and uneven flowering across a …
Effects Of Ocean Acidification On Chlorophyll Content,
2014
Chapman University
Effects Of Ocean Acidification On Chlorophyll Content, C. Del Fierro, R. Lloyd, H. El-Askary
e-Research: A Journal of Undergraduate Work
Airborne pollutants contribute to ocean acidification and hence to the associated chlorophyll content level. Previous work showed that falling aerosols causing ocean acidification would in turn result in bleaching and productivity loss in coral reef builders. Chlorophyll content has been used as a measure of the concentration of the photosynthetic pigment chlorophyll a (the most common "green" chlorophyll) in the ocean. In our work we have monitored the change in chlorophyll content obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on board Terra/Aqua satellites from 2000-2009 over selected pilot areas. Moreover, we have used the Goddard Chemistry Aerosol Radiation …
Chlorovirus Skp1-Binding Ankyrin Repeat Protein Interplay And
Mimicry Of Cellular Ubiquitin Ligase Machinery,
2014
University of Nebraska-Lincoln
Chlorovirus Skp1-Binding Ankyrin Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric A. Noel, Ming Kang, Jiri Adamec, James L. Van Etten, George A. Oyler
James Van Etten Publications
The ubiquitin-proteasome system is targeted by many viruses that have evolved strategies to redirect host ubiquitination machinery. Members of the genus Chlorovirus are proposed to share an ancestral lineage with a broader group of related viruses, nucleo-cytoplasmic large DNA viruses (NCLDV). Chloroviruses encode an Skp1 homolog and ankyrin repeat (ANK) proteins. Several chlorovirus-encoded ANK repeats contain C-terminal domains characteristic of cellular F-boxes or related NCLDV chordopox PRANC (pox protein repeats of ankyrin at C-terminal) domains. These observations suggested that this unique combination of Skp1 and ANK repeat proteins might form complexes analogous to the cellular Skp1-Cul1-F-box (SCF) ubiquitin ligase complex. …
A Novel Partitivirus That Confers Hypovirulence On Plant Pathogenic Fungi,
2014
Huazhong Agricultural University, China
A Novel Partitivirus That Confers Hypovirulence On Plant Pathogenic Fungi, Xueqiong Xiao, Jiasen Cheng, Jinghua Tang, Yanping Fu, Daohong Jiang, Timothy S. Baker, Said A. Ghabrial, Jiatao Xie
Plant Pathology Faculty Publications
Members of the family Partitiviridae have bisegmented double-stranded RNA (dsRNA) genomes and are not generally known to cause obvious symptoms in their natural hosts. An unusual partitivirus, Sclerotinia sclerotiorum partitivirus 1 (SsPV1/WF-1), conferred hypovirulence on its natural plant-pathogenic fungal host, Sclerotinia sclerotiorum strain WF-1. Cellular organelles, including mitochondria, were severely damaged. Hypovirulence and associated traits of strain WF-1 and SsPV1/WF-1 were readily cotransmitted horizontally via hyphal contact to different vegetative compatibility groups of S. sclerotiorum and interspecifically to Sclerotinia nivalis and Sclerotinia minor. S. sclerotiorum strain 1980 transfected with purified SsPV1/WF-1 virions also exhibited hypovirulence and associated traits similar …
Phytochemical, Antioxidant And Antibacterialpotential Of Elaeagnus Kologa (Schlecht.) Leaf.,
2014
Stanford University
Phytochemical, Antioxidant And Antibacterialpotential Of Elaeagnus Kologa (Schlecht.) Leaf., Zoe Merculieff, Shubharani Ramnath, Seethalakshmi Madhukar Sankoli, Sivaram Venkataramegowda, Ganti S. Murthy, Ruben Michael Ceballos
Biological Sciences Faculty Publications and Presentations
Objective To screen different solvent extracts of Elaeagnus kologa (E. kologa) leaf to determine the phytochemicals, potent antioxidant and antibacterial activity to find out the possible source of applied pharmaceutical formulations. Methods Solvent extracts of leaf material were prepared using the Soxhlet apparatus. A study was performed on antioxidant activity of methanolic extract of leaf by 1-1-diphenyl-2-picrylhydrazyl method. The phenolic and flavonoid content of all the fractions were determined using high performance liquid chromatography. Leaves were also subjected to protein and carbohydrate test. Results The total phenols, flavonoids were found to be high in petroleum ether as compare to other …
Diversity Of Bacteria Carried By Pinewood Nematode In
Usa And Phylogenetic Comparison With Isolates From
Other Countries,
2014
University of Coimbra, Portugal
Diversity Of Bacteria Carried By Pinewood Nematode In Usa And Phylogenetic Comparison With Isolates From Other Countries, Diogo Neves Proença, Luís Fonseca, Thomas Powers, Isabel M.O. Abrantes, Paula V. Morais
Department of Plant Pathology: Faculty Publications
Pine wilt disease (PWD) is native to North America and has spread to Asia and Europe. Lately, mutualistic relationship has been suggested between the pinewood nematode (PWN), Bursaphelenchus xylophilus the causal nematode agent of PWD, and bacteria. In countries where PWN occurs, nematodes from diseased trees were reported to carry bacteria from several genera. However no data exists for the United States. The objective of this study was to evaluate the diversity of the bacterial community carried by B. xylophilus, isolated from different Pinus spp. with PWD in Nebraska, United States. The bacteria carried by PWN belonged to Gammaproteobacteria …
