Plant Pathology Commons^™

Activation Of A Coi1-Dependent Pathway In Arabidopsis By Pseudomonas Syringae Type Iii Effectors And Coronatine, Ping He, Satya Chintamanani, Zhongying Chen, Lihuang Zhu, Barbara N. Kunkel, James R. Alfano, Xiaoyan Tang, Jian-Min Zhou

Center for Plant Science Innovation: Faculty Publications

Gram-negative bacteria use a variety of virulence factors including phytotoxins, exopolysaccharides, effectors secreted by the type III secretion system, and cell-wall-degrading enzymes to promote parasitism in plants. However, little is known about how these virulence factors alter plant celluar responses to promote disease. In this study, we show that virulent Pseudomonas syringae strains activate the transcription of an Arabidopsis ethylene response factor (ERF) gene, RAP2.6, in a coronatine insensitive 1 (COI1)-dependent manner. A highly sensitive RAP2.6 promoter-firely luciferase (RAP2.6-LUC) reporter line was developed to monitor activities of various bacterial virulence genes. Analyses of P. syringae pv. tomato DC3000 mutants indicated …

The Complete Genome Sequence Of The Arabidopsis And Tomato Pathogen Pseudomonas Syringae Pv. Tomato Dc3000, C. Robin Buell, Vinita Joardar, Magdalen Lindeberg, Jeremy Selengut, Ian T. Paulsen, Michelle L. Gwinn, Robert J. Dodson, Robert T. Deboy, A. Scott Durkin, James F. Kolonay, Ramana Radupu, Sean Daugherty, Lauren Brinkac, Maureen J. Beanan, Daniel H. Haft, William C. Nelson, Tanja Davidsen, Nikhat Zafar, Liwei Zhou, Jia Liu, Qiaoping Yuan, Hoda Khouri, Nadia Fedorova, Bao Tran, Daniel Russell, Kristi Berry, Teresa Utterback, Susan E. Van Aken, Tamara V. Feldblyum, Mark D'Ascenzo, Wen-Ling Deng, Adela R. Ramos, James R. Alfano, Samuel Cartinhour, Arn K. Chatterjee, Terrence P. Delaney, Sondra G. Lazarowitz, Gregory B. Martin, David J. Schneider, Xiaoyan Tang, Carol L. Bender, Owen White, Claire M. Fraser, Alan Collmer

Department of Plant Pathology: Faculty Publications

We report the complete genome sequence of the model bacterial pathogen Pseudomonas syringae pathovar tomato DC3000 (DC3000), which is pathogenic on tomato and Arabidopsis thaliana. The DC3000 genome (6.5 megabases) contains a circular chromosome and two plasmids, which collectively encode 5,763 ORFs. We identified 298 established and putative virulence genes, including several clusters of genes encoding 31 confirmed and 19 predicted type III secretion system effector proteins. Many of the virulence genes were members of paralogous families and also were proximal to mobile elements, which collectively comprise7%of the DC3000 genome. The bacterium possesses a large repertoire of transporters for …

Effects Of Modification Of The Transcription Initiation Site Context On Citrus Tristeza Virus Subgenomic Rna Synthesis, Maria A. Ayllon, Siddarame Gowda, Satyanarayana Tatineni, Alexander V. Karasev, Scott Adkins, Munir Mawassi, Jose Guerri, Pedro Moreno, William O. Dawson

Department of Plant Pathology: Faculty Publications

Citrus tristeza virus (CTV), a member of the Closteroviridae, has a positive-sense RNA genome of about 20 kb organized into 12 open reading frames (ORFs). The last 10 ORFs are expressed through 3'-coterminal subgenomic RNAs (sgRNAs) regulated in both amounts and timing. Additionally, relatively large amounts of complementary sgRNAs are produced. We have been unable to determine whether these sgRNAs are produced by internal promotion from the full-length template minus strand or by transcription from the minus-stranded sgRNAs. Understanding the regulation of 10 sgRNAs is a conceptual challenge. In analyzing commonalities of a replicase complex in producing so many …

Use Of A 3 Cytoplasm To Reduce Risk Of Gene Flow Through Sorghum Pollen, Jeffrey F. Pedersen, D. B. Marx, Deanna L. Funnell

Department of Plant Pathology: Faculty Publications

A critical impediment to field testing and deployment of transgenic sorghum [Sorghum bicolor (L.) Moench] is the threat of gene flow to weedy relatives through pollen. A technique using sorghum with A₃ cytoplasmic male sterility to control transgene flow through pollen while using nontransgenic pollinators is described and an experiment was designed to evaluate the risk of viable pollen flow using A₃ hybrids under field conditions. Seed set under pollinating bags (an indicator of fertile pollen) was evaluated at the University of Nebraska Field Laboratory at Ithaca, NE, in 2001 and 2002 on selfed F₂ progeny …

Bcl-2 Family Members Inhibit Oxidative Stress-Induced Programmed Cell Death In Saccharomyces Cerevisiae, Shao-Rong Chen, David Dunigan, Martin Dickman

Department of Plant Pathology: Faculty Publications

Selected antiapoptotic genes were expressed in baker’s yeast (Saccharomyces cerevisiae) to evaluate cytoprotective effects during oxidative stress. When exposed to treatments resulting in the generation of reactive oxygen species (ROS), including H₂O₂, menadione, or heat shock, wild-type yeast died and exhibited apoptotic-like characteristics, consistent with previous studies. Yeast strains were generated expressing nematode ced-9, human bcl-2, or chicken bcl-xl genes. These transformants tolerated a range of oxidative stresses, did not display features associated with apoptosis, and remained viable under conditions that were lethal to wildtype yeast. Yeast strains expressing a mutant antiapoptotic gene (bcl-2 …

Induced Resistance As A Mechanism Of Biological Control By Lysobacter Enzymogenes Strain C3, Ozlem Kilic-Ekici, Gary Y. Yuen

Department of Plant Pathology: Faculty Publications

Induced resistance was found to be a mechanism for biological control of leaf spot, caused by Bipolaris sorokiniana, in tall fescue (Festuca arundinacea) using the bacterium Lysobacter enzymogenes strain C3. Resistance elicited by C3 suppressed germination of B. sorokiniana conidia on the phylloplane in addition to reducing the severity of leaf spot. The pathogen-inhibitory effect could be separated from antibiosis by using heat-inactivated cells of C3 that retained no antifungal activity. Application of live or heat-killed cells to tall fescue leaves resulted only in localized resistance confined to the treated leaf, whereas treatment of roots resulted in …

Evolution Of Wheat Streak Mosaic Virus: Dynamics Of Population Growth Within Plants May Explain Limited Variation, Roy C. French, Drake C. Stenger

Department of Plant Pathology: Faculty Publications

Like many other plant RNA viruses, Wheat streak mosaic virus (WSMV) sequence diversity within and among infected plants is low given the large number of virions produced. This may be explained by considering aspects of plant virus life history. Intracellular replication of RNA viruses is predominately linear, not exponential, which means that the rate at which mutations accumulate also is linear. Bottlenecks during systemic movement further limit diversity. Analysis of mixed infections with two WSMV isolates suggests that about four viral genomes participate in systemic invasion of each tiller. Low effective population size increases the role of stochastic processes on …

Review Of Molecular Biology Of Fungal Development, Mycology Series, Volume 15, Marty Dickman

Department of Plant Pathology: Faculty Publications

Numerous publications, books, and textbooks are available that treat the subject of developmental biology. Far less is available detailing the fungi, an important group of organisms that have implications in a broad variety of contexts from medical to agricultural to food, and of course as model systems for “higher” eukaryotes. This nicely edited book by Osiewacz is an attempt to fill that gap. He has compiled an impressive list of authors, who represent leaders in their respective fields. This gives readers a detailed and current view of a broad array of fungal processes and lifestyles, ranging from saprophytes to pathogens …

Proceedings Of The 30th Annual Meeting, Southern Soybean Disease Workers (March 3, 2003, Little Rock, Arkansas), Patrick Fenn, Kathy S. Mclean, Boyd Padgett, Jason Bond, Steve R. Koenning

Southern Soybean Disease Workers: Conference Proceedings

Contents

Southern Soybean Disease Workers 2002 treasury report. James Bond

United States Soybean Disease Loss Estimate for 2002. Compiled by Stephen R. Koenning

Evaluation of Reduced Rates and Timing of Azoxystrobin on Frogeye Leaf Spot Cliff M Coker

Effect of Fungicides on Soybean Disease, Yield and Seed Quality. RW Schneider, JD Siebert, CA Jones, and JL Griffin

Effect of Fungicide Seed Treatment on Soybean Establishment. ML Rosso, C Boger, G Bates, C Rothrock, T Kirkpatrick, and J Rupe

Influence of Soybean Cyst Nematode on Sudden Death Syndrome Development in Field Microplots in Arkansas. SL Giammaria, CB Boger, and JC Rupe …

Unusual Life Style Of Giant Chlorella Viruses, James L. Van Etten

Department of Plant Pathology: Faculty Publications

Paramecium bursaria chlorella virus (PBCV-1) is the prototype of a family of large, icosahedral, plaque-forming, dsDNA viruses that replicate in certain unicellular, eukaryotic chlorella-like green algae. Its 330-kb genome contains ~373 protein-encoding genes and 11 tRNA genes. The predicted gene products of ~50% of these genes resemble proteins of known function, including many that are unexpected for a virus, e.g., ornithine decarboxylase, hyaluronan synthase, GDP-D-mannose 4,6 dehydratase, and a potassium ion channel protein. In addition to their large genome size, the chlorella viruses have other features that distinguish them from most viruses. These features include: (a) The viruses encode multiple …

A Protein Kinase From Colletotrichum Trifolii Is Induced By Plant Cutin And Is Required For Appressorium Formation, M. B. Dickman, Y.-S. Ha, Z. Yang, B. J. Adams, C. Huang

Department of Plant Pathology: Faculty Publications

When certain phytopathogenic fungi contact plant surfaces, specialized infection structures (appressoria) are produced that facilitate penetration of the plant external barrier; the cuticle. Recognition of this hydrophobic host surface must be sensed by the fungus, initiating the appropriate signaling pathway or pathways for pathogenic development. Using polymerase chain reaction and primers designed from mammalian protein kinase C sequences (PKC), we have isolated, cloned, and characterized a protein kinase from Colletotrichum trifolii, causal agent of alfalfa anthracnose. Though sequence analysis indicated conserved sequences in mammalian PKC genes, we were unable to induce activity of the fungal protein using known activators …

The Pseudomonas Syringae Type Iii-Secreted Protein Hopptod2 Possesses Protein Tyrosine Phosphatase Activity And Suppresses Programmed Cell Death In Plants, Avelina Espinosa, Ming Guo, Vincent C. Tam, Zheng Qing Fu, James R. Alfano

Center for Plant Science Innovation: Faculty Publications

The bacterial plant pathogen Pseudomonas syringae possesses a type III protein secretion system that delivers many virulence proteins into plant cells. A subset of these proteins (called Avr proteins) is recognized by the plant’s innate immune system and triggers defences. One defence-associated response is the hypersensitive response (HR), a programmed cell death (PCD) of plant tissue. We have previously identified HopPtoD2 as a type III secreted protein from P. s. pv. tomato DC3000. Sequence analysis revealed that an N-terminal domain shared homology with Avr- PphD and a C-terminal domain was similar to protein tyrosine phosphatases (PTPs). We demonstrated that purified …

Are Chlorella Viruses A Rich Source Of Ion Channel Genes?, Ming Kang, Anna Moroni, Sabrina Gazzarrini, James L. Van Etten

Department of Plant Pathology: Faculty Publications

Plaque-forming dsDNA (>330 kb) viruses that infect certain unicellular, eukaryotic chlorella-like green algae contain ~375 protein-encoding genes. These proteins include a 94 amino acid K+ channel protein, called Kcv, as well as two putative ligand-gated ion channels. The viruses also encode other proteins that could be involved in the assembly and/ or function of ion channels, including protein kinases and a phosphatase, polyamine biosynthetic enzymes and histamine decarboxylase.

Fungal Biology And Agriculture: Revisiting The Field, O. Yarden, D. J. Ebbole, S. Freeman, R. J. Rodriguez, M. B. Dickman

Department of Plant Pathology: Faculty Publications

Plant pathology has made significant progress over the years, a process that involved overcoming a variety of conceptual and technological hurdles. Descriptive mycology and the advent of chemical plant-disease management have been followed by biochemical and physiological studies of fungi and their hosts. The later establishment of biochemical genetics along with the introduction of DNA-mediated transformation have set the stage for dissection of gene function and advances in our understanding of fungal cell biology and plant–fungus interactions. Currently, with the advent of high-throughput technologies, we have the capacity to acquire vast data sets that have direct relevance to the numerous …

Transcription Strategy In A Closterovirus: A Novel 5'-Proximal Controller Element Of Citrus Tristeza Virus Produces 5'- And 3'-Terminal Subgenomic Rnas And Differs From 3' Open Reading Frame Controller Elements, Siddarame Gowda, Maria A. Ayllon, Satyanarayana Tatineni, Moshe Bar-Joseph, William O. Dawson

Department of Plant Pathology: Faculty Publications

Citrus tristeza virus (CTV) produces more than thirty 3'- or 5'-terminal subgenomic RNAs (sgRNAs) that accumulate to various extents during replication in protoplasts and plants. Among the most unusual species are two abundant populations of small 5'-terminal sgRNAs of approximately 800 nucleotides (nt) termed low-molecular-weight tristeza (LMT1 and LMT2) RNAs. Remarkably, CTV replicons with all 10 3' genes deleted produce only the larger LMT1 RNAs. These 5'-terminal positive-sense sgRNAs do not have corresponding negative strands and were hypothesized to be produced by premature termination during plus-strand genomic RNA synthesis. We characterized a cis-acting element that controls the production …

Evaluation Of Resistance Screening Methods For Sclerotinia Stem Rot Of Soybean And Dry Bean, Linda S. Kull, Tri D. Vuong, Kris S. Powers, Kent M. Eskridge, James R. Steadman, Glen L. Hartman

Department of Plant Pathology: Faculty Publications

Three methods to identify levels of resistance to Sclerotinia sclerotiorum in soybean (Glycine max) and dry bean (Phaseolus vulgaris) were compared using multiple data analyses. The three methods were mycelial plug inoculations of cotyledons, cut stems, and detached leaves. Six S. sclerotiorum isolates of known relative aggressiveness were inoculated on each of three soybean and dry bean cultivars with varied response to S. sclerotiorum. For soybean, all three inoculation methods accurately identified isolate aggressiveness irrespective of cultivar, but identification of susceptible and partially resistant soybean cultivars was influenced by isolate. For dry bean, the cotyledon and cut …

An Evolutionary Perspective Of Pierce’S Disease Of Grapevine, Citrus Variegated Chlorosis, And Mulberry Leaf Scorch Diseases, Jianchi Chen, John S. Hartung, Chung-Jan Chang, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

Xylella fastidiosa causes diseases on a growing list of economically important plants. An understanding of how xylellae diseases originated and evolved is important for disease prevention and management. In this study, we evaluated the phylogenetic relationships of X. fastidiosa strains from citrus, grapevine, and mulberry through the analyses of random amplified polymorphic DNAs (RAPDs) and conserved 16S rDNA genes. RAPD analysis emphasized the vigorous genome-wide divergence of X. fastidiosa and detected three clonal groups of strains that cause Pierce’s disease (PD) of grapevine, citrus variegated chlorosis (CVC), and mulberry leaf scorch (MLS). Analysis of 16S rDNA sequences also identified the …

Relationship Between Secondary Metabolism And Fungal Development, Ana M. Calvo, Richard A. Wilson, Jin Woo Bok, Nancy P. Keller

Fungal Molecular Plant-Microbe Interactions

Details findings related to the relationship between secondary metabolism and fungal development.

Uses Of Antimicrobials In Plant Agriculture, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

Bacterial diseases of plants are less prevalent than diseases caused by fungi and viruses. Antimicrobials for prophylactic treatment of bacterial diseases of plants are limited in availability, use, and efficacy, and therapeutic use is largely ineffective. Most applications are by spray treatments in orchards. Monitoring and surveillance for drug resistance are not routinely done. In the United States, data on use of antimicrobials for treatment of bacterial diseases of plants are limited to streptomycin and oxytetracycline. Resistance to streptomycin has become widespread among bacterial phytopathogens; no resistance among these bacteria has yet been reported for oxytetracycline. No human health effects …

Isolation And Characterization Of Endophytic Colonizing Bacteria From Agronomic Crops And Prairie Plants, Denise K. Zinniel, Patricia A. Lambrecht, N. Beth Harris, Zhengyu Feng, Daniel Kuczmarski, Phyllis Higley, Carol A. Ishimaru, Alahari Arunakumari, Raul G. Barletta, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

Endophytic bacteria reside within plant hosts without causing disease symptoms. In this study, 853 endophytic strains were isolated from aerial tissues of four agronomic crop species and 27 prairie plant species. We determined several phenotypic properties and found approximately equal numbers of gram-negative and gram-positive isolates. In a greenhouse study, 28 of 86 prairie plant endophytes were found to colonize their original hosts at 42 days postinoculation at levels of 3.5 to 7.7 log₁₀ CFU/g (fresh weight). More comprehensive colonization studies were conducted with 373 corn and sorghum endophytes. In growth room studies, none of the isolates displayed pathogenicity, …

Proceedings Of The 27th Annual Meeting, Southern Soybean Disease Workers (April 6-8, 2000, Fort Walton Beach Florida), John S. Russin, Stephen R. Koenning, Raymond W. Schneider, Peggy S. King

Southern Soybean Disease Workers: Conference Proceedings

Contents

Southern United States Soybean Disease Loss Estimate for 1999. Compiled by SR Koenning

Treasury report. Peggy S King

Invited presentation

Bean Pod Mottle: A Soybean Disease on the Rise in the New Millennium. SA Ghabrial

Contributed papers

Response of Selected Mid-South Soybean Varieties to the Reniform Nematode. GW Lawrence, KS McLean, and SM Baird

Field Response of Soybean Cultivars to the Reniform Nematode Rotylenchulus reniformis. PS King, DB Weaver, and R Rodriguez-Kabana

Approaches to Race Determination in Soybean Cyst Nematode. AJ Palmateer, ME Schmidt, SR Stetina, and JS Russin

Nematological Survey of Selected Soybean and Cotton Fields in …

Characterization Of The Aspergillus Nidulans 14-3-3 Homologue, Arta, Peter R. Kraus, Amy F. Hoffman, Steven D. Harris

Department of Plant Pathology: Faculty Publications

The 14-3-3 family of proteins function as small adaptors that facilitate a diverse array of cellular processes by mediating specific protein interactions. One such process is the DNA damage checkpoint, where these proteins prevent inappropriate activation of cyclin-dependent kinases. The filamentous fungus Aspergillus nidulans possesses a highly conserved 14- 3-3 homologue (artA) that may function in an analogous manner to prevent septum formation. However, instead of blocking septation, over-expression of artA causes a severe delay in the polarization of conidiospores. This observation suggests that these proteins play an important role in hyphal morphogenesis.

The Shca Protein Is A Molecular Chaperone That Assists In The Secretion Of The Hoppsya Effector From The Type Iii (Hrp) Protein Secretion System Of Pseudomonas Syringae, Karin V. Van Dijk, Vincent C. Tam, Angela R. Records, Tanja Petnicki-Ocwieja, James R. Alfano

Center for Plant Science Innovation: Faculty Publications

Pseudomonas syringae uses a type III protein secretion system encoded by the Hrp pathogenicity island (Pai) to translocate effector proteins into plant cells. One of these effector proteins is HopPsyA. A small open reading frame (ORF), named shcA, precedes the hopPsyA gene in the Hrp Pai of P. s. syringae 61. The predicted amino acid sequence of shcA shares general characteristics with chaperones used in type III protein secretion systems of animal pathogens. A functionally non-polar deletion of shcA in P. s. syringae 61 resulted in the loss of detectable HopPsyA in supernatant fractions, consistent with ShcA acting as a …

Phylogenetic Relationships, Strain Diversity And Biogeography Of Tritimoviruses, Frank Rabenstein, Dallas L. Seifers, Jorg Schubert, Roy C. French, Drake C. Stenger

Department of Plant Pathology: Faculty Publications

North American and Eurasian isolates of Wheat streak mosaic virus (WSMV; genus Tritimovirus) and Oat necrotic mottle virus (ONMV; genus Rymovirus) were examined. Nine WSMV isolates differentially infected oat, barley, inbred maize line SDp2 and sorghum line KS56. The WSMV isolates clustered into groups based on phylogenetic analyses of the capsid protein (CP) cistron and flanking regions. WSMV isolates from the United States (US) and Turkey were closely related, suggesting recent movement between continents. Although more divergent, WSMV from Iran (WSMV-I) also shared a most recent common ancestor with the US and Turkish isolates. Another group of WSMV …

Genomewide Identification Of Pseudomonas Syringae Pv.Tomato Dc3000 Promoters Controlled By The Hrpl Alternative Sigma Factor, Derrick E. Fouts, Robert B. Abramovitch, James R. Alfano, Angela M. Baldo, C. Robin Buell, Samuel Cartinhour, Arn K. Chatterjee, Mark D'Ascenzo, Michelle L. Gwinn, Sondra G. Lazarowitz, Na-Chun Lin, Gregory B. Martin, Amos H. Rehm, David J. Schneider, Karin V. Van Dijk, Xiaoyan Tang, Alan Collmer

Center for Plant Science Innovation: Faculty Publications

The ability of Pseudomonas syringae pv. tomato DC3000 to parasitize tomato and Arabidopsis thaliana depends on genes activated by the HrpL alternative sigma factor. To support various functional genomic analyses of DC3000, and specifically, to identify genes involved in pathogenesis, we developed a draft sequence of DC3000 and used an iterative process involving computational and gene expression techniques to identify virulence-implicated genes downstream of HrpLresponsive promoters. Hypersensitive response and pathogenicity (Hrp) promoters are known to control genes encoding the Hrp (type III protein secretion) machinery and a few type III effector proteins in DC3000. This process involved (i) identification of …

Functional Characterization And Localization Of The Aspergillus Nidulan Formin Sepa, Kathryn E. Sharpless, Steven D. Harris

Department of Plant Pathology: Faculty Publications

Formins are a family of multidomain scaffold proteins involved in actin-dependent morphogenetic events. In Aspergillus nidulans, the formin SEPA participates in two actin-mediated processes, septum formation and polarized growth. In this study, we use a new null mutant to demonstrate that SEPA is required for the formation of actin rings at septation sites. In addition, we find that a functional SEPA::GFP fusion protein localizes simultaneously to septation sites and hyphal tips, and that SEPA colocalizes with actin at each site. Using live imaging, we show that SEPA localization at septation sites and hyphal tips is dynamic. Notably, at septation …

Adenylyl Cyclase Functions Downstream Of The Gα Protein Gpa1 And Controls Mating And Pathogenicity Of Cryptococcus Neoformans, J. Andrew Alspaugh, Read Pukkila-Worley, Toshiaki Harashima, Lora M. Cavallo, Deanna L. Funnell, Gary M. Cox, John R. Perfect, James W. Kronstad, Joseph Heitman

Department of Plant Pathology: Faculty Publications

The signaling molecule cyclic AMP (cAMP) is a ubiquitous second messenger that enables cells to detect and respond to extracellular signals. cAMP is generated by the enzyme adenylyl cyclase, which is activated or inhibited by the Gα subunits of heterotrimeric G proteins in response to ligand-activated G-protein-coupled receptors. Here we identified the unique gene (CAC1) encoding adenylyl cyclase in the opportunistic fungal pathogen Cryptococcus neoformans. The CAC1 gene was disrupted by transformation and homologous recombination. In stark contrast to the situation for Saccharomyces cerevisiae, in which adenylyl cyclase is essential, C. neoformans cac1 mutant strains were viable and …

Mapping Of The P1 Proteinase Cleavage Site In The Polyprotein Of Wheat Streak Mosaic Virus (Genus Tritimovirus), Il-Ryong Choi, Kempton M. Horken, Drake C. Stenger, Roy C. French

Department of Plant Pathology: Faculty Publications

Monopartite members of the family Potyviridae utilize three virus-encoded proteinases to cleave the viral polyprotein into mature proteins. The amino-terminal region of the viral polyprotein is autolytically cleaved by the P1 proteinase. A domain required for P1 proteinase activity of Wheat streak mosaic virus (WSMV) was mapped using a series of templates with nested 3’-truncations or 5’-deletions to program in vitro transcription–translation reactions. The WSMV P1 proteinase cleavage site was mapped to a position downstream of amino acid residue 348 and upstream of amino acid residue 353, with the peptide bond between amino acid residues Y ₃₅₂ and G _{353 …}

Bean Pod Mottle Virus: A Threat To U.S. Soybean Production, Loren J. Giesler, Said A. Ghabrial, Thomas E. Hunt, John H. Hill

Department of Plant Pathology: Faculty Publications

Bean pod mottle virus (BPMV) is widespread in the major soybean-growing areas in the southern and southeastern United States. A severe outbreak of BPMV in the north central and northern Great Plains states is currently causing serious concern to soybean growers and to the soybean industry in this region (30). BPMV is efficiently transmitted in nature, within and between soybean fields, by several species of leaf-feeding beetles. The deleterious effects of BPMV infection not only reduce yield but also reduce seed quality, as seeds from infected plants may be discolored. Furthermore, BPMV predisposes soybeans to Phomopsis spp. seed infection (85), …

Isolation And Characterization Of A Virus That Infects Emiliania Huxleyi (Haptophyta), Tonje Castberg, Runar Thyrhaug, Aud Larsen, Ruth-Anne Sandaa, Mikal Heldal, James L. Van Etten, Gunnar Bratbak

Department of Plant Pathology: Faculty Publications

The isolation and characterization of a virus (designated EhV) that infects the marine coccolithophorid Emiliania huxleyi (Lohmann) Hay & Mohler are described. Three independent clones of EhV were isolated from Norwegian coastal waters in years 1999 and 2000. EhV is a double-stranded DNA-containing virus with a genome size of ~415 kilo-base pairs. The viral particle is an icosahedron with a diameter of 160–180 nm. The virus particle contains at least nine proteins ranging from 10 to 140 kDa; the major capsid protein weighs ~54 kDa. EhV has a latent period of 12–14 h and a burst size of 400–1,000 (mean, …