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Whole-Genome Expression Profiling Defines The Hrpl Regulon Of Pseudomonas Syringae Pv. Tomato Dc3000, Allows De Novo Reconstruction Of The Hrp Cis Element, And Identifies Novel Coregulated Genes, Adriana O. Ferreira, Christopher R. Myers, Jeffrey S. Gordon, Gregory B. Martin, Monica Vencato, Alan Collmer, Misty D. Wehling, James R. Alfano, Gabriel Moreno-Hagelsieb, Warren F. Lamboy, Geneviene Declerck, David J. Schneider, Samuel W. Cartinhour Nov 2006

Whole-Genome Expression Profiling Defines The Hrpl Regulon Of Pseudomonas Syringae Pv. Tomato Dc3000, Allows De Novo Reconstruction Of The Hrp Cis Element, And Identifies Novel Coregulated Genes, Adriana O. Ferreira, Christopher R. Myers, Jeffrey S. Gordon, Gregory B. Martin, Monica Vencato, Alan Collmer, Misty D. Wehling, James R. Alfano, Gabriel Moreno-Hagelsieb, Warren F. Lamboy, Geneviene Declerck, David J. Schneider, Samuel W. Cartinhour

Papers in Plant Pathology

Pseudomonas syringae pv. tomato DC3000 is a model pathogen of tomato and Arabidopsis that uses a hypersensitive response and pathogenicity (Hrp) type III secretion system (T3SS) to deliver virulence effector proteins into host cells. Expression of the Hrp system and many effector genes is activated by the HrpL alternative sigma factor. Here, an open reading frame-specific whole-genome microarray was constructed for DC3000 and used to comprehensively identify genes that are differentially expressed in wild-type and ΔhrpL strains. Among the genes whose differential regulation was statistically significant, 119 were upregulated and 76 were downregulated in the wild-type compared with the ΔhrpL ...


Microbial Content Of Abattoir Wastewater And Its Contaminated Soil In Lagos, Nigeria, A. O. Adesemoye, B. O. Opere, S. C. O. Makinde Oct 2006

Microbial Content Of Abattoir Wastewater And Its Contaminated Soil In Lagos, Nigeria, A. O. Adesemoye, B. O. Opere, S. C. O. Makinde

Papers in Plant Pathology

Microbial content of wastewater in two abattoirs and the impact on microbial population of receiving soil was studied in Agege and Ojo Local Government Areas in Lagos State, Nigeria. Wastewater samples were collected from each of the abattoirs over three months period and examined for microbial content. Soil samples contaminated with the wastewaters were also collected and analyzed for microbial content as compared to soil without wastewater contamination in the neighborhood (control). Some physico-chemical parameters of the samples such as total dissolved solid, chemical oxygen demand, etc., were examined. The wastewater samples from both abattoirs were highly contaminated; Agege abattoir ...


Genetic Characterization And Diversity Of Rathayibacter Toxicus, Irina V. Agarkova, A. K. Vidaver, E. N. Postnikova, I. T. Riley, N. W. Schaad Oct 2006

Genetic Characterization And Diversity Of Rathayibacter Toxicus, Irina V. Agarkova, A. K. Vidaver, E. N. Postnikova, I. T. Riley, N. W. Schaad

Papers in Plant Pathology

Rathayibacter toxicus is a nematode-vectored gram-positive bacterium responsible for a gumming disease of grasses and production of a highly potent animal and human toxin that is often fatal to livestock and has a history of occurring in unexpected circumstances. DNA of 22 strains of R. toxicus from Australia were characterized using amplified fragment length polymorphism (AFLP) and pulsed-field gel electrophoresis (PFGE). AFLP analysis grouped the 22 strains into three genetic clusters that correspond to their geographic origin. The mean similarity between the three clusters was 85 to 86%. PFGE analysis generated three different banding patterns that enabled typing the strains ...


Emended Classification Of Xanthomonad Pathogens On Citrus, Norman W. Schaad, Elena Postnikova, George Lacy, Aaron Sechler, Irina V. Agarkova, Paul E. Stromberg, Verlyn K. Stromberg, Anne K. Vidaver Oct 2006

Emended Classification Of Xanthomonad Pathogens On Citrus, Norman W. Schaad, Elena Postnikova, George Lacy, Aaron Sechler, Irina V. Agarkova, Paul E. Stromberg, Verlyn K. Stromberg, Anne K. Vidaver

Papers in Plant Pathology

In the paper by Schaad et al. [24] on reclassification of several xanthomonads, nomenclatural errors were made. The name Xanthomonas smithii subsp. citri proposed for the former taxon X. campestris pv. citri ( = X. axonopodis pv. citri) is illegitimate. Following the reinstatement of X. citri (ex Hasse 1915) Gabriel et al. [9] as a validly published name, Young et al. [34] wrote that the reinstatement of this epithet was based on a description that was inadequate in terms of modern practice for the purpose of formal classification. This report was subsequently summarized by the International Committee on the Systematics of Bacteria ...


Transcriptome Analysis Of Aspergillus Nidulans Exposed To Camptothecin-Induced Dna Damage, Iran Malazavi, Marcela Savoldi, Sonia Marla Zingaretti Di Mauro, Carlos Frederico Martins Menck, Steven D. Harris, Maria Helena De Souza Goldman, Gustavo Henrique Goldman Oct 2006

Transcriptome Analysis Of Aspergillus Nidulans Exposed To Camptothecin-Induced Dna Damage, Iran Malazavi, Marcela Savoldi, Sonia Marla Zingaretti Di Mauro, Carlos Frederico Martins Menck, Steven D. Harris, Maria Helena De Souza Goldman, Gustavo Henrique Goldman

Papers in Plant Pathology

We have used an Aspergillus nidulans macroarray carrying sequences of 2,787 genes from this fungus to monitor gene expression of both wild-type and uvsBATR (the homologue of the ATR gene) deletion mutant strains in a time course exposure to camptothecin (CPT). The results revealed a total of 1,512 and 1,700 genes in the wild-type and uvsBATR deletion mutant strains that displayed a statistically significant difference at at least one experimental time point. We characterized six genes that have increased mRNA expression in the presence of CPT in the wild-type strain relative to the uvsBATR ...


Dna Molecules And Polypeptides Of Pseudomonas Syringae Hrp Pathogenicity Island And Their Uses: U.S. Patent No. Us 7,102,059 B2, Alan Collmer, James R. Alfano, Amy O. Charkowski Sep 2006

Dna Molecules And Polypeptides Of Pseudomonas Syringae Hrp Pathogenicity Island And Their Uses: U.S. Patent No. Us 7,102,059 B2, Alan Collmer, James R. Alfano, Amy O. Charkowski

Papers in Plant Pathology

One aspect of the present invention relates to isolated nucleic acid molecules (i) encoding proteins or polypeptides of Pseudomonas CEL and EEL genomic regions, (ii) nucleic acid molecules which hybridize thereto under stringent conditions, or (iii) nucleic acid molecules that include a nucleotide sequence which is complementary to the nucleic acid molecules of (i) and (ii). Expression vectors, host cells, and transgenic plants which include the DNA molecules of the present invention are also disclosed. Another aspect relates to the isolated proteins or polypeptides and compositions containing the same. The nucleic acid molecules and proteins of the present invention can ...


Inducible Yeast System For Viral Rna Recombination Reveals Requirement For An Rna Replication Signal On Both Parental Rnas, Hernan Garcia-Ruiz, Paul Ahlquist Sep 2006

Inducible Yeast System For Viral Rna Recombination Reveals Requirement For An Rna Replication Signal On Both Parental Rnas, Hernan Garcia-Ruiz, Paul Ahlquist

Papers in Plant Pathology

To facilitate RNA recombination studies, we tested whether Saccharomyces cerevisiae, which supports brome mosaic virus (BMV) replication, also supports BMV RNA recombination. Yeast strains expressing BMV RNA replication proteins 1a and 2apol were engineered to transiently coexpress two independently inducible, overlapping, nonreplicating derivatives of BMV genomic RNA3. B33' lacked the coat protein gene and negative-strand RNA promoter. B35' lacked the positive-strand RNA promoter and had the coat gene replaced by the selectable URA3 gene. After 12 to 72 h of induction, B33' and B35' transcription was repressed and Ura+ yeast cells were selected. All Ura+ cells contained recombinant RNA3 ...


Cloning Of Nt.Cviqii Nicking Endonuclease And Its Cognate Methyltransferase: M.Cviqii Methylates Ag Sequence, Siu-Hong Chan, Zhenyu Zhu, David Dunigan, James L. Van Etten, Shuang-Yong Xu Sep 2006

Cloning Of Nt.Cviqii Nicking Endonuclease And Its Cognate Methyltransferase: M.Cviqii Methylates Ag Sequence, Siu-Hong Chan, Zhenyu Zhu, David Dunigan, James L. Van Etten, Shuang-Yong Xu

Papers in Plant Pathology

Chlorella virus NY-2A has a large, highly methylated dsDNA genome (45% of the cytosines are 5-methylcytosine and 37% of the adenines are N6-methyladenine). Here, we report the cloning, expression, and characterization of the NY-2A-encoded CviQII nicking-modification (N-M) system. The nicking endonuclease, Nt.CviQII, recognizes R ↓ AG (R = A or G, ↓ indicating cleavage site) sequences and cleaves the phosphodiester bond 5′ to the adenosine. Because of the difficulty in cloning and expressing the wild-type Nt.CviQII, C-terminal truncation mutants were generated and full-length Nt.CviQII was reconstructed by intein-mediated peptide ligation. The truncation mutants and the reconstructed full-length Nt ...


Nested Deletion Analysis Of Wheat Streak Mosaic Virus Hc-Pro: Mapping Of Domains Affecting Polyprotein Processing And Eriophyid Mite Transmission, Drake C. Stenger, Gary L. Hein, Roy C. French Jun 2006

Nested Deletion Analysis Of Wheat Streak Mosaic Virus Hc-Pro: Mapping Of Domains Affecting Polyprotein Processing And Eriophyid Mite Transmission, Drake C. Stenger, Gary L. Hein, Roy C. French

Papers in Plant Pathology

A series of in-frame and nested deletion mutations which progressively removed 5′-proximal sequences of the Wheat streak mosaic virus (WSMV) HC-Pro coding region (1152 nucleotides) was constructed and evaluated for pathogenicity to wheat. WSMV HC-Pro mutants with 5′- proximal deletions of 12 to 720 nucleotides systemically infected wheat. Boundary sequences flanking the deletions were stable and unaltered by passage through plants for all deletion mutants except HCD12 (lacking HC-Pro codons 3–6) that exhibited strong bias for G to A substitution at nucleotide 1190 in HC-Pro codon 2 (aspartic acid to asparagine). HC-Pro mutants with 5′-proximal deletions of ...


Functional Characterization Of Aspergillus Nidulans Homologues Of Saccharomyces Cerevisiae Spa2 And Bud6, Aleksandra Virag, Steven D. Harris Jun 2006

Functional Characterization Of Aspergillus Nidulans Homologues Of Saccharomyces Cerevisiae Spa2 And Bud6, Aleksandra Virag, Steven D. Harris

Papers in Plant Pathology

The importance of polarized growth for fungi has elicited significant effort directed at better understanding underlying mechanisms of polarization, with a focus on yeast systems. At sites of tip growth, multiple protein complexes assemble and coordinate to ensure that incoming building material reaches the appropriate destination sites, and polarized growth is maintained. One of these complexes is the polarisome that consists of Spa2, Bud6, Pea2, and Bni1 in Saccharomyces cerevisiae. Filamentous hyphae differ in their development and life style from yeasts and likely regulate polarized growth in a different way. This is expected to reflect on the composition and presence ...


An Assessment Model For Rating High-Threat Crop Pathogens, N. W. Schaad, J. Abrams, L. V. Madden, R. D. Frederick, D. G. Luster, V. D. Damsteegt, A. K. Vidaver May 2006

An Assessment Model For Rating High-Threat Crop Pathogens, N. W. Schaad, J. Abrams, L. V. Madden, R. D. Frederick, D. G. Luster, V. D. Damsteegt, A. K. Vidaver

Papers in Plant Pathology

Natural, accidental, and deliberate introductions of nonindigenous crop pathogens have become increasingly recognized as threats to the U.S. economy. Given the large number of pathogens that could be introduced, development of rapid detection methods and control strategies for every potential agent would be extremely difficult and costly. Thus, to ensure the most effective direction of resources a list of high-threat pathogens is needed. We address development of a pathogen threat assessment model based on the analytic hierarchy process (AHP) that can be applied worldwide, using the United States as an illustrative example. Previously, the AHP has been shown to ...


New Outbreaks Of Bacterial Wilt Of Dry Bean In Nebraska Observed From Field Infections, R. M. Harveson, H. F. Schwartz, A. K. Vidaver, Patricia A. Lambrecht, K. L. Otto May 2006

New Outbreaks Of Bacterial Wilt Of Dry Bean In Nebraska Observed From Field Infections, R. M. Harveson, H. F. Schwartz, A. K. Vidaver, Patricia A. Lambrecht, K. L. Otto

Papers in Plant Pathology

Bacterial wilt caused by Curtobacterium flaccumfaciens pv. flaccumfaciens was one of the more problematic diseases of dry bean (Phaseolus vulgaris L.) throughout the irrigated High Plains (Colorado, Nebraska, and Wyoming) in the 1960s and early 1970s, but has not been observed since that time. However, in August of 2003, plants exhibiting wilting and irregular, interveinal necrotic foliar lesions surrounded by a bright yellow border were found in three dry bean fields (market class Great Northern) in Scotts Bluff County, Nebraska. During 2004, plants exhibiting identical symptoms were additionally found occurring in more than 40 dry bean fields in western Nebraska ...


Association Of Plant Color And Pericarp Color With Colonization Of Grain By Members Of Fusarium And Alternaria In Near-Isogenic Sorghum Lines, Deanna L. Funnell, Jeffrey F. Pedersen Apr 2006

Association Of Plant Color And Pericarp Color With Colonization Of Grain By Members Of Fusarium And Alternaria In Near-Isogenic Sorghum Lines, Deanna L. Funnell, Jeffrey F. Pedersen

Papers in Plant Pathology

White sorghum (Sorghum bicolor) grain from tan plants is more desirable for human or animal consumption. Colonization by Fusarium and Alternaria spp. was assessed for near-isogenic lines differing in wound response (purple or tan) and pericarp color (red or white) in field-grown grain and in greenhouse-grown plants. Seeds were screened on a semi-selective medium for Alternaria and Fusarium. Significantly fewer fungal colonies were obtained from tan plants with white seed, and fewer numbers of Alternaria colonies were obtained from white seed, regardless of plant color, from an irrigated field, while there were no differences in fungal composition of seeds grown ...


Phycodnaviruses: A Peek At Genetic Diversity, David Dunigan, Lisa A. Fitzgerald, James L. Van Etten Apr 2006

Phycodnaviruses: A Peek At Genetic Diversity, David Dunigan, Lisa A. Fitzgerald, James L. Van Etten

Papers in Plant Pathology

The family Phycodnaviridae encompasses a diverse collection of large icosahedral, dsDNA viruses infecting algae. These viruses have genomes ranging from 160 to 560 kb. The family consists of six genera based initially on host range and supported by sequence comparisons. The family is monophyletic with branches for each genus, but the phycodnaviruses have evolutionary roots that connect with several other families of large DNA viruses, referred to as the nucleocytoplasmic large DNA viruses (NCLDV). The genomes of members in three genera in the Phycodnaviridae have recently been sequenced and the purpose of this manuscript is to summarize these data. The ...


Potassium Ion Channels Of Chlorella Viruses Cause Rapid Depolarization Of Host Cells During Infection, Florian Frohns, Anja Kasmann, Detlef Kramer, Britta Schafer, Mario Mehmel, Ming Kang, James L. Van Etten, Sabrina Gazzarrini, Ana Morino, Gerhard Thiel Mar 2006

Potassium Ion Channels Of Chlorella Viruses Cause Rapid Depolarization Of Host Cells During Infection, Florian Frohns, Anja Kasmann, Detlef Kramer, Britta Schafer, Mario Mehmel, Ming Kang, James L. Van Etten, Sabrina Gazzarrini, Ana Morino, Gerhard Thiel

Papers in Plant Pathology

revious studies have established that chlorella viruses encode K+ channels with different structural and functional properties. In the current study, we exploit the different sensitivities of these channels to Cs+ to determine if the membrane depolarization observed during virus infection is caused by the activities of these channels. Infection of Chlorella NC64A with four viruses caused rapid membrane depolarization of similar amplitudes, but with different kinetics. Depolarization was fastest after infection with virus SC-1A (half time [t1/2], about 9 min) and slowest with virus NY-2A (t1/2, about 12 min). Cs+ inhibited membrane depolarization only in viruses ...


Reaction Of Sorghum Lines Genetically Modified For Reduced Lignin Content To Infection By Fusarium And Alternaria Spp., Deanna L. Funnell, Jeffrey F. Pedersen Mar 2006

Reaction Of Sorghum Lines Genetically Modified For Reduced Lignin Content To Infection By Fusarium And Alternaria Spp., Deanna L. Funnell, Jeffrey F. Pedersen

Papers in Plant Pathology

Two genes conferring the brown midrib (bmr) trait had been backcrossed into six elite sorghum lines, resulting in reduced lignin in the bmr lines when compared with the wild-type parent. Seed and leaf tissue from field-grown plants, planted at two locations, were screened for Alternariu spp. and Fusarium spp. on semi-selective media. The results suggest that bmr lines do not have increased susceptibility to colonization by Alternariu spp. However, significantly fewer colonies of Fusarium spp., including Fusarium moniliforme, were recovered from seed of reduced lignin lines from two genetic backgrounds. That the bmr trait in some genetic backgrounds might enable ...


Polarity In Plants - Annual Plant Reviews, Volume 12, Steven D. Harris Mar 2006

Polarity In Plants - Annual Plant Reviews, Volume 12, Steven D. Harris

Papers in Plant Pathology

Polarity is a fundamental property of all cells. The molecular mechanisms that underlies the establishment and maintenance of cellular polarity have been intensively studied in animal cells and yeast-like fungi. These studies reveal an emerging general principle whereby positional information is relayed to the cytoskeleton and other morphogenetic functions by conserved signaling pathways. Comparatively less attention has been directed toward the molecular basis of polarized growth in plant cells and tissues. This volume, Polarity in Plants, provides a comprehensive review of the topic that should satisfy both hardcore aficionados of plant cell and developmental biology as well as curious investigators ...


Bacillus Species Nrrl B-30212 For Reducing Fusarium Head Blight In Cereals, David A. Schisler, Naseem L. Khan, Michael J. Boehm Feb 2006

Bacillus Species Nrrl B-30212 For Reducing Fusarium Head Blight In Cereals, David A. Schisler, Naseem L. Khan, Michael J. Boehm

Papers in Plant Pathology

Four yeasts (NRRL Y-30213, NRRL Y-30214, NRRL Y-30215, and NRRL Y-30216) and 1 bacterium (NRRL B-30212) have been identified as being superior antagonists capable of suppressing Fusarium head blight (head scab) in cereals, particularly in wheat and barley. Fusarium head blight is primarily caused by the fungus Gibberella zeae (anamorph=Fusarium graminearum).


Farnesol-Induced Apoptosis In Aspergillus Nidulans Reveals A Possible Mechanism For Antagonistic Interactions Between Fungi, Camile P. Semighini, Jacob M. Hornby, Raluca Dumitru, Kenneth W. Nickerson, Steven D. Harris Feb 2006

Farnesol-Induced Apoptosis In Aspergillus Nidulans Reveals A Possible Mechanism For Antagonistic Interactions Between Fungi, Camile P. Semighini, Jacob M. Hornby, Raluca Dumitru, Kenneth W. Nickerson, Steven D. Harris

Papers in Plant Pathology

The dimorphic fungus Candida albicans secretes farnesol, which acts as a quorum-sensing molecule and prevents the yeast to mycelium conversion. In this study we examined the effect of farnesol in the filamentous fungus Aspergillus nidulans. We show that externally added farnesol has no effect on hyphal morphogenesis; instead, it triggers morphological features characteristic of apoptosis. Additional experiments suggest that mitochondria and reactive oxygen species (ROS) participate in farnesol-induced apoptosis. Moreover, the effects of farnesol appear to be mediated by the FadA heterotrimeric G protein complex. Because A. nidulans does not secrete detectable amounts of farnesol, we propose that it responds ...


Registration Of Seven Forage Sorghum Genetic Stocks Near-Isogenic For The Brown Midrib Genes Bmr-6 And Bmr-12, Jeffrey F. Pedersen, Deanna L. Funnell, John J. Toy, A.L. Oliver, R.J. Grant Jan 2006

Registration Of Seven Forage Sorghum Genetic Stocks Near-Isogenic For The Brown Midrib Genes Bmr-6 And Bmr-12, Jeffrey F. Pedersen, Deanna L. Funnell, John J. Toy, A.L. Oliver, R.J. Grant

Papers in Plant Pathology

Seven forage sorghum [Sorghum bicolor (L.) Moench] genetic stocks, N592 to N598, (Reg. no. GS-121–GS-127, PI639702– PI639708) near-isogenic to their wild-type counterparts for the brown midrib genes bmr-6 and bmr-12 were developed jointly by the USDA-ARS and the Agricultural Research Division, Institute of Agriculture and Natural Resources, University of Nebraska, and were released in January 2005.


Registration Of Twelve Grain Sorghum Genetic Stocks Near-Isogenic For The Brown Midrib Genes Bmr-6 And Bmr-12, Jeffrey F. Pedersen, Deanna L. Funnell, John J. Toy, A.L. Oliver, R.J. Grant Jan 2006

Registration Of Twelve Grain Sorghum Genetic Stocks Near-Isogenic For The Brown Midrib Genes Bmr-6 And Bmr-12, Jeffrey F. Pedersen, Deanna L. Funnell, John J. Toy, A.L. Oliver, R.J. Grant

Papers in Plant Pathology

Twelve grain sorghum [Sorghum bicolor (L.) Moench] genetic stocks, N599 to N610, (Reg. no. GS-128–GS-139, PI 639709–PI 639720) near-isogenic to their wild-type counterparts for the brown midrib genes bmr-6 and bmr-12 were developed jointly by the USDA-ARS, and the Agricultural Research Division, Institute of Agriculture and Natural Resources, University of Nebraska, and were released in May 2005.


Registration Of ‘Atlas Bmr-12’ Forage Sorghum, Jeffrey F. Pedersen, Deanna L. Funnell, John J. Toy, A.L. Oliver, R.J. Grant Jan 2006

Registration Of ‘Atlas Bmr-12’ Forage Sorghum, Jeffrey F. Pedersen, Deanna L. Funnell, John J. Toy, A.L. Oliver, R.J. Grant

Papers in Plant Pathology

Atlas bmr-12 forage sorghum [Sorghum bicolor (L.)Moench] (Reg, no. CV-136, PI 636763) was developed jointly by the USDA, ARS and the Agricultural Research Division, Institute of Agriculture and Natural Resources, University of Nebraska, and was released in January 2005.


Bioinformatics-Enabled Identification Of The Hrpl Regulon And Type Iii Secretion System Effector Proteins Of Pseudomonas Syringae Pv. Phaseolicola 1448a, Monica Vencato, Fang Tian, James R. Alfano, C. Robin Buell, Samuel Cartinhour, Genevieve A. Declerck, David S. Guttman, John Stavrinides, Vinita Joardar, Magdalen Lindeberg, Philip A. Bronstein, John W. Mansfield, Christopher R. Myers, Alan Collmer, David J. Schneider Jan 2006

Bioinformatics-Enabled Identification Of The Hrpl Regulon And Type Iii Secretion System Effector Proteins Of Pseudomonas Syringae Pv. Phaseolicola 1448a, Monica Vencato, Fang Tian, James R. Alfano, C. Robin Buell, Samuel Cartinhour, Genevieve A. Declerck, David S. Guttman, John Stavrinides, Vinita Joardar, Magdalen Lindeberg, Philip A. Bronstein, John W. Mansfield, Christopher R. Myers, Alan Collmer, David J. Schneider

Papers in Plant Pathology

The ability of Pseudomonas syringae pv. phaseolicola to cause halo blight of bean is dependent on its ability to translocate effector proteins into host cells via the hypersensitive response and pathogenicity (Hrp) type III secretion system (T3SS). To identify genes encoding type III effectors and other potential virulence factors that are regulated by the HrpL alternative sigma factor, we used a hidden Markov model, weight matrix model, and type III targeting-associated patterns to search the genome of P. syringae pv. phaseolicola 1448A, which recently was sequenced to completion. We identified 44 high-probability putative Hrp promoters upstream of genes encoding the ...


Carbon-To-Nitrogen Ratio And Carbon Loading Of Production Media Influence Freeze-Drying Survival And Biocontrol Efficacy Of Cryptococcus Nodaensis Oh 182.9, Shouan Zhang, David A. Schisler, Michael J. Boehm, Patricia J. Slininger Jan 2006

Carbon-To-Nitrogen Ratio And Carbon Loading Of Production Media Influence Freeze-Drying Survival And Biocontrol Efficacy Of Cryptococcus Nodaensis Oh 182.9, Shouan Zhang, David A. Schisler, Michael J. Boehm, Patricia J. Slininger

Papers in Plant Pathology

Fusarium head blight (FHB), caused by Gibberella zeae, is a devastating disease of wheat worldwide. Cryptococcus nodaensis OH 182.9 is an effective biocontrol agent for this disease. Development of a dried product of OH 182.9 would have potential advantages of ease of handling, favorable economics, and acceptance by end users. Isolate OH 182.9 was grown for 48 and 72 h in semi-defined complete liquid (SDCL) medium with carbon-to-nitrogen (C/N) ratios of 6.5:1, 9:1, 11:1, 15:1, and 30:1, and in SDCL C/N 30:1 media with varied carbon loadings of ...


Regulation Of Hyphal Morphogenesis And The Dna Damage Response By The Aspergillus Nidulans Atm Homolog Atma, Iran Malavazi, Camile P. Semighini, Marcia Regina Von Zeska Kress, Steven D. Harris, Gustavo H. Goldman Jan 2006

Regulation Of Hyphal Morphogenesis And The Dna Damage Response By The Aspergillus Nidulans Atm Homolog Atma, Iran Malavazi, Camile P. Semighini, Marcia Regina Von Zeska Kress, Steven D. Harris, Gustavo H. Goldman

Papers in Plant Pathology

Ataxia telangiectasia (A-T) is an inherited disorder characterized by progressive loss of motor function and susceptibility to cancer. The most prominent clinical feature observed in A-T patients is the degeneration of Purkinje motor neurons. Numerous studies have emphasized the role of the affected gene product, ATM, in the regulation of the DNA damage response. However, in Purkinje cells, the bulk of ATM localizes to the cytoplasm and may play a role in vesicle trafficking. The nature of this function, and its involvement in the pathology underlying A-T, remain unknown. Here we characterize the homolog of ATM (AtmA) in the filamentous ...


First Report Of Sudden Death Syndrome Of Soybean Caused By Fusarium Solani F. Sp. Glycines In Nebraska, A. D. Ziems, L. J. Giesler, G. Y. Yuen Jan 2006

First Report Of Sudden Death Syndrome Of Soybean Caused By Fusarium Solani F. Sp. Glycines In Nebraska, A. D. Ziems, L. J. Giesler, G. Y. Yuen

Papers in Plant Pathology

During August of 2004, soybean (Glycine max (L.) Merr.) plants exhibiting symptoms typical of sudden death syndrome (SDS) caused by Fusarium solani (Mart.) Sacc. f. sp. glycines (= Fusarium virguliforme Akoi, O'Donnell, Homma, & Lattanzi) (1) were observed in Nemaha and Pierce counties in eastern Nebraska. Leaf symptoms ranged from small chlorotic spots to prominent interveinal necrosis on plants at R5-R6 growth stages. Taproots of symptomatic plants were plated on potato dextrose agar (PDA) amended with hymexazol, ampicillin, and rifampicin (HAR). Resulting fungal isolates grew slowly and developed masses of blue macroconidia, characteristic of F. solani f. sp. glycines. Sorghum seed ...


First Report Of Leaf Spot Of Smooth Bromegrass Caused By Pithomyces Chartarum In Nebraska, C. Eken, C. C. Jochum, G. Y. Yuen Jan 2006

First Report Of Leaf Spot Of Smooth Bromegrass Caused By Pithomyces Chartarum In Nebraska, C. Eken, C. C. Jochum, G. Y. Yuen

Papers in Plant Pathology

Smooth bromegrass (Bromus inermis Leyss.) is the most common perennial grass species cultivated for forage in North America. During late fall of 2004, smooth bromegrass plants in Lincoln, NE were observed to have brown lesions on leaf midveins that were several centimeters long. Symptomatic leaves were surface disinfested for 1 min in 2% NaOCl and incubated at 25°C on potato dextrose agar (PDA) and water agar. The fungus, Pithomyces chartarum (Berk. & Curt) Ellis, was isolated consistently and identified on the basis of morphological characteristics (1). Colonies were effused and black on PDA. Conidiophores measured 3.5 to 8 × 1 ...


A Position Paper On The Electronic Publication Of Nematode Taxonomic Manuscripts, Eyualem Abebe, James G. Baldwin, Byron Adams, Duane Hope, Scott Gardner, Robin Huettel, Peter Mullin, Thomas O. Powers, Jyotsna Sharma, Weimin Ye, William K. Thomas Jan 2006

A Position Paper On The Electronic Publication Of Nematode Taxonomic Manuscripts, Eyualem Abebe, James G. Baldwin, Byron Adams, Duane Hope, Scott Gardner, Robin Huettel, Peter Mullin, Thomas O. Powers, Jyotsna Sharma, Weimin Ye, William K. Thomas

Papers in Plant Pathology

Several nematode species have now attained ‘model organism’ status, yet there remain many niches in basic biological inquiry for which nematodes would be ideal model systems of study. However, furthering the model system approach is hindered by lack of information on nematode biodiversity. The shortage of taxonomic resources to inventory and characterize biodiversity hinders research programs in invasion biology, ecosystem functioning, conservation biology, and many others. The disproportion between numbers of species to be described and numbers of available taxonomic specialists is greater for Nematoda than for any other metazoan phylum. A partial solution to the taxonomic impediment is the ...


Avenacin Production In Creeping Bentgrass (Agrostis Stolonifera) And Its Influence On The Host Range Of Gaeumannomyces Graminis, S. L. Thomas, P. Bonello, P. E. Lipps, Michael J. Boehm Jan 2006

Avenacin Production In Creeping Bentgrass (Agrostis Stolonifera) And Its Influence On The Host Range Of Gaeumannomyces Graminis, S. L. Thomas, P. Bonello, P. E. Lipps, Michael J. Boehm

Papers in Plant Pathology

Avenacinase activity has been shown to be a key factor determining the host range of Gaeumannomyces graminis on oats (Avena sativa). G. graminis var. avenae produces avenacinase, which detoxifies the oat root saponin avenacin, enabling it to infect oats. G. graminis var. tritici does not produce avenacinase and is unable to infect oats. G. graminis var. avenae is also reported to incite take-all patch on creeping bentgrass (Agrostis stolonifera). It is unknown whether creeping bentgrass produces avenacin and if the avenacin-avenacinase interaction influences G. graminis pathogenicity on creeping bentgrass. The root extracts of six creeping bentgrass cultivars were analyzed by ...


Fungicide Sensitivity Of Sclerotinia Homoeocarpa From Golf Courses In Ohio, Young-Ki Jo, Amy L. Niver, Joseph W. Rimelspach, Michael J. Boehm Jan 2006

Fungicide Sensitivity Of Sclerotinia Homoeocarpa From Golf Courses In Ohio, Young-Ki Jo, Amy L. Niver, Joseph W. Rimelspach, Michael J. Boehm

Papers in Plant Pathology

Managing dollar spot, the most common and chronic disease on intensively cultivated turfgrass, relies on the judicious use of fungicides. The heavy use of fungicides has led to the development of isolates of Sclerotinia homoeocarpa insensitive to several classes of fungicides, including benzimidazoles, demethylation-inhibitors, and dicarboximides. In vitro fungicide sensitivity assays using single discriminatory concentrations of thiophanate-methyl, propiconazole, and iprodione were developed in this study for evaluating field efficacy of these fungicides and the prevalence of fungicide insensitivity within S. homoeocarpa isolated from golf courses throughout Ohio. Discriminatory concentrations for these fungicides were determined to be: thiophanate-methyl = 1,000 μg ...