Life Sciences Commons^™

A Global-Temporal Analysis On Phytophthora Sojae Resistance-Gene Efficacy, Austin G. Mccoy, Richard R. Belanger, Carl A. Bradley, Daniel G. Cerritos-Garcia, Vinicius C. Garnica, Loren Giesler, Pablo E. Grijalba, Eduardo Guillin, Maria A. Henriquez, Yong Min Kim, Dean K. Malvick, Rashelle L. Matthiesen, Santiago X. Mideros, Zachary A. Noel, Alison E. Robertson, Mitchell G. Roth, Clarice L. Schmidt, Damon L. Smith, Adam H. Sparks, Darcy E.P. Telenko, Vanessa Tremblay, Owen Wally, Martin I. Chilvers

Department of Plant Pathology: Faculty Publications

Plant disease resistance genes are widely used in agriculture to reduce disease outbreaks and epidemics and ensure global food security. In soybean, Rps (Resistance to Phytophthora sojae) genes are used to manage Phytophthora sojae, a major oomycete pathogen that causes Phytophthora stem and root rot (PRR) worldwide. This study aims to identify temporal changes in P. sojae pathotype complexity, diversity, and Rps gene efficacy. Pathotype data was collected from 5121 isolates of P. sojae, derived from 29 surveys conducted between 1990 and 2019 across the United States, Argentina, Canada, and China. This systematic review shows a loss of efficacy of …

The Pseudomonas Syringae Pv. Tomato Dc3000 Effector Hopd1 Interferes With Cellular Dynamics Associated With The Function Of The Plant Immune Protein Atnhr2b, Luis Francisco Marín-Ponce, Catalina Rodríguez-Puerto, Perla Rocha-Loyola, Clemencia M. Rojas

Department of Plant Pathology: Faculty Publications

The plant pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes disease in tomato, in the model plant Arabidopsis thaliana, and conditionally in Nicotiana benthamiana. The pathogenicity of Pst DC3000 is mostly due to bacterial virulence proteins, known as effectors, that are translocated into the plant cytoplasm through the type III secretion system (T3SS). Bacterial type III secreted effectors (T3SEs) target plants physiological processes and suppress defense responses to enable and support bacterial proliferation. The Pst DC3000 T3SE HopD1 interferes with plant defense responses by targeting the transcription factor NTL9. This work shows that HopD1 also targets …

Dynamic Reconfiguration Of Switchgrass Proteomes In Response To Rust (Puccinia Novopanici) Infection, Nathan A. Palmer, Sophie Alvarez, Michael J. Naldrett, Anthony Muhle, Gautam Sarath, Serge J. Edmé, Satyanarayana Tatineni, Robert B. Mitchell, Gary Yuen

Department of Plant Pathology: Faculty Publications

Switchgrass (Panicum virgatum L.) can be infected by the rust pathogen (Puccinia novopanici) and results in lowering biomass yields and quality. Label-free quantitative proteomics was conducted on leaf extracts harvested from non-infected and infected plants from a susceptible cultivar (Summer) at 7, 11, and 18 days after inoculation (DAI) to follow the progression of disease and evaluate any plant compensatory mechanisms to infection. Some pustules were evident at 7 DAI, and their numbers increased with time. However, fungal DNA loads did not appreciably change over the course of this experiment in the infected plants. In total, 3830 …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard A. Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

P3 And Nia-Pro Of Turnip Mosaic Virus Are Independent Elicitors Of Superinfection Exclusion, Haritha Nunna, Feng Qu, Satyanarayana Tatineni

Department of Plant Pathology: Faculty Publications

Superinfection exclusion (SIE) is an antagonistic interaction between identical or closely related viruses in host cells. Previous studies by us and others led to the hypothesis that SIE was elicited by one or more proteins encoded in the genomes of primary viruses. Here, we tested this hypothesis using Turnip mosaic virus (TuMV), a member of the genus Potyvirus of the family Potyviridae, with significant economic consequences. To this end, individual TuMV-encoded proteins were transiently expressed in the cells of Nicotiana benthamiana leaves, followed by challenging them with a modified TuMV expressing the green fluorescent protein (TuMV-GFP). Three days after …

P3 And Nia-Pro Of Turnip Mosaic Virus Are Independent Elicitors Of Superinfection Exclusion, Haritha Nunna, Feng Qu, Satyanarayana Tatineni

Department of Plant Pathology: Faculty Publications

Superinfection exclusion (SIE) is an antagonistic interaction between identical or closely related viruses in host cells. Previous studies by us and others led to the hypothesis that SIE was elicited by one or more proteins encoded in the genomes of primary viruses. Here, we tested this hypothesis using Turnip mosaic virus (TuMV), a member of the genus Potyvirus of the family Potyviridae, with significant economic consequences. To this end, individual TuMV-encoded proteins were transiently expressed in the cells of Nicotiana benthamiana leaves, followed by challenging them with a modified TuMV expressing the green fluorescent protein (TuMV-GFP). Three days after …

Induction And Suppression Of Gene Silencing In Plants By Nonviral Microbes, Eric Parperides, Kaoutar El Mounadi, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Gene silencing is a conserved mechanism in eukaryotes that dynamically regulates gene expression. In plants, gene silencing is critical for development and for maintenance of genome integrity. Additionally, it is a critical component of antiviral defence in plants, nematodes, insects, and fungi. To overcome gene silencing, viruses encode effectors that suppress gene silencing. A growing body of evidence shows that gene silencing and suppression of silencing are also used by plants during their interaction with nonviral pathogens such as fungi, oomycetes, and bacteria. Plant–pathogen interactions involve trans-kingdom movement of small RNAs into the pathogens to alter the function of genes …

Induction And Suppression Of Gene Silencing In Plants By Nonviral Microbes, Eric Parperides, Kaoutar El Mounadi, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Gene silencing is a conserved mechanism in eukaryotes that dynamically regulates gene expression. In plants, gene silencing is critical for development and for maintenance of genome integrity. Additionally, it is a critical component of antiviral defence in plants, nematodes, insects, and fungi. To overcome gene silencing, viruses encode effectors that suppress gene silencing. A growing body of evidence shows that gene silencing and suppression of silencing are also used by plants during their interaction with nonviral pathogens such as fungi, oomycetes, and bacteria. Plant–pathogen interactions involve trans-kingdom movement of small RNAs into the pathogens to alter the function of genes …

Nationwide Assessment Of Leadership Development For Graduate Students In The Agricultural Plant Sciences, Karen Ferreira Da Silva, Ella Burnham, Joe Louis, Douglas Golick, Sydney E. Everhart

Department of Plant Pathology: Faculty Publications

Leadership development is a universally important goal across the agricultural plant science disciplines. Although previous studies have identified a need for leadership skills, less is known about leadership skill development in graduate programs. To address this, we constructed a mixed-method study to identify the most significant graduate school leadership experiences of scientists in the agricultural plant science disciplines. The survey was deployed to 6,728 people in the U.S. and received 1,086 responses (16.1% response rate). The majority of respondents reported that they were from one of the major agricultural states and employed at one of the agricultural plant science related …

Plant Viruses Of Agricultural Importance: Current And Future Perspectives Of Virus Disease Management Strategies, Satyanarayana Tatineni, Gary Hein

Department of Plant Pathology: Faculty Publications

Plant viruses cause significant losses in agricultural crops worldwide, affecting the yield and quality of agricultural products. The emergence of novel viruses or variants through genetic evolution and spillover from reservoir host species, changes in agricultural practices, mixed infections with disease synergism, and impacts from global warming pose continuous challenges for the management of epidemics resulting from emerging plant virus diseases. This review describes some of the most devastating virus diseases plus select virus diseases with regional importance in agriculturally important crops that have caused significant yield losses. The lack of curative measures for plant virus infections prompts the use …

Population Genomics Provide Insights Into The Global Genetic Structure Of Colletotrichum Graminicola, The Causal Agent Of Maize Anthracnose, Flávia Rogério, Riccardo Baroncelli, Francisco Borja Cuevas-Fernández, Sioly Becerra, Joanne Crouch, Wagner Bettiol, M. Andrea Azcárate-Peril, Martha Malapi-Wight, Veronique Ortega, Javier Betran, Albert Tenuta, José S. Dambolena, Paul D. Esker, Pedro Revilla, Tamra A. Jackson-Ziems, Jürg Hiltbrunner, Gary Munkvold, Ivica Buhiniček, José L. Vicente-Villardón, Serenella A. Sukno, Michael R. Thon

Department of Plant Pathology: Faculty Publications

Understanding the genetic diversity and mechanisms underlying genetic variation in pathogen populations is crucial to the development of effective control strategies. We investigated the genetic diversity and reproductive biology of Colletotrichum graminicola isolates which infect maize by sequencing the genomes of 108 isolates collected from 14 countries using restriction site-associated DNA sequencing (RAD-seq) and wholegenome sequencing (WGS). Clustering analyses based on single-nucleotide polymorphisms revealed three genetic groups delimited by continental origin, compatible with short-dispersal of the pathogen and geographic subdivision. Intra- and intercontinental migration was observed between Europe and South America, likely associated with the movement of contaminated germplasm. Low …

6k1, Nia-Vpg, Nia-Pro, And Cp Ofwheat Streak Mosaic Virus Are Collective Determinants Of Wheat Streak Mosaic Disease In Wheat, Satyanarayana Tatineni, Jeffrey Alexander, Haritha Nunna

Department of Plant Pathology: Faculty Publications

Wheat streak mosaic virus (WSMV; genus Tritimovirus, family Potyviridae) is the causal agent of the most economically important wheat streak mosaic disease of wheat (Triticum aestivum) in the Great Plains region of theUnited States.WSMVdeterminants responsible forwheat streak mosaic disease in wheat are unknown. Triticum mosaic virus (TriMV), a wheatinfecting virus,was used as an expression vector for the transient expression of each of the WSMV-encoded cistrons in wheat. WSMV-encoded 6K1, NIa-VPg, NIa-Pro, and CP cistrons in TriMV elicited symptoms specific to different stages of wheat streak mosaic disease without significantly affecting the genomic RNA accumulation. WSMV 6K1 …

6k1, Nia-Vpg, Nia-Pro, And Cp Ofwheat Streak Mosaic Virus Are Collective Determinants Of Wheat Streak Mosaic Disease In Wheat, Satyanarayana Tatineni, Jeffrey Alexander, Haritha Nunna

Department of Plant Pathology: Faculty Publications

Wheat streak mosaic virus (WSMV; genus Tritimovirus, family Potyviridae) is the causal agent of the most economically important wheat streak mosaic disease of wheat (Triticum aestivum) in the Great Plains region of theUnited States.WSMVdeterminants responsible forwheat streak mosaic disease in wheat are unknown. Triticum mosaic virus (TriMV), a wheatinfecting virus,was used as an expression vector for the transient expression of each of the WSMV-encoded cistrons in wheat. WSMV-encoded 6K1, NIa-VPg, NIa-Pro, and CP cistrons in TriMV elicited symptoms specific to different stages of wheat streak mosaic disease without significantly affecting the genomic RNA accumulation. WSMV 6K1 …

Near-Atomic, Non-Icosahedrally Averaged Structure Of Giant Virus Paramecium Bursaria Chlorella Virus 1, Qianqian Shao, Irina V. Agarkova, Eric A. Noel, David D. Dunigan, Yunshu Liu, Aohan Wang, Mingcheng Guo, Linlin Xie, Xinyue Zhao, Michael G. Rossmann, James L. Van Etten, Thomas Klose, Qianglin Fang

Department of Plant Pathology: Faculty Publications

Giant viruses are a large group of viruses that infect many eukaryotes. Although components that do not obey the overall icosahedral symmetry of their capsids have been observed and found to play critical roles in the viral life cycles, identities and high-resolution structures of these components remain unknown. Here, by determining a near-atomic-resolution, five-fold averaged structure of Parameciumbursaria chlorella virus 1, we unexpectedly found the viral capsid possesses up to five major capsid protein variants and a penton protein variant. These variants create varied capsidmicroenvironments for the associations of fibers, a vesicle, and previously unresolved minor capsid proteins. Our structure …

Clavibacter Nebraskensis Causing Goss's Wilt Of Maize: Five Decades Of Detaining The Enemy In The New World, Ebrahim Osdaghi, Alison E. Robertson, Tamra Jackson-Ziems, Hamid Abachi, Xiang Li, Robert M. Harveson

Department of Plant Pathology: Faculty Publications

Goss's bacterial wilt and leaf blight of maize (Zea mays) caused by the gram-positive coryneform bacterium Clavibacter nebraskensis is an economically important disease in North America. C. nebraskensis is included within the high-risk list of quarantine pathogens by several plant protection organizations (EPPO code: CORBMI), hence it is under strict quarantine control around the world. The causal agent was reported for the first time on maize in Nebraska (USA) in 1969. After an outbreak during the 1970s, prevalence of the disease decreased in the 1980s to the early 2000s, before the disease resurged causing a serious threat to …

Clavibacter Nebraskensis Causing Goss's Wilt Of Maize: Five Decades Of Detaining The Enemy In The New World, Ebrahim Osdaghi, Alison E. Robertson, Tamra Jackson-Ziems, Hamid Abachi, Xiang Li, Robert M. Harveson

Department of Plant Pathology: Faculty Publications

Goss's bacterial wilt and leaf blight of maize (Zea mays) caused by the gram-positive coryneform bacterium Clavibacter nebraskensis is an economically important disease in North America. C. nebraskensis is included within the high-risk list of quarantine pathogens by several plant protection organizations (EPPO code: CORBMI), hence it is under strict quarantine control around the world. The causal agent was reported for the first time on maize in Nebraska (USA) in 1969. After an outbreak during the 1970s, prevalence of the disease decreased in the 1980s to the early 2000s, before the disease resurged causing a serious threat to …

Clavibacter Nebraskensis Causing Goss's Wilt Of Maize: Five Decades Of Detaining The Enemy In The New World, Ebrahim Osdaghi, Alison E. Robertson, Tamra A. Jackson-Ziems, Hamid Abachi, Xiang Li, Robert M. Harveson

Department of Plant Pathology: Faculty Publications

Goss's bacterial wilt and leaf blight of maize (Zea mays) caused by the gram-positive coryneform bacterium Clavibacter nebraskensis is an economically important disease in North America. C. nebraskensis is included within the high-risk list of quarantine pathogens by several plant protection organizations (EPPO code: CORBMI), hence it is under strict quarantine control around the world. The causal agent was reported for the first time on maize in Nebraska (USA) in 1969. After an outbreak during the 1970s, prevalence of the disease decreased in the 1980s to the early 2000s, before the disease resurged causing a serious threat to maize production …

18s-Nemabase: Curated 18s Rrna Database Of Nematode Sequences, Kaitlin Gattoni, Eli M. S. Gendron, Rebeca Sandoval- Ruiz, Abigail Borgemeier, J. Parr Mcqueen, Rachel M. Shepherd, Dieter Slos, Tom Powers, Dorota L. Porazinska

Department of Plant Pathology: Faculty Publications

Nematodes are the most abundant and diverse animals on the planet but lack representation in biodiversity research. This presents a problem for studying nematode diversity, particularly when molecular tools (i.e., barcoding and metabarcoding) rely on well-populated and curated reference databases, which are absent for nematodes. To improve molecular identification and the assessment of nematode diversity, we created and curated an 18S rRNA database specific to nematodes (18S-NemaBase) using sequences sourced from the most recent publicly available 18S rRNA SILVA v138 database. As part of the curation process, taxonomic strings were standardized to contain a fixed number of taxonomic ranks relevant …

18s-Nemabase: Curated 18s Rrna Database Of Nematode Sequences, Kaitlin Gattoni, Eli M. S. Gendron, Rebeca Sandoval- Ruiz, Abigail Borgemeier, J. Parr Mcqueen, Rachel M. Shepherd, Dieter Slos, Tom Powers, Dorota L. Porazinska

Department of Plant Pathology: Faculty Publications

Nematodes are the most abundant and diverse animals on the planet but lack representation in biodiversity research. This presents a problem for studying nematode diversity, particularly when molecular tools (i.e., barcoding and metabarcoding) rely on well-populated and curated reference databases, which are absent for nematodes. To improve molecular identification and the assessment of nematode diversity, we created and curated an 18S rRNA database specific to nematodes (18S-NemaBase) using sequences sourced from the most recent publicly available 18S rRNA SILVA v138 database. As part of the curation process, taxonomic strings were standardized to contain a fixed number of taxonomic ranks relevant …

Plectus Of The Prairie: A Case Study Of Taxonomic Resolution From A Nematode Biodiversity Survey, Abigail Borgmeier, Kaitlin Gattoni, Timothy Harris, Rebecca Higgins, Peter Mullin, Dorota Porazinska, Kirsten S. Powers, David A. Wedin, Tom Powers

Department of Plant Pathology: Faculty Publications

Taxonomic resolution is a critical component of biodiversity assessments. In this case study, we examined a single taxon within a larger study of nematode diversity to evaluate the taxonomic resolution of different diversity assessment methods. The selected taxon was the microbial-feeding genus Plectus, a group considered to include multiple cosmopolitan species. The methods included a morphological evaluation by light microscopy, Sanger sequencing of PCR amplicons of COI and 18S gene regions, and 18S metabarcoding sequencing. The study sites were 15 remnant tallgrass prairie plots in eastern Nebraska. In the morphological analysis, we observed two basic morphotypes, a short-tailed form …

Two Magnaporthe Appressoria-Specific (Mas) Proteins, Momas3 And Momas5, Are Required For Suppressing Host Innate Immunity And Promoting Biotrophic Growth In Rice Cells, Ziwen Gong, Na Ning, Zhiqiang Li, Xin Xie, Richard Wilson, Wende Liu

Department of Plant Pathology: Faculty Publications

In the devastating rice blast fungus Magnaporthe oryzae, six Magnaporthe appressoria-specific (MAS) proteins are encoded by MoGAS1, MoGAS2 and MoMAS3–MoMAS6. MoGAS1 and MoGAS2 were previously characterized as M. oryzae virulence factors; however, the roles of the other four genes are unknown. Here, we found that, although the loss of any MAS gene did not affect appressorial formation or vegetative growth, ΔMomas3 and ΔMomas5 mutant strains (but not the others) were reduced in virulence on susceptible CO-39 rice seedlings. Focusing on ΔMomas3 and ΔMomas5 mutant strains, we found that they could penetrate …

Ecology And Diversity Of Culturable Fungal Species Associated With Soybean Seedling Diseases In The Midwestern United States, Mirian F. Pimentel, Ali Y. Srour, Amanda J. Warner, Jason P. Bond, Carl A. Bradley, John Rupe, Martin I. Chilvers, J. Alejandro Rojas, Janette L. Jacobs, Christopher R. Little, Alison E. Robertson, Loren J. Giesler, Dean Malvick, Kiersten Wise, Albert Tenuta, Ahmad M. Fakhoury

Department of Plant Pathology: Faculty Publications

Aims: To isolate and characterize fungi associated with diseased soybean seedlings in Midwestern soybean production fields and to determine the influence of environmental and edaphic factors on their incidence.

Methods and Results: Seedlings were collected from fields with seedling disease history in 2012 and 2013 for fungal isolation. Environmental and edaphic data associated with each field was collected. 3036 fungal isolates were obtained and assigned to 76 species. The most abundant genera recovered were Fusarium (73%) and Trichoderma (11.2%). Other genera included Mortierella, Clonostachys, Rhizoctonia, Alternaria, Mucor, Phoma, Macrophomina and Phomopsis. …

Improving Taxonomic Delimitation Of Fungal Species In The Age Of Genomics And Phenomics, Asjley Stengel, Kimberly M. Stanke, Amanda C. Quattrone, Joshua Herr

Department of Plant Pathology: Faculty Publications

Species concepts have long provided a source of debate among biologists. These lively debates have been important for reaching consensus on how to communicate across scientific disciplines and for advancing innovative strategies to study evolution, population biology, ecology, natural history, and disease epidemiology. Species concepts are also important for evaluating variability and diversity among communities, understanding biogeographical distributions, and identifying causal agents of disease across animal and plant hosts. While there have been many attempts to address the concept of species in the fungi, there are several concepts that have made taxonomic delimitation especially challenging. In this review we discuss …

The Astounding World Of Glycans From Giant Viruses, Anna Notaro, Chantal Abergel, Rosa Lanzetta, Todd L. Lowary, Antonio Molinaro, Michela Tonetti, James L. Van Etten, Cristina De Castro

Department of Plant Pathology: Faculty Publications

Viruses are a heterogeneous ensemble of entities, all sharing the need for a suitable host to replicate. They are extremely diverse, varying in morphology, size, nature, and complexity of their genomic content. Typically, viruses use host-encoded glycosyltransferases and glycosidases to add and remove sugar residues from their glycoproteins. Thus, the structure of the glycans on the viral proteins have, to date, typically been considered to mimick those of the host. However, the more recently discovered large and giant viruses differ from this paradigm. At least some of these viruses code for an (almost) autonomous glycosylation pathway. These viral genes include …

Improving Taxonomic Delimitation Of Fungal Species In The Age Of Genomics And Phenomics, Ashley Stengel, Kimberly M. Stanke, Amanda C. Quattrone, Joshua R. Herr

Department of Plant Pathology: Faculty Publications

Species concepts have long provided a source of debate among biologists. These lively debates have been important for reaching consensus on how to communicate across scientific disciplines and for advancing innovative strategies to study evolution, population biology, ecology, natural history, and disease epidemiology. Species concepts are also important for evaluating variability and diversity among communities, understanding biogeographical distributions, and identifying causal agents of disease across animal and plant hosts. While there have been many attempts to address the concept of species in the fungi, there are several concepts that have made taxonomic delimitation especially challenging. In this review we discuss …

Ecological And Morphological Differentiation Among Coi Haplotype Groups In The Plant Parasitic Nematode Species Mesocriconema Xenoplax, Julianne N. Matczyszyn, Timothy Harris, Kirsten S. Powers, Sydney E. Everhart, Thomas O. Powers

Department of Plant Pathology: Faculty Publications

DNA barcoding with the mitochondrial COI gene reveals distinct haplotype subgroups within the monophyletic and parthenogenetic nematode species, Mesocriconema xenoplax. Biological attributes of these haplotype groups (HG) have not been explored. An analysis of M. xenoplax from 40 North American sites representing both native plant communities and agroecosystems was conducted to identify possible subgroup associations with ecological, physiological, or geographic factors. A dataset of 132 M. xenoplax specimens was used to generate sequences of a 712 bp region of the cytochrome oxidase subunit I gene. Maximum-likelihood and Bayesian phylogenies recognized seven COI HG (≥99/0.99 posterior probability/bootstrap value). Species delimitation …

Ecological And Morphological Differentiation Among Coi Haplotype Groups In The Plant Parasitic Nematode Species Mesocriconema Xenoplax, Julianne N. Matczyszyn, Timothy Harris, Kirsten S. Powers, Sydney E. Everhart, Tom Powers

Department of Plant Pathology: Faculty Publications

DNA barcoding with the mitochondrial COI gene reveals distinct haplotype subgroups within the monophyletic and parthenogenetic nematode species, Mesocriconema xenoplax. Biological attributes of these haplotype groups (HG) have not been explored. An analysis of M. xenoplax from 40 North American sites representing both native plant communities and agroecosystems was conducted to identify possible subgroup associations with ecological, physiological, or geographic factors. A dataset of 132 M. xenoplax specimens was used to generate sequences of a 712 bp region of the cytochrome oxidase subunit I gene. Maximum-likelihood and Bayesian phylogenies recognized seven COI HG (≥99/0.99 posterior probability/bootstrap value). Species …

Global Distribution And Richness Of Armillaria And Related Species Inferred From Public Databases And Amplicon Sequencing Datasets, Rachel A. Koch, Joshua Herr

Department of Plant Pathology: Faculty Publications

Armillaria is a globally distributed fungal genus most notably composed of economically important plant pathogens that are found predominantly in forest and agronomic systems. The genus sensulato has more recently received attention for its role in woody plant decomposition and in mycorrhizal symbiosis with specific plants. Previous phylogenetic analyses suggest that around 50 species are recognized globally. Despite this previous work, no studies have analyzed the global species richness and distribution of the genus using data derived from fungal community sequencing datasets or barcoding initiatives. To assess the global diversity and species richness of Armillaria, we mined publicly available sequencing …