Special Sessions by Topic

Biology of Plant Pathogens

Co-Evolution of Fungi and Plants
Monday, August 2

Sponsoring Committees: Mycology, Genetics
Organizers: Dean Glawe, Washington State University, Puyallup, WA, and Karel Jacobs, The Morton Arboretum, Lisle, IL

This is an exploration of current thinking on the interactions of fungi and plants as expressed through common evolutionary histories. Topics range from current thinking on the origin and diversification of plants and theoretical foundations of fungi-plant co-evolution to focused talks on the evolution of mycorrhizal symbioses, endophytism, and pathogenesis among different plant-fungi interactions.

Fungal/plant interactions during the early terrestrialization of the land. T.N. TAYLOR. University of Kansas, Lawrence, KS

Evolutionary dynamics of the interactions between plants and arbuscular mycorrhizal fungi. J. BEVER. Indiana University, Bloomington, IN

Host specialization of endophytes and coevolution. C. SCHARDL. University of Kentucky, Lexington, KY

The human impact on plant disease; it's not all bad. G. MAY. University of Minnesota, St. Paul, MN

Phylogeographic studies on tree pathogens reveal differing patterns of speciation and host pathogen co-evolution. B.D. WINGFIELD. University of Pretoria, Pretoria, South Africa

Geological time, evolutionary rates, and the history of fungi. J.W. TAYLOR. University of California, Berkeley, CA

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Current Insights into the Genetics, Toxicology, and Plant Pathology of Fusarium Verticillioides
Sunday, August 1

Sponsoring Committee: Mycotoxicology
Organizer: Charles Woloshuk, Purdue University, West Lafayette, IN

One hundred years ago, John Lewis Sheldon first described the association between the toxicosis in farm animals and corn infected with Fusarium moniliforme, now designated F. verticillioides (Sacc.) Nirenberg (teleomorph: Gibberella moniliformis Wineland). This plant pathogen causes seedling blight, root rot, stem rot, and kernel/ear rot of corn and produces biologically active metabolites, including a group of mycotoxins called fumonisins. When consumed by animals, fumonisins cause diseases such as leukoencephalomalacia in equids and pulmonary edema in pigs. Fumonisin B1 causes liver and kidney cancer in rodents and has been classified as possibly carcinogenic to humans. The toxin causes neural tube defects in mice and has been suggested to be a risk factor for neural tube defects in humans. Due to the potential health risks, guidelines for fumonisin levels in food have been established by the U.S. Food and Drug Administration and by other government agencies worldwide. This symposium will begin with an overview of the pathology, taxonomy, and worldwide importance of F. verticillioides. A series of lectures will follow on topics that include: host resistance and disease management, genomics research, functional analysis of the genes involved in fumonisin biosynthesis, factors affecting fumonisin biosynthesis in colonized kernels, and risk assessment of fumonisins in food.

Perspectives on the history and taxonomy of Fusarium verticillioides (teleomorph, Gibberella moniliformis). A.E. Desjardins, USDAARS, Peoria, IL

The fumonisin risk assessment and emerging issues. R.T. Riley, USDA-ARS, Athens, GA

Elucidation of the biosynthetic pathway by deletion analysis. R. Butchko, USDA-ARS, Peoria, IL

Genomics approach for solving a mycotoxin problem in maize. R. Proctor, USDA-ARS, Peoria, IL

Effect of microenvironment on fumonisin biosynthesis. C.P. Woloshuk, Purdue University, West Lafayette, IN

Identification and potential use of genetic resistance to control fumonisin accumulation in corn grain. D.G. White, University of Illinois, Urbana, IL

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Functional Genomics Meets Bacterial Diseases
Monday, August 2

Sponsoring Committees: Bacteriology, Genetics
Organizers: Sheng Yang He, Michigan State University, East Lansing, MI, and Gwyn Beattie, Iowa State University,Ames, IA

With increasing numbers of bacterial pathogen genomes completely sequenced and functional genomic resources available for these pathogens, researchers now have excellent opportunities to address unresolved long-standing questions about the ecology, epidemiology, pathology, and control of bacterial diseases. This symposium seeks to integrate knowledge of genomics with knowledge of the biology of Pseudomonas syringae and Ralstonia solanacearum. The goal of the session is to explore how genomics has furthered and will continue to further our understanding of the ecology, epidemiology, pathology, and control of these organisms. This session is envisioned as the first of a series, with other plant pathogenic bacteria to be scheduled in subsequent years.

Pseudomonas syringae: A cosmopolitan pathogen with varied interactions with plants? S. Lindow, University of California, Berkeley, CA

Pseudomonas syringae pathogenicity explored from the perspective of type III secretion systems and comparative genomics. A. Collmer, Cornell University, Ithaca, NY

Pseudomonas syringae DC3000: Old pathogen, new name? C. Bender, Oklahoma State University, Stillwater, OK

The Ralstonia solanacearum species complex: Genetic diversity and physiology of the pathogen and ecology of bacterial wilt. A.C.

Hayward, University of Queensland, Brisbane, Australia Pathogenicity determinants and genomics of Ralstonia solanacearum. S. Genin, INRA, Castanet Tolosan, France

Extracellular space: The final frontier for Ralstonia solanacearum proteins required for colonization. T.P. Denny, University of Georgia, Athens, GA

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Genome-Based Studies of Fungal-Plant Pathosystems
Wednesday, August 4

Sponsoring Committees: Biochemistry, Physiology, and Molecular Biology
Organizers: Thomas Mitchell, North Carolina State University, Raleigh, NC, and Michael Thon, Texas A&M University, College Station, TX

Genome sequences are becoming available for an increasing number of fungal plant pathogens and their respective hosts. The current challenge is to employ gene annotation tools, gene expression studies, and other information to assign gene functions within the context of the organism's biology. While computational and experimental tools for genome-wide studies are being developed and implemented, our overall understanding of genome structure, content, and gene function is modest. This symposium will explore advances, discoveries, and related technologies from genome-based studies of select fungal-plant pathosystems.

Functional genome analysis of Magnaporthe grisea. R. Dean, North Carolina State University, Raleigh, NC

Genomics of the wheat and barley pathogen, Fusarium graminearum. J.-R. Xu, Purdue University, West Lafayette, IN

Genome sequencing and gene expression in Aspergillus flavus. G. Payne, North Carolina State University, Raleigh, NC

The use of microarrays for the identification of virulence genes in Ustilago maydis. R. Kahmann, Max-Planck-Institut fuer Terrestrische Mikrobiologie, Marburg, Germany

Proteomic identification and functional analyses of extracellular proteins from the rice blast fungus. S.-C. Wu, University of Georgia, Athens, GA

Comparison of arabidopsis responses to Alternaria brassicicola and Pseudomonas syringae by expression profiling. J. Glazebrook, University of Minnesota, St. Paul, MN

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Life Styles and Genomics of Fastidious and Gram-Positive Bacteria
Monday, August 2

Sponsoring Committee: Bacteriology
Organizers: Saskia Hogenhout, Ohio State University, Wooster, OH, and Carol Ishimaru, Colorado State University, Ft. Collins, CO

The genomes of an increasing number of Gram-positive plant-pathogenic bacteria and organisms closely related to Gram-positive bacteria, such as the fastidious spiroplasmas and phytoplasmas (class Mollicutes), are being sequenced. So far, most bacterial genomics symposia at APS annual meetings have focused on Gram-negative bacterial plant pathogens. The goal of this symposium is to provide an update on genomics of Gram-positive and fastidious bacterial plant pathogens and help integrate genomic information on these organisms. The symposium will include seminars on comparative and functional genomics, and proteomics of Clavibacter, Streptomyces, spiroplasmas and phytoplasmas.

A functional equivalent of a Type III secretion in Gram-positive bacteria. M. Caparon, Washington University School of Medicine, St. Louis, MO

Pathogenicity islands of Streptomyces spp. R. Loria, Cornell University, Ithaca, NY

The Spiroplasma kunkelii genome: Clues to a parasitic lifestyle in insects and plants. R. Davis, USDA-ARS, Beltsville, MD

Phytoplasmas: From structural to functional genomics. S. Hogenhout, Ohio State University, Wooster, OH

The genome of the phytopathogenic bacterium Clavibacter michiganensis subsp. michiganensis. R. Eichenlaub, Universitaet Bielefeld, Bielefeld, Germany

Genome sequencing of Clavibacter michiganensis subsp. sepedonicus. C. Ishimaru, Colorado State University, Fort Collins, CO

The interaction proteome of tomato and Clavibacter michiganensis. D. Francis, Ohio State University, Wooster, OH

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Diseases of Plants

Pepino Mosaic Virus in Tomato
Tuesday, August 3

Sponsoring Committees: Seed Pathology, Diagnostics
Organizers: Harrie Koenraadt, Naktuinbouw, Roelofarendsveen, Netherlands, and Phyllis Himmel, Seminis Vegetable Seeds, Woodland, CA

Pepino mosaic virus (PepMV), a potexvirus, was first described in pepino (Solanum muricatum) growing along the coastal regions of Peru in 1980. In 1999 it was identified as the causal agent of a severe tomato disease in commercial greenhouses in the Netherlands. Today, PepMV is a serious problem in greenhouse tomatoes throughout Europe, Canada, and the United States. The origin and rapid spread of PepMV, detection programs, management strategies, and the impact of this disease on tomato production in the U.S., Canada and Europe will be discussed.

Origin and spread of Pepino mosaic virus in tomato. P. Himmel, Seminis Vegetable Seeds, Woodland, CA

Emergence of PepMV in the Netherlands and the response of the seed industry to investigate the disease and address the risks posed by seed transmission. B. Woudt, Syngenta, Netherlands

Inspection services and regulatory history in Europe. H. Koenraadt, Naktuinbouw, Roelofarendsveen, Netherlands

Management and control of PepMV in commercial tomato productions in North America. A. Turnbull, Syngenta, Boise, ID

PepMV detection strategies. W. Bliss, Agdia, Inc., Elkhart, IN

Greenhouse manager perspective. Speaker to be announced

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Species Concept in Host Pathogen Interactions: What is its Effect on Breeding for Resistance
Sunday, August 1

Sponsoring Committee: Host Resistance
Organizer: Monte Miles, USDA-ARS, Urbana, IL

The concept of what is a species, along with changes in nomenclature as pathogen species are reclassified, has an impact on evaluation of host resistance. What is this impact and how have the changes influenced research in some programs?

Introduction: Species concept in a commercial breeding program? M.R. Miles, USDA-ARS, Urbana, IL

Host gene-pool specialization and species concepts in Uromyces appendiculatus and other pathogens of common bean. T. Pastor-Corrales, USDA-ARS, Beltsville, MD

From one species to many or many species to one? The case of begomoviruses. J. Brown, University of Arizona, Tucson, AZ

Puccinia recondita, leaf rust of cereal and grasses: Who’s who? L. Szabo, USDA-ARS, St. Paul, MN

Will changes in species names matter to a breeding program? M. Carson, USDA-ARS, St. Paul, MN

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Epidemiology/Ecology/Environmental Plant Pathology

Active Management of Soil Microorganisms for Plant Root Disease Control
Tuesday, August 3

Sponsoring Committeea: Soil Microbiology and Root Disease, Biological Control
Organizer: Brantlee Richter, BBC Laboratories, Inc., Tempe, AZ

Research over the past several decades has yielded new insights into soil microbial community structures and the interactions between plant pathogens and other microorganisms in the environment. As this body of knowledge grows, there have been increased attempts in the field to manage soil microorganisms in order to decrease disease pressure through use of single-species biocontrol products, multi-species biological inoculants, and cultural techniques designed to maintain or increase certain components of soil microbial communities. This session will explore the impact of cultural techniques and biological amendments on soil microbial communities and, in turn, the impact of the managed soil communities on plant root disease occurrence.

Disease suppressive soils: Mechanisms and indicators based on microbial responses and soil chemical/physical properties. R.P. Dick, Ohio State University, Columbus, OH

Crop rotation and amendment effects on soil microbial communities and soilborne diseases. R. Larkin, USDA-ARS, Orono, ME

Significance of host genotype in exploitation of resident disease suppressive soil microbial communities. M. Mazzola, USDA-ARS, Wenatchee, WA

Management of soil microorganisms for the control of Phytophthora root rot of avocado and citrus. J. Menge, University of California, Riverside, CA

Effect of cover crop decomposition on soil microbial and plant pathogen dynamics. N. Grunwald, USDA-ARS, Prosser, WA

Role and use of arbuscular mycorrhizae in root disease management. R.G. Linderman, USDA-ARS, Corvallis, OR

Perspectives from the field: A grower’s trials and tribulations. S. Pavich, Pavich Agricultural Consulting, Dateland, AZ

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Challenges at the Urban/Ag Interface
Tuesday, August 3

Sponsoring Committees: Extension, Integrated Pest Management, Regulatory Plant Pathology
Organizer: George Leavitt and Stephen Vasquez. UCCE Madera and Fresno Counties.

This symposium will highlight the problems associated with a large urban population encroaching upon production agriculture. California, with its large population centers (Los Angeles and San Francisco Bay area) and highly productive agriculture industry, experiences many of these challenges faced at the urban/ag interface. In southern California alone there are three international airports and two major harbors where foreign and domestic passengers enter the United States from hundreds of foreign countries, increasing the potential for unwanted pests and diseases. Border inspection stations are manned on all major highways coming into California to prevent the entry of unwanted pests that may be found on imported on plant material or alternative avenues. Mexican fruit fly, glassy winged sharpshooter (GWSS), Mediterranean fruit fly and Newcastle disease are only recent examples of infestations into California that have occurred in the past few years. In short, this symposium will address enormous job of protecting the environment, the people and the 30 billion-dollar agricultural industry of California.1:00 Welcome and Introduction - George Leavitt, UCCE Farm Advisor, Madera County

1:00 Welcome and Introduction - George Leavitt, UCCE Farm Advisor, Madera County

1:05 p.m. Social and Financial Impacts of Inadvertent Introduction of Exotic Pests on California Agriculture. Musa Abdelshife, USDA, APHIS, PPQ. Hawthorne, Ca.

1:40 pm Pest exclusion: Preventing, controlling and eradication of invasive pests. David Kellum, Senior Economic Entomologist, Department of Agriculture / Weights & Measures, San Diego County, CA

2:15 p.m. Problems Between Home Owners and Growers at the Urban/Ag interface: Perspective of an Agricultural Commissioner. Kathleen Thuner, Agricultural Commissioner - Department of Agriculture/Weights & Measures, San Diego County, CA

2:45 pm Break

3:00 p.m. Managing neighbor and community relations - The California winegrape experience . Joe Browde, California Sustainable Winegrowing Alliance.

3:30 p.m. Topic: Being a Good Neighbor: Challenges of Small Acreage Farming in Urban Areas Valerie Mellano, Environmental Issues Farm Advisor, University of California Cooperative Extension San Diego County. Panel Discussion with growers who farm at the Ag/Urban Interface

4:30 Wrap Up

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Co-Evolutionary Processes of Introduced Pathogens and Hosts in Natural Ecosystems Monday, August 2

Sponsoring Committees: Forest Pathology, Graduate Student
Organizers: Richardson, Mee-Sook Kim, and Ned Klopfenstein, USDA Forest Service, Moscow, ID

Introduced pathogens have produced many classic examples of ecosystem devastation. However, for many pathosystems, co-evolutionary processes should cause decreases in pathogen aggressiveness and increases in host resistance. Understanding naturalization processes of introduced pathogens is critical to fostering recovery of natural ecosystems. This symposium offers valuable insights into the growing fields of evolutionary epidemiology and population genetics.

Implications of molecular evidence on the evolution of Melampsora and other rust fungi. M. Pei, University of Bristol, Bristol, UK

A phylogeographical history of Mycosphaerella graminicola on wheat. B.A. McDonald, Swiss Federal Institute of Technology, Zurich, Switzerland

Epidemiology meets genetics: The evolution of virulence in a natural plant-pathogen association. P. Thrall, CSIRO Plant Industry, Canberra, ACT, Australia

Inferring patterns of migration and gene flow in introduced populations of plant pathogens using the chickpea pathogen Ascochyta rabiei as a model. T.L. Peever, Washington State University, Pullman, WA

Exotic and native rust pathosystems: A population genomics approach. R. Hamelin, Natural Resources Canada, Sainte-Foy, QC, Canada

Implications from deep phylogeographical histories on pathosystem endemism. G. McDonald, USDA Forest Service, Moscow, ID

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Food Safety as Influenced by Phyllosphere Microflora
Tuesday, August 3

Sponsoring Committee: Phyllosphere Microbiology
Organizer: Walter Mahaffee, USDA-ARS, Corvallis, OR

This symposium will focus on the role of preharvest microflora on the establishment of human pathogens and subsequent food safety risks. Individual speakers will address factors that influence establishment and persistence of human pathogens on fruit and edible foliage from preharest through processing and storage.

Putting science to work: Separating the possible from the plausible. T. Suslow, University of California, Davis, CA

Going from compost to compost tea: Weighing plant health benefits against human pathogen uncertainties. S. Scheuerell, Oregon State University, Corvallis, OR

Use of non-composted bovine manure as fertilizer: An evaluation of vegetable contamination risk. S. Ingham, University of Wisconsin, Madison, WI

Biofilms and other strategies exploited by Salmonella and friends on plants. J. Barak, USDA-ARS, Albany, CA

Fitness of Salmonella enterica in the phyllosphere. M. Brandl, USDA-ARS, Albany, CA

Influence of indigenous bacteria on survival of human pathogens on plants. C. Poza-Carrión, University of California, Davis, CA

Infective dose of enteric pathogens: Influence of postharvest processing and storage practices. A. Bhagwat, USDA-ARS, Beltsville, MD

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The Plant Pathologist’s Toolkit for Responding to Crop Biosecurity Threats
Wednesday, August 4

Sponsoring Committees: Plant Disease Losses, Epidemiology
Organizers: Forrest Nutter, Iowa State University, Ames, IA, and Denis Shah, New York State Agricultural Experiment Station, Geneva, NY

This symposium will address our ability to respond to post-introduction plant biosecurity threat agents. The intentional bioterrorism attacks directed at U.S. agriculture is now recognized as a serious threat to U.S. agriculture and its economy. Efforts to prevent the introduction of new and emerging agricultural pathogens and pests have significantly increased since September 11. Coordination within and among key federal, state, land grant institutions, and private industry to detect, respond to, and recover from potential for confirmed agricultural threats have also significantly improved. Individual speakers will address the tools needed by plant pathologists to answer post-introduction questions such as: 1) what is it, 2) where is it now? 3) where will it likely spread? 4) will it become established? and 5) what plant disease mitigation/management practices are available?

The role of CSREES in responding to new and emerging agricultural pathogens. K. Cardwell, USDA CSREES PAS, Washington, DC

The role of NPDN in responding to new and emerging agricultural pathogens. J. Stack, Kansas State University, Manhattan, KS

What is on the horizon concerning new tools for detection of plant pathogens? R. Martin, USDA-ARS, Corvallis, OR

Post-introduction mapping of new and emerging agricultural pathogens in real-time using GPS and GIS technologies. F. Nutter, Iowa State University. Ames, IA

Use of aerobiological information and meteorological trajectory analysis to predict and monitor spread of plant disease epidemics. C. Main, North Carolina State University, Raleigh, NC

Weather-based simulations of invasive plant pathogens. J. Russo, ZedX, Inc., Bellefonte, PA

Mitigating the post-introduction impacts of new and emerging agricultural pathogens. T. Gottwald, USDA-ARS, Ft. Pierce, FL

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Soil Health and Nematodes
Monday, August 2

Sponsoring Committee: Nematology
Organizers: Senyu Chen, University of Minnesota, Waseca, MN; Koon-Hui Wang, University of Florida, Gainesville, FL; and Terrence Kirkpatrick, University of Arkansas, Hope, AR

Maintaining soil heath is critical for sustainable agriculture. Soil ecosystems support diverse groups of organisms including fungi, bacteria,algae, protozoa, arthropods, annelids, and nematodes. A healthy agricultural soil ecosystem should provide optimum nutrients for plant growth while it maintains low disease, pest, and weed pressures. The soil ecological health and conditions can be analyzed by studying soil microflora and fauna. Nematodes are a useful group of organisms as soil bioindicators. Nematodes play a significant role in soil nutrient cycling, especially in organic matter decomposition and nitrogen mineralization. Nematodes represent various trophic levels in the food web including primary (plant and algae feeders), secondary (bacterial and fungal feeders), and tertiary (predators) consumers. A healthy soil may contain more free-living nematodes and fewer plant-parasitic nematodes. In this session, the speakers will discuss various aspects of nematode ecology associated with soil heath and ecological-based nematode management.

Nematode diversity in soil ecosystems. G.W. Yeates, Landcare Research, Palmerston North, New Zealand

Role of nematodes in soil nutrient cycling. G.W. Bird, Michigan State University, East Lansing, MI

Decoding the nature of a nematode suppressive soil. J.O. Becker, University of California, Riverside, CA

Soil microbial and nematode communities in organic and conventional farming systems. J.B. Ristaino, North Carolina State University, Raleigh, NC

Effects of soil ecosystem management on nematode pests, nutrient cycling, and plant health. K.H. Wang, University of Florida, Gainesville, FL

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Molecular/Cellular Plant-Microbe Interactions

Closteroviruses—Citrus Tristeza Virus Complex and Tristeza Diseases
Sunday, August 1

Sponsoring Committee: Virology
Organizers: Alexander Karasev, Thomas Jefferson University, Doylestown, PA, and Mark Hilf, USDA-ARS, Fort Pierce, FL

The family Closteroviridae comprises more than 30 plant viruses with flexuous, filamentous virions and includes representatives with either mono- or bipartite positive strand ssRNA genomes. Closteroviruses are transmitted semi-persistently by insects from three families of Homoptera and have apparently co-evolved with their insect vectors, resulting in three major lineages, i.e., aphid-, mealybug-, and whitefly-transmitted viruses. Closteroviruses pose serious threats to agriculture and need serious attention. This symposium seeks to demonstrate a comprehensive research effort necessary to control and manage a representative aphid-transmitted closterovirus, Citrus tristeza virus (CTV), causing a complex of tristeza syndromes in citrus. Economically, CTV is one of the most damaging plant pathogens in the world. To manage the tristeza problem, a sophisticated research effort is needed. This research effort ranges from epidemiology and plant pathology to molecular virology and cell biology.

Citrus tristeza diseases—A worldwide perspective. S.M. Garnsey, Univeristy of Florida, Lake Alfred, FL

Citrus tristeza virus as a model and a tool—Replication, assembly, interactions with the host, and transmission. W.O. Dawson, University of Florida, Lake Alfred, FL

Variation in composition and biology of Citrus tristeza virus defective RNAs. M. Bar-Joseph, The Volcani Center, Bet Dagan, Israel

An overview of the epidemiology of Citrus tristeza virus. T.R. Gottwald, USDA-ARS, Ft. Pierce, FL

Transmissibility and genotype analysis of central California isolates of Citrus tristeza closterovirus. R.K. Yokomi, USDA-ARS, Parlier, CA

Citrus tristeza virus: Evolution in a host-limited pathosystem. M. Hilf, USDA-ARS, Fort Pierce, FL

Citrus tristeza virus genome encodes three distinct suppressors of RNA silencing. S.-W. Ding, University of California, Riverside, CA

Positional cloning of the Citrus tristeza virus resistance gene. T.E. Mirkov, Texas A&M University, Weslaco, TX

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Fungal Melanins: Biology and Pathogenesis
Tuesday, August 3

Sponsoring Committee: Mycology
Organizers: Weidong Chen, USDA-ARS, Pullman, WA, and Carol Stiles, University of Florida, Gainesville, FL

Fungal melanins are polymeric compounds generally considered nonessential for growth. These metabolites, however, have been shown to be essential for fungal infection and pathogenesis in plants and animals. These pigments fall into different chemical groups, depending on their phenolic precursors, and they differ in color (green, brown or black). Fungal melanins have been studied for over three decades. This will be the first APS special session to focus on them. This symposium will bring together experts in fungal melanin research to present historical and contemporary perspectives and the progress made in understanding the biosynthesis and functions of these polymers. The role of the melanins as virulence factors in certain diseases will be emphasized.

Biochemistry and genetics of fungal melanin biosynthesis. M. Wheeler, USDA-ARS, College Station, TX

The mechanical value of fungal melanin. N. Money, Miami University, Oxford, OH

Fungal melanins and human diseases. A. Casadevall, Albert Einstein College of Medicine, Bronx, NY

Role of fungal melanin in Ascochyta blight of chickpea. W. Chen, USDA-ARS, Pullman, WA

Fungal melanin and take-all disease. H. Wilkinson, University of Illinois, Urbana, IL

Fungal melanin and rice blast disease. B. Valent, Kansas State University, Manhattan, KS

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Host-Microbe Interactions in Woody Plants
Monday, August 2

Sponsoring Committees: Forest Pathology; Biochemistry, Physiology, and Molecular Biology
Organizers: Pierluigi Bonello, Ohio State University, Columbus, OH and Paul Zambino, US Forest Service, Moscow, ID.

In the past 20 years significant advances have been made in our understanding of host-microbe interactions, particularly through the manipulation of selected herbaceous model plant systems such as Arabidopsis and tobacco. While there are obstacles in manipulating trees, there are also tremendous opportunities to expand our knowledge of host-microbe interactions to a group of organisms that are a dominant feature in many terrestrial ecosystems and are of critical economic importance. Certain unique features of trees cannot be easily modeled using herbaceous systems, including the predominance of secondary tissues in trees; the existence of woody plant-specific defense mechanisms, such as the resin system in conifers and compartmentalization processes; and the large temporal and spatial scales at which defenses must presumably act given the longevity and size of trees. Furthermore, fundamental information is being generated in the field of plant-mycorrhizal fungus interactions, an area that is arguably better characterized in woody than in herbaceous plants. This symposium will focus on the latest discoveries in the areas of genomics, genetics, biochemistry, and cell and tissue biology of host-microbe interactions in woody plants, including pathogenic and mycorrhizal associations, and will provide a forum for the identification of future research directions.

Introduction.

Genomic approaches to understanding quantitative inheritance of disease resistance in forest trees. D.B. NEALE (1,2), E.S. Ersoz (1), G.R. Brown (1), A. Morse (3), and J.M. Davis (3).(1) University of California, Davis, CA; (2) USDA Forest Service, Davis, CA; (3) University of Florida, Gainesville, FL

Genetic architecture of loblolly pine interactions with contrasting pathogens. J.M. DAVIS (1), A.M. Morse (1), D.A. Huber (1), C.D. Nelson (2), and S.F. Covert (3). (1) University of Florida, Gainesville, FL; (2) USDA Forest Service, Saucier, MS; (3) University of Georgia, Athens, GA

Anatomy, histochemistry, and cytochemistry of host-pathogen interactions in conifers. V.R. FRANCESCHI. Washington State University, Pullman, WA

Fine anatomy and chemical characterization of compartmentalization processes in response to Dutch elm disease and Scleroderris canker. D. RIOUX. Canadian Forest Service, Sainte-Foy, QC, Canada

Biochemistry of localized and systemic induced defense responses in pine. P. BONELLO. Ohio State University, Columbus, OH

Exploring the transcriptome of the ectomycorrhizal symbiosis. A. KOHLER, M. Peter, A. Jambois, P.E. Courty, S. Duplessis, F. Lapeyrie, and F. Martin. INRA, Champenoux, France

Relevance of herbaceous plant models to understanding and manipulating disease resistance in woody plants. A.F. BENT. University of Wisconsin, Madison, WI

Discussion

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Interactions Between Plant Pathogens and Their Vectors
Wednesday, August 4

Sponsoring Committee: Virology
Organizer: Judith Brown, University of Arizona, Tucson, AZ

Plant pathogens are transmitted by a variety of organisms upon which they rely for dispersal between susceptible hosts, although the majority have arthropod vectors. Important advances have been made toward elucidating the molecular and cellular mechanisms that govern interactions between plant pathogens and their biotic vectors, and the underlying basis for co-evolved pathogen-vector specificity. In this symposium vector-associated anatomical, cellular, molecular, and genetic factors, together with pathogen-associated determinants that confer pathogenplant host specificity, will be explored for several model pathogen-vectorhost plant systems. Plant pathogens represented include a mollicute, a replicative, circulative plant virus, several non-replicative, circulative plant viruses of either monocot or dicot hosts, and a plant-infecting trypanosomatid of subtropical, woody monocots. These plant pathogens are transmitted in a highly specific manner by their respective arthropod vector, which include a true bug, thrips, and four different homopterans (Hemiptera), collectively representing feeding specializations in plant meristems, plant leaves and stems, or cells and tissues of the plant vasculature.

Anatomy of the whitefly vector Bemsia tabaci and begomoviral capsid determinants involved transmission. J. Cicero, University of Arizona, Tucson, AZ

Molecular characterization of plant-parasitizing trypanosomes killing coconut and oil palm in Latin America. M. Dollet, CIRAD, Montpellier, France

Mapping of domains of the Beet curly top virus capsid protein involved in viral movement, virion formation, and leafhopper transmission. R.L. Gilbertson, University of California, Davis, CA

Cellular and molecular regulation of luteovirus transmission by aphid vector species and clonal populations. F. Gildow, Pennsylvania State University, University Park, PA

Rhabdovirus host range: A bug’s view. P. Redinburgh, USDA-ARS, Wooster, OH

Tospovirus-vector relations that drives the spread of disease. A. Kritzman, University of Kentucky, Lexington, KY

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Rice: A Model Crop that Has Pushed the Frontiers of Plant Pathology and Our Understanding of Host/Pathogen Interactions
Wednesday, August 4

Sponsoring Committee: Tropical Plant Pathology
Organizer: Lee Calvert, CIAT, Cali, Colombia

The United Nations has proclaimed 2004 as the International Year of Rice. This is the first time that a year is dedicated to a crop and it reflects the importance of rice as a staple food throughout the world. Rice has one of the smallest genomes, and it is the only major crop that the complete sequence is available. The sequences for viral, bacterial and one major fungal disease (rice blast) are also sequenced. It is timely that we review the progress that has been made using rice and its pathogens as models for studying host/pathogen interactions. In this seminar, there will be presentations on the host/plant interactions of Magnaporthe grisea and Xanthomonas oryzae, as well as other pathogens. The role of rice genomics in studying host/pathogen interactions will be discussed. Our knowledge about host/pathogens interactions is progressing rapidly because of the studies on rice and it is contributing to the sustainable production that is needed for the billions of people who depend on rice for their livelihoods.

Rice: A model crop that feeds the world. F. Correa, CIAT, Cali, Colombia

Signaling in the rice Xa21-mediated defense response. P. Ronald, University of California, Davis, CA

A genomics approach to pathogenicity: Saturation insertional mutagenesis in Magnaporthe grisea. M. Orbach, University of Arizona, Tucson, AZ

Elucidation of the molecular mechanism of recognition, evolution and defense signaling of the broad-spectrum resistance to rice blast. G.-L. Wang, Ohio State University, Columbus, OH

Candidate gene approach to durable disease resistance in rice. J. Leach, Kansas State University, Manhattan, KS

Understanding conventional and transgenic resistance to rice viruses. L. Calvert, CIAT, Cali, Colombia

Discussion: How rice as a model crop advances our knowledge in plant pathology and improves the livelihoods of rice farmers

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Suppression of Host Defense Responses by Pathogens
Monday, August 2

Sponsoring Committees: Genetics; Biochemistry, Physiology, and Molecular Biology
Organizers: Sophien Kamoun, Ohio State University, Wooster, OH, and John M. McDowell, Virginia Tech, Blacksburg, VA

Suppression of host defense responses by plant pathogens forms a key mechanism of pathogenicity. The objective of this symposium is to provide an update on recent advances in this area and to illustrate the diversity of molecular strategies used by bacterial, fungal, and oomycete pathogens to suppress host defenses. Some of the themes that will be presented include the role of effector molecules in disabling cellular defenses and the hypersensitive responses, and the production of inhibitory molecules that target plant enzymes.

Suppression of plant defenses by bacterial pathogens. B. Staskawicz, University of California, Berkeley, CA

Suppression of plant defenses by bacterial pathogens. J. Alfano, University of Nebraska, Lincoln, NE

Suppression of plant defenses by fungal pathogens. B. Valent, Kansas State University, Manhattan, KS

Phytophthora glucanase inhibitors. J. Rose, Cornell University, Ithaca, NY

Phytophthora protease inhibitors. M. Tian, Ohio State University, Wooster, OH

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Plant Disease Management

Fungicide Development: From Discovery to Market Launch
Monday, August 2

Sponsoring Committees: Chemical Control, Industry
Organizers: Rami Soufi, The Scotts Company, Marysville, OH, and David Wedge, USDA, University, MS

The objective of this symposium is to highlight the processes, decision points, and business groups involved in developing a fungicide. Presentations will describe development activities, starting with the discovery of an active ingredient (AI) to the commercialization of different fungicidal products based on that AI.

Global fungicide markets and the forces driving fungicide discovery. D. Ouimette, Dow AgroSciences LLC, Indianapolis, IN

Fungicide screening and discovery: Finding one good compound hidden with one million losers. R. Kaiser, Bayer CropScience, Research Triangle Park, NC

Market and financial models used to make development decisions. M.B. Kopcinski, DuPont Crop Protection, Wilmington, DE

The myriad of options in the development decision: Matrix management. J. Frank, Syngenta Crop Protection, Greensboro, NC

Fungicide resistance profiling: A corporate vs. academic view. A. Tally, Syngenta Crop Protection, Greensboro, NC

The role of IR-4 in fungicide development. D. Thompson, IR-4, North Brunswick, NJ

Developing active ingredients as seed treatments. J.L. Riggs, Gustafson LLC, McKinney, TX

Developing fungicides for the specialities markets. K. Kalmowitz, BASF, Research Triangle Park, NC

New Products and Services
Tuesday, August 3

Sponsoring Committee: Industry
Organizer: Jim Frank, Syngenta Crop Protection, Greensboro, NC

This session provides a forum highlighting new products or services that are in the pipeline or are now offered to growers and researchers to aid them in managing or understanding plant diseases.

Radio modem for HOBO weather stations. E. Sandherr, Onset Computer Corporation, Bourne, MA

Quinoxyfen fungicide: 2004 U.S. launch. J. Mueller, Dow Agrosciences, Brentwood, CA

Headline update and utility on corn and soybeans. G. Fellows, BASF,

Research Triangle Park, NCConviron research greenhouse. D. Adair, Controlled Environments, Inc., Pembina, ND

Scholar: A new postharvest fungicide for citrus and pome fruit. A. Cochran, Syngenta Crop Protection, Visalia, CA

Scala brand fungicide from Bayer Cropscience. L. Fought, Bayer Cropscience, Research Triangle Park, NC

Pristine: Registration update and product performance in the southeastern U.S. S. Newell, BASF, Statesboro, GA

Pentra-Bark: Bark penetrating surfactant technology. B. Stringfellow, Agrichem-Fluence LLC, Medina, OH

Uniform: A new cotton fungicide for control of soilborne diseases. S. Rideout, Syngenta Crop Protection, Leland, MS

Recent enhancements and options of ARM Trial Research Management software. S. Gylling, Gylling Data Management, Inc., Brookings, SD

Amistar and Quadris opti: Two new fungicide products from Syngenta Crop Protection. P. Kuhn, Syngenta Crop Protection, Vero Beach, FL

Plant genetics and molecular service lab. D. Lawn, Ag-Biotech, Inc., Gilroy, CA

Fast, automatic and nondestructive quality- and phenotype-assessment of complete higher plants and agricultural products with the LemnaTec scanalyzer. J. Vandenhirtz, LemnaTec, Wuerselen, Germany

Pristine fungicide update for tree fruit, nuts and vines. J. Helm, BASF, Sanger, CA

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The Nature and Application of Biocontrol Microbes II: Trichoderma spp.
Tuesday, August 3

Sponsoring Committees: Biological Control, Soil Microbiology and Root Diseases
Organizer: Barry Jacobsen, Montana State University, Bozeman, MT

While diverse microbes may contribute to the biological control of plant pathogens, most research and development efforts have focused on isolates of three genera, Bacillus, Trichoderma, and Pseudomonas. The 2003 symposium on the nature and application of biocontrol microbes covered the genus Bacillus. This symposium will cover the taxonomy, genomics, mechanisms of action, and practical use of Trichoderma spp. in biocontrol of plant disease, plant growth and yield enhancement and related topics. This symposium should advance our understanding of the nature of biological control by members of the genus Trichoderma and improve our ability to successfully integrate Trichoderma mediated biological control into agricultural management and similar systems. A third symposium covering the genus Pseudomonas is planned for 2005.

Overview of new insights into mechanisms and uses of Trichoderma-based products. G. Harman, Cornell University, Ithaca, NY

Changes in taxonomy, occurrence of the sexual stage and ecology of Trichoderma spp. G. Samuels, USDA-ARS, Beltsville, MD

Systemic resistance induced by Trichoderma hamatum 382: Interactions between the host, the biocontrol agent and soil organic matter quality. H. Hoitink, Ohio State University, Wooster, OH

Understanding the mechanisms employed by Trichoderma virens to effect biological control. C. Howell, USDA-ARS, College Station,TX

The molecular biology of the interaction between Trichoderma, phytopathogenic fungi, and plants. M. Lorito, University of Naples, Portici, Italy

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Organic Foods—From Production to Market
Tuesday, August 3

Sponsoring Committee: Scientific Program Board
Organizer: Monica Elliott, University of Florida, Fort Lauderdale, FL

Organic farming is one of the fastest-growing segments of U.S. agriculture, with organic food sales reaching $9.3 billion in 2002. Standards for organic food established by the USDA were fully implemented in October 2002 and include the creation of National Organic Program Standards. The latter requires producers to use a planned systems approach to crop protection. This session will examine organic agriculture from a plant pathology perspective. Questions to be addressed include: Why is farming systems research important for organic agriculture? Are plant diseases a problem? If they are, what are the major pathogens and what are the controls? What is the function of the National Organic Standards Board? What are the funding sources for organic agricultural research?

Organic farming and plant disease research by the University of California 1987–2004. J.C. Broome, SAREP, University of California, Davis, CA

Best management practices on organic farms provide opportunities and challenges for applied and research plant pathology. D. O’Brien, Doug O’Brien Agricultural Consulting, Santa Cruz, CA

Farming systems research and extension in organic agriculture: A plant pathology perspective. F. Louws, North Carolina State University, Raleigh, NC

Compost teas: A tool for rhizosphere + phyllosphere agriculture. S. Diver, ATTRA, NCAT, Fayetteville, AR

Role of the National Organic Standards Board. R. Koenig, Rosie’s Organic Farm, NOSB, University of Florida, Gainesville, FL

Funding opportunities for research, extension and education from CSREES. T. Bewick, USDA-CSREES, Washington, DC

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Risk and Risk Management Associated with the International Movement of Plants for Planting
Tuesday, August 3

Sponsoring Committees: Regulatory Plant Pathology, Collections and Germplasm
Organizers: Arnold Tschanz, USDA APHIS, Riverdale, MD, and Kathy Kosta, California Department of Food and Agriculture, Sacramento, CA

A significant increase in the worldwide movement of plants and plant parts for planting and propagation is underway. This increase includes countries that have not been traditional trading partners in these plant materials. Movement of such materials can serve as a pathway for the introduction of quarantine-significant plant pathogens, pests, and invasive species into and within the United States. National and state efforts to quantify the risk and to coordinate policy and strategies for such plant materials have been limited. Some countries, including the United States, have begun or are considering reviewing and modifying their regulatory frameworks for trade in these plants for planting. The purpose of this discussion session is to define the risks associated with the movement of this plant material and to identify potential measures for mitigating pest risk while accommodating the movement of plants for planting in international trade.

International perspective. R.L. Griffin, USDA APHIS, Raleigh, NC

National perspective. W.E. Thomas, USDA APHIS, Riverdale, MD

State perspective. Speaker to be announced

Impact on the environment. F.T. Campbell, The Nature Conservancy, Arlington, VA

Impact on forestry. B.M. Tkacz, USDA Forest Service, Arlington, VA

Seed industry perspective. G.P. Munkvold, Pioneer Hi-Bred International Inc., Johnston, IA

Horticulture industry perspective. C. Regelbrugge, American Nursery & Landscape Association, Washington, DC

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Sampling for Pathogen Detection to Meet Quarantine and Certification Requirements
Tuesday, August 3

Sponsoring Committees: Plant Pathogen and Disease Detection, Diseases of Ornamental Plants
Organizers: Jean Williams-Woodward, University of Georgia, Athens, GA, and Peter Ellis, Phyto Diagnostics, North Saanich, BC, Canada

The potential for introducing a new or severely damaging disease on fruit, vegetable, and ornamental seed or plant propagation material is a very real concern within today's global marketplace. Recent outbreaks and introductions of Ralstonia solanacearum race 3 biovar 2 in geranium cuttings, Phytophthora ramorum (cause of “sudden oak death”) in ornamental nurseries in California and the Pacific Northwest, and Plum pox virus in stone fruits in Pennsylvania and Canada are just a few examples. This session will discuss design considerations for sampling and tracking the movement of plant pathogens with particular reference to quarantine and certification requirements. In addition, the concerns within existing programs covering several commodities, including tree fruit, small fruit, potatoes, and ornamental plants, will be addressed.

Strategies of sampling for detection. G. Hughes, University of Edinburgh, Edinburgh, UK

Looking for viruses in all the right places: New vectors and viruses in small fruit crops. R.R. Martin, USDA-ARS, Corvallis, OR

Innovations in detection technology to limit the dissemination of phytopathogens in seed. R.R. Walcott, University of Georgia, Athens, GA

Clean stock programs and virus detection in vegetatively propagated ornamental plants. J.A. Dodds, University of California, Riverside, CA

Sampling and detection of Phytophthora ramorum in ornamental nursery stock. C. Blomquist, California Department of Food and Agriculture, Sacramento, CA

Ralstonia in geraniums: A case study. M.J. Klopmeyer, Ball FloraPlant, West Chicago, IL Implementation of a sampling plan for eradication of plum pox virus. L. Levy, USDA, Beltsville, MD

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Professionalism/Service/Outreach

Adapting Teaching Styles and Techniques for a Changing Student Population
Monday, August 2

Sponsoring Committee: Teaching
Organizers: Edward Braun, Iowa State University, Ames, IA, and Melissa Riley, Clemson University, Clemson, SC

The student population is changing (demographics, interests and aspirations, learning styles, etc.). How can we change our courses and pedagogy to be more successful with university students of the present and future?

What research tells us about science learners. R. Wright Dunbar, Stanford University, Stanford, CA

Meeting the challenges of a changing student population. C. D'Arcy, University of Illinois, Urbana, IL

Using case studies to engage students in learning. M. Riley, Clemson University, Clemson, SC

Using technology and the internet to engage students in learning. D. Eastburn, University of Illinois, Urbana, IL

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APS Public Policy Board: Activities, Strategies and Perspectives
Tuesday, August 3

Organizer: John Sherwood, University of Georgia, Athens, GA:

The APS Public Policy Board is actively involved in issues related to plant pathology with current emphasis on agrosecurity, genomics, permitting and sustainable agriculture. We hope you will attend this session to learn more about the activities of the PPB and to discuss priorities and strategies for success in addressing issues in public policy that impact plant pathology.

Introduction: Sustainable agriculture initiative. J. Sherwood, University of Georgia, Athens, GA

Washington activities of the APS Public Policy Board. K. Eversole, Eversole Associates, Bethesda, MD

Progress on plant-associated microbial genomics and the APS microbial genomic sequencing list update. S. Gold, University of Georgia, Athens, GA

Proposal for establishment of a center for plant biosecurity. J. Fletcher, Oklahoma State University, Stillwater, OK

Status of review of issues surrounding movement of plant pathogens. S. Tolin, VPI & State University, Blacksburg, VA

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Art in APS
Sunday, August 1

Sponsoring Committee: Graduate Student
Organizer: Paul Esker, Iowa State University, Ames, IA

Art in phytopathology is a graduate student-run art exhibit that occurs during the Welcome Reception. The goal of the exhibit is to highlight the beauty that is phytopathology. Presentations are of a wide variety, ranging from field and microscopy photos to LCD simulations and demonstrations. This is a continuing event with a goal of presenting awards for the best exhibits at this year’s meeting.

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Plant Pathology in Historical Perspective
Monday, August 2

Sponsoring Committees: Scientific Programs Board, Bacteriology
Organizers: Christina Matta, University of Wisconsin, Madison, WI, and Paul Peterson, Clemson University, Florence, SC

The history of plant pathology and allied disciplines is almost completely uncharted, yet crucial, for understanding the shape of the field today and its relationship to other biological disciplines. This session examines key episodes in plant pathology, agricultural bacteriology and soil science in their formative decades around the turn of the 20th century, focusing primarily on the creation of plant pathology as a scientific specialty in the United States (with some attention to international contexts as well). The presenters, all historians of science, hope to establish a precedent for professional cross-communication between scientists and scholars interested in the history of science.

Bacteriology and plant pathology in late 19th century America: A short-lived (and forgotten) marriage. E. Kupferberg, Harvard Medical School, Cambridge, MA

William Farlow Laboratory and the beginning of the U.S. institutional plant pathology cryptogamy. G. Denis, Université de Lille, Lille, France

The living soil: Soil bacteria, ecology, and social cooperation. M. Finlay, Armstrong Atlantic State University, Savannah, GA

The great dying on the vine: Scientific responses to the phylloxera grapevine disaster, France 1867–1900. G. Gale, University of Missouri, Kansas City, MO

Reconsidering controversy: The Fischer-Smith debate and the development of biological disciplines. C. Matta, University of Wisconsin, Madison, WI

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Reality CV: Recent Successful Job Applicants and Field Leaders Tell it Like it is About the Present and Future of Plant Pathology Careers
Sunday, August 1

Sponsoring Committees: Placement, Industry, Graduate Student
Organizer: Alyssa Collins, University of Delaware, Newark, DE:

Speakers will include young professionals paired with seasoned authorities from the arenas of government, academia and industry. Recent candidates will relate their job-hunting success stories, how they achieved their goals, and what they wish they had known at the start, while field leaders describe the current climate and direction of careers in their respective areas. Special emphasis will be given to debunking the myths concerning careers in industry and addressing the needs of international students. The proceedings of “Reality CV” will be posted on APSnet in the ‘Careers & Placement’ area along with other materials as resources geared towards those seeking a career in plant pathology.

The reality of academia, from a young professional. L. Tredway, North Carolina State University, Raleigh, NC

The reality of academia, from a field leader. R. Bostock, University of California, Davis, CA

The reality of government, from a young professional. J. Dominiak, Maryland Department of Agriculture, Annapolis, MD

The reality of government, from a field leader. D. Luster, USDAARS, Ft. Detrick, MD

Job-hunting after graduation: Beating the odds as an international student. D. Fernando, University of Manitoba, Winnipeg, MB, Canada

Permit Regulations and Process Affecting Research and Diagnostics on Plant Pathogens Endemic in the U.S.
Wednesday, August 4

Organizers: James R. Steadman, University of Nebraska, Lincoln, NE, and Sue Tolin, Virginia Polytechnic Institute and State University, Blacksburg, VA

As a response to 9/11 and the perceived need for increased national security, Congress passed the Plant Protection Act. As a consequence of the implementation of the act by APHIS-Plant Protection and Quarantine, it has been increasingly difficult for plant pathologists to obtain a permit to move live pests and pathogens, to conduct research on imported pathogens, and to import or move pathogen cultures for research and diagnostic purposes. This discussion session provides an opportunity for presentation of effects of APHIS PPQ permitting regulations on the science and practice of plant pathology. Perspectives of scientists from USDA ARS, industry, and public institutions on the regulation will be presented, as well as the current viewpoint of APHIS-PPQ. The concept of an ideal permitting system will also be presented. This session will be an opportunity for a dialogue between APHIS-PPQ and the plant pathology stakeholder community of APS members.

Introduction and opening comments. J.R. STEADMAN. University of Nebraska, Lincoln, NE
The APHIS-PPQ permitting system for widely prevalent plant pathogens. M.J. FIRKO. USDA APHIS, Riverdale, MD
Impacts of permitting on disease diagnosis and pathogen surveillance. R. LORIA. Cornell University, Ithaca, NY
Effects of permitting on plant pathology research with the ARS. R. BENNETT. USDA-ARS, Beltsville, MD
Industry experiences with permitting for movement of pathogens and plants. P. HIMMEL.. Seminis Vegetable Seeds, Woodland, CA
Re-inventing the permitting system from a scientific basis. A. VIDAVER. University of Nebraska, Lincoln, NE

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