2017 Dickeya and Pectobacterium Summit: Speakers

Amy Charkowski is a plant pathologist who studies bacterial and viral diseases of potato to improve seed potato production systems. Her research group has described bacterial genes required for biofilm formation and virulence, has mapped plant virus resistance genes in potato, and has analyzed long-term datasets to describe the impact of changes in seed potato production systems. She has also had extensive experience in translating research results in pest and pathogen detection and management into farm-scale use.

Charkowski joined the Department of Bioagricultural Sciences and Pest Management at Colorado State University in 2016 as a professor and department head. From 2001-2015, Charkowski served as a professor at the University of Wisconsin-Madison. During this time, she was also the administrative director of the Wisconsin Seed Potato Certification Program and Lelah Starks Elite Foundation Seed Potato Farm, a program that supplies over 5% of the seed stock and certifies 7.5% of seed potatoes for the US potato industry.

Prior to working at UW-Madison, Charkowski was a research scientist in food safety with the USDA Agricultural Research Service, where she studied adherence of bacterial human pathogens to fresh fruits and vegetables. Her research efforts have been recognized with the Wisconsin Potato and Vegetable Grower of the Year Award, the American Phytopathological Society Syngenta Award, the Friday Chair for Vegetable Production Research at UW-Madison, and she was recently named an American Phytopathological Society Fellow.


Jianjun Hao is a plant pathologist at the University of Maine. Jay earned his Ph.D. degree in plant pathology at the University of California, Davis in 2000. His research interests include epidemiology of fungal and bacterial diseases of potato, soil microbial communities, and bio-based strategies in plant disease control. His current research projects include pink rot, late blight, common scab of potato, bacterial soft rot and blackleg of potato. By systemically studying disease suppressive soil, he has published series of research paper in elucidating the mechanisms of beneficial microorganisms that improve soil and plant health. He also holds a patented bacterial strain for biological control of soilborne diseases. He actively participates in various types of academic activities, student training, teaching, and international collaborations.


Dr. Jeffrey Hecker is the Executive Vice President for Academic Affairs and Provost. Jeff earned his Ph.D. in clinical psychology at UMaine in 1986 and joined the Department of Psychology as Director of the Psychological Services Center that year. He has made his career at UMaine rising through the ranks to Professor of Psychology.

In addition to serving as a faculty member, over his 30-plus years at UMaine, Dr. Hecker has always held one or more administrative positions. He served as Director of Psychological Services, Acting Director of Clinical Training, and chair of the Department of Psychology. In 2013, after six years as Dean of the College of Liberal Arts & Sciences, he moved into his current position as Executive Vice President for Academic Affairs and Provost.

Dr. Hecker’s scholarly work has focused on anxiety disorders and inappropriate sexual behavior. However, he has also published in sports psychology, health psychology, and professional issues in clinical psychology. He is very interested in professional ethics and has led professional development workshops in this area.

Dr. Hecker is a licensed psychologist who has maintained a small clinical and consulting practice throughout his career.


Steven B. Johnson is an Extension Professor and Extension Potato Specialist with the University of Maine where he has been employed for the past 28 years. Steve has a Ph.D. from the University of Florida, a M.S. degree from the University of Maine at Orono and a B.S. degree from the University of Wisconsin-Madison, all in plant pathology. He spent a six-month sabbatical leave in Australia working on potato diseases and a six-month sabbatical leave in New Zealand working on potato diseases. With his passion for international agriculture, he has been a volunteer scientist in Eastern Europe and in Central America. He has served as divisional president for the American Phytopathological Society and in various leadership committee positions in the Potato Association of America. Twice receiving the Maine Potato Board’s President’s Award, he is widely recognized nationally and internationally for his expertise in potato disease control. His research and extension efforts are focused on practical applications for disease problems. He is currently leading and cooperating in numerous regional and national grants in disease control covering several crops. His major responsibilities in Maine are potato diseases, but also has research and extension programs in barley, garlic, carrots, and onions.


Margaret Tuttle McGrath is an Associate Professor with a research and extension appointment in Cornell University’s Plant Pathology and Plant-Microbe Biology Section in the School of Integrative Plant Sciences.  Meg has a Ph.D. in plant pathology from Pennsylvania State University, a M.S. degree in Botany from the University of Vermont, and a B.A. degree in Biology from Carleton College.  Since graduating from PSU in 1988 she has been stationed at the Long Island Horticultural Research and Extension Center in Riverhead, NY.  Her extension activities include diagnosing disease problems for growers and extension specialists, and providing information on diseases through meeting presentations, articles, and web postings.  Research focuses on optimizing management of diseases affecting vegetable crops and herbs within organic as well as conventional production systems.  Activities include investigating fungicide resistance primarily in the cucurbit powdery mildew pathogen, monitoring occurrence of diseases, and evaluating management practices: resistant varieties, cultural practices including reduced tillage and mustard biofumigation, fungicides, biopesticides and other organic fungicides.  Her passion for agriculture and helping growers Meg credits to her long family farming history that started in 1632 in NH.


John Rebar is the Executive Director of the University of Maine Cooperative Extension. He is the leader of the largest outreach component of the University of Maine System. John has been with Cooperative Extension for 33 years and was named executive director in 2007. It was under John’s leadership that UMaine Cooperative Extension has focused its work in two areas: supporting the Maine Food System and the 4-H Youth Development program. For the first ten years of John’s career with UMaine, he was based in the UMaine Extension Somerset County office in central Maine. John has a bachelor’s degree from the University of Maine at Fort Kent and a master’s degree from the University of Vermont.


Gary Secor is a Professor in the Plant Pathology Department at North Dakota State University. His professional areas of work have been diagnosis and management of potato and sugar beet diseases, and variety development of potatoes. He served as interim director of the potato breeding program at NDSU for three years. His work has concentrated on seed treatment, fungicide resistance management of Cercospora leaf spot of sugar beet, post-harvest Fusarium dry rot, blemish diseases of potatoes, zebra chip, Dickeya and disease free seed potato production. He teaches graduate and undergraduate classes, has mentored numerous graduate students, and is a frequent speaker at grower meetings in the US and internationally. He is the recipient of the Eugene R. Dahl Excellence in Research from NDSU in 2010, the Meritorious Service Award from the Northern Plains Potato Growers Association in 1996, the Distinguished Service Award from the sugar beet industry of MN and ND in 2012, the Meritorious Service Award from the National Potato council in 2014, and Honorary Life Membership in the Potato Association of America in 2015. He completed a developmental leave at the National Potato Center in Remehue, Chile in 2008. He is a native of Bozeman, Montana, and received both his BS and MS degrees from Montana State University. He received his PhD degree in Plant Pathology from the University of California, Davis in 1977.


Ian Toth has worked at the James Hutton Institute in Dundee, Scotland for over 20 years with a research focus on Pectobacterium and Dickeya, which he has studied since beginning his PhD at the University of Warwick in 1987. During this time he has worked on understanding the bases of pathogenicity as well as the more practical aspects of blackleg and soft rot disease management.   In 2004 his group generated the first genome sequence for Pectobacterium, which led to a number of new discoveries that have helped to guide his research on potato production and disease management. He works closely with the potato industry and other Pectobacterium and Dickeya researchers worldwide to help coordinate research efforts and share knowledge. Over the last 6 years he has been Head of ‘Weeds, Pests and Diseases’ at the Institute and manages a £6m research portfolio funded by Scottish Government in the area of ‘Productive and Sustainable Land Management and Rural Economies’. He is also the secretary of the Scottish Society for Crop Research Potato Sub-Committee and is on the management committee for Potatoes in Practice (the largest potato field event in the UK held in Dundee each year).


Jan van der Wolf started his career as phytobacteriologist at Wageningen UR in 1986. Initially, he focussed on the development and evaluation of serological molecular based assays for diagnosis of soft rot Enterobacteriaceae (SRE). Later his research broadened and involved studies on the ecology and management of diseases caused by SRE, but also studies on the ecology of various other pathosystems, including Ralstonia solanacearum and Clavibacter michiganensis subsp. sepedonicus in potato, Pseudomonas in mushrooms, Clavibacter in tomato and Xanthomonas in cabbage and strawberry. He became coordinator of an EU project on bacterial ringrot and is still coordinator of an EU Euphresco project on SRE. He described RNA- and DNA-based methods for detection of (viable cells of) plant pathogenic bacteria, patented the use of an endophytic biocontrol strain (Serratia plymuthica) effective for biocontrol of plant pathogenic bacteria and conducted various studies on dissemination of pathogens and colonization of plants with GFP-tagged plant pathogenic bacteria. Most of his work is conducted in close collaboration with stakeholders in Dutch agriculture and horticulture. He is (co)author of more than 70 publications in peer reviewed journals.


Andy Wyenandt received his BS degree from Cornell University in 1996 and his MS (1999) and PhD (2004) in Plant Pathology from The Ohio State University. Since 2004, Andy has been the Extension Specialist in Vegetable Pathology for Rutgers University/New Jersey Agricultural Experiment Station located at the Rutgers Agricultural Research and Extension Center (RAREC) in Bridgeton, NJ. His research has focused on helping vegetable and herb growers in New Jersey and the surrounding mid-Atlantic region identify and manage important diseases and fungicide resistance development.

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