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American Phytopathological Society Award of Distinction
The Ohio State University Distinguished Scholar
10th Recipient of the Jakob Eriksson Prize in Plant Pathology
> Madden Highlights
My research is focused on understanding and describing plant diseases at the population level and relating disease intensity to crop losses and toxin contamination. I use mathematics and statistics to characterize disease epidemics in time and space with the goal of determining which biological and physical factors best predict: disease outbreaks, invasion, persistence, and the magnitude of disease spread. Previously, I developed approaches for assessing the threat of plant pathogens as bioterrorism weapons against U.S. crops. In the past, I have worked heavily on determining how rainfall affects splash dispersal of fungal spores. This basic work has increased our understanding of how fungal spores move within fields and between fields, and has shown how to better control some economically important diseases.
I do not have a specific crop responsibility, although I have worked a great deal with fungal diseases of strawberry and other fruit crops, fungal diseases of wheat, and virus diseases of different crops. I worked for 30 years on anthracnose of strawberry, caused by Colletotrichum acutatum, leather rot, caused by Phytophthora cactorum, and fungal diseases of grapes. For the past 15 years, I have conducted most of my basic and applied research on Fusarium head blight of wheat and barley, caused primarily by Fusarium graminearum. Research on head blight involves risk assessment and epidemic prediction, dispersal, environmental effects on epidemics, disease dynamics, crop loss assessment and prediction of toxin contamination, and development of optimal management methods. My research on disease epidemiology serves as a model for similar diseases on many crops. I also work in several interdisciplinary projects with other plant pathologists and plant scientists to better understand and manage plant diseases.
Statistical modeling is an important part of my research program. I am especially interested in the use of linear, generalized linear, and nonlinear mixed models for characterizing epidemics and evaluating control tactics. Meta-analysis has been a major theme of my program for the past 15 years. Besides applying previously developed approaches, new methods are being developed, especially for multi-treatment (network) meta-analysis. Overall, my program involves the following:
- Plant disease epidemiology, disease modeling, statistical analysis, and crop loss assessment, primarily aimed at Fusarium head blight of wheat, as well as other diseases.
- Influence of climate and environment on disease epidemics.
- Development of disease management strategies based on epidemiological theory and experimentation.
- Use of mathematical and statistical modeling to describe and understand the temporal and spatial dynamics of disease epidemics and forecast the risk of disease outbreaks.
- Quantification and prediction of crop losses and toxin contamination in relation to disease intensity and pathogen density.
- Sampling for disease incidence, including the development of new statistical methods for predicting sample sizes.
View impact story: Fusarium Head Blight Risk Assessment Tool
Who am I?
I was born and raised in Ashland, Pennsylvania, a small coal mining town in the eastern part of the state. I attended The Pennsylvania State University and received a B.S. degree in Biology/Botany in 1975. During my senior year I took the introductory course in plant pathology and fell in love with the field. I stayed at Penn State to earn M.S. and Ph.D. degrees in plant pathology. During my graduate education I developed a strong interest in the population biology of diseases and developed skills in computer science, mathematics, and statistics. After graduating in 1980, I came to Ohio State University (Wooster Campus) to work as a research scientist. I became an assistant professor in 1982, and was promoted to full professor in 1991. I was appointed Distinguished Professor of Plant Protection in 2008. Throughout my career I have been most interested in how plant diseases behave at the population (field and region) level, and have worked on the epidemiology of many diseases caused by fungi and viruses. I often use statistics and mathematics to represent epidemics and to evaluate control strategies. Besides my research and teaching at Ohio State, I am very active in the national professional organization of plant pathologists, the American Phytopathological Society (APS). Previously I was Editor-in-Chief of the scientific journal Phytopathology, and I served as President of APS from 1996-1997. Through my national activities I am trying to improve public understanding of the impact of plant diseases on food production worldwide, and draw realistic attention to the threat of plant pathogens to U.S. crops.
Teaching and Outreach
I teach a graduate level course in Plant Disease Epidemiology (PLNTPTH 0702), where we use the textbook I co-wrote with Gareth Hughes and Frank van den Bosch, The Study of Plant Disease Epidemics. I also co-teach Plant Disease Management (PLNTPTH 5603) and give lectures in other courses. I am very active advising graduate students and post-doctoral researchers.
I have taught workshops on statistics for many years to national groups but also overseas. Instructional material from some past workshops is available at https://u.osu.edu/agstatworkshops/ .
Most of my statistical and mathematical modeling has been done using commercial software, especially SAS, MINITAB, and MATHCAD. Many of my grad students and post-docs are experts in R software, although I prefer to use SAS, especially for mixed models. I have also written or prepared over the years computer programs for specialized analyses. Some programs (either specialized or based on commercial software) with reasonable documentation are available by going to my course website
(Plant Disease Epidemiology) and clicking on Downloads, or by going to the website that supports my mixed-model workshops (https://u.osu.edu/agstatworkshops/ ). At these sites, there are programs for meta-analysis, mixed model and generalized linear mixed model analysis, spatial analysis, nonparametric analysis, polynomial distributed lag regression, repeated measures analysis, factorials, and other applications. These programs are not intended for commercial use, and I make no guarantees that they will work correctly under all circumstances.
Honors and Awards
- Ciba-Geigy Agricultural Achievement Award, 1989, given by American Phytopathological Society (APS) [now called Syngenta Award]
- Distinguished Senior Research Award of the Ohio Agricultural Research and Development Center, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, 1990
- Distinguished Scholar Award of The Ohio State University, 1991
- Elected Fellow, American Association for the Advancement of Science (AAAS), 1992
- Gamma Sigma Delta (Ohio State Chapter) Research Award of Merit, 1994
- Outstanding Alumnus Award, The Pennsylvania State University, College of Agricultural Sciences, 1997
- Elected Fellow, American Phytopathological Society (APS), 1999
- Ruth Allen Award for Innovative Research, American Phytopathological Society (APS), 2003
- E. C. Stakman Award, University of Minnesota, 2005 (granted annually [or less often] to an individual of any country and nationality for outstanding achievements in agriculture)
- Fisher Lecturer, Rothamsted Research, England, March 2008
- Jakob Eriksson Prize and Gold Medal, 2008 (given internationally once every 5 years by the Eriksson Committee of the Royal Swedish Academy of Sciences for outstanding scientific work and engagement in plant pathology; presented at the International Congress of Plant Pathology [ICPP])
- R.R. Nelson Memorial Lecturer, The Pennsylvania State University, Department of Plant Pathology, 2014
- Award of Distinction, American Phytopathological Society (APS), 2019.
- Honorary Member of the British Society for Plant Pathology (BSPP), 2020