John Franklin Leslie was born in Dallas, TX, in 1953. He received a B.A. degree in biology from the University of Dallas in Irving, TX, in 1975. He earned his M.S. and Ph.D. degrees in genetics at the University of Wisconsin-Madison in 1977 and 1979, respectively, under the direction of Tom Leonard. As a post-doctoral researcher, he worked for David Perkins at Stanford University. In 1981, he took a position with International Minerals & Chemical Corporation in Terre Haute, IN, as a research microbiologist studying the genetics and industrial uses of Fusarium graminearum. In 1984, he joined the faculty of the Department of Plant Pathology at Kansas State University. He was promoted to associate professor in 1990 and to professor in 1996. In 2006, he became head of the Department of Plant Pathology.
Leslie is a world authority on the genetics, taxonomy, and population biology of the genus Fusarium. Leslie and his colleagues have developed Fusarium into a tractable genetic research system for both basic science and economically important problems. They developed many of the genetic resources, techniques, and theoretical frameworks that are the essential infrastructure for genetic studies of these fungi worldwide. Leslie’s lab maintains a unique worldwide collection of more than 18,000 Fusarium strains that is an invaluable resource for those who work in this area. Leslie’s lab has become an important intellectual center of global Fusarium research. His recent book entitled The Fusarium Laboratory Manual is a compendium of identification details, essential media recipes and techniques, genetic maps, and suggestions for research strategies to approach common, and not so common, problems encountered in the field.
He has elucidated biological species within one particular group of the Fusarium genus, section Liseola. Using his large international strain collection and extensive mating experiments, he developed standard mating group tester strains that can be used to distinguish independent mating populations (biological species) within this section. So far, he has described four new species that are supported by cross-fertility tests and unique molecular markers. The broad acceptance of this new paradigm by the scientific community was used as the justification to retire the old name F. moniliforme and to erect many more new species names corresponding to the mating populations. His recognition of a new species (F. thapsinum) causing stalk rot of sorghum led to greatly improved testing of stalk rot resistance in the Kansas sorghum breeding program. This greater understanding of the population biology of Fusarium speciation quickly led Leslie and others to the conclusion that the production of important mycotoxins, including fusaric acid, fumonisin, and moniliformin, were limited to just a few of the biological species.
Another significant contribution was the development and application of the vegetative compatibility group (VCG) concept in this genus through the use of mutants altered in their ability to use nitrate. This technique led to the first papers defining the genotypic population structure of many members of this genus, including Gibberella fujikuroi, F. oxysporum, and F. graminearum. Leslie has followed up these studies with VCGs with similarly pioneering studies that use molecular markers to confirm the variation present in the field populations of these species. Leslie’s more recent contributions on Fusarium spp. and Cephalosporium spp. have used various molecular marker systems to elucidate the genetic diversity and population structure of the pathogens.
Leslie’s lab was the first to produce genetic linkage maps of species in the genus Fusarium. High density maps were produced for G. moniliformis and G. zeae, which were used to locate genes for important traits such as pathogen aggressiveness and mycotoxin production. The maps have recently served to anchor the physical genomic sequences of these two species. The linkage map of G. zeae was further used for a quantitative trait locus (QTL) analysis of aggressiveness in this pathogen. This was the first application of QTL analysis to a fungal pathosystem and identified the gene cluster responsible for the trichothecene mycotoxin chemotype (nivalenol or deoxynivalenol) as an aggressiveness factor on wheat.
In the international arena, he is a principal investigator on the International Sorghum and Millet Collaborative Research Support Program (INTSORMIL) with a focus on the grain mold and stalk rot complexes of sorghum and millet. Leslie has international collaborations with universities and government research groups in nine countries. One of the important outcomes of this research with South African colleagues was a better understanding of the production and toxicity of fumonisin, which is associated with esophageal cancer in adults and neural tube defects in newborn infants.
He has been an associate editor for Phytopathology and is a past member and chair of the APS Genetics Committee. He has also been an associate editor for Mycologia and was recently a two-term editor of Applied and Environmental Microbiology. He currently helps edit Food Additives and Contaminants and Plant Pathology Journal. Using his editorial experience, he developed a one-day scientific writing workshop to foster improved writing and editing skills for students and faculty in research institutions around the world. More than 6,000 people in 15 countries have attended these workshops.
In collaboration with colleagues at the University of Sydney, Leslie organizes an annual Fusarium Laboratory Workshop that is now held alternately in Manhattan, KS, and international sites. More than 350 Fusarium researchers from around the world have attended this series of workshops. In addition to these workshops, Leslie has also developed and taught courses in fungal genetics and population genetics.
In summary, Leslie is an internationally respected, highly productive, and well-rounded scholar. He is a world authority on the genetics, population biology, and taxonomy of the genus Fusarium. He has published 119 refereed journal articles and 22 book chapters and has written or edited six books. I believe that the combination of his research productivity and impact, international research collaborations, outreach efforts, and service activities make Leslie well-deserving for consideration as an APS fellow.