Thomas A. Zitter was born in 1941 in Saginaw, MI, and received his B.S. degree in botany (1963) and his Ph.D. degree in plant pathology (1968) from Michigan State University. Zitter has served on the faculty of the University of Florida (1968–1979) and Cornell University (1979–present). Zitter has been a leader in plant pathology research and extension in service to the vegetable industry for nearly 40 years.
Zitter is one of the most respected vegetable crop pathologists in the United States today. His problem-solving research and his educational programs benefit vegetable producers in the northeast and across the nation. Walter R. Stevenson, professor of plant pathology and the Friday chair of vegetable production research at the University of Wisconsin, writes, “I strongly support the nomination of Dr. Thomas Zitter for the APS Fellow Award. He has provided a wealth of information to the vegetable industry that is helping to improve management and reduce losses. His Vegetable MD web site is clearly the best site available for science-based information regarding disease diagnosis, pathogens, and management information on vegetable diseases.”
Zitter is an exemplary extension educator. He is widely admired by the growers for his willingness to address their needs with timely, unbiased, and useful information. This was a large factor in Zitter’s selection as recipient of Cornell’s College of Agriculture and Life Sciences Award for Extension and Outreach in 2000, the Excellence in IPM Award from the New York State IPM Program in 2002, and the APS Excellence in Extension Award in 2002. Zitter’s U.S. colleagues have acknowledged his leadership in extension in several ways. He has served as a representative of extension plant pathology on CSREES departmental review panels at the University of Florida, North Carolina State University, Purdue University, and the University of Kentucky. He was elected and served as chair of the APS Extension Committee in 1987–1988 and he remains an active contributor to that committee. He has also served APS in numerous other ways.
Zitter’s applied research and extension programs are a continuum. Throughout his career, Zitter has contributed to applied knowledge in plant virology, conducting studies on maize white line mosaic and its satellite virus infecting sweet corn, on infection of pepper by cucumber mosaic cucumovirus, aimed at understanding the epidemiology of cucurbit viruses, and on potato Y potyvirus and potato leafroll luteovirus infection of potato. The pressing need to find immediate solutions for the control of fungal diseases lead Zitter in the direction of fungicide usage for potato seed piece treatments and foliar disease control of tomato early blight and several cucurbit diseases. His work with tomato early blight looked at ways to minimize fungicide sprays through the use of disease forecasting systems, alternative materials such as bicarbonates and mineral oils, use of foliar nitrogen sprays, and sprayer application technology including the use of air-assisted, electrostatic sprayers. His fungicide evaluations have provided necessary data for the approval of fungicides for the control of early and late blight of tomato. Zitter first described Ulocladium leaf spot on cucumbers in the United States and identified sources of resistant germplasm. He also identified new sources of muskmelon germplasm with resistance to gummy stem blight and utilized PCR specific probes to distinguish the gummy stem blight pathogen, Didymella bryoniae, from Phoma species. He described the distribution of Fusarium wilt of melon in New York and identified race 1 of the pathogen in the state for the first time. He showed that harpin protein (Messenger) reduced colonization of plants by insects. He utilized a biotype of Alternaria tomatophila identified in his lab as highly pathogenic on tomato to demonstrate that homozygous resistance is necessary in tomato varieties to combat this pathogen. He is currently working with others to incorporate Septoria leaf spot resistance into tomato varieties that also resist early blight and late blight. He is doing innovative research on the integration of least-toxic materials into the management of diseases in potato, tomato, and cucurbits.
Zitter has been a leader in developing disease reference materials and control recommendations. He served as editor for two disease compendia published by APS PRESS, Compendium of Tomato Diseases (two different editions) and Compendium of Cucurbit Diseases. He has authored more than 30 Cornell vegetable disease fact sheets and bulletins. Each of these publications has been received extremely well by diverse audiences. Zitter conceived and developed a comprehensive and attractive web site, Vegetable MD Online (http://vegetablemdonline.ppath.cornell.edu/), as a convenient tool for use by anyone interested in the diagnosis and management of vegetable diseases. The site, which includes more than 70 disease fact sheets and more than 500 illustrations in a photo gallery, has attracted worldwide attention. In 2001, Vegetable MD Online earned Zitter the American University Award for Educational Excellence in Web Page Development. In 2006 alone, the web site received more than 1.5 million “hits”, which places Vegetable MD Online in the top tier of popular science web sites. And Zitter continues to add valuable content to the site. The latest additions are diagnostic keys for tomato and cucurbits.
Another of Zitter’s legacies is the comprehensive program he has developed for plant disease management on cucurbits, integrating scouting, accurate diagnosis, cultural practices, variety selection, and decision guidelines for fungicide selection and application. He was senior editor for the New York Cucurbit IPM Scouting Procedures utilized in New York and surrounding states. In concert with colleagues, Zitter has organized several cucurbit workshops that were well attended by growers from several northeastern states. Zitter’s contributions to cucurbit production have also led to several invitations to address national and international audiences, including an international symposium on cucurbits in Adana, Turkey, and a melon symposium at APS Caribbean Division meetings.
Zitter is among the very best extension educators and applied researchers that the profession of plant pathology has produced. Zitter is highly deserving of the APS Fellow Award.