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Dr. Ploetz was born in Gastonia, North Carolina, but spent most of his youth in the Midwest. He received B.S. (Forestry) and M.Sc. (Plant Pathology) degrees from Purdue University and a Ph.D. (Plant Pathology) from the University of Florida (UF). After a post-doc at the North Florida Research and Education Center in Quincy, UF, he joined the Plant Pathology Department at the Tropical Research and Education Center (TREC), UF, in Homestead in 1986, where he was promoted to full professor in 1996. He has a research and teaching appointment at TREC, where his primary research responsibilities are on the etiology, epidemiology and management of diseases of crops that are produced in South Florida.

Dr. Ploetz is an authority on diseases of tropical fruit crops and has written several hundred scientific and popular articles on these topics, including four books (two with APS Press). He has made significant contributions to our understanding of the ecology, origins and relatedness of the causal agents and the diseases they cause.

Much of his work has been on banana diseases, especially Fusarium wilt. He introduced new banana germplasm to South Florida and evaluated its response to local vegetative compatibility groups (VCGs) of the pathogen, Fusarium oxysporum f. sp. cubense (Foc). He was the first to study global populations of Foc and with colleagues showed that Foc is polyphyletic; this was the first example of multiple evolutionary origins for a Fusarium wilt pathogen. In 1989, he discovered a new strain of Foc (tropical race 4, TR4), which now devastates production of the important Cavendish subgroup in the Eastern Hemisphere and threatens export trades in the Americas that rely on these cultivars. As it spreads, TR4 could cause dramatic changes in where and how bananas are produced for international trade. With colleagues, Randy has raised awareness and educated producers in the Americas about TR4.

Dr. Ploetz studied the physiological impacts of Phytophthora root rot (PRR, caused by P. cinnamomi) and flooding on avocado, Persea americana, and dissected the profound and rapid detrimental interaction that occurs when trees are exposed to both factors. In half-sib populations from the national germplasm repository of this crop in Miami (USDA-ARS), he also showed that PRR tolerance was greatest in progeny from specific female parents of the West Indian race of the host (P. americana var. americana). Unfortunately, it is the West Indian race that is most susceptible to laurel wilt, a lethal disease caused by an ambrosia beetle symbiont, Raffaelea lauricola. Dr. Ploetz has studied the epidemiology of this unusual disease, examined spread within and among trees and lateral movement of the pathogen among different new encounter ambrosia beetles; with entomologists and chemical ecologists, he investigates the emergence of some of these insects as vectors in the avocado pathosystem. He also studies the physiological and anatomical responses of the host to infection by R. lauricola, and management of the disease with diverse chemical and cultural measures. With colleagues, he developed a remote sensing technique for early detection of the disease, studied its spatial distribution in wild habitats and avocado orchards, and helped develop a taxon-specific PCR technique to identify the pathogen. He has been the project director for two recent NIFA SCRI projects on laurel wilt of avocado (ca $5.5 million).

Randy researches several destructive diseases of mango, Mangifera indica. Malformation is caused by different species in the Gibberella fujikuroi species complex, most importantly Fusarium mangiferae. He was the first to examine infection of the host by this pathogen, and developed a PCR diagnostic protocol that is still widely used for its detection. With colleagues, he described another new species that causes malformation, F. mexicanum, and helped confirm another species, F. pseudocircinatum, as a causal agent. With colleagues, he described a new, lethal mango pathogen in the Middle East, Ceratocystis manginecans (cause of sudden decline), and determined that different phylogenetic species of Colletotrichum cause post-harvest anthracnose on fruit; in the latter work, C. asianum was shown to be the only species capable of latently infecting fruit and causing blossom blight and leaf anthracnose.

Dr. Ploetz has visited over 60 countries on consultancies, to speak at scientific meetings, and to advise students and research projects. He has mentored 35 Ph.D. and 5 M.Sc. students, and 5 postdoctoral associates in the US and overseas. Randy is interviewed often on the impacts that diseases have on tropical crops. He has appeared on the Discovery Channel, and NPR Canada, Ira Flatow’s “Science Friday,” “Living on Earth,” and the “Diane Rehm Show” on NPR, as well as in Popular Science, Scientific American, New Yorker, Quartz/Atlantic magazine, The Independent, CNBC and other print and online media. He received the UF Research Foundation Professorship Award in 2004, the SPP Award in 2011, and APS’s Excellence in International Service Award in 2008.

Ploetz is an ad hoc reviewer for scientific journals, and has served professional societies and the University of Florida in diverse capacities. For the APS he has been a member of the Advisory Board and the Director of the Office of International Programs, a Senior Editor and Editor-in-Chief of APS Press, and a member of the Office of Electronic Communications, APS Council, the APS Financial Advisory Committee, and the APS Publications Board. He served as an associate editor for Phytopathology, and on APS committees on Classics, Forest Pathology, Mycology, Tropical Plant Pathology, and Soil Microbiology & Root Disease. He is a former president of the Florida Phytopathological Society and is the founding editor of the newsletter of that society. He is a former vice-president and managing editor for refereed papers for the Florida State Horticultural Society. Because of his excellence in research on tropical crops, training of numerous students and postdocs and international service, Dr. Randy Ploetz is most deserving of the APS Fellow award.