Randy Christopher Ploetz

Title - Professor

Department - Plant Pathology

Specialty - Tropical fruit diseases

Telephone - 305-246-7001 Ext. 321

E-mail - kelly12@ufl.edu

Program Website - http://trec.ifas.ufl.edu/ploetz-lab/


  • Ph.D. 1984: University of Florida, Gainesville, FL -- Plant Pathology
  • M.S. 1976: Purdue University, West Lafayette, IN -- Plant Pathology
  • B.S. 1974: Purdue University, West Lafayette, IN -- Forestry


  • Professor (1996 to present), University of Florida, TREC, Homestead, FL
  • Courtesy Professor (1993 to present), Florida International University, Department of Biology, Miami, FL
  • Associate Professor (1991 to 1996), University of Florida, TREC, Homestead, FL
  • Assistant Professor (1986 to 1991), University of Florida, TREC, Homestead, FL
  • Assistant-in-Plant Pathology (1984 to 1986), University of Florida, NFREC, Quincy, FL
  • Graduate Research Assistant (1980 to 1984), University of Florida, Department of Plant Pathology, Gainesville, FL


  • 95% Research
  • 5% Teaching

Areas of Expertise

  • Research is conducted on soilborne and foliar diseases of agricultural crops, all of which are important in South Florida and some of which are important nationally and globally. Work occurs on a wide range of fungal pathogens and the diseases they cause with a broad focus of understanding their nature and devising effective means for their management.

Active Projects

  • Developing phytophthora root rot-resistant rootstocks for avocado.
  • Examining the host range of Mycosphaerella fijiensis, a major banana pathogen in Florida and worldwide, and Moniliophthora perniciosa, cause of witches' broom of cacao.
  • The phylogeny and geographic origins of Fusarium mangiferae, cause of mango malformation, and M. perniciosa, and devising management strategies for the important diseases they cause.
  • Biology and management of various root diseases of tropical fruit and traditional vegetable crops.
  • Investigations on diseases of ornamentals.

Awards & Recognitions

  • Director, APS Office of International Programs, 2004-2007.
  • APS representative, International Society of Plant Pathology. 2005-2010.
  • University of Florida Research Foundation Professor Award, 2004.
  • Editor-in-Chief of APS Press (book publisher of the American Phytopathological Society) (2000 - 2003), chair of the APS Publications Board (2002 - 2003), and member of APS Council (2000 - 2003) and the APS Financial Advisory Board (2002 - 2003).
  • President of the Florida Phytopathological Society (FPS) (1994 - 1996) and founding editor of the FPS newsletter.
  • Former vice-president (1997) and managing editor for refereed papers (1998 - 2001) for the Florida State Horticultural Society (FSHS).
  • Frequent member of scientific and organizing committees for international symposia.
  • Served consecutive terms as chairman of the CGIAR (INIBAP) working group on Fusarium Wilt in the 1990s.
  • Interviewed frequently regarding research program by print media, radio and television.
  • Best paper award, Krome Memorial Section, FSHS, 2001.

Selected Publications

Books Edited

Book Chapters

  • Ploetz, R.C. 1992. Fusarium wilt of banana (Panama disease). pp. 270-282 In: Plant Diseases of International Importance, Volume III. Prentice Hall, Englewood Cliffs, NJ. 452 pp.
  • Ploetz, R.C. 1993. Fusarium wilt (Panama disease). pp. 149-158 In: Ganry, J. (ed.). Breeding Banana and Plantain for Resistance to Diseases and Pests. CIRAD/FLHOR. Montpellier, France. 393 pp.
  • Ploetz, R.C., and O. Prakash. 1997. Foliar, floral and soilborne diseases of mango. pp.281-325 In: Litz, R.E. (ed.) The Mango. CABI. Wallingford, UK.
  • Ploetz, R.C., and Pegg, K.G. 2000. Fusarium wilt. pp. 143-159 In: Jones, D.R. (ed.) Diseases of Banana, Abac< and Enset. CABI Publishing. Wallingford, UK. 544 pp.
  • Ploetz, R.C. 2001. The phylogenies and reproductive strategies of globally dispersed populations of Fusarium oxysporum f. sp. cubense. Pp. 133-142. In: Molina, G., Masdek, N., Liew, K.W., (eds.) Banana Fusarium Wilt Management: Towards Sustainable Cultivation. IPGRI. Rome.
  • Ploetz, R.C. 2001. Malformation: A unique and important disease of mango, Mangifera indica L. pp. 233-247. in: B.A. Summerell, J.F. Leslie, D. Backhouse, and W.L. Bryden (eds.). Fusarium: Paul E. Nelson Memorial Symposium. APS Press.
  • Ploetz, R.C. 2001. Diseases of tropical crops caused by Fusarium spp. pp. 295-309. in: B.A. Summerell, J.F. Leslie, D. Backhouse, and W.L. Bryden (eds.). Fusarium: Paul E. Nelson Memorial Symposium. APS Press.
  • Randy C. Ploetz. (2003) Diseases of Atemoya, Cherimoya, Soursop, Sugar Apple and Related Crops. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CAB International. Wallingford
  • Randy C. Ploetz, John E. Thomas and Walter Slabaugh (2003) Diseases of Banana and Plantain. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK.
  • Sepiah Muid, Randy C. Ploetz and Anthony Cooke (2003) Diseases of Carambola. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK.
  • Randy C. Ploetz, Howard Ohr, John Carpenter and Yaacov Pinkas (2003) Diseases of Date. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK.
  • Randy C. Ploetz (2003) Diseases of Mango. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK.
  • Denis Persley and Randy C. Ploetz (2003) Diseases of Papaya. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK.
  • Antonio de Goes, Barry Manicom, Randy C. Ploetz and Carlos Ruggiero (2003) Diseases of Passion Fruit. In: R.C. Ploetz (ed.) Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK.


  • Ploetz, R.C. 1991. Nectria haematococca causes sudden wilt of passionfruit in south Florida. Plant Disease 75:1071-1073.
  • Ploetz, R.C., Ramos, J.L., and Parrado, J.L. 1993. Periodicity of root and shoot growth in grafted avocado. Tropical Agriculture 70:248-251.
  • Ploetz, R.C. 1994. Distribution and prevalence of Fusarium subglutinans in mango trees affected by malformation in Florida. Canadian Journal of Botany 72:7-9.
  • Boehm, E.W.A., Ploetz, R.C., and Kistler, H.C. 1994. Statistical analysis of electrophoretic karyotype variation among vegetative compatibility groups of Fusarium oxysporum f. sp. cubense. Molecular Plant-Microbe Interactions 7:196-207.
  • Ploetz, R.C. 1994. Panama disease: Return of the first banana menace. International Journal of Pest Management 40:326-336.
  • Ploetz, R.C., Benscher, D., Vázquez, A., Colls, A., Nagel, J., and Schaffer, B. 1996. A re-evaluation of mango decline in Florida. Plant Disease 80:664-668.
  • Koenig, R.L., Ploetz, R.C., and Kistler, H.C. 1997. Fusarium oxysporum f. sp. cubense consists of a small number of divergent and globally distributed clonal lineages. Phytopathology 87:915-923.
  • Ploetz, R.C., Pegg, K.G., 1997. Fusarium wilt of banana and Wallace's line: Was the disease originally restricted to his Indo-Malayan region? Australasian Plant Pathology 26:239-249.
  • O'Donnell, K. Kistler, H.C., Cigelnik, E., and Ploetz, R.C. 1998. Multiple origins of the fungus causing Panama disease of banana: concordant evidence from nuclear and mitochondrial gene genealogies. Proceedings of the National Academy of Science USA 95:2044-2049.
  • Ploetz, R.C., Vázquez, A., and Haynes, J. 1999. Responses of new banana accessions in South Florida to Panama disease. Crop Protection 18:445-449.
  • Ploetz, R.C. 2000. Management of the most important disease of banana and plantain, black Sigatoka. Pesticide Outlook 11:19-23.
  • Ploetz, R.C., Benscher, D., Dorey, A.J., and Vázquez, A. 2000. The epidemiology, control and cause of sooty blotch of carambola, Averrhoa carambola L., in South Florida. Fruits 55:241-252.
  • Zheng, Qi , Ploetz, Randy C. 2002. Genetic diversity in, and development of a PCR assay for indentifying, the mango malformation pathogen. Plant Pathology 51:208 -216.
  • Ploetz, Randy C., Schnell, Raymond , Haynes, Jody L. 2002. Variable response of open-pollinated seeding progeny of avocado to Phytophthora root rot. Phytoparasitica 30:262-268.
  • Ploetz, Randy C., Heine, Gregor , Haynes, Jody L., Watson, Mari. 2002. An investigation of biological attributes that may contribute to the importance of Phytophthora capsici as a vegetable pathogen in Florida. Annals of Applied Biology 140:61-67.
  • Ploetz, R.C. 2004. Pythium splendens is an opportunistic pathogen of carambola, Averrhoa carambola. Mycopathologia 157:225-231.
  • Randy Ploetz, Raymond J. Schnell, Zhentu Ying, Qi Zheng, Cecile T. Olano and Elizabeth Johnson. 2005. Analysis of Genetic Diversity in Crinipellis perniciosa with AFLPs. European Journal of Plant Pathology 111:317-326.
  • Ploetz, R.C. 2006. Fusarium-Induced Diseases of Tropical, Perennial Crops. Phytopathology 96: 648-652.
  • Ploetz, R.C. 2006. Fusarium wilt of banana is caused by several pathogens referred to as F. oxysporum f. sp. cubense. Phytopathology 96: 653-656.
  • W.F.O. Marasas, R.C. Ploetz, M.J. Wingfield, B.D. Wingfield, and E.T. Steenkamp.2006. Mango Malformation Disease and the Associated Fusarium Species. Phytopathology 96: 667-672.