in The Department of Plant Sciences

College of Agriculture and Life Sciences, Forbes Building 303,
P.O. Box 210036,
Tucson AZ 85721-0036
(520) 621-1977, FAX (520) 621-7186

Dr. Peter Cotty, Adjunct Professor
Division of Plant Pathology
College of Agriculture
Ph.D. (1984), University of Arizona

Cotty's lab homepage

e-mail: pjcotty@email.arizona.edu

Area of Interest:
Biology, physiology, and management of agriculturally important fungi. For over a decade my emphasis has been on the fungi that cause aflatoxin contamination.

Research Goals:
Aflatoxins are toxic chemicals that certain fungi produce during crop infection. Crops with high aflatoxin content have greatly reduced value. We seek methods to reduce of aflatoxin contamination. Our research is directed at both the causative fungi and the contamination process. Aflatoxin producing fungi are contained within Aspergillus section Flavi. We use variability within and among fungal communities to provide insights into many aspects of the ecology and biology of these fungi. Aspects addressed include the etiology and epidemiology of contamination, as well >as, adaptation, divergence, dispersal, pathogenicity, morphogenesis, and cellular regulation. We seek to understand forces that induce and maintain variability within fungal communities, as well as, forces that influence the composition of fungal communities. This knowledge is used to develop techniques to reduce the aflatoxin producing potential of fungal communities and thus the vulnerability of crops to aflatoxin contamination. A current major emphasis is a partnership with Arizona cotton producers and gins and the Arizona Cotton Research and Protection Council. This partnership seeks to reduce the risk of aflatoxin contamination by reducing the aflatoxin producing potential of fungi resident in agricultural fields through the application of atoxigenic strains of Aspergillus flavus. Other aspects of our work include characterization of factors that influence aflatoxin production, and identification of crop characteristics that dictate the level of susceptibility to contamination.

Selected Publications:

    Garber, R. K., and Cotty, P. J. 1997. Formation of sclerotia and aflatoxins in developing cotton bolls infected by the S strain of Aspergillus flavus and potential for biocontrol with an atoxigenic strain. Phytopathology 87:940-945.0

    Cotty, P. J. 1997. Aflatoxin producing potential of communities of Aspergillus section Flavi from cotton producing areas in the United States. Mycological Research 101:698704.

    Mellon, J. E., and Cotty, P. J. 1996. Purification and partial characterization of an elastinolytic proteinase from Aspergillus flavus culture filtrates. Applied Microbiology and Biotechnology 46:138-142.

    Elias, K. S., and Cotty, P. J. 1996. Incidence and stability of infection by double-stranded RNA genetic elements in Aspergillus section Flavi and effects on aflatoxigenicity. Canadian Journal of Botany 74:716-725.

    Mellon, J. E., Cotty, P. J., Godshall, M. A., and Roberts, E. 1995. Demonstration of aflatoxin inhibitory activity in a cotton seedcoat xylan. Applied and Environmental Microbiology 61:4409-4412.

    Cotty, P. J. 1994. Influence of field application of an atoxigenic strain of Aspergillus flavus on the populations of A. flavus infecting cotton bolls and on aflatoxin content of cottonseed. Phytopathology 84:1270-1277.

    Cotty, P. J., P. Bayman, D. S. Egel, and K. S. Elias. 1994. Agriculture, Aflatoxins, and Aspergillus. In: "The Genus Aspergillus: From Taxonomy and Genetics to Industrial Applications" FEMS Symposium No. 69, K. A. Powell, A. Renwick, and J. F. Peberdy, editors., Plenum Press. pp. 1-27.

    Egel, D. S., P. J. Cotty, and Bhatnagar, D. 1994. Variability among atoxigenic Aspergillus flavus strains in ability to prevent aflatoxin contamination and production of aflatoxin biosynthetic pathway enzymes. Applied Environmental Microbiology 60:2248-2251.

    Egel, D. S., P. J. Cotty, and K. S. Elias. 1994. Relationships among isolates of Aspergillus section flavi which vary in aflatoxin production. Phytopathology 84:906-912.

    Cotty, P. J., and Bayman, P. 1993. Competitive exclusion of a toxigenic strain of Aspergillus flavus by an atoxigenic strain. Phytopathology 83:1283-1287.

    Brown, R. L., Cotty, P. J., Cleveland, T. E., and Widstrom, N.W. 1993. The living embryo influences accumulation of aflatoxin in maize kernels. J. Food Protection 56:967-971.

    Bayman, P., and Cotty, P. J. 1993. Genetic diversity in Aspergillus flavus: association with aflatoxin production and morphology. Can. J. Bot. 71:23-34.

For more information contact:

Dr. Peter J. Cotty
University of Arizona
PO Box 210036, Room 303
Tucson, AZ 85721

Phone: 520-626-5049
Lab: 520-626-5704

last update: September 13, 2006
2004 The University of Arizona. All contents copyrighted. All rights reserved.