VIEW ARTICLE

Genetics

Comparison of Isozyme Polymorphism in Races of Cochliobolus carbonum. K. D. Simcox, Postdoctoral research associate, USDA-ARS, Ohio Agricultural Research and Development Center, Wooster 44691; D. Nickrent(2), and W. L. Pedersen(3). (2)Assistant professor, Department of Plant Biology, Southern Illinois University at Carbondale, Carbondale 62901; (3)Associate professor, Department of Plant Pathology, University of Illinois at Urbana-Champaign, Urbana 61801. Phytopathology 82:621-624. Accepted for publication 27 February 1992. Copyright 1992 The American Phytopathological Society. DOI: 10.1094/Phyto-82-621.

Differences in isozyme polymorphisms between races of Cochliobolus carbonum were compared using starch gel electrophoresis techniques. Of 36 enzymes analyzed, isozyme polymorphisms were detected for aspartate aminotransferase, esterase, glucose-phosphate isomerase, leucine aminopeptidase, and mannitol dehydrogenase. Specific combinations of polymorphisms were found to be diagnostic of race pathotype for the isolates used in this study. Race 3 isolates of C. carbonum could be distinguished by the presence or absence of esterase and leucine aminopeptidase polymorphisms, which were not found in race 2 isolates. The extent of isozyme polymorphisms found in C. carbonum provides a useful tool to study the genetics and the evolution of a phytopathogenic fungi.