VIEW ARTICLE

Response of Mitochondria from Corn Cytoplasms to the Pathotoxin of Helminthosporium maydis Race T. W. A. Krueger, Assistant Professor, University of Tennessee Agricultural Experiment Station, Knoxville 37916; L. M. Josephson(2), and J. W. Hilty(3). (2)Professor of Plant and Soil Science, University of Tennessee Agricultural Experiment Station, Knoxville 37916; (3)Associate Professor of Plant Pathology, Department of Agricultural Biology, University of Tennessee Agricultural Experiment Station, Knoxville 37916. Phytopathology 64:735-737. Accepted for publication 14 December 1973. DOI: 10.1094/Phyto-64-735.

The susceptibility of 26 corn cytoplasms to Race T of Helminthosporium maydis, and the response of mitochondria from these cytoplasms to the pathotoxin produced by the fungus was determined. Field tests showed that cytoplasms T, HA, and Q were susceptible to H. maydis and laboratory tests showed that mitochondria from these same three cytoplasms were susceptible to respiratory control ratio (RCR) decline in the presence of the pathotoxin. This indicates that the mitochondria are a likely site of pathotoxin effect and that cytoplasms with mitochondria susceptible to the pathotoxin will be susceptible to H. maydis.