VIEW ARTICLE

Etiology

Further Studies on the Relationship Between Cultural Characteristics and Pathogenicity in Ceratocystis ulmi. D. F. Hindal, Assistant professor of mycology, Division of Plant Sciences, West Virginia University, Morgantown, WV 26506; E. J. Harner(2), and W. L. MacDonald(3). (2)(3)Associate professor of statistics, Department of Statistics and Computer Sciences, and associate professor of plant pathology, Division of Plant Sciences, respectively West Virginia University, Morgantown, WV 26506. Phytopathology 69:108-111. Accepted for publication 2 August 1978. Copyright 1979 The American Phytopathological Society. DOI: 10.1094/Phyto-69-108.

Cultural variability among Ceratocystis ulmi isolates of known pathogenicity was studied. Four agar media were used, and radial growth, aerial mycelium production, formation of a striate radial growth pattern, and dry weight of mycelium production per square centimeter of colony area were measured. The more aggressive isolates generally grew faster, produced a striate radial growth pattern, and produced less dry weight of mycelium per square centimeter of colony area than less aggressive ones. Aerial mycelium production was associated with pathogenicity only on two of the media. Although some isolates within each pathogenicity type possessed combinations of cultural characteristics intermediate to those typical of either the more or less aggressive isolates, multivariate discriminant analyses on these cultural characteristics accurately classified the isolates in their respective pathogenicity types.