VIEW ARTICLE

Cytology and Histology

Ultrastructural Examination of the Puccinia graminis-Darluca filum Host-Parasite Relationship. D. E. Carling, Graduate Research Assistant, Department of Plant Pathology, University of Missouri, Columbia 65201; M. F. Brown(2), and D. F. Millikan(3). (2)(3)Associate Professor, and Professor, respectively, Department of Plant Pathology, University of Missouri, Columbia 65201. Phytopathology 66:419-422. Accepted for publication 10 November 1975. DOI: 10.1094/Phyto-66-419.

Uredial sori of Puccinia graminis infected with Darluca filum were examined by transmission and scanning electron microscopy to determine the ultrastructural morphology of the host-parasite interface. We concluded that uredospores are penetrated directly by nonspecialized hyphae, with penetration largely dependent on the enzyme-producing capacity of the hyperparasite. In its association with P. graminis, D. filum may be described as a penetrating (nonhuastorial) destructive biotrophic mycoparasite.