VIEW ARTICLE

Cytology and Histology

Mode of Penetration of Sycamore Leaves by Gloeosporium platani. Dallas Seifers, Graduate student, Department of Plant Pathology and Weed Science, Mississippi State University, Mississippi State 39762; Vernon Ammon, associate professor, Department of Plant Pathology and Weed Science, Mississippi State University, Mississippi State 39762. Phytopathology 70:1050-1055. Accepted for publication 15 May 1980. Copyright 1980 The American Phytopathological Society. DOI: 10.1094/Phyto-70-1050.

The chronology of the infection process of the sycamore anthracnose fungus on seedling sycamore leaves was investigated by using scanning and transmission electron microscopy. Under laboratory conditions, spore germination on the leaf surface exceeded 90% after 6 hr of incubation. Growth on the surface was vigorous, of short duration, and random. Almost without exception, termination of germ tube growth occurred within 6 hr after inoculation and was characterized by development of prominent appressoria firmly attached to the leaf surface. Direct penetration of leaf surfaces by infection pegs emanating from appressoria was observed frequently.