Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 5/15/2001
Publication Date: 6/1/2001
Citation: Avant, J., Curry, K., Smith, B.J. 2001. Anthracnose of strawberry I: Early ontogeny of colletotrichum fragariae. Phytopathology. 94:S4.
Technical Abstract: Strawberry anthracnose may be caused by several Colletotrichum spp. including C. fragariae. Host tissue is invaded by a penetration peg developing from an appressorium. The peg develops into hyphae infiltrating the host tissue by either a hemibiotrophic or necrotrophic mode of invasion. Several plant pathogens mask or modify potential elicitors, such as fungal wall chitin, perhaps to avoid host defenses, such as chitinase. The distribution of chitin in fungal walls can be identified with gold labeled wheat germ agglutinin, a lectin probe. The strawberry cultivar Chandler was inoculated with C. fragariae isolate CF-63. Tissue at appropriate stages during early infection was fixed and epoxy embedded for examination with light and electron microscopy. Ultrastructural observations of the chitin probe indicate that the inner layer of bilayered walls of conidia, germ tubes, and appressoria contain less chitin than unilayered invasive hyphae. The distribution of chitin in fungal walls of early invasive hyphae was similar to the distribution in late invasive hyphae and in the walls of fungi grown outside the host.