I Chet

Antagonistic Trichoderma spp. showed a chemotropic response toward the hyphae of Rhizoctonia solani. Attachment to its host fungus was either by hyphal coils, hooks or appressoria. Recognition is apparently due to the presence of lectin on the hyphae of the pathogenic fungi which binds to specific sugars on Trichoderma cell walls. Addition of galactose and fucose prevented this phenomenon. When this interaction occurred Trichoderma harzianum excreted B-1, 3glucanase and chitinase which caused a partial lysis of R. solani and S. rolfsii cell walls and enabled the antagonist to penetrate the host's cells and consume their cytoplasm. Similarly, the antagonist was able to penetrate sclerotia of J3. rolfsii and to lyse their contents.

Colloques de l'INRA no. 18