HOST-PARASITE INTERACTIONS BETWEEN SOLANU M-GILO RADDLI AND STEMPHYLIUM-FLORIDANUM HANNON AND WEBER - ULTRASTRUCTURAL ASPECTS

Penetration and colonization of Solanum gilo leaves by Stemphylium flo ridanum were investigated on experimentally infected plants. Microscop ic observations showed that fungal penetration occurred by stomatal ap ertures followed by invasion of the chlorophyllous parenchyma. Subsequ ently, important disruptions in the cellular organization started to d evelop in colonized tissues, as well as in cells located at short dist ances. As a reaction, the host seemed to build barriers to hyphal ingr ess by inducing necrotic areas enriched with phenolic compounds and ca llose.