Immunocytochemical Localization of Hydroxyproline-rich Glycoproteins in Tomato Root Cells Infected byFusarium oxysporumf. sp.radicis-lycopersici: Study of a Compatible Interaction

(...) Cell walls of infected tomato root tissues, especially those harvested between 96 and 120 hr after inoculation, were markedly enriched in HRGPs. Accumulation of these glycoproteins appeared to be initiated after contact between the pathogen and the plant cell wall and to occur as a result of tissue damage. Although HRGPs were detected in wall appositions formed in the cortical area in response to infection, their restricted occurrence in walls of invaded cells showing signs of pronounced alteration suggests that accumulation of HRGPs in susceptible tomato plants is a late biochemical event. This supports the concept that early enhancement of HRGPs is a prerequisite to their efficiency in the protection of plants