In vitro production of cell wall degrading enzymes by Phytophthora capsici Leon

The ability to produce cell wall degrading enzymes (CWDE) in liquid culture was investigated in several strains of Phytophthora capsici Leon. Differences in activity levels of polygalacturonase (PG), pectate lyase (PL), cellulase (Cx), xylanase (Xyl) and beta-glucosidase (beta-Gluc) were detected within the chosen set of strains. No correlation was found between degree of virulence and CWDE production, except in the case of beta-Gluc. Isoforms of these enzymes were detected and partially characterized. The potential role of CWDE in the pathogenesis of P. capsici seems to be rather limited, given their overall low or very low production level. Nevertheless, we cannot rule out the possibility that pectolytic and xylanasic enzymes (directly and/or through the products of their activity) are involved in the exchange of signals between fungus and plant. The possible pathogenetic role of beta-Gluc was also discussed.