Abstract
SUMMARY: Established histochemical methods were used to locate the activities of several acid and neutral hydrolases within cytoplasmic particles of Botrytis cinerea Fr. The Gomori procedure revealed acid phosphatase activity and this was used as a marker to show that these particles in fresh material were inactive until subjected to treatments which affected the permeability of lipid-protein membranes. This behaviour was interpreted as indicating that these particles may be comparable with the lysosomes of animal cells. It was shown that acid phosphatase, acid deoxyribonuclease II, β-galactosidase and several esterases were localized within these particles. Attempts to demonstrate β-D-glucuronidase activity were unsuccessful; aryl sulphatase activity was weak.