Differential degradation of apple cell walls in vitro by enzyme extracts from Botrytis cinerea and Glomerella cingulata

Abstract Growth and associated glycosidase enzyme production and activity of Botrytis cinerea and Glomerella cingulata were compared in vitro using apple cell walls as a carbon source. In liquid culture, the growth of the two pathogens was similar. Both fungi produced α- l -arabinosidase but β- d -galactosidase activity was higher in B. cinerea . In vitro degradation of apple cell walls by enzyme extracts from liquid cultures of G. cingulata was greater than for B. cinerea . After 24 h of incubation, the G. cingulata extract solubilized 69% of the total cell wall neutral sugar and 78% of the total uronic acid, while the B. cinerea extract solubilized only 43% of the neutral sugar and 37% of the uronic-acid-containing wall polymers. The neutral sugar composition of the residue remaining after degradation (the products left after the activity of the respective fungal enzymes) differed between the two fungi.