Random endo-hydrolysis of N-acetyl-beta-D-glucosaminide (1->4)-beta-linkages in chitin and chitodextrins. Expressed in leaves and at lower levels in roots, sheaths and meristems. Belongs to the glycosyl hydrolase 19 family. Chitinase class II subfamily. Lacks the chitin binding type-1 domain wich is one of the conserved features of the chitinase class I and class IV subfamilies.