Secreted chitinase involved in the degradation of chitin, a component of the cell walls of fungi and exoskeletal elements of some animals (including worms and arthropods). Participates in the infection process and directly acts in the penetration process of the host cuticle. Random endo-hydrolysis of N-acetyl-beta-D-glucosaminide (1->4)-beta-linkages in chitin and chitodextrins. Only transcribed when chitin is the carbon source. The promoter contains the consensus motif for the creA/crel/crr1 carbon catabolic repressor. Decreases the mortality of the host cotton stainer bug Dysdercus peruvianus after infection. Belongs to the glycosyl hydrolase 18 family. Chitinase class III subfamily.