Peroxidase and polyphenol oxidase were two kinds of redox enzymes. The activities of PPO and POD in flesh around wound of pear fruit were raised first and then decreased from 24 h (Fig. 4A and B). However, compare to oligochitosan, chitosan inoculation significantly enhanced the activities of POD and PPO in flesh around wound of pear fruit, especially to POD (Fig. 4A and B). Chitinase and b-1,3-glucanase are two kinds of pathogenesis-related protein. The CHI and b-1,3-glucanase activities in flesh around wound of control pear fruit increased with storage time, while chitosan and oligochitosan inoculation obviously enhanced the activities of both enzymes (Fig. 4C and D). Furthermore, oligochitosan inoculation was more effective than chitosan, for example, the activities of CHI and b-1,3-glucanase in oligochitosan- treated fruit after 48 h were almost 1.5-fold to those in control fruit.