Lignin plays an important role in barricading the
pathogen from invading the plant through physical exclusion
(Bruce & West, 1989). The induction of PAL and PPO suggests that
1-MCP can induce resistance of jujube fruit against fungal pathogen.
On the other hand, the activities of b-1,3-glucanases and
chitinases in jujube fruit were not significantly enhanced by 1-
MCP (data not shown), indicating that 1 mL Ll 1-MCP is not able
to induce these two enzymes which can inhibit the growth of
fungi directly. CAT and SOD are important enzymes that can
protect cells from oxidative damage by scavenging reactive oxygen
species (ROS) (Lee & Lee, 2000; Scandalios, 1993)