Figure 8From: Jasmonate-dependent induction of polyphenol oxidase activity in tomato foliage is important for defense against Spodoptera exigua but not against Manduca sextaInduction of PPO activity by mechanical wounding and insect oral secretions. PPO activity was assayed in wild-type leaves 72 hours after mechanical wounding (W) or wounding with addition of insect (M. sexta or S. exigua) oral secretions (W + OS). OS were diluted 1:1 in water and applied in their native state (OSn) or after heat denaturation (OSd). Data are shown for one of three independent experiments, representing the mean +/- SD of four biological replicates each including pooled leaf material from three plants. Different letters indicate significant differences in PPO fold-induction normalized to unwounded controls (C; One-Way-ANOVA (F5,18 = 12.534, P < 0.001) and post-hoc Holm-Sidak for multiple comparisons at P < 0.05).Back to article page