Localization of PlOS transcript and accumulation of JA in mechanically damaged lima bean leaves. A, Leaf damaged for 6 h by MecWorm during the first and second dark phases. See Figure 3D for details. Leaf segments were harvested 32 h after initiation of the first MecWorm damage. Sections 2 and 3 correspond to the first and the second nocturnal damage. Undamaged sections 1 and 4 served as control. Data represent the mean ± se (n = 3–4). Scale bar = 10 mm. Means followed with small letters are significantly different according to ANOVA followed by Scheffe's test (P < 0.05). B and C, Wound-induced expression of PlOS promoter∷GUS reporter gene constructs in leaves of 6-week-old Arabidopsis plants. Wounding by a needle (B) or MecWorm treatment (C) induced GUS activity after 2 h in areas in close proximity to wounding sites. Histochemical GUS assays were performed with two independent lines. Scale bar = 2 mm.