Figure 1.

(A,B) Effect of foliar spray with 1.7 mM acibenzolar-S-methyl (ASM) and 1.1 mM methyl jasmonate (MeJA) on Psa infection in Actinidia chinensis (A,B). Treatments were applied 1 week before spray inoculation with a suspension containing 10⁹ cfu ml⁻¹ of Pseudomonas syringae pv. actinidiae (strain 10627). Plants were assessed 2 weeks later and the leaf spotting was recorded according to the following index, 0 = 0% leaf area, 1 ≤ 10%, 2 = 10–25%, 3 = 25–50%, 4 ≥ 50%. The data are presented as means ± standard error (n = 9) and the asterisk indicates a significant difference between the treatment and the untreated control (LSD = 0.53, P < 0.05). (C) Fluorescent stereomicroscopy of A. deliciosa leaves inoculated with GFPuv labeled Psa (strain CFBP7286). Inoculation was performed by cutting the leaf tip with scissor dipped in a bacterial suspension (10⁹ cfu ml⁻¹). The photos were taken 2 weeks after inoculation. Measuring bar = 2 mm.