The expression of JA biosynthesis and signaling genes is consistent in iqm1 and cat2 mutants. A to C, Relative expression of the JA biosynthesis genes LOX2 (A), AOS (B), and OPR3 (C) after 3 d of infection with B. cinerea. Four-week-old leaves of wild-type, iqm1-1, cat2-1, and cat2/iqm1-1 double mutant plants were harvested for RT-qPCR. D to F, Relative expression of ERF1 (3-h treatment; D), MYC2 (1-h treatment; E), and PDF1.2a (3-h treatment; F) in 12-d-old seedlings after treatment with 50 µm MeJA. Total RNA was extracted at the indicated times. The transcript levels were quantified by RT-qPCR using ACTIN2 as a control. Independent biological assays were repeated three times, and similar results were obtained. Data from one representative replicate are shown. Values are means with sd from three technical measurements. Asterisks represent significant differences compared with Col-0 (Student’s t test, **, P < 0.01).