The LPS-triggered second ROS burst is only partially dependent on LORE. A, The first rapid ROS burst after treatment with 50 μg/mL LPS in wild-type and lore mutant plants. ROS were monitored for 30 min with 400 μm luminol as a substrate. B, The second ROS burst after treatment with 50 μg/mL LPS in wild-type and lore mutant plants. ROS were monitored for 45 h with 200 μm luminol as a substrate. C, The second ROS burst after treatment with 25 μg/mL LPS in wild-type and lore mutant plants. ROS were monitored for 25 h with 200 μm luminol as a substrate. D, The second ROS burst after treatment with 25 μg/mL lipid A in wild-type and lore mutants. ROS were monitored for 45 h with 200 μm luminol as a substrate. E and F, Inhibition of primary root length in wild-type and lore mutant plants. Five-day-old seedlings were transferred to the indicated liquid media and the primary root length was measured 5 d after incubation. The data are shown as means ± se (n = 18). Asterisks indicate significant differences (Student’s paired t test: *P ≤ 0.05). All experiments were repeated twice with similar results.