Figure 3
Suppression of nonhost HR cell death and enhancement of bacterial multiplication by Pstab extracts in N. benthamiana . (A) Suppression of nonhost HR cell death by the ethyl acetate extract from Pstab culture supernatant (Pstab ext.). Pst T1 (2.1 x 106 CFU/ml) was infiltrated in N. benthamiana leaves, and photo was taken at 48 hpi. (B) Non-phytotoxin activity of Pstab extracts in N. benthamiana leaf. A high concentration of the Pstab extracts was used, 24 μl/ml instead of 6 μl/ml. Photographs were taken three days after infiltration. (C and D) Bacterial multiplications of nonhost pathogens P. s. pv. tomato T1 (Pst T1) and P. s. pv. glycinea (Psgly) after inoculation with Pstab extracts in N. benthamiana. Pst T1 (C) and Psgly (D) (3×104 CFU/ml) were inoculated with Pstab extracts, and the bacterial growth was measured. The experiment was repeated twice (three replications for each experiment) with similar results. Bars represent the means ± standard deviation (SD) (P<0.05, student’s t-test). (E) Temperature stability of Pstab extracts and suppression of nonhost HR cell death for three nonhost pathogens, P. s. pv. phaseolicola (Psp), P. s. pv. maculicola (Psm), and Pst T1. Pstab extracts were boiled (5 min/95°C) and co-infiltrated with the bacterial suspensions. Photographs were taken at 24 hpi.