Figure 5

Exogenous application of β-aminobutyrate and niacin unto Chinese cabbage showed pathogenic tolerance and ROS/RNS generation. (a) and (b) 21 DAG Chinese cabbage were shown to have a higher immunity against Xanthomonas campestris pv. campestris (Xcc) (10⁸ c.f.u.) after treated with 100 μM and 200 μM BABA as compared to those treated with mock (distilled water). Red arrow denotes the necrosis symptom. (c) Chinese cabbages were shown to have higher ROS level in the form of H₂O₂ after half-hour and an hour exogenous treatment of both 10 mM and 20 mM niacin (d) Confocal-microscopic analysis showed Chinese cabbage treated exogenously with 10 mM and 20 mM niacin as compared to those treated with mock (distilled water) have a higher NO content in the root for both half-hour and an hour treatment. Quantifications of viable Chinese cabbage (d) were recorded from biological replicates of 10 Chinese cabbage and plotted against time (hours) with normal standard error. NO and H₂O₂ levels were measured from biological replicates of 6 Chinese cabbage and statistical analysis were performed with standard ANOVA comparing the marked column to mock treatment, where ns = non-significant; *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001.