Fig. 6

Detailed expression profiles of the genes in the major lignin biosynthetic pathway in the roots of black pepper. White and black columns refer to P. nigrum (susceptible) and P. flaviflorum (resistant), respectively. Three biological and technical replicates for each plant part were analyzed to ensure reproducibility and reliability. Error bars in the figures denote the standard error of expression levels from three biological replications. CK-8, CK-12, CK-24, CK-48, 8, 12, 24, and 48 on the x-axis refer to 8, 12, 24, and 48 h on control and 8, 12, 24, and 48 h after inoculation with P. capsici, respectively. The y-axis represents the relative expression level compared with ubiquitin. Each column represents the mean value plus SD (standard deviation) from three biological replicates. The different capital letters indicate significant differences at P = 0.05 level