Figure 1.

Vindoline (A) and catharanthine (B) content in the leaves of Catharanthus roseus under different chitooligosaccharides treatments. The treatments were conducted with chitooligosaccharides of three molecular weights (1, 2 and 3 kDa) at four different concentrations (0.01, 0.1, 1 and 10 μg/mL). Vertical bars represent the standard deviation of three replicates. Different letters indicate statistically significant difference at p < 0.05.