Role and significance of total phenols during rooting of Protea cynaroides L. cuttings
Phenolic compounds, which are known to regulate root formation, are found abundantly in difficult-toroot Protea cynaroides stem cuttings. In this study, analysis of total phenol content was carried out on blanched and unblanched cuttings to observe its fluctuation throughout the entire rooting period (120 days) and establish its relationship with root formation. Results showed that blanching significantly increased the total phenol content in the basal ends of the cuttings. The high total phenol content was associated with significantly higher rooting percentage and increased the number of roots formed. Blanching reduced the time needed for the cuttings to root sufficiently to be transplanted to the field by 30 days. Analyses of different parts of cuttings throughout the entire rooting period showed continuous increase in total phenols at the basal end, while decrease in total phenols was observed in the leaves.
Keywords: Etiolation, king protea, phenolic compounds, Proteaceae, root formation