Effects of urea supplementation and different substrates on the production of indole alkaloid reserpine in Catharanthus roseus plants.

Catharanthus roseus belongs to the Apocynaceae family and is known as an important medicinal plant that produces several valuable terpenoid indole alkaloids. Reserpine is an indole alkaloid utilized in the treatment of paranoia, schizophrenia, and hypertension. In this study, we aimed to examine the effects of different concentrations of urea fertilizer and substrates on reserpine production by C. roseus plants. These plants were cultivated in pots containing either soil-humus-quartz, soil-perlite-quartz, or sand-quartz and treated with urea (60, 100, and 120 kg ha − 1) for 12 days. The experiment was performed based on a completely randomized factorial design with three replications. Different physiological parameters and reserpine concentrations were measured. Overall, results showed that the soil-humus-quartz substrate and 60 kg ha − 1 concentration of urea led to superior physiological and growth parameters (i.e., number of leaves, root length, root biomass, shoot length and shoot biomass) and the highest reserpine concentrations (605.8 ± 4.3 μg g − 1). It seemed that the soil-humus-quartz substrate contained organic materials and microorganisms which contributed to the generation of three nitrogen sources (i.e., urea, nitrate, and ammonium), enhanced the secondary metabolic pathways, and led to the highest production of reserpine in C. roseus plants. Supplemental data for this article is available online at https://doi.org/10.1080/11263504.2021.1986587. [ABSTRACT FROM AUTHOR]