Impact of Nitrogen Levels on the Growth and Medicinal Properties of Periwinkle (Catharanthus roseus) in an Inceptisol of Varanasi, India

Aims: Periwinkle (Catharanthus roseus), is a perennial herbaceous, belongs to the Apocynaceae family. The medicinal poperties are more economically important than the yield of the plant. Nitrogen is the main nutrient affect the medicinal properties of the plant. The main aim of this study was the evaluation of the effects of nitrogen on growth of the Catharanthus roseus and the presence or absence of alkaloid vinblastine.

Place and Duration of Study: The experiment involved a pot experiment conducted during Rabi season of 2021-2022 in the net house, at Agricultural Research Farm of the Institute of Agricultural Sciences, Banaras Hindu University, Varanasi.

Methodology: The experiment was laid out in a completely randomized design (CRD) with five nitrogen levels i.e. Control (RDF), 2.5g urea/pot, 5.0g urea/pot, 7.5g urea/pot and 10.0g urea/pot in three replications. Plants fed with recommended dose of P: K (40:40) and nitrogen fertilizer according to treatment.

Results: Higher dose of nitrogen i.e., 10.0 g/urea (T5) showed the greatest increase in plant height, number of branches, flowers per plant and SPAD value while number of leaves per plant was maximum at 2.5 g urea/pot (T2) whereas the lowest growth were exhibited in control treatment (T1). The presence or absence of vinblastine was tasted by Thin Layer Chromatography (TLC) and the result showed that at all the levels of nitrogen treatment, vinblastine was present except at control treatment (T1) till a month after transplanting.