Effect of nitrogen and potassium fertilizer on growth, herbage and oil yield of irrigated palmarosa (Cymbopogon martinii [roxb.] wats. var. motia burk) in a semi-arid tropical climate

Abstract

Palmarosa (Cymbopogon martinii [Roxb.] Wats. Var. Burk., family, Poaceae) is grown as a perennial crop for production of high value essential oil, which finds application in high-grade perfumery and cosmetic products. A field investigation was carried out for 2 years (2002–2004) at the Central Institute of Medicinal and Aromatic Plants, Resource Centre, Bangalore, on a red sandy loam soil in the semi-arid tropical climate, to study the influence of different levels of nitrogen (0, 100 and 200 kg N ha−1 year−1) and potassium (0, 61.5 and 123.0 kg K ha−1 year−1) on growth, herbage, essential oil yield, oil content and quality of palmarosa (Cymbopogon martinii [Roxb.] Wats. var. Burk., family, Poaceae) grown under irrigated condition. During the period of investigations, palmarosa gave eight harvests in two years with 42.3–74.1 t ha−1 in total (total of eight harvests) herbage yield, and 218.3–382.1 kg ha−1 total essential oil yield. Application of nitrogen at 200 kg ha−1 year−1 increased the total herbage yield by 104.5% and total essential oil yield by 102.6% over control (no application of nitrogen). Addition of potassium (K) at 123 kg ha−1 year−1 enhanced the total herbage yield by 21.8% and total essential oil yield by 23.7% in comparison to no K application. The quality of the essential oil with 75–84% geraniol and 7.8–13.3% geranyl acetate was found to be good and readily accepted in the market.