Please cite this article in press as: Rioba, N.B., et al., Effects of nitrogen, phosphorus and irrigation frequency on essential oil content and composition of sage (Salvia officinalis L.). J. Appl. Res. Med. Aromat. Plants (2015), http://dx.doi.org/10.1016/j.jarmap.2015.01.003 ARTICLE IN PRESS G Model JARMAP-26; No. of Pages 9 Journal of Applied Research on Medicinal and Aromatic Plants xxx (2015) xxx–xxx Contents lists available at ScienceDirect Journal of Applied Research on Medicinal and Aromatic Plants j ourna l h om epa ge: www.elsevier.com/locate/jarmap Effects of nitrogen, phosphorus and irrigation frequency on essential oil content and composition of sage (Salvia officinalis L.) Naomi Boke Rioba a , Francis Musyoka Itulya b , Mwanarusi Saidi b , Nativ Dudai c,∗ , Nirit Bernstein d,∗ a Department of Horticulture, School of Agriculture and Biotechnology, University of Kabianga, Kericho, Kenya b Department of Crops, Horticulture and Soils. Faculty of Agriculture, Egerton University, Nakuru, Kenya c Aromatic, Medicinal and Spice Crops unit, ARO, Newe Ya’ar Research Center, Ramat Yishay, Israel d Institute of Soil Water and Environmental Sci., Volcani Centre, Bet Dagan, Israel a r t i c l e i n f o Article history: Received 13 September 2014 Accepted 28 January 2015 Available online xxx Keywords: Salvia officinalis Nitrogen Phosphorus Irrigation Essential oil Essential oil composition a b s t r a c t Essential oil produced by aromatic plants is affected by many environmental factors includ- ing nitrogen (N), phosphorus (P), and watering frequency. Salvia officinalis (sage) is an aromatic plant widely used in the food, medicine and cosmetic industries. We studied effects of N, P, and irrigation frequency on essential oil content and composition of sage. In a field experiment in a plastic tunnel N and P were each supplied at four rates (0, 40, 80, 120 kg N ha -1 ; 0, 30, 60, 90 kg P ha -1 ) and the plants were watered every 1, 2, or 4 weeks. The treatments did not affect essential oil content. Fifty-four compounds were identified in the essential oil. N and watering frequency affected the production of -pinene, and inter- active effects were noted for NxP on -and -thujones, and for Nx irrigation frequency on -thujone. Negative correlation was identified between 1,8-cineole and viridiflorol. The percentage of camphor was higher than the recommended threshold by ISO standard for trade of sage essential oil. © 2015 Elsevier GmbH. All rights reserved. 1. Introduction Sage (Salvia officinalis L.) is an evergreen woody shrub well known as a common medicinal and aromatic plant. It is used for fresh food consumption (Maisuthisakul et al., 2007), as a savory food flavoring either as dried leaves or essential oil (Lu and Foo, 2002), in herbal medicine (Khan et al., 2011) and in the cosmetic and perfume indus- tries (Lu and Foo, 2002). Numerous components such as ∗ Corresponding authors at: Institute of Soil, Water and Environmental Sci., Volcani Center, POB 6, Bet Dagan 50-20, Israel. Tel.: +972 506 220 707/+972 506 220 010. E-mail addresses: nativdud@gmail.com (N. Dudai), Nirit@agri.gov.il (N. Bernstein). monoterpenes (Couladis et al., 2002), diterpenoids and triterpenoids (Coisin et al., 2012) were isolated from sage and 1,8-cineol, camphor, -pinene, -pinene, -thujone, and -thujone were reported to be the main components of it’s essential oil (Bozin et al., 2007; Delamare et al., 2007). Essential-oil content and composition in aromatic plants is affected by environmental conditions (Dudai, 2005) including soil fertility and mineral nutrition (Dragar and Menary, 1995; Piccaglia et al., 1989; Schaller and Schnitzler, 2000; Singh et al., 1989; Thomas and Cracker, 1991). Macronutrients are considered to be the main soil factors influencing production of the volatile components (Dudai, 2005) and variations in micronutrient contents and soil sodicity, salinity, and texture also affect oil composition http://dx.doi.org/10.1016/j.jarmap.2015.01.003 2214-7861/© 2015 Elsevier GmbH. All rights reserved.