Doi: http://doi.org/10.17584/rcch.2019v13i1.7897 REVISTA COLOMBIANA DE CIENCIAS HORTÍCOLAS - Vol. 13 - No. 1, pp. 120-129, January-April 2019 Content and composition of essential oil in lemon balm (Lippia alba (Mill) N.E.Br.) grown with ammonium and nitrate in light environments Aceite esencial de cidrón ( Lippia alba (Mill) N.E.Br.) cultivada con proporciones de amonio y nitrato y entornos de luz JANDERSON DO CARMO LIMA 1, 4 ANACLETO RANULFO DOS SANTOS 2 ALINE DOS ANJOS SOUA 2 MARCELO BATISTA DOS SANTOS 3 PERICLES BARRETO ALVES 3 Lemon balm plants in experiment. Photo: J.C. Lima ABSTRACT Medicinal plants have great potential for the production of phytocompounds, which are used for various purposes, mainly in drugs and cosmetics. The aim of this study was to evaluate the essential oil from Lippia alba cultivated with ammonium (NH 4 + ) and nitrate (NO 3 - ) under light environments. The plants were sub- jected to five ratios of NH 4 + : NO 3 - with nutritious solutions and four light environments (red, aluminet and black mesh, and full sun). The experiment design was entirely randomized with a 5×4 interaction and five repetitions per treatment, totaling 100 experiment units. The seedlings were transplanted to 6 dm 3 plastic pots containing a mixture of washed sand + vermiculite at a ratio of 2:1. At 120 days after application of the treatments, the following parameters were evaluated: yield, content and composition of essential oil. The extraction was performed with the hydrodistillation method using drag of steam for a period of 2 hours. Nine compounds were found in the essential oil, of which neral and geranial represented 90% of the blend. Carvone was only found in the treatment with plants grown under the red mesh and with the 50:50 ratio of ammonium and nitrate. Additional key words: essences (essential oils); artificial light; nitrogen; secondary metabolism. 1 Universidade Estadual de Feira de Santana, Doutorando em Recursos Geneticos Vegetais, Feira de Santana (Brazil). ORCID Lima, J.C.: 0000-0002-7564-5044 2 Universidade Federal do Recôncavo da Bahia, Centro de Ciencias Agrarias Ambientais, Cruz das Almas (Brazil). OR- CID Santos, A.R.: 0000-0003-4629-3948; ORCID Soua, A.A.: 0000-0003-1522-574X 3 Universidade Federal de Sergipe, Sao Cristovao (Brazil). ORCID Santos, M.B.: 0000-0002-3501-4475; Alves, P.B.: 0000- 0002-8955-9614 4 Corresponding author. janderson_ufrb@yahoo.com.br