Almeida, Brígida Resende Assis, Rafael Marlon Alves de Leite, Jeremias José Ferreira Carvalho, Alexandre Alves de Botrel, Priscila Pereira Figueiredo, Felipe Campos Bertolucci, Suzan Kelly Vilela Pinto, Jose Eduardo Brasil Pereira
Doses and sources of organic fertilization influence biomass, volatile chemical composition, and phenolic compounds in Lippia gracilis
Lippia gracilis has emerged as one of the most important medicinal plants of the genus. Organic farming systems are currently growing substantially, aiming to obtain sustainable and economically viable plant production. Thus, the objective of this study was to assess the effect of different doses and sources of poultry manure on biomass production, photosynthetic pigment levels, phenolic content and volatile chemical composition in L. gracilis. The experiment was conducted in a completely randomized design in a 2 × 4 factorial arrangement with two sources of poultry manure (quail and chicken) and four doses (0.0, 1.5, 3.0, and 6.0 kg/m2) in 10 l pots. Plants fertilized with quail manure at a dose of 1.5 – 3.0 kg/m2 accumulated more total dry weight, while for chicken manure, the highest total dry weight gains were observed at doses of 3.0 and 6.0 kg/m2. In the chemical analyses of the essential oil, the major chemical constituent identified in all treatments was carvacrol. However, the highest carvacrol content was observed in the control treatment. L. gracilis plants increase their biomass when grown with 1.5 kg/m2 of quail manure or 3.0 to 6.0 kg/m2 of chicken manure. However, fertilization reduces carvacrol levels.
Keywords: Alecrim da chapada, Organic fertilization, Growth indices, Chemical analysis, Essential oil