Growing of tropical black sage and chemical composition of the essential oil

The objective of this study was to evaluate the influence of spacing and mulch on biomass production, chemical composition and production of essential oil of tropical black sage. A randomized block design was used in a 2×2 factorial scheme: two spacings (1.6 × 0.5 m and 1.0 × 0.5 m), with and without mulch, using five replications. In the end, the combination of spacing and presence and absence of mulch did not influence the height and diameter of the stem. However, it has influenced fresh matter: 8765.00 kg ha-1 (1.0 × 0.5 m, with mulch) and 6112.50 kg ha-1 (1.6 × 0.5 m, without mulch). The spacing 1.0 x 0.5 m was what provided higher dry matter (3052.14 kg ha-1). For the production of essential oil, the combination of spacing of 1.0 × 0.5 m, with mulch provided greater production (484.50 kg ha-1). Twenty-seven compounds were detected, of which 23 were identified, most of which were sesquiterpenes and monoterpenes. The α-pinene and the β-caryophyllene showed higher abundances in all samples, regardless of the treatment. The contents of α-humulene was sufficient to meet the requirements of the pharmaceutical industry. Thus, the alteration in soil spacing and mulch influences the production of essential oil and biomass, but it does not influence the relatives amount of the α-humulene and of the β-caryophyllene.