Propagation of Cunila galioides Benth.: a Medicinal and Aromatic Species Native to South Brazil

Abstract

Cunila galioides Benth. is an aromatic and medicinal plant widely used in the traditional medicine of South Brazil. The essential oil of one of its chemotypes has high citral contents, an oxygenated monoterpene used in perfumery, cosmetics, and food industries. The seeds of C. galioides have low germination percentages and there are few studies regarding its vegetative propagation. Thus, this study aimed to evaluate distinct indole-3-butyric acid concentrations (0 - control, 250, 500, and 1,000 mg∙L^-1) on the rooting of herbaceous cuttings of C. galioides and different methods (gibberellic acid, potassium nitrate, and stratification) to overcome a possible dormancy in the seeds. In vegetative propagation, the use of indole-3-butyric acid 250 mg∙L^-1 only increased root score relative to the control, and higher IBA concentrations had no effective response on the cuttings, not being necessary to use IBA in C. galioides cuttings. The most effective treatments regarding seed germination were gibberellic acid and potassium nitrate, with germination percentages of 57.8 % and 54.5 %, respectively; stratification was not effective in increasing the germination percentage of the seeds relative to the control.

Keywords:
cuttings; essential oil; germination; gibberellic acid; indole-3-butyric acid; potassium nitrate.

HIGHLIGHTS

• Methods to carry out the vegetative and sexual propagation of C. galioides were investigated.

• Cuttings can be used in vegetative propagation without the use of growth regulators.

• Gibberellic acid and potassium nitrate increased the germination percentage of the seeds.

• Seeds treated with gibberellic acid germinated earlier than the other treatments.