Sexual and Vegetative Propagation of Hypericum empetrifolium Willd. subsp. empetrifolium

Abstract

Hypericum empetrifolium Willd. subsp. empetrifolium is an evergreen small shrub with small elongated decorative leaves and small yellow flowers in inflorescences, characterized for several pharmaceutical properties. In the present study, a first approach on the sexual and asexual propagation of this species was performed. Seeds, subjected to different types of pre-treatments [soaked in tap water; 50, 100 or 150 mg L-1 GA3 for 30 min and no treatment (control)], cultured for germination in petri dishes at 5, 10, 15, 20, 25, and 30 °C. Seed germination was only affected by temperature and the best result was obtained at 15 °C (71.2%). A significant interaction was found between pre-treatments and incubation temperature with the highest germination percentage (82%) occurred when the seeds soaked in 100 mg L-1 GA3 solution for 30 min and incubated at 20 °C constant temperature. Moreover, the germination speed was fastest from 20 to 25 °C (T50= 9.84 and 9.56 days for 20 and 25 °C, respectively). For asexual propagation, apical stem cuttings were taken at four different periods (4 seasons) and treated with IBA at concentrations of 0, 1000, 2000 and 3000 mg L-1. The cuttings were planted in a peat/perlite mixture 1:1 v/v in plastic square plug trays in order to study the rooting percentage. Winter was the most appropriate season for cuttings collection (100% rooting percentage) and dipping in 1000 or 2000 mg L-1 IBA (72% and 73%, respectively) was the best rooting hormone treatment.