In vitro propagation of Satureja thymbra L. (Lamiaceae): A valuable aromatic-medicinal native plant of the Mediterranean region

Satureja thymbra L. or savory is a highly threatened aromatic-medicinal endemic Mediterranean plant. Micropropagation can play a role in the protection of the natural eco­system. The disinfection protocol involved the immersion of shoot-tip explants in 70% alcohol (1 min) and 3% NaOCl (15 min) giving 61.18% success. The MS medium supplemented with 30 g/l sucrose and 7 g/l Plant Agar was optimum for the initial establishment stage (10-day culture, 92.31% proliferation) and afterwards supplemented extra with 0.5 mg/l BA for multiple shoot induction (5 weeks) (100% proliferation, 5.5 shoots 14.24 mm long). In rooting stage, 1 mg/l IBA gave the highest rooting (58.62%), 0.5 mg/l NAA the maximum root number (12.13) ​​and 0.1 mg/l IAA the largest root length (34.35 mm) (MS medium + 20 g/l sucrose + 6.5 g/l Plant Agar, 7 weeks) (Experiment No. 1). There was a progressive increase in rooting and shoot proliferation increasing the number of subcultures, being highest (100% rooting, 6 roots 70 mm long, 38.1% shoot multiplication, 2 shoots 30 mm long) in the 4^th subculture/ 4.5 weeks each in WPM medium (Experiment No. 2). Therefore, best rooting results (50-100%) were accomplished in 3 different composition media: (1 and 2) WPM medium + 20 g/l sucrose + 6 g/l Plant Agar (1st and 4^th subculture) and (3) MS medium + 30 g/l sucrose + 1 mg/l IBA + 7 g/l Plant Agar. The ex vitro survival of rooted microshoots after 4 weeks in the greenhouse mist (1 peat moss: 1 perlite) was 81.82%.