In vitro shoot regeneration from leaf explants of Echinops kebericho: an endangered endemic medicinal plant

Abstract

Echinops kebericho is a critically endangered endemic medicinal plant of Ethiopia. It is threatened due to over harvesting of its roots for medicinal purposes and from poor seed viability. This study aimed to develop a protocol for in vitro shoot regeneration from leaf explants of E. kebericho. The seeds were sterilized using ethanol followed by Clorox or calcium hypochlorite. Shoots from the germinated seeds were cultured on Murashige and Skoog (MS) medium containing different concentrations of α-naphthalene acetic acid (NAA) and 6-benzyl amino purine (BAP). Young leaves were cultured on MS medium containing different concentrations of BAP and NAA for shoot regeneration. For shoot multiplication, shoots were excised and cultured on MS medium containing different concentrations of BAP or kinetin (KIN) and NAA. The highest mean number of initiated shoots (4.00 ± 0.57) with 100% shoot induction was obtained on medium containing 1.0 mg/L BAP and 0.2 mg/L NAA. The highest shoot regeneration (33%) and shoot number (2.13 ± 0.06) were obtained on MS medium containing 2.0 mg/L BAP and 0.5 mg/L NAA. Medium containing 1.0 mg/L KIN and 0.2 mg/L NAA produced the highest number of shoots (4.67 ± 0.33) per explant. This protocol can be used for genetic improvement and conservation of this endangered species.

Keywords:

• Echinops kebericho
• in vitro regeneration
• medicinal plant
• conservation
• seed germination

Abbreviations:

• BAP – 6-Benzyl amino purine
• NAA – α-Naphthalene acetic acid
• IAA – Indolacetic acid
• KIN – Kinetin
• MS – Murashige and Skoog (1962)
• PGR – Plant Growth Regulator
• Ca(ClO)₂ – Calcium hypochlorite

Acknowledgements

Addis Ababa University is gratefully acknowledged for financial support. The authors acknowledge the Institute of Biotechnology, Addis Ababa University, and Ethiopian Public Health Institute for unreserved support and for providing seeds of Echinops kebericho, respectively. The authors also acknowledge Prof. Gary Wessel, Brown University, USA for editing the language.