Original Article In vitro Regeneration of Taverniera Abyssinica A. Rich: A Threatened Medicinal Plant

Abstract

In vitro germination, callus induction and plant regeneration has been established for dingetegna, Taverniera abyssinica. The best in vitro germination of seeds and vigorous seedlings growth as a prerequisite for the development of tissue culture methods was obtained on Murashige and Skoog medium supplemented with 12 g 1-1 phytoagar without sucrose. Light green compact calli from node, petiole and shoot meristem explants were efficiently induced on Gamborg medium containing 0.90 or 1.80 µM dichlorophenoxyacetic acid (2,4-D) combined with 2.22 µM 6-benzylaminopurine (BAP), and supplemented with 30 g 1-1 sucrose and 5 g 1-1 phytagel. Callus initiation from shoot meristems and nodes was faster and occurred with a higher frequency than callus initiation from petiole and leaf segments (P<0.05). A high frequency of shoot regeneration (100%) was obtained upon transfer of calli onto regeneration medium containing 8.88 µM BAP combined with 1.14 µM indoleacetic acid (IAA). Regenerated shoots were transferred to rooting medium, which turned out to be optimal when half strength B5 medium was supplemented with 9.84 µM indolebutyric acid (IBA). Upon transfer to glasshouse, 86% survived and grew vigorously. The development of in vitro regeneration protocol for T. abyssinica provides the possibility to preserve endangered germplasm from the increasingly devastating man-made environmental conditions. Moreover, the method established can be used for micropropagation and genetic improvement of this medicinally important species.