In vitro organogenesis in Sophora toromiro from nodal segments

Sophora toromiro is an arboreal endemic to Chile and extinct in its natural state, this specie has problem for its conservation due to its difficult propagation. The present study aimed to determine the organogenic response of Sophora toromiro nodal explants under in vitro conditions using different culture media and plant growth regulators. Nodal segments were used as explants, and responded satisfactorily to shoots induction when they were grown in MS or WPM medium with addition of 6-benzyl amino purine (BAP), α-naphthaleneacetic acid (NAA), indole 3-butyric acid (IBA) or indole-3-acetic acid (IAA). The highest shoots number (3.5 shoots / explant) was achieved when the explants grew in WPM medium + 0.1 mg l-1 IBA. For roots induction, the explants were transferred to new culture medium, where the highest rooting percentage (42.1 %) was achieved by explants cultivating in MS medium + 0.5 mg l-1 NAA. This study provides new information for S. toromiro propagation and conservation.