Nutrient encapsulation of nodal segments of an endangered white cedar for studies of regrowth, short term conservation and ethylene inhibitors influenced ex vitro rooting

Abstract

Studies on the conservation of white cedar (Tecomella undulata) are of worthwhile because of its potential advantages of various secondary metabolites, therapeutic usages combined with its endangered status. The present study was undertaken to investigate high efficiency regeneration system through encapsulated nodal segments of T. undulata excised from mature tissues. Highest regrowth and regeneration efficiency was achieved when the gelling matrix (3% sodium alginate in Murashige and Skoog’s (MS) basal medium) was supplied with 2.5μM BA (6-benzyladenine)+0.5μM IAA (indole-3-acetic acid) followed by their plantation on to the nutrient medium composed of MS+10.0μM BA with the production of 6.50±0.28 shoots/encapsulated nodal segment. The excised shoots were subjected to ex vitro rooting by exposing their cut ends to two different ethylene inhibitors [salicylic acid (2-hydroxybenzoic acid) and silver nitrate (AgNO3)] for 15min followed by their transfer to different potting substrates. Soilrite™ and vermi-compost potting substrates proved equally better for healthy root formation directly, under greenhouse conditions. Multiple shoot formation from a single encapsulated bead along with ex vitro rooting and direct acclimatization under greenhouse conditions supports this protocol to be more efficient, cost effective and less time consuming coupled with clonal propagation.