Efficient plant regeneration via somatic embryogenesis and organogenesis from the explants of Catharanthus roseus

Abstract

High-frequencyplantregenerationofC. roseus cv. 'little bright eye' via somatic embryogenesis and organo- genesis from five out of six explants was standardized. Two factors were found to be important for regeneration: (1) the type of explants, and (2) the combination and concentrations of plant growth regulators. The highest regeneration percentage through somatic embryogenesis was obtained from mature zygotic embryo in MS medium supplemented with 7.5 μM of thidiazuron (TDZ). The mature embryo also regenerated efficiently via organogenesis in MS medium supplemented with either 2.5 μM TDZ or 5.3 μM α- naphthalene acetic acid (NAA) and 2.2 μM 6-benzylami- nopurine (BA). Hypocotyl and cotyledon did not induce somatic embryogenesis and organogenesis in TDZ-contain- ing medium but gave a maximum percentage of shoots in MS medium supplemented with 5.3 μM NAA and 2.2 μM BA. Stem nodes and meristem tips showed better regener- ation via organogenesis in the medium supplemented with NAA and BA and in lower concentrations of TDZ.