Investigation on the possibilities of in vitro regeneration of oregano (Origanum syriacum L. var. bevanii (Holmes) Ietswaart)

The aims of this research were to determine possibility of in vitro regeneration of Origanum syriacum L. var. bevanii from different explants as well as to investigate the essential oil components of donor plants, regenerats and the callus. In the research, the explants (apical bud, auxillary bud, stem none and leaf disc) from ten different ecotypes with high leaf yield and high essential oil content were cultured on the MS or B5 Medium containing different contentrations (0, 0.25, 0.5, 0.75 or 1 mg/l) of 2,4-D or NAA in combination with different concentrations (0, 0.5, 1.0, 1.5 or 2.0 mg/l) of BAP or Kinetin. Four weeks after culture starting, the cultures were transferred to the sub-culture medium with the same content with induction medium. After that, the cultures were transferred to the regeneration medium containing different contentrations (0, 0.1, 0.25 mg/l) of 2,4-D or NAA in combination with different concentrations (0, 0.2, 0.50, 1 mg/l) of BAP or Kinetin. ½ MS medium were used for rooting. MS medium with 1.5 mg/l BAP was determined as the most effective medium for multi shoots formation and plantlet regeneration from the apical buds or auxillary buds explants of Origanum syriacum L. var. bevanii. However single shoots with roots were obtained on MS or B5 medium with 1 mg/l NAA. Highest shoot regeneration ratio (36 shoots per explants) was obtained from the auxillary bud explants of the ecotype with number of 62/2 cultured on the medium containing 1.5 mg/l BAP. The averaged roooting ratio on 1/2MS medium without growth regulator was determined as %43.5. Highest callus induction was obtained from the leaf disc explants cultured on the medium with 1 mg/l 2,4-D. But the calli did not show any plant regeneration. Chromosome number of donor plants and their regenerats from the ecotypes of Origanum syriacum L. var. bevanii was determined as 2n=30. Essential oil components of donor plants, regenerats and the callus were different from each others.