In Vitro Culture of Carnation (Dianthus caryophyllus L.) Focusing on the Problem of Vitrification

This study was conducted to evaluate the effect of plant growth regulators on in vitro shoot multiplication, vitrification and rooting of two carnation cultivars (Eskimo Mogr and Innove Orange Bogr). Isolated axillary buds were cultured on MS medium supplemented with different levels of Benzyl amino purine (BAP) or kinetin (Kin) in combination with 0.2 mg/l NAA and shoot multiplication and vitrification rate were tested. Then different concentrations of Naphthalene acetic acid (NAA) or Indole butyric acid (IBA) on root induction of regenerated shoots were surveyed. Shoot regeneration and vitrification were influenced by the cultivar, kind of cytokinin and its concentration. Eskimo Mogr produced more shoots in comparison with Innove Orange Bogr (6.17 and 3.83 shoots/explant, respectively). BAP-containing media had more shoot multiplication and vitrification than Kin and by increasing the concentration of cytokinin, shoot multiplication and vitrification increased. There was a negative correlation between plant height and internode length with vitrification (-77% and -85%, respectively). By considering the amount of multiplication and rate of vitrification for obtaining the highest number of normal shoots, MS medium containing lower concentration of BAP (1mg/l for Eskimo Mogr and 2 mg/l for Innove Orange Bogr) and 0.2 mg/l NAA is recommended. Rooting of regenerated shoots was dependent on the cultivar. The highest root percentage for Eskimo Mogr (83%) was achieved on the medium supplemented with 0.5 mg/l NAA, while for Innove Orange Bogr (98%) it was obtained on the medium containing 1.5 mg/l IBA.