In vitro propagation of Hydrangea spp.

Hydrangea (Hortensia) is a highly popular ornamental plant for garden decoration, and now it is commercially produced for cut flower branches. For in vitro culture, Murashige and Skoog medium supplemented with BA (0.25 mg/L) and sucrose (30 g/L) was used. Culture conditions were 23 ± 1°C of temperature, light intensity of 35 μmol/m(2)/s P.P.F.D., and 16/8 h day/night photoperiod. Following shoot proliferation, the in vitro rooting frequency was 100% on a medium containing NAA 0.5 mg/L. However, 95% direct in vivo rooting was achieved by dipping microcuttings in a 5,000 ppm K-IBA solution which were transferred afterward to a glasshouse for acclimatization. After 21 days, fully acclimatized and well-established plants were obtained, suitable for commercialization. Furthermore, leaf fragments derived from in vitro plantlets were cultured for callus induction and adventitious shoot regeneration.