Effects of media, carbon sources and cytokinins on shoot organogenesis in the Christmas tree scots pine (Pinus sylvestris L.)

Significant effects of seven basal media and three carbon sources (sucrose, glucose and fructose) on the induction of adventitious buds from embryos of Pinus sylvestris L. were observed. Moreover, hyperhydricity of explants and shoot regenerants was observed on basal media containing fructose, especially with half-strength Murashige and Skoog (MS), MS, and woody plant medium (WPM). Explants grown on a Gresshoff and Doy (GD) medium with sucrose produced the highest frequency of regeneration (81%) and with no hyperhydricity observed of developing adventitious shoots. Among three cytokinins tested including BA, BPA, and TDZ (at four concentrations each), 5 μM BA resulted in the highest regeneration frequency and mean number of adventitious shoots per embryo. Shoot regenerants were elongated after transfer to a GD medium containing 2 g-l^-1 activated charcoal and no growth regulators. After one month, rooting was induced on 10% of explants.