Tissue culture and organogenesis of Iranian mountain ash (Sorbus persica Hedl.)

Iranian mountain ash (Sorbus persica Hedl.) is one of the endangered species with great values in terms of soil conservation, climate stratification, medicinal properties, high resistance to frost, and importance of habitat for wildlife. Present research was conducted with the aim of achieving to an appropriate method of micropropagation of the species. Nodal segments were taken from stem axis of in vitro elongated plants. The segments were cultured on WPM medium, supplemented with 27 hormonal composition of BAP, IBA and TDZ. Then the resulting shoots were transferred to a media supplemented with various concentrations of IBA or NAA for rooting induction, and finally they were moved to a greenhouse. Percentages of regeneration of the explants were 98 -100%. The highest number of shoots was obtained by TDZ (0.23 μM) + IBA (0.1 μM) and BA (4.4 μM), the highest shoot length (5.2 cm) was obtained by TDZ (0.0 μM) + IBA (0.0 μM) and BA (4.4 μM) and the highest number of nodes (8) was achieved by TDZ (0.23 μM) + IBA (0.0 and 0.1 μM) and BA (2.2 and 4.4 μM). There was a significant difference between IBA concentrations in different treatments for rooting percentage. Maximum rooting percentage was 14.7% in IBA concentration of 5 μm. The rooted segments were successfully acclimated to greenhouse conditions. Results of the experiment showed that in the absence of BAP hormone, umber of shoots produced by the segments significantly were decreased for all of the tested treatments. Fifteen percent of the transferred explants to the rooting media produced one to three roots per explant.