A twenty-five-year old individual was used as a donor plant. For the adventitious bud formation, leaf segments obtained in vitro were cultivated on a medium containing microelements and chelate after Simola, trace elements and vitamins after Murashige and Skoog, 10 mg l^-1 zeatin ribozide, 30 mg l^-1 adenin, 20000 mg l^-1 sucrose and 6000 mg l^-1 agar.
For the rooting of microcuttings a half-strength MS medium containing different variants of auxins (0.3 and 0.5 mg l^-1 IBA; 0.3 and 0.5 mg l^-1 NAA; combination of 0.5 mg l^-1 IBA + 0.5 mg l^-1 NAA and a control medium without phytohormones) was used. The formation of adventitious root was studied morphologically and anatomically. Rhizogenesis was always preceded by callus formation for all auxin treatments. The percentage of rooted explants including controls, ranged 91.67 ± 1.89 % to 100,00 ± 0.0 %, which suggests a high rejuvenation rate.
An anatomical study of epoxy embedded material established that the auxin induced increased cambial activity resulting in new xylem and callus formation. Isodiametric meristematic cells appeared in the cambial zone or adjacent to it in the cortex. These cells gave rise to adventitious root primordia, which grew radially outwards between the sclerenchyma bundles of the cortex. Tracheid-like cells were formed at the base of the developing adventitious roots to provide a vascular connection between the root and the shoot.
The high air humidity and the kind of substrate were important factors for the successful acclimatization. The maximum plants' survival (98.3 ± 2.9 %) was obtained by opening the test tubes in the cultivation room for a period of 6 days, ensuring high air humidity for 14 days and utilizing a peat.