Micropropagation of mature Crataegus aronia L., a medicinal and ornamental plant with rootstock potential for pome fruit

The effects of culture media and cytokinin types on micropropagation of mature Crataegus aronia L. were investigated. Using single-axillary bud explants, the growth of cultures on MS, WPM, DKW and NRM containing 4.44 μM benzyladenine (BA) plus 0.05 μM indole-3-butyric acid (IBA), and on NRM containing thidiazuron, meta-Topolin (mT) or BA at 1.25, 2.5, 5.0 or 7.5 μM plus 0.05 μM IBA were compared. The culture medium had significant effects on shoot number and length. In comparison with MS, DKW and WPM, shoot production was greater on NRM (5.7 shoots per explant). Shoot production on MS, DKW and WPM (4.2, 4.2 and 4.1, respectively) were statistically similar to each other. Thidiazuron was detrimental to shoot formation and caused formation of rosette shoots and/or large callus to form on explants. In the presence of mT, only some of the explants developed into shoots. Benzyladenine was the only cytokinin that promoted both shoot proliferation and shoot elongation. Higher shoot numbers were obtained at 5.0 and 7.5 μM BA compared to lower concentrations of BA. Over 80% of microshoots rooted and rooted shoots were successfully acclimatized to ex vitro conditions.