Environ Exp Biol (2017) 15: 1–5

Effect of cytokinins on shoot proliferation of silver birch (Betula pendula) in tissue culture

Abstract

Micropropagation can be used as an alternative method for vegetative propagation of mature birch trees in order to increase effectiveness of breeding. In this study the optimal concentration of synthetic cytokinin 6-benzylaminopurine and naturally occurring cytokinin zeatin were determined for shoot proliferation of birch genotype Bau-40-17. Woody Plant Medium supplemented with 6-benzylaminopurine or zeatin at three different concentrations was used. The results showed that Woody Plant Medium supplemented with 1.0 mg L⁻¹ 6-bezylaminopuryne gave the best results for shoot multiplication. In the case of natural cytokinin zeatin, 1.0 mg L^–1 with addition of 0.1 mg L^–1 kinetin gave the best results, but proliferation rate was significantly lower than with synthetic cytokinin. The presence of cytokinin in the medium affected adventitious root formation and resulted in change of pH, which may have caused a positive effect on shoot multiplication rate.