In vitro propagation of cherry birch (Betula lenta L.)

Abstract

An efficient procedure for the micropropagation and conservation of cherry birch (Betula lenta L.), an endangered species in Canada, is reported. The model utilizes in vitro proliferation of fresh and dormant buds from both greenhouse and mature trees. Various factors were evaluated to optimize the protocol, including plant growth regulators, type and concentration of carbohydrates, and the composition of basal salts. 6-benzylaminopurine was the most effective cytokinin for shoot multiplication, with an optimal concentration of 5 μM. Sucrose was a more effective carbohydrate source than glucose, with the highest multiplication rate occurring at 3% sucrose (w/v). Shoot multiplication was similar on Murashige and Skoog (MS) and Driver and Kuniyuki Walnut (DKW) basal salts, but significantly lower on Woody Plant medium (WPM). Culture media with half-strength DKW basal salts and 20 μM indole-3-butyric acid was found to be the best for rooting (80%). Rooted plantlets were acclimatized to the greenhouse environment with a 37% survival rate. The micropropagation technology developed in the study offers excellent opportunities and tools for rapid replenishment of cherry birch trees in their natural environment, long-term conservation, and provides a platform for further research of this nationally endangered species.