Micropropagation of Betula platyphylla ‘Fargo’ via Shoot Tip Culture and Regeneration from Leaf Tissues

Abstract

Abstract A micropropagation system was developed for mass propagation of ‘Fargo’® (Dakota Pinnacle™), a newly released cultivar of Asian white birch (Betula platyphylla). Shoot tips from the mature, 7-year-old tree were established on 75% strength Murashige and Skoog medium supplemented with 0.1 μM thidiazuron. The greatest shoot proliferation occurred on Woody Plant Medium supplemented with 2.2 μM benzyladenine (BA), solidified with 6.5 g/liter agar, and cultured at 24C (75F). Microshoots were rooted in vitro or ex vitro followed by establishment in the greenhouse. A system to regenerate plantlets from leaves of aseptically cultured shoots was also developed. The optimum conditions for shoot regeneration from leaves included a 2-week dark treatment before exposure to a 16/8 hour light/dark photoperiod, use of large and healthy leaf explants, and culture on the Woody Plant Medium containing 20.0 or 30.0 μM BA. The regenerated shoots proliferated on the micropropagation medium and were divided, and the resulting shoots were rooted ex vitro and acclimated in greenhouse conditions.