MICROPROPAGATION OF BETULA-UBER (ASHE) FERNALD

A method of propagation through nodal culture was developed for Virgin ia round-leaf birch, Betula uber (Ashe) Fernald. Nodal cultures of Vir ginia round-leaf birch had the greatest shoot elongation on woody plan t medium supplemented with 7.5 mu M benzyladenine and 2.9 mu M gibbere llin-3. Shoot elongation was significantly greater when benzyladenine was combined with gibberellin-3 than with benzyladenine alone. In conj unction with propagation, anatomical changes in cuticle and stomata we re examined at different stages of culture. Changes in stomatal length , stomatal density, cuticle thickness, and palisade parenchyma layers were noted during the various stages of culture. Propagation through n odal culture provides a feasible method by which Virginia round-leaf b irch can be propagated and maintained. The same techniques may be appl icable to other endangered hardwood species.