Adventitious Shoot Initiation in Serially Subcultured Callus Cultures of Solanum laciniatum

Abstract

Summary Callus cultures established from leaf expiants of Solanum laciniatum Ait. produced numerous adventitious shoots on a standard regeneration medium, consisting of MS basal medium supplemented with 2.25 mg·l -1 benzyladenine (BA) and 0.2 mg·l -1 indolebutyric acid (IBA). A loss of this shoot forming capacity was observed after repeated subculture, and was accompanied by an increase in nuclear DNA content. Attempts to restore caulogenic competence to old cultures by altering the type and/or concentration of growth regulator or the nutritional status of the regeneration medium were unsuccessful, though partial restoration was possible by extending the incubation time. Regeneration of plantlets was achieved by transfer of the excised adventitious shoots to hormone-free medium.