ADVENTITIOUS SHOOT REGENERATION FROM INVITRO LEAVES OF ADULT CAMELLIA-RETICULATA

Experiments were conducted with Camellia reticulata cv. Captain Rawes to develop an adventitious regeneration system. Leaves were taken from axillary shoot proliferation cultures in WPM medium that had been established from mature trees. They were sectioned, and then plated in Petri dishes on media containing various combinations of cytokinins and auxins; the best response was induced by 2 mg l-1 BA + 1 mg l-1 IBA. The shoots obtained were multiplied by axillary branching on WPM + 2 mg l-1 BA + 2 mg l-1 Z + 2 mg l-1 2iP + 0.01 mg l-1 IBA. There was no significant difference in multiplication coefficient (the product of the proportion of explants forming axillary shoots and the mean number of new segments per explant) between shoots of adventitious and axillary origin, but there was between the various types of explant used in the multiplication stage: shoot tips (ST1) and nodal segments (ns) of harvested shoots longer than 14-15 mm, and whole harvested shoots 7-10 mm long (ST2). The best results were achieved with ns and ST2 explants. Shoots of adventitious origin rooted very poorly in comparison with those of axillary origin under the same culture conditions.