Ultrastructural determination of the early stage of conversion from root primordia to shoot primordia in vitro cultures of Solanum lycopersicoides Dun.

The object of the research were in vitro cultures of root primordia and the early stage of conversion from root to shoot primordia cultures (ESCRS) of Solanum lycopersicoides Dun. The cell ultrastructure of both culture types was studied in order to determine processes underlying the root and shoot morphogenesis type. It was found that a change of a morphogenesis type occurs together with reorganization of aggregate structure and the cell ultrastructural organization. There were 4 zones detected in root primordia culture aggregates (the surface, the starch, the division and the differentiation zone) and 3 zones in ESCRS culture aggregates (the surface, the inner and the differentiation zone). The differences were observed also in storage substances accumulated in a culture (starch in root primordia cultures; proteins, lipids and starch in ESCRS ones).