In Vivo and in Vitro Comparative Ultrastructural Studies of Ruscus Aculeatus L. Phylloclade Cells

A comparative study of the Ruscus aculeatus phylloclade cells structure and ultrastructure of plants belonging to the native habitat and in vitro culture are presented in the paper in order to establish an adequate protocol for ex situ conservation. In our experimental conditions no anomaly of the phylloclade cells ultrastructure has been observed. Some interesting modifications appeared at the plastidial system that are polymorphic as well as at plastoglobuli level that could represent adaptative modifications, but not genetic alterations. The in vitro experimental protocol, previously established by us for in vitro propagation that requires plants indirect regeneration, via callus, on the MS basal nutritive medium supplemented with 1 mg/l NAA and 5 mg/l BAP may be considered an adequate possibility for medium-term conservation of this species.