Comparison of the genetic diversity (RAPD) of ex situ collections and natural populations of Naufraga balearica Constance & Cannon.

Naufraga balearica Constance & Cannon (Hydrocotyloideae) cultivated in the Botanical Gardens of Lyon, Brest and Porquerolles stem from two or three sh oots collected in Corsica in 1981. The genetic diversity of these plants wa s evaluated using RAPD markers (random amplified polymorphic DNA). It was c ompared with the diversity found in individuals collected from five natural sites in Majorca. Only a few patterns were present in the collections deri ved from the Corsican shoots. The plants kept in the Botanical Gardens appe ared to be of clonal origin: most individuals (81 %) showed a 'dominant pat tern'. In contrast, nearly all individuals sampled in the natural populatio ns of the Balearic Islands exhibited a unique pattern. The five populations appeared genetically distinct; the individuals probably resulted from cros s-fertilizations. The cultivated Corsican plants from Lyon, Brest and Porqu erolles appeared genetically closely related to the individuals sampled in the population of Cala San Vicente in Majorca. The spontaneity of this pale oendemic in Corsica was discussed. (C) 2000 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.