ANALYSIS OF POPULATION GENETIC-STRUCTURE AND VARIABILITY USING RAPD MARKERS IN THE ENDEMIC AND ENDANGERED LIMONIUM-DUFOURII (PLUMBAGINACEAE)

Limonium dufourii (Plumbaginaceae) is a triploid species, with apomict ic reproduction, endemic to the east mediterranean coast of Spain, whe re it is present in only six populations with a few individuals in mos t of them. L. dufourii is included in the Red List of Endangered Speci es by the IUCN. Genetic variation and population structure in this spe cies has been studied using RAPDs, Twelve different primers provided 1 24 reliable bands olf which 33 were polymorphic among the 165 individu als analysed. Those polymorphic bands were able to define 44 different patterns, of which all but six were present in only one population. S everal methods for statistical evaluation have been used for intra- an d interpopulation analysis of genetic variability. Relationships among patterns have led to the identification of four main clusters. Two of them show a perfect correspondence to the population of origin of tho se individuals that present them (Cullera and Torreblanca), and the ot her two (Groups A and B) include patterns found in individuals coexist ing in the same populations (Marjal del Moro populations) and in El Sa ler. Most of the variation found in this species is due to differences among populations as shown by the analysis of molecular variance. Thi s agrees with the expectation for an apomictic species such as L. dufo urii. The analysis of homogeneity of variance shows that substantial d ifferences in the amount of genetic variability present in the six pop ulations exist. These results have been used to understand the evoluti onary and demographic history of L. dufourii, which is a requisite in order to establish efficient conservation measures for this species.