The Canary Islands are genetic resources reservoirs where the major vegetation types and plant communities are endemism, included the Canary pine (Pinus canariensis Chr.Sm.Ex.Dc.). The conservation of the Pinus canariensis genetic resources is economically and scientifically interesting, because the genetic diversity could be analysed in islands of different size, age, and different ecological characteristics. In this study the genetic diversity of P. canariensis was assessed in 8 natural populations from 4 islands (Gran Canaria, Tenerife, La Palma and El Hierro) using six chloroplast microsatellite markers. Populations are characterized by similar genetic diversity parameters and the phenogram of populations showed a weak correlation with the insular distribution. The actual genetic diversity distribution of P. canariensis as revealed by cpSSR markers reflect an east-west pattern, that could be related to two different related factors: 1) An east-west trend in the age of the islands: P. canariensis populations from and emerging island would have their origin in the nearest neighbour population, following an east to west islands colonization pathway. 2). An east-west clinal climate variation. When intra-island variation is considered, some degree of isolation is observed among Northern and Southern populations in Tenerife and Gran Canaria Islands. Implications for conservation of genetic resources of the species are discussed.

Key words: Canary Islands, Genetic diversity, Microsatellites, PInus canariensis