tailieunhanh - Báo cáo lâm nghiệp: "Genetic variability and divergence among Italian populations of common ash (Fraxinus excelsior L.)"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Genetic variability and divergence among Italian populations of common ash (Fraxinus excelsior L.). | Ann. For. Sci. 64 2007 159-168 INRA EDP Sciences 2007 DOI forest 2006100 159 Original article Genetic variability and divergence among Italian populations of common ash Fraxinus excelsior L. Diana FERRAZZINI Ignazio MONTELEONE Piero BELLETTI University of Turin DIVAPRA Plant Genetics and Breeding via Leonardo da Vinci 44 10095 Grugliasco Italy Received 4 April 2006 accepted 6 July 2006 Abstract - The level of genetic variation throughout the Italian range of common ash Fraxinus excelsior L. was estimated using six microsatellite markers. High levels of allelic diversity was detected. The levels of expected heterozygosity for each of the populations ranged from to with an average of and indicated that populations have a high level of genetic variation. A general and significant homozygote excess was found at most loci in all populations with an overall mean FIS of . Possible explanations for such situations are discussed. Only of the total diversity was attributable to differentiation among populations. Although divergence among pedo-climatic regions explained only a small part of the variance it was possible to observe some partial clustering of populations belonging to the same regions. The contribution of the results in relation to the definition of the most appropriate strategies to collect forest reproductive material is discussed. genetic variation microsatellite population differentiation seed zone designation Fraxinus excelsior Résumé - Variabilité génétique et differenciation entre populations italiennes de frêne commun Fraxinus excelsior L. . Le niveau de variation génétique dans l aire de distribution naturelle du frêne commun Fraxinus excelsior L. en Italie a été estimé à l aide de six marqueurs microsatellite. Des niveaux élevés de diversité allélique ont été détectés. L hétérozygotie théorique varie de 0 726 à 0 871 avec une moyenne de 0 798 ce qui indique que les populations ont un niveau élevé de variation .