GENETIC-VARIATION OF SILVER FIR (ABIES-AL BA MILL) IN BAVARIA

The genetic variation within and between 14 Abies alba stands was inve stigated on 9 polymorphic gene loci using isozyme analysis. The result s were compared to selected tree collectives (290 clones) from the nor thern and southern part of the provenance region 82708 (''Mountain Reg ion of Eastern Bavaria''). In the investigated area small scale geneti c differentiation was found. Geo-clinal variation in allele frequencie s was observed for the gene loci IDH-B and LAP-A. The genetic distance between the stands varied between 0.02 and 0.159. A cluster analysis based on the genetic distance differentiated the stands into 3 groups: 1. Stands of Abies alba from the northern provenance region 82708 (Fr ankonian Forest and Fichtel Mountains); 2. Stands from southeastern Ba varia (Bavarian Forest, eastern Bavarian Alps); 3. Southwestern Bavari a (Ottobeuren). The genetic variation (population differentiation and diversity) in the Ottobeuren stand is significantly higher than in the other stands. In contrast the stands in group 1 are characterized by less differentiation and diversity. The 2 (in 1980) selected tree coll ectives (north and south collective) for seed orchards differ signific antly in their genetic structure. The selected sample trees are, howev er, genetically similar to the corresponding stands in the respective region. The presented results contribute further information on the ge netic variation of Abies alba in its native range and can be used in p rovenance identification and in delineating provenance regions.