Quantitative traits and random amplified polymorphic DNA variations were investigated on the whole natural range of Norway spruce (Picea abies (L.) Karst.). Results showed that the species can be separated into two main groups (northern and central Europe) using both types of characters. Such spatial and geographical fragmentation of species natural range rarely occurs in conifers and is consistent with prolonged geographical isolation within two refugial zones located in distinct environmental conditions (Moscow area and east of central European mountains). Within each of these two infraspecific groups, we revealed an apparent uncoupling between quantitative traits (related to growth, phenology, and wood quality) and DNA. However, the combination of both molecular and quantitative traits information provided new insights about geographical patterns of variation: a dominant latitudinal gradient was found in the Baltico-Nordic domain contrasting markedly with the main east–west migration expected from pollen data, while in central Europe, a noticeable longitudinal gradient was congruent with east–west migration. The concordance and discrepancies between quantitative traits and DNA are discussed in terms of historical events in P. abies.

A mosaic minisatellite region has been identified in the mitochondrial genome of Norway spruce (Picea abies). The array was composed of three tandem repeats PaTR1 (32 bp), PaTR2a (26 bp) and PaTR2b (26 bp). PaTR2a and PaTR2b differed by one base substitution. The analysis of 92 trees covering the whole natural distribution area of the species allowed detection of 11 length variants ranging from 131 bp to 447 bp. This high intra-specific polymorphism relies on variation in the number of the tandem repeats. Population genetic parameters estimated among 14 populations suggested high population differentiation (Gst=0.749). The phylogenetic analysis of the 11 sequenced length variants has been performed using a parsimony approach. The topology of the tree showed a good association of groups with geographical origin and a low level of size homoplasy. The phylogenetic reconstruction also suggests that this minisatellite locus has mainly evolved by an increase in the repeat copy number.

RAPD analysis was used (1) to assess the diversity of indigenous Picea abies within the French massifs (Alps, Jura and Vosges) in comparison with the Hercyno-Carpathian and Alpine domains (central Europe); and (2) to examine the molecular relationships among provenances of these massifs and domains. One hundred and thirty-seven polymorphic RAPD fragments were screened. Results showed that the phenotypic diversity estimates within the dierent massifs and domains analysed were similarly high. Factorial correspondence and cluster analyses revealed geographical structuring along a latitudinal gradient among the French massifs and a longitudinal gradient from eastern Europe to France. Provenances from the southern French Alps appeared to be genetically distinct from the others. Hypothetical postglacial pathways into the French massifs are proposed and the putative implications of an additional refuge located in the Tuscan Apennines is discussed.

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