ALLOZYME VARIATION IN ITALIAN POPULATIONS OF PICEA-ABIES (L) KARST

Genetic diversity and genetic differentiation of nine Italian populations of Norway spruce (Picea abies (L.) KARST.) were studied analyzing allozyme variation at 21 loci. On average, the expected heterozygosity was 0.165, 45.50% of loci were polymorphic, the number of alleles per locus was 1.831 and the effective number of alleles per locus was 1.198. Only 4.2% of the total genetic variation was due to interpopulational differentiation. The mean value of NEI'S genetic distance (0.019) confirmed that the variation among populations is low. The characteristics of the relic population of Campolino (the only natural stand located in Italy outside the Alps), such as a quite high gene diversity, the presence of some unique alleles and a peculiar genetic structure at the locus GOT-B, may provide some support to the hypothesis of a post-glacial recolonization of the Italian slope of the Alps in West-East direction, starting from refungial populations in Central Italy.