[Genetic polymorphism of Siberian spruce (Picea obovata Ledeb) in middle Siberia]

Based on the analysis of 22 loci controlling allozyme variation of MDH, SKDH, 6-PGD, IDH, PEPCA, GOT, FDH, LAP, PGI, PGM, SOD, and GDH, the data on within- and among-population variation for nine cenopopulations of Siberian spruce (Picea obovata Ledeb.) located along the Yenisei meridian, from 65 degrees 50' NL to 52degrees 14' NL, were obtained. It was demonstrated that 86.36% of the loci, tested in the species analyzed, were polymorphic. The mean number of alleles per locus was 2.91, and the observed and expected heterozygosity constituted 0.161 and 0.168, respectively. More than 97% of total variation occurred within the populations, while the proportion of the among-population variation constituted only 2.3% (Fst =0.0230). Genetic distance (DN) between the populations examined varied from 0.0019 to 0.0115, averaging at 0.0051. It was shown that in the part of the Siberian spruce range examined there was no close association between the level of the genetic differentiation of the populations and the geographic distance between them. It seems likely, that this finding can be associated with the fact that Siberian spruce, growing on this territory, is the intrazonal species, i.e., it is not attached to a certain forest zone, and its distribution is mostly determined by local ecological conditions.