Microsatellite loci polymorphism of chloroplast DNA of scots pine (Pinus sylvestris L.) in Asia and eastern Europe

The variability of four microsatellite loci of chloroplast DNA was studied in 38 populations of Pinus sylvestris in the European part of Russia, in Siberia, Kazakhstan, Transbaikalia and Mongolia. High variability was observed in all regions. In total, 152 haplotypes were identified. The level of population differentiation R _ST was 2.1%. The differentiation of three geographical groups of populations (European, Siberian-Kazakhstan and Transbaikalian-Mongolian) was insignificant (R _CT = 0.004). At the same time, some rare haplotypes were found to be specific for a certain geographical region. Distribution of the rare haplotypes, which differentiated European populations from Asian populations and Mongolian and Transbaikalian populations from the Siberian, showed the independence of the history of these regions. This corresponds more to the hypothesis that the modern area of Pinus sylvestris originated via settlement from many origins than to the hypothesized single center of the post-glacial recolonization. The distribution of the pairwise differences between the individual specimens corresponded to the model of sudden population growth. The assessments of the age of this event for Pinus sylvestris (4.5–4.7 million years), which were obtained on the basis of this model, significantly exceeded the age of the Quaternary. Therefore, the revealed population growth is hardly due to the changes in flora related with the glaciation, but rather mirrors the moment of the species formation.