Genetic resources of the oldest trees of Pinus sylvestris L. from the last natural forest in Europe

The last fragments of primeval forests in the European lowlands have survived in the Białowieża Forest (BF). A characteristic feature of its forest stands is a complex and multi-age structure. From a genetic perspective, old trees represent a genetic pool that is a product of the selection forces acting over centuries. Therefore, it is extremely important to make a genetic inventory of such old trees and preserve their genetic resources for future generations. The aims of this study were: 1) genotyping the oldest trees of Pinus sylvestris in the Sitki Reserve of the Białowieża Forest in Poland; and 2) characterisation of the genetic structure of this old Scots pine tree stand. In total, 98 old trees aged above 100 years were analysed using eight nuclear microsatellite markers. The first study on the genotyping of the oldest Scots pine trees in the BF, indicated that each of the trees has a unique genotype, so it can be unambiguously identified by a genetic profile. Overall, 85% of trees showed an individual heterozygosity of 0.5 or higher. We demonstrated, that eight polymorphic microsatellite loci of the nuclear genome are sufficient to create an individual genetic profile of each tree. Our results will provide necessary background information for the conservation of native genetic resources of Pinus sylvestris.