Genetic variation of Polish Scots pine (Pinus sylvestris L.) populations assessed with DNA polymorphism markers - Justyna A. Nowakowska

Justyna A. Nowakowska. Instytut Badawczy Leśnictwa, Sękocin Stary, 2007, ISBN 978-83-878647-70-4, 118 pp. In Polish, with abstract, summary, tables and figures in English. 32 EUR

Abstract. The investigations of the genetic structure were performed on 42 Scots pine populations located in six Natural-Forest Regions in Poland using nuclear microsatellite (SSR) and mitochondrial (STS) markers loci.

The nuclear microsatellite markers revealed higher polymorphism level (PIC = 80.0 %) than the mitochondrial nad1 locus (PIC = 40.2 %). Pine trees from the investigated stands were characterised by a low level of inter-population differences where the microsatellite (FST = 0.033) and mitochondrial (FST = 0.118) markers were concerned. The highest genetic diversity was present in the Baltic (FST = 0.036 based on SSR), Śląska and Wielkopolsko-Pomorska Natural-Forest Regions (HS = 0.323 and HS = 0.207 respectively). Conversely, the lowest genetic diversity for SSR markers was found in the Śląska Region (FST = 0.013). Based on STS markers, the lowest genetic diversity was found in the Mazursko-Podlaska Natural-Forest Region (HS = 0.006).

The UPGMA analysis based on both kinds of markers revealed two main clusters of populations separated by little genetic distances with a very weak probability of clustering. The geographical localization of the populations from each cluster based on SSR and STS data was scattered across the country and no spatial correlation between the gene diversity and the geographical locations of stands was found. The Mazursko-Podlaska Natural-Forest Region turn out to be the most genetically homogenous region with almost one type of the genotype and haplotype from the first cluster of the genetic similarity dendrograms.

The scattered distribution of P. sylvestris genotypes across Poland revealed by SSR and STS markers seems to reflect the historical events such as colonization of Poland by this species from different gene pools and significant human management practiced in Poland in the past. Basing on the data for other forest tree species, the migration routes of the Polish Scots pine populations originated from the three main glacial refugia were suggested, i.e. the Balkan and Apennine Peninsulas, and the Central Russia.

Key words: genetic differentiation level, mitochondrial (STS) and nuclear (SSR) DNA markers, genetic similarities among stands, intra- and inter population genetic variation, Pinus sylvestris L.