Genetic Diversity of <i>Juniperus communis</i> L. in Eurasia and Alaska, Inferred from Nuclear Microsatellites Markers

Abstract

The structure of genetic variation of the common juniper (Juniperus communis L.), a widespread wind-pollinated golarctic shrub of Cupressaceae was surveyed. We used 7 microsatellite markers including three new to genotype samples from 23 Eurasian populations and one from North America (Alaska). The geographical patterns are interpreted jointly with our previously available chloroplast DNA data. High genetic diversity was revealed with highest values in the same northern populations (Sweden, Estonia, Mezen, Polar Urals, Yamal, Kolyma, as well as in the Alps) as previously identified at cpDNA analysis. Nuclear markers exhibited a lower level interpopulation differentiation (FST = 9.8%) than chloroplast markers (FST = 76%). Bayesian cluster analysis showed that the optimal number of genetic groups (K) was two. All the 24 populations of J. communis were divided into the East group (north-east and Far East of Russia, Alaska and Himalayan) and the West group (Europe, Ural and Siberia). In the Alpine and Mountain Shoria populations, genotypes from different genetic groups are combined.