European black pine (Pinus nigra Arnold) is widespread from North Africa through southern Europe, the Balkans and eastwards to Turkey and the northeastern shores of the Black Sea. Throughout this wide range, fragmentation of populations has undoubtedly led to differentiation through isolation and through differential selection pressure. Our population analyses of the western range of this species using foliar terpenes had indicated the existence of three main groups: ssp. nigra from Bulgaria, Greece, Italy and Austria, ssp. laricio from Corsica and ssp. salzmannii from southern France and northern Spain. Chloroplast microsatellite data confirm genetic differentiation of Corsican, Austrian/Italian and French populations with Corsican populations the most distinct. Populations from southern France are likely to have been seriously modified by replanting, after exploitation, with preferred provenances from Corsica and Austria. The degree to which native stands of this species in the French Cevennes are genetically polluted by imported provenances is unknown. We have identified stands of salzmannii that appear to be more or less pure. These are growing on very harsh sites, suggesting lack of competition from the exotic provenances. We have also detected the presence of nigra and laricio genotypes on adjacent, more fertile sites.

Key words: Pinaceae, Pinus nigra subspecies salzmannii, population genetic structure