Genetic differentiation in Pinus brutia Ten. using molecular markers and quantitative traits: the role of altitude

Turkish red pine (Pinus brutia Ten.) is widespread in the eastern Mediterranean Basin. In the late 1970s, four common gardens were established along steep altitudinal transects extending from the coast to about 1,200 m in the Taurus Mountains (Antalya, Turkey). The aim was to study the role of altitude in shaping Turkish red pine genetic diversity and population structure as well as to evaluate the existence of local adaptation along altitudinal gradients in this species. Genetic diversity and population structure were evaluated in replicated altitudinal gradients using chloroplast microsatellite (cpSSR) markers. Genetic differentiation for neutral markers was compared with quantitative differentiation for growth traits for the same populations evaluated at different altitudes. Genetic differentiation among altitudinal groups was higher than among transects. A high portion of the genetic variance corresponded to families within populations (up to 10.75%). Overall quantitative genetic differentiation (Q (ST)) was higher than molecular differentiation in most test sites for all the traits and ages considered. Turkish red pine shows signatures of local adaptation to environmental gradients related to altitude. For forestry practices, such as selection of seed sources, both altitude and the family level of variation need to be considered.