Needle volatiles as chemophenetic markers in differentiation of natural populations of Abies alba, A. x borisii-regis, and A. cephalonica.

Seventeen native fir populations from the presumed zones of natural hybridization in the Balkan Peninsula were analyzed using headspace needle volatiles and GC-MS/FID analyses. The multivariate statistical analyses revealed clear differentiation between populations of Abies alba and A. cephalonica, suggesting that Silver and Greek Fir are characterized by distinct volatile profiles. Three populations from northern and central Greece identified as A. x borisii-regis shared the volatile profiles with both of the supposed parent species, whereby profile frequencies changed clinally along the latitudinal gradient connecting the ranges of parent species. Therefore, observed geographical distribution of volatile entities support the hypothesis that studied A. x borisii-regis populations are of secondary origin, formed by hybridization between A. alba and A. cephalonica. All three populations should be included in conservation projects, as the genetic constitution of these polymorphic fir populations may contain useful genetic variation necessary for survival regarding the future environmental challenges in this area.