Abstract
The unambiguous identification of closely related species is useful for many practical purposes in forest tree species. For example, international laws require timber identification and the control of the origin of forest reproductive material. In this paper, we present a mitochondrial DNA marker which can be used to differentiate among groups of fir species (Abies spp.). Eight Mediterranean and one North American fir species (used as reference) were analysed at the fourth intron of the NAD subunit 5 gene. A total of six different haplotypes was identified, one in the American Abies concolor, the other five in Mediterranean species. Two different haplotypes were found each in the widespread A. alba and in A. cephalonica, one haplotype being shared among the two species. A single species specific haplotype was found in the near-eastern A. cilicica. The two southwestern species A. pinsapo and A. numidica shared one haplotype. The fifth haplotype was shared by all remaining eastern Mediterranean firs, A. cephalonica, A. bornmuelleriana, A. equi-troiani, and A. nordmanniana. Differences in haplotype sequences were mainly due to large insertions/deletions. Agarose gel electrophoresis thus provides a fast, cheap and reliable diagnosis method for species or species group identification.