Geographic variation in Juniperus drupacea: DNA sequencing and volatile leaf oils: Further evidence of putative Pleistocene genetic isolation between Europe and Asia
Recently, Sobierajska et al. (2016), using nSSR and morphology, showed that Juniperus drupacea exhibited differentiation between Greece and Turkey/ Lebanon, suggestive of Pleistocene genetic isolation. Here, we report that leaf terpenoids and DNA sequence data support their hypothesis by confirming differentiation between Greece and Turkey/ Lebanon/ Israel. The leaf oils of the Turkey/ Lebanon plants contained one unique terpene (trans-verbenol, 0.1-1.4%) that was absent in the Greece plants. The Greece oil contained three terpenes not found in the Lebanon/ Turkey plants: (ar)-curcumene (2.2%), β-alaskene (0.3%) and α-alaskene (0.4%). Four other terpenes were in higher concentration in the Greece oils: camphene (0.4%), δ-3-carene (10.9%), p-mentha-1,5-dien-8-ol, isomer (0.3%) and 4-terpineol (0.3%). Three terpenes were higher in Turkey and Lebanon oils: α-pinene (10.5 - 32.9%), hexadecanoic acid (0.4 - 1.4%) and trans-totarol (0.3 - 1.2%). Only one SNP was found (in nrDNA) that separated Greece from Turkey-Lebanon-Israel. No informative SNPs were found in petN-psbM, trnS-trnG, trnD-trnT or trnL-trnF cp regions
