title: Chemical and genetic differentiation of Corsican subspecies of Teucrium flavum L.
abstract: Corsica Island exhibited the particularity to display Teucrium flavum subsp. glaucum and subsp. flavum on the same territory with the same bioclimatic conditions. For the first time, volatile components extracted from aerial parts and genetic diversity of both Corsican T. flavum L. subspecies have been investigated through (i) the characterization of the chemical composition of essential oils and (ii) the study of three polymorphic genetic markers. Chemical analysis were performed using combination of capillary GC/RI, GC-MS after fractionation on column chromatography and the definition of the genetic structure were carried out using two chlororoplast markers (RPL32-TRNL and TRNL-F) and ribosomal nuclear markers (ITS region). According to statistical analysis, both subspecies were clearly distinguished by the chemical and genetic studies. Chemical compositions of oils from both subspecies were qualitatively similar but they differed by the normalized% abundances of their major components; oils from subsp. flavum were dominated by large amounts of hydrocarbon monoterpenes while oils obtained from subsp. glaucum were characterized by higher amounts of oxygenated compounds. The genetic analysis divided T. flavum L. populations in two groups, the first displayed subsp. glaucum populations and the latter group exhibited subsp. flavum populations. The presence of two groups is weakly consistent with chemical differentiation. These data suggest that the differences in the volatile composition of the two T. flavum subspecies depends more on the genetic background and less on environmental factors.
authors.affiliation: Université de Corse, UMR CNRS 6134, Laboratoire Chimie des Produits Naturels, Campus Grimaldi, BP 52, 20250 Corte, France.
authors.forename: Nassim
authors.initials: N
authors.lastname: Djabou
authors.forename: Marie-José
authors.initials: MJ
authors.lastname: Battesti
authors.forename: Hocine
authors.initials: H
authors.lastname: Allali
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Desjobert
authors.forename: Laurent
authors.initials: L
authors.lastname: Varesi
authors.forename: Jean
authors.initials: J
authors.lastname: Costa
authors.forename: Alain
authors.initials: A
authors.lastname: Muselli
mesh_terms: D005591:Chemical Fractionation / Q000379:methods; D002736:Chloroplasts / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D005602:France; D008401:Gas Chromatography-Mass Spectrometry; D005819:Genetic Markers; D039821:Monoterpenes / Q000032:analysis / Q000737:chemistry; D009822:Oils, Volatile / Q000032:analysis / Q000737:chemistry*; D011110:Polymorphism, Genetic; D025341:Principal Component Analysis; D017422:Sequence Analysis, DNA; D012717:Sesquiterpenes / Q000032:analysis / Q000737:chemistry; D013045:Species Specificity; D031367:Teucrium / Q000737:chemistry* / Q000235:genetics; D055549:Volatile Organic Compounds / Q000737:chemistry
chemical_list: D018742:DNA, Chloroplast; D021903:DNA, Ribosomal Spacer; D005819:Genetic Markers; D039821:Monoterpenes; D009822:Oils, Volatile; D012717:Sesquiterpenes; D055549:Volatile Organic Compounds