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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. [Copyright &y& Elsevier]

Abstract: Fifty Corsican “chestnut grove” honeys were certified by melissopalynological analysis. Castanea sativa was strongly overrepresented and was accompanied mainly by Rubus sp., Quercus ilex, Anthyllis hermanniae, Myrtus communis, Genista sp., Erica arborea, Cistus creticus, and Fraxinus ornus. Headspace solid-phase microextraction was performed to investigate the volatile composition of Corsican chestnut catkins and chestnut grove honeys. The main compounds of the chestnut catkins were acetophenone (21.5%), methyl salicylate (13.4%), nonanal (10.9%), and linalool (7.5%), whereas the major constituents of the honeys were 2-aminoacetophenone (11.4%), benzaldehyde (10.8%), acetophenone (7.0%), nonanoic acid (5.9%), octanoic acid (5.0%), and 3-furaldehyde (4.9%). By entering the aromatic intensity, the relative frequency of C. sativa, Rubus sp., and A. hermanniae pollens, and the physicochemical parameters as discriminate variables, principal component analysis (PCA) and cluster analysis (CA) showed that the distribution of Corsican “chestnut grove” honeys correlates with climatic events and/or honeybee foraging behaviours. [Copyright &y& Elsevier]