DETERMINISM OF THE TERPENOL CONTENT IN A 'MUSCAT OTTONEL' SELF-PROGENY

Linalool, geraniol, nerol, citronellol and –terpineol are isoprenoid molecules responsible for specific aromas found in grapes and wines. The concentrations of these compounds were measured in the skins of mature berries during two successive years in a population derived from a ‘Muscat Ottonel’ selfing grown in the greenhouse and segregations of these traits were observed. A genetic map based on microsatellite markers was constructed and several QTLs were detected. A major QTL was identified on linkage group 5, closely linked to the VVIi52 marker. We hypothesized that the synthesis of terpenols at a high level was not possible in plants lacking a favourable allele at this locus. A second QTL, on linkage group 10, determined the balance between linalool and geraniol, the two main analysed compounds.