LAUSR

BACKGROUND 'Xynisteri' is the reference Cypriot white cultivar that, despite its significant societal and economic impact, is poorly characterized regarding its qualitative properties, while scarce information exists regarding its aroma profile. In the current study, the effect of leaf removal during fruit set (BBCH 71) on 6-year cordon-trained, spur-pruned grapevines was assessed and an array of physiological, biochemical and qualitative indices were monitored during successive developmental stages (BBCH 75, 85, 87, 89). Grapes were additionally monitored for the volatile organic compounds (VOCs) profile during the advanced on-vine developmental stages (BBCH 85-89) with the employment of GC-MS, FT-NIR and E-nose techniques. RESULTS Grape berries from the vines subjected to leaf removal were characterized by higher SSC, TA, tartaric acid and ammonium nitrogen contents, while this was not the case for assimilable amino nitrogen (primary amino nitrogen). A total of 75 compounds were identified and quantified, including aliphatic alcohols, benzenic compounds, phenols, vanillins, monoterpenes and C13 -norisoprenoids. Leaf removal led to enhanced amounts of glycosylated aroma compounds, mainly monoterpenes and C13 -norisoprenoids. Chemometric analysis, employed through FT-NIR and E-nose, showed that the aromatic patterns detected were well associated to the grape ripening trend and differences between LR-treated and control grapes were detectable during fully ripe stage. CONCLUSION Leaf removal at fruit set resulted in an overall induction of secondary metabolism, with special reference to glycosylated aroma compounds, namely monoterpenes and C13 -norisoprenoids. This article is protected by copyright. All rights reserved.