Effect of viticultural practices on yield and volatile composition of ‘Cabernet Sauvignon’ grapes

Abstract

‘Cabernet Sauvignon’ is a vigorous grapevine that develops herbaceous aromas in grapes. Canopy management practices can impact grapevine physiology, and as consequence the photosynthesis, fruit yield, and grape composition, and improve the quality of the fruit. Leaf removals and apical leaf removals on grapevines have been shown to reduce herbaceous aromas. However, little is known, about the effect of the use of girdling on the concentration of volatile compounds in grapes. Thus, the objective of this study was to evaluate the effect of basal leaf removal (BLR), girdling, and girdling plus cutting the apical regions of the canopy (girdling + CAC), on the concentration of volatile compounds of ‘Cabernet Sauvignon’ grapes. Fruit yield, chemical composition, and volatile compounds were analysed in all treatments. Girdling + CAC showed a reduction in grape yield, and total acidity, however, increases in total soluble solids, and fruity aromas were observed in comparison to BLR and the control (no-canopy treatment). Controls showed the highest concentration of volatile compounds related to herbaceous and unripe fruit characteristics aromas. On the other hand, BLR showed increases in volatile compounds in the grapes related to floral character. These results suggest that grapevine canopy management modifies the chemical composition of ‘Cabernet Sauvignon’ grapes, and girdling techniques and increase the fruity aromas.