Search

Background and Aims Climate change can alter the synchronous accumulation of sugar and other main berry compounds during ripening. The aim of this study was to determine whether post-veraison trimming could delay sugar accumulation and influence the production of anthocyanins and seed tannins in Sangiovese grapes. Methods and Results Shoots were trimmed in 2009, 2010 and 2011 when the berry total soluble solids ( TSS) reached 15-17° Brix, leaving eight nodes on each main shoot. The accumulation of TSS, anthocyanins and seed tannins was measured during ripening, and yield parameters were recorded at harvest. Grapes from trimmed vines contained a lower TSS in 2009 and 2010, but there was no impact on the concentration of anthocyanins and seed tannins. In 2011, leaf area limitation was insufficient to reduce TSS accumulation, because yield constraints were observed and the leaf area/yield ratio was within the optimal range. Conclusions The lower rate of TSS accumulation in berries had no impact on the concentration of anthocyanins and seed tannins, suggesting that this approach could produce grapes with a lower TSS at harvest or delay harvest. In low-vigour vines suffering from water deficit, the post-veraison trimming repeated over the years could reduce yield, which may be responsible for the lack of TSS reduction compared with that of control vines. Significance of the Study Our study provides insight into the relationship between TSS accumulation and the production of anthocyanins and seed tannins in the berry in response to post-veraison leaf area reduction. [ABSTRACT FROM AUTHOR]