Treatment of grapevines with prohexadione calcium as a growth regulator. The influence on production, winemaking and sensory characteristics of wines

Abstract

<p style="text-align: justify;"><strong>Aims</strong>: The overall objective of this study was to investigate the effect of the growth regulator Prohexadione Calcium (ProCa) on the production of Tempranillo vines in La Rioja, the vinification and the sensory profile of wines obtained from treated grapes.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Prohexadione calcium was applied to Tempranillo vines from Rioja Baja at preblooming in years 2004 and 2005. A number of rows were not treated and they were used as controls. Vinification was carried out at an experimental winery. Oenological parameters were determined. A sensory analysis was performed on the obtained wines. The results showed that crop yield was reduced in treated vines. As regards the fermentation process, slight differences were observed in the case of the treated Tempranillo grapes in comparison to the control. The sensory analysis revealed different organoleptic characteristics in the wines obtained from treated grapes in comparison to those produced from the untreated ones.</p><p style="text-align: justify;"><strong>Conclusion</strong>: The growth regulator Prohexadione calcium can be used as an alternative to bunch thinning. Improved sanitary conditions of grapes are observed. The treatment at preblooming produces a reduction in berry size and weight. An improvement in sensory characteristics and wine quality is observed, as a consequence of reduced production.</p><p style="text-align: justify;"><strong>Significance and impact of study</strong>: ProCa as a growth regulator may be an option for a quality vitiviniculture. No previous studies have been published on applications of ProCa in grapevines in either Europe or in cv. Tempranillo. Additionally, studies with other varieties have not demonstrated sensory improvements in wines obtained from treated vines.</p>