Effects of timing of leaf removal on yield, berry maturity, wine composition and sensory properties of cv. Grenache grown under non irrigated conditions

Abstract

<p style="text-align: justify;"><strong>Aims</strong>: The objective of this study was to investigate the effects of timing of leaf removal on yield components, berry sensory characteristics, composition and sensory properties of Vitis vinifera L. Grenache wines under non-irrigated conditions.</p><p style="text-align: justify;"><strong>Methods and results</strong>: The effects of timing of defoliation (fruit set and veraison) on yield components, berry maturity, wine composition and sensory properties of head trained, non irrigated, Grenache vines grown in Rioja appellation were studied. Leaf removal did not significantly modify total leaf area per vine as well as yield components. Grenache berries from early defoliated vines achieved the highest skin and technological maturity. Wine parameters, such as alcohol content, pH, titratable acidity, tartaric acid and total polyphenol index were unaffected by defoliation. Conversely, early leaf removal carried out at fruit set, significantly reduced the malic acid content of the wine and enhanced its colour intensity. Aroma complexity, mouthfeel, tannin quality and persistence were found to be significantly higher in the wine corresponding to the early leaf removal treatment. This was also the most preferred wine in terms of overall value.</p><p style="text-align: justify;"><strong>Conclusion</strong>: This article shows that timing of leaf removal had a marked effect on berry maturity, wine composition and sensory properties of Grenache wines made from grapes grown under dry-farmed conditions.</p><p style="text-align: justify;"><strong>Significance and impact of study</strong>: The results suggest that the timing of defoliation induces significant changes in Grenache wine composition and its sensory attributes. Late leaf removal was much less effective than early leaf removal in affecting final wine composition and quality. Grenache wine from the early defoliation treatment was rated the most preferred as of global value.</p>

Yield of Müller-Thurgau and Riesling grapevines is altered by meteorological conditions in the current and previous growing seasons

“…Moreover, canopy management practices have been shown to be efficient tools to manipulate the degree of fruit set, cluster compactness, and yield. Consequently, if past and present environmental conditions lead to the expectation of an excessively high yield potential (i. e., over-cropping) in the present season, yieldreducing viticultural practices such as early clusterzone leaf removal (Molitor et al, 2011;Poni et al, 2006 ;Tardaguila et al, 2008) or late first shoot topping (Hügelschäffer et al, 1994 ;Molitor et al, 2015) might be employed.…”

Effects of different level of leaf removal applications on mineral substance of raisins in organic Sultani Çekirdeksiz grape growing

“…Basal leaf removal is one of the most common practices in canopy management [6,8,14,22,23]. It is frequently done during the ripening season if the canopy has a very high density, in an attempt to improve the colour intensity and aroma and to decrease the disease impact of pests [7,22].…”

Does Full Exposure of Clusters Have Any Negative Effects on Tempranillo (Vitis vinifera L.) Grape Quality in La Rioja, Spain? The Use of Severe Cluster-zone Leaf Removal after Berry Set

“…It is worth mentioning that most previous LR experiments were conducted by only removing the basal leaves, with the lateral buds or shoots left behind. In this way the remaining leaves and the newly grown lateral shoots may have a higher assimilation rate, which could compensate for the reduction in leaf area (LA) caused by LR (Poni et al, 2006;Tardáguila et al, 2008;Diago et al, 2012). Moreover, cluster shading could reappear due to the lateral shoots, which means that the LR operation has to be repeated when necessary (Smart & Robinson, 1991).…”