scholarly journals Early Leaf Removal Increases Berry and Wine Phenolics in Cabernet Sauvignon Grown in Eastern Serbia

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 238
Author(s):  
Dejan Stefanovic ◽  
Nina Nikolic ◽  
Ljiljana Kostic ◽  
Slavica Todic ◽  
Miroslav Nikolic

Cluster zone leaf removal is a well-established viticulture practice for improving cluster microclimate and wine quality in cooler climates, while its efficacy in warmer conditions is less is known. Here we compared the effect of early (ELR, after fruit set; diameter of berries 3–5 mm) and late (LLR, beginning of veraison) leaf removal on berry composition and wine phenolic profile of grapevine (Vitis vinifera L.) variety Cabernet Sauvignon grown in a temperate, warmer region of Eastern Serbia. Compared to the control (no leaf removal), both leaf removal treatments increased the sugar content in fresh juice and alcohol concentration in wine. Over three consecutive years (2011–2013) markedly different in temperature and rainfall, ELR was clearly most effective in decreasing weights of cluster and of one berry, and in increasing of skin share in a berry. The content of total phenols, tartaric acid esters, anthocyanins, and flavanols in berry skin and wine was the highest in ELR treatment. ELR prominently modified the phenolic profile: Increasing flavanols, myricetin and quercetine in skin and wine, and anthocyanins, peonidin-3-glucoside in skin and delphinidin-3-glucoside in wine. This work demonstrated that early leaf removal positively influenced the chemical composition of berries and wine of Cabernet Sauvignon and might be recommended for practice in the temperate warm conditions.

Agriculture ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 176
Author(s):  
Gastón Gutiérrez-Gamboa ◽  
Irina Díaz-Galvéz ◽  
Nicolás Verdugo-Vásquez ◽  
Yerko Moreno-Simunovic

A trial was conducted during the 2005–2006 season in order to determine the effects of different leaf-to-fruit ratios on yield components and fruit composition in four Vitis vinifera L. cultivars. The treatments consisted of selecting shoots of four lengths (>1.3 m, 1.3–0.8 m, 0.8–0.4 m, and <0.4 m) with two crop levels (1–2 clusters/shoot), which allowed defining eight ratios. Berry composition and yield components were measured. The treatments affected the accumulation of soluble solids in “Sauvignon blanc”, “Cabernet Sauvignon”, and “Syrah”, delaying it as the ratio decreased. All yield components were affected in “Sauvignon blanc”, while bunch weight and the number of berries per bunch were altered without a clear trend. None of the yield components were affected in “Cabernet Sauvignon”, while the lowest ratio presented the lowest number of berries per bunch in “Syrah”. Total polyphenol index (TPI) was affected in “Carmenère” without a clear trend. A highly significant correlation was found between shoot length and leaf area in all studied cultivars. As the ratio increased, the shoot lignification increased in “Sauvignon blanc”. However, studies must be conducted during more seasons to establish better conclusions about the effects of leaf-to-fruit ratios on yield and fruit composition.


2017 ◽  
Vol 218 ◽  
pp. 147-155 ◽  
Author(s):  
Chiara Pastore ◽  
Gianluca Allegro ◽  
Gabriele Valentini ◽  
Enrico Muzzi ◽  
Ilaria Filippetti

HortScience ◽  
2019 ◽  
Vol 54 (7) ◽  
pp. 1181-1189 ◽  
Author(s):  
Cain C. Hickey ◽  
Tony K. Wolf

Selective leaf removal in the proximity of grape clusters is a useful practice to manage fruit diseases and otherwise improve fruit composition. The current recommendation in the eastern United States is to create a fruit zone with one to two leaf layers and to focus removal on the “morning sun” side of the canopy. We evaluated a more intense and an earlier application of fruit-zone leaf thinning relative to current recommendations to determine whether additional benefits could be obtained without a penalty of impaired berry pigmentation or other ill effects of abundant grape exposure. Fruit secondary metabolites and berry temperature were monitored in two different field experiments conducted with ‘Cabernet Sauvignon’ in the northern Shenandoah Valley American Viticultural Area (AVA) of Virginia. One experiment evaluated the effects of no leaf removal, prebloom removal of four basal leaves per shoot, and prebloom removal of eight basal leaves per shoot. The other experiment evaluated the effects of no leaf removal and postfruit set removal of six basal leaves per shoot. On average, exposed grapes heated to ≥30 °C for a 126% longer period (53 hours) than shaded grapes in the postveraison period (from color development through harvest). However, postveraison grape temperatures did not remain above provisional, critical temperature thresholds of either 30 or 35 °C for as long as they did in studies conducted in sunnier, more arid climates. There were minimal differences in berry temperature between east- and west-exposed grapes in the northeast/southwest-oriented rows of the experimental vineyard. Regardless of implementation stage, leaf removal consistently increased total grape phenolics measured spectrophotometrically, and either increased or had no impact on anthocyanins relative to no leaf removal. Grape phenolics and anthocyanins were unaffected by canopy side. Berry total phenolics were increased and anthocyanins were at least maintained in fruit zones void of leaf layers—a canopy attribute that reduces bunch rot in humid regions.


2003 ◽  
Vol 30 (6) ◽  
pp. 711 ◽  
Author(s):  
Paul R. Petrie ◽  
Michael C. T. Trought ◽  
G. Stanley Howell ◽  
Graeme D. Buchan

Canopy topping and leaf removal are management practices commonly used in New Zealand vineyards to increase light and pesticide penetration to the fruit zone, thus, reducing disease incidence. Previous research has suggested that an increase in photosynthesis occurs when leaves are removed, and this may compensate for the reduced leaf area. However, it is difficult to extrapolate single-leaf photosynthesis measurements to a whole-plant scale. Therefore the extent of the compensation is unknown. To evaluate the impact of leaf removal and canopy height on whole-vine photosynthesis, treatments were imposed during the lag phase of berry growth. Leaves were removed from the lower quarter of the canopy, or vines were topped to three quarters of the height of control plants, in a two-by-two-factorial design. Both topping and leaf removal caused a decrease in whole-vine photosynthesis immediately after the treatments were imposed. Leaf removal, but not topping height, reduced photosynthesis on a per unit leaf area basis. This suggests that the lower portion of the canopy contributes more than the upper portion of the canopy to whole-vine photosynthesis. When measurements were made again approximately two months later, tall vines without leaf removal had a higher photosynthesis rate than the other treatments. Fruit yield, sugar content, vine carbohydrate reserves and pruning weights followed trends similar to those observed for photosynthesis, suggesting that although some photosynthetic compensation occurred, the defoliation treatments had a negative effect on vine growth.


Sign in / Sign up

Export Citation Format

Share Document