# Early Basal Leaf Removal at Different Sides of the Canopy Improves the Quality of Aglianico Wine
## 3 Results and Discussion
### Phenolic Composition  
The phenolic composition of the wines, along with their antioxidant activity and color indices, are reported in Table 2. Season exerted a significant effect on all three parameters. As expected, the wines produced in 2017 had the highest contents of phenolic compounds and, consequently, had the highest levels of antioxidant activity and color intensity (\(p\leq 0.001\)). This can be explained by the major phenolic maturity of the grapes [26]. In fact, 2017 had the warmest climate and lowest rainfall from bud break to harvest when compared to 2016 and 2018, which induced the best ripening grade of the grapes [26] and, consequently, higher alcohol content, resulting in a major extraction of phenols. When comparing the wines from 2016 and 2018, the latter were characterized by a greater content of anthocyanins, antioxidant activity and color intensity (\(p\leq 0.001\)). Early defoliation had a significant impact on the phenolic characteristics, antioxidant activity and color intensity of the wines. In comparison to the control samples, all wines from defoliated vines were richer in flavonoids (+35-40%), anthocyanins (+15-18%), proanthocyanindins (+10-15%), total polyphenols (+10%), antioxidant activity (+8-16%) and color intensity (about +10%). A significant increase in flavonoids, FRV, total polyphenols and antioxidant activity was observed in the wines produced from vines where the leaves were removed from the south side of the canopy, in accordance with the results of other studies conducted on Cabernet-Sauvignon and Probus [35]. As for the FRV/P ratio, which is an index of the degree of tannin condensation, it was found to be lower in the wines produced from defoliated plants, especially those defoliated on the north side (0.87-0.94 versus 1.01 in control). This implies a decrease in tannin reactivity and a predisposition to tannin and color stabilization [36]. Defoliation exerted no influence on tonality. This finding could be explained by the fact that the wines were young, as they were analyzed at an age of about 7 months. Interactions (S*LR) were observed for all phenolic parameters, antioxidant activity and color intensity, as shown in Figure 2. \begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline
**Source of Variation** & **F** & **A** & **FRV** & **P** & **TP** & **AA** & & & \\
**(mg/L)** & **(mg/L)** & **(mg/L)** & **(mg/L)** & **(mg/L)** & **(mg/L)** & **(mmol/L)** & & & \\ \hline Season (S) & & & & & & & & & \\
2016 & \({}^{\dagger}\) 1488c & 238c & 1377b & 3235b & 0.43b & 2033b & 8.58c & 1.24c & 0.62a \\
2017 & 3116a & 831a & 7459a & 3848a & 1.95a & 3727a & 22.23a & 2.63a & 0.47b \\
2018 & 2270b & 713b & 1028c & 2413c & 0.43b & 2123b & 14.75b & 1.68b & 0.47b \\ Significance & *** & *** & *** & *** & *** & *** & *** & *** & *** \\ \hline Leaf removal (LR) & & & & & & & & & \\ Control & 1788c & 532b & 3155b & 2898b & 1.01a & 2448b & 13.94c & 1.71b & 0.52 \\ North & 2432 ab & 607a & 3105b & 3167 ab & 0.87b & 2692a & 15.62 ab & 1.86a & 0.52 \\ South & 2546a & 616a & 3526a & 3201 ab & 0.94 ab & 2730a & 16.22a & 1.88a & 0.52 \\ North-south & 2401b & 620a & 3367 ab & 3395a & 0.93 ab & 2640a & 15.09b & 1.95a & 0.51 \\ Significance & *** & *** & *** & *** & *** & *** & *** & ns \\ \hline Interaction & & & & & & & & & \\ S*LR & *** & *** & *** & *** & *** & *** & *** & ns \\ \hline \hline \end{tabular}  
* F—flavonoids as (+)-catechin; A—anthocyanins anvalidin-3-glucoside; FRV—flavans reactive with vanillin as (+)-catechin; P—promthocyanindins as cyanidin chloride; TP—total polyphenols as gallic acid; AA—antioxidant activity as TIndex equivalent antioxidant capacity; CI—color intensity; T—tonality. \({}^{\dagger}\) In columns, different letters indicate statistically significant differences at \(p<0.05\). Significance: ns, ** and *** indicate not significant or significant at \(p\leq 0.01\) or \(p\leq 0.001\), respectively.  
\end{table} 
Table 2: Phenolic characteristics of Aglianico wines as a function of season and leaf removal.