## 4 Conclusions  
In this study, the effect of Ca and Si foliar treatments applied to the vineyard either as single elements or in combination was assessed on the Tempranillo grape quality and chemical composition. A slight effect was observed with respect to general must parameters. Regarding aroma composition, the foliar application of Ca + Si increased the total concentration of all the aromatic compounds families evaluated. Foliar Ca sprays enhanced the total terpenoid and total benzenoid concentrations, while Si foliar application only \begin{table}
\begin{tabular}{c c c c c} \hline  & **Control** & **Ca** & **Si** & **Ca + Si** \\ \hline Aspartic acid (Asp) & 12.49 \(\pm\) 0.45 a & 14.59 \(\pm\) 1.41 a & 15.57 \(\pm\) 2.31 a & 19.37 \(\pm\) 1.10 b \\ Glutamic acid (Glu) & 21.47 \(\pm\) 3.69 a & 32.89 \(\pm\) 6.33 b & 29.34 \(\pm\) 2.71 ab & 35.82 \(\pm\) 6.34 b \\ Asparagine (Asn) & 1.85 \(\pm\) 0.12 a & 2.72 \(\pm\) 0.04 b & 1.82 \(\pm\) 0.26 a & 3.86 \(\pm\) 0.16 c \\ Serine (Ser) & 27.13 \(\pm\) 2.48 a & 38.85 \(\pm\) 7.02 b & 30.79 \(\pm\) 2.74 ab & 31.36 \(\pm\) 3.54 ab \\ Histidine (His) & 13.69 \(\pm\) 2.79 a & 31.33 \(\pm\) 12.12 ab & 13.93 \(\pm\) 1.00 a & 37.87 \(\pm\) 18.12 b \\ Glycine (Gly) & 2.02 \(\pm\) 1.71 a & 5.40 \(\pm\) 0.16 b & 5.20 \(\pm\) 0.60 b & 5.18 \(\pm\) 0.12 b \\ Threonine (Thr) & 34.10 \(\pm\) 2.02 a & 54.43 \(\pm\) 4.71 c & 40.60 \(\pm\) 7.09 ab & 47.28 \(\pm\) 8.83 bc \\ Citrulline (Cit) & 4.86 \(\pm\) 0.47 a & 8.83 \(\pm\) 1.55 a & 8.27 \(\pm\) 2.94 a & 19.47 \(\pm\) 7.20 b \\ Argin (Arg) & 559.42 \(\pm\) 40.36 a & 745.72 \(\pm\) 178.86 a & 708.59 \(\pm\) 81.93 a & 587.11 \(\pm\) 156.69 a \\ Alanine (Ala) & 58.21 \(\pm\) 18.68 a & 93.29 \(\pm\) 3.97 b & 84.24 \(\pm\) 6.84 b & 88.15 \(\pm\) 10.66 b \\ \(\gamma\)-Aminobutyric acid (Gaba) & 137.71 \(\pm\) 19.97 a & 152.83 \(\pm\) 16.78 a & 166.01 \(\pm\) 19.39 a & 169.63 \(\pm\) 5.92 a \\ Tyrosine (Tyr) & n.d. & n.d. & n.d. & n.d. \\ Cysteine (Cys) & n.d. & n.d. & n.d. & n.d. \\ Valine (Val) & 4.43 \(\pm\) 0.59 a & 23.00 \(\pm\) 3.55 c & 11.50 \(\pm\) 0.07 b & 22.08 \(\pm\) 0.11 c \\ Methionine (Met) & 3.42 \(\pm\) 1.01 a & 9.35 \(\pm\) 1.78 c & 5.23 \(\pm\) 0.37 ab & 7.28 \(\pm\) 1.63 bc \\ Tryptophan (Trp) & 21.05 \(\pm\) 2.06 a & 29.00 \(\pm\) 3.24 b & 22.73 \(\pm\) 2.94 ab & 24.84 \(\pm\) 2.90 ab \\ Phenylalanine (Phe) & 4.88 \(\pm\) 0.57 a & 9.42 \(\pm\) 0.72 b & 9.55 \(\pm\) 1.35 b & 9.75 \(\pm\) 0.60 b \\ Isoleucine (Ile) & 2.94 \(\pm\) 0.46 a & 13.65 \(\pm\) 2.09 c & 5.58 \(\pm\) 0.55 b & 13.09 \(\pm\) 0.29 c \\ Ornithine (Orm) & 2.12 \(\pm\) 0.89 a & 3.58 \(\pm\) 0.70 a & 2.89 \(\pm\) 0.28 a & 2.50 \(\pm\) 0.65 a \\ Leucine (Leu) & 5.71 \(\pm\) 0.70 a & 22.51 \(\pm\) 4.77 b & 9.52 \(\pm\) 1.85 a & 18.74 \(\pm\) 1.90 b \\ Lysine (Lys) & 2.07 \(\pm\) 0.03 a & 3.20 \(\pm\) 0.58 b & 2.63 \(\pm\) 0.43 ab & 1.73 \(\pm\) 0.41 a \\ Proline (Pro) & 295.23 \(\pm\) 41.76 a & 373.10 \(\pm\) 28.58 b & 357.07 \(\pm\) 16.24 b & 358.02 \(\pm\) 28.96 b \\ _Total amino acids_ & _1214.78_ \(\pm\) 42.53 a & _1666.82_ \(\pm\) _232.04 b_ & _1525.07_ \(\pm\) _72.80 b_ & _1504.02_ \(\pm\) _101.89 b_ \\ _Total amino acids without Pro_ & _919.55_ \(\pm\) 32.39 a_ & _1293.71_ \(\pm\) _220.99 b_ & _1168.00_ \(\pm\) _66.85 ab_ & _1145.13_ \(\pm\) _121.64 ab_ \\ \hline \end{tabular}
\end{table} 
Table 4: Amino acid concentration (mg/L) in musts from control and Ca, Si and Ca + Si foliar treatments. increased the total benzenoid concentration. Further studies on the foliar application of Ca and Si in vineyards should be carried out to clarify their effect on the grape phenolic composition. The effect of foliar treatments may vary depending on grape variety, as derived from the limited enhancement of grape phenolic content recorded in this investigation, compared with previous studies performed with other cultivars. In addition, no clear synergistic effect was observed between Ca and Si treatments to improve grape phenolic compound concentrations.