## 4 Arinto  
For Arinto grapes, the effect of the harvest year accounted for 62.2% of total data set variance (Table 4). The first component of the scores plot separates the 2010 harvest (placed in PC1 positive) from the others (placed in PC1 negative), while the second component separates the 2011 (PC2 negative) and 2012 (PC2 positive) harvests (Figure 4a). According to the separation along PC1, 2010 grapes had lower berry weight and pH and higher phenolic content and higher diversity and number of volatiles (Figure 4c). The latter comprised mono- and sesquiterpene oxygen-containing compounds, such as dihydromyrcenol, dihydrolinalool, nerolidol, and \(\beta\)-eudesmol, and C\({}_{13}\) norisoprenoids, mainly TDN and \(\beta\)-damascenone (isomer 2). Additionally, the separation along PC2 of grapes from 2011 and 2012 harvests was mostly due to the higher content of six monoter-penic compounds (limonene, 1,8-cineole, linalool oxide, fenchol, borneol, and menthol) in grapes from 2012, while \(\alpha\)-terpinolene and rose oxide (isomer 1) were higher in 2011 grapes. Varietal compounds are secondary plant metabolites modulated by the temperature and precipitation amount [61]. These results revealed that 2010 weather conditions seem to favor the Arinto varietal compound formation, suggesting that grapes from the 2010 harvest have higher aroma potential compared to the other two harvests. Additionally, three C\({}_{6}\) aldehydes (hexanal, 2-hexenal, and 2,4-hexadienal) were determined in higher amounts in grapes from 2010, while higher content of two C\({}_{6}\) alcohols (2- and 3-hexen-1-ol) was determined in grapes from 2012. The formation of C\({}_{6}\) aldehydes and their reduction to the corresponding alcohols depends on the content of unsaturated lipids present in grapes and on the activities of lipoxygenase and alcohol dehydrogenase enzymes [61]. All these observations suggested that both the dry and warm conditions of 2011 and the fresher and rainier ones observed in 2012 (Figure 2) diminished Arinto grapes' content of phenolics and volatiles. Previous works showed that high temperatures promoted significant reductions of the phenolic content of Cabernet-Sauvignon [62] and Merlot [63] grape varieties, as well as aroma quality losses [55], while higher precipitation promotes a decrease in the concentration of phenolics [64] and volatiles [9]. The effect of parcel characteristics on Arinto grapes accounted for 14.9% of the total data set variance (Table 4). Scores and loading plots are shown in Figure 4b,d, respectively. PC1 distinguishes AR-VA2, placed on the positive side of PC1, from the other two parcels, placed on the negative side of PC1 (AR-VA1) or near to the origin (AR-SM1) (Figure 4b). The same number of volatile compounds was found in grapes from all parcels (a total of 66 individual compounds); thus, the separation observed in the loadings plot (Figure 4d) was due to the different amounts determined for most of the varietal volatile compounds, in particular, monoterpene ones, including free and glycosylated linked fractions, as well \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Variety** & **Factors** &
\begin{tabular}{c} _p-Value_ \\ **(2000 Permutations)** \\ \end{tabular} & **Explaned Variance (\%)** \\ \hline Arinto & Harvest year & \textless{}0.0005 & 62.2 \\  & Vineyard parcel & 0.0390 & 14.9 \\ Bical & Harvest year & \textless{}0.0005 & 53.8 \\  & Vineyard parcel & 0.0135 & 17.1 \\ Sauvignon Blanc & Harvest year & \textless{}0.0005 & 68.2 \\  & Vineyard parcel & \textgreater{}0.05 * & 11.9 \\ Baga & Harvest year & \textless{}0.0005 & 61.4 \\  & Vineyard parcel & 0.040 & 14.8 \\ Castelão & Harvest year & \textless{}0.0005 & 66.7 \\  & Vineyard parcel & 0.041 & 15.5 \\ Touriga Nacional & Harvest year & \textless{}0.0005 & 59.3 \\  & Vineyard parcel & 0.0105 & 18.8 \\ \hline \hline \end{tabular}  
* _p-value > 0.05 (no significance)._  
\end{table} 
Table 4: Significance testing of factors harvest and parcel, for _V. vinifera_ cv.