## 2 Results and Discussion
### Qualitative Characteristics of Fruit
#### 2.4.2 Aroma Profiles  
Fresh tomato fruit produces several hundred VOCs, some of which are major contributors to the overall aroma and consequently affect consumer experience [33]. Specific pathways are involved in the metabolism of the VOCs, and their concentration in ripe \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Treatment Time** & **Se Spray** & **DW** & **SSC** & **Titrable Acidity** & **Maturity** & **Taste** \\  & **mg L\({}^{-1}\)** & **\%** & \({}^{\circ}\)Brix** & **g Citric Acid 100 mL\({}^{-1}\)** & **Index** & **Index** \\ \hline \multirow{3}{*}{Flowering} & 0 & 4.5 bc & 6.2 c & 0.8 a & 7.5 b & 1 a \\  & 1.0 & 5.4 a & 7.0 a & 0.7 a & 9.4 a & 1 a \\  & 1.5 & 4.8 b & 6.3 bc & 0.6 b & 10.2 a & 0.8 c \\ \hline \multirow{3}{*}{Immuture} & 0 & 4.6 bc & 6.0 c & 0.8 a & 7.6 b & 1 a \\  & 1.0 & 4.2 c & 6.3 bc & 0.7 a & 8.8 a & 0.9 b \\ \cline{1-1}  & 1.5 & 5.3 a & 6.5 b & 0.7 a & 9.4 a & 0.9 b \\ \hline \multicolumn{3}{c}{Variance Analysis} & & & & & \\ \multicolumn{3}{c}{Treatment time (A)} & ** & & & \\ \multicolumn{3}{c}{Set dosage (B)} & ** & & & \\ \multicolumn{3}{c}{Interaction A \(\times\) B} & ** & & & \\ \hline \hline \end{tabular} Significance is as follows: ns, not significant; *, significant at 5\%; **, significant at 1\%; **, significant at 0.1%. Different letters in each column correspond to significantly different values for \(p\)\(<\) 0.05 according to the LSD (least significant difference) test.  
\end{table} 
Table 6: Qualitative characteristics of tomato fruits of the second truss treated with sodium selenate (Na\({}_{2}\)SeO\({}_{4}\)) at different concentrations of selenium and distributed at FL and fruit IG stages. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Treatment Time** & **Se Spray** & **DW** & **SSC** & **Titrable Acidity** & **Maturity** & **Taste** \\  & **mg L\({}^{-1}\)** & **\%** & \({}^{\circ}\)Brix** & **g Citric Acid 100 mL\({}^{-1}\)** & **Index** & **Index** \\ \hline \multirow{3}{*}{Flowering} & 0 & 5.0 c & 6.5 a & 0.8 a & 8.0 a & 1.1 a \\  & 1.0 & 7.1 a & 6.1 a & 0.7 b & 8.5 a & 1 b \\  & 1.5 & 6.5 a & 6.4 a & 0.7 b & 9.3 a & 0.9 b \\ \hline \multirow{3}{*}{Immuture green} & 0 & 5.1 c & 6.3 a & 0.9 a & 8.1 a & 1 a \\  & 1.0 & 6.7 a & 6.4 a & 0.8 ab & 8.4 a & 1 ab \\  & 1.5 & 5.9 b & 6.2 a & 0.7 b & 8.9 a & 0.9 b \\ \hline \multicolumn{3}{c}{Variance Analysis} & & & & \\ \multicolumn{3}{c}{Treatment time (A)} & ** & & & \\ \multicolumn{3}{c}{Set dosage (B)} & ** & & & \\ \multicolumn{3}{c}{Set dosage (B)} & ** & & & \\ \multicolumn{3}{c}{Interaction A \(\times\) B} & ** & & & \\ \hline \hline \end{tabular} Significance is as follows: ns, not significant; *, significant at 5\%; **, significant at 1\%; **, significant at 0.1%. Different letters in each column correspond to significantly different values for \(p\)\(<\) 0.05 according to the LSD (least significant difference) test.  
\end{table} 
Table 5: Qualitative characteristics of tomato fruits of the first truss treated with sodium selenate (Na\({}_{2}\)SeO\({}_{4}\)) at different concentrations of selenium and distributed at FL and fruit IG stages. fruit depends on factors affecting fruit development and physiology. To assess whether Se-enrichment affects this important quality trait, we carried out specific VOC analyses on red-ripe fruit of the second truss from the control and from plants treated with 1.0 and 1.5 Se L\({}^{-1}\) at FL. A total of 39 VOCs were identified in the three sets of samples (Supplementary material, Table S1). Partial least squares regression analysis indicated that sodium selenate treatment affects the volatile profile of the tomatoes at ripening (Figure 1). Overall, the validated PLSDA (Partial least squares discriminant analysis) model explains about 90% (first and second factors together) of the variability recorded between sample groups. In fact, a clear segregation of the different treatments was observed, with Se-enriched samples clustering separately from the control tomatoes and from each other.