## 3 Results and Discussion
### Variability of Chemical Constituents
#### 3.2.1 Taro
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & & & \multicolumn{4}{c}{**Calibration Set**} & \multicolumn{4}{c}{**Validation**} \\  & & & & & & & & & & **Independent Set** \\ \hline
**Sweet Potato** & **n** & **Outliers** & **Mean** & **SD** & **PLS Terms** & **SEC** & **SECV** & \(\mathbf{r^{2}}_{\text{cv}}\) & **RPD** & **n** & \(\mathbf{r^{2}}_{\text{pred}}\) & **SEP** \\ \hline  & & & \multicolumn{4}{c}{Moisture, g/100g DW} & \\ \hline Tuber & 105 & 7 & 5.066 & 1.539 & 9 & 0.670 & 0.761 & 0.755 & 2.02 & 24 & 0.532 & 0.822 \\ Shoot & 111 & 0 & 6.114 & 1.083 & 9 & 0.616 & 0.701 & 0.584 & 1.54 & 24 & 0.495 & 0.945 \\ \hline  & & & \multicolumn{4}{c}{Protein, g/100g DW} & \\ \hline Tuber & 105 & 9 & 6.038 & 1.262 & 9 & 0.112 & 0.114 & 0.992 & 11.10 & 24 & 0.994 & 0.099 \\ Shoot & 111 & 9 & 14.480 & 3.160 & 9 & 0.218 & 0.244 & 0.994 & 12.96 & 24 & 0.995 & 0.274 \\ \hline  & & & \multicolumn{4}{c}{Nitrogen, g/100g DW} & \\ \hline Tuber & 105 & 11 & 0.973 & 0.203 & 9 & 0.022 & 0.024 & 0.986 & 8.47 & 24 & 0.994 & 0.016 \\ Shoot & 111 & 9 & 2.318 & 0.506 & 9 & 0.035 & 0.039 & 0.994 & 12.96 & 24 & 0.995 & 0.044 \\ \hline  & & & \multicolumn{4}{c}{Starch, g/100g DW} & \\ \hline Tuber & 105 & 3 & 42.509 & 4.122 & 9 & 1.430 & 1.608 & 0.847 & 2.56 & 24 & 0.856 & 0.944 \\ Shoot & 111 & 4 & 4.944 & 2.599 & 9 & 0.487 & 0.517 & 0.961 & 5.03 & 24 & 0.981 & 0.323 \\ \hline  & & & \multicolumn{4}{c}{Minerals, g/100g DW} & \\ \hline Tuber & 105 & 8 & 4.336 & 0.482 & 9 & 0.082 & 0.089 & 0.966 & 5.40 & 24 & 0.868 & 0.158 \\ Shoot & 111 & 8 & 11.266 & 1.800 & 9 & 0.215 & 0.221 & 0.985 & 8.16 & 24 & 0.992 & 0.171 \\ \hline  & & & \multicolumn{4}{c}{CaOx, g/100g DW} & \\ \hline Tuber & 105 & 8 & 0.058 & 0.034 & 9 & 0.012 & 0.014 & 0.826 & 2.41 & 24 & 0.865 & 0.020 \\ Shoot & 111 & 3 & 0.099 & 0.079 & 9 & 0.027 & 0.029 & 0.866 & 2.74 & 24 & 0.960 & 0.014 \\ \hline  & & & \multicolumn{4}{c}{Total carbon, g/100g DW} & \\ \hline Tuber & 105 & 6 & 40.341 & 0.333 & 9 & 0.173 & 0.185 & 0.687 & 1.79 & 24 & 0.705 & 0.176 \\ Shoot & 111 & 6 & 41.510 & 0.572 & 9 & 0.220 & 0.238 & 0.826 & 2.40 & 24 & 0.914 & 0.232 \\ \hline  & & & \multicolumn{4}{c}{\(\delta^{13}\)C, \%\({}_{\infty}\) DW} & \\ \hline Tuber & 105 & 6 & \(-25.065\) & 1.161 & 9 & 0.306 & 0.364 & 0.901 & 3.19 & 24 & 0.178 & 0.602 \\ Shoot & 111 & 6 & \(-26.611\) & 1.257 & 9 & 0.257 & 0.265 & 0.956 & 4.75 & 24 & 0.579 & 0.311 \\ \hline  & & & \multicolumn{4}{c}{\(\Delta^{13}\)C, \%\({}_{\infty}\) DW} & \\ \hline Tuber & 105 & 6 & 17.505 & 1.211 & 9 & 0.319 & 0.380 & 0.901 & 3.18 & 24 & 0.629 & 0.174 \\ Shoot & 111 & 6 & 19.121 & 1.314 & 9 & 0.269 & 0.277 & 0.956 & 4.75 & 24 & 0.580 & 0.325 \\ \hline  & & & \multicolumn{4}{c}{\(\delta^{15}\)N, \% DW} & \\ \hline Tuber & 105 & 0 & 4.586 & 1.120 & 9 & 0.533 & 0.584 & 0.727 & 1.92 & 24 & 0.769 & 0.499 \\ Shoot & 111 & 5 & 4.185 & 1.097 & 9 & 0.260 & 0.274 & 0.938 & 4.01 & 24 & 0.788 & 0.345 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Quality constituent statistics for calibration and independent validation models of sweet potato (_Ipomooata batatas_ (L.) Lam.) accessions flour under drought conditions. stiffness during drought [52]. The forms from both trials had the significantly highest M accumulation (\(p\leq 0.05\)), compared with shoots. Meanwhile, N increase was only significative (\(p\leq 0.05\)) in corms from the second trial. M and N increase photosynthesis and protein synthesis as plant responses to drought, allocating nutrients between the plant organs [42; 53]. Drought increased CaOx-comr in both trials, but a CaOx-shoot increase only occurred in the second trial. The increase in this insoluble oxalate could help the plant osmoregulation under water scarcity conditions, through the adjustment of oxalic acid synthesized by photosynthesis oxidative processes or carbohydrate metabolism [47].