## 4 Conclusions  
The most abundant macromineral in cassava storage roots was found to be potassium (K), and the lowest was sodium (Na). It implies that cassava, with a high level of K and low Na, might be an ideal crop to consume to reduce hypertension, although this needs further clinical evidence. The most abundant microelement was manganese (Mn), and the least abundant microelements were molybdenum (Mo) and cobalt (Co). The genotype and method had a strong influence on the concentrations of the macro- and microelements in yellow-fleshed cassava roots. Most of the genotypes had higher levels of mineral density than the check varieties, which are white-fleshed, and they could be advanced to the next stage in the breeding program. Genotype 00/0028 had a high level of most of the minerals, especially Fe, Zn, Mn, and B, and could be considered to be an outstanding genotype. It could be concluded that harvesting time plays a significant role in the concentration level of some macro- and microelements in cassava roots while showing no effect on some. However, it was confirmed that yellow-fleshed roots contained more macro- and microelements than the white-fleshed roots. Method 1 (where samples were taken from all the parts and averaged) was found to be the best, but it is not cost-effective. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Variables** & **Fe** & **Mn** & **B** & **Cu** & **Mo** & **Co** & **Ni** & **Zn** & **Al** \\ \hline Trial set 1 & & & & & & & & & \\ Fe & 1.00 *** & 0.391 *** & 0.345 *** & 0.056 & 0.026 & \(-0.029\) & \(-0.22\)*** & 0.178 *** & 0.425 *** \\ Mn & 0.392 *** & 1.00 *** & 0.539 *** & 0.184 *** & \(-0.053\) & 0.05 & 0.16 * & 0.322 *** & 0.042 \\ B & 0.345 *** & 0.539 *** & 1.00 *** & 0.22 *** & \(-0.161\) *** & \(-0.112\) & 0.001 & 0.297 *** & \(-0.084\) \\ Cu & 0.056 & 0.184 *** & 0.22 *** & 1.00 *** & \(-0.071\) & \(-0.032\) & 0.316 *** & 0.377 *** & \(-0.186\) *** \\ Mo & 0.026 & \(-0.052\) & \(-0.161\) * & \(-0.071\) & 1.00 *** & 0.457 *** & \(-0.063\) & \(-0.084\) & 0.401 *** \\ Co & \(-0.029\) & 0.05 & \(-0.112\) & \(-0.032\) & 0.457 *** & 1.00 *** & 0.066 & \(-0.036\) & 0.183 ** \\ Ni & \(-0.022\) *** & 0.16 * & 0.001 & 0.316 *** & \(-0.063\) & 0.066 & 1.00 *** & 0.198 *** & \(-0.228\) *** \\ Zn & 0.178 *** & 0.322 *** & 0.297 *** & 0.377 *** & \(-0.084\) & \(-0.036\) & 0.189 *** & 1.00 *** & \(-0.141\) * \\ Al & 0.424 *** & 0.042 & \(-0.084\) & \(-0.186\) *** & 0.401 *** & 0.183 ** & \(-0.228\) *** & \(-0.141\) * & 1.00 *** \\ Trial set 2 & & & & & & & & & \\ Fe & 1.00 *** & 0.419 *** & 0.663 *** & 0.341 *** & 0.64 *** & 0.625 *** & 0.389 *** & 0.229 *** & 0.536 *** \\ Mn & 0.419 *** & 1.00 *** & 0.434 *** & 0.246 *** & 0.431 *** & 0.446 *** & 0.262 *** & 0.618 *** & 0.177 * \\ B & 0.663 *** & 0.434 *** & 1.00 *** & 0.32 *** & 0.789 *** & 0.783 *** & 0.363 *** & 0.249 *** & 0.532 *** \\ Cu & 0.341 *** & 0.246 *** & 0.32 *** & 1.00 *** & 0.256 *** & 0.266 *** & 0.142 & 0.26 *** & 0.183 * \\ Mo & 0.64 *** & 0.431 *** & 0.789 *** & 0.256 *** & 1.00 *** & 0.991 *** & 0.27 *** & 0.27 *** & 0.603 *** \\ Co & 0.625 *** & 0.446 *** & 0.783 *** & 0.266 *** & 0.991 *** & 1.00 *** & 0.27 *** & 0.283 *** & 0.604 *** \\ Ni & 0.389 *** & 0.262 *** & 0.363 *** & 0.142 & 0.27 *** & 0.27 *** & 1.00 *** & 0.052 & 0.089 \\ Zn & 0.229 *** & 0.618 *** & 0.249 *** & 0.26 *** & 0.27 *** & 0.283 *** & 0.052 & 1.00 *** & 0.069 \\ Al & 0.536 *** & 0.177 * & 0.532 *** & 0.183 * & 0.603 *** & 0.604 *** & 0.089 & 0.069 & 1.00 *** \\ \hline \hline \end{tabular}  
* ns, not significant at \(p<0.05\), *, significant \(p<0.05\), **, significant at \(p<0.01\); ***, significant at \(p<0.001\).  
\end{table} 
Table 9: Pearson correlation coefficients of the micromineral contents of yellow cassava roots (dataset 1 and 2). Method 2 could be the best alternative because it is cost-effective but is not as accurate as method 1. The positively correlated elements could be bred together by breeders for improvements of the macro- and microelements in cassava roots.