## 3 Results and Discussion
### Evaluation of the Ability of Various Features to Identify Fusarium Head Blight
#### 3.1.3 Vegetation Indices  
Information about infected wheat was extracted via commonly used vegetation indices in this research. The vegetation indices are strongly correlated with the severity of the disease (\(p\)-value \(<\) 0.001) and the absolute values of correlation coefficients are greater than 0.7 (\(|\)R\(|\)\(>\) 0.7), as shown in Table 7. The sensitive vegetation indices for front samples are NDVI, NBNDVI, NRI, PSRI, SIPI, NPCI, MSR, and GI; for side samples are NDVI, NBNDVI, NRI, PSRI, SIPI, NPCI, and MSR; and for erect samples are NDVI, NBNDVI, PSRI, SIPI, and MSR.  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \multirow{2}{*}{**Features**} & \multicolumn{3}{c}{**Front**} & \multicolumn{3}{c}{**Side**} & \multicolumn{3}{c}{**Erect**} \\ \cline{2-10}  & **R** & **R2** & \(p\)**-Value** & **R** & **R2** & \(p\)**-Value** & **R** & **R2** & \(p\)**-Value** \\ \hline \(\lambda\) & \(-\)0.234 & 0.055 & 0.027 & \(-\)0.01 & 0.000 & 0.926 & 0.352 & 0.124 & 0.001 \\ Band depth & \(-\)0.761 & 0.579 & 0.000 & \(-\)0.802 & 0.644 & 0.000 & \(-\)0.699 & 0.489 & 0.000 \\ W1 & \(-\)0.234 & 0.055 & 0.027 & \(-\)0.010 & 0.000 & 0.926 & 0.352 & 0.124 & 0.001 \\ W2 & 0.234 & 0.055 & 0.027 & 0.010 & 0.000 & 0.926 & \(-\)0.352 & 0.124 & 0.001 \\ Area & \(-\)0.710 & 0.504 & 0.000 & \(-\)0.772 & 0.595 & 0.000 & \(-\)0.665 & 0.443 & 0.000 \\ \hline \end{tabular} Note: R is the correlation coefficient; R2 is the determination coefficient.  
\end{table}
Table 6: Correlation between continuum removal features and disease severity.  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \multirow{2}{*}{**Features**} & \multicolumn{3}{c}{**Front**} & \multicolumn{3}{c}{**Side**} & \multicolumn{3}{c}{**Erect**} \\ \cline{2-10}  & **R** & **R2** & \(p\)**-Value** & **R** & **R2** & \(p\)**-Value** & **R** & **R2** & \(p\)**-Value** \\ \hline (SDr-SDb)/(SDr+SDb) & 0.349 & 0.122 & 0.001 & 0.087 & 0.008 & 0.419 & \(-\)0.023 & 0.001 & 0.829 \\ (SDr-SDy)/(SDr+SDy) & \(-\)0.816 & 0.665 & 0.000 & \(-\)0.781 & 0.610 & 0.000 & \(-\)0.787 & 0.619 & 0.000 \\ (SDr-SDg)/(SDr+SDg) & 0.475 & 0.226 & 0.000 & 0.229 & 0.053 & 0.031 & 0.128 & 0.016 & 0.176 \\ (SDy-SDb)/(SDr+SDb) & 0.782 & 0.612 & 0.000 & 0.742 & 0.551 & 0.000 & 0.135 & 0.018 & 0.206 \\ (SDg-SDb)/(SDg+SDb) & \(-\)0.793 & 0.629 & 0.000 & \(-\)0.833 & 0.693 & 0.000 & \(-\)0.757 & 0.573 & 0.000 \\ \hline \end{tabular} Note: R is the correlation coefficient; R2 is the determination coefficient.  
\end{table}
Table 5: _Cont._  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \multirow{2}{*}{**Vegetation Index**} & \multicolumn{3}{c}{**Front**} & \multicolumn{3}{c}{**Side**} & \multicolumn{3}{c}{**Erect**} \\ \cline{2-10}  & **R** & **R2** & \(p\)**-Value** & **R** & **R2** & \(p\)**-Value** & **R** & **R2** & \(p\)**-Value** \\ \hline PRI & \(-\)0.640 & 0.410 & 0.000 & \(-\)0.659 & 0.434 & 0.000 & \(-\)0.526 & 0.277 & 0.000 \\ PHRI & \(-\)0.382 & 0.146 & 0.000 & \(-\)0.194 & 0.038 & 0.069 & \(-\)0.007 & 0.000 & 0.949 \\ MCARI & \(-\)0.646 & 0.418 & 0.000 & \(-\)0.632 & 0.400 & 0.000 & \(-\)0.628 & 0.395 & 0.000 \\ TVI & \(-\)0.623 & 0.388 & 0.000 & \(-\)0.565 & 0.319 & 0.000 & \(-\)0.410 & 0.168 & 0.000 \\ ARI & 0.142 & 0.020 & 0.183 & \(-\)0.157 & 0.025 & 0.141 & \(-\)0.347 & 0.121 & 0.001 \\ NDVI & \(-\)0.739 & 0.546 & 0.000 & \(-\)0.800 & 0.640 & 0.000 & \(-\)0.714 & 0.510 & 0.000 \\ GNDVI & \(-\)0.375 & 0.141 & 0.000 & \(-\)0.537 & 0.288 & 0.000 & \(-\)0.530 & 0.281 & 0.000 \\ NBNDVI & \(-\)0.758 & 0.574 & 0.000 & \(-\)0.811 & 0.657 & 0.000 & \(-\)0.723 & 0.522 & 0.000 \\ NRI & \(-\)0.796 & 0.633 & 0.000 & \(-\)0.732 & 0.536 & 0.000 & \(-\)0.319 & 0.102 & 0.002 \\ \hline \end{tabular}
\end{table}
Table 7: Correlation between vegetation indices and disease severity.