## 2 Results and Discussion
### Multivariate Analyses of Metabolites in the Five Rice Varieties
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Differential Metabolites** & **RT [min]** & \(p\)**-Value** & **VIP** \\ \hline Cyclopropanecarboxylic acid oct-3-en-2-yl ester & 13.71 & 0.01617 & 2.42 \\
4-_tert_-Butoxystyrene & 37.17 & \(3.46\times 10^{-7}\) & 2.32 \\
2-Methyl-2-octen-4-ol & 26.50 & \(2.27\times 10^{-5}\) & 2.29 \\ Aniline & 11.27 & \(7.85\times 10^{-7}\) & 2.29 \\
2-Methylfuran, & 23.33 & \(2.14\times 10^{-8}\) & 2.27 \\ N-(1,1-Dimethylprop-2-ynyl)-acetamide & 18.00 & 0.000164 & 2.21 \\
4-Ethyl-4-\(H\)-1,2,4-triazole & 4.98 & 0.006118 & 2.16 \\
3-Methyl-2-butenal & 10.58 & \(6.18\times 10^{-6}\) & 2.13 \\
1,3-Dichloro-2-methylbenzene & 19.75 & \(9.93\times 10^{-10}\) & 2.08 \\ DAO vs. PU & & & \\
4,8-Dimethylundecane & 10.76 & 0.00596 & 6.23 \\
2-Isopropyl-5-methyl-9-methylphenicyclo[4.4.0]dec-1-ene & 21.43 & 0.015716 & 5.23 \\
2-Acetyl-1-pyrroline & 14.64 & \(3.82\times 10^{-7}\) & 4.09 \\ Butyl benzoate & 27.34 & \(4.87\times 10^{-5}\) & 4.08 \\
3-Isopropyl-1,1,7,7,7-hexamethyl-3,5,5-tris(trimethylsiloxy)tetrasiloxane & 19.53 & \(2.65\times 10^{-9}\) & 3.58 \\ Dodecamethylcyclohexasiloxane & 15.17 & \(1.24\times 10^{-10}\) & 3.46 \\
1-Ethyl-5-methylcyclopentene & 4.59 & \(2.14\times 10^{-7}\) & 3.16 \\ Sulfurous acid dodecyl pentyl ester & 16.81 & 0.000194 & 3.16 \\
1-Ethenylazirdine & 5.45 & \(6.88\times 10^{-8}\) & 2.99 \\
2-Methyldecane & 7.90 & 0.002899 & 2.97 \\
1-(1\(H\)-pyrrol-2-yl)ethanone & 29.47 & \(1.36\times 10^{-6}\) & 2.77 \\
2-Butyl-2-octenal & 23.12 & \(4.04\times 10^{-6}\) & 2.74 \\ Acetoin & 13.11 & 0.003984 & 2.73 \\
3-Nonen-2-one & 19.32 & 0.025678 & 2.71 \\
1,3-Dichloro-2-methylbenzene & 19.75 & \(7.24\times 10^{-5}\) & 2.65 \\
1,2-Dimethoxybenzene & 24.32 & \(5.15\times 10^{-7}\) & 2.63 \\
2-Bromocycloheptanone & 17.66 & \(1.40\times 10^{-6}\) & 2.61 \\
2-Methylfuran & 23.33 & \(1.03\times 10^{-9}\) & 2.56 \\
2,4,6-Trimethyldecane & 6.06 & \(1.34\times 10^{-9}\) & 2.52 \\
5-Methyl-2-(1-methylylethyl)-2-Cyclohexen-1-one & 23.68 & \(2.08\times 10^{-5}\) & 2.51 \\
1-Butanol & 9.29 & \(4.94\times 10^{-8}\) & 2.42 \\
2-Ethyl-2-(hydroxymethyl)-1,3-propanediol & 14.11 & \(1.56\times 10^{-5}\) & 2.40 \\
2,5-Dimethyl-2,4-hexadiene & 5.92 & \(1.88\times 10^{-6}\) & 2.40 \\
2-(1-Cyclopent-1-enyl-1-methylethyl)cyclopentanone & 25.27 & 0.006072 & 2.39 \\
4-(5-Methyl-2-furanyl)-2-butanone & 23.44 & \(3.10\times 10^{-5}\) & 2.34 \\
3-3-Dimethylcyclohexanol & 19.28 & 0.000241 & 2.33 \\ \(n\)-Butylbenzene & 13.93 & 0.129919 & 2.28 \\ (\(E\))-\(\mathrm{\acute{E}}\)-Hexenal & 11.16 & 0.006958 & 2.24 \\
5-Ethyl-2-decen-4-one & 23.50 & \(3.04\times 10^{-5}\) & 2.22 \\
2-Propenoic acid butyl ester & 10.00 & 0.000258 & 2.19 \\ YE vs. DAO & & & \\ Butyl benzoate & 27.34 & \(2.51\times 10^{-9}\) & 5.92 \\
1(\(S\)-\(exo\))-2-Methyl-3-methylene-2-(4-methyl-3-pentenyl)bicyclo[2.2.1]heptane & 22.69 & \(2.61\times 10^{-7}\) & 4.76 \\ DL-2-Phenyl-1,2-propanediol & 25.13 & \(4.35\times 10^{-5}\) & 4.24 \\
2-Acetyl-1-pyrroline & 14.64 & \(0.003009\) & 4.14 \\
1,3-Dichloro-2-methylbenzene & 19.75 & \(3.05\times 10^{-7}\) & 4.05 \\ Sulfurous acid dodecyl pentyl ester & 16.81 & 0.000667 & 3.70 \\
2-Butyl-2-octenal & 23.12 & 0.002661 & 3.55 \\
2-Methyldecane & 7.90 & 0.006932 & 3.36 \\
2-(1-Cyclopent-1-enyl-1-methylethyl)cyclopentanone & 25.27 & 0.006072 & 3.28 \\ Dimethylsalenoid & 23.08 & 0.053691 & 2.99 \\ Propanoic acid, 2-methyl-, 3-hydroxy-2,2,4-trimethylpentyl ester & 27.52 & \(4.85\times 10^{-7}\) & 2.95 \\ Aziridine, 1-ethenyl- & 5.45 & 0.000476 & 2.95 \\
2-Oeten-4-ol, 2-methyl- & 26.50 & \(2.27\times 10^{-5}\) & 2.94 \\ Undecane, 4,8-dimethyl- & 10.76 & 0.22725 & 2.82 \\
6,6-Dimethyl-cyclohex-2-en-1-ol & 26.87 & \(4.96\times 10^{-5}\) & 2.55 \\
3-Nonen-2-one & 19.32 & 0.017839 & 2.55 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._