## 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 (1S-exo)-2-Methyl-3-methylene-2-(4-methyl-3-pentenyl)bicyclo[2.2.1]heptane & 22.69 & 0.000391 & 2.64 \\ -(Octyloxy)ethanol & 7.83 & \(1.18\times 10^{-5}\) & 2.56 \\
2-Propylthiophene & 16.71 & 0.003933 & 2.49 \\
3,5,5-Trimethyl 2(5H)-furanone & 20.85 & \(1.26\times 10^{-6}\) & 2.42 \\ Nonanoic acid ethyl ester & 20.03 & 0.111112 & 2.39 \\
2-Methyl-2-octen-4-ol & 26.50 & \(4.19\times 10^{-5}\) & 2.36 \\ Succinic acid but-3-yn-2-yl 2-methylpent-3-yl ester & 15.49 & \(3.62\times 10^{-6}\) & 2.35 \\
2-Ethylheptanoic acid & 26.99 & 0.003497 & 2.34 \\ N,N-2,2-Tetramethyl-1,3-propanediamine & 1.86 & 0.028851 & 2.30 \\ Acetoin & 13.11 & 0.000493 & 2.27 \\
3-Cyano-3-methyl-4-oxopentanamide & 29.50 & \(1.21\times 10^{-5}\) & 2.24 \\
3-Butene-1,2-diol & 8.35 & \(6.70\times 10^{-6}\) & 2.22 \\
1-Ethenylaziridine & 5.45 & 0.000907 & 2.13 \\ (5)- N,N-2-Trimethyl-2-[(2,2,3-trimethyl-1-pyrrolidin)oxy]-1-propanamine & 24.34 & \(3.86\times 10^{-6}\) & 2.12 \\
1-Ethyl-5-methylcyclopentene & 4.59 & \(1.95\times 10^{-7}\) & 2.09 \\
10-Methylnonadecane & 8.20 & \(5.06\times 10^{-9}\) & 2.08 \\ Dibbutoxymethane & 11.28 & \(2.33\times 10^{-5}\) & 2.08 \\
1-(2-Furanyl)1-propanone & 7.74 & 0.016649 & 2.07 \\
2-Cyclohexylpiperidine & 23.57 & 0.000879 & 2.04 \\ (Z)-2-Octen-1-ol, & 21.96 & 0.020305 & 2.02 \\ Butanoic acid butyl ester & 11.32 & 0.003751 & 2.02 \\
3-Butylbenzene & 10.76 & 0.055871 & 4.87 \\
2-Isopropyl-5-methyl-9-methylenebicyclo[4.4.0]dec-1-ene & 21.43 & 0.037269 & 4.63 \\ Dodecamethylcyclohexassiloxane & 15.17 & \(2.01\times 10^{-9}\) & 4.23 \\
3-Isopropyl-1,1,1,7,7,7-hexamethyl-3,5,5-tris(trimethylsiloxy)tetrasiloxane & 19.53 & \(1.55\times 10^{-9}\) & 4.09 \\ (1S-exo)-2-methyl-3-methylene-2-(4-methyl-3-pentenyl)bicyclo[2.2.1]heptane & 22.69 & \(2.61\times 10^{-7}\) & 4.00 \\
1,2-Dimethoxybenzene & 24.32 & \(6.97\times 10^{-6}\) & 3.86 \\
2-Propenoic acid butyl ester & 10.00 & 0.000127 & 3.26 \\ \(n\)-Butylbenzene & 13.93 & 0.071271 & 3.25 \\
3-Butylpyridine-1-oxide & 20.20 & 1.06 \(\times 10^{-8}\) & 3.11 \\
3,3-Dimethylcyclohexanol & 19.28 & \(2.22\times 10^{-8}\) & 3.06 \\
2,6,7-Trimethyldecane & 6.03 & 0.352155 & 2.85 \\ Propanoic acid butyl ester & 8.96 & 0.001745 & 2.81 \\
2,4,6-Trimethyldecane & 6.06 & \(7.58\times 10^{-8}\) & 2.76 \\
2-Ethyl-2-(hydroxymethyl)-1,3-propanediol & 14.11 & \(2.72\times 10^{-6}\) & 2.69 \\ Indole & 37.99 & 0.000491 & 2.66 \\ Acetic acid butyl ester & 6.97 & \(1.66\times 10^{-5}\) & 2.64 \\ DL-2-Phenyl-1,2-propanediol & 25.13 & \(3.78\times 10^{-5}\) & 2.64 \\ Dimethylsilanediol & 23.08 & 0.047035 & 2.62 \\
1-\(sec\)-Butyl-3-nitro-4-amino-1,2,5-triazoleole 2-oxide & 13.53 & 0.017105 & 2.58 \\
2-Methylfuran & 23.33 & \(2.20\times 10^{-9}\) & 2.50 \\
3-Octen-2-one & 16.60 & 0.001749 & 2.48 \\ Decanoic acid ethyl ester & 22.49 & 0.016237 & 2.42 \\
5-Methyl-2-(1-methylethyl)-2-cyclohexen-1-one & 23.68 & 0.000895 & 2.37 \\ N-(3,5-dihydroxyoxyphenyl)acetamide, & 30.19 & 0.000652 & 2.37 \\
2,6-Dimethyllnonane & 5.40 & \(6.76\times 10^{-5}\) & 2.28 \\ Hernticonante & 18.05 & 0.01257 & 2.28 \\
6-Methyl-3-heptanone & 12.33 & 0.00116 & 2.22 \\ Hexadecamethylcyclocatsiloxane & 23.48 & \(1.49\times 10^{-6}\) & 2.21 \\
5-Ethyl-2-decen-4-one & 23.50 & 0.000115 & 2.21 \\ (E)-2-Hexenal & 11.16 & 0.013029 & 2.19 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Cont. pathway that the significant differential metabolites take part in Daohuaxiang 2 vs. Huanghuazhan. (**d**) The KEGG pathway that the significant differential metabolites take part in Daohuaxiang 2 vs. Yanfeng 47. (**e**) The KEGG pathway that the significant differential metabolites take part in Yexiangyoulisi vs. Huanghuazhan. (**f**) The KEGG pathway that the significant differential metabolites take part in Yexiangyoulisi vs. Yanfeng 47.