## 2 Results and Discussion
### Discrimination of Different Flower Stages by Electronic Nose
Figure 2: Two-dimensional (2D) DFA plots of flower from different stages by electronic nose. **(I)** bud stage; **(II)** display-petal stage; **(III)** initial-flowering stage; **(IV)** full-flowering stage; **(V)** end-flowering stage; **(VI)** wilted-flower stage; and **(VII)** dried flower stage. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Peak** & \(RT\)\({}^{*}\) & \(LRf\)\({}^{*}\) & **Compounds** & \multicolumn{6}{c}{**Relative Content (\%) \& SD**} \\ \cline{4-11}  & & & **1** & **1** & **1** & **1** & **1** & **1** & **1** & **1** & **1** \\ \hline
**Acids** & & & & & & & & & & \\ \hline
1 & 9.001 & 1020 & (S)-\(\alpha\)-methoxybenzene acetic acid & - & - & 6.631 \(\pm\) 0.601 & 11.711 \(\pm\) 0.571 & - & - & - \\ \hline
**Esters** & & & & & & & & & \\ \hline
2 & 8.460 & 1002 & (Z)-3-hexen-1-ol acetate & - & - & - & 0.070 \(\pm\) 0.012 & - & - & - \\ \hline
3 & 8.675 & 1009 & hexyl acetate & - & - & - & 0.026 \(\pm\) 0.001 & - & - & - \\
4 & 8.746 & 1011 & (E)-2-hexen-1-ol acetate & - & - & - & 0.044 \(\pm\) 0.019 & - & - & - \\
5 & 11.219 & 1094 & methyl benzene & - & 0.067 \(\pm\) 0.011 & 0.308 \(\pm\) 0.002 & 2.605 \(\pm\) 0.673 & 5.604 \(\pm\) 0.129 & - & - \\
6 & 13.240 & 1162 & benzyl acetate & - & - & - & 0.149 \(\pm\) 0.001 & 0.126 \(\pm\) 0.030 & - & - \\
7 & 13.495 & 1170 & benzoic acid, ethyl ester & - & - & - & 0.314 \(\pm\) 0.260 & 0.226 \(\pm\) 0.085 & - & - \\
8 & 15.481 & 1238 & 1 inaly acetate & - & - & - & - & 0.139 \(\pm\) 0.380 & - \\
9 & 17.191 & 1298 & methyl2-methoxybenzoate & - & - & 0.050 \(\pm\) 0.012 & - & - & - \\
10 & 18.810 & 1358 & 1 vandually acetate & - & - & - & 0.079 \(\pm\) 0.016 & 0.063 \(\pm\) 0.014 & - & - \\
11 & 19.258 & 1374 & 1,2-ethanediol 1-benzoate & - & - & - & 0.304 \(\pm\) 0.239 & - & - & - \\
12 & 19.369 & 1378 & nearly acetate & - & - & 7.882 \(\pm\) 0.227 & 11.740 \(\pm\) 0.718 & - & - & - \\
13 & 19.380 & 1379 & general acetate & - & 0.075 \(\pm\) 0.051 & - & - & 13.777 \(\pm\) 1.311 & - & - \\
14 & 21.092 & 1445 & cinnamy acetate & - & - & - & 0.073 \(\pm\) 0.008 & 0.161 \(\pm\) 0.015 & - & - \\
15 & 24.231 & 1572 & (Z)-3-hexenyl benzoate & 0.123 \(\pm\) 0.013 & - & 0.115 \(\pm\) 0.042 & - & 0.118 \(\pm\) 0.014 & 0.144 \(\pm\) 0.001 & - \\
16 & 28.647 & 1768 & benzyl benzoate & 1.638 \(\pm\) 0.054 & 2.498 \(\pm\) 0.004 & 2.239 \(\pm\) 0.802 & 2.146 \(\pm\) 1.489 & 6.150 \(\pm\) 0.896 & 2.893 \(\pm\) 0.817 & 0.668 \(\pm\) 0.226 \\
17 & 30.801 & 1871 & benzyl salicylate & - & - & - & 0.066 \(\pm\) 0.014 & 0.113 \(\pm\) 0.030 & - & - \\
18 & 32.626 & 1963 & general benzoate & - & - & - & - & 0.044 \(\pm\) 0.018 & - & - \\ \hline
**Acabolids** & & & & & & & & & \\ \hline
19 & 4.919 & 854 & 3-hexen-1-ol & - & 0.086 \(\pm\) 0.025 & - & - & - & - \\
20 & 9.349 & 1031 & 0-ol-olubenol & - & - & - & 0.071 \(\pm\) 0.048 & 0.086 \(\pm\) 0.033 & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Volatile compounds identified in seven different stages of _C. odorata_ flower development using HS-SPME-GC-MS. (I) bud stage; (II) display-petal stage; (III) initial-flowering stage; (V) full-flowering stage; (V) end-flowering stage; (VI) wited-flower stage; and (VII) dried flower stage.