## 3 Results
Maximum distance to centroid was found for cluster 1 of 8.73 between two clusters, indicating the similarity of chemical profiles among the B1, B3 and B4 samples (Table 7). Cluster 2 showed maximum distances to centroid was zero, indicating it was closed to cluster 1. Compounds \(\alpha\)-zingiberene, _ar_-curcumene and \(\beta\)-caryophyllene showed a strong impact on cluster 1 and 2. This finding was also in accordance with the experimental data detected by GC-MS (Table 1). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Variables**} & \multicolumn{3}{c}{**Contribution of the Variables (\%)**} & \multicolumn{3}{c}{**Squared Cosines of the Variables \({}^{*}\)**} \\ \cline{2-7}  & **F1** & **F2** & **F3** & **F1** & **F2** & **F3** \\ \hline \(\alpha\)-thujene & 2.737 & 0.580 & 10.088 & 0.431 & 0.041 & 0.528 \\ \(\alpha\)-pinene & 2.540 & 0.766 & 10.428 & 0.400 & 0.054 & 0.546 \\ sabinene & 2.087 & 1.079 & 11.372 & 0.329 & 0.076 & 0.596 \\ (\(E\))-3-hexenyl acetate & 0.000 & 5.361 & 11.907 & 0.000 & 0.376 & 0.624 \\ (\(E\))-\(\beta\)-ocimene & 5.340 & 2.221 & 0.066 & 0.841 & 0.156 & 0.003 \\ \(\gamma\)-terpinene & 1.412 & 1.709 & 12.555 & 0.222 & 0.120 & 0.658 \\ _cis_-linalo oxide & 4.916 & 3.121 & 0.136 & 0.774 & 0.219 & 0.007 \\ _trans_-linalo oxide & 4.916 & 3.121 & 0.136 & 0.774 & 0.219 & 0.007 \\ _trans_-linalool oxide & 4.944 & 3.072 & 0.114 & 0.778 & 0.216 & 0.006 \\ cyclosativene & 5.852 & 0.104 & 1.363 & 0.921 & 0.007 & 0.071 \\ \(\alpha\)-ylangene & 0.117 & 13.896 & 0.121 & 0.018 & 0.975 & 0.006 \\ \(\alpha\)-copaene & 6.123 & 0.499 & 0.019 & 0.964 & 0.035 & 0.001 \\ \(\gamma\)-epi-sesquithujene & 1.313 & 4.287 & 9.402 & 0.207 & 0.301 & 0.493 \\ \(\beta\)-caryophyllene & 6.146 & 0.300 & 0.216 & 0.968 & 0.021 & 0.011 \\ \(\beta\)-corene & 3.488 & 0.880 & 7.428 & 0.549 & 0.062 & 0.389 \\ _trans_-\(\alpha\)-bergamotene & 5.854 & 0.160 & 1.281 & 0.922 & 0.011 & 0.067 \\ \(\alpha\)-humulene & 6.027 & 0.000 & 0.976 & 0.949 & 0.000 & 0.051 \\ (\(E\))-\(\beta\)-farnesene & 2.140 & 9.446 & 0.005 & 0.337 & 0.663 & 0.000 \\ (\(trans\)-cadina-1(6),\(A\)-diene & 3.593 & 5.625 & 0.756 & 0.566 & 0.395 & 0.040 \\ \(\gamma\)-muurolene & 0.000 & 14.161 & 0.118 & 0.000 & 0.994 & 0.006 \\ _ar_-curcumene & 5.230 & 0.259 & 3.023 & 0.823 & 0.018 & 0.158 \\ \(\alpha\)-zingiberene & 6.186 & 0.013 & 0.482 & 0.974 & 0.001 & 0.025 \\ \(\alpha\)-muurolene & 3.120 & 2.628 & 6.191 & 0.491 & 0.184 & 0.324 \\ (\(E\),\(E\))-\(\alpha\)-farnesene & 1.071 & 11.638 & 0.281 & 0.169 & 0.817 & 0.015 \\ \(\beta\)-curcumene & 2.018 & 1.685 & 10.766 & 0.318 & 0.118 & 0.564 \\ \(\beta\)-sesquiphellandrene & 5.343 & 1.860 & 0.539 & 0.841 & 0.131 & 0.028 \\ \(\delta\)-cadinene & 2.571 & 8.410 & 0.096 & 0.405 & 0.590 & 0.005 \\ Total & 100.000 & 100.000 & 100.000 & 15.743 & 7.018 & 5.238 \\ \hline \hline \end{tabular}  
* Values in bold correspond for each variable to the factor for which the squared cosine is the largest.  
\end{table} 
Table 6: Relative contributions and squared cosines of each principal component to samples B1 to B4. LEM Behavioral Responses to Field-Collected (Non-Infested) Lychee Tissues and Single Volatile Compounds  
In almost all cases, when given a choice between two field-collected (non-infested) lychee tissues (control groups), there was no significant difference in the number of LEM that reached both sources. Except when presented with a choice between leaf shoot vs. leaf shoot there was a slightly significant difference (\(p=0.04\)) towards one of the sides (Figure S2). For the other groups tested, fruit vs. fruit (\(p=0.1\)), leaf vs. leaf (\(p=0.1\)) and bud vs. bud (\(p=0.31\)) there was no difference between choices made by LEM. When different plant tissues were offered, LEM showed a preference for leaf shoot over buds (\(p=0.04\), Figure 5). No clear choice was observed for the other treatments, leaf vs. fruit (\(p=0.61\)), leaf vs. bud (\(p=0.12\)), leaf vs. leaf shoot (\(p=0.31\)), fruit vs. bud (\(p=0.31\)) and fruit vs. leaf shoot (\(p=0.1\)).