Table 2.

Effects of environmental variables on the emission of VOCs selected through SIMPER for both summer and winter.

Compound	Environmental variables
	Herbivory		Temperature		Nitrogen		SWC
Summer 2017	F	P	F	P	F	P	F	P
(Z)-3-hexenol	5.140	0.042	10.102	0.008	0.040	0.840	0.410	0.487
(Z)-3-hexenyl acetate	3.810	0.076	1.360	0.259	5.540	0.038	0.020	0.898
β-pinene	0.130	0.730	1.608	0.231	7.892	0.014	0.209	0.575
Cadinadiene-1,4	2.923	0.089	4.333	0.041	0.737	0.410	0.007	0.915
Copaene	5.118	0.043	2.051	0.174	2.678	0.110	0.084	0.768
Germacrene D	11.302	0.005	14.951	0.008	1.449	0.247	0.0015	0.978
Humulene	3.526	0.061	5.648	0.026	0.498	0.487	0.389	0.520
Isoledene	0.509	0.431	6.160	0.014	0.383	0.552	0.007	0.924
α-cubebene	5.970	0.023	2.942	0.116	0.510	0.479	0.062	0.823
α-selinene	0.186	0.645	4.336	0.048	4.678	0.041	0.405	0.470
β-elemene	15.174	0.006	4.410	0.062	0.016	0.904	0.024	0.862
β-selinene	0.970	0.291	4.553	0.042	3.213	0.100	0.007	0.920
2-Heptanone	1.231	0.178	1.772	0.228	8.375	0.014	0.003	0.934
2-methyl-1-butanol acetate	22.426	0.002	6.321	0.024	0.572	0.469	1.150	0.262
3-methyl-1-butanol acetate	23.687	0.001	6.605	0.015	0.444	0.510	0.827	0.405
Winter 2018
Aromadendrene	< 0.001	0.987	8.997	0.011	15.823	0.003	3.553	0.062
Cadinadiene-1,4	4.945	0.045	1.971	0.173	3.871	0.060	5.951	0.036
Calamenene	2.995	0.115	3.764	0.077	0.354	0.557	4.594	0.045
Isoledene	6.019	0.036	1.951	0.198	0.011	0.917	0.348	0.552
Alloaromadendrene	0.747	0.369	0.055	0.816	1.852	0.171	6.498	0.025
α-gurjunene	3.386	0.087	1.862	0.181	4.788	0.045	7.819	0.021
α-selinene	0.764	0.395	2.021	0.165	4.254	0.048	4.167	0.053
β-chamigrene	3.412	0.080	8.421	0.011	1.880	0.207	2.356	0.156
β-elemene	0.033	0.859	7.424	0.015	0.370	0.547	0.667	0.436
β-selinene	2.355	0.127	9.163	0.010	1.236	0.262	2.747	0.118

Pseudo-F (F) and P values (P) calculated using PERMANOVA based on Euclidean distances. Significant P values (P < 0.050) are highlighted in bold.

SWC soil water content.