Table 4. Summary of the full mixed models for the evaluation of Hylobius abietis and Thaumetopoea pityocampa damage through in vitro feeding tests.

Fixed effects	Damage by H. abietis			Damage by T. pityocampa
	df	F	P-value	df	F	P-value
Induction treatment	1, 3	13.6	0.035	1, 3	12.8	0.038
Insect weight	1, 193	28.3	<0.001	1, 73	4.1	0.048
Random effects	Varcomp	χ2	P-value	Varcomp	χ2	P-value
Family (in control)	0±0	0.0	0.500	0.032±0.016	14.9	0.000
Family (in induced)	0±0	0.0	0.500	0.008±0.008	2.5	0.057
Correlation control–induced	1±0	0.0	0.500	0.500±0.45	1.0	0.159
Residual (control)	0.15±0.02			0.032±0.008
Residual (induced)	0.21±0.03			0.043±0.01

Abbreviations: df, degree of freedom; MJ, methyl jasmonate.

The experiment was conducted with several P. radiata open-pollinated families (34 for H. abietis test and 14 for T. pityocampa test) in constitutive and MJ-treated conditions 15 days after MJ application. The treatment of defence induction (T) is a fixed effect, and the F values and corresponding df are shown. Insect weight was included as covariate. The full mixed model assumed a completely unstructured (co)variance structure for the family random factor, and heterogeneous residual variances across treatments. Variance component estimates (±s.e.) and the likelihood ratio tests (χ²) testing whether they are significantly greater than zero are shown. Significant P-values (P<0.05) are typed in bold.