Table 3.

Significance tests of the family effect and corresponding narrow sense heritability estimates for the constitutive (control plants) and induced (MeJa treated plants) concentration of individual volatile terpenes in the needles of 17 P. pinaster open-pollinated families

	Constitutive mode			MeJa-induced mode
	χ2	P value	${\text{h}}_i^2$	χ2	P value	${\text{h}}_i^2$
Monoterpenes
α-Pinene	12.7	0.000	0.87	5.2	0.011	0.45
Camphene	0.6	0.213		1.3	0.126
β-Pinene	16.3	0.000	1.00	1.9	0.085
β-Myrcene	0.0	0.500		0.0	0.500
α-Phellandrene	1.8	0.093		0.1	0.407
Δ-3-Carene	9.1	0.001	0.64	6.6	0.005	0.60
α-Terpinene	0.7	0.199		0.0	0.478
Limonene	11.8	0.000	0.83	2.6	0.053
(±)-3-Carene	2.2	0.067		3.1	0.038	0.39
α-Terpinolene	8.2	0.002	0.67	1.0	0.154
Linalyl acetate	4.7	0.015	0.49	0.8	0.180
Bornyl acetate	7.5	0.003	0.64	0.2	0.349
Total monoterpenes	17.8	0.000	1.06	3.2	0.037	0.38
Sesquiterpenes
α-Copaene	12.8	0.000	0.87	0.0	0.500
Jupinene	26.3	0.000	1.30	16.7	0.000	1.02
Trans-Caryophyllene	14.7	0.000	0.94	1.1	0.145
α-Humulene	14.9	0.000	0.95	0.4	0.276
α-Amorphene	0.0	0.500		0.0	0.500
Germacrene D	6.1	0.007	0.56	0.0	0.500
α-Muurolene	2.1	0.074		7.8	0.003	0.65
Δ-Cadinene	0.1	0.396		0.2	0.337
Caryophyllene oxide	0.0	0.500		0.0	0.500
Geranyl acetate	0.0	0.500		0.2	0.326
Farnesyl acetate	0.0	0.500		0.7	0.194
Unknown	0.0	0.447		0.0	0.500
Farnesyl acetone	0.0	0.500		0.0	0.500
α-Bisabolene	5.6	0.009	0.54	0.0	0.500
Total sesquiterpenes	12.2	0.000	0.83	0.1	0.385
Overall volatile terpenes	19.3	0.000	1.11	3.1	0.039	0.37

Most of the more abundant terpenes showed high heritabilities. Heritability was calculated only when family effect was significant as the ratio of additive genetic variance (σ_A²=4·σ_F², where σ_F² is the family variance) to total phenotypic variance. Bold values are significant at α <0.05.