Skip to main content

Table 2 Across-trial estimates of variances, narrow-sense individual heritability, narrow-sense family heritability, type B genetic correlation, relative expected genetic gain by selecting the top 1%, standard error (between parentheses), and relative magnitudea [between brackets, %] for wood density traits estimated at year 24 from progeny trials in the mixed and boreal forests

From: Rapid assessment of wood traits for large-scale breeding selection in Picea mariana [Mill.] B.S.P.

Vegetation subzone Mixed forest Boreal forest
Parameter WD vol WD pil WD res WD vol WD pil WD res
\( {\widehat{\sigma}}_F^2 \) 78.45b 0.28b 1.37b 88.07b 0.16b 1.11
(24.45) (0.11) (0.57) (27.55) (0.06) (0.69)
[6.9] [5.8] [5.6] [8.0] [5.3] [3.6]
\( {\widehat{\sigma}}_{S\ast F}^2 \) 0 0.07 0.51 3.93 0 0.38
  (0.10) (0.53) (19.87)   (0.77)
[0] [1.5] [2.1] [0.4] [0] [1.2]
\( {\widehat{\sigma}}_{\varepsilon}^2 \) 1062.20b 4.42b 22.43b 1008.00b 2.84b 29.44b
(45.31) (0.19) (0.98) (43.99) (0.12) (1.44)
[93.1] [92.7] [92.3] [91.6] [94.7] [95.2]
\( {\widehat{h}}_{ind}^2 \) 0.28 0.23 0.23 0.32 0.21 0.14
(0.08) (0.09) (0.09) (0.09) (0.07) (0.09)
\( {\widehat{h}}_{\; fam}^2 \) 0.59 0.52 0.49 0.62 0.52 0.34
(0.08) (0.13) (0.13) (0.10) (0.09) (0.16)
\( {\widehat{r}}_B \) 1b 0.80b 0.73b 0.96b 1b 0.74
(0) (0.26) (0.25) (0.21) (0) (0.46)
\( {\widehat{G}}_{1\%} \) 5.32 5.50 13.81 5.70 4.65 8.37
  1. \( {\widehat{\sigma}}_F^2 \) Among-family variance component estimate, \( {\widehat{\sigma}}_{S\ast F}^2 \) site × family interaction variance component estimate, \( {\widehat{\sigma}}_{\varepsilon}^2 \) residual variance estimate due to among-plot variation, \( {\widehat{h}}_{ind}^2 \) unbiased individual-tree narrow-sense heritability, \( {\widehat{h}}_{\; fam}^2 \) unbiased half-sib narrow-sense heritability, \( {\widehat{r}}_B \) type B genetic correlation, \( {\widehat{G}}_{1\%} \) relative expected genetic gain by selecting the top 1% expressed as a percentage, WD vol volumetric wood density, WD pil Pilodyn wood density, WD res Resistograph® wood density
  2. aPercentage of each estimated variance component to total (phenotypic) variance \( \left({\widehat{\sigma}}_p^2={\widehat{\sigma}}_F^2+{\widehat{\sigma}}_{S\ast F}^2+{\widehat{\sigma}}_{\varepsilon}^2\right) \)
  3. bSignificantly different from 0 (for \( {\widehat{r}}_B \)) or significantly positive (for variance estimates) at the 5% significance level.