Table 2. Sources of variation of mean seed mass for 10 genotypes clonally replicated in two contrasting maternal environments.
| Effect |
Seed mass
|
|||
|---|---|---|---|---|
| DF or VarComp | F or χa | P-value | Variance components (%) | |
| Fixed factors | ||||
| Maternal environment (E) | 1, 9 | 84.1 | <0.001 | 17.2 |
| Block (E)a | 15, 69 | 1.7 | 0.064 | 0.8 |
| Cone weightb | 1, 8389 | 228.3 | <0.001 | 58.1 |
| Random factors | ||||
| Mother genotype (G) | 57.2±29.3 | 13.0 | <0.001 | 8.9 |
| G × E | 1.0±4.0 | 0.1 | 0.376 | 0.0 |
| Rametc | 28.5±6.0 | 107.3 | <0.001 | 4.7 |
| Cone (Ramet)a | 19.6±1.9 | 1788.0 | <0.001 | 3.2 |
| Residual | 43.7±0.7 | 7.1 | ||
Abbreviations: DF, degrees of freedom; VarComp, variance components.
DF and F-ratios are shown for fixed effects; VarComp±s.e. and associated χ2 values showing their statistical significance are shown for random factors. Significant (P<0.05) P-values are typed in bold. The variance component (%) column shows the percentage of total variation explained by each factor as obtained from a model in which all categorical factors are considered randomb.
a
Block was nested within seed orchards, and cones were nested within ramets (G × B(E)).
b
The percentage explained by the covariable (cone weight) was determined as the reduction of the total variance when including the covariate in the model.
c
Ramet=G × B(E).