Genetic survey of Pinus radiata. 4: Variance structures and heritabilities in juvenile clones

A clonal adjunct to a large Pinus radiata D.Don provenance-progeny trial involved six populations (all the natural populations except Cedros, plus two "land-race " populations from New Zealand) x 30 wind-pollinated progenies (families) x two clones nested within each of two sites x four ramets per clone. The clones were cuttings taken from previously hedged 3-year-old ortets at c. 55 cm height, and came from a subsample of the seedling families used in the main experiment. Genetic parameter estimates from the clones were compared among populations and with estimates from the seedlings. The parameters estimated included broad-sense heritabilities (H2) v. narrow-sense heritabilities (h2), phenotypic variances (addressed largely as coefficients of variation), alternative estimates of genetic variances (total genetic v. additive genetic), and genetic variances between and within families in clonal material. Genetic correlations between performance in seedlings and cuttings of the same families were also studied. Phenotypic variances appeared-similar between the cuttings and parallel geneti