Gains Expected from Clonal Forestry Under Various Selection and Propagation Strategies : Mass Production Technology for Genetically Improved Fast Growing Forest Tree Species

Nangis

Association Foret-Cellulose Paris, IUFRO

1992

S. 328-338

23 Lit. Ang.

Bandaufführung

76078

Three strategies for selection and clonal propagation of trees were compared under a univariate additive genetic model: selection by (i) Phenotype, (ii) family index or (iii) family mean in the progeny test (stage 1 selection), with subsequent selection on clonal mean in the clonal test (stage 2 selection). The differences in genetic gain between strategies based on individual tree selection over family selection were dependent on the heritability and the proportion of clones showing good rooting ability. For the range of heritabilities commonly found in trees, propagation of best mature parents, e.g. from coppice, was more efficient than propagation of clones from best families, e.g. from full sib seedlings. Selection of clones according to a combined index was better than family selection even when heritabilities were low and the proportion of clones with good rooting ability was around 10 to 15%. When even a smaller proportion of potential clones have acceptable propagation characteristics, family propagation with subsequent within family clonal testing appears to be the most appropriate strategy.