<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Genetic gains in breast-height diameter were estimated using deterministic simulation. Simulations of gain from one generation of selection were undertaken in large Main and small Elite breeding populations for a range of heritabilities, with varying numbers of parents, families, seedlings/family, clones/family and ramets/ clone to aid revision of the New Zealand Pinus radiata breeding strategy. Cloned versus seedling populations of equal numbers of plants were simulated, derived from open pollination, polycrossing, and pair crossing. Balanced within-family selection was used for 200, 400 and 800-parent Main breeding populations and among- and within-family selection for 25-parent Elite populations of 25 up to 100 full-sib families. Predicted gains from within-family selection in the Main population were highest from cloned polycross families at all heritabilities and lowest for seedling fullsib families. Gains from cloned populations were higher than seedling equivalents at heritabilities ≤0.5, and their advantage in gain was greatest at lower heritabilities. Elite populations of 25 parents showed similar trends but intensive among- and within-family selection resulted in much higher gains than from the Main, highest from the cloned options. The increase in gain with increased number of families diminished with more than 2-3 times as many families as parents. A new strategy was proposed for P. radiata, based on the simulation results, involving an expanded Main breeding population of open-pollinated (OP) seedling families, together with pair-cross family seedlots already available, supported by parentage reconstruction using DNA markers. Forwards selection in small cloned Elite populations was proposed as the main source of seed orchard clones.</p></abstract>

Genetic gains in breast-height diameter were estimated using deterministic simulation. Simulations of gain from one generation of selection were undertaken in large Main and small Elite breeding populations for a range of heritabilities, with varying numbers of parents, families, seedlings/family, clones/family and ramets/ clone to aid revision of the New Zealand Pinus radiata breeding strategy. Cloned versus seedling populations of equal numbers of plants were simulated, derived from open pollination, polycrossing, and pair crossing. Balanced within-family selection was used for 200, 400 and 800-parent Main breeding populations and among- and within-family selection for 25-parent Elite populations of 25 up to 100 full-sib families. Predicted gains from within-family selection in the Main population were highest from cloned polycross families at all heritabilities and lowest for seedling fullsib families. Gains from cloned populations were higher than seedling equivalents at heritabilities ≤0.5, and their advantage in gain was greatest at lower heritabilities. Elite populations of 25 parents showed similar trends but intensive among- and within-family selection resulted in much higher gains than from the Main, highest from the cloned options. The increase in gain with increased number of families diminished with more than 2-3 times as many families as parents. A new strategy was proposed for P. radiata, based on the simulation results, involving an expanded Main breeding population of open-pollinated (OP) seedling families, together with pair-cross family seedlots already available, supported by parentage reconstruction using DNA markers. Forwards selection in small cloned Elite populations was proposed as the main source of seed orchard clones.

Deterministic Simulation of Gains for Seedling and Cloned Main and Elite Breeding Populations of Pinus radiata and Implications for Strategy

Silvae Genetica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Genetic gains in breast-height diameter were estimated using deterministic simulation. Simulations of gain from one generation of selection were undertaken in...

Deterministic Simulation of Gains for Seedling and Cloned Main and Elite Breeding Populations of Pinus radiata and Implications for Strategy

Published Online: Oct 14, 2017

Page range: 259 - 270

Received: Aug 11, 2006

DOI: https://doi.org/10.1515/sg-2007-0037

Keywords
breeding populations, deterministic simulation, genetic gain, cloning, open-pollination, controlled pollination, backwards selection, forwards selection, seed orchard, Pinus radiata

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Deterministic Simulation of Gains for Seedling and Cloned Main and Elite Breeding Populations of Pinus radiata and Implications for Strategy

Published Online: Oct 14, 2017

Page range: 259 - 270

Received: Aug 11, 2006

DOI: https://doi.org/10.1515/sg-2007-0037

Keywordsbreeding populations, deterministic simulation, genetic gain, cloning, open-pollination, controlled pollination, backwards selection, forwards selection, seed orchard, Pinus radiata

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
breeding populations, deterministic simulation, genetic gain, cloning, open-pollination, controlled pollination, backwards selection, forwards selection, seed orchard, Pinus radiata