<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Eighty six full-sib Corymbia F1 hybrid families (crosses between C. torelliana and four spotted gum taxa: C. citriodora subsp. variegata, C. citriodora subsp. citriodora, C. henryi and C. maculata), were planted in six trials across six disparate sites in south-eastern Queensland to evaluate their productivity and determine their potential utility for plantation forestry. In each trial, the best-growing 20% of hybrid families grew significantly faster (P = 0.05) than open-pollinated seedlots of the parent species Corymbia citriodora subsp. variegata, ranging from 107% to 181% and 127% to 287% of the height and diameter respectively. Relative performance of hybrid families growing on more than one site displayed consistency in ranking for growth across sites and analysis showed low genotype-by-environment interaction. Heritability estimates based on female and male parents across two sites at age six years for height and diameter at breast height, were high (0.62 ± 0.28 to 0.64 ± 0.35 and 0.31 ± 0.21 to 0.69 ± 0.37 respectively), and low to moderate (0.03 ± 0.04 to 0.33 ± 0.22) for stem straightness, branch size, incidence of ramicorns, and frost and disease resistance traits at ages one to three years. The proportion of dominance variance for height and diameter had reduced to zero by age six years. Based on these promising results, further breeding and pilot-scale family forestry and clonal forestry deployment is being undertaken. These results have also provided insights regarding the choice of a future hybrid breeding strategy.</p></abstract>

Eighty six full-sib Corymbia F1 hybrid families (crosses between C. torelliana and four spotted gum taxa: C. citriodora subsp. variegata, C. citriodora subsp. citriodora, C. henryi and C. maculata), were planted in six trials across six disparate sites in south-eastern Queensland to evaluate their productivity and determine their potential utility for plantation forestry. In each trial, the best-growing 20% of hybrid families grew significantly faster (P = 0.05) than open-pollinated seedlots of the parent species Corymbia citriodora subsp. variegata, ranging from 107% to 181% and 127% to 287% of the height and diameter respectively. Relative performance of hybrid families growing on more than one site displayed consistency in ranking for growth across sites and analysis showed low genotype-by-environment interaction. Heritability estimates based on female and male parents across two sites at age six years for height and diameter at breast height, were high (0.62 ± 0.28 to 0.64 ± 0.35 and 0.31 ± 0.21 to 0.69 ± 0.37 respectively), and low to moderate (0.03 ± 0.04 to 0.33 ± 0.22) for stem straightness, branch size, incidence of ramicorns, and frost and disease resistance traits at ages one to three years. The proportion of dominance variance for height and diameter had reduced to zero by age six years. Based on these promising results, further breeding and pilot-scale family forestry and clonal forestry deployment is being undertaken. These results have also provided insights regarding the choice of a future hybrid breeding strategy.

Comparative Performance of Corymbia Hybrids and Parental Species in Subtropical Queensland and Implications for Breeding and Deployment

Silvae Genetica

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

Eighty six full-sib Corymbia F1 hybrid families (crosses between C. torelliana and four spotted gum taxa: C. citriodora subsp. variegata, C. citriodora subsp....

Comparative Performance of Corymbia Hybrids and Parental Species in Subtropical Queensland and Implications for Breeding and Deployment

Published Online: Oct 19, 2017

Page range: 205 - 212

Received: Mar 25, 2008

DOI: https://doi.org/10.1515/sg-2009-0026

Keywords
Spotted gums, Hybrid, Corymbia, Eucalypt, Quambalaria, Breeding strategy, Deployment, Heritability, Genetic parameters.

© 2017

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

Comparative Performance of Corymbia Hybrids and Parental Species in Subtropical Queensland and Implications for Breeding and Deployment

Published Online: Oct 19, 2017

Page range: 205 - 212

Received: Mar 25, 2008

DOI: https://doi.org/10.1515/sg-2009-0026

KeywordsSpotted gums, Hybrid, Corymbia, Eucalypt, Quambalaria, Breeding strategy, Deployment, Heritability, Genetic parameters.

© 2017

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

Keywords
Spotted gums, Hybrid, Corymbia, Eucalypt, Quambalaria, Breeding strategy, Deployment, Heritability, Genetic parameters.