Selection of Corymbia citriodora for pulp productivity

  • JT Brawner
  • R Meder
  • M Dieters
  • DJ Lee

Abstract

Evaluation of a series of spotted gum (Corymbia citirodora) progeny  trials, established in the subtropical region of Queensland, Australia, was undertaken to provide information for the development of advanced-generation  breeding populations suitable for pulp production. Measurements of growth at two ages were combined with assessments of wood density and pulp yield from a selected sample of provenances to provide comparisons between provenances, to generate genetic parameter estimates and to predict genetic gain potential. Although growth at this age was moderate relative to other eucalypts, the near-infrared predictions of average wood density of 756 kg m3 and pulp yield of 55% indicate the species has considerable potential as a pulpwood crop. A pulp productivity breeding objective was used to identify production populations using a range of selection trait weightings to determine potential genetic gain for pulp productivity. Genetic parameters indicated (1) levels of genetic control were moderate for all traits and higher for wood property traits, (2) genetic improvements could be achieved by selection among and within provenances with greater levels of improvement available from selection within populations, (3) genotype by environment interactions were negligible, (4) genetic correlations between traits were favourable, and (5) selection of volume production alone would maximise improvements in pulp productivity.

Keywords: Corymbia citriodora subsp. variegata, genetic parameters, index selection, subtropics, wood quality

Southern Forests 2012, 74(2): 121–131

Author Biographies

JT Brawner
CSIRO – Plant Industry, 306 Carmody Road, St Lucia, QLD 4067, Australia; School of Land, Crop and Food Sciences, University of Queensland, St Lucia, QLD 4072, Australia
R Meder
CSIRO – Plant Industry, 306 Carmody Road, St Lucia, QLD 4067, Australia
M Dieters
School of Land, Crop and Food Sciences, University of Queensland, St Lucia, QLD 4072, Australia
DJ Lee
University of the Sunshine Coast, Maroochydore, QLD 4558, Australia; Department of Employment, Economic Development and Innovation, PO Box 395, Gympie, QLD 4570, Australia
Section
Articles

Journal Identifiers


eISSN: 2070-2639
print ISSN: 2070-2620