Genetic control of Eucalyptus globulus harvest traits
journal contribution
posted on 2023-05-18, 15:40authored byHamilton, MG, Acuna, M, Wiedemann, JC, Mitchell, R, Pilbeam, DJ, Brown, MW, Bradley PottsBradley Potts
The cost of harvesting short-rotation plantation eucalypts can be in excess of AU$2500·ha−1. Despite this high cost, the extent to which harvesting productivity is affected by tree genetics is not well understood. We address this issue in a study of two 10-year-old genetic field trials of Eucalyptus globulus Labill. in Australia. Standing-tree traits analysed were survival, diameter at breast height, basal area, and stem straightness and forking. Harvest traits analysed were volume, time, and productivity. Genetic group and within-group genetic variation (additive and dominance), stand-level family variation, phenotypic and genetic correlations, and the effects of inbreeding were estimated for these traits. The different scenarios studied showed that plantation harvest productivity was affected by tree genetics to some degree but was mainly affected through positive covariation with stem diameter. Harvest productivity is thus unlikely to have been adversely affected by past selection. Although no significant additive or dominance genetic variation in stem forking or straightness was detected, weak phenotypic correlations were consistent with harvest productivity being higher in straighter trees with no forking. High inbreeding depression was evident for growth and survival; however, in open-pollinated progeny, this resulted in only a slight reduction in harvest productivity (5.5%) compared with out-crossed progeny.
Funding
CRC Forestry Ltd
History
Publication title
Canadian Journal of Forest Research
Volume
45
Issue
6
Pagination
615-624
ISSN
0045-5067
Department/School
School of Natural Sciences
Publisher
Natl Research Council Canada
Place of publication
Research Journals, Montreal Rd, Ottawa, Canada, Ontario, K1A 0R6