Genetic variation of wood quality traits and relationships with growth in Picea abies

Abstract

Genetic parameters were estimated for wood density and spiral grain in two long-term field trials with families of Picea abies (L.) Karst., and for microfibril angle (MfA) and model-predicted wood stiffness (MOE_est) at one of the sites. The trials were located at 600–720 m altitude in Norway and the progenies, which were a sample of 13 half-sib families from plus-trees in a breeding population, were 33 years old from seed when measured. Significant genetic variation (p<0.05) was found for all wood quality traits. The narrow-sense heritability was estimated to be 0.50 for density (across two sites), 0.38 for MfA, 0.29 for MOE_est and 0.37 for spiral grain (across two sites). No significant genotype by environment interactions were found for density or spiral grain (p>0.05). Genetic relationships between ring width and wood quality traits were negative for density and MOE_est, and positive for MfA. Site index and competition had major effects on wood density and predicted MOE_est but not on MfA and spiral grain.

Keywords:

• Genetic correlations
• genetic variation
• growth traits
• Norway spruce
• tree breeding
• wood quality

Acknowledgements

The research was funded by Norwegian Forest and Landscape Institute. Grateful thanks to the many who made valuable contributions on various matters such as fieldwork, feedback on the manuscript and assistance on the methods: Christian Kierulf, Geir Østreng, Øystein Johnsen and Ari Hietala (Norwegian Forest and Landscape Institute); Gunnar Haug and Ragnar Johnskås (Norwegian Forest Seed Center); Sven-Olof Lundqvist, Åke Hansson and Lars Olsson (STFI-Packforsk); Knut Sigmund Dalen (Norwegian University of Life Sciences); Gunnar Jansson and Björn Hannrup (Forestry Research Institute of Sweden); Daniel Gräns (North Carolina State University); and Owe Lindgren (Luleå University of Technology).