The natural durability of wooden structures subjected to decay has become more important along with increasing concern about the ecological impacts of wood preservation chemicals. The fact that wood is highly variable in its characteristics offers a real challenge for its optimal use in various applications.
The possibility of increasing the quality and quantity of Scots pine heartwood timber by means of forest tree breeding was studied by estimating phenotypic and genetic parameters for stem diameter, the amount of heartwood and the concentration of total phenolics in the heartwood. The concentration of total phenolics has proven to be a good predictor of the resistance to decay of Scots pine heartwood, which can be regarded as an important wood quality characteristic. The estimated genetic parameters comprised heritability, additive genetic coefficient of variation, and genetic correlation. The purpose was to describe the distribution of the studied characteristics and to evaluate the outcome of selection.
The phenotypic variation in all the traits was wide. In the concentration of total phenolics, a large part of the variation was attributed to genetic differences among the families. For the variation in the stem diameter and the amount of heartwood the environmental effect was more pronounced. The phenotypic and genetic correlations between the studied characteristics varied between –0.24 – 0.04 and –0.26 – 0.04, respectively.
In a breeding program, target traits may be improved by combining them into a single selection index, or by selecting for each trait separately.
Based on this preliminary study on a single progeny test, we conclude that it is possible to select for trees with a larger proportion of heartwood and better decay resistance without a loss in volume growth.
Keywords: Heartwood, durability, quantity, growth, forest tree breeding
Authors
Harju A.
Finnish Forest Research Institute, Punkaharju Research Unit, Punkaharju, Finland
Venäläinen M.
Finnish Forest Research Institute, Punkaharju Research Unit, Punkaharju, Finland
Haapanen M.
Finnish Forest Research Institute, Vantaa Research Unit, Vantaa, Finland
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