Estimating Genetic Parameters for Wood Density of Scots Pine (Pinus sylvestris L.)

• Published in: Silvae Genetica
• Main Authors: Fries, Anders, Ericsson, Tore
• Format: Article in Journal/Newspaper
• Language: English
• Published: Walter de Gruyter GmbH 2006
• Subjects: North Sweden
• Online Access: http://dx.doi.org/10.1515/sg-2006-0013; http://content.sciendo.com/view/journals/sg/55/1-6/article-p84.xml; https://www.sciendo.com/article/10.1515/sg-2006-0013

Abstract Wood density was analysed and annual ring width was measured on increment cores from 1400 trees in a 30-year-old full-sib progeny test of Scots pine (Pinus sylvestris L.) in north Sweden. Genetic parameters for wood density were analysed separately for ten outer annual rings, and for simple averages of the five most recent years. The evaluation included genetic correlations with height and stem diameter. Heritabilities of density estimated separately for each annual ring was 0.14-0.26 without any age trend, and jointly for the ten or five latest rings 0.30-0.33; for height growth it was 0.30-0.42 and for stem diameter 0.11-0.13. Additive genetic correlations with height and stem diameter were negative with the simplest statistical model (ȓ A = -0.425 and 0.511, respectively) but vanished or diminished when ring width was added as covariate. Density breeding values calculated for the parent trees for each of ten annual rings separately varied considerably between parent trees and between years, tending to increase with increasing age, with a substantial increase between the ages 14 to 16 years from the pith. This age fits well with literature data on the change from juvenile to mature wood. The genetic correlation for wood density between rings from different years was high: ȓ A = 0.8 ten years apart, increasing to 1.0 for neighbouring rings. The high genetic correlations for wood density between the innermost and outermost annual rings indicate possible strong covariation between juvenile and/or transition wood and mature wood. The annual variation in wood density in relation to genetic regulation, phenology, environmental conditions, and development from juvenile to mature age is discussed.