Estimation of Genetic-Gain Multipliers for Modeling Douglas-Fir Height and Diameter Growth

$29.50 plus tax (Refund Policy)

Buy Article:


Methods were developed to calculate genetic-gain multipliers for use in individual-tree models that predict periodic height and diameter growth of coast Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) in the Pacific Northwest. Genetic-gain multipliers are used in growth models that are typically based on extensive measurements of unimproved or “woods-run” stands, to adjust for the increased growth of stands generated from improved seedlots. First-generation progeny test data from multiple breeding zones in the Northwest Tree Improvement Cooperative were used. Data sets included initial heights and diameters and 5-year growth increments for 10- and 15-year-old trees that were identified by open-pollinated families. Nonlinear mixed-effect models were initially developed to predict the average growth of trees in all families, which, taken together, represented woods-run populations. Phenotypic differences in growth rates were then calculated at the family level. Differences among families in height and diameter growth rates were examined using methods from quantitative genetics and raw phenotypic values. Because gain in total height and diameter at age 10 years is currently the most widely available genetic information for improved Douglas-fir, equations were developed to predict genetic-gain multipliers from family breeding values for these traits. A verification procedure illustrated how incorporating multipliers in growth projections could reduce the mean-square error of predicted growth of selected families.

Keywords: Pacific Northwest; growth models; progeny tests; tree improvement

Document Type: Research Article

Publication date: December 1, 2008

More about this publication?
  • Membership Information
  • ingentaconnect is not responsible for the content or availability of external websites
Related content



Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more