Research article - Peer-reviewed, 2017
Modeling early height growth in trials of genetically improved Norway spruce and Scots pine in Southern Sweden
Egback, Samuel; Nilsson, Urban; Nystrom, Kenneth; Hogberg, Karl-Anders; Fahlvik, NilsAbstract
Genetically improved Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) are used extensively in operational Swedish forestry plantations to increase production. Depending on the genetic status of the plant material, the current estimated genetic gain in growth is in the range 10-20% for these species and this is expected to increase further in the near future. However, growth models derived solely from data relating to genetically improved material in Sweden are still lacking. In this study we investigated whether an individual tree growth model based on data from unimproved material could be used to predict the height increment in young trials of genetically improved Norway spruce and Scots pine. Data from 11 genetic experiments with large genetic variation, ranging from offspring of plus-trees selected in the late 1940s to highly improved clonal materials selected from well performing provenances were used. The data set included initial heights at the age of 7-15 years and 5-year increments for almost 2000 genetic entries and more than 20 000 trees. The evaluation indicated that the model based on unimproved trees predicted height development relatively well for genetically improved Norway spruce and there was no need to incorporate a genetic component. However, for Scots pine, the model needed to be modified. A genetic component was developed based on the genetic difference recorded within each trial, using mixed linear models and methods from quantitative genetics. By incorporating the genetic component, the prediction errors were significantly reduced for Scots pine. This study provides the first step to incorporate genetic gains into Swedish growth models and forest management planning systems.Keywords
individual tree growth model; genetic component; genetic multiplier; unimproved material; improved material; Picea abies; Pinus sylvestrisPublished in
Silva Fennica2017, volume: 51, number: 3, article number: 5662
Authors' information
Egbäck, Samuel
Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre
Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre
Swedish University of Agricultural Sciences, Department of Forest Resource Management
Högberg, Karl-Anders
Forestry Research Institute of Sweden, Skogforsk
Fahlvik, Nils
Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre
UKÄ Subject classification
Agricultural Science
Publication Identifiers
DOI: https://doi.org/10.14214/sf.5662
URI (permanent link to this page)
https://res.slu.se/id/publ/91700