Résumé :
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On the background of the present declining situation for Norway spruce in Denmark, new developments of breeding methods and adjustments of breeding objectives, a revised structuring of the breeding populations is suggested. The updating involves creation of 4 specified-trait nucleus populations originating from the current main-stream breeding population. In the main-stream population, multiple-trait selection is performed for health, growth and quality. Each of the four new nucleus populations are selected for different traits, i.e. for growth rate, wood density, health and X-mas trees respectively. In the mainstream population, the current intensity of breeding is relaxed, whereas the intensity of breeding is intensified in the much smaller nucleus populations. Most priority is at the moment put into the nucleus breeding for health to counter the current spruce decline on wind exposed sites in Denmark.
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