High genetic gains in growth and resistance to white pine weevil for the next Norway spruce breeding and propagation populations in Quebec, Canada

Genetic parameters for growth (height, diameter, and volume) and resistance to the white pine weevil were estimated from 209 Norway spruce families aged 15 or 20 years old. Individual heritability values ranged from low to moderate, while family heritability values were moderate to high. This suggests that there is a genetic control for these variables. A selection index was developed to rank individuals on both volume growth and resistance to the white pine weevil. Opsel 2.0 software was used for selection to optimize genetic gain while keeping the level of relatedness between selected trees below an acceptable threshold. The selection of the best 70 individuals, i.e., the top 1% of the populations evaluated, resulted in volume gains of 15.5% and weevil resistance gains of 30.3% making it possible to create a new, more productive and weevil-resistant Norway spruce population. These new breeding and propagation populations will be planted in various locations in the province of Quebec and will be used for the operational deployment of this improved material.