Genetically-based resistance of balsam fir (Pinaceae) to damage from the balsam twig aphid (Hemiptera: Aphididae)

Abstract

AbstractWe evaluated the effect of tree genotype on the resistance of balsam fir,Abies balsamea(Linnaeus) Miller (Pinaceae), to damage from the balsam twig aphid,Mindarus abietinusKoch (Hemiptera: Aphididae), by visually assessing aphid damage in clonal seed orchards located in New Brunswick and Nova Scotia, Canada, during four consecutive years. Estimates of clone mean heritability were moderate, suggesting that heritability of resistance is influenced by genetic factors. In New Brunswick, positive phenotypic and genetic correlations of clone-mean damage among years indicate that clones rank similarly each year. Our results suggest that selectively breeding for increased resistance could result in genetic gains.