Localisation of genomic regions controlling microdensitometric parameters of wood characteristics in hybrid larches

The use of wood quality components in forest trees selection is hampered by long delays before phenotypic evaluation. Marker-assisted selection opens new possibilities since selection becomes feasible even before trait expression. In the present study, we have analysed 224 13-year-old hybrid larches derived from eight progenies from a single female parent in order to localise genomic regions controlling several wood traits. Traits were assessed on radial cores by microdensitometry, a method that provides estimates of wood density and radial growth and avoids tree destruction. Measurements were assessed individually on six consecutive rings. QTL detection was achieved by ANOVA using 68 AFLP markers distributed on average each 20 cM along larch genome. Significant QTLs for at least two out of six studied years are distributed on seven linkage groups. Applications towards marker-assisted selection are discussed.