Quantitative Trait Loci analysis of traits related to biomass production in willow (Salix spp.).

In this research we mapped QTLs for growth, resource-economy-related traits such as biomass allocation, water use efficiency, leaf area efficiency, leaf nitrogen content and leaf nitrogen efficiency, and phenology traits such as timing of bud burst, growth cessation, and leaf senescence, in an experimental cross of Salix viminalis L. and Salix schwerinii E. Wolf . In the QTL analysis we used a dense genetic linkage map previously constructed for the same population. The map was built using SNP markers located within genes evenly distributed throughout the Populus trichocarpa genome and it is thus aligned to the poplar physical map. Annotated genes in the regions of the poplar genome corresponding to the QTLs found in Salix were explored to identify candidate genes putatively involved in the control of these traits.