The profile of the log-likelihood ratios between the full (there is a QTL) and reduced (there is no QTL) model that combines stem volume index growth trajectories and flower timing across linkage groups in the Populus deltoides parent map. The genomic positions corresponding to the peaks of the curve are the MLEs of the QTL localization. The threshold values for claiming the existence of QTL are given as the horizonal solid lines for the genome-wide level and broken lines for the chromosome-wide level. Blue color corresponds to the unifying model for jointly mapping growth trajectories and flower trait, whereas red color corresponds to a model for mapping growth trajectories only. The positions of markers on the linkage groups (Yin et al. 2002) are indicated at ticks.