Candidate gene collocation to QTL for leaf development. Example extended application of identified leaf candidate genes. A – Collocation of genes that were highly helpful for the discrimination of leaf tissue from other tissue types to QTL for leaf length in the control condition from the results of . Linkage groups are shown as grey bars and chromosomes as blue bars. SSR markers are indicated by black text and AFLP markers by grey text. Dashed grey lines connect the location of SSR markers in the linkage group and chromosome. QTL are plotted to the left of the linkage group with a horizontal line showing the peak F score location and confidence intervals plotted as verticals lines. The location of genes is indicated by horizontal lines on the chromosome with transcription factors represented by red lines and other genes by green lines. B – Expression of the two transcription factors located between flanking markers from A in four Populus microarray experiments (Seasonal data of , UPSC-TC experiment, UPSC-LP experiment, Pt-TC experiment) and of the best BLAST hit ortholog in the Arabidopsis AtGenExpress developmental baseline experiment . The transcription factor from LG III (grail3.0018017701, AT2G45190) is plotted in black and that from LG V (gw1.V.4670.1, AT5G65410) in red. C – Chromosomal location of genes (green vertical lines) and transcription factors (red vertical lines) that were informative in the discrimination of leaves from other tissues identified using Orthogonal Projection to Latent Sqaures.