Transcript accumulation profiles from the PiceaGenExpress database (Raherison et al. []) of the P. glauca genes. The transcript abundance data are classified from 1 to 10, from lowest to highest microarray hybridization intensities detected within a given tissue. The profiles of highly expressed genes (top) (according to Raherison et al. ; class 8 to 10) are contrasted with most of the genes associated with secondary cell wall formation and nitrogen metabolism (bottom, names in bold). NA: Not detected. Tissues: B (Vegetative buds), F (Foliage), X-M (Xylem – from mature trees), X-J (Xylem –juvenile trees), P (Phelloderm), R (Adventitious roots), M (Megagametophytes), E (Embryogenic cells).