PCA showing differences in gene expression for the total of 17 tissues under different conditions. Differences between treatments as well as high reproducibility of the biological replicates are demonstrated. Tissues not interpreted in detail are marked in grey, all tissues selected for detailed analysis are coloured. (1.2: zygotic embryos, 2.1.1: embryogenic callus (diploid), 2.1.4: embryogenic callus (tetraploid) 2.1.7: embryogenic suspension (blocked in the globular stage) before induction, 2.1.9 embryogenic suspension (blocked in the globular stage) 3 d after induction, 2.1.10: embryogenic suspension before induction, 2.1.11: embryogenic suspension 4 h after induction, 2.1.12: embryogenic suspension 3 d after induction, 2.1.14: selected torpedo-shaped embryos 3 weeks after induction, 2.3.1: non-embryogenic callus before induction)