Figure 5From: Nitrogen-driven stem elongation in poplar is linked with wood modification and gene clusters for stress, photosynthesis and cell wall formationCross sections of the elongation zone of P . trichocarpa in response to low nitrogen (A, C) and high nitrogen (B, D) supply. Lignin staining (A, B) of cross sections (50 μm thickness); autofluorescence of phenolics (C, D) in cross sections (10 μm thickness). The cross sections were taken in the second internode counted from the stem apex. The scale bars correspond to 50 μm.Back to article page