Fig. 4
a Overview of the cell corner (3 × 3 µm2) imaged in QI™ mode. b–d 1 × 1 µm2 height-, corresponding, e–g Young’s Modulus images and h–j histograms. k Bar chart summarizing the Young’s Modulus values of the distinct cell wall layers. The transition was scanned from b the S2 to d the compound middle lamella. All images are set to the same scale, the radial direction points from right to left. The histograms show the distribution of Young’s Modulus over the 1 × 1 µm2 image. CC cell corner, CML compound middle lamella, S 1 , S 2 different layers of the secondary cell wall