Figure 5.

Polarization microscopy of 10-d-old hypocotyl toluidin blue-stained sections of wild-type Col-0, mur10-1, and mur10-2. Birefringence of aligned cellulose is indicated by bright contrast against gray background. The wild-type secondary wall is brightest due to its thickness. Primary walls are less bright and are contrasted equally in wild type and mutants. Dark blue deposits potentially indicate ligin.