Congo Red Staining: A Technique to Visualize Cellulose Deposits in Plant Stem Sections

For Congo Red staining, transfer the stem sections to a microcentrifuge tube, and add 1 milliliter of the 0.5% Congo Red solution. Gently pipette the 0.5% Congo Red solution up and down, without disturbing the sections, before incubating and washing the sections as described in the text protocol. Gently pipette the sections into a cut pipette tip, and onto a microscope slide, then, cover them with a coverslip. Observe the samples on the microscope slide under blue-light excitation using a 560-nanometer emission filter.