Staining Maize Epidermal Leaf Peels with Toluidine Blue O

Abstract

Maize is an important model organism for understanding cell patterning and development. The regular patterning of maize leaf epidermal cells has previously been characterized using the dye toluidine blue O (TBO). The polychromatic dye TBO differentially stains plant cells depending on the chemical composition of cell components and has been used to identify differences in development, cell shape and wall composition in maize. This protocol provides step-by-step instructions to fix maize leaf tissue, to peel the maize epidermis, to stain epidermal peels with TBO and finally to image using a standard light microscope. The benefit of using epidermal peels is to generate high-quality micrographs of epidermal cells for quantitative analysis. TBO staining highlights cell walls, nuclei, and differential staining of different cell types that are simple to compare, and measure.