Methods used for stereo and light microscopy
Begin by deciding which plant part you want to examine. What question(s) do you want to answer with your microscopic investigation?
Gather all the items you will need for preparing the plant samples, including what is needed to cut up the plant.
Using a single edge razor blade, trim the chosen plant part into working sizes. The stereo microscope will allow for larger and thicker sections than those cut for the compound light microscope. Once cut, samples can be set aside in a small petri dish of water to keep them from drying out.
Apply a few drops of water to a clean microscope slide. Set a few of the good cut plant samples in the water on the slide. When using a light microscope, cover the samples with a cover slip.
Starting with the lowest magnification of the microscope, examine your samples.
Increase the magnification as you study the samples. Vary the application of light to enhance what’s visible.
Apply coarse focus first, then fine focus as you change the level of magnification.
Sketch what you see, labeling as you go. This will help you to identify simple and complex tissues. Record observations, too – you won’t remember everything you observe!
Apply useful stains, such as toluidine blue O (or safranin and fast green), to samples as a means of emphasizing anatomical features of different plant parts.
If taking pictures, set your sample under the lens of the microscope’s camera. Adjust for magnification and camera focus. Take photo(s) and record photo content.
See the following useful references for specific details on sectioning and staining samples:
Peterson, R. Larry, Carol A. Peterson, and Lewis H. Melville. 2008. Teaching plant anatomy through creative laboratory exercises. National Research Council of Canada, Ottawa. Recommended to order through the American Phytopathological Society for lowest cost.
Koehler, Alyssa M., Maximo T. Larkin, and H. David Shew. 2020. Under the scope: Microscopy techniques to visualize plant anatomy & measure structures. The American Biology Teacher 82(4):257-260.
Parker, Alfred J., Edward F. Haskins, and Ingrith Deyrup-Olsen. 1982. Toluidine blue: A simple, effective stain for plant tissues. The American Biology Teacher 44(8):487-489.