Alternative Stomata Preparation: Reprinted from: Brewer,
C. A. 1992. Responses by stomata on leaves to microenvironmental conditions. Pages
67-75, in Tested studies for laboratory teaching. Volume 13. (C. A. Goldman, Editor). Proceedings
of the 13th Workshop/Conference of the Association for Biology Laboratory
Education (ABLE), 191 pages.
- Select a plant that has been kept in the light and label the container of
the plant "LIGHT." Clip two leaves from this plant. Prepare casts of the
leaves surfaces by painting the top surface (adaxial) of one leaf and the
bottom surface (abaxial) of the other leaf with clear fingernail polish. It is
important that nail polish only be applied to dry leaves or the replica will
be cloudy and may not dry properly.
Allow the finger nail polish to dry for about 10 minutes. Note: Casts
will be very difficult to remove if you allow the nail polish to remain on the
leaf surface for more than 15 minutes.
- While the nail polish is drying, label microscope slides as either adaxial
(top of the leaf) or abaxial (bottom of the leaf).
- Cut a piece of Scotch tape
approximately 1.5 cm in length. Fold the tape over on itself leaving 0.5
cm of sticky surface exposed. Place the sticky tab of the tape at the edge
of the leaf so that it sticks to the nail polish cast (Figure
3.3). Use the remaining tape as a handle to carefully pull the nail
polish cast from the leaf surface. You will use the portion of the cast not
covered by tape to view stomata.
[View Larger Version of this Image (18K GIF file)]
3.3. Procedure for lifting a surface cast from a leaf surface.
- Place the cast on the
appropriately labelled slide. Place a coverslip over the cast. (If you would like the slide
to be permanent, place a small drop of nail polish on each corner of a coverslip. Then cover the cast with the coverslip so that the nail polish glues the coverslip to the slide.) Repeat this step for the
- Examine the slides under high
power to determine which leaf surface has stomata. Carefully survey the
entire leaf cast. The leaf surface with stomata should look similar to one
of the illustrations in Figure
3.4. For future observations, it will only be necessary to make nail
polish casts from the leaf surface with stomata.